Escherichia coli productora de toxina Shiga: el desafío de adherirse para sobrevivir / Shiga toxin producing Escherichia coli: the challenge of adherence to survive

Resumen Las cepas de Escherichia coli productoras de toxina Shiga (STEC) son reconocidas como responsables de un alto número de casos de enfermedades de transmisión alimentaria a nivel mundial. Su patogenicidad ha sido vinculada directamente con la actividad de las toxinas (Stx); sin embargo, la habilidad de estas bacterias para colonizar al huésped y otras superficies puede ser esencial para desarrollar su poder patogénico. La gran plasticidad genómica de cepas STEC se infiere de la variabilidad de perfiles de virulencia, con la frecuente emergencia de cepas con nuevos genes, codificados en nuevas islas de patogenicidad vinculadas al metabolismo y la adherencia. La formación de biofilm es un mecanismo espontáneo por el cual las cepas STEC resisten en un ambiente hostil, lo que les permite sobrevivir y, de esa forma, llegar al huésped, a través de los alimentos o de las superficies que están en contacto con ellos. Este mecanismo presenta una alta variabilidad intra e interserotipo y su desarrollo no depende solo de los microorganismos que lo conforman. Factores inherentes al ambiente (pH, temperatura) y la superficie (acero inoxidable, poliestireno) a la que pueden adherirse influyen en la expresión de biofilm. El concepto «una salud¼ implica la interrelación entre los actores de salud pública, animal y ambiental para lograr alimentos inocuos y evitar contaminación cruzada y resistencia a sanitizantes, lo cual pone de manifiesto la necesidad de identificar patógenos emergentes a través de nuevos marcadores moleculares, que detecten cepas STEC portadoras del denominado locus for enterocyte effacement (LEE) o del locus de adherencia y autoagregación (LAA).

Abstract Shiga Toxin-producing Escherichia coli (STEC) is recognized as being responsible for a large number of foodborne illnesses around the world. The pathogenicity of STEC has been related to Stx toxins. However, the ability of STEC to colonize the host and other surfaces can be essential for developing its pathogenicity. Different virulence profiles detected in STEC could cause the emergence of strains carrying new genes codified in new pathogenicity islands linked to metabolism and adherence. Biofilm formation is a spontaneous mechanism whereby STEC strains resist in a hostile environment being able to survive and consequently infect the host through contaminated food and food contact surfaces. Biofilm formation shows intra-and inter-serotype variability, and its formation does not depend only on the microorganisms involved. Other factors related to the environment (such as pH, temperature) and the surface (stainless steel and polystyrene) influence biofilm expression. The «One Health¼ concept implies the interrelation between public, animal, and environmental health actors to ensure food safety, prevent cross-contamination and resistance to sanitizers, highlighting the need to identify emerging pathogens through new molecular markers of rapid detection that involve STEC strains carrying the Locus of Enterocyte Effacement or Locus of Adhesion and Autoaggregation.

Resultados funcionales y complicaciones del uso del clavo cefalomedular en el tratamiento de las fracturas de cadera / Functional results and complications of the use of the proximal femoral nail in the treatment of intertrochanteric hip fractures

Resumen: Introducción: El clavo cefalomedular es utilizado para el tratamiento de la fractura de cadera; sin embargo, existen pocos estudios que permitan identificar datos sobre las complicaciones del uso de estos dispositivos y los resultados en términos de restauración de la funcionalidad del paciente. Métodos: Se realizó un estudio de corte transversal en pacientes con fractura de fémur durante el período de Enero de 2008 a Diciembre de 2012. Se recopiló información de variables demográficas y clínicas. Se llevó a cabo un seguimiento telefónico hasta seis meses postoperatorios. Se efectuó un análisis descriptivo utilizando medidas de frecuencia absolutas y relativas. Las variables cuantitativas se presentan con promedios y desviación estándar o mediana y rango intercuartil, según la normalidad de los datos. Resultados: De los pacientes, 82.9% logró caminar con o sin ayuda dentro de los seis meses posteriores a la cirugía. El tiempo de hospitalización fue de cuatro días en promedio; las principales complicaciones fueron anemia (16.2%), infección urinaria (9.7%), neumonía (9.5%) e infarto del miocardio (0.7%). De quienes fueron incluidos, 57.1% tenían un nivel ASA ≥ 3; se identificó una mortalidad de 16% en ellos. Discusión: El clavo cefalomedular muestra resultados positivos en cuanto a recuperación funcional de la movilidad y una baja prevalencia de complicaciones, con una mortalidad similar a la reportada en la literatura dentro de los primeros 6 meses de nuestro seguimiento.

Abstract: Introduction: Cephalomedullary nails are used for the treatment of hip fractures; however, there are few studies that allow identifying data on the complications of the use of these devices and the results in terms of restoration of the functionality of the patient. Methods: A cross-sectional study of patients with femur fracture was conducted during the period from January 2008 to December 2012. Data on demographic and clinical variables were collected. Telephone follow-up was performed up to six postoperative months. A descriptive analysis was done using absolute and relative frequency measurements. Quantitative variables are presented with averages and standard deviation or median and interquartile range, according to the normality of the data. Results: 82.9% of the patients managed to walk with or without help within six months after surgery; anemia (16.2%), urinary tract infection (9.7%), pneumonia (9.5%) and myocardial infarction (0.7%) were the main complications. Of the patients included, 57.1% had an ASA level ≥ 3; a mortality rate of 16% was identified. Discussion: Cephalomedullary nails show positive results regarding recovery of functional mobility and a low prevalence of complications, with similar mortality to that reported in the literature at 6 months of follow up.

Trombectomía mecánica: técnica de primera elección en el tratamiento ictus isquémico agudo: análisis de beneficios y resultados / Mechanical thrombectomy: first choice therapeutical approach in acute ischemic stroke; analysis of benefits and results

Esta revisión tiene como objetivo el uso de la Trombectomía Mecánica como técnica de primera elección en el tratamiento de Ictus Isquémico Agudo. Materiales y Método: La revisión incluye 9 pacientes con diagnóstico de Ictus Isquémico a los que se le realizo Trombectomía Mecánica, se utilizó el dispositivo de recanalización tipo Solitaire asociado a rtPA intraarterial 10 por ciento de la dosis intravenosa, los criterios diagnósticos: edad, período de ventana, imagen de TC al ingreso. Resultados: 8 pacientes (89 por ciento) correspondieron a oclusión de la circulación Anterior, 1 (11 por ciento) a la oclusión de circulación posterior, la efectividad terapéutica se la evalúo según la Escala de Rankin Modificada, 5 (55 por ciento) obtuvieron recuperación completa de sus funciones, 3 (33 por ciento) presentaron secuelas leves, y 1(11 por ciento) no obtuvo mejoría alguna. Discusión: Los resultados de nuestra revisión son alentadores sobre todo al reducir la secuela discapacitante, deja una ventana abierta para posteriores revisiones sobre estetratamiento.

This review aims to use Trombrectomy Mechanics and technique as choice in the treatment of Acute Ischemic Stroke. Materials and Methods: Age, period: The review included 9 patients with a diagnosis of Ischemic Stroke those who underwent Trombrectomy Mechanics, recanalization device type associated with intra-arterial rtPA Solitaire 10 percent of the intravenous dose, the diagnostic criteria was used with CT. Results: 8 patients (89 percent) were occluded circulation Earlier, 1 (11 percent) to occlusion of posterior circulation, the therapeutic succes was evaluated according to the modified Rankin scale, 5 (55 percent) had complete recovery its functions, 3 (33 percent) had mild sequelae, and 1 (11 percent) not obtained any improvement. Discussion: The results of our review are encouraging especially by reducing the disabling sequel, leave a window open for further review on this treatment.

Tratamiento con vitamina E en pacientes con esteatohepatitis no alcohólica / Vitamin E Treatment for Patients with Nonalcoholic Steatohepatitis

La esteatohepatitis no alcohólica se caracteriza histológicamente por el balonamiento de los hepatocitos, la inflamación lobulillar y la esteatosis. Al sospechar este diagnóstico es importante la exclusión de otras causas de lesión hepática principalmente el consumo excesivo de alcohol; sin embargo, la biopsia es el único método disponible hasta el momento para confirmar el diagnóstico. Para el tratamiento de esta enfermedad, la vitamina E debe ser considerada una terapia de primera línea debido a que en diversos ensayos clínicos se ha observado que aunque sin un impacto significativo en la fibrosis, a dosis de 800 UI día mejora la histología en adultos no diabéticos con NASH confirmado por biopsia. A pesar de los beneficios demostrados con el uso de este medicamento se debe tener en cuenta que no reemplaza los cambios en la dieta y el ejercicio, y que por el contrario, representa un complemento a estas medidas.

Nonalcoholic Steatohepatitis (NASH) is characterized histologically by the ballooning of hepatocytes, lobular inflammation and steatosis. If this diagnosis is suspected, it is important to exclude other causes of liver damage, especially excessive consumption of alcohol. Nevertheless, to date, a biopsy is the only method available to confirm the diagnosis. Vitamin E should be considered a first-line therapy for treatment of this disease because several clinical studies have shown that a dose of 800 UI/day improves the histology of non-diabetic adults suffering from NASH even when there is no significant impact on fibrosis. These results were confirmed by biopsies. Despite the proven benefits of the use of this drug, it is important to be aware that its use cannot replace changes in diet and exercise but rather should be seen as a complement to these measures.

Evidence-based medicine as a tool for clinical decision-making in Puerto Rico

Evidence-based medicine (EBM) is defined as "the process of systematically finding, appraising and using contemporaneous research findings as the basis for clinical decisions". Although EBM has been extensively described across the Americas and Europe, no study has looked at the practice of EBM in Puerto Rico. A cross-sectional analysis based on a 23-item questionnaire was employed. We showed that there is a high use (88%) and familiarity (93%) with EBM, and that physicians keep a positive attitude towards EBM (80%) in Puerto Rico. There is an over-representation of academicians (58.9% vs. 34.6%, p = 0.02) and an under-representation of solo office practitioners (10.5% vs. 26.9%, p = 0.03) among EBM users. Additionally, patient workload (48%), time constraints (36%), and limited access to the Internet (28%) were the most frequently cited obstacles to the practice of EBM in Puerto Rico. Taken together, these results help create a cross-sectional profile of EBM practice among Puerto Rican physicians.

Essentials in the diagnosis and management of peripheral arterial disease

Peripheral arterial disease results from the atherosclerotic involvement of arteries of the upper and lower extremities as well as that of the renal and carotid arteries. In view of the importance of its early recognition we have summarized the clinical manifestations, diagnostic procedures and tests, and the current medical and surgical management including percutaneous revascularization. Algorithms that guide in the diagnostic steps and management decisions have been presented.

Management of urinary tract infections, decubitus ulcer and pneumonia in the aging person

Infections in the older person are common and a significant cause of morbidity and mortality. Infections of the urinary tract, skin and soft tissue infections including decubitus ulcers, antibiotics associated diarrhea and lower respiratory tract infections are particularly important in the elderly because of their frequency. While most initial antibiotic therapy is empiric, its important before treatment to try to document the etiology for better use of antibiotics. Infections of the urinary tract are frequently and potentially serious in the elderly, they must be separated from asymptomatic bacteriuria that requires no therapy. Upper and lower urinary tract infections are frequently caused by aerobic gram negative bacilli and or enterococci. Most authors prefer the use of fluoroquinolones to manage such infections. The elderly with decubitus ulcer presents a problem in management, since these are frequent polymicrobic infections in which anaerobes play an important role. The initial therapy usually involves the combination of a fluoroquinolone plus an antianaerobic agent like clindamycin. C. difficile diarrhea as frequent in nursing home residents as well as the older person with prior antibiotics. The treatment should be with metronidazole and avoid the use of vancomycin. Pneumonias in the elderly can be acquired in the community, the nursing home or during a hospitalization. The etiologic agents that predominate change from S. pneumoniae and atypicals in those from the community to an increase in gram negative pneumonia. The initial treatment as started by most authors as well as guidelines include the use of a new fluoroquinolone like gatifloxacin alone or in combination with a beta-lactamic agent like ceftriaxone. For those infections acquired in the hospital therapy with third or fourth generation cephalosporins, carbapenems, beta-lactams with betalactamase inhibitors alone or in combination with an aminoglucoside and or vancomycin if MRSA is suspected is accepted therapy

Reliability of serum magnesium values during diabetic ketoacidosis in children

OBJECTIVE: To determine the prevalence of hypomagnesemia in diabetic children during diabetic ketoacidosis and following restitution of acid-base balance. METHODS: Eight consecutive diabetic children, ranging in age from 8 to 16 years, hospitalized in the pediatric intensive care unit with diabetic ketoacidosis from October 1st. through December 31st, 1995. A control group of 33 metabolically stable diabetic children, and a control group of 30 healthy children. Both control groups were similar in composition regarding age and sex to the study group. None of the patients in the study group and none of the controls had Magnesium supplementation given to them during the study period. MEASUREMENTS: Total serum Magnesium concentrations were measured from peripheral venous blood in all 71 patients. For the study group serum Magnesium was determined in a serial fashion: 1. upon admission in diabetic ketoacidosis 2. 24 hours after admission 3. 72 hours after admission RESULTS: The prevalence of hypomagnesemia was 62.4 in patients with diabetic ketoacidosis, (Group 1), 25 in patients after partial correction of ketoacidosis, (Group 2), and none in patients after resolution of ketoacidosis, (Group 3). The prevalence of hypomagnesemia was 6 for the chronic, metabolically stable diabetic control group, (Group 4), but 0 for the non-diabetic control group, (Group 5). Average serum Magnesium levels were significantly lower (p less than 0.05), in patients admitted in diabetic ketoacidosis compared to those of both the diabetic and the non-diabetic control groups. Also average serum Magnesium levels were significantly lower (p less than 0.05), in patients with corrected diabetic ketoacidosis than those of the healthy control group. But there were no significant differences (p = 0.59263) in average serum Magnesium levels between the diabetic control group and the diabetic patients after resolution of ketoacidosis. CONCLUSIONS: In this study the prevalence of hypomagnesemia was documented to be higher than the average described elsewhere for pediatric, adult, and coronary intensive care units. As hypomagnesemia is an indication of Magnesium depletion, we speculate that the transient hypomagnesemia detected in our study group is an expression of a state of Magnesium depletion that is masked by correction of acidosis and the Magnesium shifts associated with it. Consequently serum Magnesium values ought to be considered most reliable during and not after correction of

El ambiente interno y externo del adolescente puertorriqueño en el uso del alcohol, las drogas y la violencia / Internal and external environment of the Puerto Rican adolescent in the use of alcohol, drugs and violence

PURPOSE: Identify risk factors associated to violent behavior among adolescent students. METHODS: A survey was conducted using a two-staged stratified cluster sampling design. It represents all junior and high school students of Puerto Rico. Students from 117 schools were administered an anonymous questionnaire. RESULTS: Alcohol use was reported by 78.7 of students, and 14 reported illegal drug use. About 25 committed one violent act during the previous year, and 22 committed two acts or more. Drug use, alcohol use, not getting along with their parents, being a male, school failure and drug use by siblings were identified as risk factors for violent behavior. Church attendance was identified as a protective factor. DISCUSSION: Primary physicians can play an important role in violence prevention through early identification of family violence

Profile of a population using a primary health care center in Puerto Rico

PURPOSE: To describe the services delivered by the Family Medicine Physicians at a Community Health Center. METHODS: All information from patient visits during the natural year 1996 were registered using a commercialized computer program. The information was gathered by different means: initial interview, physician's report, records, and personal interviews. RESULTS: A total of 13,203 visits were registered; this represent a total of 4,493 patients. Most of the patients were women, and with a mean age of 38. As expected, most of the patients have Medicaid. The most common conditions seen were hypertension, diabetes, and respiratory diseases. The mean number of visits during the year for almost all conditions was three. Most of the children and adolescents visit the Center due to respiratory conditions, while adults come due to hypertension, diabetes, and musculoskeletal conditions

Concentración de fluor en orina en tres escuelas rurales y análisis de las tres marcas comerciales de sal de cocina del Municipio de la Unión, Antioquia / Fluoride concentration in urine in 3 rural schools and analysis of three commercial salt brands in the municipality of the Union in Colombia

Durante mucho tiempo se ha utilizado la fluorización del agua y de la sal como medidas preventivas masivas. En Colombia desde 1.984 se esta adicionando el flúor a la sal de cocina.Este estudio describe las concentraciones de flúor en la orina de una población rural. Igualmente, hace el análisis de muestras de sal de cocina recogidas en la misma zona.La muestra fue de 64 niños, entre los 6 y 11 años, que se dividieron en dos subgrupos: de 6 a 8 años y de 9 a 11 años. Se recolectaron dos muestras: en la mañana y después del almuerzo. Se estudiaron mediante el método directo para análisis de flúor con electrodo específico. Para las muestras de sal se utilizó el método del electrodo del ión específico.El flúor esta llegando a la comunidad estudiada. En todos los grupos hubo un incremento en la concentración de flúor en el grupo de 6 a 8 años después del almuerzo.La concentración de flúor en la sal vario en todas las marcas...

Adolescent student's compliance with testicular self examination

To determine what adolescents students know or feel about testicular cancer, (TC) and the testicular self examination, (TSE), technique, 127 males students (mean age 16.14 years) were given a 21 item questionnaire. The role of the primary physician and the role of written and visual educational material were assessed for effectiveness in increasing the regular performance of monthly testicular self examination by male students at a Health Education Course at Cervantes Public School at Bayamón, P.R. Out of 127 male student, only 2.4, (n = 3), initially knew about the symptoms of TC. Analysis of the attitude and knowledge questions revealed that respondents were not sure about general concepts in TC and, were not sure that this cancer could be self diagnosed. This study pretends to assess the effects of modeling and guiding practice as components within a comprehensive testicular self examination education program for adolescents male students. Three groups were studied from 10th, 11th, and 12th, grade. The variables investigated were knowledge of testicular cancer, attitudes toward testicular cancer, and frequency of self reported testicular self examination. The participants then received written material plus a physician's lecture on TC and TSE. Upon follow up, 87.5, (n = 113) of the students reported performing monthly TSE, (P < 0.001), a statistically significant increase in performance. Although 20.3 (n = 26) reported having a physical examination by a physician within the previous 3 months, less than 4.7, (n = 6) reported being taught TSE by a physician. Physicians need to educate males about testicular cancer and its early detection

Aspectos historicos de la bioquimica / Historic aspects of biochemistry

Se hace un recuento de los hechos mas notables en la historia de la bioquimica, desde Paracelso, con la latroquimica hasta los descubrimientos trascendentales de la Biologia Molecular en Inglaterra a principios de este siglo. Especificamente se revisa la historia de las enzimas, el metabolismo en general y la aplicacion de los isotopos, teniendo en cuenta primordialmente a sus precursores

Trombolisis en la disfuncion de protesis tricuspidea de Bjork-Shilley. / Thrombolysis in the dysfunction of the Bjork-Shilley tricuspid prosthesis

Se informa la mejoria obtenida en una protesis tricuspidea de Bjork - Shilley obstruida por trombosis en una paciente con cardiopatia reumatica y empeoramiento progresivo de su disfuncion, que mejoro con el uso de estreptocinasa como farmaco trombolitico. Se administraron 100,000 UI durante la primera hora para bloquear los anticuerpos antiestreptocinasa, y posteriormente 57,500 UI cada hora, hasta completar 3.8 millones de UI en total. Para descartar tromboembolias pulmonares se realizaron gammagramas pulmonares antes y despues del uso de la estreptocinasa y, mediante ecocardiogramas seriados en modo M, bidimensional y Doppler pulsado, se valoro la mejoria paulatina de la protesis obstruida. El estudio hemodinamico realizado al finalizar la aplicacion de la estreptocinasa comprobo la disminucion del gradiente transtricuspideo encontrado en forma inicial. Se concluye que el uso del ecocardiograma acompanado de registro de flujos mediante el sistema Doppler como estudios no invasores, permite valorar el grado de disfuncion, la evolucion y la mejoria despues del empleo de substancias tromboliticas, lo que puede ser un metodo alterno al tratamiento quirurgico en los casos de oclusion trombotica de las protesis cardiacas