Assessment of iris volume in glaucoma patients with type 2 diabetes mellitus by AS-OCT.

AIM: To examine the change of iris volume measured by CASIA2 anterior segment optical coherence tomography (AS-OCT) in glaucoma patients with or without type 2 diabetes mellitus (T2DM) and explore if there is a correlation between hemoglobin A1c (HbA1c) level and iris volume. METHODS: In a cross-sectional study, 72 patients (115 eyes) were divided into two groups: primary open angle glaucoma (POAG) group (55 eyes) and primary angle-closure glaucoma (PACG) group (60 eyes). Patients in each group were separately classified into patients with or without T2DM. Iris volume and glycosylated HbA1c level were measured and analyzed. RESULTS: In the PACG group, diabetic patients' iris volume was significantly lower than those of non-diabetics (P=0.02), and there was a significant correlation between iris volume and HbA1c level in the PACG group (r=-0.26, P=0.04). However, diabetic POAG patients' iris volume was noticeably higher than those of non-diabetics (P=0.01), and there was a significant correlation between HbA1c level and iris volume (r=0.32, P=0.02). CONCLUSION: Diabetes mellitus impact iris volume size, as seen by increased iris volume in the POAG group and decreased iris volume in the PACG group. In addition, iris volume is significantly correlated with HbA1c level in glaucoma patients. These findings imply that T2DM may compromise iris ultrastructure in glaucoma patients.

Association of macular corneal dystrophy with excessive cell senescence and apoptosis induced by the novel mutant CHST6.

Macular corneal dystrophy (MCD) is a rare form of hereditary corneal dystrophy caused by CHST6 mutations. Owing to the genetic heterogeneity and population differences among patients with MCD, the genetic cause of MCD has not been fully elucidated, and the pathogenesis underlying the genetic mutation is still unclear. In this study, Chinese families and sporadic patients were included as subjects, and clinical and genetic analyses were performed to detect novel CHST6 mutations. In addition, the underlying pathogenic mechanisms of MCD were investigated by in vitro cell experiments. Two consanguineously married families and 10 sporadic patients with MCD were enrolled. Direct sequencing of the CHST6 gene was performed in all the patients to identify novel mutations. Wild-type and mutant overexpression cell lines were constructed to study the effects of the mutation in vitro. The expressions of endoplasmic reticulum (ER) stress markers and apoptotic factors, cell senescence, and migration levels tests were performed in different overexpression cell lines. As a result, four novel mutations (R155Afs*66, S84Cfs*17, E71G, and E71Q) and 10 previously reported mutations in the CHST6 gene were identified. Among the reported mutations, the most frequent mutations detected in the patients were L21Rfs*88 (4/14) and L21H (4/14). All the novel mutations were absent in the 50 healthy controls and were predicted to alter highly conserved amino acids across the different species and considered to be "disease causing" by function prediction. The results of the in vitro cell experiment further demonstrated that the novel homozygous frameshift mutations (S84Cfs*17 and R155Afs*66) of CHST6 detected in the consanguineously married families could lead to truncated proteins with defect functions, higher ER stress and apoptotic levels, decreased cell migration, and excessive cell senescence in corneal stromal cells, thereby affecting the normal functions of corneal stromal cells. These changes might play important roles in corneal opacity, which is characteristic of corneas with MCD. Our study extended the existing spectrum of disease-causing mutations and further elucidated the underlying pathogenic mechanisms of MCD.

Associations of lens thickness and axial length with outcomes of laser peripheral iridotomy.

AIM: To investigate the association of axial length (AL), lens thickness (LT), and lens vault (LV) with postoperative anterior chamber angle metrics after laser peripheral iridotomy (LPI). METHODS: Prospective observational study of 69 patients (97 eyes) were diagnosed as primary angle-closure suspect (PACS), primary angle closure (PAC) or primary angle-closure glaucoma (PACG). AL, LT, anterior central chamber depth (ACD), angle opening distance (AOD), trabecular iris angle (TIA), and angle recess area (ARA) were measured before and 1wk after LPI. The association between AL, LT, LV with ACD, AOD, TIA, ARA were analyzed by comparing the differences between preoperative and postoperative measurements for anterior segment biometric parameters. RESULTS: ACD, AOD, TIA, and ARA were significantly increased after LPI (all P<0.05). Greater LT was significantly associated with greater postoperative increases in ACD, AOD, TIA, and ARA (all P<0.05). AL was not significantly associated with changes of anterior segment biometric parameters. Greater LV was significantly associated with greater postoperative increases in ACD, AOD, and TIA (all P<0.05), but was not significantly associated with changes of ARA. CONCLUSION: Greater baseline LT and LV measurements are associated with greater increases in anterior segment biometric parameters after laser peripheral iridotomy. AL are not associated with the change of anterior segment biometric parameters.

Ocular bacterial infections at a tertiary eye center in China: a 5-year review of pathogen distribution and antibiotic sensitivity.

AIM: To provide statistical evidence for the use of antibiotics in ophthalmology by assessing the distribution and antibiotic sensitivity of bacterial isolates from ocular specimens with suspected microbial infections. METHODS: This study applied a retrospective analysis of 3690 bacterial isolates from ocular specimens, which were obtained from the conjunctiva, cornea, aqueous humor, vitreous body, and other ocular sites of the patients at Shandong Eye Institute in northern China from January 2013 to December 2017. The parameters assessed mainly included the distribution of isolated bacteria and the results of susceptibility tests for antibiotics. In the analysis of antibiotic sensitivities, the bacteria were divided into four groups according to gram staining, and statistical methods were used to compare their antibiotic sensitivities. RESULTS: Among the 3690 isolated bacterial strains, Staphylococcus epidermidis (2007, 54.39%) accounted for the highest proportion. As for the total isolates, their sensitivity rate to gatifloxacin was up to 90.01%, with four types of gram-stained bacteria being all highly sensitive to it, but their sensitivity rate to levofloxacin was only 51.91%. The sensitivity rate of gram-negative bacilli (G-B) to levofloxacin was 83.66%, significantly higher than the other three types of gram-stained bacteria (P<0.05). Gram-positive cocci (G+C, 97.95%) and gram-positive bacilli (G+B, 97.54%) were more sensitive to vancomycin than gram-negative cocci (G-C, 70.59%) and G-B (68.57%; P<0.05). For fusidic acid, the sensitivity rates of G+C (89.83%) and G+B (73.37%) were significantly higher than that of G-B (29.83%; P<0.05). The gram-negative bacteria's sensitivity rate to cefuroxime was as low as 59.25%, but only G-B was less sensitive to cefuroxime (57.28%), while G-C was still highly sensitive (89.29%). The sensitivity rate of gram-positive bacteria to moxifloxacin was as high as 80.28%, but only G+C was highly sensitive to moxifloxacin (81.21%), while G+B was still less sensitive (32.00%). CONCLUSION: Staphylococcus epidermidis is the predominant isolate in all ocular specimens with bacteria. Gatifloxacin is more suitable for topical prophylactic use than levofloxacin in ophthalmology when necessary. Vancomycin and fusidic acid both have better effects on gram-positive bacteria than gram-negative bacteria. More accurate antibiotic sensitivity analysis results can be obtained when a more detailed bacterial classification and more appropriate statistical methods are performed.

Mutation analysis of FBN1 gene in two Chinese families with congenital ectopia lentis in northern China.

AIM: To summarize the phenotypes and identify the underlying genetic cause of the fibrillin-1 (FBN1) gene responsible for congenital ectopia lentis (EL) in two Chinese families in northern China. METHODS: A detailed family history and clinical data from all participants were collected by clinical examination. The candidate genes were captured and sequenced by targeted next-generation sequencing, and the results were confirmed by Sanger sequencing. Haplotyping was used to confirm the mutation sequence. Real-time PCR was used to determine the FBN1 messenger ribonucleic acid (mRNA) levels in patients with EL and in unaffected family members. RESULTS: The probands and other patients in the two families were affected with congenital isolated EL. A heterozygous FBN1 mutation in exon 21 (c.2420_IVS20-8 delTCTGAAACAinsCGAAAG) was identified in FAMILY-1. A heterozygous FBN1 mutation in exon 14 (c.1633C>T, p.R545C) was identified in FAMILY-2. Each mutation co-segregated with the affected individuals in the family and did not exist in unaffected family members and 200 unrelated normal controls. CONCLUSION: The insertion-deletion mutation (c.2420 IVS20-8delTCTGAAACA insCGAAAG) in the FBN1 gene is first identified in isolated EL. The mutation (c.1633C>T) in the FBN1 gene was a known mutation in EL patient. The variable phenotypes among the patients expand the phenotypic spectrum of EL in a different ethnic background.

Novel mutations in CRYBB1/CRYBB2 identified by targeted exome sequencing in Chinese families with congenital cataract.

AIM: To summarize the phenotypes and identify the underlying genetic cause of the CRYBB1 and CRYBB2 gene responsible for congenital cataract in two Chinese families. METHODS: Detailed family histories and clinical data were collected from patients during an ophthalmologic examination. Of 523 inheritable genetic vision system-related genes were captured and sequenced by targeted next-generation sequencing, and the results were confirmed by Sanger sequencing. The possible functional impacts of an amino acid substitution were performed with PolyPhen-2 and SIFT predictions. RESULTS: The patients in the two families were affected with congenital cataract. Sixty-five (FAMILY-1) and sixty-two (FAMILY-2) single-nucleotide polymorphisms and indels were selected by recommended filtering criteria. Segregation was then analyzed by applying Sanger sequencing with the family members. A heterozygous CRYBB1 mutation in exon 4 (c.347T>C, p.L116P) was identified in sixteen patients in FAMILY-1. A heterozygous CRYBB2 mutation in exon 5 (c.355G>A, p.G119R) was identified in three patients in FAMILY-2. Each mutation co-segregated with the affected individuals and did not exist in unaffected family members and 200 unrelated normal controls. The mutation was predicted to be highly conservative and to be deleterious by both PolyPhen-2 and SIFT. CONCLUSION: The CRYBB1 mutation (c.347T>C) and CRYBB2 mutation (c.355G>A) are novel in patients with congenital cataract. We summarize the variable phenotypes among the patients, which expanded the phenotypic spectrum of congenital cataract in a different ethnic background.

A Chinese family with Axenfeld-Rieger syndrome: report of the clinical and genetic findings.

AIM: To describe a Chinese family affected by a severe form of Axenfeld-Rieger syndrome (ARS) and characterize the molecular defect in PITX2 in the family. METHODS: Patients presented with typical ARS from a Chinese family were investigated. We performed genome-wide linkage scan and exome sequencing to identify the pathogenic mutations. Candidate mutations were verified for co-segregation in the whole pedigree using Sanger sequencing. Real-time polymerase chain reaction (RT-PCR) and Western blotting were performed to verify the expression of the pathogenic gene. RESULTS: Genome-wide linkage and exome sequencing analyses showed PITX2 as the disease candidate gene. A>G substitution at position -11 of 3'ss of exon 5 (IVS5-11A>G) that co-segregated with the disease phenotype was discovered in the family. The PITX2 messenger ribonucleic acid and protein levels were about 50% lower in patients with ARS than in unaffected family members in the family. CONCLUSION: Our findings implicate the first intronic mutation of the PITX2 gene in the pathogenesis of a severe form of ARS in a Chinese family. This study highlights the importance of a systematic search for intronic mutation in ARS cases for which no mutations in the exons of PITX2 have been found.

Corneal infection in Shandong peninsula of China: a 10-year retrospective study on 578 cases.

AIM: To determine the epidemiological characteristics, clinical signs, laboratory findings, and outcomes in patients with corneal infection in Shandong peninsula of China. METHODS: The medical records of 578 inpatients (578 eyes) with corneal infection were reviewed retrospectively for demographic characteristics, risk factors, seasonal variation, clinical signs, laboratory findings, and treatment strategy. Patient history, ocular examination findings using slit-lamp biomicroscopy, laboratory findings resulted from microbiological cultures, and treatment. RESULTS: Fungal keratitis constituted 58.48% of cases of infectious keratitis among the inpatients, followed by herpes simplex keratitis (20.76%), bacterial keratitis (19.03%) and acanthamoeba keratitis (1.73%). The most common risk factor was corneal trauma (71.80%). The direct microscopic examination (338 cases) using potassium hydroxide (KOH) wet mounts was positive in 296 cases (87.57%). Among the 298 fungal culture-positive cases, Fusarium species were the most common isolates (70.47%). A total of 517 cases (89.45%) received surgical intervention, including 255 (44.12%) cases of penetrating keratoplasty, 74 (12.80%) cases of lamellar keratoplasty which has become increasingly popular, and 77 cases (13.32%) of evisceration or enucleation. CONCLUSION: At present, infectious keratitis is a primary corneal disease causing blindness in China. With Fusarium species being the most commonly identified pathogens, fungal keratitis is the leading cause of severe infectious corneal ulcers in Shandong peninsula of China.

A novel method to derive and expand mice neural stem cells efficiently without neuro-sphere formation.

Neural stem cells (NSCs) are multi-potent stem cells able to self-renew and generate immature and differentiated cell populations by asymmetric division. The NSCs are of considerable interest for cell replacement in neuro-degenerative diseases. NSCs are usually identified and expanded by their ability to generate free-floating aggregates termed neurospheres. However, neurospheres are not a pure population of NSCs with as little as 1% population in primary spheres. Neurospheres also contain neurons, astrocytes and oligodendrocytes. The heterogeneity of these cells may hinder their repopulation potential when used in cell transplantation. Furthermore, to obtain 1 million NSCs by the neurosphere protocol usually takes one month, which is inconvenient for future clinical trials. In this study, we tried to derive the NSCs from mice embryo neuroepithelium without neurosphere formation. Three different protocols were compared. We generated a direct and efficient NSCs generation, expanding and freezing protocol. This protocol can provide sufficient amount of the NSCs from first a few passages for cell transplantation.

[Study on the effect of grape seed proanthocyanidins on increasing the radiosensitivity for X-ray].

OBJECTIVE: To investigate the effect of Grape Seed Proanthocyanidins (GSPs) on enhancing the radiosensitivity of human hepatic carcinoma cell line HepG2, human cervical cancer cell line Hela and human leukemia cell line K562 for X-ray in vitro. METHODS: The killing effect of GSPs combined with X-ray on cells was evaluated by SRB and clone formation assay. RESULTS: The GSPs had obvious cytotoxicity on three cell lines in a dose-dependent and time-dependent manners. However, inhibition rate of different cell line were quite different, the strongest one was human leukemia K562 cells and the others were weak. The sensitization ranges calculated by univariate analysis were 6.25-12.5 microg/mL for human leukemia K562 cells. Sensitization enhancement ratio was 1.94 using curve fitting method for K562 cells. CONCLUSION: GSPs can obviously enhance the radiosensitivity of cancer cells in vitro. The mechanism of sensitization effect may be related to the effects of GSPs on oxygen balance and cell cycle.

Monocytic differentiation of K562 cells induced by proanthocyanidins from grape seeds.

Grape seeds procyanidins can inhibit the proliferation of some cancer cell lines and have strong antioxidant activity. The purpose of this study was to investigate whether grape seeds procyanidins affect the proliferation and redifferentiation in K562 cells. The sulforhodamine B colorimetric assay and trypan blue staining were used to measure cell proliferation and survival. Morphological changes, NBT reductive activity, and surface antigens were used to detect redifferentiation of K562 cells. Intracellular reactive oxygen species (iROS) were detected by a fluorescent probe. Grape seeds procyanidins inhibited cell proliferation but the treatment did not appreciably increase lethality. After treatment with grape seeds procyanidins, a typical differentiated morphology was observed. The positive rate of CD11b and CD14 cells and NBT reductive activities increased significantly. As antioxidants, grape seeds procyanidins can induce arrest in the phase G1 and decrease iROS formation. All results indicate that the antioxidant grape seeds procyanidins are likely to induce monocytic differentiation in leukemia cells, mostly through decreasing iROS formation and inducing phase G1 arrest.

[Expression of integrin during the course of adhesion between fungi and corneal epithelial cells].

OBJECTIVE: To investigate the expression of integrin during the course of adhesion between fungi and corneal epithelial cells. METHODS: It was an experimental study. Human corneal epithelial cells were cultured and the adhesion model were established between human corneal epithelial cells and Fusarium solani (CGMCC 3.1829) or Aspergillus fumigatus (CGMCC 3.0772) in vitro. Human corneal epithelial cells were incubated with Fusarium solani or Aspergillus fumigatus at 37°C and the non-adhered fungi were washed out with sterile phosphate buffered solution (PBS). The total RNA was extract from the human corneal epithelial cells. Real-time polymerase chain reaction (RT-PCR) for the expression of integrin was performed. RESULTS: The results of RT-PCR showed that during the course of adhesion between Aspergillus fumigatus and corneal epithelial cells, the expression of integrin alpha L (ITGAL), integrin alpha M (ITGAM), integrin alpha X (ITGAX) and integrin beta 2 (ITGB2) were upregulated significantly. However, during the course of adhesion between Fusarium solani and corneal epithelial cells, there was no significant differences in the expression of those 14 kinds of integrin. CONCLUSIONS: Integrin αLß2, αMß2 and αXß2 are all belong to the leukocyte adhesion receptor group (ß2 group) in integrin family. These three members are all involved in the adhesion of Aspergillus fumigatus and corneal epithelial cells. With the adhesion, the expression of integrin is upregulated. These results suggest that the integrin-mediated adhesion is different with different kinds of fungi. Integrin plays an important role in adhesion of fungi with human corneal epithelial cells.

Clinical effects of three types of silicone intubations in repairing lacerations of canaliculus.

OBJECTIVE: To evaluate the clinical effects of one-passage, double-passage and circular canalicular intubations in repairing lacerations of canaliculus. METHODS: A total of 109 eyes in 109 cases of canalicular laceration were repaired with three types of silicone intubations, among which 23 with one-passage canalicular intubation, 51 with double-passage canalicular intubation, and 35 with circular canalicular intubation. The average follow-up period was 12-15 months. RESULTS: The wound/junction of the lacrimal canaliculi was ruptured in 5 cases (9.80%) of the double-passage group, 3 cases (8.57%) of the circular group, and 8 cases (34.78%) of the one-passage group. The rupture incidence of the one-passage group was significantly higher than that of the other two groups (X(2) equal to 9.416, P less than 0.01). During the intubation, canaliculitis was observed in 12 cases (23.53%) of the double-passage group, while only 3 cases (8.57%) in the circular group and 8 cases (34.78%) in the one-passage group. The circular group had significantly lower incidence of canaliculitis than the other two groups (X(2) equal to 6.095, P less than 0.05). After extubation 6 months after laceration repair, the lacrimal passage remained patent with canalicular irrigation in 46 cases (90.20%) in the double-passage group, 30 cases (85.71%) in the circular group and 15 cases (65.22%) in the one-passage group. Six months after surgery, the canalicular patency in the one-passage group was significantly lower than that of the other two groups (X(2) equal to 7.390, P less than 0.05). CONCLUSIONS: Circular canalicular intubation is more stable and has less surgical complications than the double-passage and one-passage canalicular intubations. It is also more effective clinically 12-15 months after laceration surgery.

Development of a prediction rule to estimate the probability of acceptable intraocular pressure reduction after selective laser trabeculoplasty in open-angle glaucoma and ocular hypertension.

PURPOSE: To develop and validate a prediction rule to estimate the probability of acceptable intraocular pressure (IOP) reduction after selective laser trabeculoplasty (SLT) in ocular hypertension and open-angle glaucoma. PATIENTS AND METHODS: The study population was derived from a cohort of 220 patients with ocular hypertension, open-angle glaucoma, or normal tension glaucoma. A > or =20% reduction in IOP (mm Hg) from the baseline IOP at 6 months after SLT was considered treatment success. Logistic multivariate regression modeling was performed to develop a prediction rule. RESULTS: In multivariate logistic regression analyses, pre-SLT IOP and maximum IOP were identified as independent predictors for > or =20% IOP reduction at 6 months with adjusted odds ratios of 1.3 and 0.9, respectively, controlling for sex, diagnosis, pigment of anterior chamber, and washout of eye drops. The area under receiver operator characteristic curve was 0.716. Calibration of this prediction rule showed good agreement between predicted and observed probabilities of acceptable IOP reduction. If a probability of acceptable IOP reduction of 50% or greater is used as the minimal clinical threshold for treatment, the prediction rule had a sensitivity and specificity of 91.3% and 30.4%, respectively. CONCLUSIONS: SLT efficacy is positively associated with IOP elevation before SLT treatment and adversely associated with the maximum IOP ever recorded in history. Pigmentation of the anterior chamber angle, diagnosis, washout of eye drops, and sex are not associated with SLT treatment efficacy. This prediction rule should be further validated with a comparable prospective clinical study cohort.