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1.
J Photochem Photobiol B ; 216: 112112, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33524930

RESUMEN

For the first time, using sturgeon sperm as a model system, sensitive to optical radiation, the comparative studies of biological effect of continuous wave, quasi-continuous wave, nano- and picosecond laser radiation under conditions with equal average irradiance (3 mW/cm2) and wavelength (532 nm) have been carried out. Analyzing the parameters of spermatozoa motion it has been shown that, depending on the energy dose and mode of laser operation, the radiation may have both stimulatory and inhibitory effect on the velocity of motion and spermatozoa motility duration as well as on sustaining of functional characteristics of cold-stored sperm. The possibility of increasing the fertilization rate due to use of the sperm preliminary treated with laser radiation is demonstrated. For the first time, the possibility of enhancement of biological effect going from continuous wave to quasi-continuous wave laser radiation at equal irradiance and wavelength has experimentally been proven. It is shown that the difference in biological effect of continuous wave, quasi-continuous wave, nano- and picosecond laser radiation is due to amplitude (peak) values of intensity. Using fluorescence analysis and luminol-dependent chemiluminescence assay, evidence for the participation of endogenous flavins and metal-free porphyrins in sensitized ROS formation (singlet oxygen, hydrogen peroxide, and hydroxyl radicals) in sturgeon sperm was obtained. Mechanisms of photochemical and photothermal reactions explaining the difference in efficacy of action of laser radiation in above modes are discussed.


Asunto(s)
Fertilización/efectos de la radiación , Fármacos Fotosensibilizantes/química , Espermatozoides/efectos de la radiación , Animales , Cordados , Relación Dosis-Respuesta en la Radiación , Flavinas/química , Flavinas/metabolismo , Peróxido de Hidrógeno/química , Peróxido de Hidrógeno/metabolismo , Radical Hidroxilo/química , Radical Hidroxilo/metabolismo , Rayos Láser , Mediciones Luminiscentes , Masculino , Procesos Fotoquímicos , Porfirinas/química , Porfirinas/metabolismo , Especies Reactivas de Oxígeno/química , Especies Reactivas de Oxígeno/metabolismo , Motilidad Espermática/efectos de la radiación , Nanomedicina Teranóstica
2.
J Obstet Gynaecol Res ; 46(1): 124-132, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31646731

RESUMEN

AIM: To report the reproductive results and symptomatic relief of patients with adenomyosis who attempted to conceive after ultrasound-guided radiofrequency ablation (RFA). METHODS: Of 182 consecutive patients with adenomyosis who had undergone RFA, only 81 patients were eligible for this study. Pregnancy outcomes, postoperative complications, preoperative and postoperative pictorial blood loss assessment chart scores, and pain scores were evaluated. RESULTS: Of these 81 patients, 74 were infertile and seven were single at the time of RFA. The mean age at the time of operation was 35.8 years. The mean duration from the time of RFA to conception was 18.9 months (range, 2-72 months). Fifty-nine patients tried natural conception, while 22 patients attempted conception with assisted reproductive techniques. Twenty-nine (35.8%) patients achieved 39 pregnancies. Except for the 23 patients who did not actively try to conceive and who inevitably or arbitrarily discontinued pregnancy attempts, the pregnancy success rate reached 50%. Twenty-two (84.6%) of the 29 patients delivered 24 (66.7%) live babies (nine vaginal deliveries and 15 cesarean sections). Twelve (33.3%) pregnancies ended in spontaneous abortions. No uterine ruptures occurred. Paired sample t-tests revealed that preoperative pictorial blood loss assessment chart and pain scores were significantly (P < 0.05) different from the postoperative scores at 1-, 3- and 6-months. CONCLUSION: RFA could be considered a minimally-invasive treatment option for patients with adenomyosis who desire to maintain fertility and alleviate symptoms.


Asunto(s)
Adenomiosis/radioterapia , Ultrasonido Enfocado de Alta Intensidad de Ablación/efectos adversos , Infertilidad Femenina/fisiopatología , Traumatismos por Radiación/fisiopatología , Ablación por Radiofrecuencia/efectos adversos , Adulto , Femenino , Preservación de la Fertilidad/métodos , Fertilización/efectos de la radiación , Ultrasonido Enfocado de Alta Intensidad de Ablación/métodos , Humanos , Infertilidad Femenina/etiología , Embarazo , Resultado del Embarazo , Índice de Embarazo , Traumatismos por Radiación/etiología , Ablación por Radiofrecuencia/métodos , Resultado del Tratamiento , Vagina
3.
J Plant Res ; 130(3): 443-453, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28271338

RESUMEN

Brown algae exhibit three patterns of sexual reproduction: isogamy, anisogamy, and oogamy. Unicellular swarmers including gametes and zoospores bear two heterogenous flagella, an anterior flagellum with mastigonemes (fine tripartite hairs) and a posterior one. In seawater, these flagellates usually receive physico-chemical signals for finding partners and good habitats. It is well known that brown algal swarmers change their swimming direction depending on blue light (phototaxis), and male gametes do so, based on the sex pheromones from female gametes (chemotaxis). In recent years, the comparative analysis of chemotaxis in isogamy, anisogamy, and oogamy has been conducted. In this paper, we focused on the phototaxis and chemotaxis of brown algal gametes comparing the current knowledge with our recent studies.


Asunto(s)
Quimiotaxis/fisiología , Fertilización/fisiología , Phaeophyceae/fisiología , Fototaxis/fisiología , Fertilización/efectos de la radiación , Flagelos/fisiología , Flagelos/efectos de la radiación , Fluorescencia , Luz , Phaeophyceae/clasificación , Phaeophyceae/citología , Phaeophyceae/efectos de la radiación , Feromonas/química , Feromonas/fisiología , Reproducción/fisiología , Reproducción/efectos de la radiación , Motilidad Espermática/fisiología
4.
Photomed Laser Surg ; 35(3): 127-135, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28056208

RESUMEN

OBJECTIVE: The aim of this study was to investigate the photobiomodulation (PBM) effect of the 808 nm diode laser irradiation on spermatozoa, eggs, fertilized eggs, embryos, and larvae of Paracentrotus lividus, using two different power settings. BACKGROUND DATA: Studies have shown the possible use of PBM in artificial insemination. These have shown the potential effect of low-power laser irradiation on spermatozoa, while there are few studies on the effect of laser photonic energy on oocytes and almost no reports on the influence of lasers in embryogenesis. METHODS: P. lividus gametes, zygotes, embryos, and larvae were irradiated using the 808 nm diode laser (fluence 64 J/cm2 using 1 W or 192 J/cm2 with 3 W) with a flat-top hand-piece delivery, compared to a control without laser irradiation (0 J/cm2-0 W). The fertilization rate and the early developmental stages were investigated. RESULTS: The fertilization ability was not affected by the sperm/egg irradiation. At the gastrula stage, no significant differences were observed compared with the control samples. In the late pluteus stage, there were no differences in the developmental percentage observed between the control and the treated samples (1 W), with the exception of larvae from gastrulae and larvae, which were irradiated at 3 W. CONCLUSIONS: This study has demonstrated that both the 64 J/cm2-1 W and the 192 J/cm2-3 W do not induce morphological damage on the irradiated P. lividus gametes whose zygotes generate normal embryos and larvae. Our data therefore support the assumption to use higher fluence in preliminary studies on in vitro fertilization.


Asunto(s)
Erizos de Mar/efectos de la radiación , Espermatozoides/efectos de la radiación , Tocoferoles , Animales , Desarrollo Embrionario/efectos de la radiación , Fertilización/efectos de la radiación , Larva , Masculino , Erizos de Mar/fisiología
5.
Sci Rep ; 6: 19812, 2016 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-26804186

RESUMEN

Pollen tubes are polarly growing plant cells that are able to rapidly respond to a combination of chemical, mechanical, and electrical cues. This behavioural feature allows them to invade the flower pistil and deliver the sperm cells in highly targeted manner to receptive ovules in order to accomplish fertilization. How signals are perceived and processed in the pollen tube is still poorly understood. Evidence for electrical guidance in particular is vague and highly contradictory. To generate reproducible experimental conditions for the investigation of the effect of electric fields on pollen tube growth we developed an Electrical Lab-on-Chip (ELoC). Pollen from the species Camellia displayed differential sensitivity to electric fields depending on whether the entire cell or only its growing tip was exposed. The response to DC fields was dramatically higher than that to AC fields of the same strength. However, AC fields were found to restore and even promote pollen growth. Surprisingly, the pollen tube response correlated with the conductivity of the growth medium under different AC frequencies--consistent with the notion that the effect of the field on pollen tube growth may be mediated via its effect on the motion of ions.


Asunto(s)
Camellia/crecimiento & desarrollo , Electricidad , Dispositivos Laboratorio en un Chip , Tubo Polínico/crecimiento & desarrollo , Camellia/efectos de la radiación , Conductividad Eléctrica , Fertilización/efectos de la radiación , Flores/crecimiento & desarrollo , Flores/efectos de la radiación , Polen/crecimiento & desarrollo , Polen/efectos de la radiación , Tubo Polínico/genética , Tubo Polínico/efectos de la radiación
6.
Elife ; 42015 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-25601414

RESUMEN

Optogenetics is a powerful technique to control cellular activity by light. The light-gated Channelrhodopsin has been widely used to study and manipulate neuronal activity in vivo, whereas optogenetic control of second messengers in vivo has not been examined in depth. In this study, we present a transgenic mouse model expressing a photoactivated adenylyl cyclase (bPAC) in sperm. In transgenic sperm, bPAC mimics the action of the endogenous soluble adenylyl cyclase (SACY) that is required for motility and fertilization: light-stimulation rapidly elevates cAMP, accelerates the flagellar beat, and, thereby, changes swimming behavior of sperm. Furthermore, bPAC replaces endogenous adenylyl cyclase activity. In mutant sperm lacking the bicarbonate-stimulated SACY activity, bPAC restored motility after light-stimulation and, thereby, enabled sperm to fertilize oocytes in vitro. We show that optogenetic control of cAMP in vivo allows to non-invasively study cAMP signaling, to control behaviors of single cells, and to restore a fundamental biological process such as fertilization.


Asunto(s)
Fertilización , Optogenética/métodos , Transducción de Señal , Espermatozoides/metabolismo , Adenilil Ciclasas/metabolismo , Animales , Calcio/metabolismo , AMP Cíclico , Fertilidad/efectos de la radiación , Fertilización/efectos de la radiación , Espacio Intracelular/metabolismo , Masculino , Ratones , Ratones Transgénicos , Protaminas/genética , Transducción de Señal/efectos de la radiación , Solubilidad , Motilidad Espermática/efectos de la radiación , Espermatozoides/efectos de la radiación , Rayos Ultravioleta
7.
J Comp Physiol B ; 185(1): 47-55, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25240789

RESUMEN

Parental transcript legacy plays an important role in fertilization and development of the early embryo. Parental environmental exposure affects the fertilization of eggs, but the underlying biochemical mechanism is largely unresolved. In this study, the parental environmental effects on fertilization of eggs were explored in the silkworm Bombyx mori (B. mori), an ideal lepidopteran animal model. The results showed that the rate of fertilization decreased after the parents were exposed to a poor environment at 32 °C with continuous illumination for 72 h on days 6-9 of the pupal stage, which is a key period for germ cell maturation. This was likely attributable to lower energy charge values, obstructed nicotinamide adenine dinucleotide (NAD(+)) regeneration and inactive tricarboxylic acid cycle (TCA), leading to accumulation of large amounts of pyruvic acid and lactic acid. This effect was related to energy metabolism via glycolysis; in particular disruption of pyruvate metabolism. In conclusion, this study showed parental exposure to an abnormal environment during germ cell maturation affected glycolysis and the subsequent fertilization of eggs via the parental transcript legacy in B. mori.


Asunto(s)
Exposición a Riesgos Ambientales , Fertilización/efectos de la radiación , Células Germinativas/fisiología , Luz/efectos adversos , Animales , Bombyx , Ciclo del Ácido Cítrico/efectos de la radiación , Fertilización/fisiología , Glucólisis/efectos de la radiación , Ácido Láctico/metabolismo , NAD/metabolismo , Ácido Pirúvico/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa
8.
Theriogenology ; 80(2): 125-30, 2013 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-23602217

RESUMEN

Diploid androgenotes were produced without egg irradiation in the loach, Misgurnus anguillicaudatus. Eggs of wild-type diploid females were fertilized with diploid sperm of a neo-tetraploid male and then cold-shock treated at 3 °C (range, ±0.5 °C) for 30 minutes just after fertilization to eliminate the female nucleus. After hatching, ploidy status of the hatched larvae was analyzed by flow cytometry, which revealed putative diploid androgenotes as well as larvae possessing other ploidies. Five independent microsatellite DNA markers were genotyped to confirm all-male inheritance of the resultant diploid larvae. The mean ± SD yield rate of diploid androgenetic larvae to total eggs used was 12.29 ± 3.25% in the cold-shock group and 22.23 ± 13.42% in the UV-irradiated group (P > 0.05). No diploid androgenetic larvae were detected in the intact control group. To our knowledge, this is the first report demonstrating successful induction of diploid androgenotes without egg irradiation in fish.


Asunto(s)
Cipriniformes/fisiología , Diploidia , Procesos de Determinación del Sexo , Preselección del Sexo/veterinaria , Espermatozoides/fisiología , Cigoto/fisiología , Animales , Frío , Femenino , Fertilización/fisiología , Fertilización/efectos de la radiación , Genotipo , Masculino , Procesos de Determinación del Sexo/efectos de la radiación , Preselección del Sexo/métodos , Espermatozoides/efectos de la radiación , Tetraploidía , Rayos Ultravioleta , Cigoto/efectos de la radiación
9.
Am J Bot ; 99(10): 1702-14, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22984095

RESUMEN

PREMISE OF THE STUDY: Consequences of global climate change are detectable in the historically nitrogen- and phosphorus-limited Arctic tundra landscape and have implications for the terrestrial carbon cycle. Warmer temperatures and elevated soil nutrient availability associated with increased microbial activity may influence rates of photosynthesis and respiration. • METHODS: This study examined leaf-level gas exchange, cellular ultrastructure, and related leaf traits in two dominant tundra species, Betula nana, a woody shrub, and Eriophorum vaginatum, a tussock sedge, under a 3-yr-old treatment gradient of nitrogen (N) and phosphorus (P) fertilization in the North Slope of Alaska. • KEY RESULTS: Respiration increased with N and P addition-the highest rates corresponding to the highest concentrations of leaf N in both species. The inhibition of respiration by light ("Kok effect") significantly reduced respiration rates in both species (P < 0.001), ranged from 12-63% (mean 34%), and generally decreased with fertilization for both species. However, in both species, observed rates of photosynthesis did not increase, and photosynthetic nitrogen use efficiency generally decreased under increasing fertilization. Chloroplast and mitochondrial size and density were highly sensitive to N and P fertilization (P < 0.001), though species interactions indicated divergent cellular organizational strategies. • CONCLUSIONS: Results from this study demonstrate a species-specific decoupling of respiration and photosynthesis under N and P fertilization, implying an alteration of the carbon balance of the tundra ecosystem under future conditions.


Asunto(s)
Betula/metabolismo , Ciclo del Carbono , Cyperaceae/metabolismo , Nitrógeno/metabolismo , Fósforo/metabolismo , Hojas de la Planta/citología , Hojas de la Planta/metabolismo , Análisis de Varianza , Regiones Árticas , Betula/citología , Betula/crecimiento & desarrollo , Betula/ultraestructura , Biomasa , Ciclo del Carbono/efectos de la radiación , Dióxido de Carbono/metabolismo , Respiración de la Célula/efectos de la radiación , Cloroplastos/metabolismo , Cloroplastos/efectos de la radiación , Cloroplastos/ultraestructura , Cyperaceae/citología , Cyperaceae/crecimiento & desarrollo , Cyperaceae/ultraestructura , Fertilización/efectos de la radiación , Luz , Células del Mesófilo/citología , Células del Mesófilo/efectos de la radiación , Células del Mesófilo/ultraestructura , Mitocondrias/metabolismo , Mitocondrias/efectos de la radiación , Mitocondrias/ultraestructura , Consumo de Oxígeno/efectos de la radiación , Fotosíntesis/efectos de la radiación , Hojas de la Planta/anatomía & histología , Hojas de la Planta/efectos de la radiación , Estaciones del Año , Temperatura
10.
Drug Chem Toxicol ; 35(1): 36-42, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21848393

RESUMEN

Nonylphenol (NP) is an environmental chemical with estrogenic activity. Exposure of the general population to radiation and NP is, very often, unavoidable because of the presence of both agents in the environment of human life and work. The aim of the study was to investigate the effect of subchronic 8-week exposure to NP alone or in combination with X-rays on sperm quantity and quality and on the possibility of the transmission of mutations induced in germ cells to the next generation. Eight-week exposure to NP and X-ray/NP combination diminished sperm count and increased the percent of abnormal spermatozoa, as well as having increased DNA damage in gametes. Some of those effects remained up to 8 weeks after the end of exposure. The exposure of males to 50 mg/kg body weight (b.w.) of NP and to 0.05 Gy + 25 mg/kg b.w. NP daily significantly decreased the percent of pregnant females. The fertilization ability of male mice was not diminished. Combined exposure to low doses of both agents significantly increased the mean number of dead implantations per pregnant female and the percentage of skeletal malformations. Results showed that mutations induced in germ cells by subchronic exposure to NP and to combined X-ray/NP exposure may be transmitted to the F1 generation via sperm.


Asunto(s)
Contaminantes Ambientales/toxicidad , Fenoles/toxicidad , Rayos X/efectos adversos , Animales , Daño del ADN/efectos de los fármacos , Daño del ADN/efectos de la radiación , Femenino , Fertilización/efectos de los fármacos , Fertilización/efectos de la radiación , Células Germinativas/efectos de los fármacos , Células Germinativas/efectos de la radiación , Masculino , Ratones , Mutágenos/toxicidad , Embarazo , Recuento de Espermatozoides , Espermatozoides/efectos de los fármacos , Espermatozoides/efectos de la radiación
11.
Plant Cell Rep ; 30(6): 1099-106, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21305302

RESUMEN

Gynogenesis was investigated on gentian (Gentiana triflora, G. scabra and their hybrids), which is an important ornamental flower. When unfertilized ovules were cultured in 1/2 NLN medium containing a high concentration of sucrose (100 g/l), embryo-like structures (ELS) were induced. Although genotypic variation was observed in ELS induction, all four genotypes produced ELSs ranging from 0.93 to 0.04 ELSs per flower bud. The ovules collected from flower buds of later stages (just before anthesis or flower anthesis) tended to exhibit higher response. The dark culture condition produced more than four times as many ELSs than in 16-h light condition. A significant number of plantlets were directly regenerated from ELSs on MS regeneration medium. The ploidy levels of 179 regenerated plants were determined by flow cytometry, revealing that the majority of them were diploid (55.9%) and haploid (31.3%). When a total of 54 diploid plants were examined by molecular genetic markers, 52 (96.3%) were considered as doubled haploids (DHs). This is the first report showing successful gynogenesis in gentian. The production of haploids and DHs by unfertilized ovule culture opens a novel prospect in gentian F1 hybrid breeding.


Asunto(s)
Diploidia , Gametogénesis en la Planta/genética , Gentiana/genética , Haploidia , Técnicas de Cultivo de Tejidos/métodos , Fertilización/efectos de la radiación , Citometría de Flujo , Flores/genética , Flores/crecimiento & desarrollo , Flores/efectos de la radiación , Gametogénesis en la Planta/efectos de la radiación , Marcadores Genéticos , Genotipo , Gentiana/embriología , Gentiana/fisiología , Gentiana/efectos de la radiación , Homocigoto , Luz , Regeneración/fisiología , Regeneración/efectos de la radiación , Semillas/crecimiento & desarrollo , Semillas/efectos de la radiación
12.
Int J Androl ; 34(1): 20-6, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20236367

RESUMEN

Several recent studies have indicated that radiofrequency electromagnetic fields (RF-EMF) have an adverse effect on human sperm quality, which could translate into an effect on fertilization potential. This study evaluated the effect of RF-EMF on sperm-specific characteristics to assess the fertilizing competence of sperm. Highly motile human spermatozoa were exposed for 1 h to 900-MHz mobile phone radiation at a specific absorption rate of 2.0 W/kg and examined at various times after exposure. The acrosome reaction was evaluated using flow cytometry. The radiation did not affect sperm propensity for the acrosome reaction. Morphometric parameters were assessed using computer-assisted sperm analysis. Significant reduction in sperm head area (9.2 ± 0.7 µm² vs. 18.8 ± 1.4 µm²) and acrosome percentage of the head area (21.5 ± 4% vs. 35.5 ± 11.4%) was reported among exposed sperm compared with unexposed controls. Sperm-zona binding was assessed directly after exposure using the hemizona assay. The mean number of zona-bound sperm of the test hemizona and controls was 22.8 ± 12.4 and 31.8 ± 12.8 (p < 0.05), respectively. This study concludes that although RF-EMF exposure did not adversely affect the acrosome reaction, it had a significant effect on sperm morphometry. In addition, a significant decrease in sperm binding to the hemizona was observed. These results could indicate a significant effect of RF-EMF on sperm fertilization potential.


Asunto(s)
Reacción Acrosómica/efectos de la radiación , Teléfono Celular , Ondas de Radio/efectos adversos , Cabeza del Espermatozoide/efectos de la radiación , Espermatozoides/efectos de la radiación , Zona Pelúcida/efectos de la radiación , Acrosoma/efectos de la radiación , Adulto , Fármacos para la Fertilidad Masculina/efectos de la radiación , Fertilización/efectos de la radiación , Citometría de Flujo , Humanos , Masculino , Motilidad Espermática/efectos de la radiación , Interacciones Espermatozoide-Óvulo/efectos de la radiación
13.
Aquat Toxicol ; 97(1): 3-14, 2010 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-20047765

RESUMEN

This review summarizes current knowledge on ultraviolet radiation (UVR)-induced cellular and molecular damage in marine ectotherms (invertebrates and fish). UVR impairs sperm motility, reduces fertilization, and causes embryo malformation that in turn affects recruitment and therefore the sustainability of natural populations. The direct molecular effects of UVR are mediated by absorption of certain wavelengths by specific macromolecules and the dissipation of the absorbed energy via photochemical reactions. Most organisms have defense mechanisms that either prevent UVR-induced damage, or mechanisms that repair the damage. Photoprotective pigments, antioxidant defense compounds, and cell cycle development genes are some of the molecules involved in UVR defense. Photoenzymatic repair and nucleotide excision repair are the two primary DNA repair systems in marine ectotherms. We anticipate that toxicogenomic studies will gain importance in UVR research because they can elucidate the primary processes involved in UVR damage and the cellular response to this damage.


Asunto(s)
Peces/fisiología , Invertebrados/efectos de la radiación , Rayos Ultravioleta/efectos adversos , Animales , Daño del ADN/efectos de la radiación , Reparación del ADN , Ecotoxicología , Embrión no Mamífero/efectos de la radiación , Fertilización/efectos de la radiación , Peces/genética , Células Germinativas/efectos de la radiación , Invertebrados/genética , Biología Marina , Metagenómica , Motilidad Espermática/efectos de la radiación
14.
Mar Biotechnol (NY) ; 11(2): 243-51, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-18779997

RESUMEN

Half-smooth tongue sole (Cynoglossus semilaevis) is an important cultured marine fish as well as a promising model fish for the study of sex determination mechanisms. In the present study, a protocol for artificial gynogenesis of half-smooth tongue sole was developed in order to identify the sex determination mechanism and to generate all-female stock. The optimal UV-irradiation dose for genetically inactivating sea perch spermatozoa was determined to be > or =30 mJ/cm(2). The optimal initiation time for cold shock of gynogenetic embryos was determined to be 5 min after fertilization, while the optimal temperature and treatment duration were determined to be 20-25 min at 5 degrees C. Chromosomes from common diploids, gynogenetic haploids, and diploids were analyzed. WW chromosomes were discovered in some of the gynogenetic diploids. The microsatellite marker was applied to analyze gynogenetic diploid fry. Among the 30 gynogenetic diploid fry, 11 fry contained only one allele, while 19 contained two alleles, which had the same genotype as their mother. The female-specific DNA marker was observed in four individuals out of ten gynogenetic diploid fry. Ploidy analysis of 20 putative gynogenetic fry showed them all to be diploid. Thus, a protocol for the induction of artificial gynogenesis has been developed for the first time in half smooth tongue sole, and the sex determination mechanism in the tongue sole was determined to be female heterogametic with the ZW chromosome.


Asunto(s)
Peces Planos/fisiología , Procesos de Determinación del Sexo , Preselección del Sexo/veterinaria , Animales , Quimera/fisiología , Frío , Diploidia , Fertilización/efectos de la radiación , Peces Planos/genética , Haploidia , Percas/fisiología , Preselección del Sexo/métodos , Análisis de Supervivencia , Factores de Tiempo , Rayos Ultravioleta
15.
J Med Entomol ; 45(4): 698-705, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18714870

RESUMEN

Male mating competitiveness is a crucial parameter in many genetic control programs including the sterile insect technique (SIT). We evaluated competitiveness of male Anopheles arabiensis Patton as a function of three experimental variables: (1) small or large cages for mating, (2) the effects of either a partially sterilizing (70 Gy) or fully sterilizing (120 Gy) dose, and (3) pupal or adult irradiation. Irradiated males competed for females with an equal number of unirradiated males. Competitiveness was determined by measuring hatch rates of individually laid egg batches. In small cages, pupal irradiation with the high dose resulted in the lowest competitiveness, whereas adult irradiation with the low dose gave the highest, with the latter males being equal in competitiveness to unirradiated males. In the large cage, reduced competitiveness of males irradiated in the pupal stage was more pronounced compared with the small cage; the males irradiated as adults at both doses performed similarly to unirradiated males. Unexpectedly, males irradiated with the high dose performed better in a large cage than in a small one. A high proportion of intermediate hatch rates was observed for eggs collected in the large cage experiments with males irradiated at the pupal stage. It is concluded that irradiation of adult An. arabiensis with the partially sterilizing dose results in the highest competitiveness for both cage designs. Cage size affected competitiveness for some treatments; therefore, competitiveness determined in laboratory experiments must be confirmed by releases into simulated field conditions. The protocols described are readily transferable to evaluate male competitiveness for other genetic control techniques.


Asunto(s)
Anopheles/fisiología , Conducta Competitiva/fisiología , Conducta Competitiva/efectos de la radiación , Fertilización/efectos de la radiación , Infertilidad Masculina/etiología , Óvulo/fisiología , Conducta Sexual Animal/fisiología , Conducta Sexual Animal/efectos de la radiación , Animales , Embrión no Mamífero/efectos de los fármacos , Embrión no Mamífero/fisiología , Vivienda para Animales , Laboratorios , Masculino , Pupa
16.
Hum Fertil (Camb) ; 9(4): 223-9, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17190668

RESUMEN

The effect of seasonality and daylight length on mammalian reproduction leading to spring births has been well established, and is known as photoperiodism. In assisted reproduction there is much greater uncertainty as to the effect of seasonality. This was a 4-year retrospective analysis of 2709 standardised cycles of IVF/ICSI. Data was analysed with regard to the 1642 cycles occurring during the months of extended daylight (Apr-Sept) and those 1067 cycles during winter months of restricted light length (Oct-Mar). The results showed that there was significant improvement in assisted conception outcomes in cycles performed in summer (lighter) months with more efficient ovarian stimulation 766iu v880iu/per oocyte retrieved (p=0.006). There was similarly a significantly improved implantation rate per embryo transferred 11.42% vs 9.35% (p=0.011) and greater clinical pregnancy rate 20% vs 15% (p=0.0033) during summer cycles. This study appears to demonstrate a significant benefit of increased daylight length on outcomes of IVF/ICSI cycles. Whilst the exact mechanism of this is unclear, it would seem probable that melatonin may have actions at multiple sites and on multiple levels of the reproductive tract, and may exert a more profound effect on outcomes of assisted conception cycles than has been previously considered.


Asunto(s)
Fertilización In Vitro , Fertilización/fisiología , Fertilización/efectos de la radiación , Fotoperiodo , Estaciones del Año , Adulto , Femenino , Humanos , Resultado del Tratamiento
17.
Electromagn Biol Med ; 25(2): 87-96, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16771297

RESUMEN

Eggs from a layer-type breeder flock (Baladi, King Saud University) between 61 and 63 weeks of age were used in 3 trials to study the effects of electric field (EF) during incubation on the internal temperature of incubation, and eggs and hemoglobin (Hb) dielectric of chicken embryos at 18 days of age. Dielectric relative permittivity (epsilon') and conductivity (sigma) of Hb were examined in the range of frequency from 20 to 100 kHz. The values of dielectric increment (Deltaepsilon') and the relaxation times (tau) of Hb molecules were calculated. The internal temperature of eggs was measured in empty (following the removal of egg contents) and fertilized eggs in trials 1 and 2, respectively. The level of the EF was 30 kV/m, 60 Hz. EF incubation of embryos influenced the temperature of incubation and electrical properties of Hb molecules and did not influence the temperature of incubation and internal environment of eggs when empty eggs were incubated. EF incubation of fertilized eggs significantly raised the temperature of incubation, egg air cell, and at the surface of the egg yolk by approximately 0.09, 0.60, and 0.61 degrees F, respectively and Hb epsilon', sigma, Deltaepsilon', and tau as a function of the range of frequency of 20 to 100 kHz when compared with their counterparts of the control group. It was concluded that the exposure of fertilized chicken eggs to EF of 30 kV/m, 60 Hz, during incubation altered dielectric properties of Hb and that probably affected cell to cell communication and created the right environment for enhancing the growing process and heat production of embryos consequently increasing the temperature of the internal environment of the egg, and incubation.


Asunto(s)
Cáscara de Huevo/efectos de la radiación , Yema de Huevo/efectos de la radiación , Campos Electromagnéticos , Desarrollo Embrionario/efectos de la radiación , Fertilización/efectos de la radiación , Hemoglobinas , Animales , Embrión de Pollo , Cáscara de Huevo/fisiología , Yema de Huevo/fisiología , Desarrollo Embrionario/fisiología , Temperatura , Factores de Tiempo
18.
Theriogenology ; 64(8): 1809-22, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15921734

RESUMEN

Preservation of DNA integrity is essential for protection of sperm quality. This study examined, with the use of comet assay, DNA fragmentation of rainbow trout (Oncorhynchus mykiss) spermatozoa subjected to UV irradiation (2,075 microW/cm(2), 0-15 min) or oxidative stress induced by hydrogen peroxide (0-20mM). Sperm motility and fertilizing ability were also measured. A dramatic increase in DNA fragmentation was recorded after 5 min UV irradiation but no significant changes in sperm motility were observed at this time. Longer irradiation resulted in a decrease in motility parameters and further increase of DNA fragmentation. UV irradiation caused a clear decrease in the percentage of eyed embryos and most of the embryos did not hatch. When highly diluted sperm suspensions (50,000-fold) were exposed to 0.1mM H(2)O(2) evident increase in DNA fragmentation was observed. On the other hand, when more concentrated sperm suspensions (diluted only 40-fold) were employed (in order to conduct motility and fertilization measurements at the same time) 1-20mM H(2)O(2) caused only moderate increase in DNA fragmentation and dose-dependent decline in sperm motility and fertilizing ability. This suggests that toxic effects of H(2)O(2) were primarily related to inhibition of sperm motility. Our results demonstrate that comet assay can be used for monitoring the effectiveness of fish sperm DNA inactivation by UV irradiation. Therefore, the comet assay together with sperm motility analysis can be applied in optimization works of gynogenetic procedures in fish. Lack of effectiveness of H(2)O(2) in inducing major DNA fragmentation suggests presence of mechanisms of antioxidative defense in rainbow trout spermatozoa.


Asunto(s)
Fragmentación del ADN , Fertilización , Peróxido de Hidrógeno/farmacología , Oncorhynchus mykiss , Motilidad Espermática , Rayos Ultravioleta , Animales , Ensayo Cometa , Fragmentación del ADN/efectos de los fármacos , Fragmentación del ADN/efectos de la radiación , Fertilización/efectos de los fármacos , Fertilización/efectos de la radiación , Masculino , Motilidad Espermática/efectos de los fármacos , Motilidad Espermática/efectos de la radiación
19.
Radiol Technol ; 75(6): 419-24, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15352555

RESUMEN

The teratogenic effects of ionizing radiation are well documented, but less is known about the radiosensitivity of the human oocyte. Women of childbearing age are understandably concerned about diagnostic radiology examinations--their risk/benefit ratio and their impact on the ability to conceive. Current research and evidence gathered from studies of the long-term effects of intra-abdominal therapeutic radiation shed light on this subject. With respect to this issue, radiographers can now give more practical advice to their nongravid female patients.


Asunto(s)
Oocitos/efectos de la radiación , Tolerancia a Radiación , Aberraciones Cromosómicas/efectos de la radiación , Daño del ADN , Femenino , Fertilización/efectos de la radiación , Humanos , Fase Luteínica/efectos de la radiación , Meiosis/efectos de la radiación , Menopausia Prematura/efectos de la radiación , Ovulación/efectos de la radiación , Dosis de Radiación , Protección Radiológica , Radiografía/efectos adversos , Radioterapia/efectos adversos , Medición de Riesgo
20.
Br Poult Sci ; 44(4): 643-50, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-14584856

RESUMEN

1. The aim of the study was to investigate the possibility of preparing adult fowl testes for the production of exogenous germ-lines by eradication of recipient spermatogenesis using gamma-radiation. 2. A comparison between several radiation therapy treatments (based on 60Co isotope) of male testes was conducted using gamma-rays of 18, 22 and 26 Gy in a single dose or repeated doses of 5 x 8 Gy over a 15-d period. Sperm concentration and motility were determined after each treatment. 3. Altered spermatogenesis was observed after a single treatment dose of 18 Gy, while single doses of 26 Gy were followed by reduced sperm numbers (from 22 x 10(9) to 31 x 10(6) sperm/ml) within 60 to 100 d after treatment. After a single treatment of 26 Gy sperm motility was reduced by 50%. In contrast, a fractionated treatment (5 x 8 Gy) with gamma-rays halted spermatogenesis 39 d after the distribution of the first 8 Gy dose. 4. Observations of the seminiferous tubules by electron microscopy performed 12 months after this treatment confirmed that moderate doses of gamma-rays (8 Gy) distributed repeatedly (5 x) over a limited period (15 d) sterilise adult fowl testes but maintain morphologically normal somatic (Leydig and Sertoli) cell populations.


Asunto(s)
Quimera/fisiología , Rayos gamma , Espermatozoides/fisiología , Espermatozoides/efectos de la radiación , Testículo/fisiología , Animales , Membrana Celular/efectos de la radiación , Membrana Celular/ultraestructura , Pollos , Radioisótopos de Cobalto , Femenino , Fertilización/efectos de la radiación , Masculino , Análisis de Regresión , Recuento de Espermatozoides , Testículo/efectos de la radiación , Testículo/ultraestructura , Factores de Tiempo
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