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41.
Characterization of terminal NeuNAcalpha2-3Galbeta1-4GlcNAc sequence in lipooligosaccharides of Neisseria meningitidis 总被引:1,自引:0,他引:1
Group B and C Neisseria meningitidis are the major cause of meningococcal
disease in the United States and in Europe. N . meningitidis
lipooligosaccharide (LOS), a major surface antigen, can be divided into 12
immunotypes of which L1 through L8 were found among Group B and C
organisms. Groups B and C but not Group A may sialylate their LOSs with
N-acetylneuraminic acid (NeuNAc) at the nonreducing end because they
synthesize CMP-NeuNAc. Using sialic acid-galactose binding lectins as
probes in an ELISA format, six of the eight LOS immunotypes (L2, L3, L4,
L5, L7, and L8) in Groups B and C bound specifically to Maackia amurensis
leukoagglutinin (MAL), which recognizes NeuNAcalpha2- 3Galbeta1-4GlcNAc/Glc
sequence, but not to Sambucus nigra agglutinin, which binds
NeuNAcalpha2-6Gal sequence. The combination of SDS-PAGE and MAL-blot
analyses revealed that these six LOSs contained only the
NeuNAcalpha2-3Galbeta1-4GlcNAc trisaccharide sequence in their 4.1 kDa LOS
components, which have a common terminal lacto-N-neotetraose (LNnT,
Galbeta1-4GlcNAcbeta1-3Galbeta1-4Glc) structure when nonsialylated as shown
by previous studies. The LOS-lectin binding was abolished when the LOSs
were treated with Newcastle disease viral neuraminidase which cleaves
alpha2-->3 linked sialic acid. Methylation analysis of a representative
LOS (L2) confirmed that NeuNAc is 2-->3 linked to Gal. Thus, these LOSs
structurally mimic certain glycolipids, i.e., paragloboside (LNnT-ceramide)
and sialylparagloboside and some glycoproteins in having LNnT and
N-acetyllactosamine sequences, respectively, with or without alpha2-->3
linked NeuNAc. The molecular mimicry of the LOSs may play a role in the
pathogenesis of N.meningitidis by assisting the organism to evade host
immune defenses in man.
相似文献
42.
43.
Samar M. Aoun Gunn Grande Denise Howting Kathleen Deas Chris Toye Lakkhina Troeung Kelli Stajduhar Gail Ewing 《PloS one》2015,10(4)
Family caregiving towards the end-of-life entails considerable emotional, social, financial and physical costs for caregivers. Evidence suggests that good support can improve caregiver psychological outcomes. The primary aim of this study was to investigate the impact of using the carer support needs assessment tool (CSNAT), as an intervention to identify and address support needs in end of life home care, on family caregiver outcomes. A stepped wedge design was used to trial the CSNAT intervention in three bases of Silver Chain Hospice Care in Western Australia, 2012-14. The intervention consisted of at least two visits from nurses (2-3 weeks apart) to identify, review and address caregivers’ needs. The outcome measures for the intervention and control groups were caregiver strain and distress as measured by the Family Appraisal of Caregiving Questionnaire (FACQ-PC), caregiver mental and physical health as measured by SF-12v2, and caregiver workload as measured by extent of caregiver assistance with activities of daily living, at baseline and follow up. Total recruitment was 620. There was 45% attrition for each group between baseline and follow-up mainly due to patient deaths resulting in 322 caregivers completing the study (233 in the intervention group and 89 in the control group). At follow-up, the intervention group showed significant reduction in caregiver strain relative to controls, p=0.018, d=0.348 (95% CI 0.25 to 0.41). Priority support needs identified by caregivers included knowing what to expect in the future, having time for yourself in the day and dealing with your feelings and worries. Despite the challenges at the clinician, organisational and trial levels, the CSNAT intervention led to an improvement in caregiver strain. Effective implementation of an evidence-informed and caregiver-led tool represents a necessary step towards helping palliative care providers better assess and address caregiver needs, ensuring adequate family caregiver support and reduction in caregiver strain. 相似文献
44.
Charlotte ?ngstr?m-Br?nnstr?m Gunn Engvall Tara Mullaney Kristina Nilsson Gun Wickart-Johansson Anna-Maja Sv?rd Tufve Nyholm Jack Lindh Viveca Lindh 《PloS one》2015,10(10)
Approximately 300 children, from 0 to 18 years old, are diagnosed with cancer in Sweden every year. Of these children, 80–90 of them undergo radiotherapy treatment for their cancer. Although radiotherapy is an encounter with advanced technology, few studies have investigated the child’s and the parent’s view of the procedure. As part of an ongoing multicenter study aimed to improve patient preparation and the care environment in pediatric radiotherapy, this article reports the findings from interviews with parents at baseline. The aim of the present study was twofold: to describe parents’ experience when their child undergoes radiotherapy treatment, and to report parents’ suggestions for improvements during radiotherapy for their children. Sixteen mothers and sixteen fathers of children between 2–16 years old with various cancer diagnoses were interviewed. Data were analyzed using content analysis. The findings showed that cancer and treatment turns people’s lives upside down, affecting the entire family. Further, the parents experience the child’s suffering and must cope with intense feelings. Radiotherapy treatment includes preparation by skilled and empathetic staff. The parents gradually find that they can deal with the process; and lastly, parents have suggestions for improvements during the radiotherapy treatment. An overarching theme emerged: that despair gradually turns to a sense of security, with a sustained focus on and close interaction with the child. In conclusion, an extreme burden was experienced around the start of radiotherapy, though parents gradually coped with the process. 相似文献
45.
PEX5 acts as a cycling receptor for import of PTS1 proteins into peroxisomes and as a co-receptor for PEX7, the PTS2 receptor, but the mechanism of cargo unloading has remained obscure. Using recombinant protein domains we show PEX5 binding to the PEX14N-terminal domain (PEX14N) has no effect on the affinity of PEX5 for a PTS1 containing peptide. PEX5 can form a complex containing both recombinant PTS1 cargo and endogenous PEX7-thiolase simultaneously but isolation of the complex via the PEX14 construct resulted in an absence of thiolase, suggesting a possible role for PEX14 in the unloading of PTS2 cargos. 相似文献
46.
We investigated the role of the main olfactory and accessory olfactory systems (MOS and AOS respectively) in the detection of androstenone. We used the following experimental approaches: behavioral, surgical removal of the vomeronasal organ (VNX) followed by histochemical verification and Fos immunohistochemistry. Using a Y-maze paradigm we estimated sensitivity of NZB/B1NJ and CBA/J mice to androstenone. CBA mice were 2,000-fold more sensitive to androstenone than NZB mice. VNX caused a 4- to 16-fold decre... 相似文献
47.
Assessing and reporting heterogeneity in treatment effects in clinical trials: a proposal 总被引:1,自引:0,他引:1
David M Kent Peter M Rothwell John PA Ioannidis Doug G Altman Rodney A Hayward 《Trials》2010,11(1):1-11
Background
This paper presents the study protocol for a pragmatic randomised controlled trial to evaluate the impact of a school based program developed to prevent teenage pregnancy. The program includes students taking care of an Infant Simulator; despite growing popularity and an increasing global presence of such programs, there is no published evidence of their long-term impact. The aim of this trial is to evaluate the Virtual Infant Parenting (VIP) program by investigating pre-conceptual health and risk behaviours, teen pregnancy and the resultant birth outcomes, early child health and maternal health.Methods and Design
Fifty-seven schools (86% of 66 eligible secondary schools) in Perth, Australia were recruited to the clustered (by school) randomised trial, with even randomisation to the intervention and control arms. Between 2003 and 2006, the VIP program was administered to 1,267 participants in the intervention schools, while 1,567 participants in the non-intervention schools received standard curriculum. Participants were all female and aged between 13-15 years upon recruitment. Pre and post-intervention questionnaires measured short-term impact and participants are now being followed through their teenage years via data linkage to hospital medical records, abortion clinics and education records. Participants who have a live birth are interviewed by face-to-face interview. Kaplan-Meier survival analysis and proportional hazards regression will test for differences in pregnancy, birth and abortion rates during the teenage years between the study arms.Discussion
This protocol paper provides a detailed overview of the trial design as well as initial results in the form of participant flow. The authors describe the intervention and its delivery within the natural school setting and discuss the practical issues in the conduct of the trial, including recruitment. The trial is pragmatic and will directly inform those who provide Infant Simulator based programs in school settings.Trial registration
ISRCTN24952438 相似文献48.
49.
Caroline PA de Haan Rauni I Kivistö Marjaana Hakkinen Jukka Corander Marja-Liisa Hänninen 《BMC microbiology》2010,10(1):200
Background
Campylobacter jejuni is the most common bacterial cause of human gastroenteritis worldwide. Due to the sporadic nature of infection, sources often remain unknown. Multilocus sequence typing (MLST) has been successfully applied to population genetics of Campylobacter jejuni and mathematical modelling can be applied to the sequence data. Here, we analysed the population structure of a total of 250 Finnish C. jejuni isolates from bovines, poultry meat and humans collected in 2003 using a combination of Bayesian clustering (BAPS software) and phylogenetic analysis. 相似文献50.
L. Lgdberg E. Kaplan M. Drelich E. Harfeldt H. Gunn P. Ehrlich D. Dottavio P. Lake L.
stberg 《Journal of medical primatology》1994,23(5):285-297
The feasibility to raise nonhuman primate antibodies against selected components of the human immune system was tested. The immunogens were whole cells (human T lymphocytes) or purified, recombinant human proteins (cytokines: TNFα or GM-CSF; soluble forms of cell surface antigens: sCD4 or sCD25). Significant immunizations, yielding functionally relevant antibodies, were readily achieved in rhesus monkeys, but, not surprisingly, may be less frequent in chimpanzees. The results suggest a general strategy for production of therapeutically useful MAB. 相似文献