Effect of pretreatment with anticonvulsants on theophylline-induced seizures in the rat

Seizures, often with fatal outcome, are a manifestation of pronounced theophylline toxicity. Prodromal symptoms are not always apparent, and the seizures are reported to be, in certain cases, refractory to treatment with anticonvulsant drugs. The purpose of this investigation was to examine, by an established animal model, which of the commonly used anticonvulsants can reduce the central nervous system sensitivity to theophylline neurotoxicity and what should be the preferred treatment in cases in which theophylline toxicity is anticipated. The anticonvulsant agents in doses that are found to be effective in other types of experimentally induced seizures in rats, clonazepam 5 mg/kg, diazepam 5 mg/kg, phenytoin 8 mg/kg, phenobarbital 100 mg/kg, valproic acid 150 mg/kg, and magnesium sulphate 300 mg/kg, or the vehicle (controls) were administered intravenously to Lewis female rats. Thirty minutes later, theophylline was infused at a constant rate of 1.3 mg/min until onset of maximal seizures. Theophylline concentrations in the cerebrospinal fluid, brain, and serum were assayed by a high-performance liquid chromatography method. It was found that pretreatment with either clonazepam, diazepam, phenobarbital, or valproic acid increased the central nervous system thresholds to the theophylline-induced seizures, whereas phenytoin and magnesium sulphate did not attenuate the sensitivity of the brain to the stimulatory action of this widely used bronchodilator. Therefore, whenever theophylline toxicity is suspected, treatment with either diazepam, clonazepam, phenobarbital, or valproic acid can reduce the hazard associated with theophylline-induced seizures.

[The assessment of the histomorphological characteristics of the arteria gastroepiploica dextra and its potential as an artery for myocardial revascularization]

OBJECTIVE

Comparative analysis of the histomorphological characteristics of left (LIMA) and right (RIMA) internal mammary arteries, right gastroepiploic (RGEA) and anterior descending artery (ADA) with evaluation of the respective prevalence of atherosclerotic changes.

SETTINGS

Laboratory of Anatomo-Pathology of a Central Hospital with necropsy material obtained from consecutive individuals, deceased of a non-cardiac cause and older than 60 years.

MATERIAL AND METHODS

In 31 cadaver fragments of the RIMA, LIMA, GEA and ADA, were obtain, subsequently fixed and stained in order to become evident the structure of the medial layer, and the presence of possible atherosclerotic changes (intimal Hyperplasia, cholesterol clefts, foam-cells, inflammatory cells infiltrate, rupture of the internal elastic lamina, medial fibroses and calcifications).

RESULTS

1--The RGEA has the structure of a muscular artery as the ADA, opposed to the LIMA and RIMA that are elastic arteries. 2--The atherosclerotic changes were predominantly found in the ADA with no significative differences in there prevalence in the RIMA, LIMA or RGEA.

CONCLUSIONS

The RGEA despite having histological characteristics diverse than the LIMA and RIMA, has a similar prevalence of atherosclerotic changes and intimal hyperplasia; those allow us to predict a behaviour and a long-term patency comparable, when used as bypass graft for myocardial revascularization.

[Postoperative morbidity and mortality after surgical intervention for gastric carcinoma in advanced stage]

The paper reports the authors' experience in a group of 546 patients who underwent surgical treatment for gastric cancer from 1981 to 1988. Of 437 patients (80%) with advanced gastric cancer, 121 (28%) received palliative treatment and 316 (72%) were treated for curative purposes. Postoperative care was normal in 331 patients with a mean hospital stay of 11 days; various complications occurred in 106 patients with a mean hospital stay of 26 days. Overall operative mortality was 6% (27 patients). This study aimed to assess the main factor responsible for postoperative morbidity and mortality. Findings were compared to previously reported data and were shown to be similar.

[Structural changes in pulmonary vessels and coronary arteries in hypoplastic left heart syndrome]

In order to correlate gross morphological features with pulmonary and coronary vasculature changes in hypoplastic left heart syndrome (HLHS) 15 heart-lung necropsy specimens from neonates were analysed. Histology of left atrium wall, lung vessels with pulmonary arteriolar disease morphometric grading, study of intra and extra pulmonary wall veins and coronary arteries were recorded. Classic HLHS was observed in 11, and DORV with mitral atresia in 4, the foramen ovale (FO) being the only left atrium outflow tract in all. All specimens had increased % of thickness and muscular extension of arterioles and increased wall thickness of pulmonary veins, but severer arteriolar and venous changes with left atrium fibrosis were noticed in 8 specimens with either closed FO (3 cases) or mean FO diameter (d) of 5 mm when compared with specimens with mean FOd of 9 mm. Coronary arteries histology disclosed in 4 of 8 specimens with opened but hypoplastic mitral valve, intima proliferative changes with lumen narrowing, not observed in 7 specimens with mitral valve atresia. We concluded that in HLHS closed or restrictive FO and permeable mitral valve may predispose neonates to respiratory complications, right ventricle abnormal function and arrhythmias, specially after cardiac surgery.

[Comparison of immunofluorescence, enzyme immunoassay and cell culture for the diagnosis of Chlamydia trachomatis in urogenital infections]

We evaluated the usefulness of the direct immunofluorescence test with monoclonal antibodies and the enzyme immunoassay in comparison with isolation in cell cultures for the diagnosis of Chlamydia trachomatis in 55 endocervical specimens from female prostitutes and 21 urethral specimens from men with diagnosis of nongonococcal urethritis. In comparison with culture, the enzyme immunoassay had a sensitivity of 100% and a specificity of 95%. The immunofluorescence test had a sensitivity of 92% and a specificity of 98%. The positive and negative predictive values for the enzyme immunoassay were 81% and 100% and for immunofluorescence 92% and 98% respectively. The immunologic methods appear to be satisfactory alternatives to culture for detecting C trachomatis in genital specimens in the studied populations.

[Biopsy of the right ventricle endomyocardium. Experience at the Santa Marta Hospital]

OBJECTIVE

To review the experience of Santa Marta Hospital in the right ventricle endomyocardial biopsy technique.

DESIGN

Retrospective analysis of the results, diagnostic value and complications of the myocardial biopsies performed between April/87 and March/90.

PATIENTS AND INTERVENTIONS

255 biopsies were performed; 221 on 13 patients submitted to orthotopic heart transplantation (nine male and four female, aged between 21 and 55 years old), and the remaining on 34 patients (22 male and 12 female aged between 15 and 64 years old), mainly on cardiomyopathies.

RESULTS

In 221 biopsies performed in heart transplant recipients, we found: 109 with no rejection, 21 with moderate rejection, 57 with mild rejection and only one case showed severe rejection. In this group six biopsies were considered inconclusive. In the group of patients not submitted to heart transplantation the histological findings were inespecific in the great majority of the cases. In the 255 procedures four complications were detected (1.56%), with no mortality; two hemopericardium with tamponade (0.78%), one pneumothorax and one atrial fibrillation.

CONCLUSIONS

Endomyocardial biopsy essential for histological diagnosis of acute rejection following heart transplantation has revealed to be a save procedure with a small number of complications.

[Use of mechanical staplers in colostomy]

The authors used the technique of Chung, slightly modified, to perform the end colostomy in five patients who underwent abdomino-perineal resection according to Miles for rectal carcinoma. The technique proved to be easy and quick. The results have been satisfactory, without complications such as infections, necrosis, stenosis, retraction or paracolostomy hernias.

[Validity and limitations of the CEA test in the treatment of colorectal carcinoma]

CEA appears to be a good marker in the follow up of patients operated for colorectal cancer. The Authors analyse, on the base of literature data, the results of CEA test in their experience of colorectal cancers operated from 1978 to 1987. They confirm the importance of CEA as recurrence marker, however the test, by itself, is not sufficient to always identify a new onset of the disease.

Flow cytometric analysis of DNA ploidy pattern from deparaffinized formalin-fixed gastric cancer tissue

Histologically processed tissue from gastric cancers has been analyzed by flow cytometry in an attempt to correlate DNA ploidy pattern and behavior of the tumor. Of the mucosal and submucosal cancers (so-called early, all stage I in the present series), 62.7% show a diploid DNA pattern and 37.3% show a single aneuploid pattern. Of the deeply infiltrating (beyond the submucosa) cancers (stage II and III), 52.1% are single aneuploid and 47.9% are multiploid. While stage-I patients are all alive at the end of the follow-up period (6 years), in stage II and III cases Cox's regression model shows that the hazard function depends on DNA pattern: survival is negatively influenced by multiploidy. On this basis, it may be assumed that the DNA pattern is a useful prognostic indicator of gastric cancer. As expected, in Cox's regression model an even more important negative correlation exists between survival and stage: single aneuploid cases in stage II have a better prognosis than those in stage III. Instead, no correlation is found between histological cancer subtype (Laurén and WHO classifications), grade and DNA pattern.

Field evaluation of enzyme-linked immunosorbent assay for the serodiagnosis of tuberculosis

An enzyme-linked immunosorbent assay (ELISA) was evaluated as a serodiagnostic test for active tuberculosis in La Paz, Bolivia. ELISA was compared with sputum smear in 277 persons presenting to the Instituto de Torax and was used for screening in 1,458 military personnel. The test was performed under field conditions on 4-microliter samples of capillary blood obtained by finger prick. ELISA was found to have a sensitivity of 69% and a specificity of 88%. Sputum smear had a sensitivity of 79% and a specificity of 100%. ELISA was found to have undiminished sensitivity and specificity in patients who were sputum-negative, and the two tests could be combined to achieve a sensitivity of 92% and specificity of 88%. Positive and negative predictive values were highest for populations with tuberculosis prevalences in the range of that seen among patients presenting to the Instituto de Torax in Bolivia, but ELISA also led to the diagnosis of tuberculosis in 5 of 1,458 soldiers tested in the screening program.

[Comparative aspects of Crohn disease and ulcerative hemorrhagic rectocolitis]

The Authors report the comparative study on 42 patients with ulcerative haemorrhagic colitis and 33 patients with Crohn's disease observed in surgical pathology department of the University of Siena from 1970 to 1978. They have compared aetiology, pathogenesis, laboratory dates, pathologic and endoscopic findings, to conclude the absence of any correlation between them.

The immune spectrum in patients with pulmonary tuberculosis

The immune response to mycobacterial antigens of 65 patients with pulmonary tuberculosis was studied using delayed skin test reactions and enzyme-linked immunosorbent antibody assays. Evidence for a spectrum of immune response was found. Six of 35 patients studied during the first month of therapy had tuberculin skin test anergy. Anergy was not related to state of nutrition or extent of disease, but it may have been associated with radiographically acute disease. The 6 anergic patients had somewhat higher antibody titers to mycobacterial protein, but not polysaccharide antigens, than did nonanergic patients.

Myosin synthesis increased by electrical stimulation of skeletal muscle cell cultures

When cultures of skeletal muscle cells of the chick embryo are subjected to repetitive, electrical stimulation, the contractions increase the amount of protein produced by these cells. The increase is greater for contractile proteins such as myosin heavy chain than for total cellular protein. This demonstrates that in a culture system of skeletal muscle cells that have differentiated in the absence of innervation, one can elicit the protein synthetic response associated with skeletal muscle hypertrophy in vivo.