Efficacy of vitreoretinal surgery in the treatment of X-linked retinoschisis with serious complications

AIM: To evaluate the efficacy of vitreoretinal surgery in the treatment of X-linked retinoschisis(XLRS)and its complications. <p>METHODS: A retrospective study was made on all the XLRS patients with severe complications after operation in this hospital. All the 25 patients(31 eyes)present with macular abnormalities with/without peripheral retina split bypreoperative OCT examination. Among the 31 eyes, there were 7 eyes with vitreous hemorrhage, 8 eyes with retinal detachment and vitreous hemorrhage, and 16 eyes with rhegmatogenous retinal detachment. All the 31 eyes were divided into 2 groups: group A included 15 eyes which underwent photocoagulation before the surgery, while the other 16 eyes in group B didn't perform photocoagulation before the surgery. All the patients underwent a pars plana vitrectomy without lensectomy associated with internal limiting membrane peeling. Photocoagulation was done to the retinal holes and degeneration areas in group A. Gas or silicone oil was filled in group B after retinal photocoagulation treatment. Three years later, analysis was made on the results of the visual acuity, postoperative anatomical and functional outcome in these 2 groups. Statistical analysis was made on the results of average visual acuity before and after operation by SPSS software method, the difference was statistically significant(<i>P</i><0.05). The differences of changes of visual acuity in two groups were statistically significant by one-way analysis of variance method. <p>RESULTS: Postoperative anatomical and functional outcome were satisfied at the last visit. A total of 23 eyes'(74.2%)visual acuity were improved with the mean visual acuity increasing from 0.13±0.08 to 0.24±0.16, the difference was statistically significant(<i>t</i>=-5.354,<i>P</i>=0.000). The average visual acuity in group A was improved from 0.11±0.08 to 0.22±0.15 after operation(<i>t</i>=-4.391, <i>P</i>=0.000). While the average visual acuity in group B increased from 0.14±0.08 to 0.26±0.15(<i>t</i>=-4.488, <i>P</i>=0.000). The visual changes in two groups were statistical significance. But when compared the average changes of visual acuity before and after operation between two groups, <i>F</i>=4.055, <i>P</i>=0.069, there was no statistical significance. During the following-up period, the complications were found in three eyes, among which two eyes presented with proliferative vitroretinopathy and traction retinal detachment 10 and 12 months after surgery, and one eye presented with cataract 3 months after surgery. Two eyes belonged to group A while the third eye pertain to group B. After reoperation, all the three eyes have good prognosis and retinoschisis didn't worsen.<p>CONCLUSION: Vitreoretinal surgery can be applied to the treatment of X-linked congenital retinoschisis and its complication, effectively preventing the deterioration of schisis cavity and contributing to the improvement and stabilization of visual acuity and resuming the anatomic structure of retina

Clinical observations of vitreoretinal surgery for four different phenotypes of X-linked congenital retinoschisis

AIM: To evaluate the outcomes of vitreoretinal surgery for four different phenotypes of X-linked retinoschisis (XLRS). METHODS: This study included thirty-one eyes of 25 patients who developed XLRS with severe complications. Among the 31 eyes, there were 7 eyes with vitreous hemorrhage, 8 eyes with retinal detachment and vitreous hemorrhage, and 16 eyes with rhegmatogenous retinal detachment. All of the patients underwent standard three-port pars plana vitrectomy. All of the eyes were divided into 4 groups before surgery according to a modified classification scheme, with the first three groups as follows: group A, with foveal cystic schisis; group B with macular lamellar schisis; and group C with foveolamellar changes. Peripheral schisis was not present in these 3 groups; however, group D was a complex group with both macular and peripheral changes. One year after surgery, we analyzed the best corrected visual acuity and postoperative anatomical and functional outcomes of these 4 groups. RESULTS: There were 7 eyes in group A (22.6%), 1 eye in group B (3.2%), 15 eyes in group C (48.4%) and 8 eyes in group D (25.8%). Postoperative anatomical and functional outcomes were satisfactory at the last visit, while the mean visual acuity was increased to 0.27±0.11, with a significant difference (t=-1.049, P=0.000) compared with the results before surgery (0.1±0.08). Visual acuity was improved in 23 eyes (74.2%). Complications were found in three eyes: two eyes with proliferative vitreoretinopathy and traction retinal detachment 10 and 12mo after surgery, respectively; and one eye with vitreous hemorrhage 15mo after surgery. These eyes were in groups C and D. The retinas remained attached in these 3 eyes after reoperation. CONCLUSION: We should pay greater attention to XLRS with foveolamellar changes because it is the most changeable phenotype. Once complications occur, vitreoretinal surgery can significantly improve visual acuity and restore the anatomic structure of the retina

An energy planning oriented method for analyzing spatial-temporal characteristics of electric loads for heating/cooling in district buildings with a case study of one university campus

Highlights A method to analyze spatial-temporal characteristics of district loads was developed. PCA was used to identify the buildings greatly affecting district load management. The features of electric loads of heating on a university campus were analyzed. Building type and operation mode greatly affect the load level and volatility. Abstract Accurate grasp of district power demand is of great significance to both sizing of district power supply and its operation optimization. In this study, an index system has been established and visualized through a Geographic Information System, for revealing both temporal and spatial characteristics of district power loads caused by heating/cooling systems, including load level and fluctuation characteristics, spatial distribution of electric loads, and load coupling relationships between individual buildings and the district. Principal component analysis was applied to identify the buildings with significant impact on district load management. Using this method, the spatial-temporal characteristics of electric loads caused by heating in one university campus in China were analyzed. The results showed that building type and the operation modes had great effects on the level and volatility of the district electric load caused by heating. Buildings with high load levels and strong coupling with the peak district electric load, such as academic buildings, often had a major impact on the power demand of the district. Therefore, they were considered as key targets for energy-saving renovation and operation optimization. Buildings with large load fluctuation, such as teaching buildings, could contribute to the peak load shaving by adjusting the heating systems’ operation

Mitochondrial Dysfunction in Neural Injury

Mitochondria are the double membrane organelles providing most of the energy for cells. In addition, mitochondria also play essential roles in various cellular biological processes such as calcium signaling, apoptosis, ROS generation, cell growth, and cell cycle. Mitochondrial dysfunction is observed in various neurological disorders which harbor acute and chronic neural injury such as neurodegenerative diseases and ischemia, hypoxia-induced brain injury. In this review, we describe how mitochondrial dysfunction contributes to the pathogenesis of neurological disorders which manifest chronic or acute neural injury

Identification and drug metabolic characterization of four new CYP2C9 variants CYP2C9*72-*75 in the Chinese Han population

Cytochrome 2C9 (CYP2C9), one of the most important drug metabolic enzymes in the human hepatic P450 superfamily, is required for the metabolism of 15% of clinical drugs. Similar to other CYP2C family members, CYP2C9 gene has a high genetic polymorphism which can cause significant racial and inter-individual differences in drug metabolic activity. To better understand the genetic distribution pattern of CYP2C9 in the Chinese Han population, 931 individuals were recruited and used for the genotyping in this study. As a result, seven synonymous and 14 non-synonymous variations were identified, of which 4 missense variants were designated as new alleles CYP2C9*72, *73, *74 and *75, resulting in the amino acid substitutions of A149V, R150C, Q214H and N418T, respectively. When expressed in insect cell microsomes, all four variants exhibited comparable protein expression levels to that of the wild-type CYP2C9 enzyme. However, drug metabolic activity analysis revealed that these variants exhibited significantly decreased catalytic activities toward three CYP2C9 specific probe drugs, as compared with that of the wild-type enzyme. These data indicate that the amino acid substitution in newly designated variants can cause reduced function of the enzyme and its clinical significance still needs further investigation in the future

SIRT1 deacetylates SATB1 to facilitate MARHS2-MARε interaction and promote ε-globin expression

The higher order chromatin structure has recently been revealed as a critical new layer of gene transcriptional control. Changes in higher order chromatin structures were shown to correlate with the availability of transcriptional factors and/or MAR (matrix attachment region) binding proteins, which tether genomic DNA to the nuclear matrix. How posttranslational modification to these protein organizers may affect higher order chromatin structure still pending experimental investigation. The type III histone deacetylase silent mating type information regulator 2, S. cerevisiae, homolog 1 (SIRT1) participates in many physiological processes through targeting both histone and transcriptional factors. We show that MAR binding protein SATB1, which mediates chromatin looping in cytokine, MHC-I and β-globin gene loci, as a new type of SIRT1 substrate. SIRT1 expression increased accompanying erythroid differentiation and the strengthening of β-globin cluster higher order chromatin structure, while knockdown of SIRT1 in erythroid k562 cells weakened the long-range interaction between two SATB1 binding sites in the β-globin locus, MARHS2 and MARε. We also show that SIRT1 activity significantly affects ε-globin gene expression in a SATB1-dependent manner and that knockdown of SIRT1 largely blocks ε-globin gene activation during erythroid differentiation. Our work proposes that SIRT1 orchestrates changes in higher order chromatin structure during erythropoiesis, and reveals the dynamic higher order chromatin structure regulation at posttranslational modification level