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1.
Front Neurol ; 12: 675502, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33995266

RESUMO

Background: Cochlear implantation (CI) helps patients with severe or profound sensorineural hearing loss (SNHL) restore hearing and speech abilities. However, some patients exhibit abnormal vestibular functions with symptoms such as dizziness or balance disorders, after CI. Whether age at CI and CI approach (unilateral or sequential bilateral) affect vestibular functions in users with cochlear implants remains unclear. Objectives: To investigate the vestibular functions in children and adults before and after unilateral or sequential bilateral CI. Materials and Methods: Thirty-seven patients with severe or profound SNHL who were candidates for a first- or second-side CI were divided into three groups: first-side CI-implanted adults (≥18 years), first-side CI-implanted children (6-17 years), and second-side CI-implanted children (6-17 years). All cases were implanted with the round window approach to minimize damage to the intra-cochlear structures. The caloric test, vestibular evoked myogenic potential (VEMP) test, video head impulse test (vHIT), Dizziness Handicap Inventory (DHI), Pediatric Vestibular Symptom Questionnaire (PVSQ), and audiometric tests were performed before and 1 month after CI. Results: The abnormal rates of caloric test and VEMP test after CI in the first-side CI-implanted adults and children significantly increased compared with those before CI. The pre-implantation VEMP test showed significantly higher abnormal rates between first- and second-side CI-implanted children. No other significant differences of abnormal rates between first- and second-side CI-implanted children or between first-side CI-implanted adults and children were found. In second-side CI-implanted children, PVSQ scores significantly increased at day 3 post-implantation but decreased at day 30. Conclusion: CI has a negative effect on the results of caloric and VEMP tests, but not on vHIT, indicating that the otolith and low-frequency semicircular canal (SCC) are more vulnerable to damage from CI. The alterations of vestibular functions resulting from CI surgery may be independent of age at CI and CI approach (unilateral or sequential bilateral). Long-term impacts on the vestibular function from CI surgery, as well as the chronic electrical stimulation to the cochlea, are still to be investigated.

2.
PLoS One ; 12(11): e0188522, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29190278

RESUMO

Light of different wavelengths is essential for plant growth and development. Short-wavelength radiation such as UV can shift the composition of flavonoids, glucosinolates, and other plant metabolites responsible for enhanced defense against certain herbivorous insects. The intensity of light-induced, metabolite-based resistance is plant- and insect species-specific and depends on herbivore feeding guild and specialization. The increasing use of light-emitting diodes (LEDs) in horticultural plant production systems in protected environments enables the creation of tailor-made light scenarios for improved plant cultivation and induced defense against herbivorous insects. In this study, broccoli (Brassica oleracea var. italica) plants were grown in a climate chamber under broad spectra photosynthetic active radiation (PAR) and were additionally treated with the following narrow-bandwidth light generated with LEDs: UV-A (365 nm), violet (420 nm), blue (470 nm), or green (515 nm). We determined the influence of narrow-bandwidth light on broccoli plant growth, secondary plant metabolism (flavonol glycosides and glucosinolates), and plant-mediated light effects on the performance and behavior of the specialized cabbage aphid Brevicoryne brassicae. Green light increased plant height more than UV-A, violet, or blue LED treatments. Among flavonol glycosides, specific quercetin and kaempferol glycosides were increased under violet light. The concentration of 3-indolylmethyl glucosinolate in plants was increased by UV-A treatment. B. brassicae performance was not influenced by the different light qualities, but in host-choice tests, B. brassicae preferred previously blue-illuminated plants (but not UV-A-, violet-, or green-illuminated plants) over control plants.


Assuntos
Afídeos/fisiologia , Brassica/metabolismo , Raios Ultravioleta , Animais , Brassica/imunologia , Ácidos Cumáricos/metabolismo , Glucosinolatos/metabolismo , Interações Hospedeiro-Parasita , Indóis/metabolismo , Quempferóis/metabolismo , Folhas de Planta , Quercetina/metabolismo
3.
J Chem Ecol ; 42(10): 989-1003, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27589867

RESUMO

Light of different wavelengths affects various physiological processes in plants. Short-wavelength radiation (like UV) can activate defense pathways in plants and enhance the biosynthesis of secondary metabolites (such as flavonoids and glucosinolates) responsible for resistance against certain herbivorous insects. The intensity of light-induced, metabolite-based resistance is plant- and insect species-specific and depends on herbivore feeding guild and specialization. In this study, broccoli (Brassica oleracea var. italica) plants were grown for 4 weeks in a climate chamber under conventional fluorescent tubes and were additionally treated with UV-B (310 nm), UV-A (365 or 385 nm), or violet (420 nm) light generated with UV-B tubes or light-emitting diodes (LEDs). The objective was to determine the influence of narrow bandwidths of light (from UV-B to violet) on plant secondary metabolism and on the performance of the cabbage aphid Brevicoryne brassicae (a specialist) and the green peach aphid Myzus persicae (a generalist). Among flavonol glycosides, specific quercetin and kaempferol glycosides increased markedly under UV-B, while among glucosinolates only 4-methoxy-3-indolylmethyl showed a 2-fold increase in plants exposed to UV-B and UV-A. The concentration of 3-indolylmethyl glucosinolate in broccoli plants increased with UV-B treatment. Brevicoryne brassicae adult weights and fecundity were lower on UV-B treated plants compared to UV-A or violet light-treated plants. Adult weights and fecundity of M. persicae were increased under UV-B and UV-A treatments. When specific light wavelengths are used to induce metabolic changes in plants, the specificity of the induced effects on herbivores should be considered.


Assuntos
Afídeos/fisiologia , Brassica/fisiologia , Flavonoides/metabolismo , Glucosinolatos/metabolismo , Herbivoria , Animais , Luz , Processos Fotoquímicos , Metabolismo Secundário , Raios Ultravioleta
4.
Zhongguo Zhong Yao Za Zhi ; 39(5): 846-50, 2014 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-25204177

RESUMO

Twenty-one compounds were isolated from the rhizomes of Iris germanica by various chromatographic techniques such as silica gel, ODS and Sephadex LH-20 chromatography. Their structures were established on basis of physical properties, MS and NMR spectroscopic data Their structures were identified as ombuin (1), 5, 3, 3'-trihydroxy-7, 4'-dimethoxyflavanone (2), naringenin (3), cirsiliol-4'-glucoside (4), 3beta, 4'-dihydroxy-7,3'-dimethoxyflavonone-5-O-beta-D-glucopyranoside (5), genistein (6), irilin D (7), muningin (8), 5, 7, 4'-trihydroxy-6, 3', 5'-trimethoxyisoflavone (9), tectorigenin (10), irigenin (11), tectoridin (12), iridin (13), mangiferin (14), irisxanthone (15), pyroglutamic acid (16), 2, 4', 6-trihydroxy-4-methoxybenzophenone-2-O-beta-D-glucoside (17), apocynin (18), androsin (19), beta-sitosterol (20), and daucosterol (21). Among them, compounds 1-9, 16, 17 were obtained from this plant for the first time, compounds 8 and 9 were separated from Iris species for the first time, compounds 1, 4, and 17 were obtained from the family for the first time.


Assuntos
Medicamentos de Ervas Chinesas/química , Gênero Iris/química , Rizoma/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Estrutura Molecular , Espectrometria de Massas por Ionização por Electrospray
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