Principles of amyloplast replication in the ovule integuments of Arabidopsis thaliana.

Plastids in vascular plants have various differentiated forms, among which amyloplasts are crucial for starch storage and plant productivity. Despite the vast knowledge of the binary-fission mode of chloroplast division, our understanding of the replication of non-photosynthetic plastids, including amyloplasts, remains limited. Recent studies have suggested the involvement of stromules (stroma-filled tubules) in plastid replication when the division apparatus is faulty. However, details of the underlying mechanism(s) and their relevance to normal processes have yet to be elucidated. Here, we developed a live analysis system for studying amyloplast replication using Arabidopsis (Arabidopsis thaliana) ovule integuments. We showed the full sequence of amyloplast development and demonstrated that wild-type amyloplasts adopt three modes of replication, binary fission, multiple fission, and stromule-mediated fission, via multi-way placement of the FtsZ ring. The minE mutant, with severely inhibited chloroplast division, showed marked heterogeneity in amyloplast size, caused by size-dependent but wild-type modes of plastid fission. The dynamic properties of stromules distinguish the wild-type and minE phenotypes. In minE cells, extended stromules from giant amyloplasts acquired stability, allowing FtsZ ring assembly and constriction, as well as the growth of starch grains therein. Despite hyper-stromule formation, amyloplasts did not proliferate in the ftsZ null mutant. These data clarify the differences between amyloplast and chloroplast replication and demonstrate that the structural plasticity of amyloplasts underlies the multiplicity of their replication processes. Furthermore, this study shows that stromules can generate daughter plastids via assembly of the FtsZ ring.

Melatonin: Unveiling the functions and implications in ocular health.

Melatonin, a versatile hormone produced by the pineal gland, has garnered considerable scientific interest due to its diverse functions. In the eye, melatonin regulates a variety of key processes like inhibiting angiogenesis by reducing vascular endothelial growth factor levels and protecting the blood-retinal barrier (BRB) integrity by enhancing tight junction proteins and pericyte coverage. Melatonin also maintains cell health by modulating autophagy via the Sirt1/mTOR pathways, reduces inflammation, promotes antioxidant enzyme activity, and regulates intraocular pressure fluctuations. Additionally, melatonin protects retinal ganglion cells by modulating aging and inflammatory pathways. Understanding melatonin's multifaceted functions in ocular health could expand the knowledge of ocular pathogenesis, and shed new light on therapeutic approaches in ocular diseases. In this review, we summarize the current evidence of ocular functions and therapeutic potential of melatonin and describe its roles in angiogenesis, BRB integrity maintenance, and modulation of various eye diseases, which leads to a conclusion that melatonin holds promising treatment potential for a wide range of ocular health conditions.

N6-methyladenosine methylation in ophthalmic diseases: From mechanisms to potential applications.

N6-methyladenosine (m6A) modification, as the most common modification method in eukaryotes, is widely involved in numerous physiological and pathological processes, such as embryonic development, malignancy, immune regulation, and premature aging. Under pathological conditions of ocular diseases, changes in m6A modification and its metabolism can be detected in aqueous and vitreous humor. At the same time, an increasing number of studies showed that m6A modification is involved in the normal development of eye structures and the occurrence and progress of many ophthalmic diseases, especially ocular neovascular diseases, such as diabetic retinopathy, age-related macular degeneration, and melanoma. In this review, we summarized the latest progress regarding m6A modification in ophthalmic diseases, changes in m6A modification-related enzymes in various pathological states and their upstream and downstream regulatory networks, provided new prospects for m6A modification in ophthalmic diseases and new ideas for clinical diagnosis and treatment.

Bibliometric evaluation of global trends and characteristics of RNA methylation during angiogenesis.

Background: RNA methylation is involved in major life processes. Angiogenesis is a normal phenomenon that occurs constantly in the bodies of all mammals, once it is aberrant or something goes wrong, it may lead to pathological changes. The bibliometric analysis could produce a comprehensive overview of RNA methylation during angiogenesis. Methods: The Web of Science Core Collection (WoSCC) database was used to screen publications about RNA methylation during angiogenesis from Jan 1, 2000 to Nov 24, 2022. Bibliometric and visualization analyses were conducted to understand publication trends by CiteSpace and VOSviewer. Results: In total, 382 publications from 2000 to 2022 were included in the bibliometric and visualization analyses. On the whole, the number of publications had exponential growth. China was the country and Sun Yat-Sen University was the university associated with the largest number of publications, although publications from the United Kingdom and Soochow University were currently having the strongest impact. Cancer was the most studied topic in this field, and N6-methyladenosine is the most studied RNA methylation type. Conclusion: There is a continuously increasing trend in publications related to RNA methylation and angiogenesis, which has attracted much attention, particularly since 2011. RNA methylation might be a promising target in the investigation of pathological angiogenesis and related disorders, which deserves further investigation.

Treatment Outcomes in Patients with Conjunctival Mucosa-Associated Lymphoid Tissue (MALT) Lymphoma.

Purpose: To report the outcomes of different therapies in patients with conjunctival mucosa-associated lymphoid tissue (MALT) lymphoma. Patients and Methods: This retrospective study included patients diagnosed with conjunctival MALT lymphoma between August 2000 and April 2022. Patients were classified into three groups according to their treatment: an observation group, a radiation therapy (RT) group, and a rituximab group (rituximab with or without chemotherapy). We analyzed overall survival (OS), overall, local, and systemic relapse-free survival (RFS), and adverse events after treatment. Results: This study included 15 patients (22 eyes). The 10-year OS was 100%. The 2-, 5-, and 10-year overall RFS rates were 80.1%, 41.2%, and 41.2% in all patients, respectively. The 2- and 5-year local RFS rates in the observation group were 100% and 0%, respectively. The 2-, 5-, and 10-year local RFS rates were 87%, 87%, and 87% in the RT group and 83%, 67%, and 67% in the rituximab group, respectively. The 2- and 5-year systemic RFS rates in the observation group were both 100%, and the 2-, 5-, and 10-year systemic RFS rates were 92%, 55%, and 55% in the RT group, and 100%, 60%, and 60% in the rituximab group, respectively. After RT, 53.3% of the eyes developed cataracts and 75% of these were treated with cataract surgery. In addition, 53.3% of the eyes developed dry eyes and were treated with eye drops. Rituximab with or without chemotherapy resulted in some systemic adverse events, but these improved following symptomatic therapies. Conclusion: RT resulted in good local control of conjunctival MALT lymphoma; however, systemic relapse may occur during long-term follow-up. Local and/or systemic relapse may also occur during long-term follow-up in patients treated by observation or rituximab with or without chemotherapy. Patients with conjunctival MALT lymphoma should be followed-up carefully for as long as possible after treatment.

Ten-year outcomes of congenital cataract surgery performed within the first six months of life.

PURPOSE: To investigate the long-term outcomes of congenital cataract surgery performed within the first 6 months of life. SETTING: 11 ophthalmic surgical sites in Japan. DESIGN: Retrospective chart review. METHODS: Medical charts were retrospectively reviewed for 216 eyes of 121 patients. The age at surgery was 2.9 ± 1.7 months, with follow-up duration 13.0 ± 2.3 years. The cohort consisted of 83 cases with bilateral aphakia, 12 with bilateral pseudophakia, 20 with unilateral aphakia, and 6 with unilateral pseudophakia. RESULTS: Surgical intervention within the critical period of visual system development (10 weeks for bilateral and 6 weeks for unilateral cases) led to significantly better final visual acuity than surgery conducted after this time frame. The incidence of secondary glaucoma was similar between groups while the occurrence of visual axis opacification was more frequent with earlier surgery. A forward stepwise multiple regression analysis revealed that the final visual acuity was significantly associated with laterality of cataract (better outcomes in bilateral cases), phakic status (with pseudophakia outperforming aphakia), presence of systemic and ocular comorbidities, and development of secondary glaucoma. Secondary glaucoma was significantly more prevalent in aphakic eyes than pseudophakic eyes. CONCLUSIONS: In patients with genuine congenital cataract, surgery within the critical period of visual development results in better final visual acuity, albeit with an increased risk of visual axis opacification. The use of IOL with sophisticated surgical techniques shows promise even in congenital cataract surgery.

Incidence and prognosis of taxane-induced macular edema: a retrospective study from the Japan Clinical REtina Study Group (J-CREST).

Macular edema is a known side effect of taxane-based anticancer drugs. We retrospectively investigated data from 11 centers between January 2016 and December 2021. Among 14,260 patients, 30 (0.21%) developed macular edema; from these, the number of cases associated with nab-paclitaxel was 16 (0.43%), significantly higher than the number of cases associated with paclitaxel or docetaxel (P < 0.01). Visual acuity (VA) and retinal choroidal change were examined in 27 patients, with a follow-up of at least 3 months. The patients' mean age was 67.2 years; 14 (51.3%) were male and four (14.8%) had unilateral onset. The mean interval between anticancer drug initiation and the first ophthalmology visit was 290.1 days. Among the 20 patients who discontinued anticancer drugs, VA and edema significantly improved 2 months after discontinuation (LogMAR VA: 0.50 vs. 0.28, central retinal thickness: 472.7 µm vs. 282.5 µm, both P < 0.01). No significant changes were observed in the central choroidal thickness. A correlation was found between duration of taxane treatment and VA immediately before discontinuation of anticancer drugs (ß = 0.00050; 95% confidence interval: 0.00036-0.00097; P < 0.05). Although taxane-induced macular edema is reversible, slower anticancer drug discontinuation worsened VA, highlighting the need for regular ophthalmologic evaluation during treatments.

Characterization of the visually impaired patients with diabetes mellitus in Japan.

AIMS/INTRODUCTION: To conduct a multicenter survey of visually impaired patients with diabetes mellitus (DM) and to identify the physical and ocular characteristics that lead to blindness in Japan. MATERIALS AND METHODS: Visually impaired patients with diabetes mellitus in Japan were divided into blind and low-vision groups according to the World Health Organization classification. Data on parameters related to diabetes mellitus and ocular complications in the right and left eyes were collected from 19 highly advanced medical facilities and compared between the two groups. RESULTS: Among 408 visually impaired persons (blind group: 257, low-vision group: 151), 72.1% were under 70 years of age. The rates of neovascular glaucoma (NVG) (right eye, P = 0.041; left eye, P = 0.0031) or proliferative diabetic retinopathy (PDR) (right eye: P = 0.014, left eye: P = 0.0047) and the rate of proliferative membrane beyond half of the retinal area (right eye: P = 0.0263, left eye: P = 0.037) were significantly higher in the blind group. The direct cause of visual impairment was retinal atrophy, common in both groups. Neovascular glaucoma and diabetic macular edema were equally prevalent in the blind and low-vision groups, respectively. CONCLUSIONS: In Japan, blind patients with diabetes mellitus are characterized by severe conditions such as neovascular glaucoma and progressive proliferative diabetic retinopathy upon their initial visit to an advanced care facility. These results highlight the importance of monitoring retinopathy through regular ophthalmological examinations, internal medicine, and appropriate therapeutic intervention.