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1.

Background  

The aim of this study was to investigate the effect of nanocrystalline hydroxyapatite (HA) coatings on the activity of osteoblasts.  相似文献   

2.

Introduction  

Hypoxia is a feature of the inflamed synovium in rheumatoid arthritis (RA). Intra-articular injection of hyaluronan (HA) may be considered a potential way to treat RA. However, the exact molecular mechanism of HA on decreased cellular responses to hypoxic environment is unclear. The present study has been designed to use the adjuvant-induced arthritis model to examine the effects of HA on the changes of immunohistochemical expressions of hypoxia-inducible factor-1alpha (HIF-1alpha), inducible nitric oxide synthase (iNOS), and matrix metalloproteinase-3 (MMP3) in the synovial tissues at the early phase of arthritic inflammation.  相似文献   

3.

Introduction  

Intraarticular hyaluronan (HA) is used clinically for symptomatic relief in patients with knee osteoarthritis (OA); however, the mechanism of action is unclear. In this study, we examined the effects of a single injection of HA on joint tissue pathology, mechanical allodynia and gait changes (measured by stride times) in a murine model of OA.  相似文献   

4.

Background

Recent studies have displayed increased interest in examining the relationship between personality traits and the onset, treatment response patterns, and relapse of depression. This study aimed to examine whether or not harm avoidance (HA) was a risk factor for postpartum depression measured by the Edinburgh Postnatal Depression Scale (EPDS) and the state dependency of HA.

Methods

Pregnant women (n=460; mean age 31.9±4.2 years) who participated in a prenatal program completed the EPDS as a measure of depressive state and the Temperament and Character Inventory (TCI) as a measure of HA during three periods: early pregnancy (T1), late pregnancy (around 36 weeks), and 1 month postpartum (T2). Changes in EPDS and HA scores from T1 to T2 were compared between the non depressive (ND) group and the postpartum depressive (PD) group.

Results

There was no significant difference in the level of HA between the ND and PD groups at T1. In the ND group, EPDS and HA scores did not change significantly from T1 to T2. In the PD group, both scores increased significantly from T1 to T2 (EPDS, p<0.0001; HA, p<0.048). In the ND and PD groups, a significant positive correlation was observed in changes in EPDS and HA scores from T1 to T2 (r=0.31, p=0.002).

Conclusions

These results suggest that HA cannot be considered a risk factor for the development of postpartum depression measured by EPDS. Furthermore, HA may be state dependent.  相似文献   

5.

Introduction

Patients with mean pulmonary artery pressures (mPAP) of 21 to 24 mm Hg have a so-called borderline elevation of mPAP (BoPAP)—a condition thought to represent early-stage pulmonary arterial vasculopathy. Based on the DETECT study, this post-hoc analysis examined patient characteristics of systemic sclerosis (SSc) patients with normal mPAP, BoPAP and elevated mPAP, fulfilling pulmonary arterial hypertension (PAH) criteria.

Methods

Adult patients with a duration of SSc more than 3 years, a diffusing capacity of the lung for carbon monoxide less than 60% predicted, and no previous diagnosis of any form of pulmonary hypertension (PH) underwent screening tests followed by right heart catheterization. Subjects were divided into three groups: normal mPAP, BoPAP, and PAH. Exploratory comparative and binary logistic regression analyses were performed for the BoPAP versus normal mPAP and PAH versus BoPAP groups.

Results

Of 244 patients evaluated, 148 (60%) had normal mPAP, 36 (15%) had BoPAP, and 60 (25%) had definite PAH. Univariable logistic regression (ULR) showed the mean tricuspid regurgitation velocity in patients with BoPAP to be intermediate between normal mPAP and PAH. In the ULR analyses BoPAP versus normal mPAP and PAH versus BoPAP, the statistically significant predictors were, amongst others: demographic, clinical, pulmonary function, echocardiographic and hemodynamic variables.

Conclusions

In this exploratory post-hoc analysis of the DETECT study population patients with BoPAP could be distinguished from patients with normal mPAP and PAH, and it appears that BoPAP may be an intermediate stage on the continuum between normal PA pressures and PAH.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-014-0493-1) contains supplementary material, which is available to authorized users.  相似文献   

6.
7.

Background

Liver dysfunction reflects the status of heart failure, with congestion and low perfusion of the liver serving as causative mechanisms. Previous studies demonstrated relationship between the results of liver function test and the prognosis in patients with heart failure. However, few studies have examined this relationship in patients with pulmonary arterial hypertension (PAH).

Methods

The subjects were 37 patients with PAH (8 men and 29 women; 18 with idiopathic PAH and 19 with connective tissue disease-associated PAH). A blood test was performed after a 3-month period free from hospitalization and without changes in functional class, treatment, heart sounds, body weight, or heart rate.

Results

In a mean follow-up period of 635 ± 510 days, 12 patients died due to heart failure, 2 died due to pulmonary hemorrhage, and 23 patients survived. Cox proportional hazard analyses identified functional class (p < 0.001), plasma concentration of brain natriuretic peptide (BNP) (p = 0.001), and hyperbilirubinemia (serum total bilirubin > 1.2 mg/dL; p < 0.001; hazard ratio = 13.31) as predictors of mortality. Patients with hyperbilirubinemia had a worse functional class (P = 0.003), a higher right atrial pressure (p < 0.001), a higher plasma concentration of BNP (p = 0.004), and a larger Doppler right ventricular index of the right ventricle (p = 0.041).

Conclusion

Elevated serum bilirubin is a risk factor for death in patients with PAH.  相似文献   

8.

Background  

The present study aimed to evaluate the efficacy of the hyaluronic acid (HA) binding assay in the selection of motile spermatozoa with normal morphology at high magnification (8400x).  相似文献   

9.

Rationale

Pulmonary arterial hypertension (PAH) is characterized by increased pulmonary vascular resistance leading to right ventricular failure and death. Recent studies have suggested that chronic inflammatory processes are involved in the pathogenesis of PAH. However, the molecular and cellular mechanisms driving inflammation have not been fully elucidated.

Objectives

To elucidate the roles of high mobility group box 1 protein (HMGB1), a ubiquitous DNA-binding protein with extracellular pro-inflammatory activity, in a rat model of PAH.

Methods

Male Sprague-Dawley rats were administered monocrotaline (MCT). Concentrations of HMGB1 in bronchoalveolar lavage fluid (BALF) and serum, and localization of HMGB1 in the lung were examined over time. The protective effects of anti-HMGB1 neutralizing antibody against MCT-induced PAH were tested.

Results

HMGB1 levels in BALF were elevated 1 week after MCT injection, and this elevation preceded increases of other pro-inflammatory cytokines, such as TNF-α, and the development of PAH. In contrast, serum HMGB1 levels were elevated 4 weeks after MCT injection, at which time the rats began to die. Immunohistochemical analyses indicated that HMGB1 was translocated to the extranuclear space in periarterial infiltrating cells, alveolar macrophages, and bronchial epithelial cells of MCT-injected rats. Anti-HMGB1 neutralizing antibody protected rats against MCT-induced lung inflammation, thickening of the pulmonary artery wall, and elevation of right ventricular systolic pressure, and significantly improved the survival of the MCT-induced PAH rats.

Conclusions

Our results identify extracellular HMGB1 as a promoting factor for MCT-induced PAH. The blockade of HMGB1 activity improved survival of MCT-induced PAH rats, and thus might be a promising therapy for the treatment of PAH.  相似文献   

10.

Background

Previous meta-analyses of treatments for pulmonary arterial hypertension (PAH) have not shown mortality benefit from any individual class of medication.

Methods

MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials were searched from inception through November 2009 for randomized trials that evaluated any pharmacotherapy in the treatment of PAH. Reference lists from included articles and recent review articles were also searched. Analysis included randomized placebo controlled trials of at least eight weeks duration and studies comparing intravenous medication to an unblinded control group.

Results

1541 unique studies were identified and twenty-four articles with 3758 patients were included in the meta-analysis. Studies were reviewed and data extracted regarding study characteristics and outcomes. Data was pooled for three classes of medication: prostanoids, endothelin-receptor antagonists (ERAs), and phosphodiesterase type 5 (PDE5) inhibitors. Pooled relative risks (RRs) and 95% confidence intervals (CIs) were calculated for mortality, 6-minute walk distance, dyspnea scores, hemodynamic parameters, and adverse effects. Mortality in the control arms was a combined 4.2% over the mean study length of 14.9 weeks. There was significant mortality benefit with prostanoid treatment (RR 0.49, CI 0.29 to 0.82), particularly comparing intravenous agents to control (RR 0.30, CI 0.14 to 0.63). Mortality benefit was not observed for ERAs (RR 0.58, CI 0.21 to 1.60) or PDE5 inhibitors (RR 0.30, CI 0.08 to 1.08). All three classes of medication improved other clinical and hemodynamic endpoints. Adverse effects that were increased in treatment arms include jaw pain, diarrhea, peripheral edema, headache, and nausea in prostanoids; and visual disturbance, dyspepsia, flushing, headache, and limb pain in PDE5 inhibitors. No adverse events were significantly associated with ERA treatment.

Conclusions

Treatment of PAH with prostanoids reduces mortality and improves multiple other clinical and hemodynamic outcomes. ERAs and PDE5 inhibitors improve clinical and hemodynamic outcomes, but have no proven effect on mortality. The long-term effects of all PAH treatment requires further study.  相似文献   

11.

Background  

The interpandemic evolution of the influenza A virus hemagglutinin (HA) protein is commonly considered a paragon of rapid evolutionary change under positive selection in which amino acid replacements are fixed by virtue of their effect on antigenicity, enabling the virus to evade immune surveillance.  相似文献   

12.

Introduction  

Angiotensin-converting enzyme (ACE) 2, a homolog of ACE, converts angiotensin (Ang) II into Ang(1-7), and the vasoprotective effects of Ang(1-7) have been documented. We explored the hypothesis that serum autoantibodies to ACE2 predispose patients with connective tissue diseases to constrictive vasculopathy, pulmonary arterial hypertension (PAH), or persistent digital ischemia.  相似文献   

13.

Background

This study investigated whether the hepatocyte growth factor (HGF) genetically modified marrow-mesenchymal stem cells (MSCs) transplantation could offer a therapeutic benefit for pulmonary arterial hypertension (PAH).

Methodology

Three weeks after monocrotaline administration, Sprague-Dawley rats were randomly divided into the following groups: PAH (n=10), MSCs (5×106 MSCs injected into the jugular veins, n=10), HGF (5×106 MSCs transfected with Ad-HGF into the jugular veins, n=10). Another three weeks later, hemodynamic changes and histomorphology were observed. Electron microscopy and immunofluorescence were also used to observe changes in the gap junctions of the heart.

Results

Compared with the PAH and MSC groups, hemodynamic parameters improved significantly in the MSC-HGF group. Right ventricular hypertrophy was improved as measured by the RV/LV weight and thickness ratios. Histologically, cardiac myocytes and cell nuclei recovered and interstitial fibrosis decreased in the MSC and MSC-HGF groups. Under electron microscopy, the gap junctions exhibited a disorganised morphology in the PAH group and the number of gap junctions was lower in this group than in the other groups. The distribution of connexins 43 and 40 were improved in the MSC-HGF group.

Conclusions

MCT-induced PAH can be treated and improved by HGF genetically modified MSCs, which may occur via connexin remodeling.  相似文献   

14.

Background

Human hyaluronic acid (HA) molecules are synthesized by three membrane spanning Hyaluronic Acid Synthases (HAS1, HAS2 and HAS3). Of the three, HAS1 is found to be localized more into the cytoplasmic space where it synthesizes intracellular HA. HA is a ubiquitous glycosaminoglycan, mainly present in the extracellular matrix (ECM) and on the cell surface, but are also detected intracellularly. Accumulation of HA in cancer cells, the cancer-surrounding stroma, and ECM is generally considered an independent prognostic factors for patients. Higher HA production also correlates with higher tumor grade and more genetic heterogeneity in multiple cancer types which is known to contribute to drug resistance and results in treatment failure. Tumor heterogeneity and intra-tumor clonal diversity are major challenges for diagnosis and treatment. Identification of the driver pathway(s) that initiate genomic instability, tumor heterogeneity and subsequent phenotypic/clinical manifestations, are fundamental for the diagnosis and treatment of cancer. Thus far, no evidence was shown to correlate intracellular HA status (produced by HAS1) and the generation of genetic diversity in tumors.

Methods

We tested different cell lines engineered to induce HAS1 expression. We measured the epithelial traits, centrosomal abnormalities, micronucleation and polynucleation of those HAS1-expressing cells. We performed real-time PCR, 3D cell culture assay, confocal microscopy, immunoblots and HA-capture methods.

Results

Our results demonstrate that overexpression of HAS1 induces loss of epithelial traits, increases centrosomal abnormalities, micronucleation and polynucleation, which together indicate manifestation of malignant transformation, intratumoral genetic heterogeneity, and possibly create suitable niche for cancer stem cells generation.

Conclusions

The intracellular HA produced by HAS1 can aggravate genomic instability and intratumor heterogeneity, pointing to a fundamental role of intracellular HA in cancer initiation and progression.
  相似文献   

15.

Objective

This study charted incidence trends of hospital-acquired (HA) pneumonia, bacteraemia and urinary tract infections (UTI) in a haematology department.

Methods

Prospective surveillance of hospital-acquired infections (HAI) was undertaken in a 42-bed haematology department of a university hospital. All patients hospitalized ≥48 hours between 1st January 2004 and 31st December 2010 were included. Definitions of HAI were based on a standardized protocol. The incidence was the number of events per 1000 patient-days at risk; only the first HAI was counted. Multivariate Poisson regression was fitted to assess temporal trends.

Results

Among 3 355 patients (58 063 patient-days at risk) included, 1 055 (31%) had HAI. The incidence of HA pneumonia, HA bacteraemia and HA UTI was respectively 3.3, 12.0 and 2.9 per 1000 patient-days at risk. HA bacteraemia incidence increased by 11% (95% confidence interval: +6%, +15%, P<0.001) per year, independently of neutropenia, central venous catheterization (CVC) and haematological disease. The incidences of HA pneumonia and HA UTI were stable. The most frequently isolated pathogens were Aspergillus spp. (59.2%) for pneumonia, coagulase-negative Staphylococcus (44.2%) for bacteraemia and enterobacteria (60%) for UTI.

Conclusion

The incidence of bacteraemia increased, indicating that factors other than CVC exposure, including chemotherapy with its impact on the immune system, could explain this trend. Further analytic studies are needed to explore the factors that could explain this trend.  相似文献   

16.

Rationale

Greater levels of prenatal exposure to polycyclic aromatic hydrocarbon (PAH) have been associated with childhood obesity in epidemiological studies. However, the underlying mechanisms are unclear.

Objectives

We hypothesized that prenatal PAH over-exposure during gestation would lead to weight gain and increased fat mass in offspring and grand-offspring mice. Further, we hypothesized that altered adipose gene expression and DNA methylation in genes important to adipocyte differentiation would be affected.

Materials and Methods

Pregnant dams were exposed to a nebulized PAH mixture versus negative control aerosol 5 days a week, for 3 weeks. Body weight was recorded from postnatal day (PND) 21 through PND60. Body composition, adipose cell size, gene expression of peroxisome proliferator-activated receptor (PPAR) γ, CCAAT/enhancer-binding proteins (C/EBP) α, cyclooxygenase (Cox)-2, fatty acid synthase (FAS) and adiponectin, and DNA methylation of PPAR γ, were assayed in both the offspring and grand-offspring adipose tissue.

Findings

Offspring of dams exposed to greater PAH during gestation had increased weight, fat mass, as well as higher gene expression of PPAR γ, C/EBP α, Cox2, FAS and adiponectin and lower DNA methylation of PPAR γ. Similar differences in phenotype and DNA methylation extended through the grand-offspring mice.

Conclusions

Greater prenatal PAH exposure was associated with increased weight, fat mass, adipose gene expression and epigenetic changes in progeny.  相似文献   

17.

Background

HIV infection is an independent risk factor for PAH, but the underlying pathogenesis remains unclear. ET-1 is a robust vasoconstrictor and key mediator of pulmonary vascular homeostasis. Higher levels of ET-1 predict disease severity and mortality in other forms of PAH, and endothelin receptor antagonists are central to treatment, including in HIV-associated PAH. The direct relationship between ET-1 and PAH in HIV-infected individuals is not well described.

Methods

We measured ET-1 and estimated pulmonary artery systolic pressure (PASP) with transthoracic echocardiography (TTE) in 106 HIV-infected individuals. Participants with a PASP ≥ 30 mmHg (n = 65) underwent right heart catheterization (RHC) to definitively diagnose PAH. We conducted multivariable analysis to identify factors associated with PAH.

Results

Among 106 HIV-infected participants, 80% were male, the median age was 52 years and 77% were on antiretroviral therapy. ET-1 was significantly associated with higher values of PASP [14% per 0.1 pg/mL increase in ET-1, p = 0.05] and PASP ≥ 30 mmHg [PR (prevalence ratio) = 1.24, p = 0.012] on TTE after multivariable adjustment for PAH risk factors. Similarly, among the 65 individuals who underwent RHC, ET-1 was significantly associated with higher values of mean pulmonary artery pressure and PAH (34%, p = 0.003 and PR = 2.43, p = 0.032, respectively) in the multivariable analyses.

Conclusions

Higher levels of ET-1 are independently associated with HIV-associated PAH as hemodynamically assessed by RHC. Our findings suggest that excessive ET-1 production in the setting of HIV infection impairs pulmonary endothelial function and contributes to the development of PAH.  相似文献   

18.

Background

Although nurses play an important role in humanitarian aid and disaster relief (HA/DR), little is known about the nursing activities that are performed in HA/DR. We aimed to clarify the nursing activities performed by Japanese nurses in HA/DR and to examine the factors associated with the frequency of nursing activities.

Methods

A self-administered questionnaire survey was completed by 147 nurses with HA/DR experience. The survey extracted information on demographic characteristics, past experience (e.g., disaster medical training experience, HA/DR experience), circumstances surrounding their dispatched to HA/DR (e.g., team size, disaster type, post-disaster phase, mission term), and the frequency of nursing activities performed under HA/DR. The frequency of nursing activities was rated on a 5-point Likert scale. Evaluation of nursing activities was conducted based on the “nursing activity score”, which represents the frequency of each nursing activity. Factors related to the nursing activity score were evaluated by multiple logistic regression analysis.

Results

Nurses were involved in 27 nursing activities in HA/DR, 10 of which were performed frequently. On analysis, factors significantly associated with nursing activity score were nursing license as a registered nurse (OR 7.79, 95% CI 2.95–20.57), two or more experiences with disaster medical training (OR 2.90 95%, CI 1.12–7.49) and a post-disaster phase of three weeks or longer (OR 8.77, 95% CI 2.59–29.67).

Conclusions

These results will contribute to the design of evidence-based disaster medical training that improves the quality of nursing activities.  相似文献   

19.

Background

Although inflammation is an important feature of pulmonary arterial hypertension (PAH), the usefulness of local inflammatory markers as biomarkers for PAH is unknown. In this study, we tested whether plasma concentrations of human pentraxin 3 (PTX3), a local inflammatory marker, would be a useful biomarker for detecting PAH.

Methods

Plasma PTX3 concentrations were evaluated in 50 PAH patients (27 with idiopathic PAH, 17 with PAH associated with connective tissue disease (CTD-PAH), and six with congenital heart disease), 100 age and sex-matched healthy controls, and 34 disease-matched CTD patients without PAH. Plasma concentrations of B-type natriuretic peptide (BNP) and C-reactive protein (CRP) were also determined.

Results

Mean PTX3 levels were significantly higher in all PAH patients than in the healthy controls (4.40±0.37 vs. 1.94±0.09 ng/mL, respectively; P<0.001). Using a threshold level of 2.84 ng/mL, PTX3 yielded a sensitivity of 74.0% and a specificity of 84.0% for the detection of PAH. In CTD-PAH patients, mean PTX3 concentrations were significantly higher than in CTD patients without PAH (5.02±0.69 vs. 2.40±0.14 ng/mL, respectively; P<0.001). There was no significant correlation between plasma levels of PTX3 and BNP or CRP. Receiver operating characteristic (ROC) curves for screening PAH in patients with CTD revealed that PTX3 (area under the ROC curve 0.866) is superior to BNP. Using a PTX3 threshold of 2.85 ng/mL maximized true-positive and false-negative results (sensitivity 94.1%, specificity 73.5%).

Conclusion

Plasma concentrations of PTX3 may be a better biomarker of PAH than BNP, especially in patients with CTD.  相似文献   

20.

Background  

Hyaluronic acid (HA) is present in many tissues; its presence in serum may be related to certain inflammatory conditions, tissue damage, sepsis, liver malfunction and some malignancies. In the present work, our goal was to investigate the significance of hyaluronic acid effect on erythrocyte flow properties. Therefore we performed in vitro experiments incubating red blood cells (RBCs) with several HA concentrations. Afterwards, in order to corroborate the pathophysiological significance of the results obtained, we replicated the in vitro experiment with ex vivo RBCs from diagnosed rheumatoid arthritis (RA) patients, a serum HA-increasing pathology.  相似文献   

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