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81.
Ana Fakin Crystel Bonnet Anne Kurtenbach Saddek Mohand-Said Ditta Zobor Katarina Stingl Francesco Testa Francesca Simonelli Jos-Alain Sahel Isabelle Audo Eberhart Zrenner Marko Hawlina Christine Petit 《International journal of molecular sciences》2021,22(19)
In contrast to USH2A, variants in ADGRV1 are a minor cause of Usher syndrome type 2, and the associated phenotype is less known. The purpose of the study was to characterize the retinal phenotype of 18 ADGRV1 patients (9 male, 9 female; median age 52 years) and compare it with that of 204 USH2A patients (111 male, 93 female; median age 43 years) in terms of nyctalopia onset, best corrected visual acuity (BCVA), fundus autofluorescence (FAF), and optical coherence tomography (OCT) features. There was no statistical difference in the median age at onset (30 and 18 years; Mann–Whitney U test, p = 0.13); the mean age when 50% of the patients reached legal blindness (≥1.0 log MAR) based on visual acuity (64 years for both groups; log-rank, p = 0.3); the risk of developing advanced retinal degeneration (patch or atrophy) with age (multiple logistic regression, p = 0.8); or the frequency of cystoid macular edema (31% vs. 26%, Fisher’s exact test, p = 0.4). ADGRV1 and USH2A retinopathy were indistinguishable in all major functional and structural characteristics, suggesting that the loss of function of the corresponding proteins produces similar effects in the retina. The results are important for counseling ADGRV1 patients, who represent the minor patient subgroup. 相似文献
82.
Vasily Smirnov Olivier Grunewald Jean Muller Christina Zeitz Carolin D. Obermaier Aurore Devos Valrie Pelletier Batrice Bocquet Camille Andrieu Jean-Louis Bacquet Elodie Lebredonchel Saddek Mohand-Saïd Sabine Defoort-Dhellemmes Jos-Alain Sahel Hlne Dollfus Xavier Zanlonghi Isabelle Audo Isabelle Meunier Elise Boulanger-Scemama Claire-Marie Dhaenens 《International journal of molecular sciences》2021,22(12)
Variants of the TTLL5 gene, which encodes tubulin tyrosine ligase-like family member five, are a rare cause of cone dystrophy (COD) or cone-rod dystrophy (CORD). To date, only a few TTLL5 patients have been clinically and genetically described. In this study, we report five patients harbouring biallelic variants of TTLL5. Four adult patients presented either COD or CORD with onset in the late teenage years. The youngest patient had a phenotype of early onset severe retinal dystrophy (EOSRD). Genetic analysis was performed by targeted next generation sequencing of gene panels and assessment of copy number variants (CNV). We identified eight variants, of which six were novel, including two large multiexon deletions in patients with COD or CORD, while the EOSRD patient harboured the novel homozygous p.(Trp640*) variant and three distinct USH2A variants, which might explain the observed rod involvement. Our study highlights the role of TTLL5 in COD/CORD and the importance of large deletions. These findings suggest that COD or CORD patients lacking variants in known genes may harbour CNVs to be discovered in TTLL5, previously undetected by classical sequencing methods. In addition, variable phenotypes in TTLL5-associated patients might be due to the presence of additional gene defects. 相似文献
83.
Blandine Ponsard Isabelle Durot Philippe Delerive Fabien Oudot Catherine Cordelet Alain Grynberg Pierre Athias 《Lipids》1999,34(5):457-466
The purpose of the present investigation was to determine whether the beneficial effects of polyunsaturated fatty acids (PUFA)
may influence ischemia-reperfusion-induced alterations of myocardial α- and β-adrenoceptor (α-AR, β-AR) responsiveness. This
study was carried out using monolayer cultures of neonatal rat ventricular myocytes in a substrate-free, hypoxia-reoxygenation
model of ischemia. The cardiomyocytes (CM) were incubated during 4 days in media enriched either with n−6 PUFA (arachidonic
acid, AA) or with n−3 PUFA (eicosapentaenoic acid, EPA, and docosahexaenoic acid, DHA). The n−6/n−3 ratio in n−3 CM was close
to 1.2, compared to 20.1 in n−6 CM. The contractile parameters of n−6 CM and n−3 CM were similar in basal conditions as well
as during hypoxia and reoxygenation. In basal conditions, the phospholipid (PL) enrichment with long chain n−3 PUFA resulted
in an increased chronotropic response to isoproterenol (ISO) and to phenylephrine (PHE). After posthypoxic reoxygenation,
the chronotropic response to β-AR activation in n−6 CM was significantly enhanced as compared with the control response in
normoxia. In opposition, the ISO-induced rise in frequency in n−3 CM in control normoxia and after reoxygenation was similar.
In these n−3 CM, the changes in contractile parameters, which accompanied the chronotropic response, were also similar in
reoxygenation and in normoxic periods, although the rise in shortening velocity was slightly increased after reoxygenation.
In response to PHE addition, only the chronotropic effect of n−6 CM appeared significantly enhanced after hypoxic treatment.
These results suggested that increasing n−3 PUFA in PL reduced the increase in α- and β-AR functional responses observed after
hypoxia-reoxygenation. This effect may partly account for the assumed cardiac protective effect of n−3 PUFA, through the attenuation
of the functional response to catecholamines in the ischemic myocardium. 相似文献
84.
Processes affecting fish populations range in scale from local to global. Fish response is also scale‐dependent, with some activities varying locally while others depend on large‐scale connectivity within or between watersheds. These issues are still only partly recognized, with large‐scale research often affected by non‐independent sampling, weak inference, poor model testing or model over‐extrapolation. Available multi‐scale studies can reach different conclusions about factors affecting fishes from local studies, but results vary between examples. Potential explanations are (i) effects on fishes are context‐dependent; (ii) different species or life‐stages are limited in different ways; (iii) multi‐scale studies are too few for generalization. We advocate improved use of geostatistical tools to guide sampling or interpret the spatial extent of management problems, and we illustrate this using brown trout in Welsh streams. Our strongest recommendation is that fish ecologists recognize the importance of interactions across scales in quantifying effects on fishes so that management decisions can be better based on evidence rather than judgement or extrapolation. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
85.
The surface of wooden shelves used in the ripening of a raw milk smear cheese was examined by attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy. FTIR spectra of zones of wooden shelves in contact with cheeses or not (control) were acquired. This acquisition was performed either directly after cheeses removal or after brushing with water to remove cheese compounds deposited onto wood surfaces. Their analysis revealed that the degree of similarity between the ATR-FTIR spectra of unused and cleaned by brushing wooden shelves is higher than with the spectra of non-cleaned surfaces. The spectra of non-cleaned zones where cheeses were ripened namely differed in the 920–1180 cm?1 and in the 1485–1780 cm?1 regions. These regions can be assigned to proteins and polysaccharides and thus might correspond to deposits of cheese rind surface as well as to the presence of microbial biofilms on wooden shelves. Similarities in these spectral regions with those of cheese rind support this hypothesis. These observations indicate that ATR-FTIR spectroscopy is a rapid and valuable analytical tool to directly investigate the global chemical composition of very thin films such as microbial biofilms or cheese rind deposits present on wooden shelves which are not accessible to standard chemical methods. 相似文献
86.
Ming Liu Sandrine Zanna Isabelle Frateur Guangling Song Philippe Marcus 《Corrosion Science》2009,51(5):1115-191
An XPS investigation was carried out of the surface films, formed by exposure to ultrapure water, on mechanically ground Mg and the two Mg-Al intermetallic compounds: Al3Mg2 and Mg17Al12. The mechanically ground Mg surface had a film of MgO at the Mg metal surface covered by a Mg(OH)2 layer, formed by the reaction of the MgO with water vapour in the air. Upon immersion in ultrapure water, this film converted to a duplex film with an inner MgO layer next to the Mg metal and an external porous hydroxide layer. For both intermetallics, the XPS data is consistent with (i) preferential dissolution of Mg and (ii) a 10 nm thick film on the surface after immersion in ultrapure water; the film composition on Al3Mg2 was AlMg1.4O0.2(OH)5.4 whilst on Mg17Al12 the composition was AlMg2.5(OH)8. 相似文献
87.
Aly Farag El Sheikha Ana Condur Isabelle Métayer Doan Duy Le Nguyen Gérard Loiseau Didier Montet 《Yeast (Chichester, England)》2009,26(10):567-573
The determination of geographical origin is a demand of the traceability system of import–export food products. One hypothesis for tracing the source of a product is by global analysis of the microbial communities of the food and statistical linkage of this analysis to the geographical origin of the food. For this purpose, a molecular technique employing 26S rDNA profiles generated by PCR–DGGE was used to detect the variation in yeast community structures of three species of Physalis fruit (Physalis ixocarpa Brat, Physalis pubescens L, Physalis pruinosa L) from four Egyptian regions (Qalyoubia, Minufiya, Beheira and Alexandria Governments). When the 26S rDNA profiles were analysed by multivariate analysis, distinct microbial communities were detected. The band profiles of Physalis yeasts from different Governments were specific for each location and could be used as a bar code to discriminate the origin of the fruits. This method is a new traceability tool which provides fruit products with a unique biological bar code and makes it possible to trace back the fruits to their original location. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
88.
89.
90.
Mia Isabelle Bee Lan Lee Meng Thiam Lim Woon-Puay Koh Dejian Huang Choon Nam Ong 《Food chemistry》2010
Sixty-six types of vegetables commonly consumed in Singapore were analysed for their hydrophilic oxygen radical absorbance capacity (H-ORAC), total phenolic content (TPC), ascorbic acid (AA) and various lipophilic antioxidants. A single batch analysis of each vegetable showed that antioxidant composition and concentration varied widely across different vegetables. The vegetables with intense colours typically have high H-ORAC, TPC, AA, and carotenoid contents. Vegetables unique to the Asian market such as matrimony vine (Lycium chinense Miller), coriander, Chinese kale, water spinach and red chilli were consistently ranked high in H-ORAC, TPC, carotenoids and vitamin E levels. Based on consumption data, Chinese Singaporeans appear to have a higher intake of lutein, zeaxanthin, β-carotene, and tocopherols compared to the US population. Overall findings suggest that dark green leafy and brightly-coloured vegetables tend to contain high antioxidants. Our data are useful reference and substantiate many public health agencies’ recommendation to consume more vegetables, particularly the dark green leafy and brightly-coloured varieties. 相似文献