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1.
Hostile intercommunity relations, including attacking and killing extra-community infants of both sexes have occurred at most
wild chimpanzee sites. We describe three recent cases of intercommunity attacks on infants committed by members of the Ngogo
chimpanzee community in Kibale National Park, Uganda. Two of the attacks resulted in confirmed infanticides while a third
attack probably resulted in the infant's death. In common with previous accounts of chimpanzee infanticides, the attacks described
here occurred during boundary patrols outside the Ngogo community's usual range, adult and adolescent males were the main
participants, one infant was cannibalized after being killed, and the victims’ mothers did not accompany the attacking party
back to the Ngogo range. However, the patrol parties during each infanticide were larger than before and included females
from the Ngogo community. Our observations indirectly support both the range expansion and imbalance of power hypotheses,
which address why and under which conditions chimpanzee intercommunity encounters lead to aggression. These cases of intercommunity
infanticide add to the growing database of the phenomenon in wild chimpanzees. 相似文献
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Julie K. De Zutter Kara B. Levine Di Deng Anthony Carruthers 《The Journal of biological chemistry》2013,288(28):20734-20744
The human blood-brain barrier glucose transport protein (GLUT1) forms homodimers and homotetramers in detergent micelles and in cell membranes, where the GLUT1 oligomeric state determines GLUT1 transport behavior. GLUT1 and the neuronal glucose transporter GLUT3 do not form heterocomplexes in human embryonic kidney 293 (HEK293) cells as judged by co-immunoprecipitation assays. Using homology-scanning mutagenesis in which GLUT1 domains are substituted with equivalent GLUT3 domains and vice versa, we show that GLUT1 transmembrane helix 9 (TM9) is necessary for optimal association of GLUT1-GLUT3 chimeras with parental GLUT1 in HEK cells. GLUT1 TMs 2, 5, 8, and 11 also contribute to a less abundant heterocomplex. Cell surface GLUT1 and GLUT3 containing GLUT1 TM9 are 4-fold more catalytically active than GLUT3 and GLUT1 containing GLUT3 TM9. GLUT1 and GLUT3 display allosteric transport behavior. Size exclusion chromatography of detergent solubilized, purified GLUT1 resolves GLUT1/lipid/detergent micelles as 6- and 10-nm Stokes radius particles, which correspond to GLUT1 dimers and tetramers, respectively. Studies with GLUTs expressed in and solubilized from HEK cells show that HEK cell GLUT1 resolves as 6- and 10-nm Stokes radius particles, whereas GLUT3 resolves as a 6-nm particle. Substitution of GLUT3 TM9 with GLUT1 TM9 causes chimeric GLUT3 to resolve as 6- and 10-nm Stokes radius particles. Substitution of GLUT1 TM9 with GLUT3 TM9 causes chimeric GLUT1 to resolve as a mixture of 6- and 4-nm particles. We discuss these findings in the context of determinants of GLUT oligomeric structure and transport function. 相似文献
4.
Treatment of cut-throat trout broodfish Salmo clarki (Richardson) with Sulphamerazine at 220 mg/kg (10 g/100 1b) of fish/day for 14 days resulted in severe kidney histopathology and increased mortality among males. Experimental data presented showed that cut-throat trout broodfish were extremely sensitive to Sulphamerazine toxicity. Hydropic degeneration of renal tubule epithelium and haemorrhage into tubule lumens were observed in kidneys of both male and female trout, but was more severe in the former. Death, which occurred only in males, was correlated with spawning stress and impaired renal function. 相似文献
5.
Susan Morrison Grace John-Stewart John J. Egessa Sezi Mubezi Sylvia Kusemererwa Dennis K. Bii Nulu Bulya Francis Mugume James D. Campbell Jonathan Wangisi Elizabeth A. Bukusi Connie Celum Jared M. Baeten Partners PrEP Study Team 《PloS one》2015,10(10)
During an HIV-1 prevention clinical trial in East Africa, we observed 16 cases of primary HIV-1 infection in women coincident with pregnancy or breastfeeding. Nine of eleven pregnant women initiated rapid combination antiretroviral therapy (ART), despite having CD4 counts exceeding national criteria for ART initiation; breastfeeding women initiated ART or replacement feeding. Rapid ART initiation during primary HIV-1 infection during pregnancy and breastfeeding is feasible in this setting. 相似文献
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Structure-function relationships of the adenovirus DNA-binding protein. 总被引:22,自引:0,他引:22
8.
Glen R. Needham Rosemarie Rosell Lewis Greenwald 《Experimental & applied acarology》1990,10(2):83-104
We describe the ultrastructure of type-I salivary-gland acini in two argasid and two ixodid species. The basic cell types in the agranular or type-I acini, and their associations, are very similar in argasids and ixodids; therefore, we propose an anatomical nomenclature for cells in the type-I acinus based on the adult ixodidsAmblyomma americanum andDermacentor variabilis, and the argasid adultArgas (Persicargas) arboreus and on nymphalOrnithodoros moubata. Four cell types were present in all specimens: one central lamellate cell, a variable number of peripheral lamellate cells, a variable number of peritubular cells depending on the species, and one circumlumenal cell. The lamellate cells had infolded basal plasma membranes that presented an amplified surface area to the hemolymph. These cells most likely secreted the fluid involved in water vapor uptake by ticks. ForAmblyomma americanum females, abundant K+-dependent, ouabain-sensitive Na+, K+-ATPase complexes were located on the infolded basal plasma membranes of the lamellate cells. Apical membranes of the lamellate cells, and plasma membranes of other cell types in the acinus had little or no evidence of Na+, K+-ATPase activity. Only the central lamellate cell extended from the hemolymph of the acinus to its lumen; peripheral cells did not contact the lumen. Except when the ticks were rehydrating, lipid inclusions were common features in the lamellate cells of the ixodids. Lipid inclusions were not seen in argasid type I acini; however, glycogen deposits were common. To determine if acinar cells respond to the changing hydration state of the tick, unfed femaleA. americanum were subjected to dehydration/rehydrating conditions. During rehydration, mitochondria in the lamellate cells changed from a matrix of medium electron-density and intermembrane space (orthodox configuration) to a matrix of greater density and larger intermembrane space (condensed configuration). The orthodox configuration was consistently observed in control and dehydrating ticks. The condensed configuration was the norm for mitochondria in lamellate cells of rehydrating ticks. Lipid inclusions were depleted in the rehydrating ticks compared to control or dehydrating ticks. Acini appeared to be reverting to the control or desiccated state when ticks were returned to low humidity, suggesting that these changes were cyclical. Nymphs ofO. moubata subjected to the same dehydration/rehydrating conditions showed no obvious ultrastructural changes. 相似文献
9.
Harjot K. Saini-Chohan Michael G. Holmes Adam J. Chicco William A. Taylor Russell L. Moore Sylvia A. McCune Diane L. Hickson-Bick Grant M. Hatch Genevieve C. Sparagna 《Journal of lipid research》2009,50(8):1600-1608
Cardiolipin (CL) is responsible for modulation of activities of various enzymes involved in oxidative phosphorylation. Although energy production decreases in heart failure (HF), regulation of cardiolipin during HF development is unknown. Enzymes involved in cardiac cardiolipin synthesis and remodeling were studied in spontaneously hypertensive HF (SHHF) rats, explanted hearts from human HF patients, and nonfailing Sprague Dawley (SD) rats. The biosynthetic enzymes cytidinediphosphatediacylglycerol synthetase (CDS), phosphatidylglycerolphosphate synthase (PGPS) and cardiolipin synthase (CLS) were investigated. Mitochondrial CDS activity and CDS-1 mRNA increased in HF whereas CDS-2 mRNA in SHHF and humans, not in SD rats, decreased. PGPS activity, but not mRNA, increased in SHHF. CLS activity and mRNA decreased in SHHF, but mRNA was not significantly altered in humans. Cardiolipin remodeling enzymes, monolysocardiolipin acyltransferase (MLCL AT) and tafazzin, showed variable changes during HF. MLCL AT activity increased in SHHF. Tafazzin mRNA decreased in SHHF and human HF, but not in SD rats. The gene expression of acyl-CoA: lysocardiolipin acyltransferase-1, an endoplasmic reticulum MLCL AT, remained unaltered in SHHF rats. The results provide mechanisms whereby both cardiolipin biosynthesis and remodeling are altered during HF. Increases in CDS-1, PGPS, and MLCL AT suggest compensatory mechanisms during the development of HF. Human and SD data imply that similar trends may occur in human HF, but not during nonpathological aging, consistent with previous cardiolipin studies. 相似文献
10.