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151.
Pomajbíková K Petrželková KJ Petrášová J Profousová I Kalousová B Jirků M Sá RM Modrý D 《The Journal of eukaryotic microbiology》2012,59(1):97-99
Trophozoites of Troglocorys cava were detected in all but one of the wild chimpanzee populations from Rubondo Island (Tanzania), with a prevalence ranging between 20% and 78%. However, the ciliate was absent in all captive groups. Prevalence appeared to increase with the number of sequential samples taken from a particular individual and reached 95.5% in wild individuals sampled at least 4 times. 相似文献
152.
Alquicer G Sedlák D Byun Y Pavlícek J Stathis M Rojas C Slusher B Pomper MG Bartunek P Barinka C 《Journal of biomolecular screening》2012,17(8):1030-1040
Glutamate carboxypeptidase II (GCPII) is an important target for therapeutic and diagnostic interventions aimed at prostate cancer and neurologic disorders. Here we describe the development and optimization of a high-throughput screening (HTS) assay based on fluorescence polarization (FP) that facilitates the identification of novel scaffolds inhibiting GCPII. First, we designed and synthesized a fluorescence probe based on a urea-based inhibitory scaffold covalently linked to a Bodipy TMR fluorophore (TMRGlu). Next, we established and optimized conditions suitable for HTS and evaluated the assay robustness by testing the influence of a variety of physicochemical parameters (e.g., pH, temperature, time) and additives. Using known GCPII inhibitors, the FP assay was shown to be comparable to benchmark assays established in the field. Finally, we evaluated the FP assay by HTS of a 20 000-compound library. The novel assay presented here is robust, highly reproducible (Z' = 0.82), inexpensive, and suitable for automation, thus providing an excellent platform for HTS of small-molecule libraries targeting GCPII. 相似文献
153.
Cyntia Anabel Amorosi Helena Myskóva Mariela Roxana Monti Carlos Enrique Argara?a Masashi Morita Stephan Kemp Raquel Dodelson de Kremer Lenka Dvoráková Ana María Oller de Ramírez 《PloS one》2012,7(12)
X-linked adrenoleukodystrophy (X-ALD) is an inherited metabolic disease associated with mutations in the ABCD1 gene that encodes an ATP-binding cassette transporter protein, ALDP. The disease is characterized by increased concentrations of very long-chain fatty acids (VLCFAs) in plasma and in adrenal, testicular and nervous tissues, due to a defect in peroxisomal VLCFA β-oxidation. In the present study, we analyzed 10 male patients and 17 female carriers from 10 unrelated pedigrees with X-ALD from Argentina. By sequencing the ABCD1 we detected 9 different mutations, 8 of which were novel. These new mutations were verified by a combination of methods that included both functional (western blot and peroxisomal VLCFA β-oxidation) and bioinformatics analysis. The spectrum of novel mutations consists of 3 frameshift (p.Ser284fs*16, p.Glu380Argfs*21 and p.Thr254Argfs*82); a deletion (p.Ser572_Asp575del); a splicing mutation (c.1081+5G>C) and 3 missense mutations (p.Ala341Asp, p.His420Pro and p.Tyr547Cys). In one patient 2 changes were found: a known missense (p.His669Arg) and an unpublished amino acid substitution (p.Ala19Ser). In vitro studies suggest that p.Ala19Ser is a polymorphism. Moreover, we identified two novel intronic polymorphisms and two amino acid polymorphisms. In conclusion, this study extends the spectrum of mutation in X-ALD and facilitates the identification of heterozygous females. 相似文献
154.
Karthick Raja Muthu Raja Lucie Rihova Lenka Zahradova Maria Klincova Miroslav Penka Roman Hajek 《PloS one》2012,7(10)
Background
Regulatory T (Treg) cells play an important role in the maintenance of immune system homeostasis. Multiple myeloma (MM) is a plasma cell disorder frequently associated with impaired immune cell numbers and functions.Methods
We analyzed Treg cells in peripheral blood (n = 207) and bone marrow (n = 202) of pre-malignant and malignant MM patients using flow cytometry. Treg cells and their subsets from MM patients and healthy volunteers were functionally evaluated for their suppressive property. A cohort of 25 patients was analyzed for lymphocytes, CD4 T cells and Treg cells before and after treatment with cyclophosphamide, thalidomide plus dexamethasone (CTD).Results
We found elevated frequencies of Treg cells in newly diagnosed (P<0.01) and relapsed MM patients (P<0.0001) compared to healthy volunteers. Also, Treg subsets including naïve (P = 0.015) and activated (P = 0.036) Treg cells were significantly increased in MM patients compared to healthy volunteers. Functional studies showed that Treg cells and their subsets from both MM and healthy volunteers were similar in their inhibitory function. Significantly increased frequencies of Treg cells were found in MM patients with adverse clinical features such as hypercalcemia (>10 mg/dL), decreased normal plasma cell (≤5%) count and IgA myeloma subtype. We also showed that MM patients with ≥5% of Treg cells had inferior time to progression (TTP) (13 months vs. median not reached; P = 0.013). Furthermore, we demonstrated the prognostic value of Treg cells in prediction of TTP by Cox regression analysis (P = 0.045). CTD treatment significantly reduced frequencies of CD4 T cells (P = 0.001) and Treg cells (P = 0.018) but not Treg cells/CD4 T cells ratio compared to pre-treatment.Conclusions
Our study showed immune deregulation in MM patients which is evidenced by elevated level of functionally active Treg cells and patients with increased Treg cells have higher risk of progression. 相似文献155.
Pavlina Sobrova Lenka Vyslouzilova Olga Stepankova Marketa Ryvolova Jiri Anyz Libuse Trnkova Vojtech Adam Jaromir Hubalek Rene Kizek 《PloS one》2012,7(11)
Background
Proteomics and metalloproteomics are rapidly developing interdisciplinary fields providing enormous amounts of data to be classified, evaluated and interpreted. Approaches offered by bioinformatics and also by biostatistical data analysis and treatment are therefore of extreme interest. Numerous methods are now available as commercial or open source tools for data processing and modelling ready to support the analysis of various datasets. The analysis of scientific data remains a big challenge, because each new task sets its specific requirements and constraints that call for the design of a targeted data pre-processing approach.Methodology/Principal Findings
This study proposes a mathematical approach for evaluating and classifying datasets obtained by electrochemical analysis of metallothionein in rat 9 tissues (brain, heart, kidney, eye, spleen, gonad, blood, liver and femoral muscle). Tissue extracts were heated and then analysed using the differential pulse voltammetry Brdicka reaction. The voltammograms were subsequently processed. Classification models were designed making separate use of two groups of attributes, namely attributes describing local extremes, and derived attributes resulting from the level = 5 wavelet transform.Conclusions/Significance
On the basis of our results, we were able to construct a decision tree that makes it possible to distinguish among electrochemical analysis data resulting from measurements of all the considered tissues. In other words, we found a way to classify an unknown rat tissue based on electrochemical analysis of the metallothionein in this tissue. 相似文献156.
157.
158.
Radovan Fiser Jiri Masin Ladislav Bumba Eva Pospisilova Catherine Fayolle Marek Basler Lenka Sadilkova Irena Adkins Jana Kamanova Jan Cerny Ivo Konopasek Radim Osicka Claude Leclerc Peter Sebo 《PLoS pathogens》2012,8(4)
Bordetella adenylate cyclase toxin-hemolysin (CyaA) penetrates the cytoplasmic membrane of phagocytes and employs two distinct conformers to exert its multiple activities. One conformer forms cation-selective pores that permeabilize phagocyte membrane for efflux of cytosolic potassium. The other conformer conducts extracellular calcium ions across cytoplasmic membrane of cells, relocates into lipid rafts, translocates the adenylate cyclase enzyme (AC) domain into cells and converts cytosolic ATP to cAMP. We show that the calcium-conducting activity of CyaA controls the path and kinetics of endocytic removal of toxin pores from phagocyte membrane. The enzymatically inactive but calcium-conducting CyaA-AC− toxoid was endocytosed via a clathrin-dependent pathway. In contrast, a doubly mutated (E570K+E581P) toxoid, unable to conduct Ca2+ into cells, was rapidly internalized by membrane macropinocytosis, unless rescued by Ca2+ influx promoted in trans by ionomycin or intact toxoid. Moreover, a fully pore-forming CyaA-ΔAC hemolysin failed to permeabilize phagocytes, unless endocytic removal of its pores from cell membrane was decelerated through Ca2+ influx promoted by molecules locked in a Ca2+-conducting conformation by the 3D1 antibody. Inhibition of endocytosis also enabled the native B. pertussis-produced CyaA to induce lysis of J774A.1 macrophages at concentrations starting from 100 ng/ml. Hence, by mediating calcium influx into cells, the translocating conformer of CyaA controls the removal of bystander toxin pores from phagocyte membrane. This triggers a positive feedback loop of exacerbated cell permeabilization, where the efflux of cellular potassium yields further decreased toxin pore removal from cell membrane and this further enhances cell permeabilization and potassium efflux. 相似文献
159.
Gabriele Volpato Pavlína Kourková Václav Zelený 《Journal of ethnobiology and ethnomedicine》2012,8(1):49
Background
Over the past decade, there has been growing interest within ethnobiology in the knowledge and practices of migrating people. Within this, scholars have given relatively less attention to displaced people and refugees: to the loss, maintenance, and adaptation of refugees’ ethnobiological knowledge, and to its significance for refugees’ wellbeing. This study focuses on cosmetics and remedies used to heal skin afflictions that are traditionally used by Sahrawi refugees displaced in South Western Algerian refugee camps.Methods
The research methods included a structured survey carried out with 37 refugee households, semi-structured interviews with 77 refugees, 24 retrospective interviews with refugees and other knowledgeable informants, and a voucher specimen collection of the plants and products cited.Results
We recorded the use of 55 plant species, nine animal species, and six mineral products used within the three main use categories discussed in this paper: 1) Remedies for health issues that are typical of the desert environment where the Sahrawi once lived as nomads and now live as refugees (e.g. eye afflictions); 2) Remedies for wounds that are influenced by the Sahrawi’s recent history of guerrilla warfare; and 3) Cosmetics and products used for body care, decoration and perfuming (e.g. hair care, teeth cleansing, henna use) and for aromatizing the air inside of tents and which are widely used in everyday life and social practices.Conclusions
We discuss the changes that have occurred in the patterns of use and procurement of these products with exile and sedentarization in refugee camps, and conclude that refugees are not simply passive recipients of national and international aid, but rather struggle to maintain and recover their traditional ethnobiological practices in exile. Finally, we suggest further research into the ethnobiological practices and knowledge of displaced populations.Resumen
Sanando las heridas de guerra y perfumando el exilio: el uso de productos vegetales, animales y minerales con fines de perfumería, cosmética y curativos de la piel entre los refugiados saharauis del Sáhara Occidental.Antecedentes
Durante la última década ha habido un creciente interés en los estudios etnobiológicos de los conocimientos y prácticas de las personas que migran. Dentro de esta tendencia, los estudiosos han prestado relativamente menor atención a las personas desplazadas y a los refugiados: a la pérdida, el mantenimiento y la adaptación de sus conocimientos etnobiológicos, y su importancia para el bienestar de los refugiados. Este estudio se centra en los cosméticos y remedios para curar problemas de la piel tradicionalmente utilizados por los refugiados saharauis en los campamentos de desplazados al sudoeste de Argelia.Métodos
Los métodos de investigación que se utilizaron son: una encuesta estructurada con 37 familias de refugiados, entrevistas semi-estructuradas con 77 refugiados, 24 entrevistas retrospectivas con refugiados e informantes conocedores, y una colección de muestra de las plantas y productos citados.Resultados
Se registró el uso de 55 especies vegetales, nueve especies animales, y seis productos minerales utilizados en tres principales categorías de usos: 1) Recursos contra los problemas de salud característicos del entorno desértico donde una vez vivieron los saharauis como nómadas y donde ahora viven como refugiados (por ejemplo problemas en los ojos); 2) Remedios para heridas que reflejan la historia reciente de guerra de guerrilla de los nómadas saharauis; y 3) Cosméticos y productos utilizados para el cuidado del cuerpo, decoración y perfumes (por ejemplo, atención al cabello, limpieza de dientes, uso del henna) y como aromatizantes del aire al interior de las tiendas, que son ampliamente utilizados en la vida y las prácticas sociales cotidianas de los refugiados.Conclusiones
En la discusión, se analizan los cambios que se han producido en los patrones de uso y en la adquisición de estos productos durante el exilio. Llegamos a la conclusión de que los refugiados no son recipientes pasivos de la ayuda nacional e internacional, sino más bien luchan para mantener y recuperar sus prácticas tradicionales etnobiológicas en el exilio. Finalmente, sugerimos nuevas direcciones para la investigación de las prácticas y los conocimientos etnobiológicos de las poblaciones desplazadas.160.
During a random survey of entomopathogenic nematodes in the provinces of Sichuan and Gansu (eastern Tibet) in 2004, soil samples from several sites were collected and tested for the incidence of entomopathogenic nematodes. A new species was collected in this survey and it is described herein as Steinernema cholashanense n. sp. Steinernema cholashanense n. sp. is characterized by morphology and morphometry of the IJ and male. For the IJ, the new species can be recognized by the average body length 843 microm, esophagus length 125 microm, H%=39% and E%=81%. The lateral field pattern is 2, 5, 7, 4, 2. The male of the first generation is characterized by spicule shape and length and especially with prominent velum and the presence of a mucron on both generations. The average body length of the IJ of S. cholashanense n. sp. (843 microm) is shorter than that of S. oregonense (980 microm), S. kraussei (951 microm) and S. litorale (909 microm), similar to that of S. feltiae (849 microm), but longer than that of S. weiseri (740 microm), S. jollietti (711 microm) and S. hebeiense (658 microm). Esophagus length of the new species (125 microm) is closer to that of S. jollieti (123 microm) but longer than that of S. weiseri (113 microm) and shorter than that of S. oregonense (132 microm), S. kraussei (134 microm) and S. feltiae (136 microm). E% of the new species (81) is similar to that of S. kraussei (80), but smaller than that of S. jollieti (88), S. weiseri (95), S. oregonense (100) and S. feltiae (119). Spicule head length of the new species is almost the same as its width, this character is similar to that of S. kraussei but it is different from this species by its prominent velum. The new species can be recognized further by characteristics of sequences of ITS and D2D3 regions and cross hybridization with closely related species, S. feltiae, S. kraussei and S. oregonense. 相似文献