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1.
Eur Rev Med Pharmacol Sci ; 24(18): 9760-9764, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33015823

RESUMO

OBJECTIVE: Patients with cancer are usually immunosuppressive and susceptible to COVID-19 infection. Asymptomatic COVID-19 cases are infective and cannot be identified by symptom-based screening. There is an urgent need to control virus spread by asymptomatic carriers at cancer centres. We aim to describe the characteristics, screening methods, and outcomes of cancer patients with asymptomatic COVID-19 infection and to further explore anti-tumour treatment for this population. PATIENTS AND METHODS: We reviewed patients with cancer who were admitted to Hubei Cancer Hospital in Wuhan from February 1, 2020, to April 4, 2020. We collected demographic data, laboratory findings, treatment information, nucleic acid and serum test results, chest computed tomography (CT) information and survival status of cancer patients diagnosed with asymptomatic COVID-19 infection. RESULTS: A total of 16 cancer patients with asymptomatic COVID-19 infection were confirmed. The most common cancer type was breast cancer. The blood cell counts of most patients were in the normal range. Lymphocytes of 100% of asymptomatic carriers were in the normal range. Thirteen (81.3%) patients were positive for virus-specific IgM antibodies, and three (18.8%) were positive by PCR; only one (6.3%) patient showed novel coronavirus pneumonia features on CT. Three (18.3%) patients died, and the cause of death was considered malignancy caused by delaying anti-tumour treatment. CONCLUSIONS: Our study shows that the lymphocytes of 100% of asymptomatic carriers were in the normal range. This result indicates that the host immunity of asymptomatic carriers is not significantly disrupted by COVID-19. Single PCR detection is not sufficient to screen among asymptomatic individuals, and a combination of PCR tests, serological tests and CT is of great importance. Unless the tumour is life-threatening or rapidly progressing, we advise restarting active anti-tumour therapy after PCR tests become negative.


Assuntos
Doenças Assintomáticas/epidemiologia , Institutos de Câncer/estatística & dados numéricos , Infecções por Coronavirus/diagnóstico , Pneumonia Viral/diagnóstico , Idoso , Betacoronavirus , COVID-19 , China/epidemiologia , Infecções por Coronavirus/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/complicações , Neoplasias/tratamento farmacológico , Pandemias , Pneumonia Viral/complicações , SARS-CoV-2 , Taxa de Sobrevida
2.
Ann R Coll Surg Engl ; 102(5): e102-e104, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32159370

RESUMO

Epigastric hernia involving the falciform ligament is exceptionally rare. Most reported cases are incisional hernia secondary to prior abdominal surgery. We report a case of primary falciform ligament herniation into the epigastric region repaired by the laparoscopic preperitoneal approach. In this case, an accompanying vessel along the herniated falciform ligament was identified. This finding provides a basis for the hypothesis of a perforating vessel piercing the linea alba and thereby creating a weak point for hernia protrusion (Moschowitz theory). The patient had an uneventful recovery and was discharged home on the postoperative day two. A laparoscopic preperitoneal approach is feasible for the repair of primary falciform ligament herniation. The magnified endoscopic view enables surgeons to achieve definite repair without missing occult defects.


Assuntos
Parede Abdominal/patologia , Hérnia Abdominal/cirurgia , Laparoscopia , Ligamentos/patologia , Parede Abdominal/diagnóstico por imagem , Parede Abdominal/cirurgia , Idoso , Feminino , Hérnia Abdominal/diagnóstico , Hérnia Abdominal/patologia , Humanos , Ligamentos/diagnóstico por imagem , Resultado do Tratamento , Ultrassonografia
3.
Aliment Pharmacol Ther ; 45(5): 744-753, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28074540

RESUMO

BACKGROUND: Liver biopsy is the gold standard in evaluating liver diseases but is susceptible to complications. Safety data on aspiration needle biopsies remain limited. AIM: To evaluate the safety of percutaneous liver biopsy performed with Klatskin needle. METHODS: Clinical and biochemical data were retrospectively retrieved from sequential subjects who underwent liver biopsy with Klatskin needle from 1978 to 2015. Subjects with complications underwent thorough chart reviews for hospital course. RESULTS: Of 3357 biopsies performed, complications occurred in 135 (4%) biopsies with 33 (1%) resulting in major complications. Severe pain occurred in 78 (2.3%) subjects and bleeding occurred in 21 (0.6%) subjects. Biliary injury occurred in 8 (0.2%) biopsies. Three subjects died as a result of massive intraperitoneal bleeding. Compared to viral hepatitis, biopsies performed with certain diagnosis had significantly higher odds of major complications: NRH (OR: 17), DILI (OR: 20), GVHD (OR: 32) and HCC (OR: 34). Subjects with major complications had higher pre-biopsy median AP (153 vs. 78 U/L, P < 0.001), ALT (105 vs. 64 U/L, P < 0.05), AST (62 vs. 47 U/L, P < 0.02), along with marginally lower total bilirubin (1.0 vs. 0.7 mg/dL, P < 0.01) and albumin (3.7 vs. 4.0 g/dL, P < 0.001). By multivariate backward logistic regression, platelets ≤100 K/µL and aPTT >35 were independent risk factors of post-biopsy bleeding. CONCLUSION: Klatskin needle liver biopsies are safe with rare procedural morbidity. Our data suggests certain acutely ill subjects and those with systemic illnesses may be at higher risk of major complications. Clinicians should weigh the risks and benefits of liver biopsy in these patients with other alternative approaches.


Assuntos
Biópsia por Agulha/efeitos adversos , Hemorragia/etiologia , Hepatopatias/diagnóstico , Dor/etiologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Agulhas , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
4.
Aliment Pharmacol Ther ; 45(1): 127-138, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27813124

RESUMO

BACKGROUND: Serum fibrosis markers are useful in staging chronic hepatitis B (HBV) and C (HCV) virus but have not been evaluated in chronic hepatitis D virus (HDV). AIM: To evaluate the utility of serum fibrosis markers [fibrosis-4 score (FIB-4), aspartate aminotransferase (AST) to alanine aminotransferase (ALT) ratio, aspartate aminotransferase ratio (AAR), age-platelet index (API), AST-to-platelet-ratio-index (APRI) and Hui score] in HDV infection. METHODS: Clinical and histologic laboratory data from HBV, HCV and HDV patients were evaluated and serum fibrosis markers were calculated. The ability of fibrosis markers to detect advanced fibrosis (Ishak ≥4) and cirrhosis (Ishak = 6) were evaluated and compared between viral infections. RESULTS: A total of 1003 subjects (HCV = 701, HBV = 240 and HDV = 62) with mean age of 46 ± 11 and 66% male were evaluated. HDV subjects had higher ALT and AST than HCV and lower platelets than both HBV and HCV. Histologically, HDV had the greatest percentage of Ishak ≥4 and necroinflammation. FIB-4 performed best in detecting advanced fibrosis and cirrhosis in all viral cohorts. In HDV, area under the receiver operator curve (AUROC) 95% confidence intervals for detecting advanced fibrosis were: FIB-4 = 0.70 (0.55-0.84), API = 0.69 (0.55-0.82), APRI = 0.68 (0.54-0.82), Hui score = 0.63 (0.49-0.78), AAR = 0.63 (0.48-0.77). The AUROC for detecting cirrhosis in HDV were: FIB-4 = 0.83 (0.69-0.97), API = 0.80 (0.66-0.95), APRI = 0.75 (0.61-0.89), Hui score = 0.70 (0.49-0.91) and AAR = 0.70 (0.48-0.93). Adjustment of published cut-offs led to marginal improvements in FIB4 for advanced fibrosis and of APRI for cirrhosis in HDV. CONCLUSIONS: Serum fibrosis markers have lower performance accuracy in chronic HDV infected patients compared to HBV and HCV patients. Other noninvasive fibrosis markers should be explored to assist in the management of these patients.


Assuntos
Hepatite D Crônica/sangue , Hepatite D Crônica/diagnóstico , Vírus Delta da Hepatite , Cirrose Hepática/sangue , Cirrose Hepática/diagnóstico , Adulto , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Biomarcadores/sangue , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas/métodos , Estudos Retrospectivos
5.
Eur Rev Med Pharmacol Sci ; 20(18): 3818-3824, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27735036

RESUMO

OBJECTIVE: The aim of this study was to investigate the target gene of miR-494 and its roles in tumor growth of gastric cancer (GC). PATIENTS AND METHODS: Expression of miR-494 was evaluated by quantitative real-time polymerase chain reaction (qRT-PCR) in gastric cancer tissues and cell lines. Then, luciferase reporter assay was used to elucidate whether insulin-like growth factor 1 receptor (IGF1R) is a target gene of miR-494. Finally, the roles and mechanism of miR-494 in the regulation of tumor invasion were further investigated. RESULTS: Relative miR-494 level was found to be significantly lower in patients with GC than healthy controls (p < 0.01). Over-expression of miR-494 could inhibit gastric cancer cell proliferation, migration, and invasion in vitro. Furthermore, we demonstrated that miR-494 binds to the 3'-untranslated region (UTR) of IGF1R and inhibits the expression of the IGF1R protein. CONCLUSIONS: Our data showed that miR-494 acted as a tumor suppressor in GC.


Assuntos
MicroRNAs/genética , Receptor IGF Tipo 1 , Neoplasias Gástricas , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Reação em Cadeia da Polimerase em Tempo Real
7.
Genes Immun ; 16(5): 321-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26020282

RESUMO

IFNL4 is linked to hepatitis C virus treatment response and type III interferons (IFNs). We studied the functional associations among hepatic expressions of IFNs and IFN-stimulated genes (ISGs), and treatment response to peginterferon and ribavirin. Type I IFNs (IFNA1, IFNB1), type II (IFNG), type III (IFNL1, IFNL2/3), IFNL4 and ISG hepatic expressions were measured by qPCR from in 65 chronic hepatitis C (CHC) patients whose IFNL4-associated rs368234815 and IFNL3-associated rs12989760 genotype were determined. There was a robust correlation of hepatic expression within type I and type III IFNs and between type III IFNs and IFNL4 but no correlation between other IFN types. Expression of ISGs correlated with type III IFNs and IFNL4 but not with type I IFNs. Levels of ISGs and IFNL2/3 mRNAs were lower in IFNL3 rs12979860 CC patients compared with non-CC patients, and in treatment responders, compared with nonresponders. IFNL4-ΔG genotype was associated with high ISG levels and nonresponse. Hepatic levels of ISGs in CHC are associated with IFNL2/3 and IFNL4 expression, suggesting that IFNLs, not other types of IFNs, drive ISG expression. Hepatic IFNL2/3 expression is functionally linked to IFNL4 and IFNL3 polymorphisms, potentially explaining the tight association among ISG expression and treatment response.


Assuntos
Genótipo , Hepatite C Crônica/genética , Fatores Reguladores de Interferon/genética , Interferons/genética , Fígado/metabolismo , Fenótipo , Adulto , Antivirais/farmacologia , Antivirais/uso terapêutico , Feminino , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/metabolismo , Humanos , Fatores Reguladores de Interferon/metabolismo , Interferons/metabolismo , Interferons/farmacologia , Interferons/uso terapêutico , Fígado/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Ribavirina/farmacologia , Ribavirina/uso terapêutico
8.
Aliment Pharmacol Ther ; 40(1): 93-104, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24815494

RESUMO

BACKGROUND: Chronic delta hepatitis virus (HDV) infection rapidly progresses to cirrhosis. Treatment with peginterferon for up to 2 years is often without durable response. AIM: To examine the efficacy and safety of long-term peginterferon in achieving a durable response. METHODS: Treatment was initiated with 180 µg/week of peginterferon alfa-2a with titration to a maximal tolerable dose, for up to 5 years. Liver biopsies and hepatic venous pressure gradients (HVPG) were evaluated at baseline, 1, 3 and 5 years. The primary endpoint was histological improvement or loss of serum HDV and HBsAg at 3 years. RESULTS: Thirteen patients were treated for a median of 140 weeks (6-260) with an average peginterferon dose of 180 µg/week (90-270). At baseline, most had advanced disease (median Ishak fibrosis = 3) with portal hypertension (HVPG = 10.2 ± 6 mmHg). Five of 13 patients (39%) achieved the primary endpoint, with three seroconverting for HBsAg after 24, 37 and 202 weeks of treatment. Histological inflammation improved after 1 year, (median HAI: 10 vs. 7, P = 0.01) with persistence in 4/5 patients at 3 years (median HAI: 7.5). Greatest improvements occurred in the first year. Baseline bilirubin and HBsAg levels were significantly lower in virological responders than nonresponders. After 12 weeks, virological responders had a significant decline in HBsAg (1.5 log10 IU/mL, P = 0.05). CONCLUSION: Despite increased doses and duration of therapy, treatment of chronic HDV with peginterferon remains unsatisfactory. Quantitative measures of HBsAg may be an important biomarker of early response to peginterferon therapy in chronic delta hepatitis virus infection.


Assuntos
Antivirais/uso terapêutico , Antígenos de Superfície da Hepatite B/sangue , Hepatite D Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico , Adolescente , Adulto , Idoso , Inibidores da Angiogênese/uso terapêutico , Antivirais/administração & dosagem , Antivirais/efeitos adversos , Progressão da Doença , Relação Dose-Resposta a Droga , Feminino , Hepatite D Crônica/complicações , Humanos , Interferon-alfa/administração & dosagem , Interferon-alfa/efeitos adversos , Cirrose Hepática/etiologia , Cirrose Hepática/virologia , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/efeitos adversos , Estudos Prospectivos , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/uso terapêutico , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
9.
Aliment Pharmacol Ther ; 37(9): 887-94, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23461575

RESUMO

BACKGROUND: Although the short-term benefits of a sustained virological response (SVR) to interferon-based therapies of chronic hepatitis C (CHC) are well known, the long-term consequences of SVR are less clear. AIM: To assess changes in markers of disease activity and fibrosis in patients followed up to 23 years post-SVR. METHODS: The first 103 SVR patients (from 1984 to 2003) at the National Institutes of Health Clinical Center were evaluated. Serum markers before treatment and at the last visit were compared. Evaluations after 2007 included transient elastography (TE). RESULTS: Of 103 patients, three subsequently relapsed 0.7, 6.3 and 6.5 years post therapy. The remaining 100 patients (56 men, mean age 56 years) maintained SVR at final follow-up. No patients developed hepatic decompensation, but one with pre-treatment cirrhosis died 12 years post SVR of hepatocellular carcinoma. In comparison to pre-treatment values, markers improved at follow-up, including mean ALT (152-27 U/L), AST (87-24 U/L), alkaline phosphatase (78-69 U/L), IgG (1463-1113 mg/dL), platelet count (209 000-239 000/µL) and AST to platelet count ratio index (APRI: 1.31-0.33). TE was performed in 69 patients and was normal (<7.0 kPA) in 60%, moderately elevated (7.1-13.8) in 31% and cirrhotic range (>13.8) in 9%. TE and platelet counts at follow-up correlated with fibrosis on pre-treatment liver biopsy (P < 0.001). CONCLUSIONS: In 97% of patients with CHC, SVR is durable without evidence of disease progression, although some degree of hepatic fibrosis may persist and patients with pre-treatment cirrhosis are at continuing low risk for hepatocellular carcinoma.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico , Ribavirina/uso terapêutico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Feminino , Seguimentos , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/sangue , Hepatite C Crônica/virologia , Humanos , Interferon alfa-2 , Testes de Função Hepática , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/uso terapêutico , Resultado do Tratamento , Adulto Jovem
10.
Aliment Pharmacol Ther ; 35(9): 1027-35, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22449251

RESUMO

BACKGROUND: Combination antiviral therapy holds the promise of increasing response rates while decreasing antiviral resistance, but has yet to be shown to be beneficial or necessary in chronic hepatitis B. AIM: To evaluate the benefit of combination therapy with adefovir and lamivudine versus adefovir alone in maintaining virological, biochemical and histological responses. METHODS: Patients with chronic hepatitis B with and without previous lamivudine therapy were randomised to receive adefovir alone (10 mg/daily) or adefovir and lamivudine (100 mg/daily) for up to 192 weeks. Study endpoints were (i) maintained virological (HBV DNA <500 copies/mL), biochemical and histological response, (ii) loss of HBeAg and (iii) loss of HBsAg. RESULTS: A total of 41 patients were enrolled, including 31 HBeAg -positive and 31 treatment-naïve subjects. 30 patients remained on assigned therapy at 192 weeks. The percentage of patients achieving a combined maintained response was higher in the combination than the monotherapy arm, both at week 48 (59% vs. 26%, P = 0.06) and 192 (68% vs. 31%, P = 0.03). At week 192, 76% of the combination vs. 36% of the monotherapy group had loss of HBeAg (P = 0.03). One patient receiving adefovir cleared HBsAg. Adefovir resistance developed in 6 of 19 (32%) monotherapy but none of 22 combination treated patients (P = 0.03). CONCLUSIONS: Extended combination therapy with lamivudine and adefovir is associated with a high rate of long-term virological and biochemical response. Adefovir monotherapy appears to be less effective mainly because of poor initial response and the ultimate development of antiviral resistance (www.Clinical. Trials.gov NCT00023309).


Assuntos
Adenina/análogos & derivados , Antivirais/uso terapêutico , Lamivudina/uso terapêutico , Organofosfonatos/uso terapêutico , Adenina/administração & dosagem , Adenina/uso terapêutico , Adulto , Antivirais/administração & dosagem , Farmacorresistência Viral , Quimioterapia Combinada , Feminino , Antígenos de Superfície da Hepatite B/análise , Antígenos E da Hepatite B/análise , Hepatite B Crônica/tratamento farmacológico , Humanos , Lamivudina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Organofosfonatos/administração & dosagem , Resultado do Tratamento
12.
Aliment Pharmacol Ther ; 33(5): 559-65, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21198704

RESUMO

BACKGROUND: Acute hepatitis C has variable modes of presentation and frequently results in chronic infection. Its optimal management has yet to be defined. AIM: To establish natural history and complications of treatment of acute hepatitis C. METHODS: Data from all patients presenting with acute hepatitis C to the National Institutes of Health between 1994 and 2007 were reviewed. RESULTS: Twenty-five patients were identified. Symptoms were reported by 80% and jaundice by 40%. Aminotransferase levels and hepatitis C virus (HCV) RNA levels fluctuated greatly; 18% of patients were intermittently negative for HCV RNA. Five patients recovered spontaneously whereas 20 developed chronicity or received interferon-based therapy during the acute phase. Among 15 patients treated during the acute phase with peginterferon with or without ribavirin for 24 weeks, all became HCV RNA negative within 4-8 weeks, and all except two (HIV-positive) achieved a sustained virological response. Side effects (particularly psychiatric) were common and limited treatment in 30%. CONCLUSIONS: Among 25 patients with acute HCV infection, fluctuating illness was common and spontaneous recovery occurred in only 20%. Anti-viral treatment with a 24-week course of peginterferon and ribavirin was highly effective, but marked by frequent and severe side effects.


Assuntos
Antivirais/efeitos adversos , Hepatite C/diagnóstico , Hepatite C/tratamento farmacológico , Interferon-alfa/efeitos adversos , Ribavirina/efeitos adversos , Doença Aguda , Adulto , Idoso , Progressão da Doença , Quimioterapia Combinada , Feminino , Hepatite C/fisiopatologia , Humanos , Interferon alfa-2 , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
13.
Aliment Pharmacol Ther ; 31(9): 1018-27, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20163377

RESUMO

BACKGROUND: Chronic infection with hepatitis C, genotype 2/3, responds better than other genotypes to peginterferon and ribavirin treatment. We hypothesized that a lower dose of peginterferon would be as effective, but less toxic than standard doses. AIM: To test the hypothesis that a lower dose of peginterferon would be as effective as, but less toxic than, standard doses. METHODS: A total of 30 patients were treated with low-dose peginterferon alfa-2a (90 microg/week) and 27 patients with standard doses (180 microg/week) for 24 weeks in combination with 800 mg/day of ribavirin. Patients who failed treatment were offered 48 weeks of standard-dose treatment. Viral and serum inducible protein 10 (IP-10) levels were measured and early viral kinetic parameters were calculated. RESULTS: Sustained virological response was achieved in 68% of the low-dose and 87% of the standard-dose patients (per protocol, P = 0.79 for non-inferiority). Re-treatment was successful in all patients who tolerated full dose and duration. The standard-dose group had greater first-phase declines of viral levels and faster time to negativity. The second-phase slope was not dose-dependent. IP-10 induction was significantly greater with the standard dose. Although fatigue and general feeling during treatment were worse for standard dose, haematological toxicity and depression did not differ between groups. CONCLUSION: A lower dose of peginterferon is associated with some symptomatic benefit, but the response is not equivalent to standard dosing.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/administração & dosagem , Polietilenoglicóis/administração & dosagem , Ribavirina/administração & dosagem , Adulto , Idoso , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Feminino , Genótipo , Humanos , Interferon alfa-2 , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo , Proteínas Recombinantes , Resultado do Tratamento
14.
Radiat Prot Dosimetry ; 136(3): 216-21, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19770213

RESUMO

The Chinese government initiated a conceptual design for the project of China Spallation Neutron Source (CSNS), which consists of an H-linear accelerator, a rapid cycling synchrotron accelerating the beam to 1.6 GeV, a target station converting proton beam into lower energy (<1 eV) neutron beam optimised to instruments for neutron scattering applications. The facility operates at 25-Hz repetition rate with an initial beam power of 100 kW. In the target station, the target-moderator-reflector (TMR) components are exposed to the intensive fluxes of high-energy hadrons and become highly radioactive as a result of long-time irradiation. In this paper, the activity of the TMR components are calculated using the Monte Carlo code system LAHET&MCNP4C&CINDER'90. Comparisons of some results with that simulated by FLUKA code are also performed. Detailed analyses of the radionuclides and their characters in the tantalum clad tungsten target (W-Ta target) are important for the radiation protection of the CSNS target station. The shielding design of the service cell for the decay gamma ray induced from the W-Ta target and its vessel shows that the ambient dose rate decreases exponentially with increasing heavy concrete thickness. And 80 cm thickness of heavy concrete for each side of the service cell can satisfy the safety requirement.


Assuntos
Modelos Teóricos , Aceleradores de Partículas/instrumentação , Lesões por Radiação/prevenção & controle , Proteção Radiológica/instrumentação , Proteção Radiológica/métodos , Radiometria/métodos , China , Simulação por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Doses de Radiação
15.
Genes Immun ; 10(4): 365-72, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19387461

RESUMO

Chronic hepatitis C virus (HCV) infection affects nearly 170 million individuals worldwide. Treatment of HCV with pegylated interferon-alpha-2a is successful in eradicating virus from only 30 to 80% of those treated. Interleukin-6 (IL-6) is an important cytokine involved in the immune response to infectious agents and in vitro studies suggest that host genetic variation, particularly haplotypes, may affect IL-6 expression. We examined the contribution of haplotypes in the IL-6 gene on sustained viral response (SVR) to the therapy for chronic HCV infection. We observed the IL-6 T-T-G-G-G-G-C-A-G-A haplotype to be associated with a lower risk of achieving SVR among Caucasian Americans (CAs) ((relative risk) RR=0.80; 95% CI: 0.66-0.98; P=0.0261). Using a sliding window approach, the rs1800797-(G)-rs1800796-(G)-rs1800795-(G) haplotype was associated with a reduced chance of SVR (RR=0.79; 95% CI: 0.66-0.94; P=0.0081), as was the rs1800796-(G)-rs1800795-(G)-rs2069830-(C) haplotype (RR=0.78; 95% CI: 0.66-0.94; P=0.0065) among CAs. Overall, the rs1800797-(G)-rs1800796-(G)-rs1800795-(G) haplotype was independently associated with a reduced chance of SVR (RR=0.78; 95% CI: 0.62-1.0; P=0.0489) after adjustment for potential confounding factors. Our findings further illustrate the complexity of IL-6 genetic regulation and the potential importance of haplotypes on IL-6 expression. Our findings provide additional support for the potential importance of genetic variation in the IL-6 gene and the response to HCV therapy.


Assuntos
Haplótipos/genética , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/genética , Interleucina-6/genética , Adulto , Alelos , Estudos de Coortes , Feminino , Regulação da Expressão Gênica , Frequência do Gene , Genótipo , Hepacivirus/efeitos dos fármacos , Humanos , Interferon alfa-2 , Interferon-alfa/uso terapêutico , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Polietilenoglicóis/uso terapêutico , Polimorfismo de Nucleotídeo Único/genética , Proteínas Recombinantes
16.
Aliment Pharmacol Ther ; 29(2): 172-82, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18945255

RESUMO

BACKGROUND: Non-alcoholic steatohepatitis (NASH) is a form of progressive fatty liver disease that is strongly associated with insulin resistance, which suggests that insulin sensitizing agents such as metformin may be beneficial for NASH. AIM: To assess the effects of metformin on insulin sensitivity, body composition, serum alanine aminotransferase (ALT) levels and liver histology in patients with NASH. METHODS: Patients underwent liver biopsy, metabolic profiling and imaging studies before and at the end 48 weeks of metformin (2000 mg/day) therapy. The primary endpoint was a three-point improvement in the histological NASH activity index. RESULTS: Of 28 patients enrolled, 26 (13 females; average age 44 years) completed 48 weeks of treatment and underwent repeat metabolic studies, imaging and liver biopsy. Thirty per cent achieved a histological response. Most patients lost weight, the average being 6 kg. There was a marked association between weight loss and improvements in NASH activity index and ALT levels (both, P < 0.01). Insulin sensitivity also improved, but the degree of change did not correlate with histological improvement. CONCLUSION: Metformin leads to improvements in liver histology and ALT levels in 30% of patients with NASH, probably by its effects in causing weight loss.


Assuntos
Fígado Gorduroso/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Fígado/efeitos dos fármacos , Metformina/uso terapêutico , Adulto , Biópsia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estatística como Assunto , Resultado do Tratamento
17.
Genes Immun ; 9(4): 328-33, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18418397

RESUMO

The human major histocompatability complex (MHC) genes encode the human leukocyte antigens, which are important in antigen presentation and regulation of CD8+ and CD4+ T cells. Response to therapies in hepatitis C virus (HCV) infection is highly variable (30-80%) and lower response rates have been reported among African Americans (AA; approximately 30%) compared to Caucasian Americans (CA; approximately 50%) infected with genotype-1 viruses. We evaluated whether MHC gene variants were associated with response to therapy and racial differences in AA and CA sustained virologic response (SVR) rates. We genotyped alleles at 8 MHC loci: 3 class I (A, B and C) and 5 class II (DRB1, DQA1, DQB1, DPA1 and DPB1) loci in 373 individuals (179 AA and 194 CA) with genotype-1 HCV infections, who were treated with peginterferon-alpha-2a and ribavirin. We observed carriage of A(*)02 (RR=1.33(1.08-1.64); P=0.008), B(*)58 (RR=1.84(1.24-2.73); P=0.002) and DPB1(*)1701 (RR=1.57(1.09-2.26); P=0.015) to be associated with SVR after adjustment for other predictors of response. In analysis of AA and CA subgroups separately, we observed potential, though not statistically significant, differences in these MHC associations. Variation in the immunogenetic background of HCV-infected individuals might account for some observed variation in viral-specific immunity and courses of disease. In this regard, future studies examining broader patient populations are warranted.


Assuntos
Antivirais/uso terapêutico , Genes MHC da Classe II , Genes MHC Classe I , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Negro ou Afro-Americano , Alelos , Estudos de Coortes , Quimioterapia Combinada , Feminino , Seguimentos , Genótipo , Hepatite C Crônica/etnologia , Hepatite C Crônica/virologia , Heterozigoto , Humanos , Interferon alfa-2 , Interferon-alfa/administração & dosagem , Masculino , Polietilenoglicóis/administração & dosagem , RNA Viral/genética , Proteínas Recombinantes , Ribavirina/administração & dosagem , Fatores de Tempo , Resultado do Tratamento , Estados Unidos , Carga Viral , População Branca
18.
Oral Dis ; 14(1): 10-4, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18173443

RESUMO

Hepatitis C is a major cause of chronic liver disease. It has been recognized as a global health problem because of the progression to cirrhosis and hepatocellular cancer. Chronic hepatitis C is usually asymptomatic but can cause considerable liver damage before its recognition. This review discusses the natural history, clinical features, diagnosis, therapy, treatment responses and the side effects associated with the treatment of hepatitis C.


Assuntos
Hepatite C Crônica , Antivirais/uso terapêutico , Diagnóstico Diferencial , Progressão da Doença , Hepatite C/tratamento farmacológico , Anticorpos Anti-Hepatite C/sangue , Hepatite C Crônica/diagnóstico , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/fisiopatologia , Humanos
19.
Phys Rev E Stat Nonlin Soft Matter Phys ; 69(2 Pt 2): 026414, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14995573

RESUMO

We investigate the angular distribution and the energy spectrum of hot electrons emitted from ethanol droplets irradiated by linearly polarized 150-fs laser pulses at an intensity of 10(16) W/cm(2). Two hot electron jets symmetrically with respect to the laser propagation direction are observed within the polarization plane. This is due to the spherical geometry of droplets in the intense laser field. The maximum energy of the hot electrons is found to be more than 600 keV. Particle-in-cell simulations suggest that the resonance absorption is the main mechanism for hot electron generation.

20.
Phys Rev Lett ; 90(16): 165002, 2003 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-12731980

RESUMO

High energy electrons emitted by water plasmas produced by a single or a multiple laser pulse are investigated. The multipulse mode greatly enhances the generation and the temperature of hot electrons. Directional emission of high energy electrons over 25 keV is observed in two symmetric directions with respect to the laser axis and at 46 degrees from the directions of the laser electric field. Two-dimensional particle-in-cell simulations reproduce well the experimental results and indicate that the acceleration mechanism of the high energy electrons is due mainly to the resonance absorption at the edge of the spherical droplets formed by the leading pulse.

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