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1.
Electromagn Biol Med ; 37(2): 66-75, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29667447

RESUMO

The aim of this study was to investigate effect of radiofrequency radiation (RFR) emitted from mobile phones on DNA damage in follicle cells of hair in the ear canal. The study was carried out on 56 men (age range: 30-60 years old)in four treatment groups with n = 14 in each group. The groups were defined as follows: people who did not use a mobile phone (Control), people use mobile phones for 0-30 min/day (second group), people use mobile phones for 30-60 min/day (third group) and people use mobile phones for more than 60 min/day (fourth group). Ear canal hair follicle cells taken from the subjects were analyzed by the Comet Assay to determine DNA damages. The Comet Assay parameters measured were head length, tail length, comet length, percentage of head DNA, tail DNA percentage, tail moment, and Olive tail moment. Results of the study showed that DNA damage indicators were higher in the RFR exposure groups than in the control subjects. In addition, DNA damage increased with the daily duration of exposure. In conclusion, RFR emitted from mobile phones has a potential to produce DNA damage in follicle cells of hair in the ear canal. Therefore, mobile phone users have to pay more attention when using wireless phones.


Assuntos
Telefone Celular , Dano ao DNA , Meato Acústico Externo/citologia , Campos Eletromagnéticos/efeitos adversos , Folículo Piloso/citologia , Folículo Piloso/efeitos da radiação , Folículo Piloso/metabolismo , Humanos , Ondas de Rádio/efeitos adversos , Fatores de Tempo
2.
Proc Natl Acad Sci U S A ; 113(17): 4706-10, 2016 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-27071131

RESUMO

Plants use light for photosynthesis and for various signaling purposes. The UV wavelengths in sunlight also introduce DNA damage in the form of cyclobutane pyrimidine dimers (CPDs) and pyrimidine (6-4) pyrimidone photoproducts [(6-4)PPs] that must be repaired for the survival of the plant. Genome sequencing has revealed the presence of genes for both CPD and (6-4)PP photolyases, as well as genes for nucleotide excision repair in plants, such as Arabidopsis and rice. Plant photolyases have been purified, characterized, and have been shown to play an important role in plant survival. In contrast, even though nucleotide excision repair gene homologs have been found in plants, the mechanism of nucleotide excision repair has not been investigated. Here we used the in vivo excision repair assay developed in our laboratory to demonstrate that Arabidopsis removes CPDs and (6-4)PPs by a dual-incision mechanism that is essentially identical to the mechanism of dual incisions in humans and other eukaryotes, in which oligonucleotides with a mean length of 26-27 nucleotides are removed by incising ∼20 phosphodiester bonds 5' and 5 phosphodiester bonds 3' to the photoproduct.


Assuntos
Dano ao DNA/genética , Reparo do DNA/genética , DNA de Plantas/genética , DNA de Plantas/efeitos da radiação , Desoxirribodipirimidina Fotoliase/genética , Dímeros de Pirimidina/genética , Arabidopsis/genética , Arabidopsis/efeitos da radiação , Linhagem Celular , Reparo do DNA/efeitos da radiação , Desoxirribodipirimidina Fotoliase/efeitos da radiação , Relação Dose-Resposta à Radiação , Dímeros de Pirimidina/efeitos da radiação , Pirimidinonas/efeitos da radiação , Doses de Radiação , Raios Ultravioleta
3.
Nutr Cancer ; 68(3): 481-94, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27008095

RESUMO

The aim of this study was to investigate whether cinnamon bark oil (CBO) has protective effect on taxanes-induced adverse changes in sperm quality, testicular and epididymal oxidant/antioxidant balance, testicular apoptosis, and sperm DNA integrity. For this purpose, 88 adult male rats were equally divided into 8 groups: control, CBO, docetaxel (DTX), paclitaxel (PTX), DTX+PTX, DTX+CBO, PTX+CBO, and DTX+PTX+CBO. CBO was given by gavage daily for 10 weeks at the dose of 100 mg/kg. DTX and PTX were administered by intraperitoneal injection at the doses of 5 and 4 mg/kg/week, respectively, for 10 weeks. DTX+PTX and DTX+PTX+CBO groups were treated with DTX during first 5 weeks and PTX during next 5 weeks. DTX, PTX, and their mixed administrations caused significant decreases in absolute and relative weights of all reproductive organs, testosterone level, sperm motility, concentration, glutathione level, and catalase activity in testicular and epididymal tissues. They also significantly increased abnormal sperm rate, testicular and epididymal malondialdehyde level, apoptotic germ cell number, and sperm DNA fragmentation and significantly damaged the histological structure of testes. CBO consumption by DTX-, PTX-, and DTX+PTX-treated rats provided significant ameliorations in decreased relative weights of reproductive organs, decreased testosterone, decreased sperm quality, imbalanced oxidant/antioxidant system, increased apoptotic germ cell number, rate of sperm with fragmented DNA, and severity of testicular histopathological lesions induced by taxanes. In conclusion, taxanes cause impairments in sperm quality, testicular and epididymal oxidant/antioxidant balance, testicular histopathological structure, and sperm DNA integrity, and long-term CBO consumption protects male reproductive system of rats.


Assuntos
Epididimo/efeitos dos fármacos , Óleos Voláteis/farmacologia , Paclitaxel/efeitos adversos , Espermatozoides/efeitos dos fármacos , Taxoides/efeitos adversos , Testículo/efeitos dos fármacos , Animais , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Biomarcadores/metabolismo , Cinnamomum zeylanicum/química , Fragmentação do DNA/efeitos dos fármacos , Docetaxel , Epididimo/patologia , Masculino , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Ratos Wistar , Espermatozoides/fisiologia , Testículo/patologia , Testosterona/sangue
4.
J Chem Neuroanat ; 75(Pt B): 116-22, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26775760

RESUMO

Wireless internet (Wi-Fi) providers have become essential in our daily lives, as wireless technology is evolving at a dizzying pace. Although there are different frequency generators, one of the most commonly used Wi-Fi devices are 2.4GHz frequency generators. These devices are heavily used in all areas of life but the effect of radiofrequency (RF) radiation emission on users is generally ignored. Yet, an increasing share of the public expresses concern on this issue. Therefore, this study intends to respond to the growing public concern. The purpose of this study is to reveal whether long term exposure of 2.4GHz frequency RF radiation will cause DNA damage of different tissues such as brain, kidney, liver, and skin tissue and testicular tissues of rats. The study was conducted on 16 adult male Wistar-Albino rats. The rats in the experimental group (n=8) were exposed to 2.4GHz frequency radiation for over a year. The rats in the sham control group (n=8) were subjected to the same experimental conditions except the Wi-Fi generator was turned off. After the exposure period was complete the possible DNA damage on the rat's brain, liver, kidney, skin, and testicular tissues was detected through the single cell gel electrophoresis assay (comet) method. The amount of DNA damage was measured as percentage tail DNA value. Based on the DNA damage results determined by the single cell gel electrophoresis (Comet) method, it was found that the% tail DNA values of the brain, kidney, liver, and skin tissues of the rats in the experimental group increased more than those in the control group. The increase of the DNA damage in all tissues was not significant (p>0.05). However the increase of the DNA damage in rat testes tissue was significant (p<0.01). In conclusion, long-term exposure to 2.4GHz RF radiation (Wi-Fi) does not cause DNA damage of the organs investigated in this study except testes. The results of this study indicated that testes are more sensitive organ to RF radiation.


Assuntos
Encéfalo/efeitos da radiação , Dano ao DNA/efeitos da radiação , Ondas de Rádio/efeitos adversos , Testículo/efeitos da radiação , Tecnologia sem Fio , Animais , Encéfalo/metabolismo , Dano ao DNA/fisiologia , Rim/metabolismo , Rim/efeitos da radiação , Fígado/metabolismo , Fígado/efeitos da radiação , Masculino , Ratos , Ratos Wistar , Pele/metabolismo , Pele/efeitos da radiação , Testículo/metabolismo
5.
Cryobiology ; 68(3): 349-53, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24759298

RESUMO

This study was designed to evaluate the in vitro effects of l-carnitine and glutamine (Gln) on the sperm quality parameters of liquid-stored rabbit semen maintained up to 24 h at 5°C. Pooled and extended ejaculates were divided into two equal portions. l-Carnitine doses of 0.5, 1 and 2mM were added to the first portion, and glutamine was added at the same doses to the second portion. All samples were cooled to 5°C and examined at 0, 6, 12 and 24 h of liquid storage. Supplementation of the semen extender with three different doses of l-carnitine provided significant increases in the percentage of motile sperm at 12 h (P<0.01), and 24h (P<0.001) and enabled significant protection of the sperm plasma membrane (P<0.01) at 12 and 24h of cool-storage, in comparison to the control samples. Only the 2mM dose of l-carnitine significantly (P<0.01) decreased the rate of acrosomal damage when compared to the control group. Furthermore, all doses of Gln caused a significant (P<0.01) decrease in acrosomal damage at 6h, and provided significant improvement (P<0.01) in sperm motility, acrosomal and plasma membrane integrities at 12 and 24h of liquid storage, when compared to the controls. In conclusion, the supplementation of liquid-stored rabbit semen with l-carnitine and Gln provided a protection for sperm against cool storage-induced functional and structural damages.


Assuntos
Carnitina/metabolismo , Glutamina/metabolismo , Substâncias Protetoras/metabolismo , Coelhos , Preservação do Sêmen/veterinária , Espermatozoides/citologia , Animais , Membrana Celular/metabolismo , Masculino , Coelhos/metabolismo , Preservação do Sêmen/métodos , Motilidade dos Espermatozoides , Espermatozoides/metabolismo
6.
Cryobiology ; 68(1): 129-33, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24468272

RESUMO

Supplementation of the semen extender with antioxidants did not produce any significant effect on CASA and progressive motilities and sperm motility characteristics, in comparison to the control group (P > 0.05). For sperm acrosome and total abnormalities, TCM-199 supplemented with cysteine (2.60 ± 0.24% and 4.80 ± 0.20%), glutamine (2.80 ± 0.20% and 6.40 ± 0.40%), carnitine (2.60 ± 0.24% and 6.00 ± 0.63%) and methionine (3.40 ± 0.51% and 9.20 ± 0.86%) at doses of 2 mM provided a better protective effect, compared to that of the controls (8.00 ± 0.44 and 15.60 ± 1.895). As regards sperm membrane integrity, supplementation with 2 mM of glutamine and methionine (56.00 ± 1.70% and 62.40 ± 1.78%, respectively) resulted in higher rates, when compared to the control group (41.40 ± 4.74%). According to the results of the COMET assay, only the use of TCM-199 supplemented with 2 mM of cysteine reduced DNA damage and resulted in percentages of sperm with damaged DNA (2.17 ± 0.18%) lower than those of the control group (3.16 ± 0.32%) (P < 0.001). For pregnancy rates, there were no significant differences among the extender groups (P > 0.05).


Assuntos
Antioxidantes/farmacologia , Criopreservação , Cisteína/farmacologia , Preservação do Sêmen/métodos , Espermatozoides/efeitos dos fármacos , Animais , Carnitina/farmacologia , Bovinos , Crioprotetores/farmacologia , Fragmentação do DNA/efeitos dos fármacos , Feminino , Fertilização/efeitos dos fármacos , Fertilização/fisiologia , Glutamina/farmacologia , Masculino , Metionina/farmacologia , Gravidez , Motilidade dos Espermatozoides/efeitos dos fármacos , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/fisiologia
7.
Cryobiology ; 67(1): 1-6, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23597426

RESUMO

The aim of the present study was to determine the effects of the bovine serum albumin (BSA) and fetal calf serum (FCS) on sperm quality, DNA fragmentation and lipid peroxidation of liquid stored rabbit semen stored up to 72 h at 5 °C. Ejaculates were collected from five New Zealand male rabbits by artificial vagina and pooled at 37 °C following evaluation. Each pooled ejaculate was split into three equal experimental groups and diluted to a final concentration of approximately 40 × 10(6)sperm/ml (single step dilution), in an Eppendorf tube, with the Tris based extender containing BSA (5mg/ml), FCS (10%) or no additive (control) at 37 °C, cooled to 5 °C and stored for up to 72 h. The extender supplemented with BSA and FCS did not improve the percentages of motility and acrosomal abnormality during 48 h compared to the control. The additives BSA and FCS had a significant effect in the maintaining of plasma membrane integrity between 48 and 72 h storage period, compared to the control (P<0.01). The supplementation of BSA and FCS had a protective effect on motility (P<0.05), plasma membrane integrity (P<0.01) and acrosomal integrity (P<0.01) at 72 h compared to the control. The supplementations with BSA and FCS led to a reduction in DNA damage of rabbit sperm at 48 and 72 h during storage period, compared to the control (P<0.001). Although supplementation of BSA and FCS caused significant (P<0.01) decreases in malondialdehyde (MDA) level at 48 h and 72 h, they significantly (P<0.01) increased the glutathione peroxidase (GPx) antioxidant activity up to 72 h when compared to the control group. In conclusion, BSA and FCS supplementation to liquid stored rabbit semen provide a protection for spermatozoa against cool storage-induced DNA damage and plasma membrane integrity by their antioxidative properties.


Assuntos
Criopreservação/veterinária , Preservação do Sêmen/veterinária , Soroalbumina Bovina/farmacologia , Soro , Espermatozoides/efeitos dos fármacos , Animais , Bovinos , Membrana Celular/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Glutationa Peroxidase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Malondialdeído/metabolismo , Coelhos , Sêmen/efeitos dos fármacos , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/fisiologia
8.
Cryobiology ; 65(2): 93-7, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22634115

RESUMO

This study evaluated the protective effects of supplementation with three different sugars on the motility, morphology and DNA integrity of rat epididymal sperm chilled and stored at 4°C Epididymides were obtained from each donor. Rat epididymal sperm was diluted in Ham's F10 plus raffinose, Ham's F10 plus trehalose, Ham's F10 plus fructose, and Ham's F10 medium for control purposes. Thereafter, the extended sperm were chilled and stored in liquid form at 4°C. Sperm motility, morphological abnormalities and DNA damage were determined at 0 and 12h after chilling. No significant difference was observed in any of the parameters evaluated at 0h, before storage (P>0.05). After 12h of storage, all sugar additives led to statistically higher motility, normal sperm morphology and DNA integrity in comparison to the control group. Raffinose gave the best motility percentages (32.86±1.84%) after 12h of storage at 4°C, compared to the other groups (P<0.001). In conclusion, Raffinose, trehalose and fructose provided a better protection of sperm functional parameters against chilling injury, in comparison to the control group.


Assuntos
Epididimo/citologia , Preservação do Sêmen/métodos , Preservação do Sêmen/veterinária , Espermatozoides/citologia , Animais , Temperatura Baixa , Ensaio Cometa , DNA/genética , Dano ao DNA , Epididimo/metabolismo , Frutose/metabolismo , Masculino , Rafinose/metabolismo , Ratos , Ratos Wistar , Motilidade dos Espermatozoides , Espermatozoides/metabolismo , Trealose/metabolismo
9.
Theriogenology ; 75(8): 1459-65, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21354604

RESUMO

The objective of this study was to evaluate the effects of the addition of different sugars (raffinose, sucrose, and trehalose) on bull spermatozoa cryopreserved in a commercial extender (Optidyl) supplemented with glutamine on semen parameters, fertilizing ability and superoxide dismutase (SOD) activity. Nine ejaculates for each bull were used in the study. Semen was frozen in five different extenders: raffinose 25 mM plus glutamine 3 mM (RGO), sucrose 25 mM plus glutamine 3 mM (SGO), trehalose 25 mM plus glutamine 3 mM (TGO), glutamine 3 mM (GO) and control (O). Insemination doses were processed so that each 0.25 mL straw contained 15 x 10(6)sperm. Groups of GO and RGO resulted in the higher rates of subjective (54.0 ± 1.7% and 64.0 ± 1.1%; P < 0.01) and CASA motilities (53.0 ± 2.7% and 61.0 ± 4.4%; P < 0.001), respectively compared to the other groups. The supplementation of additives did not provide an effect on the level of post-thaw sperm CASA progressive motilities, the sperm motion characteristics and pregnancy rates. GO and RGO provided the better protective effect for sperm acrosome (4.0 ± 0.5% and 12.0 ± 0.6%) and total abnormalities (5.0 ± 0.3% and 13.0 ± 0.7%; P < 0.001), respectively. At the HOST values, the additives did not give to result the protective effect in comparison to Optydil extender without additives (P > 0.05). For pregnancy rates, there were no significant differences among the groups. The supplementation of additives did not provide any significant difference on the level of SOD activity (P > 0.05). It can be also thought that these sugars might have worked with glutamine in a synergy. Thereby, sugars such as raffinose and sucrose with glutamine in freezing extender may be recommended to facilitate bull semen freezability.


Assuntos
Carboidratos/farmacologia , Criopreservação/veterinária , Glutamina/farmacologia , Preservação do Sêmen/veterinária , Espermatozoides/efeitos dos fármacos , Espermatozoides/fisiologia , Animais , Bovinos , Feminino , Congelamento , Masculino , Gravidez , Espermatozoides/enzimologia , Superóxido Dismutase/metabolismo
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