Diverse selection pressures shaping the genetic architecture of behçet disease susceptibility.

Behçet disease (BD) is a polygenic, multifactorial, multisystem inflammatory condition with unknown etiology. Global distribution of BD is geographically structured, highest prevalence observed among East Asian, Middle Eastern, and Mediterranean populations. Although adaptive selection on a few BD susceptibility loci is speculated, a thorough evolutionary analysis on the genetic architecture of BD is lacking. We aimed to understand whether increased BD risk in the human populations with high prevalence is due to past selection on BD associated genes. We performed population genetics analyses with East Asian (high BD prevalence), European (low/very low BD prevalence), and African (very low/no BD prevalence) populations. Comparison of ancestral and derived alleles' frequencies versus their reported susceptible or protective effect on BD showed both derived and ancestral alleles are associated with increased BD risk. Variants showing higher risk to and more significant association with BD had smaller allele frequency differences, and showed less population differentiation compared to variants that showed smaller risk and less significant association with BD. Results suggest BD alleles are not unique to East Asians but are also found in other world populations at appreciable frequencies, and argue against selection favoring these variants only in populations with high BD prevalence. BD associated gene analyses showed similar evolutionary histories driven by neutral processes for many genes or balancing selection for HLA (Human Leukocyte Antigen) genes in all three populations studied. However, nucleotide diversity in several HLA region genes was much higher in East Asians suggesting selection for high nucleotide and haplotype diversity in East Asians. Recent selective sweep for genes involved in antigen recognition, peptide processing, immune and cellular differentiation regulation was observed only in East Asians. We conclude that the evolutionary processes shaping the genetic diversity in BD risk genes are diverse, and elucidating the underlying specific selection mechanisms is complex. Several of the genes examined in this study are risk factors (such as ERAP1, IL23R, HLA-G) for other inflammatory diseases. Thus, our conclusions are not only limited to BD but may have broader implications for other inflammatory diseases.

Do Musicians and Non-musicians Differ in Speech-on-Speech Processing?

Earlier studies have shown that musically trained individuals may have a benefit in adverse listening situations when compared to non-musicians, especially in speech-on-speech perception. However, the literature provides mostly conflicting results. In the current study, by employing different measures of spoken language processing, we aimed to test whether we could capture potential differences between musicians and non-musicians in speech-on-speech processing. We used an offline measure of speech perception (sentence recall task), which reveals a post-task response, and online measures of real time spoken language processing: gaze-tracking and pupillometry. We used stimuli of comparable complexity across both paradigms and tested the same groups of participants. In the sentence recall task, musicians recalled more words correctly than non-musicians. In the eye-tracking experiment, both groups showed reduced fixations to the target and competitor words' images as the level of speech maskers increased. The time course of gaze fixations to the competitor did not differ between groups in the speech-in-quiet condition, while the time course dynamics did differ between groups as the two-talker masker was added to the target signal. As the level of two-talker masker increased, musicians showed reduced lexical competition as indicated by the gaze fixations to the competitor. The pupil dilation data showed differences mainly in one target-to-masker ratio. This does not allow to draw conclusions regarding potential differences in the use of cognitive resources between groups. Overall, the eye-tracking measure enabled us to observe that musicians may be using a different strategy than non-musicians to attain spoken word recognition as the noise level increased. However, further investigation with more fine-grained alignment between the processes captured by online and offline measures is necessary to establish whether musicians differ due to better cognitive control or sound processing.

Distal scar-to-midline distance in pilonidal Limberg flap surgery is a recurrence-promoting factor: A multicenter, case-control study.

BACKGROUND: The Limberg flap (LF) procedure is widely performed for the treatment of sacrococcygeal pilonidal sinus (SPS); however, recurrences continues to be observed. The aim of this study was to assess the relationship between LF designs and the risk of SPS recurrence. METHODS: Sixty-one cases with recurrent disease (study group) and 194 controls, with a minimum of 5 recurrence-free years following surgery (control group), were included in the study. LF reconstructions performed in each group were classified as off-midline closure (OMC) and non-OMC types. Subsequently, the 2 groups were analyzed. RESULTS: After adjustment for all variables, non-OMC types showed the most prominent correlation with recurrence, followed by interrupted suturing type, family history of SPS, smoking, prolonged healing time, and younger age. The best cut-off value for the critical distance from the midline was found to be 11 mm (with 72% sensitivity and 95% specificity for recurrence). CONCLUSIONS: We recommend OMC modifications, with the flap tailored to create a safe margin of at least 2 cm between the flap borders and the midline.

Umbilical Pilonidal Sinus, an Underestimated and Little-Known Clinical Entity: Report of Two Cases.

BACKGROUND Umbilical pilonidal sinus (UPS) is a rare disease of young, hirsute, dark men with deep navels and poor personal hygiene. UPS could easily be misdiagnosed and mistreated due to its rarity and lack of awareness of the condition by physicians. However, the diagnosis is easy to establish with physical examination and a detailed history. Although it is being diagnosed and reported more frequently, there is still no consensus regarding best treatment options. CASE REPORT In this report, we present two cases of UPS, one in a man and one in a woman, who had typical symptoms of pain, swelling, and intermittent malodorous discharge from the umbilicus. They had small sinus openings with hair protruding deep in the navel. Because these two patients had previous histories of failed conservative treatments, an umbilicus preserving surgery was performed for both cases. Wounds were healed in 2-3 weeks with acceptable cosmetic results. During a more than 2 year follow-up period, there were no signs of recurrence. CONCLUSIONS In a patient presenting with a history of intermittent discharge, itching, pain, or bleeding from the umbilicus and the presence of granulation tissue with or without protruding hair and periumbilical dermatitis, the diagnosis should consider UPS, even in female patients. Treatment generally depends on the severity of the disease, ranging from good personal hygiene to surgical excision of umbilical complex. The treatment of choice for chronic intermittent cases is surgical removal of the affected portion; paying special attention to cosmetic appearance.