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1.
Nanomedicine ; 10(6): 1287-99, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24607938

RESUMEN

Carbon nanotubes (CNTs) have promised a range of applications in biomedicine. Although influenced by the dispersants used, CNTs are recognized by the innate immune system, predominantly by the classical pathway of the complement system. Here, we confirm that complement activation by the CNT used continues up to C3 and C5, indicating that the entire complement system is activated including the formation of membrane-attack complexes. Using recombinant forms of the globular regions of human C1q (gC1q) as inhibitors of CNT-mediated classical pathway activation, we show that C1q, the first recognition subcomponent of the classical pathway, binds CNTs via the gC1q domain. Complement opsonisation of CNTs significantly enhances their uptake by U937 cells, with concomitant downregulation of pro-inflammatory cytokines and up-regulation of anti-inflammatory cytokines in both U937 cells and human monocytes. We propose that CNT-mediated complement activation may cause recruitment of cellular infiltration, followed by phagocytosis without inducing a pro-inflammatory immune response. FROM THE CLINICAL EDITOR: This study highlights the importance of the complement system in response to carbon nanontube administration, suggesting that the ensuing complement activation may cause recruitment of cellular infiltration, followed by phagocytosis without inducing a pro-inflammatory immune response.


Asunto(s)
Activación de Complemento/efectos de los fármacos , Macrófagos/efectos de los fármacos , Nanotubos de Carbono/toxicidad , Fagocitosis/efectos de los fármacos , Línea Celular , Complemento C1q/inmunología , Citocinas/inmunología , Humanos , Macrófagos/inmunología , Nanotubos de Carbono/ultraestructura
2.
Prev Sci ; 15(6): 879-87, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24122481

RESUMEN

Although cyberbullying is characterized by worrying prevalence rates and associated with a broad range of detrimental consequences, there is a lack of scientifically based and evaluated preventive strategies. Therefore, the present study introduces a theory-based cyberbullying prevention program (Media Heroes; German original: Medienhelden) and evaluates its effectiveness. In a pretest-posttest design (9-month interval), schools were asked to randomly assign their participating classes to either control or intervention group. Longitudinal data were available from 593 middle school students (M Age = 13.3 years, 53 % girls) out of 35 classes, who provided information on cyberbullying behavior as well as socio-demographic and psychosocial variables. While the present results revealed worrying prevalence rates of cyberbullying in middle school, multilevel analyses clearly demonstrate the program's effectiveness in reducing cyberbullying behavior within intervention classes in contrast to classes of the control group. Hence, this study presents a promising program which evidentially prevents cyberbullying in schools.


Asunto(s)
Acoso Escolar , Servicios de Salud Escolar , Adolescente , Conducta del Adolescente , Acoso Escolar/psicología , Niño , Femenino , Alemania , Promoción de la Salud/organización & administración , Humanos , Masculino , Instituciones Académicas , Violencia/prevención & control
3.
J Bodyw Mov Ther ; 29: 223-231, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-35248274

RESUMEN

BACKGROUND: Long-term Proton Pump Inhibitor use is associated with low response rates and the risk of adverse events. OBJECTIVE: The objective of this study was to assess the effectiveness of Osteopathic Treatment in patients with Gastroesophageal Reflux Disease (GERD). METHODS: This study was a randomized controlled trial with a series of osteopathic interventions and an untreated control group. Patients in the osteopathic group (OG) received 4 osteopathic treatments within a time of eight weeks. The control group (CG) did not receive any osteopathic treatment. Primary outcome parameters were gastrointestinal symptoms, assessed by means of the Reflux Disease Questionnaire (RDQ). Secondary outcome parameters were Quality of life with regards to GERD symptoms, assessed by means of the Quality of Life in Reflux and Dyspepsia (QUOLRAD) questionnaire, medication use and osteopathic dysfunctions. RESULTS: Seventy patients were randomized. RDQ mean scores decreased statistically significantly in the OG but did not change in the CG; however, these data cannot be interpreted due to a large number of incorrectly completed questionnaires. The between group difference of the changes for the QOLRAD score was statistically significant 0.69 [95%CI = 0.35 to 1.0]. At week 20, changes in the QOLRAD of the OG were sustainable. Medication use decreased substantially in the OG whilst it remained the same in the CG. CONCLUSION: A series of osteopathic treatments might potentially be beneficial for patients suffering from GERD. Future studies should include longer follow-up times and establish the clinical significance of results by introducing a global rating of change measurement.


Asunto(s)
Reflujo Gastroesofágico , Calidad de Vida , Reflujo Gastroesofágico/terapia , Humanos , Encuestas y Cuestionarios , Resultado del Tratamiento
4.
Complement Med Res ; 25(2): 122-128, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-28892807

RESUMEN

OBJECTIVE: To assess the effectiveness of osteopathic intervention (OI) and general osteopathic treatment (GOT) in individuals with fibromyalgia syndrome (FMS). METHODS: The trial was designed as a randomized controlled trial with 2 osteopathic interventions and 1 untreated control group. The patients in the two osteopathic groups received 10 osteopathic treatments (OI or GOT) within a time period of 12 weeks. The control group did not receive any osteopathic treatment. The primary outcome was the average pain intensity (API) assessed by visual analog scale (VAS). Secondary outcomes were the pressure-pain threshold rated by means of a tender point score, and disease severity, assessed by the Fibromyalgia Impact Questionnaire (FIQ). RESULTS: 50 patients were randomized. The primary outcome parameter API decreased from 7.2 to 4.7 in the OI group, from 6.3 to 4.3 in the GOT group, and increased slightly in the control group from 6.2 to 6.6. There were significant differences for the change in API between the OI group and the control group (VAS: 2.9, 95% confidence interval (CI) = 1.12-4.52), and between the GOT group and the control group (VAS: 2.4, 95% CI = 0.65-4.11), but no significant differences between the OI group and the GOT group. There were no significant differences for the secondary outcome parameters between the groups. CONCLUSION: A series of osteopathic treatments might be beneficial for patients suffering from FMS.


Asunto(s)
Fibromialgia/terapia , Osteopatía , Adulto , Anciano , Femenino , Humanos , Masculino , Osteopatía/métodos , Persona de Mediana Edad , Dolor , Umbral del Dolor , Presión/efectos adversos , Índice de Severidad de la Enfermedad
5.
PLoS One ; 10(6): e0129904, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26103514

RESUMEN

OBJECTIVE: 1) to assess the preparedness to practice and satisfaction in learning environment amongst new graduates from European osteopathic institutions; 2) to compare the results of preparedness to practice and satisfaction in learning environment between and within countries where osteopathy is regulated and where regulation is still to be achieved; 3) to identify possible correlations between learning environment and preparedness to practice. METHOD: Osteopathic education providers of full-time education located in Europe were enrolled, and their final year students were contacted to complete a survey. Measures used were: Dundee Ready Educational Environment Measure (DREEM), the Association of American Medical Colleges (AAMC) and a demographic questionnaire. Scores were compared across institutions using one-way ANOVA and generalised linear model. RESULTS: Nine European osteopathic education institutions participated in the study (4 located in Italy, 2 in the UK, 1 in France, 1 in Belgium and 1 in the Netherlands) and 243 (77%) of their final-year students completed the survey. The DREEM total score mean was 121.4 (SEM: 1.66) whilst the AAMC was 17.58 (SEM:0.35). A generalised linear model found a significant association between not-regulated countries and total score as well as subscales DREEM scores (p<0.001). Learning environment and preparedness to practice were significantly positively correlated (r=0.76; p<0.01). DISCUSSION: A perceived higher level of preparedness and satisfaction was found amongst students from osteopathic institutions located in countries without regulation compared to those located in countries where osteopathy is regulated; however, all institutions obtained a 'more positive than negative' result. Moreover, in general, cohorts with fewer than 20 students scored significantly higher compared to larger student cohorts. Finally, an overall positive correlation between students' preparedness and satisfaction were found across all institutions recruited.


Asunto(s)
Aprendizaje , Medicina Osteopática/educación , Europa (Continente) , Humanos
6.
Front Biosci (Landmark Ed) ; 18(3): 1129-40, 2013 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-23747872

RESUMEN

Surfactant Protein A (SP-A) and D (SP-D) are calcium-dependent collagen-containing lectins, also called collectins, which play a significant role in surfactant homeostasis and pulmonary immunity. The role of SP-A and SP-D in immune defence is well- established. They are known to bind to a range of microbial pathogens that invade the lungs and target them for phagocytic clearance by resident alveolar macrophages. They are also involved in the clearance of apoptotic and necrotic cells and subsequent resolution of pulmonary inflammation. To date, the molecular mechanisms by which SP-A and SP-D interact with various immune cells are poorly understood. In spite of overall structural similarity, SP-A and SP-D show a number of functional differences in their interaction with surface molecules of microorganisms and host cells. The aim of this review is to provide an overview of the current knowledge of ligands and receptors that are known to interact with SP-A and SP-D.


Asunto(s)
Proteína A Asociada a Surfactante Pulmonar/metabolismo , Proteína D Asociada a Surfactante Pulmonar/metabolismo , Receptores de Superficie Celular/metabolismo , Humanos , Ligandos
7.
Expert Rev Anti Infect Ther ; 11(6): 597-604, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23750731

RESUMEN

This review describes current knowledge on the severity and long-term sequelae of meningococcal disease (MD) specifically. The literature databases Medline and Embase were used by combining search terms for MD and Neisseria meningitidis with terms for severity, mortality and sequelae. Case fatality for sufferers of MD remains high, typically 5-10%, despite the best medical care. Long-term sequelae in survivors may include physical, neurological, cognitive, behavioral and psychological consequences, such as hearing loss, amputations, skin scarring and neurodevelopmental deficits. A significantly lower quality of life is seen in survivors of MD compared with unaffected controls, with detrimental effects of childhood MD continuing into adulthood. MD carries a substantial risk of long-term sequelae and mortality. This should be recognized by physicians treating patients with this disease and lends support for the implementation of preventative measures such as vaccination.


Asunto(s)
Infecciones Meningocócicas/fisiopatología , Neisseria meningitidis/patogenicidad , Adulto , Amputación Quirúrgica , Niño , Cicatriz/fisiopatología , Pérdida Auditiva/fisiopatología , Humanos , Infecciones Meningocócicas/microbiología , Infecciones Meningocócicas/mortalidad , Neisseria meningitidis/fisiología , Calidad de Vida , Índice de Severidad de la Enfermedad , Análisis de Supervivencia , Sobrevivientes , Factores de Tiempo
8.
Appl Health Econ Health Policy ; 11(1): 27-43, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23329379

RESUMEN

INTRODUCTION: Non-small cell lung cancer (NSCLC) is associated with high morbidity and mortality. Surgery is generally accepted as the first-line treatment in patients with advanced/metastatic NSCLC, followed by radiotherapy and chemotherapy as second-line treatments. Docetaxel or erlotinib are generally recommended as the first-line chemotherapy option. The objective of this review was to identify previously published economic evaluations in NSCLC for second- and later-line treatments in order to (i) determine common modelling approaches and (ii) establish the relative cost effectiveness of these treatments. An overview of model critique was also produced to identify common criticisms from health technology assessment (HTA) bodies on the models submitted. METHODS: MEDLINE, Embase, EconLit, MEDLINE in Process(®) and NHS Economic Evaluation Database (NHSEED) were searched (database start-October 2011), along with proceedings from eight major conferences (2007-2011). National Institute for Health and Clinical Excellence (NICE), Scottish Medicines Consortium (SMC), Pharmaceutical Benefits Advisory Committee (PBAC) and Canadian Agency for Drugs and Technologies in Health (CADTH) websites and the International Network of Agencies for Health Technology Assessment (INAHTA) database were also searched for appraisals in second- or later-line NSCLC. All published studies and HTA appraisals that reported economic evaluations of interventions used in current clinical practice as second- or later-line treatment in patients with advanced/metastatic NSCLC were included. Only studies in English were considered for inclusion. Studies which met the eligibility criteria after the screening of full-text articles were extracted by a reviewer and checked by a second party. Where multiple publications were identified describing a single study, the extracted data were compiled into one entry. RESULTS: A total of 29 studies were included which clearly evaluated second-line or later-line regimens. Most studies were either cost-effectiveness or cost-utility evaluations. Three-state transition Markov models were frequently used in cost-effectiveness and cost-utility evaluations. The model inputs were well reported and commonly consisted of data from pivotal trials. Sensitivity analyses were conducted in the majority of studies and covered variables such as cost, effectiveness, hospitalization and treatment duration. Therapies (docetaxel, pemetrexed and erlotinib) are for the most part cost-effective/cost-saving second-line therapies compared with best supportive care (BSC). Six erlotinib HTAs, across NICE, SMC, and PBAC, and four pemetrexed HTAs, one by NICE and three by SMC, were identified. The CADTH website did not provide sufficient detail on the appraisals and was excluded. Certain aspects of the models and model assumptions, e.g. efficacy inputs, were criticized or determined unjustifiable by the NICE, SMC and PBAC appraisal committees. Erlotinib and pemetrexed were considered to be cost effective versus docetaxel by NICE and SMC in the final submissions. PBAC considered erlotinib to be cost effective versus BSC following a price reduction in 2008. CONCLUSION: Three-state Markov models are often used to conduct economic analysis in NSCLC and are regarded as appropriate to HTA agencies. Docetaxel, erlotinib and BSC are suitable comparators that should be considered for use in the model in the UK and Australia. Further, manufacturers should carefully select underlying assumptions used in the model, for both costs and clinical inputs, where the latter is derived from direct head-to-head trial data.


Asunto(s)
Antineoplásicos/economía , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Antineoplásicos/uso terapéutico , Análisis Costo-Beneficio/métodos , Docetaxel , Clorhidrato de Erlotinib , Humanos , Inhibidores de Proteínas Quinasas/economía , Calidad de Vida , Quinazolinas/economía , Taxoides/economía
9.
Complement Ther Med ; 20(6): 456-65, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23131379

RESUMEN

OBJECTIVE: Craniosacral therapy (CST) is an alternative treatment approach, aiming to release restrictions around the spinal cord and brain and subsequently restore body function. A previously conducted systematic review did not obtain valid scientific evidence that CST was beneficial to patients. The aim of this review was to identify and critically evaluate the available literature regarding CST and to determine the clinical benefit of CST in the treatment of patients with a variety of clinical conditions. METHODS: Computerised literature searches were performed in Embase/Medline, Medline(®) In-Process, The Cochrane library, CINAHL, and AMED from database start to April 2011. Studies were identified according to pre-defined eligibility criteria. This included studies describing observational or randomised controlled trials (RCTs) in which CST as the only treatment method was used, and studies published in the English language. The methodological quality of the trials was assessed using the Downs and Black checklist. RESULTS: Only seven studies met the inclusion criteria, of which three studies were RCTs and four were of observational study design. Positive clinical outcomes were reported for pain reduction and improvement in general well-being of patients. Methodological Downs and Black quality scores ranged from 2 to 22 points out of a theoretical maximum of 27 points, with RCTs showing the highest overall scores. CONCLUSION: This review revealed the paucity of CST research in patients with different clinical pathologies. CST assessment is feasible in RCTs and has the potential of providing valuable outcomes to further support clinical decision making. However, due to the current moderate methodological quality of the included studies, further research is needed.


Asunto(s)
Masaje , Análisis Costo-Beneficio , Humanos , Dolor , Resultado del Tratamiento
10.
Curr Med Res Opin ; 28(3): 429-37, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22185430

RESUMEN

OBJECTIVE: Transient ischemic attack (TIA) is a serious condition which should be considered on the same spectrum as other conditions involving brain ischemia. Efficient management of these patients is therefore critical. The aim of this research was to gain insights into 'real-world' global trends of the current management approaches for patients with suspected and diagnosed TIA, and highlight the unmet need and areas of improvement to ensure effective management of this patient group. RESEARCH DESIGN AND METHODS: Tele-interviews were conducted with 120 physicians and five operational managers across France, Germany, Italy, Spain, UK, and the US including stakeholders from primary care group practice, those with hospital responsibilities (ER physician and Neurologists), or from home health agencies. Information from the interviewees regarding the management of patients with TIA (including entrance into the clinical pathway, diagnosis, and treatment) were obtained and analyzed qualitatively. RESULTS: The majority of patients with suspected TIA were reported to enter the clinical pathway via the GP or ER, irrespective of country. Once initially seen, the neurologist then plays a central role in the diagnosis, treatment and follow-up of the patients. Although a number of tests are routinely employed, interviewees reported that streamlining and simplification of diagnosis, faster initiation of treatment, improved efficacy and fewer side-effects with treatment were needed for patients with suspected TIA. The study is designed to provide a directional indication of the current situation rather than strong, quantitative conclusions, given limitations of the small sample size and subjective nature of the data. CONCLUSIONS: The importance of correct management of patients with TIA is becoming increasingly recognized by physicians. Improved education for patients regarding symptom recognition and severity is required along with a standardized diagnostic process. These would enable correct and fast diagnosis and initiation of treatment thereby reducing the risk of further events.


Asunto(s)
Ataque Isquémico Transitorio/diagnóstico , Ataque Isquémico Transitorio/terapia , Estudios de Seguimiento , Francia , Humanos , Entrevistas como Asunto , Italia , Médicos , Derivación y Consulta , Factores de Riesgo , España , Estados Unidos
11.
J Am Osteopath Assoc ; 111(12): 685-93, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22182954

RESUMEN

CONTEXT: Cranial osteopathic manipulative medicine (OMM) involves the manipulation of the primary respiratory mechanism to improve structure and function in children and adults. OBJECTIVE: To identify and critically evaluate the literature regarding the clinical efficacy of cranial OMM. DATA SOURCES: The clinical keywords "cranial manipulation" OR "osteopathy in the cranial field" OR "cranial osteopathy" OR "craniosacral technique" were searched in the following electronic databases: EMBASE, MEDLINE In-Process & Other Non-Indexed Citations, The Cochrane Central Register of Controlled Trials, CINAHL (Cumulative Index to Nursing and Allied Health Literature), and AMED (Alternative Medicine). Searches were conducted in April 2011 with no date restriction for when the studies were completed. STUDY SELECTION: Randomized controlled trials and observational studies that measured the effectiveness of cranial OMM on humans were included in the study. Exclusion criteria included non-English language articles, studies not relevant to cranial OMM, animal studies, and studies in which there was no clear indication of the use of cranial OMM. Studies that described the use of cranial OMM with other treatment modalities and that did not perform subgroup analysis were also excluded. The present study did not have criteria regarding type of disease. DATA EXTRACTION: Outcome measures on pain, sleep, quality of life, motor function, and autonomic nervous system function were extracted. The methodological quality of the trials was assessed using the Downs and Black checklist. DATA SYNTHESIS: Of the 8 studies that met the inclusion criteria, 7 were randomized controlled trials and 1 was an observational study. A range of cranial OMM techniques used for the management of a variety of conditions were identified in the included studies. Positive clinical outcomes were reported for pain reduction, change in autonomic nervous system function, and improvement of sleeping patterns. Methodological Downs and Black quality scores ranged from 14 to 23 points out of a maximum of 27 points (overall median score, 16). CONCLUSION: The currently available evidence on the clinical efficacy of cranial OMM is heterogeneous and insufficient to draw definitive conclusions. Because of the moderate methodological quality of the studies and scarcity of available data, further research into this area is needed.


Asunto(s)
Osteopatía/métodos , Medicina Osteopática/métodos , Cráneo , Sistema Nervioso Autónomo , Indicadores de Salud , Humanos , Osteopatía/estadística & datos numéricos , Medicina Osteopática/estadística & datos numéricos , Dolor , Manejo del Dolor/métodos , Calidad de Vida/psicología , Trastornos del Sueño-Vigilia/terapia , Resultado del Tratamiento , Estados Unidos
12.
Protein Cell ; 1(2): 188-97, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21203987

RESUMEN

The role of surfactant protein A (SP-A) in the recognition and clearance of apoptotic cells is well established, but to date, it is still not clear which surface molecules of apoptotic cells are involved in the process. Here we present evidence that phosphatidylserine (PS) is a relevant binding molecule for human SP-A. The binding is Ca(2+)-dependent and is not inhibited by mannose, suggesting that the sugar-binding site of the carbohydrate recognition domain (CRD) of SP-A is not involved. Flow cytometry studies on apoptotic Jurkat cells revealed apparent inhibition of annexin V binding by increasing concentrations of SP-A in late apoptotic but not early apoptotic cells, and this was consistent for Jurkat cells and neutrophils. Supporting these data, confocal microscopy results show a co-localisation of annexin V and SP-A in late apoptotic but not early apoptotic cells. However, we cannot conclude that this inhibition is exclusively due to the binding of SP-A to PS on the cell surface, as annexin V is not wholly specific for PS and SP-A also interacts with other phospholipids that might become exposed on the apoptotic cell surface.


Asunto(s)
Apoptosis , Fosfatidilserinas/metabolismo , Proteína A Asociada a Surfactante Pulmonar/metabolismo , Anexina A5/metabolismo , Carboxiliasas/metabolismo , Citometría de Flujo , Humanos , Células Jurkat , Microscopía Confocal , Neutrófilos/fisiología
13.
Protein Cell ; 1(6): 563-72, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21204009

RESUMEN

Surfactant proteins A (SP-A) and D (SP-D), both members of the collectin family, play a well established role in apoptotic cell recognition and clearance. Recent in vitro data show that SP-A and SP-D interact with apoptotic neutrophils in a distinct manner. SP-A and SP-D bind in a Ca(2+)-dependent manner to viable and early apoptotic neutrophils whereas the much greater interaction with late apoptotic neutrophils is Ca(2+)-independent. Cell surface molecules on the apoptotic target cells responsible for these interactions had not been identified and this study was done to find candidate target molecules. Myeloperoxidase (MPO), a specific intracellular defense molecule of neutrophils that becomes exposed on the outside of the cell upon apoptosis, was identified by affinity purification, mass-spectrometry and western blotting as a novel binding molecule for SP-A and SP-D. To confirm its role in recognition, it was shown that purified immobilised MPO binds SP-A and SP-D, and that MPO is surface-exposed on late apoptotic neutrophils. SP-A and SP-D inhibit binding of an anti-MPO monoclonal Ab to late apoptotic cells. Fluorescence microscopy confirmed that anti-MPO mAb and SP-A/SP-D colocalise on late apoptotic neutrophils. Desmoplakin was identified as a further potential ligand for SP-A, and neutrophil defensin as a target for both proteins.


Asunto(s)
Apoptosis , Neutrófilos/metabolismo , Peroxidasa/metabolismo , Proteína A Asociada a Surfactante Pulmonar/metabolismo , Proteína D Asociada a Surfactante Pulmonar/metabolismo , Unión Competitiva , Técnica del Anticuerpo Fluorescente Indirecta , Humanos , Neutrófilos/química , Neutrófilos/citología , Peroxidasa/aislamiento & purificación , Unión Proteica , Proteína A Asociada a Surfactante Pulmonar/aislamiento & purificación , Proteína D Asociada a Surfactante Pulmonar/aislamiento & purificación
14.
Immunobiology ; 215(7): 551-8, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19880212

RESUMEN

The role of the lung surfactant proteins SP-A and SP-D in immune defence is well established. They bind to foreign organisms that invade the lungs and target them for phagocytic clearance by resident alveolar macrophages. SP-A and SP-D also bind to various apoptotic cells and facilitate their phagocytic uptake. To date, the molecular mechanisms by which the lung surfactant proteins interact with apoptotic cells and phagocytes are poorly understood. The aims of this study were to investigate further the interactions between SP-A and SP-D and apoptotic cells using human neutrophils and Jurkat cells as model systems. Specifically the binding behaviour of SP-A and SP-D with viable, early apoptotic and late apoptotic cells was investigated and compared. SP-A and SP-D show very distinct binding to the various cell types. SP-A bound to viable and early apoptotic cells in a predominantly Ca(2+)-dependent manner but the interaction with late apoptotic cells was Ca(2+)-independent, suggesting involvement of other than the lectin- or Ca(2+)-binding sites. This was consistent for neutrophils and Jurkat cells. SP-D in contrast, did not interact with viable and early apoptotic Jurkat cells but strongly and in a Ca(2+)-independent manner with late apoptotic Jurkat cells. SP-D-binding to viable and early apoptotic neutrophils was inhibited by maltose and ethylene-diamin-tetra-acetate (EDTA), suggesting lectin-binding site involvement whereas the binding to late apoptotic neutrophils was predominantly Ca(2+)-independent. These results represent a detailed study of the binding behaviour of SP-A and SP-D with different cell types and stages of viability. The mechanisms of these interactions appear to involve preferential recognition of different ligands on the apoptotic cell surface, which may include nucleic acid, phospholipid, protein and glycan structures.


Asunto(s)
Neutrófilos/metabolismo , Proteína A Asociada a Surfactante Pulmonar/metabolismo , Proteína D Asociada a Surfactante Pulmonar/metabolismo , Apoptosis/efectos de los fármacos , Apoptosis/inmunología , Señalización del Calcio/inmunología , Separación Celular , Ácido Edético/farmacología , Citometría de Flujo , Humanos , Células Jurkat , Maltosa/farmacología , Neutrófilos/efectos de los fármacos , Neutrófilos/inmunología , Neutrófilos/patología , Unión Proteica/efectos de los fármacos , Unión Proteica/inmunología , Proteína A Asociada a Surfactante Pulmonar/inmunología , Proteína A Asociada a Surfactante Pulmonar/aislamiento & purificación , Proteína D Asociada a Surfactante Pulmonar/inmunología , Proteína D Asociada a Surfactante Pulmonar/aislamiento & purificación , Estaurosporina/metabolismo
15.
Protein Cell ; 1(9): 859-70, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21203928

RESUMEN

Dendritic-cell-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN; CD209) has an important role in mediating adherence of Mycobacteria species, including M. tuberculosis and M. bovis BCG to human dendritic cells and macrophages, in which these bacteria can survive intracellularly. DC-SIGN is a C-type lectin, and interactions with mycobacterial cells are believed to occur via mannosylated structures on the mycobacterial surface. Recent studies suggest more varied modes of binding to multiple mycobacterial ligands. Here we identify, by affinity chromatography and mass-spectrometry, four novel ligands of M. bovis BCG that bind to DC-SIGN. The novel ligands are chaperone protein DnaK, 60 kDa chaperonin-1 (Cpn60.1), glyceraldehyde-3 phosphate dehydrogenase (GAPDH) and lipoprotein lprG. Other published work strongly suggests that these are on the cell surface. Of these ligands, lprG appears to bind DC-SIGN via typical proteinglycan interactions, but DnaK and Cpn60.1 binding do not show evidence of carbohydrate-dependent interactions. LprG was also identified as a ligand for DC-SIGNR (L-SIGN; CD299) and the M. tuberculosis orthologue of lprG has been found previously to interact with human toll-like receptor 2. Collectively, these findings offer new targets for combating mycobacterial adhesion and within-host survival, and reinforce the role of DCSIGN as an important host ligand in mycobacterial infection.


Asunto(s)
Moléculas de Adhesión Celular/metabolismo , Lectinas Tipo C/metabolismo , Mycobacterium bovis/metabolismo , Receptores de Superficie Celular/metabolismo , Secuencia de Aminoácidos , Adhesión Bacteriana/fisiología , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Moléculas de Adhesión Celular/genética , Cromatografía de Afinidad , Células Dendríticas/metabolismo , Células Dendríticas/microbiología , Interacciones Huésped-Patógeno/genética , Interacciones Huésped-Patógeno/fisiología , Humanos , Técnicas In Vitro , Lectinas Tipo C/genética , Ligandos , Macrófagos/metabolismo , Macrófagos/microbiología , Espectrometría de Masas , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Modelos Biológicos , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Datos de Secuencia Molecular , Mycobacterium bovis/genética , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/metabolismo , Mycobacterium tuberculosis/patogenicidad , Proteína A Asociada a Surfactante Pulmonar/metabolismo , Receptores de Superficie Celular/genética
16.
Vaccine ; 26(51): 6655-63, 2008 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-18835574

RESUMEN

Sera from healthy infants (under 1 year old), toddlers (3-4 years) and adults (18-65 years) were assayed for their ability to bind to inner core (ic) lipopolysaccharide (LPS) epitopes of Neisseria meningitidis. Antibodies (Abs) reacting to inner core structures, including different substitutions of the first heptose (HepI) and second heptose (HepII) residues of the LPS backbone, truncated and fully extended LPS glycoforms, were detected and for each structure, these inner core antibodies showed an age-related pattern of acquisition. A novel column-based methodology was used to affinity purify IgG antibodies in which purified inner core LPS (derived from a mutant MC58) was covalently linked to Sepharose 4B. Comparison of reactivity before and after affinity purification of the pooled sera showed that the purified Abs bound to the surface of N. meningitidis organisms displaying truncated and extended LPS with a homologous inner core region, promoted the deposition of C3b, were opsonophagocytic in vitro and decreased bacteraemia when used to passively protect infants rats. In addition, the purified Abs were bactericidal in vitro against the mutant strain displaying truncated LPS with a homologous inner core region. These results demonstrate that naturally occurring serum human antibodies to N. meningitidis LPS can access inner core epitopes of encapsulated organisms with a fully extended LPS.


Asunto(s)
Anticuerpos Antibacterianos/inmunología , Epítopos/inmunología , Lipopolisacáridos/inmunología , Neisseria meningitidis/inmunología , Adolescente , Adulto , Factores de Edad , Anciano , Animales , Anticuerpos Antibacterianos/sangre , Anticuerpos Antibacterianos/aislamiento & purificación , Preescolar , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Inmunoglobulina G/aislamiento & purificación , Lactante , Infecciones Meningocócicas/inmunología , Infecciones Meningocócicas/prevención & control , Persona de Mediana Edad , Ratas , Prueba Bactericida de Suero , Adulto Joven
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