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BACKGROUND: Immediate hypersensitivity reactions occurring during anesthesia are classified as allergic when skin tests and mast cell tryptase are positive and as nonallergic when negative results are obtained. Cysteinyl leukotrienes (cysLTs) are potent mediators synthesized by mast cell and eosinophil that induce bronchial constriction. They could play a role in hypersensitivity reactions. METHODS: cysLT C4, D4, and E4 concentrations were measured by a competition immunoassay in serial plasma samples obtained prospectively from 21 anesthetized controls and retrospectively from 34 patients who reacted at induction of anesthesia (24 with allergic and 10 with nonallergic reactions). RESULTS: In controls, the median (interquartile range) cysLT concentration was 0.83 (0.69 to 1.02) µg/l before anesthesia and was unchanged 30 min, 6 h, and 24 h afterward. In the patients with allergic reactions, the values were highly increased 30 to 60 min after the reaction (17.9 [7.8 to 36.0] µg/l), while the patients with nonallergic reactions had less increased values (7.3 [3.0 to 11.5] µg/l). The difference between the three groups was significant (P < 0.0001). Increased values persisted during the 24 h of observation. Concentrations were significantly higher in patients with bronchospasm (P = 0.016). CONCLUSIONS: cysLTs appear to be an important mediator of allergic and nonallergic immediate hypersensitivity reactions. These findings might open a new field for management of patients with hypersensitivity reactions, especially nonallergic ones.
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Anestesia/efectos adversos , Cisteína/sangre , Hipersensibilidad a las Drogas/sangre , Hipersensibilidad Inmediata/sangre , Leucotrienos/sangre , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios RetrospectivosAsunto(s)
Anafilaxia , Histamina , Anafilaxia/diagnóstico , Anafilaxia/etiología , Quimasas , Liberación de Histamina , Humanos , Mastocitos , TriptasasRESUMEN
BACKGROUND: The diagnosis of acute life-threatening allergic reactions during anesthesia relies on clinical signs, histamine and/or tryptase measurements, and allergic testing. In patients who die after the reaction, skin tests cannot be performed, and the effect of resuscitation manoeuvres on mediator concentrations is unknown. The authors compared plasma histamine and tryptase concentrations in patients with severe allergic reactions during anesthesia with those measured in patients with shock due to other causes. METHODS: Patients with life-threatening allergic reactions were retrieved from a previous database (Group ALLERGY). All had positive allergy tests to administered agents. Patients with severe septic/cardiogenic shock or cardiac arrest (Group CONTROL) had histamine and tryptase measurements during resuscitation manoeuvres. Receiver operating characteristics curves were built to calculate the optimal mediator thresholds differentiating allergic reactions from others. RESULTS: One hundred patients were included, 75 in Group ALLERGY (cardiovascular collapse, 67; cardiac arrest, 8) and 25 in Group CONTROL (shock, 11; cardiac arrest, 14). Mean histamine and tryptase concentrations remained unchanged throughout resuscitation in Group CONTROL and were significantly higher in Group ALLERGY. The optimal thresholds indicating an allergic mechanism were determined as 6.35 nmol/l for histamine (sensitivity: 90.7% [95% CI, 81.7 to 96.1]; specificity: 91.7% [73.0 to 98.9]) and 7.35 µg/l for tryptase (sensitivity: 92% [83.4 to 97.0]; specificity: 92% [73.9 to 99.0]). CONCLUSIONS: Resuscitation manoeuvres by themselves did not modify mediator concentrations. Virtually all life-threatening reactions during anesthesia associated with mediator concentrations exceeding the thresholds were allergic events. These findings have potential forensic interest when a patient dies during anesthesia.
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Anafilaxia/diagnóstico , Anestesia/efectos adversos , Hipersensibilidad a las Drogas/diagnóstico , Paro Cardíaco/diagnóstico , Histamina/sangre , Choque/diagnóstico , Triptasas/sangre , Adulto , Anciano , Anafilaxia/sangre , Área Bajo la Curva , Hipersensibilidad a las Drogas/sangre , Femenino , Paro Cardíaco/sangre , Liberación de Histamina/efectos de los fármacos , Humanos , Complicaciones Intraoperatorias/sangre , Complicaciones Intraoperatorias/diagnóstico , Masculino , Persona de Mediana Edad , Curva ROC , Tamaño de la Muestra , Choque/sangreRESUMEN
Family-driven collaboration is fundamental to developing a new model of health care and eliminating fragmented services in mental health. The province of Québec (Canada) recently undertook major transformations of its mental health care system. These transformations represent an opportunity to improve collaboration between families and health care practitioners and to understand which factors facilitate this collaboration. This article describes how families and decision makers perceive collaboration in the context of a major transformation of mental health services and identifies the factors that facilitate and hinder family collaboration.
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Cuidadores/psicología , Conducta Cooperativa , Toma de Decisiones , Reforma de la Atención de Salud , Trastornos Mentales/enfermería , Servicios de Salud Mental , Relaciones Profesional-Familia , Cuidadores/educación , Confidencialidad , Comportamiento del Consumidor , Enfermería de la Familia , Femenino , Grupos Focales , Accesibilidad a los Servicios de Salud , Humanos , Relaciones Interprofesionales , Cuidados a Largo Plazo/psicología , Masculino , Persona de Mediana Edad , Transferencia de Pacientes , Atención Dirigida al Paciente , Quebec , Apoyo SocialRESUMEN
Background: Integrated Primary Care Teams (IPCTs) have four key characteristics (intensive interdisciplinary practice; advanced nursing practice with an expanded role; group practice; increased proximity and availability) aimed at strengthening primary care in Quebec, Canada. The purpose of this paper is to examine the care experience over time of patients who have an IPCT as their primary source of care. Methods: We used a quasi-experimental longitudinal design based on a pre-and-post administered survey at a 2-year interval without a control group. We measured patient-reported accessibility, continuity, comprehensiveness, responsiveness and outcomes of care. Results: Results showed that patients who were newly registered with an IPCT had a significant increase in reported care experience, whereas patients who have been registered with an IPCT for 2 years prior to the first round of data collection had already high reported care experience that was maintained over time. Moreover, linear regression models showed statistically significant different increases in the dimensions of care experience by site and patients' characteristics. Conclusions: Our results suggest that the IPCT model is tailored to the needs of its target populations, resulting in improved Patient Reported Experience Measures. These results imply that broader implementation of innovative and flexible community-based care models should be considered by policymakers.
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BACKGROUND: Neuromuscular blocking agents (NMBA) are responsible for most immediate hypersensitivity reactions during anesthesia, as a result of the presence of a quaternary ammonium ion. The aim of this study was to evaluate the diagnostic performance of a commercial immunoglobulin E (IgE) test (quaternary ammonium morphine [QAM]) for diagnosing sensitivity to NMBA. METHODS: We tested 168 patients exposed to NMBAs during anesthesia. Of those patients, 54 had an uneventful procedure and 114 had immediate hypersensitivity reactions, and 57 patients had positive skin tests to the administered NMBA, whereas 57 had negative skin tests. Specific IgE concentrations determined with the QAM method based on a morphine solid phase were compared with those obtained with a recommended experimental method with a choline solid phase. RESULTS: For the QAM test, a 0.35 kUA/l positivity cutoff was chosen from the receiver operating characteristics curve. QAM-specific IgE was found in 84.2% of skin test-positive reactors (80.7% with the recommended method; no significant difference), and binding was inhibited by the culprit NMBA in 80% of cases. The frequency of QAM-specific IgE positivity was significantly higher in skin test-negative reactors (24.6%) than in controls (9.3%), suggesting NMBA sensitivity. CONCLUSION: Sensitivity of the QAM test (84.2%), together with its simplicity and suitability for routine laboratory use, makes it a valuable tool, in conjunction with skin tests, for diagnosing NMBA sensitivity in patients who react after NMBA injection. The QAM test is of particular interest when skin tests are not available or not reliable or give results poorly compatible with mediator release or clinical features.
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Hipersensibilidad a las Drogas/diagnóstico , Hipersensibilidad Inmediata/diagnóstico , Inmunoglobulina E/inmunología , Bloqueantes Neuromusculares/efectos adversos , Hipersensibilidad a las Drogas/sangre , Hipersensibilidad a las Drogas/etiología , Femenino , Humanos , Hipersensibilidad Inmediata/sangre , Hipersensibilidad Inmediata/inducido químicamente , Inmunoglobulina E/sangre , Masculino , Persona de Mediana Edad , Morfina/inmunología , Bloqueantes Neuromusculares/inmunología , Compuestos de Amonio Cuaternario/inmunología , Curva ROC , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y Especificidad , Pruebas Cutáneas/métodos , Pruebas Cutáneas/estadística & datos numéricosRESUMEN
The aim of this study was to investigate the relationships between 4 dimensions of the psychosocial work environment (psychological demands, decision latitude, social support, and effort-reward) among health care professionals as well as their psychological distress during a reorganization process. A correlational descriptive design was used for this quantitative study. A total of 159 health care professionals completed the questionnaire at T1, and 141 at T2. First, before the work reorganization, effort-reward imbalance was the sole variable of the psychological work environment that significantly predicted psychological distress. Second, the high overall level of psychological distress increased during the process of organizational change (from T1 to T2). Finally, effort-reward imbalance, high psychological demands, and low decision latitude were all significant predictors of psychological distress at T2, during the organizational change. In conclusion, to reduce the expected negative outcomes of restructuring on health care practitioners, managers could increase the number of opportunities for rewards, carefully explain the demands, and clarify the tasks to be performed by each of the employees to reduce their psychological burden and increase their perceptions of autonomy.
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Personal de Salud/psicología , Innovación Organizacional , Estrés Psicológico/etiología , Lugar de Trabajo/psicología , Femenino , Administración Hospitalaria , Humanos , Satisfacción en el Trabajo , Masculino , Persona de Mediana Edad , Quebec , Análisis de Regresión , Factores de Riesgo , Apoyo Social , Factores Socioeconómicos , Estrés Psicológico/psicología , Encuestas y Cuestionarios , Lugar de Trabajo/organización & administraciónRESUMEN
Quantum computation by non-Abelian Majorana zero modes (MZMs) offers an approach to achieve fault tolerance by encoding quantum information in the non-local charge parity states of semiconductor nanowire networks in the topological superconductor regime. Thus far, experimental studies of MZMs chiefly relied on single electron tunneling measurements, which lead to the decoherence of the quantum information stored in the MZM. As a next step towards topological quantum computation, charge parity conserving experiments based on the Josephson effect are required, which can also help exclude suggested non-topological origins of the zero bias conductance anomaly. Here we report the direct measurement of the Josephson radiation frequency in indium arsenide nanowires with epitaxial aluminium shells. We observe the 4π-periodic Josephson effect above a magnetic field of ≈200 mT, consistent with the estimated and measured topological phase transition of similar devices.
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BACKGROUND: Iodinated and gadolinium-based contrast media (ICM; GBCM) induce immediate hypersensitivity (IH) reactions. Differentiating allergic from non-allergic IH is crucial; allergy contraindicates the culprit agent for life. We studied frequency of allergic IH among ICM or GBCM reactors. METHODS: Patients were recruited in 31 hospitals between 2005 and 2009. Clinical symptoms, plasma histamine and tryptase concentrations and skin tests were recorded. Allergic IH was diagnosed by intradermal tests (IDT) with the culprit CM diluted 1:10, "potentially allergic" IH by positive IDT with pure CM, and non-allergic IH by negative IDT. FINDINGS: Among 245 skin-tested patients (ICMâ¯=â¯209; GBCMâ¯=â¯36), allergic IH to ICM was identified in 41 (19.6%) and to GBCM in 10 (27.8%). Skin cross-reactivity was observed in 11 patients with ICM (26.8%) and 5 with GBCM (50%). Allergy frequency increased with clinical severity and histamine and tryptase concentrations (pâ¯<â¯0.0001). Cardiovascular signs were strongly associated with allergy. Non-allergic IH was observed in 152 patients (62%) (ICM:134; GBCM:18). Severity grade was lower (pâ¯<â¯0.0001) and reaction delay longer (11.6 vs 5.6â¯min; pâ¯<â¯0.001). Potentially allergic IH was diagnosed in 42 patients (17.1%) (ICM:34; GBCM:8). The delay, severity grade, and mediator release were intermediate between the two other groups. INTERPRETATION: Allergic IH accounted for < 10% of cutaneous reactions, and > 50% of life-threatening ones. GBCM and ICM triggered comparable IH reactions in frequency and severity. Cross-reactivity was frequent, especially for GBCM. We propose considering skin testing with pure contrast agent, as it is more sensitive than the usual 1:10 dilution criteria.
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The diagnosis of a perioperative allergic reaction is based on clinical features associated with a suggestive timeline, the exclusion of other diagnoses, elevated concentrations of degranulation markers (histamine, tryptase), and positive allergy assessments (skin tests, specific IgE). After initiating appropriate treatment, the anesthesiologist should take blood samples to measure histamine and tryptase concentrations just after the reaction and repeat them 1-2hours later to validate the diagnosis of immediate hypersensitivity. A delayed measurement of basal tryptase is useful to rule out mastocytosis and to interpret moderate tryptase levels. The anesthesiologist must inform the patient of the reaction to obtain adhesion and consent to subsequent investigations and must record the timing of the reaction and of the blood sampling, the possible causal agents, and the treatment administered. These data must be shared with the laboratory and the allergist. An adverse drug reaction report must be filed. The gold standard for allergy assessment is skin testing. These tests should be done in an appropriate facility, with experienced staff and in compliance with current guidelines. Specific IgE assays and cellular assays can help when clinical features and skin tests are discordant. Provocation tests are sometimes required. After allergy assessment, the safest protocol for subsequent anesthesia is determined in collaboration with the anesthesiologist. The patient must be informed and carry an allergy alert card.
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Hipersensibilidad Inmediata/diagnóstico , Complicaciones Intraoperatorias/diagnóstico , Árboles de Decisión , Pruebas Diagnósticas de Rutina , Humanos , QuirófanosRESUMEN
Immediate reactions to iodinated contrast media (ICM) resembles anaphylaxis. The recent literature demonstrates that histamine is released in vivo, with a peak concentration correlating within the severity grade of the reaction. Mast cells participate in severe reactions, as shown by several authors through the release of tryptase. In patients with severe reactions, intradermal testing with immediate reading appear positive to the culprit ICM, confirming an immune mechanism. For further procedures, a strict avoidance of the culprit ICM must be observed. The injection of another ICM giving negative skin tests has proved safe in a few patients.
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Medios de Contraste/efectos adversos , Hipersensibilidad a las Drogas/diagnóstico , Hipersensibilidad a las Drogas/metabolismo , Mediadores de Inflamación/metabolismo , Liberación de Histamina , Humanos , Pruebas CutáneasRESUMEN
Electrostatic gates are of paramount importance for the physics of devices based on high-mobility two-dimensional electron gas (2DEG) since they allow depletion of electrons in selected areas. This field-effect gating enables the fabrication of a wide range of devices such as, for example, quantum point contacts (QPC), electron interferometers and quantum dots. To fabricate these gates, processing is usually performed on the 2DEG material, which is in many cases detrimental to its electron mobility. Here we propose an alternative process which does not require any processing of the 2DEG material other than for the ohmic contacts. This approach relies on processing a separate wafer that is then mechanically mounted on the 2DEG material in a flip-chip fashion. This technique proved successful to fabricate quantum point contacts on both GaAs/AlGaAs materials with both moderate and ultra-high electron mobility.
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The aim of the project was to assess the relationship between zinc status and bone mineralisation in pre-menarcheal adolescent girls. One hundred and thirty-nine healthy pre-menarcheal girls (Tanner pubic hair stage < or = 4), aged 12.4 +/- 1.0 years, had two visits at an interval of 2 years. Serum and urine zinc concentrations (Zn S; Zn U; Zn U/ creatinine), insulin-like growth factor 1 (IGF-I), and markers of bone turn-over, i.e. osteocalcin and parathormone (PTH), concentrations were measured at the first visit. Lumbar (L2-L4) bone mineral content and density (BMC, BMD) were measured at both visits. BMC and BMD and their increase at the follow-up after 2 years were compared with biochemical data by multiple regression. The stage of puberty was added as a covariable in the analysis. At the first visit, a significant correlation was found between sexual maturity and initial BMC, BMD, height, weight, and IGF-I. Zn S was negatively correlated with osteocalcin. Zn U showed a positive correlation with BMC, BMD, IGF-I, height, weight, and PTH. At the second visit, sexual maturity showed a positive correlation with BMD and weight increments and a negative one with BMC and height gains. Zn S was significantly related with BMD increase. These correlations suggest that zinc plays a role in normal growth and bone mineralisation during puberty onset.
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Calcificación Fisiológica/fisiología , Zinc/sangre , Zinc/orina , Adolescente , Animales , Biomarcadores , Densidad Ósea , Femenino , Humanos , Análisis de Regresión , Maduración Sexual/fisiologíaRESUMEN
Hypersensitivity reactions are a classic side effect of cetuximab. We report the cases of three patients who developed life-threatening hypersensitivity to cetuximab, which could have been predicted by assessing the concentration of serum anticetuximab immunoglobulin (Ig)E. The anticetuximab IgE concentration could be an interesting test to predict which patients are at risk of experiencing severe hypersensitivity reactions to cetuximab.
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Cetuximab, a chimeric mouse-human IgG1 monoclonal antibody against the epidermal growth factor receptor, has proven effective in the treatment of metastatic colorectal cancer and squamous cell carcinoma of the head and neck. However, a high incidence of immediate hypersensitivity reactions (HSR) to cetuximab after the first infusion has been observed. We have developed a test for identification of patients likely to show treatment-related HSR to cetuximab. An enzyme-linked immunosorbent assay (ELISA) for detecting anti-cetuximab IgEs was developed and tested on serum samples collected from cancer patients before start of cetuximab treatment, and from healthy blood donors. Similar levels of anti-cetuximab IgE were detected in pre-treatment patient sera (24/92, 26.1%) and sera from healthy blood donors (33/117, 28.2%). HSR were observed in 14 out of the 92 patients (15.2%), and 8 of these (57.1%) were grade 3-4. Anti-cetuximab IgEs were detected in 7/8 of the patients (87.5%) with severe HSRs as compared with 14/78 patients (17.9%) with no HSR (p=0.0002). Predictive value of the anti-cetuximab IgE test for HSR events of grades 3-4 was calculated using Receiver Operating Characteristics analysis. With a cut-off value of 29 arbitrary units for the anti-cetuximab IgE, the ELISA test showed a sensitivity of 87.5%, specificity of 82.1%, positive predictive value of 33.3% and negative predictive value of 98.5%. Anti-cetuximab IgE ELISA detection could be a valuable tool to help the physician anticipate an anaphylaxis episode following cetuximab infusion and opt for a suitable alternative treatment.
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Anafilaxia/inducido químicamente , Anticuerpos Antiidiotipos/sangre , Anticuerpos Monoclonales/efectos adversos , Hipersensibilidad Inmediata/diagnóstico , Neoplasias/terapia , Adulto , Anciano , Anciano de 80 o más Años , Anafilaxia/prevención & control , Animales , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales Humanizados , Cetuximab , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Hipersensibilidad Inmediata/inmunología , Hipersensibilidad Inmediata/fisiopatología , Masculino , Ratones , Persona de Mediana Edad , Neoplasias/inmunología , Valor Predictivo de las Pruebas , Riesgo , Sensibilidad y EspecificidadRESUMEN
OBJECTIVES: To investigate the pathomechanisms involved in cases of immediate hypersensitivity reactions occurring after the administration of iodinated contrast media. MATERIALS AND METHODS: Patients having presented clinical signs of immediate hypersensitivity suggesting allergy after iodinated contrast medium were investigated. Histamine and tryptase concentrations were measured, and/or skin tests were performed. Patients with positive skin tests to the culprit contrast agent were classified as IgE-mediated allergic hypersensitivity (Group I) and patients with negative skin tests as non-allergic hypersensitivity (Group II). RESULTS: 38 patients were included. Most reactions appeared after non-ionic (n = 32). Reactions were more frequently severe following ionic than non-ionic (p = 0.014). Skin testing was not performed in 11 patients. Skin tests with the culprit contrast agent were negative in 26% of the patients (Group II, n = 7) whereas they were found positive with the contrast agent in 73% of the patients (Group I, n = 19). Latex-induced reaction was diagnosed in one patient, and was consequently excluded from the cohort. In Group I, the frequency of cross-reactivity with the other commercialized iodinated contrast media was low (7%). Cardiovascular signs were present in Group I (52.6%, n = 10), and absent in Group II (p = 0.023). Histamine and tryptase concentrations were higher in patients who had cardiovascular signs (p < 0.02). CONCLUSION: Immediate reactions with clinical signs suggesting allergy along with positive skin tests with the administered contrast agent confirm immediate allergic hypersensitivity (anaphylaxis) to this agent. Consequently, the culprit contrast agent should be definitely avoided as well as cross-reactive ICM in order to prevent further recurrences.