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71.
The electrocardiogram (ECG) interpretation in patients with implantable cardioverter defibrillator (ICD) is often a puzzling problem. The difficulty of the device function evaluation further increases in the presence of unfamiliar timing cycles and additional functions. We present an interesting ECG with a special function of a Biotronik ICD devices called the thoracic impedance monitoring, and demonstrate its behavior in a patient with atrial fibrillation, pacing beats, ventricular ectopic beats, and couple of ventricular beats. This report shows unexceptional occurrence of tricky ECG finding in patient with Biotronik ICDs.  相似文献   
72.
Gliomas attract brain‐resident (microglia) and peripheral macrophages and reprogram these cells into immunosuppressive, pro‐invasive cells. M‐CSF (macrophage colony‐stimulating factor, encoded by the CSF1 gene) has been implicated in the control of recruitment and polarization of macrophages in several cancers. We found that murine GL261 glioma cells overexpress GM‐CSF (granulocyte–macrophage colony‐stimulating factor encoded by the CSF2 gene) but not M‐CSF when compared to normal astrocytes. Knockdown of GM‐CSF in GL261 glioma cells strongly reduced microglia‐dependent invasion in organotypical brain slices and growth of intracranial gliomas and extended animal survival. The number of infiltrating microglia/macrophages (Iba1+ cells) and intratumoural angiogenesis were reduced in murine gliomas depleted of GM‐CSF. M1/M2 gene profiling in sorted microglia/macrophages suggests impairment of their pro‐invasive activation in GM‐CSF‐depleted gliomas. Deficiency of M‐CSF (op/op mice) did not affect glioma growth in vivo and the accumulation of Iba1+ cells, but impaired accumulation of Iba1+ cells in response to demyelination. These results suggest that distinct cytokines of the CSF family contribute to macrophage infiltration of tumours and in response to injury. The expression of CSF2 (but not CSF1) was highly up‐regulated in glioblastoma patients and we found an inverse correlation between CSF2 expression and patient survival. Therefore we propose that GM‐CSF triggers and drives the alternative activation of tumour‐infiltrating microglia/macrophages in which these cells support tumour growth and angiogenesis and shape the immune microenvironment of gliomas. Copyright © 2013 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
73.
Recombinant human erythropoietin (rhEPO) treatment of hemodialyzed (HD) patients normalizes the altered phenotype of CD4+ lymphocytes and restores the balance of Th1/Th2 cytokines. We decided to test how the presence of rhEPO in cell culture modulates cytokine production of CD4+ lymphocytes in HD patients with stable hemoglobin level and expression of activation antigens of stimulated CD4+ lymphocytes similar to those observed in healthy individuals. We also tested whether the presence of rhEPO in cell culture protects stimulated CD4+ lymphocytes of HD patients from apoptosis. Peripheral blood mononuclear cells (PBMC) of HD patients were stimulated with an immobilized anti-CD3 antibody with or without addition of rhEPO. The percentage of apoptotic CD4+ lymphocytes and the level of Th1/Th2 cytokines in culture supernatants were measured with flow cytometry. HD patients showed a decrease in the percentage of apoptotic CD4+ cells after stimulation with the anti-CD3 antibody combined with rhEPO. The level of IFN-γ and IL-10 was increased while the level of TNF-α was decreased in the presence of rhEPO in cell culture from HD patients. These results confirm the role of rhEPO signaling in T lymphocytes of HD patients.  相似文献   
74.
One of the basic rules of transfusion is to prevent alloimmunisation by highly immunogenic RhD antigen and not to transfuse RhD negative individuals with RhD positive blood. In some cases the expression of this antigen is so weak that it is undetectable in routine serological tests. The paper presents an algorithm for mass DNA testing with the purpose of identifying donors with low RhD expression. The screening is based on RHD gene detection (absent in RhD negative Caucasians) in DNA isolated from pools of 96 plasma samples from blood donors identified as RhD negative by the routine serological methods in Blood Transfusion Centers. Such procedure substantially reduces the costs. Plasma samples can be brought from the territory of the whole country, stored and accumulated for testing in one selected center. The cost would amount to approximately 25 PLN per donor. The test is performed once for each RhD negative individual. It is estimated that such persons will represent approximately 0.2% of RhD negative donors.  相似文献   
75.
BackgroundCytomegalovirus (CMV) reactivation remains one of the most frequent complications after allogeneic hematopoietic stem cell transplantation (HSCT).MethodsAn analysis of the pre-transplant risk factors of CMV reactivation was performed in 98 patients aged 0.5–22 years (median 10.5) undergoing allogeneic HSCT. CMV reactivation was tested by assessing viral load using PCR method. Following factors were analyzed: type of conditioning, graft source, donor type, use of T-depletion and CMV-serostatus of the donor and recipient. Each factor was assigned from 0 to 2 points. Based on total score for each patient, CMV reactivation risk scale was developed, and two groups with low (LR) and high (HR) risk were determined.ResultsCMV reactivation was seen in 25 patients (24.5%). The significant risk factors for CMV reactivation were: CMV-positive recipient (p<0.001), unrelated donor (p<0.002), use of ATG (p<0.002) and PBSC (p<0,01). In the HR group the incidence of reactivation CMV was significantly higher than in LR group (47.8% vs. 5.4%, p<0.001).ConclusionsCMV seropositivity of the recipient was an independent predictor factor of CMV reactivation. The use of risk point scale of CMV reactivation allows for identification of patients with the higher risk of CMV reactivation.  相似文献   
76.
International Journal of Legal Medicine - Sudden cardiac death (SCD) related to atherosclerotic coronary artery disease (ACAD) resulting in myocardial infarction is the most prevalent cause of...  相似文献   
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Abstract

The Dsb protein family in prokaryotes catalyzes the generation of disulfide bonds between thiol groups of cysteine residues in nascent proteins, ensuring their proper three-dimensional structure; these bonds are crucial for protein stability and function. The first Dsb protein, Escherichia coli DsbA, was described in 1991. Since then, many details of the bond-formation process have been described through microbiological, biochemical, biophysical and bioinformatics strategies. Research with the model microorganism E. coli and many other bacterial species revealed an enormous diversity of bond-formation mechanisms. Research using Dsb protein engineering has significantly helped to reveal details of the disulfide bond formation. The first part of this review presents the research that led to understanding the mechanism of action of DsbA proteins, which directly transfer their own disulfide into target proteins. The second part concentrates on the mechanism of electron transport through the cell cytoplasmic membrane. Third and lastly, the review discusses the contribution of this research towards new antibacterial agents.  相似文献   
80.
Nematode worms of the genus Trichinella are one of the most widespread zoonotic pathogens. Natural transmission between hosts can only occur through the ingestion of infected meat. To date, two Trichinella species are known to be etiological agents of disease among domestic animals and wildlife in Poland: T. spiralis and T. britovi. In the last decades, since the administration of an oral vaccination against rabies, the red fox population in Poland has increased exponentially. The study area covers the Nowy Targ region: a mountainous area (585–1138 m above the sea) in southern Poland. Of 24 red foxes examined in the study, four were infected with Trichinella isolates: three were identified as T. britovi and one as T. pseudospiralis. The muscle of red foxes infected with T. britovi harboured 2.75, 3.11, 4.4 LPG and with T. pseudospiralis 0.36 LPG. Trichinella larvae were identified at species level by genomic and mitochondrial multiplex PCR, the products of which were sequenced for comparison with other sequences available in GenBank. The sequences obtained from the Polish T. pseudospiralis isolate, deposited in GenBank under the accession numbers JQ809660.1 and JQ809661.1, matched sequences already published in GenBank. Sequence comparison showed a 100% match with the large subunit ribosomal RNA gene of T. pseudospiralis isolate ISS 013, and a 96–95% match with those of T. pseudospiralis isolates ISS 141 and ISS 470. This is the first report of the identification of T. pseudospiralis larvae from red fox in Poland.  相似文献   
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