Cardiac natriuretic peptides act via p38 MAPK to induce the brown fat thermogenic program in mouse and human adipocytes

The ability of mammals to resist body fat accumulation is linked to their ability to expand the number and activity of "brown adipocytes" within white fat depots. Activation of β-adrenergic receptors (β-ARs) can induce a functional "brown-like" adipocyte phenotype. As cardiac natriuretic peptides (NPs) and β-AR agonists are similarly potent at stimulating lipolysis in human adipocytes, we investigated whether NPs could induce human and mouse adipocytes to acquire brown adipocyte features, including a capacity for thermogenic energy expenditure mediated by uncoupling protein 1 (UCP1). In human adipocytes, atrial NP (ANP) and ventricular NP (BNP) activated PPARγ coactivator-1α (PGC-1α) and UCP1 expression, induced mitochondriogenesis, and increased uncoupled and total respiration. At low concentrations, ANP and β-AR agonists additively enhanced expression of brown fat and mitochondrial markers in a p38 MAPK-dependent manner. Mice exposed to cold temperatures had increased levels of circulating NPs as well as higher expression of NP signaling receptor and lower expression of the NP clearance receptor (Nprc) in brown adipose tissue (BAT) and white adipose tissue (WAT). NPR-C(-/-) mice had markedly smaller WAT and BAT depots but higher expression of thermogenic genes such as Ucp1. Infusion of BNP into mice robustly increased Ucp1 and Pgc-1α expression in WAT and BAT, with corresponding elevation of respiration and energy expenditure. These results suggest that NPs promote "browning" of white adipocytes to increase energy expenditure, defining the heart as a central regulator of adipose tissue biology.     

Asymptomatic carriage of Leishmania in family members of patients with visceral leishmaniasis in Central Tunisia

Introduction

In Tunisia, asymptomatic carriage of Leishmania is poorly documented.

Objective

The aim of the present study was to estimate the frequency of asymptomatic infection among the family members of patients with patent visceral leishmaniasis by using the Western blotting kit based on 14 and 16 kDa bands.

Material and methods

We tested 94 sera collected from 24 patients with patent visceral leishmaniasis and 70 from their families’ members.

Results

The rate of seropositivity was 100% in the group of patients and 54.3% in the group of families’ members. The analysis of the Western blotting patterns showed that the 33 kDa, 24 kDa and to a lesser extent the 22 kDa band were very indicative of patent visceral leishmaniasis in contrast to asymptomatic infection where these bands were very rarely detected.

Conclusion

The results reported herein showed the high frequency of asymptomatic carriers of Leishmania among the families’ members of visceral leishmaniasis cases and the usefulness of the Western blotting as a screening technique and in distinguishing between patent visceral leishmaniasis and the asymptomatic carriage of Leishmania.     

Propriétés antifongiques des huiles essentielles de Biota orientalis L.

The chemical composition of essential oils isolated by hydrodistillation from needles and cones of Biota orientalis L. was analyzed by gas chromatography-flame ionization detection (GC-FID) and gas chromatography-mass spectrometry (GC-MS). Twenty one compounds were identified in Biota orientalis essential oil which appeared to be rich in monoterpene hydrocarbons. Quantitative differences mainly, between cone and needle oils, were observed, although they displayed the same chemotype. For both oils, α-pinene (67 and 47% respectively in cones and needles), β-phellandrene (5.1 and 10.9%) and α-cedrol (4.6 and 7.5%) were the major constituents. The study of their antifungal activity towards ten plants pathogenic fungi revealed interesting properties that could be applied as biofungicide.     

The Acute Effects of Aerobic Dance Exercise with and without Face Mask Use on Attention,Perceived Exertion and Mood States

The present study aimed to determine the effect of wearing a face mask during aerobic dance exercise on cognitive function, more specifically on attention, as well as on perceived exertion and mood states. Thirteen healthy college students (9 males and 4 females: mean age = 17.5 years, height = 1.72 m, weight = 71.00 kg) volunteered to participate in this study. They were randomized to perform aerobic dance exercise while wearing a cloth face mask or no mask or a control condition (sitting on a comfortable chair and reading information about the health benefits of aerobic dance exercise) on three separate occasions (with at least one week of interval). Rate of perceived exertion (RPE), the Brunel Mood Scale (BRUMS) and d2 Attention assessment were assessed before and immediately after each condition. The results demonstrated higher concentration performance for the aerobic dance exercise without face mask than the control condition (p = 0.05). Post RPE and BRUMS fatigue subscale values were significantly higher in the aerobic dance exercise with face mask as compared to the aerobic dance exercise without face mask and control condition (all, p < 0.05). BRUMS vigor subscale value significantly differed across conditions (F = 113.84, p < 0.001, ES = 0.86) and was significantly higher in the aerobic dance exercise group without face mask as compared to the aerobic dance exercise with face mask and the control conditions (both, p < 0.001). This study suggests that face mask use during aerobic dance exercise with moderate intensity did not affect attention. Practitioners, students and athletes should avoid wearing face mask while practicing physical activity or aerobic dance exercise with moderate intensity to improve its acute effect on cognitive function.     

Multischool, international survey of medical students' attitudes toward "holism".

PURPOSE: Core and optional courses of study in complementary and alternative medicine (CAM) are being incorporated into medical curricula. The authors carried out this study to validate a tool to examine students' attitudes toward holism and CAM and explore the relationships between their attitudes and other demographic and education-related characteristics in a large, multischool, international sample of medical students. METHOD: In 2003 the authors used a modified version of the Integrated Medicine Attitude Questionnaire (IMAQ) to survey students at a total of six medical schools in the United Kingdom, New Zealand, Canada, the United States, and Hong Kong, China. A three-factor model was tested using confirmatory factor analysis, and the internal consistency of the factors were identified using Cronbach's alpha coefficients. A multiple-indicator multiple-cause (MIMIC) analysis was carried out to determine the relationship between IMAQ factors and student characteristics. RESULTS: The authors validated a three-factor model for the IMAQ: (1) attitudes toward holism, (2) attitudes toward the effectiveness of CAM, and (3) attitudes toward introspection and the doctor-patient relationship. Cronbach's alpha coefficients ranged from .41 to .71. The MIMIC model indicated that various background variables were associated with IMAQ factors (gender, race/ethnicity, and school), depending on whether students had previously visited a CAM practitioner and whether students were willing to undertake a special study module in CAM. CONCLUSIONS: Further development work on the IMAQ is required and qualitative research to verify and examine the reasons behind the relationships found in this study between students' attitudes to holism and their demographic and education-related characteristics.     

Axonal branching of medullary swallowing neurons projecting on the trigeminal and hypoglossal motor nuclei: demonstration by electrophysiological and fluorescent double labeling techniques

Summary The projections of ventral medullary reticular neurons on both trigeminal (Vth) and hypoglossal (XIIth) motor nucleus were studied in sheep anesthetized with halothane. In a first series of experiments, extracellular microelectrodes were used to record the activity of medullary swallowing interneurons (SINs) located in the ventral region (around the nucleus ambiguus) of the swallowing center. Antidromic activation after electrical stimulation of the Vth and XIIth nuclei was tested in 83 SINs. For 38 SINs a clear antidromic activation was observed and for 8 of them the response was triggered by stimulation of either nucleus. As confirmed by the reciprocal collision test, these 8 SINs had branched axons sending information to both nuclei tested. Average latencies for antidromic activation of branched SINs after stimulation of the XIIth and the Vth motor nucleus were 2.2±0.6 ms and 2.7±0.8 ms respectively. The axonal conduction velocity of these neurons was 4.4±1.3 m/s for the collateral to the Vth motor nucleus and 2.7±0.7 m/s for axons projecting to the XIIth motor nucleus. In a second series of experiments the double retrograde labeling technique was used to confirm the existence of neurons with branched axons in the medullary regions corresponding to the swallowing center. Small and well localized injections of Fast Blue (FB) and Diamidino Yellow (DY) fluorescent tracers were made in the Vth and in the XIIth motor nucleus respectively. A relatively large number of double-labeled cells was found in the ventral region of swallowing center (reticular formation around the nucleus ambiguus, 2–4 mm in front of obex). Such neurons (supplying both the XIIth and the Vth motor nucleus) appeared mixed with those innervating only either the XIIth or the Vth motor nucleus. Each type of neuron, i.e. single or double labeled, was shown to have bilateral distribution with an ipsilateral predominance.     

Toxicological studies on Globularia alypum and Zygophyllum gaetulum in rats

This work examines the toxicological effects of Globularia alypum leaves and Zygophyllum gaetulum aerial parts used in the traditional treatment of diabetes mellitus in Morocco. The LD₅₀ after oral administration of the plant infusions was higher than 10 g/kg body weight. Chronic toxicity was evaluated by analysis of biochemical and haematological parameters and by anatomo-histopathological studies. It is suggested that these plants have no toxicological effects in rats. Copyright © 1998 John Wiley & Sons, Ltd.     

Transgenerational modification of hippocampus TNF-α and S100B levels in the offspring of rats chronically exposed to morphine during adolescence

Background: TNF-α and S100B are important signaling factors that are involved in many aberrant conditions of the brain. Chronic morphine exposure causes aberrant modifications in the brain. Objectives: We examined the consequences of chronic morphine consumption by parents before mating on hippocampus TNF-α and S100B levels in the parents and their offspring. Methods: A total of 12 adult female and 12 adult male Wistar rats were used as parents. Each gender was divided randomly into two groups: control and morphine consumer. Morphine consumer groups received morphine sulfate dissolved in drinking water (0.4 mg/ml) for 60 days. Control groups received water. Thirty days before mating, morphine was replaced with water. All offspring also received water. The hippocampus of both parental and offspring groups was extracted to measure TNF-α and S100B levels using an ELISA. Results: Hippocampus TNF-α levels were significantly increased due to chronic morphine use in both male and female parents compared to those of control parents (P < 0.01). Moreover, both male and female offspring of morphine-exposed parents showed a significant increase in hippocampus TNF-α levels compared to those of control offspring (P < 0.01). Hippocampus levels of S100B were significantly decreased in male (P < 0.05) but not female morphine consumer parents relative to control parents. Both male and female offspring of morphine-exposed parents showed significant decreases in hippocampus S100B levels (P < 0.05) compared to those of control offspring. Conclusions: The consequences of chronic morphine use by parents, even when it is stopped long before mating and pregnancy, could induce modifications in the hippocampus of the next generation.