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Plant symbiotic fungi (endophytes) of the genus Neotyphodium [anamorphs, asexual derivatives of Epichloë (Ascomycota: Clavicipitaceae)] often associate with grass species of the subfamily Pooideae, which includes important forage and turf species. These endophytes are known to produce a range of alkaloids that enhance their host's resistance to insects or are toxic to grazing animals. Among the alkaloids, loline alkaloids (saturated 1-aminopyrrolizidines) are generally observed in the highest concentrations in many Neotyphodium–grass symbiotic associations, and are known to be toxic to insects but not to mammals. Some Neotyphodium-infected grasses have enhanced resistance to rice leaf bug, Trigonotylus caelestialium (Kirkaldy) (Heteroptera: Miridae), one of the major pests for rice production in Japan. Our laboratory experiments quantified the effects of purified loline ( N-formylloline) and in planta synthesis of loline alkaloids by meadow fescue [ Lolium pratense (Huds.) S.J. Darbyshire (syn. Festuca pratensis Huds.)]– Neotyphodium uncinatum (Gams, Petrini & Schmidt) Glenn, Bacon & Hanlin and Italian ryegrass ( Lolium multiflorum Lam.)– Neotyphodium occultans Moon, Scott & Christensen associations on the development and survival of T. caelestialium. No-choice feeding assays with laboratory populations of the insect revealed that their growth was significantly decreased by the infected grasses, and the effect was greater for N. uncinatum than for N. occultans, in keeping with differences in N-formylloline concentrations in the plants. Artificial feeding of N-formylloline through feeding sachets indicated that the chemical has an adverse effect on survival of larvae, even at the lowest concentration tested (50 µg/g), which was considerably lower than the typical concentrations in many Neotyphodium–grass association s. The results confirmed the ability of Neotyphodium-infected forage grasses to control T. caelestialium propagation in meadows, which may cause damages to nearby rice paddies. [ABSTRACT FROM AUTHOR]

Neotyphodiumfungal endophytes form mutualistic symbiotic associations with many grasses of the subfamily Pooideae, including important forage and turfgrass species. This relationship provides a competitive advantage to the host plant by increasing abiotic/biotic stress tolerance, such as its resistance to drought, diseases, and insect pests. The insect deterrent effects of endophytes are now receiving attention in Japan, as insect pests growing in meadows are causing problems in adjacent rice paddies. One of the most serious problems is the kernel spotting of rice grains caused by the rice leaf bug,Trigonotylus caelestialiumKirkaldy (Heteroptera: Miridae), which reproduces onLoliumspecies grown as forage. To determine the potential ofNeotyphodiumendophytes to reduce the invasion of rice crops byT. caelestialiumfrom adjacentLoliumcrops, we carried out choice and no-choice feeding tests using endophyte-infected and endophyte-free clonal perennial ryegrass (Lolium perenneL.) (Poaceae). Our experiments revealed that the presence of theNeotyphodiumendophyte strongly deterred the feeding of both first-instar larvae and adults ofT. caelestialium. These results show the potential ofNeotyphodiumendophytes to reduce the number ofT. caelestialiumin forage fields and grasslands, and thus to reduce the damage to rice grains caused by this insect pest. [ABSTRACT FROM AUTHOR]

The article discusses a study to evaluate the use of functional magnetic resonance imaging (fMRI) to help evaluate the impact of refractive surgery like Laser-Assisted in Situ Keratomileusis (LASIK) on vision beyond the posterior eye segment. The findings indicate that it may take several months for the neural basis of adaptation to new vision following refractive surgery and fMRI may help in understanding influence of surgery. Some of the other outcomes following the study are highlighted.

Purpose: To investigate the anterior segment morphology in cataracts with Retinitis Pigmentosa (RP)., Setting: XXXX (anonymized for review) University Hospital., Design: A retrospective matched case-control study., Methods: The analysis included 28 eyes of 28 patients with cataracts and RP and 28 eyes of 28 patients with cataracts but without RP, matched for age and sex. Lens thickness, anterior lens curvature (Front R), posterior lens curvature, anterior chamber depth (ACD), anterior chamber width, central corneal thickness (CCT), white-to-white distance (WTW), corneal curvature, and axial length (AL) were compared between the groups. Data were obtained from preoperative evaluations conducted before cataract surgery. The same set of comparisons was also conducted for 18 eyes of 18 patients with cataracts and RP and 18 eyes of 18 patients with cataracts but without RP, matched for age, sex, and AL. Cases including missing data, categorized as Emery-Little classification grade 4 or above, or those with a history of acute angle closure were excluded., Results: In the age- and sex-matched analysis, cataracts with RP showed significantly a thicker lens, steeper Front R, shallower ACD, thinner CCT, and shorter AL. In the analysis matched by age, sex, and AL, cataracts with RP had a thicker lens, steeper Front R, and larger WTW., Conclusions: Cataracts with RP demonstrated centripetal swelling of the lens, centrifugal corneal thinning, and AL shortening. A decrease in tension between the lens and eyeball wall due to zonular weakness in the RP may lead to swelling of the lens and horizontal flattening of the eyeball., (Copyright © 2024 Published by Wolters Kluwer on behalf of ASCRS and ESCRS.)

Purpose: To report a case of button battery-induced alkaline burn injury of the cornea and conjunctiva, with experimental findings of local damage., Case: A three-year-old girl had a hard and polished white opacity on the nasal lower cornea and conjunctival injection, caused by a button battery remaining in the conjunctival sac for several hours. The ocular surface was washed carefully with distilled water. The opacity improved gradually over several months and scarring was replaced by secondary pterygium., Experiment: A button battery was placed on an eyeball of a pig, with the cathode directed toward the cornea. Corneal opacity developed in five minutes and increased thereafter. Another battery was sanded with saline-soaked gauze and the gauze near the cathode turned dark brown. This change intensified when the gauze was in contact with the side of the battery., Conclusions: The cornea and conjunctiva of the patient were damaged by continuous exposure to alkaline solution (concentrated NaOH) after the button battery had entered the lacrimal sac causing fixation by chemosis. The recent development of smaller batteries increases the risk of similar accidents. Button battery-induced burn injuries may be severe and require immediate correct diagnosis and treatment, especially in small children who may be difficult to examine.