Hydrothermal synthesis of a photocatalyst based on Byrsonima crassifolia and TiO2 for degradation of crystal violet by UV and visible radiation.

This work presents a one-step synthesis methodology for preparing a hydrochar (HC) doped with TiO2 (HC-TiO2) for its application on the degradation of crystal violet (CV) using UV and visible radiation. Byrsonima crassifolia stones were used as precursors along with TiO2 particles. The HC-TiO2 sample was synthesized at 210 °C for 9 h using autogenous pressure. The photocatalyst was characterized to evaluate the TiO2 dispersion, specific surface area, graphitization degree, and band-gap value. Finally, the degradation of CV was investigated by varying the operating conditions of the system, the reuse of the catalyst, and the degradation mechanism. The physicochemical characterization of the HC-TiO2 composite showed good dispersion of TiO2 in the carbonaceous particle. The presence of TiO2 on the hydrochar surface yields a bandgap value of 1.17 eV, enhancing photocatalyst activation with visible radiation. The degradation results evidenced a synergistic effect with both types of radiation due to the hybridized π electrons in the sp2-hybridized structures in the HC surface. The degradation percentages were on average 20% higher using UV radiation than visible radiation under the following conditions: [CV] = 20 mg/L, 1 g/L of photocatalyst load, and pH = 7.0. The reusability experiments demonstrated the feasibility of reusing the HC-TiO2 material up to 5 times with a similar photodegradation percentage. Finally, the results indicated that the HC-TiO2 composite could be considered an efficient material for the photocatalytic treatment of water contaminated with CV.

Use of a bioabsorbable mesh in midline laparotomy closure to prevent incisional hernia: randomized controlled trial.

INTRODUCTION: The objective was to assess the effectiveness and safety of a bioabsorbable mesh at the time of closure of a midline laparotomy for IH prevention. MATERIALS AND METHODS: A multicenter, randomized clinical trial including patients undergoing abdominal surgical procedures through a midline laparotomy incision was designed. In the group of mesh (n = 167) the incision was closed using a continuous polydioxanone suture (PDS) plus a bioabsorbable mesh. In the control group (n = 165) a continuous PDS single layer suture was only used. Patients were randomly assigned (1:1) to the two groups. The primary outcome was the incidence of IH at 6, 12 and 24 months. Assessment of IH was done using a CT scan. RESULTS: At 6 months, the rates of IH were 15.2% and 24.8% in the experimental and control groups, respectively (relative risk [RR] 0.66, 95% confidence interval [CI] 0.38-0.98, P = 0.042). At 12 months, the rate of IH continued to be significantly lower in the experimental group (21.4% vs. 33.1%, P = 0.033), but at 24 months, there were no significant differences between the study groups with a follow-up rate of only 37.5%. The number needed to treat (NNT) was 11 and 9 at 6 and 12 months, respectively. CONCLUSION: The bioabsorbable mesh significantly prevented IH during the first year. Not reliable conclusions can be drawn across the second year. This may suggest that the any of the closing technique assessed in this study would have a "palliative" transient effect for preventing IH in the long-term.

Evaluación por gastroscopia simple y cromoendoscopia convencional de la superficie gastroesofágica y duodenal proximal del equino. Estudio piloto / Evaluation by simple gastroscopy and conventional chromoendoscopy of the gastro-esophageal and proximal duodenal surface of equine. Preliminary study

RESUMEN Las enfermedades gastrointestinales equinas tienen una alta incidencia con un pronóstico variable en la práctica clínica. La mayoría de los estudios se limitan a describir lesiones ulcerativas y lesiones inflamatorias. El objetivo de este estudio fue evaluar el potencial diagnóstico complementario de la cromoendoscopia convencional en la mucosa gas-troesofágica y duodenal proximal del equino. El estudio incluyó 20 caballos criollos colombianos de ambos sexos (12 hembras y 8 machos), con edades entre 5 y 20 años, peso entre 250 y 350 kilogramos, condición corporal 4-5/9 y con historial de alteraciones digestivas en los últimos 3 meses; quienes previo a la evaluación por gastroscopia y cromoendoscopia se sometieron a ayuno (sólidos 12h y líquidos 4h) y sedación (xilacina 0,5 mg/kg/iv). Se utilizaron tinciones como rojo fenol, lugol, índigo carmín, azul de metileno y ácido acético y se tomaron biopsias de los segmentos que mostraron reacción. El azul de metileno reveló 52% de las lesiones, el lugol 19%; por su parte, el rojo fenol, el índigo carmín y el ácido acético revelaron el 9,5% restante. El epitelio escamoso fue el más afectado (66,6%), el glandular (19%), antro pilórico (9,5%) y duodeno proximal (4,7%). Los hallazgos histopatológicos fueron hiperplasia, hipertrofia, hiperqueratosis, congestión, degeneración vacuolar, infiltrados celulares, fibrosis, necrosis y atrofia en diferentes grados de severidad. La cromoendoscopia reveló lesiones prematuras, que pasaron desapercibidas con las técnicas convencionales de endoscopia del tracto digestivo. Este es el primer estudio que emplea la cromoendoscopia en equinos; a pesar de que la técnica mejoró la visualización y facilitó la ubicación y descripción de lesiones ulcerativas prematuras a través de la histopatología, se recomiendan mayores estudios controlados y con un número más amplio de muestras.

ABSTRACT Equine gastrointestinal diseases have a high occurrence with a variable prognostic in clinic practice. Most of the studies limits to describe ulcerative and inflammatory lesions. The objective of this study was to evaluate the potential complementary diagnostic of conventional chromoendoscopy on the gastroesophageal and proximal duodenal mucosa of the equine. 20 Colombian creole horses, of both sexes (12 females and 8 males), with ages between 5 and 20 years old, weight between 250 and 350 kilograms, body condition 4-5/9, that had presented digestive alterations in the last 3 months, were subjected to fasting (solids 12h and liquids 4h) and sedated (xylazine 0,5 mg/kg/iv) to be evaluated by gastroscopy and chromoendoscopy, using for stains phenol red, lugol, indigo carmine, methylene blue and acetic acid, taking biopsy samples of the segments that showed reaction. The methylene blue revealed 52%, lugol 19%, and phenol red, indigo carmine and acetic acid revealed only 9,5% of the lesions, being the squamous epithelium the most affected (66,6%), glandular epithelium (19%), pyloric antrum (9,5%) and proximal duodenum (4,7%), where histopathological findings were hyperplasia, hypertrophy, hyperkeratosis, congestion, vacuolar degeneration, cellular infiltrates, fibrosis, necrosis and atrophy in different degrees of severity. Chromoendoscopy revealed lesions premature, which go unnoticed with conventional light endoscopy techniques. This is the first study using chromoscopy in horses to show that the reagents used allow a better visualization of injuries than the conventional technique, helping histopathological studies and molecular biology to understand ulcerative premature injuries and possible pathophysiological pathways. However, larger controlled studies and a larger number of samples are needed.

Jejunal diverticula causing massive intestinal bleeding.

Small bowel diverticula are rare formations and some are prone to complications such as lower gastrointestinal bleeding. We report the case of a patient with hemorrhagic shock following upper gastrointestinal bleeding. A 39-year-old patient was admitted to the unit for recurrent bleeding. The patient received transfusions and selective arteriography was performed which reported bleeding at the level of the ileocolic artery. Laparatomy was performed and blood was found at the entire colon and small intestine up to 40 cm of Treitz angle where multiple diverticula were visualized. Bowel resection was performed. Although duodeno-jejunal diverticula are rare, a special attention should be paid to this clinical entity as it can be a cause of recurrent upper gastrointestinal bleeding.