Association between incidence of fatal intracerebral hemorrhagic stroke and fine particulate air pollution

OBJECTIVE@#Few studies investigating associations between fine particulate air pollution and hemorrhagic stroke have considered subtypes. Additionally, less is known about the modification of such association by factors measured at the individual level. We aimed to investigate the risk of fatal intracerebral hemorrhage (ICH) incidence in case of PM (particles ≤ 2.5 μm in aerodynamic diameter) exposure.@*METHODS@#Data on incidence of fatal ICH from 1 June 2012 to 31 May 2014 were extracted from the acute stroke mortality database in Shanghai Municipal Center for Disease Control and Prevention (SCDC). We used the time-stratified case-crossover approach to assess the association between daily concentrations of PM and fatal ICH incidence in Shanghai, China.@*RESULTS@#A total of 5286 fatal ICH cases occurred during our study period. The averaged concentration of PM was 77.45 μg/m. The incidence of fatal ICH was significantly associated with PM concentration. Substantial differences were observed among subjects with diabetes compared with those without; following the increase of PM in lag2, the OR (95% CI) for subjects with diabetes was 1.26 (1.09-1.46) versus 1.05 (0.98-1.12) for those without. We did not find evidence of effect modification by hypertension and cigarette smoking.@*CONCLUSIONS@#Fatal ICH incidence was associated with PM exposure. Our results also suggested that diabetes may increase the risk for ICH incidence in relation to PM.

Establishment of a Guinea Pig Model of Myopia Induced by Exposing to 530 nm Monochromatic Light / 中国实验动物学报

Objective In the early life period when eyes grow rapidly,visual experience can play an important role in axial growth and refractive development. For instance, depriving the eye of form vision during infancy will accelerate axial growth, resulting in substantial amounts of myopia, called form deprivation myopia (FDM). Similarly, imposing the eye with a negative lens produces compensating myopic growth in many species, called defocus induced myopia (DIM) . As one of the important visual experiences,color vision and its effects on eye growth deserve to be investigated. The purpose of this study was to investigate the effect of 530 nm monochromatic light and establish an innovative model of myopia in guinea pig by exposing to this monochromatic light. Methods Twenty male guinea pigs at 2 weeks old were randomly assigned to two groups (n = 10) . The experimental group was raised under the condition of 330 nm monochromatic light illumination. The control one was bred under white light illumination with 5000 k color temperature. These guinea pigs were raised in a specially designed cage. The light source was provided by specially made LEDs (green: peak value 530 nm and half bandwidth 30 nm; white: color temperature 5000 K) . The illumination parameters of the two groups were identical and the light quantum number was 3 x 10~(-4)μmol·cm~(-2)·s~(-1) . Through measuring,the irradiance value was 0.150 mW·cm~(-2) for green light and 0.247 mW·cm~(-2) for white light approximately. All animals were kept under a 12/12 h light/dark cycle (light: 8 a.m. - 8 p.m. ) ,in the temperature of 22℃ - 26℃ and a relative humidity of 55% -65% . Both groups underwent biometric measurement including refraction,corneal curvature and axial length,etc. before and after twelve weeks treatment. The refraction was examined using a streak rednoscope and trial lenses in a dark room one hour after topically administering a cycloplegic eye drop. The radius of comeal curvature was measured with a keratometer (Topcon OM-4, Japan) and axial components was measured by A-scan ultrasonagraphy ( Opticon Hiscan A/B).Repeated measurements were undertaken. Only the right eye's parameters of each guinea pig were used for analysis. Unpaired (-tests were used in all comparisons between the two groups of eyes with a statistical analysis software (Stata, version 7.0) . Results Before treatment, the refraction of experimental group was 4.6 ± 0.59 D.and that of the control group was 4.63 ± 0.48 D. The axial and vitreous body length was 7.48 ±0.11 mm and 3.16 ±0.07 mm in the experimental group,respectively,and 7.55 ±0.16 mm,3.21 ±0.09 mm in the control. The differences between the biometric parameters of the two groups including refraction, comeal curvature and axial components were not significant ( P > 0.05) . However,after a twelve-week exposure, the variation of refraction in the experimental group was -3.125 ± 0.76 D,and - 1.075 ± 0.71 D was observed in the control group. There was a 2.0 D myopia in the experimental group compared with the control. Axial length grew 0.98 ± 0.13 mm in the experimental group and 0.77 ± 0.22 mm in the control. Vitreous body extended to 0.33 ± 0.14 mm and 0.13 ± 0.14 mm in the two groups, respectively. The refraction of the experimental group shifted more towards myopia ( P < 0.0001) accompanied with a more accelerated speed of axial growth and vitreous body's extension ( P < 0.05) compared with that of the control group. There were no significant differences in the radius of comeal curvature, the depth of anterior chamber and the lens thickness between the eyes of the two groups at the end of the experiment ( P > 0.05) . Conclusion The 530 run monochromatic light can accelerate the prolongation of axial length and vitreous body inducing axial myopia in guinea pigs.

Enlightenment from corneal wound healing for excimer laser refractive surgery / 眼科研究

Wound healing in the human cornea has distinctive characteristics in comparison to most other tissues in the body.The corneal wound healing response is a remarkably complex cascade mediated by cytokines,growth factors,and chemokines.The interactions in the epithelial,stromal,neural,lacrimal gland,immune cells are interwoven in the corneal response to injury.Corneal epithelial cells and basement membrane play important roles in this process.However,both of them are usually impaired during the procedures of excimer laser refractive surgery for myopia,hyperopia,or astigmatism,and complications such as overcorrection,undercorrection,regression,refractive instability,and haze may occur after surgery.A complete corneal wound healing process,the biologic and molecular processes that contribute to the healing response,and anomalies that lead to complications are critical for improving the efficacy and safety of excimer laser refractive surgical procedures.