Solution structure of multi-domain protein ER-60 studied by aggregation-free SAXS and coarse-grained-MD simulation

Multi-domain proteins (MDPs) show a variety of domain conformations under physiological conditions, regulating their functions through such conformational changes. One of the typical MDPs, ER-60 which is a protein folding enzyme, has a U-shape with four domains and is thought to have different domain conformations in solution depending on the redox state at the active centres of the edge domains. In this work, an aggregation-free small-angle X-ray scattering revealed that the structures of oxidized and reduced ER-60 in solution are different from each other and are also different from those in the crystal. Furthermore, structural modelling with coarse-grained molecular dynamics simulation indicated that the distance between the two edge domains of oxidized ER-60 is longer than that of reduced ER-60. In addition, one of the edge domains has a more flexible conformation than the other

A questionnaire-based comparative study of postoperative quality of life between laryngotracheal separation and tracheoesophageal diversion

Purpose: Whether tracheoesophageal diversion (TED) is preferable to laryngotracheal separation (LTS) is unclear. This study examined the need for tracheoesophageal anastomosis by reviewing complications after TED and LTS and administering a questionnaire on postoperative quality of life.Patients and methods: Medical records of TED/LTS cases performed at a single institution from 2003 to 2015 were retrospectively reviewed and a questionnaire was administered to parents of patients at an outpatient visit.Results: A total of 40 TED and 18 LTS cases were included. Complications occurred in six TED cases and one LTS case, with no significant differences between groups (P=0.42). A total of 22 parents of patients (TED 16 cases; LTS six cases) completed the questionnaire. Voice production was reported in three TED cases and two LTS cases. Patients indicated that suctions were ‘decreased’ in 13 and ‘unchanged’ in two TED cases, but ‘decreased’ in one and ‘unchanged’ in five LTS cases (P=0.0055). Readmissions were ‘increased’ in one and ‘decreased’ in 14 TED cases, but ‘decreased’ in three and ‘unchanged’ in three LTS cases (P=0.015).Conclusion: Postoperative complication rate was equivalent between groups, and the numbers of suctions and readmissions were decreased in the TED group. Therefore, tracheoesophageal anastomosis should be performed more commonly.Keywords: complication, laryngotracheal separation, quality of life questionnaire, tracheoesophageal diversio

Elucidation of the mechanism of subunit exchange in αB crystallin oligomers

AlphaB crystallin (αB-crystallin) is a key protein for maintaining the long-term transparency of the eye lens. In the eye lens, αB-crystallin is a “dynamical” oligomer regulated by subunit exchange between the oligomers. To elucidate the unsettled mechanism of subunit exchange in αB-crystallin oligomers, the study was carried out at two different protein concentrations, 28.5 mg/mL (dense sample) and 0.45 mg/mL (dilute sample), through inverse contrast matching small-angle neutron scattering. Interestingly, the exchange rate of the dense sample was the same as that of the dilute sample. From analytical ultracentrifuge measurements, the coexistence of small molecular weight components and oligomers was detected, regardless of the protein concentration. The model proposed that subunit exchange could proceed through the assistance of monomers and other small oligomers; the key mechanism is attaching/detaching monomers and other small oligomers to/from oligomers. Moreover, this model successfully reproduced the experimental results for both dense and dilute solutions. It is concluded that the monomer and other small oligomers attaching/detaching mainly regulates the subunit exchange in αB-crystallin oligomer

Dynamics of proteins with different molecular structures under solution condition

Incoherent quasielastic neutron scattering (iQENS) is a fascinating technique for investigating the internal dynamics of protein. However, low flux of neutron beam, low signal to noise ratio of QENS spectrometers and unavailability of well-established analyzing method have been obstacles for studying internal dynamics under physiological condition (in solution). The recent progress of neutron source and spectrometer provide the fine iQENS profile with high statistics and as well the progress of computational technique enable us to quantitatively reveal the internal dynamic from the obtained iQENS profile. The internal dynamics of two proteins, globular domain protein (GDP) and intrinsically disordered protein (IDP) in solution, were measured with the state-of-the art QENS spectrometer and then revealed with the newly developed analyzing method. It was clarified that the average relaxation rate of IDP was larger than that of GDP and the fraction of mobile H atoms of IDP was also much higher than that of GDP. Combined with the structural analysis and the calculation of solvent accessible surface area of amino acid residue, it was concluded that the internal dynamics were related to the highly solvent exposed amino acid residues depending upon protein’s structure

Psicología: aspectos fundamentales de la formación y la profesión

El aspecto de la práctica clínica ha sido abordado primeramente por la doctora Córdoba Basulto, desde la experiencia, y de manera muy breve profundiza en el ámbito de la Psicología de la salud, rescata y enfatiza el aspecto de la atención e intervención al paciente de urología, colocándolo en la parte de sujeto y no de enfermedad. Nuevamente señalando el trabajo multidisciplinario donde cada agente contribuye con la atención. Desde una perspectiva meramente clínica y específicamente con la experiencia del psicoanálisis, Márquez, Guadarrama, López y Huitrón nos permiten observar la postura de la adolescencia en el proceso terapéutico, indicando que la mejor forma de tratar a un adolescente no es lo individual, ni lo familiar, sino lo grupal.Este libro es una compilación de aportaciones que permiten observar el estado actual de la psicología en México, permitiendo vislumbrar los retos reales que no solamente tienen los alumnos que asumir en su formación profesional, sino todos aquellos que se encuentran laborando en esta basta disciplina. En este sentido, el mundo globalizado y el empleo exagerado de la tecnología se convierten en nuevas exigencias que propician a su vez nuevas formas, no sólo de atención, sino de estudio e investigación que le permitan la comprensión del comportamiento humano. La Psicología mexicana en los últimos años ha dejado de ser dogmática para convertirse en una ciencia amplia y de visión, lo que le ha permitido incursionar en nuevos campos de conocimiento como el de la psicología de la salud o de la psicología criminal. Es decir ha dejado de ser una psicología de diagnóstico y clínica para convertirse en una ciencia que asume al individuo como un ser social, complejo o bien como algunos ya lo han señalado como un ente psicosociobiológico

Standard spontaneous ventilation in children under anaesthesia.

The respiratory dead space may be defined as the space within the oro- nasal cavity, pharynx, larynx and tracheo-bronchial tree which does not participate in gas exchange. Even though the dead space is considered as not participating in respiratory gas exchange, it is important in that it serves as a functional buffer to protect against any unphysiological effects resulting from sudden changes in the nature of the gas breathed. [...

The Structure of an Al-Ni-Ru Monoclinic Phase Al 13 (Ru,Ni) 4

The structure of a Ni-substituted Al 13 (Ru,Ni) 4 phase was analyzed by single crystal X-ray diffraction. The present analysis revealed the distribution of Ni at five heavy metal sites of Ru/Ni(1), Ru/Ni(2), Ru/Ni(3), Ru/Ni(4) and Ru/Ni(5). The anisotropic contraction of the corresponding coordination polyhedra around heavy metal sites was also suggested together with a variation of lattice constants as a function of Ni content