Drosophila melanogaster (Oregon-R, Oak Ridge strain) males, 19 to 21 hours old, were X-rayed with a total dose of 1000r. or 3000 r. given in two equal fractions of 500 r. or 1500 r. at a dose rate of 500r. per minute, except for Experiment #2 in which they were given a single dose of 1000 r. at 24 +/- 1 degree C in several gas environments, with a time interval of 40 minutes between the two doses. At each Change of gas(es),the system was evacuated to remove all gases, then Hushed with helium for 1 minute. Tests using CO were carried out in the dark and the others m the light, both at 1 atmosphere of the gas or gas mixture. In order to study the genetic radiation damage and its modification by several gases the frequencies of dominant lethals and translocations induced in cells which were in different stages of spermatogenesis were scored using seven sequential 2-day mating over a two-week test period. Data are prtsented which indicate that: 1) The frequency of dominant lethals increased from sperm to spermatids and meiotic cells, then decreased in spermatogonial cells which were the least susceptible to X-rays. 2) The cycle of damage for dominant lethals is similar to that for translocations, but does not coincide with it completely, and the peaks of damage for both are located in the early postmeiotic stages, and the cycle of frequencies of translocations coincides with that of percentages of sterility of F1 the coincidence frequencies between translocations and the sterility demonstrates that the mechanisms of damage for both are related, at least in part. 3) The NO effect on sperm and late spermatids is more drastic than the oxygen effect, but a major fraction of the effect is to cause the death of the sperm. 4) The carbon monoxide (CO) during radiation increase genetic damage above the other gases tested, and it is possible to conclude that the duration(s) of 4 minutes of gases in post-treatments is too short to modify the damage. 5) There are few (or no) translocations recovered from premeiotic cells. 6) The Y-chromosome was involved in 10.8% of total breaks, or about 1/4 as frequently as the two autosomes tested, and chromosomes 2 and 3 equally participated in an interchange.
Animal ; Chromosome Aberrations/radiation effects ; Drosophila ; Male ; Meiosis/radiation effects* ; Radiation Genetics* ; Spermatozoa/radiation effects* ; Time Factors

OBJECTIVETo investigate the influences of mobile phone radiation on the quality and DNA methylation of human sperm in vitro.

METHODSAccording to the fifth edition of the WHO Laboratory Manual for the Examination and Processing of Human Semen, we randomly selected 97 male volunteers with normal semen parameters and divided each semen sample from the subjects into two equal parts, one exposed to mobile phone radiation at 1950 M Hz, SAR3. 0 W/kg for 3 hours while the other left untreated as the control. We obtained routine semen parameters as well as the acrosomal reaction ability, apoptosis and DNA methylation of sperm, and compared them between the two groups.

RESULTSCompared with the control, the radiation group showed significantly decreased progressive sperm motility ([36.64 ± 16.93] vs [27.56 ± 16.92]%, P < 0.01) and sperm viability ([63.72 ± 16.35] vs [54.31 ± 17.35]%, P < 0.01) and increased sperm head defects ([69.92 ± 4.46] vs [71.17 ± 4.89]%, P < 0.05), but no significant differences in sperm acrosomal reaction ([66.20 ± 6.75] vs [64.50 ± 3.47]%, P > 0.05). The early apoptosis rate of sperm cells was remarkably higher in the radiation group ([6.89 ± 9.84]%) than in the control ([4.44 ± 5.89]%) (P < 0.05). However, no statistically significant differences were found between the control and radiation groups in the DNA methylation patterns of the paternal imprinting gene H19 ICR ([0.60 ± 0.02] vs [1.40 ± 0.03]%, P > 0.05) or the maternal imprinting gene KvDMR1 ([0.00 ± 0.00] vs [1.80 ± 0.031%, P > 0.05).

CONCLUSIONMobile phone radiation reduces the progressive motility and viability of human sperm and increases sperm head defects and early apoptosis of sperm cells.

Cell Phone ; DNA Methylation ; radiation effects ; Humans ; In Vitro Techniques ; Male ; Semen ; radiation effects ; Semen Analysis ; Sperm Head ; radiation effects ; Sperm Motility ; radiation effects ; Spermatozoa ; cytology ; radiation effects

OBJECTIVETo study the effect of high power microwave (HPM) radiation on the testicular germ cell apoptosis.

METHODSOne hundred and twenty-five Spraque-Dawley rats were randomly divided into two groups, unexposed control group and experimental group(further divided into four subgroups: 10 mW/cm2 5 min, 10 mW/cm2 10 min, 20 mw/cm2 5 min, and 20 mW/cm2 10 min), and then the experimental group was radiated with S wave band of 10 mW/cm2, 20 mW/cm2 high power microwave for 5 or 10 min. Testicular samples were taken at 6 h, 24 h, 48 h, 72 h and 5 d after radiation and separately studied. At the end of the process, testicular germ cell apoptosis was detected by in situ terminal deoxynucleotityl transferase mediated dUTP nick end labeling (TUNEL).

RESULTSThe number of apoptotic cells of the 6 h, 24 h and 48 h experimental groups at 5 min after 10 and 20 mW/cm2 radiation was remarkably larger than that of the controls (P < 0.01), especially after 10 mW/cm2 radiation, the number of the 6 h group reached the peak (161.27 +/- 5.90) /5 convoluted seminiferous tubules. The changes in the other experimental groups had no significant difference compared with the controls (P > 0.05).

CONCLUSIONHPM can increase germ cell apoptosis of the rat testis, which is related to the time of radiation and sample acquisition. In the condition of the present test, 5 minutes of HPM radiation may significantly enhance testicular germ cell apoptosis and damage, which in turn may influence the reproductive function of the rats.

Animals ; Apoptosis ; radiation effects ; Male ; Microwaves ; Rats ; Rats, Sprague-Dawley ; Spermatozoa ; pathology ; radiation effects ; Testis ; radiation effects

OBJECTIVETo explore the pathological characteristics and the dynamic change regularity of the testis induced by high power microwave (HPM) radiation.

METHODSOne hundred and sixty-five male Wistar rats were exposed to 0, 3, 10, 30 and 100 mW/cm2 HPM radiation for five minutes, and changes of testicular morphology and teratogenic ratio of epididymal spermatozoa were observed through light microscope and electron microscope at 6 h, 1, 3, 7, 14, 28 and 90 d after radiation.

RESULTSInjury of testicular spermatogenic cells in rats might be induced by 3 to approximately 100 mW/cm2 HPM radiation, and the main pathological changes were degeneration, necrosis, shedding of spermatogenic cells, formation of multinuclear giant cells, decrease or loss of sperm and interstitial edema. Injury of spermatogenic cells underwent such phases as death and shedding, cavitation, regeneration and repair, characterized by being focalized, inhomogenous and phased. And the severity of pathological changes of the testis increased with power density. There was only scattered degeneration, necrosis, shedding of spermatogenic cells in the seminiferous tubule one day after 3 mW/cm2 radiation, and the pathological changes six hours after 10 mW/cm2 radiation was similar to those one day after 3 mW/cm2 radiation, but with the formation of multinuclear giant cells, and the above-mentioned pathological changes aggravated from one day to seven days after radiation. There was a significant increase in degeneration, necrosis, shedding of spermatogenic cells, as well as a significant decrease in spermatozoa and focal necrosis in simple seminiferous tubules six hours after 30 and 100 mW/cm2 radiation, and the subsequent changes were similar to those of 10 mW/cm2 radiation. There was a significant increase in teratogenic ratio of epididymal spermatozoa at 3 d, 1 to approximately 7 d, 6 h to approximately 7 d after 3, 10, 30 and 100 mW/cm2 microwave radiation respectively (P < 0.01 or P < 0.05).

CONCLUSIONHPM radiation may cause injury of testicular spermatogenic cells in rats, which has a positive correlation to radiation dosage and time.

Animals ; Dose-Response Relationship, Radiation ; Male ; Microwaves ; Rats ; Rats, Wistar ; Spermatozoa ; pathology ; radiation effects ; Testis ; pathology ; radiation effects

OBJECTIVETo investigate the effects of extremely low frequency electromagnetic fields (ELF EMFs) on male reproduction in mice.

METHODS94 adult male mice were exposed to 50 Hz sinusoidal electromagnetic fields of 0.2, 3.2 or 6.4 mT for 2 weeks or 4 weeks. Testicular histology and weight, sperm amount, sperm motility and morphology were measured. The percentages of different ploidy cells and cell phases, and DNA content of testis cells were estimated by flow cytometry. The micronucleus rate of bone-marrow cell was also observed.

RESULTSThe testicular weight of the mice exposed to 6.4 mT for 4 weeks [(76.06 +/- 32.25) mg] was significantly lower than that of the control [(111.44 +/- 19.99) mg, P < 0.05]; no significant histopathological changes were observed on the testis in EMFs exposed mice;the sperm amount was decreased after EMFs exposure for 4 weeks, and those of the mice exposed to 0.2 mT and 6.4 mT for 4 weeks [(4.87 +/- 0.94) x 10(6)/ml and (4.30 +/- 1.89) x 10(6)/ml respectively] were significantly lower than that of the control [(6.67 +/- 0.70) x 10(6)/ml, P < 0.05]; the rates of sperm motility also showed a decline. After 0.2, 3.2 or 6.4 mT EMFs exposure for 2 weeks, the deformity rates of sperm [(7.416 +/- 3.352)%, (6.862 +/- 2.947)% and (8.112 +/- 4.615)% respectively] were significantly higher than that of the control [(4.098 +/- 2.028)%, P < 0.01]. Similarly, those of the mice exposed for 4 weeks [(10.267 +/- 3.836)%, (11.027 +/- 7.059)%, (8.814 +/- 3.678)% respectively] were higher than that of the control [(3.714 +/- 1.830)%]. After 6.4 mT exposure for 2 weeks, the percentages of 1C testis cells [(69.56 +/- 4.07)%] was significantly lower than that of the control [(73.45 +/- 3.10)%, P < 0.05]. There were not any remarkable changes in those of 2C, 4C cells. DNA content in different ploidy cells of the mice exposed to 6.4 mT was decreased. Moreover, the cell percentage in S phase was increased significantly (P < 0.01).

CONCLUSIONELF EMFs exposure may have some adverse effects on reproduction in mice.

Animals ; DNA ; metabolism ; Electromagnetic Fields ; Male ; Mice ; Random Allocation ; Reproduction ; radiation effects ; Sperm Count ; Sperm Motility ; radiation effects ; Spermatozoa ; cytology ; metabolism ; radiation effects ; Testis ; cytology ; radiation effects

OBJECTIVETo investigate the relationship between microwave radiation and male reproductivity.

METHODSAfter filling out questionnaire and body check, we carried out molecular epidemiological studies, using single cell gel electrophoresis (SCGE) and sperm automatic analysis among people working on radar.

RESULTSQuality of semen and semi-clinical injury of sperm among the people working on radar had changed when radar electromagnetic wave frequency distance, intensity, lasting time and protection shield were changing. Dose-response relationship was noticed and the increase of sperm dysmorphia played a principal role. The results between exposed group and control group showed significant difference (P < 0.01).

CONCLUSIONPeople working on radar who suffered from non-ionization for long time and had bad radar shield protection would show semi-clinical injury on sperm and bad semen quality. However, it did not affect the male reproductive function. It was necessary to reinforce the protection of non-ionization and to improve male reproductive health care of people working on radar.

Adult ; Comet Assay ; Cross-Sectional Studies ; Dose-Response Relationship, Radiation ; Fertility ; physiology ; radiation effects ; Humans ; Male ; Occupational Exposure ; analysis ; Radar ; Radiation, Nonionizing ; Spermatozoa ; cytology ; radiation effects ; Time Factors

Animals ; Down-Regulation ; radiation effects ; Heavy Ion Radiotherapy ; adverse effects ; Infertility, Male ; etiology ; Male ; Mice ; Random Allocation ; Sperm Motility ; radiation effects ; Spermatozoa ; metabolism ; radiation effects ; Tubulin ; metabolism

OBJECTIVETo investigate the effect of simulated microgravity and carbon ion irradiation (CIR) on spermatogenic cell apoptosis and sperm DNA damage to the testis of male Swiss Webster mice, and assess the risk associated with space environment.

METHODSSperm DNA damage indicated by DNA fragmentation index (DFI) and high DNA stainability (HDS) was measured by sperm chromatin structure assay (SCSA). Apoptosis of spermatogenic cells was detected by annexin V-propidium iodide assay. Bax (the expression levels of p53) and proliferating cell nuclear antigen (PCNA) were measured by immunoblotting; p53 and PCNA were located by immunohistology.

RESULTSHDS, DFI, apoptosis index, and the expression levels of p53 and Bax were detected to be significantly higher in the experimental groups (P<0.05) compared with those in the control group; however, the PCNA expression varied to a certain degree. p53- and PCNA- positive expression were detected in each group, mainly in relation to the spermatogonic cells and spermatocytes.

CONCLUSIONThe findings of the present study demonstrated that simulated microgravity and CIR can induce spermatogenic cell apoptosis and sperm DNA damage. Sperm DNA damage may be one of the underlying mechanisms behind male fertility decline under space environment. These findings may provide a scientific basis for protecting astronauts and space traveler's health and safety.

Animals ; Apoptosis ; radiation effects ; Carbon ; Cell Proliferation ; radiation effects ; DNA Damage ; Heavy Ions ; adverse effects ; Immunohistochemistry ; Male ; Mice ; Random Allocation ; Sperm Count ; Spermatogenesis ; radiation effects ; Spermatozoa ; radiation effects ; Testis ; radiation effects ; Weightlessness Simulation

OBJECTIVETo study the effects of 50 Hz electromagnetic fields (EMFs) on DNA of testicular cells and sperm chromatin structure in mice.

METHODSMice were exposed to 50 Hz, 0.2 mT or 6.4 mT electromagnetic fields for 4 weeks. DNA strand breakage in testicular cells was detected by single-cell gel electrophoresis assay. Sperm chromatin structure was analyzed by sperm chromatin structure assay with flow cytometry.

RESULTSAfter 50 Hz, 0.2 mT or 6.4 mT EMFs exposure, the percentage of cells with DNA migration in total testicular cells increased from the control level of 25.64% to 37.83% and 39.38% respectively. The relative length of comet tail and the percentage of DNA in comet tail respectively increased from the control levels of 13.06% +/- 12.38% and 1.52% +/- 3.25% to 17.86% +/- 14.60% and 2.32% +/- 4.26% after 0.2 mT exposure and to 17.88% +/- 13.71% and 2.35% +/- 3.87% after 6.4 mT exposure (P < 0.05). Exposure to EMFs had not induced significant changes in S.D.alphaT and XalphaT, but COMPalphaT (cells outside the main population of alpha t), the percentage of sperms with abnormal chromatin structure, increased in the two exposed groups.

CONCLUSION50 Hz EMFs may have the potential to induce DNA strand breakage in testicular cells and sperm chromatin condensation in mice.

Animals ; Chromatin ; radiation effects ; ultrastructure ; Comet Assay ; DNA ; analysis ; radiation effects ; DNA Damage ; Electromagnetic Fields ; Flow Cytometry ; Male ; Mice ; Mice, Inbred Strains ; Spermatozoa ; radiation effects ; ultrastructure ; Testis ; cytology ; radiation effects

OBJECTIVETo determine whether laser-assisted immobilization of sperm damages sperm DNA.

METHODSTwenty-three semen samples were selected from an IVF program. Then normal spermatozoa were obtained by swimming-up method and immobilized with the tail by 0.45 ms pulse laser. Terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL) and single cell gel electrophoresis (SCGE) were used to detect sperm DNA damage.

RESULTSThere was no significant difference either before and after laser treatment in the percentage of TUNEL-positive spermatozoa ([1.32 +/- 0.61]% vs [1.41 +/- 0.51]%, P > 0.05) or in SCGE ([1.59 +/- 0.70]% vs [1.83 +/- 0.68]%, P > 0.05).

CONCLUSIONLaser-assisted sperm immobilization may cause no direct damage to the sperm DNA.

Comet Assay ; DNA Damage ; radiation effects ; Humans ; In Situ Nick-End Labeling ; In Vitro Techniques ; Lasers ; Male ; Semen ; radiation effects ; Sperm Motility ; Spermatozoa