The effect of different pterygium surgery techniques on the ocular surface parameters in different durations: a systematic review and meta-analysis.

PURPOSE: To evaluate the effects of different pterygium surgery techniques on ocular surface (OS) in different follow-up periods. METHODS: PubMed, Cochrane Library, Web of Science, China National Knowledge Infrastructure, Wan Fang, and China Biology Medicine disc were searched for studies reporting pre- and post-operative OS parameters in pterygium. RESULTS: A total of 33 articles were finally included. Three OS parameters showed relatively consistent changing trends after surgery including ocular surface disease index (OSDI), tear film break-up time (BUT), and score of corneal fluorescein staining (SCFS). They worsened significantly at 1w post-operation and then gradually improved: OSDI and BUT showed obvious improvement in 1 m post-operation (SMD = - 0.58, 95%CI = [- 1.04, - 0.13]; SMD = 0.42, 95%CI = [0.06, 0.78]); SCFS was restored to preoperative levels in 3 m after surgery (SMD = - 0.54, 95%CI = [- 1.16, 0.07]). Another parameter, Schirmer test without anesthesia (SIT), presented transient increase at 1w post-operation (SMD = 0.87, 95%CI = [0.27, 1.47]) and presented a relatively stable improvement after 1 m post-operation (SMD = 0.52, 95%CI = [0.16, 0.89]). All parameters in amniotic membrane graft (AMT) showed better improvement in early stage and they showed non-inferior improvements in the long term compared with conjunctival autograft (CAG). Limbal-conjunctival autograft (LCAG) made excellent improvement to OS in the long term while pterygium excision (PE) showed the worst OS. The type of pterygium (primary and secondary), diabetes mellitus (DM) status, and fixation method had certain effects on the results. CONCLUSIONS: OS of pterygium is deteriorated at 1w post-operation then gradually improved to preoperative levels after 1 m post-operation. Among various surgery techniques, LCAG had the best improvement to OS which especially displayed in the long-term outcomes.

The unique properties of tear film breakup process in patients with nasal unilateral pterygium.

SIGNIFICANCE: This study found that the unique properties of tear film breakup process in eyes with pterygium, combined with ocular surface parameters, further revealed specific dynamic mechanism. It suggested that the thickness of pterygium was especially valuable in deciding the necessity of surgical management. PURPOSE: This study aimed to explore the dynamic mechanism of tear film instability in eyes with pterygium. METHODS: A paired-eye controlled cross-sectional study was conducted. Seventy-eight patients with nasal pterygium were enrolled. Fluorescein tear film breakup was observed. Several key parameters related to tear film quality were defined and analyzed, including total breakup area (mathematically derived from pixel size using MATLAB), breakup velocity, fluorescein breakup time, breakup location and pattern, tear meniscus height, score of fluorescein corneal staining, and meiboscore. RESULTS: With comparable tear meniscus height, score of fluorescein corneal staining, and meiboscore between paired eyes (p > 0.05), eyes with pterygium had shorter breakup time, larger breakup area, and faster breakup velocity (p < 0.05). In eyes with pterygium, a positive correlation between meiboscore and pterygium parameters including length, thickness, and size was observed (p > 0.001). As the thickness increased, difference of breakup time and area between paired eyes increased (p = 0.02 and 0.046). Eyes with pterygium had more fixed inferonasal breakup location and often presented as dimple break (60%), whereas random break was the most common in contralateral normal eyes (62%). A unique breakup pattern named pterygium-induced local dimple break was found. It displayed as an irregular but vertical line-like shape appearing after lipid layer spreading, which was adjacent to the lower margin of pterygium and presented with unique properties including inferonasal breakup location, local breakup area, shorten breakup time, and faster breakup velocity. CONCLUSIONS: Eyes with pterygium showed a unique tear film breakup process and novel breakup pattern named pterygium-induced local dimple break . Dynamic mechanism played a significant role in tear film instability of eyes with pterygium rather than aqueous deficiency and increased evaporation.

Clinical observation of tear film breakup time with a novel smartphone-attachable technology.

PURPOSE: To demonstrate the practicability of a portable instrument in assessing tear film breakup time (TFBUT): a lens attachment for smartphones (LAS). METHODS: By applying LAS in combination with the iPhone 12 pro, and a recordable slit-lamp microscope, we obtained TFBUT videos from 58 volunteers. The comparison between the conventional slit-lamp microscope and LAS by an experienced ophthalmologist. Moreover, we also invited an ophthalmic postgraduate student and an undergraduate student with no clinical experience to assess TFBUT in those videos. The inter-observer reliability was assessed using intraclass correlation coefficients (ICC). RESULTS: The TFBUT of 116 eyes in total was recorded. Reliability indexes were adequate. The Spearman's correlation analysis and the intraclass correlation coefficient suggested a strong correlation between the 2 modalities (Right eye: Spearman's r = 0.929, 95% confidence interval (CI) = 0.847-0.963, ICC = 0.978, p < 0.001; Left eye: Spearman's r = 0.931, 95% CI = 0.866-0.964, ICC = 0.985, p < 0.001;). Between instruments, the majority of TFBUT measurements showed good agreement on Bland Altman plot. A high concordance was observed in TFBUT, when assessed by an ophthalmologist and an ophthalmic postgraduate student (Left eye: LAS ICC = 0.951, p < 0.001; Left eye: slit-lamp microscope ICC = 0.944, p < 0.001). CONCLUSIONS: Compared with the conventional slit-lamp microscope, the LAS has sufficient validity for evaluating TFBUT in clinics or at home.

Macular pucker, an atypical clinical presentation of ocular toxoplasmosis: a case report.

BACKGROUND: Ocular toxoplasmosis caused by Toxoplasma gondii is an infectious disease which is widely distributed around the world and can present with various clinic manifestations. We are here reporting an unusual case presented with epiretinal membrane (ERM), i.e., macular pucker. CASE PRESENTATION: A 16-year old male patient visited our outpatient clinic complaining of decreased vision for about 8 years in his left eye. The best-corrected visual acuity (BCVA) was 20/20 OD and 20/400 OS. There was sensory exotropia in his left eye. No inflammatory cells or flare were found in his anterior chamber or vitreous cavity OU. An ERM involving his left macular area was found on his dilated fundus exam, which was confirmed by Optical Coherence Tomography (OCT). The ERM was found to involve his left macular area with his foveal ellipsoid zone absent. The right eye was found to be within normal limit. After a thorough discussion with the patient and his parents about treatment options and surgical benefits, risks and alternatives, we performed vitrectomy, peeled off the ERM and collected the vitreous sample for parasite testing during the procedure. Patient's blood also was drawn for serological testing. Vitreous sample analysis and serological tests confirmed ocular toxoplasmosis OS as his final diagnosis. Unfortunately, the BCVA of this patient was not improved after the surgery, but the exotropia disappeared. CONCLUSION: ERM is an unusual clinical presentation of ocular toxoplasmosis. We may add Toxoplasma gondii infection as a differential diagnosis when encountering ERM cases.

Mitochondrial DNA heteroplasmy rises in substantial nigra of aged PINK1 KO mice.

Mutations in PINK1 and Parkin result in early-onset autosomal recessive Parkinson's disease (PD). PINK1/Parkin pathway maintain mitochondrial function by mediating the clearance of damaged mitochondria. However, the role of PINK1/Parkin in maintaining the balance of mtDNA heteroplasmy is still unknown. Here, we isolated mitochondrial DNA (mtDNA) from cortex, striatum and substantia nigra of wildtype (WT), PINK1 knockout (PINK1 KO) and Parkin knockout (Parkin KO) mice to analyze mtDNA heteroplasmy induced by PINK1/Parkin deficiency or aging. Our results showed that the Single Nucleotide Variants (SNVs) of late-onset somatic variants mainly increased with aging. Conversely, the early-onset somatic variants exhibited significant increase in the cortex and substantia nigra of PINK1 KO mice than WT mice of the same age. Increased average variant allele frequency was observed in aged PINK1 KO mice and in substantial nigra of aged Parkin KO mice than in WT mice. Cumulative variant allele frequency in the substantia nigra of PINK1 KO mice was significantly higher than that in WT mice, further supporting the pivotal role of PINK1 in mtDNA maintenance. This study presented a new evidence for PINK1 and Parkin in participating in mitochondrial quality control and provided clues for further revealing the role of PINK1 and Parkin in the pathogenesis of PD.

Expression of PD-L1 in ovarian cancer and its synergistic antitumor effect with PARP inhibitor.

BACKGROUND: Ovarian cancer samples were studied to determine the expression of programmed death ligand-1 (PD-L1) and its relationship with prognosis, and to explore the effect and potential mechanism of a PARP inhibitor combined with PD-L1 monoclonal antibody for the treatment of ovarian cancer. MATERIALS AND METHODS: PD-L1 expression in paraffin-embedded tissues of ovarian cancer was detected by immunohistochemistry (IHC). Flow cytometry was used to detect PD-L1 expression in TILs. Furthermore, we investigated the mechanism of the upregulation of PD-L1 expression by PARP inhibitors in vitro and verified the combined effect in vivo. RESULTS: Our study demonstrated that PD-L1 expression in ovarian cancer tissues was associated with the FIGO stage (P = 0.026). OS was significantly lower in high PD-L1 expression group than in the low expression group (P = 0.0005, HR = 2.689), PD-L1 high expression (P = 0.023, HR = 2.275) and FIGO stage (P = 0.024, HR = 11.229) were independent risk factors affecting the survival and prognosis of ovarian cancer patients. Flow cytometry test suggested that PD-L1+ expression was negatively correlated with CD8+ T cell count in ovarian cancer cells (P = 0.054, r = -0.624). In vitro experiments revealed that PD-L1 expression of ovarian cancer cell lines was upregulated after intervention with PARP inhibitors through the Chk1 pathway. The results of in vivo experiments suggested that the growth volume and quality of tumors in the combination group were significantly lower than those in control group (P < 0.05). CONCLUSIONS: PARP inhibitors could induce upregulation of PD-L1 expression by promoting phosphorylation of chk1. Antagonistic PD-L1 could reverse the inhibitory effect of PARP inhibitors on CD8+T cells, and had synergistic antitumor effect with PARP inhibitors.

Comparison of two techniques for toric intraocular lens implantation: hydroimplantation versus ophthalmic viscosurgical devices.

BACKGROUND: To compare the results between hydroimplantation of a single-piece, acrylic foldable toric intraocular lens (IOLs) and conventional implantation using an ophthalmic viscosurgical device (OVD). METHODS: In this study, 60 eyes with cataract and preexisting regular corneal astigmatism of 1.0 to 3.0 diopters (D) underwent the implantation of the AcrySof toric IOLs (Alcon Laboratories, Inc.). The patients were randomly assigned to a conventional implantation technique with an OVD or a hydroimplantation technique. Comparison of preoperative and postoperative parameters was performed using paired Student t tests, and independent Student t test was used to compare between the two groups. RESULTS: Three months postoperatively, the mean subjective astigmatism was 0.45 D ± 0.24 (SD) in the OVD group and 0.49 ± 0.29 D in the hydroimplantation group (P = 0.492). The mean endothelial cell density (ECD) loss was 7.54% ± 0.82% and 7.32% ± 0.59%, respectively (P = 0.117). The mean absolute IOL rotation was 4.77 ± 2.32 degrees and 4.70 ± 1.95 degrees, respectively (P = 0.334). The mean time for IOL implantation was 71.50 ± 8.10 s and 37.60 ± 3.90 s, respectively (P < 0.001). Two hours, 1 day, 1 week, 1 month, and 3 months postoperatively, there was no significant difference in IOP between the two groups (P > 0.05), although IOP two hours postoperatively seemed to be a little higher in the OVD group. CONCLUSIONS: Compared with the use of OVDs for toric IOLs implantation, the hydroimplantation technique provided advantages of increased efficiency, reduced surgical time and cost, and no concerns of OVD-induced elevated IOP. TRIAL REGISTRATION: Current Controlled Trials ISRCTN55696872 , Retrospectively registered (Date of registration: 25 March 2018).

The P20R mutation of αB-crystallin diminishes its anti-apoptotic activity in human lens epithelial cells.

αB-crystallin acts as an anti-apoptosis protein in human lens epithelial (HLE) cells. We recently identified a missense mutation in αB-crystallin that changes proline 20 to an arginine (P20R) in a Chinese family with autosomal dominant congenital posterior polar cataract. The impact of the P20R mutation on the anti-apoptosis function remains unclear. To explore the anti-apoptotic activity of αB-crystallin wild type (αB-wt) and its P20R mutant under oxidative stress, HLE cells were transfected with αB-wt and αB-P20R constructs and expression was measured by western blotting. Flow cytometry and terminal deoxynucleotidyl transferase (TdT)-mediated dUTP digoxigenin nick end-labelling (TUNEL) staining were performed to investigate apoptosis. We found that αB-wt performed a dominant role in inhibiting stress-induced apoptosis, but this function was impeded in cells expressing αB-P20R. The P20R mutant of αB-crystallin exhibits diminished anti-apoptotic activity compared with the native protein.

Can Down-gaze During Near Work Cause Peripheral Deprivation in Asian Eyes?

PURPOSE: We hypothesize that the typically narrower palpebral apertures of East Asian eyes in combination with the narrowing of this aperture during down-gaze combine to reduce light levels and image contrast in the inferior retina during near work, thus creating peripheral deprivation in these eyes that could generate deprivation myopia in children culturally encouraged to perform near work. METHODS: We photographed the right eyes of 53 Chinese children during down-gaze (from 10 to 40 degrees) from the fixation point and the primary gaze position. From these images, we determined the size and shape of the effective foveal and superior field entrance pupil at different down-gaze angles. By using an eye model with typical levels of off-axis higher-order aberrations, we quantified the impact of eyelid and eyelash vignetting of the pupil on both retinal illuminance and image quality using Visual Strehl Ratio (VSOTF), and the non-visually weighted Strehl Ratio (SROTF). RESULTS: The effective aperture for the superior visual field is vignetted during down-gaze by lids and lashes, producing reductions in retinal illuminance of 30% and >60% at 20 and 40 degrees, respectively. However, the aperture vignetting effect on peripheral image modulation is small, with neural and aberration changes dominating image quality in the superior field during down-gaze. CONCLUSIONS: Occlusion of the pupil by eyelid and eyelashes during down-gaze is unlikely to produce significant superior field deprivation in East Asian eyes.

Comparison of femtosecond laser-assisted deep anterior lamellar keratoplasty and penetrating keratoplasty for keratoconus.

BACKGROUND: To compare outcomes of femtosecond laser-assisted deep anterior lamellar keratoplasty (FSL-DALK) and penetrating keratoplasty (FSL-PK) for the treatment of keratoconus. METHODS: Twenty eight eyes underwent FSL-DALK (consisted of 12 eyes in the FSL-DALKa subgroup without baring the Descemet's membrane and 16 eyes in the FSL-DALKb subgroup baring the Descemet's membrane using big-bubble technique) were compared with 12 eyes that underwent FSL-PK for keratoconus. These patients underwent an ophthalmic examination preoperatively and 3, 6, 9, and 12 months postoperatively. RESULTS: The postoperative BCVA in the FSL-PK group, and the FSL-DALKb subgroup were significantly better than that in the FSL-DALKa subgroup (P < 0.05), whereas no differences were found between the FSL-DALKb subgroup and the FSL-PK group (P > 0.05). There were no significant differences in the mean spherical equivalent (SE) and astigmatism between the FSL-DALK and the FSL-PK groups, nor between the subgroups of FSL-DALK during the follow-up period (P > 0.05). At the last follow-up, the mean endothelial cell loss in the FSL-DALK group (9.12 %) was significantly less than that in the FSL-PK group (20.79 %) (P < 0.001), while there was no difference between the FSL-DALKa (9.15 %) and the FSL-DALKb (9.10 %) subgroups (P = 0.15). The FSL-DALK group seemed to have fewer graft rejections (1/28 cases) than the FSL-PK group (2/12 cases), although Kaplan-Meier curve showed no significant difference between the two groups (P = 0.144). CONCLUSIONS: In this retrospective study, the results suggested that FSL-DALKb gives better visual outcome, and FSL-DALKb is a better option for keratoconus whose endothelium is not compromised. However, larger and prospective studies are further required.

[Treatment of large corneal perforations with acellular multilayer of corneal stromal lenticules harvested from femtosecond laser lenticule extraction].

OBJECTIVE: To describe a novel surgical technique for the treatment of large corneal perforations by using acellular multilayer of corneal stromal lenticules. METHODS: Prospective study. The acellular tissue used for the repair was harvested from myopic patients during the femtosecond laser (FS) refractive surgery. Informed consent, blood test and donor eligibility were obtained in each case. Three or four layers of lenticules were stacked up and stored at -80°C in pure sterile glycerin. The diameter is 6.0 to 6.5 mm and central thickness was 300 to 400 µm. If the diameter of the corneal ulcer perforation was larger than 3 mm and corneal grafts were not available, we used this kind of patches to seal the perforations. It was a retrospective case series study. Five cases of corneal ulcer perforation were enrolled in this study. One was neuropathic keratitis, one was atopic keratoconjunctivitis, and the other three were fungal keratitis. Acellular multilayer of stromal lenticules were used in these cases for emergent therapy. RESULTS: The sealing of the perforation and the re-establishment of the anterior chamber were achieved successfully in all the cases. For the pericentral perforations, visual recovery was achieved. And efficient palliative management was done for the central perforations. CONCLUSIONS: The reported technique seems to represent a good alternative emergency procedure for the management of large corneal perforations. It is a very useful method for Chinese hospitals where the shortage of cornea donors is a very serious problem and the amount of FS surgeries are increasing.

A novel COL4A1 gene mutation results in autosomal dominant non-syndromic congenital cataract in a Chinese family.

BACKGROUND: Almost one-third of congenital cataracts are primarily autosomal dominant disorders, which are also called autosomal dominant congenital cataract, resulting in blindness and clouding of the lens. The purpose of this study was to identify the disease-causing mutation in a Chinese family affected by bilateral, autosomal dominant congenital cataract. METHODS: The detection of candidate gene mutation and the linkage analysis of microsatellite markers were performed for the known candidate genes. Molecular mapping and cloning of candidate genes were used in all affected family members to screen for potential genetic mutations and the mutation was confirmed by single enzyme digestion. RESULTS: The proband was diagnosed with isolated, congenital cataract without the typical clinical manifestations of cataract, which include diabetes, porencephaly, sporadic intracerebral hemorrhage, and glomerulopathy. A novel mutation, c.2345 G > C (Gly782Ala), in exon 31 of the collagen type IV αlpha1 (COL4A1) gene, which encodes the collagen alpha-1(IV) chain, was found to be associated with autosomal dominant congenital cataract in a Chinese family. This mutation was not found in unaffected family members or in 200 unrelated controls. Sequence analysis confirmed that the Gly782 amino acid residue is highly conserved. CONCLUSIONS: The novel mutation (c.2345 G > C) of the COL4A1 gene is the first report of a non-syndromic, autosomal dominant congenital cataract, thereby highlighting the important role of type IV collagen in the physiological and optical properties of the lens.

Antigenic variability among two subtypes of human adenovirus serotype 7.

Human adenovirus type 7 (HAdV-7) is one of the major serotypes responsible for acute respiratory infection. It is important to investigate the antigenic variabilities of different HAdV-7 genomic subtypes for vaccine development. Phylogenetic analysis of global HAdV-7 strains and major antigen proteins showed that HAdV-7 could be classified into two subtypes. There were three highly variable regions (HVR1, HVR4, and HVR7) in the hexon protein that varied between subtypes. Within each of the subtypes, these regions were conserved. Two subtype HAdV-7 strains isolated in China were used to immunize mice for antigenic characterization. Mice immunized with one subtype strain showed 4-8-fold lower neutralizing antibody titers against another subtype strain. ELISA results showed that the variation in HVR1, 4, and 7 regions contributed to antigenic change, and it may be concluded that the three regions contain subtype-specific epitopes. In summary, strains of HAdV-7 could be divided into two subtypes using genome sequence and antigenic analysis; our results could be important for HAdV-7 vaccine development.

A novel P20R mutation in the alpha-B crystallin gene causes autosomal dominant congenital posterior polar cataracts in a Chinese family.

BACKGROUND: To identify the genetic defects and investigate the possible mechanism of cataract genesis in a five-generation family with autosomal dominant congenital posterior polar cataracts. METHODS: Clinical data were collected, and the lens phenotypes of the affected members in this family were recorded by slit lamp photography. Genomic DNA was isolated from peripheral blood using QIAamp DNA Blood Mini Kits. Twenty-three mutational hot spots associated with autosomal dominant congenital posterior polar cataracts were screened by PCR-based DNA sequencing. Properties and structural models of wild-type and mutant alpha-B (αB)-crystallin (CRYAB) were generated and analyzed using SWISS-MODEL. RESULTS: All affected individuals in this family started to exhibit poor vision at the age of 8-10 years. The lens opacity consisted of a single, well-defined plaque, 0.5-3 mm in diameter, which was confined to the posterior pole of the lens. DNA sequencing analysis of the affected members showed a novel, heterozygous missense mutation c.59C > G (P20R) in exon 1 of the CRYAB gene. This mutation was not found in 10 unaffected family members, or in 200 unaffected and unrelated individuals, thereby excluding the possibility that it is a rare polymorphism. Data generated using the ProtScale and PyMOL programs revealed that the mutation altered the stability and solubility of the αB-crystallin protein. CONCLUSIONS: This study reported a novel c.59C > G (P20R) missense mutation in CRYAB in a five-generation Chinese family with posterior polar cataract.

Association of magnetic resonance imaging-derived sarcopenia with outcomes of patients with hepatocellular carcinoma after hepatectomy.

PURPOSE: To evaluate whether sarcopenia, diagnosed by magnetic resonance imaging (MRI) protocol, constitutes a prognosis-associated risk factor in patients with hepatocellular carcinoma (HCC) after hepatectomy. METHODS: One hundred and ninety-three patients who underwent hepatectomy for HCC were retrospectively enrolled. The areas of the total skeletal muscle (SM) and psoas muscle (PM) were evaluated at the third lumbar vertebra in the preoperative MR images, and divided by the square of height in order to obtain the skeletal muscle index (SMI) and psoas muscle mass index (PMI). Sarcopenia was diagnosed respectively on the definitions based on the SMI or PMI. The potential of muscle-defined sarcopenia as a prognostic factor for overall survival (OS) and recurrence-free survival (RFS) was investigated in these patients. RESULTS: The areas of SM and PM, and SMI and PMI were significantly higher in the men than in the women (all p < 0.05). Notably, SMI-defined sarcopenia displayed a significant sex difference (p = 0.003), while PMI-defined sarcopenia did not (p = 0.370). Through univariate and multivariate analyses, PMI-defined sarcopenia remained an independent predictor for OS and RFS (HR = 3.486, 95% CI: 1.700-7.145, p = 0.001 and HR = 1.993, 95% CI: 1.246-3.186, p = 0.004), even after adjusting for other clinical variables. Moreover, Kaplan-Meier analysis demonstrated significantly poorer OS and RFS for patients with sarcopenia defined by using PMI, but not SMI, compared to those without sarcopenia (p < 0.001 and p = 0.006, respectively). CONCLUSION: MRI-derived, sarcopenia defined by using PMI, not SMI, may serve as a significant risk factor for RFS and OS in patients with HCC after hepatectomy.

Clinical value of combined predictors of RET%, γ-GT, LDH in the ABO neonatal hemolytic disease.

Objective: The purpose of this study is to examine the prognostic significance of the amalgamated indicators, reticulocyte percentage (RET%), lactate dehydrogenase (LDH), and γ-Glutamyltransferase (γ-GT), in neonatal ABO hemolytic disease. Methods: A total of 137 hospitalized children with pathological jaundice were included. Based on their medical conditions, they were categorized into two groups, hemolytic (67 cases) and non-hemolytic (70 cases). Pearson linear correlation and binary logistic multivariate analysis were used to analyze LDH, γ-GT, RET% and hemolysis. Furthermore, the predictive value of the combined predictors of RET%, LDH, and γ-GT on ABO neonatal hemolytic disease was evaluated using the ROC curve analysis. Results: The laboratory indexes of the two groups were subject to analysis using binary logistic regression to identify suspicious influencing factors. The study revealed that RET%, LDH, and γ-GT were independent risk factors for hemolysis. Pearson linear correlation analysis indicated a positive correlation between LDH and γ-GT with RET% (r = 0.529, P < 0.01; r = 0.526, P = <0.01, respectively). Furthermore, the predictive value of each combined predictor was obtained using the ROC curve, and it was observed that combined predictor L (RET% + LDH + γ-GT)>L1 (RET% + LDH)>L2 (RET% + γ-GT). Conclusion: Combined predictor L (RET% + LDH + γ-GT)demonstrate its optimal diagnostic efficacy, offering a novel approach towards diagnosing early-onset ABO hemolytic disease of the newborn.

Characterization of a Novel Gja8 (Cx50) Mutation in a New Cataract Rat Model.

Purpose: To describe a novel spontaneous cataract inbred strain isolated from large-scale breeding SD rats, identify the responsible gene mutation, and understand how this mutation affects lens function. Methods: Exome sequencing of 12 cataract-associated genes was performed in the affected and healthy relatives. Sequences of rat wild-type or mutant gap junction protein alpha 8 gene (Gja8) were transfected into cells. The expression level of protein was assayed by Western blot analysis. Subcellular localization of connexin 50 (Cx50) was analyzed in confocal fluorescent images. Wound-healing, 5-ethynyl-2'-deoxyuridine incorporation, and attachment assay were performed to characterize the cell migration, proliferation and adhesion. Results: The abnormality was found to be inheritable in an autosomal semi-dominant pattern through different mating patterns. We found a G to T transversion at codon 655 in Gja8, leading to a substitution of valine by phenylalanine (p.V219F). Gja8V219F/+ heterozygotes expressed nuclear cataract while Gja8V219F/V219F homozygotes manifested microphthalmia in addition to cataract. Histology revealed fiber disorders and loss of organelle-free zone in the mutant lens. Cx50V219F altered its location in HeLa cells and inhibited the proliferation, migration and adhesion abilities of HLEB3 cells. The mutation also reduced the expression of focal adhesion kinase and its phosphorylation. Conclusions: The c.655G>T mutation (p.V219F) is a novel mutation in Gja8, inducing semi-dominant nuclear cataracts in a new spontaneous cataract rat model. The p.V219F mutation altered Cx50 distribution, inhibited lens epithelial cell proliferation, migration, and adhesion, and disrupted fiber cell differentiation. As a consequence, the nuclear cataract and small lens formed.

Protective effects of ferulic acid against ionizing radiation-induced oxidative damage in rat lens through activating Nrf2 signal pathway.

AIM: To examine the protection of ferulic acid (FA) against ionizing radiation (IR)-induced lens injury in rats, as well as the underlying mechanisms. METHODS: FA (50 mg/kg) was administered to rats for 4 consecutive days before they were given 10 Gy γ-radiation, as well as for 3 consecutive days afterward. Two weeks after radiation, the eye tissues were collected. Histological alterations were evaluated by hematoxylin-eosin staining. Enzyme linked immunosorbent assay (ELISA) was utilized to assess the activities of glutathione reductase (GR) and superoxide dismutase (SOD), as well as the levels of glutathione (GSH) and malondialdehyde (MDA) in the lenses. The protein and mRNA levels of Bcl-2, caspase-3, Bax, heme oxygenase-1 (HO-1), and glutamate-cysteine ligase catalytic subunit (GCLC) were quantified using Western blot and quantitative reverse transcription polymerase chain reaction, respectively. With nuclear extracts, the nuclear factor erythroid-2 related factor (Nrf2) protein expressions in the nuclei were also measured. RESULTS: Rats exposed to IR showed lens histological alterations which could be alleviated by FA. FA treatment reversed apoptosis-related markers in IR-induced lens, as evidenced by lower levels of Bax and caspase-3 and higher level of Bcl-2. Furthermore, IR induced oxidative damage manifested by decreased GSH level, increased MDA level, and decreased SOD and GR activities. FA boosted nuclear translocation of Nrf2 and increased the expressions of HO-1 and GCLC to inhibit oxidative stress, as evidenced by an increase in GSH, a decrease in MDA, and an increase in GR and SOD activities. CONCLUSION: FA may work well in preventing and treating IR-induced cataract through promoting the Nrf2 signal pathway to attenuate oxidative damage and cell apoptosis.

Screening the pathogenic causes of congenital cataract via whole exome sequencing technology in three families: Molecular genetics of congenital cataract.

Congenital cataract is the commonest cause of visual impairment and blindness in children worldwide. Among congenital cataract cases, ~25% are caused by genetic defects, while several genetic mutations have been identified in hereditary cataract. In the present study, a patient with cataract underwent clinical ophthalmic examination and pedigree analysis. Whole exome sequencing and Sanger sequencing were performed to identify and verify gene mutations. The frequency, conservation, pathogenicity and hydrophobicity of the mutated amino acids were analyzed by bioinformatics analysis. The clinical examination and investigation verified that the probands of family A and C suffered from nuclear cataracts. In addition, the proband of family B was diagnosed with white punctate opacity. The pattern of inheritance was autosomal dominant. The sequencing analysis results revealed a mutation c.592-c593insG (p.W198Wfs*22) in exon 6 of CRYBA1/A3, a known mutation c.463C > T (p.Q155X) in exon 6 of CRYBB2 and a third mutation c.865­c.866insC (p.T289Tfs*91) in exon 2 of GJA8. Each variant was co­segregated with disease in family And the mutation frequency in the database was <0.01. It has been reported that the mutation sites are highly conserved among different species, thus greatly affecting the sequence and structure of a protein, while exhibiting high pathogenicity in theory. The two crystallin gene mutations could notably enhance the local hydrophobicity of the protein, eventually resulting in its reduced solubility and destruction of lens transparency. The current study identified pathogenic genes in three families with congenital cataract and analyzed the association between mutation sites and different cataract phenotypes. Overall, the results could expand the genotype spectrum of congenital cataract and provide evidence for its clinical diagnosis.

Computed tomography imaging features to evaluate the severity of portal hypertension and predict the rebleeding risk after endoscopic treatment in cirrhotic patients with variceal hemorrhage.

PURPOSE: To investigate the association of computed tomography (CT) imaging features and severity of portal hypertension (PH) and develop a nomogram to predict high-risk PH in cirrhotic patients with gastroesophageal variceal hemorrhage (GVH). METHODS: The study retrospectively enrolled 158 cirrhotic patients with a history of endoscopic treatment for GVH. Hepatic vein pressure gradient (HVPG) was measured and the patients were classified into high-risk (HVPG > 16 mmHg) or low-risk (HVPG ≤ 16 mmHg) PH group. Pre-treatment CT features, including cavernous transformation of portal vein (CTPV), hilar periportal space (a distance between right portal vein and posterior edge of segment IV of the liver), and depth of right posterior hepatic notch sign (a sharp indentation in the right medial posterior liver surface), were evaluated. Risk factors associated with high-risk PH were analyzed, and a nomogram based on the imaging features was developed. RESULTS: High-risk PH group showed a higher rebleeding rate after treatment than that of the low-risk (P = 0.029). Multivariate analysis indicated that larger hilar periportal space (P < 0.001), less frequencies of CTPV (P = 0.044) and deeper right posterior hepatic notch (P < 0.001) were independent risk factors associated with high-risk PH. A nomogram based on the three CT imaging features was established to predict high-risk PH with an excellent discrimination (c-statistic 0.854). CONCLUSION: The nomogram based on CT features of hilar periportal space, depth of right posterior hepatic notch and CTPV can help to distinguish cirrhotic patients with high-risk PH, who are more vulnerable of variceal rebleeding after endoscopic treatment.