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11.
12.
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   
13.
The goal of this study is to establish the nature of pentammineruthenium(III) binding to DNA in intact mouse liver nuclei. Also, we wish to determine whether the nucleosomal organization of mouse chromatin has a substantial effect on the relative Ru(III) binding levels of internucleosomal and nucleosomal core DNA. These questions are important because ammineruthenium compounds share chemical and biological properties with the cis-dichlorodiammineplatinum(II) or cisplatin chemotherapeutic agent. Therefore, they represent a potential class of new chemotherapeutic agents. We find that in intact nuclei the predominant DNA binding site for pentammineruthenium(II), followed by air oxidation to pentammineruthenium(III), is N-7 guanine, as is the case with cisplatin. Also, the Ru(III) distribution between internucleosomal and nucleosomal core DNA was found to be nearly identical as probed with three non-specific deoxyribonucleases.  相似文献   
14.
A number of acute phase proteins were determined by electroimmunoassay in media from CBA mouse hepatocytes cultured for 2 days with human recombinant IFN beta 2/IL-6, as well as with conditioned media from LPS-stimulated rat macrophages, and of murine L fibroblasts. It was found that human recombinant IL-6 caused three-fold increase in secretion of fibrinogen, while haptoglobin, complement C3 and transferrin were increased respectively, to 168 per cent, 151 per cent, and 145 per cent of the control. DEX(10(-7) M) in DMEM supplemented with 5 per cent FCS, enhanced the IL-6 effect on the three positive acute phase proteins. IL-6 elevated haptoglobin mRNA in mouse hepatocytes to a degree comparable with the concentration of the protein in the culture medium. The effect of conditioned media from murine fibroblasts and peritoneal rat macrophages was generally similar to that of recombinant IL-6. However, both natural preparations of the cytokines caused decrease in albumin and alpha-1-proteinase inhibitor secretion.  相似文献   
15.
A nonradiometric method has been developed for distinguishing between the sibling species Anopheles gambiae Giles and An. arabiensis Patton, two important Afrotropical vectors of malaria. DNA fragments of species diagnostic length are amplified by polymerase chain reaction (PCR) from a small amount of unknown DNA and three different PCR primers. All three PCR primers are based on ribosomal DNA (rDNA) sequences. A universal plus-strand primer (A0) is derived from a conserved region at the 3' end of the 28S rDNA coding region. Two species-specific minus-strand primers (Aa0.5 and Ag1.3) are derived from sequences in the intergenic spacers. The Ag1.3 sequence is approximately 1.3 kb downstream of A0; the Aa0.5 sequence is about 0.5 kb downstream of A0. When mosquito DNA is amplified in the presence of all three primers, a 1.3 kb fragment is produced if An. gambiae DNA is used as template, and a 0.5 kb fragment is produced if An. arabiensis DNA is used. Amplification of DNA from An.gambiae/An. arabiensis hybrids produces both the 1.3 kb and the 0.5 kb fragments. Neither diagnostic fragment is produced when DNA from other species in the An. gambiae complex is used as template.  相似文献   
16.
Summary This study identifies three discrete processes responsible for the rejection of tunic tissue transplanted between individuals of the solitary ascidian Styela plicata. The first stage of rejection is characterized by the destruction of blood vascular components within incompatible allografts. In the second phase, dense boundaries of extracellular material are deposited between grafts and the surrounding host tunic, effectively amputating the transplanted tissues. Finally, detached transplants undergo a gradual necrosis which results in the total degeneration of extracellular graft matrices. Of these three phases, the initial cellular depletion of allografts is responsible for the immunological specificity that is characteristic of histocompatibility in S. plicata. The subsequent amputation and necrosis of extracellular graft matrices are taken to be non-specific consequences of the initial cellular reactivity.  相似文献   
17.
Pre- and postoperative intradermal administration of OK-432 enhanced the SU-PS skin reaction in patients with gastric cancer, but failed to prevent a fall in the NK activity induced by the operation.The change in NK activity was not associated with a change in the proportion of Leu 7-positive cells, but was related to Leu 11a-positive cells. Intradermal injection of OK-432 increased the proportion of Leu 7-positive cells in the patients in whom they accounted for less than 20% of lymphocyte population. The case was the same with Leu 11a-positive cells.Intravenous injection of OK-432 tended to increase suppressor-inducer T cells (CD4+2HA+ cells), B cells and Leu 7-positive cells. Particularly, the proportions of OK-M1-positive cells and MHC class II antigen-positive cells increased in all patients. Immunotherapy with OK-432 given intravenously at a dose of 0.1 KE appeared to be safe because no side effects were essentially observed.  相似文献   
18.
Treatment of a mixture of Cys(R)(O) and Cys(R) with an acid was found to generate cystine in fairly good yields, when suitable R, R, and an acid were selected. An unsymmetrical cystine peptide was prepared by treatment of a mixture of Z(OMe)-Cys(R) (0)-Ala-NH2 (R=Acm or MBzl) and Z(OMe)-Cys(MBzl)-Gly-OBzl with TFA or 1 M TFMSA/TFA.3 Oxytocin was obtained in an excellent yield by TFA treatment of the protected peptide containing Cys(Acm)(0) and Cys(MBzl). Thus, formation of the disulfide bond was found feasible at the position of Cys(R) (0).The following abbreviations are used Boc t-butyloxycarbonyl - Z(OMe) p-methoxybenzyloxycarbonyl - MBzl p-methoxybenzyl - Acm acetamidomethyl - Bzl benzyl - Ad l-adamantyl - tBu t-butyl - TFA trifluoroacetic acid - TFMSA trifluoromethanesulfonic acid - TMSOTf trimethylsilyl trifluoromethane sulfonate  相似文献   
19.
Effect of exogenous fatty acids on zygote formation in Saccharomyces cerevisiae was studied. Arachidonic and oleic acids considerably stimulated zygote formation, but other fatty acids tested, linoleic, linolenic, stearic and palmitic acids, did not. Pretreatment experiments with arachidonic acid showed that the stimulation of zygote formation by the fatty acid required the presence of mating pheromone.Abbreviations YPD yeast-peptone-dextrose medium - A530 absorbance at 530 nm  相似文献   
20.
Many herbicides that inhibit photosynthesis in plants also inhibit photosynthesis in bacteria. We have isolated three mutants of the photosynthetic bacterium Rhodobacter sphaeroides that were selected for increased resistance to the herbicide terbutryne. All three mutants also showed increased resistance to the known electron transfer inhibitor o-phenanthroline. The primary structures of the mutants were determined by recombinant DNA techniques. All mutations were located on the gene coding for the L-subunit resulting in these changes Ile229 Met, Ser223 Pro and Tyr222 Gly. The mutations of Ser223 is analogous to the mutation of Ser264 in the D1 subunit of photosystem II in green plants, strengthening the functional analogy between D1 and the bacterial L-subunit. The changed amino acids of the mutant strains form part of the binding pocket for the secondary quinone, Q b . This is consistent with the idea that the herbicides are competitive inhibitors for the Q b binding site. The reaction centers of the mutants were characterized with respect to electron transfer rates, inhibition constants of terbutryne and o-phenanthroline, and binding constants of the quinone UQ0 and the inhibitors. By correlating these results with the three-dimensional structure obtained from x-ray analysis by Allen et al. (1987a, 1987b), the likely positions of o-phenanthroline and terbutryne were deduced. These correspond to the positions deduced by Michel et al. (1986a) for Rhodopseudomonas viridis.Abbreviations ATP adenosine 5-triphosphate - Bchl bacteriochlorophyll - Bphe bacteriopheophytin - bp basepair - cyt c2+ reduced form of cytochrome c - DEAE diethylami-noethyl - EDTA ethylenediamine tetraacetic acid - Fe2+ non-heme iron atom - LDAO lauryl dimethylamine oxide - Pipes piperazine-N,N-bis-2-ethane-sulfonic acid - PSII photosystem II - RC reaction center - SDS sodium dodecylsulfate - Tris tris(hydroxy-methyl)aminomethane - UQ0 2,3-dimethoxy-5-methyl benzoquinone - UQ10 ubiquinone 50  相似文献   
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