Neurocutaneous melanomatosis with a rapidly deteriorating course

Neurocutaneous melanosis is a rare congenital syndrome characterized by large or multiple congenital melanocytic nevi and benign or malignant pigment cell tumors of the leptomeninges. The prognosis is extremely poor for symptomatic patients, even in the absence of malignant melanoma. We present serial MR imaging findings in the brain and spine of a child with congenital giant hairy nevi who developed progressive leptomeningeal melanomatosis and whose neurologic condition rapidly deteriorated.     

Beta-amyloid peptide potentiates inflammatory responses induced by lipopolysaccharide,interferon -gamma and 'advanced glycation endproducts' in a murine microglia cell line

beta-Amyloid (Abeta) plaques are characteristic hallmarks of Alzheimer's disease (AD). In AD, it has been suggested that activation of microglial cells might be the link between Abeta deposition and neuronal degeneration. Activated microglia are associated with senile plaques and produce free radicals and inflammatory cytokines. However, it is still not clear whether Abeta needs a prestimulated environment to exert its proinflammatory potential. Advanced glycation endproducts (AGEs), protein-bound oxidation products of sugars, have been shown to accumulate in senile plaques and could induce a silent but chronic inflammation in the AD brain. We tested whether Abeta acts as an amplifier of a submaximal proinflammatory response initiated by exposure to chicken egg albumin-AGE, lipopolysaccharide or interferon-gamma. Synthetic Abeta was used to produce three different samples (Abeta-fibrilar; Abeta-aggregated; Abeta-AGE), which were characterized for beta-sheeted fibrils by the thioflavin-T test and electron microscopy. As markers of microglial activation, nitric oxide, interleukin-6, macrophage-colony stimulation factor and tumour necrosis factor-alpha production was measured. All three Abeta samples alone could not induce a detectable microglial response. The combination of Abeta preparations, however, with the coinducers provoked a strong microglial response, whereby Abeta-AGE and fibrilar Abeta were more potent inflammatory signals than aggregated Abeta. Thus, Abeta in senile plaques can amplify microglial activation by a coexisting submaximal inflammatory stimulus. Hence, anti-inflammatory therapeutics could either target the primary proinflammatory signal (e.g. by limiting AGE-formation by AGE inhibitors or cross-link breakers) or the amplifyer Abeta (e.g. by limiting Abeta production by beta- or gamma-secretase inhibitors).     

Doctor Competence and the Demand for Healthcare: Evidence from Rural China

The agency problem between patients and doctors has long been emphasised in the health economics literature, but the empirical evidence on whether patients can evaluate and respond to better quality care remains mixed and inconclusive. Using household data linked to an assessment of village doctors' clinical competence in rural China, we show that there is no correlation between doctor competence and patients' healthcare utilisation, with confidence intervals reasonably tight around zero. Household perceptions of quality are an important determinant of care‐seeking behaviour, yet patients appear unable to recognise more competent doctors – there is no relationship between doctor competence and perceptions of quality. Copyright © 2016 John Wiley & Sons, Ltd.     

Prevalence of atrial fibrillation in US nursing homes: results from the National Nursing Home Survey, 1985-2004

ObjectivesTo evaluate the prevalence of atrial fibrillation (AFib) in US nursing homes from 1985 to 2004 and to project the prevalence of AFib to 2030.DesignThis study is an analysis of cross-sectional data from the US National Nursing Home Survey, years 1985, 1995, 1997, 1999, and 2004.SettingRandomly selected long term care facilities in the United States licensed by the state or certified for Medicaid/Medicare reimbursement.ParticipantsRandomly selected residents within study facilities.MeasurementsNational Nursing Home Survey demographics and current medical conditions data were analyzed. Population estimates were calculated using National Nursing Home Survey sample weights. Absolute observed annual linear growth of the AFib prevalence rate was calculated using linear regression. Predictive margins were estimated using logistic regression models to evaluate effect of changes in resident case-mix over the survey years. Three estimation methods predicted the number residents having AFib in 2030.ResultsThe sample sizes of surveyed resident groups were as follows: n = 5238 (1985); n = 8056 (1995); n = 8138 (1997); n = 8215 (1999); and n = 13,507 (2004). Prevalence rates of AFib by year were 2.8% (95% confidence interval [CI]: 2.3–3.4%; 1985), 5.1% (95% CI: 4.6–5.6%; 1995), 5.8% (95% CI: 5.3–6.3%; 1997), 6.9% (95% CI: 6.3–7.4%; 1999), and 10.9% (95% CI: 10.2–11.5%; 2004). Population estimates of nursing home residents with AFib (in thousands) were 42.2 (95% CI: 34.1–50.3; 1985), 78.7 (95% CI: 70.8–86.7; 1995), 93.6 (95% CI: 84.9–102.3; 1997), 111.8 (95% CI: 102.1–121.5; 1999), and 162.1 (95% CI: 152.4–171.7; 2004). Absolute annual linear growth in the prevalence rate of AFib was +0.38% observed (P = .022), +0.39% using unadjusted predictive margins (P = .007), and +0.37% using adjusted predictive margins (P = .007). Projected estimates showed that 272,000 (95% CI: 197,000–347,000), 300,000, or 325,000 residents would have AFib in the year 2030.ConclusionThe prevalence of AFib in US nursing home residents increased from 1985 to 2004 and is projected to grow substantially over the next 20 years, potentially resulting in an increased nursing home staff burden owing to increased stroke risk evaluations.     

Determining human immunodeficiency virus coreceptor use in a clinical setting: degree of correlation between two phenotypic assays and a bioinformatic model

Two recombinant phenotypic assays for human immunodeficiency virus (HIV) coreceptor usage and an HIV envelope genotypic predictor were employed on a set of clinically derived HIV type 1 (HIV-1) samples in order to evaluate the concordance between measures. Previously genotyped HIV-1 samples derived from antiretroviral-na?ve individuals were tested for coreceptor usage using two independent phenotyping methods. Phenotypes were determined by validated recombinant assays that incorporate either an approximately 2,500-bp ("Trofile" assay) or an approximately 900-bp (TRT assay) fragment of the HIV envelope gp120. Population-based HIV envelope V3 loop sequences ( approximately 105 bp) were derived by automated sequence analysis. Genotypic coreceptor predictions were performed using a support vector machine model trained on a separate genotype-Trofile phenotype data set. HIV coreceptor usage was obtained from both phenotypic assays for 74 samples, with an overall 85.1% concordance. There was no evidence of a difference in sensitivity between the two phenotypic assays. A bioinformatic algorithm based on a support vector machine using HIV V3 genotype data was able to achieve 86.5% and 79.7% concordance with the Trofile and TRT assays, respectively, approaching the degree of agreement between the two phenotype assays. In most cases, the phenotype assays and the bioinformatic approach gave similar results. However, in cases where there were differences in the tropism results, it was not clear which of the assays was "correct." X4 (CXCR4-using) minority species in clinically derived samples likely complicate the interpretation of both phenotypic and genotypic assessments of HIV tropism.     

Growth hormone resistance in uremia

Growth retardation is a major complication in children with uremia. Protein restriction, calorie deficit, metabolic acidosis, renal osteodystrophy, and endocrinologic disturbances contribute to the growth failure. The effect of these factors on growth retardation can be attenuated in part by therapy with vitamin D metabolites, adequate nutrition, alkalization, and dialysis. Linear growth in children with uremia is markedly retarded despite normal or increased levels of circulating serum growth hormone. An increased growth hormone level in children with uremia is due to normal growth hormone secretion from the pituitary gland and impaired growth hormone clearance in the kidney. However, the elevated growth hormone level does not lead to a commensurate rise in serum insulin-like growth factor I (IGF-I); the serum IGF-I level is decreased or normal in relation to the degree of renal failure. This discrepancy suggests growth hormone resistance in the liver in uremia. Recent molecular techniques open a new era in studying the gene expression for growth hormone or IGF-I. There is no doubt today that growth hormone treatment has the beneficial effect of growth promotion in children with uremia, which also suggests endogenous growth hormone resistance in target organs or target cells in uremia.     

Pulmonary sequelae in long-term survivors of bronchopulmonary dysplasia

BACKGROUND: Bronchopulmonary dysplasia (BPD) is a common problem in premature babies. Long-term sequelae are the main concerns. METHODS: A retrospective review of all BPD children born in Queen Mary Hospital, a teaching hospital of the University of Hong Kong, from January 1987 to December 1995 was conducted. Children with cerebral palsy, immunodeficiency, congenital heart disorders, renal or liver failure were excluded from analysis. Chest radiography (CXR), electrocardiogram (ECG) and pulse oximetry were routinely performed. RESULTS: Fifty-five children completed the study. The female to male ratio was 1:1.1. The mean gestational age was 28 weeks. Twenty-five children were born with a birthweight of less than 1001 g. Mean age at assessment was 5.4 years. Twenty-four children (44%) demonstrated signs or symptoms of current asthma. Only seven children managed to perform the spirometry satisfactorily. One child had low forced vital capacity and one had hyperresponsive airway. The only risk factor found to be associated with current asthma was the birth month, with those children born early in the year at higher risk of developing current asthma. Seventeen of 48 children (35%) had a bodyweight below the third percentile at the corrected age of 1 year. Eleven of these seventeen children (65%) demonstrated catch-up growth at assessment. Abnormal CXR was found in 25 of 40 children (63%). All had normal pulse oximetry and ECG. CONCLUSIONS: Bronchopulmonary dysplasia children had a significantly higher risk than the general population of developing current asthma (odds ratio 4.7; 95% confidence interval 3.4-6.5; P<0.0001). The importance of birth month suggests that early life experience is important in the pathogenesis of asthma, even in BPD children. The long-term growth of BPD children was much better than previously reported.     

Application of the PRECEDE model to understanding mental health promoting behaviors in Hong Kong.

The burdens related to mental illness have been increasingly recognized in many countries. Nevertheless, research in positive mental health behaviors remains scarce. This study utilizes the Predisposing, Reinforcing, and Enabling Causes in Education Diagnosis and Evaluation (PRECEDE) model to identify factors associated with mental health promoting behaviors and to examine the effects of these behaviors on mental well-being and quality of life among 941 adults in Hong Kong. Structural equation modeling shows that sense of coherence (predisposing factor), social support (reinforcing factor), and daily hassles (enabling factor) are significantly related to mental health promoting behaviors, which are associated with mental well-being and quality of life. Results of bootstrap analyses confirm the mediating role of mental health promoting behaviors on well-being and quality of life. The study supports the application of the PRECEDE model in understanding mental health promoting behaviors and demonstrates its relationships with well-being and quality of life.