[Enalaprilat in the prevention of left ventricular hypertrophy induced by isoproterenol]

PURPOSE

To evaluate whether the enalaprilat, angiotensin I enzyme conversion inhibitor, could prevent the left ventricular hypertrophy (LVH) induced by isoproterenol.

METHODS

Seventy two adult Wistar-EPM rats were divided into four groups: CON, control; ENA, treated with enalaprilat (1 mg/kg via subcutaneous (s.c.) for 8 days); ISO, treated with isoproterenol (0.3 mg via s.c. for 8 days) e ENA + ISO, treated with both drugs simultaneously. Each group had the arterial blood pressure, cardiac rate and the left ventricle (LV) weight determined in 10 animals. In 8 animals from each group a small sample was taken from the LV and stained with hematoxyline-eosine and picrosirius for morphometric and ultra-structural studies with optic and transmission electronic microscopy.

RESULTS

The ISO group showed that the LV weight increased 47% in comparison with control. On the other hand the ENA + ISO group showed only 22.1% increase (p < or = 0.05). The morphometric and ultra-structural analyses revealed that isoproterenol induced cardiomyocite hypertrophy and augmented the content of the type I collagen in the cardiac interstitium.

CONCLUSION

Enalaprilat inhibited the isoproterenol action on the cardiomyocite, avoiding partially the LVH and decreasing the content of collagen fibers.

[Organophosphate poisoning and myocardial necrosis]

A man (46 years-old) was admitted to the intensive care unit (ICU) with a history that eight hours before he had voluntarily drank 100 ml of malathion. He complained of a burning pain on the anterior thorax and was confused. His cardiovascular evaluation was normal and his breathing was heavy with some rales on the pulmonary auscultation. He was treated with atropine and contrathion and rapidly evolved into coma. Electrocardiogram showed subendocardial lesion in the inferior wall with diffuse ly altered ventricular repolarization and increase QT interval. During the ICU period his cardiac enzyme levels also raised. The patient died in the 8th day after admission. The pathological evaluation of the heart revealed foci of myocardial necrosis. This is the 1st case of medical literature with histological confirmation of myocardial necrosis from organophosphate intoxication.

Iatrogenic biliary strictures: surgical experience with 39 patients

The authors report their experience with surgical treatment of 39 patients with biliary strictures of iatrogenic origin. Patients were grouped according to the level of obstruction as described by Bismuth, and the type of repair was based on this classification. A total of 45 operations were performed, including those for recurrent strictures: 22 hepaticojejunostomies, 10 Hepp and Couinad's operations, 6 choledochojejunostomies, 3 separate right and left hepaticojejunostomies, 1 hepaticojejunostomy with mucosal graft (Smith's technique), 1 intrahepatic cholangiojejunostomy (Longmire's technique), 1 choledochoduodenostomy and 1 choledochoplasty. Results were considered good if the patient was free of symptoms, jaundice or episodes of cholangitis, with serum alkaline phosphatase less than two-times the normal value. Minimum follow-up period of two years (obtained in 35 patients) was required to evaluate the results. Good results were obtained in 26 of those 30 patients (87%) who underwent only one biliary reconstruction, and in 3 of those 5 (60%) with more than one repair. Overall, 29 patients (83% of those 35) presented good results. The complexity of the surgical treatment of biliary strictures imposes the adoption of measures to prevent lesions to the bile duct. Factors related to the prognosis that must be emphasized are surgeons' individual experience and skills, location of the stricture and diameter of the anastomosis.

[Significance of the exercise test in the assessment of graft patency after myocardial revascularization with arteries only]

Although treadmill exercise testing (TET) has been used to identify ischaemia and determine clinical prognosis after myocardial revascularization, considerable controversy remains on its role in the detection of obstructive lesions of the arterial grafts.

AIM

To assess the value of TET in determining the patency of arterial conduits after coronary bypass surgery with complete revascularization.

METHODS

Twenty five patients - 21 men and 4 women; age 53.7 +/- 8.7 years - submitted to complete myocardial revascularization exclusively with arterial conduits (CABG-A), undergoing coronary angiography and a symptomlimited TET (Bruce protocol) within 9 months after CABG-A. Angiograms were visually classified in 2 groups (Group I - conduits without lesions, n = 14; Group II > 50% stenosis or occlusion of > or = 1 conduit, n = 11). Clinical characteristics and the following parameters of the TET were compared: total exercise time (ETime); metabolic equivalents (METS); % of predicted maximal heart rate (% MHR); exercise-induced ST depression (decreases ST); and occurrence of angina. The arterial conduits used were: left internal mammary artery -24-; right internal mammary artery -11-; gastroepiploic artery -14-.

RESULTS

There were no differences in age, gender, left ventricular systolic function, severity of coronary artery disease, and number of conduits per patient. Group I attained superior values for the following parameters: ETime (p < 0.01) and METS (p < 0.01). Among Group II there were more patients with angina (p = 0.03). Fourteen patients exceeded 8 METS (11 from Group I and 3 from Group II - p = 0.002-). There was no statistical difference among the number of patients with ST depression during exercise.

CONCLUSIONS

After CABG-A the exercise tolerance seems to be related with the patency of the conduits and may play an important role in the detection of graft abnormalies. On the contrary, exercise-induced ST depression had low specificity in detecting obstructive lesions of the conduits.

Malaria vaccine trials: the missing qualitative data

Recent population-based efficacy trials of the synthetic malaria vaccine SPf66 have shown restricted, if any, clinical protection against Plasmodium falciparum infection. Despite the well-established role of antibodies in effector responses against asexual blood-stage malaria parasites, the titres of anti-SPf66 IgG antibodies do not correlate with the ability of sera from vaccine recipients to inhibit parasite growth in vitro nor with partial clinical protection which could be detected in some trials. Qualitative or functional parameters of SP66-induced antibody responses, such as IgG subclass composition and affinity, may be more predictive of clinical protection against malaria than quantitative estimates of antibody concentration or titre. Since these parameters are readily estimated by laboratory techniques currently available, and may be modulated by changes in vaccination protocols and by the use of different adjuvants, a better understanding of qualitative antibody responses induced by SPf66 and other asexual blood-stage malaria vaccine candidates, and of their relationship with clinical protection in vivo, is urgently needed for the improvement of currently used immunization schedules.

Influence of coronary lesions morphology on treadmill exercise stress testing after acute myocardial infarction

OBJECTIVES

To evaluate the influence of infarct related artery lesion morphology on the exercise stress test performed after a first myocardial infarction.

METHODS

We reviewed coronary angiography and the exercise stress test performed before discharge from hospital in 105 consecutive patients (91.4% male, mean age 49.6 +/- 9.2 years) with first acute myocardial infarction. Complex coronary lesions were defined by the presence of one of the following characteristics: ulcers, thrombus, shoulders, irregularities and eccentricity. According to either the existence or absence of complex coronary lesions, two groups were considered: Group I--42 patients with complex coronary lesions, and Group II--47 patients without these characteristics in coronary angiogram. Sixteen pts (14%) were excluded because the infarct related artery was occluded or existence of complex lesions in other coronary artery not related to the infarct. Left ventricular systolic function was analyzed using the "CASS score". Exercise stress test performed between the 10th and the 15th day after myocardial infarction, using Bruce protocol, were reviewed. The following parameters were analyzed: exercise time, number of metabolic equivalent units (METS), maximal heart rate attained, double product variation and number of patients with significant ST segment depression and/or angina.

RESULTS

No statistically significant differences between the two groups were obtained as far as age, sex, left ventricular function, number of diseased vessels and lesions severity. From the analysis of ergometric parameters we did not find any difference between the two groups of patients about exercise time (Group A--8.37 +/- 2.6 versus (vs) Group B 8.38 +/- 3.18), METS (Group A--8.22 +/- 2.87 vs Group B--8.13 +/- 2.97), maximal heart rate (Group A--88.2% vs Group B--87.5%) and double product variation (Group A--14547 +/- 5492 vs Group B--14553 +/- 5387). However, the number of ischemic response (defined by usual criteria of St-segment depression and/or angina) was significantly greater in patients with complex coronary lesions (ST--segment depression: Group A--26 pts vs Group B--19 pts, p < 0.05/Angina: Group A--16 pts vs Group B--4 pts, p < 0.001). Thus, complex coronary lesions are related to a high incidence of residual ischemic phenomena detected by electrocardiographic exercise stress test performed on predischarge period of acute myocardial infarction. Further studies will be necessary to show the prognostic value of particular angiographic characteristics found in coronary plaques.

[Prenatal diagnosis of congenital cardiomyopathies. Current reality in the south of the country]

In order to make an actual perspective about prenatal diagnosis of congenital heart disease in the area of influence of our department, a prospective study including 948 fetus and 185 newborn was done, 348 fetus and 20 newborn evaluated during 1993 (group I) and the remaining during 1994 (group II). In both groups indications for fetal echocardiography were mainly maternal (18%) and familiar (14%) factors, but occurrence of CHD were respectively 2% and 0% for them. Fetal factors for echocardiography account for 7%, namely arrhythmias (7%) and obstetric suspicion of CHD (6%), but occurrence of CHD was respectively 13% and 32% for group I and 36% and 48% for group II. In the newborn with serious CHD, risk factors could be identified in 30% in group I and 36% in group II, being respectively 15% and 7% referred for fetal echocardiography. It is concluded that although a rise in the number of fetus evaluated and a better obstetric accuracy have occurred, the rate of prenatal diagnosis of CHD is still very low, pointing to necessity of continuing our actual policy of teaching and spreading this area, specially in the primary health care units.

Atrioventricular valve repair using externally adjustable flexible rings

Initial results obtained with a new flexible ring, adjustable from outside of the heart after interruption of extracorporeal circulation, are presented. Twenty-five rings have been inserted in 20 patients, 14 in the mitral position and 11 in the tricuspid position. In 8 of the 14 patients receiving mitral annuloplasty, other standard mitral valve repair techniques were used. Adjustment, assisted by intraoperative transesophageal color Doppler echocardiography, was done for 10 (71%) of the mitral rings and for 8 (73%) of the tricuspid rings. Residual mitral regurgitation disappeared or became minimal in 9 (90%) patients, and a mild regurgitation remained in 1. In all patients who received tricuspid rings regurgitation was abolished after the adjustment. There was no hospital or late mortality. After a maximum follow-up of 6 months results are comparable in the tricuspid and mitral positions and echocardiographic evaluation revealed stable competent valves in all patients but one, who underwent reoperation because of failure of a mitral valve chordae shortening procedure. The use of externally adjustable rings for the mitral and tricuspid valves is a safe alternative for atrioventricular valve annuloplasty and has the additional advantage of reducing postrepair regurgitation.

Determination of arsenic, cadmium and lead in porcine and bovine kidneys by electrothermal atomic absorption spectrometry

This paper describes an ETAAS method to quantify residues of arsenic, cadmium and lead in porcine and bovine kidneys. The results of a survey conducted during 1993 are tabulated. Analysis was performed by ETAAS with a stabilized-temperature platform furnace. The determinations were performed in the linear ranges 0.5-150, 0.04-2.0 and 1.1-75 micrograms l-1 for As, Cd and Pb, respectively, in the acid digests which were obtained under controlled conditions of temperature in a tetrafluoroethylene apparatus after appropriate dilution and addition of a suitable chemical modifier. Extensive quality assurance of the methods was performed by the standard additions method and by comparison with a certified reference material. The precision was better than 9.9, 8.5 and 9.2% for As, Cd and Pb, respectively. Low relative standard deviations of 7.4, 7.0, and 2.8% for As, Cd and Pb, respectively, were obtained by comparing the levels found in the kidney reference material and the certified values, showing this method to be satisfactory and suitable for routine analysis. The mean levels of As, Cd and Pb in porcine kidney were 2.11 (1.11-5.49), 0.81 (0.02-4.22) and 0.18 (0.02-0.42) microgram g-1 respectively. Those in the adult bovine kidney were 1.77 (0.42-3.42), 1.26 (0.01-6.16) and 0.73 (0.19-2.55) microgram g-1, respectively, and in the young bovine kidney they were 1.33 (0.61-2.56), 0.49 (0.15-1.82) and 0.20 (0.12-0.29) microgram g-1.

Dose-dependent lesions of the dopaminergic nigrostriatal pathway induced by intrastriatal injection of 6-hydroxydopamine

Animal models with partial lesions of the dopaminergic nigrostriatal pathway may be useful for developing neuroprotective and neurotrophic therapies for Parkinson's disease. To develop such a model, different doses of 6-hydroxydopamine (0.0, 0.625, 1.25, 2.5 and 5.0 micrograms/microliters in 3.5 microliters of saline) were unilaterally injected into the striatum of rats. Animals that received 1.25 to 5.0 micrograms/microliters 6-hydroxydopamine displayed dose-dependent amphetamine and apomorphine-induced circling. 6-Hydroxydopamine also caused dose-dependent reductions in [3H]mazindol-labeled dopamine uptake sites in the lesioned striatum and ipsilateral substantia nigra pars compacta (up to 93% versus contralateral binding), with smaller losses in the nucleus accumbens, olfactory tubercle and ventral tegmental area. In the substantia nigra pars compacta and the ventral tegmental area, the number of Nissl-stained neurons decreases in parallel with the reduction in [3H]mazindol binding. The reduction in [3H]mazindol binding in the striatum and the nucleus accumbens, and the reduction in [3H]mazindol binding and in the number of Nissl-stained neurons in the substantia nigra pars compacta and the ventral tegmental area is stable for up to 12 weeks after the lesion. Macroscopically, forebrain coronal sections showed normal morphology, except for rats receiving 5.0 micrograms/microliters 6-hydroxydopamine in which striatal cross-sectional area was reduced, suggesting that this high dose non-specifically damages intrinsic striatal neurons. Nissl-stained sections revealed an area of neuronal loss and intense gliosis centered around the needle track, which increased in size with the dose of neurotoxin. Striatal [3H]sulpiride binding was increased by 2.5 micrograms/microliters and 5.0 micrograms/microliters 6-hydroxydopamine, suggesting up-regulation of dopamine D2 receptors. Striatal binding of [3H]CGS 21680-labeled adenosine A2a receptors, but not of [3H]SCH 23390-labeled dopamine D1 receptors, was reduced at the highest dose, suggesting preservation of the striatal intrinsic neurons with the lower doses. This study indicates that intrastriatal injection of different doses of 6-hydroxydopamine can be used to cause increasing amounts of dopamine denervation, which could model Parkinson's disease of varying degrees of severity. Injecting 3.5 microliters of 2.5 micrograms/microliters 6-hydroxydopamine appears to be particularly useful as a general model of early Parkinson's disease, since it induces a lesion characterized by robust drug-induced rotation, changes in binding consistent with approximately 70% dopamine denervation, approximately 19% dopamine D22 receptor up-regulation, negligible intrinsic striatal damage and stability for at least 12 weeks. This study outlines a technique for inducing partial lesions of the nigrostriatal dopamine pathway in rats.(ABSTRACT TRUNCATED AT 400 WORDS)

[Coronary artery dissection without acute myocardial infarction]

A 57 year-old-man with acute aortic dissection (DeBakey type I) who developed right coronary artery dissection without acute myocardial infarction. He was successful surgically treated and became asymptomatic.

Tumor markers in serum, polyamines and modified nucleosides in urine, and cytogenetic aberrations in lymphocytes of workers exposed to polycyclic aromatic hydrocarbons

Some polycyclic aromatic hydrocarbons (PAHs) such as benzo(a)pyrene and benzo(a)anthracene are well-established genotoxic agents. Long-term exposure to PAHs may lead to proliferative cell disorders in humans, predominantly in the skin, lung, and bladder. The concentration of several tumor markers in serum, of polyamines and modified nucleosides in urine, and of cytogenetic endpoints in peripheral lymphocytes (sister-chromatid exchanges, high frequency cells [HFC], and micronuclei) were measured in 149 male workers exposed to PAHs in two coke oven and one graphite electrode plants, and in 137 controls. We have assessed whether these biomarkers were related to several parameters reflecting exposure to PAHs, i.e., the sum of the airborne concentration of 13 PAHs, 1-hydroxypyrene (1-OHP) concentration in postshift urine, benzo(a)pyrene-diolepoxide adducts to hemoglobin (BPDE-Hb adducts), and duration of exposure, taking also into account several possible confounding factors. HFC was the biomarker most consistently associated with the intensity of current exposure to PAHs. Smoking exerts an independent effect on the same parameter. On the basis of the logistic regression between the prevalence of abnormal HFC values and PAHs in air and 1-OHP in postshift urine found in nonsmokers, it is suggested that the latter should be kept below 6.4 micrograms/m3 and 2.7 micrograms/g creatinine, respectively. No relationship was found between the cytogenetic effects and BPDE-Hb adducts although both parameters are statistically correlated with the airborne PAH level. Some tumor markers in serum (carcinoembryonic antigen, tissue polypeptide antigen, sialic acid) and the urinary concentration of some polyamines were correlated with either PAHs in air or 1-OHP in urine. The associations, however, were very weak which suggests that these biomarkers have limited practical value for the health surveillance of groups of workers exposed to genotoxic PAHs.

[Myocardial revascularization in left coronary trunk lesion in patients over 65 years old]

PURPOSE

To study the short and long-term follow-up of patients with left main coronary artery disease (LMCAD) and age over 65 years, by comparing the results with patients under 65 years-old.

METHODS

Twenty-two patients with LMCAD and mean age of 69 +/- 3.5 years (group I) were underwent isolated coronary artery bypass grafting (CABG) and compared to 31 patients with LMCAD, mean age of 54 +/- 7 years (group II), who also underwent isolated CABG. The life-table Kaplan-Meyer method was used to estimate the post-operative survival. The chi-square and Student "t" test were used when necessary.

RESULTS

Despite higher operative mortality in group I (9.1% x 3.2%), the difference was statistically not significant. The operative morbidity was similar in both groups. Actuarial survival at 4 years was 85% in group I and 95% in group II. Actuarial survival free of cardiac events was 69% in group II and 75% in group II.

CONCLUSION

The CABG is well tolerated and had low morbidity and acceptable mortality in old patients with LMCAD. The long-term survival in these patients was very similar to the younger patients.

[Diagnosis of coronary disease using echocardiography with inotropic dobutamine stimulation]

PURPOSE

To evaluate dobutamine echocardiography capacity to diagnose coronary artery disease.

STUDY DESIGN

Prospective clinical study.

SETTING

Cardiology Department of Hospital Santa Marta.

PATIENTS

32 patients with suspected coronary artery disease, without myocardial infarction, have been studied.

METHODS

An intravenous perfusion of dobutamine with gradual doses, from 5 to 40 micrograms/kg/min, and increments of 5 to 10 micrograms/kg/min, in 3 minute stages, except the last stage which lasted only 1 minute with 40 micrograms/kg, was performed. Twelve-lead ECG were registered to detect ST changes and symptoms, namely chest pain. Basal and dobutamine bidimensional echocardiograms, in the end of each stage and during recovery, were registered in video. The segmental analysis was performed considering the left ventricle divided in 16 segments. It was considered positive the occurrence or aggravation of the contractility asynergy of the left ventricle with inotropic stress. All the patients were submitted to coronary arteriography.

RESULTS

Due to the bad quality of the echocardiographic images 2 patients were excluded. The stress dobutamine echocardiograms were positive in 14 P and negative in 16 P. The coronary arteriography showed coronary disease in 18 cases and absence of significant lesions in 12 cases. The values for sensitivity, specificity positive predictive value and negative predictive value obtained with dobutamine echocardiography were, 78% and 100% and 75% respectively. In Dobutamine-ECG, 7P had ST segment changes, 2 of them with chest pain values for sensitivity, specificity, positive and negative predictive value with dobutamine-ECG were, 39%, 100% and 52%, respectively. The occurrence of side-effects was observed in 8 P (27%): ventricular tachycardia (2 P-7%), complex ventricular ectopy (4 P-13%), chest pain (2 P-7%), headache (1 P-3%), nausea (1 P-3%) and palpitations (2 P-7%). There was no significant difference in the occurrence of side-effects in the two groups of patients, with and without coronary artery disease (33% vs 17%, respectively; p = ns). The reasons for early discontinuation of dobutamine infusion were: ventricular tachycardia (2 P), complex ventricular ectopy (2 P) and chest pain (1 P). Heart rate, systolic blood pressure and double-product did not differ significantly in patients with and without coronary artery disease. In dobutamine electrocardiography 7 P had ST segment changes, 2 of them with chest pain.

CONCLUSION

Dobutamine echocardiography showed in this study elevated values for sensitivity and specificity, however sensitivity can be increased with better technical conditions.

[Fetal arrhythmia. A case load of 4 years and a half]

In a 4 1/2 year period fetal, echocardiographic studies were performed on 1600 fetuses. In 55 with arrhythmia, 44 had supraventricular ectopic beats, resolved in all, and none had heart disease. Sustained arrhythmias occurred in 11 fetuses. Atrial flutter was present in 3 all with heart disease (Ebstein disease, right atrial tumour and WPW diagnosed after birth). Another 3 fetuses had supraventricular tachycardia (SVT), all with a normal heart. In the bradycardia group, 2 had complete heart block (CHB) associated with AVSD; 2 sinus bradycardia and one had non conducted atrial ectopic beats. Digoxin was the first choice drug for tachyarrhythmia therapy; association with Verapamil, Flecainide, Quinidine and Procainamide was used in 4 of the 6. One fetus with CHB received Orciprenaline with no results. Atrial flutter resolved or improved; in SVT 2 fetuses converted to sinus rhythm and one died in utero. All fetuses with CHB died in cardiac failure. Mortality was 27% (3 cases) in utero and global 36%. In our experience most fetal arrhythmias (90%) were transitory ectopic beats or non lasting bradycardia in normal heart and did not trigger other kinds of arrhythmias. In sustained arrhythmias, heart failure and heart disease had a negative effect on prognosis.

Molecular cloning and analysis of CDC28 and cyclin homologues from the human fungal pathogen Candida albicans

In the budding yeast Saccharomyces cerevisiae, progress of the cell cycle beyond the major control point in G1 phase, termed START, requires activation of the evolutionarily conserved Cdc28 protein kinase by direct association with G1 cyclins. We have used a conditional lethal mutation in CDC28 of S. cerevisiae to clone a functional homologue from the human fungal pathogen Candida albicans. The protein sequence, deduced from the nucleotide sequence, is 79% identical to that of S. cerevisiae Cdc28 and as such is the most closely related protein yet identified. We have also isolated from C. albicans two genes encoding putative G1 cyclins, by their ability to rescue a conditional G1 cyclin defect in S. cerevisiae; one of these genes encodes a protein of 697 amino acids and is identical to the product of the previously described CCN1 gene. The second gene codes for a protein of 465 residues, which has significant homology to S. cerevisiae Cln3. These data suggest that the events and regulatory mechanisms operating at START are highly conserved between these two organisms.

[Contribution to the prenatal diagnosis of congenital cardiopathies]

After concluding a local teaching program to obstetric echographists about prenatal diagnosis of congenital heart disease (CHD), we compared 2 periods of activity in fetal echocardiography, that before, lasting 3 and one half years (G.I) and the other 6 months after (G.II). During the second period 20 newborn consecutively admitted with CHD (G.III) were also studied. Teaching program protocol for the 10 district hospitals visited is described. The results show a rise from 25 to 58 foetus per month observed, comparing the two periods, being 4 and 7% respectively those referred with suspicion of CHD, and 54 and 33% the obstetric accuracy. Total incidence of CHD was 4,2%, 41 in G.I and 6 in G.II. Types of CHD, treatment and evolution are described, being the mortality 68 and 50% respectively. Of the 20 newborn from G.III, 90% had no prenatal diagnosis of CHD, being 30% high risk pregnancies. Mortality in this group was 20%, 50% in the newborn from high risk pregnancies; eight newborns were operated on without mortality, 5 to aortic coarctation and 2 with arterial switch for transposition. It is concluded the necessity of continuing teaching programs so that prenatal diagnosis of CHD may improve and the care of the newborn may so be anticipated and ameliorated.

Difficulties in the management of a parathyroid carcinoma - case-report

The case of a parathyroid carcinoma in a 61-year-old woman is described. The patient was referred to our hospital, with the diagnosis of medullary thyroid carcinoma, after a prior thyroidectomy performed at another hospital. On admission, serum calcium was 3.92 mmol/l (n.r. 2.2-2.5), PTH level was 320 ng/l (n.r. 10-65), urinary cAMP was 508.9 mmol/mmol creatinine (n.r. 330- 630) and serum calcitonin was 2.1 ng/l (n.r.<10). The patient was then submitted to a complete neck exploration and multiple nodules were removed. Histopathological diagnosis of parathyroid carcinoma was made by local recurrence and retrospectively upon closer examination of the original specimen. After surgery, normocalcemia was achieved and maintained for about four months. Serum PTH decreased to 28.8 ng/l after surgery but increased quickly to 75.6 ng/l ten days later. Three months later, there was both biochemical and clinical evidence of disease. In the following eight months, calcium levels ranged from 2.99 mmol/l to 4-24 mmol/l and PTH from 135 ng/l to 1431 ng/l. However no distant metastases were found. To Control hypercalcemia, the patient was treated with bisphosphonates but normocalcemia was never achieved. A slight and transient reduction in serum calcium as response to an acute administration of octreotide, made us not to consider this eventual modality of therapy. Sonographically guided percutaneous injection of ethanol was performed but the treatment was not found to be effective. Finally, the use of chemotherapy with 5-fluorouracil, cyclophosphamide and dacarbazine was also unsuccessful. The patient died two years after the initial diagnosis.

Differences in nigral neuron number and sensitivity to 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine in C57/bl and CD-1 mice

The present study demonstrates that the neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) causes significantly greater reductions in striatal dopamine levels in C57/bl mice than in CD-1 mice, thus confirming a greater sensitivity of the C57/bl mice to MPTP. To determine the possible reasons for this difference in MPTP sensitivity between these two mouse strains, we have compared both the organization and the number of substantia nigra (SN) neurons, the primary target of MPTP, in C57/bl and in CD-1 mice using immunostaining for tyrosine hydroxylase (TH) and calbindin-D28k (calbindin). In saline-injected animals, there is a significantly lower number of SN TH-positive and calbindin-positive neurons in C57/bl than CD-1 mice; no significant differences in the numbers of these neurons are found in the ventral tegmental area between the two strains. In MPTP-injected animals, the reductions in SN TH-positive neurons are significantly greater in C57/bl than in CD-1 mice. In contrast, MPTP does not cause any significant changes in the numbers of SN calbindin-positive neurons in either strain. The present study shows that C57/bl mice which have fewer SN TH-positive neurons are more sensitive to MPTP-induced toxicity than CD-1 mice. This observation suggests a possible inverse relationship between SN TH-positive neuron number and MPTP sensitivity. If correct, this hypothesis may be of major importance for Parkinson's disease since it is suggested that individuals at risk of developing this neurodegenerative disorder may have lower numbers of SN TH-positive neurons to start with. The present study also shows that SN calbindin-positive neurons are spared following MPTP administration. However, the observed difference in SN calbindin-positive neuron numbers does not account for the differential sensitivity to MPTP between these two mouse strains.

Determinants of urinary thioethers, D-glucaric acid and mutagenicity after exposure to polycyclic aromatic hydrocarbons assessed by air monitoring and measurement of 1-hydroxypyrene in urine: a cross-sectional study in workers of coke and graphite-electrode-producing plants

A cross-sectional epidemiological study was performed on 286 workers from two coke oven and one graphite electrode plants. The aim was to evaluate the usefulness of monitoring 1-hydroxypyrene (1-HOP) in urine for assessing exposure to polycyclic aromatic hydrocarbons (PAHs), and that of the urinary excretion of thioethers and D-glucaric acid, and the mutagenic activity of urine as indicators or biological effects of PAHs. The results confirm that 1-HOP determination in urine probably reflects exposure to PAHs by all routes and is not significantly influenced by the smoking habit. In comparison with the total PAHs in the air and 1-hydroxypyrene in urine, taken as reference exposure parameters, the results indicate that urinary D-glucaric acid excretion is not positively influenced by PAHs exposure; thioethers determination in urine is of poor value, since the smoking habit is a strong confounding factor. The determination of urinary mutagenicity might contribute to the detection of groups of workers exposed to potentially genotoxic PAHs.

Bioavailability of residues of diazepam and its metabolites

The present study was performed to determine the metabolic fate of the residues of diazepam and its metabolites in an in vivo model and using two different animal species, guinea pigs and rats, successively. Guinea pigs were orally dosed with diazepam at 100 mg/kg bw and 10 mg/kg bw. After 2 h the animals were sacrificed and their livers were removed. Rats were fed these livers and sacrificed 8 h later after having ingested the portion given. Blood, kidney, and liver of rats were collected to quantify drug residues. Oxazepam and demethyldiazepam were identified by HPLC-UV in liver and kidney rat extracts and also in some blood samples. Temazepam was only found in liver from rats that had eaten guinea pig liver dosed at the highest level. The identity of demethyldiazepam was confirmed in rat liver extracts by GC-MS. This study demonstrates the bioavailability of diazepam metabolites in a second animal (rat simulating a consumer) following a diazepam administration to a first animal (guinea pigs simulating a target animal). Residue concentrations were reduced from 9.7 and 243 micrograms in consumed guinea pig liver to 3.75 and 455 ng/g in rat liver for parent drug and oxazepam, the lowest and highest residues found, respectively.

Immediate pars plana vitrectomy in the management of inadvertent intracameral injection of gentamicin. A rabbit experimental model

PURPOSE

Acute retinal toxicity secondary to inadvertent intracameral injection of massive doses of gentamicin is a devastating complication of cataract surgery, for which no treatment, to date, either surgical or medical, has been shown to be effective. A rabbit experimental model was used to examine the effect of immediate pars plana vitrectomy in the management of inadvertent intracameral injection of gentamicin.

METHODS

Twenty-seven rabbit eyes were subjected to lensectomy with or without preservation of the lens capsule. Aphakic rabbit eyes and rabbit eyes with an intact lens capsule were then subjected to injections of massive doses (4 mg and 20 mg) of gentamicin into the anterior chamber. Experimental eyes underwent an immediate pars plana vitrectomy and posterior segment lavage. The rabbits were killed after 7 days. Light microscopic examination was then performed to ascertain the degree of retinal damage caused by the injection.

RESULTS

Rabbit eyes receiving immediate pars plana vitrectomy exhibited far less structural damage to the retina, as seen by light microscopy, than did corresponding control eyes. Furthermore, there appeared to be a protective effect of an intact lens capsule with regard to retinal damage.

CONCLUSIONS

Immediate pars plana vitrectomy and posterior segment lavage may alleviate the effects of intracameral injection of gentamicin. This preliminary study demonstrates the need to perform further studies with a vascularized primate retina to evaluate immediate pars plana vitrectomy in the management of inadvertent intracameral injection of gentamicin.

[Fetal cardiology. Bases for the prenatal diagnosis of congenital cardiopathies]

The bases for prenatal diagnosis of congenital heart disease are presented, in the line of a comprehensive program undertaken by paediatric cardiology and obstetrics. This program is designed to improve the screening of fetal heart diseases by obstetric echographists, particularly those working at peripheral high risk clinics. It includes the visit of paediatric cardiologists to district hospitals for joint meetings with local physicians, going over theoretical aspects, case presentation and four chamber view with outflow tract demonstrations using local ultrasound equipment. Referring protocols, handouts and support media exchange are contemplated. Support texts on the program divulged, on etiology of congenital heart disease, on abnormal fetal echocardiography and on fetal dysrhythmias are presented here in. The need for an organized national effort to increase the prenatal diagnosis of congenital heart disease is emphasized as well as the need to centralize some aspects related to diagnosis and treatment in order to improve the care of newborns with congenital heart disease.

Chronic levodopa administration alters cerebral mitochondrial respiratory chain activity

Parkinson's disease (PD) is characterized mainly by a loss of nigrostriatal dopamine neurons. Thus far, the actual physiopathology of PD remains uncertain, although recent studies have found decreased activity of complex I, one of the enzymatic units of the mitochondrial respiratory chain, in various tissues of PD patients. Because most, if not all, of PD patients are treated chronically with levodopa, the precursor of dopamine, and because we have shown previously that catecholamines may alter mitochondrial respiration, we assessed the effects of chronic administration of levodopa on complex I activity in rat brain. We found that chronic administration of levodopa, at a dose used in PD patients, caused a significant reduction in complex I activity while it did not affect the activities of complex II, complex IV, and citrate synthase. Reduction in complex I activity correlated well with catecholamine innervation as the reduction was observed mainly in the striatum and substantia nigra and to a lesser extent in the frontal cortex but not in the cerebellum. Moreover, the levodopa-induced decrease of complex I activity was reversible since activities at 1, 3, and 7 days after the last injection showed a progressive return to control values. Incubation of whole brain mitochondria in vitro showed that both levodopa and dopamine inhibit complex I activity in a dose- and time-dependent manner. In contrast, other compounds such as homovanillic acid, 3,4-dihydroxyphenylacetic acid, and 3-O-methyl-dopa were minimally effective. Reduced glutathione, ascorbate, superoxide dismutase, and catalase prevented the effect of levodopa and dopamine on complex I. Various inhibitors of monoamine oxidase also prevented the effect of dopamine.(ABSTRACT TRUNCATED AT 250 WORDS)

[Fetal echocardiography. The results of a 3-year study]

During the last three years (July 89 to July 92), 875 fetal echocardiographic studies were performed, at a mean gestational age of 26 +/- 6.5 weeks (12 to 40 weeks), with the following main referral indications: family history of congenital heart disease 23%; advanced maternal age 13%; fetal arrhythmia 10%; amniotic fluid abnormalities 8%; fetal malformations 7%; diabetes 6%; four chamber view changes 4%. There were 15 twin pregnancies, two of them thoracopagus. The referral patterns with higher percentage of cardiac pathology were: abnormal four chamber view 56%; fetal chromosomal anomalies 50%; omphalocele 33%; twin pregnancy 33%; IUGR 29%; arrhythmias 20%. The referral patterns with lower percentage of cardiac pathology were: congenital heart disease in the family 0.2%; maternal risk 2%; amniotic fluid volume alterations 2%. The diagnosis of congenital heart disease was made in 37 fetus (4.2%), with the following most frequent: 9 cases with the atrioventricular septal defect, 5 cases with ventricular septal defect, 5 cases with hypoplastic left heart syndrome and 5 cases with tricuspid valve abnormalities. From a total of 78 referred fetal arrhythmias, 25 were confirmed, 20 being ectopic beats without structural heart disease, 3 with tachycardia, and 2 with bradycardia. One newborn with tachycardia and Ebstein's disease died, and the fetus with AV block and left atrial isomerism died in utero. The treatment and follow up of the remaining cases with heart disease are described. The whole mortality in the cases with heart pathology was 65%.(ABSTRACT TRUNCATED AT 250 WORDS)

[Clear cell hepatocellular carcinoma]

A case of a 62 year old white patient with mild dyspeptic symptoms and nodular hepatomegaly is presented. The histologic examination of a liver biopsy revealed a hepatocellular carcinoma clear cell variant. There were no signs of chronic hepatic failure. The disease showed an indolent clinical behaviour, thus the beginning of chemotherapy was delayed until clinical deterioration was obvious. Clinical improvement was obtained with adriamycin. A review of the literature on this rare histologic variant of hepatocellular carcinoma is made.

Adenosine receptor antagonists potentiate dopamine receptor agonist-induced rotational behavior in 6-hydroxydopamine-lesioned rats

Adenosine receptor antagonists, DMPX, PACPX and theophylline, produce contralateral rotations in unilateral 6-hydroxydopamine-lesioned rats. DMPX and theophylline markedly increase rotations produced by bromocriptine (a dopamine D2 receptor agonist) and/or SKF38393A (a dopamine D1 receptor agonist). All of these effects are inhibited by CGS21680C (an adenosine A2 receptor agonist). These findings suggest synergistic interactions among D1, D2 and A2 receptors that may be relevant to the treatment of Parkinson's disease.

[Functional assessment of the autonomic nervous system in rheumatoid arthritis]

Sympathetic and parasympathetic nervous system evaluation was performed in 21 patients with rheumatoid arthritis. Every patient had autonomic nervous system (ANS) dysfunction, the parasympathetic involvement being the most frequent. ANS dysfunction may explain some manifestations and may well be the expression of a larger neuropathic involvement with pathogenic implications.

Endomysial antibody: is it the best screening test for coeliac disease?

The sensitivities and specificities of the IgA and IgG antigliadin antibody and the IgA antireticulin antibody have been compared with the recently described endomysial antibody directed against the basement membrane of smooth muscle in monkey oesophagus. One hundred and seventeen patients with adult coeliac disease (21 untreated), 84 patients with inflammatory bowel disease, systemic lupus erythematosus and rheumatoid arthritis (comprising the disease control group), 47 normal controls and a miscellaneous group of 29 patients, who were selected because of a positive reticulin staining pattern, were investigated. These results were correlated with the degree of abnormality of the intestinal mucosa in patients with adult coeliac disease. Endomysial antibodies were found in all patients with untreated coeliac disease and subtotal villous atrophy and in 47% of patients on a non-strict gluten free diet. One patient on a strict gluten free diet was positive and had partial villous atrophy while all patients in disease control groups were negative. Results were variable with the antireticulin and antigliadin antibodies. Sensitivity and correlation with subtotal villous atrophy in the untreated patients was 100%. It is concluded that the endomysial antibody is superior to other current antibody tests and should be used in preference for the diagnosis of coeliac disease.

Functional significance of premature ventricular complex morphology evaluated during treadmill exercise stress test in patients with coronary artery disease

OBJECTIVES

To evaluate the relation between premature ventricular complexes morphology and left ventricular myocardial systolic function in patients with proved coronary artery disease.

SETTING

Department of Cardiology at General Hospital.

METHODS

From 112 patients (pts) with proved coronary artery disease, thirty-three pts with premature ventricular complexes (PVC) detected during treadmill exercise stress test were selected. Two groups of pts were considered: group I-20 pts with regular contour or with a narrow notching (< 40 ms; type I PVC) and group II-13 patients with wide notching (> 40 ms; type II PVC). In each group the following parameters were studied: ejection fraction, QRS duration, duration of exercise, number of metabolic units and the prevalence of ventricular aneurysm and mitral regurgitation.

RESULTS

Statistical significant differences were found between group I and II concerning the mean ejection fraction (59.2% vs 48.6%; p < 0.05). The prevalence of ventricular aneurysm and mitral regurgitation was higher in patients with type II ventricular premature complexes (10% vs 30%).

CONCLUSION

Particular characteristics of premature ventricular complexes detected during treadmill exercise stress test, in patients with proved coronary artery disease, suggest the presence of left ventricular myocardial systolic dysfunction.

[Enalapril and myocardial protection from stress by cold]

PURPOSE

To evaluate the myocardial protective effect of enalaprilat in rats submitted to stress by cold.

METHODS

Fifteen adults, male rats were studied. They were allocated into four groups: group A received unrestricted diet + intraperitoneal (IP) diluent; group B: unrestricted diet + IP enalaprilat 1.0 mg/kg; group C: high salt diet (HD) for seven days + IP indomethacin 1.0 mg/kg and group D received high salt diet for seven days + IP indomethacin 1.0 mg/kg + IP enalaprilat 1.0 mg/kg. Three animals were the control group. The animals of the groups A, B, C and D were then submitted to stress by cold. Fragments of the left ventricle were obtained for electron microscopy and the occurrence of mitochondrial lysis or preservation of the mitochondrial ultrastructure were considered as parameter for myocardial protective effect evaluation.

RESULTS

Crystolysis (partial or total) was observed in 16.2% group A; 19.5% of group C; 3.2% of group B and in 8.8% of group D.

CONCLUSION

Enalaprilat protects the cardiomyocyte from the stress by cold.

Composite tumor of the main bile duct producing several regulatory peptides

Herein we describe what is, to our knowledge, the first reported case of a composite tumor of the main bile duct with epiploon metastases. Glucagon, pancreatic polypeptide, and somatostatin-immunoreactive cells were demonstrated in these metastases, but not serotonin, gastrin, or insulin-immunoreactive cells. The clinical significance of the neuroendocrine cells in the present case is discussed.

[Heart surgery without previous heart catheterization, in pediatric cardiology]

STUDY OBJECTIVE

To determine the influence of echocardiography in the preoperative diagnosis of heart diseases in children.

DESIGN

Retrospective study.

SETTING

Hospitalized children admitted in Departments of Pediatric Cardiology and Cardiothoracic Surgery.

PATIENTS

Children of both sexes, aged from neonate to 14 years old, with heart disease who underwent cardiac surgery.

MATERIAL AND METHODS

From January 1989 to July 1990, 220 consecutive cardiac surgeries were performed in children with heart disease. The initial diagnosis was based on data from clinical examination, electrocardiogram, thorax X-Ray and echocardiogram (M-mode, 2D, conventional and colour Doppler). Patients were separated in three groups according to their ages: newborn infants less than 28 days old; infants less than 12 months old; children more than 1 year old and less than 14 years old. Patients were separated according to the investigations used further for preoperative diagnosis: whether they had or not cardiac catheterization performed prior to surgery.

RESULTS

From 220 surgical interventions performed, 124 were "open heart" surgeries (9 neonates, 28 infants and 87 children) and the remaining had "closed heart" operations (14 neonates, 37 infants and 45 children). Preoperative diagnosis was mainly dependent on echocardiography, dispensing catheterization in 90 cardiac interventions. The diagnosis was confirmed at surgery or at autopsy. There were 9 deaths, 3 of which occurred in patients not submitted to cardiac catheterization.

CONCLUSIONS

Echocardiography is a reliable method for investigation and establishment of the preoperative diagnosis of heart diseases in children. Its use may further reduce the need for diagnostic catheterization in children, particularly in risk groups.

Changes in sex ratio during attempts to establish a laboratory colony of Lutzomyia longipalpis (Diptera: Psychodidae)

After the discovery of "one spot" and "two spot" male Lutzomyia longipalpis in the same dog's kennel, attempts were made to establish laboratory colonies of the two forms. Pure lines of the two forms were not obtained and various "intermediate" males were recorded. Interbreeding between the two populations probably occurs in nature but appears precarious. In one colonization attempt a change in sex ratio was noted from the 7th generation onwards and only females emerged in the 11th generation.

Mating behaviour between different lines of Lutzomyia longipalpis (Diptera: Psychodidae)

Homologous and heterologous crosses were made between laboratory-reared Lutzomyia longipalpis. One line of insects originated from Para State and the other from Minas Gerais. Homologous matings showed that the two lines behaved differently before and during coition and that a mixture of the two behaviour patterns occurred in heterologous crossings.

Plasma catecholamines and postural hypotension in familial amyloidotic polyneuropathy of the Portuguese type

Plasma adrenaline and noradrenaline levels were measured while supine and following head-up tilt to 45 degrees, in both normal controls and in patients with familial amyloidotic polyneuropathy of the Portuguese type. In nine patients systolic blood pressure fell by less than 15 mmHg, while in seven patients it fell by more than 15 mmHg. Plasma noradrenaline rose during tilt in the majority of patients, as in the controls. There was no correlation between levels of catecholamines and fall in blood pressure on head-up tilt. The data excludes widespread sympatho-neural failure as a cause for postural hypotension in familial amyloidotic polyneuropathy of the Portuguese type. The results are compatible with either segmental/patchy sympathetic denervation or dysfunction of the receptor/effector mechanisms in target organs such as the heart and blood vessels.

An alternative methodological approach for studies in family planning

"An alternative to the methodological approach traditionally used in studies on family-planning practices was developed and applied in a retrospective investigation of the decision making of a sample of women [in South Africa] regarding their adoption of contraceptive sterilization. The approach is based on the premise of an interparadigmatic overlap and makes provision for integrating analytical levels and employing a combination of quantitative and qualitative research methods in a research design.... The results of the investigation showed the respondents' perceptions of the most important reasons for their decision to be sterilized. The findings provided insight into the interdependence of the sample's fertility behaviour and societal modernism within the particular institutional and socio-cultural setting." The data are from a survey carried out in the Cape Peninsula. (SUMMARY IN AFR)

Anatomy of the buccal fat pad and its clinical significance

Interest in the anatomy of the buccal fat pad was aroused by two clinical cases where the fat pad was involved by pathology. In one, there was an extensive lipoma of the buccal fat pad which had been unsuccessfully operated on on two previous occasions. The reason for the lack of success was incomplete removal of the fat pad. In the second case, there was an arteriovenous malformation involving the fat pad which necessitated complete removal. Fresh cadaver dissections were carried out to accurately determine the anatomy. Particular attention was paid to the temporal extension, since this area is frequently disregarded.