Conservation of magnetite biomineralization genes in all domains of life and implications for magnetic sensing.

Animals use geomagnetic fields for navigational cues, yet the sensory mechanism underlying magnetic perception remains poorly understood. One idea is that geomagnetic fields are physically transduced by magnetite crystals contained inside specialized receptor cells, but evidence for intracellular, biogenic magnetite in eukaryotes is scant. Certain bacteria produce magnetite crystals inside intracellular compartments, representing the most ancient form of biomineralization known and having evolved prior to emergence of the crown group of eukaryotes, raising the question of whether magnetite biomineralization in eukaryotes and prokaryotes might share a common evolutionary history. Here, we discover that salmonid olfactory epithelium contains magnetite crystals arranged in compact clusters and determine that genes differentially expressed in magnetic olfactory cells, contrasted to nonmagnetic olfactory cells, share ancestry with an ancient prokaryote magnetite biomineralization system, consistent with exaptation for use in eukaryotic magnetoreception. We also show that 11 prokaryote biomineralization genes are universally present among a diverse set of eukaryote taxa and that nine of those genes are present within the Asgard clade of archaea Lokiarchaeota that affiliates with eukaryotes in phylogenomic analysis. Consistent with deep homology, we present an evolutionary genetics hypothesis for magnetite formation among eukaryotes to motivate convergent approaches for examining magnetite-based magnetoreception, molecular origins of matrix-associated biomineralization processes, and eukaryogenesis.

Effects of Intranasal Oxytocin Administration on Sexual Functions in Healthy Women: A Laboratory Paradigm.

PURPOSE: The neuropeptide oxytocin (OXT) has a variety of physiological functions in maternal behavior and attachment including sexual behavior. Based on animal research and our previous human studies, we set out to investigate intranasal administration of OXT and hypothesized that OXT should be able to modulate sexual function in women. METHODS: In a double-blind, placebo-controlled, crossover laboratory setting, the acute effects of intranasal administered OXT (24 international units) on sexual drive, arousal, orgasm, and refractory aspects of sexual behavior were analyzed in 27 healthy females (mean age ± SD, 27.52 ± 8.04) together with physiological parameters using vaginal photoplethysmography. FINDINGS: Oxytocin administration showed no effect on subjective sexual parameters (eg, postorgasmic tension; P = 0.051). Physiological parameters (vaginal photoplethysmography amplitude and vaginal blood volume) showed a response pattern towards sexual arousal but were not affected by OXT. IMPLICATIONS: Using a well-established laboratory paradigm, we did not find that intranasal OXT influences female sexual parameters. Also, sexual drive and other functions were not affected by OXT. These findings indicate that OXT is not able to significantly increase subjective and objective parameters of sexual function in a setting with high internal validity; however, this might be different in a more naturalistic setting.

Reduction of Risk Factors for Pedophilic Sexual Offending.

INTRODUCTION: Exploratory analysis of characteristics and reduction of risk factors for child sexual abuse (CSA) in a sample treated in the Prevention Projects Dunkelfeld Hannover and Regensburg. AIM: To evaluate a treatment program aimed at reducing dynamic risk factors (DRF) for CSA. METHODS: Using a psychometric test battery based on self-report questionnaires, intergroup analysis between treatment group (TG, n = 35), treatment refusers (TR, n = 51), and drop-out group (DO, n = 14) was conducted with pretreatment data. Intragroup analysis compared data of TG from pre- and posttreatment. The test battery included sociodemographic and sociosexual data, as well as questionnaires measuring DRF. MAIN OUTCOME MEASURE: This study investigated effects of treatment on pedophilic men who are at risk for offending and observed reductions in important risk factors for CSA. RESULTS: TG, TR (consisting of persons who were offered but refused therapy), and DO did not differ regarding sociodemographic and sociosexual variables before therapy. There were no significant differences in education, relationship status, living solitarily, and being a father/stepfather. TR and DO lived farther away from treatment site than TG. In the TG, a reduction in offense-supportive attitudes, coping self-efficacy deficits, and child identification were revealed at second assessment. In TG no participants started the consumption of child abuse content during the course of the study. CLINICAL IMPLICATIONS: Future treatment concepts should focus on the reduction of empirically relevant risk factors for child sexual offending. STRENGTH & LIMITATIONS: The present article is the first that compares TG to TR and DO before assessment regarding DRF and sociosexual variables. Moreover, it is only the second study that investigated treatment effects on a population of pedophilic men who are at risk for offending. These preliminary findings are limited by moderate group size and a missing control group. CONCLUSION: A reduction in some but not all assessed risk factors for sexual offending against minors could be seen within the time frame of therapy. Findings are in line with results from a previous evaluation study. Engel J, Körner M, Schuhman P. Reduction of risk factors for pedophilic sexual offending. J Sex Med 2018;15:1629-1637.

Lack of Increase in Sexual Drive and Function After Dopaminergic Stimulation in Women.

Human and animal data indicate that the dopaminergic system plays a crucial role in sexual drive and function. Using a double-blind, placebo-controlled crossover design, this prototype study investigated the effect of the D2 dopamine agonist cabergoline on sexual parameters in 13 healthy women. Cardiovascular and genital parameters were monitored continuously. Sexual drive and function were measured using self-report sexual experience scales. In contrast to previous theories and assumptions, we found that cabergoline did not alter objective and subjective sexual parameters in healthy women. This finding suggests that there may be sex differences in the influence of the dopaminergic system on human sexual functioning.

Placebo and Nocebo Effects in Sexual Medicine: An Experimental Approach.

Few studies have investigated placebo and nocebo effects in a human sexuality context. Studying placebo and nocebo responses in this context may provide insight into their potential to modulate sexual drive and function. To examine such effects in sexual medicine, 48 healthy, male heterosexual participants were divided into four groups. Each group received instruction to expect stimulating effects, no effect, or an inhibitory effect on sexual functions. Only one group received the dopamine agonist cabergoline; all other groups received placebo or nocebo. Modulations in sexual experience were examined through an established experimental paradigm of sexual arousal and masturbation-induced orgasm during erotic film sequences with instruction to induce placebo or nocebo effects. Endocrine data, appetitive, consummatory, and refractory sexual behavior parameters were assessed using the Arizona Sexual Experience Scale (ASEX) and the Acute Sexual Experience Scale (ASES). Results showed increased levels of sexual function after administration of cabergoline with significant effects for several parameters. Placebo effects were induced only to a small degree. No negative effects on sexual parameters in the nocebo condition were noted. This paradigm could induce only small placebo and nocebo effects. This supports the view that healthy male sexual function seems relatively resistant to negative external influences.

Differential effects of intranasal oxytocin on sexual experiences and partner interactions in couples.

Knowledge about the effects of the neuropeptide oxytocin (OXT) on human sexual behaviors and partner interactions remains limited. Based on our previous studies, we hypothesize that OXT should be able to positively influence parameters of sexual function and couple interactions. Employing a naturalistic setting involving 29 healthy heterosexual couples (n=58 participants), we analyzed the acute effects of intranasally administered OXT (24IU) on sexual drive, arousal, orgasm and refractory aspects of sexual behavior together with partner interactions. Data were assessed by psychometric instruments (Acute Sexual Experiences Scale, Arizona Sexual Experience Scale) as well as biomarkers, such as cortisol, α-amylase and heart rate. Intranasal OXT administration did not alter "classical" parameters of sexual function, such as sexual drive, arousal or penile erection and lubrication. However, analysis of variance and a hierarchical linear model (HLM) revealed specific effects related to the orgasmic/post-orgasmic interval as well as parameters of partner interactions. According to HLM analysis, OXT increased the intensity of orgasm, contentment after sexual intercourse and the effect of study participation. According to ANOVA analysis, these effects were more pronounced in men. Men additionally indicated higher levels of sexual satiety after sexual intercourse with OXT administration. Women felt more relaxed and subgroups indicated better abilities to share sexual desires or to empathize with their partners. The effect sizes were small to moderate. Biomarkers indicated moderate psychophysiological activation but were not affected by OXT, gender or method of contraception. Using a naturalistic setting, intranasal OXT administration in couples exerted differential effects on parameters of sexual function and partner interactions. These results warrant further investigations, including subjects with sexual and relationship problems.

The real-life perception of efficacy, attitude, satisfaction and safety of vardenafil therapy (REPEAT): a prospective, non-interventional, observational study.

This study assessed the improvement in relationship quality, effectiveness and safety associated with vardenafil for the treatment of erectile dysfunction (ED). The study was conducted in 1433 centres across 21 countries and comprised a baseline patient visit and up to four follow-up visits during an observational period of 1 year. Relationship quality, happiness, satisfaction with vardenafil treatment, and safety and tolerability were assessed by physician interviews and patient and partner questionnaires. Overall, 7496 patients were enrolled in the study, of which 7430 were included in the safety analyses and 6470 in the effectiveness analyses. Relationship quality, assessed by a relationship questionnaire (partnerschaftsfragebogen [PFB]), was improved at last observation carried forward, compared with baseline, in both patients and partners and satisfaction with the effectiveness of vardenafil treatment was high. Vardenafil was well tolerated and adverse events were consistent with the known safety profile of phosphodiesterase type 5 inhibitors. These results confirm the well-established effectiveness and safety profiles of vardenafil. This study is the first to demonstrate improvements in relationship quality following vardenafil therapy, in both patients and partners, using the PFB questionnaire.

Hypersexual behavior in an online sample of males: associations with personal distress and functional impairment.

INTRODUCTION: The population of individuals reporting hypersexual behavior is heterogeneous. Prior research has implicated the importance of personal distress and functional impairment, as both may serve as indicators of problem severity and relevance. Still, little is known about associations with distress and impairment following hypersexuality. AIM: The purpose of this study was to investigate personal distress and functional impairment in a community sample of male self-identified "sex addicts" and to explore the associations with related variables. METHODS: Three hundred forty-nine men completed an online survey that included questions about personal distress, functional impairment, motivation for behavior change, type of hypersexual behaviors, time spent on sexual behavior, and progression of sexual urges. The survey included the Sexual Addiction Screening Test-Revised (SAST-R) core. MAIN OUTCOME MEASURE: Specific survey questions about personal distress and functional impairment in six life areas were used to assess these variables. Chi-square and P-values were calculated to explore the interrelations among them. RESULTS: There were 75.3% (N = 253) who reported feeling distressed due to hypersexual behavior. Functional impairment in at least one life area was specified by 77.4% (N = 270), and most participants (56.2%) reported impairment regarding partner relationships. Personal distress and functional impairment in three areas were associated with a strong motivation for behavior change. Distress was associated with online pornography use, masturbation, and/or sexual contact with changing partners. The progression of sexual urges was related to distress, while time spent on sexual behavior was not. There were 92.9% of the distressed participants who scored above the SAST-R core scale cut-off, but also 59.0% of the participants with little or no distress scored in this range. CONCLUSIONS: Results underline the particular role of problems in social or intimate relationships in association with hypersexuality. Clustering individuals with regard to their specific sexual behavior and impairment pattern seems to be promising for further research.

Personality dimensions of compulsive sexual behavior in the Sex@Brain study.

Background and aims: Hypersexual disorder is characterized by recurrent and intense sexual fantasies, sexual urges, or sexual behaviors that can lead to clinically relevant levels of distress and adverse consequences for affected individuals. Earlier research has established a connection between sexual phenomena, such as compulsive sexual behavior, and personality features. The aim of the present study was to gain further insights into the associations of personality maladjustment and HD. Methods: The present study applied the dimensional approach of personality maladjustment presented in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) to connect compulsive sexual behavior to personality maladjustment. We investigated 47 men suffering from HD (age: M = 36.51, SD = 11.47) and 38 matched men without HD (age: M = 37.92, SD = 12.33) regarding personality maladjustment using a 100-item version of the Personality Inventory for DSM-5 (PID-5-BF). Results: The men with HD showed higher levels of personality maladjustment regarding all PID-5-BF domains (negative affect, detachment, psychoticism, antagonism, and disinhibition) and significantly differentiated from men without HD in the level of subordinate facets. However, no domain of personality differentiated significantly between groups using a binary stepwise logistic regression analysis. Discussion and conclusions: In sum, the findings of the study underline the extent of personality maladjustment in men with HD. Interpersonal difficulties which men with HD frequently experience can contribute to clinically relevant levels of distress and adverse consequences reported by affected individuals.

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 humans.

Individual and dyadic barriers to a pharmacotherapeutic treatment of hypoactive sexual desire disorders: results and implications from a small-scale study with bupropion.

This article describes the results of an independent small-scale trial with the centrally acting agent bupropion for female hypoactive sexual desire disorder. The main goals were to gain insight into the intrapsychic and interpersonal barriers to improvement associated with the pharmacological treatment of this common disorder. Eligible subjects entered a 2-week run-in period and a 4-week placebo phase, followed by a 20-week treatment phase. In addition to semi-structured clinical interviews and a set of standardized questionnaires, we used 2 self-developed questionnaires, addressing the period between visits and the week preceding each visit. Participants were 16 women who entered the placebo phase and 10 who completed the medication period. Analyses of pre-post scores and of the questionnaire addressing the time between visits yielded no significant changes. The questionnaire focusing on the week preceding each visit indicated improvements in sexual desire, arousability, and orgasmic ease after Week 8. In the clinical interviews, half of the women reported subjective improvements of sexual desire and arousability that could not be transferred to the sexual relationship as a result of individual and dyadic barriers. Overall, a centrally acting agent such as bupropion may be a viable option for female sexual dysfunction, but it seems mandatory to embed it in a psychotherapeutic approach.

Sigmund Freud and his impact on our understanding of male sexual dysfunction.

INTRODUCTION: Sigmund Freud was one of the most influential thinkers and theorists of the 20th century. His groundbreaking work laid the foundation to many concepts and theories relevant to modern sexual medicine. AIM: To evaluate Freud's approaches to the understanding of male sexual dysfunction both in their historical context and with respect to their significance for contemporary research and therapy of sexual problems. METHODS: After a brief biographical sketch, two of Freud's writings, the widely acclaimed "Three Essays on the Theory of Sexuality" from 1905, and a short article entitled "The Most Prevalent Form of Degradation in Erotic Life" from 1912, were analyzed, especially for their relevance to present treatment concepts of male sexual dysfunction. RESULTS: In Freud's clinical practice "psychical impotence" was a highly prevalent complaint. In his view, this dysfunction was caused by an inhibition due to an unresolved neurotic fixation leading to an arrest of the libidinal development. The result is a splitting of the tender and the sensual dimension of sexuality, most notably in the so-called madonna-whore complex. The degree of this dissociation (total or partial) determines the severity of the ensuing sexual dysfunction. In Freud's rather pessimistic view, the erotic life of civilized people tends to be characterized by some degree of this condition. CONCLUSIONS: While some of Freud's theories are obsolete today, many parts of his work appear to be astonishingly modern, even in the light of current neurobiological research and recent models of sexual dysfunction. Above all, Freud was an extremely gifted observer of human behavior who shows us that in many cases, sexual dysfunctions are no isolated phenomena, but have their roots in biographically based intrapsychic or interpersonal conflicts.

Determinants of sexual satisfaction in a sample of German women.

INTRODUCTION: The literature provides little information about the meaning of sexual satisfaction in women despite debates on new concepts of female sexual experience and on modifications in the classification systems of female sexual dysfunction. Often, not even a differentiation is made between satisfaction with one's sex life or sexual relationship in general and sexual satisfaction related to a specific sexual activity. AIM: To differentiate between satisfaction with sex life in general and sexual satisfaction from sexual intercourse, petting, or masturbation. To gain a deeper understanding of the meaning and experience of sexual satisfaction derived from these specific sexual activities. METHODS: A self-administered questionnaire was completed by 102 German women of different age groups (median age group: 31-35) and education levels. MAIN OUTCOME MEASURES: A multidimensional questionnaire addressing the subjective feelings that constitute sexual satisfaction in women. RESULTS: The analysis of sexual satisfaction from sexual intercourse yielded two dimensions: (i) feeling close to one's partner; and (ii) positive bodily and emotional experiences. Regarding satisfaction with one's sex life in general, 70% of the variance could be explained by sexual satisfaction through sexual intercourse and frequency of sexual intercourse. Sexual satisfaction and orgasm frequency proved to be interdependent but not identical. CONCLUSIONS: As a contribution to a better understanding of the complex nature of female sexual satisfaction, our results indicate that sexual intercourse is a far more important activity and source of satisfaction in female sexual life than petting or masturbation.

Cell-surface interactions involving immobilized magnetite nanoparticles on flat magnetic substrates.

A new method to affect cells by cell-surface interaction is introduced. Biocompatible magnetic nanobeads are deposited onto a biocompatible magnetic thin layer. The particles are composed of small magnetite crystals embedded in a matrix which can be functionalized by different molecules, proteins or growth factors. The magnetic interaction between surface and beads prevents endocytosis if the setup is utilized for cell culturing. The force acting between particles and magnetic layer is calculated by a magnetostatic approach. Biocompatibility is ensured by using garnet layers which turned out to be nontoxic and stable under culturing conditions. The garnet thin films exhibit spatially and temporally variable magnetic domain configurations in changing external magnetic fields and depending on their thermal pretreatment. Several patterns and bead deposition methods as well as the cell-surface interactions were analyzed. In some cases the cells show directed growth. Theoretical considerations explaining particular cell behavior on this magnetic material involve calculations of cell growth on elastic substrates and bending of cell membranes.

State of the Art Treatment Options for Actual and Potential Sexual Offenders and New Prevention Strategies.

Sexual violence is a significant and devastating issue for men and women throughout the world. Its consequences are not only disastrous for victims of sexual violence but are also extremely costly (estimated cost of $41,000 per rape) for society. Successful treatment of sexual offenders is therefore an important goal for society as well as for victims and offenders themselves. Over the years, multiple treatment approaches for sex offenders have been developed. Treatment programs range from the risk-need-responsivity (RNR) model, which focuses on providing tailored treatment for high-risk and low-risk offenders, to psychodynamic models. This article presents an overview for clinicians of state-of-the-art offender treatment, describing the most common treatment approaches, in particular the RNR model, cognitive-behavioral programs (relapse prevention programs, sexual offender treatment programs), psychodynamic approaches (transference-focused psychotherapy, mentalization-based therapy), the Good Lives Model, as well as pharmacological options. In addition, it provides an evaluation of the various treatment programs. However, given the fact that most acts of sexual violence will never be reported to the police, the question arises if treating convicted perpetrators is enough. Do we need rather-in terms of preventive work-a program for potential sexual offenders and men with delinquent sexual fantasies? Given the prevalence of sexual violence and its impact on victims, society, and the medical community, it would be remiss not to try to reach potential/unconvicted perpetrators. This article offers novel ideas and a project the goal of which is to prevent sexual offenses against women by introducing the "I CAN CHANGE" program from Hannover Medical School.

Hypersexual behavior in a large online sample: Individual characteristics and signs of coercive sexual behavior.

BACKGROUND AND AIMS: Despite the high prevalence of perceived problems relating to symptoms of hypersexual disorder (HD), important aspects remain underinvestigated. This study examines symptoms of depression, symptoms of problematic cybersex, and coercive sexual behavior in a large online sample from a German-speaking population. METHODS: In an online survey, N = 1,194 (n = 564 women) participated in this study and completed measures including self-report questionnaires to assess depressive symptoms (PHQ-9), HD (HBI-19), symptoms of problematic cybersex (s-IATsex), as well as questions characterizing participants sexually, including fantasies and actual sexual coercive behaviors. RESULTS: Men reported increased levels of HD symptom severity, pornography consumption, masturbation, and partnered sexual activity. Moreover, 59% of men and 18% of women reported fantasies of sexual coercion, whereas 21% of men and 4% of women reported acts of sexual coercion. Moderated regression analyses showed that symptoms of depression as well as sexual coercive fantasies and behaviors were associated with levels of HD symptom severity. Problematic cybersex, total sexual outlet (TSO), pornography consumption, and number of sexual partners were also associated with HD symptom severity. Interaction effects indicated that, in women, the connection of TSO as well as pornography was more strongly associated with levels of HD symptom severity than in men. CONCLUSIONS: This survey indicated that levels of HD symptom severity are often associated with severe intra- and interpersonal difficulties. Furthermore, the amount of sexual activity seems to be more strongly connected to levels of HD symptom severity in women than in men.

Same Same but Different: A Clinical Characterization of Men with Hypersexual Disorder in the Sex@Brain Study.

Problems arising from hypersexual behavior are often seen in clinical settings. We aimed to extend the knowledge about the clinical characteristics of individuals with hypersexual disorder (HD). A group of people who fulfilled the proposed diagnostic criteria for HD (men with HD, n = 50) was compared to a group of healthy controls (n = 40). We investigated differences in sociodemographic, neurodevelopmental, and family factors based on self-report questionnaires and clinical interviews. Men with HD reported elevated rates of sexual activity, paraphilias, consumption of child abusive images, and sexual coercive behavior compared to healthy controls. Moreover, rates of affective disorders, attachment difficulties, impulsivity, and dysfunctional emotion regulation strategies were higher in men with HD. Men with HD seem to have experienced various forms of adverse childhood experiences, but there were no further differences in sociodemographic, neurodevelopmental factors, and family factors. Regression analyses indicated that attachment-related avoidance and early onset of masturbation differentiated between men with HD and healthy controls. In conclusion, men with HD appear to have the same neurodevelopment, intelligence levels, sociodemographic background, and family factors compared to healthy controls, but they report different and adverse experiences in childhood, problematic sexual behavior, and psychological difficulties.

Low-force spectroscopy on graphene membranes by scanning tunneling microscopy.

Two-dimensional atomically flat sheets with a high mechanical flexibility are very attractive as ultrathin membranes but are also inherently challenging for microscopic investigations. We report on a method using Scanning Tunneling Microscopy (STM) under ultra-high vacuum conditions for non-indenting low-force spectroscopy on micrometer-sized freestanding graphene membranes. The method is based on applying quasi-static voltage ramps with active feedback at low tunneling currents and ultimately relies on the attractive electrostatic force between the tip and the membrane. As a result a bulge-test scenario can be established. The convenience and simplicity of the method relies on the fact that the loading force and the membrane deflection detection are both provided simultaneously by the STM. This permits the continuous measurement of the stress-strain relation. Electrostatic forces applied are typically below 1 nN and the membrane deflection is detected at sub-nanometer resolution. Experiments on single-layer graphene membranes with a strain of 0.1% reveal a two-dimensional elastic modulus E2D = 220 N m-1.