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A cyst with mural nodule(s) (CMN) is a rare imaging finding of cerebellar metastasis (CMET). It is a great challenge to differentiate it from cerebellar hemangioblastoma (CHB). In the present study, we explore the differences in the magnetic resonance imaging (MRI) characteristics of the 2 tumors. Patients with pathologically confirmed CMET or CHB at our hospital from July 2009 to September 2021 were enrolled in the present study. All the patients underwent conventional head MRI (before and after contrast administration) before surgery and had ≥1 lesion in the cerebellum that presented as CMN on MRI. The clinical and MRI features were compared between the 2 groups. A total of 33 patients (10 with CMET and 23 with CHB) met the study criteria. The CMET patients were significantly older than were the CHB patients (median age, 59.5 years vs. 37 years; P = 0.002). Compared with the CHB group, the CMET group showed significantly higher occurrence rates of multiple mural nodules (72.7% vs. 8.7%), lack of vascular flow voids (100% vs. 65.2%), isointense or hypointense mural nodules on fluid-attenuated inversion recovery imaging (100.0% vs. 22.7%), restricted diffusion of mural nodules (22.2% vs. 0.0%), mildly enhanced mural nodules (90.9% vs. 4.3%), and a ring-enhanced pattern of the cyst wall (100% vs. 8.7%; P < 0.05 for all). When CMN is detected in the cerebellum on MRI, older age, multiple mural nodules, absence of vascular flow voids, isointense or hypointense mural nodule on fluid-attenuated inversion recovery sequence, restricted diffusion of the mural nodule, mildly enhanced mural nodules, and a ring-enhanced pattern of the cyst wall are the clinical and imaging features that strongly indicate the likelihood of metastasis, rather than CHB. [ABSTRACT FROM AUTHOR]

The asymmetric addition reactions between varied nonaromatic aldehydes and diethylzinc catalyzed by chiral phosphoramide L 1 and thiophosphorodiamide L 4 were thoroughly investigated. Both ligands worked very well for α-branched aliphatic and α-branched α,β-unsaturated aldehydes. For α-nonbranched aliphatic aldehydes, L 4 behaved much better than L 1 . For α-nonbranched α,β-unsaturated aldehydes, L 4 showed high enantioselectivities and L 1 only gave racemic alcohol products. [ABSTRACT FROM AUTHOR]

[Display omitted] In this study, an alcohol dehydrogenase derived from Lactobacillus kefir (LkADH) was engineered and a simple and practical bioreduction system was developed for the preparation of (R)-2-chloro-1-(2, 4-dichlorophenyl) ethanol ((R)-CDPO), a key intermediate for the synthesis of antifungal drugs. Through active pocket iterative saturation mutagenesis, mutant LkADH-D18 (Y190C/V196L/M206H/D150H) was obtained with high stereoselectivity (99% ee, R vs 87% ee , S) and increased activity (0.44 µmol·min−1·mg−1). LkADH-D18 demonstrated NAD(P)H regeneration capability using a high concentration of isopropanol (IPA) as a co-substrate. Using 40% IPA (v/v), 400 mM of (R)-CDPO (90.1 g·L-1) was obtained via complete substrate conversion using 40 mg·mL−1 LkADH-D18 wet cells. The biocatalytic process catalyzed at constant pH with the cheap co-solvent IPA contributed to improved isolated yield of (R)-CDPO (97%), lower reaction cost, and simpler downstream purification, indicating the potential utility of LkADH-D18 in future industrial applications. [ABSTRACT FROM AUTHOR]

The white-rot fungi Phanerochaete chrysosporium have been widely applied in heavy metal bioremediation, which commonly results in a stress exposure. Exposure studies showed that Cd bioaccumulation triggered H 2 O 2 generation. Thereafter, the H 2 O 2 , as signal molecules, activated the enzymatic antioxidant response in the case of the conjunction of SOD and CAT. High levels of R (SOD/CAT) were found initially under Cd exposure, and then a significant decline occurred in time-course Cd exposure. Antioxidant activities also provided an alternative as an indication of the existence of antioxidant response upon Cd exposure, via coupling H 2 O 2 level with the variation in antioxidant activities. This finding potentially has implications for the understanding of tolerance behavior and detoxification mechanisms, which is beneficial to expand the application of P. chrysosporium in bioremediation biotechnology. [ABSTRACT FROM AUTHOR]

Highlights: [•] Low concentration of Pb2+ could enhance the production of OH. [•] OH production declined when the initial Pb2+ concentration reached 400mgkg−1. [•] A remarkable correlation was found between OH content and oxalate concentration. [•] No obvious relationship was found between OH content and lignin degradation rate. [ABSTRACT FROM AUTHOR]

Abstract: We have developed a series of new chiral thiophosphorodiamide ligands derived from (1R,2R)-(+)-1,2-diphenylethylenediamine, which are the structural relatives of thioureas. An investigation into their catalytic properties in asymmetric additions of diethylzinc to aldehydes has shown that N,N,N′,N′-tetra-substituted chiral thiophosphorodiamides can give (R)-secondary alcohols with up to 98% yield and 98% ee, while N,N′-di-substituted chiral thiophosphorodiamides give (S)-secondary alcohols with up to 99% yield and 97% ee values. The enantioselectivity switch is highly efficient with a broad substrate scope. We have also proposed hypothetical reaction pathways, which result in an enantioselectivity switch. [Copyright &y& Elsevier]