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1.
Int J Mol Sci ; 24(2)2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36675278

RESUMO

Epithelial-mesenchymal transition (EMT) has been implicated in cancer progression, invasion, and metastasis. We aimed to evaluate the correlations between clinicopathological characteristics and EMT markers in patients with hepatocellular carcinoma (HCC) who underwent surgical resection and to identify the key regulator in EMT process. Fresh-frozen HCC tissues and adjacent nontumor liver tissues from 30 patients who underwent surgical resection were provided by the Gachon University Gil Medical Center Bio Bank. Human HCC cell lines, Hep3B, SNU449, and Huh7 cells were transfected with Rac1 siRNA and exposed to hypoxic conditions. The combined EMT markers expression (down-expression of E-cadherin and overexpression of p21-activated kinases 1 (PAK1)/Snail) by Western blot in HCC tissues when compared to adjacent nontumor liver tissues was significantly associated with macrovascular invasion (p = 0.021), microvascular invasion (p = 0.001), large tumor size (p = 0.021), and advanced tumor stage (p = 0.015). Patients with combined EMT markers expression showed early recurrence and poor overall survival. In vitro studies showed that Rac1 knockdown decreased the expression of EMT markers including PAK1 and Snail in hypoxia-induced Hep3B cells and suppressed the migration and invasion of hypoxia-induced HCC cells. Rac1 may be a potential therapeutic target for inhibition of EMT process through the inhibition of PAK1 and Snail in HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Transição Epitelial-Mesenquimal/genética , Relevância Clínica , Transdução de Sinais , Hipóxia/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Regulação Neoplásica da Expressão Gênica , Proteínas rac1 de Ligação ao GTP/genética , Proteínas rac1 de Ligação ao GTP/metabolismo
2.
Eur Radiol ; 31(7): 4751-4763, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33389037

RESUMO

OBJECTIVE: To evaluate and compare the diagnostic performance of the updated HCC guidelines using gadoxetic acid-enhanced MRI. METHODS: In this study, patients at risk of HCC who underwent gadoxetic acid-enhanced MRI following US/CT surveillance were retrospectively recruited from 3 centers. Three radiologists independently evaluated hepatic nodule imaging features relevant to the diagnostic criteria outlined in each guideline. Per-lesion sensitivity, specificity, and accuracy were compared between guidelines using logistic regression with a generalized estimating equation. Inter-observer agreements on imaging features were determined using Fless κ statistics. RESULTS: Altogether, 447 nodules (310 HCCs, 20 combined hepatocellular-cholangiocarcinomas, 2 cholangiocarcinomas, and 115 benign entities) measuring 1-3 cm from 386 patients were assessed. The KLCA-NCC and APASL guidelines showed the highest sensitivity (82.3-90.6%, p < .001) and accuracy (83.9-88.6%) among the five guidelines. The OPTN/UNOS guideline showed the highest specificity (94.9-97.1%), followed by the AASLD/LI-RADS, EASL, KLCA-NCC, and APASL guidelines, with significant difference only with the APASL guideline. The diagnostic performance of the updated AASLD/LI-RADS and EASL guidelines and of the KLCA-NCC and APASL guidelines was comparable (p > .05). Inter-observer agreement was substantial to almost perfect (κ = 0.73-0.87). CONCLUSIONS: For the diagnosis of HCC using gadoxetic acid-enhanced MRI, the KLCA-NCC and APASL guidelines showed the highest sensitivity and accuracy. The OPTN/UNOS guideline showed the highest specificity. Acknowledging their relative strengths and weaknesses could help adapt the diagnostic criteria according to the clinical context. KEY POINTS: • APASL and KLCA-NCC provided significantly the highest sensitivity and accuracy, followed by AASLD/LI-RADS and EASL in an endemic area for hepatitis B. • OPTN/UNOS showed the highest specificity, followed by AASLD/LI-RADS, EASL, KLCA-NCC, and APASL guidelines, with significant difference only with APASL. • Broadened definition of arterial hyperenhancement, washout, and the size of the lesion eligible to apply diagnostic criteria may improve the diagnostic performance for HCC in an endemic area for hepatitis B.


Assuntos
Neoplasias dos Ductos Biliares , Carcinoma Hepatocelular , Neoplasias Hepáticas , Ductos Biliares Intra-Hepáticos , Carcinoma Hepatocelular/diagnóstico por imagem , Meios de Contraste , Gadolínio DTPA , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Imageamento por Ressonância Magnética , Estudos Retrospectivos , Sensibilidade e Especificidade
3.
Sensors (Basel) ; 21(16)2021 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-34451076

RESUMO

Panax ginseng has been used as a traditional medicine to strengthen human health for centuries. Over the last decade, significant agronomical progress has been made in the development of elite ginseng cultivars, increasing their production and quality. However, as one of the significant environmental factors, heat stress remains a challenge and poses a significant threat to ginseng plants' growth and sustainable production. This study was conducted to investigate the phenotype of ginseng leaves under heat stress using hyperspectral imaging (HSI). A visible/near-infrared (Vis/NIR) and short-wave infrared (SWIR) HSI system were used to acquire hyperspectral images for normal and heat stress-exposed plants, showing their susceptibility (Chunpoong) and resistibility (Sunmyoung and Sunil). The acquired hyperspectral images were analyzed using the partial least squares-discriminant analysis (PLS-DA) technique, combining the variable importance in projection and successive projection algorithm methods. The correlation of each group was verified using linear discriminant analysis. The developed models showed 12 bands over 79.2% accuracy in Vis/NIR and 18 bands with over 98.9% accuracy at SWIR in validation data. The constructed beta-coefficient allowed the observation of the key wavebands and peaks linked to the chlorophyll, nitrogen, fatty acid, sugar and protein content regions, which differentiated normal and stressed plants. This result shows that the HSI with the PLS-DA technique significantly differentiated between the heat-stressed susceptibility and resistibility of ginseng plants with high accuracy.


Assuntos
Panax , Análise Discriminante , Resposta ao Choque Térmico , Humanos , Análise dos Mínimos Quadrados , Espectroscopia de Luz Próxima ao Infravermelho
4.
Hepatology ; 70(2): 621-629, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30194739

RESUMO

Acute liver failure (ALF) caused by hepatitis A is a rare but fatal disease. Here, we developed a model to predict outcome in patients with ALF caused by hepatitis A. The derivation set consisted of 294 patients diagnosed with hepatitis A-related ALF (ALFA) from Korea, and a validation set of 56 patients from Japan, India, and United Kingdom. Using a multivariate proportional hazard model, a risk-prediction model (ALFA score) consisting of age, international normalized ratio, bilirubin, ammonia, creatinine, and hemoglobin levels acquired on the day of ALF diagnosis was developed. The ALFA score showed the highest discrimination in the prediction of liver transplant or death at 1 month (c-statistic, 0.87; 95% confidence interval [CI], 0.84-0.92) versus King's College criteria (KCC; c-statistic, 0.56; 95% CI, 0.53-0.59), U.S. Acute Liver Failure Study Group index specific for hepatitis A virus (HAV-ALFSG; c-statistic, 0.70; 95% CI, 0.65-0.76), the new ALFSG index (c-statistic, 0.79; 95% CI, 0.74-0.84), Model for End-Stage Liver Disease (MELD; c-statistic, 0.79; 95% CI, 0.74-0.84), and MELD including sodium (MELD-Na; c-statistic, 0.78; 95% CI, 0.73-0.84) in the derivation set (all P < 0.01). In the validation set, the performance of the ALFA score (c-statistic, 0.84; 95% CI, 0.74-0.94) was significantly better than that of KCC (c-statistic, 0.65; 95% CI, 0.52-0.79), MELD (c-statistic, 0.74; 95% CI, 0.61-0.87), and MELD-Na (c-statistic, 0.72; 95% CI, 0.58-0.85) (all P < 0.05), and better, but not statistically significant, than that of the HAV-ALFSG (c-statistic, 0.76; 95% CI, 0.61-0.90; P = 0.28) and new ALFSG indices (c-statistic, 0.79; 95% CI, 0.65-0.93; P = 0.41). The model was well-calibrated in both sets. Conclusion: Our disease-specific score provides refined prediction of outcome in patients with ALF caused by hepatitis A.


Assuntos
Hepatite A/complicações , Falência Hepática Aguda/etiologia , Falência Hepática Aguda/cirurgia , Transplante de Fígado/estatística & dados numéricos , Modelos Estatísticos , Adulto , Feminino , Humanos , Falência Hepática Aguda/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico , Medição de Risco , Fatores de Tempo
5.
J Gastroenterol Hepatol ; 35(6): 1078-1087, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31907970

RESUMO

BACKGROUND AND AIM: Exogenous 8-hydroxydeoxyguanosine (8-OHdG) was suggested as an inhibitor of Rac1 and NADPH oxidase (NOX). The aim of this study was to evaluate the effects of the exogenous 8-OHdG on hepatic fibrogenesis in vitro and in vivo model of liver fibrosis. METHODS: Adult Sprague-Dawley rats were allocated to sham-operated rats (n = 7), rats that underwent bile duct ligation (BDL) (n = 6), and BDL rats treated with 8-OHdG (60 mg/kg/day by gavage, n = 6). All rats were sacrificed on day 21. Double immunofluorescence staining between either NOX1 or NOX2 and α-smooth muscle actin (SMA) in liver was performed. Hepatic fibrotic contents were assessed by hydroxyproline assay and quantified by Sirius red staining. In vitro, hepatic stellate cell (HSC) line LX-2 and HHSteC cells were stimulated by angiotensin II (10 µM). The reactive oxygen species (ROS) production was measured by confocal microscopy. The expressions of NOX1, NOX2, α-SMA, transforming growth factor (TGF)-ß1, and collagen Iα were analyzed by quantitative real-time polymerase chain reaction or immunoblotting. RESULTS: The 8-OHdG treatment in BDL rats reduced the NOX1 and NOX2 protein expression, which overlapped with α-SMA compared with BDL rats. The 8-OHdG treatment in BDL rats significantly decreased the mRNA expression of NOX1, NOX2, α-SMA, TGF-ß1, and collagen Iα, and fibrotic contents. Increases of ROS production, Rac1 activation, NOX1, NOX2, and fibronectin expression induced by angiotensin II in HSCs were attenuated by 8-OHdG. CONCLUSIONS: Rac1 activation and NOX-derived ROS are implicated to liver fibrosis. The 8-OHdG ameliorates liver fibrosis through the inhibition of Rac1 activation and NOX-derived ROS.


Assuntos
8-Hidroxi-2'-Desoxiguanosina/farmacologia , 8-Hidroxi-2'-Desoxiguanosina/uso terapêutico , Actinas/genética , Actinas/metabolismo , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/genética , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/genética , NADPH Oxidase 1/metabolismo , NADPH Oxidase 2/genética , NADPH Oxidase 2/metabolismo , NADPH Oxidases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Proteínas rac1 de Ligação ao GTP/metabolismo , Animais , Linhagem Celular , Colágeno/genética , Colágeno/metabolismo , Modelos Animais de Doenças , Células Estreladas do Fígado , Cirrose Hepática/etiologia , Cirrose Hepática/metabolismo , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismo
6.
J Korean Med Sci ; 34(41): e264, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31650719

RESUMO

BACKGROUND: The long-term data with direct acting antiviral agents were rare. This study investigated the durability of a sustained virologic response (SVR) and the improvement of fibrosis after daclatasvir and asunaprevir (DCV/ASV) treatment in genotype 1b (GT1b) hepatitis C virus (HCV)-infected patients. METHODS: A total of 288 HCV GT1b patients without baseline non-structural 5A (NS5A) resistance-associated substitution (RAS) treated with DCV/ASV were enrolled. Virologic response was measured at 12 weeks and 1 year after treatment completion. In cirrhotic patients, liver function, aspartate transaminase to platelet ratio index (APRI), FIB-4 index, fibrosis index (FI), and liver stiffness measurement (LSM) at baseline and 1 year after treatment completion were evaluated. RESULTS: SVR12 was obtained in 278 patients (96.5%). Six patients who checked NS5A RAS after treatment failure were RAS positive. Only one patient showed no durability of SVR. In cirrhotic patients who achieved SVR12 (n = 59), the changes of albumin (3.8 [2.2-4.7] to 4.3 [2.4-4.9] g/dL; P < 0.001), platelet count (99 [40-329] to 118 [40-399] × 10³/mm³; P < 0.001), APRI (1.8 [0.1-14.8] to 0.6 [0.1-4.8]; P < 0.001), FIB-4 index (5.45 [0.6-32.8] to 3.3 [0.4-12.2]; P < 0.001), FI (5.5 [0.6-32.8] to 3.3 [0.4-12.2]; P < 0.001), and LSM (17.2 [5.3-48.0] to 11.2 [3.7-28.1] kPa; P = 0.001) between baseline and 1 year after treatment completion were observed. CONCLUSION: DCV/ASV treatment for HCV GT1b infected patients without RAS achieved high SVR rates and showed durable SVR. Cirrhotic patients who achieved SVR12 showed the improvement of liver function and fibrosis markers.


Assuntos
Antivirais/uso terapêutico , Hepacivirus/genética , Hepatite C/tratamento farmacológico , Imidazóis/uso terapêutico , Isoquinolinas/uso terapêutico , Sulfonamidas/uso terapêutico , Resposta Viral Sustentada , Adulto , Aspartato Aminotransferases/sangue , Carbamatos , Farmacorresistência Viral , Quimioterapia Combinada , Feminino , Genótipo , Hepacivirus/isolamento & purificação , Humanos , Fígado/fisiologia , Cirrose Hepática/diagnóstico , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Pirrolidinas , RNA Viral/sangue , Resultado do Tratamento , Valina/análogos & derivados
7.
J Korean Med Sci ; 33(42): e264, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30310365

RESUMO

BACKGROUND: Hepatitis B virus (HBV) infection leads to hepatic and extrahepatic manifestations including chronic kidney disease (CKD). However, the association between HBV and CKD is not clear. This study investigated the association between chronic HBV infection and CKD in a nationwide multicenter study. METHODS: A total of 265,086 subjects who underwent health-check examinations in 33 hospitals from January 2015 to December 2015 were enrolled. HBV surface antigen (HBsAg) positive cases (n = 10,048), and age- and gender-matched HBsAg negative controls (n = 40,192) were identified. CKD was defined as a glomerular filtration rate (GFR) < 60 mL/min/1.73 m2 or proteinuria as at least grade 2+ of urine protein. RESULTS: HBsAg positive cases showed a significantly higher prevalence of GFR < 60 mL/min/1.73 m2 (3.3%), and proteinuria (18.9%) than that of the controls (2.6%, P < 0.001, and 14.1%, P < 0.001, respectively). In the multivariate analysis, HBsAg positivity was an independent factor associated with GFR < 60 mL/min/1.73 m2 along with age, blood levels of albumin, bilirubin, anemia, and hemoglobin A1c (HbA1c). Likewise, HBsAg positivity was an independent factor for proteinuria along with age, male, blood levels of bilirubin, protein, albumin, and HbA1c. A subgroup analysis showed that HBsAg positive men but not women had a significantly increased risk for GFR < 60 mL/min/1.73 m2. CONCLUSION: Chronic HBV infection was significantly associated with a GFR < 60 mL/min/1.73 m2 and proteinuria (≥ 2+). Therefore, clinical concern about CKD in chronic HBV infected patients, especially in male, is warranted.


Assuntos
Hepatite B Crônica/diagnóstico , Insuficiência Renal Crônica/diagnóstico , Adulto , Bilirrubina/sangue , Proteínas Sanguíneas/análise , Estudos de Casos e Controles , Feminino , Taxa de Filtração Glomerular , Hemoglobinas Glicadas/análise , Antígenos de Superfície da Hepatite B/sangue , Hepatite B Crônica/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Proteinúria/complicações , Proteinúria/epidemiologia , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/patologia , Estudos Retrospectivos , Fatores de Risco , Albumina Sérica/análise
8.
Dig Dis Sci ; 62(3): 808-816, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28035553

RESUMO

BACKGROUND: Sustained abnormal serum alanine aminotransferase (ALT) levels can increase the risk of hepatocellular carcinoma (HCC) in patients with chronic hepatitis B. AIM: This study is aimed to confirm the impact of rapid ALT normalization (≤30 IU/L) on HCC risk in patients with hepatitis B virus (HBV)-associated cirrhosis after entecavir (ETV) commencement. METHODS: A total of 578 treatment-naïve patients with HBV-associated cirrhosis (mean age 51 ± 9 years, male sex 63.3%) were treated with ETV for more than 1 year. Serum ALT and HBV DNA levels were measured at three time points (baseline, 6, and 12 months after ETV commencement) and subjected to risk factor analysis. RESULTS: Median follow-up after ETV commencement was 43 (12-98) months. Cumulative incidences of HCC at 1, 3, 5, and 7 years were 0.3, 8.5, 19.5, and 30.6%, respectively. Univariate Cox regression analysis showed that older age, abnormal ALT at 6 months or 12 months, and lower platelet count were significant risk factors for HCC. However, gender, HBeAg positivity, abnormal ALT levels or HBV DNA levels at baseline, and detectable HBV DNA at 6 or 12 months were not risk factors. Multivariate analysis showed that older age (P < 0.001), abnormal ALT at 12 months (P = 0.006), and lower platelet count (P = 0.034) were the risk factors for HCC. CONCLUSIONS: Abnormal serum ALT levels after ETV commencement are significant risk factor for HCC. Therefore, ALT should be rapidly normalized to minimize the risk of HCC development in patients with HBV-associated cirrhosis.


Assuntos
Alanina Transaminase , Carcinoma Hepatocelular/diagnóstico , Guanina/análogos & derivados , Hepatite B Crônica , Cirrose Hepática/sangue , Neoplasias Hepáticas/diagnóstico , Adulto , Fatores Etários , Alanina Transaminase/análise , Alanina Transaminase/sangue , Antivirais/administração & dosagem , Antivirais/efeitos adversos , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/etiologia , Feminino , Guanina/administração & dosagem , Guanina/efeitos adversos , Hepatite B Crônica/complicações , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/epidemiologia , Humanos , Incidência , Cirrose Hepática/etiologia , Neoplasias Hepáticas/etiologia , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas/estatística & dados numéricos , Prognóstico , República da Coreia/epidemiologia , Medição de Risco
9.
J Gastroenterol Hepatol ; 30(12): 1775-81, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26095700

RESUMO

BACKGROUND AND AIM: Entecavir (ETV) induces biochemical and histologic improvement of the liver in patients with chronic hepatitis B. This study aimed to confirm that 2 years of ETV treatment improves liver function and non-invasive fibrosis markers in patients with hepatitis B virus (HBV)-associated cirrhosis. METHODS: A total 472 naïve patients with HBV-associated cirrhosis was treated with ETV for at least 2 years, between March 2007 and December 2012. Model for end-stage liver disease and Child-Pugh (CP) score were used to evaluate the improvement of liver function. Aspartate transaminase to platelet ratio index, FIB-4 index, and fibrosis index were used to evaluate the improvement of fibrosis. RESULTS: The final 370 of 472 patients with HBV-associated cirrhosis were enrolled. Mean age was 51 ± 10 years, and 240 patients (64.9%) were men. The distribution of CP class was 71.1% in A, 24.6% in B, and 4.3% in C. Mean end-stage liver disease and CP score changed over the study period from 8.5 ± 4.6 to 6.2 ± 4.2 (P < 0.001) and from 6.2 ± 1.6 to 5.6 ± 0.9 (P < 0.001), respectively. Aspartate transaminase to platelet ratio index, FIB-4 index, and fibrosis index changed from 3.6 ± 4.5 to 1.5 ± 1.5 (P < 0.001), from 7.0 ± 6.2 to 3.9 ± 2.8 (P < 0.001), and from 3.3 ± 0.9 to 2.5 ± 1.1 (P < 0.001), respectively. CONCLUSIONS: After 2 years of treatment, ETV improves liver function and non-invasive fibrosis markers in patients with HBV-associated cirrhosis.


Assuntos
Guanina/análogos & derivados , Hepatite B/tratamento farmacológico , Cirrose Hepática/tratamento farmacológico , Fígado/patologia , Adulto , Aspartato Aminotransferases/sangue , Biomarcadores/sangue , Feminino , Fibrose , Guanina/administração & dosagem , Hepatite B/complicações , Hepatite B/patologia , Hepatite B/fisiopatologia , Humanos , Cirrose Hepática/etiologia , Cirrose Hepática/patologia , Cirrose Hepática/fisiopatologia , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento
10.
Intervirology ; 57(5): 239-47, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24993731

RESUMO

OBJECTIVE: This study was designed to prospectively evaluate the antiviral responses and evolution of resistance mutations during adefovir (ADV) plus lamivudine (LMV) therapy in patients with entecavir (ETV)-resistant hepatitis B virus (HBV) infection. METHODS: Twenty chronic hepatitis B (CHB) patients who had been receiving ETV for more than 6 months and developed virologic breakthrough due to ETV resistance were consecutively enrolled. RESULTS: Patients received ADV plus LMV therapy for 12 months. The baseline mean serum HBV DNA level was 5.59 ± 1.28 log10 IU/ml. The rtT184L/I/A/F (50%), rtS202G (25%) and mixed ETV-resistant mutations (25%) were detected at enrollment. The mean reduction in serum HBV DNA levels from baseline to 12 months was -2.3 ± 1.06 log10 IU/ml (p < 0.001). Seventeen patients were followed up for the full 12 months, and complete virologic response (HBV DNA <20 IU/ml) was observed in 4 patients (23.5%). Among the remaining 13 patients who still had detectable HBV DNA, 7 patients showed disappearance of ETV-resistant mutations or reduction of the proportion of ETV-resistant mutants. An ADV- and LMV-resistant mutant (rtA181T) emerged in 2 patients (11.7%). CONCLUSIONS: ADV plus LMV combination therapy suppresses ETV-resistant mutants in the viral population and significantly reduces serum HBV DNA levels in ETV-resistant CHB patients.


Assuntos
Adenina/análogos & derivados , Antivirais/farmacologia , Antivirais/uso terapêutico , Farmacorresistência Viral , Guanina/análogos & derivados , Hepatite B Crônica/tratamento farmacológico , Lamivudina/uso terapêutico , Organofosfonatos/uso terapêutico , Adenina/uso terapêutico , Adulto , Idoso , DNA Viral/sangue , Quimioterapia Combinada , Feminino , Guanina/farmacologia , Vírus da Hepatite B/classificação , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/genética , Vírus da Hepatite B/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Estudos Prospectivos , Soro/virologia , Resultado do Tratamento , Carga Viral
11.
Appl Microbiol Biotechnol ; 98(22): 9187-98, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25301586

RESUMO

Hypericum perforatum L. (St. John's wort), a perennial flowering plant native to Europe, is widely used as a medicinal plant and has a long history of its use in the treatment of various ailments. Currently, H. perforatum is widely used as an herbal remedy for the treatment of mild to moderate depression. Hypericins are natural napthodianthrone compounds produced from H. perforatum (St. John's wort) which are having antitumor, antiviral (i.e., against human immunodeficiency and hepatitis C virus), antineoplastic, and antidepressant properties. Currently, field-grown plant materials are generally used for the commercial production of hypericins. It has been reported that hypericin accumulation in natural plants is influenced by different ecological and environmental conditions including light intensity, nitrogen availability, temperature, seasons, and growing regions. Therefore, up to 17-fold and 13-fold differences in hypericin and pseudohypericin amounts, respectively, are reported in different phytopharmaceutical preparations. Plant cell and organ cultures are effective systems for producing natural products, and attempts were made for the production of biomass and stable concentrations of hypericins through in vitro cultures of H. perforatum. Cell, callus, shoot, plantlet, and adventitious root cultures have been established and various chemical and physical factors which influence the biomass and secondary metabolite accumulation have been investigated. Large-scale plantlet and adventitious root cultures have also been attempted in H. perforatum in bioreactors, and various strategies have been applied for the production of higher biomass and secondary products. This review describes the biotechnological approaches employed for the production of hypericins and focuses upon the challenges and future prospects.


Assuntos
Produtos Biológicos/metabolismo , Biotecnologia/métodos , Hypericum/crescimento & desenvolvimento , Hypericum/metabolismo , Perileno/análogos & derivados , Tecnologia Farmacêutica/métodos , Antracenos , Técnicas de Cultura de Células , Perileno/metabolismo
12.
Appl Microbiol Biotechnol ; 98(18): 7707-17, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25077780

RESUMO

Caffeic acid derivatives (CADs) are a group of bioactive compounds which are produced in Echinacea species especially Echinacea purpurea, Echinacea angustifolia, and Echinacea pallida. Echinacea is a popular herbal medicine used in the treatment of common cold and it is also a prominent dietary supplement used throughout the world. Caffeic acid, chlorogenic acid (5-O-caffeoylquinic acid), caftaric acid (2-O-caffeoyltartaric acid), cichoric acid (2, 3-O-dicaffeoyltartaric acid), cynarin, and echinacoside are some of the important CADs which have varied pharmacological activities. The concentrations of these bioactive compounds are species specific and also they vary considerably with the cultivated Echinacea species due to geographical location, stage of development, time of harvest, and growth conditions. Due to these reasons, plant cell and organ cultures have become attractive alternative for the production of biomass and caffeic acid derivatives. Adventitious and hairy roots have been induced in E. pupurea and E. angustifolia, and suspension cultures have been established from flask to bioreactor scale for the production of biomass and CADs. Tremendous progress has been made in this area; various bioprocess methods and strategies have been developed for constant high-quality productivity of biomass and secondary products. This review is aimed to discuss biotechnological methods and approaches employed for the sustainable production of CADs.


Assuntos
Biotecnologia , Ácidos Cafeicos/metabolismo , Echinacea/química , Succinatos/metabolismo , Reatores Biológicos , Cinamatos/metabolismo , Glicosídeos/metabolismo
13.
Appl Microbiol Biotechnol ; 98(17): 7319-29, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25005060

RESUMO

Eleutherosides, the phenylpropanoid and lignan glycosides, are the active ingredients accumulated in the roots and stems of Eleutherococcus species and in Eleutherococcus senticosus in particular. Syringin (=eleutheroside B) and (-) syringaresinol-di-O-ß-D-glucoside (=eleutheroside E) appear as the most important bioactive compounds which are used as adaptogens, besides their abundant antidiabetic and anticancer properties. As the availability of "Eleuthero" is becoming increasingly limited because of its scanty natural distribution, the production of these compounds by biotechnological means has become an attractive alternative. In E. senticosus and other closely related species, Eleutherococcus sessiliflorus, Eleutherococcus chiisanensis, and Eleutherococcus koreanum, organogenic cultures have been induced for the production of eleutherosides. Bioreactor cultures have been established and various parameters, which influence on the accumulation of biomass and secondary metabolites, have been thoroughly investigated. Pilot-scale cultures have also been accomplished for the large-scale production of somatic embryos containing abundant amounts of eleutherosides. This review describes the biotechnological approaches and challenges for the production of eleutherosides.


Assuntos
Eleutherococcus/crescimento & desenvolvimento , Eleutherococcus/metabolismo , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/metabolismo , Reatores Biológicos , Biotecnologia/métodos
14.
Appl Microbiol Biotechnol ; 98(14): 6243-54, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24859520

RESUMO

Panax ginseng C.A. Meyer (ginseng) is a well-known medicinal plant that has been traditionally used in the oriental countries for centuries. Wild ginseng is a scarce and rare commodity. Field cultivation of the ginseng plant is a time-consuming and labor-intensive process. Ginsenosides, a group of glycosylated triterpenes, also known as saponins, are the principal bioactive constituents of ginseng. The use of cell and organ culture processes has been sought as a potential alternative for the efficient mass production of ginseng raw material. Various bioprocessing strategies have been developed to date. Cells and adventitious roots have been cultured in large-scale bioreactors and various strategies have been developed accordingly for the enhancement of biomass and ginsenoside accumulation. This review highlights the recent progress in the cultivation of ginseng cell and organ cultures for the production of ginsenosides from bioreactor cultures. In addition, the metabolism and biochemistry of ginsenoside biosynthesis, genomic and proteomic studies in ginseng, metabolic engineering, biosafety, toxicological evaluation, and efficacy assessment of ginseng raw material are also summarized and thoroughly discussed.


Assuntos
Biotecnologia/métodos , Ginsenosídeos/isolamento & purificação , Ginsenosídeos/metabolismo , Reatores Biológicos , Técnicas de Cultura de Células/métodos , Panax/crescimento & desenvolvimento , Panax/metabolismo
15.
Plant J ; 70(3): 480-91, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22171964

RESUMO

Glandular trichomes are the phytochemical factories of plants, and they secrete a wide range of commercially important natural products such as lipids, terpenes and flavonoids. Herein, we report that the Nicotiana tabacum LTP1 (NtLTP1) gene, which is specifically expressed in long glandular trichomes, plays a role in lipid secretion from trichome heads. NtLTP1 mRNA is abundantly transcribed in trichomes, but NtLTP3, NtLTP4 and NtLTP5 are not. In situ hybridization revealed that NtLTP1 mRNAs accumulate specifically in long trichomes and not in short trichomes or epidermal cells. X-gluc staining of leaves from a transgenic plant expressing the NtLTP1 promoter fused to a GUS gene revealed that NtLTP1 protein accumulated preferentially on the tops of long glandular trichomes. GFP fluorescence from transgenic tobacco plants expressing an NtLTP1-GFP fusion protein was localized at the periphery of cells and in the excreted liquid droplets from the glandular trichome heads. In vitro assays using a fluorescent 2-p-toluidinonaphthalene-6-sulfonate probe indicated that recombinant NtLTP1 had lipid-binding activity. The overexpression of NtLTP1 in transgenic tobacco plants resulted in the increased secretion of trichome exudates, including epicuticular wax. In transgenic NtLTP1-RNAi lines, liquid secretion from trichomes was strongly reduced, but epicuticular wax secretion was not altered. Moreover, transgenic tobacco plants overexpressing NtLTP1 showed increased protection against aphids. Taken together, these data suggest that NtLTP1 is abundantly expressed in long glandular trichomes, and may play a role in lipid secretion from long glandular trichomes.


Assuntos
Proteínas de Transporte/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Metabolismo dos Lipídeos , Nicotiana/metabolismo , Epiderme Vegetal/metabolismo , Animais , Afídeos/fisiologia , Proteínas de Transporte/genética , DNA Complementar/genética , Resistência à Doença/genética , Dados de Sequência Molecular , Especificidade de Órgãos , Epiderme Vegetal/genética , Epiderme Vegetal/ultraestrutura , Exsudatos de Plantas/metabolismo , Folhas de Planta/genética , Folhas de Planta/metabolismo , Folhas de Planta/ultraestrutura , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Brotos de Planta/genética , Brotos de Planta/metabolismo , Brotos de Planta/ultraestrutura , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas/genética , RNA de Plantas/genética , Proteínas Recombinantes de Fusão , Nicotiana/genética , Nicotiana/ultraestrutura , Ceras/metabolismo
16.
Langmuir ; 29(32): 10059-65, 2013 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-23875615

RESUMO

We report a first application of vertical small-angle X-ray scattering to investigate the drying process of a colloidal suspension by overcoming gravity related restrictions. From the observation of the drying behavior of charge-stabilized colloidal silica in situ, we find the solidification of the colloidal particles exhibits an initial ordering, followed by a sudden aggregation when they overcome an electrostatic energy barrier. The aggregation can be driven not only by capillary pressure but also by thermal motion of the particles. The dominating contribution is determined by the magnitude of the energy barrier at the transition, which significantly decreases during drying due to an increased ionic strength.


Assuntos
Dióxido de Silício/química , Coloides/química , Espalhamento a Baixo Ângulo , Suspensões/química , Difração de Raios X
17.
Liver Int ; 33(2): 244-54, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23295056

RESUMO

BACKGROUND: Management of lamivudine-resistant chronic hepatitis B (CHB) remains challenging, as inappropriate choice of treatment may cause multidrug resistance. Until now, randomized trials directly comparing adding adefovir and switching to entecavir monotherapy have not been reported. AIMS: This multicentre prospective randomized study was designed to compare the efficacy of these two strategies. METHODS: Two hundred and nineteen lamivudine-resistant CHB patients were randomized to either adefovir-lamivudine combination group or entecavir monotherapy group (n = 110 vs. 109), and followed up for 24 months. RESULTS: One hundred and eighty patients completed this study. At month 24, virological response rate [hepatitis B virus (HBV) DNA <60 IU/ml] was higher in the adefovir-lamivudine combination group compared with entecavir group (56.7% vs. 40%, P = 0.025), although biochemical and serological response rates were not significantly different. Genotypic resistance (9.2% vs. 24.6%, P = 0.005) and combined viral breakthrough (2.0% vs. 17.6%, P < 0.001) were more frequent in the entecavir group. However, by subgroup analysis, virological response rates were not significantly different between the two therapies in HBeAg-positive patients (44.9% vs. 35.7%, P = 0.268) or in patients with high baseline HBV DNA (≥7 log IU/ml) (40.7% vs. 31.3%, P = 0.320) at month 24. CONCLUSION: This study showed that adefovir-lamivudine combination provides significantly higher antiviral efficacy and the lower resistance rate compared with the entecavir monotherapy in the management of lamivudine-resistant CHB. However, it had limited efficacy in HBeAg-positive patients or in patients with high baseline HBV DNA.


Assuntos
Antivirais/uso terapêutico , Hepatite B Crônica/tratamento farmacológico , Hepatite B/genética , Inibidores da Transcriptase Reversa/uso terapêutico , Adenina/análogos & derivados , Adulto , Análise de Variância , DNA Viral/sangue , Farmacorresistência Viral , Feminino , Seguimentos , Guanina/análogos & derivados , Humanos , Imunoensaio , Lamivudina , Masculino , Pessoa de Meia-Idade , Oligonucleotídeos/genética , Organofosfonatos , Estudos Prospectivos , República da Coreia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Resultado do Tratamento
18.
J Clin Gastroenterol ; 47(7): 644-50, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23442843

RESUMO

BACKGROUND: Genetic variations in interleukin 28B (IL28B) have been strongly associated with a sustained virological response (SVR) in European and African-American patients. Genetic variation of IL28B was investigated in healthy controls and chronic hepatitis C (CHC) patients, and the treatment response in the CHC patients was analyzed according to IL28B polymorphism in the Korean population. METHODS: IL28B polymorphisms (rs12979860 and rs8099917) were studied in 200 healthy controls and in 167 CHC patients who were treated with peginterferon-α and ribavirin. RESULTS: The prevalence of rs12979860 in healthy controls is as follows: the CC-genotype was 88.5%, the CT-genotype was 11.5%, and the TT-genotype was not found. The prevalence of rs8099917 in healthy controls is as follows: the TT-genotype was 89.5%, the TG-genotype was 10.5%, and the GG-genotype was not found. The CC-genotype of rs12979860 and the TT-genotype of rs8099917 were found to be closely related (linkage disequilibrium; D'=1.0, χ =0.9082). In 106 CHC patients treated with peginterferon and ribavirin, the SVR was 67.2% (n=58) for 1b, 91.6% (n=47) for 2a. In hepatitis C virus (HCV) genotype 1b with respect to rs12979860, the SVR in CC-genotype was 72.9% and that in CT-genotype was 40.0%. On investigating predictive factors for SVR, pretreatment low-HCV RNA levels, HCV genotype non-1, early virological response, and also the IL28B CC-genotype for rs12979860 were good indicators of an SVR. CONCLUSIONS: In Korea, genetic variation of IL28B is different from that in western countries in view of high prevalence of rs12979860 CC-genotype. It seems likely that a high SVR in Korean patients with genotype 1 CHC patients is due to the genetic polymorphism in IL28B.


Assuntos
Antivirais/uso terapêutico , Povo Asiático/genética , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/genética , Interleucinas/genética , Polimorfismo de Nucleotídeo Único/genética , Adulto , Estudos de Casos e Controles , Primers do DNA/química , Quimioterapia Combinada , Feminino , Genótipo , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/virologia , Humanos , Interferon alfa-2 , Interferon-alfa/uso terapêutico , Interferons , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/uso terapêutico , Reação em Cadeia da Polimerase , Prevalência , Proteínas Recombinantes/uso terapêutico , Estudos Retrospectivos , Ribavirina/uso terapêutico , Carga Viral/efeitos dos fármacos
19.
BMC Gastroenterol ; 13: 74, 2013 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-23627926

RESUMO

BACKGROUND: Two recent Italian studies suggested that Pegylated-interferon (PEG-IFN) alfa-2a achieves a higher sustained virological response (SVR) rate than PEG-IFN alfa-2b. We intended to compare the efficacy and safety of PEG-IFN alfa-2a with those of PEG-IFN alfa-2b in Korean patients with chronic hepatitis C virus (HCV). METHODS: This retrospective, multi-center trial was conducted on 661 treatment-naïve chronic HCV patients. Patients received PEG-IFN alfa-2a (180 µg/week; n=402) or PEG-IFN alfa-2b (1.5 µg/kg/week; n=259) with ribavirin (800-1200 mg/day) for 24 or 48 weeks according to HCV genotypes. RESULTS: Early virologic response and sustained virologic response (SVR) rates were not significantly different between two PEG-IFN groups both in patients with HCV genotype 1 (all P-values>0.05) and 2/3 (all P-values>0.05). SVR rates were not different between two groups in each categorized baseline characteristics: age (years) (≤ 50 and >50), HCV viral load (IU/mL) (≤ 7 × 10(5) and >7 × 10(5)), and hepatic fibrosis (F0-2 and F3-4) (all P-values >0.05). In additional analysis for 480 patients who sufficiently complied with treatment doses and duration (80/80/80 rule) and propensity-score matched analysis, SVR rates were not different between two groups both in patients with HCV genotype 1 and 2/3 (all P-values >0.05). Adverse event rates were similar between two groups. CONCLUSIONS: Unlike the Western data, efficacy and safety of PEG-IFN alfa-2a were similar to those of PEG-IFN alfa-2b in chronically HCV-infected Korean patients regardless of age, HCV viral load, and hepatic fibrosis.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico , Antivirais/efeitos adversos , Quimioterapia Combinada , Feminino , Hepacivirus/genética , Hepatite C Crônica/virologia , Humanos , Interferon alfa-2 , Interferon-alfa/efeitos adversos , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/efeitos adversos , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/uso terapêutico , República da Coreia , Estudos Retrospectivos , Ribavirina/uso terapêutico , Carga Viral
20.
Hepatogastroenterology ; 60(124): 842-9, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23186591

RESUMO

BACKGROUND/AIMS: Sequential antiviral therapy for chronic hepatitis B may lead to the selection of multidrug-resistant mutation. This study was carried out to assess the efficacy of entecavir in patients that have experienced adefovir monotherapy failure after the development of lamivudine resistance. METHODOLOGY: Fifty-three patients with confirmed genotypic lamivudine-resistant chronic hepatitis B were treated with entecavir. Thirty patients were switched to entecavir directly (LAM-ETV group), whereas the remaining 23 were adefovir-refractory patients who were switched to entecavir (LAM-ADV-ETV group). These 23 patients included 9 patients with inadequate response (ADV-I subgroup) and 14 that exhibited adefovir resistance (ADV-R subgroup). RESULTS: Significantly greater reductions in HBV DNA levels were observed after 24, 48 and 72 weeks of entecavir therapy in the LAM-ETV group than in the LAM-ADV-ETV group, respectively. However, between these two groups at 48 and 72 weeks, no significant differences were observed in cumulative proportions of virological response or breakthrough, respectively. Furthermore, efficacy of entecavir was not significantly different in the ADV-I and ADV-R subgroups. Four patients in the LAM-ETV group and six patients in the LAM-ADV-ETV group developed genotypic resistance to entecavir. CONCLUSIONS: Entecavir therapy is less effective in adefovir-refractory patients with prior lamivudine resistance than in lamivudine-resistant patients.


Assuntos
Adenina/análogos & derivados , Antivirais/farmacologia , Farmacorresistência Viral/genética , Guanina/análogos & derivados , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/genética , Lamivudina/farmacologia , Organofosfonatos/farmacologia , Adenina/farmacologia , Quimioterapia Combinada , Feminino , Genótipo , Guanina/farmacologia , Humanos , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
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