AIM: To construct a non-resistant and attenuated Salmonella typhimurium ( S. typhimurium) strain which expresses conservative region of adhesion AB of Helicobacter pylori(Hpylon) and evaluate its immunogenicity.METHOD...AIM: To construct a non-resistant and attenuated Salmonella typhimurium ( S. typhimurium) strain which expresses conservative region of adhesion AB of Helicobacter pylori(Hpylon) and evaluate its immunogenicity.METHODS: The AB gene amplified by PCR was inserted into the expression vector pYA248 containing asd gene and through two transformations introduced into the delta Cya1 delta Crp1 delta Asd attenuated Salmonella typhimurium strain, constructing balanced lethal attenuated Salmonella typhimurium strains X4072 (pYA248-AB). Bridged ELISA method was used to measure the expression of AB antigen in sonicate and culture supematant. According to the method described by Meacock, stability of the recombinant was evaluated. Semi-lethal capacity test was used to evaluate the safety of recombinant. The immunogenicity of recombinant was evaluated with animal experiments.RESULTS: The attenuated S. typhimurium X4072 (pYA248-AB) which expresses AB was successfully constructed.Furthermore, bridged ELISA assay showed that the content of AB in recombinant X4072 (pYA248- AB) culture supematant was higher than that was in thallus lytic liquor. And after recombinant X4072 (pYA248- AB) was cultured for 100 generations without selection pressure, bhe entire recombinant bacteria selected randomly could grow, and the AB antigen was defected positive by ELISA. The growth curve of the recombinant bacteria showed that the growth states of X4072 (pYA248) and X4072 (pYA248-AB) were basically consistent. The survival rate of C57BL/6 was still 100%, at 30 d after mice taking X4072 (pYA248-AB) 1.0×l0^10 cfu orally. Oral immunization of mice with X4072 (pYA248-AB) induced a specific immune response.CONCLUSION: In vitro recombinant plasmid appears to be stable and experiments on animals showed that the recombinant strains were safe and immunogenic in vitro,which providing a new live oral vaccine candidate for protection and care of H pylori infection.展开更多
The management of Meckel diverticulum found un-expectedly during an abdominal operation remains controversial. Most published reports have included only patients undergoing diverticulectomy or bowel resection through ...The management of Meckel diverticulum found un-expectedly during an abdominal operation remains controversial. Most published reports have included only patients undergoing diverticulectomy or bowel resection through laparotomy. We report a case of a carcinoid tumor in a Meckel’s diverticulum which was incidentally detected and removed during laparoscopic inguinal hernia repair. Although there is no compelling evidence in the literature to recommend prophylactic diverticulectomy, laparoscopic stapled resection repre-sents a viable and safe approach in healthy individuals undergoing elective surgery for other purposes.展开更多
AIM. To assess the causes of ileocecal mass in patients with amebic liver abscess. METHODS： Patients with amebic liver abscess and ileocecal mass were carefully examined and investigated by contrast-enhanced CT scan ...AIM. To assess the causes of ileocecal mass in patients with amebic liver abscess. METHODS： Patients with amebic liver abscess and ileocecal mass were carefully examined and investigated by contrast-enhanced CT scan followed by colonoscopy and histological examination of biopsy materials from lesions during colonoscopy. RESULTS： Ileocecal masses were found in seventeen patients with amebic liver abscess. The cause of the mass was ameboma in 14 patients, cecal tuberculosis in 2 patients and adenocarcinoma of the cecum in 1 patient. Colonic ulcers were noted in five of the six （83%） patients with active diarrhea at presentation. The ileocecal mass in all these patients was ameboma. Ulcers were seen in only one of the 11 （9%） patients without diarrhea. The difference was statistically significant from the group with diarrhea （P〈 0.005）. CONCLUSION： Ileocecal mass is not an uncommon finding in patients with amebic liver abscess. Although, the ileocecal mass is due to ameboma formation in most cases, it should not be assumed that this is the case in all patients. Colonoscopy and histological examination of the target biopsies are mandatory to avoid missing a more sinister lesion.展开更多
基金Supported by the National Natural Science Foundation of China,No.30270078
文摘AIM: To construct a non-resistant and attenuated Salmonella typhimurium ( S. typhimurium) strain which expresses conservative region of adhesion AB of Helicobacter pylori(Hpylon) and evaluate its immunogenicity.METHODS: The AB gene amplified by PCR was inserted into the expression vector pYA248 containing asd gene and through two transformations introduced into the delta Cya1 delta Crp1 delta Asd attenuated Salmonella typhimurium strain, constructing balanced lethal attenuated Salmonella typhimurium strains X4072 (pYA248-AB). Bridged ELISA method was used to measure the expression of AB antigen in sonicate and culture supematant. According to the method described by Meacock, stability of the recombinant was evaluated. Semi-lethal capacity test was used to evaluate the safety of recombinant. The immunogenicity of recombinant was evaluated with animal experiments.RESULTS: The attenuated S. typhimurium X4072 (pYA248-AB) which expresses AB was successfully constructed.Furthermore, bridged ELISA assay showed that the content of AB in recombinant X4072 (pYA248- AB) culture supematant was higher than that was in thallus lytic liquor. And after recombinant X4072 (pYA248- AB) was cultured for 100 generations without selection pressure, bhe entire recombinant bacteria selected randomly could grow, and the AB antigen was defected positive by ELISA. The growth curve of the recombinant bacteria showed that the growth states of X4072 (pYA248) and X4072 (pYA248-AB) were basically consistent. The survival rate of C57BL/6 was still 100%, at 30 d after mice taking X4072 (pYA248-AB) 1.0×l0^10 cfu orally. Oral immunization of mice with X4072 (pYA248-AB) induced a specific immune response.CONCLUSION: In vitro recombinant plasmid appears to be stable and experiments on animals showed that the recombinant strains were safe and immunogenic in vitro,which providing a new live oral vaccine candidate for protection and care of H pylori infection.
文摘The management of Meckel diverticulum found un-expectedly during an abdominal operation remains controversial. Most published reports have included only patients undergoing diverticulectomy or bowel resection through laparotomy. We report a case of a carcinoid tumor in a Meckel’s diverticulum which was incidentally detected and removed during laparoscopic inguinal hernia repair. Although there is no compelling evidence in the literature to recommend prophylactic diverticulectomy, laparoscopic stapled resection repre-sents a viable and safe approach in healthy individuals undergoing elective surgery for other purposes.
文摘AIM. To assess the causes of ileocecal mass in patients with amebic liver abscess. METHODS： Patients with amebic liver abscess and ileocecal mass were carefully examined and investigated by contrast-enhanced CT scan followed by colonoscopy and histological examination of biopsy materials from lesions during colonoscopy. RESULTS： Ileocecal masses were found in seventeen patients with amebic liver abscess. The cause of the mass was ameboma in 14 patients, cecal tuberculosis in 2 patients and adenocarcinoma of the cecum in 1 patient. Colonic ulcers were noted in five of the six （83%） patients with active diarrhea at presentation. The ileocecal mass in all these patients was ameboma. Ulcers were seen in only one of the 11 （9%） patients without diarrhea. The difference was statistically significant from the group with diarrhea （P〈 0.005）. CONCLUSION： Ileocecal mass is not an uncommon finding in patients with amebic liver abscess. Although, the ileocecal mass is due to ameboma formation in most cases, it should not be assumed that this is the case in all patients. Colonoscopy and histological examination of the target biopsies are mandatory to avoid missing a more sinister lesion.
