Objective Acquired aplastic anemia(aAA)is characterized by an autologous immunological attack against hematopoietic stem and progenitor cells,and immunotolerance disruption is frequent,with reduced T regulatory cells(...Objective Acquired aplastic anemia(aAA)is characterized by an autologous immunological attack against hematopoietic stem and progenitor cells,and immunotolerance disruption is frequent,with reduced T regulatory cells(Tregs)frequencies and increased effector cytotoxic cells.Tregs are reduced in aAA and increase in number after successful immunosuppressive therapies.Methods In this retrospective study,we investigated the frequency of circulating Tregs by multiparametric flow cytometry immunophenotyping in non-severe aAA patients before and after immunosuppressive therapy.The samples were stained with the following antibodies:ECD anti-CD3,PE or PC5 anti-CD4,FITC anti-CD8,and PE anti-CD25,and Tregs were identified by first gating on linear parameters for lymphocyte identification and then for CD3 expression.In CD3+CD4+cells,Tregs were further identified on the basis of CD25 and FOXP3 expression.Results Although the number of Tregs tended to increase after immunosuppressive treatments,their circulating frequency remained lower than that of healthy subjects,regardless of their responsiveness to therapies.Moreover,the relative frequency combined with absolute Treg counts might be more informative in the differential diagnosis of bone marrow failure syndromes.Conclusions The persistent decrease in circulating Tregs could be the result of immunosuppressive agents that could preferentially expand other T-cell subsets.At the same time,an imbalance in immunotolerance might persist,which is also favored by chronic antigen stimulation.展开更多
Acquired resistance of mycoplasmas to antibiotics constitutes a major health problem in the world in general and in Africa in particular. Despite the diversity of kits marketed, several of them evaluating the sensitiv...Acquired resistance of mycoplasmas to antibiotics constitutes a major health problem in the world in general and in Africa in particular. Despite the diversity of kits marketed, several of them evaluating the sensitivity of mycoplasmas to antibiotics continue to present resistance, in this case, the Mycoplasma IST2. In order to overcome this resistance, a new kit (Mycoplasma IST3) has been developed in accordance with the new Clinical and Laboratory Standard Institute (CLSI) recommendations. The objective of the study was to determine the resistance profile of urogenital Mycoplasmas to antibiotics using this new kit and to highlight cases of co-infections in comparison with the Mycoplasma IST2. Over a period of four mo nths, one hundred and one (101) samples of urogenital secretions were collected (from sexually active men and women) and analyzed. Culture and antibiotic susceptibility testing were performed in a liquid medium using the Mycoplasma IST2 and Mycoplasma IST3 Tests according to the manufacturer’s recommendations. Among the different samples analyzed, we noted a mycoplasma positivity rate of 71.29% with a predominance of infection in women, i.e. 86.12% compared to men 13.88%. Ureaplasma spp was the most encountered germ with a rate of 62.50% followed by cases of co-infections at 33.33% (Uspp/Mh) and the least encountered was Mycoplasma hominis with a rate of 2.79%. We analyzed 25 samples, among which we had 4 co-infections, simultaneously using the two kits in the same patients. The distribution of cases between the two kits was equivalent. We noted a significant rate of resistance to erythromycin 100% using Mycoplasma IST2. However, no resistance was observed in erythromycin with Mycoplasma IST3. Mycoplasma IST2 also showed resistance to fluoroquinolones, which was not the case for Mycoplasma IST3 which did not show any resistance to fluoroquinolones. Both kits showed resistance to tetracycline. The antibiotic sensitivity test using the Mycoplasma IST3 revealed a high rate of resistance to tetracycline, i.e. 57.14% and 91.67% for Ureaplasma spp and Mycoplasma hominis respectively. Resistance rates to other antibiotics were less than 25%. This study was able to demonstrate that Mycoplasma IST3 constitutes a better therapeutic choice compared to its predecessor Mycoplasma IST2, because it eliminated the biggest shortcoming of its predecessor.展开更多
文摘Objective Acquired aplastic anemia(aAA)is characterized by an autologous immunological attack against hematopoietic stem and progenitor cells,and immunotolerance disruption is frequent,with reduced T regulatory cells(Tregs)frequencies and increased effector cytotoxic cells.Tregs are reduced in aAA and increase in number after successful immunosuppressive therapies.Methods In this retrospective study,we investigated the frequency of circulating Tregs by multiparametric flow cytometry immunophenotyping in non-severe aAA patients before and after immunosuppressive therapy.The samples were stained with the following antibodies:ECD anti-CD3,PE or PC5 anti-CD4,FITC anti-CD8,and PE anti-CD25,and Tregs were identified by first gating on linear parameters for lymphocyte identification and then for CD3 expression.In CD3+CD4+cells,Tregs were further identified on the basis of CD25 and FOXP3 expression.Results Although the number of Tregs tended to increase after immunosuppressive treatments,their circulating frequency remained lower than that of healthy subjects,regardless of their responsiveness to therapies.Moreover,the relative frequency combined with absolute Treg counts might be more informative in the differential diagnosis of bone marrow failure syndromes.Conclusions The persistent decrease in circulating Tregs could be the result of immunosuppressive agents that could preferentially expand other T-cell subsets.At the same time,an imbalance in immunotolerance might persist,which is also favored by chronic antigen stimulation.
文摘Acquired resistance of mycoplasmas to antibiotics constitutes a major health problem in the world in general and in Africa in particular. Despite the diversity of kits marketed, several of them evaluating the sensitivity of mycoplasmas to antibiotics continue to present resistance, in this case, the Mycoplasma IST2. In order to overcome this resistance, a new kit (Mycoplasma IST3) has been developed in accordance with the new Clinical and Laboratory Standard Institute (CLSI) recommendations. The objective of the study was to determine the resistance profile of urogenital Mycoplasmas to antibiotics using this new kit and to highlight cases of co-infections in comparison with the Mycoplasma IST2. Over a period of four mo nths, one hundred and one (101) samples of urogenital secretions were collected (from sexually active men and women) and analyzed. Culture and antibiotic susceptibility testing were performed in a liquid medium using the Mycoplasma IST2 and Mycoplasma IST3 Tests according to the manufacturer’s recommendations. Among the different samples analyzed, we noted a mycoplasma positivity rate of 71.29% with a predominance of infection in women, i.e. 86.12% compared to men 13.88%. Ureaplasma spp was the most encountered germ with a rate of 62.50% followed by cases of co-infections at 33.33% (Uspp/Mh) and the least encountered was Mycoplasma hominis with a rate of 2.79%. We analyzed 25 samples, among which we had 4 co-infections, simultaneously using the two kits in the same patients. The distribution of cases between the two kits was equivalent. We noted a significant rate of resistance to erythromycin 100% using Mycoplasma IST2. However, no resistance was observed in erythromycin with Mycoplasma IST3. Mycoplasma IST2 also showed resistance to fluoroquinolones, which was not the case for Mycoplasma IST3 which did not show any resistance to fluoroquinolones. Both kits showed resistance to tetracycline. The antibiotic sensitivity test using the Mycoplasma IST3 revealed a high rate of resistance to tetracycline, i.e. 57.14% and 91.67% for Ureaplasma spp and Mycoplasma hominis respectively. Resistance rates to other antibiotics were less than 25%. This study was able to demonstrate that Mycoplasma IST3 constitutes a better therapeutic choice compared to its predecessor Mycoplasma IST2, because it eliminated the biggest shortcoming of its predecessor.
