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231.
Barbara Lubec Zhuang Ya-hua Sainio Pertti Tuohimaa Pentti Erwin Kitzmüller Gert Lubec 《Life sciences》1997,60(26):618-2381
L-arginine and taurine are still in the center of physiological and pharmacological research. Although the fate of nitrogen of both compounds and of the 35S-taurine is well-documented, the fate of the carbon skeleton has not been elucidated yet. We studied the organ distribution of 14C arginine and 14C taurine over time in the mouse using whole body autoradiography with densitometric image analysis. We describe different organ distribution patterns. Kidney, heart, lung, the Harderian gland, the central nervous system, intestine and testis showed a comparable pattern of arginine disappearance in contrast to rapid disappearance in the salivary gland and the accumulation pattern in bone and spleen. Data on 14C taurine of liver, kidneys, lung, testis and Harderian gland resembled the arginine pattern; Accumulation of taurine carbon was found in salivary gland, bone, intestine, heart and brain. Our studies challenge and demand further related studies to obtaining more information on the fate of the carbon skeleton of these amino acids. 相似文献
232.
Zheng, Lu P., Rui Sheng Du, and Barbara E. Goodman.Effects of acute hyperoxic exposure on solute fluxes across the blood-gas barrier in rat lungs. J. Appl.Physiol. 82(1): 240-247, 1997.We investigatedeffects of acute hyperoxia on solute transport from air space tovascular space in isolated rat lungs. Air spaces were filled withKrebs-Ringer bicarbonate solution containing fluoresceinisothiocyanate-labeled dextran (FD-20; mol wt 20,000) and either22Na+and [14C]sucrose, orD-[14C]glucoseandL-[3H]glucose.Apparent permeability-surface area products for tracers over time (upto 120 min) were calculated for isolated perfused lungs from controlrats (room air) and rats exposed to >95%O2 for 48 or 60 h immediatelypostexposure. After O2 exposures,mean fluxes for[14C]sucrose and FD-20were significantly higher than in room-air control lungs. However,amiloride-sensitive Na+ and activeD-glucose fluxes were unchangedafter hyperoxic exposure. Therefore, it is unlikely that decreases innet solute transport in this lung-injury model contributed to pulmonaryedema resulting from O2 toxicity.Increased net solute transport shown to help resolve pulmonary edemaafter acute hyperoxic exposure must therefore begin during the recoveryperiod. In summary, our data show increases in passive solute fluxesbut no changes in active solute fluxes immediately after acutehyperoxic lung injury. 相似文献
233.
Paweł Kafarski Barbara Lejczak Roman Tyka Lucyna Koba Elżbieta Pliszczak Piotr Wieczorek 《Journal of Plant Growth Regulation》1995,14(4):199-203
A series of phosphonic, phosphinic, and phosphonous acid analogues of phenylglycine and phenylalanine was synthesized and tested as herbicides against Lepidium sativum and Cucumis sativus. Aminobenzylphosphonic acids exhibited notable herbicidal activity and thus represent a group of the most active herbicides found among aminophosphonic acids. 相似文献
234.
A point mutation in the tyrosine hydroxylase gene associated with Segawa's syndrome 总被引:14,自引:0,他引:14
We have examined the molecular basis of Segawa's syndrome in six families with seven affected children. In one family two siblings with this disease carried a point mutation in exon 11 of the tyrosine hydroxylase gene, resulting in an amino acid exchange of Gln381 to Lys381. These results suggest that a change in tyrosine hydroxylase causes this form of Segawa's syndrome. 相似文献
235.
A de novo satellited short arm of the Y chromosome possibly resulting from an unstable translocation
A satellited long arm of the Y chromosome (Yqs) is considered a normal variation, whereas the presence of a satellite on the short arm of the Y (Yps) has never been described in the literature. A Yps chromosome could be clinically significant if the translocation resulting in Yps has relocated the testis-determining gene, SRY, to another chromosome. A carrier of such a translocation would therefore be at increased risk for having XX male and XY female offspring. Here we describe the first reported case of de novo Yps present in a phenotypically normal male. This Yps chromosome was positive for C-banding and nucleolus organizer region (NOR) staining and showed a hybridization signal for the -satellite sequence. Fluorescence in situ hybridization (FISH) analysis indicated that SRY was retained on the Yps and the translocation breakpoint on Yps was distal to the pseudoautosomal region. At prenatal diagnosis, a normal appearing Y chromosome was found in his son, and thus the satellite on Yps was lost during meiotic Xp-Yp pairing. This Yps chromosome was likely the product of an unstable translocation. 相似文献
236.
237.
Gracjana Klein Robert Walczak Ewa Krasnowska Adam Blaszczak Barbara Lipiska 《Molecular microbiology》1995,16(4):801-811
We have investigated heat-shock response in a marine bacterium Vibrio harveyi. We have found that 39 C was the highest tempature at which V. harveyi was able to grow steadily. A shift from 30° C to 39° C caused increased synthesis of at least 10 proteins, as judged by SDS-PAGE, with molecular masses of 90, 70, 58, 41, 31, 27, 22, 15, 14.5 and 14kDa. The 70, 58, 41 and 14.5 kDa proteins were immunologically homologous to DnaK, GroEL, DnaJ and GroES heat-shock proteins of Escherichia coli, respectively. V. harveyi GroES protein had a lower molecular mass (14.5 kDa) than E. coli GroES, migrating in SDS-PAGE as 15 kDa protein. We showed that a protein of ~43 kDa, immunologically reactive with antiserum against E. coli sigma 32 subunit (σ32) of RNA polymerase, was induced by heat-shock and co-purified with V. harveyi RNA polymerase. These results suggest that the 43 kDa protein is a heat-shock sigma protein of V. harveyi. Preparation containing the V. harveyi sigma 32 homologue, supplemented with core RNA polymerase of E. coli, was able to transcribe heat-shock promoters of E. coli in vitro. 相似文献
238.
Richard L. Schading Raymond I. Carruthers Barbara A. Mullin-Schading 《Biocontrol Science and Technology》1995,5(2):201-208
The viability of conidia from two species of deuteromycetes fungi pathogenic to insects was determined using two fluorochrome stains, fluorescein diacetate (FDA) and propidium iodide (PI). These stains were used either alone or in combination, and results were compared with standard conidial germination tests. FDA fluoresces bright green in viable conidia and PI fluoresces red in non-viable conidia, when viewed using specific fluorescence microscopic techniques. Conidia from two isolates of Paecilomyces fumosoroseus (Wize) Brown and Smith and two isolates of Beauveria bassiana (Balsamo) Vuillemin were evaluated. Conidia were suspended in deionized water and half of each suspension was treated with microwave radiation to kill all the conidia. Conidia were tested for viability in non-microwaved suspensions in a mixture (ca. 1:1) of viable and non-viable conidial suspensions, and in the microwaved suspensions that contained all non-viable conidia. No significant differences were observed for the four isolates tested between germination tests on water and agar and viability tests conducted with FDA alone or FDA in combination with PI. One isolate of B. bassiana that had been damaged in storage was also tested. Differences were observed between the actual germination and the percentage of viability determined using FDA or FDA plus PI. Damaged conidia maintained a measure of viability and fluoresced green, but did not fully germinate. 相似文献
239.
Human β-globin mRNA precursors (pre-mRNAs) synthesized in vitro from a bacteriophage SP6 promoter/β-globin gene fusion are accurately and efficiently spliced when added to a HeLa cell nuclear extract. Under optimal conditions, the first intervening sequence (IVS 1) is removed by splicing in up to 90% of the input. pre-mRNA. Splicing requires ATP and in its absence the pre-mRNA is neither spliced nor cleaved at splice junctions. Splicing does not require that the pre-mRNA contain a correct 5′ or 3′ end, a 3′ poly A tail, or a 5′-terminal cap structure. However, capping of the pre-mRNA significantly affects the specificity of in vitro processing. In the absence of a cap approximately 30%–40% of the pre-mRNA is accurately spliced, and a number of aberrantly cleaved RNAs are also detected. In contrast, capped pre-mRNAs are spliced more efficiently and produce fewer aberrant RNA species. The specificity of splice-site selection in vitro was tested by analyzing pre-mRNAs that contain β-thalassemia splicing mutations in IVS 1. Remarkably, these mutations cause the same abnormal splicing events in vitro and in vivo. The ability to synthesize mutant pre-mRNAs and study their splicing in a faithful in vitro system provides a powerful approach to determine the mechanisms of RNA splice-site selection. 相似文献
240.
Barbara Płytycz 《Immunogenetics》1984,19(1):3-11
The major histocompatibility complex (MHC) zygosity of the field-collected frogs, Rana temporaria, was detected by progeny testing. Groups of sibling tadpoles were grafted with intrafamilial tail-tip allografts and the ratio of rapidly rejected allografts to slowly rejected ones was estimated. Twenty-five percent of parental frogs appeared to be MHC homozygotes. Thus, MHC homozygosity in natural frog populations seems to be considerably higher than in wild mouse populations. 相似文献