[Analysis of structure and function of meibomian glands in healthy population at different ages].

Objective: To observe the structure and function of meibomian glands in normal population at different ages. Methods: From October 2011 to August 2012, meibomian gland information was collected in healthy volunteers without any symptoms of ocular discomfort, aged more than 5 years. The people were grouped by every 10 years of age. The meibomian gland opening, secretion state and characteristics and Max's line were observed by slit lamp microscopic examination, and the meibomian gland dropouts were examined by noncontact infrared meibomian gland microscopy. The changes of meibomian glands were scored from 0 to 3, 0 for a normal state, 1 for mild abnormality, 2 for moderate abnormality and 3 for severe abnormality. The Mann-Whitney U test was used to compare the meibomian scores between male and female, and between left and right eyes. The correlation of these scores and the age of volunteers was analyzed by the Spearman test. Results: Among all the 100 volunteers, there were 47 males and 53 females, aged from 5 to 83 years (mean, 40.9±22.9). The meibomian gland dropouts were gradually increasing with age, significantly faster after 40 years old (scores for each age group were 2(1), 2(1), 2(1), 2(1), 3(2), 3.5(1.75), 4(3), 6(2). Meibomian gland opening, secretion traits and secretor status gradually became poorer with age, and changes were dramatically fast in the group of 40-49 years of age [scores of this group were 3(1.5), 3(3) and 2(2)], but slowed down after age of 50 years. Moreover, the Max's line position moved to the front gradually with age, with a marked change in the group of 40-49 years of age [scores for each age group were 0(1), 1(1), 2(2), 2(2), 3(2), 2(2), 3(2)], 4 gland changes showed a significantly positive relation to age(r=0.729, 0.635, 0.669, 0.639, 0.470. P<0.01), but not to gender and eye dominance (P>0.05). Conclusions: Meibomian gland opening and meibomian gland secretion become worse with age. The age of 50 years old is the key period for the meibomian gland changes. (Chin J Ophthalmol, 2017, 53: 528-533).

Effect of stenting on patients with chronic internal carotid artery occlusion.

AIM: Effects of carotid artery stenting (CAS) on patients with chronic internal carotid artery occlusion are unknown. METHODS: This study included 21 patients who underwent successful CAS treatment and 41 patients who received optimal medical therapy. Modified Rankin Scale (mRS) and cardiocerebral vascular events were compared between CAS and medical therapy group. RESULTS: The mRS in CAS group was lower than in control group during a 2-year follow up (P<0.05 or 0.01). The combined cerebrovascular events and mortality in study group was lower than in the control group (33.4% vs. 56.1%, P=0.045), but there was no statistically significant difference in the cerebrovascular event (28.6% vs. 46.3%, P=0.088) or mortality rate (4.8% vs. 9.8%, P=0.247) between the two groups. Cox regression analysis revealed that smoking (RR=3.189, 95% CI 1.020-9.968, P=0.046), diabetes (RR=2.717, 95% CI 1.113-6.631, P=0.028), and baseline National Institute of Health stroke scale (RR=2.984, 95% CI 1.049-8.485, P=0.040) were independent risk factors for major cerebrovascular events following CAS. CONCLUSION: CAS was superior to drug therapy in achieving better functional outcomes in patients with chronic internal carotid artery occlusion. However, CAS was not associated with a statistically significant reduction in cerebrovascular events or mortality. Larger and randomized clinical trials are required to ascertain the long-term benefits of CAS in patients with chronic internal carotid artery occlusion.

Impact of carotid artery stenting on plasma interleukin-6, tumor necrosis factor-α and C-reactive protein.

AIM: This study aimed to investigate the impact of carotid artery stenting (CAS) on plasma levels of interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-α) and C-reactive protein (CRP). METHODS: The levels of CRP, IL-6, and TNF-α were measured in 61 patients before CAS, 1 h, 2 weeks, 1 month, 6 months, and 12 months after the stenting. RESULTS: The levels of CRP, IL-6 and TNF-α increased immediately after CAS (P<0.05 or <0.01). The levels of CRP, IL-6 and TNF-α in patients receiving two stents for multiple lesions or single diffusive lesions was also high than in patients receiving one stent for a single lesion (P<0.05 or <0.01). The levels of CRP, IL-6 and TNF-α in patients with restenosis (14/61, or 23%) were higher than in those without restenosis (P<0.05 or <0.01). CONCLUSION: CAS was associated with a significant increase in plasma CRP, IL-6 and TNF-α. The levels of these inflammatory factors in patients with post-CAS restenosis were higher than in those without restenosis.

Host susceptibility to tuberculosis: insights from a longitudinal study of gene expression in diabetes.

Tuberculosis (TB) remains a major global disease, and diabetes, which is documented to increase susceptibility to TB threefold, is also becoming pandemic. This susceptibility has been attracting extensive research interest. The increased risk of TB in diabetes may serve as a unique model to understand host susceptibility to specific pathogens in humans. To examine this rationale, we investigated the expression of reported TB candidate genes in a longitudinal diabetes study. Two genes, HK2 and CD28, emerged as potential culprits in diabetes-increased TB susceptibility.

Expression of P-selectin, von Willebrand and endothelin-1 after carotid artery stenting.

BACKGROUND: This study was designed to investigate the impact of carotid artery stenting (CAS) on plasma levels of P-selectin, von Willebrand (vWF) and endothelin-1. PATIENTS AND METHODS: Sixty-seven patients who received CAS were divided into group 1 (one stent for a simple lesion, n = 38) and group 2 (two stents for complex lesions, n = 29). The levels of P-selectin, vWF and endothelin-1 were measured before CAS, 1 h, 6h, 24 h and 2 weeks after the stenting. RESULTS: Sixty-one patients completed one-year follow up. Restenosis was noted in 14 (23 %) patients, among these three (4.8 %) had a restenosis of > 50 % of the vascular lumen. In all patients, the levels of P-selectin, vWF and endothelin-1 increased immediately after CAS (P < 0.05 or < 0.01). The levels of vWF and endothelin-1 in group 2 were higher than in group 1 (P < 0.05 or 0.01). There was no significant difference in P-selectin and endothelin-1 between the restenosis and non-restenosis group (P > 0.05). The 24 h vWF in patients with restenosis were higher than in non-restenosis group (P < 0.05). CONCLUSIONS: CAS results in a significant increase in plasma P-selectin, vWF and endothelin-1. The post-CAS levels of P-selectin, vWF and endothelin-1 are related to the extent of endothelial injury. Whether they are associated with restenosis 12 months after the treatment requires further investigation.

Remapping the type I diabetes association of the CTLA4 locus.

The Type I Diabetes Genetics Consortium genotyped 24 single-nucleotide polymorphisms (SNPs) in the CTLA4 locus in 2298 type I diabetes (T1D) nuclear families (11 159 individuals, 5003 affected) to evaluate the recognized T1D association. The 24 CTLA4 SNPs span approximately 43 kb from the 5' flanking to 3' flanking region of the gene in the middle of an extended region of linkage disequilibrium of more than 100 kb. The genotyping was performed using two technologies (Illumina GoldenGate and Sequenom iPlex) on the same samples. The genotype calls by both the methods were highly consistent (the majority >99%). Previously reported T1D association from both the +49G>A and the CT60 SNPs was replicated. The reported association of the -319C>T SNP was not replicated. Although associated with T1D risk, it is likely that neither SNP is causative, as the peak of T1D association was from the SNP rs231727 at 3' flanking of the CTLA4 gene. Comprehensive resequencing and fine mapping of the CTLA4 region are still needed to clarify the causal variants.

The type I diabetes association of the IL2RA locus.

To confirm and fine map previous reports of association, the Type I Diabetes (T1D) Genetics Consortium (T1DGC) assembled a large collection of DNA samples from affected sib-pair (ASP) families with T1D (5003 affected individuals) and genotyped polymorphic markers. One of these loci, involving the IL2RA gene, had been reported to be due to three independent effects. The T1DGC genotyped 69 single-nucleotide polymorphisms (SNPs) that span approximately 88 kb from the 5' flanking to 3' flanking region of the IL2RA locus. The most highly associated SNP reported earlier (ss52580101) was not included in the genotyping list; however, a 5-SNP (rs3134883, rs3118470, rs7072793, rs4749955 and rs12251307) haplotype (H5) was identified that strongly tagged its minor allele with r(2)=0.869 (95% CI, 0.850-0.885). This haplotype was significantly protective (P=3.2 x 10(-5)) in the T1D ASP families, with an odds ratio virtually identical to that reported for ss52580101. The SNP marking the second independent locus, (rs11594656) showed no association in the T1DGC set and the third (rs2104286) could not be distinguished, by conditional regression, from H5. Instead, the most significant independent effect was detected from the 5' flanking IL2RA SNP rs4749955, which remained significant after regression for H5. Thus, we confirm independent effects at the IL2RA locus.

Reassessment of the type I diabetes association of the OAS1 locus.

To reassess the type I diabetes (T1D) association of the OAS1 locus, the Type I Diabetes Genetics Consortium (T1DGC) genotyped 11 tag single-nucleotide polymorphisms spanning approximately 41 kb from the 5' to 3' flanking region. For each sample obtained from over 2000 affected sib-pair families from nine cohorts, the genotyping was performed on both the Illumina Golden Gate and Sequenom iPlex platforms. The data suggest that there may be a weak association with T1D for two OAS1 polymorphisms, rs3741981 and rs10774671, in populations of European descent. The OAS1 locus is close to a recently identified T1D-associated linkage disequilibrium (LD) block in human chromosome 12q24. Extended LD in populations earlier examined may account for the prior observation of an association of T1D with OAS1 variants. This possibility needs to be addressed further by fine mapping of the T1D association represented in 12q24.

Association of RASGRP1 with type 1 diabetes is revealed by combined follow-up of two genome-wide studies.

BACKGROUND: The two genome-wide association studies published by us and by the Wellcome Trust Case-Control Consortium (WTCCC) revealed a number of novel loci, but neither had the statistical power to elucidate all of the genetic components of type 1 diabetes risk, a task for which larger effective sample sizes are needed. METHODS: We analysed data from two sources: (1) The previously published second stage of our study, with a total sample size of the two stages consisting of 1046 Canadian case-parent trios and 538 multiplex families with 929 affected offspring from the Type 1 Diabetes Genetics Consortium (T1DGC); (2) the Rapid Response 2 (RR2) project of the T1DGC, which genotyped 4417 individuals from 1062 non-overlapping families, including 2059 affected individuals (mostly sibling pairs) for the 1536 markers with the highest statistical significance for type 1 diabetes in the WTCCC results. RESULTS: One locus, mapping to a linkage disequilibrium (LD) block at chr15q14, reached statistical significance by combining results from two markers (rs17574546 and rs7171171) in perfect LD with each other (r2 = 1). We obtained a joint p value of 1.3 x 10(-6), which exceeds by an order of magnitude the conservative threshold of 3.26 x 10(-5) obtained by correcting for the 1536 single nucleotide polymorphisms (SNPs) tested in our study. Meta-analysis with the original WTCCC genome-wide data produced a p value of 5.83 x 10(-9). CONCLUSIONS: A novel type 1 diabetes locus was discovered. It involves RASGRP1, a gene known to play a crucial role in thymocyte differentiation and T cell receptor (TCR) signalling by activating the Ras signalling pathway.

The effect of the MHC locus on autoantibodies in type 1 diabetes.

OBJECTIVE: To investigate whether the presence of autoantibodies specific for type 1 diabetes (T1D) is determined by the major genetic susceptibility locus for the disease at the HLA genes, using the T1D Genetics Consortium data. METHODS: We analysed anti-IA-2 and anti-GAD 65 autoantibody data from 2282 T1D patients from 1117 multiplex families. HLA genotyping was available for all cases and their parents and association with autoantibody positivity was tested by the transmission disequilibrium test. RESULTS: Association of anti-IA-2 with the HLA genes was detected at high statistical significance. HLA-DRB1*0401 confers both the strongest type 1 diabetes risk, and positive association of anti-IA-2, whereas the DRB1*03- DQA1*0501-DQB1*0201 haplotype, associated less strongly with T1D, showed a significant negative association with anti-IA-2 positivity. Interestingly, HLA-A*24 is also negatively associated with anti-IA-2, independently of the DRB1*03- DQA1*0501-DQB1*0201 haplotype. No statistically significant association was identified between anti-GAD65 and HLA. CONCLUSIONS: This study highlights that IA-2 as an autoantigen depends on HLA genotype and suggests new insights into the mechanism of loss of immune tolerance.

The association between type 1 diabetes and the ITPR3 gene polymorphism due to linkage disequilibrium with HLA class II.

A fine mapping study of the MHC region in a Swedish case-control population sample reported a novel type 1 diabetes (T1D) association from the inositol 1-, 4-, 5-trisphosphate receptor type 3 gene (ITPR3) in a case-control study, reportedly independent of the HLA class II effect. We attempted to replicate this novel association in a family-based study of 1120 T1D families with at least one affected child, an approach immune to population stratification. We found association of the ITPR3 single nucleotide polymorphisms (SNPs) rs2296336 with T1D but in a direction opposite to that reported. Moreover, rs2296336 was in linkage disequilibrium (LD) with specific alleles of the HLA DQB1 gene. Conditional regression showed that all of the ITPR3 SNP T1D association could be accounted for by the DQB1 effect. Therefore, our findings do not support an obvious role of genetic variation of the ITPR3 gene in T1D risk.

The association between the IFIH1 locus and type 1 diabetes.

AIMS/HYPOTHESIS: We set out to validate a recently reported type 1 diabetes association from the IFIH1 gene variation in an independent cohort from a population of mixed European descent. METHODS: We genotyped five single-nucleotide polymorphisms in the IFIH1 locus, i.e. rs2111485, rs1990760, rs3747517, rs17783344 and rs984971589, in 589 type 1 diabetes nuclear family trios (1,767 individuals). RESULTS: This study independently replicated the reported genetic association using a family-based approach. CONCLUSIONS/INTERPRETATION: The reported type 1 diabetes association is from a linkage disequilibrium region including three candidate genes, i.e. FAP, IFIH1 and GCA. Further variant discovery and fine mapping could help clarify a novel type 1 diabetes mechanism.

Lack of association of type 1 diabetes with the IL4R gene.

AIMS/HYPOTHESIS: The association between IL4R and type 1 diabetes has been tested in many studies in recent years, with contradictory results. The aim of this study was to re-evaluate the genetic association in type 1 diabetic nuclear families of mixed European background. SUBJECTS, MATERIALS AND METHODS: We genotyped six non-synonymous single-nucleotide polymorphisms (SNPs) of the IL4R gene in 830 nuclear families as specified above, including a French Canadian subset. RESULTS: No association between type 1 diabetes and any SNP or haplotype was found by the transmission disequilibrium test. CONCLUSIONS/INTERPRETATION: Previous positive reports may be due to population stratification as, according to HapMap data, allele frequencies in the IL4R region vary considerably by ethnicity.

Type 1 diabetes and the OAS gene cluster: association with splicing polymorphism or haplotype?

BACKGROUND: The 2',5'-oligoadenylate synthetase genes (OAS1, OAS2, and OAS3) map to human chromosome 12q24 and encode a family of enzymes pivotal to innate antiviral defence. Recently, the minor allele of an OAS1 single nucleotide polymorphism (SNP) that alters splicing (rs10774671) was found to be associated with increased enzymatic activity and, in a case-sibling control study, with type 1 diabetes (T1D). METHODS: We have confirmed this T1D association in 784 nuclear families (two parents and at least one affected offspring) by the transmission disequilibrium test (TDT; G:A = 386:329, p = 0.033). However, because of linkage disequilibrium within OAS1 and with the other two OAS genes, functional attribution of the association to this SNP cannot be assumed. To help answer this question, we also genotyped two non-synonymous SNPs in OAS1 exons 3 and 7. RESULTS: All three SNPs showed significant transmission distortion. Three of the eight possible haplotypes accounted for 98.4% of parental chromosomes and two of them carried the non-predisposing A allele at rs10774671. Parents heterozygous for these two haplotypes showed significant transmission distortion (p = 0.009) despite being homozygous at rs10774671. CONCLUSIONS: We confirm the T1D association with rs10774671, but we conclude that it cannot be attributed (solely) to the splicing variant rs10774671. A serine/glycine substitution in OAS1 exon 3 is more likely a functional variant.