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Jeanne Altmann Dale Schoeller Stuart A. Altmann Philip Muruthi Robert M. Sapolsky 《American journal of primatology》1993,30(2):149-161
We used morphometric techniques and isotope-labeled water to investigate the influence of abundant, accessible food and resultant low activity levels on body size and fatness in free-living adolescent and adult baboons as compared to animals in the same population that experienced more typical, wild-feeding conditions. Females that had access to abundant food from a nearby garbage dump averaged 16.7 kg body mass, 50% more than their wild-feeding counterparts in adjacent home ranges. Little of the difference was due to lean mass: the animals with an accessible abundance of food averaged 23.2% body fat in contrast to 1.9% for the wild-feeding animals. Significant differences between feeding conditions were found for all measured skinfolds and for upper arm circumference but not for linear measurements. Differences between feeding conditions were less for males than for females, perhaps reflecting persistent effects of nutritional conditions during the first eight years of life before dispersal from the group of birth. The difference in fatness between feeding conditions was similar to the difference between humans with frank obesity and those that are considered lean, but in both cases the percentages of body fat in the baboons were considerably less than those observed in humans. In levels of fatness, the relatively sedentary animals resembled their counterparts in group-housed captive conditions. © 1993 Wiley-Liss, Inc. 相似文献
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Cardiolipin derivatives retaining the free hydroxyl on the polar head group were synthesized. With the use of a tetrahydropyranyl ether to protect this hydroxyl, fatty acyl substitutions were made at both of the 2-positions of cardiolipin (CL). The disubstituted derivatives were obtained in high yields. The stimulation of delipidated cytochrome c oxidase activity shows a hyperbolic dependence on the concentration of these CL derivatives. Both activation parameters, the apparent dissociation constant (Kd,app) and the maximum change in molecular activity (delta Actmax), depend on the chain length of the tails, with less dependence on the degree of saturation. Natural CL (92% C18:2, 8% C18:1) and CL disubstituted with oleic acid (47% C18:2, 52% C18:1) were equally effective at stimulating cytochrome c oxidase activity, with an apparent dissociation constant of approximately 1 microM when incubated in 0.3% Triton X-100 and assayed in lauryl maltoside. CL disubstituted with hexanoic acid, however, is a poorer activator, with an apparent dissociation constant of 6.8 microM and a delta Actmax that is 50% of that achieved with natural CL. Dilysocardiolipin, with complete removal of two of the fatty acid tails, shows negligible stimulation of cytochrome c oxidase activity. 相似文献
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Gary M. Stuhlmiller Timothy L. Darrow Dale M. Haupt H. F. Seigler 《Cancer immunology, immunotherapy : CII》1987,25(3):193-200
Summary Melanoma high molecular weight tumor-associated antigen (TAA), having a molecular weight of 250 kilodaltons (Kd), was purified from a crude cell membrane extract through a combination of lectin affinity, immunoadsorption, and high performance liquid molecular filtration chromatography. Compared to the starting extract, purified TAA was 600-fold higher in TAA activity per microgram of protein. Purified TAA was used to immunize a chimpanzee and the resulting antiTAA immune response was evaluated. Postimmune chimpanzee serum reacted in solid phase radioimmunoassay against purified TAA with a titer in excess of 100,000. In contrast, preimmune serum had a titer of <100 in the same assay. By immunoprecipitation analysis, we were able to demonstrate reactivity of the chimpanzee immune serum with a 250 Kd TAA in spent culture medium from melanoma cells metabolically labeled with 35S-methionine and with iodinated purified 250 Kd TAA. Reactivity of the chimpanzee antiserum for the 250 Kd TAA was confirmed in blocking and reciprocal immunodepletion studies using murine monoclonal antibody 9.2.27. These studies suggest that the 250 Kd TAA defined by murine monoclonal antibodies may prove to be immunogenic in man and that manipulation of the immune response to this TAA might be used to the clinical benefit of the patient.This work supported in part by Veterans Administration Hospital #821, by National Cancer Institute Grant #CA 32672 and by NIH Grant #RR 00165 from the Division of Research Resources to the Yerkes Regional Primate Research Center. The Yerkes Center is fully accredited by the American Association for Accreditation of Laboratory Animal Care 相似文献
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Epididymal sperm from the painted turtle (Chrysemys picta) possess a cytoplasmic droplet which is located eccentrically on the sperm midpiece. The droplet contains a large quantity of lipid droplets in addition to hollow vesicles and degenerate mitochondrial fragments. Lipid droplets are closely associated with mitochondrial membranes and may function in the formation or degradation of mitochondria. Cytoplasmic droplets become detached from the sperm midpiece in a coordinated manner shortly before the commencement of fall mating and are not observed on sperm recovered from the oviduct of females. © 1992 Wiley-Liss, Inc. 相似文献