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Two new species of Annulotrema Paperna & Thurston, 1969 were collected from the gills of the African tiger fish, Hydrocynus brevis, from the Gambia River basin in the Niokolo-Koba National Park, Senegal. Annulotrema besalis n. sp. is characterized by having a male copulatory organ (MCO) composed of an arcuate copulatory tube articulated to an eight-shaped accessory piece with terminal claw. The new species resembles Annulotrema pikei (Price, Peebles & Bamford, 1969) in having morphologically similar types of haptoral sclerites and MCO. As a result of the differential diagnosis made for A. besalis n. sp., new information on taxonomically important features of A. pikei is provided based on illustrations of the sclerotized parts of the holotype from Hydrocynus vittatus. The report of A. pikei on the gills of Hydrocynus forskahlii by Paperna in 1979 is shown to be erroneous. Annulotrema uncata n. sp. is similar to Annulotrema alestesimberi Paperna, 1973 in its possession of a coiled copulatory tube with about two and a half rings. Features distinguishing the new species include the sharply curved shaft of the ventral anchor, the base of the copulatory tube extending to a sock-like structure and a leech-shaped vagina. The necessity of emending the generic diagnosis of Annulotrema is briefly discussed.  相似文献   
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Although the effectiveness of nuclear hormone-receptor complexes is known to depend on coregulator partner proteins, relatively little is known about the roles of coregulators in uterine development and early stages of pregnancy and implantation. Because conventional genetic deletion of the coregulator, repressor of estrogen receptor activity (REA), was embryonic lethal, we here study REA conditional knockout mice generated by cre-loxP recombination, in which REA function was abrogated only in progesterone receptor-expressing tissues, to define the roles of REA in postembryonic stages and in a tissue-specific manner. We find that REA has gene dose-dependent activity impacting uterine development and fertility. Conditional homozygous mutant (REA(d/d)) mice developed to adulthood and showed normal ovarian function, but females were infertile with severely compromised uterine development and function characterized by cell cycle arrest, apoptosis, and altered adenogenesis (endometrial gland morphogenesis), resulting in failure of implantation and decidualization. By contrast, mice heterozygous for REA (REA(f/d)) had a very different phenotype, with estradiol treatment resulting in hyperstimulated, large uteri showing increased proliferation of luminal epithelial cells, and enhanced fluid imbibition associated with altered regulation of aquaporins. These REA(f/d) female mice showed a subfertility phenotype with reduced numbers and sizes of litters. These findings highlight that uterine development and regulation of estrogen receptor activities show a bimodal dependence on the gene dosage of REA. Optimal uterine development and functional activities require the normal gene dosage of REA, with partial or complete deletion resulting in hyperresponsiveness or underresponsiveness to hormone and subfertility or infertility, respectively.  相似文献   
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Adjunctive corticosteroid treatment to reduce excessive local inflammatory response in pneumonia is controversial. To study the effects of an early local adjunct dexamethasone treatment on the course of pneumonia and inflammatory/cytokine response, mice were intratracheally inoculated with live Porphyromonas gingivalis and treated with either clindamycin (C), dexamethasone (D), C+D combination, or were not treated (Pg). Six mice from each group were euthanized at 6, 24, 72, and 168 hours after inoculation. Levels of tumor necrosis factor (TNF)-α, soluble TNF-α receptors (sTNFR1 and sTNFR2), interleukin (IL)-1β, and IL-6 in the serum and lung-homogenate supernatant were determined. Lung samples were histopathologically assessed and all findings compared to those found in 24 sham-inoculated mice (phosphate-buffered saline [PBS]). Severe P. gingivalis-induced bronchopneumonia progressed from 24 hours, peaked at 72 hours, and resolved after 168 hours with changes in local and systemic cytokine levels. Clindamycin-treated mice developed only mild bronchopneumonia that resolved fast (72 hours) with an early (6-24 hours) normalization of local and systemic cytokine levels. Similar course of pneumonia and cytokine level changes were observed in mice treated with C+D, but later. Early (6-24 hours) local elevation of sTNFRs was observed in C and C+D groups of mice, whereas nontreated (Pg) mice had increased systemic sTNFRs. Severe bronchopneumonia with delayed resolution was observed in D-group mice, with an early local and systemic decrease in sTNFR1 and persistent elevation of local TNF-α. Clindamycin or a clindamycin-dexamethasone combination treatment significantly improves the course of P. gingivalis-aspiration pneumonia, but more so if clindamycin alone is used. A favorable course of pneumonia seems to be associated with an early elevation of sTNFRs and normalization of TNF-α.  相似文献   
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Background  

Pegylated interferon (PEG-IFN) and ribavirin is the most effective treatment for chronic hepatitis C virus (HCV) hepatitis, but the rate of sustained virological response (SVR) remains approximately 50%, and 15–20% of all treated patients have a virological relapse after completing the treatment. Studies on the SVR have failed to discriminate between non-responders and relapsers.  相似文献   
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Background

Moderate normobaric hyperoxia causes alveolar and vascular lung derangement in the newborn rat. Endogenous nitric oxide (NO), which promotes lung growth, is produced from the metabolism of l-arginine to l-citrulline in endothelial cells. We investigated whether administering l-citrulline by raising the serum levels of l-arginine and enhancing NO endogenous synthesis attenuates moderate hyperoxia-induced lung injury.

Methods

Newborn rats were exposed to FiO2?=?0.6 or room air for 14?days to induce lung derangement and then were administered l-citrulline or a vehicle (sham). Lung histopathology was studied with morphometric features. Lung tissues and bronchoalveolar lavage fluid (BALF) were collected for analysis. Lung vascular endothelial growth factor (VEGF), nitric oxide synthase (eNOS), and matrix metalloproteinase 2 (MMP2) gene and protein expressions were assessed.

Results

Serum l-arginine rose in the L-citr?+?hyperoxia group (p?=?0.05), as well as the Von Willebrand factor stained vessels count (p?=?0.0008). Lung VEGF immune staining, localized on endothelial cells, was weaker in the sections under hyperoxia than the l-citr?+?hyperoxia and room air groups. This pattern was comparable with the VEGF gene and protein expression profiles. Mean alveolar size increased in the untreated hyperoxia and sham-treated groups compared with the groups reared in room air or treated with l-citrulline under exposure to hyperoxia (p?=?0.0001). Lung VEGF and eNOS increased in the l-citrulline-treated rats, though this treatment did not change MMP2 gene expression but regulated the MMP2 active protein, which rose in BALF (p?=?0.003).

Conclusions

We conclude that administering l-citrulline proved effective in improving alveolar and vascular growth in a model of oxygen-induced pulmonary damage, suggesting better lung growth and matrix regulation than in untreated groups.  相似文献   
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