Biomedical subjects

Junwen Zeng

Publications and source records attributed to Junwen Zeng.

9 recordsLinked to original sources

PubMed2025

Intraocular pressure is a promising target for myopia control.

BACKGROUND: Myopia presents a noteworthy global health concern, urging exploration of innovative treatments. The role of intraocular pressure (IOP) in regulating the progression of myopia has been controversial. METHODS: To investigate the impact of reducing IOP to varying extents on myopia progression, three groups receiving distinct IOP-lowering medications (Brinzolamide, Latanoprost, and a combination of Brinzolamide and Latanoprost) were designed in a form-deprived myopic guinea pig model. Additionally, proteomics analyses were conducted to identify differentially expressed proteins in the sclera. RESULTS: Based on 24-h and 4-week IOP monitoring, the group receiving both Brinzolamide and Latanoprost exhibited the greatest magnitude of IOP reduction and the most significant inhibition of axial length (AL) growth. Moreover, the administration of IOP-lowering medications increased choroidal thickness and induced alterations in the structure of scleral collagen fibrils. Notably, scleral proteomics revealed remodeling processes associated with key mechanisms, including proteolysis, fibrinolysis, and metal ion binding. CONCLUSIONS: Our findings highlight that pressure-dependent scleral remodeling contributes to the deceleration of AL elongation. These results underscore the efficacy of IOP reduction in mitigating the progression of myopia, providing a promising alternative strategy for myopia management.

Myopia↗

PubMed2005

Topographical evaluation of the decentration of orthokeratology lenses.

PURPOSE: To evaluate the amount of lens decentration and various factors affecting decentration after orthokeratology lens wear and to observe the effect of decentration on the visual functions. METHODS: Two kinds of orthokeratology lenses were fitted to 270 eyes of 135 patients [initial mean refractive error: (-3.98+/-1.51)D]. Humphery Instruments ATLAS 990 was used for the computer-assisted analysis of corneal topographical maps. The examination of corneal topography was performed on patients before and after 6 months of wearing orthokeratology lenses. The amount of decentration of orthokeratology lenses was measured by finding the distance between center of optic zone and the pupil center. The factors influencing the amount of decentration were analyzed, including the initial refraction error, astigmatism, keratometry values, corneal eccentricity, and the diameter of lens. Visual symptoms including monocular diplopia, glare around lights were recorded to evaluate the effects of decentration on visual functions. RESULTS: The mean amount of decentration was (0.49+/-0.34) mm after one night's wear. The mean amount of decentration after 1 month, 3 months and 6 months was (0.57+/-0.41) mm, (0.55+/-0.48) mm and (0.59+/-0.39) mm, respectively. After one month, the amount of decentration was less than 0.50 mm in 51.1% eyes, 0.50-1.0 mm in 35.6% eyes and more than 1.00 mm in 13.3% eyes. The direction of decentration of more than 0.50 mm was mainly in the temporal quadrant (48.5%). Patients with greater initial astigmatism and smaller lenses showed greater decentration (P<0.05). There was no statistically significant difference in decentration between the two groups with different corneal eccentricities and keratometry values (P>0.05). The amount of decentration was greater in patients who complained of monocular diplopia and glare. CONCLUSIONS: The amount of decentration of orthokeratology depends on the initial refractive error, astigmatism and the design of orthokeratology lenses. Improvement in fitting technology and lens design can lead to reduced incidence of decentration and visual symptoms.

Adolescent↗

PubMed2005

Multi-dimension aspiration control mode in phacoemulsification.

PURPOSE: Multi-dimension aspiration control mode was put forward in this study. Accuracy of multi-dimension aspiration control model was compared to simple traditional pedal control model. METHODS: Induced by high aspiration pressure (200-250 mmHg), hard nucleus (> OR = Grade III ) of senile cataract was chopped before phacoemulsification in 170 patients (174 eyes). Ninety-one patients (94 eyes) accepted multi-dimension aspiration control model in which aspiration direction, distance and targets prevention were adjusted by phaco-tip besides traditional pedal control. Another 79 patients (80 eyes) were compared as reviewed group, aspiration of which was controlled simply by traditional pedal control. Postcapsular rupture rates (PCRR) were compared between two groups. RESULTS: Multi-dimension control model could make the terminal effects cooperate with phacoemulsification more precisely and protect post capsular from damage (chi(2) =5.41, P < 0.02). CONCLUSION: Multi-dimension control model could improve the accuracy of aspiration effects and protect postcapsular from damage.

Humans↗

PubMed2005

Detection of molecular weight of PMCA isoform with 20 cm SDS PAGE electrophoresis: compared with 8 cm SDS PAGE.

PURPOSE: To compare the effect of 20 cm SDS-PAGE electrophoresis, which is most widely used in proteomic research, in identifying human lens epithelium B3 (HLE B3) cells plasma membrane calcium ATPase (PMCA) isoform's apparent molecular weight (MW), with that of 8 cm SDS-PAGE electrophoresis. METHOD: HLE B-3 cells were cultured and membrane protein sample was collected. Part of the sample is electrophoresised with 20 cm gel, 16 mA/gel for 1.5 hrs and then 24 mA/gel for 4-5 hrs. The same sample is electrophoresised with 8cm mini gel, 200V for 2 hrs. Protein marker of known MW was run with the sample in the same gel. The resulting separated proteins were transferred to polyvinylidene difluoride (PVDF) membrane and Western blot were used to identify the PMCA isoform with specific antibody against PMCA 1, 2, 4. The apparent MW was calculated in reference to the known protein marker that was electrophoresised in the same gel. RESULT: In 8 cm gel the distance between 208 kDa and 126 kDa band was about 6.1 mm, while that of 20 cm gel was 32.8 mm. The distance between 126 kDa and 97 kDa was about 5.2 mm, while that of 20 cm gel was 20.2 mm. The migration distance differences of protein bands were significantly much longer in 20 cm gel than in 8 cm gel (P < 0.005). But the bands were generally more condensed in 8 cm gel. The apparent MW of PMCA1, 2, 4 were 153.8, 153.5 and 152.9 kDa respectively. In the 20 cm gel, the apparent MW for PMCA1, 2, 4 was 153.1, 125.5 and 147.4 kDa respectively. CONCLUSION: Both the 20 cm gel and 8 cm gel successful identified PMCA 1, 2, 4 in HLE B-3 cells. The apparent MW for PMCA1, 2, 4 was 153.8, 153.5 and 152.9 kDa respectively in 8 cm gel, and 153.1,125.5 and 147.4 kDa respectively in 20 cm gel. PMCA2 probably had some kinds of degradation during the long electrophoresis time in 20 cm gel.

Blotting, Western↗

PubMed2004

Refractive error and visual impairment in urban children in southern china.

PURPOSE: To assess the prevalence of refractive error and visual impairment in school-age children in a metropolitan area of southern China. METHODS: Random selection of geographically defined clusters was used to identify children 5 to 15 years of age in Guangzhou. Children in 22 clusters were enumerated through a door-to-door survey and examined in 71 schools and 19 community facilities from October 2002 to January 2003. The examination included visual acuity measurements, ocular motility evaluation, retinoscopy, and autorefraction under cycloplegia and examination of the external eye, anterior segment, media, and fundus. RESULTS: A total of 5053 children living in 4814 households were enumerated, and 4364 (86.4%) were examined. The prevalence of uncorrected, presenting, and best-corrected visual acuity 20/40 or worse in the better eye was 22.3%, 10.3%, and 0.62%, respectively. Refractive error was the cause in 94.9% of the 2335 eyes with reduced vision, amblyopia in 1.9%, other causes in 0.4%, and unexplained causes in the remaining 2.8%. External and anterior segment abnormalities were seen in 1496 (34.3%) children, mainly minor conjunctival abnormalities. Media and fundus abnormalities were observed in 32 (0.73%) children. Myopia (spherical equivalent of at least -0.50 D in either eye) measured with retinoscopy affected 73.1% of children 15 years of age, 78.4% with autorefraction. The prevalence of myopia was 3.3% in 5-year-olds with retinoscopy and 5.7% with autorefraction. Females had a significantly higher risk of myopia. Hyperopia (+2.00 D or more) measured with retinoscopy was present in 16.7% of 5-year-olds, 17.0% with autorefraction. The prevalence of hyperopia was below 1% in 15-year-olds, with both methods. Astigmatism (cylinder of > or = 0.75 D) was present in 33.6% of children with retinoscopy and in 42.7% with autorefraction. CONCLUSIONS: The prevalence of reduced vision because of myopia is high in school-age children living in metropolitan Guangzhou, representing an important public health problem. One third of these children do not have the necessary corrective spectacles. Effective strategies are needed to eliminate this easily treated cause of significant visual impairment.

Adolescent↗

PubMed2004

[Efficacy of rigid gas permeable contact lens for the correction of mixed astigmatism].

PURPOSE: To evaluate the efficacy of rigid gas permeable contact lens (RGPCL) for the correction of mixed astigmatism. METHODS: Patients with mixed astigmatism by mydriasis refraction were selected as subjects. Routine eye check was performed to exclude contraindication of contact lens. Investigation included visual acuity, keratometry and corneal topography. Average keratometry value was chose as base curve of the first trial lens. Final base curve, diameter, material and edge of lens were prescribed according to the centralized position, movement and fluorescence pattern of trial lens. After over refraction, final refractive power of lens was prescribed. Corrective visual acuity with spectacle and rigid gas permeable contact lens were compared in 24 patients (31 eyes). RESULTS: Corrective visual acuity of patients with RGPCL was much better than those with spectacle. CONCLUSIONS: RGPCL is safe and effective to correct mixed astigmatism.

Adolescent↗

PubMed2003

[Role of p38MAPKs pathway in the growth inhibition of rabbit lens epithelial cells induced by EGCG].

PURPOSE: Study the role of p38MAPKs pathway in the growth inhibition of rabbit lens epithelial cells(LECs) induced by green tea extract (-)-Epigallocatechin-3-gallate (EGCG). METHODS: (1) MTT colormetric assay was used to study the effect of p38 specific inhibitors SB203580 on LECs growth. (2) MTT colormetric was used to study the effect of SB203580 on LECs growth inhibition induced by EGCG. (3) Western blotting methods was used to study the effect of EGCG on the kinase phosphorylation- and nonphosphorylation-level of p38. RESULTS: (1) When LECs were preincubated with 25 mumol/L, 50 mumol/L SB203580 for 1 h, 100 mumol/L EGCG had little influence on LECs proliferation. It showed great protects effect significantly when increased to 200 mumol/L. (2) Basic phosphorylation-level of p38 were very weak in LECs, but it increased with EGCG concentration increased and reached maximum at 200 mumol/L. 15 min after 200 mumol/L was added, the phosphorylation-level was the highest and began to fall, but even at the end of our test, it still stayed higher than that of basic level. The nonphosphorylation-level of p38 remained stable in all test. CONCLUSIONS: The LECs proliferation inhibition induced by EGCG is through p38 pathway at lease partially.

Animals↗

PubMed2002

[Detection of cell cycle related gene expression in cultured immortalized human lens epithelial cell].

OBJECTIVE: To investigate the gene expression of cyclin E, cyclin-dependent-kinase 2 (CDK(2)) and CDK inhibitor (CKI) p21 during cell cycle of the human lens epithelial cell (HLEC) for elucidating the molecular mechanism of proliferation of HLEC and the formation of posterior capsular opacification (PCO). METHODS: HLE-B3 cell line was cultured in vitro under MEM medium with 15% fetal bovine serum. The cell cycle was analyzed by flow cytometry (FCM) system. The cell cycle was synchronized by double thymidine block method. The mRNA was detected by reverse transcription polymerase chain reaction (RT-PCR). The total RNA was separated from cells at different phases. Protein expression was detected with immunohistochemistry or western blotting method. The primary antibodies were rabbit anti-human cyclin E polyclonal antibody, mouse anti-human p21 and CDK(2) monoclonal antibody, respectively. RESULTS: FCM showed that G(1) phase was about 33.5%, S phase cells about 46.1%, and the G(2) phase about 20.4%, total cells in G(2) and S phase were over 60%. It was suggested that HLE- B3 cells have relatively more capacity of mitosis than normal LEC. The mRNA expression of CDK(2) was found at all phases of cell cycle during synchronization, but cyclin E mRNA only expressed during synchronized cells, and not expressed in non-synchronized cells. Only Sphase cells could express very low p21 mRNA. There was no any positive signal of cyclin E by immunohistochemistry or western blot. CDK(2) protein detected by Western blot expressed at all phases. The p21 protein was expressed in a few cells by immunohistochemistry, but p21 could not detected by western blotting. These results showed cyclin E and CDK(2) were higher expressed than p21 in transcriptional level and translational level. CONCLUSIONS: There is mRNA expression of cyclin E, CDK(2) and p21 during the cell cycle in HLE-B3 cell line, but it means the imbalance of the association of CDK and CKI. These results suggest that the imbalance expression of cyclin, CDK and p21 be the molecular mechanism of PCO.

Blotting, Western↗

PubMed2002

A preliminary report of 40 cases of strabismus microsurgery.

OBJECTIVE: To improve the quality of strabismus surgery and to find out the role of microsurgery in the field of strabismus. METHODS: We performed separation and preservation of anterior ciliary vessels (ACV), adjustable sutures, routine rectus recession, and oblique muscle surgeries under microscope in 13 cases of comitant strabismus, 19 cases of A-V syndrome and 8 cases of paralytic strabismus. RESULTS: Surgeries were performed in a very clear field under microscope. We successfully did vascular microdissection and ACV preservation. Also with the use of microscope, various kinds of strabismus microsurgery videos were recorded. CONCLUSIONS: Microscopic technique can be used to enhance the quality and accuracy of strabismus surgery and to reduce surgical damage, postoperative inflammatory reaction and scar formation. All kinds of strabismus surgery , especially, oblique muscles and complex paralytic operations can be performed under microscope.

Adolescent↗