[Cytomixis and its role in the regulation of plant fertility]

UV and gamma irradiation of barley seedlings induces an increase in the number of various pathologies in the male reproductive system of plants. The majority of cytological abnormalities are rather nonspecific. The main type of the observed pathologies of microsporogenesis is cytomixis, whose activation correlates with a callose hypersecretion in microsporocyte walls. A negative correlation between cytomixis and the sterility of microspores (in the case of gamma irradiation) or the sterility of mature pollen grains (in the case of UV-B irradiation) is revealed. It is supposed that cytomixis represents a kind of a premeiotic cell selection in plants characterized by an intraorganismic genetic heterogeneity (mosaics). The novelty of the idea is that the cytopathology that accompanies cytomixis is considered as a mechanism of the induced death of genetically imbalanced or nonrepairable cells, which is intended to keep the fertility of a male reproductive system. The activation of this mechanism has a threshold character.

Fertility preservation for patients with cancer: American Society of Clinical Oncology clinical practice guideline update

PURPOSE

To update guidance for health care providers about fertility preservation for adults and children with cancer.

METHODS

A systematic review of the literature published from March 2006 through January 2013 was completed using MEDLINE and the Cochrane Collaboration Library. An Update Panel reviewed the evidence and updated the recommendation language.

RESULTS

There were 222 new publications that met inclusion criteria. A majority were observational studies, cohort studies, and case series or reports, with few randomized clinical trials. After review of the new evidence, the Update Panel concluded that no major, substantive revisions to the 2006 American Society of Clinical Oncology recommendations were warranted, but clarifications were added.

RECOMMENDATIONS

As part of education and informed consent before cancer therapy, health care providers (including medical oncologists, radiation oncologists, gynecologic oncologists, urologists, hematologists, pediatric oncologists, and surgeons) should address the possibility of infertility with patients treated during their reproductive years (or with parents or guardians of children) and be prepared to discuss fertility preservation options and/or to refer all potential patients to appropriate reproductive specialists. Although patients may be focused initially on their cancer diagnosis, the Update Panel encourages providers to advise patients regarding potential threats to fertility as early as possible in the treatment process so as to allow for the widest array of options for fertility preservation. The discussion should be documented. Sperm and embryo cryopreservation as well as oocyte cryopreservation are considered standard practice and are widely available. Other fertility preservation methods should be considered investigational and should be performed by providers with the necessary expertise.

Remating behavior in Anastrepha fraterculus (Diptera: Tephritidae) females is affected by male juvenile hormone analog treatment but not by male sterilization

The sterile insect technique (SIT) has been proposed as an area-wide method to control the South American fruit fly, Anastrepha fraterculus (Wiedemann). This technique requires sterilization, a procedure that affects, along with other factors, the ability of males to modulate female sexual receptivity after copulation. Numerous pre-release treatments have been proposed to counteract the detrimental effects of irradiation, rearing and handling and increase SIT effectiveness. These include treating newly emerged males with a juvenile hormone mimic (methoprene) or supplying protein to the male's diet to accelerate sexual maturation prior to release. Here, we examine how male irradiation, methoprene treatment and protein intake affect remating behavior and the amount of sperm stored in inseminated females. In field cage experiments, we found that irradiated laboratory males were equally able to modulate female remating behavior as fertile wild males. However, females mated with 6-day-old, methoprene-treated males remated more and sooner than females mated with naturally matured males, either sterile or wild. Protein intake by males was not sufficient to overcome reduced ability of methoprene-treated males to induce refractory periods in females as lengthy as those induced by wild and naturally matured males. The amount of sperm stored by females was not affected by male irradiation, methoprene treatment or protein intake. This finding revealed that factors in addition to sperm volume intervene in regulating female receptivity after copulation. Implications for SIT are discussed.

Impacts of adelphophagic development on variation in offspring size, duration of development, and temperature-mediated plasticity

Adelphophagic development, where embryos consume sibling embryos or nurse eggs, is particularly common in marine caenogastropods and some families of polychaetes. When exogenous nutrition is provided before hatching, egg size and hatching size can be uncoupled, but advantages and constraints of adelphophagic development compared to development from large eggs are unknown. Here we examine temperature-mediated plasticity in offspring size, brooding duration, and fecundity in the adelphophagic marine gastropod Crepidula cf. onyx. We use these data combined with previously published data on two planktotrophic Crepidula and two Crepidula species that develop from large eggs to test hypotheses about the consequences of adelphophagic development and patterns of variation in offspring size. In Crepidula cf. onyx, egg size shows no significant effect of temperature. Hatching size is significantly larger at 28 °C than at 23 °C but proceeds from fewer eggs per capsule at 28 °C. Hatching size is therefore decoupled from both egg size and the number of eggs per capsule. Although development is faster at the higher temperature, broods are produced roughly every 26-27 days at both temperatures. Increased rate of development has been cited as a potential advantage of adelphophagic development in muricids, but the adelphophagic C. cf. onyx did not develop more quickly than C. atrasolea or C. ustulatulina, species that produce similarly sized hatchlings from large eggs. Comparisons across calyptraeid species support the role of adelphophagy in increasing variance in offspring size. This increased variability is primarily expressed within broods or among broods from the same female, not among females.

The sterile insect technique for controlling populations of Aedes albopictus (Diptera: Culicidae) on Reunion Island: mating vigour of sterilized males

Reunion Island suffers from high densities of the chikungunya and dengue vector Aedes albopictus. The sterile insect technique (SIT) offers a promising strategy for mosquito-borne diseases prevention and control. For such a strategy to be effective, sterile males need to be competitive enough to fulfil their intended function by reducing wild mosquito populations in natura. We studied the effect of irradiation on sexual maturation and mating success of males, and compared the sexual competitiveness of sterile versus wild males in the presence of wild females in semi-field conditions. For all untreated or sterile males, sexual maturation was completed within 13 to 20 h post-emergence and some males were able to inseminate females when 15 h old. In the absence of competition, untreated and sterile males were able to inseminate the same number of virgin females during 48 h, in small laboratory cages: an average of 93% of females was inseminated no matter the treatment, the age of males, and the sex ratio. Daily mating success of single sterile males followed the same pattern as for untreated ones, although they inseminated significantly fewer females after the ninth day. The competitiveness index of sterile males in semi-field conditions was only 0.14 when they were released at 1-day old, but improved to 0.53 when the release occurred after a 5-day period in laboratory conditions. In SIT simulation experiments, a 5∶1 sterile to wild male ratio allowed a two-fold reduction of the wild population’s fertility. This suggests that sterile males could be sufficiently competitive to mate with wild females within the framework of an SIT component as part of an AW-IPM programme for suppressing a wild population of Ae. albopictus in Reunion Island. It will be of interest to minimise the pre-release period in controlled conditions to ensure a good competitiveness without increasing mass rearing costs.

Normal tissue complications from low-dose proton therapy

Proton therapy is an attractive method to attenuate toxicities of radiotherapy because of the decrease of integral radiation dose to normal tissues, which should lead to fewer late side effects. This potential benefit is of particular interest in the pediatric population, since children are more vulnerable to the risks of radiation. In addition, overall survival rates for pediatric malignancies continue to improve, which will lead to more long-term survivors who will be at risk from the late effects of radiation therapy that was used for treatment. In this review, the potential benefits afforded by proton therapy in the low-dose area for radiosensitive organs will be evaluated. Because robust clinical information is not available for low-dose proton therapy, information from the experience of photon therapy in radiosensitive structures will be reviewed. In general, because the low-dose bath is reduced or on occasion eliminated with the use of proton therapy, a reduction of early and late toxicities related to low-dose radiotherapy such as vomiting, mucositis, cardiovascular complications, pulmonary injury, and developmental effects in children is expected. Other authors review the current evidence and potential benefits supporting the use of proton therapy for the reduction in neuro-cognitive sequelae and secondary malignancies. Currently, a relative biological effectiveness of 1.1 is used in clinical situations to calculate the equivalent biologic dose for proton therapy relative to photon therapy. The unit of dose is commonly referred to as gray equivalent (GyEq). The interaction of a proton at a cellular level is postulated to lead to a higher frequency of double-strand breaks, so in theory there is a higher probability of cell kill and a lower probability of mutagenesis. At this time, however, once the physical properties of the interaction of proton with matter are accounted for, there is no definite data that 1 GyEq has any different biologic outcome than 1 Gy delivered with photon therapy. In the Bragg peak, there is greater uncertainty of dose deposition and associated biologic effect. In clinical practice, therefore, one avoids placing the Bragg peak on critical structures such as the brainstem, spinal cord, or optic chiasm. In summary, it appears that normal tissue tolerance of proton radiotherapy is likely to be similar to photon radiation for equivalent biologic doses. Overall, it is anticipated that there will be a lower risk of normal tissue toxicity associated with proton therapy because of a lower delivered dose outside of the target tissue.

Effects of parental radiation exposure on developmental instability in grasshoppers

Mutagenic and epigenetic effects of environmental stressors and their transgenerational consequences are of interest to evolutionary biologists because they can amplify natural genetic variation. We studied the effect of parental exposure to radioactive contamination on offspring development in lesser marsh grasshopper Chorthippus albomarginatus. We used a geometric morphometric approach to measure fluctuating asymmetry (FA), wing shape and wing size. We measured time to sexual maturity to check whether parental exposure to radiation influenced offspring developmental trajectory and tested effects of radiation on hatching success and parental fecundity. Wings were larger in early maturing individuals born to parents from high radiation sites compared to early maturing individuals from low radiation sites. As time to sexual maturity increased, wing size decreased but more sharply in individuals from high radiation sites. Radiation exposure did not significantly affect FA or shape in wings nor did it significantly affect hatching success and fecundity. Overall, parental radiation exposure can adversely affect offspring development and fitness depending on developmental trajectories although the cause of this effect remains unclear. We suggest more direct measures of fitness and the inclusion of replication in future studies to help further our understanding of the relationship between developmental instability, fitness and environmental stress.

Acute exposure to low-dose radiation disrupts reproduction and shortens survival of Wasmannia auropunctata (Hymenoptera: Formicidae) queens

Irradiation is a postharvest quarantine treatment option to control ants and other hitchhiker pests on fresh horticultural products exported from Hawaii. The radiotolerance of the invasive little fire ant, Wasmannia auropunctata (Roger) (Hymenoptera: Formicidae: Myrmicinae), was studied to determine a dose sufficient for its control. Queens from each of five laboratory microcolonies started from five geographic locations in Argentina were irradiated at 20, 50, 70, or 100 Gy or left untreated as controls and then followed for 13 wk to observe colony growth. In general, queen survivorship, and the number of eggs, larvae, and pupae observed in the microcolonies decreased with increasing irradiation dose. In the 50-, 70-, and 100-Gy treatments, the number of eggs observed was reduced by 68, 66, and 76%, respectively, compared with untreated control microcolonies. The number of larvae in the 50-, 70-, and, 100-Gy treatments was reduced by 99.6%, and only one pupa was observed in the 50-Gy treatment and none in the 70- and 100-Gy treatments during the 13-wk experiment. Queens in the 100-Gy treatment had significantly reduced longevity compared with queens in the other treatments. Radiation doses > or = 70 Gy stopped reproduction in W. auropunctata queens and should be sufficient as a phytosanitary treatment. Information from additional invasive ants in Myrmicinae and other subfamilies is needed before recommending a generic irradiation treatment for ants.

Genotype-independent transmission of transgenic fluorophore protein by boar spermatozoa

Recently, we generated transposon-transgenic boars (Sus scrofa), which carry three monomeric copies of a fluorophore marker gene. Amazingly, a ubiquitous fluorophore expression in somatic, as well as in germ cells was found. Here, we characterized the prominent fluorophore load in mature spermatozoa of these animals. Sperm samples were analyzed for general fertility parameters, sorted according to X and Y chromosome-bearing sperm fractions, assessed for potential detrimental effects of the reporter, and used for inseminations into estrous sows. Independent of their genotype, all spermatozoa were uniformly fluorescent with a subcellular compartmentalization of the fluorophore protein in postacrosomal sheath, mid piece and tail. Transmission of the fluorophore protein to fertilized oocytes was shown by confocal microscopic analysis of zygotes. The monomeric copies of the transgene segregated during meiosis, rendering a certain fraction of the spermatozoa non-transgenic (about 10% based on analysis of 74 F1 offspring). The genotype-independent transmission of the fluorophore protein by spermatozoa to oocytes represents a non-genetic contribution to the mammalian embryo.

Effective education in radiation safety for nurses

In order to establish an efficient training program of radiation safety for nurses, studies have been carried out on the basis of questionnaires. Collaboration of nurses, who are usually standing closest to the patient, is necessary in order to offer safe radiological diagnostics/treatment. The authors distributed the questionnaire to 134 nurses in five polyclinic hospitals in Japan. Important questions were: fear of radiation exposure, knowledge on the radiation treatment, understanding the impact on pregnancy, and so on. Most of the nurses feel themselves uneasy against exposure to radiation. They do not have enough knowledge of radiological treatment. They do not know exactly what is the impact of the radiation on pregnant women. Such tendency is more pronounced, when nurses spend less time working in the radiological department. Nurses play important roles in radiological diagnostics/treatment. Therefore, a well-developed education system for radiation safety is essential. The training for the radiation safety in medicine should be done in the context of general safety in medicine. Education programs in undergraduate school and at the working place should be coordinated efficiently in order to ensure that both nurses and patients are informed about the meaning of radiation safety.

Testicular function and fertility preservation in male cancer patients

The testis has been shown to be highly susceptible to the toxic effects of cancer therapy at all stages of life. Young cancer survivors are approximately half as likely as their siblings to sire a pregnancy. Radiation therapy to the testes and high cumulative dose of alkylating agents are the major factors decreasing the probability of fertility. This review aims to present an overview of the current state of knowledge in mechanisms how human spermatogonia proliferate and differentiate and how cancer therapy affects germ cells, what are the options for fertility preservation and what are the clinical risks and limitations related to such procedures. This area of research is discussed in the context of the potential future options that may become available for preserving fertility in male cancer patients.

Concomitant unilateral and synchronous bilateral testis cancer in azoospermic dizygotic twins: differential management of fertility preservation

OBJECTIVE

To optimize fertility preservation management in unilateral or bilateral testicular cancer.

DESIGN

Case series.

SETTING

Urology department and reproductive biology laboratory.

PATIENT(S)

Dizygotic azoospermic twins presenting unilateral and bilateral synchronous testicular tumors.

INTERVENTION(S)

Testicular sperm extraction (TESE) and orchiectomy.

MAIN OUTCOME MEASURE(S)

Semen analysis, histologic diagnosis.

RESULT(S)

No spermatozoa were cryopreserved for the first case, because fertility preservation was proposed after orchiectomy. Spermatozoa were retrieved after TESE for his brother with bilateral tumor.

CONCLUSION(S)

Clinicians should be aware of the need to recommend sperm banking before treatments may alter spermatogenesis. TESE may be the sole option for fertility preservation in bilateral testicular cancer.

Effects of dietary uranium on reproductive endpoints--fecundity, survival, reproductive success--of the fish Danio rerio

Exposure to metal-contaminated water has been shown to result in a number of reproductive abnormalities in adult and larvae fish, such as failure of oocyte maturation and teratogenic effects. Recently, dietary uptake of metals by fish has been recognized as a critical route of exposure, however, the mechanisms of metal uptake and toxicity are poorly understood and in need of further investigation. The objectives of the present study are to quantify uranium (U dietary transfers from spiked artificial diets) in Danio rerio tissues and embryos, as well as establish its effect on reproduction and embryonic development. Uranium's environmental prominence is currently increasing because of new mining and milling activities. Uranium concentrations range from 0.02 µg/L in natural waters to 2 mg/L. The focus of this study was to examine the trophic transfer and effects of U following exposure modalities (dose, exposure duration 1 to 20 d). Two different isotopes were used to distinguish between chemical and radioactivity toxicity of U. Results showed that U trophic transfer was low (0.52%). Uranium tissue distributions showed that accumulation occurred in digestive organs (liver, digestive tract) following dietary exposure. High levels of U were measured in the gonads (female in particular, >20% of relative burden). High U accumulation levels in eggs indicated maternal transfer of the contaminant. Moreover, U trophic exposure led to a reduction in reproduction success as a function of U accumulated levels. High U exposure conditions strongly reduced the total number of eggs (50%) and their viability at 10 d (reduction of the clutch number, low quality of eggs).

[Ecological and genetic monitoring of muridae from populations undergone to the chronic irradiation]

In work the data of long-term researches of consequences of chronic irradiation and radioactive pollution on a population of muridaea living in a zone of failure on the Chernobyl atomic power station and in territory of Northern radioecological station are resulted. It is shown, that chronic influence by investigated factors leads to authentically significant change of size of the genetic load determined on a level cytogenetic damages, intensity of reproduction, fertility.

An approach to the assessment of risk from chronic radiation to populations of European lobster, Homarus gammarus (L.)

The basic principles underlying a four-discrete age group, logistic, growth model for the European lobster Homarus gammarus are presented and discussed at proof-of-concept level. The model considers reproduction, removal by predation, natural death, fishing, radiation and migration. Non-stochastic effects of chronic low linear energy transfer (LET) radiation are modelled with emphasis on (99)Tc, using three endpoints: repairable radiation damage, impairment of reproductive ability and, at higher dose rates, mortality. An allometric approach for the calculation of LD(50/30) as a function of the mass of each life stage is used in model calibration. The model predicts that at a dose rate of 1 Gy day(-1), lobster population reproduction and survival become severely compromised, leading eventually to population extinction. At 0.01 Gy day(-1), the survival rate of an isolated population is reduced by 10%, mainly through loss of fecundity, comparable to natural migration losses. Fishing is the main ecological stress and only dose rates in the range 0.03-0.1 Gy day(-1) can achieve discernible effects above it. On the balance of radiation and other ecological stresses, a benchmark value of 0.01 Gy day(-1) is proposed for the protection of lobster populations. This value appears consistent with available information on radiation effects in wildlife.

Protection of ovarian tissue from radiotherapy

Advances researches in the diagnosis and treatment of childhood, adolescent and adult cancer have greatly increased the life expectancy of premenopausal women with cancer. However, one of the serious side effects of these treatments is the risk of damage to fertility. The ovaries are very sensitive to cytotoxic and radiotherapeutic treatment. The only established method of fertility preservation is embryo cryopreservation according to the Ethics Committee of the American Society for Reproductive Medicine (2005), but this option requires the patient to be of pubertal age, have a partner or use donor sperm, and be able to undergo a cycle of ovarian stimulation, which is not possible when the radiotherapy has to be initiated immediately or when stimulation is contraindicated according to the type of cancer. For patients who need immediate radiotherapy, cryopreservation of ovarian tissue is the only possible alternative. This manuscript reports the different techniques of cryopreservation and the results of transplantation of cryopreserved ovarian tissue. The current techniques allow cryopreservation of human ovarian fragments for a long time with good follicular survival rate after thawing. Numerous studies ultimately in this field have demonstrated to improve the survival rate of the oocytes and cryopreserved follicles. Moreover this manuscript includes a case of a 17-year-old girl who had to undergo pelvic irradiation for non-Hodgkin's lymphoma and the laparoscopic treatment to preserve the fertility (Fig. 2, Ref. 47).

Optimizing irradiation dose for sterility induction and quality of Bactrocera tryoni

The current study is an important step toward calibrating, validating, and improving irradiation methods used for Bactrocera tryoni (Froggatt) sterile insect technique (SIT). We used routine International Atomic Energy Agency/U.S. Department of Agriculture/Food and Agriculture Organization quality control tests assessing percentage of emergence, flight ability, sex ratio, mortality under stress, reproductive sterility, and sexual competitiveness, as well as a nonstandard test of longevity under nutritional stress to assess the impact of a range of target irradiation doses (60, 65, 70, 75, and 80 Gy) on the product quality of mass reared B. tryoni used in SIT. Sterility induction remained adequate (>99.5%) for sterile male-fertile female crosses, and 100% sterility was achieved in fertile male-sterile female crosses and sterile male-sterile female crosses for each irradiation doses tested. There was significant increase in mortality under stress as irradiation dose increased, and reduced participation in mating by males irradiated at higher doses. The current target-sterilizing dose for SIT of 70-75 Gy is associated with significant reduction in fly product "quality". Our data suggest that adequate sterility and improved fly quality could be achieved through a small reduction in target sterilizing dose.

Cryopreservation of ovarian tissue: an overview

Advances in the diagnosis and treatment of childhood, adolescent and adult cancer have greatly increased the life expectancy of premenopausal women with cancer. The ovaries are very sensitive to cytotoxic treatment, especially to alkylating agents. The only established method of fertility preservation is embryo cryopreservation according to the Ethics Committee of the American Society for Reproductive Medicine (2005), but this option requires the patient to be of pubertal age, have a partner or use donor sperm, and be able to undergo a cycle of ovarian stimulation, which is not possible when the chemotherapy has to be initiated immediately or when stimulation is contraindicated according to the type of cancer. For patients who need immediate chemotherapy, cryopreservation of ovarian tissue is the only possible alternative. This manuscript reports the techniques and results of orthotopic transplantation of cryopreserved ovarian tissue. Among almost 30 cases reported in the literature, seven live births have been achieved to date.

Effects of irradiation on Planococcus minor (Hemiptera: Pseudococcidae)

Irradiation has been recognized and endorsed as a potential phytosanitary measure that could be an alternative to current quarantine treatments. Dosages of 50, 100, 150, 200, and 250 Gy were used to irradiate three different life stages (eggs, immatures, and adults) of Planococcus minor (Maskell) (Hemiptera: Pseudococcidae), focusing on females due to its parthenogenesis ability, with an aim to find the most tolerant stage and the most optimal dose to control P. minor. Cobalt 60 was the source of irradiation used. Irradiation of 150-250 Gy has a significant effect on all life stages of P. minor, decreasing its survival rate, percentage of adult reproduction, oviposition, and fertility rate. The adult was the most tolerant life stage in both mortality and fertility rate. All the different irradiated target life stage groups oviposited eggs, but none of the F2 eggs hatched at the most optimal dosage of 150-250 Gy.

Influence of a 50 hz extra low frequency electromagnetic field on spermatozoa motility and fertilization rates in rabbits

Effects of a 50 Hz extra-low frequency electromagnetic field (ELF EMF) on in vitro rabbit spermatozoa motility were analyzed, as well as the effect on fertilization rates after insemination. Pooled semen samples and a control were exposed to 50 Hz ELF EMF. The difference of the samples of the test groups G1 and G2 with the control group CG (75.56%) for spermatozoa motility were found to be significant (P < 0.01). Differences were significant (P < 0.01) for curvilinear velocity (VCL) between the test group G3 (122.38 microm/s) and the control group CG (112.02 microm/s). Hormonally stimulated adult (9-12 months) females (n = 140) were inseminated with semen samples from G1, G2, G3 and CG (0.88 x 109 spermatozoa/0.5 mL average insemination portion) immediately after ELF EMF exposure and fertilization (kindling) rates were calculated. For the G2 it was 54.28% data indicate 50 Hz ELF EMF induced alterations of spermatozoa motility and kindling rate in rabbits, therefore influencing fertility.

Does brachytherapy of the prostate affect sperm quality and/or fertility in younger men?

OBJECTIVE

Sperm banking prior to surgical procedures which may affect fertility, such as retroperitoneal lymph node dissection, has been well documented. However, such procedures are usually performed in young men. With older men marrying later in life, or remarrying, we wanted to investigate the effects of radiation on prostate cancer patients who wanted to have children afterwards.

MATERIAL AND METHODS

We encountered several patients with prostate cancer who decided to undergo brachytherapy and were planning to have more children. We performed a search using PubMed and Ovid for the period 1966-2001 using the key words "fertility", "sperm banking", "radiation effects", "prostate cancer" and "brachytherapy".

RESULTS

Of the four young patients we encountered who underwent brachytherapy, we found no significant change in semen parameters post-therapy, and three of them were able to father a child subsequently without any deleterious side-effects. It has been demonstrated in several reports that external-beam radiation therapy is associated with decreased spermatogenesis due to Leydig cell dysfunction and decreased serum testosterone, as well as having a direct effect on spermatogonia. However, there is a scarcity of literature discussing the effects of prostate brachytherapy on spermatogenesis as the patients involved are usually older and usually do not desire to father any more children. As I has a half-life of 60 days, we used an exposure of 10 mR/h at the symphysis pubis and used integration to find the total dose exposed to the testis as follows: Limits 14 400 to 0, S 10e (-In2/1440.Tdt) where T = 14 400 and 20.75 R = 20.75 cGy. Therefore, the total dose was 20.75 cGy x 0.91 = 18.88 cGy. This value is considered too low to have any significant effect on testicular tissues.

CONCLUSIONS

We speculate that the effects of prostate brachytherapy on spermatogenesis in prostate cancer patients are minimal. However, due to the half-life of I, we recommend that these patients should wait for at least 3-4 months before trying to conceive. Furthermore, younger men with prostate cancer may want to consider sperm banking prior to brachytherapy if they want to have children in the future.

GONADAL EFFECT OF RADIATION FROM131I IN MALE PATIENTS WITH THYROID CARCINOMA

The role of iodine-131 therapy in the management of differentiated thyroid carcinoma is well established. Because the spermatogonia are very sensitive to radiation, there is concern that large doses of the latter could result in azoospermia and permanent infertility. For patients treated with a single ablation dose, testicular function recovers within months and the risk of infertility is diminished. Gonadal damage may be cumulative in those requiring multiple administrations. In all young male patients, but especially in those with metastatic or pelvic disease or both, the long-term storage of semen should be addressed prior to therapy. Sperm banking should be considered in patients likely to be given cumulative doses greater than 14 GBq of 131I. However, the patient's threshold for sperm banking might be even lower than that.

Male-mediated developmental toxicity in mice after 8 weeks'exposure to low doses of X-rays

PURPOSE

The aim of the study was to investigate the effects of subchronic irradiation of male mice on reproduction ability and induction of male-mediated teratogenesis.

MATERIALS AND METHODS

Male mice were irradiated to 0.05 Gy, 0.10 Gy and 0.20 Gy daily for 8 weeks, 5 days per week. The total doses were 2.00 Gy, 4.00 Gy and 8.00 Gy, respectively. After the end of exposure each male was caged with two untreated females. The females were sacrificed on day 17 based on the finding of a vaginal plug. Females were examined for the number of live and dead implantations and the incidence of congenital malformations of survival foetuses.

RESULTS

The fertilization ability of males was not diminished. The exposure to 0.20 Gy daily significantly decreased the percent of pregnant females and the number of total implantations. Exposure to 0.10 Gy and 0.20 Gy daily caused decreases in the number of live foetuses and induced dominant lethal mutations (over 50% at the highest dose). Exposure to each dose significantly enhanced the number of deaths (especially early) implants. The incidence of gross and skeletal malformations was not statistically significant, except for skeletal malformations at the highest dose.

CONCLUSIONS

Results confirmed that irradiation of male germ cells cause genetic effects which could be transmitted to the offspring. After subchronic exposure to low doses the majority of mutations caused premature death. Subchronic exposure to low doses of X-rays did not induce external and skeletal malformations of surviving foetuses.

Effects of a unique electromagnetic field system on the fertility of rats

The authors investigated the fertility of male and female rats exposed to a unique-design electromagnetic apparatus (Hivex Electromagnetic Field System-5 [EMFS-5]), which establishes an omni-directional, spatial field and has a wide band range of 100 MHz-3 GHz. We used 32 male and 32 female rats that were proven breeders. Sixteen rats from each sex were exposed to the EMFS for 8h/day for 10 days. The others were sham exposed. The rats were divided into the following 4 groups: in group AG1-AG8, males and females were exposed; in group AG9-AG16, only females were exposed; in group AG17-AG24, only males were exposed; and in group AG25-AG32, males and females were sham exposed. After exposure for each group, a male rat was cohabited with a female rat until parturition. The authors' results showed that except for 1 male, the fertility of all other rats was not affected. They did not see differences in reproductive ability (latency to parturition, litter size, number of male/female pups, male-to-female ratio, mass of pups at weaning) between experimental groups and the sham exposed group. The authors concluded that exposure of male and female rats to the Hivex EMFS-5 does not affect fertility or reproductive ability.

Male fertility and strategies for fertility preservation following childhood cancer treatment

Infertility in the male is a potential complication of childhood cancer treatment for long-term survivors. The risk is dependent primarily on the treatment used, but also on the underlying disease. Chemotherapy (especially alkylating agents) and radiotherapy, even in low doses, may damage the seminiferous epithelium and impair spermatogenesis in both children and adults. Leydig cell function and testosterone production are generally preserved after chemotherapy and low dose radiotherapy, whilst larger doses of radiotherapy may result in hypogonadism. Patients treated with potentially gonadotoxic treatments require regular multidisciplinary follow-up including assessment of puberty and gonadal function. Currently the only option available for fertility preservation in young males treated for cancer is semen cryopreservation. For pre-pubertal patients, techniques for fertility preservation remain theoretical and as yet unproven. These include hormonal manipulation of the gonadal environment before treatment, germ cell transplantation and testis xenografting, which have all shown promise in a variety of animal studies. Refinement of these techniques requires investigations in relevant animal models. In the present chapter we include data which suggest that the common marmoset (Callithrix jacchus) monkey, a New World primate, exhibits important parallels with human testicular development and may help us to understand why the pre-pubertal testis is vulnerable to effects of cytotoxic therapy on future fertility.

[Comparison of the ability to fertilize females by Hyalomma anatolicum anatolicum males irradiated with gamma radiation from caesium 137 with non-irradiated males]

In this study, Hyalomma anatolicum anatolicum male ticks were subjected to gamma radiation with a dose of 10 Gy emitted by a gamma-ray source of Caesium 137. Female ticks were divided into 3 groups and placed in rabbit ears to feed. In the first group, the females fed with normal and irradiated males, in the second group females fed only with irradiated males and in last group females fed with normal males. Biological parameters such as the feeding period, weights, period of time from dropping until egg-laying began, the number of eggs and the number of larva hatching from eggs were recorded. With the results of statistical analysis it was found that the average egg laying period of females in the second group was clearly less (22.77 days) than other groups and the difference between these groups was statistically important (P < 0.05). After evaluation of numbers of larva, also there was a statistically important difference between the groups and the average number of larva was clearly higher (2519.30) in third group than other groups. In conclusion, in this study it was found that irradiated males could not compete with normal males in mating with females and because of this they couldn't affect the feeding and reproductivity of females.

Fertility preservation in cancer patients using stored ovarian tissue: clinical aspects

PURPOSE OF REVIEW

This review covers the medical approach and laboratory guidelines needed for fertility preservation using stored ovarian tissue in cancer patients. Indications, careful patient selection and timing are essential. Techniques for tissue harvesting and storage are evaluated. Up-to-date information on publications reporting on transplantation, recovery of endocrine function, pregnancy and delivery of healthy babies is reviewed as well as relevant data on safety measures to detect cancer cells in stored ovarian tissue.

RECENT FINDINGS

Recent literature review indicates 12 pregnancies, five deliveries of healthy babies and two ongoing pregnancies after transplantation of ovarian tissue using different methods. To increase the safety of ovarian tissue cryopreservation-reimplantation procedures, algorithm and methods to identify tumor involvement in the ovaries and detection of small numbers of cancer cells in ovarian tissue were recently reported.

SUMMARY

Cryopreservation of ovarian tissue has been practiced for over a decade in an attempt to preserve fertility before the commencement of potentially sterilizing chemotherapy. With more than a few recent reports on pregnancies and deliveries after transplantation of ovarian tissue, there will be more patients requesting the storage of ovarian tissue in order to preserve fertility prior to cancer treatments.

Effect of irradiation on mating ability in the male sweetpotato weevil (Coleoptera: Curculionidae)

The sterile insect technique (SIT) is widely used for suppressing or eradicating target pest insect populations. The effectiveness of SIT depends on the ability of released sterile males to mate with and inseminate wild females. Irradiation is the effective manner to sterilize mass-reared insects. The negative impacts of this procedure are not limited to damage on reproductive cells. Gamma-radiation damages the epithelial tissue of midgut, which affects the alimentation in insects. Irradiated males alter their mating behavior over time because of the depression of metabolic activity by sterilization. In this study, we evaluated the male mating performance and sexually compatibility of irradiated male Cylas formicarius elegantulus (Summers) (Coleoptera: Curculionidae) with a 200-Gy dose, as currently used in the SIT program in Okinawa Prefecture, throughout 16 d after irradiation in the laboratory. The mating ability of irradiated males did not differ from that of control males for about a week. However, the mating ability of irradiated male drastically decreased thereafter. We consider that irradiated male C. formicarius elegantulus with a 200-Gy dose had no major effect on male mating behavior approximately for a week after irradiation.

[Fertility preservation in adolescent cancer patients]

Recent advances in cancer therapy have improved the survival rate of infant and adolescent facing cancers. The objective of treatment is not only to cure cancer but also to limit its secondary consequences. Impaired fertility is an important sequel of numerous treatments against cancer. Therefore, efforts to maintain fertility must be a major consideration in the treatment plan. This review focuses on various options for preserving fertility in adolescents. In female patients, ovarian transposition out of the radiation field may considerably reduce the radiation received by the ovaries. The benefits of GnRH analogue are not yet clear and apoptosis inhibiting agents are unavailable. Embryo freezing is the most reliable method to preserve fertility. This method is time-intensive, requires a partner, and ovarian stimulation may not always be compatible with the need of starting treatment against cancer immediately. Oocyte cryopreservation is an experimental technique that can be used in post-pubertal patients irrespective of their marital status. The cryopreservation of mature oocytes has similar constrains as embryo freezing ; in addition the technique is not as well-established and the pregnancy rates obtained are much lower than those achieved with embryos. Freezing of immature oocytes followed by in vitro maturation in spite of its theoretical advantages is inefficient in current practice. Ovarian tissue cryopreservation offers great hope because it has the potential to preserve a large number of primordial follicles without any ovarian stimulation and preliminary trials have shown some success. For male adolescents cancer patients semen cryopreservation is a successful alternative that should be offered systematically when cancer therapies that may impair gonadal function are indicated. For prepubertal males there is presently no standardized technique for preserving fertility ; however, the development of testicular germ-cell harvest needs to be considered.

DDB2, DDB1A and DET1 exhibit complex interactions during Arabidopsis development

Damaged DNA-binding proteins 1 and 2 (DDB1 and DDB2) are subunits of the damaged DNA-binding protein complex (DDB). DDB1 is also found in the same complex as DE-ETIOLATED 1 (DET1), a negative regulator of light-mediated responses in plants. Arabidopsis has two DDB1 homologs, DDB1A and DDB1B. ddb1a single mutants have no visible phenotype while ddb1b mutants are lethal. We have identified a partial loss-of-function allele of DDB2. To understand the genetic interaction among DDB2, DDB1A, and DET1 during Arabidopsis light signaling, we generated single, double, and triple mutants. det1 ddb2 partially enhances the short hypocotyl and suppresses the high anthocyanin content of dark-grown det1 and suppresses the low chlorophyll content, early flowering time (days), and small rosette diameter of light-grown det1. No significant differences were observed between det1 ddb1a and det1 ddb1a ddb2 in rosette diameter, dark hypocotyl length, and anthocyanin content, suggesting that these are DDB1A-dependent phenotypes. In contrast, det1 ddb1a ddb2 showed higher chlorophyll content and later flowering time than det1 ddb1a, indicating that these are DDB1A-independent phenotypes. We propose that the DDB1A-dependent phenotypes indicate a competition between DDB2- and DET1-containing complexes for available DDB1A, while, for DDB1A-independent phenotypes, DDB1B is able to fulfill this role.

[Long-term exposure to low intensity microwave radiation affects male reproductivity]

OBJECTIVE

To evaluate the effect of Long-term exposure to low intensity microwave radiation on male reproductivity.

METHODS

A total of 289 married male radar operators were included in the radar group and 148 married men unexposed to microwave radiation were enrolled as controls. Questionnaires were used and the intensity of microwave radiation in different working areas was detected.

RESULTS

The rate of sexual dysfunction was 43.6% in the radar group and 24.4% in the control group (P < 0.01). The natural pregnancy rate was 53.6% within 1 year of marriage and 46.4% after 1 year of marriage in the radar group, as compared with 81.1% and 18.9% in the control group (P < 0.01).

CONCLUSION

Long-term exposure to low intensity microwave radiation evidently increased the sexual dysfunction rate and decreased natural pregnancy rate in men.

[Estimation of the efficiency of seed irradiation by thermal neutrons for inducing chromosomal aberrations in M1 of cotton Gossypium hirsutum l]

Exposure of cotton seeds to thermal neutrons at doses of 15, 25, and 35 Gy was shown to induce many altered plants, including sterile and chimeric ones. Most of these phenotypic changes were shown to result from novel genomic, chromosomal, and desynaptic mutations. The presence of these mutations in the karyotype of M, plants often decreased meiotic index and pollen fertility. In translocation forms, the decrease in pollen fertility was caused by the prevalence of quadrivalents in form of rings and chains with adjacent segregation of chromosomes from the translocation complexes. Based on the shapes and sizes of multivalent associations, we performed preliminary localization of translocation breakpoints. A specific feature of the effect of thermal neuron irradiation in M1 was induction of numerous unique chromosomal aberrations, consisting in the appearance in the same plant of several types of mutations (genomic and chromosomal), exchange complexes in the same nucleus, and multiple exchanges involving three nonhomologous chromosomes.

Radiation-induced untargeted germline mutations in Japanese medaka

Radiation has been shown to increase mutation frequencies at tandem repeat loci by indirect interactions of radiation with DNA. We studied germline mutations in chronically exposed Japanese medaka (Oryzias latipes) using microsatellite loci. After screening 26 randomly selected loci among unirradiated parents and their 200 offspring, we selected seven highly mutable loci (0.5-1.0 x 10(-2) mutants per locus per gamete) and two bonus loci for further study. To determine if radiation exposure increases mutation frequencies in these loci, medaka were chronically irradiated from subadults through maturation at relatively low dose rates of 68 mGy/d. Total doses for males and females were 10.4 and 3 Gy, respectively. The mean number of mutations for the offspring of exposed families (0.149+/-0.044) was significantly higher (P=0.018) than for control families (0.080+/-0.028), indicating induction of germline mutations from chronic irradiation. This increase in the microsatellite mutation rate is greater than expected from direct interaction of radiation with DNA, suggesting indirect, untargeted mechanism(s) for mutations. This study identified microsatellite loci with a high mutational background in medaka, variation among loci and families as important variables, and demonstrated the usefulness of this fish model for studying radiation-induced germline mutations.

Isolation of germ cells from leukemia and lymphoma cells in a human in vitro model: potential clinical application for restoring human fertility after anticancer therapy

More than 70% of patients survive childhood cancer, but chemotherapy and radiation therapy may cause irreversible impairment of spermatogenesis. To treat infertility secondary to anticancer treatment for childhood cancer, we have developed a procedure to isolate germ cells from leukemic mice by fluorescence-activated cell sorting with two surface markers, and transplantation of isolated germ cells successfully restored fertility without inducing leukemia. In the present study, we analyzed human germ cells and human malignant cells, including five leukemia cell lines and three lymphoma cell lines, by fluorescence-activated cell sorting with antibodies against MHC class I and CD45. Testicular specimens were obtained from a patient who underwent surgery for testicular rupture. In the high forward scatter and low side scatter region, no malignant cells were found in the MHC class I-negative and CD45-negative fraction (the germ cell fraction), with the exception of K562 cells. A total of 39.2% of the germ cells were found in the germ cell fraction. A total of 1.45% of K562 cells were found in the germ cell fraction. Treatment with IFNgamma induced the expression of MHC class I on K562 cells but not on germ cells and made it possible to isolate germ cells from K562 cells. In conclusion, we isolated human germ cells from malignant cells with two surface markers after treatment with IFNgamma. Immunophenotyping for each patient will be necessary before isolation and induction of surface marker will be clinically applicable.

[Life expectency and fertility of postembrio stage drosophila after the pulse-periodic X-ray irradiation]

The effect of 13 Hz repetition rate X-ray pulses with 3 x 10(-6)-1.5 x 10(-4) Gr per pulse dose during 5 minute on drosophila's larvae and on pupae vas investigated. It was shown that the effect depends on drosophila's age as well as on X-ray dose and manifests itself in variation of life expectancy and fertility.

Attitudes and practices of pediatric oncology providers regarding fertility issues

PURPOSE

Given the higher survival rates of childhood cancer, health care providers must be aware of the side effects of cancer therapies to educate patients and provide appropriate interventions to reduce cancer-related morbidity. To understand the current practices and attitudes in a pediatric hematology/oncology clinic, health care providers were surveyed regarding fertility issues pertinent to their patient care. PARTICIPANTS AND INSTRUMENTS: In this study, 93.8% (30/32) health care providers in one pediatric hematology/oncology department completed a 44-item survey assessing knowledge, current practices, obstacles to current practices, perceptions of patient differences, and improvements to future practice.

RESULTS

The majority of health care providers were aware of the adverse effects of alkylating agents (90.7%) and of abdominal and pelvic radiation (100.0%) on fertility. However, only half were aware of gender differences in gonadotoxicity (50.0%) or knowledgeable of current research and technology in fertility preservation (53.3%). While only 34.6% of providers currently consulted with specialists, nearly all (92.8%) indicated a desire to do so in the future, but 64.3% indicated difficulties in finding proper facilities and specialists for their patients. Almost all (96.6%) agreed that providers and patient families need more information regarding the effects of cancer therapy on fertility.

CONCLUSIONS

Surveyed pediatric oncology providers considered fertility to be an important issue for childhood cancer patients and desired more resources regarding effects on fertility and fertility preservation. Greater communication needs to be established between pediatric oncology providers and specialists in reproductive medicine and endocrinology to ensure adequate professional collaboration and patient referrals.

Caspase-2 involvement during ionizing radiation-induced oocyte death in the mouse ovary

In mammals, the pool of primordial follicles at birth is determinant for female fertility. Exposure to IR during oogonia proliferation and the diplotene stages of ovarian development induced the virtual disappearance of primordial follicles in the postnatal ovary, while half the follicular reserve remained present after irradiation during the zygotene/pachytene stages. This sensitivity difference was correlated with the level of caspase-2 expression evaluated by immunohistochemistry. At the diplotene stage, Western blot and caspase activity analysis revealed that caspase-2 was activated 2 h after irradiation and a significant increase in the number of oocytes expressing cleaved caspase-9 and -3 occurred 6 h after treatment. Inhibition of caspase-2 activity prevented the cleavage of caspase-9 and partially prevented the loss of oocytes in response to irradiation. Taken together, our results show that caspase-2-dependent activation of the mitochondrial apoptotic pathway is one of the mechanisms involved in the genotoxic stress-induced depletion of the primordial follicle pool.

Long-term Events in Adult Patients with Clinical Stage IA-IIA Nonbulky Hodgkin's Lymphoma Treated with Four Cycles of Doxorubicin, Bleomycin, Vinblastine, and Dacarbazine and Adjuvant Radiotherapy: A Single-Institution 15-Year Follow-up

PURPOSE

To report on long-term events after short doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) chemotherapy and adjuvant radiotherapy in favorable early-stage Hodgkin's lymphoma.

EXPERIMENTAL DESIGN

We monitored late events and causes of death over 15 years (median follow-up, 120 months) in 120 patients with nonbulky stage IA-IIA Hodgkin's lymphoma, treated with four cycles of ABVD and limited radiotherapy. Pulmonary and cardiac function tests were done throughout the follow-up. Outcome measures included cause-specific mortality, standardized mortality ratio, and standardized incidence ratio for secondary neoplasia.

RESULTS

Projected 15-year event-free and overall survival were 78% and 86%, and tumor mortality was 3%. Standardized mortality ratio was significantly higher than 1 for both males (2.8; P=0.029) and females (9.4; P=0.003). The risk of cardiovascular events at 5 and 12 years was 5.5% and 14%, with a median latent time of 67 months (range: 23-179 months) from the end of radiotherapy. Pulmonary toxicity developed in 8% of patients; all had received mediastinal irradiation and the median time from radiotherapy to pulmonary sequelae was 76 weeks (range: 50-123 weeks). The risk of secondary neoplasia at 5 and 12 years was 4% and 8%, respectively, with no cases of leukemia. Fertility was preserved.

CONCLUSIONS

Long-term events were mostly related to radiotherapy; the role of short ABVD chemotherapy was very limited, as documented by fertility preservation and lack of secondary myelodysplasia/leukemia. A proportion of patients died from causes unrelated to disease progression and the excess mortality risk was mostly due to the occurrence of secondary neoplasms and cardiovascular diseases. A moderate dose reduction of radiotherapy from 40-44 Gy to 30-36 Gy did not decrease the risk of late complications; abolishing radiotherapy in nonbulky early-stage Hodgkin's lymphoma is being evaluated.

Effect of electromagnetic nanopulses on C. elegans fertility

Electromagnetic nanopulse exposure results in decreased fertility of C. elegans, a well studied, multicellar organism. Experiments indicate that this effect is unlikely to be due to heating. Instead, nanopulses interfere with fertilization or development by an as yet undetermined mechanism. Study of nanopulse exposure of C. elegans could help to understand more generally how living organisms interact with electromagnetic fields.

The effect of cancer treatment on female fertility and strategies for preserving fertility

Aggressive chemotherapy and radiotherapy in young patients with cancer has greatly enhanced the life expectancy of these patients, but these treatments often cause infertility because of the massive destruction of the ovarian reserve resulting in premature ovarian failure (POF). This review focuses on the effect of cancer treatments on fertility and on the various surgical and assisted-reproduction innovations that are available to provide the patient with the option of future pregnancies. As the emerging discipline of fertility preservation is steadily attracting increasing interest, developments in the near future promise to be very exciting. However, in everyday routine work, better interdisciplinary cooperation between gynecological and pediatric oncologists, surgeons, immunologists and endocrinologists is necessary so that individualized options for fertility preservation can be offered in advance of surgical procedures or cancer treatments. GnRH analog treatment can preserve fertility in some patients, but not in all. At present, cryopreservation of ovarian tissue appears as a very promising method of providing the cancer patient with a realistic chance of preserving fertility-a prospect that is also extremely important to patients for psychological reasons.