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11.
Regulation of Epstein-Barr virus infection by recombinant interferons. Selected sensitivity to interferon-gamma 总被引:12,自引:0,他引:12
Interferons (IFN) are antiviral proteins that may be important in mediating cellular defenses against Epstein-Barr virus (EBV) infection. However, the means by which IFN-alpha, -beta and -gamma modify EBV infectivity are not clear. We have evaluated the effects of purified recombinant preparations of all three classes of IFN on EBV-induced B lymphocyte proliferation and Ig secretion. When added early after EBV infection, all three recombinant IFN reduced B cell outgrowth and Ig secretion. IFN-gamma exerted a 7-10-fold more potent antiviral effect than IFN-alpha or -beta. All three types of IFN act directly on B cells. Monocytes and natural killer cells are not necessary for the anti-EBV activity. Of the three recombinant IFN, only IFN-gamma reduced EBV-induced proliferation and Ig secretion when added 3-4 days after virus infection; IFN-alpha/beta were only effective up to 24 h. B lymphoblastoid lines already transformed by EBV are insensitive to the anti-proliferative actions of all three types of IFN. On the basis of these findings, we propose three phases of regulation during EBV infection. In the early phase, EBV-infected cells can be regulated by all IFN. Subsequently, there is an intermediate period where only IFN-gamma is capable of directly affecting EBV-induced B cell responses. In the third phase, B lymphocytes become insensitive to direct actions of all IFN and are now subject to regulation only by cytotoxic cells. 相似文献
12.
Willinger B Kopetzky G Harm F Apfalter P Makristathis A Berer A Bankier A Winkler S 《Journal of clinical microbiology》2004,42(1):478-480
Disseminated infection with the coelomycetous fungus Nattrassia mangiferae is a very rare disease affecting only the immunocompromised host. We report the first case of a disseminated infection with spondylodiscitis and granular skin lesions due to N. mangiferae in a renal transplant patient. 相似文献
13.
Detection and identification of fungi from fungus balls of the maxillary sinus by molecular techniques 下载免费PDF全文
Willinger B Obradovic A Selitsch B Beck-Mannagetta J Buzina W Braun H Apfalter P Hirschl AM Makristathis A Rotter M 《Journal of clinical microbiology》2003,41(2):581-585
The aim of this study was to find a reliable method for the detection and identification of fungi in fungus balls of the maxillary sinus and to evaluate the spectrum of fungi in these samples. One hundred twelve samples were obtained from patients with histologically proven fungal infections; 81 samples were paraffin-embedded tissue sections of the maxillary sinus. In 31 cases, sinus contents without paraffin embedding were sent for investigation. PCR amplification with universal fungal primers for 28S ribosomal DNA and amplicon identification by hybridization with species-specific probes for Aspergillus fumigatus, Aspergillus flavus, Aspergillus niger, Aspergillus terreus, Aspergillus glaucus, Pseudallescheria boydii, Candida albicans, and Candida glabrata were performed for all samples. Furthermore, PCR products were sequenced. Fresh samples were also cultivated. Fungal DNA was detected in all of the fresh samples but only in 71 paraffin-embedded tissue samples (87.7%). Sequence analysis was the most sensitive technique, as results could be obtained for 28 (90.3%) fresh samples by this method in comparison to 24 (77.4%) samples by hybridization and 16 (51.6%) samples by culture. However, sequence analysis delivered a result for only 36 (50.7%) of the paraffin-embedded specimens. Hybridization showed reliable results for A. fumigatus, which proved to be the most common agent in fungus balls of the maxillary sinus. Other Aspergillus species and other genera were rarely found. 相似文献
14.
15.
Rohwer F Macmaster W Haseltine W Tsoukas C McGuire K 《International journal of oncology》1994,5(5):1163-1169
The retrovirus Human T cell Leukemia Virus type I (HTLV-I) is the causative agent of Adult T cell Leukemia Lymphoma (ATLL) and is associated with HTLV-I Myelopathy. HTLV-I mediated transformation of CD4(+) T cells, during the course of ATLL, is poorly understood. It has been suggested that HTLV-I is responsible for the immortalization of infected cells, but transformation is dependent on secondary events. To investigate this hypothesis, we have isolated an HTLV-I infected T cell line that is dependent on IL-2 for growth in tissue culture. Further, a subclone of this cell line that is able to grow in the absence of IL-2 has been isolated. Both cell lines have identical TCR chain rearrangements and cell surface markers. Each,cell line produces viral mRNAs and proteins. Finally, both of these cell lines are sensitive to rapamycin and cyclosporin A regardless of the presence of IL-2. We propose that this system will provide a unique opportunity to study transformation to IL-2 independence in HTLV-I infected cells. 相似文献
16.
Athanasios Zahariou Maria Karamouti George Karagiannis Polyanthi Papaioannou 《Journal of neurology》1995,242(Z2):S61-S62
Poster Session 1
Child neurology 相似文献17.
Meletios A Dimopoulos Vassilis L Souliotis Athanasios Anagnostopoulos Christos Papadimitriou Petros P Sfikakis 《Journal of clinical oncology》2005,23(19):4381-4389
PURPOSE: To quantitate the individual levels of melphalan-induced DNA damage formation and repair in vivo and to search for possible correlations with clinical outcome in patients with multiple myeloma (MM). PATIENTS AND METHODS: The formation and subsequent repair of DNA damage (monoadducts and interstrand cross-links) in the p53 tumor-suppressor gene, the proto-oncogene N-ras, and the housekeeping gene beta-actin during the first 24 hours after treatment with high-dose melphalan (HDM; 200 mg/m2) supported by autologous blood stem-cell transplantation (ABSCT) was measured in blood leukocytes of 26 patients with MM. The peak DNA adduct levels, the total amount of adducts over time, and the rate of adducts repair in each gene were correlated with response and time to progression after HDM. RESULTS: The levels of gene-specific DNA damage formation and the individual repairing capacity varied up to 16-fold among patients, indicating that the melphalan-induced biologic effect in vivo is highly individualized. A significantly greater DNA damage and a slower rate of repair in p53 for all end points under study were found in patients who achieved tumor reduction compared with nonresponding patients. Furthermore, longer progression-free survival correlated with increased peak monoadduct levels in the p53 gene (P = .032). CONCLUSION: Increased DNA damage and slower repairing capacity in the p53 gene from blood leukocytes after HDM correlate with improved outcome of patients with MM who undergo ABSCT. These results suggest that quantitation of such biologic end points may identify patients who are more likely to benefit from this procedure. 相似文献
18.
Athanasia Apsemidou Kerstin Rauwolf Athanasios Tragiannidis Angela Brentrup Manfred Schiborr Karsten Becker Martina Ahlmann Andreas H. Groll 《Pediatric blood & cancer》2019,66(4)
Bartonella henselae, the causative agent of cat‐scratch disease, has been recognized to be responsible for a broad range of clinical syndromes. We report the case of a patient with disseminated B. henselae infection mimicking Langerhans cell histiocytosis at presentation and its successful management with neurosurgery, prolonged antibacterial therapy, and observation. 相似文献
19.
Georgios Manessis Maciej Frant Grzegorz Wozniakowski Lapo Nannucci Martina Benedetti Lilla Denes Balka Gyula Athanasios I. Gelasakis Clare Squires Sara Recuero Carlos Sanchez Amadeu Griol Alessandro Giusti Ioannis Bossis 《Viruses》2022,14(5)
Swine viral diseases challenge the sector’s sustainability by affecting productivity and the health and welfare of the animals. The lack of antiviral drugs and/or effective vaccines renders early and reliable diagnosis the basis of viral disease management, underlining the importance of point-of-care (POC) diagnostics. A novel POC diagnostic device utilizing photonic integrated circuits (PICs), microfluidics, and information and communication technologies for the detection of porcine reproductive and respiratory syndrome virus (PRRSV) and swine influenza A (SIV) was validated using spiked and clinical oral fluid samples. Metrics including sensitivity, specificity, accuracy, precision, positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR) were calculated to assess the performance of the device. For PRRSV, the device achieved a sensitivity of 83.5%, specificity of 77.8%, and DOR values of 17.66, whereas the values for SIV were 81.8%, 82.2%, and 20.81, respectively. The POC device and PICs can be used for the detection of PRRSV and SIV in the field, paving the way for the introduction of novel technologies in the field of animal POC diagnostics to further optimize livestock biosecurity. 相似文献
20.
Anna Suchankova Margarita Stampelou Klontiana Koutsouki Athanasios Pousias Lakshiv Dhingra Kerry Barkan Nicole Pouli Panagiotis Marakos Roxane Tenta Antonios Kolocouris Nikolaos Lougiakis Graham Ladds 《ACS medicinal chemistry letters》2022,13(6):923
Here we describe the design and synthesis of pyrazolo[3,4-d]pyridazines as adenosine receptor (AR) ligands. We demonstrate that the introduction of a 3-phenyl group, together with a 7-benzylamino and 1-methyl group at the pyrazolopyridazine scaffold, generated the antagonist compound 10b, which displayed 21 nM affinity and a residence time of ∼60 min, for the human A1R, 55 nM affinity and a residence time of ∼73 min, for the human A3R and 1.7 μΜ affinity for the human A2BR while not being toxic. Strikingly, the 2-methyl analog of 10b, 15b, had no significant affinity. Docking calculations and molecular dynamics simulations of the ligands inside the orthosteric binding area suggested that the 2-methyl group in 15b hinders the formation of hydrogen bonding interactions with N6.55 which are considered critical for the stabilization inside the orthosteric binding cavity. We, therefore, demonstrate that 10a is a novel scaffold for the development of high affinity AR ligands. From the mutagenesis experiments the biggest effect was observed for the Y2717.46A mutation which caused an ∼10-fold reduction in the binding affinity of 10b. 相似文献