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51.
The authors investigated the role of resveratrol (RV), a natural poliphenolic molecule with several biological activities, in transforming growth factor-β (TGF-β)-induced proliferation and differentiation of ex vivo human pulmonary fibroblasts into myofibroblasts. The effects of RV treatment were evaluated by analyzing TGF-β-induced α-smooth muscle actin (α-SMA) expression and collagen production, as well as cell proliferation of both normal and idiopathic pulmonary fibrosis (IPF) lung fibroblasts. Results demonstrate that RV inhibits TGF-β-induced cell proliferation of both normal and pathological lung fibroblasts, attenuates α-SMA expression at both the mRNA and protein levels, and also inhibits intracellular collagen deposition. In order to understand the molecular mechanisms, the authors also investigated the effects of RV treatment on signaling pathways involved in TGF-β-induced fibrosis. The authors show that RV inhibited TGF-β-induced phosphorylation of both extracellular signal-regulated kinases (ERK1/2) and the serine/threonine kinase, Akt. Moreover, RV treatment blocked the TGF-β-induced decrease in phosphatase and tensin homolog (PTEN) expression levels.  相似文献   
52.
53.
Normal cellular counterparts of B cell chronic lymphocytic leukemia   总被引:4,自引:0,他引:4  
In an attempt to compare B cell chronic lymphocytic leukemia (B-CLL) with its normal cellular counterpart, the cell surface phenotype of 100 cases of B-CLL was determined by using a panel of monoclonal antibodies (MoAbs) directed against B cell-restricted and -associated antigens. The majority of B-CLL cells expressed Ia, B4 (CD19), B1 (CD20), B2 (CD21), surface immunoglobulin (sIg), and T1 (CD5) but lacked C3b (CD35) receptors. In contrast, the overwhelming majority of small unstimulated B cells expressed Ia, B4, B1, B2, sIg, and C3b receptors but lacked detectable T1. Small numbers of weakly sIg+ cells could be identified in peripheral blood and tonsil that coexpressed the B1 and T1 antigens. Approximately 16% of fetal splenocytes coexpressed B1, T1, weak sIg, B2, and Ia but lacked C3b receptors and therefore closely resembled most B-CLL cells. With the phenotypic differences between the majority of small unstimulated B cells and B-CLL cells, we examined normal in vitro activated B cells and B-CLL cells for the expression of B cell-restricted and -associated activation antigens. Of 20 cases examined, virtually all expressed B5, and approximately 50% of the cases expressed interleukin-2 receptors (IL-2R) and Blast-1. Normal B cells were activated with either anti-Ig or 12-0-tetradecanoylphorbol- beta-acetate (TPA) and then were examined for coexpression of B1, T1, and the B cell activation antigens B5 and IL-2R. Only cells activated with TPA coexpressed B1 and T1 as well as B5 and IL-2R. B cells activated with either anti-Ig or TPA proliferated in the presence of IL- 2, whereas B-CLL cells did not, although they all expressed the identical 60-kilodalton proteins by immunoprecipitation. These studies are consistent with the notion that B-CLL resembles several minor subpopulations of normal B cells including a population of B cells that are activated in vitro directly through the protein kinase C pathway.  相似文献   
54.
Purpose

Patients with patent foramen ovale (PFO) and cryptogenic ischemic stroke (CS) are at risk for stroke recurrence. The optimal antithrombotic strategy in patients who undergo medical management is still debated.

Methods

We systematically searched the literature for studies that reported on cerebrovascular event recurrences and/or death in patients with PFO treated with oral anticoagulation (OAC) or antiplatelet therapy (APT) for secondary prevention of CS. The efficacy endpoints were stroke recurrence and the composite of stroke, transient ischemic attack or all-cause death. Major bleedings represented the safety endpoint.

Results

A total of 16 studies with 3953 patients (OAC?=?1527, APT?=?2426) were included. Weighted mean follow-up was 2.9 years. OAC was associated with a significant reduction in the risk of stroke compared with APT (RR 0.65; 95% CI 0.44–0.95; ARR 2%, NNT 49), while no difference was found regarding the composite outcome (RR 0.78; 95% CI 0.57–1.07) and the safety outcome (RR 1.57; 95% CI 0.85–2.90; p?=?0.15).

Conclusions

OAC was more effective than APT in reducing the risk of stroke recurrence in patients with PFO and CS, without a significant increase in the risk of major bleedings. Our findings support the need for further randomized data focused on the comparison of antithrombotic strategies in this setting.

  相似文献   
55.

Objectives

This study sought to assess whether transradial access (TRA) compared with transfemoral access (TFA) is associated with consistent outcomes in male and female patients with acute coronary syndrome undergoing invasive management.

Background

There are limited and contrasting data about sex disparities for the safety and efficacy of TRA versus TFA for coronary intervention.

Methods

In the MATRIX (Minimizing Adverse Haemorrhagic Events by TRansradial Access Site and Systemic Implementation of angioX) program, 8,404 patients were randomized to TRA or TFA. The 30-day coprimary outcomes were major adverse cardiovascular and cerebrovascular events (MACCE), defined as death, myocardial infarction, or stroke, and net adverse clinical events (NACE), defined as MACCE or major bleeding.

Results

Among 8,404 patients, 2,232 (26.6%) were women and 6,172 (73.4%) were men. MACCE and NACE were not significantly different between men and women after adjustment, but women had higher risk of access site bleeding (male vs. female rate ratio [RR]: 0.64; p = 0.0016), severe bleeding (RR: 0.17; p = 0.0012), and transfusion (RR: 0.56; p = 0.0089). When comparing radial versus femoral, there was no significant interaction for MACCE and NACE stratified by sex (pint = 0.15 and 0.18, respectively), although for both coprimary endpoints the benefit with TRA was relatively greater in women (RR: 0.73; p = 0.019; and RR: 0.73; p = 0.012, respectively). Similarly, there was no significant interaction between male and female patients for the individual endpoints of all-cause death (pint = 0.79), myocardial infarction (pint = 0.25), stroke (pint = 0.18), and Bleeding Academic Research Consortium type 3 or 5 (pint = 0.45).

Conclusions

Women showed a higher risk of severe bleeding and access site complications, and radial access was an effective method to reduce these complications as well as composite ischemic and ischemic or bleeding endpoints.  相似文献   
56.

Aims

The most recent European guidelines have proposed new definitions of pulmonary hypertension (PH) in left heart disease, to better approach the characteristics required to reflect the presence of pulmonary vascular disease. The purpose of this study was to assess whether different haemodynamic definitions of post‐capillary PH imply a different reversibility of PH in response to acute vasodilator administration in heart failure patients with reduced ejection fraction and PH (HFrEF‐PH).

Methods and results

Right heart catheterization and reversibility testing was performed in 156 HFrEF‐PH patients. Patients were classified as combined post‐capillary and pre‐capillary pulmonary hypertension (Cpc‐PH) vs. isolated post‐capillary pulmonary hypertension (Ipc‐PH) and on the basis of diastolic pulmonary gradient (DPG) ≥ 7 vs. < 7 mmHg or of transpulmonary gradient (TPG) >12 vs. ≤12 mmHg. After vasodilator administration, Cpc‐PH patients showed a greater per cent improvement in pulmonary vascular resistance (PVR), DPG and TPG as compared with Ipc‐PH patients (all Pint < 0.001); only pulmonary compliance (PCa) improved less in Cpc‐PH than in Ipc‐PH patients (Pint = 0.007). However, despite vasodilatation, Cpc‐PH patients remained in an unfavourable portion of the inverse hyperbolic relationship between PVR and PCa. The number of patients in whom PVR was reduced below 2.5 wood units was similar in Cpc‐PH, DPG ≥7 mmHg and TPG >12 mmHg groups (28.3, 26.7 and 18.9%, respectively).

Conclusion

Although substantial improvements in PVR, DPG and TPG were observed in Cpc‐PH patients after acute vasodilator administration, this response was associated with persistent abnormalities in the PVR vs. PCa relationship. The link between baseline right heart haemodynamics and pulmonary vascular disease remains elusive.
  相似文献   
57.
The needs of postregistration students pursuing degree-linked clinical courses have received little attention and there are few insights concerning their aspirations when they enrol on such courses. Thus the aim of this study was to explore postregistration students' perceptions of the specific needs of their patient/client group and to examine how they envisaged the course on which they had just enrolled might help them to meet these needs in addition to their own requirements for professional and personal development. Data were collected by group interview from 62 students enrolling on eight different postregistration courses, all employed in an acute hospital trust. The results were analysed inductively. They indicated that students had internalized the state of the healthcare market and were keenly aware of the need to fulfil the expectations of employers and the public, while fulfilling their own needs for education and pursuing their own professional and career trajectories. They appeared ambitious and yet appeared to demonstrate empathy for patients and their families and felt a tremendous desire to provide care of a high quality through the optimal development of technical expertise. Students' emphasis on the importance of keeping abreast of technological developments should not be lightly dismissed considering its prominent position within the acute areas where they were employed, especially as it did not replace their desire to promote the caring aspects of their work.  相似文献   
58.
Background and aimsHyperglycemia at hospital admission is a common finding in patients with STEMI. However, whether elevated acute glycemia in these patients may have a direct impact on worsening prognosis or is just a marker of a greater neurohormonal activation in response to the infarction is still unsettled.We sought to investigate the prognostic impact of hyperglycemia at hospital admission in patients undergoing primary PCI (pPCI) for STEMI, and the influence of the presence of diabetes mellitus (DM) on its prognostic impact.Methodsand Results, We enrolled 2958 consecutive STEMI patients treated by pPCI. Hyperglycemia was defined as plasma glucose >198 mg/dL (or >11 mmol/L). Patients with hyperglycemia showed a greater risk-profile; they also experienced a higher mortality both at univariable (17.6% vs 5.2%, p < 0.001) and multivariable (HR 1.9, 95%IC 1.5–2.9, p = 0.001) analysis. However, after stratification for DM presence, hyperglycemia resulted as an independent predictor of mortality only in patients without DM (HR 2, 95%IC 1.2–3.4, p = 0.01).ConclusionHyperglycemia in the setting of myocardial infarction treated with primary PCI in an independent predictor of all-cause mortality in patients without diabetes; in patients with diabetes, its prognostic impact seems attenuated.  相似文献   
59.
Background and aimsDespite elevated serum uric acid (eSUA) has been identified as independent risk factor for cardiovascular diseases, its prognostic value in the setting of ST-segment elevation myocardial infarction (STEMI) is still controversial. Although the mechanisms of this possible relationship are unsettled it has been suggested that eSUA could trigger the inflammatory response. This study sought to investigate the association between eSUA with short- and long-term mortality and with inflammatory response in patients with STEMI treated with primary percutaneous coronary intervention (pPCI).Methods and resultsBlood samples were collected on admission and at 24 and 48 h after pPCI: the inflammatory biomarkers C-reactive protein (CRP), neutrophil count and neutrophil to lymphocytes ratio (NLR) were considered. Baseline eSUA was defined as ≥6.8 mg/dl. Cumulative 30-days and 1-year mortalities were estimated using the Kaplan-Meyer analysis. Multivariable analyses were performed by Cox proportional hazard models.In the 2369 patients with STEMI considered, 30-day mortality was 5.8% among patients with eSUA and 2% among patient with normal SUA level (p < 0.001); 1-year mortality was 8.5% vs 4%, respectively (p < 0.001). At multivariable analyses eSUA was an independent predictor of 30-day mortality (HR 1.196, 95%CI 1.006–1.321, p = 0.042) and 1-year mortality (HR 1.178, 95%CI 1.052–1.320, p = 0.005). eSUA patients presented higher values in on admission CRP (p < 0.001) and in neutrophil count and NLR at 24 h (respectively, p = 0.020 and p < 0.001) and at 48 h (p = 0.018 and p < 0.001) compared to patients with normal SUA levels.ConclusionsElevated serum uric acid is associated with higher short- and long-term mortality and with a greater inflammatory response after reperfusion in patients with STEMI treated with primary PCI.  相似文献   
60.
BackgroundContrast associated-acute kidney injury (CA-AKI) has been associated with adverse outcomes after ST-segment elevation myocardial infarction (STEMI). However, early markers of CA-AKI are still needed to improve risk stratification. We investigated the association between elevated serum uric acid (eSUA) and CA-AKI in patients with STEMI treated with primary percutaneous coronary intervention (pPCI).Methods and resultsSerum creatinine (Scr) was measured at admission and 24, 48 and 72 h after pPCI. CA-AKI was defined as an increase of 25% (CA-AKI 25%) or 0.5 mg/dl (CA-AKI 0.5) of Scr level above the baseline after 48 h following contrast administration. Multivariable analyses to investigate CA-AKI predictors were performed by binary logistic regression and multivariable backward logistic regression model.In the 3023 patients considered, CA-AKI was more frequent among patients with eSUA as compared with patients with normal SUA levels, considering both CA-AKI definitions (CA-AKI25%: 20.8% vs 16.2%, p < 0.012; CA-AKI 0.5: 10.1% vs 5.8%, p < 0.001). The association between eSUA and CA-AKI was confirmed at multivariable analyses (CA-AKI 25%: odd ratio 1.32, 95% CI 1.03–1.69, p = 0.027; CA-AKI 0.5: odd ratio 1.76, 95% CI 1.11–2.79, p = 0.016).ConclusionElevated serum uric acid is associated with CA-AKI after reperfusion in patients with STEMI treated with pPCI.  相似文献   
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