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981.
Expansion of quasispecies diversity but no evidence for adaptive evolution of SHIV during rapid serial transfers among seronegative macaques 总被引:5,自引:0,他引:5
Four successive, rapid serial passages of the nonpathogenic, CCR5-tropic simian-human immunodeficiency virus SHIV(SF162) in rhesus macaques resulted in an increase in acute plasma viremia with each passage and the emergence of a pathogenic isolate SHIV(SF162P3) in one of the passage three transfer animals (macaque T353). To explore the mechanism(s) underlying increased virulence of SHIV(SF162) upon in vivo passage, the evolution of the HIV-1 envelope gene was characterized in plasma and PBMC samples obtained from animals before (week 1) and after (week 3) the time of virus transfer. We found no evidence in support of adaptive evolution of the HIV gp120 during rapid serial passage; however, the animals which later received passage virus had more diverse quasispecies. SHIV(SF162P3)-like gp120 sequences were first detected in macaque T353 at week 6, after seroconversion. These sequence changes increased in frequency and number at later time points. The first sequence change conferred neutralization escape but not an increase in viral infectivity that could account for the apparent increase in replicative capacity of the later passage viruses. Collectively, our data argue against any host-specific adaptation of the HIV-1 envelope gp120 as the basis for the generation of more aggressive SHIV variants during rapid serial transfers in seronegative macaques, and support the model of quasispecies diversity as a predictor of pathogenesis. Envelope sequence changes accumulate principally in response to immune pressure exerted by the host, generating viral variants that can persist in the presence of a strong host immune response. 相似文献
982.
Hsu CH Lin SS Liu FL Su WC Yeh SD 《The Journal of allergy and clinical immunology》2004,113(6):268-1085
BACKGROUND: Sublingual-swallow immunotherapy in house dust mite-related asthma has a good safety profile and improves respiratory function and bronchial hyperreactivity. Zucchini yellow mosaic virus (ZYMV) is envisaged as a promising viral vector for expressing large quantity of foreign proteins in cucurbit species. OBJECTIVE: We sought to investigate whether oral feeding of dust mite allergen expressed by ZYMV in a cucurbit species can suppress allergen-induced inflammation and IgE synthesis. METHODS: An infectious plant virus clone, p35SZYMV2-26, that contains the full-length cDNA to the genomic RNA of a Taiwan isolate of ZYMV, driven by the cauliflower mosaic virus 35S promoter, was engineered as an in vivo viral vector to express Dermatophagoides pteronyssinus group 5 allergen (Der p 5) in cucurbit species. Female BALB/c mice were intraperitoneally sensitized with Escherichia coli bacteria-expressed Der p 5 and orally treated with the virus-expressed Der p 5 (vDer p 5) extracted from the recombinant virus-infected squash plants. Der p 5-specific immunoglobulins were measured by ELISA, and bronchoalveolar lavage assays were used to measure airway inflammation. RESULTS: Infectivity assays and immunoblotting revealed that large quantities of free-form vDer p 5 are produced in the recombinant virus-infected squash plants. The recombinant virus carried and expressed the Der p 5 allergen in squash plants for at least 1 year after numerous passages. In animal tests, squash extract containing vDer p 5 inhibited Der p 5-specific IgE synthesis and airway inflammation. CONCLUSION: Our results suggest that oral feeding with allergen produced by the plant viral vector provides a novel approach for the therapy of allergic asthma. 相似文献
983.
Chang YC Hsu TL Lin HH Chio CC Chiu AW Chen NJ Lin CH Hsieh SL 《Journal of leukocyte biology》2004,75(3):486-494
Decoy receptor 3 (DcR3) is a soluble receptor of the tumor necrosis factor receptor superfamily and is readily detected in certain cancer patients. Recently, we demonstrated that DcR3.Fc-treated dendritic cells skew T cell responses to a T helper cell type 2 phenotype. In this study, we further asked its ability to modulate CD14+ monocyte differentiation into macrophages induced by macrophage-colony stimulating factor in vitro. We found that DcR3.Fc was able to modulate the expression of several macrophage markers, including CD14, CD16, CD64, and human leukocyte antigen-DR. In contrast, the expression of CD11c, CD36, CD68, and CD206 (mannose receptor) was not affected in the in vitro culture system. Moreover, phagocytic activity toward immune complexes and apoptotic bodies as well as the production of free radicals and proinflammatory cytokines in response to lipopolysaccharide were impaired in DcR3.Fc-treated monocyte-derived macrophages. This suggests that DcR3.Fc might have potent, suppressive effects to down-regulate the host-immune system. 相似文献
984.
Li CC Qian ZR Hirokawa M Sano T Pan CC Hsu CY Yang AH Chiang H 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2004,112(6):390-398
Female adnexal tumor of probable Wolffian origin (FATWO) is a rare entity which is believed to originate from mesonephric (Wolffian) remnants on the basis of its location where the remnants are abundant. Its behavior is usually indolent, although some cases can recur or metastasize. The authors present the clinicopathological features of two cases of FATWO arising in the broad ligament, and focus on the expression of adhesion molecules and proliferative marker. Mesonephric duct remnants are also examined in an attempt to elucidate the histogenesis of FATWOs. The two FATWOs were well-circumscribed solid masses arising in the leaves of the broad ligament and histological examination revealed a mixture of cysts and tubules imparting a sieve-like pattern and mucin-negative eosinophilic secretion within these tubules. Immunohistochemically, the tumors showed the expression of cytokeratin 7 and 20, high-molecular-weight cytokeratin, and calretinin, which closely resembled that of the mesonephric duct remnants. Regarding CK 20, CD 10, EMA, S-100 protein, and vimentin their expression was in part not identical with previous studies. E-cadherin, alpha and beta-catenin were strongly expressed along the cell membrane of the tumor cells. The Ki-67 labeling index of FATWO was 0% and 3.2% in each case. The preservation of the E-cadherin-catenin complex and low Ki-67 labeling index could explain the indolent behavior and low malignant potential of this tumor. 相似文献
985.
Based on granular computing methodology, we propose two criteria to quantitatively measure privacy invasion. The total cost criterion measures the effort needed for a data recipient to find private information. The average benefit criterion measures the benefit a data recipient obtains when he received the released data. These two criteria remedy the inadequacy of the deterministic privacy formulation proposed in Proceedings of Asia Pacific Medical Informatics Conference, 2000; Int J Med Inform 2003;71:17-23. Granular computing methodology provides a unified framework for these quantitative measurements and previous bin size and logical approaches. These two new criteria are implemented in a prototype system Cellsecu 2.0. Preliminary system performance evaluation is conducted and reviewed. 相似文献
986.
Association analysis between Tourette's syndrome and dopamine D1 receptor gene in Taiwanese children
OBJECTIVE: Recent research suggests that Tourette's syndrome (TS) may result from a defect in the dopamine system. The dopamine 1 receptor (DRD1) gene is a candidate gene in the study of the etiology of neuropsychiatric diseases that may involve dopaminergic abnormalities. We sought to test the hypothesis that the DRD1 gene might play a role in TS. METHODS: By performing an association study, we collected an independent sample of patients from the midland region of Taiwan and investigated whether DRD1 gene polymorphisms can be used as markers of susceptibility to TS. A total of 148 children with TS and 83 normal control subjects were included in the study. A polymerase chain reaction was used to identify the A/G polymorphism of the DRD1 gene. Genotypes and allelic frequencies for the DRD1 gene polymorphisms in both groups were compared. RESULTS: The results showed that genotypes and allelic frequencies for the DRD1 gene polymorphisms in both groups were not significantly different. CONCLUSION: These data suggest that DRD1 gene may not be a useful marker for prediction of the susceptibility of TS. 相似文献
987.
Liu TC Hsu CJ Hwang JH Tseng FY Chen YS 《ORL; journal for oto-rhino-laryngology and its related specialties》2004,66(3):124-129
The purpose of this study was to investigate the effects of concomitant exposure to noise and alcohol on the auditory thresholds. Twenty-four guinea pigs were equally divided into three groups: the acute intoxication group, the chronic intoxication group and the control group. Animals in the acute group received single intraperitoneal injections of ethanol (2 g/kg). In the chronic group, alcohol was administered via drinking water (10%, v/v) over a 60-day period. All animals were exposed to a white noise at the intensity of 105 dB A for 30 min. Auditory brainstem response (ABR) thresholds and distortion product otoacoustic emission (DPOAE) levels were measured before, immediately after noise exposure and also 1, 2, and 7 days following exposure. The results showed: first, acute alcohol injection caused a significant, temporary elevation of ABR threshold (4.8 dB in average), while chronic alcohol treatment did not change auditory threshold significantly. Second, noise exposure induced a mean threshold shift of 15.4- 19.7 dB. ABR threshold returned to normal 2 days after exposure. Both acute and chronic alcohol treatment did not alter the magnitude and time course of recovery of the temporary threshold shift (TTS). Third, the mean DPOAE amplitudes decreased at most frequencies following acute injection of alcohol. However, the differences did not reach statistical significance. Fourth, the mean DPOAE levels dropped 3.4-9.6 dB in all groups after noise exposure and returned to normal 1 day to 2 days after noise. There were no significant differences in the amount of DPOAE suppression after noise between the three groups. In summary, we have found that acute and chronic treatment of alcohol in combination with noise did not significantly exacerbate TTS or decrease DPOAE amplitudes relative to noise exposure alone. 相似文献
988.
Shou-Jen?Wang Wei-Chung?Hsu Yi-Ho?YoungEmail author 《European archives of oto-rhino-laryngology》2004,261(5):247-250
Primary jugular foramen (JF) tumor, such as glomus jugular tumor or JF schwannoma, may manifest as a lower cranial nerve deficit; in addition, it can be accompanied by deafness or vertigo if it affects the cranial nerve (CN) VIII. Recently, we encountered JF schwannoma 1 and glomus jugulare tumor 1. Both cases invaded the adjacent cerebellopontine angle, leading to cochleo-vestibular deficits prior to the operation. After surgery, recovery of the audiovestibular function, including hearing, auditory brainstem response and caloric response, was anticipated in both patients. Therefore, cochleo-vestibular deficits in JF tumors can be attributed to compression neuropathy, rather than tumor infiltration. 相似文献
989.
990.
Fu YC Chi CS Chiu YT Hsu SL Hwang B Jan SL Chen PY Huang FL Chang Y 《Archives of disease in childhood》2004,89(4):368-373
Background: Epidemics of enterovirus 71 infection have caused the death of many children throughout the world. Rhombencephalitis, brain stem encephalitis, and heart failure were present in all of the fatal cases. However, no evidence of myocarditis was noted in the heart specimens, and the mechanism of heart failure remains unknown. Aims: To characterise the presentation of cardiac complications in children with enterovirus rhombencephalitis and discuss its pathogenesis. Methods: Ninety one consecutive patients with enterovirus rhombencephalitis underwent echocardiography. Of these, 17 patients (nine male, eight female; median age 14 months, range 4–57 months) with left ventricular dysfunction were studied. Results: Tachycardia was noted in all patients and systemic hypertension in 12. Muscle-brain fraction of creatine kinase was >5% in 14 patients. Plasma norepinephrine and epinephrine levels were significantly raised in the three patients in whom these were analysed. Electrocardiographic abnormalities were noted in eight patients. Pulmonary oedema was complicated in 15 patients. The initial ejection fraction of the left ventricle was 22–58% (mean 37%, SD 11%). All patients deteriorated to hypotensive shock within 12 hours and 13 died. Heart specimens from seven patients showed no evidence of myocarditis, but significant coagulative myocytolysis, myofibrillar degeneration, and cardiomyocyte apoptosis were observed. Conclusions: Acute heart failure was noted in 19% of patients with enterovirus rhombencephalitis, which had a fatality rate of 77%. It was not caused by myocarditis but possibly by neurogenic cardiac damage. 相似文献