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81.
Summary An outbreak of acute hemorrhagic conjunctivitis (AHC) was reported in Singapore military camps in the year 2005. A total of
103 conjunctival swab specimens were collected from military personnel diagnosed clinically with AHC. PCR testing on these
conjunctival specimens revealed the presence of an enterovirus, and this was confirmed by virus isolation. Molecular typing
using a partial VP1 gene confirmed a variant of coxsackievirus A24 (CA24v) as the most likely etiological agent for the outbreak.
Full-length genome sequencing was carried out on 2 selected virus strains, DSO-26SIN05 and DSO-52SIN05. Sequence comparison
and phylogenetic analyses of the VP4, VP1 and 3Cpro gene regions were performed, clustering the Singapore CA24v strains with
viruses originating from Asia in the post-2000 era. In addition, we report evolution rates of 4.2 × 10−3 and 1.0 × 10−3 nucleotide/year, respectively, for the VP4 capsid and 3Cpro gene regions. Our result shows a focal evolutionary point around
1965–1966, suggesting that the CA24v virus has been evolving constantly since its emergence in Singapore, nearly 40 years
ago. 相似文献
82.
Wang B Lau KA Ong LY Shah M Steain MC Foley B Dwyer DE Chew CB Kamarulzaman A Ng KP Saksena NK 《Virology》2007,367(2):288-297
83.
Barrett JW Shun Chang C Wang G Werden SJ Shao Z Barrett C Gao X Belsito TA Villenevue D McFadden G 《Virology》2007,361(1):123-132
The myxoma virus M063R gene product exhibits some sequence similarity to the poxvirus host range gene, C7L, of vaccinia virus. To address the potential host range function of the M063R gene product in rabbits, a deletion mutant of myxoma virus (vMyx63KO) was generated and characterized. vMyx63KO replicated to normal titre levels and produced foci that were indistinguishable from those produced by MV in vitro in a monkey kidney cell line (BGMK) that are permissive for wild type MV. However, vMyx63KO failed to replicate in all rabbit cell lines tested, including both primary and established cells lines, as well as cells derived from a variety of tissues. M063R expression was not required for myxoma virus binding, entry or early gene expression, whereas DNA replication was aborted and late genes were not expressed in vMyx63KO infected rabbit cells. Thus, the replication block for vMyx63KO in rabbit cells preceded the stage of late gene expression and DNA replication. Finally, an in vivo pathogenesis study indicated that vMyx63KO failed to cause any signs of classic myxomatosis in infected rabbits, but functioned as a non-replicating vaccine and provided protection for subsequent challenge by wild type myxoma virus. Altogether, these observations demonstrate that M063R plays a critical role in determining the host specificity of myxoma virus in rabbit cells. 相似文献
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86.
Over an average span of one year, we performed a prospective clinical and immunologic evaluation of 30 patients with hemophilia. No patient developed life-threatening opportunistic infection or malignancy; however, the immunologic abnormalities and lymphadenopathy initially present in nine patients (lymphadenopathy group) persisted. In addition, five patients, representing 24% of the initial group without lymphadenopathy, developed generalized lymphadenopathy (converter group). One episode of idiopathic thrombocytopenia (ITP) and one episode of staphylococcal sepsis occurred in this "converter" group; one episode of ITP also occurred in the lymphadenopathy group. Sixteen patients remained asymptomatic. At the time of the follow-up evaluation, those differences in mononuclear cell (MNC) percentages and numbers noted initially among the three hemophiliac groups were no longer present. Natural killer cell function alone or in the presence of biologic response modifiers was not different among hemophiliac and control groups. Before developing lymphadenopathy, the converter group of patients had significantly better lymphocyte mitogenic function than did the other two groups of patients with hemophilia. However, lymphocyte mitogenic responses of all groups of patients with hemophilia significantly deteriorated over the course of the study. The abnormal mitogenic responses noted in these patients was explained in part by higher levels of spontaneous suppressor cell activity in mononuclear cell preparations from patients with hemophilia. We conclude that long-term immunologic studies of this patient population requires both quantitative and qualitative evaluations. Our data show that patients with hemophilia have progressive dysfunction of cell- mediated immunity. 相似文献
87.
In vitro characterization of the human recombinant soluble granulocyte- macrophage colony-stimulating factor receptor 总被引:1,自引:0,他引:1
We have cloned, expressed, and partially purified a naturally occurring, truncated, soluble form of the human granulocyte-macrophage colony-stimulating factor (GM-CSF) receptor alpha subunit to investigate its biochemical and biologic properties. The soluble receptor species lacks the transmembrane and cytoplasmic domains that are presumably removed from the intact receptor cDNA by a mechanism of alternative splicing. The resulting soluble 55- to 60-kD glycosylated receptor species binds GM-CSF with a dissociation constant (kd) of 3.8 nmol/L. The soluble GM-CSF receptor successfully competes for GM-CSF binding not only with the transmembrane-anchored GM-CSF receptor alpha subunit but also with the native oligomeric high-affinity receptor complex. In addition, in human bone marrow colony-forming assays, the soluble GM-CSF receptor species can antagonize the activity of GM-CSF. Our data suggest that the soluble GM-CSF receptor may be capable of acting in vivo as a modulator of the biologic activity of GM-CSF. 相似文献
88.
Hong Chew Pratap Shetty Maqsood Elahi Zakir Akhunji 《General thoracic and cardiovascular surgery》2014,62(6):386-389
Chylous pericardial effusion is an uncommon entity that is most commonly associated with post-cardiac surgery, in particular aortic valve and minimally invasive cardiac surgery. Post-radiation therapy, infection, mediastinal neoplasm, lymphoma and a small group of idiopathic, spontaneous chylous pericardial effusion have also been reported as the causes. Here, we report a rare case of pericardial effusion secondary to chylous fistula in a 63-year-old man with Poland syndrome. The case highlights an unusual thoracic duct anomaly as a cause of our reported chylous pericardial effusion. 相似文献
89.
Bridget D. Mathison Lindsey L. Kimble Kerrie L. Kaspar Christina Khoo Boon P. Chew 《Nutrition Research》2014
Consumption of polyphenol-rich foods is associated with lower risk from many chronic diseases. We hypothesized that a single dose of cranberry beverage would improve indices of oxidative stress, inflammation, and urinary antibacterial adhesion activity in healthy humans. Six males and 6 females (18-35 years; body mass index, 19-25 kg/m2) consumed placebo, cranberry leaf extract beverage, or low-calorie cranberry juice cocktail (LCJC) once in a randomized, double-blind, placebo-controlled cross-over experimental design trial. The washout period between beverages was 1 week. Blood was collected 0, 2, 4, 8, and 24 hours after beverage consumption for measuring oxidative and inflammatory biomarkers. Urine was collected at 0, 0 to 3, 3 to 6, 6 to 9, 9 to 12, and 24 hours postintervention to assess antibacterial adhesion activity. Consumption of cranberry leaf extract beverage elevated (P < .05) blood glutathione peroxidase activity, whereas LCJC consumption increased (P < .05) glutathione concentrations and superoxide dismutase activity compared with placebo. Cranberry leaf extract beverage and LCJC consumption had no effect on the inflammatory biomarkers measured as compared with placebo. At 0 to 3 hours postconsumption, urine from participants who consumed cranberry beverages had higher (P < .05) ex vivo antiadhesion activity against P-fimbriated Escherichia coli compared with placebo. An acute dose of cranberry beverages improved biomarkers of antioxidant status and inhibition of bacterial adhesion in urine. 相似文献
90.