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Inherited retinal diseases (IRDs) comprise a phenotypically and genetically heterogeneous group of ocular disorders that cause visual loss via progressive retinal degeneration. Here, we report the genetic characterization of 1210 IRD pedigrees enrolled through the Japan Eye Genetic Consortium and analyzed by whole exome sequencing. The most common phenotype was retinitis pigmentosa (RP, 43%), followed by macular dystrophy/cone- or cone-rod dystrophy (MD/CORD, 13%). In total, 67 causal genes were identified in 37% (448/1210) of the pedigrees. The first and second most frequently mutated genes were EYS and RP1, associated primarily with autosomal recessive (ar) RP, and RP and arMD/CORD, respectively. Examinations of variant frequency in total and by phenotype showed high accountability of a frequent EYS missense variant (c.2528GA). In addition to the two known EYS founder mutations (c.4957dupA and c.8805CG) of arRP, we observed a frequent RP1 variant (c.5797CT) in patients with arMD/CORD.

There are few reports of the adoption of continuous processes in bioproduction, particularly the implementation of end-to-end continuous processes, due to difficulties such as feed adjustment, production batch demarcation, and incorporating virus filtration. Here, we propose an end-to-end continuous process for a monoclonal antibody (mAb) with three integrated process segments: upstream production processes with pool-less direct connection, pooled low pH virus inactivation with automated pH control and a total flow-through integrated polishing process in which two columns were directly connected with a virus filter. The pooled virus inactivation step demarcates the batch, and high impurities reduction and mAb recovery were achieved for batches conducted in succession. Viral clearance tests also confirmed robust virus reduction for the flow-through two column chromatography and the virus filtration steps. Additionally, viral clearance tests with two different hollow fiber virus filters operated at flux ranging from 1.5 to 40 LMH confirmed robust virus reduction over these ranges. Complete clearance with LRV ≥ 4 was achieved even with a process pause at the lowest flux. The end-to-end continuous process proposed in this study is highly applicable to production processes, and the investigated virus filters have excellent applicability to continuous processes conducted at constant flux.

Background: Recent advancements in cell engineering and bioreactor engineering have enabled high monoclonal antibody (mAb) concentrations in harvested solutions for the downstream process (DSP). Methods: As many unit operations such as capture chromatography, polish chromatography, membrane filtration, virus inactivation, virus filtration, and concentration by ultrafiltration are involved in DSP, it is crucial to monitor the process carefully in order to perform reliable and stable DSP operations. One of the most important signals (process parameter) to be monitored is the protein concentration CP. Although various methods are available, most of them are not suited for measuring high CP. In this paper, we have developed a method for measuring very high CP by optical rotation (OR). Result: Linear correlations were confirmed between OR and CP in the range CP = 0 to 80 g/L for mAbs with high repeatability and small variation coefficients. This method was applied to the monitoring of CP in the opaque (colored) solution during the cell culture. The CP by OR was in good agreement with those by the standard Protein A HPLC method. Conclusion: Monitoring of high CP by OR is expected to be an efficient process analytical tool (PAT) for DSP.

Purpose. To determine the effects of cataract surgery on contrast visual acuity and retinal sensitivity in patients with retinitis pigmentosa. Methods. Retinal sensitivity and contrast visual acuity were determined by microperimetry (MAIA) and contrast sensitivity acuity tester (CAT-CP), respectively, before and after cataract surgery. The significance of the correlations between visual acuity, retinal sensitivity, contrast visual acuity, improvements after surgery, and macular structure before and after cataract surgery was determined. Results. Retinal sensitivity and contrast visual acuity were significantly improved after cataract surgery. The correlations among postoperative visual acuity, postoperative retinal sensitivities, and preoperative ellipsoid zone length were significant. The postoperative retinal sensitivity of the central 10° and the ellipsoid zone length was particularly significantly correlated. Preoperative contrast visual acuity and the amount of improvement and preoperative retinal sensitivity and the amount of improvement were significantly negatively correlated. The contrast visual acuity under both the 100% and 10% photopic and mesopic conditions improved significantly after cataract surgery. Conclusions. Cataract surgery in retinitis pigmentosa patients with preserved ellipsoid zones significantly improved retinal sensitivity and contrast visual acuity. Cataract surgery can be expected to improve retinal sensitivity and contrast visual acuity under various conditions, even if preoperative visual parameters are low, as long as the ellipsoid zone is preserved.

With growing demands for therapeutic monoclonal antibodies, in silico downstream process development based on mechanistic modeling of chromatography separation process is being increasingly used for process optimization and process characterization. Application of mechanistic modeling in biopharmaceutical industry has been sparse due to the significant investment of time and resources that are required for performing model calibration. Mechanistic modeling of the chromatography process involves a large number of mass transport and binding parameters and their initial input values are required for simulations. These input values of column parameters can be easily obtained either from experiments or from empirical correlations available in literature. On the other hand, obtaining the model input valves for binding kinetic parameters is usually a cumbersome process as it involves performing batch experiments which are not only tedious but also require significant quantities of purely isolated main product and its related impurities, which is challenging as the product related impurities are typically present in smaller quantities and hence are difficult to obtain as pure species. In the present work, a mechanistic model that is based on the general rate model coupled with extended Langmuir binding model has been used for prediction of linear gradient elution peaks of monoclonal antibody on cation exchanger chromatography. The present work describes an accelerated approach for obtaining the input values for binding kinetic parameters in the extended Langmuir binding model from the two Yamamoto coefficient A and B values obtained by Yamamoto method directly from the model calibration linear gradient elution runs of different gradient slopes and at low to moderate protein loadings. The equations that can relate the two coefficients to the extended Langmuir model equation binding kinetic parameters were derived. Therefore, once A and B are determined, the binding kinetic parameter values were determined straightforward, thereby avoiding the problem of multiple solutions for the model parameters. The estimated binding parameters were successfully validated from isocratic elution experiments performed at low loading. What we demonstrate is that the proposed approach allows us to estimate binding kinetic parameters in a significantly more efficient and accelerated manner than presently used approaches, thereby accelerating development and implementation of mechanistic modeling for process chromatography.

Aims: Diabetic macular edema (DME) leads to impaired vision. The first line of treatment is intravitreal injection of anti-vascular endothelial growth factor (VEGF) agent. However, there are patients who are refractory to this. We reported patients whose DME were refractory to anti-VEGF agents and showed improvement by using sodium glucose cotransporter 2 inhibitors (SGLT2is) . The effectiveness of SGLT2is for DME was assessed using a health insurance claim database. Methods: The JMDC inc. database covering million Japanese patients between 2005-20was used for analysis. Patients with type 2 diabetes (T2D) with DME were included, and those who were undergo dialysis, had other ocular diseases that may be treated by anti-VEGF agents, or were not on treatment with any antidiabetic drug introduced after 2014 were excluded. Propensity score matching was performed between SGLT2i users and non-users. The frequency and the duration of intravitreal injection of anti-VEGF agent after the period from the start of SGLT2is or other antidiabetic drugs were analyzed. Results: In this study, 340 matched patients with T2D were analyzed. Initiation of SGLT2is revealed a decrease in the frequency of anti-VEGF agent injection (2.7 ± 4.1 vs. 3.8 ± 4.6 times, p < 0.001; the Wilcoxon signed rank test, p < 0.001, 95%CI -0.25 to -0.085; the Poisson regression, p < 0.001, HR 0.80, 95% CI 0.73 to 0.87; the recurrent event analysis) and an extension in the duration for the requirement of the first injection of anti-VEGF agent (the number of patients who received no anti-VEGF agents, 96 vs. 32, p < 0.001; the log-rank test) . Conclusion: Using SGLT2is for patients with T2D complicated by DME extended the duration for the requirement of the first anti-VEGF agent injection and decreased the frequency of anti-VEGF agent injection. SGLT2is may be an option for DME treatment. Disclosure R.Ishibashi: Research Support; Astellas Pharma Inc., Boehringer Ingelheim International GmbH, Daiichi Sankyo, Mitsubishi Tanabe Pharma Corporation, Taiho Pharmaceutical Co. Ltd., YL Biologics, ZERIA Pharmaceutical Co.,Ltd. E.Kawakami: None. M.Koshizaka: None. Y.Maezawa: None. K.Yokote: None. Y.Takatsuna: None. T.Tatsumi: None. S.Yamamoto: None. Y.Inaba: None. Y.Shiko: None.

We reviewed medical records of 121 patients/235 eyes of typical retinitis pigmentosa (RP) patients who could be followed up for at least 5 years with the aim of investigating the long-term course of visual function progression at each RP stage and appropriate assessment methods. Patients were classified into three groups: mild RP ( baseline mean deviation MD ≥ − 5 ), moderate RP ( − 25 < baseline MD < − 5 ), and late RP ( baseline MD ≤ − 25 ). Linear mixed-effect models were used to follow MD, the average retinal sensitivity of the central four points of the Humphrey field analyzer 10-2 program (S4), and visual acuity (VA) with increasing time. The associations among factors (baseline MD group, sex, hereditary form) and the interaction between each factor and time were also investigated. The mean reduction of the MD, S4, and VA for all patients was -0.37 dB/year, -0.25 dB/year, and 0.018/year, respectively. The moderate RP group had a faster progression than other groups in MD (-0.43 dB/year, p < 0.05 ). The moderate (-0.31 dB/year, p = 0.01 ) and late RP groups (-0.25 dB/year, p < 0.01 ) had faster progression than the mild RP group in S4. The late RP group had faster progression in VA than the other groups (0.03/year, p < 0.05 ). Females had a slower progression of the S4 (-0.15 dB/year, p = 0.02 ) and VA (0.01/year, p < 0.001 ) than males. The autosomal dominant group had a slower progression than the sporadic group in MD (-0.22 dB/year, p = 0.02 ); the autosomal dominant and autosomal recessive groups had a slower VA decline than the sporadic group (0.01/year, p = 0.03 ; 0.01/year, p = 0.04 ). Because the progression rates of VA and visual field test differed as per the RP stage, S4 and VA can also be useful assessment methods depending on the stage. Inheritance form and sex may affect the progression rate.

IntroductionPreviously, we conducted a clinical trial to evaluate the safety and efficacy of transdermal electrical stimulation (TdES) with skin electrodes to improve the visual functions in patients with retinitis pigmentosa (RP). No adverse events were related to the treatment during follow-up examinations, and TdES significantly improved the mean visual acuity and visual field sensitivity.Methods and analysisWe developed a study protocol for a prospective, multicentre, randomised, double-masked and sham-controlled clinical trial, planned to commence on June 2021. We intend to compare the maintenance or improvement in best-corrected visual acuity, and safety of TdES using skin electrodes between patients with RP and the sham group. The primary endpoint comprises the superiority of the logarithm of the minimum angle of resolution (logMAR) visual acuity change at week 24 from baseline in the treatment and sham groups. Secondary endpoints involve the comparison of the treatment and sham groups at week 24 for the logMAR visual acuity, early treatment diabetic retinopathy study visual acuity, the mean deviation value of Humphrey field analyser 10-2, monocular Humphrey Esterman visual field test score, ellipsoid zone length, central foveal thickness and 25-item National Eye Institute Visual Function Questionnaire score. We intend to enrol 50 patients from three Japanese institutions within 1 year and follow them up for 1 years.Ethics and disseminationThe protocol was approved by the institutional review board at the Chiba University Hospital and two other institutions, and was registered with the Japan Registry of Clinical Trials on 17 May 2021. The trial will be conducted in accordance with the principles of the Declaration of Helsinki, and is in accordance with Good Clinical Practice standards. The findings will be published in a peer-reviewed journal.Trial registration numberJRCT2032210094.

Background and objectives Studies have shown that COVID-19 school closures negatively impacted children’s well-being. We assessed the impact of school closures on children in Japan. We postulated that screen time and sleep habits during school closure would be associated with children’s mental health status. Methods A cross-sectional study was conducted with 959 children in four public elementary schools. Parents completed an original questionnaire in which we enquired about children’s behavioral problems, screen time (duration of watching TV/videos and duration of playing video games), sleep habits, and bodyweight change during school closure. Logistic regression analyses were performed to investigate the relationships between behavioral problems, bodyweight gain, and screen time. Results It was found that 50.3% of children exhibited some behavioral problems during school closure; fewer children exhibited such problems after schools reopened. Moreover, children’s behavioral problems during school closure were associated with longer total screen time (odds ratio [OR]: 1.2, 95% confidence interval [CI]: 1.14–1.28, p < .001). Sleep habits were not different between children with behavioral problems and those without. Of the children, 16.7% experienced bodyweight gain during school closure, which was associated with behavioral problems (OR: 2.0, 95% CI: 1.43–2.92, p < .001) and time spent watching TV/videos (OR: 1.2, 95% CI: 1.08–1.28, p < .001) during closure. Conclusions COVID-19 school closure negatively impacted school children physically and psychologically. Screen time was associated with both physical and mental health status. Therefore, children should not engage in arbitrary screen time during school closures and should be supported in their daily routines.

Shallow coastal ecosystems are reservoirs of carbon derived from allochthonous organic matter and autochthonous organic matter produced by microalgae and macrophytes. Carbon stored in vegetated coastal ecosystems has attracted broad attention as an important component of carbon sinks. Characterizing the source of carbon in sediments is essential for quantifying the carbon-sequestration function of shallow coastal ecosystems. In this study, we investigated the origins of organic matter using organic biomarkers (lignin phenols, fatty acids, cutin acids, diacids, and ω-hydroxy acids) in surface sediments in a seagrass-dominated lagoon (Furen Lagoon, Japan). Biomarkers derived from allochthonous vascular plants, such as long-chain fatty acids, showed higher concentrations near river mouths. Furthermore, biomarker signals indicated that sedimentary organic carbon originated in large part from degraded allochthonous vascular plants including roots. A Bayesian mixing model using the ratios of syringyl phenols to vanillyl phenols and cinnamyl phenols to vanillyl phenols indicated that up to about 65% of lignin in the sediments was derived from seagrass. This result indicates a substantial contribution of seagrass to the sedimentary lignin pool in an estuarine seagrass meadow. However, the percent contribution of seagrass to the lignin pool varied, with higher values near a tidal inlet and relatively low values near river mouths. Vertical profiles of organic biomarkers varied with the differences in degradability of organic compounds. Specifically, long-chain fatty acids decreased with increasing depth more than the other compounds, suggesting that they degraded more easily. Conversely, we observed a tendency for lignin phenols to be selectively preserved in the vertical sediment profiles. Our results show that sediment organic biomarkers can provide diverse information such as the composition and origins of organic carbon, the contribution of seagrass derived lignin, and the varying degrees of decomposition. This approach should bring new insights to the estimation of carbon in future blue carbon studies.