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This study reports sequential dehydrogenation and transfer oxygenation of 1,2-diarylepoxides by high-valent phenCu(III)(CF3)3 and DMSO to produce 1,2-diketones. The Cu(III)-CF3 compound serves as a CF3 radical source to abstract the hydrogen atom of the epoxide ring. The resulting ether α-carbon radical undergoes ring-opening rearrangement to give a ketone α-carbon radical intermediate, which is oxygenated by DMSO with the release of Me2S. The combination of a Cu(III)-CF3 compound and DMSO may be exploited to develop other novel oxidation reactions.
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In order to improve the degradation activity of ß-glucosidase (CpBgl) from Coniophora puteana, the structural modification was conducted. The enzyme activity of mutants CpBgl-Q20C and CpBgl-A240S was increased by 65.75% and 58.58%, respectively. These mutants exhibited maximum activity under the same conditions as wild-type CpBgl (65 â and pH 5.0), slightly improved stabilities compared that of the wild-type, and remarkably enhanced activities in the presence of Mn2+ or Fe2+. The Vmax of CpBgl-Q20C and CpBgl-A240S was increased to 138.18 and 125.14 µmol/mg/min, respectively, from 81.34 µmol/mg/min of the wild-type, and the catalysis efficiency (kcat/Km) of CpBgl-Q20C (335.79 min-1/mM) and CpBgl-A240S (281.51 min-1/mM) was significantly improved compared with that of the wild-type (149.12 min-1/mM). When the mutant CpBgl-Q20C were used in the practical degradation of different biomasses, the glucose yields of filter paper, corncob residue, and fungi mycelia residue were increased by 17.68%, 25.10%, and 20.37%, respectively. The spatial locations of the mutation residues in the architecture of CpBgl and their unique roles in the enzyme-substrate binding and catalytic efficiency were probed in this work. These results laid a foundation for evolution of other glycoside hydrolases and the industrial bio-degradation of cellulosic biomass in nature.
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Celulose , beta-Glucosidase , Biomassa , beta-Glucosidase/metabolismo , Mutação , Celulose/metabolismoRESUMO
AIM: To evaluate the therapeutic effect of pupilloplasty combined with phacomulsification and intraocular lens implantation (PPI) in uveitis-induced cataract. METHODS: Total 28 patients with uveitis-induced cataract were enrolled. Within 3mo before the PPI, 7 cases accompanied with glaucoma maintained carteolol hydrochloride for lowering intraocular pressure, and 1 case maintained glucocorticoid for anti-inflammation. The baseline characteristics, treatment processes, and outcomes of enrolled cases were retrospectively analyzed. Hematoxylin and eosin (HE) staining was performed to reveal the histopathological changes of iris tissues. RESULTS: Iris hemorrhage was the only intraoperative complication observed in 2 cases. After the surgery, normal intraocular pressure, right position of intraocular lens, and improved visual gain [best corrected visual acuity (BCVA)>0.5] were achieved. Postoperative keratic precipitates was observed in 2 cases, which was recovered within 1wk. During the follow-up of 5-10y, no recurrence of uveitis was found in 27 cases (96.43%). Uveitis only recurred in one case with the onset of ankylosing spondylitis. HE staining showed iris stroma (all samples), pigment cell hyperplasia in pigment epithelium (n=9) and stroma (n=19), inflammatory cell infiltration in iris (n=7), and neovascularization in iris surface (n=2). CONCLUSION: PPI improves the visual gain and prevents the long-term recurrence of uveitis in patients with uveitis-induced cataract, including those with preoperative intraocular pressure abnormality (glaucoma) and inflammation (active uveitis). Uveitis presents stroma atrophy, pigment cell hyperplasia, and inflammatory cell infiltration, even in a quiet state.
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OBJECTIVE: We aimed to develop a predictive nomogram for the early detection of hydrocephalus in children with bacterial meningitis. METHODS: This retrospective study was based on data of children with bacterial meningitis admitted to our hospital between January 2016 and December 2020. Risk factors were evaluated using univariate analysis, and the predictive model/nomogram was built using binary logistic analysis. A nomogram calibration plot, Hosmer-Lemeshow test and receiver operating characteristic (ROC) curve evaluated the predictive performance. Ordinary bootstrapping processed the internal validation. RESULTS: We enrolled 283 patients who matched the inclusion criteria, among whom 41 cases (14.49%) had confirmed bacterial meningitis-associated hydrocephalus (BMAH). The incidence of sequelae in the patients with BMAH was 88.9% (24/27), which was significantly higher than that in the patients without BMAH. Univariate regression analysis revealed that 14 clinical indicators were associated with BMAH. Multivariate analysis identified 4 variables as independent risk factors to establish the predictive model: repeated seizures, loss of consciousness, procalcitonin ≥7.5 ng/dL and mechanical ventilation. And a graphical nomogram was designed. The area under the ROC curve was 0.910. In the Hosmer-Lemeshow test the P value was 0.610. The mean absolute error in the calibration plot was 0.02. Internal validation showed the testing set was in good accordance with the original set when internal validation was performed. CONCLUSIONS: The predictive model/nomogram of BMAH could be used by clinicians to determine hydrocephalus risk.
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Hidrocefalia , Meningites Bacterianas , Criança , Humanos , Hidrocefalia/complicações , Meningites Bacterianas/complicações , Meningites Bacterianas/diagnóstico , Meningites Bacterianas/epidemiologia , Nomogramas , Prognóstico , Estudos RetrospectivosRESUMO
BACKGROUND: We aimed to study seizure characteristics during the acute phase of Japanese encephalitis (JE) in children, determine the risk factors of postencephalitic epilepsy (PEE), establish a risk prediction model for the disease, and construct a nomogram to visualize the model. METHODS: We retrospectively analyzed the clinical data and follow-up results of 328 children with JE who were hospitalized between January 2011 and December 2020. Risk factors were screened using univariable analysis, a predictive model was built using binary logistic analysis, lasso regression was used for variable screening, and a nomogram was developed. RESULTS: Of the 328 children with JE enrolled in the study, 216 (65.9%, 216/328) had seizures in the acute phase. The incidence of PEE was 14.7% (39/264), The cumulative percentages of PEE after discharge was 10.6% (28/264)at 6 months, which increased to 13.6%(36/264)at 3 years. 38.5% of patients with PEE had generalized onset seizures, and 17.9% had focal motor seizures. Univariable analysis revealed that 22 clinical indicators were related to the PPE; Multivariable analysis identified seizure number >5 (OR (95%CI) = 3.013 (1.046-8.676), P = 0.041), status epilepticus (OR (95%CI) = 3.918 (1.212-12.669), P = 0.023), and Coma (OR (95%CI) = 22.495 (8.686-58.285), P<0.001) as independent risk factors for PEE. The risk prediction model: ln(p/1p)= -3.533 + 1.103 × (seizures number > 5) +1.366 × (status epilepticus) + 3.113 × (Coma) was developed, and a nomogram was constructed. The area under the ROC curve (AUC), calibration plot, and Hosmer-Lemeshow test showed that the model had good discrimination and calibration. Ordinary bootstrapping was used for internal validation, and the predictive results of the original and test sets were consistent. CONCLUSIONS: Seizure is a common manifestation during acute encephalitis and sequelae in children with JE. The nomogram constructed in this study could be used for early prediction, and could facilitate early intervention.
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Encefalite Japonesa , Epilepsia , Estado Epiléptico , Criança , Coma , Encefalite Japonesa/complicações , Encefalite Japonesa/epidemiologia , Epilepsia/diagnóstico , Epilepsia/epidemiologia , Epilepsia/etiologia , Humanos , Estudos Retrospectivos , Fatores de Risco , Convulsões/complicações , Estado Epiléptico/etiologiaRESUMO
BACKGROUND: One prominent pathological feature of congenital aniridia is hypoplasia of the iris, often accompanied by other eye abnormalities. The objective of this study is to identify gene mutations responsible for autosomal dominance in a Chinese family with congenital aniridia, progressive cataracts and mental retardation. METHODS: A total of 11 family members, including 6 affected and 5 unaffected individuals were recruited. Whole exome sequencing was performed on the proband and Sanger sequencing was applied to identify the causal mutation in the other family members and control samples. RESULTS: A heterozygous mutation, c. 112delC (p. Arg38fs) in PAX 6, was identified in the family that was associated with congenital aniridia, progressive cataracts and mental retardation. The mutation was exclusively observed in all affected individuals but not in unaffected family members or unrelated healthy controls without aniridia recruited from Beijing Tongren Hospital. Bioinformatics analysis indicated that the mutation c. 112delC (p. Arg38fs) in PAX 6 affected sugar phosphate backbone construction, leading to half reduction of the full-length protein. Other symptoms such as lens opacity, keratitis, lens dislocation, ciliary body hypoplasia, foveal hypoplasia and mental development retardation were also observed in this family. CONCLUSION: These results provided a new insight into the effects of PAX 6 as a mutational hotspot, with a symptom complex that includes congenital aniridia, progressive cataracts and mental retardation. These findings suggested the cognitive treatment of PAX 6-mutated individuals could be considered earlier clinically, combined with medication or surgery of congenital aniridia and progressive cataracts.
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Aniridia/genética , Povo Asiático/genética , Catarata/genética , Mutação da Fase de Leitura , Deficiência Intelectual/genética , Fator de Transcrição PAX6/genética , Adulto , Criança , Pré-Escolar , China/epidemiologia , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Linhagem , Polimorfismo de Nucleotídeo Único , Recidiva , Tomografia de Coerência Óptica , Sequenciamento do ExomaRESUMO
BACKGROUND/PURPOSE: A three-generation Chinese family with autosomal dominant congenital nuclear cataract was recruited. This study aimed to identify the disease-causing gene for nuclear cataract with functional dissections of the identified mutant. METHODS: Detailed clinical data and family history were recorded. Candidate gene sequencing was performed to identify the disease-causing mutation. Recombinant connexin50 (Cx50) wild type and mutant constructs were synthesized. Triton X-100 solubility and subcellular localization of the recombinant Cx50 proteins were analyzed in HeLa cells. Apoptosis was assayed as the percentage of fragmented nuclei in transfected cells. RESULTS: All affected individuals in the family displayed clear phenotypes of dense nuclear cataracts. A c.227 G > A variation was found in the coding region of Cx50, which arginine residue at position 76 was substituted by histidine (p.R76H). This mutation was co-segregated with the disease in the family, and was not observed in 110 unrelated Chinese controls. No statistically significant differences were found in the Triton X-100 solubility and apoptosis rate between wild type and mutant Cx50 in HeLa cells. However, Cx50 mutant was unable to form gap junctional plaques between adjacent cells as the wild type proteins did. CONCLUSION: This study identified a novel cataract phenotype caused by the p.R76H mutation in Cx50, providing evidence of further phenotypic heterogeneity associated with this mutation. Functional analysis showed that the mutation affected the formation of gap junction channels and led to opacity in the lens.
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Catarata/congênito , Catarata/genética , Conexinas/genética , Proteínas do Olho/genética , Sequência de Aminoácidos , Povo Asiático/genética , Estudos de Casos e Controles , China , Feminino , Células HeLa , Humanos , Masculino , Mutação , Mutação de Sentido Incorreto , Linhagem , Fenótipo , Proteínas Recombinantes/genética , TransfecçãoRESUMO
Long noncoding RNAs (lncRNA) have been recognized as significant regulators in the progression of atherosclerosis (AS). Oxidized low-density lipoprotein (ox-LDL) can induce macrophage inflammation and oxidative stress, that serves important roles in AS. However, the exact function of lncRNA NEAT1 and its possible molecular mechanism in AS remain unclear. Here, we concentrated on the roles and molecular mechanisms of NEAT1 in AS development. In our current study, we observed that NEAT1 was elevated by ox-LDL in a dose-dependent and time-dependent manner. RAW264.7 cell survival was greatly enhanced, and cell apoptosis was significantly inhibited by LV-shNEAT1 transfection. In addition, knockdown of NEAT1 in RAW264.7 cells repressed CD36 expression and foam cell formation while NEAT1 overexpression shown an opposite process. Moreover, NEAT1 downregulation inhibited inflammation molecules including IL-6, IL-1ß, and TNF-α. Meanwhile, silencing of NEAT1 can also suppress reactive oxygen species (ROS) and malondialdehyde (MDA) levels with an enhancement of superoxide dismutase (SOD) activity in RAW264.7 cells. MicroRNAs are some short RNAs, and they can regulate multiple biological functions in many diseases including AS. Here, we found that miR-128 expression was remarkably decreased in ox-LDL-incubated RAW264.7 cells. Interestingly, miR-128 mimics was able to reverse AS-correlated events induced by overexpression of NEAT1. By using bioinformatics analysis, miR-128 was predicted as a target of NEAT1 and the correlation between them was validated in our study. Taken these together, it was implied that NEAT1 participated in ox-LDL-induced inflammation and oxidative stress in AS development through sponging miR-128.
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PURPOSE: To identify the CRYBA1/A3 mutation spectrum and analyze the genotype-phenotype correlations in Chinese families with congenital cataract. METHODS: Family history and clinical data of 47 unrelated families with autosomal dominant congenital cataract (ADCC) were recorded. CRYBA1/A3 gene sequencing was applied to identify the causative mutation. Haplotypes were constructed using closely linked microsatellite markers and intragenic single-nucleotide polymorphisms (SNPs) to compare the affected haplotype in three families. RESULTS: Nuclear cataract was the most common type of ADCC in Chinese families, accounting for 42.6% (20/47). A recurrent CRYBA1/A3 deletion mutation (ΔG91) was identified in three families (6.4%) with nonprogressive nuclear congenital cataract. Different haplotypes segregated with the mutation in each family. CONCLUSIONS: A recurrent ΔG91CRYBA1/A3 mutation occurs independently in 6.4% of the Chinese families with autosomal dominant nuclear cataracts and most likely represents a mutational hot spot, which underscores the relations between nonprogressive nuclear cataract and CRYBA1/A3.