Parallel propagating electromagnetic waves in magnetized quantum electron plasmas with finite temperature.

We studied parallel propagating electromagnetic waves in a magnetized quantum electron plasma of finite temperature, as an extension of our previous study on a zero temperature plasma. We obtained simple analytic dispersion relations in the long wavelength limit that included the thermal effect as correction terms to the zero temperature results. As in the zero temperature case, the lower branch of the R wave showed significant damping and became ill-defined at short wavelengths. Quantum effects seemed to give qualitative changes, such as the appearance of anomalous dispersion regions, to the classical dispersion relations when v_{F}/v_{th}≤0.2 for a set of exemplary parameters of v_{F}=0.1c and ω_{ce}/ω_{pe}=0.05 was used. We also noted that introduction of the Planck constant in the quantum Vlasov equation changed the shape of the anomalous dispersion region qualitatively, by forming a normal dispersion region in the middle of the original single broad anomalous dispersion region.

SIRT1 is increased in affected brain regions and hypothalamic metabolic pathways are altered in Huntington disease.

AIMS: Metabolic dysfunction is involved in modulating the disease process in Huntington disease (HD) but the underlying mechanisms are not known. The aim of this study was to investigate if the metabolic regulators sirtuins are affected in HD. METHODS: Quantitative real-time polymerase chain reactions were used to assess levels of SIRT1-3 and downstream targets in post mortem brain tissue from HD patients and control cases as well as after selective hypothalamic expression of mutant huntingtin (HTT) using recombinant adeno-associated viral vectors in mice. RESULTS: We show that mRNA levels of the metabolic regulator SIRT1 are increased in the striatum and the cerebral cortex but not in the less affected cerebellum in post mortem HD brains. Levels of SIRT2 are only increased in the striatum and SIRT3 is not affected in HD. Interestingly, mRNA levels of SIRT1 are selectively increased in the lateral hypothalamic area (LHA) and ventromedial hypothalamus (VMH) in HD. Further analyses of the LHA and VMH confirmed pathological changes in these regions including effects on SIRT1 downstream targets and reduced mRNA levels of orexin (hypocretin), prodynorphin and melanin-concentrating hormone (MCH) in the LHA and of brain-derived neurotrophic factor (BDNF) in the VMH. Analyses after selective hypothalamic expression of mutant HTT suggest that effects on BDNF, orexin, dynorphin and MCH are early and direct, whereas changes in SIRT1 require more widespread expression of mutant HTT. CONCLUSIONS: We show that SIRT1 expression is increased in HD-affected brain regions and that metabolic pathways are altered in the HD hypothalamus.

Detailed assessment of hypothalamic damage in craniopharyngioma patients with obesity.

BACKGROUND/OBJECTIVES: Hypothalamic obesity (HO) occurs in 50% of patients with the pituitary tumor craniopharyngioma (CP). Attempts have been made to predict the risk of HO based on hypothalamic (HT) damage on magnetic resonance imaging (MRI), but none have included volumetry. We performed qualitative and quantitative volumetric analyses of HT damage. The results were explored in relation to feeding related peptides and body fat. SUBJECTS/METHODS: A cross-sectional study of childhood onset CPs involving 3 Tesla MRI, was performed at median 22 years after first operation; 41 CPs, median age 35 (range: 17-56), of whom 23 had HT damage, were compared to 32 controls. After exclusions, 35 patients and 31 controls remained in the MRI study. Main outcome measures were the relation of metabolic parameters to HT volume and qualitative analyses of HT damage. RESULTS: Metabolic parameters scored persistently very high in vascular risk particularly among HT damaged patients. Patients had smaller HT volumes compared to controls 769 (35-1168) mm3 vs. 879 (775-1086) mm3; P < 0.001. HT volume correlated negatively with fat mass and leptin among CP patients (rs = -0.67; P < .001; rs = -0.53; P = 0.001), and explained 39% of the variation in fat mass. For every 100 mm3 increase in HT volume fat mass decreased by 2.7 kg (95% CI: 1.5-3.9; P < 0.001). Qualitative assessments revealed HT damage in three out of six patients with normal volumetry, but HT damage according to operation records. CONCLUSIONS: A decrease in HT volume was associated with an increase in fat mass and leptin. We present a method with a high inter-rater reliability (0.94) that can be applied by nonradiologists for the assessment of HT damage. The method may be valuable in the risk assessment of diseases involving the HT.

Vitamin A status of Filipino preschool children given a massive oral dose.

The protection period of a 200,000 IU of vitamin A on Filipino children was determined. Subjects were 105 children aged 1-5 years given a single massive dose during the "Araw ng Sangkap Pinoy" (ASAP) in March 1995. Serum retinol was measured by HPLC at baseline, one, two, four and six months after the administration of the dose. Results showed that baseline serum retinol levels were significantly lower than all follow-up values. Serum retinol values were maintained at levels higher than pre-supplementation values although the values decreased on the second month after supplementation. The proportions of deficient and low (< 20 microg/dl) levels were significantly lower one and six months after supplementation. All follow-up serum retinol levels of children with deficient and low values at baseline were significantly lower (p < 0.001) than those with normal values. The WHO recommendation of 200,000 IU was effective in increasing serum retinol concentrations and maintaining it above pre-supplementation levels up to 6 months after administration of the dose. It also replenished organic vitamin A reserves as shown by the dose response (S30DR) approach. Incidence of infection also decreased among the children. Supplementation with vitamin A has likewise resulted in an increase in hemoglobin values and a decrease in the proportion of anemics (Hb < 11.0 g/dl) among the children.

Iron status of Filipino infants and preschoolers using plasma ferritin and transferrin receptor levels.

Iron status of 1,861 Filipino infants and preschoolers was evaluated by measurements of plasma ferritin (PF), transferrin receptor (TR) and hemoglobin (Hb). One group of subjects (Group I) consisted of all anemic subjects together with a systematic subsample from the Fourth National Nutrition Survey-Biochemical Phase. Results showed that depleted iron stores based on PF (< 12.0 ng/ml) was present in 70.0% of infants and 60.5% of preschoolers. Tissue iron deficiency based on TR (> 8.5 mg/l) was present in higher proportion (80.0% and 73.7% for infants and preschoolers) which was comparable to the proportion of anemia (80.3%). In a subgroup of subjects from the Country Program for Children IV (Group 2) elevated TR was present in 61.4% of infants and 46.5% of preschoolers. A lower proportion of depleted iron stores of 22.7% in infants and 15.2% in preschoolers was observed. Correlation test showed that there was a closer relationship between Hb and TR (r = -0.42) than Hb and PF (r = 0.20) even if PF was expected to give a higher proportion of values below normal. The occurrence of anemia in the presence of elevated TR without any decrease in PF values suggest that the diagnostic ability of PF could be limited in the presence of infection. Therefore, future studies should include biochemical tests such as C-reactive proteins (CRP) to determine the extent of association between anemia and infection.

Suppurative sinusitis in critically ill patients: a case report and review of the literature.

Nosocomial sinusitis is occasionally overlooked as a source of sepsis in critically ill patients. Physical examination is usually unreliable and purulent nasal discharge is absent up to 73% of the time. Computed tomography scans of the sinuses and aspiration and culture of sinus fluid are the hallmark of diagnosis. Therapy consists of removal of tubes and packing, appropriate antibiotics, and drainage. Risk factors for nosocomial sinusitis include nasotracheal tubes, nasogastric tubes, prior steroid and antibiotic therapy, and facial fractures. This article reports a case of suppurative sinusitis following prolonged intubation and reviews the literature.

Menstrual blood loss and iron nutrition in Filipino women.

Menstrual blood loss was measured in 80 apparently healthy women aged 15-44 years. The study showed a median menstrual blood loss of 37.1 ml per period and the range was from 5.4-169.0 ml. With an average menstrual cycle of 29 days and a mean hemoglobin content of 12.8 g/dl the average iron loss was estimated to be about 0.55 mg/day. The simultaneous effects of menstrual iron loss and dietary iron intake on the iron status of menstruating women were examined using multiple regression analysis. The parameters used to measure iron status were serum iron, transferrin saturation index (TSI), hemoglobin and mean corpuscular hemoglobin concentration (MCHC). Among these parameters, TSI was found to be the most sensitive indicator of changes in factors affecting iron balance moreover, it was found that with greater menstrual loss and decreasing iron intake, there was a marked fall in TSI. However, the decline of TSI did not reach a level at which deficiency of iron transport would have occurred. These results suggest that iron intake was enough to replenish the iron lost in menstruation. Results of statistical analysis showed that the upper limit of menstrual blood loss should be about 80 ml per period. Any loss above this level for continuously long period of time may lead to anemia. This condition is further aggravated by insufficient iron intake. The data from this study are useful in estimating the recommended dietary allowance (RDA) for iron for menstruating Filipino women. They will also serve as a basis of management of patients in medical practice in terms of evaluating risk of and treatment of iron-deficiency anemia.

Effect of anaemia and other maternal characteristics on birthweight.

A cross-sectional study was done on 982 mothers who delivered in four different government hospitals in Metro Manila and whose pregnancy was unassociated with pre-eclampsia, diabetes mellitus, chronic hypertension, cardiovascular disease, abruptio placenta, placenta praevia and multiple pregnancy. The relationship of birthweight and anaemia and other maternal characteristics was examined by multiple regression analysis. Birthweights did not correlate with maternal haemoglobin levels. However, anaemic mothers showed placental hypertrophy. The hypertrophy is probably a compensatory physiological response to ensure adequate oxygen supply to the fetus. Birthweight increased with gestational age affirming the fact that low birthweight is partly due to shortened gestational age. Haemoglobin level significantly increased with maternal age but decreased with increasing parity.