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1.
J Viral Hepat ; 20(7): 494-501, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23730843

RESUMO

Mutations within the coding region of hepatitis B surface antigen (HBsAg) have been found naturally in chronic carriers. To characterize the mutations of HBsAg from Iranian chronic carriers who were vaccine and/or medication naive. The surface genes from 360 patients were amplified and directly sequenced. The distribution of amino acid substitutions was classified according to different immune epitopes of the surface protein. All isolates belonged to genotype D. 222 (61.6%) of 360 patients contained at least one amino acid substitution. 404 (74.5%) of 542 amino acid changes occurred in different immune epitopes of HBsAg, of which 112 (27.7%) in 32 residues of B-cell epitopes (62 in the 'a' determinant); 111 (27.4%) in 32 residues of T helper; and 197 (48.7%) in 32 residues inside cytotoxic T lymphocyte (CTL) epitopes. One Th (186-197) and two CTL (28-51 and 206-215) epitopes were found to be hotspot motifs for the occurrence of 213 (52.7%) substitutions. 20 stop codons were identified in different epitopes. There was a significant association between amino acid substitutions and anti-HBe seropositivity; however, the correlation between such changes with viral load and ALT levels was not significant. In chronic hepatitis B virus(HBV) carriers, positive selection in particular outside the 'a' determinant appeared to exert influence on the surface proteins. These changes could be immune escape mutations naturally occurring due to the host immune surveillance especially at the T-cell level.


Assuntos
Portador Sadio/virologia , Epitopos de Linfócito T/genética , Antígenos de Superfície da Hepatite B/genética , Vírus da Hepatite B/genética , Hepatite B Crônica/virologia , Mutação de Sentido Incorreto , Adulto , Substituição de Aminoácidos , Estudos Transversais , DNA Viral/química , DNA Viral/genética , Epitopos de Linfócito T/imunologia , Feminino , Antígenos de Superfície da Hepatite B/imunologia , Vírus da Hepatite B/isolamento & purificação , Humanos , Evasão da Resposta Imune , Irã (Geográfico) , Masculino , Pessoa de Meia-Idade , Análise de Sequência de DNA , Linfócitos T Citotóxicos/imunologia
2.
Middle East J Dig Dis ; 3(1): 13-9, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25197527

RESUMO

Hepadnaviruses employ an unusual strategy for the production of enormous number of virions during replication which makes rapid and substantial genetic sequence changes and alterations. The pathogenesis and clearance of hepatitis B virus (HBV) infection are engaged by the selection and expression of viral mutants during virus-host interactions. Mutations in regulatory regions such as the basal core promoter (BCP) which is thought to be related to lower production of hepatitis B "e" antigen (HBeAg) directly affects the clinical presentation of liver disease. However, the molecular structure of these mutations in chronic carriers has not been adequately evaluated. In this review we evaluate the molecular aspect and pathologic basis of basal core promoter mutations.

3.
Int J Organ Transplant Med ; 1(4): 171-6, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-25013582

RESUMO

BACKGROUND: Ishak and METAVIR scoring systems are among the most commonly used histopathological systems to evaluate chronic hepatitis. OBJECTIVE: To assess the level of agreement between these two scoring systems in patients with chronic hepatitis B. METHODS: Liver biopsy samples taken from 92 patients with chronic hepatitis B were considered as the training set; 57 more biopsy specimens were used as the validation set. In the training set, grade of necroinflammation and stage of fibrosis for each liver biopsy specimen were determined by two expert liver pathologists using both Ishak and METAVIR systems. Inter-observer variability between the two pathologists was evaluated. Biopsy specimens of the validation set were seen and scored by a third expert pathologist. In the training set, criteria were developed to categorize Ishak grading and staging systems separately to best fit with the METAVIR scoring system. The criteria found in the training set, was then tested in the validation set. The level of agreement between the two scoring systems was assessed by weighted kappa statistics. RESULTS: For the training set, agreement between the two pathologists was excellent. Using our proposed criteria in the training set, there was excellent level of agreement in grading (κ = 0.89) and staging (κ = 0.99) between Ishak and METAVIR systems. In the validation set, the criteria led to substantial correlation (κ = 0.61) in grading, and excellent correlation (κ = 0.94) in staging between the two systems. CONCLUSION: Using our proposed criteria, excellent or at least substantial concordance between Ishak and METAVIR scoring systems can be achieved for the degree of both necro-inflammatory changes and fibrosis.

4.
J Viral Hepat ; 15(10): 753-60, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18507754

RESUMO

SUMMARY: The impact of mutations in the precore and basal core promoter (BCP) regions of the hepatitis B virus on the course of chronic liver disease is not well established. We sought to examine the relationship of these characteristics to the clinical expression of liver disease in patients infected with genotype D chronic hepatitis B (CHB). BCP and precore mutations in 110 patients with genotype D1 CHB were determined and correlated with clinical phenotype. Of 110 patients, 95 (86.5%) were HBeAg-negative. Compared with HBeAg-positive subjects, HBeAg-negative patients were over a decade older and had lower viral loads (3.70 +/- 0.98 vs 5.77 +/- 0.69 log copies/ml, P < 0.001). The double mutation A1762T-G1764A was more prevalent in patients with advanced liver disease (AdLD) and was associated with higher alanine aminotransferase and viral load. After adjusting for age, there was a more than fourfold increase in the risk of AdLD with this mutation (OR = 4.4; 95% CI: 1.13-16.92, P < 0.03). Conversely, the G1757A substitution was associated with protection, being 90% less frequent among patients with AdLD (P = 0.001). The results indicate that in genotype D CHB, the presence of the A1762T-G1764A mutation was associated with more aggressive liver disease while the G1757A substitution was associated with protection from advanced disease.


Assuntos
Vírus da Hepatite B , Hepatite B Crônica , Mutação , Regiões Promotoras Genéticas/genética , Precursores de Proteínas/genética , Proteínas do Core Viral/genética , Adulto , Idoso , DNA Viral/análise , DNA Viral/isolamento & purificação , Feminino , Genótipo , Antígenos do Núcleo do Vírus da Hepatite B/genética , Vírus da Hepatite B/classificação , Vírus da Hepatite B/genética , Vírus da Hepatite B/patogenicidade , Hepatite B Crônica/genética , Hepatite B Crônica/fisiopatologia , Hepatite B Crônica/virologia , Humanos , Irã (Geográfico) , Masculino , Pessoa de Meia-Idade , Filogenia
5.
Aliment Pharmacol Ther ; 24(6): 983-9, 2006 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-16948810

RESUMO

BACKGROUND: Pneumatic dilatation is the first line therapy in achalasia, but half of patients relapse within 5 years of therapy and require further dilatations. AIM: To assess whether botulinum toxin injection before pneumatic dilatation is superior to pneumatic dilatation alone in achalasia patients. METHODS: Newly diagnosed achalasia patients were randomly assigned to receive botulinum toxin 1 month before pneumatic dilatation (botulinum toxin-pneumatic dilatation group: 27 patients with median age of 38) or to undergo pneumatic dilatation alone (pneumatic dilatation group: 27 patients with median age of 30). Response to therapy was assessed by clinical and objective methods at various intervals. RESULTS: One-year remission rate of patients in botulinum toxin-pneumatic dilatation group was 77% compared with 62% in pneumatic dilatation group (P = 0.1). In pneumatic dilatation group, the oesophageal barium volume significantly (P < 0.001) decreased at 1 month, but this reduction did not persist over 1-year follow-up. Botulinum toxin-pneumatic dilatation group showed a significant (P < 0.001) reduction in barium volume at the various times intervals post-treatment. In the botulinum toxin-pneumatic dilatation group, 10/11 (91%) patients over 40 were in remission at 1 year, comparing with only five of nine (55%) cases in pneumatic dilatation group (P = 0.07). CONCLUSION: Injection of botulinum toxin before pneumatic dilatation does not significantly enhance the efficacy of pneumatic dilatation.


Assuntos
Antidiscinéticos/administração & dosagem , Toxinas Botulínicas/administração & dosagem , Cateterismo/métodos , Acalasia Esofágica/terapia , Adulto , Fatores Etários , Antidiscinéticos/efeitos adversos , Bário/análise , Toxinas Botulínicas/efeitos adversos , Cateterismo/efeitos adversos , Acalasia Esofágica/fisiopatologia , Esfíncter Esofágico Inferior/efeitos dos fármacos , Esfíncter Esofágico Inferior/fisiopatologia , Esôfago/química , Esôfago/fisiopatologia , Feminino , Humanos , Injeções , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Recidiva , Resultado do Tratamento
6.
Aliment Pharmacol Ther ; 22(3): 261-5, 2005 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-16091064

RESUMO

BACKGROUND: The non-invasive assessment of primary achalasia is not precise. AIM: To compare investigations before and 1 month after balloon dilation in achalasia. METHODS: Fifty-two patients with primary achalasia were enrolled. Subjective and objective variables of oesophageal functions were analysed before and 1 month after balloon dilation. RESULTS: The mean predilation symptom score, lower oesophageal sphincter pressure, height and volume of barium at 5 min were 7.7 +/- 2.6, 62.0 +/- 25.1 mmHg, 9.2 +/- 6.1 cm and 53.2 +/- 49.8 mL respectively; the mean postdilation values were 3.0 +/- 3.0, 34.1 +/- 12.5 mmHg, 7.9 +/- 5.1 cm and 28.0 +/- 30.1 mL respectively. The before dilation volume of barium at 5 min correlates significantly with lower oesophageal sphincter pressure (P < 0.01). The mean symptom scores, lower oesophageal sphincter pressure and volume of barium at 5 min dropped significantly after intervention (P < 0.01), but the reduction in barium height at 5 min was not significant. The percentage changes in volume at 5 min significantly predicted the percentage changes in lower oesophageal sphincter pressure (P < 0.01). CONCLUSIONS: The volume of barium retention at 5 min can predict the lower oesophageal sphincter pressure before and after balloon dilation in primary achalasia. This could be used as a non-invasive objective tool for initial and post-dilation assessment.


Assuntos
Acalasia Esofágica/diagnóstico , Acalasia Esofágica/terapia , Esfíncter Esofágico Inferior/fisiopatologia , Adulto , Sulfato de Bário , Cateterismo , Meios de Contraste , Acalasia Esofágica/diagnóstico por imagem , Feminino , Humanos , Masculino , Manometria , Pessoa de Meia-Idade , Variações Dependentes do Observador , Pressão , Radiografia , Resultado do Tratamento
7.
Dis Esophagus ; 17(3): 213-7, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15361093

RESUMO

Graded pneumatic dilatation (PD) is an appropriate long-term therapy and botulinum toxin injection (BT) is a relatively short-term therapy in idiopathic achalasia. Their combination has not been previously scrutinized. This study aimed to evaluate the role of BT in enhancing the efficacy of PD with 30 mm balloons. Patients who underwent PD with 30 mm balloons after botulinum toxin injections and a group of age- and sex-matched controls who were treated only with PD were enrolled in the study. Symptom scores were taken before, 1 month after and then every 3 months after PD. There were no significant differences between the two groups in gender, duration or severity of symptoms. One of the 12 patients in the case group relapsed 30 months after PD but the others were in remission for an average of 25.6 months. In the control group, all the patients relapsed after a mean of 12.6 months and needed a 35-mm PD. The cumulative remission rate was significantly higher in the case group compared with the control group (P < 0.01). The mean symptom score decreased by 76% in the case group (P < 0.001) and 53% in the controls (P < 0.01) at the end of the first month. Neither age, sex, nor duration or severity of symptoms were predictive of patients' responses to treatment. It seems that BT may be a meaningful enhancing factor in long-term efficacy of PD. PD with a 30 mm balloon after a BT session may resolve the need for the future higher grade PD.


Assuntos
Toxinas Botulínicas Tipo A/uso terapêutico , Cateterismo , Acalasia Esofágica/terapia , Fármacos Neuromusculares/uso terapêutico , Adolescente , Adulto , Idoso , Criança , Terapia Combinada , Feminino , Humanos , Injeções , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Recidiva , Fatores de Tempo , Resultado do Tratamento
8.
Aliment Pharmacol Ther ; 20(4): 431-6, 2004 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-15298637

RESUMO

BACKGROUND: Pneumatic dilatation is considered to be the first line therapy for achalasia, but long-term outcome studies are scarce and limited by their retrospective design. There is also no consensus on the optimal method for performing pneumatic dilation as regard to balloon diameter, amount and the rate inflation pressure. AIM: To address these questions in a large long-term prospective study. METHODS: Over a period of 10 years 262 achalasia patients referred to our centre were enrolled. All patients underwent a pre-treatment clinical evaluation and were followed every 6 months. The first 62 patients (group A) underwent dilatation with initial use of a 35 mm balloon with inflation pressure of 10 psi in 10 seconds (s). In group B (200 patients) we initially used a 30 mm balloon with inflation pressure of 10 psi in 30 s. Dilatation was repeated with incrementally larger balloons (35 and 40 mm) in case of relapse. We used rigiflex balloon and maintained pressure for 60 s after inflation in both groups. RESULTS: Three perforations occurred in group A whereas no perforation took place in Group B. The cumulative proportional remission rate with single dilatation in groups A and B decreased from 83 and 75% in 6 months to 60 and 57% after 30 months of therapy respectively, the differences did not reach statistical significance. In patients who had undergone further dilatations the probability of remaining in remission at 1 year after the first and the second dilatation was 38 and 88% in group A, 20 and 89% in group B respectively. The probability of remaining in remission for 2 years increased from 20% after the first dilatation to 70% after the second dilatation. CONCLUSION: Graded pneumatic balloon dilatation with 30 mm diameter and slower rate of balloon inflation is an effective and safe initial method of therapy for achalasia. The duration of remission can be extended by repeated dilatation with larger size balloon.


Assuntos
Cateterismo/métodos , Acalasia Esofágica/terapia , Adulto , Cateterismo/efeitos adversos , Cateterismo/instrumentação , Desenho de Equipamento , Feminino , Humanos , Masculino , Estudos Prospectivos , Indução de Remissão , Prevenção Secundária , Resultado do Tratamento
9.
Aliment Pharmacol Ther ; 15(9): 1389-96, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11552910

RESUMO

BACKGROUND: Therapeutic options for achalasia include pharmacological therapy, surgical myotomy, pneumatic dilatation and intrasphincteric botulinum toxin injection. AIM: To compare botulinum toxin injection with pneumatic dilatation in a randomized trial. PATIENTS/METHODS: Forty adults with newly diagnosed achalasia were randomized to receive botulinum toxin (n=20) or pneumatic dilatation (n=20). Symptom scores were evaluated at 1, 6 and 12 months. Clinical relapse was defined as a symptom score greater than 50% of baseline. Relapsers received a second botulinum toxin injection or pneumatic dilatation. RESULTS: The cumulative 12-month remission rate was significantly higher after a single pneumatic dilatation (53%) compared to a single botulinum toxin injection (15%)(P < 0.01). The 12-month estimated adjusted hazard for relapse and need for retreatment for the botulinum toxin group was 2.69 times that of the pneumatic dilatation group (95% confidence interval; 1.18-6.14). When a second treatment was administered to the relapsers in each group, the cumulative remission rate 1 year after initial treatment was significantly higher in the pneumatic dilatation group (100%) compared to the botulinum toxin group (60%) (P < 0.01). There were no major complications in either group. CONCLUSIONS: Pneumatic dilatation is more efficacious than botulinum toxin in providing sustained symptomatic relief in patients with achalasia. The efficacy of a single pneumatic dilatation is similar to that of two botulinum toxin injections.


Assuntos
Toxinas Botulínicas/uso terapêutico , Cateterismo/métodos , Acalasia Esofágica/terapia , Acalasia Esofágica/tratamento farmacológico , Feminino , Humanos , Masculino , Manometria , Pessoa de Meia-Idade , Resultado do Tratamento
11.
J Immunol ; 122(3): 1087-90, 1979 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-376702

RESUMO

Purified peripheral blood T lymphocytes from normal donors were shown to help allogeneic tonsillar B cells to differentiate and secrete specific anti-SRBC antibody in vitro in a plaque-forming assay. Utilizing this system, a comparison was made between the allogeneic helper activity generated by the T cells of normal individuals and patients with various disease states. Allogeneic helper activity was absent when T lymphocytes from patients with CLL were used. Conversely, relatively normal allogeneic helper function was provided by T cells of patients with a variety of other disorders studied. Thus, a functional deficiency was identified in CLL patients in the subpopulation of regulatory T cells responsible for providing helper activity in allogeneic interactions.


Assuntos
Leucemia Linfoide/imunologia , Linfócitos T/imunologia , Linfócitos B/imunologia , Sítios de Ligação de Anticorpos , Classificação , Técnica de Placa Hemolítica , Humanos , Fragmentos Fc das Imunoglobulinas , Imunoglobulina M , Ativação Linfocitária , Formação de Roseta
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