1,323 research outputs found
The potential role of T-cells and their interaction with antigen-presenting cells in mediating immunosuppression following trauma-hemorrhage
Objective: Trauma-hemorrhage results in depressed immune responses of antigen-presenting cells (APCs) and T-cells. Recent studies suggest a key role of depressed T-cell derived interferon (IFN)-g in this complex immune cell interaction. The aim of this study was to elucidate further the underlying mechanisms responsible for dysfunctional T-cells and their interaction with APCs following trauma-hemorrhage.
Design: Adult C3H/HeN male mice were subjected to trauma-hemorrhage (3-cm midline laparotomy) followed by hemorrhage (blood pressure of 35�5mmHg for 90 min and resuscitation) or sham operation. At 24 h thereafter, spleens were harvested and T-cells (by Microbeads) and APCs (via adherence) were Isolated. Co-cultures of T-cells and APCs were established for 48 h and stimulated with concanavalin A and lipopolysaccharide. T-Cell specific cytokines known to affect APC function (i.e. interleukin(IL)-2, IL-4 and granulocyte-macrophage colony-stimulating factor (GM-CSF)) were measured in culture supernatants by Multiplex assay. The expression of MHC class II as well as co-stimulatory surface molecules on T-cells and APCs was determined by flow cytometry.
Results: The release of IL-4 and GM-CSF by T-cells was suppressed following trauma-hemorrhage, irrespective of whether sham or trauma-hemorrhage APCs were present. Antigen-presenting cells from animals subjected to trauma-hemorrhage did not affect T-cell derived cytokine release by sham T-cells. In contrast, T-cells from traumahemorrhage animals depressed MHC class II expression of CD11c(þ) cells, irrespective of whether APCs underwent sham or trauma-hemorrhage procedure. Surprisingly, co-stimulatory molecules on APCs (CD80, CD86) were not affected by trauma-hemorrhage.
Conclusions: These results suggest that beside IFN-g other T-cell derived cytokines contribute to immunosuppression following trauma-hemorrhage causing diminished MHC II expression on APCs. Thus, T-cells appear to play an important role in this interaction at the time-point examined. Therapeutic approaches should aim at maintenance of T-cell function and their interaction with APCs to prevent extended immunosuppression following trauma-hemorrhage
Long-term Variability Properties and Periodicity Analysis for Blazars
In this paper, the compiled long-term optical and infrared measurements of
some blazars are used to analyze the variation properties and the optical data
are used to search for periodicity evidence in the lightcurve by means of the
Jurkevich technique and the discrete correlation function (DCF) method.
Following periods are found: 4.52-year for 3C 66A; 1.56 and 2.95 years for AO
0235+164;
14.4, 18.6 years for PKS 0735+178; 17.85 and 24.7 years for PKS 0754+100;
5.53 and 11.75 for OJ 287. 4.45, and 6.89 years for PKS 1215; 9 and 14.84 years
for PKS 1219+285;
2.0, 13.5 and 22.5 for 3C273; 7.1 year for 3C279;
6.07 for PKS 1308+326; 3.0 and 16.5 years for PKS 1418+546;
2.0 and 9.35 years for PKS 1514-241; 18.18 for PKS 1807+698;
4.16 and 7.0 for 2155-304; 14 and 20 years for BL Lacertae. Some explanations
have been discussed.Comment: 10 pages, 2 table, no figure, a proceeding paper for Pacific Rim
Conference on Stellar Astrophysics, Aug. 1999, HongKong, Chin
Anti-Allergic Cromones Inhibit Histamine and Eicosanoid Release from Activated Human and Murine Mast Cells by Releasing Annexin A1
PMCID: PMC3601088This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Search for new phenomena in final states with an energetic jet and large missing transverse momentum in pp collisions at √ s = 8 TeV with the ATLAS detector
Results of a search for new phenomena in final states with an energetic jet and large missing transverse momentum are reported. The search uses 20.3 fb−1 of √ s = 8 TeV data collected in 2012 with the ATLAS detector at the LHC. Events are required to have at least one jet with pT > 120 GeV and no leptons. Nine signal regions are considered with increasing missing transverse momentum requirements between Emiss T > 150 GeV and Emiss T > 700 GeV. Good agreement is observed between the number of events in data and Standard Model expectations. The results are translated into exclusion limits on models with either large extra spatial dimensions, pair production of weakly interacting dark matter candidates, or production of very light gravitinos in a gauge-mediated supersymmetric model. In addition, limits on the production of an invisibly decaying Higgs-like boson leading to similar topologies in the final state are presente
The Immunomodulatory Role of Adjuvants in Vaccines Formulated with the Recombinant Antigens Ov-103 and Ov-RAL-2 against Onchocerca volvulus in Mice.
BACKGROUND: In some regions in Africa, elimination of onchocerciasis may be possible with mass drug administration, although there is concern based on several factors that onchocerciasis cannot be eliminated solely through this approach. A vaccine against Onchocerca volvulus would provide a critical tool for the ultimate elimination of this infection. Previous studies have demonstrated that immunization of mice with Ov-103 and Ov-RAL-2, when formulated with alum, induced protective immunity. It was hypothesized that the levels of protective immunity induced with the two recombinant antigens formulated with alum would be improved by formulation with other adjuvants known to enhance different types of antigen-specific immune responses.
METHODOLOGY/ PRINCIPAL FINDINGS: Immunizing mice with Ov-103 and Ov-RAL-2 in conjunction with alum, Advax 2 and MF59 induced significant levels of larval killing and host protection. The immune response was biased towards Th2 with all three of the adjuvants, with IgG1 the dominant antibody. Improved larval killing and host protection was observed in mice immunized with co-administered Ov-103 and Ov-RAL-2 in conjunction with each of the three adjuvants as compared to single immunizations. Antigen-specific antibody titers were significantly increased in mice immunized concurrently with the two antigens. Based on chemokine levels, it appears that neutrophils and eosinophils participate in the protective immune response induced by Ov-103, and macrophages and neutrophils participate in immunity induced by Ov-RAL-2.
CONCLUSIONS/SIGNIFICANCE: The mechanism of protective immunity induced by Ov-103 and Ov-RAL-2, with the adjuvants alum, Advax 2 and MF59, appears to be multifactorial with roles for cytokines, chemokines, antibody and specific effector cells. The vaccines developed in this study have the potential of reducing the morbidity associated with onchocerciasis in humans
Neuropathic Pain in Rats with a Partial Sciatic Nerve Ligation Is Alleviated by Intravenous Injection of Monoclonal Antibody to High Mobility Group Box-1
High mobility group box-1 (HMGB1) is associated with the pathogenesis of inflammatory diseases. A previous study reported that intravenous injection of anti-HMGB1 monoclonal antibody significantly attenuated brain edema in a rat model of stroke, possibly by attenuating glial activation. Peripheral nerve injury leads to increased activity of glia in the spinal cord dorsal horn. Thus, it is possible that the anti-HMGB1 antibody could also be efficacious in attenuating peripheral nerve injury-induced pain. Following partial sciatic nerve ligation (PSNL), rats were treated with either anti-HMGB1 or control IgG. Intravenous treatment with anti-HMGB1 monoclonal antibody (2 mg/kg) significantly ameliorated PSNL-induced hind paw tactile hypersensitivity at 7, 14 and 21 days, but not 3 days, after ligation, whereas control IgG had no effect on tactile hypersensitivity. The expression of HMGB1 protein in the spinal dorsal horn was significantly increased 7, 14 and 21 days after PSNL; the efficacy of the anti-HMGB1 antibody is likely related to the presence of HMGB1 protein. Also, the injury-induced translocation of HMGB1 from the nucleus to the cytosol occurred mainly in dorsal horn neurons and not in astrocytes and microglia, indicating a neuronal source of HMGB1. Markers of astrocyte (glial fibrillary acidic protein (GFAP)), microglia (ionized calcium binding adaptor molecule 1 (Iba1)) and spinal neuron (cFos) activity were greatly increased in the ipsilateral dorsal horn side compared to the sham-operated side 21 days after PSNL. Anti-HMGB1 monoclonal antibody treatment significantly decreased the injury-induced expression of cFos and Iba1, but not GFAP. The results demonstrate that nerve injury evokes the synthesis and release of HMGB1 from spinal neurons, facilitating the activity of both microglia and neurons, which in turn leads to symptoms of neuropathic pain. Thus, the targeting of HMGB1 could be a useful therapeutic strategy in the treatment of chronic pain
How to increase earthquake and home fire preparedness: the fix-it intervention
Published, evaluated community intervention studies concerning natural hazard preparedness are rare. Most lack a rigorous methodology, thereby hampering the development of evidence-based interventions. This paper describes the rationale and methodology of a cross-cultural, longitudinal intervention study on earthquake and home fire preparedness, termed fix-it. The aim is to evaluate whether and how the intervention brings about behaviour change in the targeted communities in two coastal cities with high seismic risk: Seattle, USA and Izmir, Turkey. Participants are adult residents of these cities. The intervention group attends a 6-h workshop, which focuses on securing items in the household. The control group does not attend the workshop. All participants complete baseline and post-intervention, as well as 3- and 12-month follow-up assessments. The primary outcome measure is an observational measure of nine preparedness items for earthquake and fire in participants’ homes. This is evaluated alongside participants’ self-reports concerning their preparedness levels. Secondary outcomes are changes in levels of self-efficacy, perceived outcome, trust, corruption, empowerment, anxiety and social cohesion. Results from the first of the studies, conducted in Seattle in September 2015, indicate that while the fix-it intervention is effective, in the longer term, multi-hazard preparedness is increased by the mere act of going into people’s homes to observe their preparedness levels along with assessing self-reported preparedness and sociopsychological orientation towards natural hazards. This protocol and study aim to augment the empirical literature on natural hazard preparedness, informing national and international policy on delivery of evidence-based community interventions to promote multi-hazard preparedness in households
Quality of life and eating disorders: a systematic review
This article provides a systematic review of articles on quality of life (QoL) among individuals with eating disorders. A literature search was conducted using six databases. Manual searches were also performed in two specialized journals, covering the period from January 1975 to June 2008. The search strategies identified a total of 29,537 articles. Forty-one studies met the inclusion criteria, and 36 were analyzed in the present review. Patients with eating disorders showed reduced QoL as compared to normal controls and individuals with other psychiatric disorders. The mental health component of QoL showed greater impairment than the physical component. Patients with binge eating disorders showed reduced physical and psychological QoL. We identified few studies on QoL in bulimia nervosa-only patients. QoL assessment of anorexia nervosa patients showed a modest impact on the physical domain. However, this finding should be interpreted with caution, since it may be due to an artifact in the disorder's psychopathology rather than better health status per se.O objetivo foi fazer uma revisão sistemática dos estudos que avaliam qualidade de vida em pessoas com transtornos alimentares. Foram realizadas buscas bibliográficas em seis bases de dados e buscas manuais em duas revistas, abrangendo o período de janeiro de 1975 até junho de 2008. As estratégias de busca forneceram um total de 29.537 referências. Quarenta e um estudos preencheram os critérios de inclusão desta revisão e 36 foram analisados no presente trabalho. De modo geral, os estudos revelam prejuízos na qualidade de vida de pacientes com transtornos alimentares quando comparados a grupos normais ou outras patologias psiquiátricas. O aspecto mental da qualidade de vida mostra-se mais prejudicado. A avaliação da qualidade de vida em sujeitos com transtorno da compulsão alimentar periódica revela prejuízos nos aspectos físico e mental da qualidade de vida. Há pouca evidência e discussão para indivíduos com bulimia nervosa isoladamente. Em sujeitos com anorexia nervosa, a avaliação requer cautela, já que o aparente menor impacto físico pode ser reflexo da psicopatologia específica deste transtorno e não do funcionamento saudável.Universidade Federal de São Paulo (UNIFESP) Escola Paulista de MedicinaUNIFESP, EPMSciEL
The role of peer physical activity champions in the workplace: a qualitative study
Aims: Peer health champions are suggested as an important component of multilevel workplace interventions to promote healthy behaviours such as physical activity. There is accumulating quantitative evidence of their effectiveness but as yet little exploration of why and how champions influence the behaviour of their peers. The current study explores the role of peer physical activity champions (PPACs) in influencing colleagues’ physical activity behaviour from the perspectives of both champions and colleagues.
Methods: Seven months after the introduction of a workplace physical activity programme in 17 small and medium sized enterprices (SMEs) two focus groups were held with PPACs and four with programme participants. Focus groups were semi-structured and topics covered included: the influence of PPACs and other colleagues on their physical activity, characteristics of an effective PPAC and feelings about the PPAC role. Data were analysed using inductive thematic analysis.
Results: Three overarching themes emerged: how PPACs encourage physical activity; valuable PPAC characteristics; and sustaining motivation for the PPAC role. Both direct encouragement from PPACs and facilitation of wider physical activity supportive social networks within the workplace encouraged behaviour change. Physical activity behaviour change is a delicate subject and it was important that PPACs provided enthusiastic and persistent encouragement without seeming judgemental. Being a physical activity role model was also a valuable characteristic. The PPACs found it satisfying to see positive changes in their colleagues who had become more active. However, colleagues often did not engage in suggested activities and PPACs required resilience to maintain personal motivation for the role despite this.
Conclusions:
The results indicate that it is feasible to incorporate PPACs into SME based physical activity interventions. Given the importance that participants attached to feeling part of a group of individuals with a common aim of increasing their physical activity, it is recommended that PPAC training includes suggestions for facilitating social connections between colleagues. Sensitivity is required when initiating and engaging in conversations with colleagues about increasing their physical activity and therefore brief motivational interviewing training may be helpful for PPACs. Programmes should ensure PPACs themselves are provided with social support, especially from others in the same role, to help sustain motivation for their role. These findings will be useful to health-promotion professionals developing workplace health programmes. Future research should explore the processes by which peer health champions facilitate changes in a range of health behaviours to identify common and behaviour specific recommendations
Pathogenesis of progressive scarring trachoma in Ethiopia and Tanzania and its implications for disease control: two cohort studies.
BACKGROUND: Trachoma causes blindness through a conjunctival scarring process initiated by ocular Chlamydia trachomatis infection; however, the rates, drivers and pathophysiological determinants are poorly understood. We investigated progressive scarring and its relationship to conjunctival infection, inflammation and transcript levels of cytokines and fibrogenic factors. METHODOLOGY/PRINCIPAL FINDINGS: We recruited two cohorts, one each in Ethiopia and Tanzania, of individuals with established trachomatous conjunctival scarring. They were followed six-monthly for two years, with clinical examinations and conjunctival swab sample collection. Progressive scarring cases were identified by comparing baseline and two-year photographs, and compared to individuals without progression. Samples were tested for C. trachomatis by PCR and transcript levels of S100A7, IL1B, IL13, IL17A, CXCL5, CTGF, SPARCL1, CEACAM5, MMP7, MMP9 and CD83 were estimated by quantitative RT-PCR. Progressive scarring was found in 135/585 (23.1%) of Ethiopian participants and 173/577 (30.0%) of Tanzanian participants. There was a strong relationship between progressive scarring and increasing inflammatory episodes (Ethiopia: OR 5.93, 95%CI 3.31-10.6, p<0.0001. Tanzania: OR 5.76, 95%CI 2.60-12.7, p<0.0001). No episodes of C. trachomatis infection were detected in the Ethiopian cohort and only 5 episodes in the Tanzanian cohort. Clinical inflammation, but not scarring progression, was associated with increased expression of S100A7, IL1B, IL17A, CXCL5, CTGF, CEACAM5, MMP7, CD83 and reduced SPARCL1. CONCLUSIONS/SIGNIFICANCE: Scarring progressed in the absence of detectable C. trachomatis, which raises uncertainty about the primary drivers of late-stage trachoma. Chronic conjunctival inflammation appears to be central and is associated with enriched expression of pro-inflammatory factors and altered expression of extracellular matrix regulators. Host determinants of scarring progression appear more complex and subtle than the features of inflammation. Overall this indicates a potential role for anti-inflammatory interventions to interrupt progression and the need for trichiasis disease surveillance and surgery long after chlamydial infection has been controlled at community level
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