New cycloalkyl[b]thiophenylnicotinamide-based α-glucosidase inhibitors as promising anti-diabetic agents: Synthesis, in silico study, in vitro and in vivo evaluations.

In the present study, a series of cycloalkyl[b]thiophenylnicotinamide derivatives against α-glucosidase were synthesized, and evaluated for their in vitro and in vivo anti-diabetic potential. Most of the synthetic analogues exhibited superior α-glucosidase inhibitory effects than the standard drug acarbose (IC50 = 258.5 µM), in which compound 11b with cyclohexyl[b]thiophene core demonstrated the highest activity with an IC50 value of 9.9 µM and showed higher selectivity towards α-glucosidase over α-amylase by 7.4-fold. Fluorescence quenching experiment confirmed the direct binding of 11b with α-glucosidase, kinetics study revealed that 11b was a mixed-type inhibitor, and its binding mode was analyzed using molecular docking. Moreover, analogs compounds 6a-9b, 11b, 12b did not show in vitro cytotoxicity against LO2 and HepG2 cells. Finally, compound 11b exhibited in vivo hypoglycemic activity by reducing the blood glucose levels in sucrose-loaded rats.

Assessment of rehabilitation following subarachnoid haemorrhage in China: findings from the Chinese Stroke Center Alliance.

BACKGROUND: Rehabilitation improves functional recovery in subarachnoid hemorrhage (SAH) patients, and assessing patients for rehabilitation is the first step in this process. However, little is known about clinical practice in China regarding the assessment and provision of rehabilitation for patients with SAH. METHODS: To identify patients hospitalized with SAH and to analyze rehabilitation assessment rates, we used data for 11,234 SAH patients admitted to 861 hospitals from the China Stroke Center Alliance from August 2015 to July 2019. We examined factors for rehabilitation assessment and analyzed the relationship between rehabilitation assessment and outcomes in these patients. RESULTS: Among 11,234 patients with SAH, 6,513 (58.0%) were assessed for rehabilitation. Assessed patients had an increased length of stay (mean ± SD days: 17.3 ± 12.5 versus 11.6 ± 10.5, P = 49.4), a higher Glasgow Coma Scale (GCS) score on admission (mean ± SD GCS score: 12.3 ± 3.8 versus 11.8 ± 4.4, P = 12.2), and were more likely to be admitted to the stroke unit (19.6% versus 13.8%, P = 15.6). In multivariable analysis, factors associated with an increased likelihood of a rehabilitation assessment (p < 0.05) included a longer length of stay (odds ratio [OR], 1.04; 95% confidence interval (CI), 1.04 to 1.05) and care such as dysphagia screening (OR, 1.88; 95% CI, 1.73 to 2.04), DVT prophylaxis (OR, 1.56; 95% CI, 1.41 to 1.72) and vessel evaluation (OR, 1.80; 95% CI, 1.63 to 1.98). For the multivariate analysis of outcomes, patients undergoing rehabilitation assessment had a longer length of stay (OR, 1.96; 95% CI, 1.81 to 2.12), a higher modified Rankin Scale (mRS) score at discharge (OR, 1.49; 95% CI, 1.36 to 1.64), and higher rates of discharge to a rehabilitation center (OR, 3.23; 95% CI, 1.81-5.75). CONCLUSION: More than two-fifths of SAH patients were not assessed for rehabilitation. Rates vary considerably among hospital grades, and there is a need to improve adherence to recommended care for SAH patients.

The different catalytic roles of the metal-binding ligands in human 4-hydroxyphenylpyruvate dioxygenase.

4-Hydroxyphenylpyruvate dioxygenase (HPPD) is a non-haem iron(II)-dependent oxygenase that catalyses the conversion of 4-hydroxyphenylpyruvate (HPP) to homogentisate (HG). In the active site, a strictly conserved 2-His-1-Glu facial triad co-ordinates the iron ready for catalysis. Substitution of these residues resulted in about a 10-fold decrease in the metal binding affinity, as measured by isothermal titration calorimetry, and a large reduction in enzyme catalytic efficiencies. The present study revealed the vital role of the ligand Glu(349) in enzyme function. Replacing this residue with alanine resulted in loss of activity. The E349G variant retained 5% activity for the coupled reaction, suggesting that co-ordinating water may be able to support activation of the trans-bound dioxygen upon substrate binding. The reaction catalysed by the H183A variant was fully uncoupled. H183A variant catalytic activity resulted in protein cleavage between Ile(267) and Ala(268) and the production of an N-terminal fragment. The H266A variant was able to produce 4-hydroxyphenylacetate (HPA), demonstrating that decarboxylation had occurred but that there was no subsequent product formation. Structural modelling of the variant enzyme with bound dioxygen revealed the rearrangement of the co-ordination environment and the dynamic behaviour of bound dioxygen in the H266A and H183A variants respectively. These models suggest that the residues regulate the geometry of the reactive oxygen intermediate during the oxidation reaction. The mutagenesis and structural simulation studies demonstrate the critical and unique role of each ligand in the function of HPPD, and which correlates with their respective co-ordination position.

Microbial treatment for prevention and removal of paraffin deposition on the walls of crude pipelines.

Two bacterial strains, paraffin removal strain and biosurfactant-producing strain, named BHJ-1 and QFL-1, were isolated from oil production wells in Daqing oilfield of China. They were subsequently identified as Bacillus cereus QAU68 and Bacillus subtilis XCCX, respectively. As an indicator of the degradation paraffin, the inoculum concentration of BHJ-1 and QFL-1 were added in different proportions, the optimum proportion was 5:2. In this proportion the degradation rate of paraffin could reach 64 %, the prevention rate of paraffin could reach 55 %.

Dysphagia screening and pneumonia after subarachnoid hemorrhage: Findings from the Chinese stroke center alliance.

BACKGROUND AND PURPOSE: Dysphagia is common and is associated with aspiration pneumonia. However, little is known about the prevalence of and factors influencing dysphagia screening (DS) and pneumonia after subarachnoid hemorrhage (SAH). METHODS: We used data on SAH patients admitted to 1476 hospitals from the China Stroke Center Alliance (CSCA) from August 2015 to July 2019 to analyze the rates of DS and pneumonia. We then conducted univariate and multivariable analyses to examine the relationship between DS and pneumonia. RESULTS: Among 4877 SAH patients who were eligible for DS and had complete data on pneumonia status, 3527 (72.3%) underwent DS, and 1006 (20.6%) developed pneumonia. Compared with patients without pneumonia, patients with pneumonia were older (mean: 63.4 vs. 57.8 years of age), had lower Glasgow Coma Scale (GCS) scores at admission (mean: 13.5 vs. 14.3), were more likely to have dysphagia (15.2% vs. 3.3%), and were more likely to have undergone aneurysm isolation (19.1% vs. 10.0%). In multivariable analyses, factors independently associated with a higher risk of pneumonia were dysphagia [odds ratio (OR), 3.77; 95% confidence interval (CI), 2.85-4.98], age (OR, 1.50 per 10-year increase; 95% CI, 1.40-1.60), male sex (OR, 1.23; 95% CI, 1.02-1.49), arrival at the hospital by emergency medical services (OR, 1.36; 95% CI, 1.16-1.58), nimodipine treatment (OR, 1.42; 95% CI, 1.11-1.81), endovascular embolization of aneurysms (OR, 1.23; 95% CI, 1.03-1.47), cerebral ventricular shunt placement (OR, 2.24; 95% CI, 1.41-3.54), and treatment at a higher grade hospital (OR, 1.44; 95% CI, 1.21-1.71). CONCLUSION: More than a quarter of patients with SAH did not have documented DS, while one-fifth developed pneumonia. DS performance was associated with a lower risk of pneumonia. Randomized controlled trials may be needed to determine the effectiveness of DS.

Ligand-activated peroxisome proliferator-activated receptor-gamma protects against ischemic cerebral infarction and neuronal apoptosis by 14-3-3 epsilon upregulation.

BACKGROUND: Thiazolidinediones have been reported to protect against ischemia-reperfusion injury. Their protective actions are considered to be peroxisome proliferator-activated receptor-gamma (PPAR-gamma)-dependent; however, it is unclear how PPAR-gamma activation confers resistance to ischemia-reperfusion injury. METHODS AND RESULTS: We evaluated the effects of rosiglitazone or PPAR-gamma overexpression on cerebral infarction in a rat model and investigated the antiapoptotic actions in the N2-A neuroblastoma cell model. Rosiglitazone or PPAR-gamma overexpression significantly reduced infarct volume. The protective effect was abrogated by PPAR-gamma small interfering RNA. In mice with knock-in of a PPAR-gamma dominant-negative mutant, infarct volume was enhanced. Proteomic analysis revealed that brain 14-3-3epsilon was highly upregulated in rats treated with rosiglitazone. Upregulation of 14-3-3epsilon was abrogated by PPAR-gamma small interfering RNA or antagonist. Promoter analysis and chromatin immunoprecipitation revealed that rosiglitazone induced PPAR-gamma binding to specific regulatory elements on the 14-3-3epsilon promoter and thereby increased 14-3-3epsilon transcription. 14-3-3epsilon Small interfering RNA abrogated the antiapoptotic actions of rosiglitazone or PPAR-gamma overexpression, whereas 14-3-3epsilon recombinant proteins rescued brain tissues and N2-A cells from ischemia-induced damage and apoptosis. Elevated 14-3-3epsilon enhanced binding of phosphorylated Bad and protected mitochondrial membrane potential. CONCLUSIONS: Ligand-activated PPAR-gamma confers resistance to neuronal apoptosis and cerebral infarction by driving 14-3-3epsilon transcription. 14-3-3epsilon Upregulation enhances sequestration of phosphorylated Bad and thereby suppresses apoptosis.

Underexpression of INPPL1 is associated with aggressive clinicopathologic characteristics in papillary thyroid carcinoma.

PURPOSE: To study the relationship between INPPL1 gene and clinicopathologic characteristics of papillary thyroid carcinoma (PTC). PATIENTS AND METHODS: INPPL1 expression in PTCs was tested by quantitative real-time reverse transcription PCR. The Cancer Genome Atlas (TCGA) RNA-seq data and our mRNA data were used to analyze and reveal the relationship between INPPL1 and aggressive clinicopathologic characteristics of PTC. RESULTS: When compared to normal thyroid tissues, INPPL1 was significantly downregulated in PTC tissues, as revealed by our data and TCGA data. INPPL1 underexpression was remarkably related to aggressive clinicopathologic characteristics such as lymph node metastasis (LNM), histological type, tumor size, mulitifocality, and disease stage in TCGA data. Meanwhile, LNM was confirmed to be associated with underexpression of INPPL1 in our data. In addition, logistic analysis clearly showed that underexpression of INPPL1 was an independent factor for LNM in PTC. CONCLUSION: INPPL1 may be a novel tumor suppressor gene in PTC, which was significantly correlated with aggressive clinicopathologic characteristics, especially LNM.

Biosynthesis of ethyl (S)-4-chloro-3-hydroxybutanoate by NADH-dependent reductase from E. coli CCZU-Y10 discovered by genome data mining using mannitol as cosubstrate.

The reductase (PgCR) from recombinant Escherichia coli CCZU-Y10 displayed high reductase activity and excellent stereoselectivity for the reduction of ethyl 4-chloro-3-oxobutanoate (COBE) into ethyl (S)-4-chloro-3-hydroxybutanoate ((S)-CHBE). To efficiently synthesize (S)-CHBE (>99 % enantiomeric excess (ee)), the highly stereoselective bioreduction of COBE into (S)-CHBE with the whole cells of E. coli CCZU-Y10 was successfully demonstrated in a dibutyl phthalate-water biphasic system. The appropriate ratio of the organic phase to water phase was 1:1 (v/v). The optimum reaction temperature, reaction pH, cosubstrate, NAD(+), and cell dosage of the biotransformation of 100 mM COBE in this biphasic system were 30 °C, 7.0, mannitol (2.5 mmol/mmol COBE), 0.1 µmol/(mmol COBE), and 0.1 g (wet weight)/mL, respectively. Moreover, COBE at a high concentration of (1,000 mM) could be asymmetrically reduced to (S)-CHBE in a high yield (99.0 %) and high enantiometric excess value (>99 % ee). Significantly, E. coli CCZU-Y10 shows high potential in the industrial production of (S)-CHBE (>99 % ee).