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1.
2.
The modulation of drug metabolising enzymes by Masheri extract (ME) and Benzo(a)Pyrene [B(a)P] was studied in male Sprague Dawley rats fed different dietary protein levels. Two groups of 21 days old male Sprague Dawley rats were put on a high protein diet (SHP) with 20% Casein, and a low protein diet (SLP) with 3% Casein semisynthetic based diets for 12 weeks. The SLP fed animals showed lower basal levels of the Phase I activating enzymes viz. Cytochrome P450, Benzo(a)Pyrene hydroxylase, Benzphetamine demethylase and Phase II glutathione detoxification system viz. Glutathione (GSH) and Glutathione-S-transferase. ME and B(a)P treatment significantly depleted the glutathione detoxification system in the SLP group whereas an opposite effect was observed in the SHP group. Interstingly, ME and B(a)P treated rats in the SLP group showed a higher percent increase in the hepatic and pulmonary Phase I enzyme activities than those observed in the treated ME/B(a)P treated SHP rats. Furthermore, both ME and B(a)P significantly decreased the hepatic pool of vitamin A while a concomittant increase in that of vitamin C was observed.  相似文献   
3.
Classical and anaplastic seminoma: difference in survival   总被引:1,自引:0,他引:1  
Bobba  VS; Mittal  BB; Hoover  SV; Kepka  A 《Radiology》1988,167(3):849-852
Classical and anaplastic seminoma are traditionally treated with radiation therapy and are said to have the same prognosis. A retrospective study was undertaken of 90 seminoma patients treated with radiation therapy between 1961 and 1985. The classical group consisted of 71 patients of whom 50 had stage I and 21 had stage II disease. The anaplastic group consisted of 19 patients of whom ten had stage I and nine had stage II disease. The median follow-up time was 64 months for the entire group. The 10-year relapse-free survival rate for the classical group was 94% and for the anaplastic group was 70% (P less than .05). For patients with classical stage I disease, the relapse-free actuarial survival rate was 98%; for patients with anaplastic stage I disease, it was 64% (P less than .02). For the classical stage II disease group, the relapse-free actuarial survival rate was 84% and for the anaplastic stage II disease group, 75% (P less than .70). Four patients in the classical group (6%) had relapses; of these, one patient had local recurrence of tumor, and three had distant metastases. In the anaplastic group, four patients (21%) had relapses; two patients had local recurrence of tumor, and two had distant metastases. Therefore the data suggest a difference in survival and relapse rates between classical and anaplastic seminoma.  相似文献   
4.
白玉杰  Seetha SV  Vamla B  高庆生 《医学争鸣》2003,24(20):1845-1848
目的:应用酵母双杂交方法筛选BRCA2相互作用蛋白编码基因,验证其相互作用并研究其功能联系。方法:以BRCA2基因3′端片段构建酵母双杂交质粒,筛选正常人乳腺上皮细胞cDNA库,获得编码相互作用蛋白的基因,采用免疫共沉淀、哺乳细胞双杂交和荧光酶测定等方法进一步验证蛋白间相互作用和功能联系.结果:采用酵母双杂交系统筛选,获得了多个编码BRCA2相互作用蛋白的基因,其中包括已知的FHL2蛋白;免疫共沉淀和哺乳动物细胞双杂交试验显示BRCA2和FHL2在体内特异性结合,并证实FHL2在体内形成同源二聚体;转录活性分析发现BRCA2与FHL2有协同转录激活作用。结论:发现BRCA2与FHL2蛋白间相互作用和功能联系,为BRCA2功能研究提供了新的方向。  相似文献   
5.
The tumour suppressor gene PTEN , which maps to 10q23.3 and encodes a 403 amino acid dual specificity phosphatase (protein tyrosine phosphatase; PTPase), was shown recently to play a broad role in human malignancy. Somatic PTEN deletions and mutations were observed in sporadic breast, brain, prostate and kidney cancer cell lines and in several primary tumours such as endometrial carcinomas, malignant melanoma and thyroid tumours. In addition, PTEN was identified as the susceptibility gene for two hamartoma syndromes: Cowden disease (CD; MIM 158350) and Bannayan-Zonana (BZS) or Ruvalcaba-Riley-Smith syndrome (MIM 153480). Constitutive DNA from 37 CD families and seven BZS families was screened for germline PTEN mutations. PTEN mutations were identified in 30 of 37 (81%) CD families, including missense and nonsense point mutations, deletions, insertions, a deletion/insertion and splice site mutations. These mutations were scattered over the entire length of PTEN , with the exception of the first, fourth and last exons. A 'hot spot' for PTEN mutation in CD was identified in exon 5 that contains the PTPase core motif, with 13 of 30 (43%) CD mutations identified in this exon. Seven of 30 (23%) were within the core motif, the majority (five of seven) of which were missense mutations, possibly pointing to the functional significance of this region. Germline PTEN mutations were identified in four of seven (57%) BZS families studied. Interestingly, none of these mutations was observed in the PTPase core motif. It is also worthy of note that a single nonsense point mutation, R233X, was observed in the germline DNA from two unrelated CD families and one BZS family. Genotype-phenotype studies were not performed on this small group of BZS families. However, genotype-phenotype analysis inthe group of CD families revealed two possible associations worthy of follow-up in independent analyses. The first was an association noted in the group of CD families with breast disease. A correlation was observed between the presence/absence of a PTEN mutation and the type of breast involvement (unaffected versus benign versus malignant). Specifically and more directly, an association was also observed between the presence of a PTEN mutation and malignant breast disease. Secondly, there appeared to be an interdependent association between mutations upstream and within the PTPase core motif, the core motif containing the majority of missense mutations, and the involvement of all major organ systems (central nervous system, thyroid, breast, skin and gastrointestinal tract). However, these observations would need to be confirmed by studying a larger number of CD families.   相似文献   
6.
Respond on comments on Lieberman's article: Cyclosiloxanes Produce Fatal Liver and Lung Damage in Mice. Environ Health Perspect 107:161-165  相似文献   
7.
PURPOSE: The purpose is to investigate whether aggressive basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) differ from nonaggressive BCC and SCC with respect to the p53 mutation spectrum and whether specific mutations can serve as prognostic indicators of tumor aggressiveness. EXPERIMENTAL DESIGN: We analyzed 342 tissues from patients with aggressive and nonaggressive BCCs and SCCs for p53 mutations by single-strand conformation polymorphism and nucleotide sequencing. RESULTS: p53 mutations were detected in 33 of 50 aggressive BCCs (66%), 37 of 98 nonaggressive BCCs (38%), 28 of 80 aggressive SCCs (35%), 28 of 56 nonaggressive SCCs (50%), and 3 of 29 samples of sun-exposed skin (10%). About 71% of the p53 mutations detected in aggressive and nonaggressive BCCs and SCCs were UV signature mutations. The frequency of CC to TT mutations in aggressive (36%) and nonaggressive SCCs (39%) was 2-fold higher than in aggressive (18%) and nonaggressive (14%) BCCs. In contrast, aggressive BCCs had a higher frequency (24%) of transversions than nonaggressive BCCs (8%) and aggressive (14%) and nonaggressive (11%) SCCs did. CONCLUSIONS: Our results indicate that UV radiation is responsible for the induction of p53 mutations and perhaps for the initiation of both aggressive and nonaggressive BCCs and SCCs. Although some differences in p53 mutation frequency, types of mutation, and hot spots were seen between aggressive and nonaggressive BCCs and SCCs, these factors do not constitute as clear-cut diagnostic or prognostic indicators of tumor aggressiveness. Tumor aggressiveness may be attributable to other genetic changes or events that occur during tumor progression.  相似文献   
8.
The effect of changes in the external concentrations (0.4-10 mM) of Ca2+ ions on AMPA receptors (AMPARs) of different subunit composition was studied on freshly isolated rat brain neurones. Ca2+ produces rapid and reversible voltage-independent inhibition of AMPARs. Ca2+-permeable and Ca2+-impermeable AMPARs are equally sensitive to external Ca2+ suggesting that the effect is not addressed to the ion channel. The inhibition of responses evoked by AMPA is significantly larger than those evoked by kainate or glutamate. Cyclothiazide and aniracetam, which are known to prevent AMPAR desensitization, both greatly diminish inhibition of AMPARs by Ca2+. Cyclothiazide is more potent than aniracetam in both preventing of AMPAR desensitization and protecting against the Ca2+ inhibitory effect on hippocampal pyramidal cells. On giant cholinergic interneurones of striatum, aniracetam but not cyclothiazide significantly prevents inhibition by Ca2+. This agrees with available data on relative abundance of flip and flop splice variants in these cell types. The results suggest that Ca2+ may allosterically increase AMPA receptor desensitization independently on subunit composition and splice variants.  相似文献   
9.
We studied the long-term effects of neonatal pro-inflammatory stress (NPS) on the expression of corticoliberin and its receptors in the dorsal and ventral hippocampus of juvenile male and female rats. In the dorsal hippocampus of juvenile males, NPS increases the expression of corticoliberin mRNA. This effect is absent in females, where we found a tendency to an increase in the expression of CRHR2 receptor mRNA in the ventral hippocampus. Thus, NPS induces long-term changes in the expression of genes associated with stress, specifically in different parts of the hippocampus; these changes may be related the mechanism of “early programming” of the predisposition to depression and to the gender-related specificity of disease pathogenesis.  相似文献   
10.

Aims:

To examine the variation in risk factors and hospitalization costs among four elderly dementia cohorts by race and gender.

Materials and Methods:

The 2008 Tennessee Hospital Discharged database was examined. The prevalence, risk factors and cost of inpatient care of dementia were examined for individuals aged 65 years and above, across the four race gender cohorts - white males (WM), black males (BM), white females (WF), and black females (BF).

Results:

3.6% of patients hospitalized in 2008 had dementia. Dementia was higher among females than males, and higher among blacks than whites. Further, BF had higher prevalence of dementia than WF; similarly, BM had a higher prevalence of dementia than WM. Overall, six risk factors were associated with dementia for the entire sample including HTN, DM, CKD, CHF, COPD, and stroke. These risk factors varied slightly in predicting dementia by race and gender. Hospital costs were 14% higher among dementia patients compared to non-dementia patients.

Conclusions:

There exist significant race and gender disparities in prevalence of dementia. A greater degree of co-morbidity, increased duration of hospital stay, and more frequent hospitalizations, may result in a higher cost of inpatient dementia care. Aggressive management of risk factors may subsequently reduce stroke and cost of dementia care, especially in the black population. Race and gender dependent milestones for management of these risk factors should be considered.  相似文献   
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