Chiral amines in enantiopure forms are important chemical building blocks, which are most well recognized in the pharmaceutical industries for imparting desirable biological activity to chemical entities. A number of synthetic strategies to produce chiral amines via biocatalytic as well as chemical transformation have been developed. Recently, ω-transaminase (ω-TA) has attracted growing attention as a promising catalyst which provides an environment-friendly access to production of chiral amines with exquisite stereoselectivity and excellent catalytic turnover. To obtain enantiopure amines using ω-TAs, either kinetic resolution of racemic amines or asymmetric amination of achiral ketones is employed. The latter is usually preferred because of twofold higher yield and no requirement of conversion of a ketone product back to racemic amine. However, the choice of a production process depends on several factors such as reaction equilibrium, substrate reactivity, enzyme inhibition, and commercial availability of substrates. This review summarizes the biochemical features of ω-TA, including reaction chemistry, substrate specificity, and active site structure, and then introduces recent advances in expanding the scope of ω-TA reaction by protein engineering and public database searching. We also address crucial factors to be considered for the development of efficient ω-TA processes.

Technical skills in mastoidectomy surgery can be acquired during even brief practice on the VR temporal bone simulator. It is anticipated that longer periods of practice presented within the fundamentals of comprehensive curriculum will facilitate procedural learning. Further studies are required to elucidate evidence of transference of these skills to the operating room and to procedures of greater complexity.

Secondary aortoenteric fistula (SAEF) is a rare yet lethal cause of gastrointestinal bleeding and occurs as a complication of an abdominal aortic aneurysm repair. Clinical presentation may vary from herald bleeding to overt sepsis and requires high index of suspicion and clinical judgment to establish diagnosis. Initial diagnostic tests may include computerized tomography scan and esophagogastroduodenoscopy. Each test has variable sensitivity and specificity. Maintaining the hemodynamic status, control of bleeding, removal of the infected graft, and infection control may improve clinical outcomes. This review entails the updated literature on diagnosis and management of SAEF. A literature search was conducted for articles published in English, on PubMed and Scopus using the following search terms: secondary, aortoenteric, aorto-enteric, aortoduodenal, aorto-duodenal, aortoesophageal, and aorto-esophageal. A combination of MeSH terms and Boolean operators were used to device search strategy. In addition, a bibliography of clinically relevant articles was searched to find additional articles (Appendix A). The aim of this review is to provide a comprehensive update on the diagnosis, management, and prognosis of SAEF.

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The dynamic and crucial role of tubulin in different cellular functions rendered it a promising target in anticancer drug development. Combretastatin A-4 (CA-4), an inhibitor of tubulin polymerization isolated from natural sources, is a lead molecule with significant cytotoxicity against tumour cells. Owing to its non polar nature it exhibits low solubility in natural biological fluids, thereby prompting the development of new CA-4 based derivatives. The modification of this lead molecule was mostly carried out by keeping the crucial -orientation of the double bond intact, along with a trimethoxyphenyl aromatic ring, by employing different approaches. The issue of solubility was also addressed by the development of water soluble prodrugs of CA-4. The present review highlights the investigations into the parallel development of both new CA-4 based derivatives and prodrugs in the past few years.