排序方式: 共有9条查询结果,搜索用时 15 毫秒
1
1.
Adults of the human parasitic trematode Schistosoma mansoni, which causes
hepatosplenic/intestinal complications in humans, synthesize
glycoconjugates containing the Lewis x (Lex) Galbeta1-->4(Fucalpha1--
>3)GlcNAcbeta1-->R, but not sialyl Lewis x (sLex), antigen. We now
report on our analyses of Lexand sLexexpression in S.haematobium and
S.japonicum, which are two other major species of human schistosomes that
cause disease, and the possible autoimmunity to these antigens in infected
individuals. Antigen expression was evaluated by both ELISA and Western
blot analyses of detergent extracts of parasites using monoclonal
antibodies. Several high molecular weight glycoproteins in both S.
haematobium and S. japonicum contain the Lexantigen, but no sialyl
Lexantigen was detected. In addition, sera from humans and rodents infected
with S.haematobium and S.japonicum contain antibodies reactive with Lex.
These results led us to investigate whether Lexantigens are expressed in
other helminths, including the parasitic trematode Fasciola hepatica , the
parasitic nematode Dirofilaria immitis (dog heartworm), the ruminant
nematode Haemonchus contortus , and the free-living nematode Caenorhabditis
elegans . Neither Lexnor sialyl-Lexis detectable in these other helminths.
Furthermore, none of the helminths, including schistosomes, express Lea,
Leb, Ley, or the H- type 1 antigen. However, several glycoproteins from all
helminths analyzed are bound by Lotus tetragonolobus agglutinin , which
binds Fucalpha1-->3GlcNAc, and Wisteria floribunda agglutinin, which
binds GalNAcbeta1-->4GlcNAc (lacdiNAc or LDN). Thus, schistosomes may be
unique among helminths in expressing the Lexantigen, whereas many different
helminths may express alpha1,3-fucosylated glycans and the LDN motif.
相似文献
2.
A new cell line has been established from larval hemocytes of the moth, S. litura (tobacco cut worm). It took 147 days to form a monolayer and one year for the first 17 passages. At present, the culture is at 86th passage level and is designated NIV-SU-1095. Three cell types could be distinguished, viz. plasmatocytes (53%), prohemocytes (36%) and granular hemocytes (11%). The chromosome number was very high, 74% metaphase cells showed more than 100 chromosomes. The cells could be cryopreserved. The cells were susceptible to the baculoviruses, Autographa californica nuclear polyhedrosis virus and S. litura nuclear polyhedrosis virus (SLNPV). Plaques could be observed on 7th post infection day with SLNPV. Six cloned cell lines have been developed of which clone II-1F was more sensitive to both the baculoviruses compared to the original cell line. 相似文献
3.
Maxim VC Greenberg Israel Ausin Simon WL Chan Shawn J Cokus Josh T Cuperus Suhua Feng Julie A Law Carolyn Chu Matteo Pellegrini James C Carrington Steven E Jacobsen 《Epigenetics》2011,6(3):344-354
De novo DNA methylation in Arabidopsis thaliana is catalyzed by the methyltransferase DRM2, a homolog of the mammalian de novo methyltransferase DNMT3. DRM2 is targeted to DNA by small interfering RNAs (siRNAs) in a process known as RNA-directed DNA Methylation (RdDM). While several components of the RdDM pathway are known, a functional understanding of the underlying mechanism is far from complete. We employed both forward and reverse genetic approaches to identify factors involved in de novo methylation. We utilized the FWA transgene, which is methylated and silenced when transformed into wild-type plants, but unmethylated and expressed when transformed into de novo methylation mutants. Expression of FWA is marked by a late-flowering phenotype, which is easily scored in mutant versus wild-type plants. By reverse genetics we discovered the requirement for known RdDM effectors AGO6 and NRPE5a for efficient de novo methylation. A forward genetic approach uncovered alleles of several components of the RdDM pathway, including alleles of clsy1, ktf1 and nrpd/e2, which have not been previously shown to be required for the initial establishment of DNA methylation. Mutations were mapped and genes cloned by both traditional and whole genome sequencing approaches. The methodologies and the mutant alleles discovered will be instrumental in further studies of de novo DNA methylation.Key words: DNA methylation, Arabidopsis, de novo, genetic screen, whole-genome sequencing 相似文献
4.
Performance of monolayered cervical smears in a gynecology outpatient setting in Kuwait 总被引:6,自引:0,他引:6
Luthra UK Chishti M Dey P Jolly SV Abdulla M Das DK Sugathan TN Ajrawi MT George J George SS Aziz AA al-Juwaiser A Karim FA Mallik MK Sheikh ZA Khan S 《Acta cytologica》2002,46(2):303-310
OBJECTIVE: To compare ThinPrep (TP) Papanicolaou smears (Cytyc Corp., Box-borough, Massachusetts, U.S.A.) with matching conventional Papanicolaou (CP) smears for specimen adequacy, cytologic quality, diagnostic accuracy and screening time. STUDY DESIGN: In this prospective study of 1,024 women a split-sample, matched-pair design in favor of CP slides based on single-blind criteria was followed with a smear on a glass slide for CP and the remaining material collected in Preserv-Cyt solution (Cytyc) for a TP smear. A Cytobrush (Medscand, Hollywood, Florida, U.S.A.) was used for smear preparation for CP. TP smears were processed in ThinPrep 2000 (Cytyc). Smears were stained with Papanicolaou stain and were interpreted according to the Bethesda system. RESULTS: The number of satisfactory but limited (SBL) cases with TP were 77 (7.5%) as compared to 127 (12.4%) with the CP method. This reduction in SBL smears with the TP method and consequent increase in satisfactory smears were highly significant (P < .001) by McNemar's test. As regards unsatisfactory smears in discordant pairs, although the number of unsatisfactory smears was higher with TP (41 cases) as against CP (27 cases), the difference was not statistically significant (P < .05). The split-sample method showed a high correlation between the CP and TP diagnoses. TP smears had a significant advantage over CP smears in the reduction in the number of ASCUS and AGUS cases (14 vs. 29) (P < .05) and increased the pickup rate of LSIL, 6 vs. 1. Time taken to screen the TP smears was half that of CP smears. No cases of LSIL or HSIL were missed on TP smears. CONCLUSION: The liquid-based processor significantly improved the adequacy and quality of smears, resulting in fewer recall cases for SBL smears, leading to more definitive diagnoses in atypical cases, increasing the pickup rate of LSILs and reducing the screening time. A machine handling multiple specimens automatically would decrease cost and be an asset to a cytopathology laboratory. 相似文献
5.
6.
Lotte Heimans Kirsten VC Wevers-de Boer KK Michel Koudijs Karen Visser Yvonne P Goekoop-Ruiterman Joop B Harbers Gerda M Steup-Beekman Leroy R Lard Bernard AM Grillet Tom WJ Huizinga Cornelia F Allaart 《Arthritis research & therapy》2013,15(5):R173
Introduction
The aim of this study was to investigate patient reported outcomes (PROs) of functional ability and health related quality of life (HRQoL) in patients with early (rheumatoid) arthritis during one year of remission steered treatment.Methods
In this study, 610 patients with early rheumatoid arthritis (RA) or undifferentiated arthritis (UA) were treated with methotrexate (MTX) and tapered high dose of prednisone. Patients in early remission (Disease Activity Score (DAS) <1.6 after 4 months) tapered prednisone to zero and when in persistent remission, also tapered MTX. Patients not in early remission were randomized to either MTX + hydroxychloroquine + sulphasalazine + prednisone (arm 1) or to MTX + adalimumab (arm 2). Every 4 months, patients filled out the Health Assessment Questionnaire (HAQ) and the McMaster Toronto Arthritis Patient Preference Questionnaire (MACTAR), the Short Form 36 (SF-36) and visual analogue scales (VAS). Change scores were compared between treatment groups. The association with achieving remission was analyzed using linear mixed models.Results
During year 1, patients who achieved early remission had the most improvement in PROs with scores comparable to the general population. Patients in the randomization arms showed less improvement. Scores were comparable between the arms. There was a significant association between achieving remission and scores of HAQ, MACTAR and physical HRQoL.Conclusions
In early arthritis, PROs of functional ability and HRQoL after one year of remission steered treatment reach normal values in patients who achieved early remission. In patients not in early remission, who were randomized to two strategy arms, PROs improved less, with similar scores in both treatment arms.Trial registrations
ISRCTN11916566 and EudraCT2006-006186-16 相似文献7.
Núbia Boechat Alcione S Carvalho Kelly Salom?o Solange L de Castro Carlos F Araujo-Lima Francisco VC Mello Israel Felzenszwalb Claudia AF Aiub Taline Ramos Conde Helena PS Zamith Rolf Skupin Günter Haufe 《Memórias do Instituto Oswaldo Cruz》2015,110(4):492-499
Nitroimidazoles exhibit high microbicidal activity, but mutagenic, genotoxic and
cytotoxic properties have been attributed to the presence of the nitro group.
However, we synthesised nitroimidazoles with activity against the trypomastigotes of
Trypanosoma cruzi, but that were not genotoxic. Herein,
nitroimidazoles (11-19) bearing different substituent groups were investigated for
their potential induction of genotoxicity (comet assay) and mutagenicity
(Salmonella/Microsome assay) and the correlations of these
effects with their trypanocidal effect and with megazol were investigated. The
compounds were designed to analyse the role played by the position of the nitro group
in the imidazole nucleus (C-4 or C-5) and the presence of oxidisable
groups at N-1 as an anion receptor group and the role of a methyl group at C-2.
Nitroimidazoles bearing NO2 at C-4 and CH3 at C-2 were not genotoxic compared to
those bearing NO2 at C-5. However, when there was a CH3
at C-2, the position of the NO2 group had no influence on the genotoxic activity.
Fluorinated compounds exhibited higher genotoxicity regardless of the presence of CH3
at C-2 or NO2 at C-4 or C-5. However, in compounds 11 (2-CH3; 4-NO2; N-CH2OHCH2Cl)
and 12 (2-CH3; 4-NO2; N-CH2OHCH2F), the fluorine atom had no influence on
genotoxicity. This study contributes to the future search for new and safer
prototypes and provide. 相似文献
8.
Eight lepidopteran cell lines were established recently and their susceptibility to different insect viruses was studied. Two Spodoptera litura cell lines from the larval and pupal ovaries, were found highly susceptible to S. litura nuclear polyhedrosis virus (SLNPV, 5-6 x 10(6) NPV/ml). The Helicoverpa armigera cell line from the embryonic tissue was highly susceptible to H. armigera NPV (HaNPV, 6.3 x 10(6) NPV/ml). These in vitro grown SLNPV and HaNPV caused 100% mortality to respective 2nd instar larvae. The susceptibility of the cryo-preserved cell lines to respective baculoviruses (SLNPV/HaNPV) was studied and no significant difference in their susceptibility status was observed. The cultures could grow as suspension culture on shakers and may find application for in vitro production of wild type/recombinant baculoviruses as bio-insecticides. S. litura and Bombyx mori cell lines from larval ovaries, were highly susceptible to Autographa californica NPV (5.5 x 10(6) NPV/ml) and Bombyx mori NPV (BmNPV, 6.1 x 10(6) NPV/ml) respectively. These cell lines may find application in baculovirus expression vector studies for the production of recombinant proteins, useful in the development of diagnostic kits or as vaccines. 相似文献
9.
ABSTRACT: BACKGROUND: The Non-Structural (NS1) protein of Influenza A viruses is an extensively studied multifunctional protein which is commonly considered as key viral component to fight against host immune responses. Even though there has been a lot of studies on the involvement of NS1 protein in host immune responses there are still ambiguities regarding its role in apoptosis in infected cells. Interactions of NS1 protein with host factors, role of NS1 protein in regulating cellular responses and apoptosis are quiet complicated and further studies are still needed to understand it completely. RESULTS: NS1 genes of influenza A/Chicken/India/WBNIV2664/2008 (H5N1) and A/Aquatic bird/India/NIV-17095/2007(H11N1) were cloned and expressed in Human embryonic kidney (293T) cells. Microarray based approach to study the host cellular responses to NS1 protein of the two influenza A viruses of different pathogenicity showed significant differences in the host gene expression profile. NS1 protein of H5N1 resulted in suppression of IFN-beta mediated innate immune responses in 293T cells, leading to down-regulation of the components of JAK-STAT pathway like STAT1 which further suppressed the expression of pro-inflammatory cytokines like CXCL10 and CCL5. The degree of suppression of host immune genes was found considerable with NS1 protein of H11N1 but was not as prominent as with H5N1-NS1. TUNEL assay analyses were found to be positive in both the NS1 transfected cells indicating both H5N1 as well as H11N1 NS1 proteins were able to induce apoptosis in transfected cells. CONCLUSIONS: We propose that NS1 protein of both H5N1 and H11N1 subtypes of influenza viruses are capable of influencing host immune responses and possess necessary functionality to support apoptosis in host cells. H11N1, a low pathogenic virus without any proven evidence to infect mammals, contains a highly potential NS1 gene which might contribute to greater virus virulence in different gene combinations. 相似文献
1