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Background: Adiposity-related ventilatory constraints in older adults can potentially contribute to greater risk of exercise intolerance and mobility disability. This study investigated whether ventilatory limitation, measured by breathing reserve (BR) at peak exercise, is associated with body composition and physical function in older adults with obesity.Methods: This study was a cross-sectional analysis of data from a community-based cohort (N = 177) of older men and women (65-79 years) with obesity (body mass index = 30-45 kg/m2). All participants underwent cardiopulmonary exercise testing on a treadmill, dual-energy X-ray absorptiometry for body composition, and physical function assessments. We examined relationships between BR and body composition and physical function using multiple linear regression and compared a subset with (BR ≤ 30%; BR-low; n = 56) and without (BR ≥ 45%; BR-high, n = 48) ventilatory limitation using unpaired Student's t test and analysis of covariance.Results: BR was inversely related to total body mass, lean mass, fat mass, % body fat, and waist circumference (p < 0.05 for all). BR was positively related to 400 m walk time (p = .006) and inversely related to usual gait speed (p = .05) and VO2peak (p < .0001), indicative of worse physical function. BR-low had greater adiposity, but also greater lean mass, higher VO2peak, and faster 400 m walk time, compared to BR-high (p < .05, for all).Conclusions: Older adults with obesity who also have ventilatory limitation have overall higher measures of adiposity, but do not have lower peak exercise capacity or physical function. Thus, ventilatory limitation does not appear to be a contributing factor to obesity-related decrements in exercise tolerance or mobility. [ABSTRACT FROM AUTHOR]

Background. Emergence of human immunodeficiency virus type 1 (HIV-1) drug resistance may limit the benefits of antiretroviral therapy in resource-limited settings. The prevalence of resistance was assessed among patients from KwaZulu Natal, South Africa, following failure of their first highly active antiretroviral therapy (HAART) regimen. Methods. Genotypic resistance testing was performed on plasma virus samples from patients who experienced virologic failure of their first HAART regimen at 2 clinics in KwaZulu Natal. Clinical and demographic data were obtained from medical records. Regression analysis was performed to determine factors associated with ≥1 significant drug resistance mutation. Results. From January 2005 through August 2006, a total of 124 antiretroviral-treated adults who experienced virologic failure were enrolled. The predominant subtype was HIV-1C. Virus samples from 83.5% of participants carried ≥1 significant drug resistance mutation. Dual-class drug-resistant virus was present in 64.3% of participants, and 2.6% had virus with triple-class drug resistance. The most common mutation was M184V/I (64.3% of patients); K103N was present in virus from 51.3%, and V106M was present in virus from 19.1%. Thymidine analog resistance mutations were found in virus from 32.2% of patients, and protease resistance mutations were found in virus from 4.4%. Conclusions. Antiretroviral drug-resistant virus was detected in >80% of South African patients who experienced failure of a first HAART regimen. Patterns of drug resistance reflected drugs used in first-line regimens and viral subtype. Continued surveillance of resistance patterns is warranted to guide selection of second-line regimens. [ABSTRACT FROM AUTHOR]

The treatment of concurrent HIV and tuberculosis (TB) in children <3 years of age has not been well-studied and is complicated by potential drug–drug interactions. The recommended antiretroviral therapy (ART) in coinfected children in South Africa consists of full-strength ritonavir, lamivudine and stavudine. We report on a child initiated on this regimen, during concurrent TB treatment, who promptly developed an adverse reaction, virologic failure and dual-class antiretroviral drug resistance, compromising subsequent salvage ART. [ABSTRACT FROM PUBLISHER]

Objectives: To assess the efficacy of a new screening protocol for critical congenital heart disease (CCHD). Background: In March 2014, the Ontario Provincial Council for Maternal Child Health (PCMCH) recommended screening for CCHD, utilizing pulse oximetry to measure oxygen saturation as part of the newborn examination. However, this is yet to be implemented in all hospitals. Method: An audit of consecutive healthy normal newborn patients in a secondary level centre in Ontario with early adoption of the screening recommendation over a 1-year period was undertaken. Results: The median age of screening was 25 hours (6 to 80 hours). Compliance was 88% (95% if one excludes deliveries by a midwife as they did not agree to comply). Four patients screened positive and were seen by a paediatrician in consultation but did not have CCHD (specificity 99.4%). Conclusions: The current study shows that screening was successfully implemented in a Canadian hospital, with high specificity (99.4%) and good compliance (88%). Reasons for non-acceptance of screening by midwives need to be addressed. [ABSTRACT FROM AUTHOR]

The article focuses on the case of female infant aged 25 weeks with apneic spells. During the infant's stay at a tertiary-level neonatal intensive care unit (NICU), the patient encountered issues including prematurity, respiratory distress syndrome, chronic lung disease and patent ductus arteriosis among others. To prevent and treat neonatal chronic lung disease (CLD), the patient received postnatal corticosteroids and after seven days, dexamethasone proved to have decrease the rate of CLD.

A safe and effective HIV-1 vaccine is urgently needed to control the worldwide AIDS epidemic. Traditional methods of vaccine development have been frustratingly slow, and it is becoming increasingly apparent that radical new approaches may be required. Computational and mathematical approaches, combined with evolutionary reasoning, may provide new insights for the design of an efficacious AIDS vaccine. Here, we used codon-based substitution models and maximum-likelihood (ML) methods to identify positively selected sites that are likely to be involved in the immune control of HIV-1. Analysis of subtypes B and C revealed widespread adaptive evolution. Positively selected amino acids were detected in all nine HIV-1 proteins, including Env. Of particular interest was the high level of positive selection within the C-terminal regions of the immediate-early regulatory proteins, Tat and Rev. Many of the amino acid replacements were associated with the emergence of novel (or alternative) myristylation and casein kinase II (CKII) phosphorylation sites. The impact of these changes on the conformation and antigenicity of Tat and Rev remains to be established. In rhesus macaques, a single CTL-associated amino substitution in Tat has been linked to escape from acute SIV infection. Understanding the relationship between host-driven positive selection and antigenic variation may lead to the development of novel vaccine strategies that preempt the escape process. [ABSTRACT FROM AUTHOR]