Posttransplantation diabetes mellitus after liver transplant and the impact of family history of diabetes in a Mexican cohort.

INTRODUCTION AND AIMS: Posttransplantation diabetes mellitus (PTDM) is a serious long-term complication that has a negative impact on graft and patient survival. The purpose of the present study was to describe the incidence of PTDM in a Mexican cohort and evaluate its association with a previous family history of diabetes (FHD). METHODS: A retrospective single-center cohort study was conducted on patients undergoing liver transplantation (LT). The primary outcome was time from LT to PTDM. The diagnosis of PTDM was established using the ADA criteria. A mediation analysis that used adjusted Cox regression models and considered pretransplant prediabetes a mediator was performed, to determine the total effect and direct effect of FHD on PTDM. RESULTS: A total of 152 patients were included, with a median follow-up time of 41 months; 19.2% (n = 29) had pretransplant diabetes. During the follow-up time, 15% of patients developed PTDM (n = 23), with an incidence rate of 4.71 cases/100 person-years. PTDM was significantly higher in patients with FHD, compared with those with no FHD (8.72 cases/100 person-years vs 2.04 cases/100 person-years, respectively; p = 0.001). The adjusted hazard ratio of PTDM for FHD was 4.14 (95% CI 1.60-10.7), p = 0.005) and 3.48 (95% CI 1.35-9.01, p = 0.010), when further controlled for pretransplant prediabetes. CONCLUSION: The occurrence of PTDM was similar to that reported in most international studies. As with type 2 diabetes, family history plays an important role in the development of PTDM, even after accounting for pretransplant prediabetes. Patients with FHD should undergo a stricter metabolic program.

Current vision on diagnosis and comprehensive care in hepatic encephalopathy.

The first clinical guidelines on hepatic encephalopathy were published in 2009. Almost 14 years since that first publication, numerous advances in the field of diagnosis, treatment, and special condition care have been made. Therefore, as an initiative of the Asociación Mexicana de Gastroenterología A.C., we present a current view of those aspects. The manuscript described herein was formulated by 24 experts that participated in six working groups, analyzing, discussing, and summarizing the following topics: Definition of hepatic encephalopathy; recommended classifications; epidemiologic panorama, worldwide and in Mexico; diagnostic tools; conditions that merit a differential diagnosis; treatment; and primary and secondary prophylaxis. Likewise, these guidelines emphasize the management of certain special conditions, such as hepatic encephalopathy in acute liver failure and acute-on-chronic liver failure, as well as specific care in patients with hepatic encephalopathy, such as the use of medications and types of sedation, describing those that are permitted or recommended, and those that are not.

Approach to the patient with cholestasis and jaundice syndrome. Joint AMH, AMG, and AMEG scientific position statement.

The term cholestasis refers to bile acid retention, whether within the hepatocyte or in the bile ducts of any caliber. Biochemically, it is defined by a level of alkaline phosphatase that is 1.67-times higher than the upper limit of normal. Cholestatic diseases can be associated with an inflammatory process of the liver that destroys hepatocytes (hepatitis), withjaundice (yellowing of the skin and mucus membranes, associated with elevated serum bilirubin levels), or with both, albeit the three concepts should not be considered synonymous. Cholestatic diseases can be classified as intrahepatic or extrahepatic, depending on their etiology. Knowing the cause of the condition is important for choosing the adequate diagnostic studies and appropriate treatment in each case. A complete medical history, together with a thorough physical examination and basic initial studies, such as liver ultrasound and liver function tests, aid the clinician in deciding which path to follow, when managing the patient with cholestasis. In a joint effort, the Asociación Mexicana de Hepatología (AMH), the Asociación Mexicana de Gastroenterología (AMG) and the Asociación Mexicana de Endoscopia Gastrointestinal (AMEG) developed the first Mexican scientific position statement on said theme.

Diagnosis of multiple sclerosis using multifocal ERG data feature fusion.

The purpose of this paper is to implement a computer-aided diagnosis (CAD) system for multiple sclerosis (MS) based on analysing the outer retina as assessed by multifocal electroretinograms (mfERGs). MfERG recordings taken with the RETI-port/scan 21 (Roland Consult) device from 15 eyes of patients diagnosed with incipient relapsing-remitting MS and without prior optic neuritis, and from 6 eyes of control subjects, are selected. The mfERG recordings are grouped (whole macular visual field, five rings, and four quadrants). For each group, the correlation with a normative database of adaptively filtered signals, based on empirical model decomposition (EMD) and three features from the continuous wavelet transform (CWT) domain, are obtained. Of the initial 40 features, the 4 most relevant are selected in two stages: a) using a filter method and b) using a wrapper-feature selection method. The Support Vector Machine (SVM) is used as a classifier. With the optimal CAD configuration, a Matthews correlation coefficient value of 0.89 (accuracy = 0.95, specificity = 1.0 and sensitivity = 0.93) is obtained. This study identified an outer retina dysfunction in patients with recent MS by analysing the outer retina responses in the mfERG and employing an SVM as a classifier. In conclusion, a promising new electrophysiological-biomarker method based on feature fusion for MS diagnosis was identified.

Asociación Mexicana de Hepatología A.C. Clinical guideline on hepatitis B.

Hepatitis B virus (HBV) infection continues to be a worldwide public health problem. In Mexico, at least three million adults are estimated to have acquired hepatitis B (total hepatitis B core antibody [anti-HBc]-positive), and of those, 300,000 active carriers (hepatitis B surface antigen [HBsAg]-positive) could require treatment. Because HBV is preventable through vaccination, its universal application should be emphasized. HBV infection is a major risk factor for developing hepatocellular carcinoma. Semi-annual liver ultrasound and serum alpha-fetoprotein testing favor early detection of that cancer and should be carried out in all patients with chronic HBV infection, regardless of the presence of advanced fibrosis or cirrhosis. Currently, nucleoside/nucleotide analogues that have a high barrier to resistance are the first-line therapies.

Asociación Mexicana de Hepatología A.C. Clinical guideline on hepatitis B. / Asociación Mexicana de Hepatología A.C. Guía Clínica de Hepatitis B.

Hepatitis B virus (HBV) infection continues to be a worldwide public health problem. In Mexico, at least three million adults are estimated to have acquired hepatitis B (total hepatitis B core antibody [anti-HBc]-positive), and of those, 300,000 active carriers (hepatitis B surface antigen [HBsAg]-positive) could require treatment. Because HBV is preventable through vaccination, its universal application should be emphasized. HBV infection is a major risk factor for developing hepatocellular carcinoma. Semi-annual liver ultrasound and serum alpha-fetoprotein testing favor early detection of that cancer and should be carried out in all patients with chronic HBV infection, regardless of the presence of advanced fibrosis or cirrhosis. Currently, nucleoside/nucleotide analogues that have a high barrier to resistance are the first-line therapies.

Accurate method for rapid biomass quantification based on specific absorbance of microalgae species with biofuel importance.

The development of microalgae culture technology has been an integral part to produce biomass feedstock to biofuel production. Due to this, numerous attempts have been made to improve some operational parameters of microalgae production. Despite this, specialized research in cell growth monitoring, considered as a fundamental parameter to achieve profitable applications of microalgae for biofuels production, presents some opportunity areas mainly related to the development of specific and accurate methodologies for growth monitoring. In this work, predictive models were developed through statistical tools that correlate a specific micro-algal absorbance with cell density measured by cell count (cells∙per ml), for three species of interest for biofuels production. The results allow the precise prediction of cell density through a logistic model based on spectrophotometry, valid for all the kinetics analysed. The adjusted determination coefficients ( r adj 2 ) for the developed models were 0·993, 0·995 and 0·994 for Dunaliella tertiolecta, Nannochloropsis oculata and Chaetoceros muelleri respectively. The results showed that the equations obtained here can be used with an extremely low error (≤2%) for all the cell growth ranges analysed, with low operational cost and high potential of automation. Finally, a user-friendly software was designed to give practical use to the developed predictive models.

Psychosocial evaluation for liver transplantation: A brief guide for gastroenterologists. / Evaluación psicosocial para trasplante hepático: una guía breve para gastroenterólogos.

Liver transplantation is a lifesaving treatment that improves survival and quality of life. The procedure requires adequate transplant candidate selection carried out by a multidisciplinary team. Psychosocial evaluation is a necessary part of recipient selection and its primary aims are to identify problems and psychosocial needs of the patient and his/her family, to improve transplantation outcomes. Different psychosocial conditions are considered risk factors for morbidity and mortality after transplantation. The presence of those factors per se is not an absolute contraindication, thus adequate evaluation promotes equal access to healthcare, improves results, and optimizes resources. The present review provides an overview of and guidelines for the most important psychosocial issues during the pretransplantation phase.

Hemophagocytic syndrome following alemtuzumab treatment for multiple sclerosis: A case report.

BACKGROUND: Alemtuzumab is a monoclonal antibody targeting CD-52, used for treating relapsing-remitting multiple sclerosis (RRMS). METHODS: We present a case of a 44-year-old male with RRMS who was admitted due to fever and jaundice after starting treatment with alemtuzumab 12 months ago. RESULTS: He was diagnosed with hemophagocytic syndrome (HS). Liver biopsy revealed images of hemophagocytosis in Kupffer cells of lobular sinusoid. Management consisted of treatment with corticosteroids. CONCLUSION: HS is a severe condition marked by an excessive activation of the immune system that leads to a rapid and progressive multi-organ failure, so it is important to consider it in the differential diagnosis of a fever syndrome following the administration of alemtuzumab.

Diagnostic ability of multifocal electroretinogram in early multiple sclerosis using a new signal analysis method.

PURPOSE: To determine if a novel analysis method will increase the diagnostic value of the multifocal electroretinogram (mfERG) in diagnosing early-stage multiple sclerosis (MS). METHODS: We studied the mfERG signals of OD (Oculus Dexter) eyes of fifteen patients diagnosed with early-stage MS (in all cases < 12 months) and without a history of optic neuritis (ON) (F:M = 11:4), and those of six controls (F:M = 3:3). We obtained values of amplitude and latency of N1 and P1 waves, and a method to assess normalized root-mean-square error (FNRMSE) between model signals and mfERG recordings was used. Responses of each eye were analysed at a global level, and by rings, quadrants and hemispheres. AUC (area under the ROC curve) is used as discriminant factor. RESULTS: The standard method of analysis obtains further discrimination between controls and MS in ring R3 (AUC = 0.82), analysing N1 waves amplitudes. In all of the retina analysis regions, FNRMSE value shows a greater discriminating power than the standard method. The highest AUC value (AUC = 0.91) was in the superior temporal quadrant. CONCLUSION: By analysing mfERG recordings and contrasting them with those of healthy controls it is possible to detect early-stage MS in patients without a previous history of ON.

The Mexican consensus on nonalcoholic fatty liver disease. / Consenso mexicano de la enfermedad por hígado graso no alcohólico.

Nonalcoholic fatty liver disease (NAFLD) affects nearly one third of the population worldwide. Mexico is one of the countries whose population has several risk factors for the disease and its prevalence could surpass 50%. If immediate action is not taken to counteract what is now considered a national health problem, the medium-term panorama will be very bleak. This serious situation prompted the Asociación Mexicana de Gastroenterología and the Asociación Mexicana de Hepatología to produce the Mexican Consensus on Fatty Liver Disease. It is an up-to-date and detailed review of the epidemiology, pathophysiology, clinical forms, diagnosis, and treatment of the disease, whose aim is to provide the Mexican physician with a useful tool for the prevention and management of nonalcoholic fatty liver disease.

Coding Prony's method in MATLAB and applying it to biomedical signal filtering.

BACKGROUND: The response of many biomedical systems can be modelled using a linear combination of damped exponential functions. The approximation parameters, based on equally spaced samples, can be obtained using Prony's method and its variants (e.g. the matrix pencil method). This paper provides a tutorial on the main polynomial Prony and matrix pencil methods and their implementation in MATLAB and analyses how they perform with synthetic and multifocal visual-evoked potential (mfVEP) signals. This paper briefly describes the theoretical basis of four polynomial Prony approximation methods: classic, least squares (LS), total least squares (TLS) and matrix pencil method (MPM). In each of these cases, implementation uses general MATLAB functions. The features of the various options are tested by approximating a set of synthetic mathematical functions and evaluating filtering performance in the Prony domain when applied to mfVEP signals to improve diagnosis of patients with multiple sclerosis (MS). RESULTS: The code implemented does not achieve 100%-correct signal approximation and, of the methods tested, LS and MPM perform best. When filtering mfVEP records in the Prony domain, the value of the area under the receiver-operating-characteristic (ROC) curve is 0.7055 compared with 0.6538 obtained with the usual filtering method used for this type of signal (discrete Fourier transform low-pass filter with a cut-off frequency of 35 Hz). CONCLUSIONS: This paper reviews Prony's method in relation to signal filtering and approximation, provides the MATLAB code needed to implement the classic, LS, TLS and MPM methods, and tests their performance in biomedical signal filtering and function approximation. It emphasizes the importance of improving the computational methods used to implement the various methods described above.

El uso de marcadores discursivos en la producción lingüística de un paciente con afasia motora aferente / Use of discourse markers in linguistic production of one speaker with afferent motor aphasia

En este trabajo se analiza el uso y las funciones de los marcadores discursivos en la producción de un paciente con afasia motora aferente. Se analiza un corpus proveniente de una entrevista semiestructurada realizada durante la terapia neuropsicológica. El objetivo es analizar cualitativamente el uso de los marcadores discursivos y las funciones que desempeñan a lo largo de las intervenciones del paciente. Se busca mostrar que los marcadores discursivos se conservan en este tipo de afasia porque funcionan como estrategias compensatorias que facilitan la comunicación del paciente y responden a los déficits particulares de la afasia motora aferente. El análisis de los datos muestra que el paciente emplea consistentemente cuatro tipos de marcadores discursivos: (i) conectores, (ii) reformuladores, (iii) formuladores y (iv) modalizadores, a pesar del déficit lingüístico que padece. Esto sugiere que los marcadores desempeñan funciones específicas que contribuyen a subsanar los problemas a los que se enfrenta el paciente durante la construcción de su intervención. Este hecho resulta consistente con los resultados previos obtenidos en otras variedades de afasia. Finalmente, esto contribuye a la idea de que en la afasia el nivel pragmático-discursivo sufre una desintegración menos drástica si se le compara con el nivel fonético-fonológico o el sintáctico

This paper analyzes use and functions of discourse markers in linguistic production of one speaker with afferent motor aphasia. A semi-structured interview carried out during neuropsychological therapy was analyzed. The aim of this study is to qualitatively analyze the use of discourse markers and the functions they perform in patient interventions. It attempts to show discourse markers are conserved in this type of aphasia because they perform as compensatory strategies which make patient communication easier and respond to the particular deficits which characterize this aphasia. Data analysis shows that the patient consistently uses four kinds of markers: (i) connectors, (ii) reformulators, (iii) formulators, and (iv) modalizers, despite pathology. This suggests that discourse markers perform specific functions which help to resolve the problems which the patient faces during construction of his intervention. This fact is consistent with the results obtained in previous studies with other aphasia varieties. Finally, this contributes to the notion that, in aphasia, pragmatic and discursive levels suffer a less drastic disintegration than that of the phonetic-phonological level orthe syntactic level

Brief Test of Attention: Normative data for the Latin American Spanish speaking adult population.

OBJECTIVE: To generate normative data on the Brief Test of Attention (BTA) across 11 countries in Latin America, with country-specific adjustments for gender, age, and education, where appropriate. METHOD: The sample consisted of 3,977 healthy adults who were recruited from Mexico, Argentina, Peru, Paraguay, Honduras, Chile, Cuba, Puerto Rico, Guatemala, El Salvador, and Bolivia. Each subject was administered the BTA as part of a larger neuropsychological battery. A standardized five-step statistical procedure was used to generate the norms. RESULTS: The final multiple linear regression models explained between 11-41% of the variance in BTA scores. Although men had higher scores on the BTA in Honduras, there were no other significant gender differences, and this one effect size was small. As a result, gender-adjusted norms were not generated. CONCLUSIONS: This is the first normative multicenter study conducted in Latin America to create norms for the BTA; this study will have an impact on the future practice of neuropsychology throughout Latin America.

ZnO-based dye solar cell with pure ionic-liquid electrolyte and organic sensitizer: the relevance of the dye­oxide interaction in an ionic-liquid medium.

The use of non-volatile electrolytes and fully organic dyes are key issues in the development of stable dye-sensitized solar cells (DSCs). In this work we explore the performance of ZnO-based DSCs sensitized with an indoline derivative coded D149 in the presence of a pure ionic-liquid electrolyte. Commercial nanostructured zinc oxide and an electrolyte composed of iodine plus (1) pure 1-propyl-3-methyl imidazolium iodide (PMII) and (2) a blend of PMII with low-viscosity ionic liquids were employed to construct the devices. Without further additives, the fabricated devices exhibit remarkable short-circuit photocurrents and efficiencies under AM1.5 simulated sunlight (up to 10.6 mA cm−2, 2.9% efficiency, 1 sun, active area = 0.64 cm2) due to the high surface area of the ZnO film and the high absorptivity of the D149 dye. Impedance spectroscopy is used to characterize the devices. It is found that the addition of the low-viscosity ionic-liquid improves the transport features (leading to a better photocurrent) but it does not alter the recombination rate. The robustness of the dye­oxide interaction is tested by applying continuous illumination with a Xenon-lamp. It is observed that the photocurrent is reduced at a slow rate due to desorption of the D149 sensitizer in the presence of the ionic liquid. Exploration of alternative ionic-liquid compositions or modification of the ZnO surface is therefore required to make stable devices based on ZnO and fully organic dyes.

Agentes etiológicos de uretritis infecciosa masculina en pacientes que concurren a laboratorios de Asunción / Etiological aspects o male infectious urethritis in patients attending laboratories of Asuncion

Esta investigación se efectuó para ampliar el conocimiento sobre los agentes etiológicos de la uretritis masculina en Asunción; se basó en una revisión retrospectiva de las fichas clínicas de 619 pacientes que acudieron con propósitos diagnósticos a tres laboratorios privados y a un laboratorio público de Asunción. La edad promedio ± DE fue de37,6±15,2 años (rango 0-91 años), 373 pacientes concurrieron a Meyer Lab, 166 al laboratorio San Roque, 68 al laboratorio de Santa Clara y 12 al laboratorio de Microbiología del IICS. En total se procesaron muestras de orina de 289 pacientes, secreción uretral de 326 y en 4 pacientes tanto orina como secreción uretral. Las indicaciones médicas fueron búsqueda de Neisseria gonorrhoeae en 295 pacientes, Chlamydia trachomatis en 256, Ureaplasma urealyticum en 264, Mycoplasma hominis en199. Se demostró la presencia de N. gonorrhoeae en el 6,4% de los casos, C. trachomatisen el 3,5%, U. urealyticum 11,5% y M. hominis 2,5%. A pesar de que se halló un franco predominio de la forma no gonocóccica, considerando las limitaciones que tiene el estudio por su carácter retrospectivo, es necesario realizar estudios prospectivos con mayor número de muestras para establecer con certeza la prevalencia de los agentes etiológicosde las uretritis infecciosas en el varón, incluyendo búsqueda de otros agentes infecciosos. Es necesario disponer de datos sobre uretritis en otros grupos socio económicos e investigar aspectos como la frecuencia en nuestro medio del síndrome de uretritis postgonocóccica (UPG) y de cepas de N. gonorrhoeae productoras de β lactamasa.

This study was carried out in order to contribute to the knowledge of the etiological agents of male urethritis in Asunción. It is based on a retrospective review of clinical records of 619 patients from one public and three private laboratories in Asunción. Theage mean ± SD was 37.6 ± 15.2 years (range 0-91 years); 373 patients were from Meyer Lab, 166 from San Roque Laboratory, 68 from Santa Clara Laboratory and twelve from the Laboratory of Microbiology of the IICS. Urine samples from 289 patients, urethra secretion from 326 and both types of samples from 4 patients were studied. Diagnosis of Neisseria gonorrhoeae was requested for 295 patients, Chlamydia trachomatis for 256,Ureaplasma urealyticum for 264, Mycoplasma hominis for 199. Presence of N. gonorrhoeae was demonstrated in 6.4% of the cases, C. trachomatis in 3.5%, U. urealyticum in 11.5% and M. hominis in 2.5%. Even though there was a clear predominance of non-gonococcal urethritis, considering the limitation of this study due to its retrospective nature, prospective studies with larger samples are necessary toestablish with certainty the prevalence of the etiological agents of male infectious urethritis, including the search of other infectious agents. It is also necessary to have data about urethritis in other socioeconomic groups and investigate aspects such as thefrequency of post-gonococcal urethritis syndrome (PGU) and beta-lactamase producing N. Gonorrhoeae strains in our area.

Escleroterapia con espuma densa de varices quirúrgicas / Sclerotherapy with dense foam of surgical varicose veins

La escleroterapia de varices cuyo uso se remonta a 1853, es una técnica muy usada en todo el mundo para el tratamiento de las varices. Objetivo de nuestro trabajo es evaluar la efectividad del tratamiento esclerosante con espuma densa de varices quirúrgicas. Se realizo un estudio descriptivo, prospectivo de corte transversal con el fin de evaluar la eficacia de la escleroterapia con espuma densa en pacientes con síndrome varicoso tributario de tratamiento quirúrgico atendido en consulta externa del policlico “Darío Calzadilla Angulo” en Banes durante el año 2008. El universo estuvo constituido por un total de 12 pacientes 10 del sexo femenino y 2 del sexo masculino que presentaban varices que debían ser operados como tratamiento definitivo. El sexo femenino predominó, en el rango de grupo de edad de 40-50 años con 6 pacientes (60%) y 2 del sexo masculino que también estuvo en este rango de edad. El síntoma fundamental que presentaban los pacientes, fue la sensación de pesadez en miembros inferiores (66.6%). La complicación que predominando con este tratamiento fue la pigmentación de la piel con2 (16.6%). El grado de satisfacción de los pacientes fue de (91.6%) 11 pacientes de los 12 atendidos, se recoge 1 paciente que no continuó el tratamiento por haber sufrido necrosis de la piel a nivel de la puntura (AU)

The sclerotherapy of varixes whose use goes back at 1853, is a technique very used in the entire world for the treatment ofthe varixes. Objective of our work is to evaluate the effectiveness of the treatment sclerosant with dense foam of surgical varixes. We carries out a study descriptive, prospective of traverse court with the purpose of evaluating the effectiveness of thesclero therapy with dense foam in patient with tributary varicose of surgical treatment assisted in external consultation of the policlinic “Darío Calzadilla Ángulo” during the year 2008. The universe was constituted by a total of 12 patients 10 of the feminine sex and 2 of the masculine sex that presented varixes that should be surgical as definitive treatment. The feminine sex prevailed, in the range of group of 40-50 year-old age with 6 patients (60%) and 2 of the masculine sex that it was also in this age range. The main symptom that the patients presented, was the sensation of heaviness in inferior members (66.6%). The complication that prevailing with this treatment was the pigmentation of the skin with 2 (16.6%). The degree of the patients' satisfaction was of (91.6%) assisted 11 patients of the 12, 1 patient is picked up that the treatment didn't continue to have suffered necrosis from the skin to level of the puncture (AU)