A dopamine receptor D2 genetic polymorphism associated with transition to mental disorders in a cohort of individuals with at-risk mental state for psychosis

Objectives: To test the association of 45 single nucleotide polymorphisms (SNPs) with transition to psychiatric disorders in a cohort of individuals at ultrahigh risk (UHR) mental state for psychosis. Methods: Through general population screening, 88 non-help-seeking UHR subjects and 130 healthy control individuals were genotyped for 45 SNPs related to psychosis. They were followed for a mean of 2.5 years, and conversion to psychotic and to general psychiatric disorders was assessed. Genotype frequencies between controls, converters, and non-converters were analyzed. Results: There were no differences in sociodemographics between controls and UHR. Also, UHR converters and non-converters had no differences in their baseline symptoms scores. The dopamine receptor D2 gene (DRD2) SNP rs6277 was significantly more common among UHR who transitioned to psychosis (p < 0.001) and to UHR who transitioned to any psychiatric disorders (p = 0.001) when compared to UHR who did not transition. The rs6277 T allele was related to psychiatric morbidity in a dose-response fashion, being significantly more frequent in UHR converters than UHR non-converters and control subjects (p = 0.003). Conclusion: Our findings suggest that rs6277 could potentially constitute a genetic marker of transition to psychiatric disorders in subjects with at-risk mental states, warranting further investigation in larger samples.

Colgajo giratorio retroauricular / Retroauricular flip-flop flap

Resumen El colgajo retroauricular en isla (flip-flop flap) fue descrito por Masson en 1972 y consiste en tejido dermoepidérmico irrigado por un pedículo de patrón aleatorio subcutáneo de ramas de la arteria auricular posterior. Proviene de la región mastoidea y retroauricular y aporta buena cobertura para la región anteromedial del pabellón auricular. Se describen dos casos, en que se realizó cobertura inmediata secundario a un defecto de la concha auricular posterior a resección neoplásica, obteniendo resultados satisfactorios y sin complicaciones.

Abstract The retroauricular island flap (flip-flop flap), was described by Masson in 1972 and consists on dermoepidermal tissue irrigated by a random subcutaneous pedicle of branches of the posterior auricular artery. It comes from the mastoid and retroauricular region and provides a good coverage for the anteromedial region of the pinna. Two cases are described, in which immediate coverage was performed secondary to a defect in the auricular concha after a neoplastic resection, obtaining satisfactory results without complications.

MsbA ATP-binding cassette (ABC) transporter of E. coli: Structure and possible flippase mechanism.

ATP-binding cassette (ABC) transporters utilize the energy present in cellular ATP to drive the translocation of structurally diverse set of solutes across the membrane barriers of eubacteria, archaebacteria and eukaryotes. In bacteria, these transporters are considered to be important virulence factors because they play role in nutrient uptake and in the secretion of toxins. The advances in structural determination and functional analysis of bacterial transporters have greatly increased our understanding of the mechanism of transport of these ABC transporters. Although progress in the field of structural biology has been made with the prokaryotic family members, it is likely that eukaryotic transporters will utilize the same mechanisms for translocation process. In this review, we summarize the function of the known MsbA ABC transporters in E. coli and mechanistic insights from structural and possible flippase mechanism studies.

Postauricular Island Pedicle Flap ("Flip-Flop" Flap) for Reconstruction of the External Ear Defect / 대한피부과학회지

About six percent of head and neck cancers occur on the external ears. Excision of the cancer can cause changes of morphology and poor cosmesis. Reconstruction of ear defects presents a unique and notable challenge to the dermatologic surgeons. This is due to the complex architecture of the external ear which is difficult to duplicate surgically. Several methods are available for reconstruction of defects to the external ear. However, the diversity of external ear shapes shows how difficult it is to achieve a certain solution to this problem. Postauricular island pedicle flap was initially reported as a technique for reconstruction of small defects of the concha after excision, and has since been used successfully in the repair of more extensive defects involving not only the concha, but also the antihelix and external auditory meatus. We report two cases of auricular squamous cell carcinoma in which the skin defect is reconstructed by a postauricular island pedicle flap ("flip-flop" flap).

Hydrogen bonding patterns and dynamics in the hydration of biological macromolecules.

In crystalline cyclodextrin hydrates O–H . . . Ο hydrogen bonds occur in homodromic chainlike and cyclic motifs. In β-cyclodextrin· 11 H2O, where OH-groups are disordered, flip-flop hydrogen bonds O–(1/2H) . . . (1/2H)–O are found which represent a dynamical equilibrium O–H . . . . . . H–O. Detailed insight into otherwise hidden structural aspects of hydration and water structure (clusters) become available.