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101.
102.
Polychlorinated biphenyls (PCBs) are a group of environmental contaminants widely reported to cause gonadal toxicity in both humans and animals. This study investigated the amelioratory role of quercetin in PCBs‐induced DNA damage in male Wistar rats. Polychlorinated biphenyls were administered intraperitoneally at a dose of 2 mg kg?1 alone or in combination with quercetin (orally) at 50 mg kg?1 for 25 days. Quercetin modulation of PCBs‐induced gonadal toxicity was evaluated using selected oxidative stress indices, comet assay, measurement of DNA concentration and histology of the testes. Administration of PCBs alone caused a significant (P < 0.05) depletion in the total thiol level in testes of treated rats. Conversely, the levels of reactive oxygen species (ROS) and thiobarbituric acid reactive substances (TBARS) production were markedly elevated in testes of PCBs‐treated rats compared with control. Further, PCBs exposure produced statistically significant increases in DNA tail migration, degraded double‐stranded DNA (dsDNA) concentration and histological alterations of testes of the treated rats compared to control. Quercetin cotreatment significantly improved the testicular antioxidant status, decreased DNA fragmentation and restored the testicular histology, thus demonstrating the protective effect of quercetin in PCBs‐treated rats.  相似文献   
103.

Objective

The authors sought to evaluate the diagnostic accuracy of high-resolution computed tomography (HRCT) in the detection of pulmonary veno-occlusive disease (PVOD) in patients with pre-capillary pulmonary arterial hypertension (PAH) of unknown aetiology, and to identify the role of CT in diagnosis and therapy.

Materials and methods

The CT scans of 96 patients were retrospectively reviewed and assessed for specific HRCT findings: ground-glass opacities, septal lines and mediastinal lymph nodal enlargement (short diameter ≥1 cm). According to the HRCT findings, patients were divided into PVOD-suspicious and not PVOD-suspicious. Subsequently, a clinical-instrumental evaluation was performed, and the response to therapy and histopathological reports were evaluated.

Results

Radiological evaluation based on HRCT findings revealed 29 patients as PVOD-suspicious and 67 as not PVOD-suspicious. The final diagnosis was PVOD in 22 patients and idiopathic PAH in 74 patients. The CT scan showed 95.5 % sensitivity, 89 % specificity, 72.5 % positive predictive value, and 98.5 % negative predictive value, with a diagnostic accuracy of 90.5 % in identifying patients with PVOD.

Conclusions

Chest CT can be considered a screening test in the assessment of patients with PAH of unknown aetiology, and the radiologist can help the clinician to identify patients with CT findings that make PVOD highly probable.  相似文献   
104.
105.
Epidermal growth factor receptor (EGFR) is a trans-membrane tyrosine kinase taking part in cell transformation and tumor progression. One of the downstream pathways controlled by EGFR involves the mammalian target of rapamycin (mTOR), a proto-oncogene activated in several cell functions. Recent evidence seems to confirm that both EGFR and mTOR regulate angiogenesis. The aim of this study was to investigate the expression of EGFR and mTOR in laryngeal squamous cell carcinoma (LSCC) cells in a retrospective clinical setting and their correlation with tumor neo-angiogenesis, judged on the grounds of CD105-assessed microvascular density (MVD), and prognosis. We considered 76 consecutive patients with LSCC treated with surgery alone. Immunohistochemical expressions of EGFR, mTOR, and CD105 were measured using image analysis and findings underwent statistical analysis using univariate and multivariate models. We found that nodal status correlated significantly with patient prognosis in terms of disease-free survival (DFS) (p = 0.01). There was a strong direct correlation between mTOR and EGFR expression (p = 0.0003), and between mTOR and CD105-assessed MVD (p = 0.0025). Patients with a CD105-assessed MVD >5.28 % had a significantly higher recurrence rate (RR) (p = 0.026), and a significantly shorter DFS (p = 0.025). On multivariate analysis, only N stage [hazard ratio (HR) 3.54, p = 0.009] and CD105-assessed MVD (HR 2.87, p = 0.027) maintained their independent prognostic significance in terms of DFS. Judging from our promising findings, the EGFR-mTOR pathway should be investigated further to understand its role in LSCC neo-angiogenesis.  相似文献   
106.
Randomized clinical trial (RCT) is the best study design for treatment-related issues, yet these studies may present a number of biases and limitations. The objective of this study is to carry out a qualitative analysis of RCT methodology in the treatment of bipolar depression (BD). A systematic review covering the last 20 years was performed on PubMed selecting double-blind RCTs for BD. The identification items of the articles, their design, methodology, outcome and grant-related issues were all analyzed. Thirty articles were included, all of which had been published in journals with an impact factor >3. While almost half studies (46.7%) used less than 50 patients as a sample, 70% did not describe or did not perform sample size calculation. The Last Observation Carried Forward (LOCF) method was used in 2/3 of the articles and 53.4% of the studies had high sample losses (>20%). Almost half the items were sponsored by the pharmaceutical industry and 33.3% were sponsored by institutions or research foundations. Articles on the pharmacological treatment of BD have several limitations which hinder the extrapolation of the data to clinical practice. Methodological errors and biases are common and statistical simplifications compromise the consistency of the findings.  相似文献   
107.
Objective  To compare urinary placental growth factor (PlGF) concentration at 11+0 to 13+6 weeks of gestation in women who subsequently develop pre-eclampsia with normotensive controls.
Design  Nested case–control study within a prospective study for first trimester prediction of pre-eclampsia.
Setting  Routine antenatal visit in a teaching hospital.
Population  Fifty-two women who developed pre-eclampsia and 52 controls matched for gestational age and sample storage time.
Methods  Urinary PlGF concentration and PlGF to creatinine ratio were measured in women who developed pre-eclampsia and their matched controls. Comparisons between groups were performed using Student's t test.
Main outcome measures  Development of pre-eclampsia.
Results  In the pre-eclampsia group, the median urinary PlGF concentration (20.6 pg/ml, interquartile range [IQR] 9.1–32.0 pg/ml) and median urinary PlGF to creatinine ratio (1.6 pg/mg, IQR 1.2–2.5 pg/mg) were not significantly different from the control group (11.8 pg/ml, IQR 5.5–29.8 pg/ml, P = 0.1 and 1.7 pg/mg, IQR 1.2–2.3 pg/mg, P = 0.3, respectively). There were no significant differences between women with early-onset pre-eclampsia requiring delivery before 34 weeks ( n = 13) and those with late-onset pre-eclampsia ( n = 39) and between women with pre-eclampsia and fetal growth restriction (FGR) ( n = 25) and those with pre-eclampsia and no FGR ( n = 27) in either median PlGF concentration or median urinary PlGF to creatinine ratio.
Conclusions  The development of pre-eclampsia is not preceded by altered urinary PlGF concentration in the first trimester of pregnancy.  相似文献   
108.

OBJECTIVE

To determine if baseline subgroups in the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial can be identified for whom intensive compared with standard glycemia treatment had different effects on all-cause mortality.

RESEARCH DESIGN AND METHODS

Exploratory post hoc intention-to-treat comparisons were made between intensive and standard glycemia groups on all-cause mortality by subgroups defined by baseline characteristics.

RESULTS

There were few significant interactions between baseline characteristics and effects of intensive versus standard glycemia treatment on mortality: self-reported history of neuropathy (hazard ratio [HR] 1.95, 95% CI 1.41–2.69) versus no history of neuropathy (0.99, 0.79–1.26; P value for interaction 0.0008), higher A1C (A1C >8.5%: HR 1.64, 95% CI 1.22–2.22; A1C 7.5–8.4%: 1.00, 0.75–1.34; A1C <7.5%: 1.00, 0.67–1.50; P value for interaction 0.04), and aspirin use (HR 1.45, 95% CI 1.13–1.85, compared with 0.96, 0.72–1.27, in nonusers; P value for interaction 0.03).

CONCLUSIONS

We found a remarkable similarity of effect from intensive compared with standard glycemia treatment on mortality across most baseline subgroups. No differential effect was found in subgroups defined by variables anticipated to have an interaction: age, duration of diabetes, and previous history of cardiovascular disease. The three baseline characteristics that defined subgroups for which there was a differential effect on mortality may help identify patients with type 2 diabetes at higher risk of mortality from intensive regimens for glycemic control. Further research is warranted.Numerous epidemiological studies have demonstrated a relationship between elevated A1C and a greater risk of cardiovascular (CVD) events and mortality in type 2 diabetes (13). Therefore, it has been hypothesized that a reduction to near-normal levels of A1C in patients with type 2 diabetes would reduce the risk of these adverse outcomes. Three large randomized controlled clinical trials testing this hypothesis in individuals with longstanding type 2 diabetes reported their main results in the past 2 years (46).The Data Safety Monitoring Board of the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial discontinued the intensive glycemia arm because of an increase in all-cause mortality in the intensive glycemia arm compared with the standard glycemia arm. The finding of excess mortality in the intensive arm of the ACCORD trial has led to controversy about implementation of intensive glucose control in patients with type 2 diabetes (7,8). Adding to the controversy were results of the Action in Diabetes and Vascular Disease: Preterax and Diamicron MR Controlled Evaluation (ADVANCE) and Veterans Affairs Diabetes Trial (VADT), demonstrating that although there was no significant reduction in the primary end point of CVD events, there was no increase in mortality with the intensive glycemia arm compared with the standard glycemia arm (4,6), which has raised questions about reasons for these discrepancies (912).A critical question relates to the applicability and generalizability of the conclusions of the ACCORD trial to the broader population or to specific subgroups of patients with type 2 diabetes. Indeed, prespecified subgroup analyses in ACCORD did suggest a significant benefit of intensive glycemic control on CVD events in those participants with lower A1C at entry or absence of CVD event by history, but there was no suggestion of a differential effect on mortality (5). However, these observations are based on only a few subgroup analyses at the time of the primary publication. The effect on mortality of intensive compared with standard glycemia treatment may have been modified by other possible characteristics of patients at entry. We have therefore carried out exploratory post hoc analyses of the effects of intensive compared with standard glycemia treatment in ACCORD participants categorized by various baseline characteristics on all-cause mortality at the time of discontinuation of the intensive glycemia treatment of ACCORD, with the goal to determine if particular subgroups at higher or lower risk from the intensive intervention can be identified.  相似文献   
109.
Plasma P-selectin is increased in thrombotic consumptive platelet disorders   总被引:19,自引:4,他引:19  
P-selectin is a 140-kD protein found in the alpha-granules of platelets and the Weibel-Palade bodies of endothelial cells that on cell activation is expressed on the cell surface and also secreted into the plasma. The secreted form of P-selectin, like plasma P-selectin, differed from platelet membrane P-selectin in that its molecular mass was approximately 3 kD lower under reducing conditions. Both the secreted and plasma forms of P-selectin contained cytoplasmic sequence as determined by Western blot analysis with an affinity-purified rabbit anti-P-selectin cytoplasmic peptide antibody. We have measured plasma P- selectin and beta-thromboglobulin (beta TG) concurrently in (1) patients with consumptive thrombotic disorders, including disseminated intravascular coagulation (DIC), heparin-induced thrombocytopenia (HIT), and thrombotic thrombocytopenic purpura (TTP)/haemolytic uremic syndrome (HUS); (2) patients with idiopathic thrombocytopenic purpura (ITP); and (3) healthy controls. Patients with DIC, HIT, and TTP/HUS, but not ITP, had significantly elevated plasma P-selectin and beta TG levels when compared with their age-matched healthy controls. The increased plasma P-selectin and beta TG in patients with thrombotic disorders were likely to be the result of in vivo platelet and endothelial cell damage or activation. We also found that avoidance of veno-occlusion and other tedious measures customarily taken during blood collection and sample preparation to prevent in vitro platelet activation did not affect plasma P-selectin assay results. In addition, plasma P-selectin levels were not influenced by the presence of renal failure or heparin administration. These results indicate that plasma P- selectin may be a useful new marker for thrombotic diseases.  相似文献   
110.
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