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A E Macias S W Wong D W Sadowsky C M Luetjens M K Axthelm M G Gravett G J Haluska M J Novy 《American journal of primatology》2001,55(3):159-170
Leukocytes can be found in substantial numbers within the intrauterine tissues and amniotic fluid of women, and play a central role in the pathophysiology of infection-related preterm labor by their production of proinflammatory mediators. It remains unclear whether these leukocytes represent a fetal immune response, a maternal response, or a combination of the two. The objective of this study was to develop a test in the rhesus monkey (Macaca mulatta) suitable for determining the percentage of male fetal cells present in a population of leukocytes recovered from blood or amniotic fluid. We found inadequate specificity for rhesus monkey cells using commercial human Y-chromosome paint kits (fluorescence in situ hybridization (FISH)). Human-specific primers for the repetitive Y chromosome DYZ-1 locus employed in the polymerase chain reaction (PCR) produced an unacceptable percentage of false positives. However, we successfully developed a PCR-based test using rhesus-specific primers for the zinc finger Y (ZFY) locus. Densitometry of PCR products from known ratios of male and female adult peripheral leukocytes generated a linear standard curve which provided quantitative results and required only 400 cells per sample. The rhesus beta globin (RBG) gene served as an internal control. The PCR test correctly discriminated the sex of peripheral leukocytes in 20 adult males, 20 adult females, two male fetuses, and one female fetus. Serial samples of amniotic fluid from four chronically catheterized rhesus monkeys bearing male fetuses were used to confirm the utility of this assay for quantifying fetal cells in amniotic fluid. In conclusion, we have developed a PCR test which is suitable for distinguishing male from female cells in adult and fetal blood and in amniotic fluid, which lends itself to a variety of diagnostic and biologic applications in the rhesus monkey and potentially in other nonhuman primates. 相似文献
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借助于5'和3'末端删切后重建的IL-2R a链基因调控区次级克隆,在体外合成有放射性同位素参入的反意义RNA探针与总RNA进行液相杂交,结果表明TPA或PHA分别活化的T细胞在IL-2R a链表达过程中都在不同程度上有选择地利用了调控区内分别为-58(5')和+1(3')位两个转录起始点中3'转录起始点。热休克使PHA活化细胞更明显地利用+1位点。PHA诱导Jurkat细胞表达IL-2RamRNA斑点杂交证实,Jurkat细胞在活化16小时表达IL-2Ra基本达到高峰,至24小时已明显下降。根据这一规律提取PHA诱导活化15小时的Jurkat细胞S100和NE,进行有关结合蛋白的研究,初步结果显示磷酸纤维素柱的KCI洗脱组分中存在着DNA结合蛋白,有关结合蛋白性质的研究正在进行中。 相似文献
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Molecular dynamics simulations were carried out on an insulin crosslinked between the N-terminal A chain and the C-terminal B chain to form a so-called mini-proinsulin: N
-A1-N
-B29-diaminosuberoyl insulin (DASI). To investigate the influence of crosslinking on the dynamics of the insulin moiety, the bridge was removed from a transient DASI structure and simulation was carried on independently with the then unlinked (ULKI) as well as with the crosslinked species. The effects of crystal packing and quaternary interactions were checked by simulating both types of monomers and dimers known from the hexamer structure. All simulations were compared to previous ones of native insulin. DASI shows general similarity to the native simulations in most parts of the structure. Deviations are visible in the segments to which the bridge is directly connected, i.e. their flexibility is reduced. Upon removal of the bridge the ULKI simulations reapproach those of native insulin. The influence of the bridge spreads over the whole molecule, but all of its main structural features remain intact. The simulations suggest that the displacement of the C-terminal B chain of native insulin, considered important for receptor interaction, is prevented by the bridge, which also partially shields some binding residues. This is in accordance with the poor biological potency of A1-B29-crosslinked insulins.Abbreviations DASI-insulin(DASI)
bovineN
-A1-N
-B29-di-aminosuberoyl insulin
- ULK-insulin (ULKI)
Native beef insulin with the bridge of DASI removed 相似文献
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Age-Dependent Impairment of Mitochondrial Function in Primate Brain 总被引:11,自引:2,他引:9
Allen C. Bowling Elizabeth M. Mutisya Lary C. Walker† Donald L. Price†‡§ Linda C. Cork† M. Hint Beal 《Journal of neurochemistry》1993,60(5):1964-1967
Abstract: It has been hypothesized that some of the functional impairments associated with aging are the result of increasing oxidative damage to mitochondrial DNA that produces defects in oxidative phosphorylation. To test this hypothesis, we examined the enzymes that catalyze oxidative phosphorylation in crude mitochondrial preparations from frontoparietal cortex of 20 rhesus monkeys (5-34 years old). Samples were assayed for complex I, complex II-III, complex IV, complex V, and citrate synthase activities. When enzyme activities were corrected for citrate synthase activities (to account for variable degrees of mitochondrial enrichment), linear regression analysis demonstrated a significant negative correlation of the activities of complex I (p < 0.002) and complex IV (p < 0.03) with age but no significant change in complex II-III or complex V activities. Relative to animals 6.9 ± 0.9 years old (n = 7), the citrate synthase-corrected activity of complex I was reduced by 17% in animals 22.5 ± 0.9 years old (n = 6) (p < 0.05) and by 22% in animals 30.7 ± 0.9 years old (n = 7) (p < 0.01). Similar age-related reductions in the activities of complexes I and IV were obtained when enzyme activities were corrected for complex II-III activity. These findings show an age-associated progressive impairment of mitochondrial complex I and complex IV activities in cerebral cortices of primates. 相似文献