Considerations in the nutritional management of patients with acute renal failure

Despite improvements in medical and dialytic therapies, mortality rates for patients with complicated acute renal failure (ARF) remains tragically high-above 50%. Mortality rates also remain persistently high in patients with ARF and preexisting or hospital-acquired malnutrition. ARF causes significant changes in substrate utilization largely because of the metabolic consequences of acute uremia compounded by underlying stress from acute illness. Alterations in protein or amino acid, carbohydrate, and lipid metabolism as well as fluid, electrolyte, and acid-base balance need to be considered when providing nutritional therapy in patients with ARF. Also, the degree of renal impairment, which influences the need for renal replacement therapy (RRT), impacts nutritional requirements. As medical management is becoming highly aggressive in treating ARF with RRT, the ability to provide adequate nutrition is enhanced; however, no consensus on optimal caloric and macro-/micronutrient requirements is available. More current research is required to clarify nutritional needs of this patient population. Nevertheless, individualizing nutrition care and integrating nutritional therapies within a team setting is essential in providing optimal patient care in the presence of ARF.     

Women's sexual self-schema.

Sexual self-schemas are cognitive generalizations about sexual aspects of oneself that are derived from past experience, manifest in current experience, influential in the processing of sexually relevant social information, and guide sexual behavior. In Part 1, a measure of a cognitive self-view of women's sexuality was developed. The construct includes 2 positive aspects, an inclination to experience passionate–romantic emotions and a behavioral openness to sexual experience, and a negative aspect, embarrassment or conservativism, which may be a deterrent to sexual–romantic affects and behaviors. In Part 2, the role of sexual schema in intrapersonal and interpersonal aspects of sexuality was examined. In Part 3, a bivariate model was explored and 4 self-views (positive, co-schematic, aschematic, and negative) were proposed and compared. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The utility of IgA antibody to human immunodeficiency virus type 1 in early diagnosis of vertically transmitted infection. National Institute of Allergy and Infectious Diseases and National Institute of Child Health and Human Development Women and Infants Transmission Study Group

OBJECTIVE: To determine the sensitivity and specificity of anti-human immunodeficiency virus (HIV) IgA in identifying infected infants at or before 6 months of age among the offspring of HIV-infected mothers. DESIGN: Prospective comparison of anti-HIV IgA measurement performed in 2 different laboratories by 2 different methods with the criterion standard of blood culture. SETTING: Five centers in the United States and Puerto Rico. PATIENTS: Population-based sample of 156 infants of HIV-infected mothers in the Women and Infants Transmission Study. MAIN OUTCOME MEASURES: Results of anti-HIV IgA test in relation to the infection status of the infants as measured by blood culture. RESULTS: Six-month plasma or serum samples were first tested in the 2 laboratories. The sensitivity and specificity of anti-HIV IgA in detecting infected infants at this age by laboratories 1 and 2 were 69% and 63% and 100% and 99%, respectively. A look-back study of samples obtained at birth, 1, 2, and 4 months was then performed on all infected children and a matched set of uninfected children. The performance of the test at birth was unsatisfactory in both laboratories (sensitivity 44% and 33%, specificity 43% and 60%), whether peripheral or cord blood was examined. At 1, 2, and 4 months, the sensitivity of the test was lower than at 6 months, but specificity was high. A modest correlation of absent anti-HIV IgA antibody and low percentage of CD4 cells in peripheral blood was seen at 6 months of age. CONCLUSIONS: The anti-HIV IgA test has moderate sensitivity and high specificity for the diagnosis of HIV infection at 6 months of age in the offspring of infected mothers.     

In situ characterization of nitrifying biofilm: Minimizing biomass loss and preserving perspective

Methods for characterizing nitrifying bacteria within biofilms are of key importance to understand and optimize the nitrification kinetics of attached growth treatment facilities. In this work, we propose an analytical protocol based upon environmental scanning electron microscopy (ESEM) and confocal laser scanning microscopy (CSLM) in combination with fluorescent in situ hybridization (FISH) to characterize the structure of nitrifying biofilm as it remains attached to the original reactor substratum. This protocol minimizes the loss of mass and distortion of in situ perspective commonly associated with traditionally applied microscopic techniques and thereby enables a more accurate estimation of the nitrifying biomass within biofilm attached to the substratum. The use of ESEM eliminates the destructive preparatory procedures associated with traditional scanning electron microscopy and thus the loss of mass and shrinking of the samples. ESEM is used in this study to evaluate the percent coverage of the substratum with biofilm and the biofilm thickness. CLSM-FISH is used to determine cell counts in the biofilm and to characterize the undisturbed substratum/biofilm interface. By hybridizing and analyzing the nitrifying biofilm using CLSM as it remains attached to the substratum, the loss of material and distortion of in situ perspective associated with the biofilm detachment process is minimized. Moreover, by conducting the CLSM analysis directly on the nitrifying biofilm as it remains attached to the substratum it is shown that cell counts at the substratum/biofilm interface differ significantly from that located above the interface.     

In vivo measurements of neurotransmitters by microdialysis sampling

The brain contains a vast network of neurons that connect with each other at specialized junctions called synapses.A synapse consists of a presynaptic terminal (the "sending"neuron) and a postsynaptic bouton (the "receiving" neuron)that are separated by a gap of 5-50 nm (Figure 1). Chemicals released into this synaptic gap interact with receptors on the postsynaptic neuron. This leads to intracellular changes in the postsynaptic neuron-for example, an altered membrane potential or gene expression. The chemical signal is terminated by transporter proteins that transfer transmitter molecules across the membrane to the intracellular space (a process known as "reuptake")or enzymes that degrade the transmitter in the vicinity of the synapse (Figure 1). This classical view of neurotransmission might be considered point-to-point or"wired" communication because neurons communicate only with neurons to which they are specifically connected. In addition,neurotransmitters can activate receptors at more distant sites either by escaping the synapse or by being directly released into extrasynaptic space. This longer-range communication has been called "volume" transmission (1, S1; S references can be found in Supporting Information). All brain functions, from controlling movement to emotions, involve these two forms of chemical communication.Analytical chemistry has an important role to play in developing our understanding of the brain by providing tools for identification and measurement of the many chemicals involved in neurotransmission.     

Maternal folate supply and sex influence gene‐specific DNA methylation in the fetal gut

Scope : Epidemiological evidence supports the developmental origins of health and disease hypothesis that developmental under/over‐nutrition increases adulthood disease risk. Epigenetic markings are one potential mechanism mediating these effects. Altered folate supply may influence methyl group availability for DNA methylation. We reported low folate supply in utero was associated with reduced global DNA methylation in the murine small intestine of adult offspring. We hypothesised that aberrant methylation would be observed during early development. Methods and results : Female C57BL/6J mice were fed diets containing 2 mg folic acid/kg or 0.4 mg folic acid/kg 4 wk before mating and during pregnancy. At 17.5 day gestation, gene methylation in fetal gut was analysed by Pyrosequencing^®. Low folate reduced overall methylation of Slc394a by 3.4% (p=0.038) but did not affect Esr1 or Igf2 differentially methylated region (DMR) 1. There were sex‐specific differences in Slc394a and Esr1 methylation (2.4% higher in females (p=0.002); 4% higher in males (p=0.0014), respectively). Conclusion : This is the first study reporting causal effects of maternal folate depletion on gene‐specific methylation in fetal gut. These observations support reports that altered methyl donor intake during development affects DNA methylation in the offspring. The consequences of epigenetic changes for health throughout the life course remain to be investigated.     

Radon and moisture impacts from interventions integrated with housing energy retrofits

Energy retrofits can reduce air exchange, raising the concern of whether indoor radon and moisture levels could increase. This pre/post-intervention study explored whether simple radon interventions implemented in conjunction with energy retrofits can prevent increases in radon and moisture levels. Treatment homes (n = 98) were matched with control (no energy retrofits or radon intervention) homes (n = 12). Control homes were matched by geographic location and foundation type. t-tests were used to determine whether post-energy retrofit radon and moisture level changes in treatment homes significantly differed from those in control homes. The radon interventions succeeded in preventing statistically significant increases in first floor radon using arithmetic (p = 0.749) and geometric means (p = 0.120). In basements, arithmetic (p = 0.060) and geometric (p = 0.092) mean radon levels statistically significantly increased, consistent with previous studies which found that basement radon levels may increase even if first floor levels remain unchanged. Changes in infiltration were related to changes in radon (p = 0.057 in basements; p = 0.066 on first floors). Only 58% of the change in infiltration was due to air sealing, with the rest due to weather changes. There was no statistically significant association between air sealing itself and radon levels on the first floor (p = 0.664). Moisture levels also did not significantly increase.