Dermoscopic and clinical predictors of reflectance confocal microscopy patterns of typical nevi on the back and legs: A cross-sectional study.

BACKGROUND: Nevus phenotype is a marker of melanoma risk. In vivo prediction of microscopic pattern is needed to more precisely classify nevi. OBJECTIVE: To identify dermoscopic and clinical predictors of microscopic patterns of typical nevi. METHODS: We used reflectance confocal microscopy (RCM) to classify microscopic patterns of nevi. We prospectively accrued adults presenting for periodic skin screening and imaged, with dermoscopy and RCM, 3 randomly selected nevi from the upper and lower back and lower extremity. RCM patterns were classified into ring, clod, meshwork, and composite types. Logistic regression was used to identify best predictors of RCM pattern. RESULTS: The study included 310 nevi from 112 participants (mean age 44 years; 51 women). Dermoscopic reticular pattern correlated most frequently (59.9%) with RCM ring pattern, dermoscopic globular with RCM composite (56.6%) and RCM clod (35.9%), dermoscopic complex with RCM composite (76.3%), and dermoscopic homogenous with RCM clod (50.8%). Integrating dermoscopic pattern with contour, diameter, color, and anatomic location of nevi improved prediction of microscopic patterns beyond dermoscopy alone. The dermoscopic clinical regression model correctly classified lesions to RCM ring versus RCM clod in 90% and to RCM ring versus RCM composite patterns in 81%. LIMITATIONS: The study was restricted to adults, back and lower extremities, and typical nevi. CONCLUSIONS: Integrating dermoscopic patterns with clinical attributes may improve prediction of microscopic patterns of nevi.

Parkinson disease (PARK) genes are somatically mutated in cutaneous melanoma.

OBJECTIVE: To assess whether Parkinson disease (PD) genes are somatically mutated in cutaneous melanoma (CM) tissue, because CM occurs in patients with PD at higher rates than in the general population and PD is more common than expected in CM cohorts. METHODS: We cross-referenced somatic mutations in metastatic CM detected by whole-exome sequencing with the 15 known PD (PARK) genes. We computed the empirical distribution of the sum of mutations in each gene (Smut) and of the number of tissue samples in which a given gene was mutated at least once (SSampl) for each of the analyzable genes, determined the 90th and 95th percentiles of the empirical distributions of these sums, and verified the location of PARK genes in these distributions. Identical analyses were applied to adenocarcinoma of lung (ADENOCA-LUNG) and squamous cell carcinoma of lung (SQUAMCA-LUNG). We also analyzed the distribution of the number of mutated PARK genes in CM samples vs the 2 lung cancers. RESULTS: Somatic CM mutation analysis (n = 246) detected 315,914 mutations in 18,758 genes. Somatic CM mutations were found in 14 of 15 PARK genes. Forty-eight percent of CM samples carried ≥1 PARK mutation and 25% carried multiple PARK mutations. PARK8 mutations occurred above the 95th percentile of the empirical distribution for SMut and SSampl. Significantly more CM samples harbored multiple PARK gene mutations compared with SQUAMCA-LUNG (p = 0.0026) and with ADENOCA-LUNG (p < 0.0001). CONCLUSIONS: The overrepresentation of somatic PARK mutations in CM suggests shared dysregulated pathways for CM and PD.

Enzymatic MPG DNA repair assays for two different oxidative DNA lesions reveal associations with increased lung cancer risk.

DNA repair is a major mechanism for minimizing mutations and reducing cancer risk. Here, we present the development of reproducible and specific enzymatic assays for methylpurine DNA glycosylase (MPG) repairing the oxidative lesions 1,N6-ethenoadenine (εA) and hypoxanthine (Hx) in peripheral blood mononuclear cells protein extracts. Association of these DNA repair activities with lung cancer was determined using conditional logistic regression with specimens from a population-based case-control study with 96 lung cancer cases and 96 matched control subjects. The mean MPG-εA in case patients was 15.8 units/µg protein (95% CI 15.3-16.3), significantly higher than in control subjects-15.1 (14.6-15.5), *P = 0.011. The adjusted odds ratio for lung cancer associated with a one SD increase in MPG-εA activity (2.48 units) was significantly bigger than 1 (OR = 1.6, 95% CI = 1.1-2.4; *P = 0.013). When activity of OGG1, a different DNA repair enzyme for oxidative damage, was included in the model, the estimated odds ratio/SD for a combined MPG-εA-OGG1 score was 2.6 (95% CI 1.6-4.2) *P = 0.0001, higher than the odds ratio for each single assay. The MPG enzyme activity assays described provide robust functional risk biomarkers, with increased MPG-εA activity being associated with increased lung cancer risk, similar to the behavior of MPG-Hx. This underscores the notion that imbalances in DNA repair, including high DNA repair, usually perceived as beneficial, can cause cancer risk. Such DNA repair risk biomarkers may be useful for risk assessment of lung cancer and perhaps other cancer types, and for early detection techniques such as low-dose CT.

Low integrated DNA repair score and lung cancer risk.

DNA repair is a prime mechanism for preventing DNA damage, mutation, and cancers. Adopting a functional approach, we examined the association with lung cancer risk of an integrated DNA repair score, measured by a panel of three enzymatic DNA repair activities in peripheral blood mononuclear cells. The panel included assays for AP endonuclease 1 (APE1), 8-oxoguanine DNA glycosylase (OGG1), and methylpurine DNA glycosylase (MPG), all of which repair oxidative DNA damage as part of the base excision repair pathways. A blinded population-based case-control study was conducted with 96 patients with lung cancer and 96 control subjects matched by gender, age (±1 year), place of residence, and ethnic group (Jews/non-Jews). The three DNA repair activities were measured, and an integrated DNA repair OMA (OGG1, MPG, and APE1) score was calculated for each individual. Conditional logistic regression analysis revealed that individuals in the lowest tertile of the integrated DNA repair OMA score had an increased risk of lung cancer compared with the highest tertile, with OR = 9.7; 95% confidence interval (CI), 3.1-29.8; P < 0.001, or OR = 5.6; 95% CI, 2.1-15.1; P < 0.001 after cross-validation. These results suggest that pending validation, this DNA repair panel of risk factors may be useful for lung cancer risk assessment, assisting prevention and referral to early detection by technologies such as low-dose computed tomography scanning.

N-methylpurine DNA glycosylase and OGG1 DNA repair activities: opposite associations with lung cancer risk.

Only a minority of smokers develop lung cancer, possibly due to genetic predisposition, including DNA repair deficiencies. To examine whether inter-individual variations in DNA repair activity of N-methylpurine DNA glycosylase (MPG) are associated with lung cancer, we conducted a blinded, population-based, case-control study with 100 lung cancer case patients and 100 matched control subjects and analyzed the data with conditional logistic regression. All statistical tests were two-sided. MPG enzyme activity in peripheral blood mononuclear cells from case patients was higher than in control subjects, results opposite that of 8-oxoguanine DNA glycosylase (OGG1) DNA repair enzyme activity. For lung cancer associated with one standard deviation increase in MPG activity, the adjusted odds ratio was 1.8 (95% confidence interval [CI] = 1.2 to 2.6; P = .006). A combined MPG and OGG1 activities score was more strongly associated with lung cancer risk than either activity alone, with an odds ratio of 2.3 (95% CI = 1.4 to 3.6; P < .001). These results form a basis for a future panel of risk biomarkers for lung cancer risk assessment and prevention.

Local injury of the endometrium induces an inflammatory response that promotes successful implantation.

OBJECTIVE: To study whether an injury-induced inflammation might be the mechanism underlying the favorable effect of endometrial biopsy on the implantation rate in in vitro fertilization (IVF) patients. DESIGN: Controlled clinical study. SETTING: A medical center IVF unit and a research institute. PATIENT(S): Women undergoing IVF who had previous failed treatment cycles. INTERVENTION(S): Endometrial samples were collected from two groups of patients on day 21 of their spontaneous menstrual cycle. The experimental, but not the control group underwent prior biopsy treatment on days 8 or/and 11 to 13 of that same cycle. MAIN OUTCOME MEASURE(S): Abundance of immune cells, cytokines/chemokines level, correlation between these parameters and pregnancy outcome. RESULT(S): A statistically significantly higher amount of macrophages/dendritic cells (HLA-DR+ CD11c+ cells) and elevated proinflammatory cytokines, tumor necrosis factor-α (TNF-α), growth-regulated oncogene-α (GRO-α), interleukin-15 (IL-15), and macrophage inflammatory protein 1B (MIP-1B), were detected in day-21 endometrial samples of the experimental group. A direct stimulatory effect of TNF-α on MIP-1B, GRO-α, and IL-15 messenger RNA (mRNA) expression was demonstrated. A positive correlation was found between the levels of macrophages/dendritic cells, MIP-1B expression, and TNF-α expression and the pregnancy outcome. CONCLUSION(S): A biopsy-induced inflammatory response may facilitate the preparation of the endometrium for implantation. Increased MIP-1B expression could possibly serve for prediction of implantation competence.

Development of an enzymatic DNA repair assay for molecular epidemiology studies: distribution of OGG activity in healthy individuals.

While the role of reduced DNA repair in susceptibility to hereditary cancers is well established, its role in sporadic cancer is less understood. One of the reasons is the lack of specific DNA repair assays that are suitable for epidemiology studies. Here we describe the development of the OGG test, an epidemiology-grade enzymatic assay for the activity of the base excision repair enzyme 8-oxoguanine DNA glycosylase, in protein extracts prepared from human blood cells. The assay is robust and reproducible, with a coefficient of variation of 10%. Using the OGG test we determined OGG activity in 120 healthy individuals. Our results show an inter-individual variation of 2.8-fold in OGG activity, from 3.6 up to 10.1units/microg protein, with a mean value of 7.2units/microg protein. There was no significant difference in OGG activity between males and females, or between smokers and non-smokers. Interestingly, there was a gender-specific effect of age: OGG activity was slightly but significantly lower in males older than the age of 55 years compared to younger males, but not in females at the same age groups. Analysis of OGG1 mRNA by quantitative real-time RT-PCR showed a group trend of an increase in OGG enzymatic activity with increasing mRNA expression, but the correlation between activity and mRNA in individuals was poor, indicating the importance of factors other than mRNA expression. The OGG test described is expected to be useful in studying the role of 8-oxoguanine repair in cancer, as recently demonstrated for non-small cell lung cancer [T. Paz-Elizur, M. Krupsky, S. Blumenstein, D. Elinger, E. Schechtman, Z. Livneh, J. Natl. Cancer Inst. 95 (2003) 1312-1319]. In addition, it may serve as a paradigm for the development of additional functional DNA repair tests, which are needed in order to gain further insight into the role of DNA repair in cancer risk and pathology.

Cloprostenol, a prostaglandin F(2alpha) analog, induces hypoxia in rat placenta: BOLD contrast MRI.

Blood oxygen level dependent (BOLD) contrast was used to monitor hypoxia induced by cloprostenol, a prostaglandin F(2alpha) (PGF(2alpha)) analog, in the rat embryo-placental unit (EPU). It is shown that administration of cloprostenol (0.025 mg/rat) at mid-gestation (day 16) reduced EPU oxygenation, as detected by BOLD contrast MRI, in correlation with induction of vascular endothelial growth factor (VEGF) gene (Vegfa) expression in the corresponding placenta (r = 0.56, p = 0.03). Elevated VEGF mRNA expression in response to cloprostenol treatment was also observed at early gestation (day 9) in the forming placenta (p = 0.04) and uterus (p = 0.03). Cloprostenol increased the expression levels of endothelin-1 (ET-1) gene (Edn1) (p = 0.03) and its corresponding peptide (p = 0.02) in the forming placenta, as well as the expression of the endothelin receptor type A (ETA) gene (Ednra) in both the forming placenta (p = 0.009) and the uterus (p = 0.01). The levels of the endothelin receptor type B (ETB) gene (Ednrb) were not affected in response to cloprostenol, but a significant elevation in the expression level of this receptor was observed in the uterus at mid- and late gestation (day 22) (p = 0.04 and 0.01 respectively), suggesting a role for ETB in the vasodilatory status of the pregnant uterus. It is suggested that PGF(2alpha) induces uteroplacental vasoconstriction in the rat, and that ET-1 may take part in mediating this effect, probably via activation of ETA receptor. The uteroplacental vasoconstriction induces hypoxia, as manifested by significant changes in BOLD MRI and by upregulation of VEGF.

Reduced repair of the oxidative 8-oxoguanine DNA damage and risk of head and neck cancer.

An increasing number of studies indicate that reduced DNA-repair capacity is associated with increased cancer risk. Using a functional assay for the removal of the oxidative DNA lesion 8-oxoguanine by the DNA-repair enzyme 8-oxoguanine DNA glycosylase 1 (OGG1), we have previously shown that reduced OGG activity is a risk factor in lung cancer. Here, we report that OGG activity in peripheral blood mononuclear cells from 37 cases with squamous cell carcinoma of the head and neck (SCCHN) was significantly lower than in 93 control subjects, frequency matched for age and gender. Retesting of OGG activity 3 to 4 years after diagnosis and successful treatment of 18 individuals who recovered from the disease showed that OGG activity values were similar to those determined at diagnosis, suggesting that reduced OGG activity in case patients was not caused by the disease. Logistic regression analysis indicated that the adjusted odds ratio (OR) associated with a unit decrease in OGG activity was statistically significantly increased [OR, 2.3; 95% confidence interval (95% CI), 1.5-3.4]. Individuals in the lowest tertile of OGG activity exhibited an increased risk of SCCHN with an OR of 7.0 (95% CI, 2.0-24.5). The combination of smoking and low OGG was associated with a highly increased estimated relative risk for SCCHN. These results suggest that low OGG is associated with the risk of SCCHN, and if confirmed by additional epidemiologic studies, screening of smokers for low OGG activity might be used as a strategy for the prevention of lung cancer and SCCHN.

[Diabetic retinopathy following cataract surgery].

BACKGROUND: Approximately 20% of patients undergoing cataract surgery have diabetes mellitus. AIM: To evaluate the course of diabetic retinopathy after cataract surgery. METHODS: Diabetic patients with no or mild to moderate preoperative diabetic retinopathy were included and classified into 4 groups (A-D): A--The course of retinopathy, B--macular edema, C--the effect of voltaren ophtha eye drops and D--systemic glycemic control. Group E included eyes with previous laser treatment for proliferative retinopathy. Clinical and angiographic retinal findings were scored before and after surgery. Progression was defined as an increase in the retinal score. In groups A, C, D and E the non-operated eye served as a control. In group B, the eyes of nondiabetic patients who had undergone cataract surgery served as a control. RESULTS: Retinopathy was stable in 66% and progressed in 34% (p < 0.005). Progression occurred during the first 6 postoperative months in 84%. Preoperative retinopathy was a risk factor for progression. Good visual acuity was achieved in 67% and was correlated with: preoperative retinopathy and postoperative deterioration. Macular edema was found in 50% of eyes compared to 8% of the controls (p < 0.005). Its development was correlated with preoperative retinal status. Twenty six eyes were treated with voltaren eye drops and 24 with placebo. Progression of macular edema was seen less often in eyes treated with voltaren (p < 0.001). Deterioration of retinopathy was less common in cases when HbA1C was equal to or lower than 7.5 mg%. CONCLUSIONS: Close retinal follow-up after cataract surgery is recommended, especially in patients with preoperative diabetic retinopathy. Systemic control of diabetes and antiinflammatory eye drops may improve surgical results.

Magnetic resonance imaging reveals functional diversity of the vasculature in benign and malignant breast lesions.

BACKGROUND: Tumor perfusion through the microvascular network can be imaged noninvasively by dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). The objective of the current study was to quantify the microvascular perfusion parameters in various human breast lesions and to determine whether they varied between benign lesions and malignancy and whether they were altered with increased invasiveness. METHODS: Perfusion parameters in 22 benign fibrocystic changes, 15 ductal carcinomas in situ (DCIS), 30 infiltrating ductal carcinomas (IDC), and 22 fibroadenomas were measured using high-resolution DCE-MRI. Pixel-by-pixel image analysis yielded parametric images of two perfusion indicators: the influx transcapillary transfer constant (k(trans)) and the efflux transcapillary rate constant (k(ep)). Correlations of lesion type and perfusion parameters were calculated using Spearman correlation. Logistic regression analysis evaluated the best predictors of the kinetic parameters that differentiate between IDC and benign lesions. RESULTS: The perfusion parameters exhibited a progressive increase from benign fibrocystic changes to DCIS and IDC, with a significant correlation between lesion type and the parameters' values (range of correlation coefficients, 0.56-0.76; P < 0.0001). In addition, k(trans) increased from low-grade DCIS to high-grade DCIS. Fibroadenomas were characterized uniquely by high k(trans) but low k(ep). Stepwise logistic regression selected k(trans) as the best predictor for distinguishing benign fibrocystic changes from IDC, yielding 93% sensitivity and 96% specificity. CONCLUSIONS: The microvascular perfusion parameters in breast lesions were elevated with invasiveness. Quantification of these parameters using high-resolution DCE-MRI was helpful for differentiating between breast lesions and should improve breast carcinoma diagnosis.

Repair of the oxidative DNA damage 8-oxoguanine as a biomarker for lung cancer risk.

DNA repair has a major role in suppressing the rate of accumulation of mutations. Therefore, variations in DNA repair are likely to play an important role in determining cancer risk. While there is compelling evidence that defects in DNA repair cause high predisposition to several hereditary cancers, there is a paucity of data on the role of DNA repair in sporadic cancers. We present our approach of using functional DNA repair tests, rather than gene polymorphism, to study the potential of DNA repair enzymes to serve as biomarkers for lung cancer risk. We have previously developed a functional DNA repair blood test for the enzymatic repair of the oxidative DNA lesion 8-oxoguanine, and found that reduced OGG activity is a risk factor in non-small cell lung cancer. Moreover the combination of smoking and low OGG activity was associated with a greatly increased lung cancer risk (Paz-Elizur et al, JNCI 95 (2003) 1312-1319). The use of OGG activity as a potential biomarker for lung cancer risk is validated in collaboration with the M. D. Anderson Cancer Center, under the sponsorship of the Associate Members Program of the Early Detection Research Network (EDRN, NCI, NIH).

DNA repair activity for oxidative damage and risk of lung cancer.

BACKGROUND: Although smoking is a major cause of lung cancer, only a proportion of smokers develop lung cancer, suggesting a genetic predisposition in some individuals. Because tobacco smoking is associated with the increased formation of DNA lesions, including those induced from oxidative damage, we investigated whether the activity of the DNA repair enzyme 8-oxoguanine DNA N-glycosylase (OGG), which repairs the oxidative DNA lesion 8-oxoguanine, is associated with lung cancer. METHODS: We conducted a molecular epidemiologic case-control study that included 68 case patients with non-small-cell lung cancer and 68 healthy control subjects, frequency matched for age and sex. Enzymatic OGG activity was determined in protein extracts prepared from peripheral blood mononuclear cells or lung tissue by assaying the cleavage product of a radiolabeled synthetic DNA oligonucleotide containing an 8-oxoguanine residue. Odds ratios (ORs) and 95% confidence intervals (CIs) were determined by conditional logistic regression. All statistical tests were two-sided. RESULTS: OGG activity was lower in peripheral blood mononuclear cells from case patients than in those from control subjects. After adjustment for age and smoking status, individuals in the lowest tertile of OGG activity had an increased risk of non-small-cell lung cancer compared with individuals in the highest tertile (OR = 4.8, 95% CI = 1.5 to 15.9). The adjusted OR associated with a unit decrease in OGG activity was statistically significantly increased (OR = 1.9, 95% CI = 1.3 to 2.8). There was no interaction between OGG activity and smoking status. The estimated relative risk of lung cancer for smokers with low OGG activity was 34- or 124-fold higher for smokers with a low OGG activity of 6.0 or 4.0 U/ micro g protein, respectively, than for nonsmokers with a normal OGG activity of 7.0 U/ micro g protein, illustrating the cumulative effect of low OGG activity and smoking. CONCLUSIONS: Low OGG activity is associated with an increased risk of lung cancer. Although prospective studies are needed to validate the results, they suggest that smoking cessation in individuals with reduced OGG activity might be an effective strategy in lung cancer prevention.

Local injury to the endometrium doubles the incidence of successful pregnancies in patients undergoing in vitro fertilization.

OBJECTIVE: Exploration of the possibility that local injury of the endometrium increases the incidence of implantation. DESIGN: Prospective study. SETTING: Clinical IVF unit. PATIENT(S): A group of 134 patients, defined as good responders to hormonal stimulation, who failed to conceive during one or more cycles of IVF and embryo transfer (ET). INTERVENTION(S): The IVF treatment and ET were preceded by repeated endometrial biopsies, in a randomly selected 45 of a total of 134 patients. MAIN OUTCOME MEASURES: Outcome of IVF-ET treatments. RESULT(S): Transfer of a similar number of embryos (3.4 +/- 1.0 and 3.1 +/- 0.9 in the experimental and control patients, respectively) resulted in rates of implantation (27.7% vs. 14.2%, P =.00011), clinical pregnancy (66.7% vs. 30.3%, P =.00009), and live births per ET (48.9% vs. 22.5%, P =.016) that were more than twofold higher in the experimental group as compared to controls. CONCLUSION(S): These results suggest that IVF treatment that is preceded by endometrial biopsy doubles the chance for a take-home baby.

Comparison of trabeculectomy with mitomycin C with or without phacoemulsification and lens implantation.

PURPOSE: To compare the results of combined trabeculectomy with phacoemulsification and posterior chamber intraocular lens (IOL) implantation to those of trabeculectomy alone using mitomycin C (MMC) application intraoperatively in all cases. PATIENTS AND METHODS: A retrospective comparative study of consecutive patients was conducted on two groups: 102 eyes of 90 patients studied in the combined procedure group, and 33 eyes of 30 patients in the trabeculectomy alone group. RESULTS: Both groups showed a significant decrease in IOP. The combined group had a change from 21.5+/-5.8 mm HG preoperative to 14.73+/-3.44 mm HG postoperative, P=0.0001; the trabeculectomy group changed from 24.2+/-7.5 mm HG preoperative to 12.46+/-3.86 mm HG postoperative, P=0.0001. This represents a 31.5% reduction in IOP in the combined group versus a 48.5% reduction in the trabeculectomy alone group (P=0.0001). The follow-up time was longer in the trabeculectomy group (trabeculectomy group, 22.6+/-13.3 months; combined group, 14.2+/-8.0 months), P=0.0014. There were 97 eyes in the combined group (95%) and 32 eyes (97%) in the trabeculectomy group that had an IOP of less than 20 mm HG at the end of follow up. Postoperatively, the two groups showed similar significant reductions in the number of antiglaucomatous medications used (combined group, 0.82+/-1.0 compared with 2.65+/-0.84 preoperatively, P=0.0001; trabeculectomy group, 0.76+/-1.2 compared with 2.7+/-0.95 preoperatively, P=0.0001). There were no cases of bleb leakage in the combined group and two cases (6%) in the trabeculectomy group. CONCLUSION: The reduction of IOP is significantly larger after trabeculectomy alone than after the combined procedure; however, the functional and anatomical results of the combined procedure of phacoemulsification, posterior chamber IOL implantation, and trabeculectomy with MMC application were as good as those of trabeculectomy alone with MMC.

Microscope-induced retinal phototoxicity in cataract surgery of short duration.

OBJECTIVE: Microscope-induced retinal phototoxicity has been described after prolonged cataract surgery, usually in operations lasting longer than 100 minutes. The purpose of this study was to compare the features of microscope-induced retinal phototoxicity occurring in patients who underwent cataract surgery of short duration and long duration. DESIGN: A retrospective nonrandomized comparative trial. PARTICIPANTS: Thirty-four patients, whose medical records documented the development of phototoxic lesions in the retina as a result of cataract surgery, were divided into two groups: group A with 14 patients whose operating time was 30 minutes or less, and group B with 20 patients whose operating time was greater than 30 minutes. INTERVENTION: All patients underwent either phacoemulsification or extracapsular cataract extraction (ECCE) with implantation of an intraocular lens. RESULTS: The mean operating time was 23.1 minutes (range, 11-30 minutes) in group A, and 60.8 minutes (range, 34-123 minutes) in group B. Phacoemulsification was done more often in group A (P = 0.001) and ECCE in group B (P = 0.0003). A final refraction of +/- 1 D was achieved by 12 eyes (86%) in group A and by 12 eyes (60%) in group B (P = 0.11). The correlation between final refraction and duration of the operation was significant; the closer the final refraction approached to emmetropia, the shorter the duration of surgery (r = 0.53; P = 0.001). Diabetic retinopathy was more common in group A (P = 0.03). CONCLUSIONS: Phototoxic lesions of the retina may occur during cataract surgery even when the duration of the operation is short. The most relevant associated factors found in this study were correction approximating emmetropia and diabetic retinopathy.