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3.
Biology (Basel) ; 12(2)2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36829585

RESUMO

Exposure to electromagnetic radiation (EMR) from intermediate frequency sources has increased exponentially in recent years. The consequences of this exposure on biological systems are prompting scientists to study the effects on human health. This current study aimed to determine the effects of intermediate frequency (150 kHz) EMR exposure on the vital organs of female Sprague Dawley rats. The EMR group (n = 10 animals) was exposed to a frequency of 150 kHz with an intensity of 65 ± 15 µW/cm2 for two months. The control group (n = 10 animals) was exposed to an intensity of 35 ± 15 nW/cm2. Haematological, histochemical, gross, and histopathological profiles of all major organs of all animals were then performed using standard procedures. All major organs generally showed no significant detectable effects in either the control or EMR groups. However, gross and histopathological examinations revealed the effects of EMR on the liver and lungs, which showed inflammatory changes without significant biochemical/haematological manifestations. In addition, a significant increase in serum sodium level and a decrease in serum urea level were also observed in the EMR group. It can be concluded that the current frequency and duration of exposure trigger the changes in the liver and lungs but are not sufficient to cause clinical and functional manifestations. Therefore, a long-term exposure study might be helpful to determine the effects of 150 kHz IF EMR on these organs.

4.
Heliyon ; 8(12): e12228, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36578412

RESUMO

Background: The present study aimed to evaluate the effects of whole-body exposure to 150 kHz Intermediate-frequency electromagnetic radiation (IF EMR) on fertility indicators of male rats since human exposure to this frequency has increased in recent years. Fourteen adult male Sprague-Dawley rats were used in this study. The rats were randomly divided into a control and an EMR group (n = 7/group). The EMR group was continuously irradiated with 150 kHz EMR for 8 weeks. Male fertility indicators, body mass, testicular mass, rectal temperature, testicular histology, histometry, sperm analysis, and serum gonadotrophic hormone levels were evaluated. Results: The study showed no negative effect on body mass (grams) (323.78 ± 37.09 to 305.09 ± 26.36; p = 0.72), rectal temperature (Control: 34.5 °C-35.8 °C; EMR: 34.4 °C-36.1 °C; p < 0.05), and testicular histology. There were significant reductions in left and right testicular mass (1.04 ± 0.10 to 0.96 ± 0.32: p = 0.03 and 1.02 ± 0.08 to 0.96 ± 0.35 p = 0.04, respectively), interstitial cell count/1000 µm2 (5.33 ± 0.56 to 4.47 ± 0.48; p = 0.01), sperm motility trajectories (p = 0.05) and sperm distal cytoplasmic droplet (%) (2.27 ± 2.28 to 6.84 ± 5.01; p = 0.05). A significant increase in follicle-stimulating hormone levels was observed (13.44 ± 6.38 IU/ml to 26.96 ± 8.07 IU/ml; p = 0.01). Conclusions: Most male fertility parameters of rats in the present study were not affected by 8 weeks of whole-body exposure to 150 kHz EMR. However, significant decreases in testicular mass, interstitial cell count/1000 µm2, sperm motility trajectories, and distal cytoplasmic droplets were observed, as well as an increase in FSH level.

5.
Br J Radiol ; 95(1136): 20201289, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35616646

RESUMO

Modern conformal radiation therapy using techniques such as modulation, image guidance and motion management have changed the face of radiotherapy today offering superior conformity, efficiency, and reproducibility to clinics worldwide. This review assesses the impact of these advanced radiotherapy techniques on patient toxicity and survival rates reported from January 2017 to September 2020. The main aims are to establish if dosimetric and efficiency gains correlate with improved survival and reduced toxicities and to answer the question 'What is the clinical evidence for the most effective implementation of VMAT?'. Compared with 3DCRT, improvements have been reported with VMAT in prostate, locally advanced cervical carcinoma and various head and neck applications, leading to the shift in technology to VMAT. Other sites such as thoracic neoplasms and nasopharyngeal carcinomas have observed some improvement with VMAT although not in line with improved dosimetric measures, and the burden of toxicity and the incidence of cancer related deaths remain high, signaling the need to further mitigate toxicity and increase survival. As technological advancement continues, large randomised long-term clinical trials are required to determine the way-forward and offer site-specific recommendations. These studies are usually expensive and time consuming, therefore utilising pooled real-world data in a prospective nature can be an alternative solution to comprehensively assess the efficacy of modern radiotherapy techniques.


Assuntos
Radioterapia de Intensidade Modulada , Humanos , Masculino , Órgãos em Risco , Estudos Prospectivos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Reprodutibilidade dos Testes
6.
J Ovarian Res ; 14(1): 173, 2021 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-34895279

RESUMO

INTRODUCTION: The hypothalamic-pituitary-ovarian (HPO) axis is the principal regulator of the reproductive system. The neurons in the arcuate nucleus of the hypothalamus signal the basophilic cells of the anterior pituitary to release luteinizing hormone (LH) and follicle stimulating hormone (FSH), which bind to the granulosa and theca cells of a follicle in the ovary to promote healthy follicular development. Disruption of this process at any time can lead to polycystic ovaries and, if left untreated, can lead to Polycystic Ovarian Syndrome (PCOS), one of the leading causes of infertility. A novel treatment option using 150 kHz Intermediate Frequency (IF) Electromagnetic Radiation (EMR) has been proposed to monitor the effect of this frequency during cystic development. METHODS: To prove this, an experiment was conducted to study the effect of whole-body exposure to 150 kHz EMR for 8 weeks at receptor, cellular, tissue and hormonal levels on the HPO axis of 25 young cyclic female rats. RESULTS: The results showed that 150 kHz EMR did not affect the histoarchitecture of neurons of arcuate nucleus of the hypothalamus of PCO-induced rats. It was also found that the number of basophilic cells of the pituitary gland was increased and the immunoreactivity of LH and FSH secretion increased. This EMR field also decreased the development of follicular cysts in the ovary and possibly increased the immunoreactivity of the LH and FSH receptors as well on the theca and granulosa cells of follicles in the ovary. CONCLUSION: There are still many limitations to this study. If properly evaluated, the results of this experiment could help develop a new non-invasive treatment option for women with PCOS in the near future.


Assuntos
Magnetoterapia , Síndrome do Ovário Policístico/terapia , Animais , Modelos Animais de Doenças , Radiação Eletromagnética , Estradiol , Feminino , Hormônio Foliculoestimulante/sangue , Hormônio Foliculoestimulante/metabolismo , Hipotálamo/metabolismo , Hipotálamo/patologia , Hormônio Luteinizante/sangue , Hormônio Luteinizante/metabolismo , Neurônios/citologia , Ovário/metabolismo , Ovário/patologia , Hipófise/metabolismo , Hipófise/patologia , Síndrome do Ovário Policístico/induzido quimicamente , Síndrome do Ovário Policístico/metabolismo , Síndrome do Ovário Policístico/patologia , Ratos Sprague-Dawley , Receptores do FSH/metabolismo , Receptores do LH/metabolismo
7.
J Ovarian Res ; 14(1): 26, 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33546719

RESUMO

BACKGROUND: Polycystic ovary syndrome (PCOS) is the most common complex endocrine disorder affecting approximately 2-20% of reproductive aged females. Tumour Treating Fields (100-300 kHz) is a recent innovative, non-invasive therapeutic approach to cancer therapy. This frequency as an alternative therapy for the management of polycystic ovaries has not yet been explored. OBJECTIVES: To explore the effect of full-body exposure of 150 kHz Electromagnetic Radiation (EMR), on the development of polycystic ovaries in an estradiol valerate-induced PCO rat model. METHOD: Twenty-one female adult rats were divided into three groups (n = 7 each): control, Estradiol Valerate (EV) and EV + EMR groups. The EV + EMR group was subjected to full body exposure at 150 kHz EMR continuously for eight consecutive weeks. Estradiol valerate was administered orally to induce polycystic ovaries in EV and EV + EMR groups. Body and ovarian weights were recorded and analysed. The regularity of the estrous cycle was assessed in all three groups. The histological study of ovarian tissue was carried out by haematoxylin and eosin staining. The serum concentration levels of Luteinizing Hormone (LH), Follicle-Stimulating Hormone (FSH) and testosterone were measured using the ELISA method. RESULTS: The body and ovary weights did not differ significantly between the EV and EV + EMR groups. The estrous cycle was found to be irregular in both the EV and EV + EMR groups. Ovarian histology revealed near normal morphology with little or no degenerative and morphological changes in developing follicles in the exposed group. Histometrical analysis showed an increased number of developing follicles and a significant reduction in the number and size of follicular cysts (p < 0.05) in the EV + EMR group. Hormonal analysis revealed no significant difference in the testosterone and FSH levels between the EV + EMR and EV groups. However, the LH, LH/FSH ratio decreased significantly in the EV + EMR group compares to the EV group. CONCLUSION: The 150 kHz EMR appear to have little or no degenerative and morphological changes in the developing follicles, an increased number of typical developing follicles and a significant reduction in the number and size of the follicular cysts (p < 0.05).


Assuntos
Radiação Eletromagnética , Ciclo Estral/efeitos da radiação , Folículo Ovariano/efeitos da radiação , Ovário/efeitos da radiação , Síndrome do Ovário Policístico/patologia , Animais , Peso Corporal , Modelos Animais de Doenças , Estradiol/toxicidade , Estrogênios/toxicidade , Ciclo Estral/efeitos dos fármacos , Feminino , Hormônio Foliculoestimulante/sangue , Hormônio Luteinizante/sangue , Tamanho do Órgão , Folículo Ovariano/efeitos dos fármacos , Ovário/efeitos dos fármacos , Ovário/patologia , Síndrome do Ovário Policístico/sangue , Síndrome do Ovário Policístico/induzido quimicamente , Síndrome do Ovário Policístico/radioterapia , Ratos , Ratos Sprague-Dawley , Testosterona/sangue
8.
Radiat Res ; 175(3): 322-7, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21388275

RESUMO

Exposure to high doses of ionizing radiation unequivocally produces adverse health effects including malignancy. At low doses the situation is much less clear, because effects are generally too small to be estimated directly by epidemiology, and extrapolation of risk and establishment of international rules and standards rely on the linear no-threshold (LNT) concept. Claims that low doses are more damaging than would be expected from LNT have been made on the basis of in vitro studies of nontargeted bystander effects and genomic instability, but relevant investigations of primary cells and tissues are limited. Here we show that after low-dose low-LET in vivo radiation exposures in the 0-100-mGy range of murine bone marrow there is no evidence of a bystander effect, assessed by p53 pathway signaling, nor is there any evidence for longer-term chromosomal instability in the bone marrow at doses below 1000 mGy. The data are not consistent with speculations based on in vitro nontargeted effects that low-dose X radiation is more damaging than would be expected from linear extrapolation.


Assuntos
Células da Medula Óssea/efeitos da radiação , Doses de Radiação , Animais , Apoptose/efeitos da radiação , Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Efeito Espectador/efeitos da radiação , Instabilidade Cromossômica/efeitos da radiação , Relação Dose-Resposta à Radiação , Transferência Linear de Energia , Camundongos , Transdução de Sinais/efeitos da radiação , Estresse Fisiológico/efeitos da radiação , Fatores de Tempo , Proteína Supressora de Tumor p53/metabolismo , Raios X
9.
Int J Radiat Biol ; 81(12): 929-36, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16524848

RESUMO

PURPOSE: To determine the role of single (SSB) and double strand break (DSB) repair in the induction and propagation of radiation-induced instability. MATERIALS AND METHODS: Two defined hamster cell lines with known DNA repair deficiencies in DSB repair (XR-C1) and base excision repair (EM-C11) and the parental wild-type line (CHO-9) were used. The rate of micronucleus formation, apoptosis and survival were measured at 0, 7 and 14 days after X-ray radiation. RESULTS: An enhanced rate of production of damaged cells was observed in wild type and the repair deficient mutants after irradiation. This was cell type, dose and time-dependent. All cells demonstrated delayed death up to day 14 after irradiation along with an elevated apoptosis frequency. The yield of micronuclei was not significantly increased in the wild-type cells, but was in the mutant cells, over the dose and time range studied. For all three endpoints the increase in damage was most pronounced in the SSB deficient cell line. CONCLUSIONS: SSB and/or oxidized base damage play a major role, rather than DSB, in radiation induced instability.


Assuntos
Reparo do DNA/genética , Instabilidade Genômica/efeitos da radiação , Estresse Oxidativo , Lesões por Radiação/genética , Animais , Apoptose , Células CHO , Morte Celular , Cricetinae , DNA , DNA de Cadeia Simples , Testes para Micronúcleos
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