首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 250 毫秒
1.
Polymorphisms (A33512C, C21151T and PAT −/+) of the xeroderma pigmentosum group C (XPC) were shown to contribute to genetic susceptibility to cancer. However, association studies on these polymorphisms in cancer have shown conflicting results. Thus, we performed a meta-analysis. Overall, there was no significant association between 33512C (9,091 patients and 11,553 controls) and cancer risk. No significant association was found in stratification analysis by tumor sites and ethnicities except an elevated lung cancer risk under the recessive genetic model in all subjects [P = 0.04, odds ratio (OR) = 1.20, 95% confidence interval (CI) 1.00–1.45, P heterogeneity = 0.88]. There was no significant association between 21151T (5,227 patients and 5,959 controls) and cancer risk in all subjects but an increased cancer risk in Caucasians under the recessive genetic model (P = 0.006, OR = 1.45, 95% CI 1.11–1.90, P heterogeneity = 0.75) and homozygote comparison (P = 0.02, OR = 1.41, 95% CI 1.07–1.81, P heterogeneity = 0.41). It might be that 21151T increases bladder cancer risk under the recessive genetic model (P = 0.02, OR = 1.49, 95% CI 1.06–2.09, P heterogeneity = 0.47) and homozygote comparison (P = 0.02, OR = 1.49, 95% CI 1.05–2.11, P heterogeneity = 0.23). There was no significant association between PAT + (4,600 patients and 4,866 controls) and cancer risk in all subjects. An increased cancer risk in Caucasians was found under the recessive genetic model (P = 0.02, OR = 1.20, 95% CI 1.03–1.40, P heterogeneity = 0.37) and homozygote comparison (P = 0.008, OR = 1.26, 95% CI 1.06–1.50, P heterogeneity = 0.13). The XPC PAT + allele might increase head and neck cancer risk (P = 0.02, OR = 1.29, 95% CI 1.04–1.59, P heterogeneity = 0.15). More studies based on larger, stratified, case–control population, especially studies investigate the combined effect of XPC A33512C, C21151T, and PAT, are required to further evaluate the role of these polymorphisms in different cancers.  相似文献   

2.
The cytochrome P450 1A1 gene (CYP1A1), encoding Phase I metabolic enzymes, appeared to be a candidate gene for breast cancer risk. However, studies on the association between polymorphisms in this gene and breast cancer have yielded conflicting results. We performed a meta-analysis to investigate the association with breast cancer of the CYP1A1 polymorphisms T3801C (9,316 cases and 12,714 controls) and A2455G (9,552 cases and 9,320 controls). In the genotype contrast of A2455G, both additive [GG vs AA, P = 0.04, fixed-effects OR 0.72; 95% CI (0.53–0.99), P = 0.95 for heterogeneity] and recessive [GG vs (GA + AA), P = 0.04, fixed-effects OR 0.73; 95% CI (0.53–0.99), P = 0.97 for heterogeneity] models produced significant results in east-Asians. In pre-menopausal women in a worldwide population, significant association between A2455G and breast cancer was also found using both models [additive model: P = 0.02, fixed-effects OR 0.52; 95% CI (0.29–0.92), P = 0.39 for heterogeneity; recessive model: P = 0.02, fixed-effects OR 0.51; 95% CI (0.29–0.90), P = 0.38 for heterogeneity]. Our meta-analysis suggests that an A2455G G/G genotype is associated with a trend of reduced breast cancer risk, both in east-Asian women and in pre-menopausal women worldwide, while the T3801C C allele might not be a risk factor for breast cancer. Larger scale primary studies are required to further evaluate the interaction of CYP1A1 polymorphisms and breast cancer risk in specific populations.  相似文献   

3.
Dyslipidemia and insulin resistance contribute to the endothelial cell dysfunction in hypertensive disorders of pregnancy (HDP) and increase the long-term risk of cardiovascular disease (CVD). The genes linking susceptibility to gestational hypertension (GH) and/or preeclampsia (PE) to the long-term risk of CVD are still unknown. We evaluated the potential association between 14 polymorphisms from six genes involved in lipid metabolism and insulin action and the risk of HDP: namely the lipoprotein lipase (LPL), hepatic lipase (LIPC), hormone sensitive lipase (LIPE), cholesteryl ester transfer protein (CETP), ApoCIII and ApoE gene polymorphisms. Overall, 169 women with HDP [proteinuria (PE) and gestational hypertension without proteinuria (GH)] and 169 controls matched for age and year of delivery were genotyped. Homozygosity of the −514T allele of the −514C > T polymorphism (LIPC gene) decreased the risk of GH (OR = 0.17, CI95: 0.02–0.76), while there were more −60G carriers of the −60C > G LIPE gene polymorphism (OR = 3.51, CI95:1.02–12.10) among GH cases, but not in PE cases. The common ApoCIII two-locus −482CC/3238CC genotype was lower in women with GH compared with controls (OR = 0.53, CI95: 0.3–0.9). The combined frequency of at-risk genotypes was higher in cases of GH compared with controls [one at-risk genotype: OR = 3.38 (95% CI: 0.48–41.8); two or more at-risk genotypes: OR = 7.14 (95% CI: 1.21–92.3, P = 0.01)], suggesting a gene-dose effect. We conclude that the combined effect of LIPC, LIPE and ApoCIII gene polymorphisms may increase the likelihood of GH, but seemingly not of PE.  相似文献   

4.
Diet is an important environmental factor interacting with our genes to modulate the likelihood of developing lipid disorders and, consequently, cardiovascular disease risk. Our objective was to study whether dietary intake modulates the association between APOA5 gene variation and body weight in a large population-based study. Specifically, we have examined the interaction between the APOA5-1131T>C and 56C>G (S19W) polymorphisms and the macronutrient intake (total fat, carbohydrate, and protein) in their relation to the body mass index (BMI) and obesity risk in 1,073 men and 1,207 women participating in the Framingham Offspring Study. We found a consistent and statistically significant interaction between the -1131T>C single-nucleotide polymorphism (SNP; but not the 56C>G) and total fat intake for BMI. This interaction was dose-dependent, and no statistically significant heterogeneity by gender was detected. In subjects homozygous for the -1131T major allele, BMI increased as total fat intake increased. Conversely, this increase was not present in carriers of the -1131C minor allele. Accordingly, we found significant interactions in determining obesity and overweight risks. APOA5-1131C minor allele carriers had a lower obesity risk (OR, 0.61, 95%; CI, 0.39-0.98; P = 0.032) and overweight risk (OR, 0.63, 95%; CI, 0.41-0.96; P = 0.031) compared with TT subjects in the high fat intake group (>or=30% of energy ) but not when fat intake was low (OR, 1.16, 95%; CI, 0.77-1.74; P = 0.47 and OR = 1.15, 95%; CI, 0.77-1.71; P = 0.48) for obesity and overweight, respectively). When specific fatty acid groups were analyzed, monounsaturated fatty acids showed the highest statistical significance for these interactions. In conclusion, the APOA5-1131T>C SNP, which is present in approximately 13% of this population, modulates the effect of fat intake on BMI and obesity risk in both men and women.  相似文献   

5.
Case-control studies investigating associations between multiple myeloma (MM) and the C677T and A1298C polymorphisms of the methylenetetrahydrofolate reductase (MTHFR) have provided controversial results. In an attempt to interpret these results, a meta-analysis of all available studies was performed. In the meta-analysis the pooled odds ratios (OR) were estimated using fixed effects (FE) and random effects (RE) models. The heterogeneity between studies, the sources of potential bias and the consistency of genetic effects across ethnicities were explored. Cumulative meta-analysis was also performed. The meta-analysis revealed non-significant heterogeneity between studies (Pq > or = 0.65). The dominant model for the effect of 677T allele produced significant association overall [FE OR = 1.23 (1.04-1.47)] and in Caucasians [FE OR = 1.54 (1.14-2.08)], but not in East Asians [FE OR = 1.05 (0.82-1.34)]. Although the cumulative meta-analysis for the dominant model of 677T allele showed a downward trend of RE OR for the period 2000-2007, the association still remained significant. Analysis of the A1298C polymorphisms revealed lack of association both in Caucasians and in East Asians. There is an indication of potential bias: a differential magnitude of effect in large versus small studies emerged. In conclusion, the accumulated evidence indicated an association between MTHFR C677T polymorphism and MM in Caucasians under a dominant model.  相似文献   

6.

Purpose

The purpose of this study was to investigate the impact of malignancy and chemotherapy on the clinical and microbiological characteristics of Clostridium difficile infections (CDI).

Methods

CDI patients with a history of malignancy within 5 years were defined as the cancer group. The characteristics of the patients were compared according to the presence of malignancy.

Results

Of 580 patients with CDI, 159 (27.4 %) belonged to the cancer group and 421 (72.6 %) to the non-cancer group. More of the patients in the cancer group than those in the non-cancer group had been hospitalized within the prior 2 months (P?<?0.001). Leukocytosis was more common in the non-cancer group (P?=?0.034), while infection by PCR ribotype 017 strains was more common in the cancer group, with marginal significance (P?=?0.07). Recurrence was more frequent in the cancer group (20.4 % vs. 9.5 %, P =0.005) and cancer was an independent risk factor for recurrence of CDI (OR?=?2.66, 95 % CI 1.34-5.29, P =0.005). Age also contributed to the recurrence of CDI (OR?=?1.03, 95 % CI 1.00-1.06, P =0.026).

Conclusions

Malignancy and age are independent risk factors for recurrence of CDI. Cancer patients require careful observation for recurrence after treatment of CDI.
  相似文献   

7.
Li X  Huang Y  Fu X  Chen C  Zhang D  Yan L  Xie Y  Mao Y  Li Y 《Mutagenesis》2011,26(3):371-383
The steroid-5-alpha-reductase, alpha polypeptide 2 (SRD5A2) gene plays a crucial role in androgen metabolism pathway in human prostate. It encodes SRD5A2 enzyme, which catalyses testosterone to dihydrotestosterone (DHT). DHT is the main active structure binding with androgen receptor (AR). After the activation of AR, it further regulates a series of target genes in androgen metabolism pathway. However, no clear consensus has been reached on the association between the SRD5A2 V89L, A49T and TA repeat polymorphisms and prostate cancer (PCa) risk. Thus, we performed a meta-analysis of 31 association studies with 14,726 PCa cases and 15,802 controls. We found no association between PCa and 89L compared with 89V allele [odds ratio (OR) = 1.02, 95% confidence interval (CI) 0.98-1.06, P(heterogeneity) = 0.44]. The 49T allele showed a significantly elevated effect on the high stage (Stages III-IV) of PCa risk both under the dominant genetic model (OR = 2.13, 95% CI 1.44-3.15, P(heterogeneity) = 0.65) and in the contrast T versus A allele (OR = 2.06, 95% CI 1.41-3.02, P(heterogeneity) = 0.69). There was a significantly decreased association between PCa and long TA repeat as compared versus short TA repeat (OR = 0.86, 95% CI 0.74-1.00, P(heterogeneity) = 0.79). No significant between-study heterogeneity was found in all subjects under four genetic models (dominant model, recessive model, allele comparison and homozygosity comparison) for these three polymorphisms, respectively, so the fixed effects model was used to pool the result. Our result indicated that carriers of 49T might improve the risk of PCa in higher stages (Stages III-IV), carriers of long TA repeat might decrease the risk of PCa and 89L may not be an important risk factor for PCa. However, due to the limited sample sizes, this meta-analysis did not achieve sufficiently conclusive results. Still more well-designed studies should be performed to clarify the role of these three polymorphisms in the development of PCa.  相似文献   

8.
Exertional rhabdomyolysis is a complex and poorly understood entity. The inflammatory system has an important role in muscle injury and repair. Serum creatine kinase (CK) is often used as systemic biomarker representing muscle damage. Considerable variation exists in CK response between different subjects. Genetic elements may act as predisposition factors for exertional srhabdomyolysis. Based on their biological activity, we hypothesized that in healthy subjects IL6 G-174C and TNFA G-308A promoter polymorphisms would be associated with CK response to exercise. We determined serum CK activity pre- and post-maximal eccentric contractions of the elbow flexor muscles. IL6 G-174C and TNFA G-308A genotypes were analyzed for possible relationship with changes in serum CK activity. IL6 G-174C genotype was associated with CK activity in a Dose-Dependent fashion. Subjects with one or more of the -174C allele had a greater increase and higher peak CK values than subjects homozygous for the G allele (mean +/- SE U/L: GG, 2,604 +/- 821; GC, 7,592 +/- 1,111; CC, 8,403 +/- 3,849, ANOVA P = 0.0003 for GG + GC genotypes versus CC genotype, P = 0.0005 for linear trend). IL6-174CC genotype was associated with a greater than threefold increased risk of massive CK response (adjusted odds ratio 3.29, 95% confidence interval 1.27-7.85, P = 0.009). A milder association (P = 0.06) was noted between TNFA G-308A genotype and CK activity. In conclusion, we found a strong association of the IL6 G-174C genotype with systemic CK response to strenuous exercise. Data suggest that homozygosity for the IL6-174C allele is a clinically important risk factor for exercise-induced muscle injury, further supporting the central role of cytokines in the reactive inflammatory process of muscle damage and repair.  相似文献   

9.
ERCC1 (excision repair cross complementation group 1) is a subunit of the nucleotide excision repair complex, which can perform DNA strand incision correction of DNA damage. Association studies on the ERCC1 polymorphisms (C8092A and T19007C) in cancer had shown conflicting results. We performed a meta-analysis from all eligible case-control studies to assess the purported associations. Overall, the 19007C allele (3 853 patients and 4 349 controls) showed no significant effect on cancer risk compared to 19007T allele (P=0.39, odds ratio (OR)=0.95; 95% confidence interval (CI) 0.85-1.06, P(heterogeneity)=0.001) in all subjects. Meta-analysis under other genetic contrasts did not reveal any significant association of T19007C to cancer in all subjects, Caucasians and Asians. The 19007C allele (2 279 patients and 2 808 controls) showed no significant effect on lung cancer risk compared to 19007T allele (P=0.72, OR=0.94, 95% CI 0.69-1.29, P(heterogeneity)=0.0001) in all subjects. No significant effect of 8092A allele (3 865 patients and 3 750 controls) on cancer risk in all subjects (P=0.85, OR=1.01, 95% CI 0.94-1.08, P(heterogeneity)=0.92) and in Caucasians and Asians compare to 8092C. No evidences of association of C8092A (501 patients and 620 controls) to squamous cell carcinoma were found. The accumulated evidence indicated ERCC1 T19007C and C8092A might not be risk factors for cancer. Significant between-study heterogeneity existed in T19007C, which arose from a study showing significant protecting effect of 19007C allele compare to 19007T allele in smokers. More studies based on larger, stratified case-control population should be required to further evaluate the role of ERCC1 C8092A and T19007C polymorphisms in different cancer, especially in smokers.  相似文献   

10.
Carrying the cytosine-adenosine (CA)19 repeat polymorphism in insulin-like growth factor-1 (IGF1) is associated with lower serum proteins and decreased prostate cancer risk. Carrying the -202A/C genotype in insulin-like growth factor binding protein-3 (IGFBP3) also has been associated with lower serum levels of the binding protein. However, the association between this variant and prostate cancer is inconsistent. To test the hypothesis that inconsistencies are partly due to cancer grade-specific differences in strength and direction of associations, we reanalyzed data from our previous Durham Veterans Administration Hospital study of blacks and whites comprising 47 cases (19 African Americans) with Gleason sum > or = 7, 50 cases (30 African Americans) with Gleason sum < 7 and 93 controls (49 African Americans). Compared to controls, the association between carrying the IGFBP3 C allele and prostate cancer risk was in OR(Low-Gleason) = 4.0; 95% CI: 1.4-12.3 compared to OR(High-Gleason) = 1.0; 95% CI: 0.4-2.2. Association patterns were similar in African Americans (OR(Low-Gleason) = 3.6; 95% CI: 1.0-13.2 vs. OR(High-Gleason) = 1.4; 95% CI: 0.4-2.3) and whites (OR(Low-Gleason) = 5.6; 95% CI: 0.6-49.0 vs. OR(High-Gleason) = 0.6; 95% CI: 0.2-2.2). The inverse association between carrying the IGF1 (CA)19 repeat variant did not vary by grade or ethnicity. If confirmed in larger studies, these findings support the hypothesis that the association between IGFBP3 C allele and prostate cancer is grade specific in both ethnic groups.  相似文献   

11.
This study was aimed to determine the risk factors of Carbapenem-resistant Enterobacteriaceae (CRE) nosocomial infections and assess the clinical outcomes. A case-case–control design was used to compare two groups of case patients with control patients from March 2010 to November 2014 in China. Risk factors for the acquisition of CRE infections and clinical outcomes were analyzed by univariable and multivariable analysis. A total of 94 patients with CRE infections, 93 patients with Carbapenem-susceptible Enterobacteriaceae (CSE) infections, and 93 patients with organisms other than Enterobacteriaceae infections were enrolled in this study. Fifty-five isolates were detected as the carbapenemase gene. KPC-2 was the most common carbapenemase (65.5 %, 36/55), followed by NDM-1 (16.4 %, 9/55), IMP-4 (14.5 %, 8/55), NDM-5 (1.8 %, 1/55), and NDM-7 (1.8 %, 1/55). Multivariable analysis implicated previous use of third or fourth generation cephalosporins (odds ratio [OR], 4.557; 95 % confidence interval [CI], 1.971–10.539; P?<?0.001) and carbapenems (OR, 4.058; 95 % CI, 1.753-9.397; P?=?0.001) as independent risk factors associated with CRE infection. The in-hospital mortality of the CRE group was 57.4 %. In the population of CRE infection, presence of central venous catheters (OR, 4.464; 95 % CI, 1.332–14.925; P?=?0.015) and receipt of immunosuppressors (OR, 7.246; 95 % CI, 1.217–43.478; P?=?0.030) were independent risk factors for mortality. Appropriate definitive treatment (OR, 0.339; 95 % CI, 0.120–0.954; P?=?0.040) was a protective factor for in-hospital death of CRE infection. Kaplan–Meier curves of the CRE group had the shortest survival time compared with the other two groups. Survival time of patients infected with Enterobacteriaceae with a high meropenem MIC (≥8 mg/L) was shorter than that of patients with a low meropenem MIC (2,4, and?≤?1 mg/L). In conclusion, CRE nosocomial infections are associated with prior exposure to third or fourth generation cephalosporins and carbapenems. Patients infected with CRE had poor outcome and high mortality, especially high meropenem MIC (≥8 mg/L). Appropriate definitive treatment to CRE infections in the patient is essential.  相似文献   

12.
13.
Oesophageal cancer-related gene (ECRG2) is a tumour suppressor gene and it has been suggested that a triplet TCA short tandem repeat (STR) in the noncoding region of exon 4 plays a role in genetic susceptibility to oesophageal cancer. In the present study, ECRG2 STR polymorphism was studied in 134 patients with oesophageal cancer and 194 controls, using PCR and polyacrylamide gel electrophoresis. The results showed a higher frequency of the ECRG2 TCA (3)/TCA (4) genotype in cancer patients than in controls (odds ratio 2.6, 95% CI 1.0-6.4, p = 0.03). The association of the ECRG2 TCA (3)/TCA (4) genotype with clinical characteristics showed an increased risk for squamous cell histology (2.8, 95% CI 1.1-7.1, p = 0.03), while no association with tumor location or lymph node involvement was observed. Interaction of tobacco, alcohol and occupational exposure with the ECRG2 genotypes did not show modulation of risk. In conclusion, the ECRG2 TCA (3)/TCA (4) genotype is associated with the risk of oesophageal carcinoma in a North Indian population.  相似文献   

14.
Published data on the association between E-cadherin (CDH1) -160 C/A polymorphism and prostate cancer (PCA) risk are inconclusive. To derive a more precise estimation of the relationship, a meta-analysis was performed. A logistic regression approach proposed for molecular association studies was used to estimate a biological model of the gene effect. A total of 11 studies including 2637 cases and 2673 controls were involved in this meta-analysis. Logistic regression analysis indicated that the CDH1 -160 C/A genotypes were associated with PCA risk. The genetic model test indicated that the genetic model was most likely to be dominant (CA+AA vs CC). Overall, meta-analysis indicated that the -160A allele carriers (CA+AA) had a 21% elevated risk of PCA, when compared with the homozygotes (CC) (odds ratio (OR)=1.21; 95% confidence interval (CI): 0.97-1.51; P=0.090, P(heterogeneity)=0.001). In the subgroup analyses by ethnicity, significantly elevated risks were associated with -160 variant genotypes (CA+AA) in both European and Asian populations (OR=1.24; 95% CI: 1.08-1.43; P=0.003, P(heterogeneity)=0.220 and OR=1.54; 95% CI: 1.23-1.93; P<0.001, P(heterogeneity)=0.200). However, no significant associations were found in Africans (OR=0.59; 95% CI: 0.32-1.09; P=0.090, P(heterogeneity)=0.070). Although some modest bias could not be eliminated, this meta-analysis suggests that the CDH1 -160A allele is a low-penetrant risk factor for developing PCA, especially in Europeans and Asians.  相似文献   

15.
Staphylococcus aureus might amplify symptoms in chronic inflammatory skin diseases. This study evaluates skin and mucosal colonization with S. aureus in patients with psoriasis, acne and rosacea. A systematic literature search was conducted. Both odds ratios (OR) for colonization in patients versus controls and the prevalence of colonization in patients are reported. Fifteen articles about psoriasis and 13 about acne (12 having a control group) were included. No study in rosacea met our inclusion criteria. For psoriasis, one study out of three controlled studies showed increased skin colonization (OR 18.86; 95 % confidence interval [CI] 2.20–161.99). Three out of the five studies that reported on nasal colonization showed significant ORs varying from 1.73 (95 % CI 1.16–2.58) to 14.64 (95 % CI 2.82–75.95). For acne one of the three studies that evaluated skin colonization reported a significant OR of 4.16 (95 % CI 1.74–9.94). A relation between nasal colonization and acne was not found. Limitations in study design and low sample sizes should be taken into consideration when interpreting the results. Colonisation with S. aureus seems to be increased in patients with psoriasis. This bacterial species, known for its potential to induce long-lasting inflammation, might be involved in psoriasis pathogenesis. Information on acne is limited. Prospective controlled studies should further investigate the role of S. aureus in chronic inflammatory skin diseases.  相似文献   

16.
The DNA double strand break repair gene TOPBP1 has been suggested as a breast cancer susceptibility gene and a missense variant Arg309Cys was observed at elevated frequency in familial breast cancer cases compared to healthy controls from Finland. We found the Arg309Cys allele at a 13% carrier frequency in a hospital-based series of 1064 German breast cancer patients and at a 14% carrier frequency in 1014 population controls (OR 0.89, 95%CI 0.69-1.15; p = 0.4). Arg309Cys carriers were not enriched among patients with a family history of breast cancer (OR = 0.87, 95%CI 0.53-1.43, p = 0.6) and were slightly underrepresented in patients with bilateral disease (OR = 0.49, 95%CI = 0.24-0.99; p = 0.047). In the latter group, the mean age at diagnosis was 62 years in carriers and 54 years in non-carriers (p = 0.004). We conclude that there is no evidence for the TOPBP1*Arg309Cys variant to confer an increased risk for breast cancer in the German population.  相似文献   

17.
The sequences of the mitochondrial genomes of the oomycetes Phytophthora ramorum and P. sojae were determined during the course of complete nuclear genome sequencing (Tyler et al., Science, 313:1261,2006). Both mitochondrial genomes are circular mapping, with sizes of 39,314 bp for P. ramorum and 42,977 bp for P. sojae. Each contains a total of 37 recognizable protein-encoding genes, 26 or 25 tRNAs (P. ramorum and P. sojae, respectively) specifying 19 amino acids, six more open reading frames (ORFs) that are conserved, presumably due to functional constraint, across Phytophthora species (P. sojae, P. ramorum, and P. infestans), six ORFs that are unique for P. sojae and one that is unique for P. ramorum. Non-coding regions comprise about 11.5 and 18.4% of the genomes of P. ramorum and P. sojae, respectively. Relative to P. sojae, there is an inverted repeat of 1,150 bp in P. ramorum that includes an unassigned unique ORF, a tRNA gene, and adjacent non-coding sequences, but otherwise the gene order in both species is identical. Comparisons of these genomes with published sequences of the P. infestans mitochondrial genome reveals a number of similarities, but the gene order in P. infestans differed in two adjacent locations due to inversions and specific regions of the genomes exhibited greater divergence than others. For example, the breakpoints for the inversions observed in P. infestans corresponded to regions of high sequence divergence in comparisons between P. ramorum and P. sojae and the location of a hypervariable microsatellite sequence (eight repeats of 24 bp) in the P. sojae genome corresponds to a site of major length variation in P. infestans. Although the overwhelming majority of each genome is conserved (81–92%), there are a number of genes that evolve more rapidly than others. Some of these rapidly evolving genes appear specific to Phytophthora, arose recently, and future evaluation of their function and the effects of their loss could prove fruitful for understanding the phylogeny of these devastating plant pathogens. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

18.
19.
Mitochondria play important roles in cellular energy production, free radical generation, and apoptosis. In a previous report, the mitochondrial DNA (mtDNA) G10398A (Thr-->Ala) polymorphism was associated with breast cancer risk in African-American women [Cancer Res 2005;65:8028-33]. We sought to replicate the association by genotyping the G10398A polymorphism in multiple established population-based case-control studies of breast cancer in African-American women. The 10398A allele was not significantly associated with risk in any of the studies: San Francisco (542 cases, 282 controls, odds ratio OR = 1.73, 95% confidence interval CI = 0.87-3.47, P = 0.12); Multiethnic Cohort (391 cases, 460 controls, OR = 1.08, 95% CI = 0.62-1.86, P = 0.79); and CARE and LIFE (524 cases, 236 controls, OR = 0.81, 95% CI = 0.43-1.52, P = 0.50). With data pooled across the studies (1,456 cases and 978 controls), no significant association was observed with the 10398A allele (OR = 1.14, 95% CI = 0.80-1.62, P = 0.47, test for heterogeneity = 0.30). In analysis of advanced breast cancer cases (n = 674), there was also no significant association (OR = 1.18, 95% CI = 0.76-1.82, P = 0.46). Our results do not support the hypothesis that the mtDNA G10398A polymorphism is, as has previously been reported, a marker of breast cancer risk in African Americans.  相似文献   

20.
The aim of the retrospective case-control study presented here was to elucidate the incidence, risk factors, and outcomes of nosocomial infections caused by quinolone-resistant Escherichia coli (QREC). During the 3-year period studied, 51 nosocomial QREC infections were found, and the characteristics of these cases were compared with those of 102 control patients with quinolone-susceptible nosocomial infections. In the multivariate analysis, risk factors were identified as prior quinolone therapy (odds ratio [OR], 18.49; 95% confidence interval [CI], 5.53–61.82; P value <0.001), urinary tract abnormalities (OR, 6.69; 95% CI, 1.68–26.63; P=0.007), and prior therapy with other antimicrobial agents (OR, 3.57; 95% CI, 1.38–9.27; P=0.009). No difference in mortality or in length of hospital stay was found. Prudent use of quinolones, especially in patients with urinary tract abnormalities, is probably the best way to avoid an increase in the incidence of QREC infections, but further studies on interventions with restricted use of quinolones are necessary to demonstrate the effectiveness and safety of this strategy.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号