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991.
Induction of specific Th1 responses and suppression of IgE antibody formation by vaccination with plasmid DNA encoding Der f 11 总被引:4,自引:0,他引:4
DNA vaccines encoding low-molecular-weight allergens have been used to prevent IgE responses. A high-molecular-weight mite allergen Der f 11 that was hardly to be purified for immunotherapy was used to develop a DNA vaccine here. Vaccination of mice with plasmid DNA encoding Df11 (pDf11) induced Th1 responses characterized by IgG2a responses and spleen cell secretion of IFN-gamma. In contrast, sensitization with recombinant Der f 11 (rDf11) and alum induced Th2 responses characterized by IgE responses and spleen cell secretion of IL-4 and IL-5. Vaccination with pDf11 prevented the induction of IgE responses. Moreover, it could inhibit on-going IgE responses. The debate whether CD4+ or CD8+ T cells were the regulatory cells to inhibit IgE responses by DNA vaccination was also examined. First, sensitization of pDf11-vaccinated mice after depletion of CD8+ T cells still showed suppression of IgE responses. Secondly, adoptive transfer of either CD4- or CD8-depleted spleen cells from pDf11-vaccinated mice suppressed IgE responses. In conclusion, this is the first report to confirm the therapeutic effect of a DNA vaccine encoding a strong allergen on specific IgE responses. Both CD4+ and CD8+ T cells are crucial for the immunomodulation of IgE responses by pDf11. 相似文献
992.
Yang T Wu TN Hsu SW Lai CH Ko KN Liou SH 《International archives of occupational and environmental health》2002,75(8):528-534
OBJECTIVES: The purpose of this study was to investigate the blood lead levels (BLLs) of primary-school children aged 7 to 12 in Penghu island and to determine the factors affecting their BLLs. METHODS: A total of 1,885 participants were recruited and BLLs were measured with a flameless atomic absorption spectrophotometer. A questionnaire was used to collect personal information. RESULTS: The results indicated that the mean BLL of primary-school children in Penghu was 6.0+/-2.4 microg/dl (1.0 approximately 29.3 microg/dl). The mean BLL of schoolboys ( n=1,046) was 6.3+/-2.6 microg/dl, with a maximum of 29.3 microg/dl, while the mean BLL of schoolgirls ( n=839) was 5.7+/-2.2 microg/dl, with a maximum of 23.4 microg/dl. Risk-factor analysis showed that personal characteristics (i.e., gender, frequency of milk consumption, grade levels) and geographic factors (i.e., levels of urbanization) significantly influence the BLLs. However, there was no significant impact on BLLs from drinking water, residential distance from a major road, and living close to lead-emitting sources. CONCLUSIONS: Geographical factors were highly associated with BLLs. The BLLs of the primary-school children living in the main Penghu island were lower than those in the other small islands. 相似文献
993.
994.
A prospective study regarding the complications of transcatheter intraarterial lipiodol chemoembolization in patients with hepatocellular carcinoma 总被引:16,自引:0,他引:16
BACKGROUND: Hepatocellular carcinoma (HCC) is a common cause of cancer death throughout the world. The majority of patients are not suitable for curative resection either because of the advanced stage of the disease at the time of presentation or because of underlying cirrhosis. Transcatheter intraarterial lipiodol chemoembolization (TACE) has been reported to be one of the most effective palliative measures for HCC. However, its severe side effects continue to make its use controversial. METHODS: In the current study, the authors prospectively evaluated 197 sessions of TACE performed in 59 patients with HCC. RESULTS: Acute hepatic decompensation occurred in 20% of the 197 sessions with 3% of cases being irreversible. Significant elevation of bilirubin was associated with the dosage of cisplatin used (P = 0.0001), basal bilirubin level (P = 0.0001), basal prothrombin time (P =0.004), basal aspartate aminotransferase (AST) level (P = 0.013), and stage of cirrhosis (P < 0.0001). Patients with irreversible hepatic decompensation were more likely to have higher pre-TACE bilirubin levels (P = 0.009), more prolonged prothrombin time (P = 0.015), received a higher dose of cisplatin (P = 0.033), and more advanced cirrhosis (P < 0.0001). The majority of the other side effects were self-limiting with the exception of one patient who died of liver and splenic abscesses. Approximately 36% of the patients achieved a tumor response, 39% achieved stable disease, and 29% developed progressive disease. CONCLUSIONS: The results of the current study identified factors that appeared to predispose patients to irreversible hepatic decompensation after TACE. Despite the high percentage of patients who developed hepatic decompensation after TACE, irreversible damage occurred in only a minority. 相似文献
995.
Liang JT Huang KC Lai HS Lee PH Cheng YM Hsu HC Cheng AL Hsu CH Yeh KH Wang SM Tang C Chang KJ 《International journal of cancer. Journal international du cancer》2002,101(6):519-525
The influence of MSI on treatment outcome of colorectal cancers remains unclear and deserves further investigation. We recruited 244 patients with stage IV sporadic colorectal cancers for our study, based on appropriate eligibility criteria. Patients were nonrandomly allocated to 2 treatment groups of either with or without high-dose 5-FU plus leucovorin chemotherapy (HDFL, 5-FU 2,600 mg/m(2) leucovorin 300 mg/m(2) maximum 500 mg). Each treatment group was further divided into 2 subgroups according to high-frequency MSI (MSI-H) status. MSI-H was defined as the appearance of MSI in at least 2 of the 5 examined chromosomal loci (BAT-25, BAT-26, D5S346, D2S123, D17S250). We compared clinicopathologic parameters, p53 overexpression and overall survival between the groups. In addition, 4 subgroups were identified as follows: MSI-H(+)HDFL(+), n = 35; MSI-H(-)HDFL(+), n = 134; MSI-H(+)HDFL(-), n = 17; MSI-H(-)HDFL(-), n = 58. There was no significant difference of background clinicopathologic data between the HDFL(+) and HDFL(-) treatment groups (p > 0.05). Survival analyses indicated that the patients of subgroup MSI-H(+)HDFL(+) survived significantly longer than those of subgroup MSI-H(-)HDFL(+), with median survival times of 24 (95% CI 20.2-27.9) and 13 (95% CI 11.6-14.4) months, respectively (p = 0.0001, log-rank test). In contrast, in patients without chemotherapy, the prognosis was poor irrespective of MSI status, with median survival times of 7.0 (95% CI 4.6-9.4) and 7.0 (95% CI 6.1-7.9) months in the MSI-H(+)HDFL(-) and MSI-H(-)HDFL(-) subgroups, respectively (p = 0.8205, log-rank test). MSI-H cancers responded significantly better to HDFL (p = 0.001), with a mean response rate of 65.71% (95% CI 49.98-81.44%) in subgroup MSI-H(+)HDFL(+) compared to 35.07% (95% CI 26.99-43.15%) in subgroup MSI-H(-)HDFL(+). There appeared to be no preferential metastatic site where response to HDFL can be predicted based on the MSI status of the primary tumor. Toxicity to HDFL was similarly minimal between MSI-H(+) and MSI-H(-) patients (p > 0.05). Multivariate analysis of all patients further indicated that MSI-H and chemotherapy were independent favorable prognostic parameters (p < 0.05). Thus, the better prognosis of stage IV sporadic colorectal cancers with MSI-H may be associated with better chemosensitivity, rather than lower aggressiveness in biologic behavior. 相似文献
996.
贲门癌高发位点的内镜研究 总被引:25,自引:1,他引:24
目的 观察和研究贲门癌的高发位点及其临床意义。方法 分析417例早期贲门癌和451例中晚期贲门癌,发现贲门癌有高发位点存在后,在高发现场重复内镜普查205例,验证该高发位点的真实性。结果 417例早期贲门癌中的327例(78.4%)和451例中晚期贲门癌中的336例(74.5%),始发部位均在贲门黏膜脊根部,在验证性普查的205例中,发现11例贲门癌,其中9例(81.8%)始发部位也在贲门黏膜脊根部。结论 贲门癌的高发位点在贲门黏膜脊根部,它具有重要的临床意义。 相似文献
997.
998.
Serial public cancer screening in China 总被引:1,自引:0,他引:1
Qin DX Li YF Qi JF Zhang XH Lai SQ Zuo JH Yuan FL Wang GQ 《American journal of clinical oncology》2002,25(5):464-467
Screening of hollow-organ cancers has been carried out for 16 years using the occult blood test. We are currently assessing the result of serial public cancer screening in China. Human cancers can be divided into 3 types: 1) surface cancer (15%), 2) hollow-organ cancer (65%), and 3) deep-seated solid-organ cancer (20%). Through an education program, the general population was taught to self-examine the body surface and to use a self-examination kit to detect any occult blood discharged from the hollow organs. On discovering positive or doubtful results, these subjects were referred to the hospital for a complete clinical checkup. A total of 10,000 people ages 40 to 70 years chosen from the university areas in Beijing were divided in a test group (5,000) and a control group (5,000). This study, which was carried out for 4 years, showed that 79 cancers were discovered in the test group, with an annual cancer detection rate of 482.5/10,000 population and a cancer mortality rate of 36.6/10,000. The control group showed an annual cancer mortality rate of 206/10,000 population. The difference has very marked statistical significance ( p< 0.001). During the same interval, an extensive cancer screening was carried out in the high-incidence areas. The Cancer Institute in Sihui city of Guangdong province discovered, by screening 758 persons in the outpatient department during a 2-year period, 16 cancers with 15 as nasopharyngeal cancer. From 1999 to 2000, another extensive public cancer screening in the high-incidence areas in Jiangsu province discovered 480 cancers from an 80,000 population. Together with the screening test carried out by Qin's self-examination kit before the National Supported Cancer Research Project on a population of 431,000, 1,272 cancers and more than 10,000 precancerous lesions have been detected. The self-examination kit and public cancer screening are highly important in the practice of public cancer screening. 相似文献
999.
Differential expression profiling of head and neck squamous carcinoma: significance in their phenotypic and biological classification 总被引:5,自引:0,他引:5
El-Naggar AK Kim HW Clayman GL Coombes MM Le B Lai S Zhan F Luna MA Hong WK Lee JJ 《Oncogene》2002,21(53):8206-8219
The genetic events associated with the development and progression of head and neck squamous carcinoma (HNSC) are largely unknown. We analysed 12 matched pairs of histologically normal squamous mucosa and tumor specimens from six conventional and six phenotypic variants HNSC to define the differentially expressed genes in these tumors. Parallel expression analysis of 8055 unique genes was performed, and the level of the hybridization signal for each gene was measured after normalization. Hierarchical cluster analysis of the expressed genes showed distinct inter- and intra-tumoral patterns in and between conventional squamous carcinoma and squamous carcinoma variants. We also identified 26 (0.32%) differentially expressed genes that were consistently different between matched pairs of normal and tumor specimens; a selected set of the overexpressed genes was validated using real-time quantitative RT-PCR. The majority of the genes were associated with differentiation and proliferation. Our study defines a set of genes that could form the basis for the construction of limited HNSC targeted expression array and in-depth studies and further highlights gene profile differences that may be useful in pathobiologic classification of HNSC. 相似文献
1000.
Au WY Lie AK Kwong YL Shek TW Hawkins BR Lai KN Tang SC Lo CM Fan ST Liu CL Chan GC Chau EM Chiu SW Liang R 《Leukemia & lymphoma》2002,43(7):1403-1407
Post-transplantation lymphoproliferative disease (PTLD) is an unique iatrogenic complication after bone marrow transplantation (BMT) and solid organ transplantation (SOTx). The pattern of EBV related lymphoma in Chinese is different from Caucasians. We surveyed the incidence, clinical and pathological spectrum of PTLD among 541 cases of allogeneic BMT, 145 cases of renal transplant, 35 cases of heart/lung transplantation and 146 cases of orthotopic liver transplantation (OLT). From 1994 to 2001, 13 consecutive cases of PTLD were diagnosed, ranging from disseminated NK cell lymphoma to localized plasmacytoma. Both donor and recipient derived PTLD was documented. Disease was often heralded by cytomegaloviral disease and antithymocyte globulin (ATG) usage. Two cases were diagnosed post-mortem, and six patients died of PTLD at a median of 3 months. Complete and partial remission was only achieved in 3 and 2 cases, respectively, despite a range of treatment (reduced immunosuppression, explantation, radiotherapy, combination chemotherapy, donor lymphocytes, autologous marrow infusion and rituximab). Most responding patients died subsequently of rejection, infection and graft versus host disease (GVHD). The incidence of PTLD is not increased in Chinese patients. However, some patients may be at increased risk, especially mismatched allogeneic BMT, parental OLT (especially involving young infants) and heavy ATG exposure. 相似文献