Biomedical subjects

Wei-Li Chen

Publications and source records attributed to Wei-Li Chen.

6 recordsLinked to original sources

PubMed2003

Ribavirin or CpG DNA sequence-modulated dendritic cells decrease the IgE level and airway inflammation.

Asthma is an allergic disease that is characterized by the imbalance between Th1 and Th2 cells and by the predominant Th2-type immune response. In this study, we investigated the application of dendritic cell (DCs)-based immunotherapy in modulating the immune response of allergic diseases. DCs incubated with ovalbumin (OVA), OVA plus ribavirin, OVA plus CpG-oligodeoxynucleotides (ODN 1826), or OVA plus non-CpG-ODN (ODN 1745) for 48 hours were injected intravenously into four corresponding groups of BALB/c mice. All of the mice were then immunized with OVA intraperitoneally 7 days later to establish an animal model of asthma. Serum levels of OVA antibody, airway hyperresponsivness, cell composition and cytokine levels in the bronchoalveolar lavage fluid, and cytokine profiles of spleen cells were analyzed. The data showed that ribavirin and ODN 1826 increased interleukin-12 synthesis and inhibited interleukin-10 production. ODN 1826 could also enhance the expression of B7.1, B7.2, major histocompatibility complex I, and major histocompatibility complex II molecules. Furthermore, the DCs modulated by ribavirin and ODN 1826 could downregulate the Th2-type immune response in vivo and could alleviate airway inflammation. This study elucidated the effect of ribavirin and CpG-ODN on DCs and demonstrated that in vitro modulated DCs might be a potential therapeutic approach for asthma.

Adjuvants, Immunologic↗

PubMed2002

Radiation surveys and dose equivalent assessments for 60Co-contaminated rebar buildings.

The first 60Co-contaminated rebar building was found in Taipei City in 1992. In order to provide effective remedial suggestions to the building owner and residents of contaminated housing units, and to evaluate the dose equivalent to the residents, the Atomic Energy Council (AEC) organized a survey team on October 17, 1992. The main object of this team was to perform a detailed survey and dose equivalent evaluation of the 60Co-contaminated buildings. By the end of 2000, 181 buildings with 1607 housing units were identified as being contaminated with radioactive rebars at different levels. This article presents the detailed radiation survey and dose equivalent evaluation procedures employed by the survey team.

Air Pollution, Indoor↗

PubMed2002

Health examination and chromosome aberration analysis of residents living in 60Co-contaminated rebar buildings.

PURPOSE: To elucidate the results of health examination and chromosome aberration analysis of residents living in (60)Co-contaminated rebar buildings. MATERIAL AND METHODS: Medical surveillance including peripheral blood analysis, urine analysis, chest X-ray, blood biochemical analysis, electrocardiography, thyroid function test and physical examination was performed on 189 residents within 6 months after disclosure of radiation exposure. The annual dose for this group of residents varied from 2 to 95 mSv year(-1) (mean+/-1 SD = 18+/-21 mSv year(-1)) above the background exposure of the Taiwanese population. For chromosome analysis, 500-671 lymphocytes were scored for 136 residents, and the numbers of dicentrics and rings were counted and analysed. RESULTS: Medical surveillance showed that the most frequent abnormalities were elevation of the erythrocyte sedimentation rate occurring in 14.8% of those examined. Reduction of the negative charge on erthrocytes by ionizing radiation may cause an elevation of erythrocyte sedimentation rate. Statistical analysis of chromosome aberration data showed that the mean dicentric frequency for radiation-contaminated building residents (0.69+/-0.93 SD) was significantly higher than those for controls (0.33+/-0.49) (p <0.01). CONCLUSIONS: No radiation effects were found in the preliminary health examination. However, lymphocyte chromosome analysis of the radiation-contaminated building residents showed that prolonged low-dose-rate gamma exposure induced cytogenetic changes in humans.

Adolescent↗

PubMed2002

Ciliary detachment after pars plana vitrectomy: an ultrasound biomicroscopic study.

PURPOSE: To determine the incidence, duration, risk factors, and clinical outcomes for ciliary detachment after pars plana vitrectomy (PPV). METHODS: A total of 109 eyes of 103 patients who underwent PPV for various disease entities were included. Ultrasound biomicroscopy was applied to determine the tomographic features of the ciliary body before and 1, 3, and 7 days after the surgery. All eyes were then examined once weekly for 2 months. Demographic, preoperative, intraoperative, and postoperative parameters were evaluated to assess their predictive value in the formation of postvitrectomy ciliary detachment. RESULTS: Ciliary detachment was observed in 46 eyes (42%) after surgery and persisted for less than 3 weeks in 40 of 46 eyes. It most frequently occurred in eyes of patients with proliferative diabetic retinopathy (PDR) (64%) or retinal vascular obstructive diseases (RVO) (47%). Extensive retinal photocoagulation and retinal cryopexy positively predisposed to its formation whereas fluid-gas exchange had a protective effect. No clinical complications were observed in eyes with postoperative ciliary detachment. CONCLUSION: Ciliary detachment occurred frequently after PPV. A diagnosis of PDR or RVO and surgical procedures with extensive retinal photocoagulation and retinal cryopexy may have a higher incidence of its occurrence.

Adolescent↗

PubMed2002

Ultrasound biomicroscopic findings in rabbit eyes undergoing scleral suction during lamellar refractive surgery.

PURPOSE: To evaluate changes of the central anterior chamber depth, cilio-angular cross-sectional surface area, and intraocular pressure in rabbit eyes undergoing application of the scleral suction ring during lamellar refractive surgery. METHODS: Thirty eyes of 30 rabbits were used in the study. The eyes were assigned to one of the following five surgical groups: group 1, no application of the suction ring; group 2, suction for 2 minutes; group 3, suction for 1 minute; group 4, suction for 20 seconds; and group 5, suction for 10 seconds. Ultrasound biomicroscopy (UBM) was performed to determine tomographic features, including central anterior chamber depth, cross-sectional surface area of the ciliary body, and chamber angle structure before and 10 minutes, 1 hour, 2 hours, 1 day, 2 days, 1 week, and 2 weeks after surgery. Intraocular pressure was also measured at each of these time points. RESULTS: Swelling of the ciliary body occurred in groups 2 to 5 of eyes from 10 minutes up to 1 day after the operation, and its severity was positively related to the duration of suction. Shallowness of the chamber angle was positively related to swelling. All UBM-detectable changes became insignificant compared with baseline values at 2 days after the operation. No significant change was found in the central anterior chamber depth and intraocular pressure during the 2-week postoperative observation period. CONCLUSIONS: Transient change in the ciliary body and the chamber angle occurred frequently after application of the scleral suction ring during lamellar refractive surgery in rabbit eyes. Its severity was positively related to the duration of suction. Swelling of the ciliary body corresponded with the shallowness of the chamber angle without alteration of the corneal-lenticular distance and intraocular pressure.

Animals↗

PubMedDate not supplied

Comparison of subjective visual acuity with visual acuity predicted from C-scan topography.

PURPOSE: To compare the capability of objective measures of visual acuity (potential visual acuity from C-scan) to predict subjective visual acuity (best spectacle-corrected visual acuity [BSCVA]). METHODS: Patients with BSCVA > or = 20/20 were enrolled in four groups (Group 1: normal [33 eyes]; Group 2: < -7.00 D myopia [43 eyes]; Group 3: > or = -7.00 D myopia [28 eyes]; Group 4: At least 1 month after LASIK [93 eyes]). Videokeratography was performed with the ray tracing Technomed C-scan. The potential visual acuity from C-scan was obtained with pupils undilated and intact precorneal tear films. All visual acuity was recorded in logMAR, and the significance of differences between acuities was assessed with a one-way ANOVA test. RESULTS: The potential visual acuity from C-scan ray tracing of normal and myopic eyes in response to both photopic and mesopic stimuli did not differ. In a given eye, the potential visual acuity from C-scan ray tracing was better than BSCVA, and the difference was statistically significant. Although the potential visual acuity from C-scan of postoperative LASIK eyes in response to photopic stimuli was the same, it decreased under mesopic conditions. CONCLUSIONS: Potential visual acuity from C-scan overestimates subjective visual acuity due to the inadequate assumptions in ray tracing or individual retinal resolution ability. In addition, the potential visual acuity from C-scan ray tracing varies with pupil diameter in different illumination.

Adolescent↗