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1.
Heart Lung Circ ; 28(8): 1190-1196, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30262155

RESUMEN

BACKGROUND: Pulmonary arterial hypertension (PAH) occurs in 35% to 65% of hyperthyroid patients. Despite this high frequency, only a few authors have examined the effects of hyperthyroidism treatment on PAH and the right ventricle. We evaluated the effects of hyperthyroidism and its reversal on cardiovascular structure and function using Doppler echocardiography. METHODS: We prospectively evaluated 32 patients (42.5±11.9years old) with thyrotoxicosis. Exclusion criteria included previous cardiovascular disease. An echocardiogram was performed at the time of hyperthyroidism diagnosis and after normalisation of free thyroxine (T4) levels. Patients were divided into two groups according to the presence or absence of PAH at the diagnosis, or at two moments, before and after T4 normalisation. RESULTS: Graves' disease was the most frequent aetiology (75%) of hyperthyroidism. Pulmonary arterial hypertension was observed in 43.8% of patients. Free T4 concentration was higher in PAH than non-PAH patients. Free T4 normalised after 5 (2.0-10.5; median and percentiles) months of treatment. Cardiac chamber sizes and cardiac output were higher in PAH. Right ventricular (RV) systolic function was impaired in PAH. Cardiac output and free T4 (r=0.42; p<0.05) correlated with pulmonary artery systolic pressure (PASP). Cardiac chamber size, cardiac output, left ventricular ejection fraction, and PASP (34.0±8.6 to 21.7±4.5mmHg) reduced after treatment. Right ventricular myocardial performance index and fractional area change improved after T4 normalisation. CONCLUSIONS: Pulmonary arterial hypertension is highly prevalent in hyperthyroid patients and is combined with increased cardiac chambers size and cardiac output, and impaired RV function. Cardiovascular changes are reversible after T4 normalisation in patients without cardiovascular disease.


Asunto(s)
Presión Arterial , Hipertensión Pulmonar Primaria Familiar , Ventrículos Cardíacos , Hipertiroidismo , Disfunción Ventricular Derecha , Función Ventricular Derecha , Adulto , Hipertensión Pulmonar Primaria Familiar/sangre , Hipertensión Pulmonar Primaria Familiar/diagnóstico por imagen , Hipertensión Pulmonar Primaria Familiar/fisiopatología , Femenino , Ventrículos Cardíacos/diagnóstico por imagen , Ventrículos Cardíacos/fisiopatología , Humanos , Hipertiroidismo/sangre , Hipertiroidismo/diagnóstico por imagen , Hipertiroidismo/fisiopatología , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Disfunción Ventricular Derecha/diagnóstico por imagen , Disfunción Ventricular Derecha/fisiopatología
2.
Oper Dent ; 45(5): E255-E270, 2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-33170938

RESUMEN

CLINICAL RELEVANCE: Non-carious cervical lesion restorations using a dual-cure universal adhesive in self-etch and etch-and-rinse mode showed satisfactory clinical performance after 18 months. SUMMARY: Objectives: The objective of this multicenter, double-blind, split-mouth randomized clinical trial was to evaluate the clinical performance of a new dual-cure universal adhesive system (Futurabond U, Voco GmBH) when applied using different strategies over a period of 18 months.Methods and Materials: Fifty patients participated in this study. Two hundred non-carious cervical lesions were restored using the adhesive Futurabond U according to four adhesive strategies (n=50 per group): only self-etch (SEE), selective enamel etching + self-etch (SET), etch-and-rinse with dry dentin (ERDry), and etch-and-rinse with wet dentin (ERWet). After the adhesive application, cavities were restored using Admira Fusion composite resin. These restorations were evaluated according to FDI World Dental Federation criteria for the following characteristics: retention/fracture, marginal adaptation, marginal staining, postoperative sensitivity, and caries recurrence.Results: After 18 months, only four patients (12 months: one patient, n=4 restorations; and 18 months: three patients, n=12 restorations) were not evaluated. Fourteen restorations were lost after 18 months of clinical evaluation (four for SEE, three for SET, three for ERDry, and four for ERWet). The retention rates for 18 months (95% confidence interval) were 92% (81%-97%) for SEE, 94% (83%-97%) for SET, 94% (83%-97%) for ERDry, and 92% (81%-97%) for ERWet (p>0.05). Thirty-eight restorations were considered to have minor discrepancies in marginal adaptation at the 18-month recall (13 for SEE, 13 for SET, six for ERDry, and six for ERWet; p>0.05). Fourteen restorations were detected as a minor marginal discoloration at the 18-month recall (six for SEE, six for SET, one for ERDry, and one for ERWet; p>0.05). However, all were considered clinically acceptable. No restorations showed postoperative sensitivity or caries recurrence at the time.Conclusion: The clinical performance of the Futurabond U did not depend on the bonding strategy used, and it was considered reliable after 18 months of clinical evaluation, although more marginal discrepancy was observed in the self-etch group.


Asunto(s)
Recubrimiento Dental Adhesivo , Caries Dental , Resinas Compuestas , Caries Dental/terapia , Cementos Dentales , Adaptación Marginal Dental , Restauración Dental Permanente , Recubrimientos Dentinarios , Humanos , Cementos de Resina , Cuello del Diente
3.
Oper Dent ; 45(5): 547-555, 2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32352351

RESUMEN

CLINICAL RELEVANCE: The photo-initiator system based on an advanced polymerization system may be an alternative that can be used to overcome the disadvantages of radicular dentin, especially for the apical third. SUMMARY: Objectives: The purpose of this study was to evaluate the effects of universal adhesives with different photo-initiator systems applied in etch-and-rinse (ER) and self-etch (SE) modes on dentin interaction (push-out bond strength [PBS], nanoleakage [NL], and degree of conversion [DC] within the hybrid layer) in the different root thirds after fiber post cementation.Methods and Materials: Roots of endodontically prepared human premolars were randomly divided into six groups according to one of three adhesive systems (Scotchbond Universal [SBU], Ambar Universal [AMB], and Ambar Universal APS [AMB-APS]) and two adhesive strategies (ER and SE) for each system. Posts were cemented, and PBS was tested at 0.5 mm/min. The NL was evaluated by scanning electron microscopy. DC was measured using micro-Raman spectroscopy. The data were analyzed by three-way analysis of variance and Tukey tests (α=0.05).Results: AMB-APS showed similar performance in all root thirds (p>0.05) and higher values of DC, especially in the apical third (p<0.0001). AMB and SBU showed the lowest values in the apical third (p<0.0001).Conclusions: The APS photo-initiator system contained in universal adhesives is a feasible alternative for improving radicular bonding procedure.


Asunto(s)
Recubrimiento Dental Adhesivo , Recubrimientos Dentinarios , Adhesivos , Bisfenol A Glicidil Metacrilato , Cementos Dentales , Dentina , Humanos , Ensayo de Materiales , Cementos de Resina , Resistencia a la Tracción
4.
Cochrane Database Syst Rev ; (3): CD006115, 2006 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-16856115

RESUMEN

BACKGROUND: Azapirones are a group of drugs that work at the 5-HT1A receptor and are used to treat patients suffering from generalized anxiety disorder (GAD). However, several studies have shown conflicting results. Whether azapirones are useful as first line treatment in general anxiety disorders still needs to be answered. OBJECTIVES: To assess the efficacy and the acceptability of azapirones for the treatment of GAD. SEARCH STRATEGY: Initially the Cochrane Collaboration Depression, Anxiety and Neurosis Controlled Trials Register (CCDANCTR) and The Cochrane Central Register of Controlled Trials (CENTRAL) were searched, incorporating results of group searches of MEDLINE (1966 to June 2005), EMBASE (1980 to June 2005), CINAHL (1982 to June 2005), PsycLIT (1974 to June 2005), PSYNDEX (1977 to June 2005), and LILACS (1982 to June 2005). Subsequently the revised Cochrane Collaboration Depression, Anxiety and Neurosis Controlled Trials Registers (CCDANCTR-Studies and CCDANCTR-References) were searched on 21-10-2005. Reference lists of relevant papers and major text books of anxiety disorder were examined. Authors, other experts in the field and pharmaceutical companies were contacted for knowledge of suitable trials, published or unpublished. Specialist journals concerning azapirones were handsearched. SELECTION CRITERIA: Randomized controlled trials of azapirones, including buspirone versus placebo and/or other medication and/or psychological treatment, were included. Participants were males and females of all ages with a diagnosis of generalized anxiety disorder. DATA COLLECTION AND ANALYSIS: Data were extracted from the original reports independently by CC, MA and MT. The main outcomes studied were related to the objectives stated above. Data were analysed for generalized anxiety disorder versus placebo, versus other medication and versus psychological treatment separately. Data were analysed using Review Manager Version 4.2.7. MAIN RESULTS: Thirty six trials were included in the review, reporting on 5908 participants randomly allocated to azapirones and/or placebo, benzodiazepines, antidepressants, psychotherapy or kava kava. Azapirones, including buspirone, were superior to placebo in treating GAD. The calculated number needed to treat for azapirones using the Clinical Global Impression scale was 4.4 (95% confidence interval (CI) 2.16 to 15.4). Azapirones may be less effective than benzodiazepines and we were unable to conclude if azapirones were superior to antidepressants, kava kava or psychotherapy. Azapirones appeared to be well tolerated. Fewer participants stopped taking benzodiazepines compared to azapirones. The length of studies ranged from four to nine weeks, with one study lasting 14 weeks. AUTHORS' CONCLUSIONS: Azapirones appeared to be useful in the treatment of GAD, particularly for those participants who had not been on a benzodiazepine. Azapirones may not be superior to benzodiazepines and do not appear as acceptable as benzodiazepines. Side effects appeared mild and non serious in the azapirone treated group. Longer term studies are needed to show that azapirones are effective in treating GAD, which is a chronic long-term illness.


Asunto(s)
Ansiolíticos/uso terapéutico , Trastornos de Ansiedad/tratamiento farmacológico , Ansiolíticos/efectos adversos , Antidepresivos/uso terapéutico , Trastornos de Ansiedad/terapia , Benzodiazepinas/uso terapéutico , Buspirona/uso terapéutico , Humanos , Psicoterapia , Pirimidinas/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto
5.
J Am Coll Cardiol ; 14(1): 242-5, 1989 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2738266

RESUMEN

Monophasic and single capacitor and dual capacitor biphasic truncated exponential shocks were tested in pentobarbital-anesthetized dogs with use of a nonthoracotomy internal defibrillation pathway consisting of a right ventricular catheter electrode and a subcutaneous chest wall patch electrode. Seven dogs weighing 20.2 +/- 0.5 kg were utilized. Monophasic pulses of 10 ms duration were compared with three biphasic pulses. All biphasic waveforms had an initial positive phase (P1) followed by a terminal negative phase (P2) and the total duration of P1 plus P2 was 10 ms. The dual capacitor biphasic waveform (P1 9 ms, P2 1 ms) had equal initial voltages of P1 and P2. Two simulated single capacitor biphasic waveforms were also tested, the first designed to minimize the magnitude of P2 (P1 9 ms, P2 1 ms with initial voltage of P2 equal to 0.3 of the initial voltage of P1) and the second to maximize P2 (P1 5 ms, P2 5 ms with initial voltage of P2 = 0.5 P1). Alternating current was used to induce ventricular fibrillation and four trials of eight initial voltages from 100 to 800 V were performed for each of the four waveforms. Stepwise logistic regression was utilized to construct curves relating probability of successful defibrillation and energy. In the logistic model, the dual capacitor biphasic and single capacitor biphasic waveforms that maximized P2 were associated with significantly (p less than 0.001) lower energy requirements for defibrillation than those of the monophasic waveform. The single capacitor biphasic waveform that minimized P2 was not significantly better than the monophasic waveform.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Cardioversión Eléctrica/métodos , Animales , Perros , Conductividad Eléctrica
6.
J Am Coll Cardiol ; 12(3): 739-45, 1988 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-3403834

RESUMEN

Pentobarbital-anesthetized dogs were studied to determine the relative efficacy of monophasic and biphasic truncated exponential shocks employing a nonthoracotomy internal defibrillation pathway that consisted of a right ventricular catheter electrode (cathode) and a subcutaneous chest wall patch electrode (anode). In part 1 of the experiments, six dogs (19.6 +/- 1.1 kg) were utilized. Monophasic pulses of 5, 7.5, 10 and 12.5 ms duration were compared with biphasic pulses of the same total duration. The biphasic pulses had an initial positive phase (P1) followed by a terminal negative phase (P2) with the initial voltage equal for each phase. For each biphasic total pulse width, five relative P1 versus P2 durations were tested (50 and 50%, 75 and 25%, 90 and 10%, 25 and 75%, 10 and 90%). Ventricular fibrillation was induced by alternating current and pulse configurations were tested randomly to determine the minimal voltage and energy for defibrillation (threshold). Biphasic shocks with P1 longer than P2 were associated with significantly lower (p less than 0.01) energy thresholds than were monophasic shocks. Additionally, there was no significant relation between pulse width and voltage or energy thresholds. In part 2 of the experiments, six dogs (20.2 +/- 1.6 kg) were studied. Monophasic shocks were compared with biphasic shocks with P1 versus P2 durations of 75 and 25% and 90 and 10% for total pulse widths of 7.5, 10 and 12.5 ms. Threshold determinations were performed as in part 1. Subsequently, five initial voltages clustered about threshold were randomly tested four times and dose-response curves constructed for each pulse configuration with the use of stepwise logistic regression. Biphasic shocks resulted in significantly lower energy (p less than 0.0001) and voltage (p less than 0.001) requirements than did monophasic shocks.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Cardioversión Eléctrica/métodos , Corazón/fisiología , Animales , Perros , Conductividad Eléctrica , Sistema de Conducción Cardíaco/fisiología , Probabilidad , Factores de Tiempo
7.
Am J Cardiol ; 82(9): 1052-5, 1998 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-9817480

RESUMEN

With use of transesophageal echocardiography, the short-term effects of transthoracic electrical cardioversion of atrial flutter (AFI) on atrial mechanical function and spontaneous echo contrast were determined. Thirty patients who had AFI for a mean of 6.4 +/- 12.2 months underwent transthoracic cardioversion. A transesophageal echocardiogram was recorded immediately before cardioversion, and left atrial appendage emptying velocity and spontaneous contrast were assessed serially at 1, 3, and 5 minutes after cardioversion in 28 patients, and also at 8, 10, and 15 minutes after cardioversion in a subgroup of 13 patients. Cardioversion was deferred in 2 patients (7%) because a thrombus was found in the left atrial appendage. Before cardioversion, spontaneous contrast was present in the left atrium in 7 of 28 patients (25%) who underwent cardioversion. The mean left atrial appendage emptying velocity of 54 +/- 22 cm/s before cardioversion fell by 26% to 40 +/- 25 cm/s at 1 minute after restoration of sinus rhythm (p <0.01). There were no significant changes in the mean left atrial appendage-emptying velocity between 1 and 15 minutes after cardioversion. Within 5 minutes after conversion to sinus rhythm, left atrial spontaneous echo contrast developed de novo or worsened in 12 of the 28 patients (43%). In conclusion, the results of this study demonstrate that persistent AFI may be associated with left atrial thrombi before cardioversion and that cardioversion of AFI is associated with a significant degree of atrial stunning and formation of spontaneous echo contrast.


Asunto(s)
Aleteo Atrial/diagnóstico por imagen , Aleteo Atrial/fisiopatología , Aleteo Atrial/terapia , Función del Atrio Izquierdo , Ecocardiografía Transesofágica , Cardioversión Eléctrica , Adulto , Anciano , Enfermedad Crónica , Trombosis Coronaria/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
8.
Chest ; 103(2): 616-7, 1993 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8432165

RESUMEN

A 59-year-old woman who underwent laparoscopic cholecystectomy for symptomatic cholecystitis presented four months later with fever, malaise, anorexia, hemoptysis and lithoptysis. Chemical analysis of the expectorated lithes revealed them to be gallstones. Ultrasound studies of the right upper quadrant demonstrated both supradiaphragmatic and subdiaphragmatic fluid collections containing echogenic fragments. ERCP failed to demonstrate retained ductal stones or fistula formation. To our knowledge, this is the first reported case of cholelithoptysis and demonstrates an unusual complication of gallstone retention following laparoscopic cholecystectomy.


Asunto(s)
Colecistectomía Laparoscópica/efectos adversos , Colelitiasis , Bronquios , Femenino , Humanos , Persona de Mediana Edad
9.
Can J Cardiol ; 12(4): 407-11, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8608460

RESUMEN

BACKGROUND: Defibrillation waveform and its spatial and temporal distribution are important determinants of its efficacy. Previous comparisons of monophasic, biphasic and sequential waveforms have used one current pathway for monophasic and biphasic defibrillation and two pathways for sequential defibrillation thus confounding a direct comparison of the waveforms. DESIGN: This study compared monophasic, biphasic and sequential pulse defibrillation over a single current pathway using a nonthoracotomy and a thoracotomy lead system in a dog model. MAIN RESULTS: Eight mongrel dogs (mean weight 21.6+/-2.9 kg) first underwent nonthoracotomy defibrillation testing followed by a median sternotomy and implantation of two 13.9 cm2 epicardial patch electrodes posterior = cathode). Nonthoracotomy electrode configuration consisted of a right ventricular catheter (cathode) and a chest wall subcutaneous patch (anode). After 10 s of alternating current induced ventricular fibrillation, defibrillation was attempted with a test shock. Monophasic, biphasic and sequential shocks of 10 ms total duration were compared. Biphasic and sequential shocks consisted of two 5 ms components separated by 0.25 ms switch time constant. Four trials of five leading edge voltages were performed for each waveform and stepwise logistic regression analysis was used to determine 80% probability of successful defibrillation (E80). For epicardial defibrillation, E80s were monophasic 11.3+/-1.5 J; biphasic 7.9+/-1.2 J; and sequential 12.1+/-1.4 J. For nonthoracotomy defibrillation, E80s were monophasic 17.7+/-3.4 J; biphasic 13.8+/-3.3 J; and sequential 18.2+/-3.5 J. The mean E80 for biphasic pulses was significantly lower than monophasic or sequential pulses for either lead system. CONCLUSIONS: Biphasic pulses are superior to monophasic or sequential pulses delivered over a single current pathway.


Asunto(s)
Desfibriladores Implantables , Cardioversión Eléctrica/instrumentación , Fibrilación Ventricular/fisiopatología , Animales , Modelos Animales de Enfermedad , Perros , Cardioversión Eléctrica/métodos , Electrodos Implantados , Fibrilación Ventricular/terapia
10.
Cad Saude Publica ; 15(4): 719-28, 1999.
Artículo en Portugués | MEDLINE | ID: mdl-10633194

RESUMEN

The aim of this paper was to evaluate the accuracy of data on death certificates for occupation and main cause of death. Measure of agreement was assessed comparing data from death certificates with those from both medical records and next-of-kin interviews, analyzing information for 552 residents of Botucatu, Southeast Brazil, who died in 1997. Kappa coefficients of 0.31 (95% C.I. 0. 29-0.34) and 0.76 (95% C.I. 0.75-0.76) were obtained for data on occupation and main cause of death, coded by a Brazilian two-digit classification and the three-digit ICD-10 classification, respectively. One can conclude that, although quality of the main cause of death is acceptable for pilot studies, data on occupation taken only from death certificates is not accurate enough to be used in epidemiological research.


Asunto(s)
Causas de Muerte , Certificado de Defunción , Ocupaciones , Brasil , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados
11.
Rev Saude Publica ; 33(6): 593-601, 1999 Dec.
Artículo en Portugués | MEDLINE | ID: mdl-10689376

RESUMEN

INTRODUCTION: The main causes of illness and death in Brazil have been migrating backwards into the younger population during the last few years, increasing especially in the more productive age groups. Given the relationship between work and health/disease process, the hypothesis to be considered is that this phenomenon is partially due to the deterioration of workplace conditions. To contribute to investigating this hypothesis, this study estimates mortality risk indicators for the population of Botucatu, in the Southeast region of Brazil, classified according to their occupation. METHODS: Standardized mortality coefficient, standardized risk ratio, and years of potential life lost were calculated for the inhabitants of Botucatu who died after their 10th birthday, between January 1997 and March 1998, and classified according to their occupation and main cause of death. Occupational and medical information was obtained by interviewing families of the deceased and their doctors, and checking medical files. RESULTS: The standardized mortality coefficient ranged from 0.6 to 39.9 deaths/1000 workers in different occupations. The years of potential life lost ranged form 33 to 334 years/1000 workers. The ranking of causes of death varied according to occupation and the mortality risk considered. CONCLUSION: The risk measures analyzed showed a high heterogeneity when associated to occupation and causes of death, which reflects the great social inequality existing in the studied population.


Asunto(s)
Indicadores de Salud , Mortalidad , Ocupaciones/estadística & datos numéricos , Adolescente , Adulto , Anciano , Brasil/epidemiología , Causas de Muerte , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mortalidad/tendencias , Ocupaciones/clasificación , Oportunidad Relativa , Prorrateo de Riesgo Financiero
12.
S Afr Med J ; 71(1): 28-31, 1987 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-3798289

RESUMEN

Two hundred unbooked mothers were questioned after delivery and their reasons for non-attendance at antenatal clinics were determined. The control group consisted of 310 mothers who had booked early and were good clinic attenders. The most significant difference between the two groups was that the unbooked mothers were of lower socioeconomic status and lived in poorer areas situated further from the hospital. The main reasons given for not attending hospital clinics included the expense involved and the fact that the mothers often stayed outside the area during the pregnancy.


Asunto(s)
Aceptación de la Atención de Salud , Atención Prenatal , Adolescente , Adulto , Factores de Edad , Instituciones de Atención Ambulatoria , Femenino , Humanos , Paridad , Embarazo , Atención Prenatal/economía , Factores Socioeconómicos , Sudáfrica
13.
S Afr Med J ; 71(1): 31-4, 1987 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-3798290

RESUMEN

The fetal outcome was compared in 200 unbooked pregnancies and in 310 pregnancies in which the mothers had booked before 22 weeks' gestation. Of the babies born to the unbooked mothers 36% weighed less than 2,500 g compared with only 12.5% in the booked group. Among the unbooked patients the neonatal mortality rate was three times higher than among booked cases. Maternal intrinsic factors, including parity and socio-economic status, made a major contribution to the incidence of low-birth-weight babies. The need for improved attendance at clinics and for education about antenatal care in the coloured population under review is well documented. The introduction of peripheral clinics and free antenatal care could play a major role in improving fetal outcome.


Asunto(s)
Aceptación de la Atención de Salud , Atención Prenatal , Adolescente , Adulto , Negro o Afroamericano , Instituciones de Atención Ambulatoria , Peso al Nacer , Población Negra , Parto Obstétrico , Femenino , Muerte Fetal/epidemiología , Humanos , Mortalidad Infantil , Embarazo , Sudáfrica
14.
Artículo en Inglés | MEDLINE | ID: mdl-2900108

RESUMEN

1. The locations of freshwater yellow eels in an eight-chambered octagonal behavior tank were videotaped during six-day intervals while the animals were being subjected to normal and experimental magnetic fields. 2. The earth's magnetic field (0.5 g) was utilized for two control periods at the start and completion of each run for each animal. 3. During each run, the sequence of applied magnetic fields was +1.0, 0.0, -0.5 and -1.0 g, each being applied for a period of 24 hr. 4. Under the influence of the earth's magnetic field, the eels showed a preference for a northeast direction (27.01%). During the second control period (i.e. after being subjected to variations in the magnetic field), the animals showed a dual preference for north and northwest directions (23.02% and 25.9%, respectively). 5. In a 0.0 g field, the eels preferred the north chamber (24.43%) and the vestibule of the behavior tank (19.46%); a preference for north was also obtained with a field of +1.0 g (25.95%). 6. The preferred direction with the -0.5 and -1.0 g fields was southeast (20.93 and 26.71%, respectively).


Asunto(s)
Anguilla/fisiología , Magnetismo , Orientación , Animales , Métodos
15.
J Cardiovasc Electrophysiol ; 8(8): 895-903, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9261716

RESUMEN

INTRODUCTION: A stimulus delivered in the T wave of a paced cardiac cycle can induce ventricular fibrillation (VF). If the stimulus strength is increased, the probability of inducing VF decreases. This study determines an ideal mathematical model (a dose-response curve) for the relationship between the shock strength and the probability of inducing VF or defibrillating. METHODS AND RESULTS: Defibrillating electrodes were implanted in the right ventricle and superior vena cava in 16 pigs. The electrode in the vena cava was electrically connected to a cutaneous patch. The same electrodes were used for both VF induction and defibrillation. T wave stimuli were given at the peak of the T wave according to a modified up-down protocol (40 V up, 20 V down). When a T wave stimulus induced VF, a defibrillation stimulus was delivered 10 seconds later, also according to the modified up-down protocol. Exponential, logistic, log-dose logistic, piecewise linear and Box-Tiao dose-response curves were fit to the resulting data using the maximum likelihood method. For the defibrillation data, it was found that only the logistic and Box-Tiao curves fit all of the animals (P < 0.05). For VF induction, only the Box-Tiao curve fit all of the animals (P < 0.05). Extrapolating along a dose-response curve that did not fit to a shock strength with a very low probability of inducing VF or a very high probability of defibrillating yielded errors as great as 610 V. CONCLUSION: The Box-Tiao dose-response curve is the best single choice for fitting VF induction or defibrillation datasets.


Asunto(s)
Cardioversión Eléctrica , Fibrilación Ventricular/terapia , Animales , Porcinos , Fibrilación Ventricular/fisiopatología
16.
Circulation ; 91(4): 1247-52, 1995 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-7850965

RESUMEN

BACKGROUND: An upper limit to the strength of shocks that induce fibrillation during the vulnerable period, the upper limit of vulnerability (ULV), has been shown to exist in both humans and animals. The purpose of this study was to compare ULV and defibrillation (DF) probability of success curves for a clinically useful nonthoracotomy lead system. METHODS AND RESULTS: Sixteen pentobarbital-anesthetized pigs were studied. Single-capacitor biphasic waveforms with both phases 5.5 ms in duration were used for ULV and DF testing. A right ventricular catheter electrode served as first-phase cathode and a superior vena cava catheter electrode coupled with a cutaneous R2 patch electrode served as common first-phase anodes. A pacing catheter was placed in the right ventricle to deliver a train of 15 S1 stimuli at a pacing interval of 250 to 300 ms. A ULV shock was delivered on the peak of the T wave as measured from the surface ECG; if ventricular fibrillation was induced, a DF shock was delivered after 10 seconds of fibrillation. Shock voltages were determined by an up-down protocol. Ventricular fibrillation was induced an average of 53 times in each animal. The composite data indicate that below V97, that is, the voltage that leaves the animal in normal sinus rhythm 97% of the time when delivered on the peak of the T wave or the voltage that defibrillates 97% of the time, ULV is lower than DF. ULV and DF became significantly correlated at V80 and maximally correlated at V97. Even at V97, however, ULV and DF differed by more than 100 V in 2 of the 16 animals. CONCLUSIONS: ULV approximately equaled DF at V97. This is fortunate because it is clinically important to set the device voltage at the uppermost portion of the probability of success curve. Estimating DF V97 from ULV V97 would reduce the number of fibrillation inductions needed to establish defibrillation shock strength requirements. However, the large difference between ULV V97 and DF in a few animals indicates that further improvement and testing of algorithms for determining ULV V97 must be developed before the technique is used clinically.


Asunto(s)
Cardioversión Eléctrica , Fibrilación Ventricular/terapia , Animales , Estimulación Cardíaca Artificial , Cardioversión Eléctrica/instrumentación , Cardioversión Eléctrica/métodos , Cardioversión Eléctrica/estadística & datos numéricos , Electrodos , Femenino , Masculino , Probabilidad , Porcinos , Toracotomía , Fibrilación Ventricular/fisiopatología
17.
Pneumologie ; 44 Suppl 1: 232-3, 1990 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-2367374

RESUMEN

In conditions associated with stimulation of cellular immunity and enhanced macrophage activity, for example, in viral infections, neopterin is elevated. Acute exacerbations of bronchial asthma--in particular in the case of intrinsic asthma--are frequently precipitated by viral infections of the upper airways. In both extrinsic and intrinsic asthma, neopterin is normal in the stable phases. In the exacerbation phase with signs of infection of the upper airways, however, neopterin in significantly elevated both in the serum and in the urine. In contrast, during and following positive inhalative provocation testing with histamine, allergens and aspirin, no increase in neopterin is to be observed.


Asunto(s)
Asma/inmunología , Biopterinas/análogos & derivados , Pruebas de Provocación Bronquial/métodos , Activación de Linfocitos/inmunología , Activación de Macrófagos/inmunología , Infecciones del Sistema Respiratorio/inmunología , Biopterinas/orina , Humanos , Neopterin , Linfocitos T/inmunología
18.
S Afr Med J ; 62(9): 295-6, 1982 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-6955966

RESUMEN

A case of acute myelomonocytic leukaemia in pregnancy with successful outcome is reported. Aspects of management are reviewed, especially with regard to expected complications following cytostatic therapy and the effects on both mother and fetus. The need to determine the optimal time for elective delivery is emphasized. The seasons for formation of an international tumour registry are outlined. The disease can no longer be regarded as invariably fatal for mother and child.


Asunto(s)
Leucemia Mieloide Aguda/terapia , Complicaciones Hematológicas del Embarazo/terapia , Adulto , Citarabina/uso terapéutico , Femenino , Humanos , Leucemia Mieloide Aguda/tratamiento farmacológico , Embarazo , Tioguanina/uso terapéutico
19.
S Afr Med J ; 66(22): 855-8, 1984 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-6542254

RESUMEN

A true XX hermaphrodite presenting in adulthood with male sex gender identity was found to have separate vaginal and urethral openings in the perineum. A total vaginectomy was performed at the same time as total abdominal hysterectomy and gonadectomy because the vaginal opening would interfere with a urethroplasty to repair the hypospadias and chordee phallus. During this procedure prostatic tissue was excised in the area of the anterior vaginal wall adjacent to the urethra. Recommendations regarding this rare XX true hermaphroditism are put toward and observations on some bizarre features of the entity are made. The authors plead for the formation of a national register to study this interesting condition.


Asunto(s)
Trastornos del Desarrollo Sexual/patología , Adulto , Femenino , Humanos , Masculino , Ovario/patología , Testículo/patología
20.
Br J Obstet Gynaecol ; 91(2): 187-92, 1984 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-6696863

RESUMEN

The association between pre-operative serum carcinoembryonic antigen (CEA) and liver scanning employing technetium (99mTc)-tin colloid was investigated in 30 women subsequently proven to have primary epithelial ovarian carcinoma to determine whether these two investigations improve the detection of hepatic metastases. The upper limit of normal for CEA (greater than or equal to 5 ng/ml) did not represent the optimal levels for use in predicting ovarian carcinoma nor the presence of liver metastases. But with CEA levels greater than 10 ng/ml sensitivity for liver metastases was 57%. Liver scanning alone demonstrated metastases in five out of seven patients (71%) with parenchymal liver metastases. The combination of CEA and liver scan was positive in six out of these seven patients (86%).


Asunto(s)
Antígeno Carcinoembrionario/análisis , Neoplasias Hepáticas/secundario , Neoplasias Ováricas/diagnóstico , Compuestos de Tecnecio , Compuestos de Estaño , Adulto , Anciano , Femenino , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/diagnóstico por imagen , Persona de Mediana Edad , Cintigrafía , Tecnecio , Estaño
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