Biomedical subjects

Yi-zhi Liu

Publications and source records attributed to Yi-zhi Liu.

11 recordsLinked to original sources

PubMed2005

[Changes of blood-aqueous barrier after phacoemulsification in patients with previous glaucoma filtering surgery].

OBJECTIVE: To evaluate the effect of trabeculectomy and/or phacoemulsification surgery on blood-aqueous barrier function. METHODS: Phacoemulsification with implantation of intraocular lens was performed on 46 cataract eyes of 40 glaucoma patients following previous trabeculectomy (group 1), and 64 cataract eyes of 60 patients (group 2). The aqueous flare and cells were examined preoperatively and on days 1, 7, 30, 90 postoperatively using a laser flare-cell meter (LFCM). RESULTS: The mean aqueous flare values were (15.12 +/- 2.87), (40.24 +/- 3.75), (24.33 +/- 3.38), (21.18 +/- 1.77), (16.51 +/- 1.70) photon counts/ms in group 1 preoperatively and on days 1, 7, 30, 90 after surgery (P < 0.05) respectively; and were (6.94 +/- 2.34), (26.27 +/- 10.21), (13.96 +/- 6.44), (9.07 +/- 2.67), (7.16 +/- 1.89) photon counts/ms in group 2 (P < 0.05) respectively. CONCLUSIONS: Trabeculectomy can breakdown blood-aqueous barrier permanently while phacoemulsification damage the blood-aqueous barrier transiently. Phacoemulsification combined with a previous trabeculectomy can enhance this damage.

Aged↗

PubMed2005

[Quantities of human papillomavirus 16 E6 mRNA and its relationship with expression of survivin in cervical cancer].

OBJECTIVE: To investigate the quantities of human papillomavirus (HPV) 16 E6 gene and to study its relationship with the expression of survivin in cervical carcinoma. METHODS: In 148 patients including cervical intraepithelial neoplasia (CIN), cervical carcinoma and chronic cervicitis, the quantities of HPV 16 E6 gene were detected by semiquantitative polymerase chain reaction (PCR); and the expressions of survivin were measured by immunohistochemical streptavidin-biotin peroxidase (SP) assay. RESULTS: The quantities of HPV 16 E6 gene were 0.3 +/- 0.4, 0.6 +/- 0.4, 1.8 +/- 0.6 and 2.4 +/- 0.6, and expression rates of survivin were 7%, 31%, 63% and 84% respectively in chronic cervicitis, CIN I, CIN II-III and cervical cancer tissues. The quantities of HPV 16 E6 gene and the expressions of survivin tended to increase along with the tumor progression (P < 0.05). The quantities of HPV16 E6 gene and the expressions of survivin of CIN I, II-III or cervical cancer were significantly higher than that of chronic cervicitis or CIN I (P < 0.01). Positive rank correlation between the quantities of HPV16 E6 gene and the expression of survivin was observed in cervical carcinoma (gamma(s) = 0.62, P < 0.05). CONCLUSIONS: The quantities of HPV16 E6 gene appear to be associated with an increased risk of developing cervical cancer. Survivin overexpression might play an important role in the process of cervical carcinoma.

Adult↗

PubMed2005

[Inhibitory effects of human papilloma virus 18 E6 gene in HeLa cell transfected with shRNA].

OBJECTIVE: To investigate the inhibition of HPV18E6 gene in HeLa cell transfected with plasmid expressing human papilloma virus 18 E6 (HPV18E6) short hairpin RNA (shRNA). METHODS: We synthesized two HPV18E6 shRNA frames and sub-cloned them into pSUPER which can express shRNA in mammalian cells to construct pE6-1shRNA and pE6-2shRNA which were mutant in E6 shRNA frame. The pE6-1shRNA, pE6-2shRNA and pcDNA3.1 were co-transfected into HeLa cells by cationic liposome respectively and the positive transfectants were selected by G418. The HPV18E6 mRNA and protein expression level was detected by semi-quantitative RT-PCR and streptavidin-peroxidase conjugated method (SP) to assay the inhibitory effects of pE6shRNA. RESULTS: We successfully constructed several new HeLa cell lines transfected with pE6-1shRNA and pE6-2shRNA. In the HeLa cells without transfection and the HeLa cells transfected with pE6-1shRNA plasmid, the HPV18E6 mRNA levels were 1.14 +/- 0.45, 0.76 +/- 0.28 respectively, and the difference of HPV18E6 mRNA levels was significant (P < 0.05). The inhibition efficiency of HPV18E6 gene mRNA was 33.3% and the HPV18E6 protein levels were declined after transfection with pE6-1shRNA. In the HeLa cells transfected with pE6-2shRNA and pSUPER plasmids, HPV18E6 mRNA and protein expression levels were not different from those in wild HeLa cells. CONCLUSIONS: The pE6-1shRNA plasmid can inhibit HPV18E6 expression in HeLa cells, which is persistent, specific and heritable.

DNA-Binding Proteins↗

PubMed2004

[Disorders of the blood-aqueous barrier after phacoemulsification].

OBJECTIVE: To determine the status of blood-aqueous barrier after small incision phacoemulsification with implantation of foldable intraocular lens. METHODS: The blood-aqueous barrier status in 64 eyes of 60 patients who underwent cataract surgery was examined using a laser flare cell meter. The protein level of anterior chamber aqueous humor was evaluated by measurement of the flare value preoperatively and postoperatively. RESULTS: The mean preoperative flare intensity was (6.94 +/- 0.34) photon counts/ms, which increased to (26.27 +/- 1.37), (13.96 +/- 1.05), (9.07 +/- 0.43) and (7.16 +/- 0.27) photon counts/ms on days 1, 7, 30 and 90 after the surgery, respectively. Significantly statistical differences on flare values were found between preoperative data and those on days 1, 7 and 30 after surgery. The blood-aqueous barrier was recovered on day 90 postoperatively. The variables such as age, gender, eye (left/right) had no influence on the flare value. Patients with iris prolapse had a higher flare value at day 1 and day 7 after the surgery. CONCLUSIONS: Blood-aqueous barrier after phacoemulsification with implantation of intraocular lens can be measured quantitatively by the laser flare cell meter. The blood-aqueous barrier disorders can be recovered shortly after phacoemulsification.

Aged↗

PubMed2004

[Identification of rabbit lens proteins by two-dimensional gel electrophoreses and mass spectrometry].

OBJECTIVE: To study the role of lens proteomics using two-dimensional electrophoresis (2-DE) and mass spectrometry in order to exploring novel effective ways for cataract prevention and therapy. METHODS: The proteins of the three-month-year old rabbit lens were separated using immobilized pH gradients 2-DE. Image analysis was carried out using Image Master 2D Elite 3.01 software package. Most of the crystallines was identified by matrix assisted laser adsorption/ionization-time of-flight-mass spectrometry (MALDI-TOF-MS). RESULTS: The maps of 2-DE showed that lens proteins were in the section of pH 5 - 9 and the relative molecular weight was 14,000 - 94,000, while relative molecular weight of more abundant crystalline was localized at 14,000 - 40,000. About 180 protein spots were detected with the similar PI, molecular weight and quantity of each spot could be acquired by image analysis software. Sixteen crystallines were identified using MALDI-TOF-MS. CONCLUSION: Proteomic analysis of lens can be accomplished and the proteins can be well separated and analyzed using 2-DE and mass spectrometry. This technique offers a new avenue for analyses of lens proteins and to assess their differential expression in cataract, and may thus provide a novel approach to cataract prevention and therapy.

Animals↗

PubMed2004

[A preliminary report on bimanual microphacoemulsification].

OBJECTIVE: To evaluate the surgical technique, feasibility, and outcome of bimanual microphacoemulsification. METHODS: The preliminary clinical study included 132 senile cataract eyes. A temporal clear cornea incision was made using 19G microvitreoretinal blade with the exterior incision length of 1.4 mm, the interior incision length of 1.2 mm, and the tunnel length of 1.0 mm. A 1.2 mm x 1.0 mm clear cornea side port was created with 19G microvitreoretinal blade at 12 o'clock in the right eye or 6 o'clock in the left eye. A sleeveless titanium phaco needle with an outer diameter of 0.9 mm was inserted through the temporal clear cornea incision. An irrigating chopper was inserted through the side port as the left-hand instrument, bimanual nucleofractis and nuclear emulsification were performed using quick chop technique. The lens cortical removal was performed bimanually with the Duet Bimanual I/A System. The study parameters included phacoemulsification time, intraoperative complications and early postoperative outcome. RESULTS: The mean Phacoemulsification time was 0.75 +/- 0.64 min. vision acuity equal or better than 0.5 were 55.30%, 87.12% and 90.15% after surgery one day, one week and one mother respectively. Eyes with 0.5 best corrected visual acuity amounted to 90.91%, while with 0.8, amounted to 77.27% all the treated eyes 1 month postoperation. The formation of anterior chamber was successfully maintained in every case. There was various degree of nuclear hardness in all of case studied. CONCLUSION: Bimanual microphacoemulsification is a feasible, secure, and effective surgery for cataract extraction through a sub-1.5 mm clear cornea incision.

Adult↗

PubMed2003

[Relationship between macrophages and apoptosis in patients with myelodysplastic syndromes].

OBJECTIVE: To observe the relationship between macrophage proliferation and cell apoptosis in patients with myelodysplastic syndromes (MDS). METHODS: A double labelling method of immunohistochemistry (alkaline phosphatase anti-alkaline phosphatase, APAAP) and ISEL (DNA in situ end labelling) was used to detect the positive CD68 expression (macrophages) and apoptosis on cold plastic embedded bone marrow biopsy sections in 30 MDS cases. 12 cases of iron deficient diseases (IDA) were used as the control. RESULTS: (1) The number of CD68 positive cells in MDS were higher than that in controls (29.2 +/- 33.0/mm(2) bone marrow tissue vs 21.2 +/- 16.7/mm(2)) (P > 0.05); (2) The number of apoptotic cells in MDS group was much higher than that in the controls (71.5 +/- 70.9/mm(2) vs 37.3 +/- 23.0/mm(2), P < 0.05); (3) The number of CD68 expression (35.5 +/- 37.0/mm(2)) and apoptosis (90.7 +/- 74.6/mm(2)) in less advanced MDS were much higher than that in advanced MDS group (14.6 +/- 11.7/mm(2) and 26.8 +/- 33.1/mm(2), P < 0.05 and < 0.01 respectively); (4) CD68 expression showed an obvious positive correlation to apoptosis in MDS cases (r = 0.83, P < 0.001); (5) CD68 positive cells did not show location correlation to apoptotic cells; (6) CD 68 positive cells in MDS showed simultaneous apoptosis. CONCLUSIONS: Over-apoptosis existed in MDS. Less advanced group has a higher ratio of apoptosis than in advanced group. The correlation between macrophages and apoptosis indicates the participation of TNFalpha in apoptosis-induction during MDS development.

Adolescent↗

PubMed2003

[Effects of exogenous p21 gene on cells cycle of human lens epithelial cells].

OBJECTIVE: To investigate the effects of transfected exogenous p21 gene on the cells cycle of HLE-B3 cells line. The feasibility of prevention of secondary cataract by gene therapy was evaluated. METHODS: Total length of human p21 gene cDNA was cloned on the parent's plasmid pcDNA3 to construct the recombinant plasmids of pcDNA3/p21, a large amount of pcDNA3/p21 plasmid DNA was prepared by QIAGEN endofree maxi kit. After harvest of the plasmid DNA, the HLE-B3 cells line was transfected. The cell growth was observed and the cells cycle was analyzed by flow cytometry. The expression of p21 mRNA was detected by RT-PCR and the expression of p21 protein was detected by immunohistochemistry and western blot analysis. RESULTS: Forty eight hours after transfection, the growth of transfected cells became slower, some cells floated and died; the control cells and blank plasmid (blank pcDNA3) transfected cells grew normally. Flow cytometry analysis revealed that the number of cells in G(1) phase increased markedly in transfected cells. The RT-PCR showed that the product of p21 in the transfected cells (dead or alive cells) was obviously higher than that of the controls. Immunohistochemical studies showed few positive cells in the controls, and very high positive signal was detected after transfection. Western blot showed a positive band at the level of 21 000 in transfected cells, no positive band could be found in the controls. CONCLUSION: Exogenous p21 gene can transfect the HLE-B3 cells and can be expressed. The transfection can affect the cells cycle by G(1) arrest and induces cells death through the apoptosis process. This result suggests that it is possible to prevent the occurrence of secondary cataract by gene therapy.

Cell Cycle↗

PubMed2003

[Changes of lens capsule after phacoemulsification].

OBJECTIVE: To observe the changes in the lens capsule after phacoemulsification and its effects on the position of intraocular lens (IOL) and to demonstrate the best position of IOL in relation to the anterior capsule. METHODS: The present series comprised 141 eyes in 127 patients underwent phacoemulsification and foldable lens implantation with 5 mm continuous curvilinear capsulorhexis. The changes in the lens capsule and the position of IOL with dilated pupil were observed using slit lamp microscope 3 months after the operation. RESULTS: Capsular bag shrinkage and white Soemmering ring along the margin of capsulorhexis were observed in all cases. Three different kinds of relationship between anterior capsule opening and the IOL optic surface were found, including the non-capture (68 eyes), partial-capture (52 eyes) and total-capture (21 eyes) relationships. The incidence of central posterior capsule opacification (PCO) was significantly higher in the total-capture group (47.6%) than that in the non-capture (11.7%) and partial-capture (21.2%) groups (P < 0.01). IOL in well centered position was significantly higher in the non-capture (91.2%) and total-capture (81.0%) groups than that in the partial-capture group (42.3%) (P < 0.01). CONCLUSION: In the present study, various changes in the lens capsule were observed after phacoemulsification and foldable lens implantation. It is suggested that keeping the IOL in a non-capture position is a key point to avoid the occurrence of PCO and IOL decentration.

Aged↗

PubMed2003

[Expression of Pax-6 homeobox gene in lens epithelial cells in vitro].

OBJECTIVE: To detect the gene expression of Pax-6 in cultured lens epithelial cells (LECs) of mouse in vitro in order to study the gene factor that maintains the LECs characteristics. METHODS: Cultured the LECs (passage 1 to 3) were used in the study, the expression of Pax-6 gene in LECs was demonstrated by reverse transcriptase polymerase chain reaction (RT-PCR), immunohistochemical staining and Western blot. RESULTS: The mRNA of Pax-6 gene was positive in primary culture, the first and second passage of LECs using RT-PCR. The protein of Pax-6 gene was also positive in Western blot and immunohistochemical staining, but it was weak positive in the third passage of LECs and none in all passages of negative control groups. CONCLUSION: The LECs are positive for the gene of Pax-6. The normal expression of Pax-6 gene is vital for maintaining the LECs characteristics.

Animals↗

PubMed2003

[Apoptotic characteristics of CD34 positive cells in myelodysplastic syndromes].

OBJECTIVE: To investigate the apoptotic situation of CD(34) positive cells in myelodysplastic syndromes (MDS). METHOD: In 36 MDS patients, immunocytochemical technique was used for the detection of the expression of CD(34) antigen and DNA in situ end labelling (ISEL) (fluorescein) for the apoptotic signals. Fourteen cases of iron deficiency anemias (IDA) were used as controls. RESULTS: (1) CD(34) expression in MDS group was much higher than that in controls (49.2 +/- 38.5 vs 10.2 +/- 9.7, P < 0.01), and MDS cases had an obviously higher apoptotic rate than control did (69.1 +/- 28.2 vs 17.8 +/- 11.2, P < 0.01). (2) Expression of CD(34) was higher in transforming group (P < 0.05) than in non-transforming and post-transforming groups. Apoptotic rates in both non-transforming/transforming group were higher than in post-transforming group (P < 0.02 and < 0.05 respectively). (3) No apoptosis was found in CD(34) positive cells in MDS; (4) Both CD(34) positive cells and apoptotic cells formed into small or large clusters but did not co-distributed in a given area. CONCLUSION: There is overexpression of CD(34) antigen on hematopoietic cells in MDS. High CD(34) expression accompanied high apoptosis coexisted in the process of transformation from MDS to AML. Apoptosis-resistance of these CD(34) positive cells suggested that they came from malignant hematopoietic cell clones.

Adolescent↗