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101.
We have recently shown that the use of allogeneic granulocyte colony-stimulating factor (G-CSF)-mobilized peripheral blood hematopoietic stem cell transplantation (PBHSCT), as compared with bone marrow transplantation (BMT), is associated with increased titers of antibodies (Abs) directed against red blood cell ABO antigens. To further evaluate the influence of a G-CSF-mobilized PBHSCT graft on alloimmune Ab responses, we examined the frequency of anti-HLA Abs after transplantation in the setting of the same randomized study, comparing PBHSCT with BMT in adults. Anti-HLA Ab presence was determined by complement-dependent cytotoxicity assay (CDC) and flow cytometry in the recipient before and 30 days after transplantation as well as in the donor before graft donation. The use of PBHSCT was significantly associated with increased detection of anti-HLA immunoglobulin G (IgG) Abs early after transplantation as evidenced by flow cytometry (11 of 24 versus 4 of 27 transplant recipients, P =.03) and, less so, by CDC (5 of 24 versus 1 of 27 transplant recipients, P =.09). The difference between PBHSCT and BMT was further heightened when analysis was restricted to anti-HLA IgG Ab-negative donor/recipient pairs. In such a setting, early anti-HLA Ab was never detected after BMT but was repeatedly detected after PBHSCT (flow cytometry, 6 of 18 versus 0 of 17 transplant recipients, P =.02; CDC, 4 of 23 versus 0 of 26 transplant recipients, P =.04). Importantly, the PBHSCT-associated increase in anti-HLA Ab detection was observed despite a reduction in the median number of platelet-transfusion episodes per patient in PBHSC transplant versus BM transplant recipients (3 platelet-transfusion episodes [range, 1-21] in PBHSCT group vs 6 platelet-transfusion episodes [range, 3-33] in the BMT group; P =.02). In conclusion, this study strongly suggests that G-CSF-mobilized PBHSCT results in an increased incidence of circulating anti-HLA Abs and further confirms that the use of such a graft alters alloimmune Ab responses.  相似文献   
102.
This paper proposes a multigrid inversion framework for quantitative photoacoustic tomography reconstruction. The forward model of optical fluence distribution and the inverse problem are solved at multiple resolutions. A fixed-point iteration scheme is formulated for each resolution and used as a cost function. The simulated and experimental results for quantitative photoacoustic tomography reconstruction show that the proposed multigrid inversion can dramatically reduce the required number of iterations for the optimization process without loss of reliability in the results.OCIS codes: (170.3880) Medical and biological imaging, (170.5120) Photoacoustic imaging, (170.6960) Tomography  相似文献   
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This study was conducted from September 2011 to March 2014 to address the occurrence and genotypes of Coxiella burnetii using molecular methods in ticks collected from domestic animals in Ethiopia. Ticks were tested for C. burnetii by quantitative real-time polymerase chain reaction (qPCR) targeting two different genes followed by multispacer sequence typing (MST). An overall prevalence of 6.4% (54/842) of C. burnetii was recorded. C. burnetii was detected in 28.6% (14/49) of Amblyomma gemma, 25% (31/124) of Rhipicephalus pulchellus, 7.1% (1/14) of Hyalomma marginatum rufipes, 3.2% (2/62) of Am. variegatum, 3.1% (4/128) of Am. cohaerens, 1.6% (1/63) of Rh. praetextatus, and 0.6% (1/153) of Rhipicephalus (Boophilus) decoloratus. Significantly higher overall frequencies of C. burnetii DNA were observed in Am. gemma and Rh. pulchellus than in other tick species (Mantel–Haenszel [MH], P < 0.0001). The overall frequency of C. burnetii was significantly higher (MH, P < 0.0001) in ticks from southeastern districts (Arero, Moyale, and Yabelo) than that from other districts. This study demonstrated the presence of C. burnetii genotype MST 18 in ticks in southeastern districts and genotype MST 20 in ticks in central districts. This study highlights the importance of ticks in the epidemiology of C. burnetii in Ethiopia.  相似文献   
106.
Prospectively collected, contemporary data are lacking on how the features of infective endocarditis (IE) vary according to region. We, therefore, compared IE in Rennes, France and Khon Kaen, Thailand. Fifty-eight patients with confirmed IE were enrolled at each site during 2011 and 2012 using a common protocol. Compared with French patients, Thais had a lower median age (47 versus 70 years old; P < 0.001) and reported more animal contact (86% versus 21%; P < 0.001). There were more zoonotic infections among Thai than France patients (6 and 1 cases; P = 0.017) and fewer staphylococcal infections (4 versus 15 cases; P = 0.011). Underlying rheumatic heart disease was more prevalent in Thai than in French patients (31% and 4%; P = 0.001), whereas prosthetic heart valves were less prevalent (9% and 35%; P = 0.001). Our data strengthen previous observations that IE in the tropics has distinctive demographic characteristics, risk factors, and etiologies and underscore the need for improved prevention and control strategies.  相似文献   
107.
Rift Valley fever (RVF) is a viral zoonotic disease occurring throughout Africa, the Arabian Peninsula, and Madagascar. The disease is caused by a Phlebovirus (RVF virus [RVFV]) transmitted to vertebrate hosts through the bite of infected mosquitoes. In Madagascar, the first RVFV circulation was reported in 1979 based on detection in mosquitoes but without epidemic episode. Subsequently, two outbreaks occurred: the first along the east coast and in the central highlands in 1990 and 1991 and the most recent along the northern and eastern coasts and in the central highlands in 2008 and 2009. Despite the presence of 24 mosquitoes species potentially associated with RVFV transmission in Madagascar, little associated entomological information is available. In this review, we list the RVFV vector, Culex antennatus, as well as other taxa as candidate vector species. We discuss risk factors from an entomological perspective for the re-emergence of RVF in Madagascar.  相似文献   
108.
Infection in breast implants   总被引:8,自引:0,他引:8  
Infection is the leading cause of morbidity that occurs after breast implantation and complicates 2.0-2.5% of interventions in most case series. Two-thirds of infections develop within the acute post-operative period, whereas some infections may develop years or even decades after surgery. Infection rates are higher after breast reconstruction and subsequent implantation than after breast augmentation. Risk factors for infection associated with breast implantation have not been carefully assessed in prospective studies with long-term follow-up. Surgical technique and the patient's underlying condition are the most important determinants. In particular, breast reconstruction after mastectomy and radiotherapy for cancer is associated with a higher risk for infection. The origin of infection in women with implants remains difficult to determine, but potential sources include a contaminated implant, contaminated saline, the surgery itself or the surgical environment, the patient's skin or mammary ducts, or, as suggested by many reports, seeding of the implant from remote infection sites. Late infection usually results from secondary bacteraemia or an invasive procedure at a location other than breasts. Diagnostic and management strategies are proposed and the value of peri-operative surgical prophylaxis is revisited. The current hypothesis of the possible role of low-grade or subclinical infection in the origin of capsular contracture is also reviewed.  相似文献   
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BACKGROUND: Biochemical markers for liver fibrosis (FibroTest) and necroinflammatory features (ActiTest) are an alternative to liver biopsy in patients with chronic hepatitis C. Our aim was to assess the inter-laboratory variability of these tests, and their 6 components (gamma-glutamyl transpeptidase, alanine aminotransferase, alpha2-macroglobulin, haptoglobin, apolipoprotein A1, and total bilirubin) and to identify factors associated with this variability. RESULTS: Serum of 24 patients with chronic hepatitis C or severe alcoholic liver disease were prospectively recorded and analyzed in one reference center and in 8 additional laboratories. When gamma-glutamyl transpeptidase and alanine aminotransferase were expressed in international units, there was no significant difference between laboratories in the results of FibroTest or ActiTest; kappa statistics were greater than 0.50 with only 0.8% of cases (3/384) with a discordance of more than one stage. The main factor significantly associated with variability was the expression of gamma-glutamyl transpeptidase and alanine aminotransferase, as multiples of upper limit of reference values. The use of standardized method with pyridoxal phosphate reduced the variability of alanine aminotransferase expression, and standardized original Szasz method reduced the variability of gamma-glutamyl transpeptidase expression. CONCLUSIONS: The variability of FibroTest and ActiTest was acceptable without clinical consequences for the prediction of the stage of liver fibrosis and grade of activity. Standardized methods and assay calibration should be used and expression of alanine aminotransferase and gamma-glutamyl transpeptidase in multiples of the upper limit of reference values should not be employed.  相似文献   
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