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  • 1
    ISSN: 1471-4159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Abstract: The butyrophenone neuroleptics spiroperidol, benperidol, and haloperidol were radiolabeled with fluorine-18 and studied in baboon brain using positron emission transaxial tomography (PETT). Pretreatment of the baboon with a high pharmacological dose of (+)-butaclamol reduced the specifically bound component of radioactivity distribution in the striatum to approximately the radioactivity distribution found in the cerebellum. Comparative studies of brain distribution kinetics over a 4-h period indicated that either [18F]spiroperidol or [18F]benperidol may be suitable for specific labeling of neuroleptic receptors. In an 8-h study with [18F]spiroperidol, striatal radioactivity did not decline, suggesting that spiroperidol either has a very slow dissociation rate or that it binds irreversibly to these receptors in vivo. [18F]Haloperidol may not be suitable for in vivo PETT studies, because of a relatively high component of nonspecific distribution and a faster dissociation from the receptor. Analysis of 18F in plasma after injection of [18F]spiroperidol indicated rapid metabolism to polar and acidic metabolites, with only 40% of the total radioactivity being present as unchanged drug after 30 min. Analysis of the metabolic stability of the radioactively labeled compound in rat striatum indicated that greater than 95% of [18F]spiroperidol remains unchanged after 4 h.
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  • 2
    ISSN: 1432-086X
    Keywords: Key words: Pulmonary angiography—Percutaneous transbrachial approach—Catheters and catheterizations—Hydrophilic guidewire—Digital subtraction angiography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We have employed a new 4 Fr curved pigtail catheter with a hydrophilic-coated guidewire for transbrachial, selective pulmonary angiography using digital subtraction imaging. Eighteen patients and 27 pulmonary arteries were catheterized and selective pulmonary digital subtraction angiography was performed. Clinical diagnosis included lung cancer in 14 patients, thymoma in 1, bronchogenic cyst in 1, and pulmonary embolism in 2. Selective pulmonary arteriograms were obtained in all patients. No catheter-related complication occurred, although occasional premature ventricular contractions were noted. The high-flow injection rate of the contrast material resulted in clear visualization of the pulmonary arteries in all cases. This newly developed pigtail catheter combined with a hydrophilic-coated guidewire allowed easier and exact transbrachial selective pulmonary angiography to be performed. This technique does not require bedrest after the procedure and thus can be used in outpatients. It can also be used in patients who have thrombi along the transfemoral route.
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  • 3
    ISSN: 1520-4995
    Source: ACS Legacy Archives
    Topics: Biology , Chemistry and Pharmacology
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  • 4
    ISSN: 1520-4995
    Source: ACS Legacy Archives
    Topics: Biology , Chemistry and Pharmacology
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  • 5
    ISSN: 1573-4919
    Keywords: oxidative stress adaptation ; antioxidant reserve ; ischemia/reperfusion injury ; myocardial adaptation to ischemia ; endotoxin ; lipid A
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract Adaptation to various forms of stress has been found to be associated with increased cellular tolerance to myocardial ischemia. In this study, the effects of myocardial adaptation to oxidative stress was examined by injecting rats with endotoxin (0.5 mg/kg) and its non-toxic derivative, lipid A (0.5 mg/kg). Both compounds exerted oxidative stress within 1 h of treatment as evidenced by enhanced malonaldehyde formation. The oxidative stress disappeared steadily and progressively with time in concert with the appearance of the induction of glutathione and antioxidative enzymes that included superoxide dismutase, catalase, glutathione peroxidase and glutathione reductase. After 24 h of endotoxin or lipid A treatment, the amount of oxidative stress and antioxidant enzyme levels were significantly lower and higher, respectively, compared to those at the baseline levels. Corroborating these results, both endotoxin and lipid A provided protection against myocardial ischemia and reperfusion injury as evidenced by significantly improved postischemic recovery of left ventricular functions. The data presented here demonstrates that a controlled amount of oxidative stress induces the expression of intracellular antioxidants that can result in enhanced myocardial tolerance to ischemia. This suggests that myocardial adaptation to oxidative stress may be a potential tool for reduction of ischemic/reperfusion injury.
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  • 6
    ISSN: 1573-4919
    Keywords: nitric oxide ; carbon monoxide ; ischemia ; heart ; intracellular signaling ; cGMP ; SOD
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract To examine the intracellular signaling mechanism of NO in ischemic myocardium, isolated working rat hearts were made ischemic for 30 min followed by 30 min of reperfusion. A separate group of hearts were pre-perfused with 3 mM L-arginine in the presence or absence of 650 μM of protoporphyrin, a heme oxygenase inhibitor for 10 min prior to ischemia. The release of NO was monitored using an on-line amperometric sensor placed into the right atrium. The aortic flow and developed pressure were examined to determine the effects of L-arginine on ischemic/reperfusion injury. Induction for the expression of heme oxygenase was studied by Northern hybridization. For signal transduction experiments, sarcolemmal membranes were radiolabeled by perfusing the isolated hearts with [3H] myoinositol and [14C] arachidonic acid. Biopsies were processed to determine the isotopic incorporation into various phosphoinositols as well as phosphatidic acid and diacylglycerol. cGMP was assayed by radioimmunoassay and SOD content was determined by enzymatic analysis. The release of NO was diminished following ischemia and reperfusion and was augmented by L-arginine. L-arginine reduced ischemic/reperfusion injury as evidenced by the enhanced myocardial functional recovery. Protoporphyrin modulated the effects of L-arginine. cGMP, which was remained unaffected by ischemia and reperfusion, was stimulated significantly after L-arginine treatment. The NO-mediated augmentation of cGMP was reduced by protoporphyrin suggesting that part of the effects may be mediated by CO generated through the heme oxygenase pathway. Reperfusion of ischemic myocardium resulted in significant accumulation of radiolabeled inositol phosphate, inositol bisphosphate, and inositol triphosphate. Isotopic incorporation of [3H] inositol into phosphatidylinositol, phosphatidylinositol-4-phosphate, and phosphatidylinositol-4,5-bisphosphate was increased significantly during reperfusion. Reperfusion of the ischemic heart prelabeled with [14C] arachidonic acid resulted in modest increases in [14C] diacylglycerol and [14C] phosphatidic acid. Pretreatment of the heart with L-arginine significantly reversed this enhanced phosphodiesteratic breakdown during ischemia and early reperfusion. However, at the end of the reperfision the inhibitory effect of L-arginine on the phosphodiesterases seems to be reduced. In L-arginine treated hearts, SOD activity was progressively decreased with the duration of reperfusion time. The results suggests for the first time that NO plays a significant role in transmembrane signaling in the ischemic myocardium. This signaling appears to be on- and off- nature, and linked with SOD content of the tissue. The signaling is transmitted via cGMP and opposes the effects of phosphodiesterases by inhibiting the ischemia/reperfusion-induced phosphodiesteratic breakdown. Our results also suggest that NO activates heme oxygenase which further stimulates the production of cGMP presumably by CO signaling. Thus, NO not only potentiates cGMP mediated intracellular signaling, it also functions as a retrograde messenger for CO signaling in heart.
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  • 7
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Ubiquinones and Related Compounds, XXII1). - Synthesis of 2,3-Dimethoxy-5-methyl-1,4-benzoquinone and its Ethylhomologues2,3-Dimethoxy- (1a), 2,3-diethoxy-5-methyl- (1b), and 2,3-dimethoxy-5-ethyl-1,4-benzoquinone (12) are synthesized by oxidation of phenolic compounds or appropriate alkyl ethers with peracids. 3,4,5-Trimethoxy- (5a) and 3,4,5-triethoxytoluene (5b), which are obtained from gallic acid in relatively good yields, give 1a and 1b, respectively. 2,3-Dimethoxy-6-ethyl-phenol (11) and 2,3,4-trimethoxytoluene (13), which are synthesized from pyrogallol, give 12, 1a, and 2,6-dimethoxy-3-methyl-1,4-benzoquinone (14) in the same way. Intermediates and by-products of some reactions are isolated, and the reaction mechanisms are discussed.
    Notes: Durch Persäure-Oxydation geeigneter Phenole oder Alkyläther lassen sich 2.3-dimethoxy-(1a) und 2.3-Diäthoxy-5-methyl-1.4-benzochinon (1b) sowie 2.3-Dimethoxy-5-äthyl-1.4-benzochinon (12) darstellen. 3.4.5-Trimethoxy- (5a) und 3.4.5-Triäthoxy-toluol (5b), die aus Gallussäure mit relativ guten Ausbeuten dargestellt werden, ergeben dabei 1a bzw. 1b. 2.3-Dimethoxy-6-äthyl-phenol (11) und 2.3.4-Trimethoxy-toluol (13), welche, ausgehend von Pyrogallol, synthetisiert werden, ergeben ebenfalls 12 bzw. 1a und 2.6-Dimethoxy-3-methyl-1.4-benzochinon (14). Zwischenstufen und Nebenprodukte einiger Reaktionen werden isoliert und die Reaktionsmechanismen diskutiert.
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  • 8
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Ubiquinones and Related Compounds,XIII.EpoxyubiquinonesThe main ubiquinones found in the cells of Pseudomonas alkanolytica are 1a and 1b, their demethoxy (2a, 2b) and monoepoxy compounds (3a, 4a, 3b, 4b) are present as minor components (tab. 1). 3b was found to be a mixture of nine monoepoxy compounds of 1b, having the epoxide group at different positions in the isoprenoid side chain (chart 1, tab. 2, 3). Ubiquinone-10 (1c) and its analogous monoepoxy compounds 3c, 4c were obtained from the heart muscle of whale.
    Notes: Unter der Ubichinonen des Myzels von Pseudomonas alkanolytica sind 1a und 1b die Hauptvertreter, daneben kommen ihre Desmethoxy-Derivate 2a und 2b und ihre Mono-epoxide 3a, 4a, 3b und 4b vor (Tab. 1). 3b erwies sich als Gemisch der neun Mono-epoxide von 1b, deren Epoxid-Gruppe in verschiedenen Positionen der Isopren-Seitenkette liegen (Schema 1, Tabb. 2 und 3). Im Herzmuskel des Waltisches werden Ubichinon-10 (1c) und die analogen Mono-epoxide 3c und 4c aufgefunden.
    Additional Material: 4 Tab.
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  • 9
    ISSN: 1432-0878
    Keywords: Key words Nitric oxide synthase ; Oxygen-induced lung injury ; Pulmonary hypertension ; Rat (Sprague Dawley)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Breathing air with a high oxygen tension induces an inflammatory response and injures the microvessels of the lung. The resulting development of smooth muscle cells in these segments contributes to changes in vasoreactivity and increased pulmonary artery pressure. This in vivo study determines the temporal and spatial expression of endogenous endothelial nitric oxide synthase (NOS III) and inducible NOS (NOS II), important enzymes regulating vasoreactivity and inflammation, in the adult rat lung during the development of experimental pulmonary hypertension induced by oxidant injury. We analyzed the cellular distribution of these NOS isoforms, using specific antibodies, and assessed enzyme activity at baseline and after 1–28 days of hyperoxia (FIO2 0.87). The number of NOS III-immuno-positive endothelial cells increased early in hyperoxia and then remained high. By day 28, the relative number of these cells had increased from 40% in proximal vessels and 13–16% in distal alveolar vessels of the normal lung to 73–86% and 40–59%, respectively, in hyperoxia. Pulmonary alveolar macrophages (PAMs), normally few in number and only weakly immunopositive for NOS II or III in the normal lung, increased in number in hyperoxia and were strongly immunopositive for each isoform. These morphological data were supported by a temporal increase in total and calcium-independent NOS activity. Thus NOS expression and activity significantly increased in hyperoxia as pulmonary hypertension developed, and NOS III expression increased selectively in vascular endothelial cells, while both NOS isoforms were expressed by the PAM population. We conclude that this increase in expression of a potent vasodilator, an antiproliferative agent for smooth muscle cells, and an antioxidant molecule represents an adaptive response to protect the lung from oxidant-induced vascular and epithelial injury.
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  • 10
    ISSN: 1436-2813
    Keywords: mesenchymal chondrosarcoma ; rib tumor ; chest wall tumor ; adjuvant chemotherapy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Mesenchymal chondrosarcoma is a rare malignant cartilaginous tumor arising within the bone or soft tissue. An 18-year-old woman presented with a tumor on her left fourth rib. We performed a wide resection of the tumor and administered three cycles of postoperative adjuvant chemotherapy. Three years after the operation, the patient is alive without any evidence of either local recurrence or distant metastases. The findings of this case may thus support the usefulness of a radical resection and adjuvant chemotherapy for mesenchymal chondrosarcoma.
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