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71.
Tara S. Stoinski Bonnie M. Perdue Angela M. Legg 《American journal of primatology》2009,71(7):587-593
Previous research in gorillas suggests that females engage in post‐conception mating as a form of sexual competition designed to improve their own reproductive success. This study focused on sexual behaviors in a newly formed group of western lowland gorillas (Gorilla gorilla gorilla) housed at Zoo Atlanta. All females engaged in mating outside their conceptive periods, although there was individual variation in the frequency of the behavior. An analysis of the presence/absence of sexual behavior found females, regardless of reproductive condition, were more likely to engage in sexual behavior on days when other females were sexually active. On these “co‐occurrence” days, females were significantly more likely to solicit the silverback, but copulations did not differ from expectation. The results find further evidence for sexual competition among female gorillas and suggest that this may occur throughout their reproductive cycle rather than only during pregnancy. Am. J. Primatol. 71:587–593, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
72.
Diane M. Doran‐Sheehy David Fernández Carola Borries 《American journal of primatology》2009,71(12):1011-1020
Human females, unlike most mammals, are sexually active outside of fertile periods. This decoupling of sexual behavior from its conceptive function has had an enormous impact on human social relationships, and yet we know little about why there was selection for nonconceptive mating. Here we examine one form of nonconceptive mating, the mating that occurs during pregnancy or post‐conceptive (PC) mating, in wild western gorillas (Gorilla gorilla). Using a near complete mating record for five females during gestation, we show that pregnant females varied in the timing and frequency of mating, and used PC mating conditionally, synchronizing copulations to occur on days when other females mated, and refraining from mating for lengthy periods when no other females mated. As pregnant females mated exclusively with the same male before and after conception, and mated in response to group female (and not male) behavior, we conclude that western gorillas used PC mating as a form of female competition, and not to confuse paternity or to obtain immediate benefits from the male, as suggested earlier. The male initiated copulations preferentially with females of high rank, rather than distinguishing between pregnant and cycling females. Therefore, PC mating appears to be a strategy by which high‐ranking pregnant females attempt to minimize male interest in other females, while reinforcing their own status and potentially delaying conception in others. These findings indicate that female‐mating competition is more important than considered earlier, and may be a factor in the evolution of nonconceptive mating in humans. Am. J. Primatol. 71:1011–1020, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
73.
Post‐translational modifications of transthyretin affect the triiodonine‐binding potential 下载免费PDF全文
Andrea Henze Thomas Homann Mustafa Serteser Ozge Can Ozlem Sezgin Abdurrahman Coskun Ibrahim Unsal Florian J. Schweigert Aysel Ozpinar 《Journal of cellular and molecular medicine》2015,19(2):359-370
Transthyretin (TTR) is a visceral protein, which facilitates the transport of thyroid hormones in blood and cerebrospinal fluid. The homotetrameric structure of TTR enables the simultaneous binding of two thyroid hormones per molecule. Each TTR subunit provides a single cysteine residue (Cys10), which is frequently affected by oxidative post‐translational modifications. As Cys10 is part of the thyroid hormone‐binding channel within the TTR molecule, PTM of Cys10 may influence the binding of thyroid hormones. Therefore, we analysed the effects of Cys10 modification with sulphonic acid, cysteine, cysteinylglycine and glutathione on binding of triiodothyronine (T3) by molecular modelling. Furthermore, we determined the PTM pattern of TTR in serum of patients with thyroid disease by immunoprecipitation and mass spectrometry to evaluate this association in vivo. The in silico assays demonstrated that oxidative PTM of TTR resulted in substantial reorganization of the intramolecular interactions and also affected the binding of T3 in a chemotype‐ and site‐specific manner with S‐glutathionylation as the most potent modulator of T3 binding. These findings were supported by the in vivo results, which indicated thyroid function‐specific patterns of TTR with a substantial decrease in S‐sulphonated, S‐cysteinylglycinated and S‐glutathionylated TTR in hypothyroid patients. In conclusion, this study provides evidence that oxidative modifications of Cys10 seem to affect binding of T3 to TTR probably because of the introduction of a sterical hindrance and induction of conformational changes. As oxidative modifications can be dynamically regulated, this may represent a sensitive mechanism to adjust thyroid hormone availability. 相似文献
74.
Ge Liu Yangfei Xiang Chaowan Guo Ying Pei Yifei Wang Kaio Kitazato 《Biochemical and biophysical research communications》2014
Influenza A virus (IAV) assembly and budding on host cell surface plasma membrane requires actin cytoskeleton reorganization. The underlying molecular mechanism involving actin reorganization remains unclarified. In this study, we found that the natural antiviral compound petagalloyl glucose (PGG) inhibits F-actin reorganization in the host cell membrane during the late stage of IAV infection, which are associated with the suppression of total cofilin-1 level and its phosphorylation. Knock-down of cofilin-1 reduces viral yields. These findings provide the first evidence that cofilin-1 plays an important role in regulating actin reorganization during IAV assembly and budding. 相似文献
75.
Jinxi Li Kevin Shefcheck John Callahan Catherine Fenselau 《Protein science : a publication of the Protein Society》2010,19(1):174-182
The Ara h 2 proteins are major determinants of peanut allergens. These proteins have not been fully studied at the molecular level. It has been previously proposed that there are two isoforms of Ara h 2, based on primary structures that were deduced from two reported cDNA sequences. In this report, four isoforms have been purified and characterized individually. Mass spectrometric methods have been used to determine the protein sequences and to define post‐translational modifications for all four isoforms. Two pairs of isoforms have been identified, corresponding to a long‐chain form and a form that is shorter by 12 amino acids. Each pair is further differentiated by the presence or absence of a two amino acid sequence at the carboxyl terminus of the protein. Modifications that were characterized include site‐specific hydroxylation of proline residues, but no glycosylation was found, in contrast to previous reports. 相似文献
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78.
Hagai Tavori Yan Ru Su Patricia G. Yancey Ilaria Giunzioni Ashley J. Wilhelm John L. Blakemore Manal Zabalawi MacRae F. Linton Mary G. Sorci-Thomas Sergio Fazio 《Journal of lipid research》2015,56(3):635-643
Tissue cholesterol accumulation, macrophage infiltration, and inflammation are features of atherosclerosis and some forms of dermatitis. HDL and its main protein, apoAI, are acceptors of excess cholesterol from macrophages; this process inhibits tissue inflammation. Recent epidemiologic and clinical trial evidence questions the role of HDL and its manipulation in cardiovascular disease. We investigated the effect of ectopic macrophage apoAI expression on atherosclerosis and dermatitis induced by the combination of hypercholesterolemia and absence of HDL in mice. Hematopoietic progenitor cells were transduced to express human apoAI and transplanted into lethally irradiated LDL receptor−/−/apoAI−/− mice, which were then placed on a high-fat diet for 16 weeks. Macrophage apoAI expression reduced aortic CD4+ T-cell levels (−39.8%), lesion size (−25%), and necrotic core area (−31.6%), without affecting serum HDL or aortic macrophage levels. Macrophage apoAI reduced skin cholesterol by 39.8%, restored skin morphology, and reduced skin CD4+ T-cell levels. Macrophage apoAI also reduced CD4+ T-cell levels (−32.9%) in skin-draining lymph nodes but had no effect on other T cells, B cells, dendritic cells, or macrophages compared with control transplanted mice. Thus, macrophage apoAI expression protects against atherosclerosis and dermatitis by reducing cholesterol accumulation and regulating CD4+ T-cell levels, without affecting serum HDL or tissue macrophage levels. 相似文献
79.
Anaerobic pretreated paper process water was characterized interms of readily biodegradable, slowly biodegradable, very slowly biodegradable and inert wastewaterfractions under mesophilic and thermophilic conditions. The anaerobic pretreated paper process water containeda relatively high amount of slowly biodegradable components and few easily biodegradable componentsas indicated by the ratio of short term BOD over the BOD5. Wastewater readily biodegradable COD, determinedas short term BOD, was almost similar when measured under both temperature conditions. Fractions ofslowly biodegradable COD and inert COD of the same wastewater were found to depend on the type of biomassinvolved in the test. Thermophilic aerobic biomass was not able to degrade the wastewater to the sameextent as the mesophilic biomass resulting in higher apparent inert COD levels. Furthermore, wastewater colloidalCOD did not flocculate under thermophilic conditions and was thus not removed from the liquid phase. 相似文献
80.
Xavier Calvet Sergio Lario María José Ramírez‐Lázaro Antònia Montserrat Mariela Quesada Lynsey Reeves Helen Masters David Suárez‐Lamas Marta Gallach Mireia Miquel Eva Martínez‐Bauer Isabel Sanfeliu Ferran Segura 《Helicobacter》2010,15(3):201-205
Background: Studies comparing new monoclonal fecal tests for evaluating cure of Helicobacter pylori infection after treatment are scarce. The objective was to compare the diagnostic accuracy of three monoclonal stool tests: two rapid in‐office tools –RAPID Hp StAR and ImmunoCard STAT! HpSA – and an EIA test – Amplified IDEIA Hp StAR. Materials and methods: Diagnostic reliability of the three tests was evaluated in 88 patients at least 8 weeks after H. pylori treatment. Readings of immunochromatographic tests were performed by two different observers. Sensitivity, specificity, positive and negative predictive values and 95% confidence intervals were calculated. Results: All tests presented similar performance for post‐eradication testing. Sensitivity for detecting persistent infection was 100% for both Amplified IDEIA and RAPID Hp StAR and 90% for ImmunoCard STAT! HpSA. Respective specificities were 94.9%, 92.3–93.6% and 94.9%. Negative predictive values were very high (100%, 100% and 98.7% respectively). But positive predictive values were lower, ranging from 62.5 to 71.4%. Conclusion: All monoclonal fecal tests in this series presented similar performance in the post‐treatment setting. A negative test after treatment adequately predicted cure of the infection. However, nearly a third of tests were false positive, showing a poor predictive yield for persistent infection. 相似文献