Patient perspectives on improving oral health-care practices among people living with HIV/AIDS

This qualitative study explored the impact on oral health-care knowledge, attitudes, and practices among 39 people living with HIV/AIDS (PLWHA) participating in a national initiative aimed at increasing access to oral health care. Personal values and childhood dental experiences, beliefs about the importance of oral health in relation to HIV health, and concerns for appearance and self-esteem were found to be determinants of oral health knowledge and practice. Program participation resulted in better hygiene practices, improved self-esteem and appearance, relief of pain, and better physical and emotional health. In-depth exploration of the causes for these changes revealed a desire to continue with dental care due to the dental staff and environmental setting, and a desire to maintain overall HIV health, including oral health. Our findings emphasize the importance of addressing both personal values and contextual factors in providing oral health-care services to PLWHA.     

Analysis of multiple exposures in the case-crossover design via sparse conditional likelihood

We adapt the least absolute shrinkage and selection operator (lasso) and other sparse methods (elastic net and bootstrapped versions of lasso) to the conditional logistic regression model and provide a full R implementation. These variable selection procedures are applied in the context of case‐crossover studies. We study the performances of conventional and sparse modelling strategies by simulations, then empirically compare results of these methods on the analysis of the association between exposure to medicinal drugs and the risk of causing an injurious road traffic crash in elderly drivers. Controlling the false discovery rate of lasso‐type methods is still problematic, but this problem is also present in conventional methods. The sparse methods have the ability to provide a global analysis of dependencies, and we conclude that some of the variants compared here are valuable tools in the context of case‐crossover studies with a large number of variables. Copyright © 2012 John Wiley & Sons, Ltd.     

Serum erythropoietin in chronic lymphocytic leukaemia

Anaemia is a frequent complication of advanced chronic lymphocytic leukaemia (CLL) and several cytokines known to inhibit erythropoietin (Epo) formation are produced by CLL B cells. Therefore we measured serum Epo levels in 47 CLL patients to determine whether Epo was a significant factor in the development of their anaemia. Epo levels were increased compared to normal individuals and this elevation appeared adequate for the degree of anaemia. The slope of the regression of Epo versus haemoglobin (Hb) was similar to that of a reference group. Serum transferrin receptor (sTfR) levels were also appropriately elevated for the degree of anaemia and correlated with serum Epo. Advanced stage was not associated with reduction of Epo production but diminished erythropoietic activity was observed in several patients. The results indicate that anaemia in CLL is not characterized by inadequate Epo production.     

Induction of endothelial cell apoptosis by heat-shock protein 60-reactive antibodies from anti-endothelial cell autoantibody-positive systemic lupus erythematosus patients

OBJECTIVE: To determine whether anti-endothelial cell autoantibodies (AECAs) from systemic lupus erythematosus (SLE) patients with the antiphospholipid syndrome are involved in the initial endothelial cell (EC) membrane perturbation effect that is postulated to provide a target for antiphospholipid antibody (aPL) binding and, hence, to trigger the thrombotic cascade. To identify the AECA antigenic target on ECs and to determine the mechanism whereby the EC membrane is disrupted. METHODS: AECAs from SLE patients were assayed for binding to ECs by flow cytometry. Positive AECAs were assayed by immunoblotting, and a consensus antigen was identified by mass spectrometry. This candidate antigen was tested in recombinant form for AECA recognition. AECAs were affinity-purified on this antigen and incubated with ECs to determine their physiologic effects. Anti-Hsp60 antibody titers were determined by enzyme-linked immunosorbent assay. The relationship of anti-Hsp60 status and lupus anticoagulant (LAC) status to thrombotic manifestations between disease onset and the last followup visit were analyzed. RESULTS: Most of the SLE sera (73%) possessed IgG that bound to the surface of ECs. These positive IgG shared reactivity against a 60-kd EC surface polypeptide that was identified as human Hsp60. The presence of Hsp60 at the EC surface was established using anti-Hsp60 antibodies from commercial sources or affinity-purified from SLE sera that bound ECs. Incubation of ECs with these anti-Hsp60 antibodies induced apoptosis in a time- and dose-dependent manner, as determined by Hoechst 33342 dye staining of condensed nuclei and by annexin V binding to surface phosphatidylserine. Anti-Hsp60 antibodies were not restricted to SLE patients, but were found in patients with other autoimmune diseases. However, anti-Hsp60 antibodies were significantly associated with an increased frequency of thrombosis when present in combination with LAC in the SLE patients. CONCLUSION: The presence of Hsp60 at the surface of ECs serves as a target for the anti-Hsp60 antibodies in SLE sera. These anti-Hsp60 antibodies bind to ECs and induce apoptosis, particularly phosphatidylserine exposure, thus providing a target for the binding of aPL and inducing the subsequent thrombotic cascade.     

A transgenic mouse with a deletion in the collagenous domain of adiponectin displays elevated circulating adiponectin and improved insulin sensitivity

Adiponectin is a plasma protein expressed exclusively in adipose tissue. Adiponectin levels are linked to insulin sensitivity, but a direct effect of chronically elevated adiponectin on improved insulin sensitivity has not yet been demonstrated. We identified a dominant mutation in the collagenous domain of adiponectin that elevated circulating adiponectin values in mice by 3-fold. Adiponectinemia raised lipid clearance and lipoprotein lipase activity, and suppressed insulin-mediated endogenous glucose production. The induction of adiponectin during puberty and the sexual dimorphism in adult adiponectin values were preserved in these transgenic animals. As a result of elevated adiponectin, serum PRL values and brown adipose mass both increased. The effects on carbohydrate and lipid metabolism were associated with elevated phosphorylation of 5'-AMP-activated protein kinase in liver and elevated expression of peroxisomal proliferator-activated receptor gamma2, caveolin-1, and mitochondrial markers in white adipose tissue. These studies strongly suggest that increasing endogenous adiponectin levels has direct effects on insulin sensitivity and may induce similar physiological responses as prolonged treatment with peroxisomal proliferator-activated receptor gamma agonists.     

Escherichia coli RNA-Polymerase Binding Sites on DNA Are Only 14 Base Pairs Long and Are Located between Sequences That Are Very Rich in A+T

E. coli DNA-dependent RNA-polymerase binding sites on DNAs of T5, T7, and lambda coliphages have been isolated according to three different methods in order to analyze the binding sites themselves as well as the nearest neighboring regions. It is shown that the binding sites are regions that are rather rich in G+C, are about 14 base pairs long and are located between DNA sequences highly enriched in A+T. The biological implications of this result are discussed.     

Reliability of the 400-m usual-pace walk test as an assessment of mobility limitation in older adults

OBJECTIVES: To assess the test-retest reliability of the 400-m usual-pace walk test (400-MWT), and to determine whether the 4-m walk test predicts inability to walk 400 m. DESIGN: Observational. SETTING: Community, 20-m tract course. PARTICIPANTS: Sixty study participants (aged>or=65) were enrolled from the community and met the following eligibility criteria: self-reported difficulty in two or more of four functional domains (mobility and exercise tolerance, upper extremity function, basic self-care, higher functional tasks of independent living) and a score of 18 or higher on the Mini-Mental State Examination. METHODS: The 400-MWT and 4-m walk test were each repeated within 7 days. RESULTS: The mean age+/-standard deviation of the study population was 84.3+/-6.3; 88.3% were women. Nineteen participants (31.7%) failed both 400-MWTs, and 41 successfully completed both tests (kappa=1). Mean walking speed for the 4-m test was 0.87+/-0.18 m/s for those who completed the 400-MWT and 0.53+/-0.17 m/s for those who failed (P<.001). The Spearman correlation coefficient between 4-m and 400-m walking speeds was 0.93. The estimated area under the receiver operating characteristic curve between 4-m walking speed and the ability to perform the 400-MWT was 0.91. The 4-m gait speed averaged less than 0.6 m/s in 80% of subjects who failed the 400-MWT. CONCLUSION: The test-retest reliability for inability to complete the 400-MWT is high. Four-m walking speed is highly predictive of ability to perform the 400-MWT. These findings may prove useful to future clinical trials and observational studies that involve assessment of mobility limitations in older adults.     

Effect of exercise training on respiratory muscle oxygenation in children with congenital heart disease.

BACKGROUND: Diminished aerobic capacity and weakness of both respiratory and peripheral muscles have been observed in cardiac patients and may contribute to exercise limitation. The aim of this study was to evaluate the effects of a home-based training programme on aerobic fitness and oxygenation of the respiratory muscles in children with congenital heart disease (CHD). METHODS AND RESULTS: Eighteen patients with CHD aged 12-15 years participated in this study. Ten patients (training group, TG) underwent a training programme for 12 weeks and eight patients served as a non-training control group (CG). All subjects performed a cardiopulmonary exercise test before and after the study period. Oxygenation of the respiratory muscles was assessed using near-infrared spectroscopy. No significant differences were observed, at baseline and after the completion of the study, between the CG and TG in peak exercise workload, oxygen uptake (VO2), carbon dioxide output (VCO2), pulmonary ventilation (VE), and heart rate (HR). However, a significant improvement in exercise performance was found in the TG versus the CG when results were compared at the ventilatory threshold (Vth): workload (45.2+/-8.0 versus 58.5+/-7.4%; P<0.05), VO2 (62.3+/-7.5 versus 69.8+/-5.1%; P<0.05), VCO2 (49.8+/-5.7 versus 60.0+/-5.8%; P<0.05), VE (42.8+/-9.9 versus 50.1+/-9.5%; P<0.05), and HR (69.5+/-6.1 versus 76.0+/-3.5%; P<0.05). After training, an improvement in oxygenation of the respiratory muscles was found in the TG from 60% of VO2max until the end of exercise. At the Vth, the TG showed greater oxygenation after training (55.1+/-6.6 versus 43.0+/-6.9%, P<0.01, respectively). Furthermore, we showed a significant correlation of the change in respiratory muscle oxygenation and VO2 in the TG (r=0.90, P<0.01). CONCLUSION: It is concluded that general physical training at submaximal intensity induces better aerobic fitness and improves respiratory muscle oxygenation in children with CHD.     

Transradial approach for percutaneous transluminal angioplasty and stenting in the treatment of chronic mesenteric ischemia.

Chronic mesenteric ischemia (CMI) occurs in the presence of slowly progressive, long-standing stenoses of the visceral arteries secondary to atherosclerosis. Angioplasty and stenting are emerging as therapeutic alternatives to surgery in treating CMI. The transradial approach is an attractive alternative access for performing stenting in CMI at improved safety and ease. A case of CMI treated with stenting of the visceral arteries by both transradial and femoral approaches is presented here. The main difficulty in accessing the celiac and mesenteric arteries through the femoral approach is the angle between the aorta and these vessels, which often leads the operator to use multiple catheters. The main advantage of the radial approach (as well as the brachial one) is that it allows easy coaxial alignment of the catheter with the artery. The main problem is the inadequate length of the currently available catheters. The radial approach eliminates the risk for vascular complications and permits early ambulation.