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911.
Fabiana Martins de Paula Fernanda de Mello Malta Priscilla Duarte Marques Renata Barnabé Sitta Jo?o Renato Rebello Pinho Ronaldo César Borges Gryschek Pedro Paulo Chieffi 《Memórias do Instituto Oswaldo Cruz》2015,110(2):272-274
This study aimed to evaluate the use of conventional polymerase chain reaction (cPCR)
and real-time quantitative PCR (qPCR) in the diagnosis of human strongyloidiasis from
stool samples in tropical areas. Stool samples were collected from individuals and
were determined to be positive for Strongyloides stercoralis (group I), negative for
S. stercoralis (group II) and positive for other enteroparasite species (group III).
DNA specific to S. stercoralis was found in 76.7% of group I samples by cPCR and in
90% of group I samples by qPCR. The results show that molecular methods can be used
as alternative tools for detecting S. stercoralis in human stool samples in tropical
areas. 相似文献
912.
Moneeb A. K. Othman Beata Grygalewicz Barbara Pienkowska-Grela Martina Rincic Katharina Rittscher Joana B. Melo Isabel M. Carreira Britta Meyer Watek Marzena Thomas Liehr 《The journal of histochemistry and cytochemistry》2015,63(5):384-390
MLL (mixed-lineage-leukemia) gene rearrangements are typical for acute leukemia and are associated with an aggressive course of disease, with a worse outcome than comparable case, and thus require intensified treatment. Here we describe a 69-year-old female with adult B cell precursor acute lymphoblastic leukemia (BCP-ALL) with hyperleukocytosis and immunophenotype CD10- and CD19+ with cryptic MLL rearrangements. G-banding at the time of diagnosis showed a normal karyotype: 46,XX. Molecular cytogenetics using multitude multicolor banding (mMCB) revealed a complex rearrangement of the two copies of chromosome 11. However, a locus-specific probe additionally identified that the MLL gene at 11q23.3 was disrupted, and that the 5′ region was inserted into the chromosomal sub-band 4q21; thus the aberration involved three chromosomes and five break events. Unfortunately, the patient died six months after the initial diagnosis from serious infections and severe complications. Overall, the present findings confirm that, by far not all MLL aberrations are seen by routine chromosome banding techniques and that fluorescence in situ hybridization (FISH) should be regarded as standard tool to access MLL rearrangements in patients with BCP-ALL. 相似文献
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914.
915.
Intravital microscopy allows imaging of biological phenomena within living animals, including host–parasite interactions. This has advanced our understanding of both, the function of lymphoid organs during parasitic infections, and the effect of parasites on such organs to allow their survival. In parasitic research, recent developments in this technique have been crucial for the direct study of host–parasite interactions within organs at depths, speeds and resolution previously difficult to achieve. Lymphoid organs have gained more attention as we start to understand their function during parasitic infections and the effect of parasites on them. In this review, we summarise technical and biological findings achieved by intravital microscopy with respect to the interaction of various parasites with host lymphoid organs, namely the bone marrow, thymus, lymph nodes, spleen and the mucosa‐associated lymphoid tissue, and present a view into possible future applications. 相似文献
916.
917.
Cabras T Fanali C Monteiro JA Amado F Inzitari R Desiderio C Scarano E Giardina B Castagnola M Messana I 《Journal of proteome research》2007,6(7):2472-2480
Histatin 1 (His-1) derivatives showing serial mass increases of 80.0 +/- 0.1 Da were detected in human saliva by HPLC-ESI-MS. The same derivatives were also found in granules of submandibular glands and secretions of submandibular/sublingual glands, but not in granules and secretions of parotid glands. Only one phosphate group was present in His-1 and its derivatives, since treatment with alkaline phosphatase provided an 80.0 Da mass decrease. His-1 derivatives were almost completely transformed into His-1 by treatment with 1 M HCl at 100 degrees C, suggesting the presence of O-sulfotyrosine, which is more labile than phospho-Tyr to acidic hydrolysis. CE-MS analysis of pronase extensive digestion of derivatives confirmed the presence of sulfotyrosine. Derivatives were digested by trypsin, proteinase K, and protease V-8 and analyzed by different MS strategies. The results allowed locating sulfation on the last four tyrosines (Tyr 27, 30, 34, and 36). This study is the first report of the gland-specific sulfation of a salivary phosphopeptide in vivo. 相似文献
918.
Sjöfn Sigurgísladóttir Malta Konráòsdóttir Ásbjörn Jónsson Jakob K. Kristjánsson Einar Matthiasson 《Biotechnology letters》1993,15(4):361-366
Summary Several bacteria strains were choosen from pre-selected strains for further testing and characterisation. Hydrolytic activity of lipases from thermophilic bacteria was examined using olive oil as a substrate at different reaction temperatures. Alcoholytic activity was also investigated. Lipases from thermophilic bacteria have been successfully produced on a large scale. To be able to predict if these lipases can be used for transesterification reactions, these preparations need to be purified further or to be cloned. 相似文献
919.
Moscoso JA Mikkelsen H Heeb S Williams P Filloux A 《Environmental microbiology》2011,13(12):3128-3138
Acute bacterial infections are associated with motility and cytotoxicity via the type III secretion system (T3SS), while chronic infections are linked to biofilm formation and reduced virulence. In Pseudomonas aeruginosa, the transition between motility and sessility involves regulatory networks including the RetS/GacS sensors, as well as the second messenger c-di-GMP. The RetS/GacS signalling cascade converges on small RNAs, RsmY and RsmZ, which control a range of functions via RsmA. A retS mutation induces biofilm formation, and high levels of c-di-GMP produce a similar response. In this study, we connect RetS and c-di-GMP pathways by showing that the retS mutant displays high levels of c-di-GMP. Furthermore, a retS mutation leads to repression of the T3SS, but also upregulates the type VI secretion system (T6SS), which is associated with chronic infections. Strikingly, production of the T3SS and T6SS can be switched by artificially modulating c-di-GMP levels. We show that the diguanylate cyclase WspR is specifically involved in the T3SS/T6SS switch and that RsmY and RsmZ are required for the c-di-GMP-dependent response. These results provide a firm link between the RetS/GacS and the c-di-GMP pathways, which coordinate bacterial lifestyles, as well as secretion systems that determine the infection strategy of P. aeruginosa. 相似文献
920.