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1.
Immunocytochemical characterization of several epithelial markers using the PAP technique was analyzed during different stages of induced prostatic hyperplasia in rats. Intact adolescent rats (42 days old) were treated with citral (3,7 dimethyl-2,6 octadienal) for 10, 30 and 100 days and their ventral prostate compared to untreated, matched-age animals. Among the epithelial markers studied the prostatic specific acid phosphatase was present in hyperplastic prostates of rats. The immunoreaction showed a fair correlation with the severity of lesion and duration of treatment. The prostatic specific antigen showed equally immunoreactive in both control and treated rats. The hyperplastic and normal rat prostates did not show immunoreactivity towards the other epithelial cell markers such as epithelial membrane antigen, carcinoembrionic antingen and alpha-fetoprotein antisera. It is concluded that prostatic specific acid phosphatase, and to a lesser extent prostatic specific antigen, might represent valuable markers for comparative studies of prostatic hyperplasia in rodents.  相似文献   
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Summary A strain of Balb/c mice with neurovisceral storage disorder exhibits metabolic and phenotypic manifestations similar to those found in Niemann-Pick type C and D patients. The storage material in the brain reacted positively with periodate-Schiff reagent. To identify the chemical nature of the storage material we applied lectin histochemistry on paraffin-embedded and frozen sections, using biotinylated lectins and avidin-biotin-peroxidase complex. Major abnormalities were noted in the neurons and glia cells. Swollen neurons were stained heavily by Con A and S-WGA, whereas glia cells, mainly astrocytes, which were abundant both in the cerebrum and cerebellum, were positive to RCA-I, GS-I, PNA, S-WGA and WGA. The myelin tracts reacted with PNA, SBA and RCA-I but to a lesser extent in affected animals when compared to normals.Frozen brain sections stained positively only after extraction with chloroform methanol prior to the lectin treatment and revealed a lectin binding pattern similar to that of the paraffin-embedded preparations. The data presented here show that the stored glucoconjugates in the neurons are of a different chemical composition than those found in glia cells. Since only paraffin embedded sections or lipid extracted frozen sections reacted with the lectins, we suggest that the stored glucoconjugates are glycoproteins or oligosaccharides rather than glycolipids.  相似文献   
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Immunohistochemical approach to the study of the cat carotid body   总被引:2,自引:0,他引:2  
The mammalian carotid body contains a number of different cell types which are not always easy to identify in routine histological sections. We have devised a battery of immunohistochemical tests which overcome this difficulty and offer the possibility of performing routine morphometric analyses of the response of the organ to various pathological processes in paraffin-embedded sections. The type 1 cells can be identified on the basis of their reaction with neuronal specific enolase, whilst type II cells react with antibodies to S-100 protein. Schwann cells do not react with S-100 antibodies but do so with antibodies to glial fibrillary acidic protein; nerve fibres can be identified by their reaction to neurofibrillary protein.  相似文献   
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Administration of STZ prior to mating, induced significant impairment in glycogen metabolism in term rat placentae. Glycogen retention was observed in the treated placentae, while glycogen synthetase activity was reduced. The glycogenolytic pathway seemed to proceed mainly through amyloglucosidase enzyme whose activity increased threefold. Glucose-6-phosphatase showed a moderate activation, mainly in the labyrinth zone, while phosphorylase was slightly inhibited. These changes were accompanied by a decrease in placental insulin levels. The possible defensive role played by the placenta in cases of maternal hyperglycemia was postulated.  相似文献   
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Neurochemical Research - Acrylamide (ACR) is an environmental pollutant with well-demonstrated neurotoxic and neurodegenerative effects in both humans and experimental animals. The present study...  相似文献   
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The broad spectrum of health benefits attributed to probiotics has contributed to a rapid increase in the value of the probiotic market. Probiotic health benefits can be strain specific. Thus, strain-level identification of probiotic strains is of paramount importance to ensure probiotic efficacy. Both Lactobacillus gasseri BNR17 and Lactobacillus reuteri LRC (NCIMB 30242) strains have clinically proven health benefits; however, no assays were developed to enable strain-level identification of either of these strains. The objective of this study is to develop strain-specific PCR-based methods for Lactobacillus gasseri BNR17 and Lactobacillus reuteri LRC strains, and to validate these assays according to the guidelines for validating qualitative real-time PCR assays. Using RAST (Rapid Annotation using Subsystem Technology), unique sequence regions were identified in the genome sequences of both strains. Probe-based assays were designed and validated for specificity, sensitivity, efficiency, repeatability, and reproducibility. Both assays were specific to target strain with 100% true positive and 0% false positive rates. Reaction efficiency for both assays was in the range of 90 to 108% with R square values > 0.99. Repeatability and reproducibility were evaluated using five samples at three DNA concentrations each and relative standard deviation was < 4% for repeatability and < 8% for reproducibility. Both of the assays developed and validated in this study for the specific identification of Lactobacillus gasseri BNR17 and Lactobacillus reuteri LRC strains are specific, sensitive, and precise. These assays can be applied to evaluate and ensure compliance in probiotic products.

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Background & objectivesRosuvastatin calcium (RC) is a potent and competitive synthetic inhibitor of HMG-CoA reductase used for the treatment of dyslipidemia. Guggulipid obtained from Commiphora mukul is used in the treatment of a wide variety of diseases such as atherosclerosis, hypercholesterolemia, rheumatism, and obesity. The present study evaluates the pharmacokinetic and pharmacodynamic interactions between RC and the standardized guggulipid extract in rats.Materials and methodsThe guggulipid extract was standardized for the presence of guggulsterones. The pharmacokinetic interaction was determined after a single dose administration of RC alone or in combination with the guggulipid extract or after multiple-dose administration of RC alone or RC along with the guggulipid extract for 14 days. To determine the pharmacodynamic interaction, RC and guggulipid extract were administered to hyperlipidemic rats for 14 days. The level of significance was determined using unpaired student’s t-test, one way ANOVA, the post-ANOVA Tukey test.ResultsStandardization of guggulipid extract showed it contains 7.5%w/w of guggulsterones. Guggulipid extract increased the bioavailability of RC in both single-dose and multiple-dose studies. Guggulipid extract reduced the rate of absorption (Ka) of RC but showed an increase in maximum serum concentration (Cmax). An in-vitro study using isolated rat intestine revealed that guggulipid extract decreased the rate of absorption of RC in the intestinal lumen. The hypolipidemic activity of RC was augmented by the guggulipid extract in hyperlipidemic rats.Interpretation & conclusionTherefore it is concluded that guggulipid extract increases the bioavailability of RC by delaying its Ka and augments its hypolipidemic action. However, it is recommended that a combination of RC with guggulipid extract should be used only after an adverse effect(s) of this combination are determined.  相似文献   
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