Efectividad del protocolo ACTG076 en la transmisión vertical en embarazadas con VIH/SIDA. Enero 2011- septiembre 2017

La transmisión vertical del VIH es prevenible, aplicando los protocolos de profilaxis a tiempo. Su objetivo principal es reducir la transmisión vertical del VIH mediante la detección universal del virus en embarazadas y la ejecución de pautas para la disminución de la exposición al virus por parte del recién nacido. Objetivo General: Analizar la efectividad del Protocolo ACTG076 en la transmisión vertical del VIH/SIDA en pacientes atendidas en la consulta de Infectología del Hospital "Dr. Rafael González Plaza" en el período comprendido entre enero 2011 a septiembre 2017. Metodología: Se trata de una investigación de tipo observacional descriptiva, transversal y retrospectiva. La muestra estuvo conformada por 56 embarazadas mayores de 12 años, diagnosticadas con VIH. Resultados: Se estudiaron un total de 52 recién nacidos en quienes se cumplió completamente el Protocolo ACTG076 y los cuales resultaron negativos para VIH (92,86 %). Solo 4 recién nacidos resultaron positivos (7,14 %). Con relación a los recién nacidos que resultaron positivos, habría que mencionar que en 2 casos, sus madres no cumplieron con el protocolo y en los restantes 2 lo recibieron de manera incompleta. Se registró una edad promedio de 30,61 años ± 0,73 años, predominando aquellas embarazadas con edades comprendidas entre los 26 y 33 años (53,57 %). Fueron más frecuentes las embarazadas pertenecientes al estrato IV (44,64 %). También aquellas en segunda gestación (53,57 %) y con embarazos controlados (89,29 %). Un 50 % de las embarazadas estudiadas fue diagnosticado antes del embarazo, seguidas de aquellas diagnosticadas durante el embarazo (44,64 %). El nivel de CD4 estuvo comprendido entre 200 y 500 (46,43 %). En la segunda toma el nivel de CD4 que predominó fue el mayor a 500 (44,64 %). La carga viral predominante fue de menos de 20 copias (53,57 %). Conclusión: Se demostró que mediante el cumplimiento del Protocolo ACTG076 existe una alta efectividad en la prevención de la transmisión vertical del VIH.

Vertical transmission of HIV is preventable, appyling prophylaxis protocols on time. Their main goal is to reduce vertical HIV transmission through universal detection of the virus in pregnant and implementing guidelines to reduce the newborn exposure to the virus. General Objective: To analyze the effectiveness of the ACTG076 Protocol in the vertical transmission of HIV / AIDS in patients treated at the Infectious Diseases Consultation of "Dr. Rafael González Plaza" Hospital in the period from January 2011 to September 2017. Methods: It was a descriptive, observational, transversal and retrospective research. Sample consisted of 56 pregnant women over 12 years, diagnosed with HIV and treated at the health center and the time period described above. Results: A total of 52 newborns received complete ACTG076 protocol, resulting negative for HIV (92.86 %). There were 4 positive newborns (7.14 %). Two of them were born from women which not received ACTG076 protocol or received an incomplete one. An average age of 30.61 ± 0.73 years was recorded. Pregnant women between 26 and 33 years old predominated (53.57 %). Pregnant women who belongs to stratum IV were most frequently found (44.64 %). Also those with a second pregnancy (53.57 %) and controlled pregnancies (89.29 %). A 50.% of pregnant women studied were diagnosed before pregnancy, followed by those diagnosed during pregnancy (44.64). The level of CD4 was between 200 and 500 (46.43 %). It was over 500 and the second test (44.64 %). The viral load that predominated was less than 20 copies (53.57 %). Conclusion: It was demonstrated that there is a high effectiveness in preventing vertical transmission of HIV by fulfilling all stages of the protocol ACTG076.

Molecular dynamics simulations of surface oxide-water interactions on Pt(111) and Pt/PtCo/Pt3Co(111).

Classical molecular dynamics simulations of the interactions of water with oxidized Pt(111) and Pt/PtCo/Pt(3)Co(111) surfaces are performed by modeling water with the CF1 central force model that allows molecular dissociation and therefore the presence of other intermediates of the oxygen reduction reaction different from atomic oxygen. It is found that the water-surface oxide interactions do not affect the overall structure of the catalyst represented by an extended periodic slab. However, such interactions are affected by changes in the electrochemical potential which are simulated by higher values of the surface and atomic oxygen charges at increased oxygen coverage. Thus, electrochemical potential as well as the presence of protons and anions products of acid dissociation define the identity and the amount of oxygen reduction reaction intermediates such as OH or H(3)O. We observe agglomerations of water molecules over regions of the surface and the presence of OH and H(3)O in their vicinity. Our simulation model is able to qualitatively reproduce features of the degradation of the catalyst surface after oxidation and reduction cycles.

Surface segregation and stability of core-shell alloy catalysts for oxygen reduction in acid medium.

Density functional theory is used for the evaluation of surface segregation, trends for dissolution of Pt surface atoms in acid medium, and oxygen reduction reaction activity of core-shell materials, containing a monolayer of platinum over a monometallic or bimetallic core. Two groups of cores are investigated: Pt/X with X = Ir, Au; Pd, Rh, Ag; Co, Ni, Cu; and Pt/Pd(3)X, with X = Co, Fe, Cr, V, Ti, Ir, Re. It is found that all the 4d and 5d pure cores may serve as stable cores, and their beneficial effect on the Pt monolayer may be further tuned by alloying the core to another element, here chosen from 3d or 5d groups. The Pd(3)X cores enhance the stability of the surface Pt atoms both in vacuum and under adsorbed oxygen; however the high oxygen philicity of some of the X elements induces their surface segregation that may cause surface poisoning with oxygenated species and their dissolution in acid medium.

A multifaceted intervention to prevent American cutaneous leishmaniasis in Colombia: results of a group-randomized trial / Prevención de leishmaniasis cutánea americana en Colombia mediante una intervención múltiple: resultados de un ensayo de grupos aleatorios

Introducción. La leishmaniasis cutánea americana es endémica en Colombia, donde cada año son notificados aproximadamente 6000 casos nuevos. En la actualidad las medidas de prevención y control están limitadas al diagnóstico y tratamiento de los casos. Objetivo. Evaluar la eficacia de una intervención múltiple para prevenir la transmisión de Leishmania en el foco endémico de Tumaco, costa Pacífica de Colombia. Materiales y métodos. Se realizó un ensayo de grupos aleatorizados. Veinte veredas fueron pareadas según prevalencia de Leishmania, habitantes y participación comunitaria y luego asignadas aleatoriamente a intervención o control. La intervención incluyó toldillos impregnados con deltametrina, repelente (N, N-dietil-m-toluamida 20 por ciento y Permetrina 0,5 por ciento), modificación de lugares de reposo para los vectores y educación. Al cabo de un año se comparó la incidencia de infección y enfermedad producida por Leishmania en los dos grupos, se monitorearon la adherencia a la intervención y la aparición de efectos adversos. Los resultados finales fueron ajustados por el efecto de correlación intra-grupo. Resultados. Se presentaron 10 casos de leishmaniasis cutánea americana en el grupo que recibió la intervención y 23 en el grupo control, OR=0,42, IC95 por ciento 0,14-1,26. La intervención tuvo un mayor efecto en los niños menores de 10 años, en aquellos que residían en la periferia de la vereda y en veredas con una prevalencia de infección en niños pequeños mayor del 1 por ciento. Se reportaron eventos adversos leves asociados con el uso de los toldillos impregnados y el repelente en 2 por ciento de los participantes. Conclusión. Los casos nuevos de Leishmaniasis cutánea americana se redujeron en un 58 por ciento en el grupo que recibió la intervención. Sin embargo, el número pequeño de casos hace que la estimación de la medida de efecto sea imprecisa y no nos permite afirmar que la intervención tiene un efecto protector. Poblaciones específicas podr...

Introduction. American cutaneous leishmaniasis is endemic in Colombia, where approximately 6.000 new cases are reported every year. Current prevention and control measures are restricted to the diagnosis and treatment of cases. Objective. To evaluate the efficacy of a multifaceted intervention to prevent the transmission of Leishmania in the endemic focus of Tumaco, on the Pacific Coast of Colombia. Materials and methods. A group-randomized trial was conducted. Twenty villages were matched according to prevalence of Leishmania infection, number of inhabitants and level of community participation, and then randomly assigned to intervention or control. The intervention included deltamethrin-impregnated bednets, repellent (20% diethyltoluamide and 0.5% permethrin), modification of sand fly resting sites, and health education. Villages were under surveillance for one year and the use of the intervention measures monitored. The incidence of American cutaneous leishmaniasis and Leishmania infection in the two groups were compared, adherence to the intervention and adverse events were monitored, and the results were adjusted for village intraclass correlation. Results. Ten cases of American cutaneous leishmaniasis were confirmed in the intervention and 23 in the control group, OR = 0.42, 95% CI 0.14-1.26. The intervention had a greater effect in children < 10 years old, in people living on the periphery of the village and in villages with a prevalence of infection in small children > 1%. Adverse events associated with the use of the bednets and the repellent were reported in 2% of the participants and were always mild. Conclusion. Incident cases of American cutaneous leishmaniasis were reduced by 58% in the intervention group. However, the small number of cases renders the effect estimate imprecise and precludes us to claim a protective effect for the intervention. Specific populations could be the targets of simpler and more cost-effective interventions in the future.

Comparative immunohistological analysis of the Montenegro skin test reaction in asymptomatic infection and in acute and chronic cutaneous leishmaniasis / Análisis inmunohistopatológico comparativo de la reacción a la prueba cutánea de Montenegro en infección asintomática y en leishmaniasis cutánea aguda y crónica

Introducción. La reacción a la prueba cutánea de Montenegro (a leishmanina) y la lesión de leishmaniasis comparten características fundamentales de la reacción de hipersensibilidad de tipo retardado. Objetivos. Determinar si la respuesta cutánea a leishmanina se aproxima y podría modelar la respuesta inflamatoria e inmune temprana a la infección por Leishmania. Materiales y métodos. Este estudio comparó la respuesta inflamatoria de biopsias de lesiones agudas (tiempo de evolución £1 mes) y lesiones crónicas (tiempo de evolución ³6 meses) con su respectiva reacción a la prueba cutánea de Montenegro, y con la reacción a la prueba de Montenegro de individuos infectados asintomáticos. Resultados. La proporción de linfocitos T CD4+ y CD8+, células fagocíticas mononucleares y granulocitos fue similar entre lesiones agudas y sus reacciones a la prueba cutánea a leishmanina. En contraste, los linfocitos CD4+ (32,6 por ciento) representaron una proporción significativamente mas baja, y los linfocitos B (20 por ciento) y macrófagos (27 por ciento) una proporción significativamente más alta del infiltrado celular en lesiones crónicas que en sus correspondientes reacciones a la prueba cutánea de Montenegro (CD4+: 43,7 por ciento, linfocitos B: 0.9 por ciento; macrófagos: 17,5 por ciento). Se encontró una asociación positiva entre linfocitos T CD8+ y macrófagos ( P=0,038) en la reacción a la prueba cutánea de Montenegro de los individuos con infección asintomática, mientras que los linfocitos T CD8+ y CD4+ estuvieron asociados positivamente en las reacciones a la prueba cutánea de Montenegro de pacientes crónicos ( P=0,002). Adicionalmente, la proporción de linfocitos B en lesiones crónicas (20 por ciento) fue más alta que en lesiones agudas (5,3 por ciento) ( P=0,002). Conclusión. La reacción cutánea de Montenegro permitió diferenciar la respuesta celular inmune entre infección asintomática y enfermedad crónica, y simula la respuesta temprana a la infección.

Introduction. The Montenegro skin test reaction and leishmaniasis lesions share fundamental characteristics of a delayed type hypersensitivity reaction. Objectives. To determine whether the Montenegro skin test reaction (response to leishmanin) might approximate and thereby provide insight into the early inflammatory and immune response to Leishmania infection. Materials and methods. We compared the inflammatory response in biopsies of acute (evolution time £one month), and chronic lesions (evolution time ³6 months) with the Montenegro skin test reaction in the corresponding patients, and with the Montenegro skin test of asymptomatically infected volunteers. Results. The proportion of CD4+ and CD8+ T lymphocytes, mononuclear phagocytes and granulocytes were similar in acute lesions and in their corresponding Montenegro skin test reactions. In contrast, CD4+ lymphocytes (32.6%) represented a significantly lower, and B cells (20%) and macrophages (27%) a significantly higher proportion of the cellular infiltrate in chronic lesions as compared to reactions in the corresponding skin test site (CD4+: 43.7%, B cells: 0.9%; macrophages: 17.5%). CD8+ T lymphocytes and macrophages were positively associated ( P=0.038) in the Montenegro skin test of asymptomatically infected individuals whereas CD8+ and CD4+ T cells were positively associated in the Montenegro skin test of chronic patients ( P=0.002). Notably, B cells were markedly more frequent in chronic lesions (20%) than in acute lesions (5.3%) ( P=0.002). Conclusion. The Montenegro skin test distinguished the cellular immune response to Leishmania in asymptomatic infection and chronic disease and may provide a surrogate of the early response to infection.

Very late frontal relapse of medulloblastoma mimicking a meningioma in an adult: usefulness of 1H magnetic resonance spectroscopy and diffusion-perfusion magnetic resonance imaging for preoperative diagnosis: case report.

OBJECTIVE AND IMPORTANCE: We present a rare case of very long-term medulloblastoma relapse in an adult patient and discuss the pattern of recurrence and metabolic imaging of the tumor. CLINICAL PRESENTATION: A 45-year-old man was referred for evaluation of a frontobasal midline tumor 21 years after treatment of a cerebellar medulloblastoma by surgery followed by chemotherapy and craniospinal radiotherapy. Magnetic resonance images were suggestive of a meningioma. Several hypotheses were discussed, such as other radio-induced tumors, sarcomas, high-grade gliomas, or lymphomas (previous chemotherapy) and even recurrence of medulloblastoma. Preoperative exploration included H magnetic resonance single-voxel spectroscopy (35 and 135 ms echo time), diffusion imaging, and perfusion magnetic resonance imaging. INTERVENTION: On magnetic resonance spectroscopy, N-acetyl-aspartate and an elevated choline/creatine ratio were retrieved, with a huge unidentified peak at 1.27 parts per million (ppm). Myoinositol signal was present at both echo times. On diffusion imaging, the tumor appeared hyperintense, with a low apparent diffusion coefficient value of 0.689. In the perfusion study, the maximal relative cerebral blood volume was 2. Metabolic imaging favored the diagnosis of medulloblastoma over the initially suspected diagnosis of meningioma. The patient underwent complete removal of the tumor that was confirmed to be a metastasis of his primary medulloblastoma. The postoperative course was uneventful, and complementary courses of radiotherapy and chemotherapy were planned. CONCLUSION: Late relapse should be considered, even after several decades, on occurrence of a second intracranial tumor in this context. Our observation validates the clinical interest of preoperative metabolic imaging for brain tumors with distinctive pattern.

Comparative immunohistological analysis of the Montenegro skin test reaction in asymptomatic infection and in acute and chronic cutaneous leishmaniasis.

INTRODUCTION: The Montenegro skin test reaction and leishmaniasis lesions share fundamental characteristics of a delayed type hypersensitivity reaction. OBJECTIVES: To determine whether the Montenegro skin test reaction (response to leishmanin) might approximate and thereby provide insight into the early inflammatory and immune response to Leishmania infection. MATERIALS AND METHODS: We compared the inflammatory response in biopsies of acute (evolution time < or = one month), and chronic lesions (evolution time > or = 6 months) with the Montenegro skin test reaction in the corresponding patients, and with the Montenegro skin test of asymptomatically infected volunteers. RESULTS: The proportion of CD4+ and CD8+ T lymphocytes, mononuclear phagocytes and granulocytes were similar in acute lesions and in their corresponding Montenegro skin test reactions. In contrast, CD4+ lymphocytes (32.6%) represented a significantly lower, and B cells (20%) and macrophages (27%) a significantly higher proportion of the cellular infiltrate in chronic lesions as compared to reactions in the corresponding skin test site (CD4+: 43.7%, B cells: 0.9%; macrophages: 17.5%). CD8+ T lymphocytes and macrophages were positively associated (P = 0.038) in the Montenegro skin test of asymptomatically infected individuals whereas CD8+ and CD4+ T cells were positively associated in the Montenegro skin test of chronic patients (P = 0.002). Notably, B cells were markedly more frequent in chronic lesions (20%) than in acute lesions (5.3%) (P = 0.002). CONCLUSION: The Montenegro skin test distinguished the cellular immune response to Leishmania in asymptomatic infection and chronic disease and may provide a surrogate of the early response to infection.

A multifaceted intervention to prevent American cutaneous leishmaniasis in Colombia: results of a group-randomized trial.

INTRODUCTION: American cutaneous leishmaniasis is endemic in Colombia, where approximately 6.000 new cases are reported every year. Current prevention and control measures are restricted to the diagnosis and treatment of cases. OBJECTIVE: To evaluate the efficacy of a multifaceted intervention to prevent the transmission of Leishmania in the endemic focus of Tumaco, on the Pacific Coast of Colombia. MATERIALS AND METHODS: A group-randomized trial was conducted. Twenty villages were matched according to prevalence of Leishmania infection, number of inhabitants and level of community participation, and then randomly assigned to intervention or control. The intervention included deltamethrin-impregnated bednets, repellent (20% diethyltoluamide and 0.5% permethrin), modification of sand fly resting sites, and health education. Villages were under surveillance for one year and the use of the intervention measures monitored. The incidence of American cutaneous leishmaniasis and Leishmania infection in the two groups were compared, adherence to the intervention and adverse events were monitored, and the results were adjusted for village intraclass correlation. RESULTS: Ten cases of American cutaneous leishmaniasis were confirmed in the intervention and 23 in the control group, OR = 0.42, 95% CI 0.14-1.26. The intervention had a greater effect in children < 10 years old, in people living on the periphery of the village and in villages with a prevalence of infection in small children > 1%. Adverse events associated with the use of the bednets and the repellent were reported in 2% of the participants and were always mild. CONCLUSION: Incident cases of American cutaneous leishmaniasis were reduced by 58% in the intervention group. However, the small number of cases renders the effect estimate imprecise and precludes us to claim a protective effect for the intervention. Specific populations could be the targets of simpler and more cost-effective interventions in the future.

Photographic and luminometric detection of luciferase reporter phages for drug susceptibility testing of clinical Mycobacterium tuberculosis isolates.

Luciferase reporter phages (LRPs) have proven to be efficient tools for drug susceptibility testing of Mycobacterium tuberculosis. Luminometric detection of LRP activity offers higher sensitivity and quantitative results, while a Polaroid film detection method offers a "low-tech" inexpensive alternative that is called the Bronx box. In this work we evaluated, improved, and compared the performance of the luminometer and the Bronx box formats for drug susceptibility testing with LRPs by using 51 clinical isolates of M. tuberculosis, with the agar proportion method (PM) serving as reference. The sensitivity in detecting resistance to isoniazid and rifampin, antibiotics that define multidrug resistance (MDR), was 100% for both methods. The turnaround time for results was reduced from 3 weeks for PM to 54 or 94 h for luminometry or the Bronx box, respectively. These results support the utility of LRPs as a screening test for the surveillance of MDR tuberculosis.

Aspectos ultraestructurales de las lesiones producidas por mycobacterium spp en el sida / Ultraestructural aspects of the lesions induced by mycobacterium spp in aids

Se estudiaron con el microscopio electrónico muestras de lesiones necrotizantes en ocho casos con infecciones por mycobacterium spp, los cuales forman parte de 230 casos de autopsias en pacientes con SIDA realizadas entre 1984 y 1995 en el Instituto Anatomopatológico de la Universidad Central de Venezuela. Se señalan diversos aspectos sobre la ultraestructura de las micobacterias y sobre las alteraciones que provocan en los tejidos ante el déficit inmunológico que tienen dichos enfermos