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51.
Association of human polyomavirus JC with peripheral blood of immunoimpaired and healthy individuals
Drries Kristina Sbiera Silviu Drews Klaus Arendt Gabriele Eggers Christian Drries Rdiger 《Journal of neurovirology》2003,9(1):81-87
JC virus (JCV) infection is regularly asymptomatic in healthy individuals. In contrast, in immunocompromised individuals, highly activated virus replication may lead to PML. Peripheral blood cells (PBCs) are found to habor JCV DNA in healthy and diseased individuals and it is discussed that they might be responsible for dissemination of the virus to the central nervous system (CNS) during persistence. To better understand the role of JCV DNA in PBCs for persistent infection and pathogenesis, the authors characterized the extent of JCV infection in Ficoll-gradient purified blood cells (peripheral blood mononuclear cells [PBMCs]) of healthy and human immunodeficiency virus type 1 (HIV-1)-infected individuals. Virus activation in PBMCs from healthy JCV-infected individuals was found at a rate of 0% to 38% at low polymerase chain reaction (PCR) sensitivity. In progressive multifocal leukoencephalopathy (PML) patients, a stronger signal was found, indicating increased virus activation. JCV DNA was regularly detected in T and B lymphocytes and in monocytes at low levels. However, granulocytes were shown to be the predominant reservoir of JCV DNA harboring high copy numbers. Although the overall distribution of viral genomes holds true for the population studied, in the individual, a markedly changed pattern of distribution can be found. 相似文献
52.
J W van 't Wout E R de Graeff-Meeder L C Paul W Kuis R van Furth 《Scandinavian journal of infectious diseases》1988,20(2):193-198
Two patients with cryptococcal meningitis were treated with the investigational triazole drug fluconazole (UK-49,858). Cerebrospinal fluid (CSF) levels of fluconazole were between 3.0 and 5.4 mg/l 2 h after an oral dose of 50 mg daily in the first patient and between 7.9 and 9.0 mg/l after an oral dose of 100 mg daily in the second patient. These levels were in the same range as plasma levels. The first patient, a 46-year-old renal transplant patient, was both clinically and microbiologically cured after 28 weeks of therapy (follow-up 14 months). In the second patient, a 15-year-old girl with chronic mucocutaneous candidiasis, fluconazole led to clinical cure of the meningitis, but failed to eradicate cryptococci from the CSF. These cases illustrate that fluconazole is useful for the treatment of cryptococcal meningitis, especially when prolonged treatment is indicated as in patients with immunodeficiencies. 相似文献
53.
R F Lai A Fat M Harboe J C Chan Pin Jin M M Diesselhoff-den Dulk R van Furth 《International journal of leprosy and other mycobacterial diseases : official organ of the International Leprosy Association》1988,56(4):552-558
For the detection of the synthesis in vitro of anti-Mycobacterium leprae antibodies in various tissues of leprosy patients, biopsy specimens of skin lesions, nasal mucosa, larynx, lymph nodes, and bone marrow were cultured in a medium containing 14C-labeled lysine and isoleucine. The culture fluids were analyzed by crossed immunoelectrophoresis with intermediate gel and autoradiography. The results show that synthesis of anti-M. leprae antibodies occurs at the investigated sites of leprosy patients and that the specificities of the synthesized antibodies differ between sites in individual patients. It is conceivable that these antibodies play a role in the local defense against M. leprae. 相似文献
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Clear cell ependymoma is a rare and diagnostically challenging subtype of ependymoma, whose genetic features are essentially unknown. We studied 13 clear cell ependymomas (five cases WHO grade II, eight cases WHO grade III) by comparative genomic hybridization (CGH). Chromosomal imbalances were found in 12/13 cases. The most common aberrations overall were +1q (38%), -9 (77%), -3 (31%), and -22q (23%). Clear cell ependymomas of WHO grade II were characterized by -9 (40%), whereas WHO grade III cases mainly showed +1q (63%), and +13q (25%), as well as -9 (100%), -3 (38%), and -22q (25%). In contrast to other ependymal tumors, clear cell ependymomas of WHO grade II showed fewer imbalances than WHO grade III samples (1.4 vs 3.5 per case). Although some of the implicated chromosomes have previously been shown to be involved in other ependymoma variants, the striking frequency of +1q, -9, and -3 suggests that aberrations differ between clear cell and other types of ependymomas, in particular, for loss of chromosome 9 which can be regarded as the molecular hallmark of clear cell ependymomas. 相似文献
60.
Abstract: This review examines the liver-damaging side effects of anabolic-androgenic steroids (AAS). It seems that AAS can cause development of peliosis hepatis, subcellular changes of hepatocytes, hepatocellular hyperplasia and hepatocellular adenomas. On the other hand, it has not been convincingly proved that AAS can cause development of hepatocellular carcinomas when used in the usual therapeutic doses. Tumours reported as hepatocellular carcinomas caused by AAS seem to be hyperplastic lesions of a benign nature able to regress with withdrawal of the putative agent. The effects of untraditional combinations and high-dose AAS are not yet known, leaving the possibility of a carcinogenic effect in those cases. 相似文献