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Transmission and clinical features of enterovirus 71 infections in household contacts in Taiwan 总被引:6,自引:0,他引:6
Chang LY Tsao KC Hsia SH Shih SR Huang CG Chan WK Hsu KH Fang TY Huang YC Lin TY 《JAMA》2004,291(2):222-227
Context Although enterovirus 71 has caused epidemics associated with significant morbidity and mortality, its transmission has not been thoroughly investigated. Objectives To investigate enterovirus 71 transmission and determine clinical outcomes within households. Design, Setting, and Participants Prospective family cohort study to investigate patients at a children's hospital in Taiwan and family members of these patients who had signs and symptoms suggestive of enterovirus 71 between February 2001 and August 2002. Patients and household members underwent clinical evaluations, virological studies, questionnaire-based interviews, and were followed up for 6 months. Main Outcome Measures Enterovirus 71 infection, defined as a positive viral culture from a throat or rectal swab, or the presence of IgM or a 4-fold increase in neutralizing antibody in serum; and clinical syndromes, defined as asymptomatic; uncomplicated symptomatic; and complicated; with unfavorable outcomes of sequelae or death. Results Ninety-four families (433 family members) had at least 1 family member with evidence of enterovirus 71 infection. The overall enterovirus 71 transmission rate to household contacts was 52% (176/339 household contacts). Transmission rates were 84% for siblings (70/83); 83%, cousins (19/23); 41%, parents (72/175); 28%, grandparents (10/36); and 26%, uncles and aunts (5/19). Of 183 infected children, 11 (6%) were asymptomatic and 133 (73%) had uncomplicated illnesses (hand, foot, and mouth disease, herpangina, nonspecific febrile illness, upper respiratory tract infection, enteritis, or viral exanthema). Twenty-one percent (39/183) experienced complicated syndromes including the central nervous system or cardiopulmonary failure. During the 6-month follow-up, 10 died and 13 had long-term sequelae consisting of dysfunction in swallowing, cranial nerve palsies, central hypoventilation, or limb weakness and atrophy. Age younger than 3 years was the most significant factor associated with an unfavorable outcome in children (P = .004). Among 87 infected adults, 46 (53%) were asymptomatic, 34 (39%) had nonspecific illnesses of fever, sore throat, or gastrointestinal discomfort, and 7 (8%) had hand, foot, and mouth disease. There were no complicated cases in adults. Conclusions Enterovirus 71 household transmission rates were high for children in Taiwan and severe disease with serious complications, sequelae, and death occurred frequently. In contrast, adults had a much lower rate of acquisition of the infection and much less adverse sequelae. 相似文献
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PURPOSE: A previous study has shown that the pulsatile ocular blood flow (POBF) in eyes with asymmetric age-related macular degeneration (AMD) differs. Whereas eyes with drusen have higher POBF than contralateral eyes with disciform scarring, the POBF of eyes with drusen is lower relative to contralateral eyes with choroidal neovascularization (CNV). This study was designed to assess whether the POBF of eyes with CNV changes after transpupillary thermotherapy (TTT), using the contralateral eyes with drusen or scarring without TTT as controls. METHODS: In total, 26 patients with CNV in one eye and drusen or scarring in the other were enrolled in this prospective case series. Eyes with CNV were treated with TTT. POBF was measured monthly in both eyes of each subject. RESULTS: Before TTT, the POBF of eyes with CNV was 1179+/-317 microl/min. After TTT, the POBF of CNV eyes had decreased at 1 month (1015+/-273 microl/min, P=0.002) and 2 months (945+/-398 microl/min, P=0.011) of follow-up, but had rebounded at 3 months (P=0.441) and 6 months (P=0.084). CONCLUSIONS: These findings suggest that TTT decreases the pulsatile choroidal blood flow in eyes with CNV in patients with asymmetric AMD and the effects persist for 2 months. POBF may be used as a modality to monitor the therapeutic effects of CNV in asymmetric exudative AMD. 相似文献
996.
Acacetin inhibits the proliferation of Hep G2 by blocking cell cycle progression and inducing apoptosis 总被引:4,自引:0,他引:4
Flavonoids are a broadly distributed class of plant pigments, universally present in vascular plants and responsible for much of the coloring in nature. They are strong antioxidants that occur naturally in foods and can inhibit carcinogenesis in rodents. In this study, we examined acacetin (5,7-dihydroxy-4'-methoxyflavone), a flavonoid compound, for its effect on proliferation in a human liver cancer cell line, Hep G2. The results showed that acacetin inhibited the proliferation of Hep G2 by inducing apoptosis and blocking cell cycle progression in the G1 phase. Enzyme-linked immunosorbent assay showed that acacetin significantly increased the expression of p53 and p21/WAF1 protein, contributing to cell cycle arrest. An enhancement in Fas/APO-1 and its two form ligands, membrane-bound Fas ligand and soluble Fas ligand, as well as Bax protein, was responsible for the apoptotic effect induced by acacetin. Taken together, our study suggests that the induction of p53 and activity of the Fas/Fas ligand apoptotic system may participate in the antiproliferative activity of acacetin in Hep G2 cells. 相似文献
997.
Trigeminal neuralgia is a disorder of paroxysmal and severely disabling facial pain and continues to be a real therapeutic challenge to the clinicians. While the exact cause and pathology of this disorder is uncertain, it is thought that trigeminal neuralgia caused by irritation of the trigeminal nerve. This irritation results from damage due to the change in the blood vessels, the presence of a tumor or other lesions that cause the compression of the trigeminal root. The pain of trigeminal neuralgia is characterized by unilateral pain attacks that start abruptly and last for varying periods of time from minutes to hours. The quality of pain is usually sharp, stabbing, lancinating, and burning. The attacks are initiated by mild stimuli such as light touch of the skin, eating, chewing, washing the face, brushing the teeth, and exposure to wind. Although antiepileptic drug therapy may be beneficial in the treatment of trigeminal neuralgia, up to one-half of the patients become refractory or intolerant to these medications. At present there are few other effective drugs. In cases of lacking effect after pharmacotherapy, surgical options may be considered. Currently there is growing amount of evidence to suggest that the psychoactive ingredient in cannabis and individual cannabinoids may be effective in alleviating neuropathic pain and hyperalgesia. Evidence suggests that cannabinoids may prove useful in pain modulation by inhibiting neuronal transmission in pain pathways. Considering the pronounced antinociceptive effects produced by cannabinoids, they may be a promising therapeutic approach for the clinical management of trigeminal neuralgia. 相似文献
998.
Pardo FS Hsu DW Zeheb R Efird JT Okunieff PG Malkin DM 《British journal of cancer》2004,91(9):1678-1686
Abnormalities of the p53 tumor-suppressor gene are found in a significant proportion of astrocytic brain tumours. We studied tumour specimens from 74 patients evaluated over 20 years at the Massachusetts General Hospital, where clinical outcome could be determined and sufficient pathologic material was available for immunostaining. p53 expression studies employed an affinity-purified p53 monoclonal antibody, whose specificity was verified in absorption studies and, in a minority of cases, a second antibody recognising a different epitope of p53. Significant overexpression of p53 protein was found in 48% of the 74 tumours included in this series and high levels of expression were associated with higher mortality from astrocytic tumours (P<0.001, log rank). Multivariate analyses revealed that immunohistochemically detected p53 was an independent marker of shortened progression-free and overall actuarial survival in patients with astrocytic tumours, suggesting that increased expression of p53 plays an important role in the pathobiology of these tumours. In a subset of 36 cases, coding regions of the p53 gene were completely sequenced via SSCP and direct DNA sequencing, revealing that overexpression of p53 protein is not always associated with point mutations in conserved exons of the p53 gene. Finally, we confirmed p53 protein expression in early-passage human glioma cell lines of known p53 mutational status and immunostaining scores. Although grade continues to be the strongest prognostic variable, the use of p53 staining as a prognostic indicator, in contrast to mutational DNA analyses, may be a useful adjunct in identifying patients at higher risk of treatment failure. 相似文献
999.
Selective growth inhibition of tumor cells by a novel histone deacetylase inhibitor, NVP-LAQ824 总被引:8,自引:0,他引:8
1000.
Induction of unresponsiveness limits tumor protection by adoptively transferred MDM2-specific cytotoxic T lymphocytes 总被引:2,自引:0,他引:2
Bendle GM Holler A Pang LK Hsu S Krampera M Simpson E Stauss HJ 《Cancer research》2004,64(21):8052-8056
There is evidence showing that high avidity CTLs can be more effective than low avidity CTLs for adoptive tumor immunotherapy. Because many T cell-recognized tumor antigens are nonmutated self-proteins, tolerance mechanisms are likely to render high avidity T cells unresponsive or cause T cell elimination by clonal deletion. We recently used the allo-restricted strategy to circumvent immunologic tolerance to a ubiquitously expressed tumor-associated protein, MDM2, and raised high avidity CTLs in humans and in mice. In this study, we investigated whether high avidity MDM2-specific CTLs can mediate tumor protection without causing damage to normal tissues in mice. Although the CTLs prolonged survival of tumor-bearing mice without causing damage to normal tissues, tumor protection was incomplete. We show that tumor growth occurred despite the continued presence of MDM2-specific CTLs and the continued susceptibility of tumor cells to CTL killing. However, analysis of the CTLs revealed that they had been rendered unresponsive in vivo because they did not produce interferon gamma in response to antigen-specific stimulation. These experiments suggest that induction of unresponsiveness may be an important mechanism limiting the efficacy of adoptive CTL therapy. 相似文献