Skeletal Muscle Mass Indices in Healthy Young Mexican Adults Aged 20–40 Years: Implications for Diagnoses of Sarcopenia in the Elderly Population

Background and Objectives. Skeletal muscle and skeletal muscle indices in young adults from developing countries are sparse. Indices and the corresponding cut-off points can be a reference for diagnoses of sarcopenia. This study assessed skeletal muscle using dual-energy X-ray absorptiometry (DXA) in healthy male and female subjects aged 20–40 years and compared their appendicular skeletal muscle mass (ASM) and total-body skeletal muscle (TBSM) indices using certain cut-off points published in the literature. Methods. A sample of 216 healthy adults men and women from northwest Mexico was included. Body composition was assessed by DXA and several published DXA-derived skeletal muscle indices were compared. Results. Both, ASM and TBSM were higher in men compared to the women group (23.0 ± 3.4 versus 15.9 ± 1.6 kg; P<0.05 and 26.5 ± 4.1 versus 16.9 ± 1.9 kg; P<0.05, resp.). These differences were also valid for both indices. When derived cut-off points were compared with the most reported indices, significant differences were found. Interpretation and Conclusion. Published cut-off points from Caucasians are higher than cut-off point derived in this sample of Mexican subjects. The new DXA-derived cut-off points for ASM proposed herein may improve diagnoses of sarcopenia in the geriatric Mexican population

TIC: A Stokes inversion code for scattering polarization with partial frequency redistribution and arbitrary magnetic fields

We present the Tenerife Inversion Code (TIC), which has been developed to infer the magnetic and plasma properties of the solar chromosphere and transition region via full-Stokes inversion of polarized spectral lines. The code is based on the HanleRT forward engine, which takes into account many of the physical mechanisms that are critical for a proper modeling of the Stokes profiles of spectral lines originating in the tenuous and highly dynamic plasmas of the chromosphere and transition region: quantum level population imbalance and interference (atomic polarization), frequency coherence effects in polarized resonance scattering (partial frequency redistribution), and the impact of arbitrary magnetic fields on the atomic polarization and the radiation field. We present first results of atmospheric and magnetic inversions, and discuss future developments for the project.Comment: 17pages, 7 figures. Accepted for publication in The Astrophysical Journa

Living robotic donor nephrectomy. The first case in Latin America

Indexación: Web of Science; Scielo.Introducción: La donación renal en pacientes vivos relacionados es la mejor alternativa de tratamiento para pacientes con insuficiencia renal crónica. La cirugía abierta es el procedimiento de elección; sin embargo, la nefrectomía laparoscópica se ha convertido en una opción viable en centros con experiencia. Con el propósito de disminuír los tiempos de la curva de aprendizaje, algunos centros han introducido la nefrectomía robótica del donante vivo como una opción quirúrgica. Objetivo: Presentar la primera nefrectomía robótica del donante vivo realizada en Latinoamérica. Caso clínico: Paciente de 50 años, esposo, donante vivo relacionado, por afinidad (esposo-esposa). La receptora tiene 54 años con antecedente de insuficiencia renal crónica terminal en espera de ingreso a programa de hemodiálisis. Se realizó nefrectomía robótica izquierda del donante utilizando el sistema robótico da Vinci Si® (Intuitive Surgical, Sunnyvale CA.) mediante abordaje transperitoneal. El tiempo quirúrgico total fue de 188 min, con un sangrado estimado de 300 ml., y un tiempo de isquemia de 6 min. El injerto presentó inicio inmediato de la función. Ambos pacientes fueron dados de alta a las 72 h. Conclusión: La nefrectomía robótica del donante vivo para trasplante es una alternativa segura y factible. Comunicaciones con series con mayor número de pacientes, son necesarias para establecer su definitivo rol.Introduction: Living donor nephrectomy is the best alternative of treatment for patients with chronic renal disease. Even though open surgery remains the gold standard for donor nephrectomy, laparoscopic surgery has become a feasible alternative in referral centers. To minimize the long learning curve associated with this procedure, some centers have introduced robotic donor nephrectomy as a surgical option. Aim: To present the first robotic-assisted laparoscopic donor nephrectomy in Latin America. Clinical case: The donor is a 50 years old male, living-related to the recipient by affinity (husband/wife). The recipient is a 54 years old female with history of end-stage renal disease waiting to initiate dialysis program. A left transperitoneal robotic-assisted laparoscopic nephrectomy employing the da Vinci Si® (Intuitive Surgical, Sunnyvale CA.) is performed. Mean operative time was 188 minutes with an estimated blood loss of 300 ml. Mean ischemia time was 6 minutes. The graft presented immediate function. Both patients were discharged at 72 h. Conclusion: Living donor robotic-assisted laparoscopic nephrectomy is a safe and viable procedure. Larger series are needed to establish its role.http://ref.scielo.org/p438d

Introducción al Análisis e Implementación de Sistemas de Control Automático

Introducción al Análisis e implementación de Sistemas de Control Automático es un libro de texto para estudiantes universitarios y profesionales interesados en el estudio de los conceptos básicos de la teoría de control en el dominio del tiempo y de la frecuencia con aplicaciones en el diseño clásico y moderno de los sistemas de control automático. En esta primera edición, en sus dos primeros capítulos tratan sobre los fundamentos de los sistemas de control y el modelamiento de los sistemas eléctrico, mecánicos y electromecánicos

Free-standing faradaic motors based on biocompatible nanoperforated poly(lactic acid) layers and electropolymerized poly(3,4-ethylenedioxythiophene)

The electro-chemo-mechanical response of robust and flexible free-standing films made of three nanoperforated poly(lactic acid) (pPLA) layers separated by two anodically polymerized poly(3,4-ethylenedioxythiophene) (PEDOT) layers has been demonstrated. The mechanical and electrochemical properties of these films, which are provided by pPLA and PEDOT, respectively, have been studied by nanoindentation, cyclic voltammetry, and galvanostatic charge–discharge assays. The unprecedented combination of properties obtained for this system is appropriated for its utilization as a Faradaic motor, also named artificial muscle. Application of square potential waves has shown important bending movements in the films, which can be repeated for more than 500 cycles without damaging its mechanical integrity. Furthermore, the actuator is able to push a huge amount of mass, as it has been proved by increasing the mass of the passive pPLA up to 328% while keeping the mass of electroactive PEDOT unaltered.Peer ReviewedPostprint (author's final draft

CLASP Constraints on the Magnetization and Geometrical Complexity of the Chromosphere-Corona Transition Region

The Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP) is a suborbital rocket experiment that on 3rd September 2015 measured the linear polarization produced by scattering processes in the hydrogen Ly-$\alpha$ line of the solar disk radiation, whose line-center photons stem from the chromosphere-corona transition region (TR). These unprecedented spectropolarimetric observations revealed an interesting surprise, namely that there is practically no center-to-limb variation (CLV) in the $Q/I$ line-center signals. Using an analytical model, we first show that the geometrical complexity of the corrugated surface that delineates the TR has a crucial impact on the CLV of the $Q/I$ and $U/I$ line-center signals. Secondly, we introduce a statistical description of the solar atmosphere based on a three-dimensional (3D) model derived from a state-of-the-art radiation magneto-hydrodynamic simulation. Each realization of the statistical ensemble is a 3D model characterized by a given degree of magnetization and corrugation of the TR, and for each such realization we solve the full 3D radiative transfer problem taking into account the impact of the CLASP instrument degradation on the calculated polarization signals. Finally, we apply the statistical inference method presented in a previous paper to show that the TR of the 3D model that produces the best agreement with the CLASP observations has a relatively weak magnetic field and a relatively high degree of corrugation. We emphasize that a suitable way to validate or refute numerical models of the upper solar chromosphere is by confronting calculations and observations of the scattering polarization in ultraviolet lines sensitive to the Hanle effect.Comment: Accepted for publication in The Astrophysical Journal Letter

SopB promotes phosphatidylinositol 3-phosphate formation on Salmonella vacuoles by recruiting Rab5 and Vps34

Salmonella colonizes a vacuolar niche in host cells during infection. Maturation of the Salmonella-containing vacuole (SCV) involves the formation of phosphatidylinositol 3-phosphate (PI(3)P) on its outer leaflet. SopB, a bacterial virulence factor with phosphoinositide phosphatase activity, was proposed to generate PI(3)P by dephosphorylating PI(3,4)P2, PI(3,5)P2, and PI(3,4,5)P3. Here, we examine the mechanism of PI(3)P formation during Salmonella infection. SopB is required to form PI(3,4)P2/PI(3,4,5)P3 at invasion ruffles and PI(3)P on nascent SCVs. However, we uncouple these events experimentally and reveal that SopB does not dephosphorylate PI(3,4)P2/PI(3,4,5)P3 to produce PI(3)P. Instead, the phosphatase activity of SopB is required for Rab5 recruitment to the SCV. Vps34, a PI3-kinase that associates with active Rab5, is responsible for PI(3)P formation on SCVs. Therefore, SopB mediates PI(3)P production on the SCV indirectly through recruitment of Rab5 and its effector Vps34. These findings reveal a link between phosphoinositide phosphatase activity and the recruitment of Rab5 to phagosomes

Anthelmintic effect of Pterogyne nitens (Fabaceae) on eggs and larvae of Haemonchus contortus: analyses of structure-activity relationships based on phenolic compounds.

Due to high prevalence and large pathogenicity, Haemonchus contortus is the main gastrointestinal nematode in tropical and subtropical regions. This species is responsible for severe economic losses to sheep and goat breeders in Brazil. The control of this parasite is currently compromised, mainly, due to anthelmintic resistance. In the search for natural anthelmintic alternatives, Pterogyne nitens, a native Brazilian tree with potential ethnopharmacological activity, has been identified. The aim of this study was to evaluate the anthelmintic activity of ethanolic extracts and phenolic compounds from P. nitens, as well as two commercial flavonoids (chrysin and morin), to derive the chemical structure and anthelmintic activity. The ovicidal and larvicidal activity of ethanolic extracts from leaves (EEL) and fruits (EEFR), as well as natural compounds from P. nitens on H. contortus were evaluated through egg hatch assay (EHA) and larval development assay (LDA). The results showed that all extracts, especially the phenolic compounds were active in the EHA and LDA. The egg hatch inhibitory effects of EEL (EC50 = 316 &#956;g/mL) were more potent than EEFR (EC50 = 512 &#956;g/mL). However, larval development inhibitory effects of EEL (EC50 = 47 &#956;g/mL) and EEFR (EC50 = 35 &#956;g/mL) were similar. Among the compounds, the flavones (sorbifolin, pedalitin, and chrysin) did not have inhibitory effects on egg hatching but presented some activity against larval development of H. contortus. In contrast, the flavonols (quercetin, rutin, and morin) showed high activity in the EHA but were inactive in the LDA. The addition of at hydroxyl group and rutinose group to the flavonoid structure increased the ovicidal and larvicidal activity, respectively. The phenolic acids showed potent anthelmintic activity: caffeic acid, ferulic acid, and gallic acid had the highest anthelmintic effects, presenting EC50 values of 1.48, 0.56, and 4.93 &#956;g/mL in the EHA; and 31, 22, and 33 &#956;g/mL in the LDA, respectively. These results suggest that P. nitens might be a source of effective alternative compounds to control H. contortus

Otimização do teste de desenvolvimento larvar para o monitoramento da resistência anti-helmíntica.

A validação de ferramentas laboratoriais para o diagnóstico da resistência parasitária em rebanhos é extremamente importante