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  • 1
    ISSN: 0263-6484
    Keywords: hepatocyte ; protein kinase ; insulin ; glucagon ; MAPK ; EGF ; epidermal growth factor ; rat ; human ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Many hepatocellular activities may be proximally regulated by intracellular signalling proteins including mitogen-activated protein kinases (MAPK). In this study, signalling events from epidermal growth factor (EGF) and insulin were examined in primary cultured human and rat hepatocytes. Using Western immunoblots, rat and human hepatocytes were found to produce a rapid tyrosine phosphorylation of the EGF receptor and MAPK following 0·5-1 min exposure to EGF. Phosphorylation of p42 and p44 MAPK was observed following 2·5 min exposure to EGF. Insulin treatment produced phosphorylation of the insulin receptor β subunit; shc phosphorylation was not observed. MAPK phosphorylation corresponded with a shift in molecular weight and an increase in kinase activity. Insulin-dependent activation of MAPK was unequivocally observed only in human hepatocytes, though a slight activation was detected in rat. Co-treatment with insulin and EGF produced phosphorylation and complete electrophoretic shift in molecular weight of MAPK, with an additive or synergistic increase in enzyme activity in rat but not human hepatocytes; human hepatocyte MAPK was maximally stimulated by EGF alone. Glucagon pretreatment blocked phosphorylation, gel mobility shift and kinase activity of MAPK induced by insulin but only partially blocked EGF-induced MAPK activation in human hepatocytes. Glucagon also reduced the activation of MAPK by EGF in rat hepatocytes. Pre-treatments with forskolin or cyclic AMP analogues diminished in the insulin-, EGF- and insulin plus EGF-dependent activation of MAPK in rat hepatocytes without effecting phosphorylation of receptors or MAPK. These results indicate that although EGF and insulin may both signal through the MAPK/ras/raf/MAPK pathway, the response for MAPK differs between these ligands and between species. Further, in both rat and human, glucagon exerts its effects through a cyclic AMP-dependent mechanism at a level in the insulin and EGF signal transduction pathways downstream of MAPK but promixal to MAPK. The partial inhibition of EGF-induced MAPK phosphorylation by glucagon in human hepatocytes provides further evidence for a raf-1-independent pathway for activation of MAPK. © 1998 John Wiley & Sons, Ltd.
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  • 2
    ISSN: 0899-0042
    Keywords: enantiospecific assay ; rat ; dog ; human ; enantiomer disposition ; HIV protease inhibitor ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: PNU-103017, 4-Cyano-N-(3-(cyclopropyl(5,6,7,8,9,10-hexahydro-4-hydroxy-2-oxo-2H-cycloocta(b) pyran-3-yl)methyl)phenyl)-benzenesulfonamide, is a selective HIV aspartyl protease inhibitor under evaluation as a potential oral treatment of Acquired Immunodeficiency Diseases. PNU-103017 is a racemic mixture of two enantiomers, designated PNU-103264 (R-) and PNU-103265 (S-). Stereoselective pharmacokinetics of the two enantiomers of PNU-103017 were observed in the dog, rat, and human after single and multiple dose administration of the racemate and were apparently species-dependent. Mean enantiomeric ratios of plasma concentrations (R-/S-) at each time point were greater than 1 in the dog, ranging from 1.22 to 3.06, but less than 1 in the rat and in the human, ranging from 0.44 to 0.80 and 0.23 to 0.73, respectively. A trend towards increased or decreased (farther from 1:1, R-/S-) enantiomeric ratio of plasma concentrations with time after each administration was also observed. The enantiomeric ratio remained unchanged after multiple dose administration in the rat, dog, and human although enzyme induction and increased plasma clearance were observed for both enantiomers. Chirality 10:210-216, 1998. © 1998 Wiley-Liss, Inc.
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  • 3
    ISSN: 0730-2312
    Keywords: cartilage ; aging ; osteoarthritis ; programmed cell death ; cell culture ; human ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: The regulation of chondrocyte apoptosis in articular cartilage may underlay age-associated changes in cartilage and the development of osteoarthritis. Here we demonstrate the importance of Bcl-2 in regulating articular chondrocyte apoptosis in response to both serum withdrawal and retinoic acid treatment. Both stimuli induced apoptosis of primary human articular chondrocytes and a rat chondrocyte cell line as evidenced by the formation of DNA ladders. Apoptosis was accompanied by decreased expression of aggrecan, a chondrocyte specific matrix protein. The expression of Bcl-2 was downregulated by both agents based on Northern and Western analysis, while the level of Bax expression remained unchanged compared to control cells. The importance of Bcl-2 in regulating chondrocyte apoptosis was confirmed by creating cell lines overexpressing sense and antisense Bcl-2 mRNA. Multiple cell lines expressing antisense Bcl-2 displayed increased apoptosis even in the presence of 10% serum as compared to wild-type cells. In contrast, chondrocytes overexpressing Bcl-2 were resistant to apoptosis induced by both serum withdrawal and retinoic acid treatment. Finally, the expression of Bcl-2 did not block the decreased aggrecan expression in IRC cells treated with retinoic acid. We conclude that Bcl-2 plays an important role in the maintenance of articular chondrocyte survival and that retinoic acid inhibits aggrecan expression independent of the apoptotic process. J. Cell. Biochem. 71:302-309, 1998. © 1998 Wiley-Liss, Inc.
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  • 4
    ISSN: 0730-2312
    Keywords: bone marrow stroma ; human ; differentiation ; TGF-β ; BMP-2 ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Osteoprogenitor cells in the human bone marrow stroma can be induced to differentiate into osteoblasts under stimulation with hormonal and local factors. We previously showed that human bone marrow stromal (HBMS) cells respond to dexamethasone and vitamin D by expressing several osteoblastic markers. In this study, we investigated the effects and interactions of local factors (BMP-2 and TGF-β2) on HBMS cell proliferation and differentiation in short-term and long-term cultures. We found that rhTGF-β2 increased DNA content and stimulated type I collagen synthesis, but inhibited ALP activity and mRNA levels, osteocalcin production, and mineralization of the matrix formed by HBMS cells. In contrast, rhBMP-2 increased ALP activity and mRNA levels, osteocalcin levels and calcium deposition in the extracellular matrix without affecting type I collagen synthesis and mRNA levels, showing that rhBMP-2 and rhTGF-β2 regulate differentially HBMS cells. Co-treatment with rhBMP-2 and rhTGF-β2 led to intermediate effects on HBMS cell proliferation and differentiation markers. rhTGF-β2 attenuated the stimulatory effect of rhBMP-2 on osteocalcin levels, and ALP activity and mRNA levels, whereas rhBMP-2 reduced the rhTGF-β2-enhanced DNA synthesis and type I collagen synthesis. We also investigated the effects of sequential treatments with rhBMP-2 and rhTGF-β2 on HBMS cell differentiation in long-term culture. A transient (9 days) treatment with rhBMP-2 abolished the rhTGF-β2 response of HBMS cells on ALP activity. In contrast, a transient (10 days) treatment with rhTGF-β2 did not influence the subsequent rhBMP-2 action on HBMS cell differentiation. The data show that TGF-β2 acts by increasing HBMS cell proliferation and type I collagen synthesis whereas BMP-2 acts by promoting HBMS cell differentiation. These observations suggest that TGF-β2 and BMP-2 may act in a sequential manner at different stages to promote human bone marrow stromal cell differentiation towards the osteoblast phenotype. J. Cell. Biochem. 68:411-426, 1998. © 1998 Wiley-Liss, Inc.
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  • 5
    ISSN: 0952-3499
    Keywords: substance P ; endopeptidase ; spinal cord ; cerebrospinal fluid ; human ; purification ; characterization ; ÄKTATM ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: An enzyme activity capable of hydrolysing the neuroactive undecapeptide substance P (SP) between its Phe7-Phe8 residues was purified from the membrane-bound fraction of human spinal cords. The enzyme preparation yielded was compared with a previously described SP-hydrolysing enzyme from human cerebrospinal fluid (CSF) with regard to inhibition profile, protein chemical properties and kinetics. In addition, the results were compared with those of bovine pancreatic chymotrypsin (a serine protease that cleaves the carboxy-terminal side preferentially at hydrophobic amino acids). The SP peptidase activity was extracted from human spinal cords with 1% Triton X-100 in 20 mM Tris-HCl pH 7.8. After ion exchange chromatography (DEAE-Sepharose) where the enzyme activity was separated from other proteins by gradient elution, the pooled enzyme fraction was further purified by molecular sieving (Sephadex G-50). The enzyme activity was finally recovered by HPLC molecular sieving (Superdex® 75 HR 10/30) using a new preparative system, ÄKTATM-purifier, controlled by UNICORN® software version 2.20. Copyright © 1998 John Wiley & Sons, Ltd.
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  • 6
    ISSN: 0021-9304
    Keywords: osteogenesis ; proliferation ; differentiation ; osteoblast ; human ; hydroxyapatite ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine , Technology
    Notes: In order to evaluate whether human osteoblastic cells differentiate normally on hydroxyapatite, we have compared the adhesion, proliferation, and differentiation of human trabecular (HT) osteoblastic cells on synthetic-dense hydroxyapatite and on standard plastic culture. We show here that initial HT cell attachment was 4-fold lower on hydroxyapatite than on plastic after 4 h of culture, and that normal cell attachment on hydroxyapatite was restored after 18 h of culture. HT cell proliferation was similar on the two substrates at 2-8 days of culture, but was lower on hydroxyapatite compared to plastic after 15 and 28 days of culture, as evaluated by DNA synthesis or cell number. HT cells cultured on both substrates produced an abundant extracellular matrix which immunostained for Type I collagen. The levels of carboxyterminal propeptide of Type I procollagen (P1CP) in the medium were lower in HT cell cultures on hydroxyapatite than on plastic. In addition, (3H)-proline incorporation into matrix proteins and the mean thickness of matrix layers were 52% and 26% lower, respectively, on hydroxyapatite compared to plastic after 4 weeks of culture, indicating that the total collagenous matrix synthesized by HT cells was lower on hydroxyapatite. However, (3H)-proline and calcium uptake expressed per cell was higher on hydroxyapatite than on plastic. The results show that human osteoblastic cells attach, proliferate, and differentiate on dense hydroxyapatite with a sequence similar to that of plastic. However, the growth of human osteoblastic cells is lower on hydroxyapatite in long-term culture, which results in a reduced amount of extracellular matrix, although matrix production per cell may be increased. © 1997 John Wiley & Sons, Inc. J Biomed Mater Res, 37, 508-516, 1997.
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  • 7
    ISSN: 0952-3499
    Keywords: monoclonal antibodies ; human ; antigen ; mouse ; allergen ; phospholipane ; epitope mapping ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Two human and twelve murine monoclonal antibodies directed against the main bee venom allergen phospholipase A2 (PLA) were evaluated for their fine specificity of binding to antigen and their ability to inhibit the enzymatic activity of the antigen. Antibodies were induced by natural exposure of beekeepers to bee venom or immunization of mice via different methods. Both human monoclonal antibodies (hmAbs) were previously shown to recognize the native three-dimensional conformation of PLA and are directed against discontinuous epitopes which include lysine residue at position 25 as a contact residue. In contrast, six of the murine monoclonal antibodies (mmAbs) bind to the denatured structure of the protein as determined by enzyme-linked immunosorbent assay. The epitopes recognized are located near the C-terminal end (n=8), in the centre of the polypeptide (n=1), near the N-terminal end (n=1) or include the carbohydrate part (n=2) of the PLA molecule. The capacity of the antibodies to modify the enzymatic activity was also determined. The hmAbs significantly inhibit the enzyme (70-79%), whereas the mmAbs produced various degrees of inhibition (39-100%). Since the X-ray structure of PLA is known, the epitopes can be visualized in the context of the three-dimensional structure of the antigen. A qualitative correlation was found between the location of epitopes and the inhibition pattern. Strong inhibition was seen with those antibodies that recognize epitopes that lie on the surface of the enzyme that is thought to contact the phospholipid bilayer. The results show that even though both hmAbs and most mmAbs inhibit the enzymatic activity of PLA, the antigen-binding properties of antibodies from different species raised after different routes of immunization differ significantly. Thus, detailed epitope mapping studies using murine antibodies prepared by artificial immunization may have limited value in predicting epitope patterns relevant to an antibody response to allergens in humans naturally exposed to antigen/allergen. © 1997 John Wiley & Sons, Ltd.
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  • 8
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Bioelectromagnetics 18 (1997), S. 166-171 
    ISSN: 0197-8462
    Keywords: extremely low frequency ; electromagnetic field ; human ; neuroendocrine ; cancer ; Life and Medical Sciences ; Occupational Health and Environmental Toxicology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Physics
    Notes: This report describes the third in a series of double-blind, laboratory-based studies that were aimed at determining the effects of nocturnal exposure to power frequency magnetic fields on blood levels of melatonin in human volunteers. Our two earlier studies evaluated effects on melatonin of intermittent exposure to 60 Hz circularly polarized magnetic fields at 10 and 200 mG. No overall effects on melatonin levels were found. In the present study, men were exposed continuously rather than intermittently through the night to the same 200 mG magnetic field condition that was used previously; again, no overall effects on melatonin levels were found. We conclude that the intermittent and continuous exposure conditions used in our laboratory to date are not effective in altering nocturnal blood levels of melatonin in human volunteers. Bioelectromagnetics 18:166-171, 1997. © 1997 Wiley-Liss, Inc.
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  • 9
    ISSN: 0730-2312
    Keywords: human ; C-reactive protein ; acute phase reactant ; monocytes ; leukocyte ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: C-reactive protein (CRP), the prototypical inflammatory acute phase reactant in humans, interacts with monocytes and neutrophils via a specific receptor. To map the site on CRP recognized by the CRP receptor (CRP-R), synthetic peptides corresponding to the surface region on each of the five identical subunits were tested as competitors vs. [125l]-CRP for cell binding. A peptide of residues 27-38 (TKPLKAFTVCLH) efficiently inhibited CRP binding when compared to other nonoverlapping peptides. This peptide was termed the cell-binding peptide (CB-Pep). The F(ab′)2 of an IgG Ab to the CB-Pep specifically inhibited CRP binding upon reacting with the ligand. Competitive binding studies with synthetic peptides truncated from either the NH2- or COOH-terminus of the CB-Pep revealed that the minimum length recognized by the CRP-R consisted of residues 31-36: KAFTVC. Conservative substitutions of residues within the CB-Pep indicated that the four residues AFTV were critical for CRP-R binding. The CB-Pep also inhibited induced superoxide generation by HL-60 granulocytes. The minimum length required for the inhibition was also KAFTVC; however, only Phe-33 and Leu-37 were critical residues in this assay. Anti-CB-Pep IgG Ab reacted more extensively with heat-modified CRP, suggesting that an altered conformation of CRP is preferentially recognized by the CRP-R. The results suggest that this contiguous sequence on a β-strand on one face of each of five subunits of the CRP pentamer serves as a unique recognition motif for inflammatory leukocytes. J. Cell. Biochem. 64:140-151. © 1997 Wiley-Liss, Inc.
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  • 10
    ISSN: 0730-2312
    Keywords: DNA strand breaks ; superoxide ; granulocytes ; human ; okadaic acid ; fluoride ; staurosporine ; phorbol myristate acetate ; hydrogen peroxide ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Phorbol ester treatment of granulocytes triggers release of superoxide (O2-) and a concomitant burst of DNA strand breaks. The relationship between the amount of O2- and the number of DNA breaks has not previously been explored. To quantify the relatively large amount of O2- generated over a 40-min period by 1 × 106 granulocytes/mL, a discontinuous “10-min pulse” method employing cytochrome c was used; 140 nmol O2- per 1 × 106 cells was detected. DNA strand breaks were quantified by fluorimetric analysis of DNA unwinding (FADU). To vary the level of O2- released by cells, inhibitors of the respiratory burst were used. Sodium fluoride (1-10 mM) and staurosporine (2-10 nM) both inhibited O2- production. In both cases, however, inhibition of strand breakage was considerably more pronounced than inhibition of O2-. Zinc chloride (50-200 μM) inhibited both O2- and DNA breaks, approximately equally. Dinophysistoxin-1 (okadaic acid) inhibited O2- production more effectively than it inhibited DNA breaks. O2- dismutes to H2O2, a reactive oxygen species known to cause DNA breaks. The addition of catalase to remove extracellular H2O2 had no effect on DNA breakage. Using pulse field gel electrophoresis, few double-stranded breaks were detected compared to the number detected by FADU, indicating that about 95% of breaks were single-stranded. The level of DNA breaks is not directly related to the amount of extracellular O2- or H2O2 in PMA-stimulated granulocytes. We conclude that either an intracellular pool of these reactive oxygen species is involved in breakage or that the metabolic inhibitors are affecting a novel strand break pathway. J. Cell. Biochem. 66:219-228, 1997. © 1997 Wiley-Liss Inc.
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  • 11
    ISSN: 0899-0042
    Keywords: proton pump inhibitor ; pantoprazole ; stereoselective pharmacokinetics ; genetic polymorphism ; human ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Pantoprazole (PAN) is a proton pump inhibitor that is administered as a racemic mixture. The pharmacokinetics of PAN enantiomers were investigated in extensive metabolizers (EMs) and apparent poor metabolizers (PMs) of PAN who received a single 40, 60, or 80 mg oral dose of racemic PAN as enteric-coated formulation. In the EMs, the serum concentrations of (-)-PAN were slightly higher than those of (+)-PAN at each dose level. The (+)/(-) ratios for the area under the concentration-time curve (AUC) and the half-life were 0.58-0.89 and 0.62-0.88, respectively. In the PMs, the serum concentrations of both enantiomers were much higher than those in the EMs at each dose level and significant differences in pharmacokinetics of (+)- and (-)-PAN were observed. The half-lives for (+)-PAN were 2.67-3.77 times longer than those for (-)-PAN. The AUCs for (+)-PAN were 2.65-3.45 times greater than those for (-)-PAN. Therefore, the metabolism of (+)-PAN is impaired to a greater extent than (-)-PAN in the PMs, which resulted in the stereoselective disposition of PAN in the PMs. It has been suggested that the EMs and the PMs of PAN could be differentiated by determining the (+)/(-) enantiomer ratio in serum at one time point, possibly 2-6 h after oral dosing, because the (+)/(-) enantiomer ratios in the PMs were opposite those in the EM subjects. Chirality 9:17-21, 1997 © 1997 Wiley-Liss, Inc.
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  • 12
    ISSN: 0197-8462
    Keywords: ELF ; EMF ; human ; neuroendocrine ; cancer ; Life and Medical Sciences ; Occupational Health and Environmental Toxicology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Physics
    Notes: Two double-blind laboratory-based studies were performed to determine whether a suppression of nocturnal melatonin similar to that observed in rodents occurs when humans are exposed to magnetic fields at night. In study 1, 33 men were exposed to sham, 10 mG, or 200 mG intermittent, circularly polarized magnetic fields from 2300 to 0700 h under controlled environmental and exposure test conditions. Overall, exposure had no effect on melatonin levels. Men with preexisting low levels of melatonin, however, showed significantly greater suppression of melatonin when they were exposed to light and also when they were exposed to the 200 mG magnetic-field condition. Study 2 directly tested the hypothesis that low-melatonin subjects show enhanced sensitivity when exposed to light and to 200 mG magnetic fields. After preexposure screening, each of 40 men slept in the exposure facility on two nights. On one night, the men were sham exposed. On the other night, they were exposed to the 200 mG field condition used previously. Again, exposure had no overall effect on melatonin levels. The original finding of enhanced sensitivity in low-melatonin subjects was not replicated in this study. We conclude that the intermittent exposure conditions used in these two studies were not effective in altering nocturnal melatonin release patterns in human volunteers. Further research is underway with regard to exposure parameters, hormonal and immune system measures, and individual differences. © 1996 Wiley-Liss, Inc.
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  • 13
    Electronic Resource
    Electronic Resource
    New York, N.Y. : Wiley-Blackwell
    Journal of Cellular Biochemistry 63 (1996), S. 1-11 
    ISSN: 0730-2312
    Keywords: cell culture ; lung carcinoma ; human ; retroviruses ; HIV ; Life Sciences ; Molecular Cell Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: The NCI series of cell lines represent a unique collection of permanent human tumor cell lines established by one laboratory over a period of approximately 16 years. More than 300 cell lines were established, mainly from human lung cancers (both small cell and non-small cell types). In addition, smaller numbers of lines were established from rare and unusual tumors such as cutaneous T cell lymphomas, myelomas and adrenal cortical carcinoma. The T cell lines played a pivotal role in the isolation of human retroviruses including HTLV-1 and HIV. The establishment of such a large panel of lines was aided by the development of defined media for culturing specific cell types. The lines are well characterized, and full clinical data are available for most of them. Many of the lines have been deposited with the American Type Culture Collection, Rockville, MD, where they are readily available for a modest handling fee. The lines have been widely distributed to investigators, and have had a major impact on biomedical research. © 1996 Wiley-Liss, Inc.
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  • 14
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Clinical Anatomy 8 (1995), S. 219-221 
    ISSN: 0897-3806
    Keywords: splenic artery ; tortuosity ; primates ; pig ; greyhound ; human ; Life and Medical Sciences ; Miscellaneous Medical
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The splenic artery of four mammals-pig, greyhound, rhesus macaque, and olive baboon-was studied to determine its tortuosity and pattern of convolutions. The results were compared to those previously gathered in humans. It was found that the isolated cadaveric arteries showed a noticeable species variation in mean index of tortuosity. In the pig and dog, the artery was nearly straight throughout its length, with a very low index of tortuosity, not significantly different in the two species (P 〉0.1). The artery was significantly more tortuous in the rhesus macaque and baboon than in both pig and dog, (Ps 〈 0.001), with a single large convolution present in the proximal one-third. In humans, the artery is commonly tortuous throughout its length and is significantly more tortuous than in the pig and dog (P 〈 0.001), but not significantly more tortuous than in the baboon (P 〉 0.1) and only just significantly more so than in the rhesus macaque (0.02 〈 P 〉 0.05). The speculation that the tortuosity of the artery may be related to habitual posture, being less in the pronograde pig and dog than in the partly orthograde rhesus macaque and baboon, is not supported by results in the wholly orthograde human. © 1995 WiIey-Liss, Inc.
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  • 15
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Clinical Anatomy 8 (1995), S. 379-387 
    ISSN: 0897-3806
    Keywords: gross anatomy ; human ; inferior laryngeal artery ; inferior laryngeal nerve ; internal laryngeal nerve ; Life and Medical Sciences ; Miscellaneous Medical
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The morphological patterns of the inferior laryngeal nerve and internal laryngeal nerve display complex arborizations. This paper attempts to identify and clarify these patterns.Dissections were performed on 105 adult Japanese cadavers, and observations were made on 201 sides. Results showed that the communications between the inferior laryngeal nerve (ILN) and internal laryngeal nerve (ITLN) could be classified into two types and three subtypes. Also, the ITLN displayed three characteristic patterns at the arytenoid cartilage. These communications produce complex arborizations of the ILN as it enters the larynx. This may explain the variety of potential clinical symptoms observed after thyroid surgery or neck dissections. © 1995 WiIey-Liss, Inc.
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  • 16
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 11 (1995), S. 337-342 
    ISSN: 0749-503X
    Keywords: Saccharomyces cerevisiae ; Caenorhabditis elegans ; plant ; human ; Plasmodium falciparum ; pre-mRNA splicing ; RNA binding protein ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
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  • 17
    ISSN: 0730-2312
    Keywords: human ; myeloid ; nuclear ; differentiation ; chronic myeloid leukemia ; Burkitt's lymphoma ; Epstein-Barr virus ; interferon-α ; PHA ; phorbol ester ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: The expression of the human myeloid cell nuclear differentiation antigen (MNDA) was observed specifically in cells of the granulocyte-macrophage lineage in our earlier reports. The specificity of MNDA expression for cells in the granulocyte-macrophage lineage was reexamined in cell line established from patients with philadelphia chromosome-positive chroni myeloid leukemia. Cell lines that expressed MNDA exhibited myeloid cell features and granulocyte or monocyte defferentiation could be induced in vitro, while cell lines exhibiting properties of very early stage cells of multipotential cells ded not express MNDA. Cells orginating from cases of burkitt's lymphoma were negative. By contrast, three Iymphoblastoid cell lines (immortalized in vitro with Epstein-Barr virus) were weakly positive and MNDA was up-regulated by interferon-α (IFN-α) treatment. As we reported previously, MNDA mRNA level in adherent monocytes is elevated by IFN-α; in this study, we further assessed MNDA expression in in vitro monocyte-derived macrophages. Three addditional agents (endotoxin, phytohemagglutinin, and photbol ester) and other conditions that affect function, cutokine production, defferentiation, and/of growth of monocytes were examined for their ability to alter MNDA expression. The results varied with the agent, cell type, and stage of differentiation. Changes in MNDA expression occurred slowly (hours to days), suggesting that MNDA could mediate changes realized over a long period. The results also reveal a discordance in certain MNDA Positiva cells between steady-state levels of changes in levels of protein and mRNA indicating that the regulation of MNDA expression occurs at more than one point. Changes in MNDA expression are consistent with a role in opposing macrophage defferentiation and activation of monocytes/macrophages.
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  • 18
    ISSN: 0897-3806
    Keywords: gross anatomy ; human ; subclavian lymphatics ; axillary lymphatics ; Life and Medical Sciences ; Miscellaneous Medical
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Detailed dissections were performed bilaterally on 90 human adult cadavers to obtain more accurate data on the course and origin of the subclavian lymphatics and especially of the subclavian lymphatic trunk. We classified these into four types from the morphology. Type A (46.1 %): The subclavian lymphatics were located along the medial edge of the subclavian vein edge close to the lateral thoracic wall. In this type, the subclavian lymphatics consisted of the subclavian node chain, interconnecting vessels, and short lymph trunks. Type B (20.0%): A large connecting vessel ran along the lateral edge of the subclavian vein or on the subclavian artery, with the result that the trunk was located away from the thoracic wall. In the Type B configuration, the vessels originated from the nodes near the origin of the thoracoacromial artery. Type C (21.7%): The Type B large collecting vessel was observed with the Type A subclavian lymphatics. Type D (12.2%): Lymph vessels were too fine to be found and dissected in the subclavian lymphatics. These observations provide critical information for an unproved clinical examination and lymphatic resection of breast cancer. © 1994 Wiley-Liss, Inc.
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  • 19
    Electronic Resource
    Electronic Resource
    New York, N.Y. : Wiley-Blackwell
    Journal of Cellular Biochemistry 53 (1993), S. 181-189 
    ISSN: 0730-2312
    Keywords: G proteins ; liver ; insulin ; rat ; human ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Plasma membranes (1-2 mg protein) prepared from the livers of adult male rats and human organ donors were incubated with 0.6 μM [α-32P] guanosine triphosphate (GTP) in an adenosine triphosphate (ATP)-regenerating buffer at 37°C for 1 h; during this incubation, the [32P]GTP is hydrolyzed and the nucleotide that is predominantly bound to the membranes is [32P] guanosine diphosphate (GDP). [32P]GDP release from the liver membranes was proportional to the protein concentration and increased as a function of time. At 5 mM, Ca2+, Mg2+, Mn2+, and Zn2+ maximally inhibited GDP release by 80-90%, whereas, 5 mM Cu2+ maximally stimulated the reaction by 100%. Therefore, cations were not included in the buffer used in the GDP release step. One μM Gpp(NH)p (5′-guanylylimidodiphosphate), a nonhydrolyzable analog of GTP, maximally stimulated [32P]GDP release in the liver membranes by up to 30%. Although 10 nM Gpp(NH)p had no effect on GDP release, it appeared to stabilize the hormonal effect by blocking further GDP/GTP exchange.In the rat membranes, 1-100 nM glucagon (used as a positive control) stimulated [32P]GDP release by about 17% (P 〈 .05); similarly, 0.1-100 nM insulin stimulated [32P]GDP release by 10-13% (P 〈 .05). In the human membranes, 10 pM to 100 nM insulin stimulated [32P]GDP release by 7-10%. In the rat membranes, 10 nM insulin stimulated [32P]GDP release by 17 and 24% at 2 and 4 min, respectively (P 〈 .05); in the human membranes, 10 nM insulin stimulated [32P]GDP release by about 9% at 2 and 4 min. Normal rabbit IgG (used as a control for insulin receptor antibody) by itself stimulated the GDP release by rat and human membranes. However, the stimulation of the GDP release by insulin receptor antibody was consistently higher than that observed with normal rabbit IgG. Four to 15 μg of insulin receptor antibody stimulated [32P]GDP release by 12-22% (P 〈 .05) and 7-14% in rat and human membranes, respectively. These results indicate that ligand binding to the insulin receptor results in a functional interaction of the receptor with a guanine nucleotide-binding transducer protein (G protein) and activation of GTP/GDP exchange.
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  • 20
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Clinical Anatomy 4 (1991), S. 109-116 
    ISSN: 0897-3806
    Keywords: energy-dispersive x-ray analysis ; EDAX ; human ; spinal cord ; Life and Medical Sciences ; Miscellaneous Medical
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Calcified or ossified plaques within the spinal arachnoid membranes are often reported at autopsy and are occasionally incriminated as the cause of neurological symptoms in patients undergoing surgery. Histological studies of plaques have been done, but to our knowledge no studies using the scanning electron microscope (SEM) have been reported. In this study, portions of the spinal cord with plaques were removed from adult human cadavers in the dissecting laboratory and processed for SEM and energy-dispersive x-ray analysis (EDAX). The surfaces of the plaques appeared to be fibrous in some areas, studded with irregularly shaped projections or nodules in others, and smooth in yet other areas. Cells were seen in lacunae-like depressions on the surfaces of some plaques and EDAX revealed the presence of calcium on and near the cells. In some areas calcium and phosphorus were both detected, but not in the ratios seen in bone. No calcium was seen on smooth or fibrous areas. It is suggested that the plaques sampled in this study were composed largely of fibrous tissue encrusted in some areas with calcium salts. There was no evidence that any of the plaques contained bone.
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  • 21
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Clinical Anatomy 3 (1990), S. 183-194 
    ISSN: 0897-3806
    Keywords: human ; configuration ; measurement ; Life and Medical Sciences ; Miscellaneous Medical
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Descriptions are given of the main pulmonary arteries and of their lobar branches in man. The numbers of lobar branches and certain dimensions (mainly external diameters) of parent vessels (at specified fixed points) and of branch vessels (at their origins) are also given. This information has been obtained from studies made in living subjects. Attention is drawn to the relative frequency of incidence of a large proximally sited branch to the upper lobe in both lungs, also to the site of origin of the lower lobe apical artery, relative to the middle lobe artery or lingular artery. Certain anomalous and small arterial branch arrangements are described.
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  • 22
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Gamete Research 24 (1989), S. 67-80 
    ISSN: 0148-7280
    Keywords: mouse ; human ; abnormal hatching ; twinning ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Hatching in vitro was studied following zona drilling of 507 two-cell mouse embryos using three methods: 1) acidic Tyrode's (AT), 2) partial zona dissection (PZD) using a sharp micronecdle, and 3) zona chiseling (CH), using a large beveled needle. PZD and CH were performed while the embryos were kept in a sucrose/PBS solution. Hatching was compared to 191 umnicromanipulated controls. The incidences of cavitation and completion of hatching did not differ between groups, however more micromanipulated embryos (20-25%) hatched partially than controls (9%). The zona pellucida thinned in 59/59 (100%) control blastocysts during expansion, but in only 3/205 (2%) micromanipulated blastocysts. The hatching gap was wide in all control embryos, but smaller in 96/129 (75%) micromanipulated embryos. Partially hatched blastocysts with a ‘figure-8’ shape were found in 59/129 (46%) micromanipulated embryos and in none of the 39 hatching controls. Hatching usually occurred a day earlier in micromanipulated embryos as 214/218 (98%) had started extruding on day 5 as compared to 20/59 (27%) control blastocysts. Fifty percent of 1-day-old human oocytes were fertilized following PZD and reinsemination and 15/31 (48%) were monospermic. Thirteen monospermic embryos cleaved, six compacted and four cavitatcd - of these, three extruded through the PZD incision upon expansion. The zonae did not thin and one blastocyst twinned spontaneously as it was caught between the thick ridges of the PZD hole. Results indicate that the hatching process is abnormal following zona drilling; more embryos start hatching, extrusion occurs earlier, and many become trapped which may lead to artificial twinning or the formation of trophoblastic vesicles.
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  • 23
    ISSN: 0197-8462
    Keywords: human ; calorimetry ; dielectric heaters ; Life and Medical Sciences ; Occupational Health and Environmental Toxicology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Physics
    Notes: The heat uptake that resulted from immersing the hand and wrist into a water-filled calorimeter maintained at temperatures between 37-40 °C was measured under standard conditions in a group of eight subjects of either sex. The rate of heat transfer (W) increased exponentially with temperature and was a function of hand or body size and age, but not sex. The heat transfer rate normalized to hand mass (W.kg-1) was determined by temperature and age: best-fit mean values (and 95% confidence limits of the population) were 6.0 W.kg-1 (3.2-11.2 W.kg-1) at an immersion temperature of 37 °C and 25.4 W.kg-1 (13.7-47.0 W.kg-1) at 40 °C. The application of these results to limits on specific energy absorption rate induced in the hands and wrists by radiofrequency dielectric heat sealer welders is discussed.
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  • 24
    ISSN: 0263-6484
    Keywords: Polyclonal antiserum ; receptor ; human ; uterus ; breast ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Polyclonal antiserum was generated in guinea pigs immunized with the 116 000 Mr rabbit uterine progesterone receptor (PR). The PR antigen was partially purified by DEAE-cellulose chromatography and preparative sodium dodecyl sulphate-polyacrylamide gel electrophoresis, transferred to nitrocellulose, and the 116 000 Mr band excised and injected into guinea pigs. The antiserum recognized on protein blots rabbit uterine PR of Mr 116 000 and 81 000. The antiserum was judged to be specific for PR from normal and malignant human tissues as determined by sedimentation shift on sucrose gradients, immunoprecipitation studies, protein blotting, and fluorographic analysis using photolabelled samples. Comparison of protein blots probed with this polyclonal antiserum or with a recently obtained monoclonal antibody to human PR indicated that similar PR structures were recognized in rabbit and human samples by both antisera. Characterization of the polyclonal antiserum has demonstrated its suitability for investigating the immunolocalization or PR in normal and malignant human tissues as well as the receptor structure detected on protein blots.
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  • 25
    ISSN: 0899-0042
    Keywords: pharmacokinetics ; terbutaline ; enantiomers ; human ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Terbutaline is a β2-agonist and administered as the racemic mixture. The pharmacokinetics of the separate enantiomers differ with respect to degree of absorption and clearance. In the present study, repeated doses of racemic terbutaline were given to six healthy volunteers. Plasma was analyzed for the concentrations of the two enantiomers. The observed plasma concentrations at steady state differed from those predicted from the values observed after single dose administration of the separate enantiomers. The difference between the observed and predicted values can be tentatively explained by a combined influence of (-)-terbutaline on the absorption of (+)-terbutaline and the influence of (+)-terbutaline on the elimination of (-)-terbutaline. The results have implications for the interpretation of effect/concentration studies with terbutaline, but do not affect the doses used in clinical practice.
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  • 26
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Clinical Anatomy 2 (1989), S. 63-67 
    ISSN: 0897-3806
    Keywords: osteology ; sacrum ; ilium ; human ; Life and Medical Sciences ; Miscellaneous Medical
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: To investigate sex differences in the morphology of the auricular surfaces of the human sacroiliac joint, 153 dried bone sets of unknown ages, and of Indian origin were studied, and various measurements were made of the corresponding iliac and sacral auricular surfaces. Some significant differences. The sacral and iliac auricular surfaces was larger and longer in males. The most prominent point on the ventral border of the iliac auricular surface was situated more caudally in females. The iliac angle was larger in males. The deepest point of the dorsal border of the iliac auricular surface was more caudal in females.
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  • 27
    ISSN: 0148-7280
    Keywords: acrosome reaction ; sperm ; human ; fine structure ; follicular fluid ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: It has been suggested that the morphology of the human sperm acrosome reaction (AR) is markedly different from that of other mammalian sperm. The present study examines the fine structural events of the early stages of the human sperm AR as initiated by preovulatory human follicular fluid. Human sperm, capacitated in vitro for 6 hr at 40°C (90% motility) were diluted with equal volumes of follicular fluid before fixing in cacodylate-buffered glutaraldehyde at 5, 10, 15, 20, and 180 sec. Fixed sperm were treated with either tannic acid or thiocarbohydrazine and OsO4. Over 2,000 sperm were viewed. By 5 sec, 2% of the sperm had initiated the AR. By 15 sec, 8% of the sperm were in some stage of the reaction, and after 180 sec 40% of the sperm had completed the acrosome reaction. The initial stages of the human AR are characterized by a swelling or decondensation of the acrosomal matrix. The fusion between the plasma membrane and outer acrosomal membrane begins at the most anterior tip of the head and progresses toward the equatorial segment. Fusion and fenestration ended at the equatorial segment. With thiocarbohydrazine + OsO4 fixation the fused membranes are distinct hybrid vesicles with the outer acrosomal membrane being far more electron dense. The acrosomal matrix is retained by 20 sec, but by 180 sec the matrix is completely dispersed, even when viewed after tannic acid fixation. Also by 180 sec, vesicles were being progressively lost. It is therefore concluded that the morphology of the human sperm AR, as initiated by human follicular fluid, is not unique, but is similar to that described for other mammalian sperm.
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  • 28
    ISSN: 0148-7280
    Keywords: human ; spermatozoa ; cryopreservation ; freezing-thawing ; chromatin ; acridine orange ; Feulgen-DNA ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Cryopreservation and freezing-thawing effects on the fertilizing ability of human spermatozoa commonly are evaluated by post-thaw motility. Various studies have depicted the ultrastructural changes caused by freezing-thawing, yet the chromatin alterations have been studied very limitedly. Our aim was to determine the extent to which freezing-thawing alters the chromatin of human spermatozoa, using two analytical methods: acridine orange staining and Feulgen-DNA cytophotometric studies. Both methods revealed a dramatic effect of freezing-thawing on sperm chromatin: the native DNA content decreased as did the Feulgen-DNA content, and sperm surface area was reduced. These results indicate an effect on DNA, diminished accessibility for Feulgen, and a decrease in nuclear surface area and prompt us to hypothesize a relationship between an “overcondensation” state for sperm chromatin after freezing-thawing and a lower conception rate for human semen after cryostorage.
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  • 29
    ISSN: 0148-7280
    Keywords: human ; spermatozoa ; egg extract ; Xenopus laevis ; pronucleus ; chromosome ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The conditions necessary for inducing pronucleus formation and chromosome condensation of human sperm nuclei were studied using Xenopus egg extracts. When lysolecithin (LC)-and dithiothreitol (DTT)-treated spermatozoa were incubated with egg extract prepared with an extraction medium containing 10 mM EGTA, sperm nuclei transformed into chromosomes, bypassing the pronuclear stage. On the contrary, LC-DTT-treated spermatozoa incubated in egg extract without EGTA mimicked LC-permeabilized Xenopus spermatozoa in that they underwent pronucleus formation accompanied by DNA synthesis and subsequent chromosome condensation in the correct chronological order. These observations suggest the importance of intracellular calcium for regulating the states of nuclear chromatin. LC-permeabilized human spermatozoa were not responsive to the egg extract without any additives, but formed pronuclei when incubated with the egg extract supplemented with 5-10 mM DTT. However, subsequent chromosome condensation of sperm nucleus did not occur in the DTT extract. This suggests that disulfide-reducing agent blocks transformation of sperm pronuclei into condensed chromosomes.
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  • 30
    ISSN: 0148-7280
    Keywords: sperm ; human ; sperm motility ; kinematics ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Tracks of 30 progressively motile washed human spermatozoa were plotted manually from 200-Hz frame rate video recordings. Tracks at 100, 66.7, 50, 40, 33.3., 25, 20, 10, and 5 Hz were then constructed using every 2nd, 3rd, 4th, 5th, 6th, 8th, 10th, 20th, or 40th point. The 200-Hz tracks were analyzed by traditional manual methods, and all ten sets of tracks analyzed using a computer-assisted method (“Videomot,” developed originally to analyze 30-Hz tracks) to eliminate observer bias. Progression velocity (VSL) remained constant under all analysis conditions. Average path velocity (VAP) also remained essentially constant, although Videomot was less reliable at high frame rates due to problems in determining the average path. Curvilinear velocity (VCL) was very frame rate dependent (the 25-Hz mean value was only 56.5% of that at 200 Hz), and Videomot was more accurate than manual analysis at 200 Hz. Values of the amplitude of lateral head displacement (ALH) were acceptable at most frame rates. At 〈 66.7 Hz the inclusion of spurious curvilinear track deviations caused lower mean ALH values, and at 5 Hz ALH could not be measured since the track was essentially the average path. Beat/cross frequency (BCF) was also frame rate dependent; at high rates there was the same problem as with ALH measurements, while at ≤ 25 Hz the maximum BCF was restricted by the frame rate. We conclude that human sperm movement characteristics can be measured at frame rates ca. 30 Hz but only if the constraints affecting VCL and BCF values are understood and accepted. Finally, 〈 10 Hz can only give values for VSL and, perhaps, VAP.
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  • 31
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    New York, NY [u.a.] : Wiley-Blackwell
    Clinical Anatomy 1 (1988), S. 285-294 
    ISSN: 0897-3806
    Keywords: gross anatomy ; pharynx ; human ; Life and Medical Sciences ; Miscellaneous Medical
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The pharyngeal raphe is described traditionally as a straight, continuous, median, fibrous band that provides attachment for and separates each pair of the three constrictor muscles of the pharynx. The posterior wall of the pharynx was dissected in 236 adult human cadavers of the Mongoloid, Caucasoid, and Negroid races. The arrangement of the raphe in each specimen was recorded. The various arrangements of the raphe were then organized into three types (I, II, or III) and eight subtypes (a, b, or c). The raphe was most often (47%) located between the inferior constrictor muscles only (type I) where it was either a straight or a curved line or had a fusiform to oval shape. The second most frequent pattern (40%) was a raphe located between the superior and middle constrictor muscles only (type II) with a shape similar to type I. The middle constrictor muscles were sometimes well developed and attached superiorly to the pharyngeal tubercle by way of a strong raphe. The raphe extended from the pharyngeal tubercle through all the constrictor muscles to the esophagus (type III) in only 13% of the specimens and was more often interrupted rather than a continuous line. The type usually described in anatomy textbooks (type IIIa) was found in only 5% of the specimens.
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  • 32
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    New York, NY : Wiley-Blackwell
    Gamete Research 18 (1987), S. 97-107 
    ISSN: 0148-7280
    Keywords: protein synthesis ; oocyte ; human ; electrophoresis ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: As a first step toward understanding control of gene expression in early human development, an analysis of protein synthesis and amino-acid transport in unfertilized mature oocytes was initiated. Qualitative patterns of protein synthesis were examined in individual oocytes cultured in medium containing radiolabeled methionine. No differences in synthetic pattern of proteins, resolved by one-dimensional electrophoresis and fluorography, were observed in oocytes analyzed from times varying from 12 to 52 hr following collection by laparoscopy. Contamination by follicular or corona radiata cells was readily distinguished on the basis of increased relative synthesis of a polypeptide with Mr = 44,000, a dominant product of synthesis in follicular cells. Based on the specific activity of the methionine precursor, the absolute rate of synthesis was measured to be about 50 pg/oocytc/hr, a value higher than in mouse unfertilized eggs. No difference in protein synthetic rate was observed in oocytes analyzed at 12 hr postcollection versus later times up to 50 hr postcollection. Competition of methionine uptake by leucine, efflux of radiolabeled methionine from preloaded oocytes into medium containing methionine and uptake of methionine in medium with low sodium ion concentration was observed. These findings are consistent with the presence of an L (leucine-preferring) system for neutral amino acid transport, similar to that in mouse and rabbit eggs. Total protein was measured to be about 150 ng/oocyte, a value five times that of the mouse. These studies provide basic data for further analysis of oocytes and perhaps preimplantation stage embryos in the future.
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  • 33
    Electronic Resource
    Electronic Resource
    Chichester [u.a.] : Wiley-Blackwell
    Developmental Genetics 8 (1987), S. 281-293 
    ISSN: 0192-253X
    Keywords: mouse ; human ; cow ; maps ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Technological advances in the 1970s encouraged the mapping of homologous gene loci in different mammalian species, including mouse and man. One hundred eighty-five homologous loci have now been mapped in these two species. Conservation of linkage is sufficient to identify substantial segments of the two genomes that have been left intact since their divergence from a common ancestor. The recognition of these conserved segments allows experimental manipulation of mouse chromosomes or chromosomal regions to produce models of human chromosomal anomalies of medical importance.Comparative gene mapping has been extended beyond mouse and man and the genomes of some species, including domestic cattle, appear to be more highly conserved relative to humans than the mouse. Such species may be particularly useful in providing models of human chromosomal anomalies that cannot be duplicated in laboratory mice.
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  • 34
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    New York, NY : Wiley-Blackwell
    Gamete Research 12 (1985), S. 85-89 
    ISSN: 0148-7280
    Keywords: spermatozoon ; cervical mucus ; human ; scanning electron microscope ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The ultrastructure of human cervical mucus was studied by scanning electron microscopy. In fertile women, naturally occurring midcycle cervical mucus showed an arrangement of parallel fibers oriented along the main axis of the mucus sample. Sperm migration through a column of cervical mucus in vitro was also studied. It was found that sperm present among the longitudinal fibers were oriented parallel to the them and to the main axis of the mucus sample.
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  • 35
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    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Bioelectromagnetics 6 (1985), S. 13-32 
    ISSN: 0197-8462
    Keywords: dosimetry ; electric field ; ELF ; 60 Hz ; human ; Life and Medical Sciences ; Occupational Health and Environmental Toxicology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Physics
    Notes: This paper gives current densities measured in homogeneous grounded human models exposed to vertical, 60-Hz electric fields. The methods used for these measurements were validated by measuring the current densities induced in a grounded hemisphere and in a grounded prolate hemispheroid; agreement between measurement and theory was good. For an unperturbed field strength of 10 kV/m, current densities measured in the human chest were in the range 125-300 nA/cm2. A strong horizontal current-density enhancement was observed in the axillae, with peak values of about 400 nA/cm2. The vertical current density in the arms, when held downward, was in the opposite direction to that in the chest. Current densities in the abdomen, pelvis, and legs were a strong function of whether the body was grounded through one or both feet. With one foot grounded, the horizontal current density in the lower pelvic region, just above the crotch, was 770 nA/cm2. This value was the largest of those measured in the head, arms, or torso of the human model. Scaling factors derived from these data and similar data for animals will provide a quantitative basis for comparing animal and human exposure to 60-Hz electric fields. In addition, current-density data given in this paper can be directly extrapolated to higher frequencies, at least to 1 MHz. These extrapolated data may be useful to individuals and groups involved in the determination of safety standards for the lower radiofrequency region.
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  • 36
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    New York, NY [u.a.] : Wiley-Blackwell
    Bioelectromagnetics 6 (1985), S. 33-40 
    ISSN: 0197-8462
    Keywords: human ; dosimetry ; safety ; radiofrequency ; Life and Medical Sciences ; Occupational Health and Environmental Toxicology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Physics
    Notes: Further studies of human whole-body radiofrequency (RF) absorption rates were carried out using a TEM-cell exposure system. Experiments were done at one frequency near the grounded resonance frequency ( ∼ 40 MHz), and at several below-resonance frequencies. Absorption rates are small for the K and H orientations of the body, even when grounded. For the body trunk in an E orientation, the absorption rate of a sitting person is about half of the rate for the same person standing with arms at the sides; the latter in turn is about half the rate for the same subject standing with arms over the head. Two-body interactions cause no increase in absorption rates for grounded people. They do, however, increase the absorption rates for subjects in an E orientation in free space; the largest interaction occurs when one subject is λ/2 behind the other (as seen by the incident wave). When these results are applied to practical occupational exposure situations, the whole-body specific absorption rate does not exceed the ANSI limit of 0.4 W/kg for exposures permitted by the ANSI standard (C95.1-1982) at frequencies from 7 to 40 MHz.
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  • 37
    ISSN: 0148-7280
    Keywords: human ; sperm ; zona pellucida ; zona-free hamster oocyte ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: In these experiments the mean number of sperm bound to the zonae pellucidae of immature human oocytes and to the vitelli of zona-free hamster oocytes were counted after centrifuging the oocytes through a discontinuous dextran gradient into a fixative. Sperm suspensions (107 sperm/ml) were preincubated in BWW medium containing 35 mg/ml of human serum albumin for 0 to 20 hr and coincubated with oocytes for 4 hr.The kinetics of sperm binding and sperm penetration were clearly different for the two types of oocytes in this system. Sperm binding to the zona pellucida appeared to be associated with zona penetration; when the zona was penetrated, many sperm were tightly bound and vice versa. A similar association between human sperm binding to the zonafree hamster oocyte and hamster oocyte penetration was not so apparent. Transmission electron microscopy revealed that all sperm which were “bound” to the hamster vitellus were acrosome reacted. On the surface of the human zona pellucida acrosome intact and acrosome reacted sperm were observed.These results suggest that tight binding of spermatozoa to the zona pellucida may be an important preliminary step in human fertilization. If this is true the activity of the sperm's “receptor for zona” may not be detected by the assay with zona-free hamster oocytes.
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  • 38
    ISSN: 0148-7280
    Keywords: sperm ; human ; zona pellucida ; cervical mucus ; zona-free hamster oocyte ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The functional capacity for sperm interaction with the human zona pellucida and zona-free hamster oocyte was tested after human spermatozoa were capacitated by passage through a column of human cervical mucus. The results were compared with those obtained when spermatozoa from an aliquot of the same semen sample were capacitated by the standard laboratory methods involving sequential washing by dilution and centrifugation of the semen. Washed-capacitated sperm suspensions were more successful than mucus-capacitated sperm in attaching to the zona-free hamster oocyte and in fusing with its oolemma. However, the ability of mucus-capacitated sperm to penetrate the human zona pellucida was equal to washed capacitated sperm. These experiments demonstrate an approach that may be useful in comparative studies of human sperm capacitation in vivo and in vitro.
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  • 39
    ISSN: 0148-7280
    Keywords: spermatozoa ; human ; motility ; activated motility ; hyperactivated motility ; capacitation ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Ten frames/sec microcinematography (“film”), 1 second timed-exposure photomicrography (“photo”), and laser Doppler velocimetry (LDV) were used to analyse the swimming patterns of human spermatozoa after migration (1 h at 37°C) into an overlying layer of either BWW or Menezo's B2 media. The upper layer of medium was carefully removed and further incubated at 37°C for either 4 h (B2) or 5 h (BWW) and the sperm motility analysed again. Five experiments were performed using semen from different donors. Film and photo analyses gave the relative incidence of nonprogressive and progressively motile spermatozoa plus, for the progressive spermatozoa, the velocities of progression (Vp) and amplitudes of lateral head displacement (Ah). LDV gave the percentage of motile spermatozoa and the modal instantaneous velocity (Vm). All postmigration sperm populations showed large significant increases in the percentage of motile spermatozoa, with good survival during incubation. The progressive postmigration spermatozoa generally moved with greater Vp and Ah than in the initial seminal plasma-diluted material; Vm was also increased. There were further increases in both Vp and Ah during incubation, but no change in Vm was detected. While the majority of spermatozoa were progressive, some showed a highly active pattern of movement which resulted in no net forward progression. The possible homology between these spermatozoa and the “hyperactivated” motility of capacitated spermatozoa in other mammalian species is discussed. Apparent discrepancies between the three methods used for motility analysis were seen, the possible causes and significances of which are also discussed.
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  • 40
    ISSN: 0148-7280
    Keywords: spermatozoa ; cervical mucus ; human ; motility ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Experiments were conducted to determine some of the biological variables that may affect sperm penetration of human cervical mucus in vitro. Quantitative tests of cervical mucus penetration were carried out to determine the percentage of successful collisons (PSC) between seminal spermatozoa and the semen-mucus interface. Fifteen duplicate comparisons and 15 triplicate comparisons of PSC values were made, each using individual samples of semen and mucus. In most cases the difference between any two comparisons was less than 10%, and there was no correlation between the magnitude of the difference between tests and the absolute value of the PSC. The triplicate comparison showed no correlation between the PSC values and the location of the mucus in the collection catheter (proximal, middle, distal). In 15 experiments the semen was serially diluted with an aliquot of its own plasma to determine the effect of sperm concentration on the PSC. No effects were observed until the sperm concentration fell below 10 × 106 sperm/ml, when the PSC appeared to increase. These results indicate that the tests should be applicable to all but the most severely oligospermic semen samples.
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  • 41
    ISSN: 0148-7280
    Keywords: nonovulatory follicle ; oocyte ; cumulus ; RNA ; protein ; human ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Human nonovulatory oocyte-cumulus complexes were obtained from large antral follicles 34 h after the injection of hCG. Their ultrastructure, RNA and protein synthesis, and the ability of oocyte maturation and subsequent fertilization in vitro were the subject of this study. The oocyte nucleus was situated in the cell periphery, possessing one or two dense nucleoli. Intranucleolar vacuoles were sometimes present. Mitochondria and smooth endoplasmic reticulum were the most abundant cytoplasmic structures. The number of cortical granules was rather low. Cumulus cells showed responsiveness to exogeneous hCG/endogeneous LH stimulation as morphologic signs of the oocyte-cumulus uncoupling and of the early luteinization. Furthermore, the oocytes were capable of meiotic maturation in vitro, and following subsequent in vitro insemination the majority of them were penetrated by spermatozoa. However, polyspermy was detected in most cases, and cleavage was not achieved. A developmental defect of nonovulatory oocytes was suggested by an extremely low level of RNA synthesis while continuing active protein synthesis by nonovulatory oocytes was demonstrated. In contrast, the associated cumulus cells synthesized both RNA and protein, suggesting that the majority of granulosa cells of the nonovulatory follicles was probably unaltered. It is hypothesized that the development of nonovulatory follicles after induction of ovulation might reveal the developmental pattern which would lead, in some cases, to ovulation of nonviable human oocytes both in stimulated and natural cycles.
    Additional Material: 12 Ill.
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  • 42
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Bioelectromagnetics 5 (1984), S. 131-146 
    ISSN: 0197-8462
    Keywords: human ; dosimetry ; safety ; radio frequency ; high frequency ; Life and Medical Sciences ; Occupational Health and Environmental Toxicology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Physics
    Notes: The radiofrequency absorption rates of five male human volunteers have been measured from 3 to 41 MHz. The subjects were exposed at about 10 μW/cm2 inside a very large transverse electromagnetic (TEM) cell and never absorbed more than 1 W. Both the EKH and EHK orientations were employed under both free-space and grounded conditions. Absorption rates for the EKH orientation exceed those of the EHK orientation by 40% in free space, but only by 6% when grounded. The absorption rates for the grounded men vary with frequency, f, as f1.9 from 3 to 25 MHz and then level off at the peak. The freespace absorption rates vary as f1.7 from 3 to 18 MHz and as f2.9 from 18 to 41 MHz. The average measured absorption rates at 10 MHz exceed the average of the standard model calculations by a factor of three (for free space) or four (grounded). The average man, when exposed grounded in an EKH orientation to the maximum permitted exposure levels under ANSI standard C95.1-1982, will absorb 0.58 ± 0.14 W/kg over most of the 3 to 41-MHz frequency range. This slightly exceeds the whole-body maximum of 0.40 W/kg underlying the standard.
    Additional Material: 5 Ill.
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  • 43
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Gamete Research 9 (1984), S. 175-181 
    ISSN: 0148-7280
    Keywords: human ; in vitro fertilization ; cleavage ; delayed insemination ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Two normal, healthy children have been born after an oocyte was collected from each of two patients during their natural menstrual cycle, incubated for many hours and then fertilized in vitro. Details of the follicular phase prior to oocyte recovery, fertilization and embryonic development in vitro, and replacement of the embryos are described in detail. One embryo cleaved rapidly after its delayed fertilization, with blastomeres of uneven size and cellular fragments. The luteal phase seemed to be weak in both patients.
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  • 44
    ISSN: 0148-7280
    Keywords: testis ; human ; spermatogenic cells ; two-dimensional electrophoresis ; marker proteins ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Highly homogeneous populations of human pachytene spetmatocytes and round spermatids have been obtained from normal adult testis using unit gravity (STA-PUT) sedimentation. Contaminating Leydig cells have been removed by density centrifugation in discontinuous Percoll gradients to yield resultant germ cell purities of 90-95% for pachytene spermatocytes and 89-96% for round spermatids. The total cellular polypeptide composition of separated human germ cells has been analyzed by two-dimensional polyacrylamide gel electrophoresis to compare 1) human and mouse pachytene spermatocytes (species specificity), 2) samples of human spermatocytes obtained from different individuals (allo specificity), and 3) pachytene spermatocytes and round spermatids from the same patients (stage specificity). Mouse and human germ cells have been found to exhibit extensive homology, but identified marker proteins limited to human spermatocytes include a group of polypeptides at p45/5.9 as well as a protein at p67/5.2. Proteins unique to mouse germ cells include component p65/5.5. Comparisons between different preparations of human pachytene spermatocytes have revealed about 90% electrophoretic homology, but some striking allotypic variations have been noted including the proteins at p45/5.9. Finally, presumptive stage-specific spermatogenic cell markers have been identified including the p45/5.9 polypeptides that are present only in human spermatocytes. Although the physiological roles of particular marker proteins have not yet been determined, the present findings indicate that purified spermatogenic cell populations may be analyzed biochemically to identify constituents important in the regulation of sperm development in man.
    Additional Material: 10 Ill.
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  • 45
    ISSN: 0148-7280
    Keywords: nucleolar structure ; RNA metabolism ; oocyte ; human ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Nucleolar ultrastrure was studied in fully grown human oocytes obtained from multilaminar preantral follicles and from follicles at different stages of antrum formation. Selective staining for ribonucleoproteins and 3H-uridine labeling were used in attempt to better understand the nature and functional significance of homogeneous dense nucleoli found in oocytes from large antral follicles.There was an apparent increase in the radio of nucleonema to nucleolar interstices, accompanied by a gradual degranulation of the nucleolonema during early stages of antrum fromation. The process of nucleolar homogenization continued in oocytes from medium-size antralfollicles, island of more tightly packed fibrils being hybothesized to represent persisting active transcription units. Entirely filamentous and homogeneous nucleoli were typical for oocytes from large antral follicles. They were demonstrated to ribonucleoprotein filaments embedded in pale- staining matrix. They were demonstrated to contain newly synthesized RNA after a 30-min pulse with 3H-uridine. The described nucleolar transformations are interpreted as acorrelate of nucleolar transition from a site of RNA synthesis into a site of RNA Storage during in human oocyte preovulatory development.
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  • 46
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Gamete Research 5 (1982), S. 153-160 
    ISSN: 0148-7280
    Keywords: zinc ; capacitation ; spermatozoa ; human ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The effects of zinc on human sperm motility, fertilizing capacity (as assessed by penetration of human spermatozoa into the zona pellucida-free hamster oocyte), and nuclear chromatin decondensation were investigated using spermatozoa from four fertile donors. Both sperm motility and the penetration of sperm into zona-free hamster ova were consistently impaired in media containing 1,000 μM zinc. Spermatozoa from one man were similarly affected at a concentration of 500 μM zinc, but no adverse effects were noted at this zinc concentration in experiments with other donors. Since decreased fertilizing capacity in response to zinc was always accompanied by a significant decline in both the percentage of motile cells and mean swimming speeds, it appears that all of these results reflect a general toxic effect on the cells. At lower concentrations (125-250 μM), zinc had no effect on human sperm motility nor their ability to undergo capacitation and penetrate zona-free hamster ova in vitro. For some donors, zinc (125-500 μM) stimulated both the attachment of spermatozoa to the hamster vitellus and the incorporation of spermatozoa into the hamster ooplasm. The decondensation of human sperm nuclear chromatin in sodium dodecyl sulfate was largely inhibited when zinc was added to the medium, but no significant changes in nuclear stability were apparent after capacitation in zinc-free medium. We conclude that zinc, when present in subtoxic concentrations, does not adversely affect the ability of human spermatozoa to undergo capacitation and penetrate zona-free hamster ova in vitro.
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  • 47
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Gamete Research 6 (1982), S. 81-89 
    ISSN: 0148-7280
    Keywords: adenylate cyclase ; spermatozoa ; calcium ; cyclic AMP ; human ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The adenylate cyclase activity of human ejaculated spermatozoa in broken-cell preparations was investigated. In the presence of 5 mM metal cations and 0.1 mM ATP, the relative enzyme activity with Mn2+, Ca2+, Mg2+, Ba2+ was 1.00, 0.28, 0.22, and 0.03, respectively. Added Ca2+ appeared to activate the enzyme in the presence of Mn2+ or Mg2+. The human sperm adenylate cyclase was stimulated by ∼ 2-fold by free Ca2+ (lmM) in the presence of Mg2+ (5 mM). If the GTP analogue, 5′-guanylyl imidophosphate (Gpp(NH)p) was added to the sperm homogenate in the presence of 200 μM ethylene-glycol-bis (β-aminoethylether) N,N′-tetraacetic acid (EGTA), the adenylate cyclase activity was increased by approximately 25%, but with the addition of 280 μM Ca2+ there was a decrease in enzyme activity. A similar response to low concentrations of Ca2+ was obtained after complementation of the sperm enzyme with the guanine nucleotide regulatory component from human erythrocytes, where the addition of 40 μM Gpp(NH)p, 200 μM EGTA, and Ca2+ (≤ 160 μM) stimulated the sperm enzyme ∼ 3-4-fold, but the further addition of Ca2+ (280 μM, final) neutralized the stimulatory effect. The addition of adenosine, and the nucleotides 5′-AMP and 5′-ADP inhibited the enzyme, whereas guanine and 5′-GMP had no appreciable effect. Human follicular fluid and serum also had little direct effect on the sperm adenylate cyclase. These resuls suggest that Ca2+ might be an important physiological modulator of the human sperm adenylate cyclase.
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  • 48
    ISSN: 0197-8462
    Keywords: microwaves ; infrared ; human ; thresholds ; Life and Medical Sciences ; Occupational Health and Environmental Toxicology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Physics
    Notes: Three male and three female adults individually placed the ventral surface of the right and upright forearm against a 15-cm-diameter aperture in a wall of microwave-absorbent material. Tensecond exposures occurred to E-vector-vertically polarized, 2450-MHz-CW microwave (MW) fields. Comparable exposure to infrared (IR) waves was repeated with four of the six observers. Thresholds of detection of just-noticeable warming by MW and IR radiation were determined by the double-staircase psychophysical method. Although the exposed surface areas of male observers' arm were larger than those of female observers, thresholds of warming by either source of energy overlapped; the pooled means of irradiance at threshold are 26.7 mW/cm2 (MW) and 1.7 mW/cm2 (IR). Dosimetric measures on saline models indicated virtually perfect absorption of the incident IR, but nearly two-thirds of the MW energy was scattered. Accordingly, the 15-fold difference in means of MW and IR thresholds resolves to a 5-fold difference in threshold quantities of absorbed energy. In the light of the high correlation between thresholds of IR and MW irradiation (r = .97), it is concluded that the same set of superficial thermoreceptors was being stimulated, only less efficiently so, by the more deeply penetrating, more diffusely absorbed MW energy.
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  • 49
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Gamete Research 5 (1982), S. 379-393 
    ISSN: 0148-7280
    Keywords: circular DNA ; spermatozoa ; human ; boar ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Circular DNA molecules were isolated from human and boar whole spermatozoa or spermatozoal nuclei and measured for size by electron microscopy. The DNA molecules derived from both mammals were heterogeneous in size ranging from 0.07 to 17 μm; nearly 75% of the molecules were ≤0.5 μm in length. The mean lengths were 1.0 μm and 1.5 μm for circular DNAs isolated from human and boar spermatozoa, respectively. The origin and function of these molecules remains unknown.
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  • 50
    ISSN: 0730-2312
    Keywords: T lymphocytes ; colonies ; in vitro ; human ; whole blood ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Growth of human lymphocyte colonies from whole blood following stimulation with PHA, Con A, or PPD is described. Individual colony cells were identified as T lymphocytes on the basis of surface marker and enzyme cytochemical characterizations. Colony formation increased as a power function over a wide range of cell concentrations above a critical minimal concentration. The whole blood culture system eliminates possible selective effects of lymphocyte colony techniques utilizing gradient-enriched lymphocyte fractions and more closely approximates the in vivo milieu. The whole blood colony method is more sensitive for the detection of low-level radiation effects on lymphocytes than widely used tests that measure 3H-thymidine incorporation. In preliminary studies, we used the whole blood method to determine the relative radiosensitivity of lymphocytes from humans with various hematopoietic disorders, and observed abnormalties in mitogen responsiveness and colony formation in some of the patient groups. This method has wide application for studies in cellular and clinical immunology.
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  • 51
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Gamete Research 4 (1981), S. 487-498 
    ISSN: 0148-7280
    Keywords: testis ; human ; cell separation ; germ cells ; spermatocytes ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Normal adult human testis has been separated using a combination of mechanical and enzymatic procedures to yield a suspension of viable single cells. The predominant cell types comprising this suspension are as follows: primary pachytene spermatocytes (7% of total cells), round spermatids (17%), residual bodies and condensing spermatids (31%), and Leydig cells (15%). Separated human germ cells viewed by Nomarski differential interference microscopy closely resemble mouse spermatogenic cells in relative size and appearance. Isolation of an enriched population of human pachytene spermatocytes has been achieved using unit gravity sedimentation (STA-PUT) according to protocols originally developed for murine tissue. Pachytene cells are enriched to 75% and are contaminated only with Leydig cells and binucleated spermatid symplasts. Ultrastructural examination of isolated human pachytene spermatocytes indicates that these cells, as well as isolated round spermatids, exhibit a normal in situ morphology. Spermatocytes, for example, show numerous synaptonemal complexes, nuclear pores, annulate lamellae, and dictyosome-like saccules. Round spermatids after isolation exhibit peripheral mitochondria, annulate lamellae, developing acrosomes, and other morphological features characteristic of early spermiogenesis. Therefore, enriched populations of human spermatogenic cells seem suitable for analysis using immunofluorescent, autoradiographic, or serological methods. In particular, isolated human spermatocytes should be useful for the analysis of molecular events involved in meiosis and should facilitate investigations concerning the pathophysiology of certain human infertility conditions.
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  • 52
    Keywords: HUMAN-CELLS ; analysis ; PHASE ; 3D ; FLUORESCENCE MICROSCOPY ; LIFE ; human ; CELL ; CELLS ; MICROSCOPY ; SEQUENCES ; SEQUENCE ; FLUORESCENCE
    Type of Publication: Book chapter
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