Effects of thrice weekly nocturnal hemodialysis on arterial stiffness

ObjectiveIn this study, we compared the changes in arterial stiffness in chronic hemodialysis patients treated with 8-h vs. 4-h thrice weekly in-center hemodialysis.MethodsSixty prevalent chronic hemodialysis patients assigned to 8-h nocturnal in-center thrice weekly HD (NHD) and 60 control cases assigned to 4-h thrice weekly conventional HD (CHD) were followed for one year. Radial–carotid pulse wave velocity, augmentation index and echocardiography were performed at baseline and 12^th month.ResultsMean age of the patients was 49 ± 11 years, 30.8% were female, 27.5% had diabetes mellitus and mean dialysis vintage was 57 ± 47 months. Baseline demographical, clinical and laboratory parameters were similar between groups. During a mean follow-up of 15.0 ± 0.1 months, blood pressure remained similar in both groups while the number of mean daily anti-hypertensive substances decreased in the NHD group. In the NHD group, time-averaged serum phosphorus and calcium–phosphorus product were lower than the CHD group. Pulse wave velocity and augmentation index decreased in the NHD group (from 11.02 ± 2.51 m/s to 9.61 ± 2.39 m/s and from 28.8 ± 10.3% to 26.2 ± 12.1%; p = 0.008 and p = 0.04, respectively). While augmentation index increased in the CHD group (28.0 ± 9.4 to 31.0 ± 10.7%, p = 0.02), pulse wave velocity did not change. Subendocardial viability ratio and ejection duration improved in the NHD group (from 135 ± 28 to 143 ± 25%, p = 0.01 and from 294 ± 34 ms to 281 ± 34 ms, p = 0.003, respectively), accompanied by regression of left ventricular mass index. In multiple stepwise linear regression analyses, NHD was associated with improvements in augmentation index, ejection duration and subendocardial viability ratio.ConclusionsThese data indicate that arterial stiffness is ameliorated by implementation of longer hemodialysis sessions.     

Peptide tag forming a rapid covalent bond to a protein, through engineering a bacterial adhesin

Protein interactions with peptides generally have low thermodynamic and mechanical stability. Streptococcus pyogenes fibronectin-binding protein FbaB contains a domain with a spontaneous isopeptide bond between Lys and Asp. By splitting this domain and rational engineering of the fragments, we obtained a peptide (SpyTag) which formed an amide bond to its protein partner (SpyCatcher) in minutes. Reaction occurred in high yield simply upon mixing and amidst diverse conditions of pH, temperature, and buffer. SpyTag could be fused at either terminus or internally and reacted specifically at the mammalian cell surface. Peptide binding was not reversed by boiling or competing peptide. Single-molecule dynamic force spectroscopy showed that SpyTag did not separate from SpyCatcher until the force exceeded 1 nN, where covalent bonds snap. The robust reaction conditions and irreversible linkage of SpyTag shed light on spontaneous isopeptide bond formation and should provide a targetable lock in cells and a stable module for new protein architectures.     

The Effects of Individual and Organisational Characteristics on the Level of Burnout Level: A Research on Physicians and Nurses in Turkey

In the Turkish health care system and hospitals it is very common to witness role conflict and ambiguity among health care personnel. Often this is due to a lack of clarity as to what is expected and required of them. The unfortunate and unavoidable result is a high level of burnout caused by uncertain working conditions in Turkish hospitals. The objectives of this study were to determine the level of role conflict, role ambiguity, and burnout of physicians and nurses working in hospitals, to see the relationship between role conflict, ambiguity and burnout level, to reveal the effects of organisational and indvidual characteristics on the burnout level of physicians and nurses. The study was conducted in three hospitals attached to the Ministry of Health (MoH) of Turkey. 149 nurses and 83 physicians were included in the sample of this study although several efforts of reminders and additional visits to the hospitals to increase the response rate. Structural Equational Modelling (SEM) was chosen to estimate the effects of certain selected individual and organisational variables that were determined by a set of correlation and biovariate analyses on role conflict and ambiguity as well as the burnout level. The SEM results showed that working in surgical units, having less working experience and choosing the profession unwillingly had significant and negative direct effects on the burnout level of the physicians and nurses in the sample of this study. Decreasing the level of role conflict and ambiguity would serve to decrease the level of burnout. In order to decrease the level of role conflict, ambiguity, and burn out level for nurses and physicans, serious efforts must be made to clarify role definitions, increase resources, and employ conflict management methods.     

Relation of Neutrophil/Lymphocyte Ratio to Coronary Flow to In-Hospital Major Adverse Cardiac Events in Patients With ST-Elevated Myocardial Infarction Undergoing Primary Coronary Intervention

With the growing understanding of the role of inflammation in patients with atherosclerotic disease, studies have focused on high-sensitivity C-reactive protein (hs-CRP) and other inflammatory markers in their association with outcomes in ST-segment elevation myocardial infarction. The goal of this study was to investigate the association of the neutrophil/lymphocyte (N/L) ratio and in-hospital major adverse cardiac events (MACEs) in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention (PCI). The association of hs-CRP and N/L ratio on admission with Thrombolysis In Myocardial Infarction (TIMI) flow grade after PCI was assessed in 418 consecutive primary patients with PCI. The N/L ratio was significantly higher in the no-reflow group (TIMI grade 0/1/2 flow, n = 158) compared to that of the normal-flow group (TIMI grade 3 flow, n = 260, 4.6 ± 1.7 vs 3.1 ± 1.9, p <0.001). In-hospital MACEs were significantly higher in patients with no reflow (23% vs 7%, p <0.001). There was a significant and positive correlation between hs-CRP and N/L ratio (r = 0.657, p <0.001). In receiver operating characteristic analysis, N/L ratio >3.3 predicted no reflow with 74% sensitivity and 83% specificity. In a multivariate regression model, N/L ratio remained an independent correlate of no reflow (odds ratio [OR] 1.54, 95% confidence interval [CI] 1.34 to 1.76, p <0.001) and in-hospital MACEs (OR 1.14, 95% CI 0.98 to 1.32, p = 0.043). The N/L ratio, an inexpensive and easily measurable laboratory variable, is independently associated with the development of no reflow and in-hospital MACEs in patients with ST-segment elevation myocardial infarction undergoing primary PCI.     

Increased carotid intima-media thickness is associated with higher SYNTAX score

The main purpose of this study was to investigate the relation between carotid intima-media thickness (CIMT) and coronary artery disease (CAD) complexity. Consecutive patients (n = 360) with CAD confirmed by coronary angiography were enrolled. Mean CIMT and the overall SYNTAX score (SXscore) were 0.87 ± 0.12 mm and 15 ± 9, respectively. In univariate analysis, there was a significant correlation between the overall SXscore and CIMT (r = .42, P < .001), age (r = .23, P < .001), hypertension (r = .27, P = 0.001), diabetes (r = 0.11, P = 0.02), smoking (r = .24, P = .01), dyslipidemia (r = .2, P = 0.03), and β-blocker use (r = .19, P < .001). In multivariate analysis, CIMT (β = .34, P < .001) and age (β = .11, P < .019) were independently associated with SXscore. We have demonstrated a significant relation between CIMT and SXscore. Although this study is correlative and no causative conclusions can be drawn, our findings suggest that increased CIMT could reflect complex coronary artery lesions.     

Epicardial mass causing cardiac compression: an unusual involvement in lymphomatoid granulomatosis

Lymphomatoid granulomatosis is a rare, diffuse, large B-cell lymphoma that is positive for Epstein-Barr virus. A multiorgan process, it manifests itself chiefly in the lungs but can also affect the skin, nervous system, and kidneys. Cardiac involvement and pericardial effusion are very unusual. We report the case of a 62-year-old man with lymphomatoid granulomatosis involving the heart and lungs. Diagnosis was confirmed with wedge biopsy at pericardiotomy, and the patient was treated with cyclophosphamide, prednisolone, and vincristine. Although the patient was still symptomatic at 6-month follow-up, he was in partial remission with improved functional capacity.