Biomedical subjects

Yisheng Zhong

Publications and source records attributed to Yisheng Zhong.

5 recordsLinked to original sources

PubMed2005

Subcellular localization of caspase-3 activation correlates with changes in apoptotic morphology in MOLT-4 leukemia cells exposed to X-ray irradiation.

Caspase-3 is a critical effector caspase for apoptosis, which cleaves proteins, including cytoskeletal and associated proteins, kinases, and members of the Bcl-2 family of apoptosis-related proteins. This leads to changes in apoptotic morphology, such as membrane externalization and cytoplasm and nuclear condensation. It has been reported that pro-caspase-3 is activated in the cytosol. However, it remains obscure how caspase-3 activation correlates to serial changes in cell morphology during apoptosis. The current study was therefore undertaken to assess the relationship between caspase-3 activation and its subcellular localization and alterations in apoptotic morphology in MOLT-4 human leukemia cells exposed to X-ray irradiation. Fluorescence labeled inhibitor of caspases (FLICA) was used to detect caspase-3 activity in apoptotic cells in this project; cell morphology and caspase-3 sub-localization were determined by confocal microscopy. Our data showed that MOLT-4 cells presented typical morphological changes in apoptosis, such as membrane reversion, DNA fragmentation, and formation of apoptotic cell bodies following 10 Gray (Gy) of X-ray irradiation. Caspase-3 was activated 2 h after X-ray irradiation, and its activity increased markedly after 4-6-h exposure. Membrane reversion in MOLT-4 leukemia cells was detected by Annexin V assay at 4 h following X-ray irradiation, 2 h after the elevated caspase-3 activity was measured. Cytologically, activation of caspase-3 was first observed close to the inside surface of the cellular membrane, then transferred to the cytoplasm, and finally translocated to the nuclear region. We conclude that caspase-3 is activated in MOLT-4 cells following exposure to X-rays, and that the enhanced caspase-3 activity and its sub-localization shifting is correlated to changes in apoptotic morphology. The spatial shift of activated caspase-3 in X-ray-induced apoptotic MOLT-4 leukemia cells is a process of crucial importance for apoptosis.

Apoptosis↗

PubMed2004

[The analysis of various extent visual field defect in chronic glaucoma patients].

PURPOSE: To study the situation for the follow eye visual field defect of patients with severe visual field loss in 1 eye from chronic glaucoma,and to analyze the relative risk factors for visual field defect in such eyes. METHODS: The visual field defect scores of fellow eyes were calculated in 47 cases [primary chronic angle-closed glaucoma (PACG) 23 cases and primary open angle glaucoma (POAG) 24 cases] with severe visual field loss in 1 eye (visual field defect score > or = 12). The relations were analyzed between the visual field defect scores of fellow eyes and the visual acuity,the maximal and the mean intraocular pressure (IOP), ages, refraction, diagnosis, the last periods of glaucoma, gender and the anti-glaucoma surgery history. Spearman correlation analyse was used to estimated the correlation between the visual field defect scores of fellow eyes and the above factors. RESULTS: In the fellow eyes of the 23 cases PACG, 4 cases showed no visual field defect (score 0),5 cases showed the mild visual field defect (score 1-5), 7 cases showed the moderate visual field defect (score 6-11), 7 cases showed the severe or end-stage visual field defect (score 12-20). In the fellow eyes of the 24 cases POAG, 4 cases showed the mild visual field defect (score 1-5), 9 cases showed the moderate visual field defect (score 6-11), 11 cases showed the severe or end-stage visual field defect (score 12-20). The visual field defect score of fellow eyes in the last periods more than or equal to 10 years PACG group was significantly larger than that in the last periods less than 10 years PACG group (Z=2.8380, P=0.0224). The visual field defect score of fellow eyes in the mean IOP more than 18 mmHg PACG group was significantly larger than that in the mean IOP less than or equal to 18 mmHg PACG group (Z=1.9174, P=0.0276). The visual field defect score of fellow eyes in the anti-glaucoma surgery history POAG group was significantly larger than that in the non-anti-glaucoma surgery history POAG group (Z= 2.2377, P=0.0252). The significant positive correlation was found between the visual field defect scores and the mean IOP of the fellow eyes in the PACG group (r=0.4763, P= 0.0216),and the significant negative correlation was found between the visual field defect score and the visual acuity of the fellow eyes in the PACG group (r=-0.4416, P= 0.0349). CONCLUSION: Among the PACG with severe visual field loss in 1 eye, the visual field defect extent in the fellow eyes was related to the mean IOP, the last periods of PACG and the visual acuity of the fellow eyes. The visual field defect score was positively correlated with the mean IOP, and negatively correlated with the visual acuity of the fellow eyes.

Aged↗

PubMed2003

[Scoring method evaluation for threshold visual field defect in glaucoma].

PURPOSE: To evaluate the validity and reliability of visual field defect scoring method in glaucoma. METHODS: The visual field defects of 91 glaucoma cases (91 eyes) were scored with the Advanced Glaucoma Intervention Study (AGIS) modified scoring method, and analyzed the relation and correlation between the score and cup/disk ratio, mean defect (MD) and loss variance (LV). RESULTS: The larger the score was, the larger the cup/disk ratio, MD and LV were. The significant positive correlation was found between the score and the cup/disk ratio (r = 0.8712), and the correlation coefficient was larger than that of between the MD, LV and cup/disk ratio. CONCLUSION: The visual field defect score could more accurately reflect the situation of glaucomatous optic nerve damage than visual field indices, and could quantify the visual field damage extent in glaucoma.

Adolescent↗

PubMed2002

[Implication of non-perforating deep sclerectomy with amniotic membrane implantation for primary open-angle glaucoma].

PURPOSE: To evaluate the efficacy of non-perforating deep sclerectomy (NPDS) with amniotic membrane implantation for primary open-angle glaucoma (POAG). METHODS: Fourteen cases (23 eyes) of POAG underwent NPDS with amniotic membrane implantation. NPDS was performed with a fornix-based conjunctival flap using 0. 04% mitomycin C(MMC) under the scleral flap for 4 minutes. A 6 mm x 9 mm amniotic membrane was then placed under the scleral flap and sutured using 10-0 nylon. RESULTS: One month postoperatively, the intraocular pressure (IOP) was less or equal to 21 mmHg in 23 eyes, with a total success rate of 100%. After 3 months of follow-up for 20 eyes, the completely success rate was 90%, and the partly success rate was 100%. After 6 months of follow-up for 11 eyes, the completely success rate was 72.7%, the partly success rate was 100%, and the visual acuity had no significance between the pre-operation and post-operation. After 12 months of follow-up for 6 eyes, the success rate was 66. 7%. A good bleb formation was seen in the eyes and the IOP was controlled successfully. No serious complication was found in all eyes. CONCLUSION: Amniotic membrane is an effective and safe implantation material for NPDS.

Adolescent↗

PubMed2002

[Comparitive study of the threshold variability between blue-on-yellow perimetry and white-on-white perimetry].

PURPOSE: To compare the threshold variability of blue-on-yellow (B/Y) perimetry with white-white(W/W) perimetry, and evaluate the reproducibility of B/Y perimetry. METHODS: The B/Y perimetry and W/W perimetry in the Octopus 101 perimetry were used to examine the visual fields of 12 normal subjects (24 eyes), 16 cases (32 eyes) of primary open angle glaucoma (POAG), and 7 cases (14 eyes) of suspected POAG respectively. The B/Y perimetry and W/W perimetry were repeated to examine within 2 weeks. The point by point threshold variability of the two perimetries were compared and analysed. RESULTS: The total mean threshold variability for B/Y perimetry (2.61 +/- 0.94) dB was greater than that for W/W perimetry (2.11 +/- 0.90) dB in all subjects, but it had no significance (P = 0.6244). The total mean threshold variability for B/Y perimetry (2.07 +/- 0.54) dB was significantly greater than that for W/W perimetry (1.50 +/- 0.34) dB in normal subjects (P = 0.0006), while no significance was found in suspected POAG and POAG groups between the two perimetries (P = 0.0523 and 0.9371). The threshold variability in the areas of some eccentricities for B/Y perimetry were significantly greater than that for W/W perimetry in normal subjects and suspected POAG group, but no significance was found in POAG group for all eccentricities between the two perimetries. CONCLUSION: The threshold variability for B/Y perimetry was greater than that for W/W perimetry in normal subjects, but no significance was found in suspected POAG and POAG between the two perimetries.

Adult↗