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61.
62.
This work reports the results of an environmental survey carried out in an industrial area in the Province of Turin: its main aim is to assess the levels of iron and aluminium in the outside air during the period from July to September to assess the influence of industrial activity (a cast-iron and aluminium foundry) which is interrupted during the month of August, on the level of metals present in the air. Conducting the analysis during this period of time made it possible to avoid the confounding effect of pollution due to domestic central heating. The measurements were taken from nine areas at different distances from the foundry in the area and according to the direction of the prevailing winds, as deduced from the historical data. The results of this survey show a statistically significant difference in iron and aluminium levels in the outside air in the geographic areas between the two main periods examined: during August (no foundry activity) v/s July-September (foundry activity). The values recorded are: Aluminium 0.4+/-0.45 microg/m(3) v/s 1.12+/-1.29 microg/m(3) (p<0.0001); Iron 0.95+/-0.56 microg/m(3) v/s 1.6+/-1.0 microg/m(3) (p<0.0001). There were no statistically significant differences between the nine sampling points from the point of view of the sampling sites, climate conditions and wind directions. We found no correlation with car traffic, in terms of the number of vehicles, and metals. The values of iron tended to be higher in the areas farther away from the foundry site in the areas located along the path of the prevailing winds.  相似文献   
63.
The fertility of three bulls carrying different Robertsonian translocations (rob(1;29), rob(14;17) and rob(26;29)) was evaluated. Oocytes-cumulus complexes obtained from slaughterhouse-derived ovaries were matured and then fertilised in vitro with frozen/thawed seminal material from the above mentioned subjects, and from control bulls with normal karyotype. An assessment was first made of the concentration, vitality and acrosome integrity of the seminal material to be sure that possible differences in the results of the in vitro fertilisation experiments were not due to seminal material quality. The results of the experiments, evaluated by the percentage of cleaved embryos and blastocysts per cleaved embryo, indicated that the three bulls carrying Robertsonian translocations had similar fertilising power and semen qualitative parameters to the controls. These data suggest that neither gametogenesys impairment nor decreased spermatozoa fertilising capacity is responsible for the reduced fertility in bulls with Robertsonian translocations. What the data do confirm is that the observed in vivo hypofertility for karyologically abnormal bulls is mainly due to early embryonic mortality.  相似文献   
64.
65.
We developed a rapid, practical and non-toxic salting-out method for the extraction of DNA from marine organisms, and tested it on two representative species of Porifera and Cnidaria, both living in association with symbiotic zooxanthellae. We tested the efficiency of the protocol by comparing the output of the method for fresh tissue, frozen tissue and tissue stored in ethanol. It proved to be effective for extracting DNA in the case of the methods of preservation considered here, and for obtaining quantities of DNA comparable to those obtained via the traditional approach. The DNA from both species was of good quality. The DNA obtained was amplified by PCR using specific primers for the large ribosomal subunit, allowing the identification of the presence of both the host and symbiont genomes.  相似文献   
66.
The neurosteroid allopregnanolone, a reduced metabolite of progesterone, induces anxiolytic effects by enhancing GABA(A) receptor function. Neuropeptide Y (NPY) and GABA are thought to interact functionally in the amygdala, and this interaction may be important in the regulation of anxiety. By using Y(1)R/LacZ transgenic mice, which harbour a fusion construct comprising the promoter of the mouse gene for the Y(1) receptor for NPY linked to the lacZ gene, we previously showed that long-term treatment with benzodiazepine receptor ligands modulates Y(1) receptor gene expression in the medial amygdala. We have now investigated the effects of prolonged treatment with progesterone or allopregnanolone on Y(1)R/LacZ transgene expression, as determined by quantitative histochemical analysis of beta-galactosidase activity. Progesterone increased both the cerebrocortical concentration of allopregnanolone and beta-galactosidase expression in the medial amygdala. Finasteride, a 5alpha-reductase inhibitor, prevented both of these effects. Long-term administration of allopregnanolone also increased both the cortical concentration of this neurosteroid and transgene expression in the medial amygdala. Treatment with neither progesterone nor allopregnanolone affected beta-galactosidase activity in the medial habenula. These data suggest that allopregnanolone regulates Y(1) receptor gene expression through modulation of GABA(A) receptor function, and they provide further support for a functional interaction between GABA and neuropeptide Y in the amygdala.  相似文献   
67.
There is increasing evidence that epithelial-vascular interactions are essential for tissue patterning. Here we identified components of the molecular cross talk between respiratory epithelial cells and pulmonary capillaries necessary for the formation of the gas exchange surface of the lung. Selective inactivation of the Vegf-A gene in respiratory epithelium results in an almost complete absence of pulmonary capillaries, demonstrating the dependence of pulmonary capillary development on epithelium-derived Vegf-A. Deficient capillary formation in Vegf-A deficient lungs is associated with a defect in primary septae formation, a morphogenetic process critical for distal lung morphogenesis, coupled with suppression of epithelial cell proliferation and decreased hepatocyte growth factor (Hgf) expression. Lung endothelial cells express Hgf, and selective deletion of the Hgf receptor gene in respiratory epithelium phenocopies the malformation of septae, confirming the requirement for epithelial Hgf signaling in normal septae formation and suggesting that Hgf serves as an endothelium-derived factor that signals to the epithelium. Our findings support a mechanism for primary septae formation dependent on reciprocal interactions between respiratory epithelium and the underlying vasculature, establishing the dependence of pulmonary capillary development on epithelium-derived Vegf-A, and identify Hgf as a putative endothelium-derived factor that mediates the reciprocal signaling from the vasculature to the respiratory epithelium.  相似文献   
68.
Surveillance of illegal use of steroids hormones in cattle breeding is a key issue to preserve human health. To this purpose, an integrated approach has been developed for the analysis of plasma and urine from calves treated orally with a single dose of a combination of the androgenic steroids boldenone and boldione. A quantitative estimation of steroid hormones was obtained by LC-APCI-Q-MS/MS analysis of plasma and urine samples obtained at various times up to 36 and 24 h after treatment, respectively. These experiments demonstrated that boldione was never found, while boldenone alpha- and beta-epimers were detected in plasma and urine only within 2 and 24 h after drug administration, respectively. Parallel proteomic analysis of plasma samples was obtained by combined 2-DE, MALDI-TOF-MS and muLC-ESI-IT-MS/MS procedures. A specific protein, poorly represented in normal plasma samples collected before treatment, was found upregulated even 36 h after hormone treatment. Extensive mass mapping experiments proved this component as an N-terminal truncated form of apolipoprotein A1 (ApoA1), a protein involved in cholesterol transport. The expression profile of ApoA1 analysed by Western blot analysis confirmed a significant and time dependent increase of this ApoA1 fragment. Then, provided that further experiments performed with a growth-promoting schedule will confirm these preliminary findings, truncated ApoA1 may be proposed as a candidate biomarker for steroid boldenone and possibly other anabolic androgens misuse in cattle veal calves, when no traces of hormones are detectable in plasma or urine.  相似文献   
69.
Tyrosine hydroxylase, a key enzyme in the biosynthesis of catecholamines, was previously shown to be phosphorylated on four distinct serine residues in PC12 cell cultures, each one being specific for the kinase system involved (McTigue, M., Cremins, J., and Halegoua, S. (1985) J. Biol. Chem. 260, 9047-9056). A cAMP- and Ca2+-independent protein kinase was found to be associated with tyrosine hydroxylase purified from rat pheochromocytoma tumor. The use of this activity and the availability of a large amount of purified tyrosine hydroxylase allowed identification of the site phosphorylated by this kinase activity. A peptide of 1.5 kDa (about 12 residues long), carrying the phosphorylation site, was released from 32P-labeled tyrosine hydroxylase by limited proteolysis with trypsin. This peptide was isolated from trypsinized tyrosine hydroxylase by sequential gel filtration and ion exchange chromatographies. Analysis by thin layer chromatography of an acid hydrolysate of the peptide revealed that it contained phosphoserine. The sequence determination of the peptide showed that it corresponded to the residues 38-45 in the tyrosine hydroxylase primary structure (Arg-Gln-Ser(P)-Leu-Ile-Glu-Asp-Ala). Thus, the associated kinase phosphorylated Ser-40, one of the phosphorylation sites for the cAMP-dependent protein kinase also found in rat pheochromocytoma tumors. These results are compared to those recently appearing in a report by Campbell et al. (Campbell, D. G., Hardie, D. G., and Vulliet, P. R. (1986) J. Biol. Chem. 261, 10489-10492).  相似文献   
70.
The injection of mature T cells into a tolerant or immunocompromised allogeneic host animal produces a graft versus host response (GVHR) that can result in splenomegaly, immunosuppression and death of the host animal. We demonstrate here that lymphocytes from T cell receptor beta-chain (TCR-beta) transgenic mice, in which the expression of the transgene inhibits endogenous beta- and gamma-gene rearrangements and thus causes abnormal T cell development, are unable to mediate a GVHR. The GVHR was measured after the injection of lymphocytes from transgenic mice into normal F1 mice and also after transplantation of bone marrow and lymphocytes from transgenic mice into lethally irradiated F1 recipients. In both systems, cells from transgenic mice failed to produce a significant GVHR. Cells from the transgenic mice were able to recognize the foreign histocompatibility Ag of the host in vitro and in vivo although the transgenic mice rejected skin grafts more slowly than controls. Thus, lymphocytes from transgenic mice were unable to produce a GVHR despite the presence of alloreactive T cells. These results suggest that lymphocytes from TCR-beta transgenic mice fail to mediate a GVHR either because lymphocytes with a single transgenic TCR-beta chain have a limited ability to recognize allogeneic cells in vivo or because the transgenic mice lack lymphocyte subsets that are important for the mediation of a GVHR.  相似文献   
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