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1.
J Intern Med ; 289(3): 385-394, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32902028

RESUMEN

BACKGROUND: Coronavirus disease 2019 (COVID-19) is a global health emergency. Despite the widely hypothesized role of a cytokine storm in disease severity, no study thus far has explored the association between immunosuppression and disease severity in patients hospitalized with COVID-19. OBJECTIVE: This study aimed to examine the association between the use of immunosuppressant medication and outcomes of patients hospitalized with COVID-19. METHODS: Nine hundred and eighty-one consecutive patients hospitalized between 12 March 2020 and 15 April 2020, who tested positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), were enrolled in this cohort study and subdivided by immunosuppression status. The patients were followed up for a minimum of 28 days (median 37 days) for the primary end-point of mortality. Secondary end-points included the composite of intubation or death, and the composite of mortality, intubation or continuous positive airway pressure (CPAP) requirement. RESULTS: During the follow-up period, 354 (36.1%) of study patients died. The immunosuppressed cohort (n = 31) had significantly higher mortality rates (aHR: 2.067, 95% CI: 1.20-3.57, P = 0.009). There was no association between immunosuppression and the composite end-point of mortality or intubation (aHR: 1.49 95% CI: 0.88-2.51, P = 0.14) and of the composite end-point of mortality, intubation or CPAP (aHR: 1.36 95% CI: 0.81-2.30 P = 0.245). CONCLUSION: In this cohort study of 981 confirmed COVID-19 patients consecutively hospitalized at a large North West London hospital, immunosuppressant use was associated with significantly higher mortality rates. These results support the current UK government's early isolation ('shielding') policy for these individuals and should be used to guide future research.


Asunto(s)
COVID-19/epidemiología , COVID-19/inmunología , Hospitalización , Huésped Inmunocomprometido , Neumonía Viral/epidemiología , Neumonía Viral/inmunología , Anciano , Anciano de 80 o más Años , COVID-19/mortalidad , Presión de las Vías Aéreas Positiva Contínua , Femenino , Mortalidad Hospitalaria , Humanos , Inmunosupresores/administración & dosificación , Londres/epidemiología , Masculino , Persona de Mediana Edad , Pandemias , Neumonía Viral/mortalidad , Neumonía Viral/virología , SARS-CoV-2
2.
Epidemiol Infect ; 148: e251, 2020 10 13.
Artículo en Inglés | MEDLINE | ID: mdl-33046155

RESUMEN

COVID-19 has caused a major global pandemic and necessitated unprecedented public health restrictions in almost every country. Understanding risk factors for severe disease in hospitalised patients is critical as the pandemic progresses. This observational cohort study aimed to characterise the independent associations between the clinical outcomes of hospitalised patients and their demographics, comorbidities, blood tests and bedside observations. All patients admitted to Northwick Park Hospital, London, UK between 12 March and 15 April 2020 with COVID-19 were retrospectively identified. The primary outcome was death. Associations were explored using Cox proportional hazards modelling. The study included 981 patients. The mortality rate was 36.0%. Age (adjusted hazard ratio (aHR) 1.53), respiratory disease (aHR 1.37), immunosuppression (aHR 2.23), respiratory rate (aHR 1.28), hypoxia (aHR 1.36), Glasgow Coma Scale <15 (aHR 1.92), urea (aHR 2.67), alkaline phosphatase (aHR 2.53), C-reactive protein (aHR 1.15), lactate (aHR 2.67), platelet count (aHR 0.77) and infiltrates on chest radiograph (aHR 1.89) were all associated with mortality. These important data will aid clinical risk stratification and provide direction for further research.


Asunto(s)
Betacoronavirus , Infecciones por Coronavirus/epidemiología , Neumonía Viral/epidemiología , Anciano , Anciano de 80 o más Años , COVID-19 , Infecciones por Coronavirus/complicaciones , Infecciones por Coronavirus/mortalidad , Femenino , Hospitalización , Humanos , Londres/epidemiología , Masculino , Persona de Mediana Edad , Pandemias , Neumonía Viral/complicaciones , Neumonía Viral/mortalidad , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Factores de Riesgo , SARS-CoV-2
3.
Clin Exp Immunol ; 179(3): 378-91, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25113810

RESUMEN

Expression of the adhesion molecule, CD146/MCAM/MelCAM, on T cells has been associated with recent activation, memory subsets and T helper type 17 (Th17) effector function, and is elevated in inflammatory arthritis. Th17 cells have been implicated in the pathogenesis of rheumatoid arthritis (RA) and spondyloarthritides (SpA). Here, we compared the expression of CD146 on CD4(+) T cells between healthy donors (HD) and patients with RA and SpA [ankylosing spondylitis (AS) or psoriatic arthritis (PsA)] and examined correlations with surface markers and cytokine secretion. Peripheral blood mononuclear cells (PBMC) were obtained from patients and controls, and synovial fluid mononuclear cells (SFMC) from patients. Cytokine production [elicited by phorbol myristate acetate (PMA)/ionomycin] and surface phenotypes were evaluated by flow cytometry. CD146(+) CD4(+) and interleukin (IL)-17(+) CD4(+) T cell frequencies were increased in PBMC of PsA patients, compared with HD, and in SFMC compared with PBMC. CD146(+) CD4(+) T cells were enriched for secretion of IL-17 [alone or with IL-22 or interferon (IFN)-γ] and for some putative Th17-associated surface markers (CD161 and CCR6), but not others (CD26 and IL-23 receptor). CD4(+) T cells producing IL-22 or IFN-γ without IL-17 were also present in the CD146(+) subset, although their enrichment was less marked. Moreover, a majority of cells secreting these cytokines lacked CD146. Thus, CD146 is not a sensitive or specific marker of Th17 cells, but rather correlates with heterogeneous cytokine secretion by subsets of CD4(+) helper T cells.


Asunto(s)
Artritis Psoriásica/inmunología , Artritis Reumatoide/inmunología , Antígeno CD146/metabolismo , Interleucina-17/metabolismo , Espondilitis Anquilosante/inmunología , Subgrupos de Linfocitos T/inmunología , Células Th17/inmunología , Adulto , Anciano , Biomarcadores/metabolismo , Antígeno CD146/genética , Células Cultivadas , Femenino , Regulación de la Expresión Génica , Humanos , Memoria Inmunológica , Interferón gamma/metabolismo , Interleucinas/metabolismo , Activación de Linfocitos , Masculino , Persona de Mediana Edad , Interleucina-22
4.
Br J Cancer ; 111(5): 828-36, 2014 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-24983367

RESUMEN

BACKGROUND: Predictive biomarker development is a key challenge for novel cancer therapeutics. We explored the feasibility of next-generation sequencing (NGS) to validate exploratory genomic biomarkers that impact phase I trial selection. METHODS: We prospectively enrolled 158 patients with advanced solid tumours referred for phase I clinical trials at the Royal Marsden Hospital (October 2012 to March 2013). After fresh and/or archived tumour tissue were obtained, 93 patients remained candidates for phase I trials. Results from tumour sequencing on the Illumina MiSeq were cross-validated in 27 out of 93 patients on the Ion Torrent Personal Genome Machine (IT-PGM) blinded to results. MiSeq validation with Sequenom MassARRAY OncoCarta 1.0 (Sequenom Inc., San Diego, CA, USA) was performed in a separate cohort. RESULTS: We found 97% concordance of mutation calls by MiSeq and IT-PGM at a variant allele frequency ⩾13% and ⩾500 × depth coverage, and 91% concordance between MiSeq and Sequenom. Common 'actionable' mutations involved deoxyribonucleic acid (DNA) repair (51%), RAS-RAF-MEK (35%), Wnt (26%), and PI3K-AKT-mTOR (24%) signalling. Out of 53, 29 (55%) patients participating in phase I trials were recommended based on identified actionable mutations. CONCLUSIONS: Targeted high-coverage NGS panels are a highly feasible single-centre technology well-suited to cross-platform validation, enrichment of trials with molecularly defined populations and hypothesis testing early in drug development.


Asunto(s)
Biomarcadores de Tumor/genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Neoplasias/genética , Adulto , Anciano , Femenino , Frecuencia de los Genes/genética , Humanos , Masculino , Persona de Mediana Edad , Mutación/genética , Estudios Prospectivos , Reproducibilidad de los Resultados , Análisis de Secuencia de ADN/métodos , Adulto Joven
5.
Anaesthesia ; 69 Suppl 1: 81-98, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24303864

RESUMEN

Increasing numbers of elderly patients are undergoing an increasing variety of surgical procedures. There is an age-related decline in physiological reserve, which may be compounded by illness, cognitive decline, frailty and polypharmacy. Compared with younger surgical patients, the elderly are at relatively higher risk of mortality and morbidity after elective and (especially) emergency surgery. Multidisciplinary care improves outcomes for elderly surgical patients. Protocol-driven integrated pathways guide care effectively, but must be individualised to suit each patient. The AAGBI strongly supports an expanded role for senior geriatricians in coordinating peri-operative care for the elderly, with input from senior anaesthetists (consultants/associate specialists) and surgeons. The aims of peri-operative care are to treat elderly patients in a timely, dignified manner, and to optimise rehabilitation by avoiding postoperative complications. Effective peri-operative care improves the likelihood of very elderly surgical patients returning to their same pre-morbid place of residence, and maintains the continuity of their community care when in hospital. Postoperative delirium is common, but underdiagnosed, in elderly surgical patients, and delays rehabilitation. Multimodal intervention strategies are recommended for preventing postoperative delirium. Peri-operative pain is common, but underappreciated, in elderly surgical patients, particularly if they are cognitively impaired. Anaesthetists should administer opioid-sparing analgesia where possible, and follow published guidance on the management of pain in older people. Elderly patients should be assumed to have the mental capacity to make decisions about their treatment. Good communication is essential to this process. If they clearly lack that capacity, proxy information should be sought to determine what treatment, if any, is in the patient's best interests. Anaesthetists must not ration surgical or critical care on the basis of age, but must be involved in discussions about the utility of surgery and/or resuscitation. The evidence base informing peri-operative care for the elderly remains poor. Anaesthetists are strongly encouraged to become involved in national audit projects and outcomes research specifically involving elderly surgical patients.


Asunto(s)
Anestesia/métodos , Anestesiología/métodos , Servicios Médicos de Urgencia/métodos , Servicios de Salud para Ancianos , Atención Perioperativa/métodos , Anciano , Anciano de 80 o más Años , Humanos , Irlanda , Reino Unido
6.
Science ; 277(5327): 828-31, 1997 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-9242614

RESUMEN

Female chimpanzees often forage alone and do not display obvious linear dominance hierarchies; consequently, it has been suggested that dominance is not of great importance to them. However, with the use of data from a 35-year field study of chimpanzees, high-ranking females were shown to have significantly higher infant survival, faster maturing daughters, and more rapid production of young. Given the foraging behavior of chimpanzees, high rank probably influences reproductive success by helping females establish and maintain access to good foraging areas rather than by sparing them stress from aggression.


Asunto(s)
Pan troglodytes/psicología , Reproducción , Predominio Social , Animales , Conducta Animal , Conducta Alimentaria , Femenino , Longevidad , Masculino , Pan troglodytes/fisiología , Maduración Sexual , Tanzanía
7.
Science ; 265(5176): 1193-201, 1994 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-7915048

RESUMEN

Hypotheses about chimpanzee social behavior, phylogeography, and evolution were evaluated by noninvasive genotyping of free-ranging individuals from 20 African sites. Degrees of relatedness among individuals in one community were inferred from allele-sharing at eight nuclear simple sequence repeat (SSR) loci. Males are related on the order of half-siblings, and homozygosity is significantly increased at several SSR loci compared to Hardy-Weinberg expectations. These data support the kin-selection hypothesis for the evolution of cooperation among males. Sequence variation patterns at two mitochondrial loci indicate historically high long-distance gene flow and clarify the relationships among three allopatric subspecies. The unexpectedly large genetic distance between the western subspecies, Pan troglodytes verus, and the other two subspecies suggests a divergence time of about 1.58 million years. This result, if confirmed at nuclear loci and supported by eco-behavioral data, implies that P. t. verus should be elevated to full species rank.


Asunto(s)
Evolución Biológica , Variación Genética , Pan troglodytes/genética , Conducta Social , África , Alelos , Animales , Secuencia de Bases , ADN/análisis , ADN/genética , Femenino , Cabello/química , Masculino , Datos de Secuencia Molecular , Pan troglodytes/clasificación , Pan troglodytes/psicología , Filogenia , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Secuencias Repetitivas de Ácidos Nucleicos , Tanzanía
8.
Am J Primatol ; 70(8): 766-77, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18506732

RESUMEN

Understanding the rates and causes of mortality in wild chimpanzee populations has important implications for a variety of fields, including wildlife conservation and human evolution. Because chimpanzees are long-lived, accurate mortality data requires very long-term studies. Here, we analyze 47 years of data on the Kasekela community in Gombe National Park. Community size fluctuated between 38 and 60, containing 60 individuals in 2006. From records on 220 chimpanzees and 130 deaths, we found that the most important cause of mortality in the Kasekela community was illness (58% of deaths with known cause), followed by intraspecific aggression (20% of deaths with known cause). Previous studies at other sites also found that illness was the primary cause of mortality and that some epidemic disease could be traced to humans. As at other study sites, most deaths due to illness occurred during epidemics, and the most common category of disease was respiratory. Intraspecific lethal aggression occurred within the community, including the killing of infants by both males and females, and among adult males during the course of dominance-related aggression. Aggression between communities resulted in the deaths of at least five adult males and two adult females in the Kasekela and Kahama communities. The frequency of intercommunity violence appears to vary considerably among sites and over time. Intercommunity lethal aggression involving the Kasekela community was observed most frequently during two periods. Other less common causes of death included injury, loss of mother, maternal disability, and poaching.


Asunto(s)
Enfermedades del Simio Antropoideo/mortalidad , Causas de Muerte , Pan troglodytes , Distribución por Edad , Agresión , Animales , Enfermedades Transmisibles/mortalidad , Enfermedades Transmisibles/veterinaria , Conservación de los Recursos Naturales , Femenino , Masculino , Caracteres Sexuales , Tanzanía
9.
Biochim Biophys Acta ; 1089(2): 257-8, 1991 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-2054386

RESUMEN

Porcine interleukin 2 (IL-2) cDNA was cloned by polymerase chain reaction (PCR), using primers derived from the corresponding bovine sequence. The resulting porcine DNA sequence encodes a 154 residue IL-2 primary translation product. Comparison of the mature, secreted form of porcine IL-2 with those of other species was carried out in an attempt to identify differences that might contribute to the observed differing species specificities.


Asunto(s)
ADN/genética , Interleucina-2/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Sitios de Unión , Bovinos , Clonación Molecular , Humanos , Ratones , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Biosíntesis de Proteínas , Receptores de Interleucina-2/genética , Receptores de Interleucina-2/metabolismo , Ovinos , Especificidad de la Especie , Porcinos
10.
Chem Commun (Camb) ; 51(35): 7501-4, 2015 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-25835242

RESUMEN

The mineral greigite presents similar surface structures to the active sites found in many modern-day enzymes. We show that particles of greigite can reduce CO2 under ambient conditions into chemicals such as methanol, formic, acetic and pyruvic acid. Our results also lend support to the Origin of Life theory on alkaline hydrothermal vents.


Asunto(s)
Dióxido de Carbono/química , Hierro/química , Sulfuros/química , Ácido Acético/química , Catálisis , Técnicas Electroquímicas , Formiatos/química , Metanol/química , Oxidación-Reducción , Presión , Ácido Pirúvico/química , Temperatura , Termodinámica
11.
Br J Pharmacol ; 88(3): 645-51, 1986 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-3017490

RESUMEN

The effects of the opioid receptor agonist RX783006 and of the opioid receptor partial agonist (+)-meptazinol have been examined on electrically induced twitch responses of the guinea-pig isolated ileum and of the mouse isolated vas deferens. Log10 concentration-tissue state curves were determined for (+)-meptazinol and RX783006, alone, in combination and in the presence of naloxone (30 nM). Analysis of these log10 concentration-tissue state curves using the null equations derived and tested in the preceding paper indicates that the opioid agonist action of (+)-meptazinol on mouse vas deferens is quantitatively similar to that on guinea-pig ileum. The results also suggest that (+)-meptazinol acts as a functional antagonist on the guinea-pig ileum as well as on the mouse vas deferens. The potency of (+)-meptazinol relative to RX783006 has been measured by an indirect method which should eliminate any functional antagonistic action of (+)-meptazinol. This method gives a relative potency of (+)-meptazinol in both tissues which is three to six times greater than that measured directly on guinea-pig ileum. This discrepancy may be due to experimental error but it may also indicate that direct measurements on guinea-pig ileum underestimate the agonist potency of this compound on opioid receptors.


Asunto(s)
Azepinas/farmacología , Meptazinol/farmacología , Músculo Liso/efectos de los fármacos , Receptores Opioides/efectos de los fármacos , Animales , Estimulación Eléctrica , Encefalina Ala(2)-MeFe(4)-Gli(5) , Encefalinas/farmacología , Cobayas , Íleon/efectos de los fármacos , Técnicas In Vitro , Masculino , Ratones , Músculo Liso/fisiología , Conducto Deferente/efectos de los fármacos
12.
Br J Pharmacol ; 85(1): 277-83, 1985 May.
Artículo en Inglés | MEDLINE | ID: mdl-2992651

RESUMEN

The effects of the opioid receptor agonist RX783006 and of the opioid receptor partial agonist (+)-meptazinol have been examined on electrically-induced twitch responses of the guinea-pig isolated ileum and of the mouse isolated vas deferens. Log10 concentration-tissue state curves were determined for (+)-meptazinol and for RX783006, alone, in combination and, when appropriate, in the presence of naloxone (30 nM). Analysis of these log10 concentration-tissue state curves using the null equations derived and verified in the previous paper allows quantitation of the characteristics of the interaction of (+)-meptazinol with the opioid receptors in these tissues. The results indicate that the apparent differences in the actions of (+)-meptazinol on isolated electrically-stimulated guinea-pig ileum and mouse vas deferens can be accounted for without the need to postulate differences between mu-opioid receptors in these two tissues.


Asunto(s)
Íleon/metabolismo , Músculo Liso/metabolismo , Receptores Opioides/metabolismo , Conducto Deferente/metabolismo , Animales , Estimulación Eléctrica , Encefalina Ala(2)-MeFe(4)-Gli(5) , Cobayas , Técnicas In Vitro , Masculino , Meptazinol/farmacología , Ratones , Contracción Muscular/efectos de los fármacos , Fragmentos de Péptidos/farmacología , Receptores Opioides mu , Especificidad de la Especie , beta-Lipotropina/farmacología
13.
Br J Pharmacol ; 88(3): 639-44, 1986 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-3742152

RESUMEN

Null equations have been derived which allow quantification of the agonist properties of a compound that is able to modify the state of a tissue simultaneously by interacting with a particular type of receptor and by other means. Parameters can be estimated which separately characterize the agonist properties of the compound and its functional interactant effect. The null equations have been tested in a model system by using a mixture of papaverine (5 microM) and hexyltrimethylammonium bromide (30 microM) to mimic an agonist which also has functional antagonist properties. The values obtained for the various parameters measured directly and indirectly are in good general agreement, confirming the validity of the model.


Asunto(s)
Receptores de Droga/efectos de los fármacos , Animales , Carbacol/farmacología , Técnicas In Vitro , Yeyuno/efectos de los fármacos , Masculino , Contracción Muscular/efectos de los fármacos , Músculo Liso/efectos de los fármacos , Papaverina/farmacología , Ratas
14.
Hum Immunol ; 60(9): 798-805, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10527386

RESUMEN

The aim of this study was to use TCR sequencing as a tool to address the frequency of antigen specific T cells in different T cell compartments from a rheumatoid arthritis patient. We have previously established a clear link between T cell recognition of a specific Mhsp60 epitope and the amino acid sequence in the CDR3 region of the TCRB chain. This information was used to determine the frequency of these characteristic sequences in unmanipulated synovial fluid (SF), peripheral blood (PB) and hyperplastic lymph node of the same patient by amplification and sequencing. TCRBV sequences identical to those seen in antigen-specific clones, and closely related sequences, were readily identified in SF, where they represented approximately 1% of all T cells, but were absent from PB or lymph node. The prevalence of putative Mhsp60 specific T cells within the SFMC is much greater than previously suggested by limiting dilution assays. Thus, amplification and sequencing may prove a superior technique for tracking the frequency of antigen-specific T cells in different tissues and in a longitudinal fashion.


Asunto(s)
Artritis Reumatoide/inmunología , Receptores de Antígenos de Linfocitos T alfa-beta/inmunología , Linfocitos T/inmunología , Secuencia de Aminoácidos , Chaperonina 60/inmunología , Epítopos de Linfocito T/inmunología , Reordenamiento Génico de la Cadena beta de los Receptores de Antígenos de los Linfocitos T , Humanos , Leucocitos Mononucleares/inmunología , Datos de Secuencia Molecular , Receptores de Antígenos de Linfocitos T alfa-beta/genética , Líquido Sinovial/citología
15.
Hum Immunol ; 42(4): 301-6, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7558914

RESUMEN

A panel of T-cell clones was generated that was specific for amino acid residues 4-13 of the mycobacterial 65-kd stress protein. All the clones were found to express a member of the V beta 5 family, as defined by PCR. However, the clones could be differentiated on the basis of different staining characteristics with the mAb 42/1C1. This antibody is known to recognize both V beta 5.2 and V beta 5.3, as was the PCR primer pair used in the analysis. Sequencing of the TCRs revealed that those clones which were not stained by 42/1C1 expressed a previously unidentified member of the V beta 5 family. By comparing the sequences of the V beta 5 family members that are recognized by 42/1C1 with those that are not, we were able to identify a probable epitope for the antibody. It is also clear from our data that the TCRs of T cells recognizing identical MHC-peptide combinations, although very similar, may be differentiated by mAbs, thereby posing potential problems in any proposed disease therapy involving treatment with monoclonals.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Epítopos/inmunología , Receptores de Antígenos de Linfocitos T alfa-beta/inmunología , Secuencia de Aminoácidos , Especificidad de Anticuerpos , Proteínas Bacterianas/inmunología , Chaperonina 60 , Chaperoninas/inmunología , Células Clonales , Colorantes , Citometría de Flujo , Humanos , Inmunoterapia , Datos de Secuencia Molecular , Homología de Secuencia de Aminoácido
16.
Hum Immunol ; 54(1): 40-7, 1997 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-9154456

RESUMEN

Human T-cell clones that recognize a peptide from mycobacterial heat shock protein 60 in the context of HLA-DP were found to be sensitive to changes in the DPA1 chain of the restricting element, optimal responses being seen with the combination HLA-DPA1*0201 and HLA-DPB*0301. HLA-DP dimers containing HLA-DPA1*01 were only able to present antigenic peptides to T-cell clones when peptides were present throughout the period of coculture of T cells with antigen presenting cells. In contrast the optimal HLA-DP dimer could also stimulate T-cell clones maximally when incubated with peptides for 1 h and then thoroughly washed. This suggests that the DPA1 polymorphism influenced the strength of binding of antigenic peptides to the HLA-DP dimer. Modeling studies identified amino acid 31 of DPA1 as the polymorphic residue most likely to account for this effect. This is the first demonstration that the relatively limited polymorphism displayed by DPA1 has functional consequences.


Asunto(s)
Presentación de Antígeno/genética , Antígenos HLA-DP/genética , Péptidos/inmunología , Polimorfismo Genético/inmunología , Secuencia de Aminoácidos , Chaperonina 60/inmunología , Células Clonales , Antígenos HLA-DP/química , Cadenas alfa de HLA-DP , Humanos , Activación de Linfocitos , Modelos Moleculares , Datos de Secuencia Molecular , Linfocitos T/inmunología
18.
J Epidemiol Community Health ; 35(2): 110-3, 1981 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7299334

RESUMEN

Multiple sclerosis has been reported to have a high prevalence in the Orkney and Shetland Islands and in Caithness in comparison with the highlands of Scotland and the Outer Hebrides-the Western Isles. For this reason a survey was undertaken in the Outer Hebrides and 25 probable and 30 probable and possible patients with multiple sclerosis were found. This is an increase from eight and 11 respectively found in 1954. The present prevalence rate of 97.3 per 100 000 for probable and possible multiple sclerosis is not significantly different from that found in a recent study in the Grampian region in north-east Scotland. Repeated studies in small populations generally show increasing prevalence of multiple sclerosis because some patients are missed in the earlier studies, and over a long period of time there may also be some increase in survival time. This increase has been found in the Orkney and Shetland Islands, in north-east Scotland, and also in the Outer Hebrides.


Asunto(s)
Esclerosis Múltiple/epidemiología , Adulto , Femenino , Antígenos HLA/análisis , Hébridas , Humanos , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/inmunología , Escocia , Reino Unido
19.
J Pharm Pharmacol ; 41(4): 242-6, 1989 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2568463

RESUMEN

Mouse isolated vas deferens responded to field stimulation (0.1 Hz) with twitch responses which were abolished by alpha beta-methyleneadenosine 5'-triphosphate (0.5 microM) and were potentiated 2 to 3 fold by meptazinol (5-300 microM). Exogenous adenosine 5'-triphosphate (4-30 microM) also caused a twitch response but was unaffected by meptazinol (30 microM) as was the response to phenylephrine. The effect of meptazinol on the electrically-induced twitch was reproducible, fast in onset, easily reversed by washing and was still seen in the presence of prazosin (1 microM), yohimbine (1 microM), propranolol (0.1 microM), atropine (0.1 microM), physostigmine (1 microM), cocaine (1 microM) or desmethylimipramine (0.3 microM) indicating that the mechanism involved does not depend on adrenoceptors, cholinergic mechanisms or blockade of uptake. Mouse isolated atria responded to stimulation (1, 2 or 5 Hz) of their sympathetic nerves via transmural electrodes with chronotropic responses which were abolished by atenolol (5 and 50 microM) but were unaffected by alpha beta-methyleneadenosine 5'-triphosphate (0.5 microM). Meptazinol (100 microM) failed to potentiate the responses. It is suggested that meptazinol potentiates the effects of the non-adrenergic non-cholinergic transmitter thought to be involved in the response of the mouse vas deferens to electrical stimulation.


Asunto(s)
Azepinas/farmacología , Meptazinol/farmacología , Sistema Nervioso Simpático/fisiología , Adenosina Trifosfato/análogos & derivados , Adenosina Trifosfato/farmacología , Animales , Estimulación Eléctrica , Técnicas In Vitro , Masculino , Ratones , Contracción Muscular/efectos de los fármacos , Músculo Liso/efectos de los fármacos , Músculo Liso/inervación , Músculo Liso/metabolismo , Músculo Liso Vascular/efectos de los fármacos , Norepinefrina/metabolismo , Sistema Nervioso Simpático/efectos de los fármacos , Conducto Deferente/efectos de los fármacos
20.
J Pharm Pharmacol ; 36(8): 560-2, 1984 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-6148406

RESUMEN

Electrically induced twitch responses of mouse vas deferens and guinea-pig ileum were inhibited by morphine, normorphine and the peptide opioid agonist RX783006; naloxone blocked the effects of all three opioid agonists yielding Ke values which were not significantly different and which were within the range (1-4 nM) expected for mu-type receptors. At concentrations between 0.1 and 10 microM (+)-meptazinol inhibited the twitch response of the ileum while (-)-meptazinol produced potentiation. Naloxone (20 nM) completely blocked the effect of (+)-meptazinol and further increased the potentiation produced by (-)-meptazinol. In the mouse vas deferens preparation neither isomer affected the electrically induced twitch response at concentrations below 5 microM and higher concentrations (10-300 microM) produced potentiation. Naloxone (20 nM) did not modify this effect. It is concluded that both isomers are opioid agonists on the mu-receptors in guinea-pig ileum but not in mouse vas deferens and that a cholinergic component, which may contribute to the action of meptazinol in-vivo, is present to a smaller extent in the (+)-isomer.


Asunto(s)
Azepinas/farmacología , Íleon/efectos de los fármacos , Meptazinol/farmacología , Conducto Deferente/efectos de los fármacos , Animales , Estimulación Eléctrica , Cobayas , Técnicas In Vitro , Masculino , Ratones , Ratones Endogámicos , Contracción Muscular/efectos de los fármacos , Músculo Liso/efectos de los fármacos , Naloxona/farmacología , Narcóticos/farmacología , Estereoisomerismo
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