Sulfur Poisoning and Self-Recovery of Single-Site Rh1 /Porous Organic Polymer Catalysts for Olefin Hydroformylation.

Sulfur poisoning and regeneration are global challenges for metal catalysts even at the ppm level. The sulfur poisoning of single-metal-site catalysts and their regeneration is worthy of further study. Herein, sulfur poisoning and self-recovery are first presented on an industrialized single-Rh-site catalyst (Rh1 /POPs). A decreased turnover frequency of Rh1 /POPs from 4317 h-1 to 318 h-1 was observed in a 1000 ppm H2 S co-feed for ethylene hydroformylation, but it self-recovered to 4527 h-1 after withdrawal of H2 S, whereas the rhodium nanoparticles demonstrated poor activity and self-recovery ability. H2 S reduced the charge density of the single Rh atom and lowered its Gibbs free energy with the formation of inactive (SH)Rh(CO)(PPh3 -frame)2 , which could be regenerated to active HRh(CO)(PPh3 -frame)2 after withdrawing H2 S. The mechanism and the sulfur-related structure-activity relationship were highlighted. This work provides an understanding of heterogeneous ethylene hydroformylation and sulfur-poisoned regeneration in the science of single-atom catalysts.

Short-chain fatty acids inhibit bovine rumen epithelial cells proliferation via upregulation of cyclin-dependent kinase inhibitors 1A, but not mediated by G protein-coupled receptor 41.

Short-chain fatty acids (SCFAs) play a critical role in regulation of rumen epithelial growth. The mechanisms underlying the regulatory effects of SCFAs on the proliferation of bovine rumen epithelial cells (BRECs) remain unknown; however, SCFAs can bind to G protein-coupled receptor 41 (GPR41); hence, the regulatory effects of SCFAs on BRECs proliferation may be mediated by GPR41. Here, we investigated the molecular mechanisms underlying the effects of SCFAs and GPR41 on BRECs proliferation. We demonstrated that SCFAs activate the expression of GPR41 and inhibit (p < .05) BRECs proliferation, while the GPR41 knockdown (GPR41KD) BRECs exhibited (p < .05) slow proliferation compared with controls. The treatment of BRECs with 10 mM SCFAs significantly enhanced (p < .05) expression of cyclin-dependent kinase inhibitors 1A (CDKN1A), 2A (CDKN2A) and 2B (CDKN2B) and inhibited (p < .05) their transition from G1 to S phase of the cell cycle, compared with controls. Remarkably, the GPR41KD BRECs treated with SCFAs restored high level of CDKN1A, relative to GPR41KD BRECs, but did not affect (p > .05) the expression of CDKN2A and CDKN2B. The GPR41KD BRECs had significantly reduced (p < .05) cyclin-dependent kinase 4 (CDK4) and cyclin D2 mRNA abundance compared with controls. The GPR41KD BRECs treated with SCFAs significantly decreased (p < .05) CDK4, cyclin D2, CDKN2A and CDKN2B mRNA abundance compared with BRECs treated with SCFAs. Overall, our results demonstrated that downregulation of CDK4 and cyclin D2 likely mediates the inhibitory effects of GPR41KD on BRECs proliferation. Additionally, CDKN1A plays a vital role in mediating the inhibitory effect of SCFAs on the BRECs proliferation, and that these changes are not mediated by GPR41.

Prognosis and subtype analysis of left ventricular noncompaction in adults: A retrospective multicenter study.

BACKGROUND: Left ventricular noncompaction (LVNC) is a heterogeneous myocardial disorder with an uncertain prognosis. There was a lack of studies on LVNC subtypes at present. This study sought to identify the prognosis of the overall population of LVNC and to describe the distribution of different subtypes and compare their prognosis. HYPOTHESIS: Patients with different subtypes of LVNC may have different prognoses. METHODS: Patients who fulfilled the Jenni criteria and/or Petersen criteria were included. Major adverse cardiovascular events (MACE) were defined as a combination of heart failure (HF) hospitalization and all-cause mortality. RESULTS: A total of 200 patients from four hospitals were included. The mean age at diagnosis was 48.2 years, and 61.5% of the patients were male. Left ventricular ejection fraction (LVEF) < 50% was present in 54% of the patients. Over a mean retrospective time period of 22.2 months, 47 (23.5%) patients experienced MACE. Age (hazard ratio [HR] 1.03; 95% confidence interval [CI] 1.01-1.06; p = .004), LVEF < 50% (HR 2.32; 95% CI 1.09-4.91; p = .028) and ventricular tachycardia/ventricular fibrillation (HR 2.17; 95% CI 1.08-4.37; p = .03) were significantly associated with the risk of MACE. The most common subtype was dilated LVNC (51.3%), followed by benign LVNC (21.3%) and LVNC with arrhythmias (10.5%). Patients with dilated LVNC had significantly increased cumulative incidence of MACE, HF hospitalization, and all-cause mortality (p < .05). CONCLUSIONS: Age, LVEF < 50%, and ventricular tachycardia/ventricular fibrillation were independent risk factors for prognosis of LVNC. The most common subtype was dilated LVNC, which had a worse prognosis.

The Differential Expression of Circular RNAs in Type 2 Diabetes Mellitus and Latent Autoimmune Diabetes in Adults.

Objective: Expression of circular RNAs (circRNAs) in the peripheral blood of individuals with latent autoimmune diabetes in adults (LADA) and type 2 diabetes mellitus (T2DM) were quantified to identify dysregulated circRNAs compared with control individuals. Methods: circRNAs were obtained from the peripheral blood serum of 12 healthy adults and 12 individuals with LADA and 12 type 2 diabetics. The circRNA expression profiles were analyzed by high-throughput RNA sequencing. The most highly dysregulated circular RNAs were validated by quantitative real-time polymerase chain reaction. A circular RNA-microRNA (miRNA) network diagram predicted the interactions of circular RNAs, miRNAs, and coding genes. Results: A total of 2334 differentially expressed circRNAs were detected among the three groups, with 277 circRNAs in the Group DM versus Group NG; 992 circRNAs in the Group LADA versus Group NG and 1065 circRNAs in the Group DM versus Group LADA. Six circRNAs were identified as the most distinctive differentially expressed targets (p < 0.05). The proposed molecular functions of these differentially expressed circRNAS included the tumor necrosis factor signaling pathway, the FoxO signaling pathway, cellular senescence, and long-term potentiation (all false discovery rate p < 0.05) which may contribute to T2DM and LADA. Conclusion: circRNAs are aberrantly expressed in the peripheral blood of patients with T2DM and LADA and may interact with miRNA and circRNA-derived peptides in the development of diabetes. Further investigations may illustrate the partial pathogenesis of diabetes mellitus. Clinical Trial Registration number: ChiCTR1900020644.

[Comparison of extent of postoperative hydrocephalus in patients between intervertional therapy with embolism and craniotomy occlusion in Hunt-Hess III-IV level aneurysm induced subarachnoid hemorrhage and their prognosis].

OBJECTIVE: To analyze and compare the difference and prognosis between vascular embolization and craniotomy occlusion in patients suffering from aneurysmal subarachnoid hemorrhage (aSAH) with Hunt-Hess level III-IV, and acute postoperative hydrocephalus. METHODS: A retrospective study was conducted on 767 patients who had undergone vascular embolization (vascular embolization group, n = 403) or craniotomy occlusion operation (craniotomy occlusion operation group, n = 364), and the patients with postoperative acute hydrocephalus were screened. The clinical data of patients of both groups was analyzed. By judging short-term prognosis in patients with hydrocephalus with Glasgow outcome scale (GOS) score estimated at discharge, the advantages and disadvantages of two surgical procedures were compared. RESULTS: The number of cases with postoperative hydrocephalus in vascular embolization group was 56 (13.90%), while that in craniotomy occlusion group was 33 (9.07%). The difference between the two groups of incidence of hydrocephalus was statistically significant (χ (2) = 4.350, P = 0.037). In 767 patients with aSAH, the incidence of hydrocephalus among the patients after the hematoma removal operation was significantly lower than that of patients without hematoma removal [3.07% (11/358) vs. 19.07% (78/409), χ (2) = 47.635, P = 0.000]. The incidence of hydrocephalus among the patients after ventricular drainage was significantly lower than that of patients without the drainage [2.77% (19/685) vs. 85.37% (70/82), χ (2) = 487.032, P = 0.000]. In 403 cases of vascular embolization group, the incidence of hydrocephalus in the patients after the hematoma removal operation was lower than that of patients without it [8.06% (5/62) vs. 14.96% (51/341), χ (2) = 2.082, P = 0.168]. The incidence of hydrocephalus in the patients after the ventricular drainage was lower than that of patients without drainage [2.59% (9/347) vs. 83.93% (47/56), χ (2) = 266.599, P = 0.000]. In 364 cases of craniotomy occlusion operation group, the incidence of hydrocephalus in the patients after hematoma removal operation was significantly lower than that of patients did not receive [2.03% (6/296) vs. 39.71% (27/68), χ (2) = 95.226, P = 0.000]. The incidence of hydrocephalus among the patients after the ventricular drainage was significantly lower than that of patients without drainage [2.96% (10/338) vs. 88.46% (23/26), χ (2) = 203.852, P = 0.000]. The difference in incidence of hydrocephalus between the patients who had hematoma removal surgery between vascular embolization group and craniotomy occlusion operation group was statistically significant [8.06% (5/62) vs. 2.03% (6/296), χ (2) = 4.411, P = 0.027], while no statistically difference was present in ventricular drainage patients [2.59% (9/347) vs. 2.96% (10/338), χ (2) = 0.085, P = 0.819]. There were 23 patients (41.07%) with good outcome (GOS score 4-5), while 33 (58.93%) with poor outcome (GOS score 1-3) in 56 patients undergone vascular embolization operation. Good result (GOS score 4-5) was shown in 21 (63.64%) and 12 (36.36%) with poor outcome (GOS score 1-3) among 33 patients with hydrocephalus after craniotomy occlusion operation, and the difference was statistically significant (χ (2) = 4.230, P = 0.039). CONCLUSIONS: Hematoma is one of the main factor contributing to the differences in the incidence of postoperative hydrocephalus of Hunt-Hess grade III-IV patients either receiving vascular embolization or craniotomy occlusion operation. Lateral ventricle drainage may not be the factor that contributes to the difference in incidence of hydrocephalus formation between the vascular embolization and craniotomy occlusion operation groups in Hunt-Hess level III-IV patients. The short term prognosis in the craniotomy occlusion operation group is superior to that of endovascular intervention embolization group.

[Progress in biotransformation of triptolides and bufadienolides].

The latest results from our research group in the biotransformation of triptolides and bufadienolides were reviewed. The trends in the development of biotransformation in the future were also briefly discussed.

Efficient preparation of derivatives of resibufogenin using microbial catalytic technique.

Microbial catalysis is a useful biotechnology in studies on natural products, by which a diversity of novel or active compounds can be obtained. Structural modifications of resibufogenin (1) by hydroxylases, isomerase and glucosyltransferase in Mucor subtilissimus AS 3.2454 were investigated. Eleven products were obtained, and, on the basis of their spectral data, their structures were identified as 12beta-hydroxyresibufogenin (2), 11beta-hydroxyresibufogenin (3), 16alpha-hydroxyresibufogenin (4), 12beta-hydroxy-3-epi-resibufogenin (5), 12alpha-hydroxyresibufogenin (6), 1beta,11beta-dihydroxyresibufogenin (7), 12beta,16alpha-dihydroxyresibufogenin (8), 12alpha,16alpha-dihydroxyresibufogenin (9), 7alpha-hydroxyresibufogenin (10), 1beta,12beta-dihydroxyresibufogenin (11) and resibufogenin 12-O-beta-D-glucoside (12), respectively, of which 3, 5, 7, 11 and 12 are new compounds. This microbial catalytic process was efficient for the production of derivatives of resibufogenin giving 11 products and an overall yield of 93.60%.

Cytotoxic biotransformed products from triptonide by Aspergillus niger.

The diterpenoid triepoxides are the major active constituents of Tripterygium wilfordii with potent antitumor and immune activities. But the strong toxicity of these compounds has restricted their application to a great extent. In order to find more effective compounds with less toxicity, structural modifications of triptonide (1) by Aspergillus niger (AS 3.739) were investigated and four biotransformed products were obtained. Based on their chemical and spectral data, their structures were elucidated as 5alpha-hydroxytriptonide (2), triptolide (3), 17-hydroxytriptonide (4), and 16-hydroxytriptonide (5), among which 2, 4 and 5 are new compounds. All the three new transformed products showed cytotoxic activities against the majority of the human tumor cell lines tested, however, they are found to possess less cytotoxic activity when compared with 1. Both compounds 4 and 5 showed similar cytotoxic activity and their IC (50) values were 5-15 fold less than 1, while 2 is about 100 times less active than 1.

Biotransformation of triptolide and triptonide by cell suspension cultures of Catharanthus roseus.

Catharanthus roseus cell suspension cultures were used to bioconvert both triptolide (1) and triptonide (2). The same reaction path was followed in both biotransformations. Two biotransformed products were obtained and their structures identified as triptriolide (3) and 12beta,13alpha-dihydroxytriptonide (4), respectively, from 1 and 2. Product 4 is a new compound.

Microbial metabolism of artemisinin by Mucor polymorphosporus and Aspergillus niger.

Artemisinin (1) was transformed by Mucor polymorphosporus and Aspergillus niger. Five products were identified as 9beta-hydroxyartemisinin (2), 3beta-hydroxyartemisinin (3), deoxyartemisinin (4), 3beta-hydroxydeoxyartemisinin (5), and 1alpha-hydroxydeoxyartemisinin (6). Products 2, 3, and 6 are new compounds.