An ecotoxicological assessment of a strigolactone mimic used as the active ingredient in a plant biostimulant formulation.

A risk assessment on the aquatic toxicity of the plant biostimulant strigolactone mimic (2-(4-methyl-5-oxo-2,5-dihydro-furan-2-yloxy)-benzo[de]isoquinoline-1,3-dione (SL-6) was performed using a suite of standardised bioassays representing different trophic groups and acute and chronic endpoints. In freshwater, three trophic groups of algae, crustacea and fish were used. Whilst in seawater, algae (unicellular and macroalgae), Crustacea and Mollusca were employed. In addition, the genotoxicity of SL-6 was determined with the comet assessment performed on unicellular marine algae, oysters, and fish embryos. This was the first time ecotoxicity tests have been performed on SL-6. In freshwater, the lowest LOEC was measured in the unicellular algae at 0.31 mg/L SL-6. Although, similar LOEC values were found for embryo malformations and impacts on hatching rate in zebrafish (LOEC 0.31-0.33 mg/L). Consistent malformations of pericardial and yolk sac oedemas were identified in the zebrafish embryos at 0.31 mg/L. In marine species, the lowest LOEC was found for both Tisbe battagliai mortality and microalgae growth at an SL-6 concentration of 1.0 mg/L. Significant genotoxicity was observed above control levels at 0.0031 mg/L SL-6 in the unicellular algae and 0.001 mg/L SL-6 in the oyster and zebrafish larvae. When applying the simple risk assessment, based on the lowest NOECs and appropriate assessment factors, the calculated predicted no effect concentration (PNEC), for the ecotoxicity and the genotoxicity tests were 1.0 µg/L and 0.01 µg/L respectively.

CENTRAL AND PERIPHERAL INVOLVEMENT OF THE RETINA IN THE INITIAL STAGES OF DIABETIC RETINOPATHY.

PURPOSE: To determine the degree of central microvascular closure using optical coherence tomography angiography in eyes of patients with type 2 diabetes with visible lesions only in the central retina or only in the periphery. METHODS: Cross-sectional study. All 127 eyes underwent ultra-widefield fundus photography 200° examinations with OPTOS California (Optos, Dunfermline, United Kingdom) and Cirrus Angioplex optical coherence tomography angiography 3 × 3 mm acquisitions (ZEISS, Dublin, CA). RESULTS: Twenty-five eyes showed visible lesions only in the central retina, 57 only in the peripheral retina, and 45 presented visible lesions in entire retina. The group with visible lesions only in the periphery showed definite closure in the superficial capillary plexus in 49% of the eyes, whereas the group with visible lesions only in the central seven-early treatment diabetic retinopathy study fields area showed a definite closure in 64%. CONCLUSION: Central capillary closure is already present in the initial stages of diabetic retinopathy even when lesions are only visible in the peripheral retina. Capillary closure in the superficial capillary plexus is three times more frequent than in the deep capillary plexus, demonstrating earlier closure of the superficial capillary plexus. Eyes with visible lesions only in the periphery show a milder form of retinopathy.

Amniotic membrane graft after excision of widespread conjunctival concretions / Enxerto de membrana amniótica após remoção de concreções conjuntivais

ABSTRACT Conjunctival concretions are single or clustered lesions frequently found on the palpebral conjunctiva. They are commonly present in older individuals, despite being rarely symptomatic. This case report describes an 83-year-old man with multiple conjunctival concretions, which were surgically treated. The patient was symptomatic on presentation and did not respond to conservative treatment. For this reason, a surgical approach was considered. After wide excision of the conjunctival lesions, a piece of amniotic membrane was fitted using fibrin glue. During follow-up, a markedly improvement in patient's symptoms was observed, along with nearly complete absence of conjunctival concretions. This is the first case report addressing extensive conjunctival concretions with a surgical approach using amniotic membrane. The authors conceived the technique described after noticing the limited clinical options in the literature. This technique was easily performed and achieved satisfactory results.

RESUMO As concreções conjuntivais representam lesões amareladas, simples ou múltiplas, frequentemente encontradas na conjuntiva palpebral. São mais prevalentes em idades avançadas e raramente sintomáticas. Este relato de caso descreve o quadro clínico de um paciente de 83 anos com múltiplas concreções conjuntivais, cirurgicamente tratadas. Por se tratar de um paciente sintomático com resposta insuficiente ao tratamento conservador, foi considerada a abordagem cirúrgica. Após remoção das lesões, foi aplicado um enxerto de membrana amniótica, adaptado com cola de fibrina. No acompanhamento pós-operatório, verificou-se melhoria significativa dos sintomas, com desaparecimento quase total das concreções conjuntivais. Este é o primeiro caso que descreve uma abordagem cirúrgica com utilização de membrana amniótica na resolução desse tipo de lesões. A técnica, de fácil execução e com resultados muito favoráveis, foi desenvolvida pelos autores após constatarem a escassez de alternativas na literatura.