In this study we used the deep eutectic solvents (ionic liquids) to investigate the reaction between copper (II) with ethylene diamine (en). Two of the existing methods for analyzing spectrophotometric measurements ha...In this study we used the deep eutectic solvents (ionic liquids) to investigate the reaction between copper (II) with ethylene diamine (en). Two of the existing methods for analyzing spectrophotometric measurements have been applied for establishing, the stoichiometry and whenever possible, the stability constants of the chelates formed. The method of continuous variations was necessary to determine first whether, the metal ion and the ligand ethylene diamine form one or more than one chelate, when more than one chelate formed, the results obtained depend on the wavelength and for meaningful conclusions the wavelengths were carefully selected. The empirical formulae of the chelates were further substantiated by the molar ratio method. The effect of time and temperature on the formation and stability of these chelates in solution is also studied. The stability constants, K1 and K2 for the copper (II) chelates were calculated, though reliable, and are comparable to literature values.展开更多
Photoenzymatic catalysis has become an emerging field in organic synthetic chemistry that provides eco-friendly alternatives to traditional methods. This comprehensive review examines the developing field of photoenzy...Photoenzymatic catalysis has become an emerging field in organic synthetic chemistry that provides eco-friendly alternatives to traditional methods. This comprehensive review examines the developing field of photoenzymatic catalysis, categorized by reaction types and focusing on its application in organic synthesis. This article highlights recent advances in the use of photoenzymatic reactions in carbon-carbon cross-coupling, ketone and alkene reduction, hydroamination, and hydrosulfonylation, mostly by flavin-dependent “ene”-reductases and nitroreductases. In each case, we exemplified the substrate scope that produces products with high yield and enantioselectivity. Additionally, the emerging trends in developing new enzymatic variants and novel reaction pathways that broaden the scope and enhance yield of these reactions were discussed.展开更多
Objective: This case report aimed to demonstrate a possible neuromuscular effect of Latarjet nerves transection or truncal vagotomy, in association with sleeve gastrectomy plus antrojejunostomy, in order to reproduce ...Objective: This case report aimed to demonstrate a possible neuromuscular effect of Latarjet nerves transection or truncal vagotomy, in association with sleeve gastrectomy plus antrojejunostomy, in order to reproduce a Roux-en-Y gastric bypass (RYGB) mechanistic principles, in patients with previous Sleeve Gastrectomy (SG) who had had weight regain, with or without concomitant gastroesophageal reflux disease (GERD). Background: Sleeve gastrectomy (SG) is one of the most frequently performed bariatric operations worldwide. Nevertheless, weight regain and gastroesophageal reflux disease (GERD) have been consistently demonstrated, in association with this technique, which may require a revisional procedure. RYGB is an option in such a situation but, implies in gastrointestinal exclusions, which represents a shortcoming of this revision. Surpassing this inconvenient would be of great value for the patients. Methods: We describe herein two cases of SG revision for weight regain and GERD, with a follow-up of one year. Gastroesophageal reflux disease was evaluated by validated questionnaire, upper endoscopy, seriography, high resolution manometry (HRM) and impedance pHmetry (I-pHmetry), in the pre and postoperative periods. A re-Sleeve Gastrectomy with antrojejunal anastomosis was done in both cases, after informed consents. The Latarjet nerves were transected in one case, due to a bleeding in the left gastric vessels and a truncal vagotomy was required in the other, to appropriately treat an associated hiatal hernia. Results: In the postoperative evaluation it was observed a pyloric spasm in both cases, during seriography and endoscopy, kept until the one-year follow-up. There was unidirectional contrast flow to the gastrointestinal anastomosis, filling the jejunal limb, in radiologic contrast study. No contrast passed through the pylorus. Nonetheless, the duodenum was kept endoscopically accessible. In the one-year evaluation, weight loss was adequate and GERD resolution was obtained in both cases, confirmed by endoscopic and functional esophageal assessment, together with symptoms questionnaire. Conclusion: The association of Latarjet nerves sectioning or truncal vagotomy with re-sleeve gastrectomy plus gastrointestinal anastomosis (antrojejunal), in a revision for a failed sleeve, can represent a technical approach, to reproduce RYGB results, without exclusions and with duodenum endoscopic accessibility maintenance. It maybe could be applied for primary surgeries. Additional studies are necessary to confirm this hypothesis.展开更多
文摘In this study we used the deep eutectic solvents (ionic liquids) to investigate the reaction between copper (II) with ethylene diamine (en). Two of the existing methods for analyzing spectrophotometric measurements have been applied for establishing, the stoichiometry and whenever possible, the stability constants of the chelates formed. The method of continuous variations was necessary to determine first whether, the metal ion and the ligand ethylene diamine form one or more than one chelate, when more than one chelate formed, the results obtained depend on the wavelength and for meaningful conclusions the wavelengths were carefully selected. The empirical formulae of the chelates were further substantiated by the molar ratio method. The effect of time and temperature on the formation and stability of these chelates in solution is also studied. The stability constants, K1 and K2 for the copper (II) chelates were calculated, though reliable, and are comparable to literature values.
文摘Photoenzymatic catalysis has become an emerging field in organic synthetic chemistry that provides eco-friendly alternatives to traditional methods. This comprehensive review examines the developing field of photoenzymatic catalysis, categorized by reaction types and focusing on its application in organic synthesis. This article highlights recent advances in the use of photoenzymatic reactions in carbon-carbon cross-coupling, ketone and alkene reduction, hydroamination, and hydrosulfonylation, mostly by flavin-dependent “ene”-reductases and nitroreductases. In each case, we exemplified the substrate scope that produces products with high yield and enantioselectivity. Additionally, the emerging trends in developing new enzymatic variants and novel reaction pathways that broaden the scope and enhance yield of these reactions were discussed.
文摘Objective: This case report aimed to demonstrate a possible neuromuscular effect of Latarjet nerves transection or truncal vagotomy, in association with sleeve gastrectomy plus antrojejunostomy, in order to reproduce a Roux-en-Y gastric bypass (RYGB) mechanistic principles, in patients with previous Sleeve Gastrectomy (SG) who had had weight regain, with or without concomitant gastroesophageal reflux disease (GERD). Background: Sleeve gastrectomy (SG) is one of the most frequently performed bariatric operations worldwide. Nevertheless, weight regain and gastroesophageal reflux disease (GERD) have been consistently demonstrated, in association with this technique, which may require a revisional procedure. RYGB is an option in such a situation but, implies in gastrointestinal exclusions, which represents a shortcoming of this revision. Surpassing this inconvenient would be of great value for the patients. Methods: We describe herein two cases of SG revision for weight regain and GERD, with a follow-up of one year. Gastroesophageal reflux disease was evaluated by validated questionnaire, upper endoscopy, seriography, high resolution manometry (HRM) and impedance pHmetry (I-pHmetry), in the pre and postoperative periods. A re-Sleeve Gastrectomy with antrojejunal anastomosis was done in both cases, after informed consents. The Latarjet nerves were transected in one case, due to a bleeding in the left gastric vessels and a truncal vagotomy was required in the other, to appropriately treat an associated hiatal hernia. Results: In the postoperative evaluation it was observed a pyloric spasm in both cases, during seriography and endoscopy, kept until the one-year follow-up. There was unidirectional contrast flow to the gastrointestinal anastomosis, filling the jejunal limb, in radiologic contrast study. No contrast passed through the pylorus. Nonetheless, the duodenum was kept endoscopically accessible. In the one-year evaluation, weight loss was adequate and GERD resolution was obtained in both cases, confirmed by endoscopic and functional esophageal assessment, together with symptoms questionnaire. Conclusion: The association of Latarjet nerves sectioning or truncal vagotomy with re-sleeve gastrectomy plus gastrointestinal anastomosis (antrojejunal), in a revision for a failed sleeve, can represent a technical approach, to reproduce RYGB results, without exclusions and with duodenum endoscopic accessibility maintenance. It maybe could be applied for primary surgeries. Additional studies are necessary to confirm this hypothesis.
