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101.
Françoise Farace Anne-Marie Le Ridant Bernard Escudier Thierry Hercend Frédéric Triebel 《Biotherapy》1992,5(1):11-20
We have attempted to improve negative selection procedures for the large scale purification of human CD
in3
–
CD56+ NK cells. In a series of experiments, purifications of NK cells from 108 PBMC were performed by T cell depletion using either direct or indirect anti-CD3 labeling and the Magnetic Activated Cell Separation (MACS) procedure. Contaminating CD3+ cells were still present using either one of these two different T cell depletion protocols as shown by phenotyping IL-2 supplemented cell cultures on day 12. A second cycle of purification was therefore added. When MACS and Dynabeads were compared as complementary procedures to the first MACS cycle starting with 108 cells, the Dynabeads method was found to be superior to the MACS with regard to the elimination of residual T cells. Starting from 109 PBMC, we showed that this MACS+Dynabeads procedure gave similar satisfactory results when compared to the scaling-up of a previously established two steps procedure using Dynabeads. These two approaches (MACS+Dynabeads and 2 cycles of Dynabeads) have been also tested in a clinical setting to purify NK cells from cancer patients prior toin vitro expansion. The results indicate that the two methods are equivalent with respect to purity and recovery rate; a slight advantage in terms of feasibility was found in favor of 2 cycles of Dynabeads. 相似文献
102.
103.
Karin A. W. Wadt Lauren G. Aoude Lotte Krogh Lone Sunde Anders Bojesen Karen Gr?nskov Nine Wartacz Jakob Ek Morten Tolstrup-Andersen Mette Klarskov-Andersen ?ke Borg Steffen Heegaard Jens F. Kiilgaard Thomas V. O. Hansen Kerenaftali Klein G?ran J?nsson Krzysztof T. Drzewiecki Morten Dun? Nicholas K. Hayward Anne-Marie Gerdes 《PloS one》2015,10(3)
Both environmental and host factors influence risk of cutaneous
melanoma (CM), and worldwide, the incidence varies depending on constitutional determinants of skin type and pigmentation, latitude, and patterns of sun exposure. We performed genetic analysis of CDKN2A, CDK4, BAP1, MC1R, and MITFp.E318K in Danish high-risk melanoma cases and found CDKN2A germline mutations in 11.3% of CM families with three or more affected individuals, including four previously undescribed mutations. Rare mutations were also seen in CDK4 and BAP1, while MC1R variants were common, occurring at more than twice the frequency compared to Danish controls. The MITF p.E318K variant similarly occurred at an approximately three-fold higher frequency in melanoma cases than controls. To conclude, we propose that mutation screening of CDKN2A and CDK4 in Denmark should predominantly be performed in families with at least 3 cases of CM. In addition, we recommend that testing of BAP1 should not be conducted routinely in CM families but should be reserved for families with CM and uveal melanoma, or mesothelioma. 相似文献
104.
Objective
Although people with disabilities have great potential to provide advantages to work environments, many encounter barriers in finding employment, especially youth who are looking for their first job. A job interview is an essential component of obtaining employment. The objective of this study is to explore the content of the answers given in job interviews among youth with disabilities compared to typically developing youth.Methods
A purposive sample of 31 youth (16 with typical development and 15 with disability) completed a mock job interview as part of an employment readiness study. The interview questions focused on skills and experiences, areas for improvement, and actions taken during problem-based scenarios. Transcribed interviews were analyzed using a content analysis of themes that emerged from the interviews.Results
We found several similarities and differences between youth with disabilities and typically developing youth. Similarities included giving examples from school, emphasizing their “soft skills” (i.e., people and communication skills) and giving examples of relevant experience for the position. Both groups of youth gave similar examples for something they were proud of but fewer youth with disabilities provided examples. Differences in the content of job interview answers between the two groups included youth with disabilities: (1) disclosing their condition; (2) giving fewer examples related to customer service and teamwork skills; (3) experiencing greater challenges in providing feedback to team members and responding to scenario-based problem solving questions; and (4) drawing on examples from past work, volunteer and extra curricular activities.Conclusions
Clinicians and educators should help youth to understand what their marketable skills are and how to highlight them in an interview. Employers need to understand that the experiences of youth with disabilities may be different than typically developing youth. Our findings also help to inform employment readiness programs by highlighting the areas where youth with disabilities may need extra help as compared to typically developing youth. 相似文献105.
Brigitte Lefebvre Simon Lévesque Anne-Marie Bourgault Michael R. Mulvey Laura Mataseje David Boyd Florence Doualla-Bell Cécile Tremblay 《PloS one》2015,10(4)
The emergence and spread of carbapenemase-producing Enterobacteriaceae (CPE) represent a major public health concern because these bacteria are usually extensively resistant to most antibiotics. In order to evaluate their dissemination in Quebec, a surveillance program was introduced in 2010. We report the molecular and epidemiological profiles of CPE isolates collected. Between August 2010 and December 2012, a total of 742 non-duplicate isolates non-susceptible to carbapenems were analysed. AmpC β-lactamase and metallo-β-lactamase production were detected by Etest and carbapenemase production by the modified Hodge test (MHT). Antibiotic susceptibility profiles were determined using broth microdilution or Etest. Clonality of Klebsiella pneumoniae carbapenemase (KPC) strains was analyzed by pulsed-field gel electrophoresis (PFGE). The presence of genes encoding carbapenemases as well as other β-lactamases was detected using PCR. Of the 742 isolates tested, 169 (22.8%) were CPE. Of these 169 isolates, 151 (89.3%) harboured a bla
KPC gene while the remaining isolates carried bla
SME (n = 9), bla
OXA-48 (n = 5), bla
NDM (n = 3), and bla
NMC (n = 1) genes. Among the 93 KPC strains presenting with a unique pattern (unique PFGE pattern and/or unique antibiotics susceptibility profile), 99% were resistant to ertapenem, 95% to imipenem, 87% to meropenem, 97% to aztreonam, 31% to colistin and 2% to tigecycline. In 19 patients, 2 to 5 KPC strains from different species or with a different PFGE pattern were isolated. CPE strains were present in the province of Quebec with the majority of strains harbouring KPC. Alternately, SME, OXA-48 and NMC containing strains were rarely found. 相似文献
106.
The cognitive profile and measured intellectual level vary according to assessment tools in children on the autism spectrum, much more so than in typically developing children. The recent inclusion of intellectual functioning in the diagnostic process for autism spectrum disorders leads to the crucial question on how to assess intelligence in autism, especially as some tests and subtests seem more sensitive to certain neurodevelopmental conditions. Our first aim was to examine the cognitive profile on the current version of the most widely used test, the Wechsler Intelligence Scales for Children (WISC-IV), for a homogenous subgroup of children on the autism spectrum, i.e. corresponding to DSM-IV diagnosis of “autism”. The second aim was to compare cognitive profiles obtained on the third edition versus 4th edition of WISC, in order to verify whether the WISC-IV yields a more distinctive cognitive profile in autistic children. The third aim was to examine the impact of the WISC-IV on the cognitive profile of another subgroup, children with Asperger’s Syndrome. 51 autistic, 15 Asperger and 42 typically developing children completed the WISC-IV and were individually matched to children who completed the WISC-III. Divergent WISC-IV profiles were observed despite no significant intelligence quotient difference between groups. Autistic children scored significantly higher on the Perceptual Reasoning Index than on the Verbal Comprehension Index, a discrepancy that nearly tripled in comparison to WISC-III results. Asperger children scored higher on the VCI than on other indexes, with the lowest score found on the Processing Speed Index. WISC-IV cognitive profiles were consistent with, but more pronounced than WISC-III profiles. Cognitive profiles are a valuable diagnostic tool for differential diagnosis, keeping in mind that children on the autism spectrum might be more sensitive to the choice of subtests used to assess intelligence. 相似文献
107.
Jannik Langtved Pallisgaard Tommi Bo Lindhardt Morten Lock Hansen Anne-Marie Schjerning Jonas Bjerring Olesen Laila Staerk Christian Torp-Pedersen Gunnar Hilmar Gislason 《PloS one》2015,10(10)
Aim
Cardioversion can rapidly and effectively restore sinus rhythm in patients with persistent atrial fibrillation. Since 2011 dabigatran has been available as an alternative to warfarin to prevent thromboembolic events in patients with non-valvular atrial fibrillation undergoing cardioversion. We studied time to cardioversion, risk of adverse events, and risk of readmission with atrial fibrillation after cardioversion according to anticoagulation therapy.Methods and Results
Through the nationwide Danish registries we included 1,230 oral anticoagulation naïve patients with first time non-valvular atrial fibrillation and first time cardioversion from 2011 to 2012; 37% in the dabigatran group (n = 456), and 63% in the warfarin group (n = 774). Median time to cardioversion was 4.0 (interquartile range [IQR] 2.9 to 6.5) and 6.9 (IQR 3.9 to 12.1) weeks in the dabigatran and warfarin groups respectively, and the adjusted odds ratio of cardioversion within the first 4 weeks was 2.3 (95% confidence interval [CI] 1.7 to 3.1) in favor of dabigatran. The cumulative incidence of composite endpoint of stroke, bleeding or death were 2.0% and 1.0% at 30 weeks in the warfarin and dabigatran groups respectively, with an adjusted hazard ratio of 1.33 (95% CI 0.33 to 5.42). Cumulative incidence of readmission with atrial fibrillation after 30 weeks were 9% and 11% in the warfarin and dabigatran groups, respectively, and an adjusted hazard ratio of 0.66 (95% CI 0.41 to 1.08).Conclusion
Anticoagulation treatment with dabigatran allows shorter time to cardioversion for atrial fibrillation than warfarin, and appears to be an effective and safe alternative treatment strategy to warfarin. 相似文献108.
Isabelle Cloutier Catherine Paradis-Bleau Anne-Marie Giroux Xavier Pigeon Marjolaine Arseneault Roger C. Levesque Michèle Auger 《European biophysics journal : EBJ》2010,39(2):263-276
The use of naturally occurring lytic bacteriophage proteins as specific antibacterial agents is a promising way to treat bacterial
infections caused by antibiotic-resistant pathogens. The opportunity to develop bacterial resistance to these agents is minimized
by their broad mechanism of action on bacterial membranes and peptidoglycan integrity. In the present study, we have investigated
lipid interactions of the gp144 lytic transglycosylase from the Pseudomonas aeruginosa phage ϕKZ. Interactions with zwitterionic lipids characteristic of eukaryotic cells and with anionic lipids characteristic
of bacterial cells were studied using fluorescence, solid-state nuclear magnetic resonance, Fourier transform infrared, circular
dichroism, Langmuir monolayers, and Brewster angle microscopy (BAM). Gp144 interacted preferentially with anionic lipids,
and the presence of gp144 in anionic model systems induced membrane disruption and lysis. Lipid domain formation in anionic
membranes was observed by BAM. Gp144 did not induce disruption of zwitterionic membranes but caused an increase in rigidity
of the lipid polar head group. However, gp144 interacted with zwitterionic and anionic lipids in a model membrane system containing
both lipids. Finally, the gp144 secondary structure was not significantly modified upon lipid binding. 相似文献
109.
Susanne Ström Frida Holm Rosita Bergström Anne-Marie Strömberg Outi Hovatta 《In vitro cellular & developmental biology. Animal》2010,46(3-4):337-344
We have derived 30 human embryonic stem cell lines from supernumerary blastocysts in our laboratory. During the derivation process, we have studied new and safe method to establish good quality lines. All our human embryonic stem cell lines have been derived using human foreskin fibroblasts as feeder cells. The 26 more recent lines were derived in a medium containing serum replacement instead of fetal calf serum. Mechanical isolation of the inner cell mass using flexible metal needles was used in deriving the 10 latest lines. The lines are karyotypically normal, but culture adaptation in two lines has been observed. Our human embryonic stem cell lines are banked, and they are available for researchers. 相似文献
110.
Véronique Dubois Anne-Marie Lambeir Stefaan Vandamme Veerle Matheeussen Yves Guisez Simon Scharpé Ingrid De Meester 《Biochimica et Biophysica Acta - Proteins and Proteomics》2010,1804(4):781-788
The dipeptidyl peptidases (DPP) 8 and 9 belong to the DPP4 activity and/or structure homologues (DASH). Recently, a DPP9-like protein was purified from bovine testes. The aim of the present study was to prove its identity and to investigate the characteristics of this natural enzyme. We report the identification and N-terminal sequence analysis by MALDI-TOF/TOF MS, of the purified bovine enzyme as DPP9. The tryptic peptides after in-gel digestion covered 41% and 38% of the short and full-length variants of bovine DPP9, respectively. Using Asp-N digestion combined with a very recently described mass spectrometric method using DITC glass beads, the N-terminal peptide (XTGALTSERG) was isolated. It corresponds to the N-terminus of the short form of bovine DPP9. There was no evidence for glycosylation of purified bovine DPP9. The purified DPP9 was activated and stabilized by DTT. Bovine DPP9 lost its activity almost completely after alkylation with N-ethylmaleimide. Also alkylation with iodoacetamide inhibited DPP9, albeit only 70%. Other properties of bovine DPP9 are reported, including functional stability and sensitivity towards metal ions. Our results indicate that the short form of DPP9 can be isolated from bovine testes and that it behaves as a stable enzyme suitable for further functional and biochemical characterization as well as for inhibitor screening and characterization. 相似文献