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With the increasing prevalence of myopia among adolescents, the pathogenesis of this condition has garnered significant attention. Studies have discovered the expression of various hormone receptors in ocular tissues of both animals and humans. Additionally, changes in hormone levels accompany the development of myopia, although the exact relationships remain inconclusive. This article reviews the potential influences and mechanisms of action of endogenous hormones such as melatonin, serotonin, insulin, glucagon, sex hormones, vitamin D, and prostaglandins in ocular tissues including the retina, choroid, and sclera. It elaborates on the relationship between fluctuations in these hormone levels and the progression of myopia, aiming to provide guidance for exploring targets for myopia prevention and control.

Objective: To investigate ocular changes in the monocularly deprivation myopic model of mutant Lumican transgenic mice. Comparing influences on biological parameters and sclera development between Lumican transgenic and form deprivation mice, and to prepare for further study of pathogenesis of pathological myopia (PM). Methods: Experimental research. Lumican transgenic mice and wild mice were monocularly lid-sutured at ten days after birth. All eyes were divided into 6 groups, group A(32 eyes): control eyes in transgenic mice; group B(34 eyes): sutured eyes in transgenic mice; group C(34 eyes): fellow eyes in transgenic mice; group D(28 eyes): control eyes in wild mice; group E(32 eyes): sutured eyes in wild mice; group F(32 eyes): fellow eyes in wild mice. Refraction was measured by streak retinoscopye and axial length was measured by vernier caliper at 8 weeks (56 days) after birth. Lumican expression was detected by quantitative real-time PCR in all groups. Results: The refraction in group B and group E were (-0.38±1.10) D and (0.14±1.26)D respectively, which were significantly different compared with contralateral groups and normal control groups ( F= 9.525, 10.067; P< 0.01). The mean axial length were also increased in group B ((3.28 ± 0.07)mm and group E (3.24 ± 0.09)mm, ( F= 7.183, 6.671; P< 0.05). Expression level of Lumican mRNA in sclera was increased in group B, which was significantly different from group A and group C ( F= 6.262; P< 0.05). The expression of Lumican mRNA was increased in group B and C when compared with group E and F ( t= 4.772, 2.218, P< 0.05). Conclusions: Form-deprivation in mutant Lumican transgenic mice causes myopic changes in deprived eyes. The gene expression level of Lumican in sclera of transgenic mice is significantly increased compared with contralateral eyes or that of wild group. Lumican mutation may effect the development of PM, and the interaction of genetic and environmental factors may lead to development of PM. (Chin J Ophthalmol, 2016, 52: 850-855) .

Objective: To identify differentially expressed lumican in scleral tissue of eyes with primary open-angle glaucoma (POAG) and high myopia (HM)., Methods: Total RNA was isolated from scleral tissue of cadaveric eyes derived from normal donors, patient's eyes with diagnosed glaucoma and high myopia who accepted trabeculectomy. RNA was amplified, RT-PCR was used to measure the levels of mRNA. The ratio of the electrophoresis strips'gray scale values of the β-actin over the lumican gene was obtained for ANOVA analysis., Results: β-actin/LUM of normal eye was significantly higher than that of POAG and POAG + HM eyes (P < 0.01), but there was no significant difference between POAG and POAG + HM eyes (P > 0.05)., Conclusions: Differentially expressed lumican between POAG and control groups identified in this study have not been previously investigated for their role in the pathogenesis of POAG and thus are novel factors for further study of the mechanism of the disease and for their possible use as diagnostic markers.

Objective: To investigate the opsin expression in form-deprived and defocus myopia in guinea pig and to study the relationship between the opsin expression and the experimental myopia., Methods: Fifty guinea pigs were randomized into form-deprived group, defocus group (n = 20 in each group) and normal group (n = 10). Guinea pigs in form-deprived group wore a diffuser RGP on one eye since one week after birth. Those in defocus group wore -4.00 D RGP on one eye. The contralateral eyes wore 0 D RGP were used as the control. Refraction, axial length and depth of vitreous cavity were measured after 1 and 2 weeks. Animals were sacrificed and the retina were dissected at 10:00 - 12:00 AM. The level of opsin and its mRNA were measured by Western-blot and real-time PCR, respectively., Results: Two weeks after the experiment, the refraction in form-deprived group and defocus group were (-4.00 ± 0.87) and (-2.00 ± 1.17) D respectively, which were significant different compared with contralateral eyes or normal control group (F = 203.98, 88.66, P < 0.05). These also accompany with increase of axial length and depth of vitreous cavity in form-deprived group and defocus group. Expression of S-opsin mRNA were increased both in form-deprived and defocus groups and the ratios of S-opsin mRNA/β-actin expression were 0.752 ± 0.05 and 1.117 ± 0.13 in two weeks treatment, which were significant different from contralateral eyes (the ratios of S-opsin mRNA/β-actin expression were 0.536 ± 0.04 and 0.772 ± 0.10.t = 6.10, 6.28, P < 0.05). Similar findings were also demonstrated in the expression of L-opsin mRNA, which were increased in form-deprived group and defocus group (the ratios of L-opsin mRNA/β-actin expression were 0.42 ± 0.01) compared with contralateral eyes (the ratios were 0.24 ± 0.0 and 0.34 ± 0.04. t = 6.30, 4.93, P < 0.05) after two weeks experiment. The western-blot results also indicated the high expression of S-opsin and L-opsin level compared to contralateral eyes in form-deprived and defocus groups., Conclusions: Cone might be the detector receiving the signal of form-deprivation and defocus. Changes of opsin expression might play a role in the occurrence of experimental myopia in guinea pig.

Objective: To explore the expression of cyclic guanine monophosphate (cGMP) and the ultrastructure change in retina of guinea pig with form-deprivation myopia and the underlying mechanisms., Methods: Three-weeks-old guinea pigs were distributed in 3 groups: an untreated group (Group I), a myopia 2-weeks group (Group II) and a myopia 3-weeks group (Group III), animals underwent monocular form-deprivation by facemask for 2 and 3 weeks. The right eyes were deprived and the left eyes were self-controlled. The refraction and axial length of the eyes was measured. Retina was observed by electron microscope. The expression of cGMP was detected by radioimmunochemistry., Results: Deprived eyes in guinea pig showed significant development of myopia, the refraction and axial length was increased. The pathological changes in ultrastructure of retina were aggravated with the development of myopia. The expression of cGMP was significantly up-regulated in the deprived eyes compared with self-control eyes(P<0.05)., Conclusion: Form-deprivation can up-regulate the expression of cyclic GMP, which might play an important role in the development of myopia.

Objective: To study effects of vitreous injecting M(1)-selective muscarinic antagonist, pirenzepine, on expression of M(1) and M(4) receptor in retina, choroid, sclera and iris-ciliary body of guinea pig with form-deprived myopia., Methods: Twenty-four 1 - 2 week-old pigmented guinea pigs were randomly divided into four groups. Group1: normal control (N) (n = 6); group 2: simple form-deprived myopia (FDM) (n = 6); group 3: drug control (S) (n = 6); group 4: pirenzepine (P) (n = 6). Expression changes of M(1) and M(4) muscarinic receptors at mRNA level were detected by semi-quantitative RT-PCR in retina, choroid, sclera and iris-ciliary body., Result: 1. After 21 days' treatment, FDM group produced relative myopia of -4.92 D and an axial length of 0.29 mm with significance (P < 0.001), compared with N group. Compared with group S, the relative refractive error in group P was +0.88 D, and axial length decreased 0.30 mm with respectively significance (P < 0.001). Differences in refractive error between group S and group FDM were not significant, but in axial length were significant (0.08 mm vs. 0.29 mm) (P < 0.05). 2. Semi-quantitative RT-PCR: M(1) and M(4) mRNA expression showed no significant differences in the retina, choroid and iris-ciliary body of group P compared with group S (P > 0.05). Of interest, in the posterior sclera, mRNA expression of group P was significantly greater than that of group S for the M(1) (P < 0.05) and M(4) subtypes (P < 0.05). The M(1) and M(4) subtype in group P was increased by +19.16% and +64.29% respectively., Conclusion: M(1)-selective muscarinic antagonist, pirenzepine, can effectively inhibit form-deprived myopia in guinea pig. M(1) and M(4) subtype in sclera and their cholinergic signaling may participate in muscarinic antagonist inhibition of myopic development.

Objective: To observe the expressions of the collagen , matrix metalloproteases-2 (MMP-2), and tissue inhibitor of matrix metalloproteinase-2 (TIMP-2) in the posterior sclera of newborn guinea pigs with negative lens-defocused myopia., Methods: Newborn guinea pigs were monocularly defocused by -10D lens. After 4 weeks of defocus, the eyes were removed to provide posterior scleral samples for detection. Expression of collagen was detected by immunohistochemistry on frozen sections of guinea pig sclera, and the protein levels of MMP-2 and TIMP-2 were evaluated by Western blot., Results: Immunohistochemical analysis indicated that the expressions of collagen and TIMP-2 were significantly lower and the expression of MMP-2 was significantly higher in the posterior sclera in the defocused eyes than in the contralateral eyes (all P < 0.01). However, all these indicators were not significantly different between the contralateral eyes and normal control eyes (all P > 0.05). In the defocused animals, the refraction of defocused eyes was positively correlated with the expression levels of collagen (r = 0.79, P < 0.01) and TIMP-2 (r = 0.74, P < 0.05) and was negatively correlated with the expression level of MMP-2 (r = -0.78, P < 0.01) in posterior sclera., Conclusion: Alteration of extracellular matrix in the posterior sclera, probably participated by MMP-2, may exist during the development of defocus-induced myopia.

Objective: To explore the temporal expression of retinal-choroidal transforming growth factor-beta2 (TGF-beta2) in form-deprived myopia (FDM) chick eyes and study the effect of an inhibitor (disulfiram, DSF) of retinoid acid (RA) synthesis on refractive development and the expression of TGF-beta2., Methods: Ninety new hatched white leghorn chicks were divided randomly and equally into 3 groups: unilateral occluded with frosted goggles (Group A); unilateral intravitreal injection of 4 mmol of the non-specific aldehydedehydrogenase inhibitor disulfiram with further treatment with goggles (Group B); unilateral intravitreal injections of 4 mmol of disulfiram without further treatment with goggles (Group C). Refraction and axial length were measured on 1, 7 and 14 days after treatment. Expression levels of TGF-beta2 and TGF-beta2 mRNA in the retinal-choroid layer were analyzed by immunohistochemistry and real-time RT-PCR., Results: In Group A, the form-deprived eyes made by goggles developed myopia (P<0.05 on day 1, P<0.01 on days 7 and 14, compared with the contralateral eyes) with a lengthening of the axial length (P<0.01 on days 7 and 14, compared with the contralateral eyes), as well as a lower level of TGF-beta2 expression (P<0.01 on days 7 and 14, compared with the contralateral eyes). In Groups B and C, there was no statistically significant difference in refraction and axial length between treated and contralateral eyes (P>0.05) with TGF-beta2 mRNA level growing on day 7 and decreased on day 14 in group B and decreased on day 1, increased on days 7 and 14 in Group C (P<0.01, compared with the contralateral eyes). Immunohistochemistry showed that the expression of TGF-beta2 was mainly changed in the outer part of photoreceptor layer and retinal pigment epithelium (RPE) layer., Conclusion: TGF-beta2 mRNA level decreased in FDM eyes. Disulfiram can up-regulate the level of TGF-beta2 mRNA expression in the posterior retinal-choroid, and inhibit the elongation of axial length and refractive error made by frosted goggles as well. Disulfiram which inhibits the synthesis of retinoid acid may suppress deprivation myopia by up-regulating the expression level of TGF-beta2 mRNA.

Objective: To investigate the effect of regulation of VIPhybrid, an unselective antagonist of vasoactive intestinal peptide receptors (VIPR), on the formation and development of form deprivation myopia (FDM) in chick and the expression of protein and mRNA of VIP on the retina and choroids of in chicks., Methods: Seventy-two 1-day-old yellow healthy leghorn chicks were assigned into 6 groups (12 in each group). Eyes in Group I were covered on the right as a blank control group. Eyes in GroupII were those eyes having been injected with 20 microL saline into vitreous cavity and then covered as a negative control group. Eyes in GroupIII,IV and V were injected with 20 microL VIPhybrid with low (3*10(-12) mol/L), middle (3*10(-10) mol/L) and high (3*10(-8) mol/L) dosage into vitreous cavity and then covered as experimental groups. The above groups had been continuously covered for 1 week. Eyes in Group VI were uncovered and uninjected as a normal control group. Diopter was detected using retinoscopic refraction. The eyeball axis was determined using ophthalmological ultra-A. The expression of protein and mRNA of VIP on retina-choroids-sclera were investigated by SP immunohistochemistry staining and RT-PCR., Results: Form deprivation for 1 week induced high myopia eyes and elongated eyeball axis in GroupI and GroupII, and there was no difference between the 2 groups (P>0.05). The diopter and eyeball axis were significantly reduced in Group III, IV, and V as compared with Group I and II (P<0.01), but the diopter was higher and the eyeball axis was longer than those of Group VI. The diopter and eyeball axis had negative correlation with the concentration gradient of VIPhybrid. The expressions of protein and mRNA of VIP in Group III, IV, and V were down-regulated as compared with those of Group I and I I(P<0.01)and also down-regulated with the increase of concentration of VIPhybrid., Conclusion: VIPhybrid can decrease the development of FDM in chicks, which may provide a new pathway for drug therapy of myopia in human beings.

Purpose: To investigate the rhodopsin expression in form-deprived and defocus myopia in guinea pig and study the relationship between the rhodopsin expression and experimental myopia., Methods: Fourty guinea pigs were randomized into the form-deprived group and the defocus group (n = 20). Guinea pigs in the form-deprived group wore a diffused (rigid glass-permeable contact lens (RGP) on one eye since one week after birth. Those in defocus group wore a -4 D RGP on one eye. The contralateral eyes were left as control. Refraction, axial length and depth of vitreous cavity were measured after 1 and 2 weeks respectively. Retina were dissected at 10-12 o'clock in the morning. The level of rhodopsin and its mRNA were observed through Western-blot and real-time PCR respectively., Result: There is no difference between form-deprived group, defocus group and control groups (except refraction in form-deprived group). One week later, there is no difference between the form-deprived group, the defocus group and the control groups (except refraction in form-deprived group). Two weeks later, eyes in the form-deprived group and the defocus group became myopic. Its axial length lengthened and depth of vitreous cavity appeared deep. The form-deprived groups showed an increased expression of rhodopsin and its mRNA compared to the control groups. There is no difference between the defocus group and the control groups., Conclusion: Expression of rhodopsin might involve formation of form-deprived myopia, but has less influence on defocus myopia.

Objective: To investigate the expression of 5 muscarinic receptor subtypes in the scleral tissue of immature guinea pigs., Methods: The scleral tissue was collected from six 2-week-old pigmented guinea pigs to determine mRNA expressions of the muscarinic receptors with RT-PCR. Immunofluorescence was used to observe the protein expressions of the 5 muscarinic receptor subtypes., Results: The mRNAs of the 5 muscarinic receptor subtypes were all detected in the scleral tissue, and the mRNA expression was the highest for M1 subtype. Green fluorescence of M1 to M5 subtypes surrounding the fibroblast nuclei were found in the scleral matrix using laser confocal microscopy., Conclusion: Five muscarinic receptor subtypes are present in the scleral tissues of immature guinea pigs, indicating the involvement of the muscarinic receptors in eye growth regulation.

Objective: To explore the relationship between melanin synthesis and the congenital high myopia of albino guinea-pigs., Methods: Twelve albino guinea-pigs and 12 pigmented guinea-pigs of 220~250 grams (aged 5~6 weeks) were chosen at random. The eyes were examined with retinoscopy, A-scan ultrasonography and vernier caliper. The retinal structures were examined with light and electronic microscope., Results: The diopter was -19.17 D in albino guinea-pigs and +0.63 D in pigmented guinea-pigs on average. Compared with the pigmented guinea-pigs, the axial dimensions of the albino guinea-pigs were elongated. There was significant difference between the albino guinea-pigs and the pigmented guinea-pigs. The retinal thickness, pigment granules and membrane disc of the outer segment of the visual cells decreased in the albino guinea-pigs, and the membrane disc space became narrow. The normal retinal thickness, plenty of pigment granules , membrane disc and wide membrane disc space could be observed in the pigmented guinea-pigs., Conclusion: Albino guinea-pigs have high myopia, and pigmented guinea pigs have light hyperopia. There are structural differences in the retina between albino guinea-pigs and pigmented guinea-pigs. The abnormity of albino guinea-pigs provides optical foundation for its high myopia.

Objective: To investigate the expression of cone opsins in form-deprived myopia (FDM) of guinea pig., Methods: Twenty-eight pigmented guinea pigs aged one-week were randomly divided into two groups: FDM group (n = 14) and control group (n = 14). White translucent vinyl diffuse attached to one randomly selected eye was used to deprive eyes of form-vision in FDM group. RT-PCR and immunohistochemistry were performed to compare the opsin mRNA expression and spatial density of photoreceptor opsin in the ventral, central and dorsal retinal areas of two groups using antibody against short and medium-wave-length-sensitive cone opsin. Slides were viewed using Leica confocal microscope and Leica light microscope., Results: The distribution of opsin across the guinea pig retinae as determined by antibody labeling of cone opsin was asymmetric, with the dorsal retina dominated by M-opsin, and the ventral retinae by S-opsin. But the ventral area also showed positive staining for the M-opsin. Opsin spatial density decreased with increasing retinal eccentricity for both M and S opsins. The spatial density of S-opsin decreased most steeply for eccentricity up to one-third distance from optic disc to retinal edge. The spatial density of M-opsin gradually decreased with eccentricity. The expression of spatial density of M-opsin was higher than that of S-opsin in all three regions. The expression of density of S-opsin in normal control eye is as follow: (805.0 +/- 203.3) mm(-2) (ventral); (100.0 +/- 57.7) mm(-2) (dorsal); (1637.2 +/- 314.1) mm(-2) (Central). FDM eye: (640.9 +/- 196.8) mm(-2) (ventral); (1016.7 +/- 144.6) mm(-2) (central); (70.9 +/- 30.8) mm(-2); where The expression of spatial density of M-opsin in normal control eye are: (946.2 +/- 388.5) mm(-2) (dorsal); (1666.7 +/- 137.8) mm(-2) (central); (175.0 +/- 100.9) mm(-2) (ventral). FDM eye: (1436.7 +/- 366.0) mm(-2) (dorsal); (2780.0 +/- 180.5) mm(-2) (central); (318.2 +/- 172.7) mm(-2) (ventral). The results of RT-PCR examination showed that the relative optical density (OD) value of M-opsin and S-opsin are: 1.06 +/- 0.07 (FDM eye), 0.51 +/- 0.10 (control eye), and 0.70 +/- 0.07 (FDM eye), 1.25 +/- 0.06 (control eye) respectively. The expression of both opsins in FDM eyes was significant differences compared with control (P < 0.05)., Conclusion: FDM can increase the expression of M-opsin and decrease the S-opsin expression in guinea pig. cone opsins may play a role in the development of myopia.

Objective: The aim of this study was to identify the presence of muscarinic acetylcholine receptors-I (M1 receptor) in human retinal pigment epithelium (RPE) in order to determine the role of M1 receptor in the maintenance of function of RPE and its role in the occurrence and development of myopia., Methods: The 3rd-5th passages of RPE cells established in our laboratory were used in the present study. Reverse transcription-polymerase chain reaction (RT-PCR) was used to detect mRNA expression of M1 receptor in cultured RPE. Immunocytochemistry was used to detect M1 receptor protein in the RPE cells., Results: Cultured RPE demonstrated mRNA expression of M1 receptor in RT-PCR. Protein of M1 receptor was presented in the RPE under immunocytochemistry., Conclusions: This study demonstrated the presence of M1 receptor in human RPE at both mRNA and protein levels. M1 receptor plays an important role in the maintenance of function of RPE. Injection of M1 receptor antagonist into the vitreous can delay the occurrence and inhibit the development of myopia, which is possibly related to the inhibition of RPE cells function.

Objective: To study the apoptosis of retina and the expression of c-myc protein in form-deprivation myopia., Methods: Two-day-old chickens were sutured with right eyelid for 4, 8 and 12 weeks. After measurement of refracation, the eyeballs were observed by light microscope and taken photos. Retinal apoptotic cells were measured by TUNEL staining and flow cytometry. C-myc protein were examined by immunohistochemistry and flow cytometry., Results: Lacquer crack lesions were found in sutured eyes at 12 weeks. Apoptotic cells were observed in retinal outer and inner nuclear layer of the sutured eyes at 12 weeks and obvious peak of apoptosis was observed in sutured eyes at 12 weeks. The expression of c-myc protein was significantly more than control eyes at 8 and 12 weeks., Conclusion: The apoptosis of retinal was present in form-deprivation myopia with the degeneration of retina. C-myc protein plays an important role in retinal apoptosis of myopia.

Objective: To investigate the dynamic expression and significance of vasoactive intestinal peptide receptor 2 (VIPR2) on retina-choroid-clera in high myopia., Methods: Twenty-one yellow chicks of 1 day old were used in the research. The right eyes were the experimental group, covered continuously for 1 week, 2 weeks and 4 weeks respectively. The left eyes were not covered as the normal control group. Both groups were detected diopter degrees using retinoscopic refraction, determinated eyeball axis using ophthalmology ultra-A, and investigated VIPR2 expression on retina-choroid-sclera in both groups at three stages by SP immunohistochemical staining., Results: The experimental eyes changed from hypermetropia at pre-experiment to high myopia during the experiment stages, and the diopter degrees were deeper and eyeball axis was longer along with the period of being covered. Both groups had strong expression of VIPR2 on photoreceptor-outer segment of the retina and choroids. The expression was down-regulated with the time in both groups. Compared with the control group, VIPR2 expression of the experimental group was significantly up-regulated (P < 0.05)., Conclusion: Form deprivation could induce high myopia. The expression of VIPR2 existed on photoreceptor-outer segment of the retina and choroids. VIPR2 may play an important role on the formation and development of myopia.

To investigate the association between variations of ZFP161 gene and high myopia, A total of 204 probands with simple high myopia(< or = -6.0 dipoters) were collected while 116 normal persons from different families without high myopia or related disease were used as controls. Genomic DNA was prepared from the peripheral leucocytes. The coding sequences of ZFP161 gene in 320 subjects were analyzed by using exon-by-exon PCR-heteroduplex-SSCP analysis. Identification of the Variations by cloning and sequencing, combinated with controls and family analysis, was used to disclose the correlation between ZFP161 gene and high myopia. A mutation of ZFP161 gene was identified as an insertion of AT before the 58th nucleotide of intron 1 (IVS1 58-59)(1/204) and a variation of ZFP161 gene was identified as a heterozygous C to A of the 168th nucleotide in exon 2 (Codon56, GCC-->GCA, Ala56Ala). Ala56Ala is a non-sense mutation identified in 5 of the 204 patients and 3 of 116 controls. No evidence shows that these variations are responsible for high myopia.

Objective: To construct a chick model of form-deprivation myopia (FDM) to investigate the effect of nitric oxide (NO) on FDM., Methods: FDM was induced in 60 one-day white leghorn chicks. They were divided into group A and B. One eye was covered randomly, and the other served as control. In each week of the experimental period, the retinoscopic refraction was performed, and the axial length was measured with A-mode ultrasound. The NO concentration of retina and choroid from the control and the experimental eyes was measured using NO detection kit. Change in the expression of iNOS mRNA was measured by RT-PCR. The activity of iNOS was analyzed with immunohistochemistry., Results: Form-deprivation eyes were significantly more myopic than the controls, and the axial length of occluded eyes was significantly longer than that of the controls. Unocclusion attenuated the development of myopia and inhibited the axial elongation. Form-deprivation reduced the NO concentration ,the immunoreactivity of iNOS, and the expression of iNOS mRNA. The gradual restoration of normal vision was found after uncovering the eyes. But the expression of iNOS mRNA was significantly higher than that of the controls at the first week after the unocclusion., Conclusion: Form-deprivation can construct an animal model of myopia. FDM is reversible before the chicks were mature. NO may be involved in the form of FDM.

Objective: To observed the effect of amniotic membrane transplantation (AMT) on expressions of transforming growth factor-beta 1(TGF-beta 1), collagens I, III and fibronectin (FN) in rabbit corneal healing after photorefractive keratectomy (PRK), and investigate the anti-scarring formation mechanism of AMT., Methods: Ten rabbits underwent bilateral PRK to correct 8 diopters of myopia. One eye was randomly transplanted with preserved human amniotic membrane, and the other eye served as the control. The expressions of TGF-beta 1, collagens I, III and FN were studied by immunohistochemistry at 4 weeks after operation., Results: The expression of TGF-beta 1 in corneal epithelium and keratocytes and collegans in anterior stroma was significantly less in AMT group than in the control group. The expressions of collagens III and FN in anterior stroma of ablation area were also significantly less in AMT group than in the control group. The staining of collagen I had no significant difference between the AMT group and the control group., Conclusion: The expressions of TGF-beta 1, collagens III and FN can be suppressed by amniotic membrane after PRK. These data suggest that part of the anti-scarring effect of AMT may be mediated through the suppression of TGF-beta 1, collagens III and FN expression.

With a paired study, 23 factors were investigated in 204 school children aged 9-14 in Taiyuan. The results of analysis of logistic regression showed that there was a close relationship between juvenile myopia and TV-watching distance, myopia in parents, Zn: Cu ratio in hair, N score of EPQ, Pscore of EPQ, and verbal IQ. The relations between myopia and some factors were discussed.