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51.
Background and Purpose: Uncertainty persists over the effects of blood pressure-lowering treatment in acute intracerebral hemorrhage (ICH). We assessed the effects of treatment with candesartan in acute ICH and according to different types of hematoma. Methods: Post-hoc analysis of the Scandinavian Candesartan Acute Stroke Trial, a randomized- and placebo-controlled, double-masked trial of candesartan in patients with any stroke within the acute phase (<30 hours) and high systolic blood pressure (≥140 mm Hg). We collected baseline computed tomography scans of participants with ICH, and characterized hematoma volume (planimetric approach), location (deep versus lobar or infratentorial), hemisphere side, and presence of intraventricular hemorrhage. The trial's 2 coprimary effect variables were the composite endpoint of vascular death, stroke or myocardial infarction, and functional outcome at 6 months according to the modified Rankin scale. We used Cox, ordinal, and binary logistic regression for analysis and adjusted for key, predefined prognostic variables. Results: Of 274 participants with ICH, computed tomography scans were available in 205 patients (74.8%). There were no significant differences between the candesartan and placebo groups with respect to hematoma volume (median 15.6 mL versus 13.5 mL, P = .96), deep location (77% versus 72%, P = .64), right hemisphere (49% versus 51%, P = .46), and presence of intraventricular hemorrhage (18% versus 11%, P = .22). Candesartan was associated with a significant increase in poor functional outcome in patients with deep hematoma (adjusted common odds ratio 2.27, 95% confidence interval 1.23-4.18, P = .009, P for interaction .015), but there was no differential effect on functional outcome or vascular events in any of the other imaging subgroups. Conclusions: Candesartan was not associated with any beneficial effect when initiated in the acute phase of ICH, a possible adverse effect on functional outcome in patients with deep hematomas cannot be ruled out by this study alone.  相似文献   
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The Norwegian water column monitoring program investigates the biological effects of offshore oil and gas activities in Norwegian waters. In three separate surveys in 2006, 2008, and 2009, bioaccumulation and biomarker responses were measured in mussels (Mytilus edulis) and Atlantic cod (Gadus morhua) held in cages at known distances from the produced water (PW) discharge at the Ekofisk oil field. Identical monitoring studies performed in all three years have allowed the biological effects and bioaccumulation data to be compared, and in addition, enabled the potential environmental benefits of a PW treatment system (CTour), implemented in 2008, to be evaluated. The results of the 2009 survey showed that caged animals were exposed to low levels of PW components, with highest tissue concentrations in mussels located closest to the PW discharge. Mussels located approximately 1-2 km away demonstrated only background concentrations of target compounds. Concentrations of polycyclic aromatic hydrocarbons (PAH) and alkyl phenol (AP) metabolites in the bile of caged cod were elevated at stations 200-250 m from the discharge. There was also a signal of exposure relative to discharge for the biomarkers CYP1A in fish and micronuclei in mussels. All other fish and mussel biomarkers showed no significant exposure effects in 2009. The mussel bioaccumulation data in 2009 indicated a lower exposure to the PW effluent than seen previously in 2008 and 2006, resulting in an associated general improvement in the health of the caged mussels. This was due to the reduction in overall discharge of PW components (measured as oil in water) into the area in 2009 compared to previous years as a result of the improved PW treatment system.  相似文献   
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Orthotopic bladder cancer model in rats mimics human bladder cancer with respect to urothelial tumorigenesis and progression. Utilizing this model at pT1 (superficial stage), we analyze the tissue responses to hexyl 5-aminolevulinate-induced photodynamic therapy (HAL-PDT). In comparison to untreated rats, HAL-PDT causes little change in tumor-free rat bladder but induces inflammatory changes with increased lymphocytes and mononuclear cell infiltration in rat bladders with tumor. Immunohistochemistry reveals that HAL-PDT is without effect on proliferating cell nuclear antigen expression within the tumor and increases caspase-3 expression in both normal urothelium and the tumor. Transmission electron microscopy reveals severe mitochondrial damage, formations of apoptotic bodies, vacuoles, and lipofuscin bodies, but no microvillus-formed niches in HAL-PDT-treated bladder cancer rats. Bioinformatics analysis of the gene expression profile indicates an activation of T-cell receptor signaling pathway in bladder cancer rats without PDT. HAL-PDT increases the expression of CD3 and CD45RA in the tumor (determined by immunohistochemistry). We suggest that pathways of action of HAL-PDT may include, at least, activations of mitochondrial apoptosis and autophagy, breakdown of cancer stem cell niches, and importantly, enhancement of T-cell activation.  相似文献   
55.
Nakken S  Rødland EA  Hovig E 《Human mutation》2010,31(12):1316-1325
In selectively neutral regions of the human genome, nucleotide substitutions do not occur at random with respect to the local DNA sequence neighborhood. However, apart from the hypermutability of methylated CpG dinucleotides, which can explain the overrepresentation of nucleotide transitions in this context, the sequence-specific factors underlying point mutation bias remain largely to be determined, both in nature and in quantitative impact. One hypothesis suggests that the physical characteristics of a DNA context could have a modulating effect on its mutability, adjusting the impact of damage or the efficiency of repair. Here, we report a genome-wide computational test of this hypothesis, in which we utilize a constrained set of human non-CpG SNPs as the source of selectively neutral germline mutations. Interestingly, we observe that the quantitative context-dependencies of some substitution types display significant associations to measures of local structural topography and helix stability in DNA. Most prominently, we find that the local sequence bias of transition mutations is significantly associated with the sequence-dependent level of helix instability imposed by the potentially underlying DNA mismatches. The results of our work indicate the extent to which DNA physical properties could have shaped the recent point mutational spectrum in the human genome.  相似文献   
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Background

BRCA2 c.68-7T>A has been demonstrated to cause aberrant splicing and is possibly pathogenic. The population prevalence of the variant is 0.2%, which higher than usual for pathogenic BRCA2 variants. The pathogenicity of the variant is discussed.

Methods

The outpatient genetic clinic at The Norwegian Radium Hospital, part of Oslo University Hospital, has invited breast cancer kindreds for genetic examinations and prospective follow-up of high risk patients since 1988. We have complete files of all activities and results, and we examined the files for association between BRCA2 c.68-7T>A and breast cancer.

Results

Seventeen out of 714 (2.4%) breast cancer kindreds sequenced for BRCA2 carried the variant BRCA2 c.68-7T>A (p?<?0.0001 compared to population controls). Segregation analysis was inconclusive (likelihood ratio 0.36) for pathogenicity. Two breast cancers were prospectively observed during 134 observation years (annual incidence rate 1.5% (95% CI 0.15% to 5.4%) and one additional breast cancer was diagnosed at first (prevalence) round.

Conclusion

BRCA2 c.68-7T>A is associated with breast cancer. In the families selected due to aggregation of breast cancer, carriers of the BRCA2 c.68-7T>A variant have increased risk for breast cancer. It is, however, possible that the variant has lower penetrance than the average pathogenic BRCA2 variants, and that in the families selected for having known aggregation of breast cancer other (modifying) factors contributed to the observed results.
  相似文献   
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In colorectal cancer, the relation between duration of symptoms and stage at presentation and prognosis is not yet settled. All 1263 patients treated for colorectal cancer at Levanger Hospital, 1980–2004, and 2892 patients treated in Norway during 2004 were included. The association between symptom duration as an explanatory variable and tumour stage as a dependent variable was analysed using a proportional odds logistic regression model. Known duration of symptoms was divided into four categories: <1 week, 1–8 weeks, 2–6 months and >6 months. There was an inverse relationship between symptom duration and colon cancer TNM-stage, OR = 0.73 (95% CI 0.63–0.84), p < 0.001 (Levanger Hospital) and 0.84 (0.75–0.95), p = 0.004 (Norway 2004), where the OR is per category of symptom duration. Duration of symptoms were also inversely associated with T-stage, N-stage and M-stage in colon cancer. These relationships were not found for rectal cancer. In colon cancer the relative five-year survival for the four intervals of symptom duration was 44%, 39%, 54% and 66%, p < 0.001, in Levanger, 1980–2004, and four-year survival was 46%, 62%, 75% and 74%, p < 0.001, in Norway 2004, respectively. For rectal cancer survival was not dependent on symptom duration. In a multivariate analysis of relative survival of patients with colon cancer, duration of symptoms was associated with survival independent of tumour differentiation and TNM-stage. Increasing duration of symptoms was positively associated with less advanced disease and better survival in colon cancer, but not in rectal cancer.  相似文献   
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