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Summary: Arabidopsis lines with loss-of-function mutation in Embryo sac-specific Pectin MethylEsterase Inhibitor (Atepmei) gene showed seed sterility with embryo sac cellularization defects. Examination of tissue-cleared mature ovules revealed irregularly positioned nuclei/embryos within the embryo sacs. Egg cell-specific marker (DD45) expression analysis confirmed the presence of multiple egg cells in the mutant embryo sacs. These supernumerary egg cells were functional as evident from the production of twin embryos when supernumerary sperm cells were provided. The results of ruthenium red and tannic acid–ferric chloride staining of developing Atepmei mutant ovules showed that cell wall formation and maintenance were altered around embryo sac nuclei, which also coincided with change in the gamete specification. This report implicates the role of cell walls in gamete cell fate determination by altering cell-cell communication. Our analysis of the twin-embryo phenotype of epmei mutants also sheds light on the boundary conditions for double fertilization in plant reproduction.

The root-knot nematode (RKN), Meloidogyne incognita, is an obligate, sedentary endoparasite that infects a large number of crops and severely affects productivity. The commonly used nematode control strategies have their own limitations. Of late, RNA interference (RNAi) has become a popular approach for the development of nematode resistance in plants. Transgenic crops capable of expressing dsRNAs, specifically in roots for disrupting the parasitic process, offer an effective and efficient means of producing resistant crops. We identified nematode-responsive and root-specific (NRRS) promoters by using microarray data from the public domain and known conserved cis-elements. A set of 51 NRRS genes was identified which was narrowed down further on the basis of presence of cis-elements combined with minimal expression in the absence of nematode infection. The comparative analysis of promoters from the enriched NRRS set, along with earlier reported nematode-responsive genes, led to the identification of specific cis-elements. The promoters of two candidate genes were used to generate transgenic plants harboring promoter GUS constructs and tested in planta against nematodes. Both promoters showed preferential expression upon nematode infection, exclusively in the root in one and galls in the other. One of these NRRS promoters was used to drive the expression of splicing factor, a nematode-specific gene, for generating host-delivered RNAi-mediated nematode-resistant plants. Transgenic lines expressing dsRNA of splicing factor under the NRRS promoter exhibited upto a 32% reduction in number of galls compared to control plants.

Background: Hypericum is a well-known plant genus in herbal medicine. Hypericum mysorense (Family: Hypericaceae), a plant belonging to the same genus, is well known in folklore medicine for its varied therapeutic potential. Objective: The aim of the present study was to investigate the different parts of the plant for antioxidant and hepatoprotective properties. Materials and Methods: The methanol extracts of Hypericum mysorense prepared from various parts of the plant were tested in vitro for their free radical scavenging activity against ABTS• (diammonium salt), DPPH• (1,1-diphenyl-2-picrylhydrazyl), NO•, O2•− and •OH radicals, using standard systems of assays. The total antioxidant capacity, total phenolic and total flavonoid content of the extracts were analyzed. Further, the leaf and flowering top extracts were tested for their in vivo antioxidant and hepatoprotective activities on Wistar rats using a carbon tetrachloride-induced hepatic injury model. Results: The leaf and flowering top extract showed potent antioxidant activity and also possessed highest total phenolic and flavonoid content. The antioxidant activity and the total phenolic and flavonoid content present in these extracts showed a good correlation. The leaf and flowering top extracts at 200 mg/kg restored aspartate amino transferase (ASAT), alanine amino transferase (ALAT), alkaline phosphatase (ALP), total bilirubin and protein levels significantly in CCl4-intoxicated rats. The tested extracts also showed a significant (p < 0.001) reduction in 2-thiobarbituric acid reactive substance (TBARS) levels with an increase in SOD and CAT levels. The histopathology of liver did not show any toxicity after the treatment with the extracts. The active extracts were standardized using two marker compounds, hyperoside and rutin, which were isolated from the plant by HPLC. HPLC studies revealed that the maximum concentration of hyperoside and rutin is present in the flowering top extract.

Chickpea (Cicer arietinum) is the second most widely grown legume worldwide and is the most important pulse crop in the Indian subcontinent. Chickpea productivity is adversely affected by a large number of biotic and abiotic stresses. MicroRNAs (miRNAs) have been implicated in the regulation of plant responses to several biotic and abiotic stresses. This study is the first attempt to identify chickpea miRNAs that are associated with biotic and abiotic stresses. The wilt infection that is caused by the fungus Fusarium oxysporum f.sp. ciceris is one of the major diseases severely affecting chickpea yields. Of late, increasing soil salinization has become a major problem in realizing these potential yields. Three chickpea libraries using fungal-infected, salt-treated and untreated seedlings were constructed and sequenced using next-generation sequencing technology. A total of 12,135,571 unique reads were obtained. In addition to 122 conserved miRNAs belonging to 25 different families, 59 novel miRNAs along with their star sequences were identified. Four legume-specific miRNAs, including miR5213, miR5232, miR2111 and miR2118, were found in all of the libraries. Poly(A)-based qRT-PCR (Quantitative real-time PCR) was used to validate eleven conserved and five novel miRNAs. miR530 was highly up regulated in response to fungal infection, which targets genes encoding zinc knuckle- and microtubule-associated proteins. Many miRNAs responded in a similar fashion under both biotic and abiotic stresses, indicating the existence of cross talk between the pathways that are involved in regulating these stresses. The potential target genes for the conserved and novel miRNAs were predicted based on sequence homologies. miR166 targets a HD-ZIPIII transcription factor and was validated by 5' RLM-RACE. This study has identified several conserved and novel miRNAs in the chickpea that are associated with gene regulation following exposure to wilt and salt stress.

Purpose: To study intravitreal brolucizumab in the management of persistent macular fluid in chronic central serous chorioretinopathy (CSCR) without choroidal neovascular membrane (CNVM)., Methods: Retrospective case series which included eyes with chronic CSCR with persistent macular fluid for ≥ 3 months without CNVM. Intravitreal brolucizumab was administered in all eyes. Primary outcome measure was the resolution of intraretinal (IRF) and/or subretinal fluid (SRF) on OCT., Results: Five eyes (four patients) with chronic CSCR were included. All eyes showed complete resolution of SRF 1 month following injection. Minimal residual IRF was present in two eyes. Best corrected visual acuity (BCVA) was stable in three eyes, and two eyes showed improvement. Central macular thickness (CMT) and subfoveal choroidal thickness (SFCT) showed reduction., Conclusion: Intravitreal brolucizumab is effective in the rapid reduction of persistent macular fluid in chronic CSCR without CNVM. Long-term follow-up data are required to study recurrence and adverse effect profile.

Purpose: Hazy media with resultant difficulties in visualisation hamper the surgical approach and outcomes in various vitreoretinal surgical scenarios, including eyes with keratoprosthesis in situ. We propose a novel chandelier-assisted bimanual infusion using a flute needle to overcome the inability to secure infusion safely in such eyes., Methods: The surgical technique was performed with the assistance of chandelier illumination. The irrigation tubing from the vitrectomy machine was connected to a flute needle for infusion. A bimanual technique was utilized with the flute needle connected to infusion in one hand and the cutter in the other hand., Results: A 34-year-old monocular male patient with a keratoprosthesis in his seeing eye developed late-onset endophthalmitis with retroprosthetic membranes. The visual acuity had dropped from 20/20 to hand motions. Our novel bimanual technique helped secure infusion safely for vitrectomy. The patient recovered well to a visual acuity of 20/60 with a good anatomical outcome., Conclusion: Early vitrectomy may be essential for ensuring optimal outcomes in certain eyes with endophthalmitis. Surgical intervention in eyes with keratoprosthesis with secondary endophthalmitis is challenging due to difficulties in visualisation. This was overcome in our case with a novel bimanual chandelier-assisted technique for securing infusion., Competing Interests: Conflict of interest: Nil

Aim: To report the clinical settings and factors predicting outcomes in scleral tears with concurrent retained intraocular foreign bodies METHODS: All cases with scleral and corneoscleral wounds with retained intraocular foreign bodies (RIOFB) from January 2014 to January 2021 were retrospectively analysed. Favourable anatomic outcome was defined as presence of globe integrity, attached retina, absence of hypotony and active inflammation at last visit. Favourable functional outcome was defined as final visual acuity (VA) > 20/200., Results: Total 139 eyes were included. Mean age was 30.66 ± 13.32 years (median 29 years, IQR 17). Penetrating trauma accounted for 87.1%, rupture for 5.8%, perforation for 7.2%. In 5.8% of the eyes the injury involved zone I extending till Zone II while in 66.9% it involved Zone II and in 27.3% in Zone III. Snellen visual acuity at presentation was logMAR 2.97 ± 1.01 and at last visit was logMAR 2.38 ± 1.45 (p < 0.0001). Time between presentation and repair was 13.93 ± 19.56 h (median 7.6 h, IQR 17.17). Favourable functional outcome was seen in 34.5% eyes and 2/3rd achieved favourable anatomic outcome. Absence of endophthalmitis (OR = 6.25, p = 0.003) and ability to remove the foreign body (OR = 7.05, p = 0.003) were associated with a favourable anatomic outcome. Better presenting Snellen visual acuity (OR = 2.77, p = 0.003), manifest scleral tear (OR = 3.36, p = 0.04), and absence of endophthalmitis (OR = 50, p = 0.0009) were associated with a favourable functional outcome., Conclusion: A third of the cases achieved favourable visual outcome while 2/3rd achieved favourable anatomic outcome. Absence of endophthalmitis is an important factor predicting both., (© 2023. The Author(s), under exclusive licence to The Royal College of Ophthalmologists.)

Retinotomy refers to "cutting" or "incising" the retina, whereas retinectomy denotes "excising" the retina. Retinotomies and retinectomies aid in tackling traction and retinal shortening that persist following membrane dissection and scleral buckling. We performed a literature search using Google Scholar and PubMed, followed by a review of the references procured. All relevant literature was studied in detail and summarized. We discuss the indications of retinotomies and retinectomies for relaxing retinal stiffness, accessing the subretinal space for choroidal neovascular membrane, hemorrhage and abscess clearance, drainage retinotomies to allow retinal flattening, radial retinotomies to release circumferential traction, harvesting free retinal grafts, and prophylactic chorioretinectomies in trauma., Competing Interests: Declaration of Competing Interest Hung-Da Chou is a consultant for Novartis, Bayer, AbbVie, and Viatris. Sengul Ozdek is a consultant for Roche, Bayer, Novartis, and AbbVie. Andrew Chang is a consultant for Alcon, Novartis, Bayer, Hoffman La Roche, Apellis, and Allergan. Paisan Ruamviboonsuk is a consultant for Roche and Bayer. Rest of the authors report no disclosures., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Purpose: To report the clinical settings, management and factors affecting outcomes in multi-drug resistant (MDR) and extensively-drug resistant (XDR) Pseudomonas endophthalmitis., Settings: Retrospective, consecutive, non-comparative interventional case series. Cases of MDR and XDR Pseudomonas endophthalmitis from January 2012 to December 2020 treated at our tertiary eye care center were included. Data collected included clinical data, anatomic and functional outcome, isolated micro-organisms, and culture sensitivity., Results: This study included 29 eyes of 29 patients with MDR/XDR Pseudomonas endophthalmitis. Mean age at presentation was 60.27 ± 14.9 years (median 63). Commonest clinical setting was acute post-operative endophthalmitis in 27 cases (93.1%). Concurrent corneal infiltrate was present in 11 eyes (37.9%). Initial intervention in 19 eyes (65.5%) was vitrectomy, 2 of which underwent endoscopic pars plana vitrectomy. Mean number of interventions was 3.34 ± 1.44 (median 4). Mean follow up was 3.25 ± 3.07 months (median 2). Sensitivity to ceftazidime was 48.28%. All isolates were sensitive to colistin. Mean visual acuity at last follow up in logMAR was 2.64 ± 1.48 (median 3.5). Seven eyes (24.13%) were NPL (nil perception of light) at the last follow up. Two eyes (6.9%) underwent evisceration. Nine eyes (31.03%) had a favourable anatomic and functional outcome. Eyes without a corneal infiltrate at presentation were found to have a favourable anatomic and favourable functional outcome (OR 11.91, P < 0.04, CI 1.08 to 130.93)., Conclusion: Corneal involvement at presentation is associated with poorer outcomes in MDR and XDR Pseudomonas endophthalmitis. There is a potential role of higher newer antibiotics especially colistin in the management of these cases.

Purpose: Modern vitreo-retinal surgery has scaled new frontiers with the advent of better instrumentation. However, physiological tremors, intraocular dexterity and difficulty in visualization hamper minimally invasive retinal surgery. Robotics has the potential to overcome these limitations and improve surgical outcomes. This review aims to provide a comprehensive summary of the advances made in the field of robotics in vitreo-retinal surgery., Methods: This review included 30 studies comprising randomized control trials, nonrandomized comparative studies and systematic reviews on the application of robotics in vitreo-retinal surgery., Results: Robotic systems presently available in vitreo-retinal surgery can be broadly classified based on the extent of automation into five categories: robot-assisted, co-manipulated, tele-operated, partially/fully automated and magnetically controlled devices. Key features of individual devices are highlighted in this review. Robotic assistance in vitreo-retinal surgery can maximize performance for routine procedures, enable high-precision procedures such as targeted gene therapy and retinal vein cannulation, improve ergonomics, and revolutionize tele-surgery. Cost limitations and compatibility with available surgical systems are the barriers in implementation of robotics in retinal microsurgery., Conclusion: This review provides a concise summary of the available robotic systems in vitreo-retinal surgery, advantages over conventional systems, current applications and future implications. Robotics is a rapidly evolving field, which holds great promise in the future of vitreo-retinal surgery.