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Total syntheses of the biologically important and structurally unique tetracyclic diterpenes conidiogenone, conidiogenol, and conidiogenoneâ B of the cyclopiane class are reported. The absolute configuration of naturally occurring conidiogenoneâ B was also corrected. The key step of our strategy involved the highly efficient construction of both ringâ C and the quaternary carbon center shared by rings A and C through a one-step regioselective and diastereoselective cycloenlargement in the form of a semipinacol-type rearrangement. In particular, the desired regioselectivity was made possible by properly adjusting the migratory aptitude of the migrating carbon atom through the introduction of an electron-donating phenylthio group at this position.
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Diterpenos/síntese química , Cristalografia por Raios X , Diterpenos/química , Estrutura MolecularRESUMO
BACKGROUND: The objectives of this study were to identify hub genes and biological pathways involved in lung adenocarcinoma (LUAD) via bioinformatics analysis, and investigate potential therapeutic targets. AIM: To determine reliable prognostic biomarkers for early diagnosis and treatment of LUAD. METHODS: To identify potential therapeutic targets for LUAD, two microarray datasets derived from the Gene Expression Omnibus (GEO) database were analyzed, GSE3116959 and GSE118370. Differentially expressed genes (DEGs) in LUAD and normal tissues were identified using the GEO2R tool. The Hiplot database was then used to generate a volcanic map of the DEGs. Weighted gene co-expression network analysis was conducted to cluster the genes in GSE116959 and GSE118370 into different modules, and identify immune genes shared between them. A protein-protein interaction network was established using the Search Tool for the Retrieval of Interacting Genes database, then the CytoNCA and CytoHubba components of Cytoscape software were used to visualize the genes. Hub genes with high scores and co-expression were identified, and the Database for Annotation, Visualization and Integrated Discovery was used to perform enrichment analysis of these genes. The diagnostic and prognostic values of the hub genes were calculated using receiver operating characteristic curves and Kaplan-Meier survival analysis, and gene-set enrichment analysis was conducted. The University of Alabama at Birmingham Cancer data analysis portal was used to analyze relationships between the hub genes and normal specimens, as well as their expression during tumor progression. Lastly, validation of protein expression was conducted on the identified hub genes via the Human Protein Atlas database. RESULTS: Three hub genes with high connectivity were identified; cellular retinoic acid binding protein 2 (CRABP2), matrix metallopeptidase 12 (MMP12), and DNA topoisomerase II alpha (TOP2A). High expression of these genes was associated with a poor LUAD prognosis, and the genes exhibited high diagnostic value. CONCLUSION: Expression levels of CRABP2, MMP12, and TOP2A in LUAD were higher than those in normal lung tissue. This observation has diagnostic value, and is linked to poor LUAD prognosis. These genes may be biomarkers and therapeutic targets in LUAD, but further research is warranted to investigate their usefulness in these respects.
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BACKGROUND: To investigate the incidence and risk factors of retinopathy of prematurity (ROP) in two Neonatal Intensive Care Units in North and South of China, respectively. METHODS: We studied data concerning 472 infants with gestational age (GA) ≤ 34 weeks or birth weight (BW) ≤ 2000 g who were admitted to the Zhujiang Hospital of Southern Medical University and the Fourth Hospital of Shijiazhuang between January 1, 2011 and December 31, 2011. Clinical information about perinatal neonates was collected and was confirmed by reviewing medical charts. The incidence and severity of ROP were assessed in the screened population. Main outcome measures are the incidence and severity of ROP. The relationship of clinical risk factors and the development of ROP were analyzed. RESULTS: The overall incidence of ROP was 12.7%, and the overall incidence of type 1 ROP was 2.3%; 9.4% of infants in Zhujiang Hospital had ROP compared to 15.0% infants in the Fourth Hospital of Shijiazhuang developed ROP, and the difference is statistically significant. ROP was significantly associated with GA (odds ratio [OR]: 0.77 [0.62-0.95], P = 0.015), BW (OR: 0.998 [0.996-0.999], P = 0.008), maternal supplemental oxygen administration before and during delivery (OR: 4.27 [1.21-15.10], P = 0.024) and preeclampsia (OR: 6.07 [1.73-21.36] P = 0.005). The risk factors for ROP are different in two hospitals. In Zhujiang Hospital, BW is the independent risk factors for ROP while GA, BW and preeclampsia in the Fourth Hospital in Shijiazhuang Conclusions: Retinopathy of prematurity incidence is different based on area. Incidence of ROP is still high in China. More efforts need to prevent ROP.
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Unidades de Terapia Intensiva Neonatal/estatística & dados numéricos , Retinopatia da Prematuridade/epidemiologia , China , Feminino , Humanos , Recém-Nascido , Masculino , Fatores de RiscoRESUMO
BACKGROUND: Depression is a frequent mood disorder that affects around a third of stroke patients and has been associated with poorer outcomes. Our aim was to determine whether there was a relationship between inflammatory markers (leptin) and post-stroke depression (PSD). METHODS: One hundred and ninety-one ischemic stroke patients admitted to the hospital within the first 24 hours after stroke onset were consecutively recruited and followed up for 3 months. Enzyme-linked immunosorbent assay (ELISA) was used to measure serum levels of leptin at admission. Based on the symptoms, diagnoses of depression were made in accordance with DSM-IV criteria for post-stroke depression at 3 month. RESULTS: Forty-four patients (23.0%) were diagnosed as having major depression at 3 month. Patients with depression showed higher serum leptin levels at 3 month after stroke (32.2 [IQR, 20.8-57.7] v. 9.9 [IQR, 4.6-13.1]ng/ml, respectively; Pâ=â0.000). Serum levels of leptin ≥20 ng/ml were independently associated with PSD [odds ratio (OR) 20.23, 95% confidence interval (CI) 9.11-51.26, Pâ=â 0.000], after adjusting for possible confounders. CONCLUSIONS: Serum leptin levels elevated at admission were found to be associated with PSD and may provide a new proposal for the treatment of PSD.
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Depressão/genética , Depressão/fisiopatologia , Leptina/sangue , Acidente Vascular Cerebral/genética , Idoso , Biomarcadores/sangue , Proteína C-Reativa/metabolismo , Estudos de Coortes , Depressão/sangue , Depressão/etiologia , Feminino , Estudos de Associação Genética , Humanos , Leptina/genética , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/fisiopatologiaRESUMO
Based on the characteristics of polycations of chitosan and glucoamylase, which are oppositely charged, they were successfully alternatingly deposited onto the surface of aldehyde-modified Fe3O4 nanoparticles by using a layer-by-layer ion exchange method to form magnetic carriers to construct multilayer films (designated as Fe3O4@(CS/GA)n). The (CS/GA)n film systems were endowed with the pH-dependent properties of chitosan as well as the catalytic activity of glucoamylase. The changes in weight loss and surface chemistry, morphology, and magnetic sensitivity were monitored and verified by UV/Vis spectroscopy, zeta potential, TEM, and a vibrating sample magnetometer. Subsequently, the influence of the number of bilayers, storage stability, pH, temperature, and reusability of Fe3O4@(CS/GA)5 biocatalysts on catalytic activity were investigated. The results from characterization and determination remarkably indicate that Fe3O4@(CS/GA)5 presents excellent catalytic activity, storage stability, pH stability, and reusability in comparison with free enzyme. Fe3O4@(CS/GA)5 retained >60% of its initial activity at 65 °C over 6 h; the optimum temperature and pH also increased to the ranges of 45-65 °C and 2.5-3.5, respectively, and only 27% activity was lost after 10 cycles. This new strategy simplifies the reaction protocol and improves encapsulation efficiency and catalytic activity for new potential applications in biotechnology.
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Quitosana/metabolismo , Glucana 1,4-alfa-Glucosidase/metabolismo , Nanopartículas de Magnetita/química , Biocatálise , Quitosana/química , Glucana 1,4-alfa-Glucosidase/química , Concentração de Íons de Hidrogênio , Íons/química , Íons/metabolismo , Tamanho da Partícula , Propriedades de SuperfícieRESUMO
OBJECTIVE: To analyze the stress distribution of bone around the dental implants with lateral immediate loading of different angles by three dimensional finite element. METHODS: An adult edentulous mandible was adopted for CT scanning. The CT image was imported to universal surgical integration system to establish a mandible three dimensional mesh model. The real shape of standard thread implant was simulated and the finite element model of mandible with dental implants for immediate loading was established. The models were immediately loaded with 150 N through the angle of 0 degrees, 10 degrees, 20 degrees, 30 degrees. The ANSYS 10.0 was used to analyze the Von Mises stress on the bone around dental implants. RESULTS: The accurate finite element model of mandible with dental implants for immediate loading was successfully established. The three dimensional finite element analytical results showed: Under axial load, the Von Mises stress of bone contact surface concentrated on the cortical bone of the implant cervix. The strain distribution was even, and centralized at the cortical bone of the implant cervix, cancellous bone of implant bottom and thread contact area. Under different lateral angle load, the Von Mises stress of bone contact surface also concentrated on the cortical bone of the implant cervix, but the maximum value was 4 times of the vertical loading, the strain distributed unevenly, mainly concentrated on the cortical bone of the implant cervix. With the load angle increased, the stress and the strain value also increased. CONCLUSION: When an axial force was immediately loaded, the stress value and the strain concentration value of bone interface around the dental implants are not apparently concentrated, the stress is distributed well. While a lateral force is loaded, the stress values and the strain concentration values of bone interface around the dental implants apparently increase and the strain are distributed unevenly.