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Background. Data on iron and vitamin A deficiency are scarce in school-aged children living with HIV (HIV+) compared with children without HIV (HIV--). Both deficiencies can contribute to anaemia. Objective. To assess anaemia, iron and vitamin A status in a sample of HIV+ and HIV-- school-aged children in South Africa. Methods. In this comparative cross-sectional study, biomarkers for anaemia (haemoglobin), iron (plasma ferritin (PF), soluble transferrin receptor), vitamin A (retinol-binding protein (RBP)) and inflammatory status (C-reactive protein, α-1-acid glycoprotein) were measured in 8 - 13-year-old children from Cape Town living with (n=143) and without HIV (n=148). Measurements of PF and RBP were adjusted for inflammation using a regression-correction approach. Results. HIV+ children had higher prevalences of anaemia (29% v. 14%; odds ratio (OR) = 2.6; 95% confidence interval (CI) 1.4 - 4.9; p=0.002), iron-deficient erythropoiesis (20% v. 9%; OR=2.5; 95% CI 1.2 - 5.0; p=0.013) and iron deficiency anaemia (11% v. 4%; OR=2.9; 95% CI 1.1 - 7.7; p=0.035) than HIV-- children. Marginal vitamin A deficiency was noted in 52% of HIV+ and 57% of HIV-- children (p=0.711). Subclinical inflammation was more prevalent in HIV+ than HIV-- children (p=0.012). Conclusion. Anaemia, iron-deficient erythropoiesis and iron deficiency anaemia were more prevalent in HIV+ than HIV-- children. Prevalence of marginal vitamin A deficiency was high in both groups. Efforts to improve micronutrient status and mitigate nutritional determinants of anaemia in HIV+ children from resource-limited settings should be prioritised. [ABSTRACT FROM AUTHOR]

Background. Exclusive breastfeeding during the first 6 months of life protects against infant morbidity and mortality. Few studies describe the infant feeding practices of mothers living in low-income areas of the Western Cape Province of South Africa (SA). Objective. To describe the infant feeding practices of mothers of infants younger than 6 months in two low-income communities of SA. Methods. A cross-sectional community-based study using a structured questionnaire, and seven focus group discussions were conducted from February to August 2011 in Avian Park and Zwelethemba in Worcester, an urban area in the Western Cape. Results. Seventy-seven per cent of participants (n=108) had initiated breastfeeding. At the time of the study, 6% (n=8) breastfed exclusively. Ninety-four per cent (n=132) applied suboptimal breastfeeding practices: 36% (n=51) breastfed predominantly, 27% (n=38) breastfed partially and 31% (n=43) did not breastfeed. Ninety per cent (n=126) of the mothers had introduced water, of whom 83% (n=104) had done so before their infants were 1 month old. Forty-four per cent (n=61) of the mothers had introduced food or formula milk, of whom 75% (n=46) had done so before their infants were 3 months old. Qualitative findings indicated that gripe water, Lennon's Behoedmiddel and herbal medicines were also given to infants. Nutritive liquids and/or food most commonly given as supplementary feeds were formula milk and commercial infant cereal. Conclusion. Exclusive breastfeeding (EBF) during the first 6 months of life was a rare practice in these low-income communities. Water, non-prescription medicines and formula milk and/or food were introduced at an early age. [ABSTRACT FROM AUTHOR]

The promotion of exclusive breastfeeding for the first six months of life is estimated to be the most effective measure to save infants from morbidity and mortality in low-income settings. South Africa is challenged by very poor exclusive breastfeeding practices (6.8-8.3%) during the first six months of life. In the low-income area investigated, the exclusive breastfeeding rate was 6% in 2011. The aim of this study was to describe the factors impeding exclusive breastfeeding practices in a low-income area of the Western Cape Province of South Africa in order to provide recommendations on tailored and generalisable intervention strategies for the promotion of exclusive breastfeeding practices. Focus group discussions were conducted with caregivers and health care workers. Several barriers to exclusive breastfeeding practices were reported and seven themes were identified during data analysis: 1) the perception that infants needed water, gripe water and Lennon's Behoedmiddel; 2) the concern that milk alone does not satisfy an infant; 3) inadequate infant feeding education and support by the health system; 4) the lack of community-based postnatal support; 5) convention and family influence; 6) mothers separated from infants; and 7) local beliefs about maternal behaviour and breastfeeding. The barriers to exclusive breastfeeding practices proved to be multifaceted and interlinked. The influence of convention and community perceptions and beliefs combined with suboptimal infant feeding education by the health system and the lack of local postnatal breastfeeding support initiatives posed an intricate group of barriers to exclusive breastfeeding practices. [ABSTRACT FROM AUTHOR]

The purified exo-inulinase enzyme of Aspergillus niger N402 (AngInuE; heterologously expressed in Escherichia coli) displayed a sucrose:inulin (S/I) hydrolysis ratio of 2.3, characteristic for a typical exo-inulinase. The enzyme also had significant transfructosylating activity with increasing sucrose concentrations, producing various oligosaccharides. The AngInuE protein molecular mass was 57 kDa, close to the calculated value for the mature protein. AngInuE thus was active as a monomeric, non-glycosylated protein. Contradictory data on hydrolysis/transfructosylation activity ratios have been published for the (almost) identical (but monomeric or dimeric and glycosylated) exo-inulinases of other aspergilli. Our data clearly show that the AngInuE enzyme, produced in and purified from E. coli, is a broad specificity exo-inulinase that also has significant transfructosylating activity with sucrose. Analysis of site-directed mutants of AngInuE showed that the glycoside hydrolase family 32 conserved domain G is important for catalytic efficiency, with a clear role in hydrolysis of both sucrose and fructans. [ABSTRACT FROM AUTHOR]

Background and aims: In chronic liver disease, bone disease frequently develops. The contributions of the different features of liver disease such as parenchymal inflammation, portal hypertension, and portasystemic shunting on bone metabolism have not been systematically studied. The aim of this study was to identify the features of liver disease contributing to bone disease using rat models. Methods: Parenchymal liver disease was induced by carbon tetrachloride administration, portal hypertension by partial portal vein ligation, and portasystemic shunting by end to side anastomosis of the portal vein to the inferior vena cava. Normal and sham operated surgical animals served as controls. Serum calcium, 25-hydroxy vitamin D (25-OH vit D), and osteocalcin levels, and urinary deoxypyridinoline excretion were analysed. Testosterone and oestradiol levels were determined in male and female rats, respectively. Interleukin 1, interleukin 6, and tumour necrosis factor α (TNF-α) were determined in serum. Bone density was measured in all groups and in addition, in the surgical groups, histomorphometry was performed on undecalcified specimens of the proximal tibia. The calcium content of the femurs, removed at termination and ashed, was determined. Results: Early parenchymal disease and portal hypertension did not affect bone metabolism or body mass. Portasystemic shunting increased bone resorption, decreased bone formation, bone density, and trabecular bone volume which were commensurate with a reduction in body mass. TNF-α levels were elevated and testosterone levels were Iow in male portasystemic shunted rats. Conclusions: Portasystemic shunting in the rat adversely affects bone metabolism as part of a generalised catabolic state where high TNF-α and Iow testosterone and 25-OH vit D levels may play a rope. [ABSTRACT FROM AUTHOR]

Interactions at the behavioral level between dopamine (DA) and opioid receptors in the mammalian brain have been amply demonstrated. Considering the pivotal role for DA receptors in the pharmacotherapy of Parkinson's disease (PD), these interactions might be clinically relevant. Therefore, in the present study the effects of the opioid antagonist naltrexone and agonist morphine on D and D receptor induced stimulation of motor behavior in the unilateral MPTP monkey model ( n=5) of PD were investigated. The results show that both naltrexone and morphine [0.1-1.0 mg/kg; intramuscular injection (IM)] inhibited D receptor stimulated contralateral rotational behavior and hand use induced by administration of quinpirole (LY 171555; 0.01 mg/kg, IM) in a dose-related way. However, no effects of these opioid drugs were observed on D receptor stimulated contralateral rotational behavior and hand use induced by administration of SKF 81297 (0.3 mg/kg, IM). Interestingly, the action of the alleged preferential μ-receptor antagonist naltrexone was mimicked by the selective δ-opioid antagonist naltrindole (0.5 mg/kg, IM). From this study it is concluded that in a non-human primate model of PD, alteration of opioid tonus leads to modulation of D receptor but not D receptor controlled motor behavior. The possible underlying mechanisms and clinical relevance of these findings are discussed. [ABSTRACT FROM AUTHOR]

Relapse into problematic alcohol drinking is a serious problem in the treatment of alcoholism. Free-choice drinking rhesus monkeys show relapse-like behaviour after imposed abstinence of alcohol, by immediately reinitiating ethanol intake at an increased level. The relapse-like behaviour of the monkeys seems not induced by physical withdrawal, but rather argues for a resistance to extinction of ethanol-reinforced behaviour. It has been suggested that endogenous opioids play a role in the positive reinforcing effect of ethanol. In this study, the effect of the opiate antagonist naltrexone was investigated in eight adult male rhesus monkeys (Macaca mulatta) who had about 1 year experience with alcohol drinking, under two conditions: 1) (expt 1) during continuous and concurrent supply of drinking water and two ethanol/water solutions (16% and 32% (v/v)), and 2) (expt 2) after 2 days of alcohol abstinence. In both experiments, each monkey received six doses of naltrexone (0.02, 0.06, 0.17, 0.5, 1.0, 1.5 mg · kg); each dose was paired with a placebo injection (im) in a cross-over design. Consumption was measured from 16.00 hours in the afternoon (30 min after injection) to 9.00 hours the next morning. In experiment 1 naltrexone reduced total net ethanol intake in a graded dose-dependent manner. The effect of naltrexone was apparent shortly after injection, and lasted until the following day. Consumption of drinking water was reduced only shortly after injection. In expt 2, reduction of net ethanol intake was largely restricted to the first few hours of reinitiation of alcohol drinking, i.e. the period in which the abstinence-induced increase was manifest. Consumption of drinking water was not affected by naltrexone. Naltrexone hardly influenced consumption of the non-preferred ethanol solution of 32%. It is postulated that the opioid modulation specifically interacted with positively reinforced behaviour. In expt 2 naltrexone reduced ethanol intake at a lower dose (0.17 mg · kg) compared to expt 1 (0.50 mg · kg), but net ethanol intakes however remained higher. It might be that alcohol abstinence resulted in altered opioid activity, leading to increased ethanol-seeking behaviour. The renewed presentation of ethanol solutions (also) might have stimulated reinitiation of alcohol drinking, representing conditioned incentive stimuli. The reported monkey model of relapse in alcohol drinking could be a useful tool to evaluate new hypotheses and experimental treatments with respect to human alcoholism. [ABSTRACT FROM AUTHOR]

The vasopressin analog desglycinamide-(Arg8)-vasopressin (DGAVP) has been reported to reduce the acquisition of heroin and cocaine self-injection behavior in rats. This led to the hypothesis that DGAVP can reduce the self-administration of psycho-active drugs (including ethanol) by attenuating central reinforcement processes. Under forced ingestion conditions, DGAVP has been reported, however, to enhance alcohol drinking in rats. We studied the effect of DGAVP on the acquisition of voluntary, free-choice alcohol drinking in naive rhesus monkeys, that had concurrent access to either 1% and 2% (n = 12) or to 4% and 8% (n = 8) ethanol/water solutions in addition to drinking water. Half of the monkeys were injected twice per day with 50 μg. kg-1 of DGAVP for 14 successive days, the other half received placebo. Subsequently, all subjects had access to the same solutions for another 14 days without treatment. DGAVP did not significantly affect concentration preference behavior. With regard to net ethanol ingestion in animals drinking 1% and 2% solutions, DGAVP decreased net ethanol intakes, having a time-dependent and long lasting effect; placebo-treated animals gradually increased net ethanol intakes over time. The placebo-treated animals in the 4% and 8% group, showed a different acquisition pattern; DGAVP reduced net ethanol intake in two animals in a similar way as above. Two animals behaved differently. It is concluded that in a free-choice condition DGAVP did not enhance the acquisition of alcohol drinking in monkeys, but rather inhibited ethanol self-administration in the majority of the subjects. [ABSTRACT FROM AUTHOR]