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51.
52.
Linkage mapping of the MC3R gene to porcine chromosome 17 总被引:1,自引:0,他引:1
53.
To evaluate whether observed cycles in proceptive behavior in aging lowland gorilla females (age 40+) at Brookfield Zoo were driven by ovarian activity, we compared monthly behavioral data to estradiol and progestogen cycles based on fecal hormone assessments. Progestogen peaks showed regularity and close coincidence with monthly sexual behaviors. Estradiol was more variable. Progestogen peaks varied between 22+/-5 days for the control female (29 years old), to 24+/-2.5 and 29+/-8 for the two aged subjects. In the first aged female, which was housed with other females and a silverback, the high degree of cyclicity in sexual behavior, regularity of progestogen cycles, and close concordance between hormonal cycling and sexual behavior strongly compared to patterns found (in this and other studies) in gorilla females <35 years old. Cyclical progestogen peaks were longer and more variable in the second aged female-perhaps because she lacked the social mediation of other females or a male. For husbandry reasons she is not housed with the gorilla group, behavioral data were not collected from her. The value of our longitudinal study is in obtaining reproductive profiles of primate females that are approaching maximum lifespan. This pilot study is part of a larger research project on reproductive senescence that will include other captive females >35 years old, a population that is rapidly increasing in North American zoos as gorillas continue to age. 相似文献
54.
Somjen D Kohen F Gayer B Knoll E Limor R Baz M Sharon O Posner GH Stern N 《The Journal of steroid biochemistry and molecular biology》2004,(1-5):397-399
In cultured human vascular smooth muscle cells (VSMC), estradiol-17beta (E2) induced a biphasic effect on DNA synthesis, i.e., stimulation at low concentrations and inhibition at high concentrations. Additionally, E2 increased the specific activity of creatine kinase (CK) in these cells. Observations that novel protein-bound membrane impermeant estrogenic complexes could elicit inhibition of DNA synthesis, suggested interaction via membranal binding sites. Nevertheless other effects, such as increasing CK activity were only seen with native E2 but not with E2-BSA, thus indicating that the classical nuclear receptor pathway was involved. In the present report, we confirm that human VSMC express both ERalpha and ERbeta. Further, pretreatment of cultured VSMC with the Vitamin D non-calcemic analog JK 1624 F2-2 (JKF) increased ERalpha mRNA (100-200%) but decreased ERbeta mRNA (30-40%) expression as measured by real time PCR. ERalpha protein expression assessed by Western blot analysis increased (25-50%) in parallel, whereas ERbeta protein expression declines (25-55%). Using ovalbumin bound to E2 (Ov-E2) linked to Eu (Eu-Ov-E2), to assess specific membrane binding sites, we observed that membranal binding was down regulated by JKF by 70-80%. In contrast, total cell binding of 3[H] E2, that nearly entirely represents intracellular E2 binding, was increased by 60-100% by the same Vitamin D analog. The results provide evidence that the effects of JKF on ERalpha/ERbeta as well as on membranal versus nuclear binding of estrogen are divergent and show differential modulation. 相似文献
55.
Until now, the predominant use cases of industrial robots have been routine handling tasks in the automotive industry. In biotechnology and tissue engineering, in contrast, only very few tasks have been automated with robots. New developments in robot platform and robot sensor technology, however, make it possible to automate plants that largely depend on human interaction with the production process, e.g., for material and cell culture fluid handling, transportation, operation of equipment, and maintenance. In this paper we present a robot system that lends itself to automating routine tasks in biotechnology but also has the potential to automate other production facilities that are similar in process structure. After motivating the design goals, we describe the system and its operation, illustrate sample runs, and give an assessment of the advantages. We conclude this paper by giving an outlook on possible further developments. 相似文献
56.
The MHC class I-like IgG receptor controls perinatal IgG transport,IgG homeostasis,and fate of IgG-Fc-coupled drugs 总被引:1,自引:0,他引:1
Roopenian DC Christianson GJ Sproule TJ Brown AC Akilesh S Jung N Petkova S Avanessian L Choi EY Shaffer DJ Eden PA Anderson CL 《Journal of immunology (Baltimore, Md. : 1950)》2003,170(7):3528-3533
Abs of the IgG isotype are efficiently transported from mother to neonate and have an extended serum t(1/2) compared with Abs of other isotypes. Circumstantial evidence suggests that the MHC class I-related protein, the neonatal FcR (FcRn), is the FcR responsible for both in vivo functions. To understand the phenotypes imposed by FcRn, we produced and analyzed mice with a defective FcRn gene. The results provide direct evidence that perinatal IgG transport and protection of IgG from catabolism are mediated by FcRn, and that the latter function is key to IgG homeostasis, essential for generating a potent IgG response to foreign Ags, and the basis of enhanced efficacy of Fc-IgG-based therapeutics. FcRn is therefore a promising therapeutic target for enhancing protective humoral immunity, treating autoimmune disease, and improving drug efficacy. 相似文献
57.
Shimizu M Kobayashi K Morii H Mitsui K Knoll W Nagamune T 《Biochemical and biophysical research communications》2003,310(2):606-611
In order to analyze the secondary structures of protein molecules adsorbed on gold surfaces, circular dichroism (CD) spectra were measured and the secondary structure contents of protein ultra-thin films were estimated quantitatively. A disulfide group was introduced to cytochrome b(562) (cyt.b562), which is a water-soluble b-type heme protein. The cyt.b562 molecules self-assembled to form an ultra-thin protein film both on a gold substrate modified with 2,2(')-dithiodiacetic acid and on a bare gold surface. CD measurements were carried out both in solution and in air, and these results were compared. The protein denaturation was partially prevented, not only in solution but also in air, by both the modification of the substrate and the introduction of the anchor group to the protein molecule. The secondary structure contents of ultra-thin protein films on flat gold surfaces were observed for the first time both in solution and in air by CD spectra. 相似文献
58.
59.
Yoneda F Moto T Sakae M Ohde H Knoll B Miklya I Knoll J 《Bioorganic & medicinal chemistry》2001,9(5):1197-1212
The catecholaminergic and serotoninergic neurons in the brain change their performance according to the physiological need via a catecholaminergic/serotoninergic activity enhancer (CAE/SAE) mechanism. Phenylethylamine (PEA), tyramine and tryptamine are the presently known endogenous CAE/SAE substances which enhance the impulse propagation mediated release of catecholamines and serotonin in the brain. A PEA derivative, (-)deprenyl (selegiline), known as a selective inhibitor of MAO-B, is for the time being the only CAE/SAE substance in clinical use. Aiming to develop a selective CAE/SAE substance much more potent than (-)deprenyl, a series of new 1-aryl-2-alkylaminoalkanes, structurally unrelated to PEA and the amphetamines, was designed and prepared. Among them, (-)1-(benzofuran-2-yl)-2-propylaminopentane ((-)BPAP) was selected as a promising candidate substance for further studies. (-)BPAP significantly enhanced in rats the impulse propagation mediated release of catecholamines and serotonin in the brain 30min after acute injection of 0.36nmol/kg sc. In the shuttle box, (-)BPAP was in rats about 130 times more potent than (-)deprenyl in antagonizing tetrabenazine induced inhibition of performance. (+/-)BPAP protected cultured hippocampal neurons from the neurotoxic effect of beta-amyloid in 10(-14)-10(-15)M concentration. 相似文献
60.
Oka T Yasusa T Ando T Watanabe M Yoneda F Ishida T Knoll J 《Bioorganic & medicinal chemistry》2001,9(5):1213-1219
Enantioselective synthesis and absolute configuration of (-)-1-(benzofuran-2-yl)-2-propylaminopentane ((-)-BPAP), which is a highly potent and selective catecholaminergic activity enhancer (CAE) substance, are described. The synthetic approach consists of the coupling reaction of benzofuran with (R)-N-tosyl-2-propylazirizine or (R)-N-methoxy-N-methylnorvaliamide, followed by appropriate modifications of the resulting coupling products. As the results, (-)-BPAP turned out to have the R configuration, which was finally confirmed by X-ray crystallographic analysis. 相似文献