Effects of gibberellic acid concentration and fruit maturation stage on seed germination and vigor of pitahaya seedlings.

With increased interest in cultivation, the study of white-fleshed pitahaya (Selenicereus undatus (Haw.) D.R. Hunt, Cactaceae family) seedling production is of fundamental importance in the search for novel techniques to increase cultivation and guarantee homogeneous and productive orchards. The present study investigated the influence of various gibberellic acid (GA3) concentrations and fruit maturation stages on seed germination and vigor of white-fleshed pitahaya seedlings, considering the physiological quality of seedlings produced to support genetic breeding and conservation programs of the species. White-fleshed pitahaya seeds at two maturation stages (physiologically ripe and maintained at 10 °C in Biochemical Oxygen Demand incubators for three months) were treated with varying GA3 concentrations of 0, 50, 100, and 500 mg/L. We observed the influence of fruit storage on seedling germination, emergence, and growth as a function of GA3 concentration. According to the results, seeds extracted from ripe white-fleshed pitahaya fruits grown under the conditions tested here required GA3 application to increase seedling emergence and vigor, with optimal doses in the 150-300-mg/L range. In the case of pitahaya fruits intended for storage for future seed removal and maintained under the same sowing conditions, the application of higher doses of GA3 was necessary when compared to the previous condition, with a minimum dose of 500 mg/L GA3. The present study shows that the maturation stage of white-fleshed pitahaya fruits intended for seed removal influences the quality of seedlings; therefore, the use of seeds extracted from ripe pitahaya fruits without fermentation is more appropriate for the purpose.

Pheno- and genotyping of Staphylococcus aureus, isolated from bovine milk samples from São Paulo State, Brazil.

In the present study, 87 Staphylococcus aureus isolates obtained from milk samples of 87 cows with mastitis in 6 different municipal districts of 2 regions of Sao Paulo State, Brazil, were compared pheno- and genotypically. Pulsed-field gel electrophoresis (PFGE) analysis of the strains was performed, and PCR was carried out to detect genes for a number of staphylococcal cell surface proteins, exoproteins, and 3 classes of agr genes. Nine distinct S. aureus lineages (LA-LI) were identified by PFGE. The lineages LA and LE, which accounted together for 63 strains (72.2%), were prevalent and had been collected from all of the 6 municipal districts, indicating a broad geographic distribution of these lineages; LB, LC, LD, LF, LG, LH, and LI, however, were isolated sporadically and accounted for 24 strains (27.8%). Some characteristics, like penicillin resistance and the presence of cap8 and agr class II genes, were associated with the prevalent lineages (LA and LE), and penicillin susceptibility and the presence of cna and cap5 genes were associated with sporadic lineages. According to the present results, some S. aureus lineages possess a combination of genes that confer the propensity to cause and disseminate infection, and only a limited number of clones are responsible for the cases of bovine mastitis on the various farms.

[Study of post-myocardial infarction ventricular aneurysms with equilibrium radionuclide angiography. Significance of Fourier analysis]. / Estudo dos aneurismas ventriculares pós-enfarte do miocárdio pela angiografia de radionuclidos de equilíbrio. Importância da análise de Fourier.

The concept of left ventricular aneurysm has been a subject of controversy and it's not yet completely settled. This has some implications on the patients selection for surgery and explains the various non-invasive methods so far developed for the clinical assessment of patients with ventricular aneurysms. Seventy-one patients with ischemic heart disease, 65 with recent myocardial infarction, were studied by equilibrium radionuclide angiography (ERNA) in order to define left ventricular wall motion abnormalities. One hundred ERNA were undertaken, through the usual erytrocites in vivo labelling technic, employing a GE 400 T Gama-Camera GP. Image acquisition was through 400 cardiac cycles, on LAO (30 and 60 degrees) and left lateral. PAGE protocol was employed. Fourier transform was used in the present work to obtain phase and amplitude images, which actually became the main criteria to define aneurysmatic areas. Global ejection fraction, regional wall motion and regional ejection fraction were other parameters investigated. Wall motion abnormalities have been identified in all the 65 patients having suffered a myocardial infarction. Extensive areas of akinesia or localized dyskinesia were present in 40 patients (16.5%), while remainder 25 had just localized hypoakinesia. Phase image enabled the selection of LV areas of contraction delay in 19 of the 40 patients with extensive wall motion abnormalities (Group I). In such Group I we could identify an LV area with contrasting colour, defining the aneurysmatic LV portion. In the order 21 patients with extensive akinesia, no significant changes of colour were present on ventricular phase image (Group II) meaning absence of aneurysm. No phase disturbances were seen in the remainder 25 patients with MI (Group III) and the 6 patients with CAD without MI had normal phase images (Group IV). The percentage of akinetic segments was 39.1 and 35.4 in Group I and II, respectively (p = .53) while it was significantly lower in Group III 17.9%; p < .0001). LV ejection fraction was statistically different in the four groups considered (I = 30.0% +/- 3.7; II = 39.9% +/- 2.9; III = 49.0% +/- 2.5; IV = 62.0% +/- 3.2). The degree of phase delay in aneurysmatic zones was quantified by the phase histogram. Average value of phase for the left ventricle was 129.7 +/- 8.4 degrees, and for the aneurysm it was 238.0 +/- 5.0 with an average phase delay of 104.8 +/- 4.1 degrees. The association of phase and amplitude images and the measurements of phase and amplitude values on the histograms allowed the distinction of akinetic aneurysm (phase delay and low amplitude) from the dyskinetic aneurysms (phase delay and high amplitude). Half of the isotopic diagnosis of aneurysms have been confirmed by classic contrast angiography, and a third of then have undergone surgery. The two dyskinetic aneurysms that have been submitted to aneurysmectomy had pos-operative improvement of LV function. On summary, phase and amplitude analysis by the Fourier method, which is independent of LV geometry, showed that LV regions with high phase values are associated with severe regional wall motion abnormalities and low ejections fractions. The definition of the sequence and amplitude of ventricular contraction allows the distinction of akinetic and dyskinetic aneurysms, anticipating the method as a valid contribution for the screening of patients likely to benefit from aneurysmectomy.

[Secondary prevention in acute myocardial infarction]. / Prevenção secundária no enfarte agudo do miocárdio.

Myocardial infarction is still one of the main causes of mortality and morbidity in Western countries. The advances made in the last 30 years have made it possible to reduce mortality significantly (which is currently below two digits) as well as morbidity. The subject of secondary prevention of myocardial infarction gains particular significance in this context since 10 to 15% of the patients who survive the hospital phase of myocardial infarction die during the first year following discharge and, of these deaths, half occur in the first three months. Therefore, it is necessary to make an early definition of the risk of another coronary event, that is, to make a risk stratification. This should occur throughout hospitalization and should be complete at the time of discharge, never beyond the first weeks of evolution. Bearing in mind the age, sex, coronary risk factors, ischemia persistence, the degree of left ventricular dysfunction and the presence of malignant disrhythmias, there are three risk levels: high; intermediate; and low. An overall approach to secondary prevention of infarction should take into account that, apart from the factors of such high prognostic value (Chapter II) assessed in the definition of risk groups, the measures to reduce reinfarction and sudden death (Chapter III) and the control of the risk factors for heart disease (Chapter IV) should also be considered. The principal late complications of infarction with significant prognostic influence are described in Chapter III: left ventricular dysfunction; rhythm disturbances and residual ischemia. The diagnostic criteria and therapeutic objectives are considered in each of the groups with relevance to consolidated advances according to the modern concept of evidence based medicine, according to international regulations. The grading of scientific evidence into three distinct categories (A, B and C), based on five levels of evidence classified from I to V, is presented accordingly in relation to the therapeutic proposals. Chapter III deals with a set of therapeutic interventions used in secondary prevention because they reduce reinfarction and sudden death: platelet antiaggregants; anticoagulants; Beta blockers; calcium channel blockers; antioxidants and nitrates. A concept of particular clinical significance is presented for each of these groups of drugs. The last part contains an eminently clinical overall review of the principal advances in coronary risk factor control, new therapeutic acquisitions in atherosclerotic disease with natural relevance to hypolipidemic agents and statins, which apart from controlling the plasmatic levels of cholesterol, also stabilize the atherosclerotic plaque and reduce acute coronary events significantly. Apart from dyslipidemia, the classic risk factors are: smoking; hypertension; obesity; diabetes and sedentary life. In each case, reference is made to the general measures and specific approaches, as well as the pharmacological therapy according to evidence based medicine. The recommended attitudes are pointed out. The role of cardiac rehabilitation and postmenopausal hormone replacement therapy are also discussed in the last part of these recommendations, in which the on-going controversy regarding hormone replacement therapy is pointed out in view of the results of more recent clinical trials.

Seroprevalence of bovine leptospirosis in Garanhuns Municipal District, Pernambuco State, Brazil.

The prevalence of Leptospira interrogans serovars in dairy cattle was determined by analyzing 464 serum samples from cows on 15 properties in Garanhuns municipal district, Pernambuco State, Brazil. A microscopic seroagglutination test including 12 serovars of Leptospira interrogans as antigens was used. Samples with titres 100 were considered positive. Two hundred and twenty-one (47.63%) of the samples were positive to one or more serovars. The prevalence of the serovars was hardjo (21.98%), bratislava (15.73%), castellonis (11.64%), tarassovi (10.56%), pyrogenes (1.72%), icterohaemorrhagiae (1.08%), pomona (0.86%), wolffi (0.86%), grippotyphosa (0.86%), djasiman (0.43%), canicola (0.21 %), and copenhageni (0.21%).

Wall motion abnormalities and late ventricular arrhythmia during the predischarge phase of acute myocardial infarction.

BACKGROUND: Left ventricular wall aneurysm is a complication of acute myocardial infarction which has been considered a precipitating factor of cardiac failure and ventricular arrhythmia. We have evaluated the relation between severe left ventricular wall motion abnormalities and ventricular arrhythmia. METHODS: During a two-year period 146 patients admitted to a coronary care unit with acute myocardial infarction were studied. Radionuclide angiography performed within the second and the fourth weeks was used to analyse phase and wall motility changes, and patients were divided into three groups: 1) Hypokinesia and/or akinesia localized to one segment: with no or slight changes in phase image--102 patients; 2) Aneurysm: left ventricular deformity with well-defined chromatic changes in phase image--19 patients; and 3) Dyskinesia and/or extensive akinesia of two or more segments: phase image with diffuse heterogeneous changes--25 patients. Ventricular arrhythmia was studied using Holter electrocardiography taken during the second week of acute myocardial infarction. Three rhythmic profiles were considered: no premature ventricular contractions--41 patients; with three or more than three premature ventricular contractions per hour--38 patients; repetitive premature ventricular contractions--20 patients. RESULTS: Premature ventricular contractions were absent in 31 (30%) of the patients with hypokinesia/localized akinesia vs 8 (42%) of the patients with aneurysm, and vs 2 (8%) of the patients with dyskinesia/extensive akinesia. Premature ventricular contractions were frequent (> or = 3/h) in 22 (22%) of the patients with hypokinesia/localized akinesia vs 4 (21%) of the patients with aneurysm (p = 0.35; NS), and vs 12 (48%) of the patients with dyskinesia/extensive akinesia (p=0.003). Repetitive premature ventricular contractions were present in 10 (10%) of the patients with hypokinesia/localized akinesia vs 2 (11%) of the patients with aneurysm, and vs 8 (32%) of the patients with dyskinesia/extensive akinesia (p=0.008). CONCLUSIONS: We conclude that the presence of aneurysm was not associated with a higher occurrence of ventricular arrhythmia, but patients with dyskinesia/extensive akinesia had a higher occurrence of ventricular arrhythmia, > or = 3 premature ventricular contractions per hour and repetitive premature ventricular contractions. Our results suggest that ventricular arrhythmia is related to functionally severe wall motion abnormalities, and not to anatomical discriminants. This finding leads us to suggest different electrophysiological mechanisms behind these two entities.

[Expansion of infarction, dilatation and ventricular remodelling. Therapeutic potential of angiotensin-converting enzyme inhibitors]. / Expansão de enfarte, dilatação e remodelação ventricular. Potencialidades terapêuticas dos inibidores da enzima de conversão da angiotensina.

Early in the acute phase of myocardial infarction the phenomenon of expansion may occur, with regional thinning and dilatation of necrotic region. This complication may be detected by echocardiography since the first hours of infarction. During the two subsequent weeks, an additional increase of left ventricular volume may occur, due to an increase of length of the infarcted segments and, as well, of the contractile segments which suffer a "volume overload hypertrophy". This is the phenomenon of remodeling. Finally during the first year post infarction, a progressive left ventricular dilatation may develop. This late dilatation seems to be due to an increase of perimeter of the contractile regions only. By the time this topographic changes have occurred, the left ventricle assumes a more spheric configuration. Left ventricular dilatation affects adversely cardiac function, with higher incidences of heart failure and death. Experimental and clinical studies show that, in selected patients, remodeling and ventricular dilatation may be attenuated by the administration of angiotensin-converting-enzyme inhibitors, with better indices of left ventricular function. Final results of several on-going multicenter studies are awaited for; they will allow a better definition of the role of ACE inhibitors on prevention and treatment of left ventricular dysfunction after myocardial infarction.

[Inotropic reserve of the left ventricle in patients with chronic ischemic cardiopathy, studied using adrenaline stimulation. Prognostic significance]. / Reserva inotrópica do ventrículo esquerdo, em doentes com cardiopatia isquémica crónica, estudada pela estimulação com adrenalina. Significado prognóstico.

AIMS: To study by equilibrium radionuclide angiography (ERNA) the cardiac inotropic reserve after a myocardial infarction, and to evaluate its prognostic value. DESIGN: Patients in a chronic status of a myocardial infarction were studied by ERNA at a basal state and after stimulation with epinephrine, in the same session. Left ventricle (LV) functional abnormalities, global and regional, were evaluated. A 3-to-5 years follow-up was done. PATIENTS AND METHODS: Twenty five patients with a post myocardial infarction were included: 19 with an anterior infarction, 2 with an inferior and 4 with a combined one. All patients had LV dysfunction evaluated by Echocardiogram at hospital discharge. Global and regional LV function were studied by ERNA before and after inotropic stimulation, using increasing doses of epinephrine from 4.8 to 12 micrograms/minute. Heart rate and blood pressure were monitored. ERNA acquisition were done on left oblique best-septal and lateral views, over 400 cardiac cycles, using a Gama-camera GE 400AC. Three groups of patients were considered, according with the change of LV global ejection fraction: increments greater than 2%--group A (positive response); changes between +2% and -2% - group B; decreases greater than 2%--group C (negative response). During a 3 to 5 years follow-up, the incidence of major cardiac events was analysed: cardiovascular mortality, angina, left ventricle failure, myocardial reinfarction and coronary artery by-pass graft surgery. RESULTS: LV global function-Inotropic stimulation was done with an average perfusion time of 30.8 minutes, with total doses of epinephrine between 176 and 660 ng. No significant changes of heart rate (5%) or blood pressure (5.3%) occurred. Basal LV global ejection fraction (EF) was 29.2%. Only 2 patients had a normal LV ejection fraction; 14 patients had a severe LV dysfunction (EF less than 30%) and 9 had a moderate reduction of ejection fraction (EF between 30% and 45%). From the 14 patients with EF less than 30%, twelve had an involvement of the LV anterior wall. After stimulation EF value ineditreased in 9 and decreased in one patient. From the 11 patients with EF greater than 30%, 6 experienced a increase of EF and 3 decreased of EF after stimulation. REGIONAL WALL MOTION: Group A--15 patients--75 segments. In this group 39 segments were related to necrotic ECG localization, and 79% of them contributed to EF increase after stimulation. Forty-one segments were not involved by necrosis, and 78% had a positive contribution to EF increase. Six patients had all LV segments contributing to the EF increase after stimulation. The other 9 patients, had 13 segments not responding to stimulation (EF increments greater than 2%): 5 of them were segments related to ECG site of infarction. Group B--6 patients--30 segments. Five patients had 9 segments with a positive contribution to EF after inotropic stimulation.(ABSTRACT TRUNCATED AT 400 WORDS)

[Surgical treatment of variant angina. Apropos of a clinical case]. / Terapêutica cirúrgica na angina variante. A propósito de um caso clínico.

A case of a male 66 years-old patient who presented with a clinical picture of Prinzmetal's variant angina early in the evolution of an acute myocardial infarction is reported. Transient elevation of ST-segment was documented on Holter monitoring in association with angina at rest as well as asymptomatic episodes of ST-segment changes. Significant two-vessels obstructive lesions (left anterior descending and circumflex arteries) was present. As variant angina had several recurrences in spite of medical therapy with nitrates and calcium antagonists, the patient was submitted to coronary by-pass surgery associated to plexectomy. A Thallium myocardial scintigraphy suggests that a peroperative infarction had occurred. The patient was asymptomatic at six months follow-up.

[Role of calcium antagonists in the pharmacologic treatment of heart insufficiency]. / O lugar dos antagonistas do cálcio na terapêutica farmacológica da insuficiência cardíaca.

There has been increasing interest in the use of calcium antagonists as arterial vasodilator agents in the management of patients with congestive heart failure. Because congestive heart failure is mostly secondary to coronary artery disease, calcium antagonist drugs seem particularly appealing because of their anti-ischemic properties. The potent vasodilating action of calcium antagonists decreases impedance and improves ejection phase indexes of left ventricle function. However, these drugs interfere with calcium availability for myocardial contraction, and concern has been expressed about their potential depressant effect on myocardial performance. The net hemodynamic effect depends on the relative vascular versus myocardial potency of each calcium antagonist and on the indirect effects of reflex sympathetic activation. Balance between these factors is still influenced by the intrinsic status of left ventricle of the patient. Generally, the negative inotropic direct effect of the calcium antagonists is counteracted by the beneficial influence of the decrease of systemic vascular resistance. Because of its relatively more pronounced negative inotropic action, verapamil is not advisable in patients with left ventricular failure. Limited experience with diltiazem show no significant negative inotropic action. Nifedipine has been studied in its acute and long term effects. The use of sublingual nifedipine is established in the emergency management of acute pulmonary edema, specially in patients with arterial hypertension, or when acute ventricular dysfunction is associated with mitral or aortic insufficiency. Patients with chronic congestive heart failure have shown after nifedipine an increase in stroke volume and cardiac index at rest and during exercise, as well as decreases of pulmonary capillary wedge pressure during exercise.(ABSTRACT TRUNCATED AT 250 WORDS)

[Congestive heart insufficiency. Evaluation using isotopic methods]. / Insuficiência cardíaca congestiva. Avaliação por métodos isotópicos.

Radioisotopic cardiac studies became, on the last decade, one of the more useful non-invasive methods for the diagnostic evaluation and follow-up of patients with heart disease. Such a contribution of nuclear cardiology is specially noticeable on ischemic heart disease: radionuclide angiography (RNA) allows quantification of left and right ventricular dysfunction, and therefore stands as an ideal technique for the prognostic approach of congestive heart failure. As to diagnosis, RNA is useful in the analysis of regional wall motion abnormalities of ischemic heart disease and detection of ventricular aneurysms. Clinical examples are given of these specific situations. In dilated cardiomyopathies RNA gives not only a measure of ventricular dysfunction, but also a diagnostic information, often definitive, of the diffuse involvement of all left ventricle, and commonly of the right ventricle. Ischemic heart disease, on the other hand, displays different degrees of segmental wall motion impairment together with areas of normal contractility. These aspects are documented with cases of our Registry. Also discussed is the inotropic stimulation technique for the evaluation of the functional reserve of left ventricle in patients with severe rest L.V. dysfunction. Focus is given to the clinical value of isotopic studies for the quantification of valvular regurgitations and pre-operative serial studies in order to define an optimum surgical timing. An attempt is done to grade the practical importance of the different exams of Nuclear Cardiology on the diagnostic and prognostic evaluation on heart disease patients, with a cost benefit relation perspective and comparing with other methods, classic of recent ones, available for the management of patients with heart failure.

[Evaluation of left ventricular function after myocardial infarct using equilibrium radionuclide angiography. 1-year follow-up]. / Avaliação da função ventricular esquerda no pós-enfarte do miocárdio pela angiografia de radionuclidos de equilíbrio. Seguimento de 1 ano.

OBJECTIVE: To study the evolution of left ventricular (LV) function in the 1st year after acute myocardial infarction (MI) and to define its prognostic significance. DESIGN: Patients recovering from acute MI submitted to evaluation of LV function by equilibrium radionuclide angiography (RNA) at the time of discharge, three months later and at 12 months of follow-up. PATIENTS AND METHODS: 93 patients suffering an acute transmural MI were submitted to equilibrium RNA. Studies were taken at time of discharge, 3 and 12 months of follow-up. 19 patients had just the 1st study; in 14 the one year follow-up study was not performed. The other 60 include the group submitted to 1 year follow-up. We used the technic of labelled erytrocites in vivo, with acquisition of the blood pool gated with EKG in left lateral. PAGE protocol from GE has been used for processing of images. RESULTS: Mean global ejection fraction (EF) was 20.6 +/- 8.5% for anterior MI with LV failure and 40.2 +/- 14.5% for those without failure; in inferior MI it was 49.9 +/- 12.3% and for combined MI 30.3 +/- 9.5%. The differences between these values are statistically significant. For the 56 patients in which the 1st and 2nd examination were taken we found no significant differences between the mean values for global EF in the 4 groups previously considered. Conversely, we couldn't find a significant difference between the mean EF in the 4 groups, when we compared the values of early (1st and 2nd examinations) test with those of 12 months follow-up. 10 patients (10.8%) died in the 1 year follow-up. All had global EF lower than normal: 33% of deaths in the group with EF less than 20%; 14% in the subset with EF between 20 and 30%; 8% in the sub-group with EF between 30 and 45%. As far as regional motion is concerned we noticed that changes include both the necrotic and the spared areas. We didn't found significant differences between the contribution of necrotic and viable myocardium to the positive or negative variation of global EF, in the 4 groups of infarction considered. Apical segment seems to have an important contribution for global EF changes, both in anterior and inferior MI. CONCLUSION: In this group of patients with acute MI, followed for 12 months, we noticed a higher degree of LV dysfunction in the group of anterior MI. The values of LVEF measured early after the acute attach, usually at hospital discharge are stable along the follow-up, unless major cardiac episodes develop. All the deaths along the one year follow-up had LV dysfunction with EF below 45%. Prognostic "quod vitam" worsened while EF decreased, with a death rate of 33% in the sub-group with global EF less than 20%, and 28% considering those with EF below 30%. In relation with regional motion we found that changes may be elicited both in the necrotic and spared segments. We emphasize the contribution of the apical area to the changes in global EF.