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J A de Oliveira

Publications and source records attributed to J A de Oliveira.

At least 19 recordsLinked to original sources
PubMed1999

Hair cell loss and regeneration in the chick cochlea after treatment with gentamicin.

Hair cells can be damaged by countless agents, among them aminoglycoside antibiotics. In the chick cochlea, the hair cell loss can be recovered by regeneration. The objectives of the present investigation were to study the time progression of injury caused by gentamicin and the regeneration process in chick hair cells. Gentamicin was administered in a single subcutaneous dose of 125 or 250 mg/kg to two groups of 3-day old chicks. The cochleae were processed for analysis by scanning electron microscopy on the 1st, 3rd, 5th and 20th day after injection. The cellular sequence of degeneration and regeneration was studied. On the 20th day, most it he damaged cochlear area showed regenerated hair and support cells. Stereocilia and microvilli were observed on the apical surface of the regenerated hair cells.

Animals↗
PubMed1997

Myocardial ventricular mass related to coronary artery distribution in human hearts.

This prospective study of 120 autopsy collected human hearts correlates the "Right Ventricle/Left Ventricle" free walls mass ratio and the ventricular mass fraction supplied by the right coronary ("Right Coronary/Ventricular Weight"). Different coloured gel injected through both coronary artery's capillary beds allowed ventricular myocardium separation to obtain the weights. In hearts without hypertrophy, mean +/- standard deviation of the "Right Ventricle/Left Ventricle" mass ratio was 0.54 +/- 0.09 for males and 0.62 +/- 0.23 for females; "Right Coronary/Ventricular Weight" mass ratios were 0.39 +/- 0.08 and 0.39 +/- 0.04, respectively. Mean +/- standard deviation of the "Right Ventricle/Left Ventricle" and "Right Coronary/Ventricular Weight" ratios were 0.37 +/- 0.05 and 0.36 +/- 0.10, respectively in hearts with "Left Ventricle Hypertrophy"; 0.56 +/- 0.07 and 0.38 +/- 0.11 in hearts "Without Hypertrophy"; 0.54 +/- 0.08 and 0.39 +/- 0.08 in hearts with "Biventricular Hypertrophy"; 0.89 +/- 0.16 and 0.49 +/- 0.06 in hearts with "Right Ventricle Hypertrophy". Means and variances are narrower for the "Right Coronary/Ventricular Weight" than that observed for the "Right Ventricle/Left Ventricle" mass ratio. It is due to the special double coronary arrangement in which every artery irrigates both ventricles. These results suggest that the usual pattern of the human coronary arteries' anatomy acts as a buffer for the ventricular mass distribution to be irrigated by both arteries in hypertrophy.

Adolescent↗
PubMed1997

Typical and atypical lung carcinoids: clinical and morphological diagnosis.

Forty cases of carcinoid tumors of the lung were studied retrospectively from 1989-1993 in the Pathology Department of Hospital Pulido Valente in Lisbon. The mean age of patients was 44 years old, and the presenting symptoms included hemoptysis, cough, thoracic pain, fever, and dyspnea. An endobronchial mass was seen in 75% of the cases. The histopathological study was based on the following morphological criteria: disorganized architecture with increased cellularity (8 cases; 20%), nuclear pleomorphism (14 cases; 22%), the presence of coarse chromatin (19 cases; 30%), increased mitotic activity (13 cases; 21%), enlarged nucleoli (17 cases; 27%), necrosis (12 cases; 25%), vascular permeation (8 cases; 15%), distant metastasis (6 cases; 14%). Chromogranin was the most strongly reliable immunostaining for the diagnosis. In our series the initial routine diagnosis and the diagnosis after morphological criteria evaluation matched, and in 14 cases the final diagnosis was of atypical carcinoids.

Adolescent↗
PubMed1997

Middle turbinate headache syndrome.

The middle turbinate and nasal septum are innervated by the anterior ethmoidal nerve, a branch of the ophthalmic division of the trigeminal nerve. As reported in the classical work of Wolff (1948), stimulation of these regions causes pain in the medial canthus of the supraorbital region. Periorbital pain due to middle turbinate compression against the septum or the lateral wall of the nose may be due to congestion of the nasal mucosa or to pneumatization of the middle turbinate (concha bullosa). The diagnosis is made by exclusion and requires a high index of suspicion, anterior rhinoscopy, computerized tomography (CT), and confirmation by the lidocaine test. We present five cases of middle turbinate headache syndrome, all with concha bullosa. Four were treated surgically by partial middle turbinectomy and septoplasty more than 1 year ago, with excellent results. One patient refused surgical treatment which was suggested after failure of medical treatment with antihistamines, decongestants, and a topical corticosteroid, and continues to be symptomatic. Despite the small number of cases studied, the authors concluded that the procedure used was effective for the resolution of headache.

Adult↗
PubMed1997

Secondary alcohol dehydrogenase as a marker of the conversion between progestagens and androgens in the rat testis.

Supraphysiological doses of LHRH-Analogue blocked the C21 to C19 steroid conversion in the mature Wistar rats testis. It was associated with inhibition of the NAD-dependent secondary alcohol-dehydrogenase (A-D II) histochemical reaction in the Leydig cells. Under this condition the treated group exhibited lower testis, seminal vesicle and prostate weights, intratesticular (IT) and plasmatic (PL) increased progesterone (P4) and decreased testosterone (T) concentrations. We also observed a decrease in the IT androstenedione (delta 4) concentration without pregnenolone (P5) change. All these data confirm a chemical castration pointing to a blockade at the level of the P450C21scc (17 alpha-hydroxylase/17-20 desmolase) enzyme complex. After hCG administration there is no difference in sexual gland weights, while steroid's biosynthesis are stimulated and all IT and PL steroid concentrations increase. A-D II showed a lower optical density in the LHRH-A treated groups and no differences in the hCG rats. The hydroxylase or lyase activity of the P450C21scc may change under certain hormonal conditions as occurs in adrenarche, probably due to conformational changes in the active site of the enzyme system since it is encoded by only one gene. We suppose that the secondary alcohol itself and not the coenzyme reacts with the enzyme active site inhibited by the LHRH-A, since the NAD dependent 3 beta, hydroxysteroid-dehydrogenase (3 beta HOST-D) is affected in the opposite sense. This study shows A-D II reaction as a marker of the mediated P450C21scc enzyme complex activity in the rat testis Leydig cells.

3-Hydroxysteroid Dehydrogenases↗
PubMed1996

Effect of chronic ethanol consumption on the activities of residual small bowel brush-border enzymes after proximal jejunum resection in the rat.

Ethanol consumption has a toxic effect on the epithelium of the small bowel, but enterocyte maturity is very difficult to measure under these circumstances. However, when ethanol intake is combined with enterectomy, enterocyte immaturity is greater, permitting an easier separation of these two effects. In a group of rats (13 male Wistar rats weighing approximately 220 g) fed a liquid diet containing 35% ethanol for 4 weeks after resection of the proximal jejunum, the residual small intestine brush border maltase, sucrase, and lactase activities were similar to those of a pair-fed control group (13 animals). However, alkaline phosphatase activity was decreased in the mucosa and in the enterocyte brush border, probably because of the lower activity of this enzyme in the jejunum-ileum remnant of the alcoholic group.

Alcoholism↗
PubMed1995

Ileum brush border alkaline phosphatase activity in an experimental model of chronic alcoholism after small bowel proximal resection in the rat.

Literature reports that chronically ingested ethanol induces changes in the morphology of the small bowel mucous membranes. It has a topical toxic effect on the epithelium of the proximal jejunum and a blood-borne effect on the epithelium of the ileum because its absorption is almost complete in the stomach, duodenum and proximal jejunum. In addition there are also reports showing stimulation of enterocyte proliferation after segmental intestine resection. In this report we compare a group of rats submitted to resection of the proximal jejunum and fed a liquid diet containing 35% of the total calories intake as ethanol for four weeks to its control pair-fed group. In both groups we studied the mucosal alkaline phosphatase (APase) activity by histochemical as well as biochemical methods. We found a decreased APase activity in the homogenate of the intestinal mucous membrane in the alcoholic group and a reduced enzymatic activity in the brush border of the ileum enterocytes, as demonstrated by histochemical qualitative and densitometric assays. The result suggests that this change in APase activity of the brush border may represent enterocyte immaturity induced by long-standing ethanol intake in the remnant ileum after proximal resection.

Alcoholism↗
PubMed1994

Fiber types distribution in the digastric muscle of tufted capuchin monkey (Cebus apella).

Fiber types distribution in the digastric muscle of tufted capuchin monkey was studied by means of NADH-TR, myosin-ATPase, after alkaline and acid preincubations and SDH histochemical reactions. Three different types of fibers were found presenting an equal distribution. The percentage and types of fibers were as follow: 18.2% SO (Slow Oxidative), 38.4% FOG (Fast Oxidative Glycolytic) and 43.4% FG (Fast Glycolytic). FG fibers revealed the largest area. The relatively high concentration of fast twitch (81.2%) seems to indicate this muscle is involved with the acceleration and fast speed of jaw movements. Aerobic metabolism represented by SO + FOG fibers (56.6%) suggests that this muscle possesses an additional role than that related to the lowering of the jaw.

Animals↗
PubMed1993

Pulmonary tumor embolism to arterial vessels and carcinomatous lymphangitis. A comparative clinicopathological study.

A prospective study of 222 consecutive autopsies of cancer cases was undertaken to investigate whether carcinomatous lymphangitis and pure arterial tumor embolism of the lungs are different clinicopathological entities. The lungs were removed as a block and 15 sections (three from each lobe) were analyzed. A protocol containing clinical (ie, dyspnea, cyanosis, right ventricular failure, engorgement of jugular veins, and peripheral edema as main cause of death) and morphological (ie, right ventricle thickness and dilatation, vascular sclerosis, pulmonary infarct) data were carefully recorded in each case. Arterial tumor embolism was detected in 19 cases (8.5%) and carcinomatous lymphangitis in 44 cases (19.8%). We found no differences in relation to signs and symptoms of arterial tumor embolism and carcinomatous lymphangitis, but respiratory distress as the main cause of death was significantly more frequent in the cases with arterial involvement by tumor emboli. Morphologically, however, right ventricular hypertrophy-dilatation, histological signs of pulmonary hypertension, and hemorrhagic infarcts were more prevalent in the cases with arterial tumor embolism. This study permits us to conclude that although arterial tumor embolism and carcinomatous lymphangitis are clinically similar diseases, they are morphologically different entities. Our results suggest that the most probable pathogenesis of pulmonary endarteritis and subsequent pulmonary hypertension is the injury to the vascular endothelium caused by the arrest of tumor emboli.

Carcinoma↗
PubMed1992

A prospective study of the morphological aspects of tumor involvement of the pulmonary vessels.

A prospective morphological study of tumor involvement of the pulmonary vessels (TIPV) was undertaken on 203 consecutive autopsy cases of malignancies. The lungs were removed as a block and 15 sections (3 from each lobe) were analyzed. Site of origin, histological type and staging of the tumor, topographic distribution of the tumor emboli in the lungs, right ventricular hypertrophy and dilatation, pulmonary infarct, pulmonary vascular sclerosis and lung metastases were recorded in each case. TIPV was detected in 84 (41.4%) cases, the highest frequency reported until now. In 28 cases, TIPV was considered to be the main cause of death. The breast, liver, and pancreas were primary sites in more than 50% of the cases in which TIPV was observed. TIPV was more prevalent in epithelial neoplasms and showed a strong correlation with advanced disease. There was no significant difference among topographic regions of the lungs. The cases with TIPV were correlated with a high frequency of right ventricular hypertrophy and dilatation, vascular sclerosis and pulmonary metastases but not with pulmonary infarcts.

Female↗
PubMed1992

Clinical aspects of tumour involvement of the pulmonary vessels.

The involvement of the pulmonary vessels by tumour emboli may lead to a clinical picture defined as 'subacute cor pulmonale'. Information about this syndrome has been limited to case reports and a few series. A study of 214 autopsied cancer patients was undertaken to investigate the clinical signs and symptoms of tumour involvement of the pulmonary vessels (TIPV). The lungs were removed as a block and 15 sections (3 from each lobe) were analyzed. Clinical data about right ventricular failure, dyspnoea, cough, pleuritic chest pain, cyanosis, engorgement of jugular veins, peripheral oedema, haemoptysis and haemoptoic sputum were obtained from the medical records of each patient. Tumour emboli were detected in 89 cases, and no respiratory symptoms were recorded in 39. The presence of dyspnoea and cyanosis were highly significant in the group with TIVP, and right ventricular failure and peripheral oedema showed slight significant differences between the patients with and without TIPV. The classical picture of subacute cor pulmonale was observed in 13 patients and TIPV was considered to be the main cause of death in 29 cases. Our results indicate that although the development of subacute cor pulmonale was rare in patients with cancer, TIPV may be suspected when the patient presents respiratory distress and should be included in the differential diagnosis of dyspnoea in cancer patients.

Humans↗
PubMed1992

Pulmonary tumor embolism to alveolar septal capillaries. An unusual cause of sudden cor pulmonale.

Although metastatic spread of tumor to the lungs is common, subsequent production of cor pulmonale is not. The involvement of pulmonary alveolar capillaries causing sudden cor pulmonale is very rare. We describe a patient who presented with chest pain and sudden shortness of breath. Autopsy disclosed diffuse pulmonary microembolism to septal capillaries caused by tumor cells from a squamous cell carcinoma of the cervix. To our knowledge, this is the second report of this kind of pulmonary tumor embolism.

Carcinoma, Squamous Cell↗
PubMed1991

Pulmonary tumour embolism from squamous cell carcinoma of the oesophagus.

Pulmonary tumour embolism and subacute "cor pulmonale" have been reported in association with tumours of different origins. Even though these features were first described in a patient with carcinoma of the oesophagus, the frequency and importance of oesophageal tumours as the source of pulmonary tumour embolism have not been studied. In the present investigation, the lungs of 16 autopsied patients with squamous cell carcinoma of the oesophagus were studied prospectively. The lungs were removed as a block and 15 sections (3 from each lobe) were analysed. Pulmonary tumour embolism was detected in 7 cases. The lymphatic vessels were involved in all of them, and were associated with arteries and arterioles in 2. 2 patients presented a classical picture of subacute cor pulmonale, and dyspnoea was present in 3 other cases. The present study permitted us to conclude that carcinomas of the oesophagus frequently evolve toward carcinomatous lymphangitis and that pulmonary tumour embolism should be included in the differential diagnosis of the dyspnoea presented by the patients.

Carcinoma, Squamous Cell↗
PubMed1991

Pulmonary tumor embolism to alveolar septal capillaries. A prospective study of 12 cases.

Pulmonary tumor embolism leading to subacute cor pulmonale has been extensively studied. However, to our knowledge, the involvement of pulmonary alveolar capillaries has not previously been studied in detail. A prospective study was conducted on 112 autopsied patients with cancer to determine the presence of microembolism in the alveolar septal capillaries. Fifteen sections of predetermined lung areas were obtained and examined. Tumor embolism to alveolar septal capillaries was detected in 12 cases (10.7%), with simultaneous involvement of other vascular territories in 11. Seven patients had dyspnea; four, right ventricular failure; four, hypertrophy of the right ventricle; and three, arterial vascular sclerosis. The present data have led us to conclude that pulmonary tumor embolism to alveolar septal capillaries occurs in association with the involvement of arterial or lymphatic vessels and should be analyzed within the context of the study of subacute cor pulmonale.

Capillaries↗
PubMed1990

Pulmonary tumor embolism from squamous cell carcinoma of the vulva.

Involvement of the pulmonary vessels by tumor emboli has been described from different primary sites of malignancy. A case of pulmonary tumor embolism due to squamous cell carcinoma of the vulva is reported. This form of pulmonary involvement has not previously been described in cases of vulvar carcinoma and it is rare in gynecologic neoplasms. The development of dyspnea with rapid clinical deterioration and fatality associated with multiple pulmonary emboli and histologic signs of pulmonary hypertension is well shown by this case.

Carcinoma, Squamous Cell↗
PubMed1990

[Ototoxicity].

Ototoxic drugs, the best known of which are aminoglucoside antibiotics, can cause irreversible lesions in the ciliate cells of the organ of Corti and the maculae and crests of the vestibular apparatus. The cellular lesion is linked to the formation of complex substances between the ototoxic drug and the polyphospho-inositides of the cellular membrane. Auditory and vestibular monitoring must be ensured permanently throughout the use of such drugs, especially in the presence of risk factors. The lesions induced experimentally in animals having studied by electrophysiological methods, with recordings of the cochlear and brainstem potentials, and by histological methods with the technique of surface preparation of the organ of Corti, and by electron microscopy.

Adult↗
PubMed1990

Effect of a luteinizing-hormone-releasing-hormone (LHRH)-analogue on the histochemistry of the secondary alcohol-dehydrogenase in the Leydig cells of the cat testis.

The histochemical activities of the enzymes alcohol dehydrogenase with propanol (A-D I) and isopropanol (A-D II) as substrates, 3- beta-hydroxysteroid dehydrogenase (3 beta .OHST-D), nicotinamideadenine dinucleotide phosphate (reduced form)-tetrazolium reductase (NADPH2-TR) and glucose-6-phosphate dehydrogenase (G6P-D) were studied in the testis of 6 cats daily injected with 20 micrograms/kg of the LHRH-analogue DTRP6-DGLY-10, LHRH-ethylamide (LHRH-A Group) and 3 cats injected with saline during 67 days. A morphometric analysis was done to evaluate the activity of the enzymes, its distribution and volume fractions of the Leydig cells with every activity. A-D II displayed a significant inhibition in the Leydig cells of the LHRH-A Group. There were no changes in the activities of G6P-D, 3 beta .OHST-D and NADPH2-TR, but it was possible to disclose some reduction of the volume fraction of the Leydig cells when the first two enzymes were used as its marker. This study corroborates that A-D II is a reaction in the pathway of steroidogenesis but does not explain whether it corresponds actually to 20-22 desmolase as proposed in the work by Hardonk (1965) or to another reaction linked to the activities of the cytochromes P450.

Alcohol Dehydrogenase↗