Oxidative metabolism of lung macrophages exposed to sodium arsenite

Arsenic pollution has become increasingly severe. It occurs as the result of geological processes and different human activities. Arsenic toxicity at the respiratory level occurs mainly by inhalation of products of coal combustion. The aim of this study was to evaluate sodium arsenite (As³⁺) toxicity in murine alveolar macrophages (AMs) in vitro and its association with the alterations in cell metabolism.

No changes in viability, apoptosis or cell area were detected in AMs treated with As³⁺ concentrations up to 2 μM for 24–96 h. A marked decrease in these end-points was observed for As³⁺ concentrations ranging from 2.5 μM to 10 μM.

Regarding the dynamics of the endo-exocytic process triggered by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cell incorporation, no variations were detected for As³⁺ concentrations lower than 2 μM while higher concentrations markedly modified this response.

MTT specific activity, as a measure of cell metabolic activity, was not modified irrespective of the As³⁺ concentration assayed. However, nitroblue tetrazolium (NBT) specific activity, as a measure of superoxide anion generation, is responsive but only to low As³⁺ doses.

Although this study focuses on lung macrophages, the effects of As³⁺ described herein may also apply to the response of macrophages residing in other organs.

Arsenite modifies the metabolic and the oxidative status of AMs in vitro. When macrophages are in an As³⁺ rich medium, they exhibit a reduction in respiratory burst levels and lose their intrinsic capacity to respond to toxicants.     

Castleman disease: surgical cure in pediatric patients

Castleman disease is a rare disorder characterized by lymphoid hyperplasia which rarely manifests in children. We present 2 cases which highlight both histologic variants of this disease, and provide suggestions regarding workup and treatment with the goal of making practitioners aware of Castleman disease in the differential diagnosis of a child presenting with vague symptoms.     

Prospective study of short stature and newly diagnosed asthma in women.

The authors tested the hypothesis that short stature predicts adult-onset asthma independent of obesity among women in the Nurses' Health Study. Height, weight, and physician-diagnosed asthma were assessed with validated questionnaire items. Proportional hazard models adjusted separately for weight and body mass index. The rate of newly diagnosed asthma was 1.55 times greater in the shortest versus the tallest quintile after adjustment for weight (95% CI, 1.26-1.91). After adjustment for body mass index, the rate ratio was 1.16 (95% CI, 0.94-1.42). Short stature predicted adult-onset asthma in a large cohort of women, but this association was not independent of obesity.     

Childhood abuse history and risk behaviors among teen parents in a culturally rooted, couple-focused HIV prevention program.

Pregnant and parenting adolescents living in inner cities are at risk for acquiring HIV through unprotected sexual activity. In addition to individual risk behaviors, a lack of socioeconomic and other environmental resources create risk environments that make certain communities vulnerable to both adolescent pregnancy and HIV/AIDS. Research indicates that adolescent parents, many who have histories of childhood trauma, may use their experience of young parenthood and the concomitant feelings of parental protectiveness as a source of renewed hope for their future. The purpose of this report is to explore the relationship between history of childhood abuse and high risk behaviors in adolescent Latino mothers and fathers enrolled in a randomized clinical trial of a culturally rooted, couple-focused HIV prevention program. In addition, this report describes the HIV prevention program that was designed specifically for young Latino parents wherein maternal and paternal protectiveness are viewed as intrinsic and developing critical factors that promote resiliency and motivate behavioral change.     

Visual acuity results in school-aged children and adults: Lea Symbols chart versus Bailey-Lovie chart.

PURPOSE: To compare visual acuity results obtained using the Lea Symbols chart with visual acuity results obtained with the Bailey-Lovie chart in school-aged children and adults using a within-subjects comparison of monocular acuity results. METHODS: Subjects were 62 individuals between 4.5 and 60 years of age, recruited from patients seen in five optometry clinics. Each subject had acuity of the right eye and the left eye tested with the Lea Symbols chart and the Bailey-Lovie chart, with order of testing varied across subjects. Outcome measures were monocular logarithm of the minimum angle of resolution (logMAR) visual acuity and inter-eye acuity difference in logMAR units for each test. RESULTS: Correlation between acuity results obtained with the two charts was high. There was no difference in absolute inter-eye acuity difference measured with the two acuity charts. However, on average, Lea Symbols acuity scores were one logMAR line better than Bailey-Lovie acuity scores, and this difference increased with worse visual acuity. CONCLUSIONS: The Lea Symbols chart provides a measure of inter-eye difference that is similar to that obtained with the Bailey-Lovie chart. However, the monocular acuity results obtained with the Lea Symbols chart differ from those obtained with the Bailey-Lovie chart, and the difference is dependent on the individual's absolute level of visual acuity.     

Compromised late-stage motion processing in schizophrenia.

BACKGROUND: Visual motion processing is compromised in schizophrenia, as shown in deficient velocity discrimination. Processing of motion signals comprises progressive stages along the geniculate-striate-extrastriate-cortex pathway. Based on neurophysiologic and brain lesion studies, a velocity discrimination deficit can implicate early-stage motion processing if it is contrast-dependent or late-stage motion processing if it is contrast-independent. METHODS: To determine which stage underlies the deficient velocity discrimination in schizophrenia, we examined the effects of visual contrast on velocity discrimination. We measured velocity discrimination thresholds in schizophrenia patients (n = 34) and normal control subjects (n = 17) at both low and high contrasts, using each subject's contrast detection threshold to equate contrast levels. RESULTS: Schizophrenia patients showed poor velocity discrimination that improved little with high contrast, whereas normal control subjects showed enhanced velocity discrimination with increased contrast. CONCLUSIONS: The finding that the velocity discrimination deficit in schizophrenia is independent of contrast modulation implicates the later, rather than the earlier, stages of motion processing, which is mediated in the extrastriate cortex.