Thyroid hormone receptors and ligand, tissue distribution and sexual behavior

The thyroid hormones (THs) triiodothyronine (T3) and tetraiodothyronine, or thyroxine (T4), not only dramatically impact on development and differentiation, but also on the sexual and reproductive function. There is large body of literature, in fact, on the effects of THs on the reproductive function in both humans (Poppe and Velkeniers, 2004; Wajner et al., 2009) and animals (Hapon et al., 2010; Nelson et al., 2011). For a long time the gonads were thought to be unresponsive to THs, but TH receptors (TR) were discovered in rat (Jannini et al., 1990; Palmero et al., 1988) and then in human testis (Jannini et al., 2000). In women, the association of menstrual disturbance with thyroid disease was described as early as 1840 by von Basedow, but the discovery of TRs in the ovary was carried out at the end of last century (Wakim et al., 1994b). Therefore, the link between thyroid and reproductive function was well established. Since then, research has shown that thyroid dysfunction is associated with an adverse effect on fertility, both in men (Wagner et al., 2009) and women (Dittrich et al., 2011). There is also evidence that THs can affect the sex steroid hormone axis (Bagamasbad and Denver, 2011), consequently sexual hormones and the pituitary gland can mediate the action of THs on the reproductive physiology. While the effects of THs on fertility have been widely studied, little is known about their influence on sexual function. In the last few years, an increasing number of evidences have shown the influence of THs on male sexual function, particularly on ejaculation control as well on desire and erectile function (Carani et al., 2005; Corona et al., 2012b; Di Sante et al., 2016). The female sexual function and the relationship with thyroid function is still less studied. Furthermore, studies conducted on animals have shown the presence of TRs in the male (Carosa et al., 2010) and female genitalia (Rodriguez-Castelan et al., 2017). Moreover, knockout mice for TRs showed alterations in sexual behavior (Dellovade et al., 2000). The purpose of this review is to summarize and discuss the available data on the influence of THs on male and female sexual function to understand the molecular mechanisms of the influence of the thyroid gland on sexual behavior and function

Response regarding Existential Issues in Sexual Medicine. The relation between death anxiety and hypersexuality

The recent article published by Dr Watter, “Existential Issues in Sexual Medicine: The Relation Between Death Anxiety and Hypersexuality,” deals with an interesting issue: the unique relation between death and sexuality

The sentiment analysis of tweets as a new tool to measure public perception of male erectile and ejaculatory dysfunctions

Twitter is a social network based on "tweets," short messages of up to 280 characters. Social media has been investigated in health care research to ascertain positive or negative feelings associated with several conditions but never in sexual medicin

Composição e história natural das serpentes de Cerrado de Itirapina, São Paulo, sudeste do Brasil

Neotropical snake assemblages present high species richness and complex structures. The Cerrado is the second largest biome in Brazil, and was included among the 25 World's biodiversity hotspots. In southeastern Brazil, the remnant Cerrado areas have suffered intense destruction, and presently less than 2% of Cerrado natural vegetation remain in São Paulo state. Virtually no detailed study on Cerrado snakes was carried out in this region. The Itirapina region has one of the last well preserved remnants of open cerrado in São Paulo state. Our purpose in this work was the study of natural history and composition of the Cerrado snakes of Itirapina region. We performed an extensive field sampling combining six sampling methods in Estação Ecológica de Itirapina and disturbed Cerrado areas in its surroundings (municipalities of Itirapina and Brotas), during 101 trips throughout 43 months, between September 1998 and March 2002, corresponding to 446 days of field sampling. We also collected additional data from museum specimens housed in scientific collections. We present data on size, general abundance, habitat and macrohabitat use, daily and seasonal activity, feeding, reproduction, and defense. We also compared the Itirapina snake assemblage with nine snake assemblages of Brazil, from Amazonia, Atlantic Forest, Cerrado, and other open habitats. We recorded a total of 36 snake species among 755 individuals found in the field and six records from scientific collections and literature, belonging to 25 genera and five families. The snake assemblage comparisons indicate that the Cerrado has its own identity regarding the snake composition. Although small (about 2,300 ha), the Estação Ecológica de Itirapina encompasses well preserved and representative Cerrado physiognomic forms, which harbors a rich and typical Cerrado snake fauna. The occurrence of some species only inside the reserve also indicates that the Estação Ecológica de Itirapina is of fundamental importance to the maintenance of Cerrado biodiversity.As taxocenoses de serpentes neotropicais apresenta m alta riqueza de espécies e estruturas complexas. O Cerrado é o segundo maior bioma do Brasil e foi incluído entre os 25 hotspots globais de biodiversidade. No sudeste do Brasil, as áreas remanescentes de Cerrado têm sofrido intensa destruição, e atualmente restam menos de 2% da vegetação natural de Cerrado no estado de São Paulo. Praticamente nenhum estudo detalhado sobre serpentes do Cerrado foi realizado nesta região. A região de Itirapina apresenta um dos últimos remanescentes bem preservados de cerrado aberto no estado de São Paulo. Nosso objetivo neste trabalho foi o estudo da história natural e composição das serpentes de Cerrado da região de Itirapina. Nós realizamos uma amostragem de campo extensiva combinando seis métodos de amostragem na Estação Ecológica de Itirapina e áreas alteradas de Cerrado nas proximidades (municípios de Itirapina e Brotas), em 101 viagens durante 43 meses, entre setembro de 1998 e março de 2002, o que correspondeu a 446 dias de amostragem de campo. Também coletamos dados adicionais a partir de espécimes de coleções científicas. Apresentamos dados sobre tamanho, abundância geral, uso do ambiente e substrato, atividade diária e sazonal, dieta, reprodução e defesa. Também comparamos a taxocenose de serpentes de Itirapina com nove taxocenoses de serpentes do Brasil, incluindo a Amazônia, Mata Atlântica, Cerrado e outras formações abertas. Registramos na região de Itirapina 36 espécies de serpentes entre 755 indivíduos encontrados no campo e seis registros de coleções científicas e literatura, pertencentes a 25 gêneros de cinco famílias. As comparações entre taxocenoses indicam que o Cerrado apresenta uma identidade própria em relação à composição de espécies de serpentes. Apesar de limitada a um pequeno fragmento (cerca de 2.300 ha), a Estação Ecológica de Itirapina apresenta fisionomias conservadas e representativas de Cerrado, que abrigam uma fauna de serpentes rica e típica do Cerrado. A ocorrência de algumas espécies apenas no interior da reserva também indica que a Estação Ecológica de Itirapina é de importância fundamental para a manutenção da biodiversidade do Cerrado.FAPESPConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Universidade de São Paulo (USP) - Instituto de Biociência

Potential impacts of changes in the Brazilian Forest Code on reptiles

Avaliamos os impactos potenciais sobre a fauna brasileira de répteis (721 espécies descritas até o momento), caso sejam adotadas mudanças propostas por um substitutivo do atual Código Florestal Brasileiro. A possibilidade de compensação ambiental (obrigação legal no caso de degradação de habitats naturais) em bacias ou microbacias distintas daquelas degradadas seria uma das modificações do código vigente que prejudicaria a manutenção da diversidade de répteis. Alguns gêneros de répteis são compostos por espécies que raramente co-ocorrem em uma mesma área. Assim, ações de conservação em escalas reduzidas, em unidades naturais como microbacias, seriam mais adequadas para representar a variação da composição de espécies entre áreas. O substitutivo prevê a exclusão de topos de montanhas como Área de Preservação Permanente (APP), bem como a redução da largura das matas marginais a cursos d´água (que também são APPs). Diversos répteis brasileiros estão restritos a áreas de altitude, ao passo que outros vivem somente ou principalmente em matas de galeria ou áreas ripárias. Assim, a perda de habitat nessas áreas deve tornar alguns répteis vulneráveis a extinção. A proposta também autoriza a recuperação de Reservas Legais (RL) usando espécies de plantas exóticas. Há evidências que muitos répteis brasileiros não conseguem sobreviver em ambientes alterados pelo homem, incluindo as florestas constituídas por espécies exóticas. A proposta também tornará possível compensar RL dentro de unidades de conservação. Entretanto, as unidades de conservação existentes não seriam suficientes para a manutenção da diversidade de répteis no Brasil (principalmente porque muitas espécies têm distribuição restrita). Se adotadas, as mudanças propostas ao Código Florestal Brasileiro terão fortes impactos sobre a fauna de répteis brasileira, um importante componente do patrimônio natural do país. Além disso, moléculas com potencial farmacêutico, presentes nos venenos de muitas espécies, poderão ser perdidas.We evaluate the potential impacts on Brazilian reptiles (721 species already described), if the proposed changes in the Brazilian Forest Code are approved. The possibility of environmental compensation (a legal obligation in case of disturbance of natural habitats) in basins or micro basins different from that in which the disturbance occurred would have harmful effects on reptile diversity. Some reptile genera include species that rarely co-occur in space. Thus, conservation action planning based on naturally smaller scales, such as micro basins, is most suitable to maintain species composition across large regions. The proposed changes also include the removal of mountaintops as Areas of Permanent Preservation (APP, areas which must be permanently protected, despite the fact that they are not part of a park), as well as a reduction in the width of gallery forests and protected riparian habitats (which are APPs). Many Brazilian reptiles are restricted to high elevation areas, whereas others dwell only or mostly in gallery forests and riparian areas. Thus, the habitat loss that would result from these two changes could make some reptiles vulnerable to extinction. The proposed changes also include allowing the restoration of the Legal Reserves (LR, the reserves of natural vegetation which landowners have to keep in private areas) using exotic plant species. There are evidences that many Brazilian reptiles are not able to persist in human-modified environments like forests composed of exotic trees. The proposed changes also allow the compensation of disturbances imposed on LR inside existing protected areas. However, existing protected areas are not sufficient for the maintenance of reptile diversity in Brazil (mainly because many species have restricted distributions). If approved, the proposed changes in the code will impose significant negative effects on the Brazilian reptile fauna, an important component of the country's natural heritage. Furthermore, unknown molecules with potential for pharmaceutical use could also be lost.CNPqCoordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)FAPES

UV and genotoxic stress induce ATR relocalization in mouse spermatocytes

During meiosis, phosphorylation of H2AX is one of the earliest cellular responses to the generation of DNA double-strand breaks (DSBs) by the SPO11 topoisomerase. ATM is the kinase which mediates the formation of phosphorylated H2AX (H2AX) meiotic foci, while ATR is the kinase which signals chromosome asynapsis at the level of the XY bivalent. To investigate the possible role of ATR also in DNA damage signalling in meiotic cells, we studied the effect of UV radiation and chemotherapy drugs on H2AX phosphorylation and ATR relocalization in mouse pachytene spermatocytes. Here, we report that UV, a single strand break DNA-damaging agent, induces ATR relocalization from the XY sex body to nuclear foci and intense H2AX phosphorylation. Other DNA damage proteins such as MDC1, NBS1 and 53BP1 showed a similar relocalization following UVA microirradiation of spermatocytes. We found that DNA damage induced by UV increased the intensity and the number of H2AX foci also in Atm null spermatocytes. Inhibition of RNA synthesis was found to induce the formation of H2AX foci, but it did not influence the DNA damage response to UV irradiation. Finally, exposure of spermatocytes to double strand break DNA-damaging agents such as cisplatin, bleomycin or etoposide also induced ATR relocalization and intense H2AX phosphorylation and led to anomalies in synaptonemal assembly. Our results demonstrate that DNA damage induced by genotoxic stress can activate ATR and influence meiotic chromatin remodelling through H2AX phosphorylation, likely as part of a response which normally ensures germ cell genomic integrity

Measurement of the thickness of the urethrovaginal space in women with or without vaginal orgasm

Introduction. The physiology and anatomy of female sexual function are poorly understood. The differences in sexual function among women may be partly attributed to anatomical factors. Aim. The purpose of this study was to use ultrasonography to evaluate the anatomical variability of the urethrovaginal space in women with and without vaginal orgasm. Methods. Twenty healthy, neurologically intact volunteers were recruited from a population of women who were a part of a previous published study. All women underwent a complete urodynamic evaluation and those with clinical and urodynamic urinary incontinence, idiopathic detrusor overactivity, or micturition disorders, as well as postmenopausal women and those with sexual dysfunction were excluded. The reported experience of vaginal orgasm was investigated. Main Outcome Measure. The urethrovaginal space thickness as measured by ultrasound was chosen as the indicator of urogenital anatomical variability. Designated evaluators carried out the measurements in a blinded fashion. Results. The urethrovaginal space and distal, middle, and proximal urethrovaginal segments were thinner in women without vaginal orgasm. A direct correlation between the presence of vaginal orgasm and the thickness of urethrovaginal space was found. Women with a thicker urethrovaginal space were more likely to experience vaginal orgasm (r = 0.884; P = 0.015). A direct and significant correlation between the thickness of each urethrovaginal segment and the presence of vaginal orgasm was found, with the best correlation observed for the distal segment (r = 0.863; P < 0.0001). Interobserver agreement between the designated evaluators was excellent (r = 0.87; P < 0.001). Conclusions. The measurement of the space within the anterior vaginal wall by ultrasonography is a simple tool to explore anatomical variability of the human clitoris-urethrovaginal complex, also known as the G-spot, which can be correlated to the ability to experience the vaginally activated orgasm

Popliteal artery entrapment syndrome: a differential diagnosis in lower limbs claudication: contribution of magnetic resonance imaging for diagnosis and evaluation

Universidade Federal de São Paulo (UNIFESP) Departamento de Diagnóstico por ImagemUNIFESPUNIFESP, Depto. de Diagnóstico por ImagemUNIFESPSciEL

Type V phosphodiesterase inhibitor treatments for erectile dysfunction increase testosterone levels.

OBJECTIVE Lack of sexual activity due to erectile dysfunction (ED) decreases testosterone (T) levels through a central effect on the hypothalamic-pituitary axis. In this paper we studied the effect of different type V phosphodiesterase (PDE5) inhibitor treatments for ED on the reversibility of this endocrine pattern. DESIGN Open-label, retrospective study. PATIENTS Seventy-four consecutive patients were treated on demand with sildenafil (Sild) (50 mg) and tadalafil (Tad) 20 mg. MEASUREMENTS The success in sexual intercourse was recorded and total (tT) and free testosterone (fT) levels were studied before and after 3 months of treatment. RESULTS Basal level of tT and fT were at the bottom of the normal range and LH levels were at the top of the high normal range. After treatments, this endocrine pattern was reversed in both groups. However, the T increase in Sild-treated patients was significantly lower than in those treated with Tad (4.7 +/- 2.7 vs. 5.1 +/- 0.9, P < 0.001). fT levels followed a directly proportional pattern, while the inverse was found when LH production was studied. The intercourse rate reflected this effect: in fact, the Sild group showed a 4.9 +/- 2.9/month full sexual intercourse rate while in the Tad group a significantly higher rate of sexual intercourse was found (6.9 +/- 4.6/month, P = 0.04). However, drug consumption was comparable between the groups (Sild 4.9 +/- 2.9 vs. Tad 4.4 +/- 2.8 pills/month, P = 0.72). CONCLUSIONS As it is unlikely that the two drugs have a different direct effect on the pituitary-testis axis, this effect is probably due to the higher frequency of full sexual intercourse in the Tad-treated group, because of the drug's longer half-life

SOHLH1 and SOHLH2 control Kit expression during postnatal male germ cell development

How Kit expression is regulated in the germline remains unknown. SOHLH1 and SOHLH2, two bHLH transcription factors specifically expressed in germ cells, are involved in spermatogonia and oocyte differentiation. In the male, deletion of each factor causes loss of Kit-expressing spermatogonia in the prepuberal testis. In the female, SOHLH1 and SOHLH2 ablations cause oocyte loss in the neonatal ovary. To investigate whether Kit expression is regulated by these two factors in male germ cells, we examined SOHLH1 and SOHLH2 expression during fetal and postnatal mouse development. We found a strong positive correlation between Kit and the two transcription factors only in postnatal spermatogonia. SOHLH2 was enriched in undifferentiated spermatogonia, whereas SOHLH1 expression was maximal at Kit-dependent stages. Expression of SOHLH1, but not SOHLH2, was increased in postnatal mitotic germ cells by treatment with all-trans retinoic acid. We found that E-box sequences within the Kit promoter and its first intron can be transactivated in transfection experiments overexpressing Sohlh1 or Sohlh2. Co-transfection of both factors showed a cooperative effect. EMSA experiments showed that SOHLH1 and SOHLH2 can independently and cooperatively bind an E-box-containing probe. In vivo co-immunoprecipitations indicated that the two proteins interact and overexpression of both factors increases endogenous Kit expression in embryonic stem cells. SOHLH1 was found by ChIP analysis to occupy an E-box-containing region within the Kit promoter in spermatogonia chromatin. Our results suggest that SOHLH1 and SOHLH2 directly stimulate Kit transcription in postnatal spermatogonia, thus activating the signaling involved in spermatogonia differentiation and spermatogenetic progression