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Arabidopsis thaliana hydroxynitrile lyase (AtHNL) engineering has uncovered variants that showed up to 12-fold improved catalytic efficiency than the wild-type towards asymmetric Henry reaction. The AtHNL variants have displayed excellent enantioselectivity, up to >99%, and higher conversion in the synthesis of 13 different (R)-β-nitroalcohols from their corresponding aldehydes. Using cell lysates of Y14M/F179W, we demonstrated a preparative scale synthesis of (R)-1-(4-methoxyphenyl)-2-nitroethanol, a tembamide chiral intermediate, in >99% ee and 52% yield. [ABSTRACT FROM AUTHOR]

Objective: The purpose was to study the ocular manifestations pattern and complications of vernal keratoconjunctivitis (VKC) and efficacy of corticosteroid, cyclosporine, alcaftadine. Material and methods: A Prospective study was done taking 227 patients from 15th Oct 2021 to 15th Mar 2022 in Department of Ophthalmology SLN Medical College and Hospital. Vernal Keratoconjunctivitis (VKC) was diagnosed basing on clinical presentation and scoring of signs and symptoms. Various investigations like slit-lamp biomicroscopy, keratometry, retinoscopy, distant direct, direct ophthalmoscopy and Corneal topography, fundus examination with +90D +20DVolk lenses done. Patients were allocated in 3 groups randomly for studying the efficacy of topical corticosteroid, cyclosporine and alcaftadine as monotherapy and first line therapy too. The results were analyzed after 4, 8 & 12 weeks. Visual acuity and ocular complications were recorded. Results: Most common age group involved was 5 years to 9 year and least were more than of 20 years. Among the patients, 171 (75.4%) were male and 56 (24.6%) were female between 1-30 years. Most common presentation was limbal form. Complications like shield ulcer found in 11 and keratoconus in 2 patients. There was significant reduction in sign and symptom score in topical corticosteroid and topical cyclosporine group. Conclusion: Severe VKC is potentially blinding visual loss may occur due to keratoconus and corneal scars. Topical cyclosporine 0.05% and topical alcaftadine 0.25% which can help to reduce corticosteroid usage, is an effective and safe alternative for the treatment of VKC. [ABSTRACT FROM AUTHOR]

Objectives To evaluate clinico-demographic profile of hypertensive retinopathy cases in a tertiary care hospital of South Odisha, India. Materials and methods: This was a Crosssectional study conducted in the department of Ophthalmology, SLN Medical College, Koraput (Odisha) from July 2021 to February 2022. A total of 226 hypertensive patients were examined out of which 100 were found to manifest hypertensive retinopathy changes. These 100 patients were further evaluated and analyzed. Sample size of the study was 100 number of hypertensive retinopathy patients. Different investigations done in the patients are Visual acuity, refraction, BP measurement, Tonometry, Fundus examination, Gonioscopy, B scan, Renal profile, Blood sugar estimation. Demographic parameters like sources of cases, age, gender, area wise distribution. The cases were again assessed to find out level of hypertension control, duration since hypertensive etc. Results: Hypertensive retinopathy grading distribution among hypertensives with controlled blood pressure was 56.25%, 31.25% and 12.50% into Grade I, II and III respectively, showing lesser incidence of end organ damage with better control of blood pressure levels. Conclusion: There is a significant correlation between increasing age, blood pressure levels and severity of sclerotic changes with severity of retinopathy. Further studies in hypertensive retinopathy patients will definitely decrease the progression of this disease and lower incidences of blindness in our community. [ABSTRACT FROM AUTHOR]

Site-saturation mutagenesis is used for generating replacements for Trp116 of Saccharomyces pastorianus old yellow enzyme (OYE). The analysis of an OYE family member whose native sequence contains Ile at position 116 has shown that this enzyme's stereoselectivity has matched that of the wild-type Saccharomyces pastorianus OYE, indicating that the identity of the residue at position 116 has not solely determined the substrate binding orientation.

Hydroxynitrile lyase (HNL)-catalysed stereoselective synthesis of β-nitro alcohols from aldehydes and nitroalkanes is considered an efficient biocatalytic approach. However, only one S-selective HNL-Hevea brasiliensis (HbHNL)-exists that is appropriate for the synthesis of (S)-β-nitro alcohols from the corresponding aldehydes. Further, synthesis catalysed by HbHNL is limited by low specific activity and moderate yields. We have prepared a number of (S)-β-nitro alcohols, by kinetic resolution with the aid of an R-selective HNL from Arabidopsis thaliana (AtHNL). Optimization of the reaction conditions for AtHNL-catalysed stereoselective C-C bond cleavage of racemic 2-nitro-1-phenylethanol (NPE) produced (S)-NPE (together with benzaldehyde and nitromethane, largely from the R enantiomer) in up to 99 % ee and with 47 % conversion. This is the fastest HNL-catalysed route known so far for the synthesis of a series of (S)-β-nitro alcohols. This approach widens the application of AtHNL for the synthesis not only of (R)- but also of (S)-β-nitro alcohols from the appropriate substrates. Without the need for the discovery of a new enzyme, but rather by use of a retro-Henry approach, it was used to generate a number of (S)-β-nitro alcohols by taking advantage of the substrate selectivity of AtHNL., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)