Enterobacteriaceae in the Human Gut: Dynamics and Ecological Roles in Health and Disease.

The human gut microbiota plays a crucial role in maintaining host health. Our review explores the prevalence and dynamics of Enterobacteriaceae, a bacterial family within the Proteobacteria phylum, in the human gut which represents a small fraction of the gut microbiota in healthy conditions. Even though their roles are not yet fully understood, Enterobacteriaceae and especially Escherichia coli (E. coli) play a part in creating an anaerobic environment, producing vitamins and protecting against pathogenic infections. The composition and residency of E. coli strains in the gut fluctuate among individuals and is influenced by many factors such as geography, diet and health. Dysbiosis, characterized by alterations in the microbial composition of the gut microbiota, is associated with various diseases, including obesity, inflammatory bowel diseases and metabolic disorders. A consistent pattern in dysbiosis is the expansion of Proteobacteria, particularly Enterobacteriaceae, which has been proposed as a potential marker for intestinal and extra-intestinal inflammatory diseases. Here we develop the potential mechanisms contributing to Enterobacteriaceae proliferation during dysbiosis, including changes in oxygen levels, alterations in mucosal substrates and dietary factors. Better knowledge of these mechanisms is important for developing strategies to restore a balanced gut microbiota and reduce the negative consequences of the Enterobacteriaceae bloom.

Design and validation of a dual-fluorescence reporter system to monitor bacterial gene expression in the gut environment.

Fluorescence-based reporter systems are valuable tools for studying gene expression dynamics in living cells. However, available strategies to follow gene expression in bacteria within their natural ecosystem that can be typically rich and complex are scarce. In this work, we designed a plasmid-based tool ensuring both the identification of a strain of interest in complex environments and the monitoring of gene expression through the combination of two distinct fluorescent proteins as reporter genes. The tool was validated in Escherichia coli to monitor the expression of eut genes involved in the catabolism of ethanolamine. We demonstrated that the constructed reporter strain gradually responds with a bimodal output to increasing ethanolamine concentrations during in vitro cultures. The reporter strain was next inoculated to mice, and flow cytometry was used to detect the reporter strain among the dense microbiota of intestinal samples and to analyze specifically the expression of eut genes. This novel dual-fluorescent reporter system would be helpful to evaluate transcriptional processes in bacteria within complex environments. KEY POINTS: • A reporter tool was developed to monitor bacterial gene expression in complex environments. • Ethanolamine utilization (eut) genes are expressed by commensal E. coli in the mouse gut. • Expression of eut genes follows a bimodal distribution.

Diversity of ethanolamine utilization by human commensal Escherichiacoli.

Ethanolamine (EA) is a substrate naturally present in the human gut and its catabolism by bacteria relies on the presence of eut genes encoding specific metabolic enzymes and accessory proteins. To date, EA utilization has been mostly investigated in gut bacterial pathogens. The aim of this study was to evaluate the ability of human gut commensal Escherichia coli isolates to utilize EA as a nitrogen and/or carbon sources. Although the capacity to consume EA is heterogeneous between the 40 strains of our collection, we determined that most of them could degrade EA to generate ammonia, a useful nitrogen resource for growth. Three isolates were also able to exploit EA as a carbon source. We also revealed that the inability of some strains to catabolize EA is explained either by mutations in the eut locus or by a defect in gene transcription. Finally, we demonstrated the importance of EA utilization for an optimal fitness of commensal E. coli in vivo. Our study provides new insights on the diversity of commensal E. coli strains to utilize EA as a nutrient in the gut and opens the way for new research in the field of interactions between host, gut microbiota and pathogens.

Objective computerized evaluation of normal patterns of facial muscles contraction.

UNLABELLED: Different methods used to evaluate the movements of the face have many degrees of subjectivity and reliability. The authors discuss the ease of using these methods in clinical practice or their accuracy in scientific research. AIM: To obtain the standard for normal facial muscles movements using an objective method - the Vicon system. MATERIALS AND METHODS: Light reflective markers were placed at points of interest on the face of 12 normal subjects. The movements were captured by cameras that sent the images to a computer. The points' displacements were measured between rest and maximum muscle contraction; and we calculated the means and the standard deviations (SD) were calculated. RESULTS: When smiling, the variation of the oral commissures was between 6.45 and 12.11 mm, mean of 9.28 mm and SD od 2.83; for lifting the eyebrow, it is between 6.0 and 13.08 mm, mean of 10.57 mm and SD of 2.51; for eyelids movement there was a variation of 6.89 and 11.29 mm, with a mean value of 9.09 mm and SD of 2.20; for the movement of wrinkling the forehead, the results showed a variation of 4.16 and 10.85 mm, with a mean value of 7.56 and SD of 3.29. CONCLUSION: The authors obtained normal patterns for facial muscle contraction.

Encefalocele occipital: reporte de un caso / Occipital encephalocele: a case report

Presentamos el caso de un recién nacido femenino, con encefalocele occipital, diagnosticado en el período perinatal a las 29 semanas de gestación; atendido en los Servicios de Obstetricia y Neurocirugía del Hospital Universitario de Caracas. Se realizó una revisión la literatura dada la poca frecuencia de esta patología

We presente a case of female newborn child with occipital encephalocele diagnosed at 29 weeks of pregnancy; being attended in the Service of Obstetrics and Neurosurgery of the Hospital Universitario de Caracas. A literature review was done by infrecuent pathology

Síndrome de Kawasaki: enfoque clínico integral en cuatro centros del área Metropolitana de Caracas / Kawasaki syndrome: integral clinical and therapeutic approach in four Hospitals in Caracas Venezuela

El síndrome Kawasaki (SK) es una vasculitis sistémica que carece de pruebas diagnósticas. Retrasos en el diagnóstico y tratamiento pueden ocasionar dilataciones de las arterias coronarias (DAC). Evaluar las características demográficas, criterios diagnósticos, órganos afectados, alteraciones de laboratorio, tratamiento y compromiso cardiovascular, en niños hospitalizados cos SK, en cuatro centros hospitalarios del área Metropolitana de Caracas. Se revisaron las historias de niños de 1 mes a 12 años con diagnóstico de SK, hospitalizados entre enero 2001-diciembre 2004 en los hospitales J. M. de Los Ríos, "Miguel Pérez Carreño". Elías Toro y universitario de Caracas. Un total d 28 niños cumplieron criterios diagnósticos de SK el 71% fueron varones. La edad promedio fue de 2,12 años. El 60% de los diagnósticos fueron tardíos. El 50% presentó afección cardiovascular y el 37,5% DAC. Cifras de velocidad de sedimentación globular ó de proteina C reactiva más elevadas al ingreso y la administración de inmunoglubina intravenosa (IGIV) tardíamente, se asociaron con un mayor riesgo para desarrollar DAC (p<0,05). La mayoría de los pacientes presentaron diagnósticos tardío por manifestaciones incompletas de la enfermedad, errores diagnósticos o consulta tardía. Este resultado se asoció notoriamente con el elevado porcentaje de manifestaciones cardiacas. Cifras elevadas de VSG ó PCR al ingreso y la administración tardía de IGIV, se asociaron con mayor frecuencia de DAC. Se considera importante incentivar a los médicos en el conocimiento de esta patología y en los diagnósticos diferenciales. El diagnóstico y tratamiento precoz y las consultas de seguimiento son fundamentales.

Estudio controlado de polimaltosato férrico (IPC) y proteína férrica (F o ferritina) en niños con anemia ferropénica / Study controlled of ferric polimaltose and ferric protein in chlidren with iron deficiency anemia

Debido a que tanto el déficit de hierro como la anemia ferropénica constituyen un grave problema de salud en niños, y asimismo, considerando que hasta el presente no se han realizado estudios randomizados-controlados con IPC y F, se diseñó un ensayo clínico para determinar la rapidez y la efectividad de la respuesta a dichos fármacos, después de tres meses de tratamiento, en niños entre 6 meses a 6 años. A todos los pacientes se les administró hierro a la dosis 5 mg/Kg de peso/día: previa aprobación de los comités de ética y consentimiento escrito del representante, se administró hierro A (posteriormente identificado como IPC) o hierro B (posteriormente identificado como F) a 41 niños con el diagnóstico clínico y de laboratorio de anemia feropénica (Hb 7-10 g/dL; VCM<70 fL; HS<30 mcg/dL; FS<10 mcg/dL; por ciento ST<10), de acuerdo con los criterios de inclusión y exclusión. Se retiraron 8 pacientes por presentar patologías o recibir tratamientos que pudieron modificar la respuesta. Población : hembras 15, varones 18. Edad de 6 a 24 meses: 84.85 por ciento y de 25 a 72 meses: 15.15 por ciento. Finalmente, terminaron el estudio 33 pacientes (un paciente adicional se incluyó en el grupo F para el análisis de seguridad, pero no para la evaluación de eficacia ya que se retiró por posible evento adverso a la 7ma semana). Los resultados sugieren que con ambas terapias se obtiene una rápida y significativa respuesta hematológica, tanto a las 3 semanas como a los 3 meses del tratamiento, en pacientes pediátricos con anemia ferropénica sin patologías asociadas. Sin embargo, se observa que al final del estudio, en el grupo IPC hubo una mejor recuperación del metabolismo de hierro de la ferritina sérica. En relación con la seguridad del tratamiento, 3 pacientes (17,64 por ciento) en el grupo F presenatron efectos secundarios, lo cual no observó en el grupo IPC