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31.
There are possible hazardous health effects of exposure to radiofrequency electromagnetic radiations emitted from mobile phone on the human reproductive pattern. It is more effective while keeping mobile phones in pocket or near testicular organs. Present review examines the possible concern on radio frequency radiation interaction and biological effects such as enzyme induction, and toxicological effects, including genotoxicity and carcinogenicity, testicular cancer, and reproductive outcomes. Testicular infertility or testicular cancer due to mobile phone or microwave radiations suggests an increased level of reactive oxygen species (ROS). Though generation of ROS in testis has been responsible for possible toxic effects on physiology of reproduction, the reviews of last few decades have well established that these radiations are very harmful and cause mutagenic changes in reproductive pattern and leads to infertility. The debate will be focused on bio-interaction mechanism between mobile phone and testicular cancer due to ROS formation. This causes the biological damage and leads to several changes like decreased sperm count, enzymatic and hormonal changes, DNA damage, and apoptosis formation. In the present review, physics of mobile phone including future research on various aspects has been discussed.  相似文献   
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Y chromosome micro-deletions in idiopathic infertility from Northern India   总被引:3,自引:0,他引:3  
Azoospermia factor locus (AZF) is assumed to contain the genes responsible for spermatogenesis. Deletions in these genes are thought to be pathologically involved in some cases of male infertility associated with azoospermia or oligozoospermia. An attempt was made to establish the prevalence of micro-deletions on the Y chromosome in 79 infertile North Indians with azoospermia and oligozoospermia. Detail clinical examinations as well as endocrinological parameters were also done. Polymerase chain reaction (PCR) micro-deletion analysis was done in 79 infertile men. For this, genomic DNA was extracted from the peripheral blood. Seven sets of primers were used encompassing AZFa, AZFb and AZFc regions. Micro-deletions in five of the 79 cases (6.3%) showed deletions of at least one of the STS markers. Deletions were detected with known and unknown aetiology and at least in one of the infertile male with varicocele. AZF micro-deletions seen in idiopathic infertile males suggest the need for molecular screening in non-idiopathic cases.  相似文献   
34.
Diclofenac sodium (DS) is used primarily to treat fever and to alleviate pain and inflammation. We investigated the effects of DS exposure during gestation on the testes of rat pups to investigate the safety of its use during the prenatal period. Pregnant rats were separated into control, saline, low dose, medium dose and high dose groups. DS was given between weeks 15 and 21 of gestation. Total numbers of spermatogonia and Sertoli cells were counted in the testes of 7-day-old male rats using the physical disector method. By the end of the study, the total number of Sertoli cells was decreased significantly in a dose dependent manner in the medium and high dose groups compared to controls. No significant differences were found in the total number of spermatogonia in the control, saline and low dose DS groups. Medium and high dose DS administration reduced the total number of spermatogonia compared to other groups. We suggest that prenatal administration of DS can cause deleterious effects on the testis development, especially in high doses.  相似文献   
35.
BackgroundVisceral leishmaniasis (VL), with the squeal of Post-kala-azar dermal leishmaniasis (PKDL), is a global threat for health. Studies have shown sodium stibogluconate (SSG) resistance in VL patients with chronic arsenic exposure. Here, we assessed the association between arsenic exposure and risk of developing PKDL in treated VL patients.MethodsIn this retrospective study, PKDL patients (n = 139), earlier treated with SSG or any other drug during VL, were selected from the study cohort. Trained physicians, unaware of arsenic exposure, interviewed them and collected relevant data in a questionnaire format. All probable water sources were identified around the patient’s house and water was collected for evaluation of arsenic concentration. A GIS-based village-level digital database of PKDL cases and arsenic concentration in groundwater was developed and individual point location of PKDL cases were overlaid on an integrated GIS map. We used multivariate logistic regression analysis to assess odds ratios (ORs) for association between arsenic exposure and PKDL development.ResultsOut of the 429 water samples tested, 403 had arsenic content of over 10 μg/L, with highest level of 432 μg/L among the seven study villages. Multivariate adjusted ORs for risk of PKDL development in comparison of arsenic concentrations of 10.1–200 μg/L and 200.1–432.0 μg/L were 1.85 (1.13–3.03) and 2.31 (1.39–3.8) respectively. Interestingly, similar results were found for daily dose of arsenic and total arsenic concentration in urine sample of the individual. The multivariate-adjusted OR for comparison of high baseline arsenic exposure to low baseline arsenic exposure of the individuals in the study cohort was 1.66 (95% CI 1.02–2.7; p = 0.04).ConclusionOur findings indicate the need to consider environmental factors, like long time arsenic exposure, as an additional influence on treated VL patients towards risk of PKDL development in Bihar.  相似文献   
36.
Sweat production is crucial for thermoregulation. However, sweating can be problematic for individuals with spinal cord injuries (SCI), as they display a blunting of sudomotor and vasomotor responses below the level of the injury. Sweat gland density and eccrine gland metabolism in SCI are not well understood. Consequently, this study examined sweat lactate (S-LA) (reflective of sweat gland metabolism), active sweat gland density (SGD), and sweat output per gland (S/G) in 7 SCI athletes and 8 able-bodied (AB) controls matched for arm ergometry VO2peak. A sweat collection device was positioned on the upper scapular and medial calf of each subject just prior to the beginning of the trial, with iodine sweat gland density patches positioned on the upper scapular and medial calf. Participants were tested on a ramp protocol (7 min per stage, 20 W increase per stage) in a common exercise environment (21±1°C, 45-65% relative humidity). An independent t-test revealed lower (p<0.05) SGD (upper scapular) for SCI (22.3 ±14.8 glands · cm−2) vs. AB. (41.0 ± 8.1 glands · cm−2). However, there was no significant difference for S/G between groups. S-LA was significantly greater (p<0.05) during the second exercise stage for SCI (11.5±10.9 mmol · l−1) vs. AB (26.8±11.07 mmol · l−1). These findings suggest that SCI athletes had less active sweat glands compared to the AB group, but the sweat response was similar (SLA, S/G) between AB and SCI athletes. The results suggest similar interglandular metabolic activity irrespective of overall sweat rate.  相似文献   
37.
The coronavirus disease 2019 (COVID-19) has been threatening the globe since the end of November 2019. The disease revealed cracks in the health care system as health care providers across the world were left without guidelines on definitive usage of pharmaceutical agents or vaccines. The World Health Organization (WHO) declared COVID-19 as a pandemic on the 11th of March 2020. Individuals with underlying systemic disorders have reported complications, such as cytokine storms, when infected with the virus. As the number of positive cases and the death toll across the globe continue to rise, various researchers have turned to cell based therapy using stem cells to combat COVID-19. The field of stem cells and regenerative medicine has provided a paradigm shift in treating a disease with minimally invasive techniques that provides maximal clinical and functional outcome for patients. With the available evidence of immunomodulatory and immune-privilege actions, mesenchymal stem cells (MSCs) can repair, regenerate and remodulate the native homeostasis of pulmonary parenchyma with improved pulmonary compliance. This article revolves around the usage of novel MSCs therapy for combating COVID-19.  相似文献   
38.
Cell phone radiation exposure and its biological interaction is the present concern of debate. Present study aimed to investigate the effect of 3G cell phone exposure with computer controlled 2-D stepper motor on 45-day-old male Wistar rat brain. Animals were exposed for 2 h a day for 60 days by using mobile phone with angular movement up to zero to 30°. The variation of the motor is restricted to 90° with respect to the horizontal plane, moving at a pre-determined rate of 2° per minute. Immediately after 60 days of exposure, animals were scarified and numbers of parameters (DNA double-strand break, micronuclei, caspase 3, apoptosis, DNA fragmentation, expression of stress-responsive genes) were performed. Result shows that microwave radiation emitted from 3G mobile phone significantly induced DNA strand breaks in brain. Meanwhile a significant increase in micronuclei, caspase 3 and apoptosis were also observed in exposed group (P < 0.05). Western blotting result shows that 3G mobile phone exposure causes a transient increase in phosphorylation of hsp27, hsp70, and p38 mitogen-activated protein kinase (p38MAPK), which leads to mitochondrial dysfunction-mediated cytochrome c release and subsequent activation of caspases, involved in the process of radiation-induced apoptotic cell death. Study shows that the oxidative stress is the main factor which activates a variety of cellular signal transduction pathways, among them the hsp27/p38MAPK is the pathway of principle stress response. Results conclude that 3G mobile phone radiations affect the brain function and cause several neurological disorders.  相似文献   
39.
An efficient plant regeneration protocol was developed from rhizomes of two Curcuma species C. longa and C. amada. Response was highly dependent on the season, with above 69 % of culture developing adventitious shoots during spring. Greatest regeneration and multiplication was observed in modified Murashige and Skoog (MS) medium supplemented with 13.31 μM benzyladenine and 2.68 μM α-naphthalene acetic acid (NAA) in C. longa or 2.46 μM indolebutyric acid in C. amada. Effect of sugars and agar at different concentrations were also studied and 2 % maltose and 0.7 % agar were found optimum for shoot multiplication and regeneration. Most plantlets developed roots simultaneously but others formed roots when subcultured in ½ MS medium supplemented with 2.68 μM NAA. Plants were successfully hardened in greenhouse with 80 % survival. The genetic purity of micropropagated plantlets was analyzed using RAPD and protein profiles.  相似文献   
40.
The breeding habitat of sandflies is a little studied and poorly understood phenomenon. More importantly, oviposition behaviour is a largely neglected aspect of sandfly biology and this knowledge gap further undermines our understanding of the biology of sandflies. Pheromones released by the eggs play an important role in identifying good sites for oviposition by female insects. Several recent studies have examined the oviposition pheromone. The present study provides a preliminary report on the oviposition behaviour of Phlebotomus argentipes, the only vector of kala-azar (or visceral leishmaniasis) on the Indian sub-continent. Sandflies prefer to oviposit their eggs on surfaces that contain organic substances, especially substances with an odour of decaying animal products and the remains of conspecific eggs. The results presented here suggest that the odour released by the organic substances of old sandfly colony remains that contain dead flies, old unhatched eggs, larval food containing vertebrate faeces, frass and other organic matter serves as an attractant for the ovipositing females of P. argentipes and hence greatly increases the number of oviposited eggs compared to eggs deposited in controlled oviposition pots. This result will be helpful in maintaining an efficient colony of P. argentipes and may be a promising tool for monitoring and controlling the target insect as part of a synergistic approach.  相似文献   
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