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991.
992.
GB Boylan L Burgoyne C Moore B O’Flaherty JM Rennie 《Acta paediatrica (Oslo, Norway : 1992)》2010,99(8):1150-1155
Objective: To examine the extent of EEG monitoring in neonatal intensive care units (NICUs), and to survey the level of experience and training of those using it. Study design: A web‐based survey, the link to which was circulated via e‐mail, personal contact, specialist societies and professional groups. Survey data were exported to SPSS for analysis. Results: In total 210 surveys were analysed; 124 from Europe, 54 from the US. Ninety percent of respondents had access to either EEG or aEEG monitoring; 51% had both. EEG was mainly interpreted by neurophysiologists (72%) whereas aEEG was usually interpreted by neonatologists (80%). Only 9% of respondents reported that they felt ‘very confident’ in their ability to interpret aEEG/EEG with 31% reporting that they were ‘not confident’. Half had received no formal training in EEG. Conclusion: Both aEEG and conventional EEG were used extensively in the NICUs surveyed for this study. Most of the survey respondents were not confident in their ability to interpret EEGs despite the fact that they used monitoring routinely. There is an urgent need for a structured and appropriately targeted training programme in EEG methodologies and EEG interpretation for neonatal intensive care unit staff. 相似文献
993.
Kun Shi Karla CS Queiroz Joris JTH Roelofs Carel JM van Noesel Dirk J Richel C Arnold Spek 《The Journal of pathology》2014,234(3):398-409
Protease‐activated receptor‐2 (PAR‐2) is a G protein‐coupled receptor that functions as a cell‐surface sensor for coagulation factors and other proteases associated with the tumour microenvironment. Pancreatic cancer cells express high levels of PAR‐2 and activation of PAR‐2 may induce their proliferation and migration. Interestingly, however, PAR‐2 expression is increased in stroma‐rich pancreatic cancer regions, suggesting a potential role of PAR‐2 in the tumour microenvironment. Here, we assessed the importance of PAR‐2 in the stromal compartment by utilizing an orthotopic pancreatic cancer model, in which tumour cells are PAR‐2‐positive, whereas stromal cells are PAR‐2‐negative. We assessed tumour weight and volume and analysed proliferation and (lymph)angiogenesis both in vivo and in vitro. We show that genetic ablation of PAR‐2 from the stromal compartment inhibits primary tumour growth, which is accompanied by reduced vascularization in primary tumours and reduced in tube formation of vascular endothelial cells in vitro. In contrast to smaller primary tumours, the number of lymph node metastases was increased in PAR‐2‐deficient animals, which was accompanied by an increased number of lymphatic vessels. In vitro tube‐formation assays show that PAR‐2 does not inhibit the intrinsic tube‐forming capacity of lymphatic endothelial cells, but that PAR‐2 actually inhibits cancer cell‐induced tube formation. Overall, stromal PAR‐2 thus plays a dual role in pancreatic cancer development by potentiating primary tumour growth but limiting lymphangiogenesis and subsequent lymph node metastasis. Our data identify a novel role of PAR‐2 in the tumour microenvironment and pinpoint PAR‐2 as a negative regulator of lymphangiogenesis. Copyright © 2014 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
994.
Skeletal muscle is an attractive target for somatic gene transfer of both
acquired and inherited disorders. Direct injection of adenoviral vectors in
the skeletal muscle leads to recombinant gene expression in a large number
of muscle fibers. Transgene expression has been transient in most organs
and associated with substantial inflammation when experiments are performed
in adult immune competent mice. In this report, we utilize a variety of in
vivo and in vitro models of T and B cell function to characterize the
nature of the immune response to adenoviral vectors injected into murine
skeletal muscle. Cellular immunity dependent on CD4+ and CD8+ T cells
contributes to the loss of recombinant gene expression and the development
of localized inflammation. Antigen specific activation of T cells occurs to
both viral proteins and the reporter gene beta-galactosidase. Systemic
levels of neutralizing antibody to the capsid proteins of the vector are
also generated. Destructive immune responses responsible for loss of
transgene expression are largely directed against beta-galactosidase in
that transgene expression was stable when beta-galactosidase was eliminated
as a neoantigen in mice transgenic for lacZ. A strategy to prevent the
cellular and humoral immunity to this therapy was developed based on
transiently ablating CD4+ T cell activation at the time of vector delivery.
Encouraging results were obtained when vector was administered with one of
several immune modulating agents including cyclophosphamide, mAb to CD4+
cells, and mAb to CD40 ligand. These studies indicate that cellular and
humoral immune responses are elicited in the context of gene therapy
directed to skeletal muscle with adenoviral vectors. Transient ablation of
CD4+ T cell activation prevents the effects responses of the CD8+ T and B
cells.
相似文献
995.
Microsatellite instability and mutation analysis of hMSH2 and hMLH1 in patients with sporadic, familial and hereditary colorectal cancer 总被引:17,自引:0,他引:17
Moslein G; Tester DJ; Lindor NM; Honchel R; Cunningham JM; French AJ; Halling KC; Schwab M; Goretzki P; Thibodeau SN 《Human molecular genetics》1996,5(9):1245-1252
To date, at least four genes involved in DNA mismatch repair, hMSH2, hMLH1,
hPMS1 and hPMS2, have been demonstrated to be altered in the germline of
patients with hereditary nonpolyposis colorectal cancer (HNPCC).
Additionally, defective mismatch repair is thought to account for the
observation of microsatellite instability (MIN) in tumors from these
patients. The genetic defect responsible for the MIN+ phenotype in sporadic
colorectal cancer, however, has yet to be clearly delineated. In order to
better understand the role of somatic and germline alterations within hMSH2
and hMLH1 in the process of colorectal tumorigenesis, we examined the
entire coding regions of both of these genes in seven patients with MIN+
sporadic colorectal cancer, 19 patients with familial colorectal cancer,
and 20 patients meeting the strict Amsterdam criteria for HNPCC. Thirteen
germline, two somatic, and four neutral alterations were identified. The
two somatic mutations occurred in patients having familial cancer, while
the germline mutations were distributed among one sporadic (14%), three
familial (16%), and nine HNPCC (45%) cases. All patients with identified
mutations in the mismatch repair genes, whose tumors were available for
analysis, demonstrated MIN. On the other hand, we could not identify
mutations in the subset of clinically defined HNPCC patients with MIN
negative tumors nor in the majority (6/7) of MIN+ sporadic tumors.
相似文献
996.
Pastor D Viso-León MC Jones J Jaramillo-Merchán J Toledo-Aral JJ Moraleda JM Martínez S 《Stem cell reviews》2012,8(2):445-458
Motorneuron degenerative diseases, such as amyotrophic lateral sclerosis (ALS), are characterized by the progressive and rapid loss of motor neurons in the brain and spinal cord, leading to paralysis and death. GDNF (glial cell line derived neurotrophic factor) has been previously shown to be capable of protecting motor-neurons in ALS animal models although its delivery to the spinal cord after systemic administration is blocked by the blood brain barrier. Thus, it is necessary to develop new neurotrophic approaches to protect these motor neurons from death. Bone marrow-derived stem cells have been shown to be capable of improving a large variety of neurodegenerative disorders through neurotrophic mediated mechanisms. Here we analyzed the effect of transplanting whole bone marrow or cultured mesenchymal stem cells into the spinal cord of a motor neuron degenerative mouse model. Motor functions were analyzed using various behavior tests for several weeks after transplantation. We observed that bone marrow, and to a lesser degree mesenchymal stem cell, treated mice improved significantly in the motor tests performed, coinciding with a higher GDNF immunoreactivity in the grafted spinal cord. In several cases, the treated spinal cords were extracted, the engrafted bone marrow cells isolated and cultured, and finally re-transplanted into the spleen of immunodeficient mice. Re-grafted cells were detected in the host spleen, bloodstream and bone marrow, demonstrating a phenotypic stability. Thus, bone marrow cells do not suffer significant phenotypic modifications and is an efficient procedure to ameliorate motor-neuron degeneration, making it a possible therapeutic approach. 相似文献
997.
Andresen BS; Bross P; Udvari S; Kirk J; Gray G; Kmoch S; Chamoles N; Knudsen I; Winter V; Wilcken B; Yokota I; Hart K; Packman S; Harpey JP; Saudubray JM; Hale DE; Bolund L; Kolvraa S; Gregersen N 《Human molecular genetics》1997,6(5):695-707
Medium-chain acyl-CoA dehydrogenase (MCAD) deficiency is the most commonly
recognized defect of mitochondrial beta-oxidation. It is potentially fatal,
but shows a wide clinical spectrum. The aim of the present study was to
investigate whether any correlation exists between MCAD genotype and
disease phenotype. We determined the prevalence of the 14 known and seven
previously unknown non-G985 mutations in 52 families with MCAD deficiency
not caused by homozygosity for the prevalent G985 mutation. This showed
that none of the non-G985 mutations are prevalent, and led to the
identification of both disease- causing mutations in 14 families in whom
both mutations had not previously been reported. We then evaluated the
severity of the mutations identified in these 14 families. Using expression
of mutant MCAD in Escherichia coli with or without co-overexpression of the
molecular chaperonins GroESL we showed that five of the missense mutations
affect the folding and/or stability of the protein, and that the residual
enzyme activity of some of them could be modulated to a different extent
depending on the amounts of available chaperonins. Thus, some of the
missense mutations may result in relatively high levels of residual enzyme
activity, whereas the mutations leading to premature stop codons will
result in no residual enzyme activity. By correlating the observed types of
mutations identified to the clinical/biochemical data in the 14 patients in
whom we identified both disease-causing mutations, we show that a
genotype/phenotype correlation in MCAD deficiency is not straightforward.
Different mutations may contribute with different susceptibilities for
disease precipitation, when the patient is subjected to metabolic stress,
but other genetic and environmental factors may play an equally important
role.
相似文献
998.
R Nguyen TS Mir L Kluwe K Jett M Kentsch G Mueller H Kehrer‐Sawatzki JM Friedman V‐F Mautner 《Clinical genetics》2013,84(4):344-349
The aim of this study was to characterize cardiac features of patients with neurofibromatosis 1 (NF1) and large deletions of the NF1 gene region. The study participants were 16 patients with large NF1 deletions and 16 age‐ and sex‐matched NF1 patients without such deletions. All the patients were comprehensively characterized clinically and by echocardiography. Six of 16 NF1 deletion patients but none of 16 non‐deletion NF1 patients have major cardiac abnormalities (p = 0.041). Congenital heart defects (CHDs) include mitral insufficiency in two patients and ventricular septal defect, aortic stenosis, and aortic insufficiency in one patient each. Three deletion patients have hypertrophic cardiomyopathy. Two patients have intracardiac tumors. NF1 patients without large deletions have increased left ventricular (LV) diastolic posterior wall thickness (p < 0.001) and increased intraventricular diastolic septal thickness (p = 0.001) compared with a healthy reference population without NF1, suggestive of eccentric LV hypertrophy. CHDs and other cardiovascular anomalies are more frequent among patients with large NF1 deletion and may cause serious clinical complications. Eccentric LV hypertrophy may occur in NF1 patients without whole gene deletions, but the clinical significance of this finding is uncertain. All patients with clinical suspicion for NF1 should be referred to a cardiologist for evaluation and surveillance. 相似文献
999.
Huug J van Duijn Marijke M Kuyvenhoven Franois G Schellevis Theo JM Verheij 《The British journal of general practice》2007,57(540):561-568
BACKGROUND: Although the vast majority of respiratory tract symptoms are self-limiting, many patients visit their GP for these symptoms and antibiotics are over-prescribed. AIM: To explore determinants of patients visiting GPs for recent cough, sore throat, or earache; for being prescribed antibiotics; and for patients' satisfaction with visiting the GP. Design of the study: Second Dutch National Survey of General Practice (DNSGP-2) with a health interview and an additional questionnaire. SETTING: A total of 7057 adult patients of 163 GPs in the Netherlands. METHOD: Characteristics of patients and GPs as well as morbidity data were derived from the DNSGP-2 and a health interview. Characteristics of the symptoms, GPs' management and patients' satisfaction were measured by an additional written questionnaire. Data were analysed by means of multivariate logistic regression. RESULTS: About 40% of the responders (n = 1083) reported cough, sore throat, or earache in the 2 weeks preceding the interview and, of them, 250 visited their GP. Of this latter group, 97 patients were prescribed antibiotics. Apart from non-medical reasons, relevant medical factors played an important role in deciding to visit the GP. Smokers and patients with cardiac disease or diabetes mellitus were not especially inclined to see their GP. Smoking behaviour, fever, and views on respiratory tract symptoms and antibiotics of patients and GPs were associated with being prescribed antibiotics. Patients' perception of having been carefully examined was associated with their satisfaction, while receiving antibiotics was not. CONCLUSION: GPs should inform patients with clear elevated risk when to visit their GP in cases of cough, sore throat, or earache. There is still a need for GPs and patients to be better informed about the limited significance of single inflammation signs (for example, fever and green phlegm) as an indication for antibiotics. Careful examination of the patient contributes to patient satisfaction. 相似文献
1000.
Linda JM Oostendorp Petronella B Ottevanger Winette TA van der Graaf Peep FM Stalmeier 《BMC medical informatics and decision making》2011,11(1):9