La importancia del sexo fetal en la ecografía morfológica: genitales ambiguos y disgenesia gonadal mixta / The importance of fetal sex in morphological ultrasound: ambiguous genitalia and mixed gonadal dysgenesis

La identificación del sexo fetal forma parte de la ecografía de segundo trimestre. En ocasiones se presentan anomalías genitales que no permiten definirlo adecuadamente, lo que se conoce como genitales ambiguos. La importancia de los mismos se debe a su asociación con desórdenes del desarrollo sexual, patologías más complejas y graves. En la mayoría de casos el diagnóstico y el manejo es postnatal, estando bien establecido. El diagnóstico prenatal, en cambio, es poco frecuente, limitado y menos conocido. Presentamos el caso de una gestante de 20 años con el hallazgo de genitales ambiguos en semana 29 y posteriormente se diagnosticó de disgenesia gonadal mixta (AU)

Fetal sex identification is a well-established part of the second trimester ultrasound. Sometimes there are genital abnormalities that prevent proper identification, called ambiguous genitalia. Its importance is based on its association with development sex disorders, a far more severe and complex diseases. In most of the cases, diagnosis and management are postnatal and well systematized. Prenatal diagnosis, however, is less frequent and more limited. We present the case of a 20 year old pregnant with a finding of ambiguous genitalia at 29 week and a diagnosis of mixed gonadal dysgenesis (AU)

Trends in lung cancer incidence by histologic subtype in the south of Spain, 1985-2012: a population-based study

Purpose: To analyze and interpret age- and sex-specific incidence trends of lung cancer in Granada over the period 1985–2012 and to further analyze these trends by histologic subtype. Methods: Incidence data were obtained from the population-based cancer registry located in Granada (Southern Spain). All cases with newly diagnosed primary lung cancer over the period 1985–2012 (n = 8658) and defined by International Classification of Diseases 10th Revision (codes C33–C34) were included. Joinpoint regression analysis of age-standardized incidence rates was used to estimate the annual percent change (APC) and 95 % confidence intervals. Results are presented overall and by sex, age groups (0-34, 35-54, 55-64, 65-74, C75 years) and histologic subtypes. Results: Temporal trends of incidence rates by sex, over the period 1985–2012, showed a distinct pattern. A significant change point of the trend was observed in males in 1994 (APC: ?2.5 %; 95 % CI 0.7-4.4 from 1985 to 1994 and -1.4 %; 95 % CI -2.0 to -0.7 from 1994 onward). This general change was mainly caused by the age group 65-74 years and by the higher incidence of squamous cell carcinoma histologic subtype. In females, lung cancer incidence increased over the entire study period by +4.2 % per year (95 % CI 3.1-5.4); this trend was mainly caused by the age group 55-64 years (APC = +7 %) and by adenocarcinoma incidence between women (APC = +6.8 %). Conclusion: Male lung cancer incidence rates have decreased in Granada, while female rates have increased overall especially in younger women. These trends may reflect the increased consumption of cigarettes in women especially during younger ages. Lung cancer prevention through tobacco control policies are therefore of utmost importance (AU)

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Updating control of puberty in male European sea bass: A holistic approach.

Puberty is the process by which an immature animal acquires the ability to reproduce for the first time; its onset occurs soon after sexual differentiation and is characterized by the beginning of gametogenesis in both sexes. Here we present new insights on when and how the onset of puberty occurs in male European sea bass, its dependence on reaching a critical size, and how it can be controlled by photoperiod, revealing the existence of a photolabile period with important applications in aquaculture. Regarding size, apparently only European sea bass above a certain size threshold attain the ability to carry out gametogenesis during their first year of life, while their smaller counterparts fail to do so. This could imply that fish need to achieve an optimal threshold of hormone production, particularly from the kisspeptin/Gnrh/Gth systems, in order to initiate and conclude puberty. However, a long-term restricted feeding regime during the second year of life did not prevent the onset of puberty, thus suggesting that the fish are able to maintain the reproductive function, even at the expense of other functions. Finally, the study of daily hormonal rhythms under different photoperiod regimes revealed the equivalence between their core values and those of seasonal rhythms, in such a way that the daily rhythms could be considered as the functional units of the seasonal rhythms.

Neuronal synaptic outputs determine the sexual fate of postsynaptic targets.

Synapses mediate inductive interactions for the proper development of pre- and postsynaptic cells: presynaptic electrical activities and synaptic transmission ensure the organization of postsynaptic structures, whereas neurotrophins produced in postsynaptic cells support the survival and enlargement of presynaptic partners. In Drosophila, a motor nerve has been implicated in the induction of the muscle of Lawrence (MOL), the formation of which is male specific and depends on the neural expression of fruitless (fru), a neural sex-determinant gene. Here we report the identification of a single motoneuron essential for inducing the MOL, which we call the MOL-inducing (Mind) motoneuron. The MOL is restored in fru mutant males, which otherwise lack the MOL, if the fru(+) transgene is selectively expressed in the Mind motoneuron by mosaic analysis with a repressible cell marker. We further demonstrate that synaptic outputs from the Mind motoneuron are indispensable to MOL induction, because the blockage of synaptic transmission by shibire(ts) (shi(ts)) during the critical period in development abolished the MOL formation in males. Our finding that sex-specific neurons instruct sexually dimorphic development of their innervating targets through synaptic interactions points to the novel mechanism whereby the pre- and postsynaptic partners coordinately establish their sexual identity.

Photons and evolution: quantum mechanical processes modulate sexual differentiation.

This paper will show that the fractional difference in the human gender ratio (GR) between the GR(at death) for those born in solar cycle peak years (maxima) and the GR(at death) in those born in solar cycle non-peak years (minima), e.g., 0.023, divided by Pi, yields a reasonable approximation of the quantum mechanical constant, alpha, or the fine structure constant (FSC) approximately 0.007297... or approximately 1/137. This finding is based on a sample of approximately 50 million cases using common, readily available demographic data, e.g., state of birth, birth date, death date, and gender. Physicists Nair, Geim et al. had found precisely the same fractional difference, 0.023, in the absorption of white light (sunlight) by a single-atom thick layer of graphene, a carbon skeleton resembling chicken wire fencing. This absorption fraction, when divided by Pi, yielded the FSC and was the first time this constant could "so directly be assessed practically by the naked eye". As the GR is a reflection of sexual differentiation, this paper reveals that a quantum mechanical process, as manifested by the FSC, is playing a role in the primordial process of replication, a necessary requirement of life. Successful replication is the primary engine driving evolution, which at a biochemical level, is a quantum mechanical process dependent upon photonic energy from the Sun. We propose that a quantum-mechanical, photon-driven chemical evolution preceded natural selection in biology and the mechanisms of mitosis and meiosis are manifestations of this chemical evolution in ancient seas over 3 billion years ago. Evolutionary processes became extant first in self-replicating molecules forced to adapt to high energy photons, mostly likely in the ultraviolet spectrum. These events led to evolution by natural selection as complex mixing of genetic material within species creating the variety needed to match changing environments reflecting the same process initiated at the dawn of life. Both evolutionary mechanisms coexist and are interactive. The periodic energy of solar maxima is likely modulating the human genome from maternal integument to an embryo in utero with non-local mechanisms intrinsic to quantum mechanics.

Induction of gynogenesis in muskellunge with irradiated sperm of yellow perch proves diploid muskellunge male homogamety.

Diploid gynogenesis was induced in muskellunge Esox masquinongy using UV-irradiated muskellunge sperm as the first step in producing monosex females. In this approach, we have to rely on negative controls as an indirect reference for sperm genetic material destruction. In the first experiment, equal proportions of gynogenetic females and males were produced. Negative controls, UV-irradiated sperm without heat shock, yielded some normal hatching larvae, described as spontaneous diploids. In the second experiment, muskellunge eggs were activated using sperm from yellow perch. Because hybrids between these species are not viable, we produced unambiguous gynogens. When UV-irradiated yellow perch sperm was used to inseminate muskellunge eggs, haploids resulted (22.5% +/- 2.8% survival to the eyed stage). To produce diploid gynogens, a heat shock of 31 degrees C was applied to inseminated eggs 20 min after activation for a duration of 6 min. This process yielded several hundreds of gynogens for rearing. Several treatments of masculinizing hormone, 17alpha-methyltestosterone (MT), were carried out. Fish were dissected and gonads examined histologically for sex determination. Gynogens produced using yellow-perch sperm confirmed the presence of males in the control group, whereas the MT bath treatment (400 microg/liter) resulted in the production of fish with ovotestis. These results provide evidence for male homogamety in muskellunge and imply that a change of strategy is needed to produce monosex populations.

Genes involved in light control of sexual differentiation in Chlamydomonas reinhardtii.

Gamete formation requires the sequential action of two extrinsic cues, nitrogen deprivation and blue light. The mutants described here are specifically altered in the light-dependent step. Mutations lrg1, lrg3, and lrg4 overcome this light dependence while mutation lrg2 results in a delayed execution of the light-mediated step. The four mutations are linked. The recessive nature of the lrg1, lrg3, and lrg4 mutations implies that they encode elements of negative control in this light response pathway. Analyses of diploids suggest an interaction between the gene products of the mutated loci with a central role for lrg4. The lrg4 mutation is unique also because it overcomes the light dependence of Chlamydomonas zygote germination when present in homozygous form. These data indicate that there are common components in the signal chains that control gametogenesis and zygote germination.

Prenatal exposure to a low-frequency electromagnetic field demasculinizes adult scent marking behavior and increases accessory sex organ weights in rats.

Pregnant Sprague-Dawley dams were exposed to a low-level, low-frequency pulsed electromagnetic (EM) field (15 Hz, 0.3 msec duration, peak intensity 8 gauss) for 15 min twice a day from day 15 through day 20 of gestation, a period in development that is critical for sexual differentiation of the male rat brain. No differences in litter size, number of stillborns, or body weight were observed in offspring from field-exposed dams. At 120 days of age, field-exposed male offspring exhibited significantly less scent marking behavior than controls. Accessory sex organ weights, including epididymis, seminal vesicles, and prostate, were significantly higher in field-exposed subjects at this age. However, circulating levels of testosterone, luteinizing hormone, and follicle-stimulating hormone, as well as epididymal sperm counts, were normal. These data indicate that brief, intermittent exposure to low-frequency EM fields during the critical prenatal period for neurobehavioral sex differentiation can demasculinize male scent marking behavior and increase accessory sex organ weights in adulthood.

Gonadal differentiation in frogs, Rana japonica and R. brevipoda, raised from UV irradiated eggs.

The gonadal differentiation of anurans, Rana japonica and R. brevipoda, was examined in animals raised from eggs which had been irradiated at the vegetal hemisphere with UV (9300 erg/mm2) at the 2-cell stage. In R. japonica about 70% of the larvae at stage I from the pressed and UV-irradiated eggs were germ cell free, but at a stage immediately after metamorphosis all animals had at least some germ cells, although their gonads often were extremely small and poorly differentiated. When male animals matured sexually, many of them had abnormal gonads. However, all of them were shown by artificial means to be capable of fertilization. In the nonpressed and irradiated group, no larvae were germ cell free and the animals immediately after metamorphosis showed nearly normal gonadal differentiation except for the presence of a few degenerate oocytes in the ovaries. The results in R. brevipoda were basically similar to those in R. japonica. In both species, sex ratios were determined at two stages, the first immediately after metamorphosis and the other when the animals matured, as based on gonad morphology and histology and on external sexually dimorphic characters as well. Sex ratios at these two stages in frogs from the pressed and irradiated eggs differed markedly in R. brevipoda. The ratio was normal at metamorphosis but high M/F ratios occurred when animals became mature. That sex reversal took place in this species as well as in R. japonica (in which sex-ratio deviation was not statistically significant) was supported by the sex ratios of the progenies of these supernumerary males.