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251.
Ethanol introduced intragastrically (i.g.) in rats increased the pituitary-adrenocortical activity, measured indirectly through corticosterone concentration in blood serum. Since this increase reached only about 40% of the maximum hormone levels observed in that species after another stimuli, ethanol may be considered as a relatively weak stimulus. Ethanol induced also a significant decrease in serum free fatty acid (FFA) levels which was blocked totally by a prior intracerebroventricular (i.c.v.) administration of either H1- or H2-histamine receptor antagonists, mepyramine or metiamide and cimetidine. The ethanol-induced increase in serum corticosterone was insensitive to a central histamine H1- and H2-receptors blockade. Ethanol abolished the rise in serum FFA levels induced by an i.c.v. administration of histamine, pyridylethylamine (PEA)-a H1-receptor agonist, and dimaprit — a H2-receptor agonist. The histamine- and histamine-agonists induced increases of serum coricosterone were generally slightly intensified by a prior i.g. administration of ethanol.  相似文献   
252.
The effects of chloramphenicol (CAP) on rat adrenocortical cells were investigated by biochemical and stereological methods. It was found that administering 50 mg/kg of CAP every 12 hours provoked a persistent inhibition of the incorporation of 3H-leucine into mitochondrial proteins. Chronic treatment (up to 15 consecutive days) with this dose of CAP induced a significant decrease in the volume of the mitochondrial compartment, in the surface area of the outer and inner mitochondrial membranes and in the number of mitochondria per cell. These results confirm the hypothesis that the ACTH-induced maintenance of adrenocortical mitochondrial growth requires continuous mitochondrial DNA-dependent protein synthesis.  相似文献   
253.
Chromosomal rearrangements of the MYC locus, which often involve the IG loci, are recurrent events in multiple myeloma (MM) and plasma cell leukemia (PCL). We used dual-color fluorescence in situ hybridization (FISH) to characterize the breakpoint locations of chromosomal translocations/rearrangements involving the MYC locus at 8q24 found in a panel of 14 MM cell lines and 70 primary tumors (66 MM and 4 PCL). MYC locus alterations were observed in 21 cases: MYC/IG (mainly IGH@) fusions in 11 cell lines and three patients (2 MM and 1 PCL), and extra signals and/or abnormal MYC localizations in seven patients (5 MM and 2 PCL). Fourteen of these cases were investigated by FISH analyses by use of a panel of BAC clones covering about 6 Mb encompassing the MYC locus. The breakpoints were localized in a region 100-250 kb centromeric to MYC in four cases, a region 500-800 kb telomeric to the gene in four cases, and regions > or = 2 Mb centromeric or telomeric to MYC in five cases. Two different breakpoints were detected in the KMS-18 cell line, whereas the insertion of a MYC allele was found in a complex t(16;22) chromosomal translocation in the RPMI8226 cell line. Our data document a relatively high dispersion of 8q24 breakpoints in MM.  相似文献   
254.
Kava-Kava administration reduces anxiety in perimenopausal women   总被引:1,自引:0,他引:1  
OBJECTIVE: Disturbances of mood, such as anxiety and depression, increase in the perimenopausal period. Hormone replacement therapy or neuroactive drugs represent useful treatments for these disturbances but may be contraindicated or not accepted. Herein it was investigated the efficacy of Kava-Kava, an extract of Piper Methysticum, on mood of perimenopausal women. DESIGN: A 3-months randomized prospective open study investigating in perimenopausal women modifications induced by calcium supplementation (control; n=34), calcium plus Kava-Kava at the dose of 100 mg/day (n=15) or calcium plus Kava-Kava at the dose 200 mg/day (n=19). Anxiety was evaluated by the State Trait Anxiety Inventory (STAI); depression by the Zung's scale (SDS), and climacteric symptoms by the Greene's scale. Evaluations were performed at baseline and after 1 and 3 months. RESULTS: In the control group during the 3 months, anxiety, depression and climacteric symptoms tended to decline, but not significantly. During Kava-Kava anxiety declined (P<0.001) at 1 (-3.8+/-1.03) and 3 (-5.03+/-1.2) months, depression declined at 3 months (-5.03+/-1.4; P<0.002) and climacteric score declined (P<0.0006) at 1 (-2.87+/-1.5) and 3 (-5.38+/-1.3) months. Only the decline of anxiety induced by Kava-Kava was significantly greater than that spontaneously occurring in controls (P<0.009). CONCLUSIONS: The present data indicate that, in perimenopausal women, administration of Kava-Kava induces an improvement of mood, particularly of anxiety.  相似文献   
255.
Alterations of DNA mismatch repair (MMR) genes are involved in carcinogenesis of sporadic and inherited human cancers characterised by instability of DNA microsatellite sequences (MSI). MSI tumours are usually identified using molecular analysis. In the present investigation, hMLH1 and hMSH2 immunohistochemistry was tested in order to evaluate the utility of this method in predicting MMR deficiency. Colorectal (72), gastric (68), endometrial (44) and ovarian (17) carcinomas were independently evaluated for familial history, histological type of tumour, MSI status and immunohistochemical results. Loss of expression of either hMLH1 or hMSH2 was observed in 51 of 55 (92.8%) MSI tumours, while 145 of 146 microsatellite stable (MSS) tumours expressed both the hMLH1 and hMSH2 gene products. Independently of tumour site, an overall agreement between immunohistochemical and molecular results was observed in 15 hereditary non-polyposis colorectal cancer-related tumours. Among sporadic tumours, only 2 of 60 colorectal and 2 of 66 gastric carcinomas, displaying MSI, expressed both hMLH1 and hMSH2 gene products. All 39 endometrial and 16 ovarian tumours presented a concordant molecular and immunohistochemical profile. These data show that immunohistochemistry is an accurate and rapid method to predict the presence of defective DNA MMR genes and to identify both sporadic and familial MSI tumours.  相似文献   
256.
Sarcoidosis (SA) is a systemic granulomatous disorder of unknown etiology characterized by T helper 1-type inflammatory responses at sites of disease with signs of B cell hyperactivity. Like rheumatoid arthritis and diabetes, an infectious etiology has frequently been postulated but no single infectious trigger definitively identified. Polymorphic alleles at SLC11A1 have previously been associated with susceptibility to both the putative infectious agents and to these autoimmune disorders. We therefore investigated its candidacy as a genetic determinant of SA in Poland in an association-based study comparing 86 SA patients with 85 tuberculosis (TB) patients and 93 control subjects. The functional promoter (GT)(n) polymorphism and four of 10 other single nucleotide or insertion/deletion polymorphisms genotyped across SLC11A1 were informative in our sample. Consistent with previous autoimmune disease studies, allele 3 at the functional (GT)(n) promoter region repeat polymorphism was significantly associated with SA when compared with healthy controls (odds ratio 1.68; 95% CI: 1.01-2.81; P=0.04) or with TB patients (odds ratio 1.69; 95% CI: 1.042-0.78; P=0.03).  相似文献   
257.
Neonatal diabetes can either remit and hence be transient or else may be permanent. These two phenotypes were considered to be genetically distinct. Abnormalities of 6q24 are the commonest cause of transient neonatal diabetes (TNDM). Mutations in KCNJ11, which encodes Kir6.2, the pore-forming subunit of the ATP-sensitive potassium channel (K(ATP)), are the commonest cause of permanent neonatal diabetes (PNDM). In addition to diabetes, some KCNJ11 mutations also result in marked developmental delay and epilepsy. These mutations are more severe on functional characterization. We investigated whether mutations in KCNJ11 could also give rise to TNDM. We identified the three novel heterozygous mutations (G53S, G53R, I182V) in three of 11 probands with clinically defined TNDM, who did not have chromosome 6q24 abnormalities. The mutations co-segregated with diabetes within families and were not found in 100 controls. All probands had insulin-treated diabetes diagnosed in the first 4 months and went into remission by 7-14 months. Functional characterization of the TNDM associated mutations was performed by expressing the mutated Kir6.2 with SUR1 in Xenopus laevis oocytes. All three heterozygous mutations resulted in a reduction in the sensitivity to ATP when compared with wild-type (IC(50) approximately 30 versus approximately 7 microM, P-value for is all <0.01); however, this was less profoundly reduced than with the PNDM associated mutations. In conclusion, mutations in KCNJ11 are the first genetic cause for remitting as well as permanent diabetes. This suggests that a fixed ion channel abnormality can result in a fluctuating glycaemic phenotype. The multiple phenotypes associated with activating KCNJ11 mutations may reflect their severity in vitro.  相似文献   
258.
Identification of the membrane protein of porcine epidemic diarrhea virus   总被引:4,自引:0,他引:4  
Sequence information on the genome of porcine epidemic diarrhea virus (PEDV) has only recently been determined. In contrast, very little is known about the viral proteins. In the present report we have identified the membrane glycoprotein (M) of PEDV by use of rabbit anti-peptide sera and transient expression of the cloned M gene in Vero cells and by expression in the baculovirus system. The native M protein of PEDV is incorporated into virions, is N-glycosylated, and migrates with a relative mobility (Mr) of 27 k in polyacrylamide gels. In contrast, the M protein synthesized by recombinant baculoviruses migrates with a Mr of 23 k, that is, with identical mobility as the deglycosylated product of PEDV. Thus, it appears that M protein specified by the recombinant baculovirus is poorly, if at all, glycosylated. Using monoclonal antibodies and rabbit antipeptide sera specific for the N and C termini of the M protein, we were able to show that a 19 k band detected in PEDV-infected cells but not in virions represented a fragment of M from which the C terminus had been cleaved off. Finally, by electron microscopy and immunogold labelling, the relative orientation of M within the virion envelope was determined as NexoCcyt. In conclusion, all of these data strongly support the hypothesis that PEDV should be classified with the group I coronaviruses.  相似文献   
259.
BACKGROUND: Clinical correlates of HerpeSelect ELISA index values are poorly understood. OBJECTIVES: This study was designed to determine the effects of time of infection, test variability, and antibody avidity on index values. STUDY DESIGN: Sera (N=313) from 81 patients with new HSV-2 infections and 236 sera from 32 patients with long-standing (median 11.3 years) HSV-2 were tested by HerpeSelect HSV-2 ELISA. High positive, low positive and negative controls were run on 42 test plates to establish test variability. RESULTS: Index values tended to rise after infection, peaking a median of 9-10 weeks post-infection (range 8-323 days). Of 32 patients with established HSV-2 infections, 7 (22%) had at least one low index value (>1.1 to < or =3.5), and one had a transient seroreversion event. Test variability of index values was substantially lower than inter- or intra-patient variability. Median antibody avidity was higher in sera with high versus low index values in established infections, but unrelated to index value in patients with early infections. CONCLUSIONS: Index values or index value changes are not absolute indicators of early versus established HSV-2 infection or solely a function of test variability. Low antibody avidity may contribute to low index values once infection is established.  相似文献   
260.
It has been suggested that one key feature of mitochondrial permeability transition (PT) regulation is its control by the proton electrochemical gradient and that depolarization favors pore opening, swelling, and reactive oxygen species (ROS) production. Moreover, ROS have been suggested to facilitate the process of mitochondrial PT pore opening. The aim of this study was to show that collapsing the mitochondrial membrane potential with the mitochondrial uncoupler, carbonyl cyanide p-(trifluoromethoxy) phenylhydrazone (FCCP), at concentrations of up to 10 microM, does not induce mitochondrial swelling and, in fact, stabilizes mitochondria exposed to oxidant, protecting them from tert-butyl hydroperoxide (TBH)-induced high-amplitude swelling. FCCP decreased polyethylene glycol-induced mitochondrial contraction following exposure to TBH, indicating closing of the PT mega-channel. In the presence of the calcium uniporter inhibitor ruthenium red, FCCP induced PT due to suppression of calcium efflux. Under PT-favorable conditions, ROS production was evaluated in mitochondria following treatments with TBH, inorganic phosphate, or FCCP (with or without ruthenium red). FCCP alone and in combination with ruthenium red attenuated mitochondria-derived ROS production. FCCP also decreased the augmented ROS production induced by inorganic phosphate. It is concluded that mitochondrial depolarization protects and prevents high-amplitude swelling and PT-derived ROS production.  相似文献   
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