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The vast majority of goat skin processed by traditional tanneries comes from small rural producers. Thus, with the predominance of rustic creation, slaughter, and skinning methods, the batches of hides processed by tanneries have a very heterogeneous quality. Thus, there is a need to categorize the samples according to the quantity and location of defects. The categorization process is subjective and strongly influenced by the experience of the professional classifier, causing a lack of homogeneity in the composition of the goat hide lots for sale. Aiming to reduce failures in the categorization of goatskin samples, the authors investigate the application of computer vision and artificial intelligence on a set of previously categorized wet blue goatskin photographic samples. That said, is analyzed the capacity of different classifiers, with different paradigms, in detecting defects in goatskin samples and in categorizing these samples among seven possible quality levels. A hit rate of 95.9% was achieved in detecting defects and 93.3% in categorizing quality levels. The results suggest that the proposed methodology can be used as a decision aid tool in the qualification process of goat leather samples, which can reduce sample labeling errors.

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BACKGROUND: Atrioventricular nodal reentrant tachycardia (AVNRT) is probably the most common form of paroxysmal supraventricular tachycardia. Percutaneous catheter ablation is a technique to interrupt cardiac conduction pathways selectively. The anesthetist is challenged to provide a safe anesthetic which takes into account the electrophysiologist's requirements for minimal cardiac conduction interference. Propofol is an ideal drug. However, previous studies have shown that the infusion of propofol has sometimes been associated with bradyarrhythmias or conversion of arrhythmias to sinusal rhythm. The purpose of this report is to verify the interferences of propofol in the electrophysiological properties of the atrioventricular (AV) node conduction system in patients with AVNRT. METHODS: Patients were randomly assigned to receive either a placebo or propofol at sedative doses. An electrophysiological study was performed consisting of measuring the anterograde (AERPFP) and retrograde effective refractory period of the fast (RERPFP) and the anterograde effective refractory period of the slow (AERPSP) AV nodal pathway. Reciprocating tachycardia was induced and the cycle length (CL) and atrial-His (AH), His-ventricular (HV), and ventriculoatrial (VA) intervals were measured. RESULTS: Propofol did not cause alteration (P > 0.05) in the AERPFP or RERPFP and the AERPSP AV nodal pathway. The AH, HV, and VA intervals were not affected. Sustained reciprocating tachycardia could be induced in the all patients. All slow pathways were successfully identified and ablated. CONCLUSION: Propofol has no effect on the electrophysiological properties of the AV node conduction system. It is thus a suitable anesthetic agent for use in patients undergoing ablative procedures.

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A eletrofisiologia cardíaca, responsável pelo estudo das arritmias cardíacas, é uma das áreas do conhecimento que vem apresentando o maior crescimento atualmente. Neste artigo, apresentamos uma série de trabalhos desenvolvidos por nós ou nos quais participamos, descrevendo contribuições ao conhecimento atual. Em fibrilação atrial, estudamos características da resposta ventricular, uso da amiodarona associada ou não ao verapamil, utilidade da ablação da junção atrioventricular e implante de marca-passo na melhora da qualidade de vida. Sobre marca-passos, avaliamos qualidade de vida e capacidade funcional obtidas por diferentes modos de programar o marca-passo, descrevemos pacientes com marca-passo dupla-câmara e insuficiência cardíaca com o maior benefício da estimulação cardíaca. Sobre ablação por radiofreqüência, descrevemos complicação transitória incomum, além de mostrar aspectos relacionados à segurança do procedimento em nosso meio. Sobre métodos não-invasivos, avaliamos métodos sensibilizadores do teste de inclinação através do uso de drogas, aspectos terapêuticos farmacológicos e não-farmacológicos da síncope vaso-vagal, características da transmissão transtelefônica de traçados monitorados por registrador de eventos e diferença de holter solicitado por cardiologista e não-cardiologistas.

Cardiac electrophysiology, which is responsible for the study of cardiac arrhythmias, has been currently presenting an exponential growth. In this paper, we describe a series of studies either developed by us or to which we collaborated, describing contributions to current knowledge. Regarding atrial fibrillation, we have studied characteristics of ventricular response, use of amiodarone associated or not to verapamil, usefulness of atrioventricular junction ablation and pacemaker implant in the improvement in quality of life. Regarding pacemakers, we have evaluated quality of life and functional capacity obtained by different pacemaker modes, as well as described the best ways to program a dual-chamber pacemaker in cardiac heart failure patients. Regarding radiofrequency ablation, we have described an uncommon transient minor complication, besides reporting aspects related to the safety of the procedure in our region. Regarding noninvasive investigation methods, we have evaluated the use of drugs to increase tilt table test sensibility, pharmacological and nonpharmacological methods in vasovagal syncope treatment, characteristics of electrocardiogram tracings obtained by event recorders transtelephonic transmission and differences between Holter monitoring ordered by cardiologist and other medical professionals.

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OBJECTIVES: In the present study, we evaluated sinus and atrioventricular (AV) node electrophysiology of endurance athletes and untrained individuals before and after autonomic pharmacologic blockade. BACKGROUND: Endurance athletes present a higher prevalence of sinus bradycardia and AV conduction abnormalities, as compared with untrained individuals. Previous data from our laboratory suggest that nonautonomic factors may be responsible for the longer AV node refractory period found in well-trained athletes. METHODS: Six aerobically trained male athletes and six healthy male individuals with similar ages and normal rest electrocardiograms were studied. Maximal oxygen uptake (O(2)max) was measured by cardiopulmonary testing. The sinus cycle length (SCL), AV conduction intervals, sinus node recovery time (SNRT), Wenckebach cycle (WC) and anterograde effective refractory period (ERP) of the AV node were evaluated by invasive electrophysiologic studies at baseline, after intravenous atropine (0.04 mg/kg) and after addition of intravenous propranolol (0.2 mg/kg). RESULTS: Athletes had a significantly higher O(2)max as compared with untrained individuals. The SCL was longer in athletes at baseline, after atropine and after the addition of propranolol for double-autonomic blockade. The mean maximal SNRT/SCL was longer in athletes after atropine and after propranolol. The WC and anterograde ERP of the AV node were longer in athletes at baseline, after atropine and after propranolol. CONCLUSIONS: Under double-pharmacologic blockade, we demonstrated that sinus automaticity and AV node conduction changes of endurance athletes are related to intrinsic physiology and not to autonomic influences.

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Num estudo aberto, näo comparativo, foram avaliados 10 doentes portadores de hipertensäo arterial primária, tratados com uma associaçäo de metipranolol e butizida, através de uma monitorizaçäo ambulatorial da pressäo arterial. Após 1 mês com placebo, os indivíduos receberam a associaçäo em estudo durante 4 semanas. Os resultados mostraram que tanto a medida casual como a medida pela monitorizaçäo ambulatorial de 24 horas, e mesmo as médias dos períodos dia e noite foram significativamente menores que no período sem drogas ou com placebo. Da mesma forma, a variabilidade os níveis tensionais diminuiu significativamente após o início do tratamento. A tolerabilidade foi muito boa, com ausência de efeitos colaterais importantes. Concluiu-se que a associaçäo em estudo é um eficaz anti-hipertensivo durante o período de 24 horas, näo alterando o ritmo fisiológico circadiano da pressäo arterial

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Estudar a eficácia anti-hipertensiva da nitrendipina por 24 horas. Vinte indivíduos com hipertensäo arterial primária leve a moderada. O estudo foi do tipo duplo-cego, com 90 dias de duraçäo. Após 15 dias sem drogas, os pacientes forma divididos aleatoriamente em dois grupos: 1) uso de nitrendipina 20 mg por 30 dias; 2) uso de placebo por 30 dias. Após outros 15 dias de "wash out", os grupos foram cruzados. A pressäo arterial foi avaliada por monitorizaçäo ambulatorial de 24 horas. A pressäo arterial sistólica média das 24 horas, da fase com nitrendipina foi significativamente (p > 0,0001) menor (127,7 ñ 8 mmHg) do que a com placebo (139,2 ñ 8 mmHg) do que a com placebo (139,2 ñ 8 mm Hg); a pressäo arterial diastólica média de 24 horas foi significativamente (p < 0,0001) menor com nitrenpidina (84,6 ñ 4 mmHg) do que com placebo (90,7 ñ 5 mmHg). As demais médias de 24 horas näo diferiram significativamente entre si. A nitrendipina mostrou-se anti-hipertensivo seguro e eficaz durante as 24 horas. A droga reduz as cifras tensionais mantendo o ritmo circadiano da pressäo arterial sem produzir períodos de hipotensäo arterial

Purpose: To evaluate the efficacy of nitrendipine 20 mg OD in mild to moderate hypertensive subjects. Patients and Methods: Twenty patients followed for 90 days. The protocol was a double blind placebo control trial using 24 hours ambulatory blood pressure monitoring system for pressure and heart rate observations. After 15 days without any drug patients were randomly assigned to the study divided into two subgroups: one remained 30 days using placebo and the other nitrendipina. After a new 15 days washout period there was a cross over of the study groups and then other 30 days of follow-up. Results: The 24 hours mean systolic blood pressure decreased (p < 0.0001) with nitrendipine (127.7 ± 8 mmHg) in relation to placebo (139.2 ± 8 mmHg); the mean diastolic blood pressure decreased (p < 0.0001) with nitrendipine (84.6 ± 4 mmHg) in relation to placebo (90.7 ± 5 mmHg). There were no signifcant changes on heart rate and body weight. Conclusion: Nitrendipine seems to be a safe and efficient antibypertensive agent for 24 hours blood pressure control. The drug can decrease blood pressure levels without signifcant changes over the circadian pattern of the 24 hours blood pressure curve and without unwanted drop of blood pressure levels.

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