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Electromagnetic Radiation Health Effects in Exposed and Non-Exposed Residents in Penang  [PDF]
Adlina Suleiman, Thor Teong Gee, Ambigga Devi Krishnapillai, Khalifah Mohamad Khalil, Mohammad Wisman Abdul Hamid, Marami Mustapa
Journal of Geoscience and Environment Protection (GEP) , 2014, DOI: 10.4236/gep.2014.22012
Abstract: A comparative study was conducted between residents exposed and not exposed to electromagnetic radiation (EMR) from TELCO towers in Penang Island with the objective of determining the possible health effects using 14 non-specific health symptoms (NSHS). Interviews on 201 respondents were conducted using structured questionnaire for demographic details, health related problems and the public concern. Comparison of symptoms frequencies and its significance (Chi-square test) between the exposed and not exposed residents from the TELCO tower showed statistical significance (p < 0.05) for headache, giddiness, insomnia, loss of memory, diarrhea, mental slowness, reduced reaction time and mood swing. The odds ratio for the development of the NSHS scored > 1 for all that gave a conclusion that respondents who were exposed were more likely to suffer symptoms as compared to the respondents who were not exposed to EMR. This outcome showed that the existence of TELCO tower in these communities has detrimental health effects towards the residents who were exposed to the electromagnetic fields radiation that was emitted. Measures to be taken to minimize adverse health effects on residents should include imposing more stringent guidelines in terms of safety distance and radiation intensity, practicing of WHO precautionary approach, encouraging electromagnetic fields radiation related conference, researches and public awareness, sharing of transceivers by TELCO companies and using protective barriers. These steps will ultimately promote a healthier, harmonious and sustainable living environment.
Aromatase immunoreactivity in fetal ovine neuronal cell cultures exposed to oxidative injury  [cached]
G. Lepore,S. Gadau,A. Mura,M. Zedda
European Journal of Histochemistry , 2009, DOI: 10.4081/ejh.2009.e28
Abstract: A lot of evidence testifies that aromatase is expressed in the central nervous system where it has been detected not only in hypothalamic and limbic regions but also in the cerebral cortex and spinal cord. In physiological conditions, aromatase is expressed exclusively by neurons, where it has been mainly found in cell bodies, processes and synaptic terminals. Moreover, primary cultured cortical astrocytes from female rats are more resistant to oxidant cell death than those from males, suggesting a protective role of estradiol. The aim of this study was to evaluate changes in aromatase expression in response to 3-nitro-L-tyrosine, a marker of oxidative stress, in primary neuronal cell cultures from brains of 60-day old sheep fetuses. Cells were identified as neurons by using class III b- tubulin, a marker of neuronal cells. Two morphological types were consistently recognizable: i) bipolar cells with an oval cell body; ii) multipolar cells whose processes formed a wide net with those of adjacent cells. In situ hybridization technique performed on 60-day old fetal neurons revealed that in baseline conditions aromatase gene expression occurs. Importantly, cells exposed to 360 ?M 3-nitro-L-tyrosine were fewer and showed more globular shape and shorter cytoplasmic processes in comparison to control cells. The immunocytochemical study with anti-aromatase antibody revealed that cells exposed to 360 ?M 3-nitro-L-tyrosine were significantly more immunoreactive than control cells. Thus, it can be postulated that the oxidant effects of the amino acid analogue 3- nitro-L-tyrosine could be counterbalanced by an increase in aromatase expression that in turn can lead to the formation of neuroprotective estradiol via aromatization of testosterone.
Normal Thymic Size and Low Rate of Infections in Human Donor Milk Fed HIV-Exposed Uninfected Infants from Birth to 18 Months of Age  [PDF]
Dorthe Lisbeth Jeppesen,Annette Kj?r Ersb?ll,Tine Ursula Hoppe,Susanne Dam Nielsen,Niels Henrik Valerius
International Journal of Pediatrics , 2013, DOI: 10.1155/2013/373790
Abstract: Objective. To evaluate the immune function in HIV-exposed uninfected (HIV-EU) infants fed human donor milk. Methods. Ultrasound-obtained thymic index (Ti), T-lymphocyte subsets, and the number of infections were examined from birth to 18 months of age in 18 HIV-EU infants. The infants were compared to a cohort of 47 term, HIV-unexposed breastfed or formula-fed infants. Results. The thymic size at 12 months of age was not significantly different between the HIV-EU group and the control infants ( ). At 4 months of age, the HIV-EU infants had significantly fewer infections than the control infants ( ). Furthermore, in the control group, the infants exclusively breastfed at 4 months of age had significantly fewer infections at 8 months when compared to age-matched formula-fed infants ( ). Conclusion. HIV-EU infants fed human donor milk have normal growth of thymus and contract fewer infections than other healthy infants. This finding along with fewer infections in exclusively breastfed infants compared to formula-fed infants supports the beneficial effect of human milk on the immune system. We suggest, when breastfeeding is not possible, that providing human donor milk to vulnerable groups of infants will be beneficial for their maturing immune system. 1. Introduction Vertical transmission of HIV from HIV-positive mothers to their infants is, in industrialised countries, reduced to less than 1-2% [1–3]. Consequently, the number of HIV-exposed uninfected (HIV-EU) infants in the world is growing. Despite HIV-EU infants remaining uninfected, there have been reports of impaired immune function and reduced CD4 counts in HIV-EU newborns [4–8]. However, reports on the long-term impact of HIV exposure on the immune system have been conflicting and there have been very few studies of whether the infection burden in HIV-EU infants is higher than in HIV-unexposed infants [9, 10]. The thymus plays a key role in the development of a functional immune system, providing the environment for T-lymphocyte maturation and being a central organ for the development and maintenance of cell-mediated immunity. The thymus is also known to be a target organ in HIV-infection [11]. The transition of T-cell progenitors in the thymus has been extensively evaluated, but the significance of the size or alterations in the size of the thymus in infancy is still unclear [12–15]. The positive correlation between thymic size and weight and length at birth and during the first months of life is well known and infections are reported to result in decreasing thymic size [16–20]. We have also
Immature CD4+CD8+ Thymocytes Are Preferentially Infected by Measles Virus in Human Thymic Organ Cultures  [PDF]
Yukari Okamoto, Luca A. Vricella, William J. Moss, Diane E. Griffin
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0045999
Abstract: Cells of the human immune system are important target cells for measles virus (MeV) infection and infection of these cells may contribute to the immunologic abnormalities and immune suppression that characterize measles. The thymus is the site for production of na?ve T lymphocytes and is infected during measles. To determine which populations of thymocytes are susceptible to MeV infection and whether strains of MeV differ in their ability to infect thymocytes, we used ex vivo human thymus organ cultures to assess the relative susceptibility of different subpopulations of thymocytes to infection with wild type and vaccine strains of MeV. Thymocytes were susceptible to MeV infection with the most replication in immature CD4+CD8+ double positive cells. Susceptibility correlated with the level of expression of the MeV receptor CD150. Wild type strains of MeV infected thymocytes more efficiently than the Edmonston vaccine strain. Thymus cultures from children ≥3 years of age were less susceptible to MeV infection than cultures from children 5 to 15 months of age. Resistance in one 7 year-old child was associated with production of interferon-gamma suggesting that vaccination may result in MeV-specific memory T cells in the thymus. We conclude that immature thymocytes are susceptible to MeV infection and thymocyte infection may contribute to the immunologic abnormalities associated with measles.
Ultrastructural Change of Cerebellum in Exposed Rats to 3mT Electromagnetic Field
Allahvaysi Ozra,Solaeymani-Rad Jafar,Lida Moradi,Ghasem Saki
Journal of Biological Sciences , 2010,
Abstract: The aim of this study was to investigate ultrastructural changes of Cerebellum in 3mT electromagnetic field exposed rats. Total 30 adult female Wister rats with 3 months of age and weighing 210±10.6 g were used in this study. All female rats subdivided randomly to 2 groups: group 1, serve as untreated controls; group 2, was exposed to 3mT EMF for 4 months, 4 h day-1. After 120 days all rats were killed and their tissue samples from Cerebellum were removed and prepared for electron microscopic studies. Present finding clearly demonstrated that number of purkinje cells in the cerebellum of EMF- exposed rats were decreased significantly (p<0.01) in comparison to control group. The other changes include: condensation of nuclei, dilatation of endoplasmic reticulum, breakdown and disappearance of crista in mitochondria and vacuolization of cytoplasm in the purkinje cells of cerebellum. The mean nuclear diameter in purkinje cells were 45.35±22.85 mm and 26.79±16.36 mm in control and experimental group respectively. The statistical analysis showed that the difference between two group was significant (p = 0.03). Axial ratio of nucleus of purkinje in control and experimental groups were 1.86±0.41 and 1.55±0.14 mm, respectively. The axial ratio of nucleus in purkinje of EMF-exposed cerebellum were decreased significantly in comparison to control group (p = 0.02). These findings indicate that long-term exposure to EMF has detrimental effects on central nervous system at cellular level.
Neurovegetative Disturbances in Workers Exposed to 50 Hz Electromagnetic Fields
Alicja Bortkiewicz , El bieta Gadzicka , Marek Zmy lony , Wies aw Szymczak
International Journal of Occupational Medicine and Environmental Health , 2006, DOI: 10.2478/v10001-006-0001-1
Abstract: Objectives: Since the circulatory and nervous systems are composed of electrically excitable tissues, it is plausible that they can be stimulated by electromagnetic fields (EMF). No clinical studies have as yet been carried out to explain whether and how occupational exposure to 50 Hz EMF can influence the neurovegetative regulation of the cardiovascular function. The present project was undertaken to assess the autonomic function in workers occupationally exposed to 50 Hz EMF, by analyzing the heart rate variability. Materials and Methods: The study group comprised 63 workers of switchyard substations, aged 22-67 years (39.2 ± 10.0 years), and the control group 42 workers of radio link stations, aged 20-68 years (40.7 ± 9.2 years), employed at workposts free from EMF exposure. The age range and employment duration in both groups did not differ significantly. To assess the neurovegetative regulation of the cardiac function, heart rate variability (HRV) analysis was made based on 512 normal heart beats recorded at rest. The analysis, performed using fast Fourier transformation, concerned the time-and frequency-domain HRV parameters. Power spectrum in the very low (VLF), low (LF) and high (HF) frequency bands was determined. Results: The relative risk of decreased HRV (STD R-R < 27 ms), calculated with use of a logistic regression model, was significantly higher in the exposed group than in controls (OR = 2.8). The VLF power spectrum was significantly higher in the exposed group and correlated with the exposure level. The percentage of subjects with dominant sympathetic function (LF/HF>1) was significantly higher in the study group than in controls (65% vs. 47%). Conclusions: It was concluded that occupational exposure to 50 Hz EMF could influence the neurovegetative regulation of the cardiovascular system.
Electromagnetic Biostimulation of Living Cultures for Biotechnology, Biofuel and Bioenergy Applications  [PDF]
Ryan W. Hunt,Andrey Zavalin,Ashish Bhatnagar,Senthil Chinnasamy,Keshav C. Das
International Journal of Molecular Sciences , 2009, DOI: 10.3390/ijms10104515
Abstract: The surge of interest in bioenergy has been marked with increasing efforts in research and development to identify new sources of biomass and to incorporate cutting-edge biotechnology to improve efficiency and increase yields. It is evident that various microorganisms will play an integral role in the development of this newly emerging industry, such as yeast for ethanol and Escherichia coli for fine chemical fermentation. However, it appears that microalgae have become the most promising prospect for biomass production due to their ability to grow fast, produce large quantities of lipids, carbohydrates and proteins, thrive in poor quality waters, sequester and recycle carbon dioxide from industrial flue gases and remove pollutants from industrial, agricultural and municipal wastewaters. In an attempt to better understand and manipulate microorganisms for optimum production capacity, many researchers have investigated alternative methods for stimulating their growth and metabolic behavior. One such novel approach is the use of electromagnetic fields for the stimulation of growth and metabolic cascades and controlling biochemical pathways. An effort has been made in this review to consolidate the information on the current status of biostimulation research to enhance microbial growth and metabolism using electromagnetic fields. It summarizes information on the biostimulatory effects on growth and other biological processes to obtain insight regarding factors and dosages that lead to the stimulation and also what kind of processes have been reportedly affected. Diverse mechanistic theories and explanations for biological effects of electromagnetic fields on intra and extracellular environment have been discussed. The foundations of biophysical interactions such as bioelectromagnetic and biophotonic communication and organization within living systems are expounded with special consideration for spatiotemporal aspects of electromagnetic topology, leading to the potential of multipolar electromagnetic systems. The future direction for the use of biostimulation using bioelectromagnetic, biophotonic and electrochemical methods have been proposed for biotechnology industries in general with emphasis on an holistic biofuel system encompassing production of algal biomass, its processing and conversion to biofuel.
Asteroid thermophysical modeling  [PDF]
Marco Delbo,Michael Mueller,Joshua P. Emery,Ben Rozitis,Maria Teresa Capria
Physics , 2015,
Abstract: The field of asteroid thermophysical modeling has experienced an extraordinary growth in the last ten years, as new thermal infrared data became available for hundreds of thousands of asteroids. The infrared emission of asteroids depends on the body's size, shape, albedo, thermal inertia, roughness and rotational properties. These parameters can therefore be derived by thermophysical modeling of infrared data. Thermophysical modeling led to asteroid size estimates that were confirmed at the few-percent level by later spacecraft visits. We discuss how instrumentation advances now allow mid-infrared interferometric observations as well as high-accuracy spectro-photometry, posing their own set of thermal-modeling challenges.We present major breakthroughs achieved in studies of the thermal inertia, a sensitive indicator for the nature of asteroids soils, allowing us, for instance, to determine the grain size of asteroidal regoliths. Thermal inertia also governs non-gravitational effects on asteroid orbits, requiring thermophysical modeling for precise asteroid dynamical studies. The radiative heating of asteroids, meteoroids, and comets from the Sun also governs the thermal stress in surface material; only recently has it been recognized as a significant weathering process. Asteroid space missions with thermal infrared instruments are currently undergoing study at all major space agencies. This will require a high level of sophistication of thermophysical models in order to analyze high-quality spacecraft data.
Ultrastructural Alterations and Occurrence of Apoptosis in Developing Follicles Exposed to Low Frequency Electromagnetic Field in Rat Ovary  [PDF]
Leila Roushangar,Jafar Soleimani Rad
Pakistan Journal of Biological Sciences , 2007,
Abstract: Humans are continuously exposed to harmful environmental factors, including Electromagnetic Fields (EMF) produced by home appliances, diagnostic tools and industrial instruments. The present study investigates morphologically the effects of EMF on ovarian follicles. Female Wistar rats were exposed to 3 mili Tesla EMF for 4 h day-1 for 4 months, the ovaries from both experimental and control groups were processed for Transmission Electron Microscopy (TEM) and TUNEL reaction technique. TEM revealed that in the oocytes from experimental group the nuclei were shrunken and zona pellucida appeared narrower than those in the control group. The number of microvilli were decreased significantly and in their cytoplasm there were several lipid droplets and organels were dispersed. Signs of apoptosis such as condensed nuclei, chromatin margination and nuclear membrane dilatation were common in granulosa and corona radiata cells from the EMF-exposed rats than those from the control group. Primary morphological changes in the granulosa cells from this group were retraction of granulosa cells, loss of microvilli and condensation or loss of mitochondrial cristae. The morphological changes in oocytes seem to indicate the cytotoxic effect of EMF and the changes occurred in granulosa cells coincide with initiation of apoptosis in granulosa cells. Present results suggest that EMF exposure may interfere with normal process of folliculogenesis.
Multiloculated cervical thymic cyst  [cached]
Niranjan J,Santosh K,Prabhakar G
Journal of Indian Association of Pediatric Surgeons , 2011,
Abstract: In this study, we report a rare case of cervical thymic cyst in an 8-year-old child.
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