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1.
Res Involv Engagem ; 7(1): 40, 2021 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-34127076

RESUMEN

BACKGROUND: England operates a National Data Opt-Out (NDOO) for the secondary use of confidential health data for research and planning. We hypothesised that public awareness and support for the secondary use of health data and the NDOO would vary by participant demography and healthcare experience. We explored patient/public awareness and perceptions of secondary data use, grouping potential researchers into National Health Service (NHS), academia or commercial. We assessed awareness of the NDOO system amongst patients, carers, healthcare staff and the public. We co-developed recommendations to consider when sharing unconsented health data for research. METHODS: A patient and public engagement program, co-created and including patient and public workshops, questionnaires and discussion groups regarding anonymised health data use. RESULTS: There were 350 participants in total. Central concerns for health data use included unauthorised data re-use, the potential for discrimination and data sharing without patient benefit. 94% of respondents were happy for their data to be used for NHS research, 85% for academic research and 68% by health companies, but less than 50% for non-healthcare companies and opinions varied with demography and participant group. Questionnaires showed that knowledge of the NDOO was low, with 32% of all respondents, 53% of all NHS staff and 29% of all patients aware of the NDOO. Recommendations to guide unconsented secondary health data use included that health data use should benefit patients; data sharing decisions should involve patients/public. That data should remain in close proximity to health services with the principles of data minimisation applied. Further, that there should be transparency in secondary health data use, including publicly available lists of projects, summaries and benefits. Finally, organisations involved in data access decisions should participate in programmes to increase knowledge of the NDOO, to ensure public members were making informed choices about their own data. CONCLUSION: The majority of participants in this study reported that the use of healthcare data for secondary purposes was acceptable when accessed by NHS. Academic and health-focused companies. However, awareness was limited, including of the NDOO. Further development of publicly-agreed recommendations for secondary health data use may improve both awareness and confidence in secondary health data use.


Health data from routine care can be pseudonymised (with a link remaining to the patient but identifying features removed) or anonymised (with identifying features removed and the link to the patient severed) and used for research and health planning; termed "secondary use". The National Health Service (NHS) is a single publicly-funded health service for the United Kingdom (UK). The NHS supports secondary data use with a National Data opt-out system. The potential benefits of data secondary use are clear but concerns have been raised. Although the Data Opt-Out is publicised, it is unclear how much public awareness there is of this scheme. We report a patient and publicly created and delivered series of activities including > 350 people; with young adults, patients, NHS staff and the public; to assess concerns, knowledge and acceptance of data sharing.Perceptions of and support for secondary health data use varied depending on who was asked (by age, gender) and their experience of health services (Staff member, patient, member of the public). Knowledge of schemes to limit secondary data use (such as the UK National Data Op-Out) was low, even among NHS staff. The main concerns of sharing health data included onward data use, the potential for discrimination and exploitation and commercial gain from data use with no benefit to patients. Despite this, most participants agreed with health data sharing with NHS, academic and commercial health-based entities. Agreed, co-created themes to increase the acceptability of health data secondary use included education about 'Opt-out' schemes, health service oversight of data use (as the most trusted partner), public and patient involvement in data sharing decisions and public transparency.

2.
J Exp Med ; 189(9): 1363-72, 1999 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-10224276

RESUMEN

We have recently shown that expression of the enzyme indoleamine 2, 3-dioxygenase (IDO) during murine pregnancy is required to prevent rejection of the allogeneic fetus by maternal T cells. In addition to their role in pregnancy, IDO-expressing cells are widely distributed in primary and secondary lymphoid organs. Here we show that monocytes that have differentiated under the influence of macrophage colony-stimulating factor acquire the ability to suppress T cell proliferation in vitro via rapid and selective degradation of tryptophan by IDO. IDO was induced in macrophages by a synergistic combination of the T cell-derived signals IFN-gamma and CD40-ligand. Inhibition of IDO with the 1-methyl analogue of tryptophan prevented macrophage-mediated suppression. Purified T cells activated under tryptophan-deficient conditions were able to synthesize protein, enter the cell cycle, and progress normally through the initial stages of G1, including upregulation of IL-2 receptor and synthesis of IL-2. However, in the absence of tryptophan, cell cycle progression halted at a mid-G1 arrest point. Restoration of tryptophan to arrested cells was not sufficient to allow further cell cycle progression nor was costimulation via CD28. T cells could exit the arrested state only if a second round of T cell receptor signaling was provided in the presence of tryptophan. These data reveal a novel mechanism by which antigen-presenting cells can regulate T cell activation via tryptophan catabolism. We speculate that expression of IDO by certain antigen presenting cells in vivo allows them to suppress unwanted T cell responses.


Asunto(s)
Macrófagos/metabolismo , Linfocitos T/citología , Triptófano Oxigenasa/metabolismo , Triptófano/análogos & derivados , Ciclo Celular , División Celular , Células Cultivadas , Técnicas de Cocultivo , Medios de Cultivo , ADN/biosíntesis , Fase G1 , Expresión Génica , Humanos , Indolamina-Pirrol 2,3,-Dioxigenasa , Activación de Linfocitos , Factor Estimulante de Colonias de Macrófagos/farmacología , Macrófagos/efectos de los fármacos , Linfocitos T/metabolismo , Triptófano/metabolismo , Triptófano/farmacología , Triptófano Oxigenasa/genética
3.
Science ; 281(5380): 1191-3, 1998 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-9712583

RESUMEN

In 1953 Medawar pointed out that survival of the genetically disparate (allogeneic) mammalian conceptus contradicts the laws of tissue transplantation. Rapid T cell-induced rejection of all allogeneic concepti occurred when pregnant mice were treated with a pharmacologic inhibitor of indoleamine 2,3-dioxygenase (IDO), a tryptophan-catabolizing enzyme expressed by trophoblasts and macrophages. Thus, by catabolizing tryptophan, the mammalian conceptus suppresses T cell activity and defends itself against rejection.


Asunto(s)
Feto/inmunología , Tolerancia Inmunológica , Linfocitos T/inmunología , Trofoblastos/enzimología , Triptófano Oxigenasa/metabolismo , Triptófano/metabolismo , Animales , Inhibidores Enzimáticos/farmacología , Femenino , Genes MHC Clase I , Genes RAG-1 , Antígenos H-2/genética , Humanos , Indolamina-Pirrol 2,3,-Dioxigenasa , Factor Estimulante de Colonias de Macrófagos/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos CBA , Placenta/enzimología , Embarazo , Linfocitos T/metabolismo , Transgenes , Triptófano/análogos & derivados , Triptófano/farmacología , Triptófano Oxigenasa/antagonistas & inhibidores
4.
Clin Pharmacol Ther ; 35(4): 480-6, 1984 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-6705446

RESUMEN

Acetaminophen metabolism and clearance after a single 1 gm oral dose of the drug was investigated in 12 healthy men, six of whom were cigarette smokers, and in six men who were receiving anticonvulsant drugs for epilepsy. The 12 healthy subjects were studied before and after 1 wk of pretreatment with cimetidine (1 gm/day) or sulfinpyrazone (800 mg/day). There was no significant difference in acetaminophen clearance (ClAP) between nonsmokers and smokers; cimetidine pretreatment had no effect on ClAP. Neither cigarette smoking nor cimetidine pretreatment had a significant effect on any of the metabolic pathways of acetaminophen. In contrast, sulfinpyrazone pretreatment increased ClAP by 23% (from 5.70 +/- 0.21 to 7.00 +/- 0.39 ml/min/kg) and ClAP was 46% greater in the epileptic subjects who received anticonvulsant drugs than in the control group (8.32 +/- 0.45 and 5.70 +/- 0.21 ml/ml/kg). In both cases the increase in ClAP was a result of induction of acetaminophen glucuronidation and oxidation; clearance of the glucuronic acid conjugate was 26% and 59% greater and clearance of the glutathione-derived conjugates (reflecting the activity of the oxidative pathway) was 43% and 60% greater in the groups given sulfinpyrazone and anticonvulsants, respectively.


Asunto(s)
Acetaminofén/metabolismo , Cimetidina/farmacología , Fumar , Sulfinpirazona/farmacología , Administración Oral , Adulto , Anticonvulsivantes/farmacología , Biotransformación , Interacciones Farmacológicas , Epilepsia/metabolismo , Humanos , Cinética , Masculino
5.
Int Rev Immunol ; 18(5-6): 515-25, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10672499

RESUMEN

The mechanisms of induction and maintenance of tolerance in self-reactive T cells in the periphery are poorly understood. Current models assume that successful T cell activation only occurs if ligation of the T cell receptor (signal 1) by antigen presenting cells (APCs) is accompanied by a costimulatory signal (signal 2), and that signal 1 in the absence of signal 2 is either ignored or is tolerizing. However, there is also evidence for the existence of macrophages (M phi) capable of suppressing T cell activation both in vitro and in vivo. The possibility of a more actively induced tolerance exists, in which the M phi itself responds to T cell-mediated signals in a tolerogenic fashion. This would help to resolve the paradox that tissue M phi, which act as scavengers of self-antigen, can also act as professional APCs. The ability of tissue macrophages to actively suppress T cells would further underscore the importance of the innate immune system in regulating adaptive immune responses.


Asunto(s)
Comunicación Celular/inmunología , Tolerancia Inmunológica , Macrófagos/inmunología , Linfocitos T/inmunología , Animales , Humanos , Activación de Linfocitos
6.
Ann N Y Acad Sci ; 615: 256-64, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1674844

RESUMEN

Tuberous sclerosis (TSC) is a multisystem autosomal dominant hamartosis whose genetics is complicated by reduced penetrance and widely varying clinical expression. Results of linkage analyses have variously suggested two different locations for a TSC gene. A collaborative dataset has been assembled to clarify the issue of genetic heterogeneity. We have now analyzed the data from a combined sample of 111 families. Using Ott's HOMOG programs, we completed three tests of homogeneity: (1) for chromosome 9q, (2) for chromosome 11q, and (3) for the combined 9q and 11q data. For test 1 the chi-square (1 df) was 21.54 (p less than 0.001), for test 2 the chi-square (1 df) was 0.13 (p greater than 0.35), and for test 3 the chi-square (2 df) was 37.61 (p less than 0.0001). Additionally, we examined the combined data for evidence that a third, as yet unlinked locus exists. Results of this last test were suggestive but not significant. Clearly loci for TSC are present on both chromosomes 9q and 11q. The maximum likelihood estimate of the proportion of chromosome 9q-linked families is 0.38, for chromosome 11q-linked families is 0.47, and for the unlinked type 0.15. Alternative explanations for these latter families include chance sampling of recombinants, nongenetic phenocopies, or misclassification.


Asunto(s)
Esclerosis Tuberosa/genética , Cromosomas Humanos Par 11 , Cromosomas Humanos Par 9 , Genes Dominantes , Ligamiento Genético , Humanos , Funciones de Verosimilitud , Polimorfismo de Longitud del Fragmento de Restricción
7.
J Gerontol A Biol Sci Med Sci ; 56(6): B268-76, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11382789

RESUMEN

DNA methylation modifies gene expression. Methylation patterns are established during ontogeny, but they change with aging, usually with a net decrease in methylation. The significance of this change in T cells is unknown, but it could contribute to autoimmunity, senescence, or both. We examined the effects of a null mutation in DNA methyltransferase 1 (Dnmt1), a gene maintaining DNA methylation patterns, on immune aging. Whereas aged control mice developed hypomethylated DNA, autoimmunity, and signs of immune senescence as predicted, the knockout mice surprisingly increased DNA methylation and developed signs of autoimmunity and senescence more slowly. To identify potential mechanisms, we compared transcripts of DNA methyltransferase and methylcytosine binding protein family members in control and knockout mice. MeCP2, a methylcytosine binding protein involved in gene suppression and chromatin inactivation, was the only transcript differentially expressed between old knockout mice and controls, and thus it is a candidate for a gene product mediating these effects.


Asunto(s)
Envejecimiento/metabolismo , Autoinmunidad/genética , Proteínas Cromosómicas no Histona , ADN (Citosina-5-)-Metiltransferasas/genética , Metilación de ADN , Heterocigoto , Mutación/fisiología , Proteínas Represoras , Animales , ADN/metabolismo , ADN (Citosina-5-)-Metiltransferasa 1 , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Femenino , Proteína 2 de Unión a Metil-CpG , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados/genética , Valores de Referencia , Factores de Transcripción
8.
Plast Reconstr Surg ; 79(2): 272-7, 1987 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-3809275

RESUMEN

A single patient is presented in whom breast reconstruction after mastectomy for breast cancer has been achieved by sequential use of soft-tissue expansion followed by permanent silicone implant placement and thoracic flap advancement to define the inframammary fold. This procedure may play a useful role in patients in whom other, more complex methods of breast reconstruction are not selected or indicated and in particular in patients in whom bilateral silicone implants are utilized.


Asunto(s)
Mama/cirugía , Colgajos Quirúrgicos , Adulto , Femenino , Estudios de Seguimiento , Humanos , Mastectomía , Reoperación
9.
J Exp Anal Behav ; 37(1): 57-63, 1982 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7057130

RESUMEN

Food-deprived pigeons were presented with a row of four response keys situated above a grain hopper aperture. At the start of a trial, three of four keys were randomly selected and illuminated white for six seconds. After a variable blackout period, one of the three previously white keys and the previously dark key were illuminated green, and the remaining white keys were reilluminated as before. A response to the green key that was previously white was reinforced with three-second access to gain, a response to any other key resulted in a three-second blackout and the start of a new trial. Five of six subjects responded to the correct green key more often than chance at an interstimulus interval of 1.5 seconds, and they displayed maximal performance at different intertrial interval values ranging from 15 to 60 seconds. Choice accuracy decreased for all but one subject as the interstimulus interval was increased. For the range of interstimulus interval durations employed, decrements in choice accuracy were qualitatively similar to, but lower than those typically obtained from, delayed-matching-to-sample or delayed-pair comparison procedures.


Asunto(s)
Percepción de Color , Aprendizaje Discriminativo , Memoria , Recuerdo Mental , Animales , Conducta de Elección , Columbidae , Memoria a Corto Plazo
10.
Ir J Med Sci ; 167(1): 22-5, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9540294

RESUMEN

The potential deleterious effects of doctors' long and arduous shifts have received relatively scant attention. This study addressed the effect of a 32 h on-call shift on 16 pre-registration medical house officers in St. James's Hospital, Dublin. We assessed 5 psychological parameters (Tension-Anxiety, Depression-Dejection, Vigour-Activity, Fatigue-Inertia and Confusion-Bewilderment) as well as 5 simple tests of alertness and concentration both pre- and post-call. The doctors were randomly assigned to be tested either pre- or post-call. On average the doctors got 4.5 hours sleep during a 32 h shift. This long shift had an adverse effect on all the psychological parameters (p < 0.05) except Depression-Dejection. The total mood disturbance score, which has been shown to correlate well with general psychological well-being, deteriorated significantly after the 32 h shift, p < 0.005. Two of the simple tests of alertness and concentration (Trail-making test and Stroop Color-Word test) also showed a significant fall-off in performance with sleep deprivation, p < 0.05, although the remaining tests (Delayed Story Recall, Critical Flicker Fusion and Three Minute Grammatical Reasoning Test) were not significantly impaired by the 32 h shift. This study shows that prolonged periods of duty without sleep adversely affect junior doctors, both in their psychological well-being and in their ability to carry out simple tasks.


Asunto(s)
Fatiga , Cuerpo Médico de Hospitales/psicología , Privación de Sueño , Tolerancia al Trabajo Programado , Adulto , Femenino , Humanos , Masculino , Pruebas Psicológicas , Desempeño Psicomotor , Distribución Aleatoria
18.
Acta Radiol ; 48(2): 213-22, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17354144

RESUMEN

PURPOSE: To investigate whether apparent diffusion coefficient (ADC), fractional anisotropy (FA), and eigenvalues in neuropsychiatric systemic lupus erythematosus (NPSLE) patients differ from those of healthy controls. MATERIAL AND METHODS: Eight NPSLE patients (aged 23-55 years, mean 42.9 years) and 20 healthy age-matched controls (aged 22-59 years, mean 44.4 years) underwent conventional brain magnetic resonance (MR) and diffusion tensor imaging (DTI). The ADC, FA, principal eigenvalue (lambda parallel), and the corresponding average perpendicular eigenvalue (lambda perpendicular) (=(lambda2+lambda3)/2) were measured in selected regions of normal appearing gray and white matter brain parenchyma. For statistical evaluation of differences between the two groups, a Student's t-test was used. The P value for statistical significance was set to P=0.0025 after Bonferroni correction for multiple measurements. RESULTS: Significantly increased ADC values were demonstrated in normal-appearing areas in the insular cortex (P<0.001), thalamus (P<0.001), and the parietal and frontal white matter (P<0.001 and P<0.001, respectively) in NPSLE patients. Significantly decreased FA values were demonstrated in normal-appearing thalamus (P<0.001), corpus callosum (P=0.002), and in the parietal and frontal white matter (P<0.001 and P<0.001, respectively) in NPSLE patients compared to healthy controls. The lambda perpendicular was significantly higher in several of these regions in NPSLE patients compared to healthy controls. CONCLUSION: Our study demonstrates alterations in normal-appearing gray and white matter brain parenchyma of patients with NPSLE by means of abnormal ADC, FA, and eigenvalues. These alterations may be based on loss of tissue integrity in part due to demyelination. It is possible that DTI in the future could assist in the diagnosis of NPSLE and possibly help to further elucidate the pathogenesis of NPSLE.


Asunto(s)
Imagen de Difusión por Resonancia Magnética , Vasculitis por Lupus del Sistema Nervioso Central/patología , Enfermedad Aguda , Adulto , Anisotropía , Estudios de Casos y Controles , Medios de Contraste/administración & dosificación , Femenino , Gadolinio DTPA/administración & dosificación , Humanos , Masculino , Persona de Mediana Edad
19.
Neuroradiology ; 47(8): 576-85, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16007461

RESUMEN

MRI and 2D-CSI spectroscopy were performed in eight patients with systemic lupus erythematosus who presented with acute onset of neuropsychiatric lupus (NP-SLE), and in seven normal controls to evaluate for differences in metabolic peaks and metabolic ratios between the two groups. Also, the interval change of the metabolic peaks and their ratios during treatment in the NP-SLE patient group was evaluated. Metabolic peaks for N-acetyl-aspartate (NAA), choline (Cho), creatine (Cr), and lactate/lipids (LL) and their ratios (NAA/Cr, NAA/Cho, Cho/Cr, LL/Cr) were determined at initial presentation and 3 and 6 months later. In the eight lupus patients compared to the seven normal controls, NAA/Cho ratios were lower at presentation (1.05 vs 1.25; p = 0.004) and decreased even further at the three month follow-up (0.92 vs 1.05; p = 0.008). In contrast, both Cho/Cr (1.42 vs 1.26; p = 0.026) and LL/Cr ratios (0.26 vs 0.19; p = 0.002) were higher in the lupus patients at presentation compared to the controls and did not significantly change at three and six months follow-up. The NAA/Cr ratios were lower in the lupus patients compared to the controls at presentation but the difference was not statistically significant. However, the mean NAA/Cr significantly decreased from the initial examination to the three month follow-up (1.42 vs 1.32; p = 0.049) but did not significantly change from the three to the six month follow-up examinations. The NAA/Cr, Cho/Cr, and NAA/Cho ratios varied significantly (p < 0.05, p < 0.05, p < 0.05, respectively) between the 17 different locations measured in the brain in all eight patients and seven controls. Both the NAA/Cr ratios and the Cho/Cr ratios were also significantly lower in the gray matter than in the white matter (p < 0.0001) in both patients and controls, whereas the LL/Cr and NAA/Cho ratios were not significantly different. In conclusion, 2D-CSI MR spectroscopy may be useful in the early detection of metabolic CNS changes in NP-SLE patients with acute onset of new neurological symptoms as well as in the follow-up after treatment to assess presence and changes in metabolic brain injury. However, although there are detectable differences between normal individuals and lupus patients it is currently unclear whether these relate to the acute episode. Future studies are needed comparing NP-SLE patients with active CNS involvement with those inactive disease.


Asunto(s)
Encefalopatías/etiología , Encefalopatías/patología , Encéfalo/patología , Lupus Eritematoso Sistémico/patología , Lupus Eritematoso Sistémico/psicología , Trastornos Psicóticos/etiología , Trastornos Psicóticos/patología , Enfermedad Aguda , Adulto , Encéfalo/fisiología , Encefalopatías/fisiopatología , Estudios de Casos y Controles , Epilepsia/etiología , Epilepsia/patología , Epilepsia/fisiopatología , Femenino , Humanos , Lupus Eritematoso Sistémico/diagnóstico por imagen , Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética , Persona de Mediana Edad , Trastornos Psicóticos/fisiopatología , Cintigrafía , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/patología , Accidente Cerebrovascular/fisiopatología
20.
Ann Hum Genet ; 60(6): 487-98, 1996 11.
Artículo en Inglés | MEDLINE | ID: mdl-9024577

RESUMEN

An algorithm for detecting well-characterised breakpoints in human family data has been developed and implemented as a computer program. The well-established program CRI-Map is used to perform the necessary likelihood analysis and generate the individual chromosomes, and then a set of user-defined parameters is used to detect the breakpoints, sort them by their position and classify them according to their support. A further program produces PostScript figures giving a visual representation of the breakpoints. The programs can be applied to data from human chromosomes, and the resulting breakpoint panels used to place new markers rapidly on to the map by typing only a few key individuals and their ancestors. A service has been established on the World Wide Web for chromosome 9, allowing workers to fill in an on-line form requesting a suitable panel of breakpoints to facilitate the mapping of new markers. A key feature of this approach is that all of the computing is done whilst detecting the breakpoints, after which new markers can be positioned without any need for a computer. CROSSFIND has been used to generate all the meiotic breakpoint panels shown in the preceding paper by members of the Eurogem Collaboration (Cox et al 1996).


Asunto(s)
Sistemas de Administración de Bases de Datos , Meiosis/genética , Algoritmos , Fragilidad Cromosómica , Mapeo Cromosómico , Genotipo , Humanos , Funciones de Verosimilitud
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