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1.
BMC Med Res Methodol ; 21(1): 163, 2021 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-34376151

RESUMEN

BACKGROUND: The COVID-19 pandemic is currently a severe challenge for healthcare workers, with a considerable impact on their mental health. In order to focus preventive and rehabilitation measures it's fundamental to identify risk factors of such psychological impairment. We designed an observational longitudinal study to systematically examine the psychological wellbeing of all employees in a large University Hospital in Italy, using validated psychometric scales in the context of the occupational physician's health surveillance, in collaboration with Psychiatric Unit. METHODS: The study started after ethical approval in August 2020. For each worker, the psychological wellbeing is screened in two steps. The first level questionnaire collects sociodemographic characteristics, personal and occupational COVID-19 exposure, worries and concerns about COVID-19, general psychological discomfort (GHQ-12), post-traumatic stress symptoms (IES-R) and anxiety (GAD-7). Workers who score above the cut-off in at least one scale are further investigated by the second level questionnaire composed by PHQ-9, DES-II and SCL-90. If second level shows psychological impairments, we offer individual specialist treatment (third level). We plan to follow-up all subjects to monitor symptoms and possible chronicization; we aim to investigate potential risk factors through univariate analysis and multivariate logistic regressions. RESULTS: Preliminary results refer to a sample of 550 workers who completed the multi-step evaluation from August to December 2020, before vaccination campaign started. The participation rate was 90%. At first level screening, 39% of the subjects expressed general psychological discomfort (GHQ-12), 22% post-traumatic stress symptoms (IES-R), and 21% symptoms of anxiety (GAD-7). Women, nurses, younger workers, subjects with COVID-19 working exposure and with an infected family member showed significantly higher psychological impairment compared to colleagues. After the second level screening, 12% and 7% of all workers showed, respectively, depressive and dissociative symptoms; scorings were significantly associated with gender and occupational role. We are currently extending sample size and evaluating subjects over a period of further 12 months. CONCLUSIONS: The possibility to perform a systematic follow-up of psychological wellbeing of all hospital workers, directly or indirectly exposed to pandemic consequences, constitutes a unique condition to detect individual, occupational, and non-occupational risk factors for psychological impairment in situations of prolonged stress, as well as variables associated with symptoms chronicization.


Asunto(s)
COVID-19 , Pandemias , Ansiedad/diagnóstico , Ansiedad/epidemiología , Depresión , Femenino , Personal de Salud , Hospitales Universitarios , Humanos , Estudios Longitudinales , Salud Mental , SARS-CoV-2 , Encuestas y Cuestionarios
2.
Pacing Clin Electrophysiol ; 29(12): 1326-33, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17201838

RESUMEN

BACKGROUND: His Bundle (HB) pacing is a valid alternative to right ventricular pacing for patients with preserved His-ventricle conduction who are candidates for permanent stimulation. Permanent pacing in the HB area enables Selective HB pacing (SHBP) or para-Hisian pacing (PHP) to be achieved. The aim of our study was to draw up a set of easy criteria to differentiate and validate the two kinds of stimulations according to the pacing output and the ECG/EKG signals. METHODS AND RESULTS: From February to July 2005, 17 patients eligible for a pacemaker (PM) procedure underwent implantation with the Medtronic SelectSecure lead (Medtronic, Minneapolis, MN, USA) screwed into the HB area.SHBP was defined when the intrinsic QRS was equal, in both duration and morphology, to the paced QRS, the His-Ventricular (H-V) interval was equal to Pace-Ventricular interval (Vp-V) and, at low output, only the HB was captured, while increasing the output resulted in both the HB and right ventricular (RV) being captured (widening of QRS at high output). Conversely, PHP was defined when the intrinsic QRS differed from the paced one, either in morphology or in duration and, at high output, both the RV and HB were captured (non-SHBP), while decreasing the output resulted in losing HB capture (widening of QRS at low output). According to these criteria, SHBP was achieved in 11 patients, while in the remaining 6, PHP was obtained. No adverse events were reported. CONCLUSIONS: The above criteria enabled SHBP and PHP to be validated easily and clearly. A longer follow-up will be needed in order to ascertain whether the clinical outcome of these two approaches differs.


Asunto(s)
Arritmias Cardíacas/prevención & control , Fascículo Atrioventricular , Estimulación Cardíaca Artificial/métodos , Electrocardiografía/métodos , Selección de Paciente , Anciano , Electrocardiografía/instrumentación , Femenino , Humanos , Masculino , Marcapaso Artificial , Resultado del Tratamiento
3.
Dig Liver Dis ; 33 Suppl 2: S12-20, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11827357

RESUMEN

Prostaglandins play important roles in the pathophysiological mechanism of action of platelets and endothelial cells in the cardiovascular system. The two isoforms of cyclo-oxygenase, respectively cyclo-oxygenase-1 and cyclo-oxygenase-2, are differently expressed in these cells. Activated platelets show a relatively large amount of cyclo-oxygenase-1, whereas endothelial cells have the gene for cyclo-oxygenase-2, the expression of which follows cell activation. In the atherosclerosis lesion, prostaglandin synthesis is mainly mediated by the inducible cyclo-oxygenase-2 expressed in macrophages/foam cells, smooth muscle cells and endothelial cells. Aspirin, a selective platelet cyclo-oxygenase-1 inhibitor still remains the most extensively studied antiplatelet agent, even though there is growing evidence that many other compounds could be valuable either in association, or alternatives in antithrombotic therapy.


Asunto(s)
Enfermedad de la Arteria Coronaria/enzimología , Isoenzimas/farmacología , Prostaglandina-Endoperóxido Sintasas/metabolismo , Prostaglandina-Endoperóxido Sintasas/farmacología , Aspirina/farmacología , Moléculas de Adhesión Celular/efectos de los fármacos , Enfermedad de la Arteria Coronaria/metabolismo , Ciclooxigenasa 1 , Ciclooxigenasa 2 , Inhibidores de la Ciclooxigenasa 2 , Inhibidores de la Ciclooxigenasa/farmacología , Eicosanoides/metabolismo , Humanos , Proteínas de la Membrana , Activación Plaquetaria/efectos de los fármacos
4.
J Cardiovasc Electrophysiol ; 11(9): 1043-7, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11021475

RESUMEN

We describe the unique case of a heart transplant patient with type I atrial fibrillation that arose in the donor atrium during a late acute rejection episode and conducted to the recipient atrium with second-degree type I local block. After internal cardioversion, programmed stimulation showed bidirectional decremental conduction across the suture line with nearly equal atrioatrial interval, whereas the recipient atrium showed progressively delayed intra-atrial conduction. These findings strongly suggest that the mechanism of atrioatrial conduction may be electrical propagation along viable myocardium bridging the surgical scar and that the electrophysiologic characteristics of the recipient atrium are involved in decremental conduction across the suture line.


Asunto(s)
Fibrilación Atrial/etiología , Fibrilación Atrial/fisiopatología , Sistema de Conducción Cardíaco/fisiopatología , Trasplante de Corazón , Electrocardiografía , Humanos , Masculino , Persona de Mediana Edad , Donantes de Tejidos
5.
J Reprod Med ; 45(5): 403-9, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10845174

RESUMEN

OBJECTIVE: To determine the iron bioavailability in two popular prenatal multivitamin/multimineral supplement tablets containing 27 mg elemental iron. STUDY DESIGN: Iron absorption during an eight-hour period following ingestion of a multivitamin/multimineral formulation, both fasting and with a standardized meal, was measured in a group of 30 pregnant women (24-32 weeks of gestation) and statistically compared. The prenatal formulations were Stuartnatal Plus and Materna (Wyeth-Ayerst Pharmaceuticals, Philadelphia, Pennsylvania), and each contains 27 mg of elemental iron. A placebo was included in the study for the control group in this crossover, single-blind study. RESULTS: The net iron bioavailability (mean +/- SE) of Stuartnatal Plus and Materna, accounting for diurnal variation, and the iron ingested with the standardized meal was 5.4 +/- 0.4 and 4.6 +/- 0.2 mg, respectively, while fasting and 2.9 +/- 0.4 and 2.7 +/- 0.4 mg, respectively, postprandially. The total amount of iron absorption in the fasting states from both prenatal formulations exceeded the 3 mg of supplemental iron absorption per day recommended by the National Academy of Sciences. CONCLUSION: The results of this study indicate that these two prenatal multivitamin/multimineral formulations provide > 3.0 mg of supplemental iron absorption (fasting) as recommended by the National Academy of Sciences and 2.7 mg of iron absorption above the levels achieved following ingestion of a standard, low-iron test meal.


Asunto(s)
Suplementos Dietéticos , Hierro/farmacocinética , Embarazo/metabolismo , Adulto , Disponibilidad Biológica , Estudios Cruzados , Femenino , Humanos , Hierro/sangre , Política Nutricional , Valores de Referencia , Método Simple Ciego
6.
Int J Cardiol ; 68 Suppl 1: S63-71, 1999 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-10328613

RESUMEN

Unstable angina and non-Q-wave myocardial infarction still represent an unsolved problem for clinicians, owing to their unpredictable evolution and high incidence of coronary events in the follow-up. Traditional antithrombotic agents, unfractionated heparin and aspirin, have been proved to be highly effective, but show some important limitations. New potent antithrombotic therapy have been studied to improve their efficacy, with encouraging results. Among these drugs, low molecular weight heparins (for subcutaneous administration) and inhibitors of platelet glycoprotein receptor IIb/IIIa (for intravenous, and possibly oral, administration) are the most promising and are now under extensive investigation.


Asunto(s)
Angina Inestable/tratamiento farmacológico , Fibrinolíticos/uso terapéutico , Infarto del Miocardio/tratamiento farmacológico , Abciximab , Anticuerpos Monoclonales/uso terapéutico , Anticoagulantes/uso terapéutico , Aspirina/uso terapéutico , Heparina/uso terapéutico , Heparina de Bajo-Peso-Molecular/uso terapéutico , Humanos , Fragmentos Fab de Inmunoglobulinas/uso terapéutico , Inhibidores de Agregación Plaquetaria/uso terapéutico , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/antagonistas & inhibidores , Resultado del Tratamiento
7.
Circulation ; 96(9): 3006-12, 1997 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-9386169

RESUMEN

BACKGROUND: The duration of the QT interval is only a gross estimate of repolarization. Besides its limited accuracy and reproducibility, it does not provide information on the morphology of the T wave; thus, morphologic alterations such as notches can be only qualitatively described but not objectively quantified. METHODS AND RESULTS: To measure the complexity of repolarization in the long-QT syndrome (LQTS) patients, we previously applied principal component analysis to body surface mapping and found it useful in distinguishing normal from abnormal repolarization patterns (sensitivity, 87%). In the present study, we applied principal component analysis to 12-lead Holter recordings. The index of complexity of repolarization that we have developed (CR24h) reflects the average 24-hour complexity of repolarization and is mathematically defined as the average ratio between the second and the first eigenvalue. We studied 36 LQTS patients and 40 control subjects. A mean of 22+/-1.3 ECG recordings at 1-hour intervals was used in each patient, and a total of 1655 recordings were analyzed. CR24h was significantly higher in LQTS than in control subjects (34+/-12% versus 13+/-3%; P<.0001). A CR24h exceeding 2 SD above the mean of the control group (>20%) was present in 32 of 36 patients (88%). The negative predictive value of CR24h in LQTS was 88%, and the combination of prolonged QT and abnormal CR24h identified all LQTS patients from normal subjects, including 4 affected symptomatic individuals with a normal QT interval duration, suggesting that CR24h provides information independent of QT duration. CONCLUSIONS: Our data suggest that principal component analysis applied to 24-hour, 12-lead Holter recording adequately quantifies the complexity of ventricular repolarization and may become a useful noninvasive diagnostic tool in LQTS.


Asunto(s)
Electrocardiografía , Síndrome de QT Prolongado/fisiopatología , Adolescente , Adulto , Niño , Femenino , Humanos , Masculino
8.
Pacing Clin Electrophysiol ; 20(8 Pt 2): 2052-7, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9272507

RESUMEN

The long QT syndrome (LQTS) is a familial disease characterized by prolonged ventricular repolarization and high incidence of malignant ventricular tachyarrhythmias often occurring in conditions of adrenergic activation. Recently, the genes for the LQTS inked to chromosomes 3 (LQT3), 7 (LQT2), and 11 (LQT1) were identified as SCN5A, the cardiac sodium channel gene and as HERG and KvLQT1 potassium channel genes. These discoveries have paved the way for the development of gene-specific therapy for these three forms of LQTS. In order to test specific interventions potentially beneficial in the molecular variants of LQTS, we developed a cellular model to mimic the electrophysiological abnormalities of LQT3 and LQT2. Isolated guinea pig ventricular myocytes were exposed to anthopleurin and dofetilide in order to mimic LQT3 and LQT2, respectively. This model has been used to study the effect of sodium channel blockade and of rapid pacing showing a pronounced action potential shortening in response to Na+ channel blockade with mexiletine and during rapid pacing only in anthopleurin-treated cells but not in dofetilide-treated cells. Based on these results we tested the hypothesis that QT interval would shorten more in LQT3 patients in response to mexiletine and to increases in heart rate. Mexiletine shortened significantly the QT interval among LQT3 patients but not among LQT2 patients. LQT3 patients shortened their QT interval in response to increases in heart rate much more than LQT2 patients and healthy controls. These findings suggest that LQT3 patients are more likely to benefit from Na+ channel blockers and from cardiac pacing because they are at higher arrhythmic risk at slow heart rates. Conversely, LQT2 patients are at higher risk to develop syncope under stressful conditions, because of the combined arrhythmogenic effect of catecholamines with the insufficient adaptation of their QT interval. Along the same line of development of gene-specific therapy, recent data demonstrated that an increase in the extracellular concentration of potassium shortens the QT interval in LQT2 patients suggesting that intervention aimed at increasing potassium plasma levels may represent a specific treatment for LQT2. The molecular findings on LQTS suggest the possibility of developing therapeutic interventions targeted to specific genetic defects. Until definitive data become available, antiadrenergic therapy remains the mainstay in the management of LQTS patients, however it may be soon worth considering the addition of a Na+ channel blocker such as mexiletine for LQT3 patients and of interventions such as K+ channel openers or increases in the extracellular concentration of potassium for LQT1 and LQT2 patients.


Asunto(s)
Síndrome de QT Prolongado/genética , Potenciales de Acción/efectos de los fármacos , Antagonistas Adrenérgicos/uso terapéutico , Animales , Antiarrítmicos/farmacología , Estimulación Cardíaca Artificial , Cardiotónicos/farmacología , Cromosomas Humanos Par 11/genética , Cromosomas Humanos Par 3/genética , Cromosomas Humanos Par 7/genética , Modelos Animales de Enfermedad , Electrocardiografía/efectos de los fármacos , Terapia Genética , Cobayas , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Péptidos y Proteínas de Señalización Intercelular , Síndrome de QT Prolongado/tratamiento farmacológico , Síndrome de QT Prolongado/fisiopatología , Síndrome de QT Prolongado/terapia , Mexiletine/farmacología , Biología Molecular , Miocardio/citología , Péptidos/farmacología , Fenetilaminas/farmacología , Potasio/sangre , Potasio/uso terapéutico , Bloqueadores de los Canales de Potasio , Canales de Potasio/genética , Receptores Adrenérgicos/fisiología , Factores de Riesgo , Bloqueadores de los Canales de Sodio , Canales de Sodio/genética , Sulfonamidas/farmacología , Síncope/etiología , Taquicardia Ventricular/tratamiento farmacológico , Taquicardia Ventricular/fisiopatología , Taquicardia Ventricular/terapia
9.
Schweiz Med Wochenschr ; 126(41): 1727-31, 1996 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-8893413

RESUMEN

The idiopathic long QT syndrome is a congenital disease characterized by prolongation of the QT interval and by stress-induced syncopal episodes caused by the development of "torsades de pointes". Over the last decade, the great advances in the field of molecular biology have made it possible to elucidate the genetic causes of the disease. In particular, three genes have been implicated in the pathogenesis of the disease: SCN5A (LQT3), encoding for the cardiac sodium channel and located on chromosome 3, HERG (LQT2), encoding for a cardiac potassium channel (Ikr) and located on chromosome 7 and KVLQT1 (LQT1), located on chromosome 11 and encoding for a cardiac potassium channel whose electrophysiologic profile is still undefined. Within each of these genes several different mutations have been identified and subsequently expressed to determine the electrophysiological changes induced by the mutation in the normal function of the channels. These studies have suggested that LQT3 is caused by alterations in the inactivation of cardiac sodium channels while LQT2 is caused by a reduction in the delayed rectifier potassium current. Based on this evidence, we developed the first cellular model for LQTS in order to provide a mean of assessing the effect of different interventions in two different forms of disease, LQT2 and LQT3. We exposed guinea pig ventricular myocytes to anthopleurin, a toxin that interferes with the inactivation of INa, and to dofetilide, a selective blocker of Ikr, obtaining a prolongation of cellular repolarization with both drugs. We then exposed cells to a Na+ channel blocker, mexiletine, which significantly reduced APD in cells treated with anthopleurin while it did not modify the prolongation induced by dofetilide. In addition, anthopleurin-treated cells demonstrated a greater shortening of APD to rapid pacing than both control and dofetilide-treated cells. Based on this experimental evidence, we tested the same therapeutic interventions, mexiletine and pacing, in fifteen genetically characterized LQTS patients. Mexiletine significantly shortened the QT interval in LQT3 patients but not in LQT2 patients. When we examined the response to an increase in heart rate, we found that LQT3 patients had a more shortened QT interval in response to heart rate changes than LQT2 patients and than healthy controls.


Asunto(s)
Proteínas de Transporte de Catión , Proteínas de Unión al ADN , Síndrome de QT Prolongado/genética , Canales de Potasio con Entrada de Voltaje , Transactivadores , Animales , Antiarrítmicos/farmacología , Cardiotónicos/farmacología , Canal de Potasio ERG1 , Canales de Potasio Éter-A-Go-Go , Cobayas , Ventrículos Cardíacos/citología , Ventrículos Cardíacos/efectos de los fármacos , Humanos , Técnicas In Vitro , Péptidos y Proteínas de Señalización Intercelular , Síndrome de QT Prolongado/terapia , Mexiletine/farmacología , Péptidos/farmacología , Fenetilaminas/farmacología , Mutación Puntual , Canales de Potasio/efectos de los fármacos , Canales de Potasio/genética , Canales de Potasio/fisiología , Anémonas de Mar , Canales de Sodio/efectos de los fármacos , Canales de Sodio/genética , Sulfonamidas/farmacología , Regulador Transcripcional ERG
10.
Circ Res ; 78(6): 1009-15, 1996 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8635231

RESUMEN

The long-QT syndrome (LQTS) is a hereditary disorder characterized by an abnormally prolonged QT interval and by life-threatening arrhythmias. Recently, two of the genes responsible for LQTS have been identified: SCN5A, a voltage-dependent Na+ channel on chromosome 3 (LQT3), and HERG, responsible for the rapid component of the delayed rectifier current (IKr), on chromosome 7 (LQT2). We developed an in vitro model to attempt reproduction of the expected alterations in LQT3 and LQT2 patients. Guinea pig ventricular myocytes were exposed to anthopleura toxin A (anthopleurin), an inhibitor of the inactivation of the Na+ current, and to dofetilide, a selective blocker of IKr. Both interventions significantly prolonged action potential duration (APD), by 54 +/- 13 and 62 +/- 16 ms, respectively. Cells pretreated with anthopleurin significantly shortened APD in response to mexiletine, isoproterenol, and rapid pacing (from 264 +/- 38 to 226 +/- 32 ms after mexiletine, P < .001). On the contrary, cells exposed to dofetilide did not shorten the APD after mexiletine and even prolonged it after initial exposure to isoproterenol (from 280 +/- 25 to 313 +/- 20 ms, P < .001); during rapid pacing, APD was shortened but less (38 +/- 9 versus 60 +/- 11 ms, P < .05) than in anthopleurin-treated cells. This study shows that a cellular model for LQTS, based on the recent advances in molecular genetics, can provide adequate "phenotypes" of prolonged repolarization amenable to the testing of interventions of potential clinical relevance. We found differential responses to Na+ channel blockade, to beta-adrenergic stimulation, and to rapid pacing according to specific pretreatment with either anthopleurin (to mimic LQT3) or dofetilide (to mimic LQT2). These different responses in myocytes bear striking similarities with the differential response to analogous interventions in LQTS patients with mutations on the SCN5A and HERG genes.


Asunto(s)
Proteínas de Transporte de Catión , Síndrome de QT Prolongado/genética , Canales de Potasio con Entrada de Voltaje , Canales de Potasio/genética , Receptores Adrenérgicos beta/fisiología , Bloqueadores de los Canales de Sodio , Canales de Sodio/genética , Potenciales de Acción , Animales , Estimulación Cardíaca Artificial , Canales de Potasio Éter-A-Go-Go , Cobayas , Péptidos y Proteínas de Señalización Intercelular , Isoproterenol/farmacología , Mexiletine/farmacología , Mutación , Péptidos/farmacología , Fenetilaminas/farmacología , Sulfonamidas/farmacología
11.
Circulation ; 92(12): 3381-6, 1995 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-8521555

RESUMEN

BACKGROUND: The genes for the long QT syndrome (LQTS) linked to chromosomes 3 (LQT3) and 7 (LQT2) were identified as SCN5A, the cardiac Na+ channel gene, and as HERG, a K+ channel gene. These findings opened the possibility of attempting gene-specific control of ventricular repolarization. We tested the hypothesis that the QT interval would shorten more in LQT3 than in LQT2 patients in response to mexiletine and also in response to increases in heart rate. METHODS AND RESULTS: Fifteen LQTS patients were studied. Six LQT3 and 7 LQT2 patients were treated with mexiletine, and its effects on QT and QTc were measured. Mexiletine significantly shortened the QT interval among LQT3 patients (QTc from 535 +/- 32 to 445 +/- 31 ms, P < .005) but not among LQT2 patients (QTc from 530 +/- 79 to 503 +/- 60 ms, P = NS). LQT3 patients (n = 7) shortened their QT interval in response to increases in heart rate much more than LQT2 patients (n = 4) and also more than 18 healthy control subjects (9.45 +/- 3.3 versus 3.95 +/- 1.97 and 2.83 +/- 1.33, P < .05; data expressed as percent reduction in QT per 100-ms shortening in RR). Among these patients, there is also a trend for LQT2 patients to have syncope or cardiac arrest under emotional or physical stress and for LQT3 patients to have cardiac events either at rest or during sleep. CONCLUSIONS: This is the first study to demonstrate differential responses of LQTS patients to interventions targeted to their specific genetic defect. These findings also suggest that LQT3 patients may be more likely to benefit from Na+ channel blockers and from cardiac pacing because they would be at higher risk of arrhythmia at slow heart rates. Conversely, LQT2 patients may be at higher risk to develop syncope under stressful conditions because of the combined arrhythmogenic effect of catecholamines with the insufficient adaptation of their QT interval when heart rate increases.


Asunto(s)
Antiarrítmicos/farmacología , Cromosomas Humanos Par 3 , Cromosomas Humanos Par 7 , Frecuencia Cardíaca/fisiología , Síndrome de QT Prolongado/genética , Síndrome de QT Prolongado/fisiopatología , Mexiletine/farmacología , Mutación , Canales de Potasio/genética , Canales de Sodio/genética , Adulto , Estimulación Cardíaca Artificial , Estudios de Casos y Controles , Mapeo Cromosómico , Femenino , Humanos , Síndrome de QT Prolongado/terapia , Masculino , Bloqueadores de los Canales de Sodio
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