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1.
Indoor Air ; 2018 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-29855107

RESUMO

This study determines the relative survival (RS) of Bacillus subtilis spores loaded on an N95 filtering facepiece respirator (FFR) after decontamination by five methods under worst-case conditions. Relative survival was obtained by testing after decontamination and after storing the FFRs at 37°C and 95% relative humidity for 24 hours. The decontamination methods involved ethanol, bleach, ultraviolet irradiation (UVA 365 nm, UVC 254 nm), an autoclave, and a traditional electric rice cooker (TERC) that was made in Taiwan. Without decontamination, 59 ± 8% of the loaded spores survived for 24 hours. When 70% ethanol was added to the N95 FFR at a packing density of 0.23, the RS was 73 ± 5% initially and decayed to 22 ± 8% in 24 hours. Relative survival remained above 20% after 20 minutes of UVA irradiation. The other four decontamination measures achieved 99%-100% biocidal efficacy, as measured immediately after the methods were applied to the test FFRs. Relative survival is a useful parameter for measuring sterilization or degree of disinfection. Bleach, UVC, an autoclave, and a TERC provide better biocidal efficacy than ethanol and UVA. Not only a higher filter quality but also a lower value of RS produced the most decontaminated FFR.

2.
Pharmacogenomics J ; 16(6): 536-539, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-26503813

RESUMO

A recent study identified a variant of the NUDT15 gene (rs116855232 C>T) associated with intolerance to thiopurine in Korean patients with Crohn's disease. This study prompted us to substantiate the finding in a Taiwanese population. Four hundred and four children with acute lymphoblastic leukemia (ALL), and 100 adults with chronic immune thrombocytopenic purpura or localized lymphoma having normal bone marrow were examined. Two candidate gene approaches, pyrosequencing for NUDT15 and TaqMan assay for thiopurine methyltransferase (TPMT) genotyping (rs1142345 A>G), were performed. We showed a risk allele frequency of NUDT15 of 11.6% in children with ALL and 15.5% in adults. By contrast, the risk allele frequency of TPMT was only 1.6% in children with ALL and 0.5% in adults. The high frequency of risk variant for NUDT15, but not the very low frequency of risk variant for TPMT, was closely associated with the intolerance to mercaptopurine in children with ALL in Taiwan, contrast to that of European descent. In regard to NUDT15 polymorphism, the maximal tolerable daily doses of mercaptopurine in homozygotes, heterozygotes and wild-type groups were 9.4 mg m-2, 30.7 mg m-2 and 44.1 mg m-2, respectively. The outcomes did not differ significantly among the different genotypes.


Assuntos
Antimetabólitos Antineoplásicos/efeitos adversos , Mercaptopurina/efeitos adversos , Variantes Farmacogenômicos , Polimorfismo Genético , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Pirofosfatases/genética , Fatores Etários , Antimetabólitos Antineoplásicos/administração & dosagem , Criança , Pré-Escolar , Intervalo Livre de Doença , Feminino , Frequência do Gene , Estudos de Associação Genética , Heterozigoto , Homozigoto , Humanos , Lactente , Recém-Nascido , Estimativa de Kaplan-Meier , Masculino , Dose Máxima Tolerável , Mercaptopurina/administração & dosagem , Farmacogenética , Testes Farmacogenômicos/métodos , Fenótipo , Reação em Cadeia da Polimerase , Medicina de Precisão , Leucemia-Linfoma Linfoblástico de Células Precursoras/enzimologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Valor Preditivo dos Testes , Pirofosfatases/metabolismo , Fatores de Risco , Taiwan , Fatores de Tempo , Resultado do Tratamento
3.
Diabet Med ; 31(7): e25-8, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24698085

RESUMO

BACKGROUND: Purulent pericarditis is an acute and fulminant disease characterized by pus accumulation in the pericardial space. Its incidence has declined substantially and the common pathogen has changed since the beginning of the antibiotic era; however, it is still found in some patients with immunocompromised conditions. CASE REPORT: We report a rare case in which the onset of diabetes mellitus presented as extremely high HbA1c concentration, ketoacidosis, multi-site abscesses and purulent pericarditis. After antibiotic therapy and pericardiocentesis, the purulent pericarditis still did not resolve and further intrapericardial thrombolytic therapy also failed. Finally, this patient was treated successfully by surgical debridement and pericardiectomy. CONCLUSION: In the immunocompromised state of severe hyperglycaemia, purulent pericarditis is a possible complication of uncontrolled infection. If purulent pericarditis cannot be cured using non-surgical treatments, such as antibiotic therapy, pericardiocentesis and intrapericardial thrombolytic therapy, a surgical pericardiectomy should be considered to avoid morbidity and mortality.


Assuntos
Abscesso/diagnóstico , Abscesso/terapia , Antibacterianos/uso terapêutico , Desbridamento , Diabetes Mellitus Tipo 2/complicações , Cetose/etiologia , Pericardiectomia , Pericardite/diagnóstico , Pericardite/terapia , Abscesso/patologia , Diabetes Mellitus Tipo 2/diagnóstico , Ecocardiografia , Fibrinolíticos/uso terapêutico , Humanos , Cetose/terapia , Masculino , Pessoa de Meia-Idade , Pericardiocentese , Supuração , Terapia Trombolítica , Resultado do Tratamento
4.
BJOG ; 119(5): 614-25, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22313859

RESUMO

OBJECTIVE: To evaluate the clinical value of prenatal array comparative genomic hybridisation (CGH) in screening for submicroscopic genomic imbalances. DESIGN: Cross-sectional study. SETTING: Tertiary referral centre. POPULATION: From June 2008 to February 2011, 3171 fetuses underwent prenatal array CGH testing and karyotyping at the National Taiwan University Hospital. Indications for invasive prenatal diagnosis included abnormal karyotype, abnormal ultrasound, advanced maternal age and parental anxiety. METHODS: In all, 2497 fetuses were screened with 1-Mb resolution bacterial artificial chromosome array-based CGH, and 674 fetuses with 60-K oligonucleotide array-based CGH. Multiplex ligation-dependent probe amplification, fluorescence in situ hybridization, or 105-K oligonucleotide array CGH provided further confirmation. MAIN OUTCOME MEASURE: Copy number variations identified by array CGH. RESULTS: Array CGH detected numerical chromosome anomalies in 37 (1.2%) fetuses, microdeletion/duplication in 34 (1.1%) fetuses, large deletion/duplication in 13 (0.4%) fetuses, benign copy number changes in 13 (0.4%) fetuses and variation of unknown clinical significance in five (0.2%) fetuses. Array CGH was effective in identifying submicroscopic genomic imbalance in fetuses with de novo balance translocations (2/17, 1.8%), supernumerary marker chromosomes (3/6, 50%), and abnormal prenatal ultrasound findings (33/194, 17.0%). Array CGH detected microdeletions/duplications in 12 fetuses with normal karyotype. CONCLUSION: Prenatal array CGH is effective in screening for submicroscopic genomic imbalance. Array CGH may add 8.2% to the diagnostic field, compared with conventional karyotyping, for fetuses with abnormal ultrasound results, and is particularly useful in fetuses with karyotypic balanced translocation or marker chromosomes. There is a 0.52% baseline risk of submicroscopic genomic imbalance, even in women with an uneventful prenatal examination.


Assuntos
Aberrações Cromossômicas , Hibridização Genômica Comparativa/métodos , Diagnóstico Pré-Natal/métodos , Adulto , Ansiedade/etiologia , Estudos Transversais , Feminino , Humanos , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Pais/psicologia , Gravidez , Diagnóstico Pré-Natal/psicologia , Adulto Jovem
5.
J Nanosci Nanotechnol ; 11(3): 2752-5, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21449469

RESUMO

Effect of dopants on the soft magnetic properties and high frequency characteristics of FeCoBM thin films (M = Ti, Nb, Hf, and Ta) have been studied. For (Fe0.55Co0.45)(100-x)B(x) (x = 5-15) thin films, with the increase of B content, the resistivity was increased because B could decrease the crystallinity of the films. The (Fe0.55Co0.45)90B10 thin film showed the optimum properties, where 4piM(s) = 16.1 kG, H(ce) = 64.2 Oe, H(ch) = 13.5 Oe, H(k) = 310 Oe and p = 338 microomega-cm. To reduce the coercivity of the film, the elements M, including Ti, Nb, Hf, and Ta, were selected to substitute for B in the FeCoB films. It was found that (Fe0.55Co0.45)90B6Ti2Nb2 thin film after annealing at a temperature of 200 degrees C for 30 min showed the optimal properties, where 4piM(s) = 15.8 kG, H(ce) = 4.8 Oe, H(ch) = 3.6 Oe, H(k) = 224 Oe and p = 290 microomega-cm. The theoretically calculated ferromagnetic resonance frequency of the developed films can be higher than 5 GHz.


Assuntos
Cobalto/química , Cristalização/métodos , Ferro/química , Magnetismo , Membranas Artificiais , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Dureza , Teste de Materiais , Tamanho da Partícula
6.
Pharmacogenomics J ; 10(6): 537-44, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20066004

RESUMO

Because angiotensin-converting enzyme (ACE) activity is implicated widely in biological systems, we aimed to identify its novel quantitative trait loci for the purposes of understanding ACE activity regulation and pharmacogenetics relating to ACE inhibitor (ACEI). We performed a two-stage genome-wide association study: (1) from 400 young-onset hypertension (YOH) subjects and (2) a confirmation study with an additional 623 YOH subjects. In the first stage, eight single nucleotide polymorphisms (SNPs) of the ACE structural gene and one SNP of ABO genes were significantly associated with ACE activity. SNP rs4343 in exon17 near the well-known insertion/deletion polymorphism had the strongest association. We confirmed in the second stage that three SNPs: rs4343 in ACE gene (P=3.0 x 10⁻²5), rs495828 (P=3.5 x 10⁻8) and rs8176746 (P=9.3 x 10⁻5) in ABO gene were significantly associated with ACE activity. We further replicated the association between ABO genotype/blood types and ACE activity in an independent YOH family study (428 hypertension pedigrees), and showed a potential differential blood pressure response to ACEI in subjects with varied numbers of ACE-activity-raising alleles. These findings may broaden our understanding of the mechanisms controlling ACE activity and advance our pharmacogenetic knowledge on ACEI.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Peptidil Dipeptidase A/genética , Locos de Características Quantitativas , Sistema ABO de Grupos Sanguíneos/genética , Adulto , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Pressão Sanguínea/genética , Feminino , Estudo de Associação Genômica Ampla , Humanos , Hipertensão/tratamento farmacológico , Hipertensão/genética , Masculino , Peptidil Dipeptidase A/sangue , Polimorfismo de Nucleotídeo Único
7.
Clin Exp Rheumatol ; 28(3): 318-24, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20576226

RESUMO

OBJECTIVES: The genetic control of Interleukin-10 (IL-10) and Tumour necrosis factor-alpha (TNF-alpha) production and the possible interaction between the two cytokines in influencing SLE susceptibility as well as clinical features has not been completely evaluated in the Taiwanese population. METHODS: We investigated the association of IL-10 and TNF-alpha promoter polymorphisms (-1082, -819 and -592 for IL-10 gene; -308 for TNF-alpha gene) with SLE in a total of 172 Taiwanese patients and 215 controls. RESULTS: Our results indicate that IL-10 A/T/A-A/T/A genotype was associated with Taiwanese SLE, whereas no significance was observed between TNF-alpha genotype and SLE. Furthermore, the TNF-alpha G allele frequency of the polymorphism at -308 was significantly decreased in patients with oral ulcers. The combined frequencies of IL-10 A/T/A haplotype and TNF-alpha G-G genotype were significantly increased in SLE patients. In addition, the combined frequencies of IL-10 A/T/A haplotype and TNF-alpha G-G genotype were significantly decreased in patients with oral ulcers. CONCLUSIONS: These results suggest a significant correlation of the combined IL-10 and TNF-alpha genetic polymorphisms contribute to SLE susceptibility and clinical features in the Taiwanese population.


Assuntos
Interleucina-10/genética , Lúpus Eritematoso Sistêmico/epidemiologia , Lúpus Eritematoso Sistêmico/genética , Polimorfismo de Nucleotídeo Único , Fator de Necrose Tumoral alfa/genética , Frequência do Gene , Predisposição Genética para Doença/epidemiologia , Haplótipos , Humanos , Úlceras Orais/epidemiologia , Úlceras Orais/genética , Fenótipo , Regiões Promotoras Genéticas/genética , Fatores de Risco , Taiwan/epidemiologia
8.
J Cell Biol ; 126(6): 1585-93, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8089188

RESUMO

Integrin-mediated cell adhesion, or cross-linking of integrins using antibodies, often results in the enhanced tyrosine phosphorylation of certain intracellular proteins, suggesting that integrins may play a role in signal transduction processes. In fibroblasts, platelets, and carcinoma cells, a novel tyrosine kinase termed pp125FAK has been implicated in integrin-mediated tyrosine phosphorylation. In some cell types, integrin ligation or cell adhesion has also been shown to result in the increased expression of certain genes. Although it seems reasonable to hypothesize that integrin-mediated tyrosine phosphorylation and integrin-mediated gene induction are related, until now, there has been no direct evidence supporting this hypothesis. In the current report, we explore the relationship between integrin-mediated tyrosine phosphorylation and gene induction in human monocytes. We demonstrate that monocyte adherence to tissue culture dishes or to extracellular matrix proteins is followed by a rapid and profound increase in tyrosine phosphorylation, with the predominant phosphorylated component being a protein of 76 kD (pp76). Tyrosine phosphorylation of pp76 and other monocyte proteins can also be triggered by incubation of monocytes with antibodies to the integrin beta 1 subunit, or by F(ab')2 fragments of such antibodies, but not by F(ab) fragments. The ligation of beta 1 integrins with antibodies or F(ab')2 fragments also induces the expression of immediate-early (IE) genes such as IL-1 beta. When adhering monocytes are treated with the tyrosine kinase inhibitors genistein or herbimycin, both phosphorylation of pp76 and induction of IL-1 beta message are blocked in a dose-dependent fashion. Similarly, treatment with genistein or herbimycin can block tyrosine phosphorylation of pp76 and IL-1 beta message induction mediated by ligation of beta 1 integrin with antibodies. These observations suggest that protein tyrosine phosphorylation is an important aspect of integrin-mediated IE gene induction in monocytes. The cytoplasmic tyrosine kinase pp125FAK, although important in integrin signaling in other cell types, seems not to play a role in monocytes because this protein could not be detected in these cells.


Assuntos
Regulação da Expressão Gênica/fisiologia , Genes Precoces , Integrinas/fisiologia , Monócitos/fisiologia , Fosfoproteínas/biossíntese , Tirosina/metabolismo , Benzoquinonas , Adesão Celular/fisiologia , Moléculas de Adesão Celular/metabolismo , Células Cultivadas , Quinase 1 de Adesão Focal , Proteína-Tirosina Quinases de Adesão Focal , Genisteína , Humanos , Interleucina-1/biossíntese , Isoflavonas/farmacologia , Lactamas Macrocíclicas , Monócitos/metabolismo , Fosforilação , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/metabolismo , Quinonas/farmacologia , Rifabutina/análogos & derivados , Ativação Transcricional
9.
J Cell Biol ; 136(6): 1385-95, 1997 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-9087451

RESUMO

Integrin-mediated cell adhesion causes activation of MAP kinases and increased tyrosine phosphorylation of focal adhesion kinase (FAK). Autophosphorylation of FAK leads to the binding of SH2-domain proteins including Src-family kinases and the Grb2-Sos complex. Since Grb2-Sos is a key regulator of the Ras signal transduction pathway, one plausible hypothesis has been that integrin-mediated tyrosine phosphorylation of FAK leads to activation of the Ras cascade and ultimately to mitogen activated protein (MAP) kinase activation. Thus, in this scenario FAK would serve as an upstream regulator of MAP kinase activity. However, in this report we present several lines of evidence showing that integrin-mediated MAP kinase activity in fibroblasts is independent of FAK. First, a beta1 integrin subunit deletion mutant affecting the putative FAK binding site supports activation of MAP kinase in adhering fibroblasts but not tyrosine phosphorylation of FAK. Second, fibroblast adhesion to bacterially expressed fragments of fibronectin demonstrates that robust activation of MAP kinase can precede tyrosine phosphorylation of FAK. Finally, we have used FRNK, the noncatalytic COOH-terminal domain of FAK, as a dominant negative inhibitor of FAK autophosphorylation and of tyrosine phosphorylation of focal contacts. Using retroviral infection, we demonstrate that levels of FRNK expression sufficient to completely block FAK tyrosine phosphorylation were without effect on integrin-mediated activation of MAP kinase. These results strongly suggest that integrin-mediated activation of MAP kinase is independent of FAK and indicate the probable existence of at least two distinct integrin signaling pathways in fibroblasts.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Moléculas de Adesão Celular/fisiologia , Fibroblastos/fisiologia , Integrina beta1/fisiologia , Proteínas Tirosina Quinases/fisiologia , Transdução de Sinais/fisiologia , Células 3T3 , Animais , Adesão Celular , Galinhas , Ativação Enzimática/efeitos dos fármacos , Fibroblastos/enzimologia , Quinase 1 de Adesão Focal , Proteína-Tirosina Quinases de Adesão Focal , Proteína Adaptadora GRB2 , Integrina beta1/genética , Camundongos , Fragmentos de Peptídeos/metabolismo , Mutação Puntual , Proteínas/fisiologia , Proteínas Recombinantes de Fusão/metabolismo , Transfecção
10.
Lupus ; 18(11): 974-9, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19762398

RESUMO

Tumour necrosis factor-alpha (TNF-alpha), an important proinflammatory cytokine, exerts a variety of physiological and pathogenic effects that lead to tissue destruction. Studies on the association of TNF-alpha genetic polymorphisms with systemic lupus erythematosus (SLE) have yielded inconclusive results. We investigated the association of TNF-alpha genetic polymorphisms (-1031T/C, -863C/A, -857T/C, -308A/G and +489A/G) with SLE in Taiwanese patients and controls. Our results indicate that 1) the frequency of the A-allele at -863 position was significantly higher in SLE patients (odds ratio = 1.46; 95% CI = 1.02-2.08); 2) the frequency of the A-allele at +489 position was significantly higher in SLE patients (odds ratio = 1.79; 95% CI = 1.21-2.65); 3) the AA or GA genotype frequencies at +489 position were significantly increased in SLE patients (AA genotype: odds ratio = 11.20; 95% CI = 1.36-92.55; GA genotype: odds ratio = 1.63; 95% CI = 1.03-2.58); 4) no significant association of TNF-alpha haplotypic distributions was observed, except for the haplotypes TCCGA, CACGA and CCCGG; and 5) the genotype frequency of the polymorphisms at -1031 was significantly different in patients with antinuclear antibodies (P = 0.022). The allele and genotype frequencies of the polymorphisms at -863 were not significantly different. The genotype frequency of the polymorphisms at -857 was significantly different in patients with haematological disorder (P = 0.025). The frequency of A allele of the polymorphisms at -308 was significantly increased in patients with malar rash (P = 0.033), discoid rash (P = 0.023), photosensitivity (P = 0.037), oral ulcers (P = 0.002) and serositis (P = 0.029). The genotype frequency of the polymorphisms at +489 was significantly different in patients with discoid rash and photosensitivity (data not shown; discoid rash, P = 0.031; photosensitivity, P = 0.044). These results suggest that TNF-alpha genetic polymorphisms contribute to SLE susceptibility in the Taiwanese population.


Assuntos
Povo Asiático/genética , Lúpus Eritematoso Sistêmico/genética , Lúpus Eritematoso Sistêmico/imunologia , Polimorfismo Genético , Fator de Necrose Tumoral alfa/genética , Alelos , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Haplótipos , Humanos , Lúpus Eritematoso Sistêmico/fisiopatologia , Taiwan
11.
Clin Nephrol ; 72(6): 457-67, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19954723

RESUMO

AIM: The angiotensin II Type 1 receptor (AT1R) A1166C (rs5186) genez polymorphism is equivocally associated with the patients' susceptibility to chronic kidney disease or end-stage renal disease. We conducted a prospective study to investigate the influence of AT1R A1166C gene polymorphism on the quantitative changes of renal function. METHOD: Of 1500 people screened, 112 non-diabetic normotensive elderly Chinese were recruited and received biochemistry examination at the baseline, at the second and fourth year follow-up. Serum creatinine and calculated renal parameters, using Cockroft-Gault (CG) formula, Modification of Diet in Renal Disease (MDRD) Study and abbreviated MDRD (abMDRD) equation, were used to evaluate renal function and their progression. Genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism. RESULT: Age was 71.9 +/- 3.7 years (range 60 - 81). Serum creatinine, CG creatinine clearance (CrCl), MDRD and abMDRD glomerular filtration rate (GFR) were significantly decreased at the 2 and 4-year follow-up (all p < 0.001). The magnitude of 4-year decline of above four renal parameters was significantly higher in subjects carrying the AT1R AA genotype than C-allele carriers (p = 0.014, 0.033, 0.008 and 0.014 for creatinine, CG CrCl, MDRD and abMDRD GFR, respectively). This association was still significant in multivariate analyses (p = 0.019, 0.045, 0.035 and 0.018, respectively). CONCLUSION: This longitudinal study showed that the aging process was associated with decline of renal function in the healthy elderly. The AT1R A1166C gene polymorphism might modulate these changes in the Chinese. This provides further knowledge essential in the assessment of renal disease and determination of renal function in the older subjects.


Assuntos
Envelhecimento/fisiologia , DNA/genética , Predisposição Genética para Doença , Falência Renal Crônica/genética , Polimorfismo Genético , Receptor Tipo 1 de Angiotensina/genética , Idoso , Idoso de 80 Anos ou mais , Alelos , Feminino , Seguimentos , Genótipo , Humanos , Falência Renal Crônica/sangue , Falência Renal Crônica/epidemiologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prevalência , Prognóstico , Receptor Tipo 1 de Angiotensina/sangue , Valores de Referência , Estudos Retrospectivos , Taiwan/epidemiologia , Fatores de Tempo
12.
J Phys Condens Matter ; 21(2): 026013, 2009 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-21814006

RESUMO

We investigated the magnetic and ferroelectric properties of c-axis oriented orthorhombic phase HoMnO(3) (o-HMO in Pbnm symmetry setting) thin films grown on Nb-doped SrTiO(3)(001) substrates. The o-HMO films exhibit an antiferromagnetic ordering near 42 K, irrespective of the orientation of the applied field. However, an additional magnetic ordering occurring around 35 K was observed when the field was applied along the c-axis of o-HMO, which was absent when the field was applied in the ab-plane. The magnetocapacitance measured along the c-axis showed that although there is evidence of dielectric constant enhancement when the temperature is below 35 K the expected abrupt change in dielectric constant appears at a much lower temperature and reaches maximum around 13.5 K, indicating that the low-temperature c-axis polarization might be related to the ordering of the Ho(3+) moment. The lattice constant analyses using x-ray diffraction and the observation of a slight magnetization hysteresis suggest that the weak second magnetic transition along the c-axis at 35 K might be more relevant to the strain-induced effect on antiferromagnetism.

13.
Biotech Histochem ; 94(5): 374-380, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30819007

RESUMO

KHC-4 is a 2-phenyl-4-quinolone analogue that exhibits anticancer activity. Aberrant activation of ß-catenin signaling contributes to prostate cancer development and progression. Therefore, targeting ß-catenin expression could be a useful approach to treating prostate cancer. We found that KHC-4 can inhibit ß-catenin expression and its signaling pathway in DU145 prostate cancer cells. Treatment with KHC-4 decreased total ß-catenin expression and concomitantly decreased ß-catenin levels in both the cytoplasm and nucleus of cells. KHC-4 treatment also inhibited ß-catenin expression and that of its target proteins, PI3K, AKT, GSK3ß and TBX3. We monitored the stability of ß-catenin with the proteasomal inhibitor, MG132, in DU145 cells and found that MG132 reversed KHC-4-induced proteasomal ß-catenin degradation. We verified CDK1/ß-catenin expression in KHC-4 treated DU145 cells. We found that roscovitine treatment reversed cell proliferation by arresting the cell cycle at the G2/M phase and ß-catenin expression caused by KHC-4 treatment. We suggest that KHC-4 inhibits ß-catenin signaling in DU145 prostate cancer cells.


Assuntos
Antineoplásicos/uso terapêutico , Morfolinas/uso terapêutico , Neoplasias da Próstata/metabolismo , Quinolonas/uso terapêutico , beta Catenina/biossíntese , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Masculino , Morfolinas/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Quinolonas/metabolismo , Roscovitina/metabolismo , Roscovitina/uso terapêutico , Transdução de Sinais/efeitos dos fármacos
14.
Int J Obes (Lond) ; 32(2): 268-74, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17878891

RESUMO

OBJECTIVE: Epicardial and abdominal adipose tissues have recently been demonstrated to play inflammatory roles in coronary atherosclerosis. We sought to compare tissue adipocytokine levels of these two anatomically distinct adipose stores in patients with and without coronary artery diseases (CAD). DESIGN: Samples of abdominal and epicardial fat tissues were harvested to detect the levels of adipocytokines and proinflammatory mediators. SUBJECTS: Forty-six patients with CAD who underwent coronary artery bypass surgery and 12 non-CAD control subjects who underwent other types of open-heart surgery. MEASUREMENTS: Tissue levels of adipocytokines (adiponectin, leptin and visfatin) and proinflammatory mediators (tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6)) were determined by enzyme-linked immunosorbent assay. RESULTS: Tissue levels of TNF-alpha, IL-6, leptin and visfatin were significantly higher in CAD patients relative to control subjects. In addition, significantly higher tissue levels of these four cytokines from abdominal fat depots were found compared to those from epicardial fat in CAD patients. Conversely, in comparison with control subjects, tissue levels of adiponectin were significantly reduced in CAD patients with a significantly lower tissue levels of abdominal than epicardial fat depots demonstrated. CONCLUSION: Abdominal adiposity may play more significant role than epicardial fat in the pathogenesis of coronary atherosclerosis.


Assuntos
Adipocinas/metabolismo , Tecido Adiposo/metabolismo , Doença da Artéria Coronariana/metabolismo , Mediadores da Inflamação/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Doença da Artéria Coronariana/etiologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Obesidade/metabolismo
15.
Biotechnol Bioeng ; 99(6): 1535-41, 2008 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-17972333

RESUMO

A problem nowadays tissue engineers encounter in developing sizable tissue implants is the nonuniform spread of cells and/or extracellular matrices. Research shows such a nutrients transport restriction may be improved by employing hydrodynamic culture systems. We propose a compact model for the simulation of cell growth in a porous construct under direct perfusion. Unlike the previous model proposed in the literature, which composes a cellular scaffold sandwiched between two culture media layers, the current model includes only the scaffold layer to simplify the mathematical and computational complex. Results show the present single-layer model can predict cell spreads and the nutrient and metabolic waste distribution as accurately as does the three-layer model. Only if the hydrodynamic aspects such as the pressure and viscous stress are prominent to know, should the more sophisticated analyses with the three-layer model be employed. The compact model provides comparable investigations for the tissue-engineering construct developments.


Assuntos
Técnicas de Cultura de Células/métodos , Células Cultivadas/fisiologia , Mecanotransdução Celular/fisiologia , Modelos Biológicos , Perfusão/métodos , Engenharia Tecidual/métodos , Animais , Proliferação de Células , Simulação por Computador , Humanos
16.
FEBS Lett ; 581(6): 1161-5, 2007 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-17328898

RESUMO

Aggregated beta-amyloid (Abeta) peptides are neurotoxic and cause neuronal death both in vitro and in vivo. Although the formation of a beta-sheet structure is usual required to form aggregates, the relationship between neurotoxicity and the Abeta sequence remains unclear. To explore the correlation between Abeta sequence, secondary structure, aggregative ability, and neurotoxicity, we utilized both full-length and fragment-truncated Abeta peptides. Using a combination of spectroscopic and cellular techniques, we demonstrated that neurotoxicity and aggregative ability are correlated while the relationship between these characteristics and secondary structure is not significant. The hydrophobic C-terminus, particularly the amino acids of 17-21, 25-35, and 41-42, is the main region responsible for neurotoxicity and aggregation. Deleting residues 17-21, 25-35 or 41-42 significantly reduced the toxicity. On the other hand, truncation of the peptides at either residues 22-24 or residues 36-40 had little effect on toxicity and aggregative ability. While the N-terminal residues 1-16 may not play a major role in neurotoxicity and aggregation, a lack of N-terminal fragment Abeta peptide, (e.g. Abeta17-35), does not display the neurotoxicity of either full-length or 17-21, 25-35 truncated Abeta peptides.


Assuntos
Peptídeos beta-Amiloides/química , Peptídeos beta-Amiloides/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Sequência de Aminoácidos , Animais , Dimerização , Humanos , Síndromes Neurotóxicas/etiologia , Células PC12 , Estrutura Secundária de Proteína , Ratos , Deleção de Sequência
17.
Leukemia ; 20(2): 218-23, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16341046

RESUMO

The fusion transcripts of MLL rearrangement [MLL(+)] in acute myeloid leukemia (AML) and their clinicohematologic correlation have not be well characterized in the previous studies. We used Southern blot analysis to screen MLL(+) in de novo AML. Reverse transcriptase-polymerase chain reaction was used to detect the common MLL fusion transcripts. cDNA panhandle PCR was used to identify infrequent or unknown MLL partner genes. MLL(+) was identified in 114 (98 adults) of 988 AML patients. MLL fusion transcripts comprised of 63 partial tandem duplication of MLL (MLL-PTD), 14 MLL-AF9, 9 MLL-AF10, 9 MLL-ELL, 8 MLL-AF6, 4 MLL-ENL and one each of MLL-AF1, MLL-AF4, MLL-MSF, MLL-LCX, MLL-LARG, MLL-SEPT6 and MLL-CBL. The frequency of MLL-PTD was 7.1% in adults and 0.9% in children (P<0.001). 11q23 abnormalities were detected in 64% of MLL/t11q23 and in none of MLL-PTD by conventional cytogenetics. There were no differences in remission rate, event-free survival and overall survival between adult MLL-PTD and MLL/t11q23 groups. Adult patients had a significantly poorer outcome than children. The present study showed that cDNA panhandle PCR can identify all rare or novel MLL partner genes. MLL-PTD was rare in childhood AML. MLL(+) adults had a poor outcome with no difference in survival between MLL-PTD and MLL/t11q23 groups.


Assuntos
Leucemia Mieloide/genética , Proteína de Leucina Linfoide-Mieloide/genética , Proteínas de Fusão Oncogênica/genética , Translocação Genética/genética , Doença Aguda , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Pré-Escolar , Feminino , Duplicação Gênica , Histona-Lisina N-Metiltransferase , Humanos , Lactente , Recém-Nascido , Leucemia Mieloide/diagnóstico , Leucemia Mieloide/terapia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Taxa de Sobrevida , Resultado do Tratamento
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