Search results for "Sex organ"
showing 10 items of 57 documents
High variation in last male sperm precedence and genital morphology in the emerald damselfly, Lestes sponsa
2020
Abstract In organisms in which individuals mate multiply, knowledge of the proportion of offspring sired by the last male to mate (P2) under field conditions is important for a thorough understanding of how sexual selection works in nature. In many insect groups, pronounced intraspecific variation in P2 is commonplace. Interestingly, however, in stark contrast to these observations, compilation of P2 data in dragonflies and damselflies (Odonata) indicates that a high P2, seldom below 0.95, is a feature of this taxon. Here we used double digest restriction-site associated DNA sequencing to generate a panel of single nucleotide polymorphisms (SNPs) with which we could determine paternity and …
Males of the tortricid moth Amorbia cuneana (Walsingham, 1879) shed their genital spines inside the female during copulation
2018
Abstract The genitalia of most insect species are composed of several structures whose functions are poorly understood in many cases. The deciduous genital spines (deciduous cornuti, DC) found on the endophallus of many species of Lepidoptera are a clear example of this problem. We performed two experimental studies with the western avocado leafroller Amorbia cuneana (Tortricidae), aimed at answering some basic questions about the biology of DC. We found that the number of DC shows positive allometry with male forewing length, indicating that larger males have disproportionally more DC than smaller males. Males, with very few exceptions, shed virtually all their DC in their first copulation…
Calling behaviour of female Periplaneta americana: Behavioural analysis and identification of the pheromone source
1993
Abstract The site for the production of Periplanone B, one of the components of the female sex pheromone of Periplaneta americana , was localized in glands situated in the genital atrium, and we have called these structures atrial glands. While emitting the sex pheromone, females adopt a characteristic calling posture during which time the atrial glands are exposed. Behavioural assays of males utilizing pentane extracts of various female body parts revealed that atrial gland extracts are highly attractive, and induced more wing-raising behaviour, than any other female body part. GC-MS analyses support these results by revealing that Periplanone B is only present in the atrial glands. We est…
Sexual narcissism and its association with sexual and well-being outcomes
2020
Abstract Theories on narcissism are traditionally closely related to sexuality. Most research on the association between narcissism and sexual behavior, however, has focused on harmful/maladaptive outcomes. The aim of the present two studies was to examine the possible health-promoting influence of both global and sexual narcissism on sexual function and genital self-image. In Study 1, sexual narcissism was positively associated with sexual functioning in both women and men (N = 505, online-recruited German participants). In the women's sample, sexual narcissism was related to a positive genital self-image. The facet sexual skill was identified as the most important predictor for sexual fun…
Evolution of external female genital mutilation : why do males harm their mates?
2017
Sperm competition may select for male reproductive traits that influence female mating or oviposition rate. These traits may induce fitness costs to the female; however, they may be costly for the males as well as any decrease in female fitness also affects male fitness. Male adaptations to sperm competition manipulate females by altering not only female behaviour or physiology, but also female morphology. In orb-weaving spiders, mating may entail mutilation of external structures of the female genitalia, which prevents genital coupling with subsequent males. Here, we present a game theoretical model showing that external female genital mutilation is favoured even under relatively high cost…
Schistosoma haematobium Infection and CD4+ T-cell levels: A cross-sectional study of young South African women
2015
Schistosoma (S.) haematobium causes urogenital schistosomiasis and has been hypothesized to adversely impact HIV transmission and progression. On the other hand it has been hypothesized that HIV could influence the manifestations of schistosomiasis. In this cross-sectional study, we explored the association between urogenital S. haematobium infection and CD4 cell counts in 792 female high-school students from randomly selected schools in rural KwaZulu-Natal, South Africa. We also investigated the association between low CD4 cell counts in HIV positive women and the number of excreted schistosome eggs in urine. Sixteen percent were HIV positive and 31% had signs of urogenital schistosomiasis…
Oral human papillomavirus infection in women with cervical HPV infection: new data from an Italian cohort and a metanalysis of the literature.
2011
Summary A key issue in oral HPV infection is whether it can be associated with a genital HPV infection, or whether it can be considered as an independent event. This analysis evaluated the frequency and type-concordance of oral HPV infection in women with cervical HPV infection by means of: (i) a cross-sectional study on a sample (n = 98) of Italian women; and (ii) a literature-based metanalysis, including the experimental study the subject of this Paper and nine other published studies (n = 1017), which also examined the influence of oral sampling procedure (oral brushing vs oral rinse) and HIV status on oral HPV detection. The prevalence of oral HPV infection in the Italian study was 14.3…
Epstein-Barr virus is not detected in mucosal lichen planus
2018
Background Lichen planus (LP) is a chronic inflammatory, immunological, mucocutaneous disease can affect skin, genital and oral mucosa. Oral lichen planus (OLP) is the most common noninfectious, chronic inflammatory oral disease affecting 1-2% of the general adult population. World Health Organization (WHO) classifies OLP as a potentially malignant disorder. Epstein Barr virus or human herpesvirus-4, is a member of the herpes virus family and one of the most ubiquitous viruses known to human, infecting approximately 90% of the world’s adult population. The virus often infects B lymphocytes resulting in a wide spectrum of mucocutaneous and systemic diseases, ranging from mild lesions to aggr…
Epidemiology of desquamative gingivitis: evaluation of 125 patients and review of the literature
2009
Background Desquamative gingivitis (DG) is a descriptive term used to indicate epithelial desquamation, erythema, erosions, and/or vesiculobullous lesions of the gingiva. DG is commonly associated with several mucocutaneous disorders and systemic conditions that may carry a poor prognosis and high morbidity; however, there are no clear data concerning the frequency of these disease associations. Methods We investigated the epidemiologic features of DG in 125 patients and compared our findings with information from a literature review. Results In our series, 88% of patients with DG had one of the following three disorders: oral lichen planus (OLP), mucous membrane pemphigoid (MMP), or pem…
Sexual Function and Quality of Life in Adult Male Individuals with Exstrophy-Epispadias Complex—a Survey of the German CURE-Network
2017
Objective To investigate sexual function and quality of life (QoL) in adult male individuals with exstrophy-epispadias complex (EEC). Data from the German Network for Congenital Urorectal Malformations (CURE-Net) were used. Patients and Methods Fifty-one male participants (≥18 years) recruited by CURE-Net between 2009 and 2012 were re-contacted per mail and asked to fill out 4 questionnaires including International Index of Erectile Function (IIEF-5), Cologne Assessment of Erectile Dysfunction (KEED), the Short-Form 36 (SF-36), and one self-designed questionnaire about their medical history, current health status, and sexual experience. The SF-36 results were compared with general German po…