ISSN:0003-276X    

DOI:10.1002/ar.1091980102

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1980

数据来源: WILEY

摘要:

AbstractThe effect of hormones on developmental events is not a new area of scientific investigation. However, in the last decade, the developing lung has been the focus of an increasing amount of basic and applied research. Inadequate development of the newborn's respiratory system precludes extrauterine existence; indeed, such respiratory inadequacy has been a leading cause of death in premature infants. Tremendous strides have been made in understanding the basic cell biology of the developing lung. Much has been learned about the source, composition, and function of pulmonary surfactant, a surface‐active material produced by the lung and essential to alveolar stability. Deficient stores of this material is a major etiologic factor in the respiratory distress syndrome of the newborn (RDS). This fact, coupled with observations that certain hormones can accelerate lung development and the consequent availability of adequate stores of pulmonary surfactant, has led to a large body of literature dealing with the effects of hormones (and other agents) on lung development. It is the purpose of this literature review (1) to discuss the various kinds of investigations which have linked surfactant synthesis to the type II pulmonary epithelial cell; and (2) to review the current status of research dealing with the effects of glucocorticoids and thyroid hormons on lung maturatio

ISSN:0003-276X    

DOI:10.1002/ar.1091980103

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1980

数据来源: WILEY

摘要:

AbstractThe epithelium of the oviduct of the pig‐tailed monkey,Macaca nemestrinawas studied (1) to determine whether quantitative changes in the number of ciliated, deciliated, reciliating and nonciliated cells occur during the menstrual cycle and under certain experimental conditions and (2) to describe the ultrastructure of the ciliated and ciliogenic cells. The mean percentage of ciliated cells decreased from 48.2 in the fimbriae and 48.3 in the ampullae in the postovulatory stage to 7.7 and 18.8, respectively in the late luteal phase; these changes are significant as determined by Duncan's multiple range test. In the early follicular phase 3.9% of the cells in the fimbriae and 11.2% in the ampullae are ciliated, and the number of ciliogenic (deciliated and reciliating) cells is the highest of any time in the cycle in both the fimbrial (6.3%)and ampullar (8.4%)epithelium. In contrast, although the percentage of ciliated cells in the isthmus varies from 44.4 in the preovulatory phase to 34.3 in the early follicular phase, the differences between the various times in the cycle are not significant. However, in the late luteal phase, the values for the fimbriae and ampullae are significantly different from that of the isthmi. Ciliated cells constitute less than 1% of both the fimbrial and ampullar epithelium 2 ¾ years after ovariectomy, but 16.7 in the isthmic tissue. In ovariectomized monkeys treated for 7 or 12 days with estradiol benzoate reciliation occurs, but to a significantly lesser extent in the fimbriae and ampullae than in the pre‐ or postovulatory animals; the degree of reciliation in the isthmus is not different from the values noted during the cycle. The ultrastructure of ciliated, deciliated and reciliating cells is described. Of much interest is the finding of cytoplasmic protrusions containing variable numbers of ciliary axonemal complexes. It is postulated that such internalization of ciliary micotubules may represent one way in which deciliation may be accompli

ISSN:0003-276X    

DOI:10.1002/ar.1091980104

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1980

数据来源: WILEY

摘要:

AbstractIn all, 30 adult (45‐day‐old) Swiss Webster mice were used for light and electron microscopic examination of the presence, number, and location of adrenergic endings in the first molar teeth. Prior to sacrifice, 10 animals received i.p. injections at 8, 6, 4, and 2 hours of 0.5 cc of 20 mg/kg solution of 5‐hydroxydopamine (5‐OH‐DA) as a label for adrenergic endings. The animals were then anesthetized, perfused with Karnovsky's fixative, and the teeth were postfixed in Osmic acid, decalcified, embedded in methacrylate, and serial‐sectioned. The sections were surveyed by light microscopy, and the number and location of nerve endings containing the reduced 5‐OH‐DA were recorded. Ten control mice were injected with the vehicle solution and prepared in the same manner. A third series of mice were given a single injection of 5‐OH‐DA, sacrificed, and prepared for ultrastructural study. The molar pulps were divided into four areas to facilitate examination: pulp horns, coronal pulp, bifurcation area, and root pulp. These four areas were further divided into three zones: odontogenic, vascular‐related, and nonvascular‐associated. The location and number of endings were evaluated, and an average of approximately 70 endings containing the 5‐OH‐DA were found in each tooth using light microscopy. These represented 35.5 ± 5.2 in the pulp horns; 26.1 ± 2.4 in the central coronal; 5.4 ± 0.7 in the bifurcation, and 5.6 ± 0.9 in the root pulp per tooth. Vascular related endings were found in greatest number, the odontogenic zone next, and free endings least. Verification of location of 5‐OH‐DA by ultrastructural analysis revealed the false transmitter in vesiculated endings in t

ISSN:0003-276X    

DOI:10.1002/ar.1091980105

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1980

数据来源: WILEY

摘要:

AbstractInfant monkeys received 2 gm/kg body weight of aspartame (APM) or 2 gm/kg body weight APM plus 1 gm/kg body weight monosodium glutamate (MSG) by gastric tube. Blood samples were obtained at intervals over the ensuing 4 hours and analyzed for amino acid levels. At this time, each infant was perfused with glutaraldehyde. The hypothalamus was embedded in plastic and then serially sectioned at 1 μ.Hypothalamic morphology was normal in all eight infants given 2 gm/kg body weight APM and in the six infants given 2 gm/kg body weight APM plus 1 gm/kg body weight MSG. By light microscopy, no pycnotic nuclei, neuronal degeneration, or dendritic swelling was noted. In both experimental and control brains, localized areas of poor perfusion exhibited abnormal morphology. Elevated plasma levels of aspartate, glutamate, and phenylalanine indicated that the test compounds were administered and absorbed. Variable rates of absorption were evident, probably due to the necessity of administering APM as a slurry, due to its low solubility. On the basis of blood absorption curves, it appears that infant monkeys metabolize aspartate and glutamate and phenylalanine somewhat more rapidly than man.It is concluded that APM given alone or with MSG, in large acute doses, doesnotresult in hypothalamic damage in the newborn monkey

ISSN:0003-276X    

DOI:10.1002/ar.1091980106

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1980

数据来源: WILEY

摘要:

AbstractSkull measurements from ten anatomically and behaviorally diverse genera of bats show marked variation in positioning of the face upon the cranium but a relative stability of the site of the mandibular fossa. Factors associated with maintaining occlusion in bats which exhibit dorsally‐inclined maxillary toothrows include dorsally angulated mandibular bodies and elevated condyles. Detailed comparisons are made between the generalized morphology ofMyotis lucifugusand anatomical extremes represented byRhinolophus lepidus, Mormoops megalophylla, andPteropus giganteus. In these four bats, masticatory movements of the teeth and temporomandibular joints, despite marked interspecific variation, appear to relate to a common pattern. The beginning of jaw opening is important for maximal occlusal shear, particularly inPteropus. Observed differences in the histology of the temporomandibular joints reflect postulated differences of pressure patterns within them. Differences in skeletal and dental morphology, together with variations in size and orientation of masticatory muscles, could account for known and postulated differences in the four respective chewing patterns, with no major variation from the known muscle firing sequences ofMyotis lucifugus. Basic patterns of interaction between central nervous system and masticatory musculature would therefore appear to have undergone minimal modification. This accords with the concept that neural control of mastication is a relatively conservative mechanism; as such, it would appear to have imposed significant limitation upon adaptive change in bat

ISSN:0003-276X    

DOI:10.1002/ar.1091980107

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1980

数据来源: WILEY

摘要:

AbstractTo determine the morpholic changes in adrenocortices induced by chronic phenobarbital therapy, the male rats were orally administered the drug daily for varying periods up to three months. Fine structural changes attributable to the drug included mitochondrial pleomorphism and cavitation, loss of cholesterol ester clefts, reorganization of intracellular lipid, hypertrophy of the agranular endoplasmic reticulum and a juxtapositioning of the agranular endoplasmic reticulum, mitochondria and lipid droplets—all suggestive of an actively secreting cortex. The digitonin‐glutaraldehyde reaction suggested an active translocation of free cholesterol from lipid droplets to the mitochondria and agranular endoplasmic reticulum following phenobarbital treatment. Phenobarbital appears to stimulate corticosteroidogenesis due in large part to enhanced hepatic corticoid metabolizing enzy

ISSN:0003-276X    

DOI:10.1002/ar.1091980108

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1980

数据来源: WILEY

摘要:

AbstractRats bearing adrenocortical carcinoma 494 were injected daily for 7, 14, or 21 days with aminoglutethimide (AG) or o,p′‐DDD. Reversibility of these steroidogenic inhibitors was determined by injecting other animals for either 14 or 21 days and sacrificing them 14 days later. While the drugs had little effect on body or tumor growth, plasma corticosterone levels were reduced a maximum of 88% in normal and 95% in tumor‐bearing rats during AG chemotherapy. These levels were unaltered in normal rats by o,p′‐DDD and reduced a maximum of 64% in tumor‐bearing animals. Relative adrenal weights generally increased during chemotherapy and then returned to control levels. These changes were mainly due to alterations in the lipid and mitochondrial volume fractions. Lipid increased with both drugs while mitochondria increased with o,p′‐DDD and decreased with AG. Cholesterol ester levels paralleled the lipid stereology more closely with AG than o,p′‐DDD. With both drugs the most notable changes in tumor fine structure was a decrease in mitochondrial internal membranous vesicles and matrical density. Adrenal mitochondria had the irregular, elongated forms characteristic of tumor‐bearing animals and were vacuolated (AG) or had internal rings (o,p′‐DDD). The large lipid droplets observed during chemotherapy with both drugs were replaced by numerous small dro

ISSN:0003-276X    

DOI:10.1002/ar.1091980109

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1980

数据来源: WILEY

摘要:

AbstractPostcastrational adrenocortical carcinomas in the CE/Ki inbred strain of mice and the adrenals of noncastrated CE/Ki mice were studied using light and electron microscopic techniques. Most of the tumors appeared as large nodules of cells separated by septae comprised of collagen and blood sinusoids. The majority of tumor cells (Type 1) showed few or no lipid droplets (sudanophobic), polymorphic hyperchromatic nuclei, lack of SER, abundant RER and free ribosomes, prominent Golgi complexes, and few mitochondria with scant internal membranes. Clusters of Type 1 cells were surrounded by a basal lamina. In contrast, Type 2 cells revealed abundant and dilated tubules of SER, large number of lipid droplets and mitochondria with tubulovesicular cristae. These results suggest that Type 2 cells were probably active in steroid hormone synthesis and secretion while Type 1 cells were highly anaplastic and apparently non‐steroid‐secreting ce

ISSN:0003-276X    

DOI:10.1002/ar.1091980110

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1980

数据来源: WILEY

ISSN:0003-276X    

DOI:10.1002/ar.1091980101

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1980

数据来源: WILEY