Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
Collection
Publisher
  • 1
    ISSN: 1432-119X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé Les techniques d'immunofluorescence, d'immunoenzymatique, d'imprégnation ou de coloration sélective des cellules endocrines digestives, et de microscopie électronique ont été combinées pour permettre l'identification et l'étude des cellules à somatostatine chez des animaux normaux ou ayant reçu de la L-Dopa. Ces cellules n'ont pas de fluorescence induite à la formaldéhyde et ne sont que très faiblement argyrophiles en technique de Grimélius; elles ne réagissent pas en technique de Sevier-Munger, Hellerström-Hellman, Mac Conaill. Après administration de L-Dopa elles acquièrent und fluorescence (cellules GIC) et deviennent nettement argyrophiles en technique de Grimélius, plus faiblement en technique de Sevier-Munger. En microscopie électronique après identification immunologique sur coupe semi-fine on peut analyser les mêmes cellules sur coupes fines. Il s'agit de cellules basigranuleuses présentant, outre des grains denses difficiles souvent à distinguer de ceux des cellules G, trois structures fines caractéristiques par leur constance et leur coexistence; ce sont: des grains peu denses et homogènes—des graïns centrés par un matériel filamenteux grossier—des microfilaments nombreux. Les cellules à somatostatine semblent différentes des cellules X et D1.
    Notes: Summary In normal and L-Dopa treated rabbits and mice, combined immunochemical methods, photonic histological methods for endocrine cells and ultrastructural methods were used to elucidate ultrastructure and properties of somatostatin cells of the antral mucosa. In normal rabbits, immunoreactive cells giving no fluorescence with Falck's technic, they corresponded neither to serotonin cells nor gastrin cells; they were unreactive with Fontana, Hellerström-Hellmann, Sevier-Munger and Mac Conaill methods but very slightly stained with Grimelius methods. In L-Dopa treated animals somatostatin cells gave formaldehyde induced fluorescence (they were included in GIC cells, thus in Apud group), exhibited a good reaction with Grimelius and Sevier-Munger methods. In order to carry out the alternate semi-thin/thin section procedure (semi-thin sections for immunofluorescence or immunoenzymatic detection and serial thin sections counterstained for conventional ultrastructure studies), immunological treatment were performed on M.F.F.—glutaraldehyde fixed small fragments of mucosa before inclusion in Epon 812 or, after inclusion, on semi-thin sections. We succeeded in identifying ultrastructurally somatostatin cells. They displayed round or ovoïd shaped secretory granules, and three constant typical structures: numerous microfilaments—light and homogenous granules, often seeming like lipids—granules made up by coarsely filamentous cores surrounded by a large empty halo. Somatostatin cells seemed different of X cells because of their predominant localisation in the antral mucosa (in the rabbit X cells were predominantly in the fundus) and because of the lack of nuclear microfilaments; they also seemed ultrastructuraly different of D1 cells.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1432-119X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé La conservation in vitro durant trois jours de fragments de muqueuse intestinale de foetus de Lapin induit une dégénérescence épithéliale suivie d'une régénération. Dans l'épithélium en régénération des cellules endocrines se différencient; leurs caractères cytochimiques sont analysés en comparant les images obtenues sur une même coupe à l'aide de techniques différentes. II apparaît que les cellules à sérotonine acquièrent successivement les caractères suivants: fluorescence induite par la formaldéhyde puis argyrophilie et colorabilité à l'hématoxyline plombique puis argentaffinité. In vivo fluorescence et argyrophilie apparaissent simultanément. Cette chronologie apporte de nouveaux critères pour l'étude de la différenciation. In vitro la présence de sérotonine ne confère donc ni argentaffinité ni même argyrophilie. L'hypothèse d'un stockage hyaloplasmique de l'amine dans les premiers stades de la différenciation est envisagée.
    Notes: Summary Ontogenic differentiation of intestinal serotonin cells of 22 days old rabbit fetuses were studied in vitro. After 3 days of organotypic cultivation in solid medium, a great part of epithelial cells became necrotic and were eliminated into the lumen while a first flattened, then cuboidal, then prismatic new growed epithelium in which FIF indicated some serotonin cells was present. Comparison of pictures obtained on the same slide by different methods was used in order to estimate correspondances between amine storage, argentaffin, argyrophilic and reductive properties. A new phase in serotonin cell differentiation was readily distinguished since young cells successively yelded FIF, later argyrophilia, later argentaffinity. These datas, at variance with that occurs in vivo where FIF and argyrophilia appeared simultaneously, give a new criteria for differential mechanism studies, disprove the theory of an amine induced argyrophilia and enhance the hypothesis of a hyaloplasmic amine storage in very young cells.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1432-119X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé Si chez des animaux intacts ou ayant reçu de la L-Dopa on compare les images d'une même coupe traitée d'abord selon Falck, ensuite colorée ou imprégnée selon divers procédés, on peut constater les faits suivants: la formaldéhyde confère une fluorescence jaune terne (Jt) à des cellules GIC dépourvues d'argyrophilie selon Sevier et Munger mais imprégnées en technique de Grimélius, colorées par le picroponceau et l'hématoxyline au plomb. Il y a approximativement trois fois plus de cellules imprégnées selon Grimélius que de cellules fluorescentes; parmi elles 1/3 environ réagit fortement en technique de Sevier et Munger (cellules à sérotonine), 1.3 réagit faiblement (cellules SM), 1/3 ne réagit pas du tout (cellules D et Jt). Les cellules SM correspondent aux «ECL cells» bien que dépourvues d'amine et d'argentaffinité (Fontana-Masson); elles se divisent en GIC et non GIC, les premières sont ou non colorables par l'hématoxyline au plomb, les secondes ne le sont pas.
    Notes: Summary Whether the same endocrine like cells are reactive towards different staining reactions has been hardly examined in normal and L-Dopa treated rabbits for distinction of cell types. Samples were first freeze-dried, exposed to formaldehyde vapours (standard Falck technic) and sections photographied. Thereafter they became further hydrated and were stained with silver according to Fontana-Masson or Grimelius or Sevier-Munger, or with ferric ferricyanide or lead hematoxylin or picroponceau. Formaldehyde condensation induced a bright yellow fluorescence in serotonin cells and revealed a dim yellow (jaune terne: Jt) unexpected fluorescence in others scarce cells. The laters were non argentaffin, unreactive with Sevier-Munger method but argyrophilic in Grimelius technic, stained blue black by lead hematoxylin and red by picroponceau; there are a part of the GIC or APUD cells group. Grimelius reaction stained three times as many cells as fluorescence did. With Sevier-Munger method, heavily darkened (serotonin cells), slightly reactive (Sevier-Munger or SM cells) and unreactive cells (D and Jt cells) roughly represented 1/3 each of all Grimelius positive cells. ECL cells according to Capella et al. (1969) apparently corresponded to SM cells; since all fluorescent cells are strongly argentaffin and reactive with Sevier-Munger method, since they are too much scanty to include EC and ECL cells it is conclude that ECL cells failed to exhibit fluorescence and to store serotonin: furthermore taking hypothetically ECL cells into fluorescent cells it would imply to blend D cells and SM cells which is at variance with earlier observations of unreactivity of D cells in Sevier-Munger technic at the ultrastructural level. SM cells population seemed heterogenous: only some of them were GIC and only some of the laters were stained by lead hematoxylin; however it is not clear how much the L-Dopa administration effect the second staining possibly causing erroneous reactions.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 1432-119X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé Les «enterochromaffin cells» de type III (Håkanson et al., 1970) sont ici étudiées chez des lapins intacts ou ayant reçu de la L-Dopa. La comparaison des images obtenues par traitement des mêmes coupes d'abord en technique de Falck, ensuite par imprégnation selon Fontana ou Grimélius ou Sevier et Munger, ou coloration au ferricyanure ferrique on à l'hématoxyline au plomb font apparaître les caractères suivants: chez les animaux intacts les cellules vert-pâle ne sont ni argentaffines ni argyrophiles en technique de Sevier et Munger; elles se laissent imprégner selon la méthode de Grimélius; elles ne sont colorées ni par le ferricyanure ferrique ni par l'hématoxyline au plomb. Après administration de L-Dopa les cellules ayant capté et décarboxylé le précurseur (cellules GIC) ne réduisent ni l'argent ni le ferricyanure ferrique et sont argyrophiles en technique de Grimélius; certaines seulement deviennent argyrophiles en technique de Sevier et Munger ou se colorent par l'hématoxyline au plomb. Compte tenu des analyses de la microscopie électronique l'emplacement de ces cellules, leur nombre et leurs affinités tinctoriales permettent de les assimiler aux cellules G ou cellules à gastrine. Les variations observées après L-Dopa témoignent soit de la diversité des types cellulaires soit de l'interférence de ce précurseur dans le cycle sécrétoire des cellules d'une même catégorie.
    Notes: Summary In normal and L-Dopa treated rabbits enterochromaffins cells type III, according to Håkanson et al. (1970–1972) have been analysed histochemically, using freezedried specimens first treated with formaldehyde vapours (standard Falck technique) and photographied, then stained with silver according to Fontana-Masson or Grimelius or Sevier-Munger or with ferric ferricyanide (Adams) or lead-haematoxylin (MacConaill). In non-treated animals greenish fluorescent cells were unreactive with Fontana-Masson and Sevier-Munger methods, unstained by ferric ferricyanide and lead haematoxylin but reactive to the Grimelius silver technique, with a regular correspondance between fluorescent and argyrophilic intensities. In L-Dopa treated animals GIC cells («cellules gastrointestinales captantes» or “APUD cells») exhibited a strong green fluorescence and initially poor greenish fluorescent cells become undistinguishable from others eventual GIC cells. All remained non argentaffin and failed to react with ferric ferricyanide; all were stained with Grimelius method but correspondance between fluorescent and argyrophilic intensities were so fairly inconstant that a few argyrophil cells were seen devoid of fluorescence. Some of GIC cells were more or less reactive with Sevier-Munger silver technique or with lead haematoxylin. From these data it can be concluded: 1. That enterochromaffin and enterochromaffin like are improper terms because these cells did not posses corresponding specific properties (serotonin or dopamine storage and argentaffinity for enterochromaffin cells, unreactivity by fluorescence microscopic procedure of Falck for enterochromaffin like cells); «GIC cells» or «APUD cells» are more accurate terms. 2. That having in mind the distributive pattern of ultrastructurally identified G cells, the number and histochemical properties of cells reputed to produce gastrin, observations reported here clearly support the hypothesis that greenish GIC cells are G cells. 3. That staining intensity variations with Sevier-Munger method or lead haematoxylin in treated animals may be dealing with either an heterogenous GIC population or an effective influence of the amine precursor on secretory cycle of a single cell type.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 5
    ISSN: 1432-1203
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Allotypes of IgG1, IgG2, IgG3, and IgA2 subclasses were investigated in seven Lebanese communities (three Moslem and four Christian). The Gm-Am haplotypes found were mainly those prevalent in Caucasians with a low frequency of haplotypes usually observed in Africans and Orientals. The difference between highlanders and lowlanders as expressed by G2m(23) was highly significant and suggested a possible adaptation to selective pressure related to the γ2 genes, possibly due to endemic malaria in the past. Exceptional Gm-Am haplotypes were unambiguously determined by family studies. Some were characterized either by a deletion or a repression or, in contrast, by a partial or total duplication of γ genes. Two others had uncommon combinations of allotypes: Gm 17;23;5,10,11,13,14 A2m 1, where G1m(17) was present without G1m(1); and Gm 3;23;5,14 A2m 1, where the CH3 allotypes G3m(10,11,13) were lacking.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 6
    ISSN: 1432-1211
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The five humanIGHG genes consist of three constant domain exons plus one of or four hinge exon(s), the quadruplicated hinge region being characteristic of theIGHG3 gene. Besides this structural difference, theIGHG genes are polymorphic, as demonstrated by the restriction fragment length polymorphism and, at the protein level, by the Gm allotypic antigenic determinants. In this paper, we report the sequence of theG3m(b0, b1, c3, c5, u) IGHG3 allele, typical of the Black African populations and of populations with Negroid admixture, found in a homozygous Tunisian designated as LAT. We demonstrate that thisG3 allele contains only three hinge exons instead of four (the probable result of an unequal crossing over) and thatIGHG3 genes with triplicated hinge exons (and therefore encoding shorter γ 3 chains) are present in healthy individuals from different populations. Moreover, we show that the LAT G3m (b0, b1, c3, c5, u) coding sequence results from the conversion, in the CH3 exon, of theG3m (b0, b1, b3, b4, b5, u, v) allele, the most frequentIGHG3 gene in the Negroid populations, by the homologous region of aIGHG4 gene. The structural features of theLAT IGHG3 allele, which are the lack of one hinge exon and its conversion by theIGHG4 gene, demonstrate that both crossing-over and gene conversion events occur in the evolution of the humanIGHG genes.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 7
    ISSN: 1432-1203
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Molecular characterization of a ring chromosome 14 was carried out in a patient with the 46,XX,r(14) karyotype. The breakpoints shown by chromosome banding were within bands p11 and q32. Using molecular probes for the immunoglobulin heavy chain (IGH), D14S1 and PI loci located at 14q32, we showed that the IGH and D14S1 loci, located at 14q32.2 and 14q32.2, respectively, were deleted on the ring chromosome 14, but that the PI locus was not. Therefore, the chromosomal break lies between PI and D14S1. These results show that the order of these chromosome 14 markers is cen-PI-D14S1-IGH, in keeping with multipoint linkage data. Further molecular characterization of ring 14 chromosomes should lead to a detailed understanding of the molecular events and clinical consequences of the gene deletion associated with such chromosomal aberrations.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 8
    ISSN: 1432-1203
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Hypohaptoglobinaemia and ahaptoglobinaemia occurred in three generations, mainly to male members of a family. Also small amounts of haptolobin were detected in most of the female relatives. Haemolytic anaemia seemed unlikely and the glucose 6 phosphate dehydrogenase (G.6.P.D.) activity was normal. The probable genotype of these apparently healthy individuals was Hp 2/Hp 2. These preliminary data might suggest a defect in control of gene expression by steroid hormones.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 9
    ISSN: 1432-1203
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. An analysis of 11 Alu insertion polymorphisms (ACE, TPA25, PV92, APO, FXIIIB, D1, A25, B65, HS2.43, HS3.23, and HS4.65) has been performed in several NW African (Northern, Western, and Southeastern Moroccans; Saharawi; Algerians; Tunisians) and Iberian (Basques, Catalans, and Andalusians) populations. Genetic distances and principal component analyses show a clear differentiation of NW African and Iberian groups of samples, suggesting a strong genetic barrier matching the geographical Mediterranean Sea barrier. The restriction to gene flow may be attributed to the navigational hazards across the Straits, but cultural factors must also have played a role. Some degree of gene flow from sub-Saharan Africa can be detected in the southern part of North Africa and in Saharawi and Southeastern Moroccans, as a result of a continuous gene flow across the Sahara desert that has created a south-north cline of sub-Saharan Africa influence in North Africa. Iberian samples show a substantial degree of homogeneity and fall within the cluster of European-based genetic diversity.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 10
    ISSN: 1432-1203
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Two cases of chromosome 14 rearrangements with partial duplication which occurred de novo were analyzed by Southern blot analysis using IGH, D14S1 and PI probes. In the first case, with a 46,XX,14p+ karyotype, our study confirms that the additional material on chromosome 14p+ results from a duplication of the 14q region containing the IGH, D14S1 and PI loci. In the second case, our study reveals only one 14q32 locus per chromosome 14 indicating that the extra material does not contain the 14q32 region. Our results demonstrate that molecular probes of the 14q32 region are valuable tools for the characterisation of chromosome 14 abnormalities appearing de novo.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...