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OBJECTIVE: To study the production and interrelations of maternal and neonatal cytokines (IL-6 and TNF-alpha) during labor, after vaginal delivery and at three months after delivery. METHOD: The unstimulated concentrations of cytokines in the supernatants of whole-blood cultures and concentrations after PMA (phorbol 12-myristate 13-acetate) and concanavalin (conA) stimulation were determined by enzyme-linked immunosorbent assays (ELISAs). The blood samples were from the peripheral veins of 27 healthy women during term labor and immediately after delivery and three months after delivery. Neonatal samples were taken at birth (cord blood) and three months after delivery. RESULTS: IL-6 responses to stimulation were increased in the parturients and in umbilical cord blood at delivery compared with maternal and neonatal samples obtained 3 months postpartum. In contrast, the production of maternal TNF-alpha in peripheral blood was down-regulated at delivery compared with values 3 months postpartum. After an IL-6 and TNF-alpha burst in umbilical cord samples, neonatal cytokine production was at a low level three months after delivery. IL-6 production tended to be higher in both umbilical cord blood as well as in maternal samples after delivery in women who were younger. In addition, TNF-alpha production in umbilical cord blood was significantly higher in those women who were younger. CONCLUSIONS: The production of IL-6 was up-regulated in both the maternal and in umbilical cord blood at delivery. The production of TNF-alpha was up-regulated in umbilical cord blood compared with neonatal values 3 months after birth. Maternal age had effects on IL-6 and TNF-alpha production at delivery.  相似文献   
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The genotoxic effects of gliotoxin, a known fungal secondary metabolite, were studied. Gliotoxin was purified from cultivation medium of Aspergillus fumigatus isolated from the indoor air of a moisture problem house. The genotoxicity of gliotoxin was assessed both in bacterial test systems including bacterial repair assay, Ames Salmonella assay and SOS-chromotest, and in mammalian cells using single cell gel (SCG) electrophoresis assay and sister-chromatid exchange (SCE) test. Gliotoxin was found to be genotoxic in the bacterial repair assay but, not in the Salmonella test or SOS-chromotest. A dose-related increase in DNA damage was observed in mouse RAW264.7 macrophages exposed to gliotoxin for 2h in plain medium in the SCG assay. In contrast to the positive response in the SCG assay, gliotoxin did not induce any clear, dose-related increase in SCEs in Chinese hamster ovary (CHO) cells.  相似文献   
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The International Journal of Life Cycle Assessment - This paper studies the carbon footprint and water scarcity footprint (WSF) of a milk protein, beta-lactoglobulin, produced by cellular...  相似文献   
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We have investigated the local and regional scale genetic structure of Siberian primrose (Primula nutans) populations in Northern Europe. The genetic diversity and structure of fifteen populations sampled from the Bothnian Bay in Finland, the Barents Sea in Norway and the White Sea in Russia were assessed using eleven microsatellite markers. We investigated the distribution of genetic variation within and between populations, and studied the local genetic structure using spatial autocorrelation analysis. We found very low genetic and allelic diversity in the Bothnian Bay and Barents Sea populations, and only slightly higher in the White Sea population. The level of genetic differentiation between the regions was very high, whereas differentiation between the populations within the regions was moderate. We found no spatial structuring of populations in any region suggesting efficient dispersal on a local scale. Clonal reproduction seemed to have no effect on genetic structure.  相似文献   
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The role of endogenous benzodiazepine receptor ligands in the pathogenesis of hepatic encephalopathy was studied in humans and in rat models of hepatic encephalopathy. Endogenous benzodiazepine ligands were extracted from rat brain and human CSF by acid treatment and purification by HPLC. Detection and partial characterization of these endogenous benzodiazepine ligands were carried out using both radioreceptor binding assays and radioimmunoassays with anti-benzodiazepine antibodies. Four different benzodiazepine receptor ligands were identified in human and rat tissue, two of which may be diazepam and desmethyldiazepam, based on elution profiles and anti-benzo-diazepine antibody reactivity. Human CSF and serum from patients with hepatic encephalopathy contained approximately 10 times more endogenous benzodiazepine receptor ligand than CSF from controls or nonencephalopathic patients with liver disease. The levels of brain benzodiazepine receptor ligand compounds were also increased approximately 10-fold in rats suffering from fulminant hepatic failure, but not in rats with portacaval shunts, a model of chronic hepatic disease. The increased concentrations of these substances could be behaviorally significant and may contribute to the pathogenesis of hepatic encephalopathy.  相似文献   
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Deficiency of acid sphingomyelinase (ASM), an enzyme responsible for producing a pro-apoptotic second messenger ceramide, has previously been shown to promote the survival of fetal mouse oocytes in vivo and to protect oocytes from chemotherapy-induced apoptosis in vitro. Here we investigated the effects of ASM deficiency on testicular germ cell development and on the ability of germ cells to undergo apoptosis. At the age of 20 weeks, ASM knock-out (ASMKO) sperm concentrations were comparable with wild-type (WT) sperm concentrations, whereas sperm motility was seriously affected. ASMKO testes contained significantly elevated levels of sphingomyelin at the age of 8 weeks as detected by high-performance, thin-layer chromatography. Electron microscopy revealed that the testes started to accumulate pathological vesicles in Sertoli cells and in the interstitium at the age of 21 days. Irradiation of WT and ASMKO mice did not elevate intratesticular ceramide levels at 16 h after irradiation. In situ end labeling of apoptotic cells also showed a similar degree of cell death in both groups. After a 21-day recovery period, the numbers of primary spermatocytes and spermatogonia at G2 as well as spermatids were essentially the same in the WT and ASMKO testes, as detected by flow cytometry. In serum-free cultures both ASMKO and WT germ cells showed a significant increase in the level of ceramide, as well as massive apoptosis. In conclusion, ASM is required for maintenance of normal sphingomyelin levels in the testis and for normal sperm motility, but not for testicular ceramide production or for the ability of the germ cells to undergo apoptosis.  相似文献   
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Receptor tyrosine kinase aberrations are implicated in the genesis of gliomas. We investigated expression and amplification of KIT, PDGFRA, VEGFR2, and EGFR in 87 gliomas consisting of astrocytomas, anaplastic astrocytomas, oligodendrogliomas, or oligoastrocytomas in tumor samples collected at the time of the diagnosis and in samples of the same tumors at tumor recurrence. Gene amplifications were investigated using either chromogenic in situ hybridization or fluorescence in situ hybridization, and protein expression using immunohistochemistry. In samples collected at glioma diagnosis, KIT and PDGFRA amplifications were more frequent in anaplastic astrocytomas than in astrocytomas, oligodendrogliomas, and oligoastrocytomas [28% versus 5% (P = 0.012) and 33% versus 2% (P = 0.0008), respectively]. VEGFR2 amplifications occurred in 6% to 17% of the gliomas at diagnosis, and EGFR amplifications in 0% to 12%. Amplified KIT was more frequently present in recurrent gliomas than in newly diagnosed gliomas (P = 0.0066). KIT amplification was associated with KIT protein expression and with presence of PDGFRA and EGFR amplifications both at the time of the first glioma diagnosis and at tumor recurrence, and with VEGFR2 amplification at tumor recurrence. Three (4%) primary gliomas and 10 (14%) recurrent gliomas that were evaluable for coamplification of KIT, PDGFRA, and VEGFR2 showed amplification of at least two of these genes; the amplicon contained amplified KIT in all 13 cases. In conclusion, besides glioblastoma, amplified KIT, PDGFRA, and VEGFR may also occur in lower-grade gliomas and in their recurrent tumors. It is currently not known whether specific tyrosine kinase inhibitors are effective in the treatment of such gliomas.  相似文献   
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In the Baltic Sea, herring (Clupea harengus membras) spawns in the littoral zone, where its eggs are attached to algae or vascular plants. Field studies indicate that egg mortality can be very high (up to 100%) in eggs that are attached to red algae (Rajasilta et al., 1989, 1993). Because high mortality can be due to allelochemical effects of the algae, we studied the mortality of herring eggs on different algal substrates experimentally. Four types of substrates were tested: fresh Cladophora and Furcellaria, and Furcellaria that had decomposed six days or 23 days. The incubation time in the experiments was 3 days and incubation temperature 12–13 oC (ca. 700–800 h-degrees). The results were in accordance with observations made in field studies and indicated significant differences among the substrate types. In eggs attached to fresh Cladophora, mortality was significantly lower (mean=2.8%; n=20) than in those attached to Furcellaria, independently of the treatment of the algae. The highest values of mortality (mean=14.4%; n=20) were found in eggs attached to Furcellaria that had decomposed over a six days’ period. This suggested that Furcellaria contain some chemical substances, which can cause mortality in herring embryos and the effect seems to be dependent on the state of decomposition of the algae.  相似文献   
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