ABSTRACT
Objective To measure the tear film lipid layer thickness (LLT) in dry eye patients and investigate the correlations of LLT with ocular surface signs.Methods One hundred and thirty dry eye patients (130 eyes),including 64 meibomian gland dysfunction (MGD) patients and 66 non-MGD patients,were included in this study.LLT,break-up time (BUT),fluorescein staining (FL),Marx's line (ML) score and Schirmer I test were performed and examined.The distribution of LLT in different age groups and the correlations between LLT and other examinations were analyzed.Results There was significant difference in LLT among different age groups (P =0.007),while LLT was not significantly different between male and female in each age group (P ＞ 0.05).LLT was positively correlated with age (r =0.334,P ＜ 0.001) and was not correlated with sex (r =0.107,P =0.226).LLT was positively correlated with upper eyelid ML score (r =0.295,P =0.001) and lower eyelid ML score (r =0.233,P =0.008).There was no significant correlation of LLT with BUT,FL or Schirmer Ⅰ test (all P ＞0.05).In the MGD group,there were positive correlations of LLT with upper eyelid ML score and lower eyelid ML score (all r =0.306,P =0.014),and no correlation of LLT with other examinations (all P ＞ 0.05).In the non-MGD group,there was no correlation of LLT with other examinations (all P ＞ 0.05).In a multivariate linear regression analysis,age and upper eyelid ML score were significantly related to LLT (β =0.254,P =0.005 for age and β =0.207,P =0.022 for upper eyelid ML score) in all dry eye patients.Age was the only factor related to LLT (β =0.382,P =0.002) in the MGD group.Upper eyelid ML score and lower eyelid ML score were higher in the MGD group than the non-MGD subgroup (all P ＜ 0.001).Conclusion LLT is positively correlated with age and ML score in dry eye patients.The measurement of tear film LLT,as an auxiliary examination in the diagnosis of dry eye disease,should be analyzed with the influential factors including age.
ABSTRACT
Background Diabetic retinopathy (DR) is a progressive vision-threatening complication of diabetes mellitus (DM),but its pathogenic mechanism is still unclear.Researches showed that growth arrest-specific gene product 6 (Gas6) /TAM system participates in pathogenesis and development of DR,and stromal-derived factors (SDF) vary in 2-type DM patients.However,whether Gas6/TAM and SDF-1 are associated with DR is below understood.Objective This study was to determine the relationship between the staging of DR and the levels of serum Gas6,SDF-1α and SDF-1β in DM patients.Methods A prospective cohord study was designed in this study.Ninety 2-type DM patients were included in the 3rd Affiliated Hospital of Southern Medical University Hospital from January to August in 2013.The patients were grouped into the non-diabetic retinopathy (NDR) group,background DR group (BDR) and proliferative DR (PDR) group,with 30 for each group.Thirty normal volunteers were enrolled in the same hospital and same period.The periphery blood 2 ml was collected from all the subjects under the consent inform.The levels of serum Gas6,SDF-1α and SDF-1β were assayed by ELISA,and leukocytes,neutrophils,plasma triglycerides (TG),total cholesterol (CHOL),high density lipoprotein cholesterol (H DL-C) and low density lipoprotein cholesterol (LDL-C) levels were detected and compared among the 4 groups.The correlations of serum Gas6,SDF-1 α and SDF-1 β changes with blood inflammatory cells and blood lipid were analyzed.Results The plasma CHOL concentrations were 4.93(4.14,5.44),5.02(4.35,5.69),4.54(3.85,5.93) and 5.99(5.11,6.89)mmol/L in the normal control group,NDR group,BDR group and PDR group,respectively,and the blood CHOL concentrations were significantly higher in the PDR group than those of the normal control group,NDR group,BDR group (P =0.002,P =0.007,P =0.006).White blood cell counts in the normal control group,BDR group were higher than those of the PDR group (P =0.034,P =0.015),neutrophil counts in the BDR group were higher than those of the PDR group (P =0.024),HDL-C in the NDR group was higher than that in the PDR group (P =0.032).LDL-C in the PDR group was higher than that in the normal control group.Compared with the normal control group,serum Gas6 levels were significantly lower in the NDR group and BDR group (P =0.048,P =0.006),and the serum Gas6 level showed an insignificant increase in the PDR group in comparison with BDR group (P =0.297).Serum SDF-1α levels in the PDR group was significantly higher than that in the BDR group (P =0.033) ;serum SDF-1β levels in the PDR group,BDR group were significantly higher than that in the NDR group (P =0.011,P =0.008) and normal control group (P =0.030,P =0.002).Weaker positive correlation was observed between the serum Gas6 and CHOL,TG,LDL-C levels (r=0.285,r=0.200,r=0.241,all at P＜0.05),between SDF-1α and SDF-1β (r=0.190,P＜0.05) as well as between SDF-1β and white blood cell (r=0.183,P＜0.05).Serum Gas6 served as dependent variable,while white blood cell,neutrophil,CHOL,TG,HDL-C,LDL-C,SDF-1α,SDF-1β served as independent variables,multiple stepwise regression analysis showed Gas6 =170.791 + 5.283CHOL (F =5.021,P =0.027).Conclusions Serum Gas6,SDF-1α and SDF-1β probably participate in the development of DR in 2-type diabetic patients.Gas6,SDF-1 α,SDF-1 β may play roles by affecting blood glucose level,angiogenesis,inflammatory cells and blood lipid metabolism.