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31.
Electron-nuclear double resonance (ENDOR) signals from matrix protons interacting with the stable free radicals of "A"- and "B"-type melanins have been observed as a function of pH. In all samples the single line is similar in width and unusually narrow. The ENDOR reduction varies by more than a factor of 10, indicating a large sensitivity of relaxation properties of melanin to sample type. Signals were observed over a wide range of experimental conditions with good signal-to-noise ratio, establishing feasibility for further more detailed ENDOR studies. Incubation in D2O resulted in little change, indicating that the free radical is well buried or protected. No resolved hyperfine structure was seen, consistent with the generally accepted view that melanin is a heterogeneous polymer. 相似文献
32.
Improved histological localization of GABA-transaminase activity in rat cerebellar cortex after aldehyde fixation 总被引:1,自引:0,他引:1
Summary A method for the chemical fixation of the enzyme GABA-transaminase in nervous tissue is described. It is shown that after
perfusion with a formaldehyde/glutaraldehyde fixative, activity of the enzyme in cerebellar cortex is demonstrable whilst
cellular morphology is preserved. Results from the improved technique have shown new sites of GABA-transaminase activity in
cerebellar cortex. In view of these results a special function for glial cells in this area of brain has been suggested. 相似文献
33.
34.
David F Ten Cate Jolanda J Luime Nanno Swen Andreas H Gerards Mike H De Jager Natalja M Basoski Johanna MW Hazes Cees J Haagsma Johannes WG Jacobs 《Arthritis research & therapy》2013,15(1):R4
Introduction
Ultrasonography (US) might have an added value to clinical examination in diagnosing early rheumatoid arthritis (RA) and assessing remission of RA. We aimed to clarify the added value of US in RA in these situations performing a systematic review.Methods
A systematic literature search was performed for RA, US, diagnosis and remission. Methodological quality was assessed; the wide variability in the design of studies prohibited pooling of results.Results
Six papers on the added value of US diagnosing early RA were found, in which at least bilateral metacarpophalangeal (MCP), wrists and metatarsophalangeal (MTP) joints were scanned. Compared to clinical examination, US was superior with regard to detecting synovitis and predicting progression to persistent arthritis or RA. Eleven papers on assessing remission were identified, in which at least the wrist and the MCP joints of the dominant hand were scanned. Often US detected inflammation in patients clinically in remission, irrespective of the remission criteria used. Power Doppler signs of synovitis predicted X-ray progression and future flare in patients clinically in remission.Conclusions
US appears to have added value to clinical examination for diagnosing of RA when scanning at least MCP, wrist and MTP joints, and, when evaluating remission of RA, scanning at least wrist and MCP joints of the dominant hand. For both purposes primarily power Doppler US might be used since its results are less equivocal than those of greyscale US. 相似文献35.
Larissa N. Vasilyeva Aleksey V. Chernyshev Steven L. Stevenson Kevin D. Hyde 《Mycoscience》2013,54(2):110-115
Two new species collected in northern Thailand are herein described and discussed. Tortulomyces thailandicus is the type of a new genus characterized by a combination of such features as a dense subiculum, non-ostiolate ascomata, two kinds of paraphyses (filiform and bead-like), and 1-septate, brown ascospores. Nitschkia siamensis has non-ostiolate, turbinate and stalked ascomata and hyaline, often slightly curved, 1-septate ascospores. 相似文献
36.
Nakarin Suwannarach Jaturong Kumla Boonsom Bussaban Kevin D. Hyde Kenji Matsui Saisamorn Lumyong 《Annals of microbiology》2013,63(4):1341-1351
The genus Muscodor comprises fungal endophytes which produce mixtures of volatile compounds (VOCs) with antimicrobial activities. In the present study, four novel species, Muscodor musae, M. oryzae, M. suthepensis and M. equiseti were isolated from Musa acuminata, Oryza rufipogon, Cinnamomum bejolghota and Equisetum debile, respectively; these are medicinal plants of northern Thailand. The new Muscodor species are distinguished based on morphological and physiological characteristics and on molecular analysis of ITS-rDNA. Volatile compound analysis showed that 2-methylpropanoic acid was the main VOCs produced by M. musae, M. suthepensis and M. equiseti. The mixed volatiles from each fungus showed in vitro antimicrobial activity. Muscodor suthepensis had the highest antifungal activity. 相似文献
37.
Amit A. Negandhi Angela Hyde Elizabeth Dicks William Pollett Banfield H. Younghusband Patrick Parfrey Roger C. Green Sevtap Savas 《PloS one》2013,8(4)
Introduction
In this study, 27 genetic polymorphisms that were previously reported to be associated with clinical outcomes in colorectal cancer patients were investigated in relation to overall survival (OS) and disease free survival (DFS) in colorectal cancer patients from Newfoundland.Methods
The discovery and validation cohorts comprised of 532 and 252 patients, respectively. Genotypes of 27 polymorphisms were first obtained in the discovery cohort and survival analyses were performed assuming the co-dominant genetic model. Polymorphisms associated with disease outcomes in the discovery cohort were then investigated in the validation cohort.Results
When adjusted for sex, age, tumor stage and microsatellite instability (MSI) status, four polymorphisms were independent predictors of OS in the discovery cohort MTHFR Glu429Ala (HR: 1.72, 95%CI: 1.04–2.84, p = 0.036), ERCC5 His46His (HR: 1.78, 95%CI: 1.15–2.76, p = 0.01), SERPINE1 −675indelG (HR: 0.52, 95%CI: 0.32–0.84, p = 0.008), and the homozygous deletion of GSTM1 gene (HR: 1.4, 95%CI: 1.03–1.92, p = 0.033). In the validation cohort, the MTHFR Glu429Ala polymorphism was associated with shorter OS (HR: 1.71, 95%CI: 1.18–2.49, p = 0.005), although with a different genotype than the discovery cohort (CC genotype in the discovery cohort and AC genotype in the validation cohort). When stratified based on treatment with 5-Fluorouracil (5-FU)-based regimens, this polymorphism was associated with reduced OS only in patients not treated with 5-FU. In the DFS analysis, when adjusted for other variables, the TT genotype of the ERCC5 His46His polymorphism was associated with shorter DFS in both cohorts (discovery cohort: HR: 1.54, 95%CI: 1.04–2.29, p = 0.032 and replication cohort: HR: 1.81, 95%CI: 1.11–2.94, p = 0.018).Conclusions
In this study, associations of the MTHFR Glu429Ala polymorphism with OS and the ERCC5 His46His polymorphism with DFS were identified in two colorectal cancer patient cohorts. Our results also suggest that the MTHFR Glu429Ala polymorphism may be an adverse prognostic marker in patients not treated with 5-FU. 相似文献38.
39.
Jie Chen Magalie Moinard Jianping Xu Shouxian Wang Marie Foulongne-Oriol Ruilin Zhao Kevin D. Hyde Philippe Callac 《PloS one》2016,11(5)
The internal transcribed spacer (ITS) region of the nuclear ribosomal RNA gene cluster is widely used in fungal taxonomy and phylogeographic studies. The medicinal and edible mushroom Agaricus subrufescens has a worldwide distribution with a high level of polymorphism in the ITS region. A previous analysis suggested notable ITS sequence heterogeneity within the wild French isolate CA487. The objective of this study was to investigate the pattern and potential mechanism of ITS sequence heterogeneity within this strain. Using PCR, cloning, and sequencing, we identified three types of ITS sequences, A, B, and C with a balanced distribution, which differed from each other at 13 polymorphic positions. The phylogenetic comparisons with samples from different continents revealed that the type C sequence was similar to those found in Oceanian and Asian specimens of A. subrufescens while types A and B sequences were close to those found in the Americas or in Europe. We further investigated the inheritance of these three ITS sequence types by analyzing their distribution among single-spore isolates from CA487. In this analysis, three co-dominant markers were used firstly to distinguish the homokaryotic offspring from the heterokaryotic offspring. The homokaryotic offspring were then analyzed for their ITS types. Our genetic analyses revealed that types A and B were two alleles segregating at one locus ITSI, while type C was not allelic with types A and B but was located at another unlinked locus ITSII. Furthermore, type C was present in only one of the two constitutive haploid nuclei (n) of the heterokaryotic (n+n) parent CA487. These data suggest that there was a relatively recent introduction of the type C sequence and a duplication of the ITS locus in this strain. Whether other genes were also transferred and duplicated and their impacts on genome structure and stability remain to be investigated. 相似文献
40.
Eleanor Burnett Tenneth Dalipanda Divi Ogaoga Jenny Gaiofa Gregory Jilini Alison Halpin Vance Dietz Kashmira Date Eric Mintz Terri Hyde Kathleen Wannemuehler Catherine Yen 《PLoS neglected tropical diseases》2016,10(8)
BackgroundIn response to a 2011 cholera outbreak in Papua New Guinea, the Government of the Solomon Islands initiated a cholera prevention program which included cholera disease prevention and treatment messaging, community meetings, and a pre-emptive cholera vaccination campaign targeting 11,000 children aged 1–15 years in selected communities in Choiseul and Western Provinces.ConclusionsThis pre-emptive OCV campaign in a cholera-naïve community provided a unique opportunity to assess household-level knowledge, attitudes, and practices regarding diarrhea, cholera, and water, sanitation, and hygiene (WASH). Our findings suggest that education provided during the vaccination campaign may have reinforced earlier mass messaging about cholera and diarrheal disease in vaccinated communities. 相似文献