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Exponential interindividual handling in wireless communication system has raised possible doubts in the biological aspects of radiofrequency (RF) exposure on human brain owing to its close proximity to the mobile phone. In the nervous system, calcium (Ca(2+)) plays a critical role in releasing neurotransmitters, generating action potential and membrane integrity. Alterations in intracellular Ca(2+) concentration trigger aberrant synaptic action or cause neuronal apoptosis, which may exert an influence on the cellular pathology for learning and memory in the hippocampus. Calcium binding proteins like calbindin D28-K (CB) is responsible for the maintaining and controlling Ca(2+) homeostasis. Therefore, in the present study, we investigated the effect of RF exposure on rat hippocampus at 835 MHz with low energy (specific absorption rate: SAR=1.6 W/kg) for 3 months by using both CB and glial fibrillary acidic protein (GFAP) specific antibodies by immunohistochemical method. Decrease in CB immunoreactivity (IR) was noted in exposed (E1.6) group with loss of interneurons and pyramidal cells in CA1 area and loss of granule cells. Also, an overall increase in GFAP IR was observed in the hippocampus of E1.6. By TUNEL assay, apoptotic cells were detected in the CA1, CA3 areas and dentate gyrus of hippocampus, which reflects that chronic RF exposure may affect the cell viability. In addition, the increase of GFAP IR due to RF exposure could be well suited with the feature of reactive astrocytosis, which is an abnormal increase in the number of astrocytes due to the loss of nearby neurons. Chronic RF exposure to the rat brain suggested that the decrease of CB IR accompanying apoptosis and increase of GFAP IR might be morphological parameters in the hippocampus damages., (Copyright 2010 Elsevier B.V. All rights reserved.)

Worldwide expansion of mobile phones and electromagnetic field (EMF) exposure has raised question of their possible biological effects on the brain and nervous system. Radiofrequency (RF) radiation might alter intracellular signaling pathways through changes in calcium (Ca(2+)) permeability across cell membranes. Changes in the expression of calcium binding proteins (CaBP) like calbindin D28-k (CB) and calretinin (CR) could indicate impaired Ca(2+)homeostasis due to EMF exposure. CB and CR expression were measured with immunohistochemistry in the hippocampus of mice after EMF exposure at 835 MHz for different exposure times and absorption rates, 1 h/day for 5 days at a specific absorption rate (SAR)=1.6 W/kg, 1 h/day for 5 days at SAR=4.0 W/kg, 5 h/day for 1 day at SAR=1.6 W/kg, 5 h/day for 1 day at SAR=4.0 W/kg, daily exposure for 1 month at SAR=1.6 W/kg. Body weights did not change significantly. CB immunoreactivity (IR) displayed moderate staining of cells in the cornu ammonis (CA) areas and prominently stained granule cells. CR IR revealed prominently stained pyramidal cells with dendrites running perpendicularly in the CA area. Exposure for 1 month produced almost complete loss of pyramidal cells in the CA1 area. CaBP differences could cause changes in cellular Ca(2+)levels, which could have deleterious effect on normal hippocampal functions concerned with neuronal connectivity and integration., (Copyright 2009 Elsevier B.V. All rights reserved.)

The duration and amount of water captured on leaves and its functional significance is highly varied. Leaf surface wettability influences water absorption, gas exchange, pathogen infection, nutrient leaching, contamination by pollutants, self-cleaning properties and in freezing environments the probability of extrinsic ice nucleation. To test the impact of environment on the development of leaf wettability, this functional trait was measured in 227 dominant plant species along an extreme altitudinal environment gradient (186-5,268 m) on the wet and dry slopes of the Nepalese Himalayas. Plants from the understorey and open places in woodlands were also compared. Leaf wettability was assessed by droplet contact angle (theta), retention and leaf inclination measurement. With increasing altitude leaf wettability decreased significantly parallel to the observed atmospheric temperature decrease (0.5 K/100 m). Leaves from non-freezing tropical and subtropical origins were highly wettable (theta < 90 degrees). Temperate leaves were non-wettable (110 degrees < theta < 130 degrees). Subalpine and alpine leaves were highly non-wettable (130 degrees < theta < 150 degrees) and adaxial pubescence occurred more frequently. Leaves taken from the understorey were more wettable but had a better droplet run off than leaves sampled in open places. In the semi-arid northern slopes (temperate to alpine) of the Himalayas leaf wettability was decreased in comparison to the southern humid side. The majority of the leaves had a low droplet retention <20 degrees ; higher values were linked to high non-wettability (theta > 130 degrees) which was more often observed at high altitude. Good droplet run off at +/-10 degrees inclination was found in highly wettable leaves (theta < 90 degrees) of tropical and subtropical origin and on leaves from the forest understorey. Structural properties for low wettability are developed in cold and dry environments and open sites with frequent dew formation as it appears to be an important functional trait to prevent a number of the negative effects adhering surface water may have.

Background: Although systemic sclerosis is a rare disease, incidence rates have increased recently in the United States. This study investigated the association between systemic sclerosis and exposure to solvents., Methods: A Medline search of articles published between 1966 and 2000 dealing with solvent exposure and systemic sclerosis identified eight studies that met inclusion criteria of the meta-analysis. The studies included seven case-control studies and one cohort study published between 1989 and 1998. A series of meta-analyses of studies on systemic sclerosis and solvent exposure were performed for all studies and for case-control studies. A random effect model was used to calculate a combined estimator of relative risk., Results: The combined estimator of relative risk for all studies was 2.91, with a 95% confidence interval (CI) of 1.60 to 5.30. The combined estimator of relative risk for the seven case-control studies was 3.14 (95% CI, 1.56-6.33)., Conclusions: A statistically significant increased relative risk for all studies and for case-control studies suggests that exposure to organic solvent may be a risk factor for developing systemic sclerosis. Further studies using other study designs and better control of confounders are needed., (Copyright 2001 Wiley-Liss, Inc.)

Objective: To determine the incidence of high-altitude cerebral edema (HACE), acute mountain sickness (AMS), and high-altitude pulmonary edema (HAPE) in pilgrims. Although it is well known that western trekkers suffer from acute mountain sickness (AMS) in the Himalayas, not much is documented about the incidence of AMS in the local population of Nepal that go to high altitude., Methods: The design was a randomized study set at a sacred high-altitude lake at 4300 m at Gosainkund in the Nepal Himalayas. There was a control study at 1300 m at Pashupatinath in Kathmandu, Nepal. The subjects were pilgrims of different ethnic Nepali backgrounds. The Lake Louise consensus for AMS, HACE, and HAPE was used, and oxygen saturation with a pulse oximeter was performed on HACE subjects., Results: Out of 5000 pilgrims, 228 were randomly chosen. Sixty-eight percent had AMS, 31% had HACE, and 5% had HAPE. The mean oxygen saturation of HACE subjects at that altitude was 77%, 87% being normal for 4300 m altitude. Seventy-three percent of the study population were men, yet women had a significantly higher rate of AMS (odds ratio, 4.34; 95% confidence interval, 1.83-10.68), HACE (odds ratio 3.15, confidence interval 1.62-6.12), and HAPE (odds ratio, 5.2; 95% confidence interval, 1.24-24.73)., Conclusions: Such a high incidence of HACE in an epidemiological study using the Lake Louise criteria has, to our knowledge, not been reported before. High-altitude pilgrims, especially women pilgrims in this study, seem to be a very susceptible group. Preventive measures in these pilgrims need to be adopted to avoid AMS, specifically life-threatening HACE and HAPE.