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971.
Milczarek R Sokolowska E Hallmann A Klimek J 《Molecular and cellular biochemistry》2007,295(1-2):105-111
In pregnant females, placenta is the most important source of lipid hydroperoxides and other reactive oxygen species (ROS).
The increased production of lipid peroxides is often linked to preeclampsia. In our study, we revealed that NADPH- and iron-dependent
lipid peroxidation in human placental microsomes (HPM) occurred. In the presence of Fe2+ ion, HPM produced small amounts of thiobarbituric acid-reactive substances (TBARS) – a final product of lipid peroxidation.
NADPH caused a strong increase of iron stimulated TBARS formation. TBARS formation was inhibited by superoxide dismutase,
butylated hydroxytoluene and α-tocopherol but not by mannitol or catalase. TBARS and superoxide radical production was inhibited
in similar manner by cytochrome P450 inhibitors. The results obtained led us to the following conclusions: (1) microsomal
lipid peroxidation next to mitochondrial lipid peroxidation may by an important source of lipid hydroperoxides in blood during
pregnancy and (2) superoxide radical released by microsomal cytochrome P450 is an important factor in NADPH- and iron-dependent
lipid peroxidation in HPM. 相似文献
972.
The effect of Dithane M-45 (dithiocarbamate fungicide; active substance: mancozeb) was studied on microarthropod fauna inhabiting
dead wood. Although the exposure was almost never 100% lethal for the majority of observed taxa, almost all (Mesostigmata,
Oribatida, some Uropodina, Actinedida, Collembola and Diplopoda) showed very high correlation between concentration of the
fungicide and mortality (r > 0.86). Only Stigmaeidae showed low correlation (r = 0.293). For the majority of taxa LC50 values were close to the concentrations used during agrochemical activities in woods. Only Trachytes aegrota showed full susceptibility to the fungicide within the range of recommended field concentrations used in forestry (characterised
by the low LC95 value). Tolerance of mesostigmatid and oribatid mites was found to differ between juveniles and adults, but not consistently.
Related Uropodina species varied in susceptibility to the fungicide. 相似文献
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977.
Effects of PACAP and VIP on cyclic AMP formation in rat neuronal and astrocyte cultures under normoxic and hypoxic condition 总被引:1,自引:0,他引:1
Pituitary adenylate cyclase-activating polypeptide (PACAP) and vasoactive intestinal peptide (VIP) concentration (0.001-1000 nM)-dependently stimulated cyclic AMP production in rat primary neuronal and glial cell (astrocyte) cultures. The actions of both peptides were much more pronounced in astrocytes than in neuronal cultures. Stimulatory effects of PACAP and VIP on cyclic AMP formation were significantly smaller in cell cultures subjected to 24h lasting hypoxic conditions, induced either chemically (100 microM cobalt chloride) or by low 3% oxygen hypoxia, compared to the normoxic condition (95% air and 5% CO(2)). This picture contrasted with the effects of forskolin that were similar under normoxic and hypoxic conditions. It is suggested that hypoxia leads to changes in PACAP- and VIP-driven cyclic AMP-dependent signaling in the rat brain by influencing molecular processes likely occurring at the level of receptor protein or receptor-Gs protein coupling. 相似文献
978.
Yotova V Lefebvre JF Kohany O Jurka J Michalski R Modiano D Utermann G Williams SM Labuda D 《Human genetics》2007,122(5):431-443
Genetic variability of the compound interrupted microsatellite DXS1238, in intron 44 of the dystrophin gene, provides evidence
for a complex structure of the ancestral population that led to the emergence of modern humans. We sequenced DXS1238 in 600
X-chromosomes from all over the world. Forty four percent of African-specific chromosomes belong to the ancestral lineage
that did not participate in the out-of-Africa expansion and subsequent colonization of other continents. Based on the coalescence
analysis these lineages separated from those that contributed to the out-of-Africa expansion 366 ± 136 thousands years ago
(Kya). Independently, the analysis of the variance in the repeat length and of the decay of the ancestral alleles of the two
DXS1238 repeats, GT and GA, dates this separation at more than 200 Kya. This suggests a complex demographic history and genetic
structure of the African melting pot that led to the emergence of modern humans and their out-of-Africa migration. The subsequent
subdivisions of human populations among different continents appear to be preceded by even more structured population history
within Africa itself, which resulted from a restricted gene flow between lineages allowing for genetic differences to accumulate.
If the transition to modern humans occurred during that time, it necessarily follows that genes associated with this transformation
spread between subpopulations via gene flow. Otherwise, in spite of subsequent anatomical variation, Homo sapiens as a species could have emerged in Africa already between 300 and 200 Kya, i.e. before the mitochondrial DNA and well before
the Y-chromosome most recent common ancestors.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
979.
Bolanowski M Bar-Andziak E Kos-Kudła B Krzyzanowska-Swiniarska B Lewiński A Lomna-Bogdanov E Milewicz A Sowiński J Zgliczyński W 《Endokrynologia Polska》2007,58(4):350-3; discussion 354-5
Consensus statement of the Polish Society of Endocrinology, regarding presurgical somatostatin analogs in acromegaly has been presented. It is suggested to administer depot somatostatin analog (Octreotide LAR at the dose 20 mg and then 30 mg or equivalent doses of Lanreotide Autogel 90/120 mg every 4 weeks) in order to normalize or suppress to a maximal extent GH and IGF-1 concentrations. The period of therapy in case of microadenoma would be at least 3 months (targets: biochemical improvement, reduced risk of disease's complications, perioperative risk reduction, inhibition of tumor growth). The period of therapy in case of macroadenoma would be at least 6 months, until maximal possible reduction of GH and IGF-1 concentrations (targets: tumor shrinkage, biochemical improvement, reduced risk of disease's complications, perioperative risk reduction). Using an uniform approach in a group, as numerous as possible, of treated patients would allow objective evaluation of long-term efficacy of the treatment. 相似文献
980.
Matuszewska G Marek B Kajdaniuk D Przywara-Chowaniec B Jarzab J Jarzab B 《Endokrynologia Polska》2007,58(5):384-396
INTRODUCTION: Patients with differentiated thyroid carcinoma have to undergo radical surgical treatment, which includes total thyreoidectomy, radioiodine therapy and a life-time suppressive therapy with L-thyroxine. The aim of this study was a prospective evaluation of left ventricular hypertrophy during L suppressive-thyroxine treatment in patients treated for differentiated thyroid carcinoma. MATERIAL AND METHODS: The examined group comprised 50 patients with differentiated thyroid carcinoma, treated by total thyroidectomy and 131I therapy. Echocardiographic measurements were needed for estimation of left ventricular mass and its index, according to recommendations of American Echocardiography Society. RESULTS: During two-years long suppressive therapy we observed a significant rise in left ventricular mass. In woman group left ventricular mass was increased from 168+/-39 g to 204+/-45 g (p<0.001) and in men from 205+/-60 to 320+/-21 g. Likewise, left ventricular mass index was increased in women group from 96+/-18 g/m(2) to 116+/-25 g/m(2) (p<0.001) and in men group from 107+/-37 g/m(2) to 158+/-28 g/m(2). Simultaneous treatment with bisoprolol caused a regression of left myocardial hypertrophy. Already after 6 months of simultaneous treatment with L-thyroxin and bisoprolol, for left ventricular mass was reduced to normal: in woman 165+/-35 g, and in men to 178+/-38 g. Analogous results were obtained left ventricular mass index. After 6 months it was reduced to 94+/-12 g/m(2) in woman and in men to 132+/-32 g/m(2). CONCLUSIONS: 1. In differentiated thyroid cancer patients, treated postoperatively with L-thyroxine suppressive therapy, left ventricular hypertrophy is observed already during the first year of suppressive therapy and progresses during the next year of treatment. 2 Addition of a beta-adrenergic antagonist to suppressive doses of L-thyroxine causes a regression of left ventricular hypertrophy, thus, beta-adrenergic antagonists should be administered in this group of patients. 相似文献