RESUMO
<p><b>OBJECTIVE</b>To clone Streptococcus salivarius (Ss) 57. I urease gene, which can express ureolytic activity in Escherichia coli (Ec) without adding extra nickel ions.</p><p><b>METHODS</b>Urease gene was cloned by polymerase chain reaction in three separate parts. The three separate plasmids were digested by specific restriction enzymes and ligated together. The expression of the complete urease gene in Ec was detected by phenol red assay and pH analysis.</p><p><b>RESULTS</b>Urease gene of Ss 57.I was eventually cloned and proved correct. Urease activity of the obtained clone was positive in Ec. Without adding extra NiCl(2), the recombinant Ec could hydrolyze urea to produce ammonia, resulting in the increase of pH value.</p><p><b>CONCLUSIONS</b>The clone of Ss urease gene obtained in this study could express ureolytic activity in Ec without adding extra nickel ions. The current clone can be used to construct ureolytic effector strain used in replacement therapy in caries prevention.</p>
Assuntos
Clonagem de Organismos , Cárie Dentária , Microbiologia , Escherichia coli , Genética , Concentração de Íons de Hidrogênio , Níquel , Química , Streptococcus , Genética , Urease , GenéticaRESUMO
<p><b>OBJECTIVE</b>To investigate gene mutations of epidermal growth factor receptor (EGFR) and K-ras in Chinese patients with non-small cell lung cancer (NSCLC) and its clinicopathological significance, and to analyze the correlation between these mutations and tumor response to erlotinib treatment.</p><p><b>METHODS</b>Mutations of exons 18, 19, 20 and 21 of the EGFR and codons 12, 13 of the K-ras in 301 cases of NSCLC were detected by PCR-amplification and gene sequencing. The relationship between the mutations and clinicopathological characteristics of the 301 patients was analyzed.</p><p><b>RESULTS</b>EGFR mutations were present in 32.9% (99/301) of the samples: 3 mutation in exon 18, 59 in exon 19, 2 in exon 20, and 35 in exon 21. Mutations of K-ras were present in 4.7% (14/301) of the samples: 13 in codon 12 and 1 in codon 13. EGFR mutations were never found in tumors with K-ras mutations, suggesting a mutually exclusive relationship. EGFR mutations were more common in adenocarcinomas, non-smokers and females. Seven out of 10 erlotinib-treated patients with disease control carried EGFR mutation.</p><p><b>CONCLUSION</b>The frequency of EGFR mutation in Chinese NSCLC patients is higher than that in Westerners, but the frequency of K-ras mutation is quite opposite. Combined detection of EGFR gene and K-ras gene mutation may help clinicians to choose patients who may gain benefit from EGFR tyrosine kinase inhibitor (EGFR-TKI) treatment, and to predict their response to erlotinib treatment and prognosis.</p>
Assuntos
Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Adenocarcinoma , Tratamento Farmacológico , Genética , Patologia , Povo Asiático , Carcinoma Pulmonar de Células não Pequenas , Tratamento Farmacológico , Genética , Patologia , Carcinoma de Células Escamosas , Tratamento Farmacológico , Genética , Patologia , Códon , Cloridrato de Erlotinib , Éxons , Genes erbB-1 , Genes ras , Neoplasias Pulmonares , Tratamento Farmacológico , Genética , Patologia , Mutação , Inibidores de Proteínas Quinases , Usos Terapêuticos , Proteínas Proto-Oncogênicas , Genética , Proteínas Proto-Oncogênicas p21(ras) , Quinazolinas , Usos Terapêuticos , Receptores ErbB , Genética , Fatores Sexuais , Fumar , Proteínas ras , GenéticaRESUMO
<p><b>OBJECTIVE</b>To construct the virus-like parcel expressing hepatitis B virus (HBV) C gene and identify its immunogenicity.</p><p><b>METHODS</b>HBV C gene was cloned into the shuttle vector pSC11, and the resulted plasmid pSC11-C was transfected into modified vaccinia virus Ankara (MVA).</p><p><b>RESULTS</b>pSC11-C was correctly constructed as verified by sequence analysis and PCR, and the recombinant virus-like parcel possessed good immunogenicity.</p><p><b>CONCLUSION</b>The MVA-C expressing HBV C gene has been successfully constructed to provide important basis for gene therapy research of chronic HBV infection.</p>
Assuntos
Genes Virais , Vetores Genéticos , Antígenos do Núcleo do Vírus da Hepatite B , Genética , Recombinação Genética , Vaccinia virus , GenéticaRESUMO
Objective To analyze spiral CT manifestations and the diagnostic value of pulmonary embolism (PE).Methods Spiral CT pulmonary angiography (SCTPA) and chest plain CT scan were performed in 25 cases with highly-suspected PE. CT findings were retrospectively analyzed.Results The direct signs of PE appeared as complete or partial filling defect within pulmonary arteriae on SCTPA.191 branches of pulmonary artery were involved in all cases,of them, 44 branches were centrally located(23.0%), 115 branches were eccentrically located (60.2%),7 branches were mural filling defect (3.7%), 25 branches were complete occlusion (13.1%).The indirect signs of PE included irregular consolidation (n=15), patchy ground glass opacities (n=6),local streak shadows(n=4),"mosaic"sign (n=5), pleural effusion(n=16) ,pericardial effusion (n=3)and simple emboli no other signs(n=3).Conclusion SCTPA is a fast ,effective, security and non-invasive diagnostic method for PE .