Long-term risk of adverse cardiovascular outcomes associated with cutaneous lupus erythematosus: a nationwide cohort study

Clinical Rheumatology - Autoimmune diseases, including systemic lupus erythematosus, have been associated with a substantial risk of cardiovascular morbidity and mortality. However, data on the...     

An exploratory pilot study on the involvement of APOE,HFE, C9ORF72 variants and comorbidities in neurocognitive and physical performance in a group of HIV-infected people

Metabolic Brain Disease - Cognitive decline of aging is modulated by chronic inflammation and comorbidities. In people with HIV-infection (PWH) it may also be affected by HIV-induced inflammation,...     

Hepatitis C virus kinetics during and immediately after liver transplantation

The study of hepatitis C virus (HCV) kinetics after liver transplantation (LT) might be important to design strategies to prevent HCV infection of the graft. We analyzed HCV kinetics during and immediately after LT in 20 consecutive patients undergoing LT for HCV-related cirrhosis. HCV RNA was quantified in blood samples obtained at regular intervals before, during, and after transplantation. HCV-RNA concentrations decreased in 18 of 20 patients during the anhepatic phase (mean decay slope -0.92, mean HCV elimination half-life 2.2 hours). We found a significant correlation between the HCV viral load decay and the blood loss during the anhepatic phase, indicating that the observed HCV clearance rates are maximum estimates. In fact, in 1 patient with an unusually long anhepatic phase of 20 hours and with minimum blood loss, the HCV elimination half-life was 10.3 hours. Eight to 24 hours after graft reperfusion a sharp decrease in HCV viral load occurred in 19 patients (mean decay slope -0.34, mean HCV elimination half-life 3.44 hours). HCV RNA became undetectable in only 1 patient. During the following days, HCV-RNA concentrations increased rapidly in 10 patients (mean HCV doubling time 13.8 hours), remained at similar levels in 4, and continued to decrease in 6. The only variable associated with a second-phase viral load decay was the absence of corticosteroids as part of the immunosuppressive regimen. In conclusion, a sharp decrease in HCV viral load occurs during the anhepatic phase and immediately after graft reperfusion, most likely owing to a lack of virion production and hepatic viral clearance. HCV infection of the graft, however, is an extremely dynamic process and viral replication begins a few hours after LT.     

Interface connections of a transmembrane voltage sensor

Voltage-sensitive ion channels open and close in response to changes in transmembrane (TM) potential caused by the motion of the S4 voltage sensors. These sensors are alpha-helices that include four or more positively charged amino acids, most commonly arginine. The so-called paddle model, based on the high-resolution structure of the KvAP K+ channel [Jiang, et al. (2003) Nature 423, 33-41], posits that the S4 sensors move within the membrane bilayer in response to TM voltage changes. Direct exposure of S4 sensors to lipid is contrary to the classical expectation that the dielectric contrast between the membrane hydrocarbon core and water presents an insurmountable energetic penalty to burial of electric charges. Nevertheless, recent experiments have shown that a helix with the sequence of KvAP S4 can be inserted across the endoplasmic reticulum membrane. To reconcile this result with the classical energetics argument, we have carried out a molecular dynamics simulation of an isolated TM S4 helix in a lipid bilayer. The simulation reveals a stabilizing hydrogen-bonded network of water and lipid phosphates around the arginines that reduces the effective thickness of the bilayer hydrocarbon core to approximately 10 A in the vicinity of the helix. It suggests that bilayer phospholipids can adapt locally to strongly perturbing protein elements, causing the phospholipids to become a structural extension of the protein.     

Double-blind crossover randomized trial of intravenously administered verapamil. Its use for atrial fibrillation and flutter following open heart surgery

Fourteen patients with onset of atrial fibrillation (11) or flutter (three) and ventricular rate over 120 beats per minute following cardiac surgery were treated with intravenous (IV) doses of verapamil hydrochloride or placebo in a double-blind crossover protocol. Patients with poor left ventricular function, hypotension, atrioventricular block, and taking beta-blockers and disopyramide were excluded. The dosages were 0.075 mg/kg and 0.15 mg/kg given 15 minutes apart, with termination of study on achieving an end point (conversion to sinus rhythm or slowing of ventricular rate to below 100 beats per minute). None reached the end point with placebo but all with verapamil. Baseline ventricular rate was 144 +/- 20 beats per minute, after placebo 143 +/- 16 beats per minute, and after verapamil 89 +/- 7 beats per minute (mean +/- SD). Thus, IV verapamil briefly slows the ventricular rate of atrial tachyarrhythmias following cardiac surgery.     

Differential coupling of m-cholinoceptors to Gi/Go-proteins in failing human myocardium

Muscarinic acetylcholine receptors (mAChRs) mediate their main cardiac effects via pertussis toxin-sensitive G-proteins. Physiological effects differ considerably between atrium and ventricle, and it is unknown to which extent these differences derive from selective receptor-G-protein coupling or further downstream events. We have characterized specific coupling between mAChRs and Gi/Go-protein isoforms in atrial and ventricular myocardium by agonist-dependent photoaffinity labeling with [(32)P]azidoanilido GTP (aaGTP) and immunoprecipitation in sarcolemmal membranes from terminally failing human hearts. The total amount of mAChRs, as determined by specific binding of [(3)H]QNB, was significantly higher in right-atrial (RA +/- SEM, 959 +/- 68 fmol/mg, n = 4) than in left-ventricular membranes (LV, 582 +/- 53 fmol/mg, n = 6). Standardized immunoblots revealed that Gialpha-2 was the predominant subtype in both regions. A 40-kDa splice variant of Goalpha (Goalpha-1 and/or Goalpha-3) was almost exclusively detectable in RA. Levels of Gialpha-3 and a 39-kDa splice variant of Goalpha (Goalpha-2) were also higher in RA. Basal aaGTP binding was higher in RA than in LV for all Gialpha/Goalpha subtypes. The carbachol (10 micromol/l)-induced increase in aaGTP binding was significantly higher in RA than in LV for Goalpha-1/3 (336 +/- 95% of LV, n = 4) and for Gialpha-3 (211 +/- 83%), lower for Gialpha-2 (42 +/- 5%), and was similar in both regions for Goalpha-2 (130 +/- 62%). The differential coupling of mAChRs in human RA and LV suggests that the initiation of different physiological responses to mAChR stimulation starts with signal sorting at the receptor-G-protein level.     

Patient safety culture in out-of-hours primary care services in the Netherlands: a cross-sectional survey

Objective: To examine patient safety culture in Dutch out-of-hours primary care using the safety attitudes questionnaire (SAQ) which includes five factors: teamwork climate, safety climate, job satisfaction, perceptions of management and communication openness.

Design: Cross-sectional observational study using an anonymous web-survey. Setting Sixteen out-of-hours general practitioner (GP) cooperatives and two call centers in the Netherlands. Subjects Primary healthcare providers in out-of-hours services. Main outcome measures Mean scores on patient safety culture factors; association between patient safety culture and profession, gender, age, and working experience.

Results: Overall response rate was 43%. A total of 784 respondents were included; mainly GPs (N?=?470) and triage nurses (N?=?189). The healthcare providers were most positive about teamwork climate and job satisfaction, and less about communication openness and safety climate. The largest variation between clinics was found on safety climate; the lowest on teamwork climate. Triage nurses scored significantly higher than GPs on each of the five patient safety factors. Older healthcare providers scored significantly higher than younger on safety climate and perceptions of management. More working experience was positively related to higher teamwork climate and communication openness. Gender was not associated with any of the patient safety factors.

Conclusions: Our study showed that healthcare providers perceive patient safety culture in Dutch GP cooperatives positively, but there are differences related to the respondents’ profession, age and working experience. Recommendations for future studies are to examine reasons for these differences, to examine the effects of interventions to improve safety culture and to make international comparisons of safety culture.

• Key Points

• Creating a positive patient safety culture is assumed to be a prerequisite for quality and safety. We found that:

• ??healthcare providers in Dutch GP cooperatives perceive patient safety culture positively;

• ??triage nurses scored higher than GPs, and older and more experienced healthcare professionals scored higher than younger and less experienced professionals – on several patient safety culture factors; and

• ??within the GP cooperatives, safety climate and openness of communication had the largest potential for improvement.

     

3-Dimensional Cervical Movement Characteristics and the Influence of Thoracic Treatment on a Subgroup of Acute Neck Pain Patients

Objective

The purpose of this study was to investigate the influence of thoracic high-velocity low-amplitude thrust (HVLAT) manipulation on quantitative and qualitative 3-dimensional cervical spine kinematic patterns in a subgroup of patients with acute neck pain.