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The immunologic basis for protection against Brazilian purpuric fever, a septicemic infection associated with Haemophilus influenzae biogroup aegyptius bacteremia, is unknown. Passive immunization of infant rats with antiserum to whole bacterial cells of the homologous strain protects them from experimental bacteremia following bacterial challenge. In immunoblotting, antibody to a 145-kDa protein (P145) was present in protective antisera but not in nonprotective antisera. As judged by analysis of the antibodies eluted from whole bacterial cells and the agglutination of bacteria by antisera to P145, this protein is surface exposed. We prepared monospecific rat antisera to this protein by three methods: (i) immunization with whole bacterial cells and absorption with a Brazilian purpuric fever strain not expressing P145, (ii) immunization with gel-purified P145, and (iii) immunization with a P145-expressing transformant of a laboratory H. influenzae strain expressing this protein and absorption of the antiserum with the laboratory H. influenzae strain. These antisera had low antilipooligosaccharide antibody titers, were reactive only with P145, and had bactericidal activity in vitro. Following passive immunization, these antisera partially protected infant rats from bacteremia resulting from intraperitoneal challenge with bacteria. As assessed by immunoblotting, pooled adult human sera contained antibodies reactive with P145. Antibody to P145 may contribute to protection against Brazilian purpuric fever.  相似文献   
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Monoclonal antibodies (MAbs) were raised against Penicillium aurantiogriseum var. melanoconidium. Cross‐reactivity studies were carried out against 12 ‘field’ and 27 ‘storage’ fungi. Two MAbs (MAbs 32 and 37) reacted with all of the fungi tested and a third (MAb 38) with 38 out of the 39 fungi (although weakly with some). Monoclonal antibodies 32 and 37, but not MAb 38, were found to react to a degree with ‘clean’ barley. Enzyme‐linked immunosorbent assay (ELISA) using MAb 38 and extracts of barley inoculated with the homologous antigen showed a clear relationship between absorbance and amount of fungal growth. It is suggested that these MAbs could be used in a broad‐spectrum assay to detect fungi of significance to the quality of foods and feeds.  相似文献   
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Purpose: The urokinase plasminogen activator (uPA) and its receptor (uPAR) are expressed by pancreatic cancer cells and can be targeted by the plasminogen activator inhibitor type 2 (PAI2). We have labeled PAI2 with 213Bi to form the alpha conjugate (AC), and have studied its in vitro cytotoxicity and in vivo efficacy. Methods and Materials: The expression of uPA/uPAR on pancreatic cell lines, human pancreatic cancer tissues, lymph node metastases, and mouse xenografts were detected by immunohistochemistry, confocal microscopy, and flow cytometry. Cytotoxicity was assessed by the MTS and TUNEL assay. At 2 days post-cancer cell subcutaneous inoculation, mice were injected with AC by local or systemic injection. Results: uPA/uPAR is strongly expressed on pancreatic cancer cell lines and cancer tissues. The AC can target and kill cancer cells in vitro in a concentration-dependent fashion. Some 90% of TUNEL positive cells were found after incubation with 1.2 MBq/ml of AC. A single local injection of ~222 MBq/kg 2 days post-cell inoculation can completely inhibit tumor growth over 12 weeks, and an intraperitoneal injection of 111 MBq/kg causes significant tumor growth delay. Conclusions: 213Bi-PAI2 can specifically target pancreatic cancer cells in vitro and inhibit tumor growth in vivo. 213Bi-PAI2 may be a useful agent for the treatment of post-surgical pancreatic cancer patients with minimum residual disease.  相似文献   
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Acute rejection is a major determinant of chronic allograft dysfunction and graft survival. This study evaluated the effect of basiliximab (Simulect®), a 156-kDa chimeric monoclonal antibody (human and murine) directed against the alpha chain of the interleukin (IL)-2 receptor of human lymphocytes, on acute rejection in pediatric renal transplantation. Data were collected from two pediatric renal transplantation centers. Forty transplantations (22 males and 18 females; mean age 14.8±3.6 years) were performed between 1996 and 2001. Twelve of the grafts came from cadaveric donors and 28 from living-related donors. Twenty-four of the patients were on hemodialysis, 15 were on peritoneal dialysis, and one case was a pre-emptive transplantation. All patients were placed on triple-drug immunosuppression [prednisolone + (azathioprine or mycophenolate mofetil) +(cyclosporine or tacrolimus)]. Basiliximab was also administered in 17 cases. The respective rates of biopsy-proven acute rejection in the basiliximab group and the standard-regimen group were 0% vs. 17.4% ( P >0.05) at 1 month post-transplantation; 0% vs. 26.1% ( P <0.05) at 3 months; and 0% vs. 26.1% ( P <0.05) at 6 months. Thirty and 16 patients had completed 1- and 3-year follow ups, respectively, at the time of writing; the 1- and 3-year graft survival rates were 96% (29/30) and 81% (13/16), respectively.
Basiliximab significantly reduced the rates of acute rejection at 3- and 6 months post-pediatric renal transplantation. It was well tolerated by all patients, and caused no significant adverse effects. The effect of basiliximab on long-term graft survival and chronic allograft dysfunction deserves further investigation.  相似文献   
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Barrett esophagus (BE) is a condition in which the normal squamous epithelium of the esophagus is replaced by a metaplastic columnar epithelium. BE is a premalignant lesion that represents the initial step in a metaplasia-dysplasia-carcinoma sequence. In the present study, amplification of the proto-oncogene c-myc was determined by means of differential polymerase chain reaction analysis of metaplastic specialized epithelium, low-grade dysplasia, high-grade dysplasia, and invasive adenocarcinoma obtained by microscopic dissection of 43 esophagectomy specimens. Amplification of c-myc was found in none of 29 specialized epithelial specimens, none of 23 low-grade dysplasia specimens, 6 of 24 high-grade dysplasia specimens, and 17 of 39 adenocarcinoma specimens. Our data indicate that amplification of c-myc is a late event in the metaplasia-dysplasia-carcinoma sequence in BE. Furthermore, determination of c-myc amplification may help identify high-risk patients who would benefit from intensified endoscopic surveillance or from immediate treatment.  相似文献   
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ObjectiveTo assess health equity-oriented COVID-19 reporting across Canadian provinces and territories, using a scorecard approach.MethodsA scan was performed of provincial and territorial reporting of five data elements (cumulative totals of tests, cases, hospitalizations, deaths, and population size) across three units of aggregation (province or territory level, health regions, and local areas) (15 “overall” indicators), and for four vulnerable settings (long-term care and detention facilities, schools, and homeless shelters) and eight social markers (age, sex, immigration status, race/ethnicity, healthcare worker status, occupational sector, income, and education) (180 “equity-related” indicators) as of December 31, 2020. Per indicator, one point was awarded if case-delimited data were released, 0.7 points if only summary statistics were reported, and 0 if neither was provided. Results were presented using a scorecard approach.ResultsOverall, information was more complete for cases and deaths than for tests, hospitalizations, and population size denominators needed for rate estimation. Information provided on jurisdictions and their regions, overall, tended to be more available (average score of 58%, “D”) than that for equity-related indicators (average score of 17%, “F”). Only British Columbia, Alberta, and Ontario provided case-delimited data, with Ontario and Alberta providing case information for local areas. No jurisdiction reported on outcomes according to patients’ immigration status, race/ethnicity, income, or education. Though several provinces reported on cases in long-term care facilities, only Ontario and Quebec provided detailed information for detention facilities and schools, and only Ontario reported on cases within homeless shelters and across occupational sectors.ConclusionOne year into the pandemic, socially stratified reporting for COVID-19 outcomes remains sparse in Canada. However, several “best practices” in health equity-oriented reporting were observed and set a relevant precedent for all jurisdictions to follow for this pandemic and future ones.Supplementary InformationThe online version contains supplementary material available at 10.17269/s41997-021-00496-6.  相似文献   
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