Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 127
Filtrar
Mais filtros

Bases de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Neoplasma ; 67(4): 909-915, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32386482

RESUMO

Hepatocellular carcinoma (HCC) is the third deadliest cancer in the world with high morbidity and poor prognosis. CTCFL (CCCTC-binding factor like) is a member of the cancer testis antigen (CTA) family with oncogenic properties. To demonstrate whether the hypomethylation of CTCFL promoters in plasma could be used as a noninvasive biomarker to predict poor prognosis of HCC, we extracted cell-free DNA from the plasma and detected the methylation status of CTCFL in 43 HCC, 5 liver cirrhosis and 6 benign lesion samples using methylation specific PCR (MSP). Our study indicated that the hypomethylation of CTCFL promoters in HCC plasma samples (60.4%) was significantly different from that in benign lesion plasma samples (16.7%) with a p-value of 0.043. Analysis of clinicopathological data showed that the methylation status of CTCFL promoters was significantly correlated with microvascular involvement (MVI) (p=0.001) and postoperative recurrence (p=0.031). Furthermore, clinical prognosis data of 347 HCC patients from The Cancer Genome Atlas (TCGA) database displayed that the hypomethylated group had worse overall survival than the hypermethylated group (p=0.0056). In conclusion, we provide evidence that the hypomethylation of CTCFL promoters in cell-free DNA is a biomarker for monitoring HCC patients, which can be used as a noninvasive prediction index for tumor recurrence and provide the individualized decision-making for clinicians.


Assuntos
Carcinoma Hepatocelular , Proteínas de Ligação a DNA , Neoplasias Hepáticas , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/genética , Ácidos Nucleicos Livres/análise , Metilação de DNA , Proteínas de Ligação a DNA/metabolismo , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/genética , Recidiva Local de Neoplasia/genética , Prognóstico , Regiões Promotoras Genéticas
2.
Photochem Photobiol Sci ; 18(10): 2442-2448, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31384873

RESUMO

In recent years, several drugs have become relatively easy to obtain with the rapid development of the economy and improvement in people's living standards. However, pathogenic bacteria have evolved strains that are resistant to certain drugs, such as antibiotics. Peptides are generally considered to be safe, have high tolerance to drugs, and are easy to manufacture. However, peptides are easily decomposed in complex biological environments. To solve this problem, many studies have modified peptides on the surface of nanomaterials to increase their functionality, biocompatibility, and stability. Meanwhile, nanomaterials have exhibited good absorption of near-infrared (NIR) light. When the NIR laser is focused on nanomaterials, photons are absorbed and the energy of the photons is converted into heat. Low-toxicity NRC03 peptide-conjugated dopamine/nano-reduced-graphene oxide (NRC03-DA/nRGO) nanomaterials are synthesized in this study for antibacterial testing using photothermal technology. The strains used in this study were Gram-positive Staphylococcus aureus (S. aureus). Our results indicated that the synthesized NRC03-DA/nRGO exhibits good absorption of NIR light and high photothermal conversion efficiency. Moreover, the synthesized NRC03-DA/nRGO inhibits the growth and survival of S. aureus. When the NRC03 peptide is modified on the surface of DA/nRGO, its biological stability is improved and the photothermal effect generated by NIR light produces additive effects, thereby indicating potential antibacterial applications.


Assuntos
Antibacterianos/farmacologia , Dopamina/química , Grafite/química , Nanoestruturas/química , Peptídeos/química , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/química , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Raios Infravermelhos
3.
Neoplasma ; 63(2): 288-98, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26674131

RESUMO

CD90 has been identified as a candidate marker of cancer stem cells (CSCs) for HCC, whereas it also has been considered as a marker for tumor-associated fibroblasts (CAFs). OCT4, as a key transcription factor required to maintain pluripotency of human embryonic stem cell and cancer cells, has been characterized to be involved in malignant transformation and tumorigenesis of various cancers. This study aimed to examine expression patterns of CD90 in HCC and investigate whether combination of both CD90 and OCT4 could provide a more powerful predictor for prognosis of HCC than either one alone.CD90 and OCT4 were examined by immunohistochemistry. The relationship between CD90/OCT4 expression and clinicopathologic characteristics was analyzed. The correlation between CD90/OCT4 expression and overall survival and disease-free survival was determined with Kaplan-Meier analysis.CD90 was found mainly expressed in tumor-associated CAFs and OCT4 was mainly expressed in tumor cells. The expression of CD90 and OCT4 in HCC was significantly higher than in adjacent non-tumor and normal liver tissues. CD90 expression was correlated with pathological grade, satellite lesion, PVTT and recurrence. OCT4 expression was correlated with pathological grade, tumor size and recurrence. Data demonstrated no correlation between CD90 and OCT4. High expression of CD90 or OCT4 predicts a poor prognosis. Furthermore, combination of both CD90 and OCT4 provides a more sensitive predictor for prognosis of HCC than either marker alone.CD90 and OCT4 are both independent and reliable biomarker for predicting prognosis of HCC patients after hepatic resection. Our results indicated the accuracy of prediction can be enhanced by their combination.


Assuntos
Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Fator 3 de Transcrição de Octâmero/metabolismo , Antígenos Thy-1/metabolismo , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/cirurgia , Linhagem Celular Tumoral , Transformação Celular Neoplásica/patologia , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Hepatectomia , Humanos , Fígado/patologia , Fígado/cirurgia , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Células-Tronco Neoplásicas/patologia
4.
Nature ; 452(7185): 332-5, 2008 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-18354478

RESUMO

Equal amounts of matter and antimatter are predicted to have been produced in the Big Bang, but our observable Universe is clearly matter-dominated. One of the prerequisites for understanding this elimination of antimatter is the nonconservation of charge-parity (CP) symmetry. So far, two types of CP violation have been observed in the neutral K meson (K(0)) and B meson (B(0)) systems: CP violation involving the mixing between K(0) and its antiparticle (and likewise for B(0) and ), and direct CP violation in the decay of each meson. The observed effects for both types of CP violation are substantially larger for the B(0) meson system. However, they are still consistent with the standard model of particle physics, which has a unique source of CP violation that is known to be too small to account for the matter-dominated Universe. Here we report that the direct CP violation in charged B(+/-)-->K(+/-)pi(0) decay is different from that in the neutral B(0) counterpart. The direct CP-violating decay rate asymmetry, (that is, the difference between the number of observed B(-)-->K(-)pi(0) event versus B(+)-->K(+) pi(0) events, normalized to the sum of these events) is measured to be about +7%, with an uncertainty that is reduced by a factor of 1.7 from a previous measurement. However, the asymmetry for versus B(0)-->K(+)pi(-) is at the -10% level. Although it is susceptible to strong interaction effects that need further clarification, this large deviation in direct CP violation between charged and neutral B meson decays could be an indication of new sources of CP violation-which would help to explain the dominance of matter in the Universe.

5.
Water Sci Technol ; 69(11): 2357-63, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24901632

RESUMO

In this study, the biodegradability of nanoscale zero-valent iron (nZVI) dispersants and their effects on the intrinsic biodegradation of trichloroethylene (TCE) were evaluated. Results of a microcosm study show that the biodegradability of three dispersants followed the sequence of: polyvinyl alcohol-co-vinyl acetate-co-itaconic acid (PV3A) > polyoxyethylene (20) sorbitan monolaurate (Tween 20) > polyacrylic acid (PAA) under aerobic conditions, and PV3A > Tween 20 > PAA under anaerobic conditions. Natural biodegradation of TCE was observed under both aerobic and anaerobic conditions. No significant effects were observed on the intrinsic biodegradation of TCE under aerobic conditions with the presence of the dispersants. The addition of PAA seemed to have a slightly adverse impact on anaerobic TCE biodegradation. Higher accumulation of the byproducts of anaerobic TCE biodegradation was detected with the addition of PV3A and Tween 20. The diversity of the microbial community was enhanced under aerobic conditions with the presence of more biodegradable PV3A and Tween 20. The results of this study indicate that it is necessary to select an appropriate dispersant for nZVI to prevent a residual of the dispersant in the subsurface. Additionally, the effects of the dispersant on TCE biodegradation and the accumulation of TCE biodegrading byproducts should also be considered.


Assuntos
Biodegradação Ambiental , Ferro/química , Nanopartículas Metálicas/química , Tricloroetileno/química , Tricloroetileno/metabolismo , Poluentes Químicos da Água/química , Poluentes Químicos da Água/metabolismo
6.
Phys Rev Lett ; 108(3): 031801, 2012 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-22400727

RESUMO

We report measurements of the branching fractions and CP asymmetries for B(±)→ηh(±) (h=K or π) and the observation of the decay B(0)→ηK(0) from the final data sample of 772×10(6) B ̅B pairs collected with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. The measured branching fractions are B(B(±)→ηK(±))=(2.12±0.23±0.11)×10(-6), B(B(±)→ηπ(±))=(4.07±0.26±0.21)×10(-6), and B(B(0)→ηK(0))=(1.27(-0.29)(+0.33)±0.08)×10(-6), where the last decay is observed for the first time with a significance of 5.4 standard deviations (σ). We also find evidence for CP violation in the charged B modes, A(CP)(B(±)→ηK(±))=-0.38±0.11±0.01 and A(CP)(B(±)→ηπ(±))=-0.19±0.06±0.01 with significances of 3.8 σ and 3.0 σ, respectively. For all measurements, the first and second uncertainties are statistical and systematic, respectively.


Assuntos
Partículas Elementares , Método de Monte Carlo , Incerteza
7.
HIV Med ; 12(6): 343-51, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21059166

RESUMO

BACKGROUND: The emergency department (ED) is one of the most frequent sources of medical care for many HIV-infected individuals. However, the characteristics and ED utilization patterns of patients with HIV/AIDS-related illness as the primary ED diagnosis (HRIPD) are unknown. METHODS: We identified the ED utilization patterns of HRIPD visits from a weighted sample of US ED visits (1993-2005) using the National Hospital Ambulatory Medical Care Survey, a nationally representative survey. Data on visits by patients≥18 years old were analysed using procedures for multiple-stage survey data. We compared the utilization patterns of HRIPD vs. non-HRIPD visits, and patterns across three periods (1993-1996, 1997-2000 and 2001-2005) to take into account changes in HIV epidemiology. RESULTS: Overall, 492 000 HRIPD visits were estimated to have occurred from 1993 to 2005, corresponding to 5-in-10 000 ED visits. HRIPD visits experienced longer durations of stay (5.2 h vs. 3.4 h; P=0.001), received more diagnostic tests (5.1 vs. 3.3; P<0.001), were prescribed more medications (2.5 vs. 1.8; P<0.001) and were more frequently seen by physicians (99.5%vs. 93.8%; P<0.001) compared with non-HRIPD visits. HRIPD visits were more likely to result in admission [adjusted odds ratio (OR) 7.67; 95% confidence interval (CI) 5.14-11.44]. The proportion of HRIPD visits that required emergent/urgent care or were seen by attending physicians, and the number of diagnostic tests ordered, significantly increased over time (P<0.05), while the wait time (P=0.003) significantly decreased between the second and third study periods (P<0.05). CONCLUSIONS: Although HRIPD visits were infrequent relative to all ED visits, HRIPD visits utilized significantly more resources than non-HRIPD visits and the utilization also increased over time.


Assuntos
Serviço Hospitalar de Emergência/estatística & dados numéricos , Infecções por HIV/terapia , Ferimentos e Lesões/epidemiologia , Adolescente , Adulto , Feminino , Infecções por HIV/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Índice de Gravidade de Doença , Estados Unidos/epidemiologia , Adulto Jovem
8.
Phys Rev Lett ; 105(19): 191803, 2010 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-21231162

RESUMO

We report a first measurement of inclusive B→Xsη decays, where Xs is a charmless state with unit strangeness. The measurement is based on a pseudoinclusive reconstruction technique and uses a sample of 657×10(6)BB pairs accumulated with the Belle detector at the KEKB e+e- collider. For MXs < 2.6 GeV/c2, we measure a branching fraction of [26.1±3.0(stat)-2.1+1.9(syst)-7.1+4.0(model)]×10(-5) and a direct CP asymmetry of ACP=-0.13±0.04-0.03+0.02. Over half of the signal occurs in the range MXs > 1.8 GeV/c2.

9.
Phys Rev Lett ; 104(23): 231801, 2010 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-20867227

RESUMO

First observations of the B(s)(0) → D(s)(*-) π+, B(s)(0) → D(s)(-) ρ+ and B(s)(0) → D(s)(*-) ρ+ decays are reported together with measurements of their branching fractions: B(B(s)(0) → D(s)(*-) π+) = [2.4(-0.4)(+0.5)(stat) ± 0.3(syst) ± 0.4(f(s))]×10(-3), B(B(s)(0) → D(s)(-) ρ+) = [8.5(-1.2)(+1.3)(stat) ± 1.1(syst) ± 1.3(f(s))]×10(-3) and B(B(s)(0) → D(s)(*-) ρ+) = [11.9(-2.0)(+2.2)(stat) ± 1.7(syst) ± 1.8(f(s))]×10(-3) (f(s) = N(B(s)(*) B(s)(*))/N(bb)). From helicity-angle distributions, we measured the longitudinal polarization fraction in B(s)(0) → D(s)(*-) ρ+ decays to be f(L)(B(s)(0) → D(s)(*-) ρ+) = 1.05(-0.10)(+0.08)(stat)(-0.04)(+0.03)(syst). These results are based on a 23.6 fb(-1) data sample collected at the Υ(5S) resonance with the Belle detector at the KEKB e+ e- collider.


Assuntos
Partículas Elementares , Teoria Quântica
10.
J Int Med Res ; 38(1): 1-8, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20233508

RESUMO

Studies investigating the association between interleukin-10 -819 promoter polymorphism and gastric cancer risk report conflicting results. This study aimed to summarize quantitatively the evidence for such a relationship. Two investigators independently searched the Medline (January 1966-January 2009) and Embase (January 1980-January 2009) databases for eligible studies to be included in a meta-analysis. Six case-control studies, which included 681 gastric cancer cases and 1621 control subjects were selected. Combined results for all studies showed that there was no significant difference in genotype distribution (TT, TC or CC) between gastric cancer patients and control subjects. When stratifying for race, results were similar except that Asian patients with gastric cancer had a significantly lower frequency of TT and a higher frequency of TC than Asian control subjects. When stratifying by location and Lauren's classification of gastric cancer, there was no significant difference in genotype distribution between patients with gastric cancer and control subjects. This meta-analysis suggests that the interleukin-10 -819 promoter polymorphism may be associated with gastric cancer in Asians.


Assuntos
Povo Asiático/genética , Interleucina-10/genética , Polimorfismo Genético/genética , Regiões Promotoras Genéticas/genética , Neoplasias Gástricas/genética , Estudos de Casos e Controles , Predisposição Genética para Doença , Genótipo , Humanos , Fatores de Risco , Neoplasias Gástricas/patologia
11.
J Dent Res ; 99(8): 907-913, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32374712

RESUMO

Silver diamine fluoride (SDF) is used topically to prevent or arrest dental caries and has been tested clinically in toddlers to elderly adults. Following SDF application, small quantities of silver can be swallowed and absorbed. To monitor silver concentrations, pharmacokinetic studies can be performed. However, pharmacokinetic studies are time-consuming, resource intensive, and challenging to perform in young children. The objective of this study was to develop a physiologically based pharmacokinetic (PBPK) model to predict silver disposition in children. The PBPK model for silver was developed using Simcyp software (version 17.0) based on information obtained from literature sources. The predictive performance of the model was assessed by comparing the predicted PK profiles and parameters with the observed data from published rat and human data following intravenous or oral silver administration. The predicted silver concentrations were within 2-fold of observed blood and tissue silver concentrations in rats and within the 95% confidence interval of observed plasma silver concentrations in healthy human adults. The PBPK model was applied to the pediatric population by accounting for developmental physiological changes. For a given SDF dose, the simulated peak silver concentrations were 5.2-, 4.3-, 2.7-, and 1.3-fold higher in children aged 1 to 2, 2 to 4, 5 to 10, and 12 to 17 y, respectively, compared to adults. As silver is reportedly excreted in the bile, the half-life of silver was comparable in all ages and plasma and tissue silver concentrations were predicted to return to baseline levels within 2 wk after SDF application. The simulation in children suggests that conventional SDF application to teeth to prevent or arrest dental caries results in plasma and tissue silver concentrations lower than toxic concentrations. PBPK modeling offers a novel approach to studying dental exposures in younger children, where pharmacokinetic studies would be difficult to conduct.


Assuntos
Compostos de Amônio Quaternário/farmacologia , Compostos de Prata/farmacologia , Animais , Cariostáticos , Cárie Dentária , Fluoretos Tópicos/farmacologia , Humanos , Ratos
12.
Phys Rev Lett ; 103(17): 171801, 2009 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-19905747

RESUMO

We study B --> K(*)l+l- decays (l = e, mu) based on a data sample of 657 x 10(6) BB pairs collected with the Belle detector at the KEKB e+e- collider. We report the differential branching fraction, isospin asymmetry, K* polarization, and the forward-backward asymmetry (A(FB)) as functions of q2 = M(ll)(2)c2. The fitted A(FB) spectrum exceeds the standard model expectation by 2.7 standard deviations. The measured branching fractions are B(B --> K*l+l-) = (10.7(-1.0)(+1.1) +/- 0.9) x 10(-7) and B(B --> Kl+l-) = (4.8(-0.4)(+0.5) +/- 0.3) x 10(-7), where the first errors are statistical and the second are systematic, with the muon to electron ratios R(K*) = 0.83 +/- 0.17 +/- 0.08 and R(K) = 1.03 +/- 0.19 +/- 0.06.

13.
Water Environ Res ; 81(7): 687-94, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19691249

RESUMO

The objective of this study was to evaluate the feasibility of using ferrous ion-activated persulfate oxidation to remediate groundwater contaminated with methyl tert-butyl ether (MTBE). In this study, batch experiments were conducted to evaluate the effects of various factors on the efficiency of MTBE degradation including persulfate concentrations, ferrous ion concentrations, and persulfate coupled with hydrogen peroxide. Results show that ferrous ion-activated persulfate oxidation was capable of degrading MTBE efficiently. Persulfate and ferrous ion concentrations correlated with MTBE degradation rates. However, excess addition of ferrous ion resulted in decreased MTBE degrading rates most likely because of competition for sulfate free radicals between ferrous ion and MTBE. Two main byproducts of MTBE degradation, tert-butyl formate and tert-butyl alcohol, were detected in the experiments; both were, however, subsequently degraded. Results of sulfate analysis show that proper addition of ferrous ion could prevent unnecessary persulfate decomposition.


Assuntos
Poluentes Atmosféricos/química , Compostos Ferrosos/química , Éteres Metílicos/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Formiatos/química , Íons , Cinética , Oxirredução , terc-Butil Álcool/química
14.
Oncogene ; 36(41): 5768-5769, 2017 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-28714962

RESUMO

This corrects the article DOI: 10.1038/onc.2014.445.

15.
Oncogene ; 35(37): 4891-902, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-26876205

RESUMO

The SET protein is a potent inhibitor of protein phosphatase 2A (PP2A). Here, we report the oncogenic role of SET in hepatocarcinogenesis, clinical aggressiveness and anti-hepatocellular carcinoma (HCC) therapeutics. By analyzing samples obtained from 147 HCC patients, we found that SET overexpression was detected specifically in 30.6% HCC tumor samples, and was significantly associated with worse clinical features and high p-Akt expression in HCC tumors. Co-expression of SET and Akt predicted shorter post-operative recurrence-free survival in this cohort (P=0.045). Furthermore, SET was significantly associated with cell growth and hepatosphere formation. To elucidate the anti-HCC potential of targeting SET, we generated a novel SET antagonist, EMQA (N(4)-(3-ethynylphenyl)-6,7-dimethoxy-N(2)-(4-phenoxyphenyl) quinazoline-2,4-diamine). EMQA enhanced PP2A activity via disrupting SET-PP2Ac (catalytic domain of PP2A) binding in HCC cells, which restored PP2A-mediated p-Akt downregulation and promoted HCC cell death. In HCC cells or recombinant proteins expressing the N- and C- truncated forms of SET, only the C-terminal SET was required for EMQA targeting. Furthermore, combining sorafenib and EMQA showed good synergism in inhibiting HCC survival. Our findings suggested the oncogenic role of SET and the adverse prognostic value of SET overexpression in HCC. This alteration defines a subgroup of HCC patients who could benefit from SET antagonists, such as EMQA.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Chaperonas de Histonas/genética , Neoplasias Hepáticas/tratamento farmacológico , Prognóstico , Quinazolinas/administração & dosagem , Fatores de Transcrição/genética , Animais , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proteínas de Ligação a DNA , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Chaperonas de Histonas/antagonistas & inibidores , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Niacinamida/administração & dosagem , Niacinamida/análogos & derivados , Compostos de Fenilureia/administração & dosagem , Quinazolinas/síntese química , Sorafenibe , Fatores de Transcrição/antagonistas & inibidores , Ensaios Antitumorais Modelo de Xenoenxerto
16.
J Hazard Mater ; 125(1-3): 10-6, 2005 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-16046063

RESUMO

Methyl tert-butyl ether (MTBE) has been used as a gasoline additive to improve the combustion efficiency and to replace lead since 1978. Because it is widely used and it has been disposed inappropriately, MTBE has become a prevalent groundwater contaminant worldwide. In this study, two petroleum-hydrocarbon contaminated sites (Sites A and B) were selected to evaluate the occurrence and effectiveness of natural attenuation of MTBE at these two sites. Field investigation results indicate that the natural attenuation mechanisms of MTBE at both sites were occurring with the first-order attenuation rates of 0.0021 and 0.0048 1day(-1) at Sites A and B, respectively. Results also reveal that the intrinsic biodegradation pattern was the most important mechanism among the natural attenuation processes at both sites. Results from BIOSCREEN simulation suggest that biodegradation was responsible for 78 and 59% of MTBE mass reduction at Sites A and B, respectively. Investigation results show that MTBE plume at Site B could be effectively controlled via natural attenuation processes. However, MTBE plume at Site A has migrated to a farther downgradient area and passed the boundary line of the site. Thus, more active groundwater remedial technologies should be applied at Site A to protect the downgradient environment. Results from this study suggest that natural attenuation might be feasible to be used as a remedial option for the remediation of MTBE-contaminated site on the premise that (1) detailed site characterization has been conducted and (2) the occurrence and effectiveness of natural attenuation processes have been confirmed.


Assuntos
Poluentes Ambientais , Poluição Ambiental/prevenção & controle , Hidrocarbonetos/química , Éteres Metílicos/química , Petróleo , Biodegradação Ambiental , Modelos Químicos , Concentração Osmolar , Taiwan
17.
Oncogene ; 34(41): 5252-63, 2015 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-25619838

RESUMO

Epithelial-to-mesenchymal transition (EMT) is well known to involve in tumor invasion and metastasis. Src homology region 2 domain-containing phosphatase 1 (SHP-1) functions as a potent tumor suppressor and also acts as a negative regulator of p-STAT3(Tyr705) oncogenic signaling. However, little is known about the molecular mechanism(s) through which SHP-1 regulates EMT during hepatocellular carcinoma (HCC) progression. Here we first reported that endogenous SHP-1 protein levels were significantly downregulated in cells with mesenchymal characteristics and negatively correlated with p-STAT3(Tyr705) and vimentin but positively correlated with E-cadherin. SHP-1 overexpression abolished transforming growth factor-ß1 (TGF-ß1)-induced p-STAT3(Tyr705) and EMT, as well inhibited migration and invasion but further rescued by signal transducer and activator of transcription factor 3 (STAT3) overexpression. Depletion of SHP-1 could induce a more increase in TGF-ß1-induced p-STAT3(Tyr-705) and EMT characteristics, further supporting the mechanism that suppression of TGF-ß1-induced EMT is dependent on SHP-1-mediated STAT3 inactivation. Constitutively overexpressed SHP-1 tyrosine phosphatase activity by D61A-mutated SHP-1 markedly reduced TGF-ß1-induced p-STAT3(Tyr705) and EMT features but was not altered by C453S catalytic-dead mutant SHP-1. Consequently, SHP-1 acted as a powerful suppressor in preventing EMT by exerting its tyrosine phosphatase activity that directly downregulated p-STAT3(Tyr705). Most notably, we discovered a novel SHP-1 agonist SC-43 better than sorafenib to exert more potent anti-EMT effects in vitro as well as anti-metastatic growth in vivo. In conclusion, SHP-1 is a potent suppressor of HCC EMT and metastasis, thus highlighting that SC-43-SHP-1 axis may serve as a potential therapeutic target that antagonized p-STAT3(Tyr705) and thereby prevented HCC EMT and metastasis.


Assuntos
Carcinoma Hepatocelular/enzimologia , Transição Epitelial-Mesenquimal , Neoplasias Hepáticas/enzimologia , Neoplasias Pulmonares/enzimologia , Proteína Tirosina Fosfatase não Receptora Tipo 6/fisiologia , Animais , Carcinoma Hepatocelular/secundário , Linhagem Celular Tumoral , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Pulmonares/secundário , Camundongos Nus , Transplante de Neoplasias , Fator de Transcrição STAT3/metabolismo
18.
Arch Ophthalmol ; 94(12): 2086-91, 1976 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-999554

RESUMO

The Catford apparatus for determining the objective visual acuity was elevated with 20 normal (20 eyes) and 40 abnormal (75 diseased eyes) patients. The vision of the normal individuals was fogged with neutral-density filters and convex lenses. Eyes with normal or near normal vision showed good correlation between optokinetic response and visual acuity, but no correlation was observed in eyes with poor vision. These findings, which vary from those of Catford, indicate that objective methods of visual acuity testing using a nystagmoid response do not appear useful for general clinical purposes.


Assuntos
Testes Visuais/métodos , Acuidade Visual , Estudos de Avaliação como Assunto , Humanos , Testes Visuais/instrumentação
19.
Water Res ; 38(3): 663-72, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14723935

RESUMO

Pentachlorophenol (PCP) has been used in the past as a pesticide, herbicide, antifungal agent, bactericide, and wood preservative. Thus, PCP is among the most ubiquitous chlorinated compounds found in groundwater contamination. A former pesticide manufacturing plant located in southern Taiwan has been identified as a PCP spill site. In this study, groundwater samples collected from the PCP site were analyzed to assess the occurrence of natural PCP biodegradation. Microcosm experiments were conducted to (1) evaluate the feasibility of biodegrading PCP by indigenous microbial consortia under aerobic and cometabolic conditions, and (2) determine the potential of enhancing PCP biodegradation using cane molasses and biological sludge cake as the substitute primary substrates under cometabolic conditions. The inocula used in this microcosm study were aquifer sediments collected from the PCP site and activated sludges collected from the municipal and industrial wastewater treatment plants. Results from this field investigation indicate that the natural biodegradation of PCP is occurring and causing the decrease in PCP concentration. Microcosm results show that the indigenous microorganisms can biodegrade PCP under both aerobic and aerobic cometabolism conditions. A PCP-degrading bacterium was isolated from the collected aquifer sediments and identified as Pseudomonas mendocina NSYSU via some biochemical tests and further conformation of DNA sequencing. In batch cultures, P. mendocina NSYSU used PCP as its sole source of carbon and energy. The isolated bacterium, P. mendocina NSYSU, was capable of completely degrading PCP as indicated by the increase in biomass formation with the decrease in PCP concentrations occurred in the carbon-free medium simultaneously. Results indicate that the in situ or on-site aerobic bioremediation using indigenous microorganisms or inoculated bacteria would be a feasible technology to clean up the studied PCP-contaminated site. Results from this study will be useful in designing a scale-up in situ or on-site PCP bioremediation system (e.g., on-site bioreactor) for field application.


Assuntos
Indústria Química , Pentaclorofenol/metabolismo , Praguicidas/metabolismo , Pseudomonas mendocina/fisiologia , Poluentes do Solo/metabolismo , Poluentes Químicos da Água/metabolismo , Acidentes , Biodegradação Ambiental , Resíduos Perigosos , Abastecimento de Água
20.
Yi Chuan Xue Bao ; 27(10): 853-7, 2000.
Artigo em Zh | MEDLINE | ID: mdl-11192427

RESUMO

Litter size is one of the most important economic traits in pig production, and the more piglet numbers per litter is capable to increase pork production and bring more economic profit for pig industry. ESR (estrogen receptor) gene has been determined to be one of the major genes affecting phenotype of litter size without any genetic negative correlation to growth and carcass traits. An optimized standard PCR-RFLP protocol is employed to type 262 sows from 5 different breeds in ESR loci, and then with the computation based on linear model ESR gene is confirmed to be a major locus significantly associated with litter size (P < 0.001). The genetic effect of ESR gene is quite large in these breeds, especially in these Chinese pig population. The sows of beneficial homozygote BB produce 1.40-3.37 total number born/litter and 0.63-3.58 number born alive/litter more than the sows of non-beneficial homozygote AA do. The information found in the present study is very important and could be utilized as DNA marker for improvement of reproduction trait in practice of pig breeding.


Assuntos
Tamanho da Ninhada de Vivíparos , Receptores de Estrogênio/genética , Suínos/genética , Animais , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA