Contexts of care for people with differences of sex development: Diversity is still missing in the laboratory routine.

The 2006 Chicago consensus statement of management of disorders/difference of sex development (DSD) has achieved advantages in clinical care and diagnosis for patients and families affect by DSD. This article provides a brief overview of contexts of care for physicians, and points out specific challenges in clinical practice that have arisen from the transformations of the sex/gender system in recent years. We focus on the impact of diagnosis and laboratory measurements. Both laboratory measurements and hormonal therapies still depend on the binary system. One problem is the lack of reference intervals for the different forms of DSD, which means that diversity is often neglected. In the following, we will give a brief insight into this complex topic.

Diagnosis of DSD in Children-Development of New Tools for a Structured Diagnostic and Information Management Program within the Empower-DSD Study.

BACKGROUND: Current recommendations define a structured diagnostic process, transparent information, and psychosocial support by a specialized, multi-professional team as central in the care for children and adolescents with genital variations and a suspected difference of sex development (DSD). The active involvement of the child and their parents in shared decision-making should result in an individualized care plan. So far, this process has not been standardized. METHODS: Within the Empower-DSD study, a team of professionals and representatives of patient advocacy groups developed a new diagnostic and information management program based on current recommendations and existing patient information. RESULTS: The information management defines and standardizes generic care elements for the first weeks after a suspected DSD diagnosis. Three different tools were developed: a guideline for the specialized multiprofessional team, a personal health record and information kit for the child with DSD and their family, and a booklet for medical staff not specialized in DSD. CONCLUSIONS: The new information management offers guidance for patients and professionals during the first weeks after a DSD diagnosis is suspected. The developed tools' evaluation will provide further insight into the diagnostic and information-sharing process as well as into all of the involved stakeholders' needs.

Development and evaluation of a patient education programme for children, adolescents, and young adults with differences of sex development (DSD) and their parents: study protocol of Empower-DSD.

BACKGROUND: Differences in sexual development (DSD) are rare diseases, which affect the chromosomal, anatomical or gonadal sex differentiation. Although patient education is recommended as essential in a holistic care approach, standardised programmes are still lacking. The present protocol describes the aims, study design and methods of the Empower-DSD project, which developed an age-adapted multidisciplinary education programme to improve the diagnosis-specific knowledge, skills and empowerment of patients and their parents. METHODS: The new patient education programme was developed for children, adolescents and young adults with congenital adrenal hyperplasia, Turner syndrome, Klinefelter syndrome or XX-/or XY-DSD and their parents. The quantitative and qualitative evaluation methods include standardised questionnaires, semi-structured interviews, and participatory observation. The main outcomes (assessed three and six months after the end of the programme) are health-related quality of life, disease burden, coping, and diagnosis-specific knowledge. The qualitative evaluation examines individual expectations and perceptions of the programme. The results of the quantitative and qualitative evaluation will be triangulated. DISCUSSION: The study Empower-DSD was designed to reduce knowledge gaps regarding the feasibility, acceptance and effects of standardised patient education programmes for children and youth with DSD and their parents. A modular structured patient education programme with four generic and three diagnosis-specific modules based on the ModuS concept previously established for other chronic diseases was developed. The topics, learning objectives and recommended teaching methods are summarised in the structured curricula, one for each diagnosis and age group. At five study centres, 56 trainers were qualified for the implementation of the training programmes. A total of 336 subjects have been already enrolled in the study. The recruitment will go on until August 2022, the last follow-up survey is scheduled for February 2023. The results will help improve multidisciplinary and integrated care for children and youth with DSD and their families. TRIAL REGISTRATION: German Clinical Trials Register, DRKS00023096 . Registered 8 October 2020 - Retrospectively registered.

Unstable Belief Formation and Slowed Decision-making: Evidence That the Jumping-to-Conclusions Bias in Schizophrenia Is Not Linked to Impulsive Decision-making.

BACKGROUND: Jumping-to-conclusions (JTC) is a prominent reasoning bias in schizophrenia (SCZ). While it has been linked to not only psychopathological abnormalities (delusions and impulsive decision-making) but also unstable belief formation, its origin remains unclear. We here directly test to which extend JTC is associated with delusional ideation, impulsive decision-making, and unstable belief formation. METHODS: In total, 45 SCZ patients were compared with matched samples of 45 patients with major depressive disorder (MDD) and 45 healthy controls (HC) as delusions and JTC also occur in other mental disorders and the general population. Participants performed a probabilistic beads task. To test the association of JTC with measures of delusions (Positive and Negative Syndrome Scale [PANSS]positive, PANSSpositive-factor, and Peter Delusions Inventory [PDI]), Bayesian linear regressions were computed. For the link between JTC and impulsive decision-making and unstable beliefs, we conducted between-group comparisons of "draws to decision" (DTD), "decision times" (DT), and "disconfirmatory evidence scores" (DES). RESULTS: Bayesian regression obtained no robust relationship between PDI and DTD (all |R2adj| ≤ .057, all P ≥ .022, all Bayes Factors [BF01] ≤ 0.046; α adj = .00833). Compared with MDD and HC, patients with SCZ needed more time to decide (significantly higher DT in ambiguous trials: all P ≤ .005, r2 ≥ .216; numerically higher DT in other trials). Further, SCZ had unstable beliefs about the correct source jar whenever unexpected changes in bead sequences (disconfirmatory evidence) occurred (compared with MDD: all P ≤ .004 and all r2 ≥ .232; compared with HC: numerically higher DES). No significant correlation was observed between DT and DTD (all P ≥ .050). CONCLUSIONS: Our findings point toward a relationship of JTC with unstable belief formation and do not support the assumption that JTC is associated with impulsive decision-making.

Pubertal development in 46,XY patients with NR5A1 mutations.

PURPOSE: Mutations in the NR5A1 gene, encoding the transcription factor Steroidogenic Factor-1, are associated with a highly variable genital phenotype in patients with 46,XY differences of sex development (DSD). Our objective was to analyse the pubertal development in 46,XY patients with NR5A1 mutations by the evaluation of longitudinal clinical and hormonal data at pubertal age. METHODS: We retrospectively studied a cohort of 10 46,XY patients with a verified NR5A1 mutation and describe clinical features including the external and internal genitalia, testicular volumes, Tanner stages and serum concentrations of LH, FSH, testosterone, AMH, and inhibin B during pubertal transition. RESULTS: Patients who first presented in early infancy due to ambiguous genitalia showed spontaneous virilization at pubertal age accompanied by a significant testosterone production despite the decreased gonadal volume. Patients with apparently female external genitalia at birth presented later in life at pubertal age either with signs of virilization and/or absence of female puberty. Testosterone levels were highly variable in this group. In all patients, gonadotropins were constantly in the upper reference range or elevated. Neither the extent of virilization at birth nor the presence of Müllerian structures reliably correlated with the degree of virilization during puberty. CONCLUSION: Patients with NR5A1 mutations regardless of phenotype at birth may demonstrate considerable virilization at puberty. Therefore, it is important to consider sex assignment carefully and avoid irreversible procedures during infancy.

Glutamatergic Contribution to Probabilistic Reasoning and Jumping to Conclusions in Schizophrenia: A Double-Blind, Randomized Experimental Trial.

BACKGROUND: Impaired probabilistic reasoning and the jumping-to-conclusions reasoning bias are hallmark features of schizophrenia (SCZ), yet the neuropharmacological basis of these deficits remains unclear. Here we tested the hypothesis that glutamatergic neurotransmission specifically contributes to jumping to conclusions and impaired probabilistic reasoning in SCZ. METHODS: A total of 192 healthy participants received either NMDA receptor agonists/antagonists (D-cycloserine/dextromethorphan), dopamine type 2 receptor agonists/antagonists (bromocriptine/haloperidol), or placebo in a randomized, double-blind, between-subjects design. In addition, we tested 32 healthy control participants matched to 32 psychotic inpatients with SCZ-a state associated with compromised probabilistic reasoning due to reduced glutamatergic neurotransmission. All experiments employed two versions of a probabilistic reasoning (beads) task, which required participants to either sample individual amounts of sensory information to infer correct decisions or provide explicit probability estimates for presented sensory information. Our task instantiations assessed both information sampling and explicit probability estimates in different probabilistic contexts (easy vs. difficult conditions) and changing sensory information through random transitions among easy, difficult, and ambiguous trial types. RESULTS: Following administration of D-cycloserine, haloperidol, and bromocriptine, healthy participants displayed data-gathering behavior that was normal compared with placebo and was adequate in the context of all employed task conditions and trial level difficulties. However, healthy participants receiving dextromethorphan displayed a jumping-to-conclusions bias, abnormally increased probability estimates, and overweighting of sensory information. These effects were mirrored in patients with SCZ performing the same versions of the beads task. CONCLUSIONS: Our findings provide novel neuropharmacological evidence linking reduced glutamatergic neurotransmission to impaired information sampling and to disrupted probabilistic reasoning, namely to overweighting of sensory evidence, in patients with SCZ.

Oculopharyngeal muscular dystrophy (OPMD) and dementia in a 75-year-old female.

Oculopharyngeal muscular dystrophy (OPMD) is a relatively rare, adult-onset disorder characterised by proximal limb weakness, progressive eyelid drooping and swallowing difficulties. Preliminary research suggests there could be a link between OPMD and dementia; however, the current literature is relatively limited and inconsistent. This case study describes a 75-year-old female with OPMD, presenting to an older adults community mental health team with memory problems and word finding difficulties. A neuropsychological assessment was carried out. The results of her assessment were difficult to interpret; she demonstrated impairments in most cognitive domains tested and her presentation did not appear to reflect any typical dementia profile. It was thought she was most likely presenting with a dementia; however, the exact aetiology remains unclear. The dementia could be a result of OPMD, vascular changes or both. This report emphasises the need for further research into the possible causal link between OPMD and dementia/cognitive decline.

Mental Health of a Large Group of Adults With Disorders of Sex Development in Six European Countries.

OBJECTIVE: The aim of the study was to evaluate psychiatric symptoms among 1022 persons with various disorders of sex development (DSDs). METHODS: The study was a European multicenter cross-sectional clinical evaluation in six countries. The mean (SD) age of participants was 32.1 (13.4) years. The cohort consisted of 325 individuals with Turner syndrome, 219 individuals with Klinefelter syndrome (KS), female individuals with various XY-DSD conditions (107 with and 67 without androgenization), 87 male individuals with XY-DSD conditions, and 221 female individuals with congenital adrenal hyperplasia. The Hospital Anxiety and Depression Scale, the Short Autism Spectrum Quotient, the Adult Attention-Deficit/Hyperactivity Disorder Self-Report Scale, and self-reported mental health history were used to assess psychiatric symptoms. RESULTS: Across the six DSD diagnostic groups, clinical cutoff symptom scores were reached in 19.5% of participants for anxiety, in 7.1% for depression, in 4.1% for attention-deficit/hyperactivity disorder, and in 9.1% for autism. The mean depression and anxiety scores were higher compared with population norms in men with KS and men with XY-DSD. Compared with participants with other DSD conditions, men with KS reported significantly more mental health symptoms. Self-esteem, satisfaction with care, body dissatisfaction, and experiences of shame were associated with psychiatric symptoms in many DSD conditions. CONCLUSIONS: A substantial minority of adults with DSD, with KS in particular, experience psychiatric morbidity. Across DSD conditions, adults may share feelings of shame. Developing a positive self-esteem and body image may be challenging. Multidisciplinary DSD care that involves specialized mental health support can be of important value. TRIAL REGISTRATION: German Clinical Trials Register DRKS00006072.

Forget-me-some: General versus special purpose models in a hierarchical probabilistic task.

Humans build models of their environments and act according to what they have learnt. In simple experimental environments, such model-based behaviour is often well accounted for as if subjects are ideal Bayesian observers. However, more complex probabilistic tasks require more sophisticated forms of inference that are sufficiently computationally and statistically taxing as to demand approximation. Here, we study properties of two approximation schemes in the context of a serial reaction time task in which stimuli were generated from a hierarchical Markov chain. One, pre-existing, scheme was a generically powerful variational method for hierarchical inference which has recently become popular as an account of psychological and neural data across a wide swathe of probabilistic tasks. A second, novel, scheme was more specifically tailored to the task at hand. We show that the latter model fit significantly better than the former. This suggests that our subjects were sensitive to many of the particular constraints of a complex behavioural task. Further, the tailored model provided a different perspective on the effects of cholinergic manipulations in the task. Neither model fit the behaviour on more complex contingencies that competently. These results illustrate the benefits and challenges that come with the general and special purpose modelling approaches and raise important questions of how they can advance our current understanding of learning mechanisms in the brain.

Oestrogen versus androgen in hormone-replacement therapy for complete androgen insensitivity syndrome: a multicentre, randomised, double-dummy, double-blind crossover trial.

BACKGROUND: Women with complete androgen insensitivity syndrome (CAIS) after gonadectomy have complained about reduced psychological wellbeing and sexual satisfaction. The aim of this study was to compare the effectiveness of hormone-replacement therapy with either androgen or oestrogen in women with 46,XY karyotype and CAIS after gonadectomy. METHODS: This national, multicentre, double-blind, randomised crossover trial was performed at three university medical centres and three specialised treatment institutions in Germany. Eligible participants were women aged 18-54 years with 46,XY karyotype, genetically diagnosed CAIS, and removed gonads. Participants were randomly assigned (14:12) by a central computer-based minimisation method to either oestradiol 1·5 mg/day for 6 months followed by crossover to testosterone 50 mg/day for 6 months (sequence A) or to testosterone 50 mg/day for 6 months followed by crossover to oestradiol 1·5 mg/day for 6 months (sequence B). Participants also received oestradiol or testosterone dummy to avoid identification of the active substance. All participants received oestradiol 1·5 mg/day during a 2 months' run-in phase. The primary outcome was mental health-related quality of life, as measured with the standardised German version of the SF-36 questionnaire. Secondary outcomes were psychological wellbeing, as measured with the Brief Symptom Inventory (BSI), sexual function, as measured with the Female Sexual Function Index (FSFI), and somatic effects, such as signs of virilisation and effects on metabolic blood values. The primary analysis included all patients who were available at least until visit 5, even if protocol violations occurred. The safety analysis included all patients who received at least oestradiol during the run-in phase. This trial is registered with the German Clinical Trials Register, number DRKS00003136, and with the European Clinical Trials Database, number 2010-021790-37. FINDINGS: We enrolled 26 patients into the study, with the first patient enrolled on Nov 7, 2011, and the last patient leaving the study on Jan 23, 2016. 14 patients were assigned to sequence A and 12 were assigned to sequence B. Ten participants were withdrawn from the study, two of whom attended at least five visits and so could be included in the primary analysis. Mental health-related quality of life did not differ between treatment groups (linear mixed model, p=0·794), nor did BSI scores for psychological wellbeing (global severity index, p=0·638; positive symptom distress index, p=0·378; positive symptom total, p=0·570). For the FSFI, testosterone was superior to oestradiol only in improving sexual desire (linear mixed model, p=0·018). No virilisation was observed, and gonadotrophin concentrations remained stable in both treatment groups. Oestradiol and testosterone concentrations changed substantially during the study in both treatment groups. 28 adverse events were reported for patients receiving oestradiol (23 grade 1 and five grade 2), and 38 adverse events were reported for patients receiving testosterone (34 grade 1, three grade 2, and one grade 3). One serious adverse event (fibrous mastopathy) and 20 adverse events (16 grade 1 and four grade 2) were reported during the run-in phase, and 12 adverse events during follow-up (nine grade 1 and three grade 2). INTERPRETATION: Testosterone was well tolerated and as safe as oestrogen for hormone-replacement therapy. Testosterone can be an alternative hormone substitution in CAIS, especially for woment with reduced sexual functioning. FUNDING: German Federal Ministry of Education and Research.

Quality of health care in adolescents and adults with disorders/differences of sex development (DSD) in six European countries (dsd-LIFE).

BACKGROUND: To investigate the association between the structural quality of care and patient satisfaction with care in individuals with disorders/ differences of sex development (DSD). METHODS: A multicenter cross-sectional comparative study was conducted in 14 clinics in six European countries. We assessed the level of structural quality of care in each center using a self-constructed measure (Center Score) and the level of participant satisfaction with care using the customer satisfaction questionnaire (CSQ-4) and an adopted version of the Youth Health Care - Satisfaction, Utilization & Needs (YHC-SUN-SF). Data were obtained from individuals with Turner Syndrome (261), Klinefelter Syndrome (173), 46, XX congenital adrenal hyperplasia (190) and XY-DSD (257). RESULTS: We found large variations between the scores for structural quality of care both within a diagnostic group and within a country; the overall association between participant satisfaction with the center score was significant. CONCLUSIONS: Comparative effectiveness research across Europe can lead to more insight on beneficial structures and processes and the overall strategy to care for people with rare diseases in general and specific conditions such as disorders/ differences of sex development. Appreciation of higher levels of structural quality of the centers in this study supports the concept of comprehensive care. TRIAL REGISTRATION: German Clinical Trials Register: Registration identification number: DRKS00006072 , date of registration April 17th, 2014. DRKS00006072 (German Clinical Trials Register).

Endoscopy and Laparoscopy in Disorders of Sex Development.

Endoscopy and laparoscopy are used for the assessment of disorders of sex development (DSD) and therapeutic interventions. Endoscopy (urethra-cystoscopy, vaginoscopy) is especially useful when vaginal or urethral surgery is planned. It is also valuable for the assessment of complications. Laparoscopy is used to identify sex ducts and gonads and to perform minimally invasive abdominal and pelvic surgery. This article reviews clinical indications, limitations, findings, and their reporting. It further discusses the impact of these findings on care in typical clinical situations.

Pubertal Development in17Beta-Hydroxysteroid Dehydrogenase Type 3 Deficiency
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BACKGROUND: 17ß-hydroxysteroid dehydrogenase (17ß-HSD) type 3 deficiency is an autosomal recessive disorder with diminished testosterone synthesis and consequently underandrogenisation. 46,XY patients with 17ß-HSD type 3 deficiency are often assigned a female sex at birth but have a high virilisation potential at the time of puberty. METHODS: We studied four 46,XY patients with 17ß-HSD type 3 deficiency at puberty with regard to the underlying mutations, the hormone values, and the clinical findings. RESULTS: Three patients were initially assigned a female sex and 1 was assigned a male sex. All had relevant mutations in the HSD17B3 gene. The 2 patients with deleterious mutations had lower testosterone values at the time of puberty than the patients with possible residual activity of 17ß-HSD type 3. One of the latter patients changed to male gender. CONCLUSION: All 4 patients with 17ß-HSD type 3 deficiency synthesized relevant amounts (>0.7 µg/L) of testosterone at puberty, which lead to variable androgenisation. In patients with presumable residual activity of the mutated enzyme, testosterone values in the male reference range can be achieved, thereby inducing male pubertal development. These patients should possibly be assigned a male sex. Any surgical intervention should be avoided until the patients are old enough to consider their options of medical and surgical intervention.
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Pharmacological Fingerprints of Contextual Uncertainty.

Successful interaction with the environment requires flexible updating of our beliefs about the world. By estimating the likelihood of future events, it is possible to prepare appropriate actions in advance and execute fast, accurate motor responses. According to theoretical proposals, agents track the variability arising from changing environments by computing various forms of uncertainty. Several neuromodulators have been linked to uncertainty signalling, but comprehensive empirical characterisation of their relative contributions to perceptual belief updating, and to the selection of motor responses, is lacking. Here we assess the roles of noradrenaline, acetylcholine, and dopamine within a single, unified computational framework of uncertainty. Using pharmacological interventions in a sample of 128 healthy human volunteers and a hierarchical Bayesian learning model, we characterise the influences of noradrenergic, cholinergic, and dopaminergic receptor antagonism on individual computations of uncertainty during a probabilistic serial reaction time task. We propose that noradrenaline influences learning of uncertain events arising from unexpected changes in the environment. In contrast, acetylcholine balances attribution of uncertainty to chance fluctuations within an environmental context, defined by a stable set of probabilistic associations, or to gross environmental violations following a contextual switch. Dopamine supports the use of uncertainty representations to engender fast, adaptive responses.

[Prevalence of Disturbed Eating Behavior in Children and Adolescents with Type 1 Diabetes: Assessment and Comparison to Healthy Peers--Results of a Multicenter Questionnaire-based Study]. / Prävalenz gestörten Essverhaltens bei Typ 1 Diabetes im Kindes- und Jugendalter: Erfassungsmöglichkeiten und Vergleich mit gesunden Gleichaltrigen--Ergebnisse einer multizentrischen Fragebogenstudie.

INTRODUCTION: Published data on prevalence of disturbed eating behavior in youth with type 1 diabetes are heterogeneous. This study assesses the prevalence rate of disturbed eating behavior in a representative German sample of children and adolescents with type 1 diabetes. The prevalence rate is compared to the one published for a national sample of healthy peers. Furthermore prospects as well as limits of a generic screening tool used to identify disturbed eating behavior are compared to those of a diabetes specific screening tool. MATERIAL AND METHODS: A total of 246 children and adolescents (age: 11-19 years) with type 1 diabetes, from 6 pediatric diabetes centers in Germany, completed the generic SCOFF questionnaire and the diabetes specific Diabetes Eating Problem Survey-Revised (DEPS-R) to assess their eating behavior. Prevalence data were compared to representative data from a nationwide survey in Germany (KiGGS-study). RESULTS: A total of 16.3% of the children and adolescents with type 1 diabetes scored above the SCOFF cut-off (≥ 2) (24.2% of the girls and 8.9% of the boys). The percentages in the healthy controls were 28.9% for girls and 15.2% for boys. Compared to this the prevalence of disturbed eating behavior was lower in the diabetes group (p=0.017 and p<0.001). According to the diabetes specific DEPS-R 11.2% of the boys and 13.2% of the girls with type 1 diabetes practiced insulin-purging. The association between SCOFF-scores and the items referring to insulin-purging in DEPS-R, was stronger for girls than for boys (r=0.437 vs. r=0.144). Among the young people with type 1 diabetes DEPS-R-scores showed stronger associations to the quality of metabolic control (HbA1c) than the SCOFF (boys: r=0.357 vs. r=0.217 and girls: r=0.368 vs. r=0.131). DISCUSSION: Children and adolescents with type 1 diabetes are not more frequently affected by disturbed eating behavior than their healthy peers. Particularly boys with type 1 diabetes practicing insulin-purging, are not reliably detected by a generic screening tool. CONCLUSION: As part of long-term care a diabetes specific screening tool should be used to identify adolescents with type 1 diabetes and disturbed eating behavior more reliably.

Computations of uncertainty mediate acute stress responses in humans.

The effects of stress are frequently studied, yet its proximal causes remain unclear. Here we demonstrate that subjective estimates of uncertainty predict the dynamics of subjective and physiological stress responses. Subjects learned a probabilistic mapping between visual stimuli and electric shocks. Salivary cortisol confirmed that our stressor elicited changes in endocrine activity. Using a hierarchical Bayesian learning model, we quantified the relationship between the different forms of subjective task uncertainty and acute stress responses. Subjective stress, pupil diameter and skin conductance all tracked the evolution of irreducible uncertainty. We observed a coupling between emotional and somatic state, with subjective and physiological tuning to uncertainty tightly correlated. Furthermore, the uncertainty tuning of subjective and physiological stress predicted individual task performance, consistent with an adaptive role for stress in learning under uncertain threat. Our finding that stress responses are tuned to environmental uncertainty provides new insight into their generation and likely adaptive function.

Evidence for Optimal Integration of Visual Feature Representations across Saccades.

We explore the visual world through saccadic eye movements, but saccades also present a challenge to visual processing by shifting externally stable objects from one retinal location to another. The brain could solve this problem in two ways: by overwriting preceding input and starting afresh with each fixation or by maintaining a representation of presaccadic visual features in working memory and updating it with new information from the remapped location. Crucially, when multiple objects are present in a scene the planning of eye movements profoundly affects the precision of their working memory representations, transferring limited memory resources from fixation toward the saccade target. Here we show that when humans make saccades, it results in an update of not just the precision of representations but also their contents. When multiple item colors are shifted imperceptibly during a saccade the perceived colors are found to fall between presaccadic and postsaccadic values, with the weight given to each input varying continuously with item location, and fixed relative to saccade parameters. Increasing sensory uncertainty, by adding color noise, biases updating toward the more reliable input, which is consistent with an optimal integration of presaccadic working memory with a postsaccadic updating signal. We recover this update signal and show it to be tightly focused on the vicinity of the saccade target. These results reveal how the nervous system accumulates detailed visual information from multiple views of the same object or scene. SIGNIFICANCE STATEMENT: This study examines the consequences of saccadic eye movements for the internal representation of visual objects. A saccade shifts the image of a stable visual object from one part of the retina to another. We show that visual representations are built up over these different views of the same object, by combining information obtained before and after each saccade. The weights given to presaccadic and postsaccadic information are determined by the relative reliability of each input. This provides evidence that the visual system combines inputs over time in a statistically optimal way.

46,XY Gonadal Dysgenesis due to a Homozygous Mutation in Desert Hedgehog (DHH) Identified by Exome Sequencing.

BACKGROUND: 46,XY disorders of sex development (DSD) comprise a heterogeneous group of congenital conditions. Mutations in a variety of genes can affect gonadal development or androgen biosynthesis/action and thereby influence the development of the internal and external genital organs. OBJECTIVE: The objective of the study was to identify the genetic cause in two 46,XY sisters of a consanguineous family with DSD and gonadal tumor formation. METHODS: We used a next-generation sequencing approach by exome sequencing. Electrophysiological and high-resolution ultrasound examination of peripheral nerves as well as histopathological examination of the gonads were performed. RESULTS: We identified a novel homozygous R124Q mutation in the desert hedgehog gene (DHH), which alters a conserved residue among the three mammalian Hedgehog ligands sonic hedgehog, Indian hedgehog, and desert hedgehog. No other relevant mutations in DSD-related genes were encountered. The gonads of one patient showed partial gonadal dysgenesis with loss of Leydig cells in tubular areas with seminoma in situ and a hyperplasia of Leydig cell-like cells expressing CYP17A1 in more dysgenetic parts of the gonad. In addition, both patients suffer from a polyneuropathy. High-resolution ultrasound revealed a structural change of peripheral nerve structure that fits well to a minifascicle formation of peripheral nerves. CONCLUSION: Mutations in DHH play a role in 46,XY gonadal dysgenesis and are associated with seminoma formation and a neuropathy with minifascicle formation. Gonadal dysgenesis in these cases may be due to impairment of Sertoli cell-Leydig cell interaction during gonadal development.

Interaction between visual and motor cortex: a transcranial magnetic stimulation study.

The major link between the visual and motor systems is via the dorsal stream pathways from visual to parietal and frontal areas of the cortex. Although the pathway appears to be indirect, there is evidence that visual input can reach the motor cortex at relatively short latency. To shed some light on its neural basis, we studied the visuomotor interaction using paired transcranial magnetic stimulation (TMS). Motor-evoked potentials (MEPs) were recorded from the right first dorsal interosseous in sixteen healthy volunteers. A conditioning stimulus (CS) was applied over the phosphene hotspot of the visual cortex, followed by a test stimulus over the left primary motor cortex (M1) with a random interstimulus interval (ISI) in range 12-40 ms. The effects of paired stimulation were retested during visual and auditory reaction-time tasks (RT). Finally, we measured the effects of a CS on short-interval intracortical inhibition (SICI). At rest, a CS over the occiput significantly (P < 0.001) suppressed test MEPs with an ISI in the range 18-40 ms. In the visual RT, inhibition with an ISI of 40 ms (but not 18 ms) was replaced by a time-specific facilitation (P < 0.001), whereas, in the auditory RT, the CS no longer had any effect on MEPs. Finally, an occipital CS facilitated SICI with an ISI of 40 ms (P < 0.01). We conclude that it is possible to study separate functional connections from visual to motor cortices using paired-TMS with an ISI in the range 18-40 ms. The connections are inhibitory at rest and possibly mediated by inhibitory interneurones in the motor cortex. The effect with an ISI of 40 ms reverses into facilitation during a visuomotor RT but not an audiomotor RT. This suggests that it plays a role in visuomotor integration.