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991.
Antibiotic resistance genes and Salmonella genomic island 1 in Salmonella enterica serovar Typhimurium isolated in Italy 下载免费PDF全文
Carattoli A Filetici E Villa L Dionisi AM Ricci A Luzzi I 《Antimicrobial agents and chemotherapy》2002,46(9):2821-2828
Fifty-four epidemiologically unrelated multidrug-resistant Salmonella enterica serovar Typhimurium isolates, collected between 1992 and 2000 in Italy, were analyzed for the presence of integrons. Strains were also tested for Salmonella genomic island 1 (SGI1), carrying antibiotic resistance genes in DT104 strains. A complete SGI1 was found in the majority of the DT104 strains. Two DT104 strains, showing resistance to streptomycin-spectinomycin and sulfonamides, carried a partially deleted SGI1 lacking the flo(st), tetR, and tetA genes, conferring chloramphenicol-florfenicol and tetracycline resistance, and the integron harboring the pse-1 gene cassette, conferring ampicillin resistance. The presence of SGI1 was also observed in serovar Typhimurium strains belonging to other phage types, suggesting either the potential mobility of this genomic island or changes in the phage-related phenotype of DT104 strains. 相似文献
992.
993.
Miquel Félez Nuria Grau Antonia Ruiz Encarna Guardiola Carles Sanjuas Cristina Estirado Maribel Navarro-Muñoz Antoni Pascual Mauricio Orozco-Levi Joaquim Gea 《Archivos de bronconeumología》2018,54(5):255-259
Introduction
Tissue hypoxia stimulates the production of erythropoietin (EPO), the main effect of which is, in turn, to stimulate erythropoiesis. Sleep apnea-hypopnea syndrome (SAHS) is an entity characterized by repeated episodes of hypoxemia during sleep.Objective
To analyze whether hypoxemia stimulated increased urinary excretion of EPO, and if so, to evaluate if treatment with continuous positive airway pressure (CPAP) can inhibit this phenomenon.Methods
We studied 25 subjects with suspected SAHS who underwent a polysomnography study (PSG). EPO levels in first morning urine (uEPO) and blood creatinine and hemoglobin were determined in all patients. Patients with severe SAHS repeated the same determinations after CPAP treatment.Results
Twelve subjects were diagnosed with severe SAHS (mean ± SD, AHI 53.1 ± 22.7). Creatinine and hemoglobin levels were normal in all subjects. uEPO was 4 times higher in the SAHS group than in the control group (1.32 ± 0.83 vs. 0.32 ± 0.35 UI/l, p <.002). CPAP treatment reduced uEPO to 0.61 ± 0.9 UI/l (p <.02), levels close to those observed in healthy subjects. No dose-response relationship was observed between severity of PSG changes and uEPO values.Conclusions
Patients with severe SAHS show increased uEPO excretion, but this normalizes after treatment with CPAP. 相似文献994.
George J. A. ten Bosch Jan H. Kessler Johanna Blom Antonia M. Joosten Carlo Gambacorti-Passerini Cornelis J. M. Melief & Onno C. Leeksma 《British journal of haematology》1998,103(4):1109-1115
Constitutive tyrosine phosphorylation of CrkL was recently demonstrated in platelets from chronic myelogenous leukaemia (CML) patients but BCR-ABL tyrosine kinase could not be detected in the platelet lysates. We studied platelets from 14 CML patients with different types of BCR-ABL mRNA and with maximal platelet counts ranging from 149 to 3069 × 109 /l. P2l0BCR-ABL protein was detected by Western blotting in platelet lysates of 12/13 CML patients with active disease but not in the lysate of platelets from a Ph-positive acute lymphoblastic leukaemia (ALL) patient in remission or eight BCR-ABL-negative controls including one essential thrombocythaemia (ET) patient. Immunoblotting of p2l0BCR-ABL -positive platelets lysates with anti-CrkL antibody revealed a CrkL triplet consisting of one unphosphorylated and two phosphorylated forms of the protein. This CrkL phosphorylation pattern was not observed in normal platelets or CML platelets treated with ABL tyrosine kinase inhibitor CGP57148B. The presence of BCR-ABL provides an explanation for the constitutive tyrosine phosphorylation of CrkL in CML platelets. As no correlation was observed between platelet counts and platelet BCR-ABL protein expression, thrombocytosis or thrombocythaemia in CML cannot be explained by constitutive BCR-ABL-mediated CrkL tyrosine phosphorylation. 相似文献
995.
Dr. Francesco Narducci MD Gabrio Bassotti MD Maria Teresa Granata MD Maria Antonia Pelli MD Manuela Gaburri MD Renato Palumbo MD Antonio Morelli MD 《Digestive diseases and sciences》1986,31(3):241-246
This study was undertaken to evaluate (1) the colonic response to eating for a prolonged time in healthy subjects and patients with the irritable bowel syndrome (IBS); (2) the effect of octylonium bromide, a new smooth muscle relaxant acting by interfering with calcium ion mobilization, on the postprandial colonic motility; and (3) whether chronic gastric stasis could be responsible for both the dyspeptic symptoms often complained of by IBS patients and the faulty colonic response to eating. The colonic response to a 1000-kcal mixed meal in ten healthy subjects was characterized by two transient (from 0 to 60 and from 120 to 150 min postprandially, respectively) increases in colonic motor activity; ten IBS patients showed a continuous postprandial increase in colonic motor activity that was not terminated 180 min after eating. Treatment of IBS patients with octylonium bromide (80 mg, qid,per os) for 5–7 days reduced their colonic response to eating to a very short increase in colonic motor activity limited to the first 30 min. Finally, gastric emptying was not different in the two groups. 相似文献
996.
Salvatore Pirelli MD Gian B. Danzi MD Antonia Alberti MD Daria Massa MD Giacomo Piccal MD Francesco Faletra MD Eugenio Picano MD Luigi Campolo MD Claudio De Vita MD 《The American journal of cardiology》1991,67(16):1335-1338
The present study compares the relative usefulness of the maximal treadmill exercise electrocardiography test with the high-dose dipyridamole echocardiography test (echocardiographic monitoring during dipyridamole infusion up to 0.84 mg/kg in 10 minutes) in detecting severe restenosis or coronary artery disease progression (>70% stenosis) in asymptomatic patients 12 months after a primary successful coronary angioplasty. Criteria of positivity were: for the exercise electrocardiography test, an ST-segment shift ≥0.1 mV from baseline, 0.08 second from the J point; for the dipyridamole echocardiography test, a transient dyssynergy of contraction, absent or of a lesser degree than that in the baseline examination. The exercise electrocardiography and dipyridamole echocardiography tests revealed a similar feasibility (91 vs 87%, difference not significant). Both tests could be performed in 75 patients. For detection of restenosis or disease progression, or both, the exercise electrocardiography test revealed a sensitivity similar to the dipyridamole echocardiography test (71 vs 71%, difference not significant), but a lower specificity (61 vs 90%). It is concluded that the high-dose dipyridamole echocardiogrphy test is equally feasible but more accurate than the exercise electrocardiography test for noninvasive detection of severe asymptomatic restenosis or disease progression at 1 year after successful coronary angioplasty. 相似文献
997.
998.
Expression of adhesion molecules during apoptosis of circulating neutrophils in COPD 总被引:8,自引:0,他引:8
STUDY OBJECTIVES: Neutrophil accumulation occurs in the lungs of patients with COPD. This can be due to increased recruitment and/or delayed tissue clearance. Previous studies have described alterations in circulating neutrophils in these patients that can facilitate the former. Dysregulation of neutrophil apoptosis may contribute to the latter. This study investigated the potential abnormalities of the apoptotic process in COPD patients. DESIGN: Prospective study. SETTINGS: Outpatient clinic in a urban, tertiary hospital. PATIENTS: Fourteen stable patients with COPD, 8 smokers with normal lung function, and 8 healthy nonsmoking subjects. MEASUREMENTS AND RESULTS: We cultured circulating neutrophils that had been harvested from the study subjects at 2, 6, and 24 h. Apoptosis was assessed using flow cytometry by annexin binding and CD16 expression. The surface expression of the adhesion molecules Mac-1 (CD11b) and L-selectin (CD62L) also was determined by flow cytometry. The percentage of apoptotic neutrophils increased with time similarly in all groups. However, the surface expression of Mac-1 (CD11b) was higher, and that of L-selectin (CD62L) was lower, during apoptosis in the neutrophils of patients with COPD. CONCLUSIONS: These results show that, quantitatively, in vitro neutrophil apoptosis in COPD patients occurred at a rate similar to that found in healthy individuals and smokers with normal lung function. Qualitatively, however, the increased surface expression of Mac-1 (CD11b) and the decreased surface expression of L-selectin (CD62L) observed in the apoptotic neutrophils of COPD patients indicate increased activation during the apoptotic process. This may be relevant for the pathogenesis of COPD. 相似文献
999.
1000.
T lymphocytes of recipient origin may contribute to the recovery of specific immune response toward viruses and fungi in children undergoing cord blood transplantation 下载免费PDF全文
Montagna D Locatelli F Moretta A Lisini D Previderè C Grignani P DeStefano P Giorgiani G Montini E Pagani S Comoli P Maccario R 《Blood》2004,103(11):4322-4329
Patients undergoing allogeneic cord blood transplantation (CBT) benefit from a low risk of graft-versus-host disease (GVHD), but there are still concerns that they be able to recover an effective immune capacity early after transplantation. We investigated the ability to develop in vitro T-lymphocyte-mediated immune response toward human cytomegalovirus and Candida albicans antigens, early and late after transplantation, in children given cord blood transplants from either an HLA-identical sibling or an unrelated donor. Proliferative capacity and frequency of antigen-specific T cells were evaluated; antigen-specific CD4(+) T-cell clones were also generated and characterized for T-cell receptor repertoire diversity, cytokine phenotype, and their origin (either from donor or patient). We found that the majority of recipients can develop a specific response to viral or fungal antigens already early after transplantation. Antigen-specific T-cell clones of both donor and recipient origin contributed to the reconstitution of immune response. Antigen-specific T lymphocytes of recipient origin were detected in patients receiving a transplant from a relative, after a chemotherapy-based conditioning regimen, and who did not have GVHD. Our results document, at a clonal level, that after CBT recovery of either polyclonal or pauciclonal T-cell response toward widespread pathogens is prompt, with some patients benefiting from a contribution of recipient-derived cells. 相似文献