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1.
Proc Natl Acad Sci U S A ; 118(10)2021 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-33649215

RESUMO

Surface ozone is a severe air pollution problem in the North China Plain, which is home to 300 million people. Ozone concentrations are highest in summer, driven by fast photochemical production of hydrogen oxide radicals (HOx) that can overcome the radical titration caused by high emissions of nitrogen oxides (NOx) from fuel combustion. Ozone has been very low during winter haze (particulate) pollution episodes. However, the abrupt decrease of NOx emissions following the COVID-19 lockdown in January 2020 reveals a switch to fast ozone production during winter haze episodes with maximum daily 8-h average (MDA8) ozone concentrations of 60 to 70 parts per billion. We reproduce this switch with the GEOS-Chem model, where the fast production of ozone is driven by HOx radicals from photolysis of formaldehyde, overcoming radical titration from the decreased NOx emissions. Formaldehyde is produced by oxidation of reactive volatile organic compounds (VOCs), which have very high emissions in the North China Plain. This remarkable switch to an ozone-producing regime in January-February following the lockdown illustrates a more general tendency from 2013 to 2019 of increasing winter-spring ozone in the North China Plain and increasing association of high ozone with winter haze events, as pollution control efforts have targeted NOx emissions (30% decrease) while VOC emissions have remained constant. Decreasing VOC emissions would avoid further spreading of severe ozone pollution events into the winter-spring season.


Assuntos
Poluição do Ar/análise , Ozônio/análise , Material Particulado/análise , Estações do Ano , Compostos Orgânicos Voláteis , COVID-19 , China , Produtos Agrícolas , Monitoramento Ambiental , Poluição Ambiental , Humanos , Óxidos de Nitrogênio/química , Pandemias , Saúde Pública
2.
Proc Natl Acad Sci U S A ; 118(8)2021 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-33593919

RESUMO

Secondary organic aerosol (SOA) produced by atmospheric oxidation of primary emitted precursors is a major contributor to fine particulate matter (PM2.5) air pollution worldwide. Observations during winter haze pollution episodes in urban China show that most of this SOA originates from fossil-fuel combustion but the chemical mechanisms involved are unclear. Here we report field observations in a Beijing winter haze event that reveal fast aqueous-phase conversion of fossil-fuel primary organic aerosol (POA) to SOA at high relative humidity. Analyses of aerosol mass spectra and elemental ratios indicate that ring-breaking oxidation of POA aromatic species, leading to functionalization as carbonyls and carboxylic acids, may serve as the dominant mechanism for this SOA formation. A POA origin for SOA could explain why SOA has been decreasing over the 2013-2018 period in response to POA emission controls even as emissions of volatile organic compounds (VOCs) have remained flat.

3.
Proc Natl Acad Sci U S A ; 116(39): 19288-19293, 2019 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-31501346

RESUMO

Bacterial cellulose nanofiber (BCNF) with high thermal stability produced by an ecofriendly process has emerged as a promising solution to realize safe and sustainable materials in the large-scale battery. However, an understanding of the actual thermal behavior of the BCNF in the full-cell battery has been lacking, and the yield is still limited for commercialization. Here, we report the entire process of BCNF production and battery manufacture. We systematically constructed a strain with the highest yield (31.5%) by increasing metabolic flux and improved safety by introducing a Lewis base to overcome thermochemical degradation in the battery. This report will open ways of exploiting the BCNF as a "single-layer" separator, a good alternative to the existing chemical-derived one, and thus can greatly contribute to solving the environmental and safety issues.

4.
Clin Lab ; 67(11)2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34758229

RESUMO

BACKGROUND: Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) started to spread in Daegu beginning at the end of February 2020. IgG and IgM antibodies against SARS-CoV-2 were measured in hospitalized patients with COVID-19 with moderate to severe symptoms to improve the understanding of antibody responses. METHODS: We enrolled 312 patients with COVID-19 admitted to seven hospitals located in Daegu. Using serum (or plasma) samples from patients with polymerase chain reaction (PCR)-confirmed SARS-CoV-2 infections, both IgG and IgM antibodies were measured using commercial enzyme-linked immunosorbent assay (R-FIND CO¬VID-19 ELISA, SG medical, Seoul, Korea). RESULTS: The median value from the initial diagnosis, confirmed by SARS-CoV-2 PCR, to the sampling date was 24 days (day 1 to 88). The total positive rate of IgG was 93.9% and the positive IgM rate was 39.4%, without considering the elapsed period after diagnosis. Positive IgG and IgM rates were highest at 100.0% and 59.0%, respectively, at 3 weeks (15 - 21 days). IgG showed a high positive rate of 79.3% even within 7 days after the initial diag-nosis of the disease and maintained a positive rate of 97.8% until after 8 weeks. CONCLUSIONS: Among hospitalized patients with COVID-19, IgG was detected from the beginning of the diagnosis and persisted for an extended time period.


Assuntos
COVID-19 , Anticorpos Antivirais , Formação de Anticorpos , Ensaio de Imunoadsorção Enzimática , Humanos , Imunoglobulina G , Imunoglobulina M , República da Coreia , SARS-CoV-2 , Sensibilidade e Especificidade
5.
Eur Respir J ; 48(4): 1184-1191, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27587543

RESUMO

We evaluated the associations between potentially functional variants in a comprehensive list of cancer-related genes and lung cancer in a Korean population.A total of 1969 potentially functional single nucleotide polymorphisms (SNPs) of 1151 genes involved in carcinogenesis were evaluated using an Affymetrix custom-made GeneChip in 610 nonsmall cell lung cancer patients and 610 healthy controls. A replication study was conducted in an independent set of 490 cases and 486 controls. 68 SNPs were significantly associated with lung cancer in the discovery set and tested for replication.Among the 68 SNPs, three SNPs (corepressor interacting with RBPJ 1 (CIR1) rs13009079T>C, ribonucleotide reductase M1 (RRM1) rs1465952T>C and solute carrier family 38, member 4 (SLC38A4) rs2429467C>T) consistantly showed significant associations with lung cancer in the replication study. In combined analysis, adjusted odds ratio for CIR1 rs13009079T>C, RRM1 rs1465952T>C and SLC38A4 rs2429467C>T were 0.69, 0.71 and 0.73, respectively (p=4×10-5, 0.01 and 0.001, respectively) under the dominant model. The relative mRNA expression level of CIR1 was significantly associated with rs13009079T>C genotypes in normal lung tissues (ptrend=0.03).These results suggest that the three SNPs, particularly CIR1 rs13009079T>C, may play a role in the pathogenesis of lung cancer.


Assuntos
Neoplasias Pulmonares/genética , Polimorfismo de Nucleotídeo Único , Idoso , Sistema A de Transporte de Aminoácidos/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Estudos de Casos e Controles , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas Repressoras/genética , República da Coreia , Ribonucleosídeo Difosfato Redutase , Proteínas Supressoras de Tumor/genética
6.
J Hepatol ; 63(2): 486-93, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25772036

RESUMO

BACKGROUND & AIMS: Although sarcopaenia is associated with obesity-related comorbidities, its influence on non-alcoholic fatty liver disease (NAFLD) or steatohepatitis has not been fully determined. We aimed to investigate the direct relationship between sarcopaenia and NAFLD or steatohepatitis in the general population. METHODS: We conducted a cross-sectional study using nationally representative samples of 15,132 subjects from the Korea National Health and Nutrition Examination Surveys 2008-2011. Subjects were defined as having NAFLD when they had higher scores from previously validated NAFLD prediction models such as the hepatic steatosis index, comprehensive NAFLD score and NAFLD liver fat score. BARD and FIB-4 scores were used to define advanced fibrosis in subjects with NAFLD. The skeletal muscle index (SMI) [SMI(%)=total appendicular skeletal muscle mass (kg)/weight (kg)×100] measured by dual-energy X-ray absorptiometry was used to diagnose sarcopaenia with cut points of 32.2% for men and 25.5% for women. RESULTS: SMI was inversely correlated with all NAFLD predicting scores (Ps<0.001). After stratification, sarcopaenic subjects had an increased risk of NAFLD regardless of obesity (odds ratios [ORs]=1.55 to 3.02, depending on models; all Ps<0.001) or metabolic syndrome (ORs=1.63 to 4.00, all Ps<0.001). Multiple logistic regression analysis also demonstrated this independent association between sarcopaenia and NAFLD after adjusting for confounding factors related to obesity or insulin resistance (ORs=1.18 to 1.22, all Ps<0.001). Furthermore, among the NAFLD population, subjects with lower SMIs were likely to have advanced fibrosis compared with non-sarcopaenic individuals (BARD and FIB-4: ORs=1.83 and 1.69, respectively; both Ps<0.001). Compared with non-exercised subjects, individuals who exercised regularly had a lower risk of NAFLD (p<0.001), particularly among obese people with well-preserved muscle mass. CONCLUSIONS: Sarcopaenia is associated with increased risks of NAFLD and advanced fibrosis, independent of obesity or metabolic control.


Assuntos
Resistência à Insulina , Hepatopatia Gordurosa não Alcoólica/etiologia , Obesidade/etiologia , Sarcopenia/complicações , Absorciometria de Fóton , Índice de Massa Corporal , Estudos Transversais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/metabolismo , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Obesidade/diagnóstico , Obesidade/epidemiologia , Prevalência , Prognóstico , República da Coreia/epidemiologia , Estudos Retrospectivos , Sarcopenia/diagnóstico , Sarcopenia/epidemiologia
7.
Am Heart J ; 170(4): 760-769.e2, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26386800

RESUMO

BACKGROUND: A substantial percentage of patients have undiagnosed diabetes. We investigated the demographic characteristics and cardiometabolic profiles of subjects with undiagnosed diabetes. METHODS: A cross-sectional study with nationally representative samples of 25490 subjects aged ≥ 20 years from the KHNANES 2008 to 2011, which applied a complex, multistage, probability proportional to size sampling design. Subjects were categorized as having normal glucose (n = 16880), impaired fasting glucose (n = 5771), undiagnosed diabetes (n = 713), or diagnosed diabetes (n = 2126). Hyper low-density lipoprotein cholesterolemia was individually evaluated by the 2004 Adult Treatment Panel III guidelines and predicted risk of cardiovascular disease was estimated from the Framingham model. RESULTS: Among overall subjects with diabetes, the prevalence of undiagnosed diabetes was markedly increased in younger adults compared to older adults (49% in diabetic subjects <50 years vs 23% in diabetic subjects ≥50 years, P < .001), suggesting significant discrepancies in age-based screening. Patients with undiagnosed diabetes were also more likely to have undiagnosed or uncontrolled hypertension and hyper-low-density lipoprotein cholesterolemia. Individuals with undiagnosed diabetes had a significantly higher predicted 10-year Framingham cardiovascular disease risk than those with diagnosed diabetes (11% vs 8% in <50 years, 33% vs 30% in ≥50 years; both P < .001). Patients with undiagnosed diabetes were also more likely to have multiple cardiovascular risk factors including obesity, smoking and uncontrolled hypertension. CONCLUSIONS: People with undiagnosed diabetes have a higher predicted risk for cardiovascular disease compared to those with diagnosed diabetes. Intensive screening for diabetes in younger adults should be stressed in public healthcare to reduce the burden of modifiable cardiometabolic risk among individuals with undiagnosed diabetes.


Assuntos
Doenças Cardiovasculares/epidemiologia , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiologia , Adulto , Glicemia/metabolismo , Doenças Cardiovasculares/etiologia , Estudos Transversais , Diabetes Mellitus/sangue , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prevalência , República da Coreia/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
8.
Cardiovasc Diabetol ; 14: 53, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-25975731

RESUMO

BACKGROUND: We investigated the relationship between the glycemic indices glycated albumin (GA) and glycated hemoglobin (HbA1c) and the progression of diabetic vascular complications [diabetic nephropathy (DN) and carotid artery atherosclerosis (CAA)] in subjects with type 1 diabetes (T1D). METHODS: A total of 154 participants with a median follow-up of 2.8 years were enrolled in this retrospective longitudinal study. We recruited T1D subjects who had regularly measured urine albumin-creatinine ratios and estimated glomerular filtration rates, as well as tested HbA1c and GA levels consecutively every 3 or 6 months. A subgroup of 54 subjects was measured repeated carotid intima-media thickness (IMT). RESULTS: We classified subjects into the DN progression (Group I; n = 30) with either deteriorated stages of chronic kidney disease (n = 18) or albuminuria progression (n = 17), and the non-progression (Group II; n = 124). In multiple logistic regression analyses, baseline albuminuria (odds ratio [OR] = 2.64, 95 % confidence interval [CI] = 1.03-6.74), mean GA levels (OR = 2.03, 95 % CI = 1.27-3.26) were significantly associated with progression of DN. However, there was no association with mean HbA1c (OR = 0.98, 95 % CI = 0.62-1.54). In a subgroup analysis for follow-up measurements of carotid IMT, age was independently associated with the presence of plaque and the mean IMT. However glycemic indices were not significantly associated with CAA. CONCLUSIONS: Mean GA levels were more closely associated with DN progression than mean HbA1c in subjects with T1D. However, they were not associated with the CAA.


Assuntos
Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/diagnóstico , Angiopatias Diabéticas/sangue , Angiopatias Diabéticas/diagnóstico , Microvasos/metabolismo , Albumina Sérica/metabolismo , Adulto , Idoso , Espessura Intima-Media Carotídea/tendências , Diabetes Mellitus Tipo 1/epidemiologia , Angiopatias Diabéticas/epidemiologia , Feminino , Seguimentos , Produtos Finais de Glicação Avançada , Humanos , Estudos Longitudinais , Masculino , Microvasos/patologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Albumina Sérica Glicada
9.
Oncology ; 88(6): 337-44, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25721153

RESUMO

OBJECTIVE: Inflammation is associated with worse outcomes in cancer. Operations induce an acute inflammatory response and could impact the clinical outcomes in breast cancer. The neutrophil-lymphocyte ratio (NLR) is a well-known indicator of inflammation. We investigated the prognostic significance of perioperative inflammation with the NLR in breast cancer. METHODS: We reviewed the clinical and pathological records of women diagnosed with invasive breast carcinoma at the Samsung Medical Center between 2000 and 2010. The NLR levels in the immediate preoperative period and the postoperative periods (1 week and 1 month) were assessed. RESULTS: The NLRs of a total of 3,116 breast cancer patients were examined. In the univariate analysis, the NLR in postoperative week 1, total mastectomy, the presence of lymphovascular invasion, a higher nuclear grade and pathologic TNM stage, and negative hormone receptor and subtypes were factors associated with poor disease-specific survival. The NLR in postoperative week 1 remained a significant prognostic factor in the multivariate analysis. A cutoff level of 5.2, determined by the minimum p value approach, was found to be a significant level for discriminating the impact on breast cancer-specific mortality (p = 0.0116 adjusted by the Bonferroni correction). CONCLUSIONS: Immediate postoperative inflammation is an important prognostic marker in breast cancer patients.


Assuntos
Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Linfócitos/metabolismo , Neutrófilos/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/imunologia , Feminino , Humanos , Pessoa de Meia-Idade , Análise Multivariada , Invasividade Neoplásica , Período Pós-Operatório , Prognóstico , Estudos Retrospectivos , Adulto Jovem
10.
BMC Cancer ; 15: 138, 2015 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-25880075

RESUMO

BACKGROUND: Response to endocrine therapy in breast cancer correlates with estrogen receptor (ER) and progesterone receptor (PR) status. Generally, hormone receptor-positive (HR+) breast cancers have favorable prognosis. In order to understand the exact clinical characteristics and prognosis of single HR-positive breast cancer (ER + PR- tumors and ER-PR+ tumors), we compared these tumors to double HR+ tumors as well as HR- negative tumors (ER-PR-). METHODS: We examined the clinical and biological features of 6,980 women with invasive ductal carcinoma, and these patients were stratified according to ER and PR expression as double HR+ (ER + PR+), single HR+ (ER + PR- and ER-PR+) and double HR-negative (HR-, ER-PR-) tumors. RESULTS: In this study, 571 (8.2%) cases were single HR+ tumors, of which 90 (1.3%) were ER-PR+ tumors and 481 (6.9%) were ER + PR- tumors. Our multivariate analysis showed that in patients without HER2 overexpression ER + PR- tumors were associated with an increased risk of recurrence and death compared with ER + PR+ tumors, with a hazard ratio of 2.12 for disease-free survival (DFS) and 4.79 for overall survival (OS). In patients without HER2 overexpression ER-PR+ tumors had increased risk of recurrence and death compared with ER + PR+ tumor, with a hazard ratio of 4.19 for DFS and 7.22 for OS. In contrast, in patients with HER2 overexpression, the difference in survival between single HR+ tumors and double HR+ HR- tumors was not statistically significant. In patients without HER2 overexpression the DFS and OS of ER + PR- and ER-PR+ tumors were not significantly different from those of ER-PR- tumors. CONCLUSION: We have identified clinically and biologically distinct features of single HR+ tumors (ER-PR+ and ER + PR-) through comparison with both ER + PR+ and ER-PR- tumors. These differences were only significant in HER2- tumors, not in HER2+ tumors. Single HR+ tumors without HER2 overexpression (ER + PR-HER2- or ER-PR + HER2-) were associated with poorer survival than ER + PR + HER2- tumors, and had comparable poor survival to ER-PR-HER2- tumors (triple-negative breast cancer).


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/mortalidade , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Feminino , Seguimentos , Expressão Gênica , Humanos , Pessoa de Meia-Idade , Gradação de Tumores , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Prognóstico , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/genética , Receptores de Progesterona/genética , Fatores de Risco , Análise de Sobrevida , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/mortalidade , Adulto Jovem
11.
J Nanosci Nanotechnol ; 15(8): 5566-70, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26369118

RESUMO

Block copolymer composed of carboxymethyl dextran (CMDex) and methoxy poly(ethylene glycol) (MPEG) (abbreviated as CMDexPEG) was synthesized and doxorubicin (DOX) was conjugated with carboxyl groups of CMDexPEG. DOX-conjugated CMDexPEG block copolymer formed nanoparticles in water with sizes less than 100 nm. DOX-conjugated nanoparticles enhanced DOX delivery to the DOX-resistant CT26 cells and showed higher anticancer activity in vitro. DOX-conjugated nanoparticles inhibited growth of CT26 solid tumor at tumor-bearing mouse model study. In near infrared (NIR)-dye study, nanoparticles were retained in the tumor tissues for a longer period.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Dextranos/química , Doxorrubicina/administração & dosagem , Nanocápsulas/química , Nanoconjugados/química , Polietilenoglicóis/química , Animais , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Neoplasias Colorretais/patologia , Difusão , Relação Dose-Resposta a Droga , Doxorrubicina/química , Teste de Materiais , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanocápsulas/administração & dosagem , Nanocápsulas/ultraestrutura , Nanoconjugados/administração & dosagem , Nanoconjugados/ultraestrutura , Tamanho da Partícula , Propriedades de Superfície , Resultado do Tratamento
12.
J Nanosci Nanotechnol ; 15(2): 1130-4, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26353622

RESUMO

Caffeic acid-conjugated chitosan (ChitoCFA) and carboxymethyl dextran-b-poly(ethylene gycol) (CMD-PEG) copolymer were synthesized to fabricate self-organized nanoparticles. Nanoparticles were formed through ion-complex formation between ChitoCFA and CMD-PEG. Nanoparticles have small sizes ranged about 80 nm~300 nm with spherical shapes. Doxorubicin (DOX) was incorporated into the nanoparticles of ChitoCFA/CMD complexes. Particle sizes were increased according to the contents of drug. At drug release experiment, DOX was continuously released over 96 h. Anticancer acticity of nanoparticles were assessed with DOX-resistant CT26 cells. CT26 cells treated with DOX-incorporated nanoparticles revealed strong fluorescence intensity while free DOX revealed weak fluorescence intensity, indicating that DOX-loaded nanoparticles of ChitoCFA/CMD are promising vehicle for anticancer drug targeting.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Quitosana/química , Nanocápsulas/administração & dosagem , Nanocápsulas/química , Nanoconjugados/química , Neoplasias Experimentais/tratamento farmacológico , Antioxidantes/administração & dosagem , Ácidos Cafeicos/administração & dosagem , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Difusão , Doxorrubicina/administração & dosagem , Humanos , Nanocápsulas/ultraestrutura , Nanoconjugados/ultraestrutura , Neoplasias Experimentais/patologia , Tamanho da Partícula , Polietilenoglicóis , Resultado do Tratamento
13.
Cell Mol Life Sci ; 70(20): 3959-71, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23689589

RESUMO

Snail belongs to the superfamily of zinc-finger transcription factors and plays a crucial role in processes regulating cell fate, such as the formation of mesoderm and initiation of epithelial-mesenchymal transition. We have previously discovered that Snail modulates adiponectin expression in 3T3-L1 cells during adipogenesis. In the present study, we elucidated the functional role of Snail in adipocyte differentiation and its underlying molecular mechanism. Snail expression was dramatically decreased during adipogenesis in 3T3-L1 cells. Overexpression of Snail blocked adipocyte differentiation by suppressing the expression of peroxisome proliferator-activated receptor gamma (PPARγ) and CCAAT-enhancer-binding protein alpha, while knockdown of Snail expression stimulated adipogenesis in 3T3-L1 cells. Chromatin immunoprecipitation assay and luciferase assay showed that Snail inhibits the transcriptional activity of the PPARγ gene by directly binding to the E-box motifs in the PPARγ promoter. Wnt10b induced phosphorylation of glycogen synthase kinase 3 beta (GSK3ß), leading to inhibition of adipogenesis in 3T3-L1 cells in accordance with increased expression of Snail, whereas adipogenic capacity was restored in Snail siRNA-transfected preadipocytes. LiCl (a GSK3ß inhibitor)-treated cells also showed increased expression of Snail, with a reduced adipogenic potential. Snail-overexpressing 3T3-F442A cells did not differentiate into mature adipocytes in immunodeficient nude mice. Taken together, Snail is a novel regulator of adipocyte differentiation, which acts by direct suppression of PPARγ expression. Our data also indicate that the expression of Snail is mediated by the Wnt-GSK3ß signaling pathway.


Assuntos
Adipócitos/citologia , Adipogenia , PPAR gama/metabolismo , Fatores de Transcrição/metabolismo , Células 3T3-L1 , Adipócitos/metabolismo , Animais , Regulação da Expressão Gênica , Quinase 3 da Glicogênio Sintase/genética , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Masculino , Camundongos , Camundongos Nus , Mutagênese Sítio-Dirigida , Motivos de Nucleotídeos , PPAR gama/genética , Regiões Promotoras Genéticas , Fatores de Transcrição da Família Snail , Fatores de Transcrição/genética , Proteínas Wnt/genética , Proteínas Wnt/metabolismo , Via de Sinalização Wnt , beta Catenina/genética , beta Catenina/metabolismo
14.
Mol Cell Proteomics ; 11(1): M111.010884, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22023808

RESUMO

Cisplatin is used widely for treatment of a variety of cancer diseases. Recently, however, the use of cisplatin is restricted because of its adverse effects such as hepatotoxicity. There is no study with current proteomics technology to evaluate cisplatin-induced hepatotoxicity, even if some studies have reported on the hepatotoxicity. In this study, proteomic as well as genomic analyses have been used for identification of proteins and genes that respond to cisplatin treatment in rat primary hepatocytes. To investigate the hepatotoxic effects of cisplatin, rat primary hepatocytes were treated with an IC(20) concentration for 24 h. From proteomic analysis based on label-free quantitation strategy, cisplatin induced 76 up-regulated and 19 down-regulated proteins among 325 distinct proteins. In the mRNA level, genomic analysis revealed 72 up-regulated and 385 down-regulated genes in the cisplatin-treated group. Based on these two analyses, 19 pathways were commonly altered, whereas seven pathways were identified only by proteomic analysis, and 19 pathways were identified only by genomic analysis. Overall, this study explained the mechanism of cisplatin-induced hepatotoxicity with two points of view: well known pathways including drug metabolism, fatty acid metabolism, and glycolysis/TCA cycle and little known pathways including urea cycle and inflammation metabolism, for hepatotoxicity of other toxic agents. Up-regulated proteins detected by proteomic analysis in the cisplatin-treated group: FBP1 (fructose 1,6-bisphosphatase 1), FASN (fatty acid synthase), CAT (catalase), PRDX1 (peroxiredoxin-1), HSPD1 (60-kDa heat shock protein), MDH2 (malate dehydrogenase 2), and ARG1 (arginase 1), and also down-regulated proteins in the cisplatin-treated group: TPM1 (tropomyosin 1), TPM3 (tropomyosin 3), and CTSB (cathepsin B), were confirmed by Western blot analysis. In addition, up-regulated mRNAs detected by microarray analysis in the cisplatin-treated group: GSTA2, GSTT2, YC2, TXNRD1, CYP2E1, CYP2C13, CYP2D1, ALDH17, ARG1, ARG2, and IL-6, and also down-regulated mRNAs: CYP2C12, CYP26B1, TPM1, and TPM3, were confirmed by RT-PCR analysis. In case of PRDX1, FASN, and ARG1, they were further confirmed by immunofluorescence analysis. Through the integrated proteomic and genomic approaches, the present study provides the first pathway map related to cisplatin-induced hepatotoxicity, which may provide new insight into the mechanism of hepatotoxicity.


Assuntos
Antineoplásicos/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Cisplatino/toxicidade , Hepatócitos/efeitos dos fármacos , Animais , Células Cultivadas , Perfilação da Expressão Gênica , Hepatócitos/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Proteômica , RNA Mensageiro/metabolismo , Ratos
15.
Phytother Res ; 28(11): 1654-60, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24890258

RESUMO

Inflammation is a key regulatory process in cancer development. Prolonged exposure of breast tumor cells to inflammatory cytokines leads to epithelial-mesenchymal transition, which is the principal mechanism involved in metastasis and tumor invasion. Interleukin (IL)-1ß is a major inflammatory cytokine in a variety of tumors. To date, the regulatory mechanism of IL-1ß-induced cell migration and invasion has not been fully elucidated. Here, we investigated the effect of zerumbone (ZER) on IL-1ß-induced cell migration and invasion in breast cancer cells. The levels of IL-8 and matrix metalloproteinase (MMP)-3 mRNA were analyzed by real-time polymerase chain reaction. The levels of secreted IL-8 and MMP-3 protein were analyzed by enzyme-linked immunosorbent assay and western blot analysis, respectively. Cell invasion and migration was detected by Boyden chamber assay. The levels of IL-8 and MMP-3 expression were significantly increased by IL-1ß treatment in Hs578T and MDA-MB231 cells. On the other hand, IL-1ß-induced IL-8 and MMP-3 expression was decreased by ZER. Finally, IL-1ß-induced cell migration and invasion were decreased by ZER in Hs578T and MDA-MB231 cells. ZER suppresses IL-1ß-induced cell migration and invasion by inhibiting IL-8 expression and MMP-3 expression in TNBC cells. ZER could be a promising therapeutic drug for treatment of triple-negative breast cancer patients.


Assuntos
Interleucina-1beta/farmacologia , Interleucina-8/metabolismo , Metaloproteinase 3 da Matriz/metabolismo , Sesquiterpenos/farmacologia , Neoplasias de Mama Triplo Negativas/patologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Invasividade Neoplásica , Neoplasias de Mama Triplo Negativas/metabolismo
16.
J Hazard Mater ; 472: 134382, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38703675

RESUMO

The photocatalytic efficiency for removing volatile organic compounds (VOCs) is significantly influenced by operational parameters like humidity and flow velocity, exhibiting notable and inconsistent fluctuations in both lab-scale and large-scale demonstrations. In this study, operando spectroscopy and isotope analysis were employed to investigate the correlation between humidity levels and degradation of gaseous acetaldehyde using TiO2 photocatalysts, aiming to demonstrate the scaling-up of photocatalytic air purifier. It was observed that rate constants for the mineralization of acetaldehyde rapidly decreased by 30% as relative humidity increased from 25% to 80% in the flow system (with an air velocity, v = 0.78 m/s). However, batch system showed smaller change with only a 10% reduction of the rate constant. Humidity fluctuations were more pronounced under high-speed conditions and were amplified in air purifier (v = 3.8 m/s). Time-resolved operando spectroscopy using an 13C isotope of acetaldehyde revealed that humidity's distinct role in dark adsorption and photocatalytic reactions. Water was found to inhibit the formation of crotonaldehyde during aldol condensation reaction in dark condition. Moreover, water suppressed photocatalytic mineralization by inhibiting acetate oxidation to formate. These findings provide valuable insights for improving realistic air purification processes, underscoring the importance of identifying key intermediates and controlling humidity to enhance the selectivity of gaseous pollutant oxidation reactions.

17.
Proteomics ; 13(8): 1257-75, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23322611

RESUMO

Hepatocytes are used widely as a cell model for investigation of xenobiotic metabolism and the toxic mechanism of drugs. Simvastatin is the first statin drug used extensively in clinical practice for control of elevated cholesterol or hypercholesterolemia. However, it has also been reported to cause adverse effects in liver due to cellular damage. In this study, for proteomic and transcriptomic analysis, rat primary hepatocytes were exposed to simvastatin at IC20 concentration for 24 h. Among a total of 607 differentially expressed proteins, 61 upregulated and 29 downregulated proteins have been identified in the simvastatin-treated group. At the mRNA level, results of transcriptomic analysis revealed 206 upregulated and 41 downregulated genes in the simvastatin-treated group. Based on results of transcriptomic and proteomic analysis, NRF2-mediated oxidative stress response, xenobiotics by metabolism of cytochrome P450, fatty acid metabolism, bile metabolism, and urea cycle and inflammation metabolism pathways were focused using IPA software. Genes (FASN, UGT2B, ALDH1A1, CYP1A2, GSTA2, HAP90, IL-6, IL-1, FABP4, and ABC11) and proteins (FASN, CYP2D1, UG2TB, ALDH1A1, GSTA2, HSP90, FABP4, and ABCB11) related to several important pathways were confirmed by real-time PCR andWestern blot analysis, respectively. This study will provide new insight into the potential toxic pathways induced by simvastatin.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Redes e Vias Metabólicas/efeitos dos fármacos , Proteínas/metabolismo , Sinvastatina/efeitos adversos , Animais , Bile/metabolismo , Western Blotting , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Cromatografia Líquida/métodos , Sistema Enzimático do Citocromo P-450/metabolismo , Ácidos Graxos/metabolismo , Perfilação da Expressão Gênica , Hepatite/metabolismo , Masculino , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética , Proteínas/genética , Proteômica/métodos , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Reprodutibilidade dos Testes , Sinvastatina/toxicidade , Software , Ureia/metabolismo
18.
J Synchrotron Radiat ; 20(Pt 2): 383-5, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23412497

RESUMO

This study analyses the potential for laboratory-based size-exclusion chromatography (SEC) integrated small-angle X-ray scattering (SAXS) instrumentation to characterize protein complexes. Using a high-brilliance home source in conjunction with a hybrid pixel X-ray detector, the efficacy of SAXS data collection at pertinent protein concentrations and exposure times has been assessed. Scattering data from SOD1 and from the complex of SOD1 with its copper chaperone, using 10 min exposures, provided data quality in the range 0.03 < q < 0.25 Å(-1) that was sufficient to accurately assign radius of gyration, maximum dimension and molecular mass. These data demonstrate that a home source with integrated SEC-SAXS technology is feasible and would enable structural biologists studying systems containing transient protein complexes, or proteins prone to aggregation, to make advanced preparations in-house for more effective use of limited synchrotron beam time.


Assuntos
Cromatografia em Gel/instrumentação , Proteínas/química , Espalhamento a Baixo Ângulo , Difração de Raios X/instrumentação , Humanos , Chaperonas Moleculares/química , Conformação Proteica , Estrutura Quaternária de Proteína , Superóxido Dismutase/química , Superóxido Dismutase-1 , Difração de Raios X/métodos , Raios X
19.
Ann Surg Oncol ; 20(4): 1250-7, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23076556

RESUMO

BACKGROUND: Bariatric surgery effectively induces weight loss and resolves cardiovascular comorbidities in obese patients. We investigated cardiovascular and all-cause mortality in patients who underwent gastrectomies for early gastric cancer (EGC) and analyzed the changes in metabolic parameters after surgery. METHODS: A total of 2,477 patients who underwent gastrectomies for EGC between 1995 and 2004 were enrolled in the study and followed for mortality through 2007. Standardized mortality ratios (SMRs) were calculated using sex- and age-matched mortality in the general Korean population in 2005. Effects of gastrectomy on changes in body weight and metabolic parameters were investigated in 51 of the patients before and after surgery. RESULTS: During the 15,096.4 person-years of follow-up, 244 deaths were recorded. The all-cause mortality was not significantly different from that of the general population (SMR [95 % confidence interval (CI)] = 1.01 [0.89 - 1.14]); however, cardiovascular mortality was significantly lower (SMR = 0.35 [0.22 - 0.53]). In the 51 patients included in the second part of the study, significant reductions in body weight and visceral fat areas occurred after surgery, regardless of whether the patients were previously obese. Triglycerides, LDL-cholesterol, and plasminogen activator inhibitor-1 levels were significantly decreased, whereas HDL-cholesterol and adiponectin levels were increased. Carotid intima-media thickness also was significantly decreased in previously obese and nonobese patients. CONCLUSIONS: Patients with EGC who undergo gastrectomy have a lower cardiovascular mortality but similar all-cause mortality as that of the general population. In these patients, a significant reduction in body weight and visceral fat after surgery may improve impaired lipid metabolism and prevent atherosclerotic changes.


Assuntos
Doenças Cardiovasculares/mortalidade , Espessura Intima-Media Carotídea/mortalidade , Gastrectomia/mortalidade , Metabolismo dos Lipídeos , Complicações Pós-Operatórias , Neoplasias Gástricas/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/etiologia , Estudos de Coortes , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Fatores de Risco , Neoplasias Gástricas/complicações , Neoplasias Gástricas/cirurgia , Taxa de Sobrevida , Adulto Jovem
20.
Endocr J ; 60(11): 1231-40, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23965360

RESUMO

The proteins found in cow milk have been reported to cause systemic inflammation. Endoplasmic reticulum (ER) stress is known to be involved in the development of several metabolic disorders including insulin resistance and non-alcoholic fatty liver disease. However, the effect of thiazolidinediones (TZDs) on ER stress is still controversial. This is why we want to investigate in this study whether casein, which is the major protein in cow's milk, induces ER stress in the liver and whether rosiglitazone can attenuate these changes. Nine-week-old male Sprague-Dawley (SD) rats were separated into three groups: (1) vehicle treated; (2) daily subcutaneous injections of 1 mL 10% casein; (3) daily subcutaneous injection of 1 mL 10% casein and rosiglitazone 4 mg/[kg d]. After 6 weeks, body weight, food intake, glucose and lipid parameters, and serum AST/ALT levels were measured after an overnight fast. Real time RT-PCR and immunohistochemical staining for various ER stress markers were performed, and a TUNEL analysis was also performed. After 6 weeks, casein injection induced weight reduction, systemic inflammation, and hepatic dysfunction in SD rats. Casein injection increased both the gene and protein expression of ER stress markers in the liver and also caused hepatocyte apoptosis. Rosiglitazone treatment attenuated casein-induced systemic inflammation, ER stress, deteriorated liver function, and increased apoptosis. In conclusion, our results may provide further insight into the effects of casein on chronic inflammatory diseases, and to have a better understanding of the mechanism of the anti-inflammatory properties of rosiglitazone regardless of its hypoglycemic effect.


Assuntos
Anti-Inflamatórios/farmacologia , Modelos Animais de Doenças , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Tiazolidinedionas/farmacologia , Animais , Apoptose/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Caseínas , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Fígado/efeitos dos fármacos , Masculino , Ratos , Ratos Sprague-Dawley , Rosiglitazona
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