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51.
Jain P Javdan M Feger FK Chiu PY Sison C Damle RN Bhuiya TA Sen F Abruzzo LV Burger JA Rosenwald A Allen SL Kolitz JE Rai KR Chiorazzi N Sherry B 《Haematologica》2012,97(4):599-607
Background
The levels and clinical relevance of Th17 cells and other interleukin-17-producing cells have not been analyzed in chronic lymphocytic leukemia. The objective of this study was to quantify blood and tissue levels of Th17 and other interleukin-17-producing cells in patients with this disease and correlate blood levels with clinical outcome.Design and Methods
Intracellular interleukin-17A was assessed in blood and splenic mononuclear cells from patients with chronic lymphocytic leukemia and healthy subjects using flow cytometry. Interleukin-17A-producing cells were analyzed in formalin-fixed, paraffin-embedded spleen and lymph node sections using immunohistochemistry and immunofluorescence.Results
The absolute numbers of Th17 cells in peripheral blood mononuclear cells and the percentages of Th17 cells in spleen cell suspensions were higher in patients with chronic lymphocytic leukemia than in healthy subjects; in six out of eight paired chronic lymphocytic leukemia blood and spleen sample comparisons, Th17 cells were enriched in spleen suspensions. Circulating Th17 levels correlated with better prognostic markers and longer overall survival of the patients. Two “non-Th17” interleukin-17-expressing cells were identified in chronic lymphocytic leukemia spleens: proliferating cells of the granulocytic lineage and mature mast cells. Granulocytes and mast cells in normal spleens did not express interleukin-17. Conversely, both chronic lymphocytic leukemia and healthy lymph nodes contained similar numbers of interleukin-17+ mast cells as well as Th17 cells.Conclusions
Th17 cells are elevated in chronic lymphocytic leukemia patients with better prognostic markers and correlate with longer survival. Furthermore, non-Th17 interleukin-17A-expressing cells exist in chronic lymphocytic leukemia spleens as maturing granulocytes and mature mast cells, suggesting that the microenvironmental milieu in leukemic spleens promotes the recruitment and/or expansion of Th17 and other IL-17-expressing cells. The pathophysiology of Th17 and non-Th17-interleukin-producing cells in chronic lymphocytic leukemia and their distributions and roles in this disease merit further study. 相似文献52.
53.
Kleinstiver BP Wolfs JM Kolaczyk T Roberts AK Hu SX Edgell DR 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(21):8061-8066
Targeted manipulation of complex genomes often requires the introduction of a double-strand break at defined locations by site-specific DNA endonucleases. Here, we describe a monomeric nuclease domain derived from GIY-YIG homing endonucleases for genome-editing applications. Fusion of the GIY-YIG nuclease domain to three-member zinc-finger DNA binding domains generated chimeric GIY-zinc finger endonucleases (GIY-ZFEs). Significantly, the I-TevI-derived fusions (Tev-ZFEs) function in vitro as monomers to introduce a double-strand break, and discriminate in vitro and in bacterial and yeast assays against substrates lacking a preferred 5'-CNNNG-3' cleavage motif. The Tev-ZFEs function to induce recombination in a yeast-based assay with activity on par with a homodimeric Zif268 zinc-finger nuclease. We also fused the I-TevI nuclease domain to a catalytically inactive LADGLIDADG homing endonuclease (LHE) scaffold. The monomeric Tev-LHEs are active in vivo and similarly discriminate against substrates lacking the 5'-CNNNG-3' motif. The monomeric Tev-ZFEs and Tev-LHEs are distinct from the FokI-derived zinc-finger nuclease and TAL effector nuclease platforms as the GIY-YIG domain alleviates the requirement to design two nuclease fusions to target a given sequence, highlighting the diversity of nuclease domains with distinctive biochemical properties suitable for genome-editing applications. 相似文献
54.
Nair P Davies AR Beca J Bellomo R Ellwood D Forrest P Jackson A Pye R Seppelt I Sullivan E Webb S 《Intensive care medicine》2011,37(4):648-654
Purpose
To describe the technical challenges, efficacy, complications and maternal and infant outcomes associated with extracorporeal membrane oxygenation (ECMO) for severe adult respiratory distress syndrome (ARDS) in pregnant or postpartum patients during the 2009 H1N1 pandemic.Methods
Twelve critically ill pregnant and postpartum women were included in this retrospective observational study on the application of ECMO for the treatment of severe ARDS refractory to standard treatment. The study was conducted at seven tertiary hospitals in Australia and New Zealand.Results
Of the 12 patients treated with ECMO, 7 (58%) were pregnant and 5 (42%) were postpartum. Their median (interquartile range [IQR]) age was 29 (26?C33)?years, 6 (50%) were obese. Two patients were initially treated with veno-arterial (VA) ECMO. All others received veno-venous (VV) ECMO with one or two drainage cannulae. ECMO circuit-related complications were rare, circuit change was needed in only two cases and there was no sudden circuit failure. On the other hand, bleeding was common, leading to relatively large volumes of packed red blood cell transfusion (median [IQR] volume transfused was 3,499 [1,451?C4,874]?ml) and was the main cause of death (three cases). Eight (66%) patients survived to discharge and seven were ambulant, with normal oxygen saturations. The survival rate of infants whose mothers received ECMO was 71% and surviving infants were discharged home with no sequelae.Conclusions
The use of ECMO for severe ARDS in pregnant and postpartum women was associated with a 66% survival rate. The most common cause of death was bleeding. Infants delivered of mothers who had received ECMO had a 71% survival rate and, like their mothers, had no permanent sequelae at hospital discharge. 相似文献55.
Matjaz Sever Hagop Kantarjian Sherry Pierce Nitin Jain Zeev Estrov Jorge Cortes Srdan Verstovsek 《International journal of hematology》2009,90(4):522-525
Cytogenetic abnormalities in patients with essential thrombocythemia (ET) are infrequent. Their role in survival of patients
and disease transformation is not extensively studied. We describe cytogenetic abnormalities in 172 patients with ET at a
single institution. At presentation nine (5.2%) patients had cytogenetic abnormality and three (1.7%) additional patients
acquired them during follow-up. Survival of patients with cytogenetic changes at presentation did not differ when compared
to the patients with normal karyotype. The more common were abnormalities of chromosome 9 (n = 4), 20 (n = 2), 5 (n = 2), and complex abnormalities (n = 2). Forty-one patients (23.8%) had additional cytogenetic tests performed for monitoring purposes during follow-up. Five
patients (2.9%) with normal karyotype transformed to myelofibrosis (MF) without developing new cytogenetic changes at transformation.
Two patients (1.2%) with normal karyotypes at presentation transformed to myelodysplastic syndrome and acute myeloid leukemia,
respectively. Both acquired complex cytogenetic changes at the time of transformation. There is no rationale for repeating
cytogenetic tests in ET patients on follow up, unless blood cell count changes suggest possible transformation. 相似文献
56.
57.
Gabriela Lima de Melo Ghisi Sherry L. Grace Scott Thomas Michael F. Evans Heather Sawula Paul Oh 《Patient education and counseling》2014
Objective
To (1) describe cardiac rehabilitation (CR) participant information needs, (2) investigate whether CR providers are cognizant of patient's information needs and preferred delivery formats, and (3) investigate whether patient information needs change over the course of CR.Methods
In this cross-sectional study, 306 CR patients and 28 CR providers completed a survey. The survey consisted of the Information Needs in CR (INCR) questionnaire, and items about preferred education delivery formats.Results
Low-income CR participants had significantly greater information needs than high-income participants. CR providers were cognizant of patient information needs, except patients did desire more information on diagnosis and treatment than providers perceived (p < 0.01). Books, lectures and discussion were identified as the preferred delivery formats by both patients and providers. There were some significant differences in patient information needs over the course of the program, particularly in relation to concerns and risk factors.Conclusion
CR patients desire information in many areas, particularly regarding emergency/safety and diagnosis/treatment. CR providers were highly cognizant of patient information needs; however, these do change over time.Practice implications
These findings could inform evaluation and improvement of CR education programming, to ensure programs are meeting patient information needs across all stages of recovery. 相似文献58.
Developing methods that can detect compartmentation of metabolic pathways in intact tissues may be important for understanding energy demand and supply. In this study, we investigated compartmentation of glycolysis and glycogenolysis in the isolated perfused rat heart using (13)C NMR isotopomer analysis. Rat hearts previously depleted of myocardial glycogen were perfused with 5.5 mm [U-(13)C]glucose plus 50 mU/mL insulin until newly synthesized glycogen recovered to new steady-state levels ( approximately 60% of pre-depleted values). After a short wash-out period, the perfusate glucose was then switched to [1-(13)C]glucose, and glycolysis and glycogenolysis were stimulated by addition of glucagon (1 microg/ml). A (13)C NMR multiplet analysis of the methyl resonance of lactate provided an estimate of pyruvate derived from glucose vs glycogen while a multiplet analysis of the C4 resonance of glutamate provided an estimate of acetyl-CoA derived from glycolytic pyruvate vs glycogenolytic pyruvate. These two indices were not equivalent and their difference was further magnified in the presence of insulin during the stimulation phase. These combined observations are consistent with functional compartmentation of glycolytic and glycogenolytic enzymes that allows pyruvate generated by these two processes to be distinguished at the level of lactate and acetyl-CoA. 相似文献
59.
A conserved protein network controls assembly of the outer kinetochore and its ability to sustain tension 总被引:5,自引:0,他引:5
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Cheeseman IM Niessen S Anderson S Hyndman F Yates JR Oegema K Desai A 《Genes & development》2004,18(18):2255-2268
Kinetochores play an essential role in chromosome segregation by forming dynamic connections with spindle microtubules. Here, we identify a set of 10 copurifying kinetochore proteins from Caenorhabditis elegans, seven of which were previously uncharacterized. Using in vivo assays to monitor chromosome segregation, kinetochore assembly, and the mechanical stability of chromosome-microtubule attachments, we show that this copurifying protein network plays a central role at the kinetochore-microtubule interface. In addition, our analysis suggests that the network is comprised of three groups of proteins that contribute in distinct ways to this interface: KNL proteins act after the assembly of centromeric chromatin to generate the core of the microtubule-binding interface, MIS proteins control the rate and extent of formation of this interface, and NDC proteins are necessary to sustain tension during interactions with spindle microtubules. We also purify a similar set of associated proteins from human cells that includes four novel proteins and has recognizable homologs from each functional class. Thus, this protein network is a conserved constituent of the outer kinetochore, and the functions defined by our analysis in C. elegans are likely to be widely relevant. 相似文献
60.
Chi XS Hu A Bolar TV Al-Rimawi W Zhao P Tam JS Rappaport R Cheng SM 《Journal of clinical microbiology》2005,43(5):2345-2349
One-hundred five influenza B-positive specimens obtained from southeast Asia in 2002 were categorized on the basis of DNA sequencing of HA1 gene as well as real-time PCR analysis of the NA gene. Phylogenetic analysis of the HA1 gene sequences showed that the majority of the viruses (96.2%) belonged to the B/Victoria/2/87 lineage, while a smaller percentage of the viruses (3.8%) belonged to the B/Yamagata/16/88 lineage. The B/Yamagata/16/88 viruses displayed significant antigenic drift in the deduced amino acid sequences of the HA1 protein, and the B/Victoria/2/87-like viruses consisted of B/Hong Kong/1351/02-like (72.3%) and B/Hong Kong/330/01-like (27.7%) viruses. The B/Hong Kong/1351/02-like viruses were reassortants with the HA gene belonging to the B/Victoria/2/87 lineage and the NA gene belonging to the B/Yamagata/16/88 lineage, whereas both the HA and NA genes of B/Hong Kong/330/01 virus belonged to the B/Victoria/2/87 lineage. In this study, however, all the B/Hong Kong/330/01-like isolates exhibited the B/Yamagata/16/88-like NA gene, which likely resulted from reassortment of B/Hong Kong/330/01 and B/Hong Kong/1351/02 viruses during coinfection. Additional molecular characterization of the six internal genes showed that the M, NS, PA, and PB2 genes of the new variants were B/Hong Kong/1351/02 in origin, whereas the NP and PA genes retained the B/Hong Kong/330/01 origin. Interestingly, these new variants all appeared late in the year 2002. These results support the notion that influenza B viruses continued to evolve through antigenic drift and shift. 相似文献