Prolactin secretory rhythm in women: immediate and long-term alterations after sexual contact

BACKGROUND Prolactin (PRL) is one of the most versatile hormones in the mammalian body, affecting reproductive, sexual and other functions. In rats, mating or vaginocervical stimulation activates a characteristic PRL secretory pattern for several days, which is essential for successful reproduction. Although the underlying mechanisms appear to be different, PRL is also crucial for human fertility. We have detected a PRL increase in women induced by sexual intercourse. Extending these findings, the current study aimed at analyzing the PRL secretory rhythm after sexual contact, in order to elucidate whether human females also show long-term alterations of the PRL secretory pattern. METHODS In a pilot study, serial blood samples were taken from women (n= 7) in mid-cycle to assess changes in PRL secretory rhythm induced by sexual intercourse, during a period of 32 h. RESULTS Compared with control condition, sexual intercourse with orgasm induced not only the well-established immediate PRL increase of ∼300% but also an additional PRL elevation around noon of the next day (P< 0.05). These fluctuations were measured on top of the regular circadian rhythm of PRL, manifested as a surge early in the morning. CONCLUSIONS We are able to demonstrate a long-term change in the PRL secretory rhythm after sexual intercourse with orgasm in females, suggesting memory effects. We hypothesize that the additionally secreted PRL could be beneficial for decidualization and implantation. Further studies with more participants are required to investigate in detail the implications of such effects on reproductive success in human

Na superfície da areia o movimento efêmero do desenho

O texto aborda o desenho na superfície da areia observados em percursos estéticos realizados no Pontal da Daniela situado em Florianópolis, Santa Catarina. Em práticas artísticas pela orla da praia, registrou-se imagens fotográficas dos rastros de pequenas espécies, habitantes deste lugar, que configuravam desenhos singulares e espontâneos sem interferências humanas. No processo da escrita, entre articulações filosóficas e poéticas, apresentam-se essas imagens em atravessamentos com as noções de invisibilidade e visibilidade, presentes na linguagem do desenho em Jacques Derrida, e com a configuração de uma quase virtualidade em modos de ver de David Lapoujade. Finalmente, a configuração do trabalho propõe trazer os esboços que se desenham e se inscrevem no território arenoso, intensificando suas existências mínimas

Escrever com o que fica e escapa em pesquisas

This text tries to think with what escapes a research and remains in the paths of life, both teaching and artistic, of two researchers. How to make visible what remains suspended along the way, collected or hidden, which was left aside in the works carried out? It was the question that spurred the writing of these authors in research processes in the areas of art and education. These remnants or leftovers of research made possible a writing that rejects hierarchical and dominant attacks. It proposes inventions of new problems in sensible compositions, entangled with different practices in a minor key (traces in photos, embroidery, and other things). What was intended was the tracking of sleeping pictures and points in the cabinets and drawers, left on the sidelines, in research carried out by the researchers in the field of visual arts.Este texto ensaya el acto de pensar con lo que escapa a una investigación y permanece en los caminos de la vida, tanto docente como artística, de dos investigadoras. ¿Cómo visibilizar lo que queda suspendido a lo largo del recorrido, recogido u oculto, que, en cierto modo, fue dejado de lado en los trabajos realizados? Fue la pregunta que impulsó la escritura de los dos autores en los procesos de investigación en las áreas del arte y la educación. Estos remanentes o sobras de investigación posibilitaron una escritura que rechaza los ataques jerárquicos y dominantes, pues propone invenciones de nuevos problemas en composiciones sensibles, enredadas en menor medida con prácticas diversas (huellas en fotografías, bordados, etc.). Lo que se pretendía era el calco de imágenes dormidas y apuntes en los armarios y cajones, dejados al margen, en la investigación emprendida por los dos investigadores en el campo de las artes visuales.Este texto ensaia o pensar com o que escapa de uma pesquisa e permanece nos caminhos da vida, docente e artística, de duas pesquisadoras. Como visibilizar o que fica em suspenso pelo percurso, recolhido ou escondido, que, de certo modo, ficou deixado de lado nos trabalhos realizados? Foi a pergunta que impulsionou a escrita das autoras em processos de investigação nas áreas de arte e da educação. Esses restos ou sobras de pesquisas possibilitaram uma escrita que recusa investidas hierárquicas e dominantes, propondo invenções de novos problemas em composições sensíveis, emaranhadas a diversas práticas em um tom menor (rastros em fotos, bordados etc.). O que se pretendeu foi o rastreio de imagens e notas adormecidas nos guardados e gavetas, deixados à margem, em pesquisas empreendidas pelas pesquisadoras na área de artes visuais

Na superfície da areia o movimento efêmero do desenho

O texto aborda o desenho na superfície da areia observados em percursos estéticos realizados no Pontal da Daniela situado em Florianópolis, Santa Catarina. Em práticas artísticas pela orla da praia, registrou-se imagens fotográficas dos rastros de pequenas espécies, habitantes deste lugar, que configuravam desenhos singulares e espontâneos sem interferências humanas. No processo da escrita, entre articulações filosóficas e poéticas, apresentam-se essas imagens em atravessamentos com as noções de invisibilidade e visibilidade, presentes na linguagem do desenho em Jacques Derrida, e com a configuração de uma quase virtualidade em modos de ver de David Lapoujade. Finalmente, a configuração do trabalho propõe trazer os esboços que se desenham e se inscrevem no território arenoso, intensificando suas existências mínimas.</jats:p

The quality of sexual experience in women correlates with post-orgasmic prolactin surges: results from an experimental prototype study

INTRODUCTION: Sexual intercourse, orgasm, and sexual satisfaction are associated with well-being and improved quality of life. The pituitary hormone prolactin (PRL) may have an important role in regulating (and thus indexing) sexual satiety and satisfaction. AIM: Physiological indices to quantify the quality and resulting satisfaction from female orgasm would be valuable. Therefore we aim to validate associations of orgasm-induced PRL surges with women's orgasm quality and subsequent sexual satisfaction. METHODS: In a prospective study, with a pre-post, single-blinded, cross-over design in a naturalistic field setting, we analyzed the correlation of women's post-orgasmic serum PRL surges following sexual intercourse with women's perceived quality of orgasm and resulting sexual satisfaction, as measured by a questionnaire. MAIN OUTCOME MEASURES: PRL levels prior to and following penile-vaginal intercourse with and without orgasm, and scores from the Acute Sexual Experience Scale (ASES) on quality of orgasm and sexual satisfaction. RESULTS: An analysis of variance of the blood samples in nine women indicated large magnitude, significant effects of intercourse orgasm on PRL levels (P = 0.004, eta squared = 0.78), as well as an interaction with the effect of multiple orgasms (P = 0.008, eta squared = 0.80). PRL post/pre ratios and arithmetic difference correlated strongly with orgasm quality (r = 0.85, P = 0.016, and r = 0.69, P = 0.08) and sexual satisfaction (r = 0.75, P = 0.05 and r = 0.77, P = 0.045). CONCLUSION: Women's intercourse orgasm induced PRL surges are strongly related to the quality of orgasm and subsequent sexual satisfaction. This implies that post-orgasmic PRL surges are an objective index of orgasm and orgasm quality. PRL might be used in future studies on basic research as well as a treatment target in sexual disorders in women

Titanium Implant Characteristics After Implantoplasty: An In Vitro Study on Two Different Kinds of Instrumentation

PURPOSE To assess surface characteristics and implant stability after implantoplasty performed by two different instrument sequences regarding material loss, surface roughness, and fracture load resistance. Additionally, operators' subjective experience during instrumentation and the damage to neighboring teeth were evaluated. MATERIALS AND METHODS Titanium implants were placed in the position of both first maxillary molars in models exposing 6 mm of their surface. Implantoplasty was performed in phantom heads: Exposed surfaces were instrumented with diamonds and Arkansas stones or abrasive stones and silicone polishers. Operators reported on abrasion, gloss, effectiveness, and tactility using a visual analog scale (VAS). Residual wall thickness of implants was measured on radiographs, material abrasion using three-dimensional (3D) scans, and surface roughness by contact profilometry. Maximum bending moments were measured. RESULTS Residual thickness and weight loss were comparable after both treatments (0.3 ± 0.1 and 0.25 ± 0.07 mm and 0.22 ± 0.01 g, and 0.03 ± 0.01 mm and 0.02 ± 0.01 g, respectively, P > .05). Mean surface roughness was lower (P = .0001) for the group with the silicone polishers (0.4 ± 0.2 μm) compared with the group employing diamonds (0.8 ± 0.1 μm). Maximum bending moments showed neither intergroup differences nor stability loss compared with untreated implants. The stone-and-silicone polisher group showed less abrasion (4.6 ± 2.2) and higher gloss values (8.1 ± 1.4) than the diamond-and-Arkansas group (3.1 ± 1.3 and 4.1 ± 2.1, respectively). Superficial tooth injuries at proximal neighbor teeth were common (73% and 80%). CONCLUSION Implantoplasty did not weaken implant stability. The use of silicone polishers revealed lower surface roughness. Regarding surface smoothness, the instrumentation sequence employing silicon carbide and Arkansas stones followed by silicone polishers seems to be superior to the combination of diamond and Arkansas stones

Contribution of Specific Residues of the beta-Solenoid Fold to HET-s Prion Function, Amyloid Structure and Stability

The [Het-s] prion of the fungus Podospora anserina represents a good model system for studying the structure-function relationship in amyloid proteins because a high resolution solid-state NMR structure of the amyloid prion form of the HET-s prion forming domain (PFD) is available. The HET-s PFD adopts a specific β-solenoid fold with two rungs of β-strands delimiting a triangular hydrophobic core. A C-terminal loop folds back onto the rigid core region and forms a more dynamic semi-hydrophobic pocket extending the hydrophobic core. Herein, an alanine scanning mutagenesis of the HET-s PFD was conducted. Different structural elements identified in the prion fold such as the triangular hydrophobic core, the salt bridges, the asparagines ladders and the C-terminal loop were altered and the effect of these mutations on prion function, fibril structure and stability was assayed. Prion activity and structure were found to be very robust; only a few key mutations were able to corrupt structure and function. While some mutations strongly destabilize the fold, many substitutions in fact increase stability of the fold. This increase in structural stability did not influence prion formation propensity in vivo. However, if an Ala replacement did alter the structure of the core or did influence the shape of the denaturation curve, the corresponding variant showed a decreased prion efficacy. It is also the finding that in addition to the structural elements of the rigid core region, the aromatic residues in the C-terminal semi-hydrophobic pocket are critical for prion propagation. Mutations in the latter region either positively or negatively affected prion formation. We thus identify a region that modulates prion formation although it is not part of the rigid cross-β core, an observation that might be relevant to other amyloid models

GuHCl unfolding measurements of HET-s(218–289) amyloid fibrils and Ala variants thereof.

<p>The GuHCl denaturation curve of amyloid fibrils of HET-s(218–289) and Ala variants (as indicated) were measured by the OD₅₀₀ (y-axis) at various GuHCl concentration (x-axis) after incubation in the corresponding GuHCl buffers for one day. The change of the OD₅₀₀ value is indicative of the loss of large aggregated protein species. Three samples each were incubated and the individual measurements are highlighted by asterisks, by small dots, or by open circles, respectively. Individual successful fits following the concept by Santoro and Bolen to study protein folding and unfolding <a href="http://www.plospathogens.org/article/info:doi/10.1371/journal.ppat.1004158#ppat.1004158-Santoro1" target="_blank">[61]</a> are shown by black lines and the calculated change in Gibbs energy (ΔG) with its standard deviation from the three measurements are listed in <a href="http://www.plospathogens.org/article/info:doi/10.1371/journal.ppat.1004158#ppat-1004158-t003" target="_blank">Table 3</a>.</p