ABSTRACT
Background Oxidative damage plays an important role in pathogenesis of age-related macular degeneration( AMD ),and its mechanism is the destroy of blood-retinal barrier.Müller cells is a primary component to stabilize the inner barrier of the blood-retina.Researches showed that epidermal growth factor(EGF) can promote the proliferation and migration of animal Müller cells,but less study was found in the effect of EGF on human Müller cells. Objective The present study was to investigate the effects of EGF on the proliferation and migration of human Müller cells and its molecular mechanism. Methods Human Müller cell line MIO-M1 cells were cultured and incubated,and cultured cells were identified using glial fibrillory acidic protein (GFAP),factor Ⅷ,α-smooth muscle actin( α-SMA ),keratin and S-100.Different concentrations of EGF( 0,1,10,30,100 mg/L)was added in freeserum DMEM,and the positive rate of the cells was calculated using 5-bromo-2-deoxyuridine(BrdU) method.The cells were divided into EGF group,H2 O2 group,EGF + H2 O2 group,glucose oxidase ( GO ) group,GO + EGF group,EGF + LY294002+H2O2 group according to the different intervention,and the effects of LY294002 on the proliferation of Müller cells (A590 )were detected by colorimetric assay for cellular growth and survival( MTT assay).The scratch test of Müller cells was used to assess the influence of EGF(0,1,10,30,100 mg/L)on H2 O2-induced damage of human Müller cell.Western blot was used to detect the cell proliferation under the protection of EGF on co-cultured cells using LY294002 and H2O2 and the activation of Akt signal pathways. Results The proliferative rates of the cells were 28.0％,32.9％,39.0％ in 10,30,100 mg/L EGF groups respectively and obviously higher than those in 0,1 mg/L EGF groups (24.5 ％,26.2 ％ ).Under the H2O2 culture,GO culture,respectively,the A570 value of the Müller cell in high concentrations of EGF groups was significantly increased in comparison with lower concentrations EGF groups with the statistical significance among the groups( F=23.582,P=0.000).Compared with EGF+H2O2 group,the A570value of the Müller cells was lowed in EGF+LY294002+H2O2 group.The maximum migration rate of Müller cells was found in 10 mg/L EGF group.Western blot revealed that the presence of H2O2 reinforced the expression of Akt in Müller cells,however,pretreatment with 100 mg/L EGF antagonized the harmful effect of H2O2 on Müller cells.Meanwhile,pretreatment with EGF and LY294002 reduced the expression of Akt in Müller cells. Conclusions EGF can induce the proliferation and migration of human Müller cells with the strongest effect in 10 mg/L.100 mg/L exogenous EGF has a stronger protection to the Müiller cells against H2O2-induced cell damage by activating the PI3KAkt cell survival pathway.
ABSTRACT
Background The evaluation of visual function after laser in situ keratomileusis(LASIK) mainly focuses on the study of contrast sensitivity funetion (CSF).However,CSF measurement is a subjective method and therefore has a limiting in application.A point spread function (PSF) is becoming a study topic because of its objectivity in assessing visual quality.Objective Present study was to evaluate the change of the modulation transfer function (MTF) of eyes and compare the optical and visual quality of human eyes after LASIK.Methods Thirty-six patients(72 eyes) were included in this study.The patients were divided into low myopia(-2.72±0.52 D),moderate myopia (-4.89+0.80 D) and high myopia (-8.00+0.98 D) groups according to the spherical equivalent (SE)diopter before the sugery.The uncorrected visual acuity (UCVA),best corrected visual acuity (BCVA) were examined before and after operation,and PSF data was obtained with Topoeon PSF-1000 analyzer under the 3.0 mm and 6.0 mm pupil size conditions.The follow-up visits of the patients were scheduled at the 7th days,1 st and 3rd months.Written informed consent was obtained from each patient before this study. ResuIts The MTF values among the three refractive groups were significantly different between 3 mm and 6 mm pupil preoperatively (P＜0.05).Under the condition of 3 mm pupil size,the MTF values in the spatial frequencies of 2.98 cpd and 14.88 cpd were significantly declined in different time points after operation in comparison with preoperative ones (P＜0.05).However,the MTF changes had no statistical significance in the spatial frequencies from 18.85-37.70 cpd among various time points(P＞0.05).Under the condition of the 6 mm pupil size,MTF values in low and moderate myopia groups were reduced after operation in comparison with before operation at the spatial frequencies from 2.98-7.44 cpd(P＜0.05),however,there were no obvious difference was found in the spatial frequencies of 9.42-37.70 cpd(P＞0.05).The MTF values of high myopia group was decreased significantly at all spatial frequencies(P＜0.05).The MTF values improved gradually as the prolong of time after operation but was still lower at the 3rd postoperative month than that of preoperation. Conclusion The postoperative visual quality is associated with refractive power and pupil diameter.PSF is a feasible method in assessing the early visual quality after LASIK.
ABSTRACT
<p><b>OBJECTIVE</b>To study the feasibility of applying expanded forehead axial flaps with fascia pedicles carrying bilateral frontal branches of superficial temporal artery and vein (expanded forehead axial flap with double pedicles in brief, EFAF-DP) in repairing scars in submaxillary region.</p><p><b>METHODS</b>Sixteen patients with mandibular scars hospitalized in Department of Burns and Plastic Surgery of the First Hospital Affiliated to Fuzhou General Hospital in Nanjing Military Area Command from July 2005 to December 2009 were repaired with EFAF-DP. The operation consisted of 3 stages. Before operation, the location and course of superficial temporal arteries and veins (STAV) and their frontal and parietal branches were identified with Ultrasonic Doppler blood flow detector. In stage I, STAV were dissected from the frontalis muscle as a pedicle to form a skin soft tissue space to hold the dilator of a proper size. In stage II, after gradual dilation by repeated filling with saline, the dilator was removed. EFAF-DP was dissected to repair mandibular scar. Donor site was closed with sutures. In stage III, flap pedicles were divided and pruned.</p><p><b>RESULTS</b>Flap sizes ranged from 25 cm × 6 cm to 33 cm × 16 cm. The duration of dilation was 3-5 months, with 3.6 months in average. Ten patients underwent the operation of EFAF-DP transplantation and cervical skin dilatation. All flaps survived with healing of wounds. Disorder of venous return at the distal end of one flap was seen after second stage surgery, and it was corrected after comprehensive treatment including relieving spasm and improving venous return. Donor site wounds healed with normally grown hair without cicatricial alopecia along the hairline. Few hairs grew around mandible in one female patient out of the three (no hair grew on flaps of other two patients). This female patient and two male patients requesting for beard plasty received laser depilation treatment 1 to 3 months after discharge, with good result. Other male patients received no special treatment for their beard, and they shaped their beard with shaver. Sixteen patients were followed up for 6 to 24 months, and the shape of the flaps and beard (excluding female patients) were satisfactory with good appearance, satisfactory skin color and texture. The mobility of neck was obviously improved.</p><p><b>CONCLUSIONS</b>EFAF-DP provides bigger areas of a thin flap besides promoting vascularization of new vessels of flap. Extra expanded skin can be directly sutured at the fringe of hairline, which makes skin grafting unnecessary, and decreases the incidence of secondary deformity in donor sites. Some hair carried by the flaps can be directly used for beard reconstruction after rotation to help the male patients have a better appearance.</p>