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21.
A case of bacterial endocarditis following percutaneous angiography and angioplasty of a subclavian artery stenosis is described. Septic complications following angiography and angioplasty, and the role of prophylactic antibiotics are discussed.  相似文献   
22.
Is There an Advantage to Repairing Infected Mitral Valves?   总被引:5,自引:0,他引:5  
Background. The therapy for native mitral valve endocarditis is in evolution. Antibiotics have significantly improved survival rates, but patients with complications of endocarditis may require surgical treatment.

Methods. Between January 1985 and December 1995, 146 patients underwent surgical therapy (repair or replacement) for native mitral valve endocarditis. All patients had documented bacterial endocarditis. Univariate and multivariate analyses were performed to determine predictors of hospital death, long-term event-free survival, and probability of repair. Patients were evaluated in three groups: all patients, patients with acute endocarditis, and patients with chronic endocarditis.

Results. There were ten hospital deaths (6.8%). Patients undergoing repair had a lower hospital mortality rate (p = 0.008) then those having replacement. Event-free survival was improved after mitral valve repair in the overall group (p = 0.02) and in the group with healed (chronic) endocarditis (p = 0.05). Although the acute endocarditis group demonstrated an improved event-free survival rate after mitral valve repair versus replacement (74% versus 20% at 6 years), this did not reach statistical significance.

Conclusions. We conclude that mitral valve repair is preferable to mitral valve replacement when possible, in patients with complications of endocarditis, as repair results in a lower hospital mortality and an improved long-term survival.  相似文献   

23.
A case of active prosthetic valve infective endocarditis (PVE) due toCandida glabrata was successfully treated by the systemic administration of fluconazole. A 66-year-old Japanese man with infective endocarditis of unknown etiology underwent aortic and mitral valve replacement to treat severe aortic and mitral regurgitation associated with multiple organ failure. Postsurgical cultures of arterial blood were repeatedly positive forC. glabrata, and therefore fluconazole was administered either intravenously or orally at a dose of 400 mg/day for 46 days. During that time the signs of inflammation including fever such as an elevated white blood cell count and the presence of C-reactive protein (CRP) all improved while the blood cultures became negative. Fluconazole is thus considered to be effective in treating PVE caused byC. glabrata. When administering this treatment, it is also important to monitor the patient's renal and liver function.  相似文献   
24.
人工心脏瓣膜感染性心内膜炎临床分析   总被引:1,自引:0,他引:1  
目的 探讨人工心脏瓣膜感染性心内膜炎 (PVE)的临床特征 ,提高PVE的诊治水平。方法 通过分析 2 6例PVE的临床表现 ,分析其治疗和预后情况。结果 PVE临床不少见 ,发热是最常见的临床表现 ( 92 .3 % ) ,其次是贫血 ( 88.5% ) ,栓塞 ( 2 6.9% )。血培养和超声心动图是诊断PVE的重要手段 ,阳性率分别为 46.2 %和 73 .1%。早期PVE较晚期PVE预后差、死亡率高 ,分别为 66.7%、3 3 .3 %。主张早期、大剂量、长疗程的抗生素治疗 ,早期手术治疗可改善预后。本组病人总死亡率 3 4 .7% ,死亡原因 :心力衰竭 ( 77.8% )、栓塞 ( 2 2 .2 % )。结论 PVE预后差、死亡率高 ,应早期预防、早期诊断、早期治疗  相似文献   
25.
The article describes a relatively rare congenital anomaly that was difficult to diagnose in a 10-year-old child with acute nonlymphoblastic leukemia. Just at diagnosis of leukemia, the patient showed a pathologic chest radiograph because of a parenchymal thickening at the right lung apex. The presence of bronchopneumonia was suspected, and broad-spectrum antibiotic therapy was started with subsequent antifungal treatment for persistent fever and concurrent chemotherapy-induced marrow aplasia, which did not favor pulmonary infiltrate recovery. Continuous culture tests, including bronchial swab, proved negative for Koch-Weeks bacillus, fungal organisms, and other pathogens. Computed tomography, however, was suggestive of Aspergillus lung involvement, and apical sepmentectomy was performed. The anatomic pathologist suggested the diagnosis of intralobar sequestration. In summary, when pulmonary pathology with an excavation is found in a leukemic child, one must consider the possibility of pulmonary sequestration complicated by an infectious disease.  相似文献   
26.
The effect of acute infection of mice with lactic dehydrogenase virus (LDV) on two major functions of peritoneal macrophages was tested. Using a macrophage-dependent T cell proliferative assay to test the antigen-presenting capacity of LDV-infected macrophages we found that LDV impairs the capacity of antigen-presenting cells to trigger memory T lymphocytes. Endocytosis of antigen by LDV-infected macrophages was similar to that of uninfected cells. In addition, the proportion of intracellular antigen versus membrane-bound antigen in LDV-infected cells were similar to that observed in uninfected mice. It appears therefore, that the impaired immunogenic effect of LDV-infected macrophages results from reduced immunogenicity of the membrane-bound antigen.Testing the phagocytic activity of peritoneal macrophages we found that the uptake of radiolabeled antibody-coated sheep erythrocytes or bacteria (E. coli) by infected cells was similar to that by uninfected macrophages. In addition, LDV failed to affect the ability of peritoneal macrophages in a nitroblue tetrazolium reduction reaction which serves as an alternative parameter for measuring phagocytic activity. Our results support the assumption that LDV, which probably propagates in the cells of the reticuloendothelial system, impairs some of the immunogenic functions of macrophages and thereby affects macrophage-dependent immune responses.  相似文献   
27.

Background

Since its sudden appearance and link to microcephaly in 2015, the number of PubMed references for Zika virus (ZIKV) has risen from 181 to 5163, at time of writing, with a vast proportion focused on the consequences of ZIKV infection during pregnancy. This level of attention underlies increased demand for sensitive and specific diagnostic tools able to assess risk to an unborn child, as well as to understand the dynamics and consequences of viral persistence.

Aim

Review the expanding knowledge on ZIKV persistence and diagnostic challenges and summarize current advancements in detection.

Sources

Peer-reviewed articles based on the search terms ‘Zika’ and ‘ZIKV’ combined with the terms ‘diagnostics’ ‘point-of-care diagnostics’ ‘viral load’ ‘persistence’ ‘detection’ ‘treatment’ ‘nucleic acid amplification testing’ ‘microsphere’ ‘PVRT’ ‘RVNT’ ‘RT-LAMP’ ‘NASBA’ SIBA’ ‘RPA’ ‘SHERLOCK’ ‘ELISA’, and ‘TMA’ as well as laboratory experience of the authors.

Content

Topics covered include the emergence of the ZIKV epidemic, pathogenesis of ZIKV infection, the nature of ZIKV persistence, complications in serological diagnosis, tried and novel diagnostic laboratory techniques, and a recent accounting of point-of-care testing (POCT) methods.

Implications

Surveillance and research in the case of ZIKV has shifted into a more rapid and coordinated worldwide directive than has occurred with most viral epidemics to date. The particular concentration of outbreaks in resource-limited settings increases the need for simple assays capable of reliable, inexpensive, high-throughput ZIKV diagnosis. This review serves to both catalogue current diagnostic options and consider their suitability at point-of-care.  相似文献   
28.
The full-length infectious cDNA clone was constructed and sequenced from the strain DM of echovirus 9, which was recently isolated from a 6-week-old child at the clinical onset of type 1 diabetes. Parallel with the isolate DM, the full-length infectious cDNA clone of the prototype strain echovirus 9 Barty (Barty-INF), was constructed and sequenced. Genetic relationships of the sequenced echo 9 viruses to the other members of the human enterovirus type B species were studied by phylogenetic analyses. Comparison of capsid protein sequences showed that the isolate DM was closely related to both prototype strains: Hill and Barty-INF. The only exception was the inner capsid protein VP4 where serotype specificity was not evident and the isolate DM clustered with the strain Hill and the strain Barty-INF with echovirus 30 Bastianni. Likewise, the nonstructural protein coding region, P2P3, of isolate DM was more similar to strain Hill than to strain Barty-INF. However, like echovirus 9 Barty, the isolate DM contained the RGD-motif in the carboxy terminus of capsid protein VP1. By blocking experiments using an RGD-containing peptide and a polyclonal rabbit antiserum to the alpha(v)beta(3)-integrin, it was shown that this molecule works as a cellular receptor for isolate DM. By using primary human islets, it was shown that the isolate DM is capable of infecting insulin-producing beta-cells like the corresponding prototype strains did. However, only isolate DM was clearly cytolytic for beta-cells. The infectious clones that were made allow further investigations of the molecular features responsible for the diabetogenicity of the isolate DM.  相似文献   
29.
Abstract

Background: Systemic lupus erythematosus (SLE) is associated with a constellation of complications affecting multiple organs, including neuropsychiatric manifestations (NPSLE) and ischaemic events, leading to increased long-term morbidity. Antiphospholipid antibodies (aPL) are a major determinant of vascular inflammation and thromboembolic risk. The diagnostic role of anti-phosphatidylserine/prothrombin (aPS/PT) antibodies in this setting is incompletely defined.

Aim: To verify whether aPS/PT add to diagnostics and disease stratification in patients with SLE with or without other aPL.

Methods: 131 consecutive patients were studied, including 20 patients with SLE and secondary antiphospholipid syndrome (APS). aPS/PT IgG and IgM were assessed through ELISA and patients were stratified based on the presence of other aPL, on their clinical and laboratory features at time of blood sampling and on their clinical history. Synthetic indices of disease activity, chronic damage and cardiovascular risk were calculated at time of venipuncture.

Results: Fifty-one (38.9%) patients with SLE had aPS/PT and 15 (11.5%) patients had aPS/PT as the only aPL (aPS/PT-only). aPS/PT-only patients had a significantly higher prevalence of NPSLE than quadruple aPL-negative patients (p?=?.007). Patients with aPS/PT were more likely to have a history of ischaemia, thrombocytopenia and Libman–Sacks’ endocarditis. The presence of aPS/PT also associated with previous accrual of at least one damage item (p?=?.043), but had limited predictive values for damage progression in the short term.

Conclusion: aPS/PT antibodies provide non-redundant information that could contribute to risk assessment and stratification of patients with SLE.  相似文献   
30.
Cytotoxic T lymphocytes (CTL) with the CD4+ phenotype that recognize major histocompatibility complex (MHC) class II antigens are detectable very frequently in cultures of human alloreactive or virus-specific T cells. The significance of these CD4+ CTL for an immune reaction in vivo is not clear. Since Epstein-Barr virus (EBV) transformed B cells express HLA-class I and class II antigens equally well both CD8+ and CD4+ CTL should be stimulated during an acute EBV infection. We analysed the MHC specificity and the phenotype of EBV-specific CTL from patients with infectious mononucleosis (IM). When tested directly without any previous culture, T cells from patients in the acute phase of IM showed specific MHC-restricted cytotoxicity against the autologous B cell line. Addition of a HLA class I specific monoclonal antibody (MoAb) but not of a HLA class II specific MoAb resulted in a complete blocking of the lytic activity. Cell sorting revealed that the entire cytotoxic activity was present in the CD8+ fraction whereas no specific CTL were detectable in the CD4+ fraction. The absence of cytotoxicity in CD4+ cells was not due to a lack of activation of these cells since both CD8+ and CD4+ cells were activated in situ, showing spontaneous growth in interleukin-2 (IL-2) and expressing the activation marker TP103. Frequency estimation revealed that 1/300-1/600 CD8+ but only 1/2000-1/4000 CD4+ T cells gave rise to a specific CTL colony after 10 days. If CD4+ colonies were tested repeatedly for cytotoxicity we found that CD4+ CTL acquired their cytotoxicity during in vitro culture. In addition, we isolated EBV-specific CD4+ T cell clones able to lyse their stimulator cells in the presence but not in the absence of lectin, even after a long period of culture. Taken together our results show that cytotoxicity mediated by CD4+ T cells does not play a role in an anti-viral immune response.  相似文献   
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