A description of cattle movements in two departments of Buenos Aires province, Argentina.

We present a descriptive analysis of cattle movement information retrieved from the Argentinean animal movement database for two departments in the province of Buenos Aires during 2004. For each quarter of the year (January to March, April to June, July to September, and October to December) we report the number of on- and off-farm movement events for the purpose of finishing. Our analyses show that the distribution of the number of finishing-related movement events per farm was skewed, with the majority of farms reporting at least 1 and less than 5% of farms of reporting greater than 15 finishing related movement events throughout the year. The frequency of finishing-related movement events varied over time, with a 1.2-1.8-fold increase in reported movement events from April to September, compared with the rest of the year. These analyses indicate that cattle movement patterns in these departments are dependent on the relative mix of constituent cattle enterprise types. Departments with a mixture of breeding and finishing enterprises behave as potential recipients and distributors of infectious disease, whereas departments comprised of primarily finishing enterprises are predominantly recipients of infectious disease, rather than distributors. Data integrity audits of the Argentinean animal movement database, on a regular or intermittent basis, should allow the presence of bias in these data to be quantified in greater detail.

Serious eye injuries caused by bottles containing carbonated drinks.

AIM: To analyse serious eye injuries caused by bottles containing pressurised drinks. METHODS: Retrospective review of the databases of US, Hungarian, and Mexican eye injury registries. RESULTS: In the combined database (12 889 injuries), 90 cases (0.7%) were caused by bottle tops or glass splinters. The incidence varied widely: 0.3% (United States), 3.1% (Hungary), and 0.9% (Mexico), as did the agent. Champagne bottle corks were responsible in 20% (United States), 71% (Hungary; p<0.0001), and 0% (Mexico). Most eyes improved, but 26% remained legally blind. CONCLUSIONS: The presence of warning labels on champagne bottles appears to reduce cork related eye injuries, as does using plastic bottles and caps.

Resultados clínicos de la resincronización ventricular en pacientes con insuficiencia cardíaca severa / Results of intraventricular resynchronization in patients with severe cardiac failure

BACKGROUND: Intraventricular resynchronization with pacemakers is a promising therapy for patients with refractory cardiac failure and intraventricular conductions delay. However its long term effects are not well known. AIM: To report the results of this therapy in patients with cardiac failure. PATIENTS AND METHODS: Fourteen patients (11 male), whose mean age was 68 years, with a severe and refractory cardiac failure, have been treated in our unit using intraventricular resynchronization with pacemakers. Eight had a coronary heart disease and six a dilated myocardiopathy. The pacemaker was implanted transvenously, with conventional stimulation in atrium and right ventricle. The left ventricle was stimulated through an epicardial vein, accessed through the coronary sinus. RESULTS: In one patient the high thresholds did not allow a left ventricular stimulation. In the other 13 patients, a clinical improvement was observed in 11 (85 per cent), that has been sustained for a mean of 8.2 months. The ejection fraction improved form 23.5 to 32.4 per cent (p < 0.001), the 6 min walking test improved from 347 to 437 m (p = 0.003) and the functional capacity changes from 3.3 to 2.7 (p < 0.001). Three patients died during follow up. One was the patient in whom the stimulation failed and two had a sudden death. No complications of the procedure were observed. CONCLUSIONS: In this series, intraventricular resynchronization with pacemakers was effective in 11 of 13 patients, improving functional capacity and ejection fraction. Sudden death could be avoided adding a defibrillator to the pacemaker system.

Early detection of acute allograft rejection by linear and nonlinear analysis of heart rate variability.

OBJECTIVE: The first months after orthotopic heart transplantation are associated with the highest risk of acute allograft rejection. This study explores the utility and reliability of linear and novel nonlinear metrics of heart rate variability as predictors of graft rejection. The underlying hypothesis is that the transplanted heart, in response to inflammatory mediators, alters the dynamic properties of its rhythm-generating system. METHODS: In a cross-sectional study of 45 patients who had undergone heart transplantation, spanning a period of 4 months after the operation, heart rate variability was examined by time- and frequency-domain analysis. The nonlinear features of heart rate variability were studied by computing a pointwise correlation dimension of R-R interval time series. The results of heart rate variability analysis were compared with those of endomyocardial surveillance biopsy studies using the International Society for Heart and Lung Transplantation scoring system. RESULTS: Duration of heart transplantation itself exhibited a significant (P<.05) association with the onset of rejection. Specific predictors of acute rejection based on heart rate variability were identified, including shortening of the R-R interval (from 700 +/- 68 to 648 +/- 72 ms), an increase in the ratio of low-frequency (0.04-0.15 Hz) to high-frequency (0.15-0.40 Hz) spectral power (from 0.3 +/- 0.2 to 0.6 +/- 0.4), and a decrease in pointwise correlation dimension values (from 1.7 +/- 0.7 to 0.9 +/- 0.3 units). Multivariable logistic regression analysis (R (2) = 0.4) revealed that the only significant independent risk predictors were pointwise correlation dimension (odds ratio, 2.2 per 0.1 unit) and duration of heart transplantation (odds ratio, 1.7 per week). CONCLUSION: Nonlinear measures of heart rate variability provide noninvasive means for identifying patients undergoing cardiac transplantation with acute rejection, thereby enabling the assessment of the time-dependent adaptive response of the donor heart to its host.

The brain decade in debate: I. Neurobiology of learning and memory.

This article is a transcription of an electronic symposium in which some active researchers were invited by the Brazilian Society for Neuroscience and Behavior (SBNeC) to discuss the last decade's advances in neurobiology of learning and memory. The way different parts of the brain are recruited during the storage of different kinds of memory (e.g., short-term vs long-term memory, declarative vs procedural memory) and even the property of these divisions were discussed. It was pointed out that the brain does not really store memories, but stores traces of information that are later used to create memories, not always expressing a completely veridical picture of the past experienced reality. To perform this process different parts of the brain act as important nodes of the neural network that encode, store and retrieve the information that will be used to create memories. Some of the brain regions are recognizably active during the activation of short-term working memory (e.g., prefrontal cortex), or the storage of information retrieved as long-term explicit memories (e.g., hippocampus and related cortical areas) or the modulation of the storage of memories related to emotional events (e.g., amygdala). This does not mean that there is a separate neural structure completely supporting the storage of each kind of memory but means that these memories critically depend on the functioning of these neural structures. The current view is that there is no sense in talking about hippocampus-based or amygdala-based memory since this implies that there is a one-to-one correspondence. The present question to be solved is how systems interact in memory. The pertinence of attributing a critical role to cellular processes like synaptic tagging and protein kinase A activation to explain the memory storage processes at the cellular level was also discussed.

The brain decade in debate: I. Neurobiology of learning and memory

This article is a transcription of an electronic symposium in which some active researchers were invited by the Brazilian Society for Neuroscience and Behavior (SBNeC) to discuss the last decade's advances in neurobiology of learning and memory. The way different parts of the brain are recruited during the storage of different kinds of memory (e.g., short-term vs long-term memory, declarative vs procedural memory) and even the property of these divisions were discussed. It was pointed out that the brain does not really store memories, but stores traces of information that are later used to create memories, not always expressing a completely veridical picture of the past experienced reality. To perform this process different parts of the brain act as important nodes of the neural network that encode, store and retrieve the information that will be used to create memories. Some of the brain regions are recognizably active during the activation of short-term working memory (e.g., prefrontal cortex), or the storage of information retrieved as long-term explicit memories (e.g., hippocampus and related cortical areas) or the modulation of the storage of memories related to emotional events (e.g., amygdala). This does not mean that there is a separate neural structure completely supporting the storage of each kind of memory but means that these memories critically depend on the functioning of these neural structures. The current view is that there is no sense in talking about hippocampus-based or amygdala-based memory since this implies that there is a one-to-one correspondence. The present question to be solved is how systems interact in memory. The pertinence of attributing a critical role to cellular processes like synaptic tagging and protein kinase A activation to explain the memory storage processes at the cellular level was also discussed

[Implantable defibrillators in the management of malignant ventricular tachyarrhythmias. Experience at the Arrhythmia National Center]. / Desfibrilador implantable en el manejo de taquiarritmias ventriculares malignas. Experiencia del Centro Nacional de Arritmias.

BACKGROUND: Implantable defibrillators are the most effective means to prevent sudden death in patients with malignant ventricular tachyarrhythmias. The availability of this type of devices is limited in Chile, due to their high price. AIM: To report the first patients treated with implantable defibrillators in our hospital. PATIENTS AND METHODS: Nine males and one female aged 13 to 65 years old are reported. Three presented with ventricular fibrillation (presenting out of the hospital in three) and the rest had ventricular tachycardia resistant to drugs or radiofrequency ablation. RESULTS: All implants were performed using intracardiac electrodes. The generator was implanted in the pectoral region in nine and in the abdomen in one. A successful defibrillation was obtained with less than 15 J in four patients, with 20 J in three and with 24 J in three. There were no complications during the procedure. After a 12 months follow up, four patients have been treated by the implantable device. One of these subjects had a ventricular fibrillation in two occasions. One patient died of a bronchopneumonia two years after the implant. CONCLUSIONS: Implantable defibrillators are an effective therapy for the treatment of malignant ventricular arrhythmias with a high risk of sudden death.

[Sudden death due to recuperated ventricular fibrillation: Brugada syndrome?]. / Muerte súbita por fibrilación ventricular recuperada: síndrome de Brugada?

We report a 47 years old male who was recuperated from a sudden death, and in whom the cardiological assessment showed a right bundle branch block and a fluctuating ST segment elevation V1 to V3. During the electrophysiological study, a polymorphic tachycardia and a ventricular fibrillation were induced. Procainamide administration enhanced ST segment alterations in right precordial leads, and isoproterenol normalized the EKG. All these disturbances are similar to the condition described by Brugada brothers. The patient was treated with an internal implantable defibrillator, without the use of antiarrhythmic drugs and is well after four months of follow up.

[Low energy transcatheter atrial defibrillation in one patient with refractory atrial fibrillation]. / Desfibrilación auricular transcatéter con baja energía en un caso de fibrilación auricular crónica refractaria.

Most cases of atrial fibrillation are converted with antiarrhythmic medications or external electric defibrillation. However, in some refractory patients, an internal transcatheter defibrillation must be attempted. We report a 50 years old male with an atrial fibrillation of one year duration that was refractory to pharmacological treatment and in whom external cardioversion was unsuccessful. After the application of a bifasic shock of 10 joules between a catheter in the right atrium and another one located at the coronary sinus, the patient was converted to sinus rhythm. At two months of follow up, the patient continues in sinus rhythm.

Potassium intake and cardiovascular reactivity in children with risk factors for essential hypertension.

OBJECTIVES: Our study objectives were as follows: (1) to determine whether urinary excretion of potassium is lower in black than in white children, (2) to determine whether cardiovascular reactivity (CVR) varies inversely with dietary intake of potassium, and (3) to confirm that CVR is greater in black than in white children, and in children with a family history of hypertension than in those without such a history. STUDY DESIGN: Baseline measurements included 24-hour urinary sodium, potassium, and creatinine levels and food intake (by questionnaire). Resting and stress blood pressure were measured during blood sampling, cold water foot immersion, and a video game before and after 1 week each of supplementation with potassium citrate, 1.5 mmol/kg per day, and placebo administered in random order. RESULTS: Thirty-nine children aged 7 to 15 years were studied. White subjects had higher baseline excretion of potassium than black subjects (p < 0.001) and higher vegetable intake (p < 0.01), which were positively correlated (r = 0.53, p < 0.001). At baseline, the 24-hour urinary potassium/creatinine ratio varied inversely with diastolic CVR to the video game stressor in white children (r = -0.55, p = 0.02). Cardiovascular reactivity was not attenuated measurably by potassium supplementation compared with placebo. The CVR was greater in children with a family history of hypertension than in those without, but was not greater in black children than in white children. CONCLUSIONS: The urinary potassium/creatinine ratio is higher in white than black children because their intake of vegetables is greater; dietary potassium intake may modulate CVR, particularly in white children with a family history of hypertension, but may need to be supplemented for more than 1 week to demonstrate attenuation of CVR; and a family history of hypertension may be a stronger predictor of enhanced CVR than is race.

Leflunomide and malononitrilamides.

Leflunomide is a new immunomodulatory drug that is effective in experimental models of autoimmune diseases and in allo or xenotransplantation. In a phase II clinical trial, leflunomide showed high tolerability and efficacy in patients with advanced rheumatoid arthritis. The immunomodulatory activity of leflunomide is attributed to its primary metabolite A77 1726, which is a malononitrilamide. The in vitro and in vivo mechanisms of action of this class of compounds are not defined completely. Several malononitrilamide analogues and A77 1726 inhibit T- and B-cell proliferation, suppress immunoglobulin production, and interfere with cell adhesion. Although no central molecular mechanism of action has been proposed to explain all the effects of the malononitrilamides, the inhibition of de novo pyrimidine biosynthesis and of cytokine- and growth factor receptor-associated tyrosine kinase activity are leading hypotheses for the effects of A77 1726 on T- and B-cell proliferation and function. Leflunomide is effective when administered in daily dosages of 10 mg and 25 mg to patients with active rheumatoid arthritis. The improved efficacy of a 25 mg dose is associated with a higher incidence of adverse effects (gastrointestinal symptoms, weight loss, allergic reactions, skin rash, and reversible alopecia). Because of the long plasma half-life of A77 1726 (11 to 16 days), loading doses are necessary to achieve steady state concentrations. Phase III randomized, placebo-controlled trials that use daily dosages of 10 mg or 20 mg are under way in the United States and Europe to confirm and extend the results of the phase II study. Malononitrilamide analogues of A77 1726 are being evaluated for immunosuppressive efficacy in preclinical models of transplantation. If these analogues show efficacies and therapeutic indexes that are similar to leflunomide in these models and that have shorter half-lives than A77 1726 in phase I trials, the preclinical and phase I data will be used to select the analogues for phase II trials in organ transplant recipients.

Leflunomide and malononitriloamides.

Leflunomide is a new immunomodulatory drug effective in experimental models of autoimmune diseases and allo- or xenotransplantation. In a Phase II clinical trial leflunomide has shown high tolerability and efficacy in patients with advanced rheumatoid arthritis. The immunomodulatory activity of leflunomide is attributed to its primary metabolite, A77 1726, a malononitriloamide. The in vitro and in vivo mechanisms of action of this class of compounds remain to be completely defined. A77 1726 and several malononitriloamide analogues inhibit T- and B-cell proliferation, suppress immunoglobulin production, and interfere with cell adhesion. While no one central molecular mechanism of action has been proposed to explain all the effects of the malononitriloamides, inhibition of de novo pyrimidine biosynthesis and inhibition of cytokine- and growth factor-receptor associated tyrosine kinase activity are leading hypotheses for the effects of A77 1726 on T- and B-cell proliferation and function. Leflunomide is effective when administered at daily doses of 10 and 25 mg to patients with active rheumatoid arthritis. The improved efficacy at the 25 mg dose is associated with a higher incidence of adverse effects (gastrointestinal symptoms, weight loss, allergic reactions, skin rash, and reversible alopecia). Due to the long plasma half-life of A77 1726 (11-16 days), loading doses are required to achieve steady-state concentrations. Phase III randomised, placebo-controlled trials using daily doses of 10 or 20 mg are underway in the US and Europe to confirm and extend the results of the Phase II study. Malononitriloamide analogues of A77 1726 are being evaluated for immunosuppressive efficacy in preclinical models of transplantation, because these compounds have a shorter half-life in animals than A77 1726. If these analogues show efficacies similar to leflunomide in these models and have shorter half-lives than A77 1726 in Phase I trials, the preclinical and Phase I data will be used to select the analogues for Phase II trials in organ transplant recipients.

Cognitive correlates of long-term cannabis use in Costa Rican men.

BACKGROUND: Cognitive correlates of long-term cannabis use have been elusive. We tested the hypothesis that long-term cannabis use is associated with deficits in short term memory, working memory, and attention in a literate, westernized culture (Costa Rica) in which the effects of cannabis use can be isolated. METHODS: Two cohorts of long-term cannabis users and nonusers were studied. Within each cohort, users and nonusers were comparable in age and socioeconomic status. Polydrug users and users who tested positive for the use of cannabis at the time of cognitive assessment after a 72-hour abstention period were excluded. The older cohort (whose age was approximately 45 years) had consumed cannabis for an average of 34 years, and comprised 17 users and 30 nonusers, who had been recruited in San José, Costa Rica, and had been observed since 1973. The younger cohort (whose age was approximately 28 years) had consumed cannabis for an average of 8 years, and comprised 37 users and 49 nonusers. Short-term memory, working memory, and attentional skills were measured in each subject. RESULTS: Older long-term users performed worse than older nonusers on 2 short-term memory tests involving learning lists of words. In addition, older long-term users performed worse than older nonusers on selective and divided attention tasks associated with working memory. No notable differences were apparent between younger users and nonusers. CONCLUSION: Long-term cannabis use was associated with disruption of short-term memory, working memory, and attentional skills in older long-term cannabis users.

Wuchereria bancrofti in a Haitian immigrant.

A case of Wuchereria bancrofti filariasis was recently seen in a Haitian immigrant in Charleston, SC. The Caribbean area is a known endemic focus for this organism. With the increased numbers of immigrants from that area, it is likely that other such cases will be seen in the US.

Casuistica de algunas opiniones, actitudes y practicas en educacion sanitaria en el consultorio "La Reina" del Servicio de Salud Metropolitano Oriente en anos 1979 - 1982. / Casuistic of some opinions, actitudes and practices, in health education in the ambulatory \"La Reina\" of the Servicio de Salud Metropolitano Oriente in years 1979 - 1982

Se presentan y analizan en este estudio los resultados de encuestas efectuadas en muestras de integrantes del equipo de Salud y beneficiarios del Consultorio "La Reina", acerca de la entrega y captacion de contenidos educativos. Esta investigacion representa un aporte significativo a la evaluacion de las acciones educativas y la importancia que debe concederseles en los problemas de salud, si bien es menester intensificarlas o buscar metodos nuevos que nuevos que provean mayor efectividad, sin desconocer la existencia de factores limitantes ajenos al sector salud