Acid-base potentiometric titration using a stainless steel electrode without oxidative treatment.

An AISI 304 stainless steel laminar electrode without oxidative treatment was investigated for the potentiometric titration of hydrochloric acid with sodium hydroxide. The proposed electrode was obtained from metalworking cuttings. Scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray fluorescence spectroscopy and X-ray diffraction were used to study the surface morphology and chemical composition of the electrode. The electrode showed a sensitivity of 59.18 ± 0.37 mV/pH, which was reproducible under intermediate conditions. Potentiometric titration showed a curve with deviations from pH 9.5 with respect to the glass electrode. However, this did not affect the quantification as the jumps of the curves coincided. The endpoint was 9.25 mL for both electrodes and the hydrochloric acid concentration was 0.0845 mol/L, with a deviation of 0.0004 mol/L from the standard concentration of 0.0841 mol/L. The nonartificially oxidised electrode did not show any crystalline oxide phases, whereas after oxidation it showed semicrystalline phases of iron and chromium oxides and increased the crystallinity of the steel. Despite the low content of surface oxides, stainless steel electrodes can give a Nernstian response to pH, depending on the surface characteristics of the material. This leads to the need to calibrate any electrode prior to oxidative treatment to rule out a Nernstian response without surface modification.

An RSV Live-Attenuated Vaccine Candidate Lacking G Protein Mucin Domains Is Attenuated, Immunogenic, and Effective in Preventing RSV in BALB/c Mice.

BACKGROUND: Respiratory syncytial virus (RSV) is a leading viral respiratory pathogen in infants. The objective of this study was to generate RSV live-attenuated vaccine (LAV) candidates by removing the G-protein mucin domains to attenuate viral replication while retaining immunogenicity through deshielding of surface epitopes. METHODS: Two LAV candidates were generated from recombinant RSV A2-line19F by deletion of the G-protein mucin domains (A2-line19F-G155) or deletion of the G-protein mucin and transmembrane domains (A2-line19F-G155S). Vaccine attenuation was measured in BALB/c mouse lungs by fluorescent focus unit (FFU) assays and real-time polymerase chain reaction (RT-PCR). Immunogenicity was determined by measuring serum binding and neutralizing antibodies in mice following prime/boost on days 28 and 59. Efficacy was determined by measuring RSV lung viral loads on day 4 postchallenge. RESULTS: Both LAVs were undetectable in mouse lungs by FFU assay and elicited similar neutralizing antibody titers compared to A2-line19F on days 28 and 59. Following RSV challenge, vaccinated mice showed no detectable RSV in the lungs by FFU assay and a significant reduction in RSV RNA in the lungs by RT-PCR of 560-fold for A2-line19F-G155 and 604-fold for A2-line19F-G155S compared to RSV-challenged, unvaccinated mice. CONCLUSIONS: Removal of the G-protein mucin domains produced RSV LAV candidates that were highly attenuated with retained immunogenicity.

Fungal Necrotizing Scleritis After Intravitreal Injection Therapy.

PURPOSE: To report a case of infectious necrotizing scleritis secondary to Aspergillus terreus after intravitreal injection therapy. METHODS: This is a case report with literature review. RESULTS: A 98-year-old woman receiving intravitreal aflibercept injections for neovascular age-related macular degeneration in the left eye presented with severe pain, redness, and purulent discharge at the injection site. She was initially treated with topical fortified antibiotics, and clinical improvement was achieved, although microbial cultures showed negative results. Two months later, she presented with severe ocular pain and was diagnosed with anterior necrotizing scleritis. Scleral scrapings were collected for cultures, and intensive topical antibiotic therapy was reintroduced. Evaluation for autoimmune etiology and microbiological testing showed negative results. Because of the progression of the scleral necrotic area, empirical therapy with topical voriconazole was initiated, and surgical debridement was performed. Finally, the culture was positive for A. terreus. The modified therapy consisted of topical voriconazole and oral voriconazole for 3 months with an excellent clinical outcome. CONCLUSIONS: To our knowledge, this is the first case of fungal necrotizing scleritis secondary to intravitreal injection. Diagnosis was delayed due to its chronic clinical course and the slow fungal growth in culture media, but the combined medical and surgical approach resulted in a satisfactory outcome.

Technology transfer for the implementation of a clinical trials network on drug abuse and mental health treatment in Mexico / Transferencia de tecnología para la implantación de una red de investigaciones clínicas sobre el tratamiento de la drogadicción y los problemas de salud mental en México

Low- and middle-income countries (LMIC) lack the research infrastructure and capacity to conduct rigorous substance abuse and mental health effectiveness clinical trials to guide clinical practice. A partnership between the Florida Node Alliance of the United States National Drug Abuse Treatment Clinical Trials Network and the National Institute of Psychiatry in Mexico was established in 2011 to improve substance abuse practice in Mexico. The purpose of this partnership was to develop a Mexican national clinical trials network of substance abuse researchers and providers capable of implementing effectiveness randomized clinical trials in community-based settings. A technology transfer model was implemented and ran from 2011-2013. The Florida Node Alliance shared the "know how" for the development of the research infrastructure to implement randomized clinical trials in community programs through core and specific training modules, role-specific coaching, pairings, modeling, monitoring, and feedback. The technology transfer process was bi-directional in nature in that it was informed by feedback on feasibility and cultural appropriateness for the context in which practices were implemented. The Institute, in turn, led the effort to create the national network of researchers and practitioners in Mexico and the implementation of the first trial. A collaborative model of technology transfer was useful in creating a Mexican researcher-provider network that is capable of changing national practice in substance abuse research and treatment. Key considerations for transnational technology transfer are presented.

Los países de ingresos bajos o medios (PIBM) carecen de una infraestructura de investigación y de la capacidad para llevar a cabo investigaciones clínicas rigurosas sobre la eficacia del tratamiento de la drogadicción y los problemas de salud mental que orienten la práctica clínica. Se estableció una asociación entre la Florida Node Alliance de la National Drug Abuse Treatment Clinical Trials Network de los Estados Unidos y el Instituto Nacional de Psiquiatría de México con objeto de mejorar la práctica en materia de tratamiento de la drogadicción en México. La finalidad de esta asociación fue la de crear una red nacional mexicana de investigaciones clínicas constituida por investigadores y proveedores de tratamiento de la drogadicción capaces de ejecutar ensayos clínicos aleatorizados de eficacia en entornos comunitarios. Se implantó un modelo de transferencia de tecnologías. La Florida Node Alliance compartió el el conocimiento y la experiencia para la creación de la infraestructura de investigación con objeto de ejecutar investigaciones clínicas aleatorizadas en programas comunitarios, por medio de módulos de capacitación común y específica, entrenamiento en funciones específicas, emparejamientos, modelado, vigilancia y retroalimentación. El proceso de transferencia de tecnología fue de tipo bidireccional en cuanto se basó en la retroalimentación sobre la viabilidad y la adecuación cultural para el contexto en el que se llevaron a cabo las prácticas. El Instituto, a su vez, lideró la iniciativa para crear la red nacional de investigadores y profesionales de México y llevar a cabo el primer ensayo. Un modelo colaborativo de transferencia de tecnología resultó útil para la creación de una red mexicana de investigadores y proveedores de tratamiento capaz de cambiar las prácticas nacionales de investigación y tratamiento en materia de drogadicción. Se exponen las consideraciones clave para la transferencia transnacional de tecnología.

Tratamiento del cáncer de laringe experiencia en el Instituto Oncológico Doctor Luis Razetti / Laryngeal cancer treatment experience in the Oncology Institute Doctor Luis Razetti

El cáncer de laringe representa un 20%-25% de los carcinomas de cabeza y cuello. Actualmente su tratamiento incluye diversas modalidades, desde cirugía para enfermedad localizada hasta esquemas concurrentes de quimioterapia y radioterapia para estadios avanzados. Evaluar los resultados del tratamiento del carcinoma laríngeo en nuestra institución en el período 2000-2009; por lo que se realizó un estudio retrospectivo analítico basado en las historias clínicas de pacientes con diagnóstico histopatológico de carcinoma laríngeo, en estadios precoces y avanzados no metastásicos. El objetivo primario del estudio es evaluar la supervivencia global, según el estadiaje y/o las modalidades terapéuticas. Los objetivos secundarios incluyen supervivencia libre de enfermedad y supervivencia libre de laringectomía. Un total de 187 pacientes, la sobrevida global fue significativamente mayor en estadios precoces comparado a estadios avanzados (P=0,023). La sobrevida global en estadios avanzados no presentó diferencias estadísticamente significativas independientemente de la modalidad de tratamiento aplicado. La sobrevida libre de laringectomía y libre de enfermedad muestra una tendencia preliminar a favor del tratamiento concurrente definitivo en estadios avanzados. La sobrevida global y libre de enfermedad en estadios precoces no presentó variación de acuerdo a la modalidad del tratamiento definitivo (P=0,086). La radioterapia ofrece una eficacia comparable a la cirugía en estadios precoces, el tratamiento multimodal de estadios avanzados permite una mayor sobrevida libre de laringectomía y libre de enfermedad sin impacto aparente en la sobrevida global en relación con la cirugía radical.

The laryngeal cancer accounts for 20%- 25% of all the head and neck carcinomas. The current treatment includes various forms ranging from surgery for localized disease to concurrent schemes chemotherapy and radiotherapy for the advanced stages. The purpose of this study is to evaluate the results of the treatment of laryngeal carcinoma at our institution in the period 2000-2009. For what was done a retrospective study based on medical records of patients with histopathological diagnosis of laryngeal carcinoma, stage early and in advanced non-metastatic. The primary objective is to evaluate overall survival, according to the staging and or therapeutic modalities we used. The secondary end points included disease free survival, laringectomy free survival. For a total of 187 patients, the overall survival was significantly higher in early stages compared to advanced stages (P=0.023). The global survival in advanced stages did not differ statistically significant regardless of the type of treatment we applied. The free laringectomy survival and the disease free survival show atrend in favor of the preliminary final concurrent treatment in the advanced stages. The overall survival and disease free survival in early stages did not present variation according to the definitive treatment modality (P= 0.086). Radiotherapy offers comparable efficacy to surgery in early stages, multimodal treatment for advanced stages allows greater laringectomy free survival and disease free survival without apparent impact on overall free survival in relation to the radical surgery.

Extracción de cuerpos extraños intrauterinos / Removal of intrauterine foreing bodies

Evaluar la extracción transcervical de cuerpos extraños de la cavidad endometrial por histeroscopia. Estudio descriptivo y retrospectivo sobre hallazgos inusuales y extracción de cuerpos extraños intrauterinos por histeroscopia entre junio 2000 y junio 2005. Unidad de Endoscopia, Hospital Universitario de Caracas. Se identificaron seis casos con cuerpo extraño en cavidad endometrial, entre ellos: fragmento de madera, dispositivo intrauterino (DIU) fragmentado, algodón, catéter de peridural, metaplasia ósea. La histeroscopia es una herramienta indispensable para la evaluación de la cavidad endometrial, y en especial en los casos en los que se sospecha la presencia de un cuerpo extraño intracavitario. La histeroscopia permite el diagnóstico y tratamiento del problema de una forma rápida y segura.

To evaluate the transcervical removal of foreign bodies from the endometrial cavity for hysteroscopy. Descriptive and retrospective study about unusual findings and extraction of intrauterine foreign bodies for hysteroscopy between June 2000 and June 2005. Endoscope Unit of Gynecology Service, University Hospital of Caracas. Six cases with foreign bodies in endometrial cavity were identified, such as wood sticks, intra uterine device fragmentÆs (IUD), piece of cotton, peridural catheter, bone metaplasy. The hysteroscopy is an indispensable tool for the evaluation of the endometrial cavity, and specially in cases with suspicion of intracavitary foreign bodies. The hysteroscopy permit the diagnostic and treatment of the problem with security and safety.

Clinical, functional, and epidemiological differences between atopic and nonatopic asthmatic children from a tertiary care hospital in a developing country.

BACKGROUND: Differences between children with atopic asthma (AA) and nonatopic asthma (non-AA) have been shown in epidemiologic studies. In developing countries, even when non-AA is more prevalent than AA among schoolchildren, no data are available regarding clinical, functional, and epidemiological differences between these 2 groups. OBJECTIVE: To evaluate differences between Chilean children with AA and non-AA. METHODS: In this cross-sectional study, skin prick tests were performed on all patients (age range, 4-14 years) admitted to our tertiary care hospital with the diagnosis of asthma who were consequently classified as having AA or non-AA. Demographic characteristics, spirometry results, exercise bronchial challenge test results, and eosinophil counts measured in the last 12 months were recorded. RESULTS: Among the 237 asthmatic children, 62.5% had AA. Non-AA children had a significantly earlier onset of asthma and a more frequent history of pneumonia and tobacco consumption at home. Children with AA had higher nasal eosinophilia levels and a higher prevalence of dermatitis and severe exacerbation episodes of asthma in the past year (emergency department consultation and oral corticosteroids courses). Lung function was similar in both groups. After the multivariate analysis, only the number of oral steroid courses was significantly different between the groups and was associated with AA. CONCLUSIONS: In this selected population of asthmatic schoolchildren, the prevalence of non-AA (37.6%) is not negligible, and some differences between AA and non-AA children exist.

Claritromicina en amigdalofaringitis aguda estreptocóccica / Clarithromycin in acute streptococcal tonsillopharyngitis

El presente estudio tuvo como objetivo estudiar la eficacia y seguridad de la claritromicina en pacientes de 10 o más años de edad con diagnóstico de amigdalofaringitis aguda estreptocóccica. De 188 pacientes estudiados, 43 (22.8%) tuvieron la prueba rápida (Test Pack Strep A) y el cultivo positivo para Streptococcus pyogenes; 40 fueron tratados con claritromicina a una dosis de 250 mgs/12 horas/10 días. Todas las cepas de S. pyogenes identificadas resultaron ser sensibles In vitro a este nuevo macrólido. En la evaluación clínica, 5-7 días post-tratamiento, 39 (97%) estaban clínicamente curados y el restante presentó mejoría. La evaluación bacteriológica demostró erradicación de la bacteria en 37 (92.5%) y persistencia o recaída en los 3 restantes. Se presentaron pocos efectos adversos y ninguno de ellos obligó a suspender el tratamiento. La claritromicina resultó ser efectiva y bien tolerada en el tratamiento de la amigdalofaringitis aguda estreptocóccica.