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1.
Eur J Clin Microbiol Infect Dis ; 43(2): 259-268, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38032514

RESUMO

BACKGROUND: Enterococcus faecalis is a common cause of healthcare-associated infections. Its resistance to linezolid, the antibiotic of last resort for vancomycin-resistant enterococci, has become a growing threat in healthcare settings. METHODS: We analyzed the data of E. faecalis isolates from 26 medical institutions between 2018 and 2020 and performed univariate and multivariate logistic regression analyses to determine the independent predictors for linezolid-resistant E. faecalis (LREFs). Then, we used the artificial neural network (ANN) and logistic regression (LR) to build a prediction model for linezolid resistance and performed a performance evaluation and comparison. RESULTS: Of 12,089 E. faecalis strains, 755 (6.25%) were resistant to linezolid. Among vancomycin-resistant E. faecalis, the linezolid-resistant rate was 24.44%, higher than that of vancomycin-susceptible E. faecalis (p < 0.0001). Univariate and multivariate regression analyses showed that gender, age, specimen type, length of stay before culture, season, region, GDP (gross domestic product), number of beds, and hospital level were predictors of linezolid resistance. Both the ANN and LR models constructed in the study performed well in predicting linezolid resistance in E. faecalis, with AUCs of 0.754 and 0.741 in the validation set, respectively. However, synthetic minority oversampling technique (SMOTE) did not improve the prediction ability of the models. CONCLUSION: E. faecalis linezolid-resistant rates varied by specimen site, geographic region, GDP level, facility level, and the number of beds. At the same time, community-acquired E. faecalis with linezolid resistance should be monitored closely. We can use the prediction model to guide clinical medication and take timely prevention and control measures.


Assuntos
Enterococcus faecium , Infecções por Bactérias Gram-Positivas , Enterococos Resistentes à Vancomicina , Humanos , Linezolida/farmacologia , Linezolida/uso terapêutico , Enterococcus faecalis , Vancomicina/uso terapêutico , Big Data , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Infecções por Bactérias Gram-Positivas/microbiologia , Testes de Sensibilidade Microbiana
2.
J Nucl Cardiol ; 37: 101881, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38723886

RESUMO

OBJECTIVES: We sought to develop a novel deep learning (DL) workflow to interpret single-photon emission computed tomography (SPECT) wall motion. BACKGROUND: Wall motion assessment with SPECT is limited by image temporal and spatial resolution. Visual interpretation of wall motion can be subjective and prone to error. Artificial intelligence (AI) may improve accuracy of wall motion assessment. METHODS: A total of 1038 patients undergoing rest electrocardiogram (ECG)-gated SPECT and echocardiography were included. Using echocardiography as truth, a DL-model (DL-model 1) was trained to predict the probability of abnormal wall motion. Of the 1038 patients, 317 were used to train a DL-model (DL-model 2) to assess regional wall motion. A 10-fold cross-validation was adopted. Diagnostic performance of DL was compared with human readers and quantitative parameters. RESULTS: The area under the receiver operating characteristic curve (AUC) and accuracy (ACC) of DL model (AUC: .82 [95% CI: .79-.85]; ACC: .88) were higher than human (AUC: .77 [95% CI: .73-.81]; ACC: .82; P < .001) and quantitative parameter (AUC: .74 [95% CI: .66-.81]; ACC: .78; P < .05). The net reclassification index (NRI) was 7.7%. The AUC and accuracy of DL model for per-segment and per-vessel territory diagnosis were also higher than human reader. The DL model generated results within 30 seconds with operable guided user interface (GUI) and therefore could provide preliminary interpretation. CONCLUSIONS: DL can be used to improve interpretation of rest SPECT wall motion as compared with current human readers and quantitative parameter diagnosis.


Assuntos
Aprendizado Profundo , Tomografia Computadorizada de Emissão de Fóton Único , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Ecocardiografia/métodos , Curva ROC , Reprodutibilidade dos Testes , Eletrocardiografia , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/fisiopatologia
3.
Environ Sci Technol ; 57(40): 15193-15202, 2023 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-37747327

RESUMO

Residential biomass combustion in developing countries produces significant primary particulate matter (PM) emissions. Highly time-resolved aerosol mass spectrometry and aethalometer measurements were used to investigate the dynamic changes of emitted PM chemical composition from a typical improved stove burning with wood and crop straw in China. Combustion temperature and organic aerosol (OA) concentration increased quickly during the ignition stage. The flaming stage was characterized by high combustion temperature and high pollutant [including OA, black carbon (BC), inorganic salts, and polycyclic aromatic hydrocarbons (PAHs)] emissions, while the burnout stage is characterized by low combustion temperature and lower pollutant emissions. OA was the primary emitted species; emission factors of OA in the flaming stage were generally higher (24.5-792%) than those in the burnout stage. Mass spectral signatures of OA were obtained. The ratio of Cl-/OA for wood combustion (0.05 ± 0.01) is much lower than that from burning crop straw (0.32 ± 0.19). Hydrocarbon OA emissions dominated during the ignition and flaming stages. A high percentage of oxidized OA was emitted during the burnout stage. The relationship between PAHs and BC/OA emissions under different burning conditions was investigated, and PAHs may act as intermediate products in the conversion of OA to BC.


Assuntos
Poluentes Atmosféricos , Poluentes Ambientais , Hidrocarbonetos Policíclicos Aromáticos , Material Particulado/análise , Poluentes Atmosféricos/análise , Biomassa , Poluentes Ambientais/análise , Aerossóis/análise , Fuligem/análise
4.
J Environ Sci (China) ; 124: 544-556, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36182162

RESUMO

A hygroscopic tandem differential mobility analyser (H-TDMA) was used to observe the size-resolved hygroscopic characteristics of submicron particles in January and April 2018 in urban Beijing. The probability distribution of the hygroscopic growth factor (HGF-PDF) in winter and spring usually showed a bimodal pattern, with more hygroscopic mode (MH) being more dominant. The seasonal variation in particle hygroscopicity was related to the origin of air mass, which received polluted southerly air masses in spring and clean northwesterly air masses in winter. Particles showed stronger hygroscopic behaviour during heavy pollution episodes (HPEs) with elevated concentrations of secondary aerosols, especially higher mass fraction of nitrate, which were indicated using the PM2.5 (particulate matter with diameter below 2.5 µm) mass concentration normalised by CO mass concentration. The hygroscopic parameter (κ) values were calculated using H-TDMA (κhtdma) and chemical composition (κchem). The closure study showed that κchem was overestimated in winter afternoon when compared with κhtdma, because the organic particle hygroscopic parameter (κorg) was overestimated in the calculations. It was influenced by the presence of a high concentration of hydrocarbon-like organic aerosol (HOA) with a weak water uptake ability. A positive relationship was observed between κorg and the ratio of oxygenated organic aerosol (OOA) and HOA, thereby indicating that the strong oxidation state enhanced the hygroscopicity of the particles. This study revealed the effect of local emission sources and secondary aerosol formation processes on particle hygroscopicity, which is of great significance for understanding the pollution formation mechanism in the North China Plain.


Assuntos
Poluentes Atmosféricos , Nitratos , Aerossóis/análise , Poluentes Atmosféricos/análise , Pequim , China , Monitoramento Ambiental , Tamanho da Partícula , Material Particulado/análise , Estações do Ano , Água , Molhabilidade
5.
Environ Res ; 208: 112672, 2022 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-34999028

RESUMO

Regional transport is a key source of carbonaceous aerosol in many Chinese megacities including Beijing. The sources of carbonaceous aerosol in urban areas have been studied extensively but are poorly known in upwind rural areas. This work aims to quantify the contributions of fossil and non-fossil fuel emissions to carbonaceous aerosols at a rural site in North China Plain in winter 2016. We integrated online high resolution-time of flight-aerosol mass spectrometer (HR-TOF-AMS) observations and radiocarbon (14C) measurements of fine particles with Positive Matrix Factorization (PMF) analysis as well as Extended Gelencsér (EG) method. We found that fine particle concentration is much higher at the rural site than in Beijing during the campaign (Dec 7, 2016 to Jan 8, 2017). PMF analysis of the AMS data showed that coal-combustion related organic aerosol (CCOA + Oxidized CCOA) and more oxidized oxygenated organic aerosol (MO-OOA) contributed 48% and 30% of organic matter to non-refractory PM1 (NR-PM1) mass. About 2/3 of the OC and EC were from fossil-fuel combustion. The EG method, combining AMS-PMF and 14C data, showed that primary and secondary OC from fossil fuel contribute 35% and 22% to total carbon (TC), coal combustion emission dominates the fossil fuel sources, and biomass burning accounted for 21% of carbonaceous aerosol. In summary, our results confirm that fossil fuel combustion was the dominant source of carbonaceous aerosol during heavy pollution events in the rural areas. Significant emissions of solid fuel carbonaceous aerosols at rural areas can affect air quality in downwind cities such as Beijing and Tianjin, highlighting the benefits of energy transition from solid fuels to cleaner energy in rural areas.


Assuntos
Poluentes Atmosféricos , Material Particulado , Aerossóis/análise , Poluentes Atmosféricos/análise , Carbono/análise , China , Monitoramento Ambiental/métodos , Combustíveis Fósseis , Fósseis , Material Particulado/análise , Estações do Ano
6.
Neoplasma ; 69(6): 1338-1348, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36305690

RESUMO

Gastric carcinoma (GC) is the fourth most common malignancy worldwide and the second cause of death of all malignancies worldwide. AMPK catalytic subunit α1 (PRKAA1) is involved in various types of cancer and PRKAA1 knockdown significantly decreased the invasiveness of GC cells. Fat mass and obesity-associated protein (FTO)-regulation of m6A has been shown to be involved in different diseases including cancer. However, the role of PRKAA1 and m6A modification in GC remains to be elucidated. PRKAA1 was silenced or overexpressed to study the role of PRKAA1 in regulating cell viability, colony formation, and glycolysis. Levels of lactic acid, GSH, and NADP+/NADPH were measured using commercial kits. Extracellular acidification rates were determined by an extracellular flux analyzer. RNA immunoprecipitation was performed to test m6A levels and the interaction between PRKAA1-3'-UTR and YTHDF2. Quantitative RT-PCR and immunoblots were applied to measure mRNA or protein levels, respectively. PRKAA1 silencing inhibited cell growth, colony formation, and glycolysis but enhanced apoptosis, while the PRKAA1 overexpression promoted cell growth, colony formation, and glycolysis but inhibited apoptosis of GC cells. Data also indicated that PRKAA1 regulated cell growth and apoptosis by regulating the redox balance. Mechanism study demonstrated that FTO regulated PRKAA1 mRNA m6A modification and stability. Clinical samples analysis demonstrated that PRKAA1 and FTO expression were increased in GC patients and positively correlated with each other. FTO increased levels of PRKAA1 by regulating its mRNA m6A modification and stability. PRKAA1, in turn, promoted cell viability, colony formation, and glycolysis but inhibited apoptosis of GC cells by promoting the redox balance.


Assuntos
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/patologia , Proliferação de Células , Fatores de Transcrição/metabolismo , Oxirredução , RNA Mensageiro/metabolismo , Glicólise , Proteínas Quinases Ativadas por AMP/genética , Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética , Dioxigenase FTO Dependente de alfa-Cetoglutarato/metabolismo , Proteínas de Ligação a RNA/metabolismo
7.
Environ Sci Technol ; 54(3): 1344-1352, 2020 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-31766848

RESUMO

The Beijing government implemented a number of clean air action plans to improve air quality in the last 10 years, which contributed to changes in the concentration of fine particles and their compositions. However, quantifying the impacts of these interventions is challenging as meteorology masks the real changes in observed concentrations. Here, we applied a machine learning technique to decouple the effect of meteorology and evaluate the changes in the chemistry of nonrefractory PM1 (particulate matter less than 1 µm) in winter 2007, 2016, and 2017 as a result of the clean air actions. The observed mass concentrations of PM1 were 74.6, 90.2, and 36.1 µg m-3 in the three winters, while the deweathered concentrations were 74.2, 78.7, and 46.3 µg m-3, respectively. The deweathered concentrations of PM1, organics, sulfate, ammonium, chloride, SO2, NO2, and CO decreased by -38, -46, -59, -24, -51, -89, -16, and -52% in 2017 in comparison to 2007. On the contrary, the deweathered concentration of nitrates increased by 4%. Our results indicate that the clean air actions implemented in 2017 were highly effective in reducing ambient concentrations of SO2, CO, and PM1 organics, sulfate, ammonium, and chloride, but the control of nitrate and PM1 organics remains a major challenge.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Pequim , China , Monitoramento Ambiental , Tamanho da Partícula , Material Particulado
8.
Biochem Biophys Res Commun ; 503(2): 870-875, 2018 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-29928882

RESUMO

Recently, circular RNA (circRNA) is identified as a novel class of noncoding RNA with important roles in human diseases, such as cancer. However, how circRNA participates in colorectal cancer (CRC) remains unclear. In this study, we aimed to illustrate the role of circ_0026344 in CRC progression. We showed that circ_0026344 expression was downregulated in CRC tissues compared to adjacent normal tissues. Moreover, the level of circ_0026344 was inversely correlated with CRC advance and lymphoid node metastasis. Additionally, circ_0026344 low expression predicted poor prognosis in CRC patients. We identified circ_0026344 as a miRNA sponge for microRNA-21 (miR-21) and microRNA-31 (miR-31) whose expression levels were elevated in CRC tissues. And the level of circ_0026344 was reversely correlated with both miR-21 and miR-31 levels in CRC tissues. Functionally, we found that ectopic expression of circ_0026344 decreased the growth and invasion of CRC cells while promoting apoptosis in vitro. The xenograft experiment indicated that circ_0026344 overexpress led to CRC growth inhibition in vivo. Rescue assays further demonstrated that circ_0026344 exerted biological functions by sponging miR-21 and miR-31 in CRC. In conclusion, this study revealed that circ_0026344/miR-21/miR-31 regulatory signaling was implicated in CRC progression.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Colorretais/genética , MicroRNAs/genética , RNA Neoplásico/genética , RNA/genética , Animais , Sequência de Bases , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Células HCT116 , Células HEK293 , Células HT29 , Humanos , Camundongos Nus , Prognóstico , RNA Circular , Homologia de Sequência do Ácido Nucleico , Transplante Heterólogo
9.
Mar Drugs ; 15(11)2017 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-29125577

RESUMO

Anandins A (1) and B (2), two rare steroidal alkaloids, were isolated from the fermentative broth of a marine actinobacteria Streptomyces anandii H41-59. The gross structures of the two alkaloids were elucidated by spectroscopic methods including HR-ESI-MS, and NMR. Their absolute configurations were confirmed by single-crystal X-ray diffraction analysis and comparison of their experimental and calculated electronic circular dichroism spectra, respectively. Anandin A exhibited a moderate inhibitory effect against three human cancer cell lines MCF-7, SF-268, and NCI-H460 with IC50 values of 7.5, 7.9, 7.8 µg/mL, respectively.


Assuntos
Alcaloides/química , Esteroides/química , Streptomyces/metabolismo , Alcaloides/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Organismos Aquáticos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Modelos Moleculares , Esteroides/farmacologia
10.
Molecules ; 22(4)2017 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-28333094

RESUMO

The bulbs of Lilium brownii var. viridulum (LB) are commonly used as both traditional Chinese medicines and popular functional food for many centuries in China. Previous studies reported that the extract of lily bulbs exhibited anti-inflammatory activity both in vivo and in vitro, but its active components and associated molecular mechanisms remain elusive. In the present study, using bioassay-guided isolation method, two phenylpropenoid acylglycerols, 1-O-feruloyl-2-O-p-coumaroylglycerol (1) and 1,3-O-diferuloylglycerol (2), were obtained and identified from the chloroform fraction of LB. Both compounds 1 and 2 significantly decreased the production of nitrite oxide (NO) in lipopolysaccharide (LPS)-stimulated mouse macrophage RAW264.7 cells in a dose-dependent manner with half maximal inhibitory concentration (IC50) values of 9.12 ± 0.72 µM and 12.01 ± 1.07 µM, respectively. They also inhibited the production of prostaglandin E2 (PGE2) and several other pro-inflammatory cytokines, such as interleukin-1ß (IL-1ß), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α). Furthermore, compounds 1 and 2 downregulated the protein levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). They also inhibited the nuclear translocation of nuclear factor-κB (NF-κB) p65 subunit and suppressed mitogen-activated protein kinases (MAPKs) pathway. Taken these data together, compounds 1 and 2 exhibited anti-inflammatory activities through acting on the NF-κB and MAPKs pathway. This research provides the first evidence on the major bioactive constituents and related molecular mechanisms of LB as an anti-inflammatory agent. Our findings also advanced the understanding of LB as a traditional herbal medicine for the prevention and treatment of inflammation.


Assuntos
Anti-Inflamatórios/isolamento & purificação , Lilium/química , NF-kappa B/metabolismo , Extratos Vegetais/isolamento & purificação , Raízes de Plantas/química , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Óxido Nítrico/metabolismo , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Células RAW 264.7
11.
J Nat Prod ; 79(1): 196-203, 2016 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-26741483

RESUMO

During an ongoing exploration of potential anti-inflammatory agents from medicinal plants, eight new arylalkenyl α,ß-unsaturated δ-lactones, cryptoconcatones A-H (1-8), and two unusual arylalkenyl α,ß-unsaturated γ-lactones, cryptoconcatones I and J (9 and 10), were identified from the leaves and twigs of Cryptocarya concinna. The structures of these compounds were established based on spectroscopic data (MS, 1D/2D NMR), and their absolute configurations were determined with Riguera's method, the modified Mosher's method, chemical derivatization, and the Snatzke chirality rule. Compounds 4-6 and 8-10 showed inhibitory activity toward nitric oxide (NO) production in lipopolysaccharide-induced RAW 264.7 macrophages, particularly compounds 4 and 8-10, with IC50 values of 3.2, 4.2, 3.4, and 7.5 µM, respectively.


Assuntos
Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Cryptocarya/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/farmacologia , Lactonas/isolamento & purificação , Lactonas/farmacologia , Animais , Anti-Inflamatórios/química , Medicamentos de Ervas Chinesas/química , Lactonas/química , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Camundongos , Estrutura Molecular , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/biossíntese , Ressonância Magnética Nuclear Biomolecular , Componentes Aéreos da Planta/química , Estereoisomerismo
12.
Mar Drugs ; 14(5)2016 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-27153073

RESUMO

An actinomycete strain, H41-59, isolated from sea sediment in a mangrove district, was identified as Streptomyces anandii on the basis of 16S rDNA gene sequence analysis as well as the investigation of its morphological, physiological and biochemical characteristics. Three new ergosterols, ananstreps A-C (1-3), along with ten known ones (4-13), were isolated from the culture broth of this strain. The gross structures of these new compounds were elucidated on the basis of extensive analysis of spectroscopic data, including HR-ESI-MS, and NMR. The cytotoxicities of these isolates against human breast adenocarcinoma cell line MCF-7, human glioblastoma cell line SF-268, and human lung cancer cell line NCI-H460 and their antibacterial activities in inhibiting the growth of Candida albicans and some other pathogenic microorganisms were tested. Compounds 3-8, 10 and 11 displayed cytotoxicity with IC50 values in a range from 13.0 to 27.8 µg/mL. However, all the tested compounds showed no activity on C. albicans and other bacteria at the test concentration of 1 mg/mL with the paper disc diffusion method.


Assuntos
Ergosterol/química , Streptomyces/química , Antibacterianos/química , Antibacterianos/farmacologia , Candida albicans/efeitos dos fármacos , Linhagem Celular Tumoral , Ergosterol/farmacologia , Sedimentos Geológicos/microbiologia , Humanos , Células MCF-7 , Espectroscopia de Ressonância Magnética/métodos , Testes de Sensibilidade Microbiana/métodos , RNA Ribossômico 16S/genética , Streptomyces/genética
13.
Zhong Yao Cai ; 39(3): 559-61, 2016 Mar.
Artigo em Zh | MEDLINE | ID: mdl-30088886

RESUMO

Objective: To study the non-alkaloid chemical constituents of Macleaya cordata. Methods: Alcohol extraction and liquidliquid partitionmethods were used to extract the chemical constituents. Silica gel,reverse-phase octadecylsilyl( ODS), and Sephadex LH-20 column chromatographic methods were applied for isolation and purification. Spectroscopic methods including MS and NMR were used to determine their structures. Results: Eleven non-alkaloid compounds were isolated from the fruits of Macleaya cordata, and their structures were identified as 3-( 3,4-dihydroxy) phenylpropanoic acid methyl ester( 1),ferulic acid( 2),1-octacosanol( 3),syringic acid( 4),p-hydroxy-benzoic acid( 5),p-coumaric acid( 6),quercetin-3-O-ß-D-glucoside( 7),N-p-coumaroyl tyramine( 8),10-eicosenoic acid( 9) and ß-sitosterol( 10) and daucosterol( 11). Conclusion: Compounds 1,3 ~9 are isolated from Macleaya cordata for the first time.


Assuntos
Papaveraceae , Alcaloides , Ácidos Cumáricos , Ácido Gálico/análogos & derivados , Glucosídeos , Quercetina , Sitosteroides , Tiramina/análogos & derivados
14.
Indian J Microbiol ; 56(4): 445-450, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27784941

RESUMO

Superoxide dismutase (SOD) and catalase are considered the most important antioxidant enzymes which protect fungus from the oxidant damage of reactive oxygen species. In this study, we collected 44 strains of Trichosporon asahii (T. asahii) from different sources and investigated their SOD and catalase activities. The results showed that the SOD and catalase activities of Clinical group were significantly higher than those of Environment group (p < 0.01). The SOD and catalase activities of T. asahii in Internal passage group went up gradually after passage in mice, and were significantly higher in 5th generation of Internal passage group (p < 0.05). The SOD and catalase activities of Fluconazole-resistant group strains also increased after resistant induction, and the SOD and catalase activities were significantly higher in the 10th generation of Fluconazole-resistant group (p < 0.05). This implied that T. asahii has stronger antioxidant ability. The strains of T. asahii from different sources have different antioxidant abilities, which mainly manifest in the difference of antioxidant enzymatic activities. Clinical group strains have the strongest antioxidant capacity; Internal passage group strains and Fluconazole resistant group strains better; Environmental group strains the lowest. These results also suggested that the antioxidant defensive response of T. asahii might be relevant to its infection mechanism and drug resistance mechanism.

15.
Chemistry ; 21(38): 13206-9, 2015 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-26228004

RESUMO

Involucratustones A-C (1-3), three cadinane dimers containing multiple contiguous quaternary carbons, were isolated from the rhizomes of Stahlianthus involucratus. Their structures were determined by a combination of NMR spectroscopy, chemical conversion, and X-ray diffraction analysis. Compounds 1 and 2 are rearranged homodimers of cadinane sesquiterpene fused with a unique fully substituted 1-oxaspiro[4.4]nonane core observed for the first time in natural products, and 3 is a novel 3',4'-seco-cadinane-dimer. Compounds 1 and 2 exhibited potent cytotoxic activities, and 3 showed notable anti-inflammatory effect.


Assuntos
Produtos Biológicos/química , Sesquiterpenos/química , Compostos de Espiro/química , Produtos Biológicos/isolamento & purificação , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Sesquiterpenos/isolamento & purificação , Difração de Raios X
16.
Org Biomol Chem ; 13(27): 7452-8, 2015 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-26062044

RESUMO

A total of 14 new diterpene dimers, aphanamenes C-P ()1-14, with four known homologous compounds were isolated from the root barks of Aphanamixis grandifolia Bl. The structures of these compounds were elucidated by spectroscopic analyses, and their absolute configurations were determined using the CD exciton chirality method. In addition, all the compounds exhibited significant inhibition of lipopolysaccharide-induced nitric oxide production in RAW264.7 macrophages, with IC50 values between 7.75 and 38.23 µM.


Assuntos
Anti-Inflamatórios/farmacologia , Dimerização , Diterpenos/farmacologia , Meliaceae/química , Casca de Planta/química , Raízes de Plantas/química , Animais , Anti-Inflamatórios/síntese química , Anti-Inflamatórios/química , Bioensaio , Vias Biossintéticas/efeitos dos fármacos , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Morte Celular/efeitos dos fármacos , Dicroísmo Circular , Diterpenos/síntese química , Diterpenos/química , Camundongos , Espectroscopia de Prótons por Ressonância Magnética , Células RAW 264.7 , Estereoisomerismo
17.
Chem Pharm Bull (Tokyo) ; 63(3): 237-43, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25757495

RESUMO

Nine new tirucallane-type triterpenoids, ficutirucins A-I (1-9), were isolated from the fruit of Ficus carica. Their structures were established on the basis of spectroscopic data and chemical methods. All isolates were evaluated for their cytotoxic activities against three human cancer cell lines, MCF-7, HepG-2, and U2OS. Compounds 1-3, 6, 7, and 9 exhibited moderate cytotoxic activities with IC50 values of 11.67-45.61 µM against one or more of the three cancer cell lines.


Assuntos
Citotoxinas/isolamento & purificação , Ficus , Frutas , Extratos Vegetais/isolamento & purificação , Triterpenos/isolamento & purificação , Citotoxinas/química , Citotoxinas/farmacologia , Células Hep G2 , Humanos , Células MCF-7 , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Triterpenos/química , Triterpenos/farmacologia
18.
J Environ Sci (China) ; 26(1): 205-13, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24649708

RESUMO

Trace metals in PM2.5 were measured at one industrial site and one urban site during September, 2010 in Ji'nan, eastern China. Individual aerosol particles and PM2.5 samples were collected concurrently at both sites. Mass concentrations of eleven trace metals (i.e., Al, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Sr, Ba, and Pb) and one metalloid (i.e., As) were measured by inductively coupled plasma atomic emission spectroscopy (ICP-AES). The result shows that mass concentrations of PM2.5 (130 microg/m3) and trace metals (4.03 microg/m3) at the industrial site were 1.3 times and 1.7 times higher than those at the urban site, respectively, indicating that industrial activities nearby the city can emit trace metals into the surrounding atmosphere. Fe concentrations were the highest among all the measured trace metals at both sites, with concentrations of 1.04 microg/m 3 at the urban site and 2.41 microg/m3 at the industrial site, respectively. In addition, Pb showed the highest enrichment factors at both sites, suggesting the emissions from anthropogenic activities existed around the city. Correlation coefficient analysis and principal component analysis revealed that Cu, Fe, Mn, Pb, and Zn were originated from vehicular traffic and industrial emissions at both sites; As, Cr, and part of Pb from coal-fired power plant; Ba and Ti from natural soil. Based on the transmission electron microscopy analysis, we found that most of the trace metals were internally mixed with secondary sulfate/organic particles. These internally mixed trace metals in the urban air may have different toxic abilities compared with externally mixed trace metals.


Assuntos
Metais Pesados/análise , Material Particulado/análise , Alumínio/análise , China , Cidades , Metais Pesados/toxicidade , Microscopia Eletrônica de Transmissão , Material Particulado/toxicidade , Análise de Componente Principal
19.
J Glob Antimicrob Resist ; 36: 453-459, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37918787

RESUMO

OBJECTIVES: Carbapenem-resistant Klebsiella pneumoniae (CRKP) is a serious threat to public health due to its limited treatment options and high mortality rate. This study aims to identify the risk factors of carbapenem resistance in patients with K. pneumoniae isolates and develop CRKP prediction models using logistic regression (LR) and artificial neural network (ANN) methods. METHODS: We retrospectively analysed the data of 49,774 patients with Klebsiella pneumoniae isolates from a regional nosocomial infection surveillance system (RNSS) between 2018 and 2021. We performed logistic regression analyses to determine the independent predictors for CRKP. We then built and evaluated LR and ANN models based on these predictors using calibration curves, ROC curves, and decision curve analysis (DCA). We also applied the Synthetic Minority Over-Sampling Technique (SMOTE) to balance the data of CRKP and non-CRKP groups. RESULTS: The LR model showed good discrimination and calibration in both training and validation sets, with areas under the ROC curve (AUROC) of 0.824 and 0.825, respectively. The DCA indicated that the LR model had clinical usefulness for decision making. The ANN model outperformed the LR model both in the training set and validation set. The SMOTE technique improved the performance of both models for CRKP detection in training set, but not in the validation set. CONCLUSION: We developed and validated LR and ANN models for predicting CRKP based on RNSS data. Both models were feasible and reliable for CRKP inference and could potentially assist clinicians in selecting appropriate empirical antibiotics and reducing unnecessary medical resource utilization.


Assuntos
Enterobacteriáceas Resistentes a Carbapenêmicos , Infecção Hospitalar , Infecções por Klebsiella , Humanos , Klebsiella pneumoniae , Carbapenêmicos/farmacologia , Carbapenêmicos/uso terapêutico , Estudos Retrospectivos , Modelos Logísticos , Infecções por Klebsiella/tratamento farmacológico , Infecção Hospitalar/tratamento farmacológico , China/epidemiologia
20.
Atherosclerosis ; 395: 117574, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38797614

RESUMO

BACKGROUND AND AIMS: Albuminuria is an established risk factor for adverse cardiovascular outcomes. However, few studies have characterized longitudinal albuminuria patterns based on long-term measurement of urine albumin-to-creatinine ratio (UACR) levels. We aimed to evaluate the association between longitudinal albuminuria patterns in midlife adults and subsequent CAC progression. METHODS: We included 1919 participants with CAC assessment by computed tomography from CARDIA (Coronary Artery Risk Development in Young Adults) study. CAC progression was determined for each individual as the difference of logarithmic CAC scores at follow-up and baseline. Albuminuria patterns across a 10-year span were estimated by longitudinal UACR levels. Multivariable general linear models were used to evaluate the association of long-term albuminuria patterns with CAC progression. RESULTS: Of the 1919 included participants, 583 (30.4 %) participants experienced CAC progression, and the mean (SD) age was 50.4 (3.5) years at year 25. A total of four dynamic albuminuria patterns were identified. After multivariable adjustment, there were significant differences in CAC progression by albuminuria patterns as demonstrated as percent change in CAC with 36.0 % (SE, 1.5) progression for mid- and late-life normoalbuminuria group, 46.0 % (SE, 7.6) for midlife normoalbuminuria and late-life high albuminuria group, 52.4 % (SE, 7.1) for midlife high albuminuria and late-life normoalbuminuria group, and 54.5 % (SE, 8.7) for mid- and late-life high albuminuria group (p = 0.019). Similar findings were also observed in CAC volume score changes. CONCLUSIONS: Longitudinal albuminuria patterns across a 10-year span were associated with worse CAC progression independent of baseline CAC level and albuminuria changes, suggesting that it may provide early identification of high-risk individuals with dynamic rises in albuminuria who may benefit from aggressive risk factor modification.


Assuntos
Albuminúria , Doença da Artéria Coronariana , Progressão da Doença , Calcificação Vascular , Humanos , Albuminúria/epidemiologia , Masculino , Feminino , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/diagnóstico por imagem , Pessoa de Meia-Idade , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/epidemiologia , Adulto , Estudos Longitudinais , Fatores de Risco , Medição de Risco , Estados Unidos/epidemiologia , Adulto Jovem , Fatores de Tempo , Angiografia por Tomografia Computadorizada , Creatinina/urina , Angiografia Coronária , Estudos Prospectivos , Valor Preditivo dos Testes , Fatores Etários , Adolescente
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