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1.
Summary Fifteen species of didymozoid trematodes are recorded form marine fishes off the Waltair coast, Bay of Bengal, India. These include three new genera, namely, Platocystoides, Indodidymozoon and Renodidymocystis and six new species, namely, Didymozoon lobatum from Euthynnus affinis, Allodidymozoon cylindricum from Sphyraena obtusata and S. picuda, A. operculare from Sphyraena obtusata and S. picuda, Indodidymozzon platycephali from Platycephalus scaber, Renodidymocystis yamagutii from Rastrelliger kanagurta and Metanematobothrioides branchialis from Pristipomoides typus. Other species reported are: Didymocystis wedli Ariola, 1902, Coeliodidymocystis kamegaii Yamaguti, 1970, Platocystoides polyaster (Job, 1962), Neometadidymozoon polymorphis (Oshmarin & Mamaev, 1963), Lobatocystis yaito Yamaguti, 1965, Metadidymozoon branchiale Yamaguti, 1970; Allonematobothrium epinepheli Yamaguti, 1965; Gonapodasmius spilonotopteri Yamaguti, 1970 and Pseudocolocyntotrema yaito Yamaguti, 1970. Two new combinations made are: Allodidymozoon apharyngi (Job, 1961) for Didymozoon apharyngi Job, 1961 and Platocystoides polyaster (Job, 1962) for Platocystis polyaster Job, 1962.  相似文献   
2.
The effect of intraperitoneal injection of imipramine hydrochloride on the activity of gamma-aminobutyric acid transaminase was determined in three regions of the rat brain.The cerebral hemispheres did not show a significant change in the activity of gamma-aminobutyric acid transaminase. Cerebellum and brain stem, both, however, showed a very significant decrease in the activity of the enzyme at 15 and 30 minutes after drug administration. At 90 minutes after drug administration, the activity of gamma-aminobutyric acid transaminase had returned to nearly control values.  相似文献   
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4.

Aims

To estimate the number of coronary heart disease (CHD) deaths potentially preventable in England in 2020 comparing four risk factor change scenarios.

Methods and Results

Using 2007 as baseline, the IMPACTSEC model was extended to estimate the potential number of CHD deaths preventable in England in 2020 by age, gender and Index of Multiple Deprivation 2007 quintiles given four risk factor change scenarios: (a) assuming recent trends will continue; (b) assuming optimal but feasible levels already achieved elsewhere; (c) an intermediate point, halfway between current and optimal levels; and (d) assuming plateauing or worsening levels, the worst case scenario. These four scenarios were compared to the baseline scenario with both risk factors and CHD mortality rates remaining at 2007 levels. This would result in approximately 97,000 CHD deaths in 2020. Assuming recent trends will continue would avert approximately 22,640 deaths (95% uncertainty interval: 20,390-24,980). There would be some 39,720 (37,120-41,900) fewer deaths in 2020 with optimal risk factor levels and 22,330 fewer (19,850-24,300) in the intermediate scenario. In the worst case scenario, 16,170 additional deaths (13,880-18,420) would occur. If optimal risk factor levels were achieved, the gap in CHD rates between the most and least deprived areas would halve with falls in systolic blood pressure, physical inactivity and total cholesterol providing the largest contributions to mortality gains.

Conclusions

CHD mortality reductions of up to 45%, accompanied by significant reductions in area deprivation mortality disparities, would be possible by implementing optimal preventive policies.  相似文献   
5.
Heat shock protein 27 controls apoptosis by regulating Akt activation   总被引:16,自引:0,他引:16  
Activation of the serine-threonine kinase Akt by cytokines, chemokines, and bacterial products delays constitutive neutrophil apoptosis, resulting in a prolonged inflammatory response. We showed previously that Akt exists in a signaling complex with p38 MAPK, MAPK-activated protein kinase-2 (MAPKAPK-2), and heat shock protein-27 (Hsp27); and Hsp27 dissociates from the complex upon neutrophil activation. To better understand the regulation of this signaling module, the hypothesis that Akt phosphorylation of Hsp27 regulates its interaction with Akt was tested. The present study shows that Akt phosphorylated Hsp27 on Ser-82 in vitro and in intact cells, and phosphorylation of Hsp27 resulted in its dissociation from Akt. Additionally, the interaction between Hsp27 and Akt was necessary for activation of Akt in intact neutrophils. Constitutive neutrophil apoptosis was accelerated by sequestration of Hsp27 from Akt, and this enhanced rate of apoptosis was reversed by introduction of constitutively active recombinant Akt. Our results define a new mechanism by which Hsp27 regulates apoptosis, through control of Akt activity.  相似文献   
6.
An organic extract from a marine crustacean D. avarus was examined for antiangiogenic activity by using the chick embryo chorioallantoic membrane (CAM) assay. The methanol extract (HCM) inhibited angiogenesis in a dose dependent manner. The extract was further fractionated by bioactivity-guided separation to purify the active fractions successively. This resulted in three fractions HCM1, HCM2 and HCM3. The 50% inhibition shown by HCM was 600 ng/disc, HCM1 was 100 ng/disc and of HCM3 was 2.7ng/disc. HCM3 which was separated by column chromatography and showed single spot on TLC was analysed by GLC and showed the presence of saturated and unsaturated fatty acids such as lauric, myristic, palmitic, stearic, oleic, linoleic. The antiangiogenic activity of the fatty acids obtained from a marine crustacean is reported for the first time.  相似文献   
7.
Parathyroid hormone inhibits sodium-phosphate cotransport in proximal renal tubule cells through activation of several kinases. We tested the hypothesis that the activity of these kinases was coordinated by an A kinase anchoring protein (AKAP) by demonstrating that the type II sodium-phosphate cotransporter (NaPi-4) physically associated with an AKAP and that this association was necessary for regulation of phosphate transport by parathyroid hormone. Immunoprecipitation with anti-NaPi-4 antiserum and glutathione S-transferase pull-down with GST-NaPi-4 showed that NaPi-4 associated with AKAP79, protein kinase A catalytic and regulatory subunits, and the parathyroid hormone receptor in opossum kidney cells. When the regulatory subunit of protein kinase A was uncoupled from the AKAP by a competing peptide, parathyroid hormone lost the ability to inhibit phosphate transport. This result was confirmed by co-transfecting HEK293 cells with the sodium-phosphate cotransporter and wild type AKAP, a mutant AKAP79, or the empty vector. 8-Bromo-cAMP was able to inhibit phosphate transport in cells expressing the wild type AKAP79 but not empty vector or mutant AKAP79. We conclude that parathyroid hormone inhibits proximal renal tubule sodium-phosphate cotransport through a signaling complex dependent upon an AKAP.  相似文献   
8.
The whole body ether extracts of a marine prawn Nematopaleamon tenuipes and two gastropods viz. Euchelus asper and Hemifusus pugilinus, obtained by Soxhlet extraction and cold percolation were tested for their effects on phagocytosis by in vitro (slide method) and by in vivo (carbon clearance) methods. Extract of E. asper exhibits immunostimulatory activity in vitro and immunosuppressant activity in vivo. The in vitro test for N. tenuipes and H. pugilinus shows biphasic activity, but the former shows immunostimulatory while the latter shows immunosuppresant activity in vivo test.  相似文献   
9.
Mitogen-activated protein kinase (MAPK)-activated protein kinase 2 (MAPKAPK2) mediates multiple p38 MAPK-dependent inflammatory responses. To define the signal transduction pathways activated by MAPKAPK2, we identified potential MAPKAPK2 substrates by using a functional proteomic approach consisting of in vitro phosphorylation of neutrophil lysate by active recombinant MAPKAPK2, protein separation by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and phosphoprotein identification by peptide mass fingerprinting with matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS) and protein database analysis. One of the eight candidate MAPKAPK2 substrates identified was the adaptor protein, 14-3-3zeta. We confirmed that MAPKAPK2 interacted with and phosphorylated 14-3-3zeta in vitro and in HEK293 cells. The chemoattractant formyl-methionyl-leucyl-phenylalanine (fMLP) stimulated p38-MAPK-dependent phosphorylation of 14-3-3 proteins in human neutrophils. Mutation analysis showed that MAPKAPK2 phosphorylated 14-3-3zeta at Ser-58. Computational modeling and calculation of theoretical binding energies predicted that both phosphorylation at Ser-58 and mutation of Ser-58 to Asp (S58D) compromised the ability of 14-3-3zeta to dimerize. Experimentally, S58D mutation significantly impaired both 14-3-3zeta dimerization and binding to Raf-1. These data suggest that MAPKAPK2-mediated phosphorylation regulates 14-3-3zeta functions, and this MAPKAPK2 activity may represent a novel pathway mediating p38 MAPK-dependent inflammation.  相似文献   
10.
Friedreich’s ataxia (FRDA) is an autosomal recessive neurodegenerative disorder caused by a GAA repeat expansion mutation within intron 1 of the FXN gene, resulting in reduced levels of frataxin protein. We have previously reported the generation of human FXN yeast artificial chromosome (YAC) transgenic FRDA mouse models containing 90–190 GAA repeats, but the presence of multiple GAA repeats within these mice is considered suboptimal. We now describe the cellular, molecular and behavioural characterisation of a newly developed YAC transgenic FRDA mouse model, designated YG8sR, which we have shown by DNA sequencing to contain a single pure GAA repeat expansion. The founder YG8sR mouse contained 120 GAA repeats but, due to intergenerational expansion, we have now established a colony of YG8sR mice that contain ~200 GAA repeats. We show that YG8sR mice have a single copy of the FXN transgene, which is integrated at a single site as confirmed by fluorescence in situ hybridisation (FISH) analysis of metaphase and interphase chromosomes. We have identified significant behavioural deficits, together with a degree of glucose intolerance and insulin hypersensitivity, in YG8sR FRDA mice compared with control Y47R and wild-type (WT) mice. We have also detected increased somatic GAA repeat instability in the brain and cerebellum of YG8sR mice, together with significantly reduced expression of FXN, FAST-1 and frataxin, and reduced aconitase activity, compared with Y47R mice. Furthermore, we have confirmed the presence of pathological vacuoles within neurons of the dorsal root ganglia (DRG) of YG8sR mice. These novel GAA-repeat-expansion-based YAC transgenic FRDA mice, which exhibit progressive FRDA-like pathology, represent an excellent model for the investigation of FRDA disease mechanisms and therapy.KEY WORDS: GAA repeat, Friedreich’s ataxia, FRDA, YG8sR, Mouse model  相似文献   
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