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  • Life and Medical Sciences  (11)
  • 1
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Cationized ferritin was used to analyze the surface charges on the luminal epithelial cell membranes of urinary bladders from toad (Bufo marinus), bullfrog (Rana catesbiana), turtle (Pseudemys scripta and Clemmys caspica), and tortoise (Geochelone carbonaria and Testudo graeca). The labeling, done at a physiological pH on fixed or unfixed bladders, revealed differences in the distribution and density of negative charges along the luminal membrane surfaces. The epithelial surface of toad bladder did not label with cationized ferritin. Frog bladder labeled lightly and the labeling pattern varied between cell types. The epithelial membrane surfaces of reptile bladders were heavily labeled, in contrast to amphibian bladders. Luminal surfaces from fresh water turtles were not as heavily labeled as those from land tortoises. The degree of labeling varied from cell type to cell type in all reptile bladders except Pseudemys scripta. An analysis of the degree and pattern of labeling by cationized ferritin in bladders of all species studied might reflect a difference in the nature of the glycocalyx of a particular membrane, the presence or absence of negative surface charges or their availability (i.e., interference by mucus), and/or the nature of the chemical groups comprising the surface structure of the membrane.
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The urinary bladder of the bullfrog, Rana catesbiana has been studied by light and electron microscopy. Three epithelial cell types were found: (1) granular cells, (2) mitochondria-rich cells, and (3) basal cells. The structure of the Rana catesbiana bladder differs from that of the toad Bufo marinus, in several respects: it lacks a mucous (goblet) cell type, its granular cells do not contact the underlying basement membrane, it has specialized, smooth-muscle cell-basal epithelial cell contacts, not previously described in amphibian bladders, and its mucosa is richly innervated. Mitochondria-rich cells within the bullfrog bladder epithelium were occasionally observed touching the basement membrane. The specialized smooth muscle-basal cell contacts provide anatomical evidence for how regulatory vasoactive substances such as neurohypophyseal peptides might alter epithelial geometry. Many nerve endings invest the mucosa just beneath the epithelial basement membrane in proximity to mitochondriarich cells and basal cells. The possible role of neural regulation in epithelial transport was discussed.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 192 (1978), S. 235-244 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The ability of the mammary gland to take up and organically bind radioiodide was studied in non-pregnant, pregnant, and lactating rats. Autoradiography was used to determine whether duct cells or alveolar cells are responsible for iodination in the rat mammary gland. Iodination was not detected in mammary glands from non-pregnant rats, but occurred late in the twelfth day of gestation and continued throughout pregnancy and lactation. Protein-containing vacuoles in alveolar cells and casein-like proteins in milk were the major sites where iodination occurred within the gland. Milk proteins in the lumens of ductules adjacent to alveoli were also iodinated. In contrast, ducts, myoepithelial cells, fat cells, blood vessels and other histological components of the gland did not show iodinating capability. Cytochemistry was also used to identify endogenous mammary peroxidase activity in the same glands, and it was found that the presence and location of this enzyme was correlated with the ability to iodinate.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 204 (1982), S. 323-332 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The purpose of this study was to determine by use of light- and electron-microscope autoradiography whether or not iodination occurred in mammary tumors of female GR mice. Of the sixty tumors studied it was found that pregnancy-dependent and hormone-induced tumors possessed iodinating ability. Although mammary glands from nonpregnant GR mice lacked the ability to iodinate, by the 16th day of pregnancy in response to hormonal stimulation the glands readily iodinated casein, and some epithelial cells contained ultrastructural cytochemical evidence of mammary peroxidase. Preneoplastic mammary gland lesions known as hyperplastic alveolar nodules were also able to iodinate, as were plaques, the disc-shaped lesions which give rise to the hormone-responsive mammary tumors in this strain. Plaques also contained epithelial cells with mammary peroxidase activity. When hormone-induced mammary tumors were transplanted into syngeneic mice they retained the ability to iodinate for several generations. However, as the tumors progressed to hormone independence, the ability to iodinate was gradually lost. Hormone-independent mammary tumors from GR mice lacked both iodinating ability and cytochemical evidence of mammary peroxidase. These findings suggest that iodination depends upon hormone-responsive cells within the mammary tumors and that as these cells become hormone unresponsive, the ability to iodinate is lost.
    Additional Material: 13 Ill.
    Type of Medium: Electronic Resource
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  • 5
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: An antibody to a protein produced by Clara cells in adult Syrian golden hamsters has been used to monitor the development and functional differentiation of secretory cells in the conducting airway epithelium of this species. Lungs from fetal and neonatal hamsters at gestational day 11 and at intervals up to and including 3.5 weeks of age (as well as adults) were studied. The earliest time this Clara cell protein could be identified by immunoperoxidase labeling in the fetal conducting airways was at gestational day 15. On this day, labeling was observed in a few secretory cells lining the trachea, in many lining the lobar bronchi, and in virtually all secretory cells lining the bronchioles. Ciliated cells and endocrine cells were not labeled. Granules first appeared within the apical cytoplasm of the secretory cells on gestational day 15 at all airway levels. To identify the exact subcellular location of this protein, an ultrastructural labeling procedure using protein A gold was employed. The gold particles labeled only electron-dense granules within the secretory cells, indicating that they represent the specific site of this protein. Since secretory cells in the most distal conducting airways began to produce this protein on the same day in development as cells in the larger airways, including the trachea, this expression of functional maturation occurs simultaneously throughout the conducting respiratory tree rather than proceeding sequentially in a cranial to caudal direction. Consequently, secretory cells lining the smaller conducting airways mature more rapidly than those lining the larger airways.
    Additional Material: 16 Ill.
    Type of Medium: Electronic Resource
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  • 6
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The conducting airway epithelium of fetal Syrian golden hamsters was studied from gestational day 12 to day 15, during normal and uncontrolled diabetic pregnancies. Diabetes was induced in the pregnant hamsters by injecting streptozotocin at 60 mg/kg body weight, subcutaneously, early on gestational day 10. Cells in S-phase were labelled immunochemically with bromodeoxyuridine (BrdU), and the day on which endocrine cells and ciliated cells first appeared was determined.In control fetuses, the BrdU-labelling indices (LI's) of different anatomical airway levels were significantly different from one gestational day to the next. For example, the LI of the lobar bronchus was significantly different on each gestational day (P.0001), and the same was true of the bronchioles. Moreover, the difference between LI's of the lobar bronchus and bronchioles-terminal buds was highly significant on day 12 (P 〈.0001), and on day 13 the differences between lobar bronchus and bronchioles, lobar bronchus and terminal buds, and bronchioles and terminal buds were also highly significant (P .0001). However, on gestational days 14 and 15, the LI's were reduced and were comparable at different airway levels. The BrdU-labelling indices were very consistent among fetuses of the same age, and the differences between the average LI's for pups of different litters was numerically very small.Hyperglycemia (mild, moderate, severe) did not alter LI's in the fetal airway epithelial cells. Furthermore, although glycogen was not depleted from the airway epithelium of the hyperglycemic fetuses as it was in the controls, the endocrine cells first appeared on gestational days 12, 13, and 14, respectively, in the trachea, lobar bronchus and bronchioles, followed 1 day later by the ciliated cells, in the fetuses of control and diabetic mothers. In our experimental model, induction of diabetes in the pregnant hamsters on gestational day 10 did not appear to alter development or diferentiation of the fetal conducting airway epithelium.
    Additional Material: 29 Ill.
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  • 7
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Urinary bladders from the desert tortoises, Testudo graeca and Geochelone carbonaria were removed at specific times during the year and studied by electron microscopy. Three epithelial cell types were found in both species in all bladders examined: (1) granular cells, (2) mitochondria-rich cells, and (3) basal cells. Cells analogous to these three types have also been observed in amphibian bladders (from to ad Bufo marinus and bullfrog, Rana catesbiana) and reptilian bladders (from Pseudemys scripta and Clemmys caspica). Both tortoises have an incomplete layer of basal cells so that the granular and mitochondria-rich cells extend from the lumen to the basement membrane: some thing not observed in bladders from bullfrog or turtles. A flask-shaped light cell was observed in the Geochelone carbonaria bladder obtained in April. No counterpart of this cell was seen in the same species sacrificed in January, or in any of the Testudo graeca bladders, although a similar cell has been described in the turtle, Pseudemys scripta (Rosen, Expt. Molec. Path., 12: 286-296, 1970). This study was undertaken to characterize the cell types present in tortoise bladder and to compare them with cell types in the bladder of the turtle, bullfrog and toad.
    Additional Material: 10 Ill.
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  • 8
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 228 (1990), S. 151-162 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Lectin binding was studied in the developing airways of Syrian golden hamsters on gestational days 11-16 (day 16 is the day of birth). The trachea and lungs were fixed in 4% formaldehyde-1% glutaraldehyde, 6% mercuric chloride-1% sodium acetate-0.1% glutaraldehyde, and 95% ethanol; embedded in paraffin; and stained with eight lectin-horseradish peroxidase conjugates: Triticum vulgare (WGA), Dolichos biflorus (DBA), Helix pomatia (HPA), Maclura pomifera (MPA), Griffonia simplicifolia I-B4 (GSA I-B4), Arachis hypogaea (PNA), Ulex europeus I (UEA I), and Limulus polyphemus (LPA). Each lectin yielded a characteristic staining pattern, which modulated throughout development. In general, changes in staining characteristics of the tracheal epithelium preceded similar changes in the lobar bronchus, bronchiole, and alveolus. In the case of UEA I, MPA, WGA, and HPA, staining increased with time uniformly over the luminal surface of all epithelial cells. However, in the case of PNA, GSA I-B4, and LPA, after the differentiation of ciliated and secretory cells, the apical surfaces of the ciliated cells stained more intensely than the apical surfaces of the secretory cells. Neuraminidase pretreatment enhanced PNA and GSA I-B4 staining in both cell types. In the case of PNA, these light microscopic observations were confirmed by ultrastructural study. Unlike the other lectins, the pattern of staining with DBA was unusual. Staining was moderate at first, then decreased (days 13 and 14), then increased at all airway levels. This study shows that different glycoconjugates modulate in airway epithelial cells throughout fetal development.
    Additional Material: 25 Ill.
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  • 9
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    American Journal of Anatomy 175 (1986), S. 35-48 
    ISSN: 0002-9106
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Explants of human breast (obtained aseptically from ten women ages 18-37) were examined and the vitamin A compound B-retinyl acetate was tested (at 3 × 10-5 and 3 × 10-6 M) for its effects on the fine structure and growth of the epithelium. In the absence of B-retinyl acetate, cells growing out from the explant (outgrowth cells) underwent squamous metaplasia, began to accumulate many intermediate filaments (tonofilaments), and revealed large desmosomes after 2 weeks in culture. In the presence of either concentration of B-retinyl acetate, the epithelial cells were largely prevented from undergoing squamous metaplasia. The glandular epithelium inside the explant maintained a typical secretory appearance for 2 weeks in control cultures (without the retinoid) and then began to show increased numbers of lysosomes and a loss of secretory granules. These glandular epithelial cells did not undergo squamous metaplasia, but they contained increased numbers of intermediate filaments. In contrast, glandular epithelium cultured in either concentrations of B-retinyl acetate appeared secretory for as long 6 weeks in culture, and intermediate filaments were not obvious. Autoradiographs demonstrated that both concentrations of B-retinyl acetate inhibited cell division in the outgrowth epithelium and in the (internal) glandular epithelium. The ability of B-retinyl acetate to reverse squamous metaplasia in the outgrowth cells was also tested. Out growth cells reversed to a more normal ductlike appearance after 6 weeks culture in standard medium followed by only 1 week in 20 μg/ml B-retinyl acetate. After 7 weeks in standard medium and 1 week in 10 μg/ml B-retinyl acetate, the cells showed a partial reversal of the squamous metaplasia.
    Additional Material: 13 Ill.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    American Journal of Anatomy 156 (1979), S. 169-181 
    ISSN: 0002-9106
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Thyroid glands from female rats kept vitamin A deficient for one, two, and three months were examined by electron microscopy. After one month on the diet, no consistent alterations were noted. After two months, the colloid in some follicles displayed a peripheral zone of decreased density. In addition, ultimobranchial follicles within the gland had become keratinized. After two to three months on the diet, cells were seen entering the colloid. Many of these cells were identified as follicular cells since they often occurred in groups and occasionally exhibited remnants of desmosomes. Often the cells within the colloid appeared vacuolated, and by light microscopy were thought to contain lipid. However, electron microscopy revealed that these cells contained many digestive vacuoles rather than lipid droplets.Quantitative and autoradiographic studies indicated that thyroids of vitamin A deficient rats took up less radioiodide than thyroids of control rats. The keratinization of ultimorbranchial follicles in vitamin-A deficiency has been suggested as preliminary in the histogenesis of squamous cell carcinoma. However, an effect of vitamin A deficiency on thyroid follicular cells has not heretofore been reported. It's possible that the presence of follicular cells in the colloid reflects an accelerated turnover of these cells and could indicate an early pathological sign.
    Additional Material: 1 Tab.
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