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1.
Vox Sang ; 118(9): 730-737, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37439150

RESUMEN

BACKGROUND AND OBJECTIVES: Room temperature-stored platelets (RTPs) maximize platelet viability but limit shelf life. The aims of this study were to investigate the impact of donor variability on cold-stored platelets (CSPs) and RTP, to determine whether RTP quality markers are appropriate for CSP. MATERIALS AND METHODS: Double platelet donations (n = 10) were collected from consented regular male donors stored in 100% plasma. A full blood count, donor age, weight, height and body mass index (BMI) were collected at the time of donation. Platelet donations were split equally into two bags, and assigned to non-agitated CSP or agitated RTP. The quality and function of platelets were assessed throughout the standard 7 days of storage and at expiry (day 8). Non-parametric statistical analyses were used to analyse results given the small sample size. RESULTS: As expected, there were significant differences between CSP and RTP throughout storage including a reduction in CSP concentration as well as a loss of swirling. Furthermore, a significant increase in CSP exhibiting activation and apoptotic markers was observed. Platelet concentrations were further impacted by donor BMI, and donors with the highest BMI (>29) had the lowest platelet concentration and activation response at the end of CSP storage. CONCLUSION: Platelet quality and functionality play a vital role in transfusion outcomes; however, blood components are inherently variable. This study demonstrated, for the first time, the specific impact of donor BMI on CSP quality and function and highlights the requirement for novel quality markers for assessing CSPs.


Asunto(s)
Plaquetas , Frío , Masculino , Humanos , Plaquetas/fisiología , Transfusión Sanguínea , Donantes de Tejidos , Plasma , Conservación de la Sangre/métodos
2.
Vox Sang ; 117(5): 671-677, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35023205

RESUMEN

BACKGROUND AND OBJECTIVES: In many countries, whole blood (WB) donations with collection times between 12 and 15 min are not allowed to be used for platelet concentrates (PC). Since the development of guidelines, many process-related changes have been introduced. We aimed to determine the effect of WB with long collection times on PC quality. MATERIALS AND METHODS: Five participating centres tested buffy coat (BC)-derived PC in platelet additive solution type E prepared from only WB collections lasting <12 min (control) versus similar PC including one BC from a collection lasting >12 min (study group, n = 8). One centre produced platelet-rich plasma (PRP)-derived PC from single donations (<10 or >12 min). All PC were stored at 22 ± 2°C and sampled on Days 1, 6 and 8 post-collection for in vitro quality determination. RESULTS: Average collection time was significantly longer in the study group compared to controls (8.9 ± 2.6 vs. 7.3 ± 1.3 min, p < 0.001). There were no differences in volume, platelet concentration, basal CD62P expression, soluble-CD62P and CCL5 levels, or nucleotide content between the groups. Stimulation with TRAP-6 resulted in comparable levels of cell surface CD62P. On Day 8, all PC fulfilled requirements for pH. The findings from single PRP-derived PC centre were similar. CONCLUSION: PC with one BC and single PRP derived from collections lasting >12 min had equivalent in vitro quality to controls during storage. This study provides evidence that 12-15 min donations should not be excluded for PC preparation and justifies to readdress the guidelines to <15 min instead of <12 min of collection in line with current practice in some countries.


Asunto(s)
Donantes de Sangre , Plasma Rico en Plaquetas , Plaquetas , Conservación de la Sangre , Humanos
3.
Scand J Med Sci Sports ; 32(2): 313-323, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34618984

RESUMEN

Research suggests that people's perceptions of the typical physical activity behaviors of others-descriptive norms-shape their own physical activity. However, prior work has primarily used cross-sectional designs, focused on people's physical activity intentions or self-reported overall physical activity, and failed to attend to how the normative referent affects the norm-behavior relationship. In a pre-registered experiment, we manipulated the descriptive norm to explore its effect on perceived exertion during, and objectively assessed performance on, an exercise (running) task. We also measured the strength of participants' social identification as a member of the norm reference group as a potential moderator. Following a baseline trial, participants (N = 78) were either told that their baseline score on the running task was below average (high norm condition) or above average (low norm condition) compared to members of the reference group. Participants in both conditions tended to perform better in Trial 2 than Trial 1. However, participants in the high norm condition improved their performance significantly (2.5 times) more than participants in the low norm condition. Social identification moderated the effect of the norm manipulation on perceived exertion. High identifiers tended to exert themselves less than low identifiers during Trial 2 if they were told they were above average, whereas if told they were below average, high identifiers exerted themselves slightly more than low identifiers. Results provide evidence that descriptive norm messages can improve people's performance on physically demanding tasks, and indicate that descriptive physical activity norms may be more influential when the norm reference group is subjectively meaningful. Opportunities to fruitfully deploy norm messages in applied contexts are discussed.


Asunto(s)
Esfuerzo Físico , Identificación Social , Estudios Transversales , Humanos , Aptitud Física , Normas Sociales
4.
Dev Psychol ; 57(6): 976-990, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34424014

RESUMEN

We investigated whether the developmental emergence of episodic future thinking (EFT) is associated with performance on a type of delay of gratification task: a delay choice task that involved choosing between a small reward now or a larger reward the next day. In Study 1, 4- to 5-year-olds' (N = 99) EFT as measured by a tool saving task was significantly associated with performance on the delay choice task, but this was not the case for other EFT measures. Study 2 compared the performance of 4- to 5-year-olds (N = 130) on the delay choice task when cued to think about either a future, past, or habitual event versus a no-cue baseline. Overall, cuing impaired performance on the delay choice task. Although EFT does show a relation to performance in a delay choice task in preschoolers, deliberately engaging in thought about future events may be too taxing in young children to reliably enhance the ability to make future-oriented decisions. (PsycInfo Database Record (c) 2021 APA, all rights reserved).


Asunto(s)
Recompensa , Pensamiento , Niño , Preescolar , Señales (Psicología) , Toma de Decisiones , Predicción , Humanos
5.
J Exp Psychol Gen ; 148(2): 272-288, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30058823

RESUMEN

A number of striking temporal asymmetries have been observed in the way that adults think about the past and the future: experiences in the future tend to be more valued than those in the past, feel closer in subjective time, and elicit stronger emotions. Three studies explored the development of these temporal asymmetries for the first time with children and adolescents. Evidence of past/future asymmetry in subjective time emerged from 4 to 5 years of age. Evidence of past/future asymmetry in emotion was clearly observable from 6 to 7 years of age. Evidence of past/future asymmetry in value emerged latest in development and was uncorrelated with judgments of emotion and subjective distance at all ages. We consider the underlying causes of these asymmetries, and discuss the potential relations among them. (PsycINFO Database Record (c) 2019 APA, all rights reserved).


Asunto(s)
Emociones/fisiología , Desarrollo Humano/fisiología , Imaginación/fisiología , Memoria Episódica , Pensamiento/fisiología , Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , Masculino , Tiempo , Adulto Joven
6.
Transfusion ; 58(4): 917-926, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29341199

RESUMEN

BACKGROUND: There are few studies investigating the effect of irradiation on red blood cells (RBCs) during storage. This study analyzed changes in in vitro quality of RBCs irradiated at several points during storage with the aim of providing evidence to support current maximum pre- and postirradiation storage limits. STUDY DESIGN AND METHODS: Each of seven participating centers produced four pools of 7 standard RBC units (SAGM, AS-3, or PAGGSM), which were then split back into 7 units. All units in a pool were from sex-matched blood donors. Every week during 6 weeks of refrigerated storage, 1 unit was irradiated, while 1 unit was not irradiated (control). Units were tested weekly for biochemical variables, morphology, and mechanical fragility. RESULTS: The earlier during storage that units were irradiated, the higher the hemolysis and K+ at end of storage. Irrespective of the timing of irradiation, there was a rapid increase in extracellular K+ , followed by a more gradual increase in hemolysis. ATP levels decreased faster in irradiated units and were reduced below accepted values if irradiated early. Irradiated female RBCs had an absolute lower hemolysis and K+ level compared to male RBCs at all time points. CONCLUSIONS: The method of blood component manufacturing determined the absolute levels of hemolysis and potassium in irradiated and nonirradiated units, but did not influence the effect that timing of irradiation had on the in vitro quality characteristics. This study provides support for the current Council of Europe guidelines on the time limitations for the irradiation of RBCs.


Asunto(s)
Conservación de la Sangre/métodos , Eritrocitos/efectos de la radiación , Rayos gamma , Caracteres Sexuales , Inactivación de Virus , Adenina , Adulto , Recolección de Muestras de Sangre/métodos , Citratos , Europa (Continente) , Líquido Extracelular/química , Femenino , Glucosa , Guanosina , Hemólisis , Humanos , Técnicas In Vitro , Masculino , Manitol , Potasio/sangre , Guías de Práctica Clínica como Asunto , Control de Calidad , Cloruro de Sodio , Factores de Tiempo
7.
Am J Public Health ; 108(3): 343-348, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29346005

RESUMEN

Social media (SM) offer huge potential for public health research, serving as a vehicle for surveillance, delivery of health interventions, recruitment to trials, collection of data, and dissemination. However, the networked nature of the data means they are riddled with ethical challenges, and no clear consensus has emerged as to the ethical handling of such data. This article outlines the key ethical concerns for public health researchers using SM and discusses how these concerns might best be addressed. Key issues discussed include privacy; anonymity and confidentiality; authenticity; the rapidly changing SM environment; informed consent; recruitment, voluntary participation, and sampling; minimizing harm; and data security and management. Despite the obvious need, producing a set of prescriptive guidelines for researchers using SM is difficult because the field is evolving quickly. What is clear, however, is that the ethical issues connected to SM-related public health research are also growing. Most importantly, public health researchers must work within the ethical principles set out by the Declaration of Helsinki that protect individual users first and foremost.


Asunto(s)
Investigación sobre Servicios de Salud/ética , Salud Pública/métodos , Medios de Comunicación Sociales , Confidencialidad , Humanos , Consentimiento Informado , Privacidad , Proyectos de Investigación
8.
N Engl J Med ; 361(3): 264-70, 2009 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-19605831

RESUMEN

BACKGROUND: An ingestible capsule consisting of an endoscope equipped with a video camera at both ends was designed to explore the colon. This study compared capsule endoscopy with optical colonoscopy for the detection of colorectal polyps and cancer. METHODS: We performed a prospective, multicenter study comparing capsule endoscopy with optical colonoscopy (the standard for comparison) in a cohort of patients with known or suspected colonic disease for the detection of colorectal polyps or cancer. Patients underwent an adapted colon preparation, and colon cleanliness was graded from poor to excellent. We computed the sensitivity and specificity of capsule endoscopy for polyps, advanced adenoma, and cancer. RESULTS: A total of 328 patients (mean age, 58.6 years) were included in the study. The capsule was excreted within 10 hours after ingestion and before the end of the lifetime of the battery in 92.8% of the patients. The sensitivity and specificity of capsule endoscopy for detecting polyps that were 6 mm in size or bigger were 64% (95% confidence interval [CI], 59 to 72) and 84% (95% CI, 81 to 87), respectively, and for detecting advanced adenoma, the sensitivity and specificity were 73% (95% CI, 61 to 83) and 79% (95% CI, 77 to 81), respectively. Of 19 cancers detected by colonoscopy, 14 were detected by capsule endoscopy (sensitivity, 74%; 95% CI, 52 to 88). For all lesions, the sensitivity of capsule endoscopy was higher in patients with good or excellent colon cleanliness than in those with fair or poor colon cleanliness. Mild-to-moderate adverse events were reported in 26 patients (7.9%) and were mostly related to the colon preparation. CONCLUSIONS: The use of capsule endoscopy of the colon allows visualization of the colonic mucosa in most patients, but its sensitivity for detecting colonic lesions is low as compared with the use of optical colonoscopy. (ClinicalTrials.gov number, NCT00604162.)


Asunto(s)
Endoscopía Capsular , Pólipos del Colon/diagnóstico , Colonoscopía , Neoplasias Colorrectales/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Endoscopios en Cápsulas , Femenino , Humanos , Mucosa Intestinal/anatomía & histología , Mucosa Intestinal/patología , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Sensibilidad y Especificidad , Adulto Joven
9.
J Pediatr Gastroenterol Nutr ; 49(4): 417-23, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19543117

RESUMEN

OBJECTIVES: Peutz-Jeghers syndrome (PJS) in children may present with anaemia, intussusception, or obstruction from an early age and surgery is common. Prophylactic polypectomy may reduce subsequent complications. Traditional barium enterography (BE) has poor sensitivity and requires significant radiation. We compared the performance of capsule endoscopy (CE) with BE in children with PJS. MATERIALS AND METHODS: Children with PJS (ages 6.0-16.5 years) were prospectively recruited and underwent BE followed by CE, each reported by expert reviewers blinded to the alternate modality. Number of "significant" (>10 mm) and total number of polyps were recorded. Child preference was assessed using a visual analogue questionnaire. Definitive findings were assessed at laparotomy or enteroscopy, when performed. RESULTS: There was no significant difference for >10 mm polyp detection. Six polyps were found in 3 children by both modalities: 3 polyps in 2 children at CE, 3 polyps in 1 child at BE (P=0.50). Re-review of 1 CE identified 3 polyps that were missed in 1 child at initial reading. Significantly more <10 mm polyps were identified by CE than BE: 61 vs 6 (P=0.02). CE was significantly more comfortable than BE (median score CE 76 [interquartile range 69-87] vs BE 37 [interquartile range 31-68], P=0.03) and was the preferred investigation in 90% (P=0.02). CONCLUSIONS: CE is a feasible, safe, and sensitive test for small bowel polyp surveillance in children with PJS. It is significantly more comfortable than BE and is the preferred test of most children for future surveillance. There is a learning curve for reporting CE studies in PJS and appropriate training is essential.


Asunto(s)
Endoscopía Capsular/métodos , Pólipos Intestinales/patología , Intestino Delgado/patología , Síndrome de Peutz-Jeghers/patología , Radiografía Abdominal/métodos , Adolescente , Bario , Niño , Femenino , Fluoroscopía/métodos , Humanos , Pólipos Intestinales/diagnóstico por imagen , Intestino Delgado/diagnóstico por imagen , Masculino , Satisfacción del Paciente , Síndrome de Peutz-Jeghers/diagnóstico por imagen , Sensibilidad y Especificidad , Método Simple Ciego
10.
Gastrointest Endosc ; 70(2): 310-6, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19386301

RESUMEN

BACKGROUND: The rapid expansion in use of capsule endoscopy (CE) has led to discussion about training needs and provision. The lesion recognition skills required for CE are ideally suited to computer-based training. OBJECTIVE: The aim of this study was to prospectively evaluate the educational effectiveness of a computer-based CE training and testing module on trainees with varying experience. DESIGN: This was a prospective educational evaluation study. SETTING: Academic endoscopy unit. PATIENTS: This study involved 28 trainees of varying CE experience (medical students, gastroenterology trainees) and 4 CE experts. INTERVENTION: Trainees (medical students and gastroenterology trainees) without CE experience completed a 60-question, computer-based test module consisting of 30-second video clips and multiple-choice questions. Without feedback, trainees then completed a comprehensive, menu-driven, computer-based CE training module. The test module was then completed a second time and feedback was given. Expert performance on the test module was benchmarked by 4 CE experts. MAIN OUTCOME MEASUREMENTS: The first measure was the difference in baseline performance on the test module between trainees and experts (to determine construct validity). The second measure was a change in performance on the test module after training (to determine content validity of the training module). RESULTS: A significant difference was noted in baseline performance (P < .001) among CE experts (mean 73.8% +/- 8.0%), gastroenterology trainees (49.5% +/- 10.9%), and medical students (29.5% +/- 3.3%). Performance improved significantly (P < .001) in both trainee groups after training (gastroenterology trainees' posttraining score 62.1% +/- 7.7%; medical students' 46.7% +/- 6.8%). CONCLUSION: Computer-based learning has a potentially significant role in the development of a training syllabus for CE and in CE accreditation.


Asunto(s)
Endoscopía Capsular , Competencia Clínica , Instrucción por Computador , Estudios Prospectivos
11.
Gastrointest Endosc ; 69(6): 1120-8, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19152909

RESUMEN

BACKGROUND: Capsule endoscopy (CE) is limited by incomplete small-bowel transit and poor view quality in the distal bowel. Currently, there is no consensus regarding the use of bowel purgatives or prokinetics in CE. OBJECTIVE: To evaluate the usefulness of bowel purgatives and prokinetics in small-bowel CE. DESIGN: Prospective single-blind randomized controlled study. SETTING: Academic endoscopy unit. PATIENTS: A total of 150 patients prospectively recruited. INTERVENTION: Patients were randomized to 1 of 4 preparations: "standard" (fluid restriction then nothing by mouth 12 hours before the procedure, water and simethicone at capsule ingestion [S]); "standard" + 10 mg oral metoclopramide before the procedure (M); Citramag + senna bowel-purgative regimen the evening before CE (CS); Citramag + senna + 10 mg metoclopramide before the procedure (CSM). MAIN OUTCOME MEASUREMENTS: Gastric transit time (GTT) and small-bowel transit time (SBTT), completion rates (CR), view quality, and patient acceptability. SECONDARY OUTCOME MEASURES: positive findings, diagnostic yield. RESULTS: No significant difference was noted among groups for GTT (median [minutes] M, CS, and CSM vs S: 17.3, 24.7, and 15.1 minutes vs 16.8 minutes, respectively; P = .62, .18, and .30, respectively), SBTT (median [minutes] M, CS, and CSM vs S: 260, 241, and 201 vs 278, respectively; P = .91, .81, and .32, respectively), or CRs (85%, 85%, and 88% vs 89% for M, CS, and CSM vs S, respectively; P = .74, .74, and 1.00, respectively). There was no significant difference in view quality among groups (of 44: 38, 37, and 40 vs 37 for M, CS, and CSM, vs S, respectively; P = .18, .62, and .12, respectively). Diagnostic yield was similar among the groups. CS and CSM regimens were significantly less convenient (P < .001), and CS was significantly less comfortable (P = .001) than standard preparation. CONCLUSIONS: Bowel purgatives and prokinetics do not improve CRs or view quality at CE, and bowel purgatives reduce patient acceptability.


Asunto(s)
Endoscopía Capsular/métodos , Catárticos/administración & dosificación , Ácido Cítrico/administración & dosificación , Motilidad Gastrointestinal/efectos de los fármacos , Tránsito Gastrointestinal/efectos de los fármacos , Enfermedades Intestinales/diagnóstico , Intestino Delgado , Magnesio/administración & dosificación , Metoclopramida/administración & dosificación , Extracto de Senna/administración & dosificación , Simeticona/administración & dosificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Catárticos/efectos adversos , Esquema de Medicación , Combinación de Medicamentos , Quimioterapia Combinada , Femenino , Humanos , Intestino Delgado/efectos de los fármacos , Magnesio/efectos adversos , Masculino , Metoclopramida/efectos adversos , Persona de Mediana Edad , Premedicación , Estudios Prospectivos , Extracto de Senna/efectos adversos , Simeticona/efectos adversos , Método Simple Ciego , Adulto Joven
12.
Dig Dis Sci ; 54(8): 1672-9, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19034658

RESUMEN

There are no validated training/accreditation guidelines for capsule endoscopy. We assessed the utility of a structured training program on two experienced gastroenterologists and one endoscopy nurse. Validated studies were standardized for difficulty in blocks of three. Trainees completed a standardized data sheet for each study reported (12 studies for the physicians, 22 studies for the nurse). After each block the trainer graded performance and highlighted learning points. Statistical analysis was performed. Physician trainees accurately identified landmarks throughout, while the nurse made errors even at the end of training. Improvement in lesion detection and diagnostic accuracy improved in the nurse, but in only one of the physician trainees, highlighting the variability in learning curves. Overall performance improved in all trainees but was most marked for the nurse trainee (correlation coefficient 0.41, P = 0.06). Improvements in lesion recognition and diagnosis can be demonstrated in senior trainees and nurses following a structured training program; however, there is considerable variability.


Asunto(s)
Endoscopía Capsular/normas , Competencia Clínica/normas , Educación/métodos , Educación/normas , Acreditación , Guías como Asunto , Humanos , Cuerpo Médico/educación , Proyectos Piloto , Estudios Prospectivos
14.
Dig Dis Sci ; 53(10): 2732-8, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18320313

RESUMEN

INTRODUCTION: The patency capsule may prevent capsule retention in high-risk patients. However data on its use in routine clinical practice is limited. METHODS: Patients referred to our institution between Feb-04 and Jan-07 were reviewed. The following data was collected: presenting symptoms; medical/surgical history; medication; radiology; patency/video capsule result; subsequent investigations; clinical outcomes. RESULTS: 373 patients were referred. In 315 (84%) 'low-risk' patients (no patency capsule): delayed transit occurred in three, with no cases of capsule retention. In 58 (16%) 'high risk' patients (patency capsule): asymptomatic retention occurred in eight, all with pathology despite normal prior barium studies in six; in four cases patency location was incorrectly assessed radiologically, leading to video capsule retention and surgery in one. DISCUSSION: Most patients can safely undergo capsule endoscopy without a patency capsule. The patency capsule appears safe and is indicative of pathology when retained. Assessment of patency capsule location post ingestion can be difficult, and if barium radiology is equivocal a limited abdominal computed tomography (CT) scan is suggested.


Asunto(s)
Endoscopios en Cápsulas/efectos adversos , Endoscopios en Cápsulas/estadística & datos numéricos , Endoscopía Capsular/métodos , Anciano , Bario , Seguridad de Equipos , Femenino , Tránsito Gastrointestinal/fisiología , Humanos , Obstrucción Intestinal/diagnóstico por imagen , Obstrucción Intestinal/epidemiología , Obstrucción Intestinal/fisiopatología , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Estudios Retrospectivos , Factores de Riesgo , Tomografía Computarizada por Rayos X
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