353 research outputs found

    The effect of cross-contamination in the sequential interfacial polymerization on the RO performance of polyamide bilayer membranes

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    International audienceIn this study, hexafluoroalcohol-containing polyamide layer (HFAPA) was prepared on top of a conventional polyamide under-layer (REFPA) via sequential interfacial polymerization (SIP) to improve RO separation behavior, and the performance of the resulting bilayer membrane was thoroughly optimized by investigating the effect of cross-contamination in the SIP process. When several coupons of the polyamide bilayer membrane were prepared by SIP of MPD(aq), TMC(hx) and hexafluoroalcohol-containing diamine (HFAMDA)(aq) in the manner of subsequent membrane dipping, unreacted MPD monomer (mostly captured in the porous PSF support) carried over from the 1st interfacial reaction dissolved and accumulated in the 2nd aqueous solution as verified by UV spectroscopic analysis. The MPD contaminant then participated in the 2nd interfacial reaction, forming copolyamide with HFAMDA monomer onto the REFPA. Depending on the amount of MPD contaminant accumulated in the 2nd aqueous solution, the composition of the resulting co-polyamide in the top-layer varied, causing a significant variation of RO performance; the flux was gradually decreased with the increase of MPD contaminants while the salt rejection slightly increased (from 1st coupon toward 4th coupon). This result indicated that a trace amount of MPD contaminant may be necessary to maximize RO separation behavior. Through in-depth performance evaluation of polyamide bilayer membranes prepared by adding various known-amount of MPD into 2nd HFAMDA solution, and also by applying a frame process (2nd amine solution was applied only top surface of membrane) to eliminate uncontrollable MPD contamination, we have successfully demonstrated consistent RO performance, and identified an optimum material composition to provide superior separation performance. The bilayer membrane prepared by adding 1.2 mol% of MPD to the total amount of HFAMDA in the 2nd aqueous solution showed 99.8% NaCl rejection with the water flux of 45 LMH under the cross-flow filtration performed with 2000 ppm NaCl solution at 400 psi, 25 °C

    Prevalence of congenital coronary artery anomalies and variants in 726 consecutive patients based on 64-slice coronary computed tomography angiography

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      Background: Coronary computed tomography angiography (CCTA) is helpful in making a precise noninvasive evaluation of coronary anatomy, allowing concomitant evaluation of other cardiac structures. The aim of this study was to determine the prevalence of coronary artery variations detected by 64-slice mutidetector CT. Materials and methods: The results of ECG-gated CCTA in 726 consecutive patients (mean age 58 years) were analysed retrospectively. The main indicationsfor CCTA were a typical chest pain, angina pectoris, screening for coronary artery disease and determination of the patency of bypass grafts or stents. Acquisitionwas performed with a 64-detector CT scanner with retrospective ECG gating. Imaging results were assessed by experienced cardiovascular radiologist. Results: The overall incidence of coronary artery anomalies was 1.1% (8 out of 726 participants). The most common anomaly was an anomalous origin of the circumflex artery from the right coronary sinus with a retroaortic course (4 patients,0.6%), followed by origin of right coronary artery from the left coronary sinus (2 patients, 0.3%). One patient with abnormal origin of the left main artery from the right coronary sinus (0.1%) and 1 patient with a circumflex artery origin from the proximal segment of the right coronary artery (0.1%) were observed, both with retroartic course. Conclusions: CCTA is a noninvasive imaging technique useful for the precise evaluation of variations of the coronary arteries. This study shows similar results to other reports on this subject.

    Association between the c.*229C>T polymorphism of the topoisomerase IIb binding protein 1 (TopBP1) gene and breast cancer

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    Topoisomerase IIb binding protein 1 (TopBP1) is involved in cell survival, DNA replication, DNA damage repair and cell cycle checkpoint control. The biological function of TopBP1 and its close relation with BRCA1 prompted us to investigate whether alterations in the TopBP1 gene can influence the risk of breast cancer. The aim of this study was to examine the association between five polymorphisms (rs185903567, rs116645643, rs115160714, rs116195487, and rs112843513) located in the 30UTR region of the TopBP1 gene and breast cancer risk as well as allele-specific gene expression. Five hundred thirty-four breast cancer patients and 556 population controls were genotyped for these SNPs. Allele-specific Top- BP1 mRNA and protein expressions were determined by using real time PCR and western blotting methods, respectively. Only one SNP (rs115160714) showed an association with breast cancer. Compared to homozygous common allele carriers, heterozygous and homozygous for the T variant had significantly increased risk of breast cancer (adjusted odds ratio = 3.81, 95 % confidence interval: 1.63–8.34, p = 0.001). Mean TopBP1 mRNA and protein expression were higher in the individuals with the CT or TT genotype. There was a significant association between the rs115160714 and tumor grade and stage. Most carriers of minor allele had a high grade (G3) tumors classified as T2-T4N1M0. Our study raises a possibility that a genetic variation of TopBP1 may be implicated in the etiology of breast cancer

    Persistent left superior vena cava with an absent right superior vena cava in a 72-year-old male with multivessel coronary artery disease

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    Congenital anomalies of systemic veins are usually asymptomatic and foundincidentally during ultrasonography, computed tomography (CT) or magneticresonance examinations performed for other clinical indications. Persistent leftsuperior vena cava (PLSVC) with absent right superior vena cava (RSVC) is thecongenital aberration in the thoracic venous system which occurs in only 0.09%to 0.13% of patients who have congenital heart defects. In this paper, we presentthe extremely rare case of a 72-year-old male with PLSVC associated withan absence of RSVC, referred for coronary CT angiography. Multidetector CTangiography is a powerful tool for the detection of venous anomalies, which isessential before invasive procedures such as the implantation of pacemakers

    How does gender influence the recognition of cardiovascular risk and adherence to self-care recommendations? : a study in polish primary care

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    Background: Studies have shown a correlation between gender and an ability to change lifestyle to reduce the risk of disease. However, the results of these studies are ambiguous, especially where a healthy lifestyle is concerned. Additionally, health behaviors are strongly modified by culture and the environment. Psychological factors also substantially affect engagement with disease-related lifestyle interventions. This study aimed to examine whether there are differences between men and women in the frequency of health care behavior for the purpose of reducing cardiovascular risk (CVR), as well as cognitive appraisal of this type of risk. We also aimed to identify the psychological predictors of engaging in recommended behavior for reducing the risk of cardiovascular disease after providing information about this risk in men and women. Methods: A total of 134 consecutive eligible patients in a family practice entered a longitudinal study. At initial consultation, the individual’s CVR and associated health burden was examined, and preventive measures were recommended by the physician. Self-care behavior, cognitive appraisal of risk, and coping styles were then assessed using psychological questionnaires. Six months after the initial data collection, the frequency of subjects’ self-care behavior was examined. Results: We found an increase in health care behavior after providing information regarding the rate of CVR in both sexes; this increase was greater for women than for men. Women followed self-care guidelines more often than men, particularly for preventive measures and dietary advice. Women were more inclined to recognize their CVR as a challenge. Coping style, cognitive appraisal, age, level of health behaviors at baseline and CVR values accounted for 48% of the variance in adherence to self-care guidelines in women and it was 52% in men. In women, total risk of CVD values were most important, while in men, cognitive appraisal of harm/loss was most important. Conclusions: Different predictors of acquisition of health behavior are encountered in men and women. Our results suggest that gender-adjusted motivation models influencing the recognition process need to be considered to optimize compliance in patients with CVR

    Treatment of Older Patients with Mantle-Cell Lymphoma

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    BACKGROUND: The long-term prognosis for older patients with mantle-cell lymphoma is poor. Chemoimmunotherapy results in low rates of complete remission, and most patients have a relapse. We investigated whether a fludarabine-containing induction regimen improved the complete-remission rate and whether maintenance therapy with rituximab prolonged remission. METHODS: We randomly assigned patients 60 years of age or older with mantle-cell lymphoma, stage II to IV, who were not eligible for high-dose therapy to six cycles of rituximab, fludarabine, and cyclophosphamide (R-FC) every 28 days or to eight cycles of rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) every 21 days. Patients who had a response underwent a second randomization to maintenance therapy with rituximab or interferon alfa, each given until progression. RESULTS: Of the 560 patients enrolled, 532 were included in the intention-to-treat analysis for response, and 485 in the primary analysis for response. The median age was 70 years. Although complete-remission rates were similar with R-FC and R-CHOP (40% and 34%, respectively; P=0.10), progressive disease was more frequent with R-FC (14%, vs. 5% with R-CHOP). Overall survival was significantly shorter with R-FC than with R-CHOP (4-year survival rate, 47% vs. 62%; P=0.005), and more patients in the R-FC group died during the first remission (10% vs. 4%). Hematologic toxic effects occurred more frequently in the R-FC group than in the R-CHOP group, but the frequency of grade 3 or 4 infections was balanced (17% and 14%, respectively). In 274 of the 316 patients who were randomly assigned to maintenance therapy, rituximab reduced the risk of progression or death by 45% (in remission after 4 years, 58%, vs. 29% with interferon alfa; hazard ratio for progression or death, 0.55; 95% confidence interval, 0.36 to 0.87; P=0.01). Among patients who had a response to R-CHOP, maintenance therapy with rituximab significantly improved overall survival (4-year survival rate, 87%, vs. 63% with interferon alfa; P=0.005). CONCLUSIONS: R-CHOP induction followed by maintenance therapy with rituximab is effective for older patients with mantle-cell lymphom

    Quality control of B-lines analysis in stress Echo 2020

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    Background The effectiveness trial “Stress echo (SE) 2020” evaluates novel applications of SE in and beyond coronary artery disease. The core protocol also includes 4-site simplified scan of B-lines by lung ultrasound, useful to assess pulmonary congestion. Purpose To provide web-based upstream quality control and harmonization of B-lines reading criteria. Methods 60 readers (all previously accredited for regional wall motion, 53 B-lines naive) from 52 centers of 16 countries of SE 2020 network read a set of 20 lung ultrasound video-clips selected by the Pisa lab serving as reference standard, after taking an obligatory web-based learning 2-h module ( http://se2020.altervista.org ). Each test clip was scored for B-lines from 0 (black lung, A-lines, no B-lines) to 10 (white lung, coalescing B-lines). The diagnostic gold standard was the concordant assessment of two experienced readers of the Pisa lab. The answer of the reader was considered correct if concordant with reference standard reading ±1 (for instance, reference standard reading of 5 B-lines; correct answer 4, 5, or 6). The a priori determined pass threshold was 18/20 (≥ 90%) with R value (intra-class correlation coefficient) between reference standard and recruiting center) > 0.90. Inter-observer agreement was assessed with intra-class correlation coefficient statistics. Results All 60 readers were successfully accredited: 26 (43%) on first, 24 (40%) on second, and 10 (17%) on third attempt. The average diagnostic accuracy of the 60 accredited readers was 95%, with R value of 0.95 compared to reference standard reading. The 53 B-lines naive scored similarly to the 7 B-lines expert on first attempt (90 versus 95%, p = NS). Compared to the step-1 of quality control for regional wall motion abnormalities, the mean reading time per attempt was shorter (17 ± 3 vs 29 ± 12 min, p < .01), the first attempt success rate was higher (43 vs 28%, p < 0.01), and the drop-out of readers smaller (0 vs 28%, p < .01). Conclusions Web-based learning is highly effective for teaching and harmonizing B-lines reading. Echocardiographers without previous experience with B-lines learn quickly.info:eu-repo/semantics/publishedVersio

    Perivascular-like cells contribute to the stability of the vascular network of osteogenic tissue formed from cell sheet-based constructs

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    In recent years several studies have been supporting the existence of a close relationship in terms of function and progeny between Mesenchymal Stem Cells (MSCs) and Pericytes. This concept has opened new perspectives for the application of MSCs in Tissue Engineering (TE), with special interest for the pre-vascularization of cell dense constructs. In this work, cell sheet technology was used to create a scaffold-free construct composed of osteogenic, endothelial and perivascular-like (CD146+) cells for improved in vivo vessel formation, maturation and stability. The CD146 pericyte-associated phenotype was induced from human bone marrow mesenchymal stem cells (hBMSCs) by the supplementation of standard culture medium with TGF-b1. Co-cultured cell sheets were obtained by culturing perivascular-like (CD146+) cells and human umbilical vein endothelial cells (HUVECs) on an hBMSCs monolayer maintained in osteogenic medium for 7 days. The perivascular-like (CD146+) cells and the HUVECs migrated and organized over the collagen-rich osteogenic cell sheet, suggesting the existence of cross-talk involving the co-cultured cell types. Furthermore the presence of that particular ECM produced by the osteoblastic cells was shown to be the key regulator for the singular observed organization. The osteogenic and angiogenic character of the proposed constructs was assessed in vivo. Immunohistochemistry analysis of the explants revealed the integration of HUVECs with the host vasculature as well as the osteogenic potential of the created construct, by the expression of osteocalcin. Additionally, the analysis of the diameter of human CD146 positive blood vessels showed a higher mean vessel diameter for the co-cultured cell sheet condition, reinforcing the advantage of the proposed model regarding blood vessels maturation and stability and for the in vitro pre-vascularization of TE constructs.Funding provided by Fundacao para a Ciencia e a Tecnologia project Skingineering (PTDC/SAU-OSM/099422/2008). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

    Design, synthesis, and antimicrobial evaluation of a novel bone-targeting bisphosphonate-ciprofloxacin conjugate for the treatment of osteomyelitis biofilms

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    Osteomyelitis is a major problem worldwide and is devastating due to the potential for limb-threatening sequelae and mortality. Osteomyelitis pathogens are bone-attached biofilms, making antibiotic delivery challenging. Here we describe a novel osteoadsorptive bisphosphonate-ciprofloxacin conjugate (BV600022), utilizing a “target and release” chemical strategy, which demonstrated a significantly enhanced therapeutic index versus ciprofloxacin for the treatment of osteomyelitis in vivo. In vitro antimicrobial susceptibility testing of the conjugate against common osteomyelitis pathogens revealed an effective bactericidal profile and sustained release of the parent antibiotic over time. Efficacy and safety were demonstrated in an animal model of periprosthetic osteomyelitis, where a single dose of 10 mg/kg (15.6 μmol/kg) conjugate reduced the bacterial load by 99% and demonstrated nearly an order of magnitude greater activity than the parent antibiotic ciprofloxacin (30 mg/kg, 90.6 μmol/kg) given in multiple doses. Conjugates incorporating a bisphosphonate and an antibiotic for bone-targeted delivery to treat osteomyelitis biofilm pathogens constitute a promising approach to providing high bone-antimicrobial potency while minimizing systemic exposure
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