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O M Takayanagui

Publications and source records attributed to O M Takayanagui.

At least 37 records · Page 2Linked to original sources
PubMed1997

Enantioselective analysis of albendazole sulfoxide in plasma using the chiral stationary phase.

We present a method for the enantioselective analysis of albendazole sulfoxide (ABZSO) in plasma for application in clinical pharmacokinetic studies. ABZSO enantiomers were separated on a 5-micron Chiralcel OB-H column (4.6 x 150 mm) using hexane:ethanol (93:7, v/v) as the mobile phase and fluorescence detection. ABZSO was extracted with chloroform:isopropanol (8:2, v/v) from 500-microliter aliquots of acidified plasma, with full drug recovery. The proposed method presented quantitation limits of 20 ng/ml for (-)ABZSO and 50 ng/ml for (+)ABZSO and was linear up to a concentration of 5,000 ng/ml of each enantiomer.

Adult↗
PubMed1997

Therapy for neurocysticercosis: pharmacokinetic interaction of albendazole sulfoxide with dexamethasone.

Albendazole is considered the drug of choice for neurocysticercosis. It is frequently used in combination with dexamethasone to prevent the acute inflammatory reaction due to cysticercal death. It has been reported that dexamethasone increases the plasma level of albendazole sulfoxide, the active metabolite of albendazole. The pharmacokinetic interaction of albendazole sulfoxide with dexamethasone, associated or not with cimetidine, was investigated in 24 patients with active intraparenchymal brain cysticercosis. Eight of these patients received albendazole alone, eight received it in combination with dexamethasone, and eight received it in combination with both dexamethasone and cimetidine. The pharmacokinetic parameters maximum plasma concentration, time to maximum plasma concentration, absorption half-life, and absorption rate constant did not differ between groups, suggesting that the formation of albendazole sulfoxide was not altered by the administration of dexamethasone, combined or not with cimetidine. There were significant differences, however, in the parameters plasma concentration-time curve, oral clearance, elimination half-life, and elimination rate constant, suggesting that dexamethasone, combined or not with cimetidine, decreases the rate of elimination of albendazole sulfoxide.

Adolescent↗
PubMed1997

Moyamoya disease in Brazil.

INTRODUCTION: Moyamoya disease was first believed to be confined to Japan, but over the years it has been reported all over the world. We report seven cases from the University Hospital of the Faculty of Medicine of Ribeirão Preto, University of São Paulo with a review of the previously described cases in Brazil. MATERIAL AND METHODS: The diagnosis was based on the diagnostic criteria of the Research Committee on Spontaneous Occlusion of the Circle of Willis. RESULTS: Five patients presented ischemic and two hemorrhagic events. The meta-analysis of the six cases previously described in Brazil showed that only two were true moyamoya disease according to the diagnostic criteria. CONCLUSION: We can assume that the real frequency of moyamoya disease has been underestimated in Brazil.

Adolescent↗
PubMed1996

[Compulsory notification of cysticercosis in Ribeiräo Preto-SP, Brazil].

Cysticercosis is a severe public health problem in several regions of Asia, Africa and Latin America. Epidemiologic studies based on the frequency of cases observed in specialized neurology, neurosurgery and computed tomography services, at autopsy and in seroepidemiologic studies do not permit the determination of the true prevalence of the disease in the population. The objective of the present study was to investigate the prevalence of cysticercosis by compulsory notification. The coefficient of prevalence was 54 cases/100,000 inhabitants in the municipality of Ribeirão Preto. The results also indicated that cysticercosis is not under control in our region since 21% of cases presented the active form of the disease. Compulsory notification proved to be a valuable resource for the epidemiologic study of cysticercosis, also permitting the mapping of more affected areas for a better direction of prevention strategies.

Adolescent↗
PubMed1994

Cysticercosis of the central nervous system. II. Spinal cysticercosis.

The compromising of the spinal canal by cysticercus is considered infrequent, varying from 16 to 20% in relation to the brain involvement. In the spinal canal the cysticercus predominantly places in the subarachnoid space. Clinical signs in spinal cysticercosis can be caused by direct compression of the spinal cord/roots by cysticerci and by local or at distance inflammatory reactions (arachnoiditis). Another mechanism of lesion is degeneration of the spinal cord due to pachymeningitis or circulatory insufficiency. The most frequent clinical features are signs of spinal cord and/or cauda equina compression. The diagnosis of spinal cysticercosis is based on evidence of cerebral cysticercosis and on neuroradiological examinations (myelography and myelo-CT) that show signs of arachnoiditis and images of cysts in the subarachnoid space and sometimes, signs of intramedullary lesions, but the confirmation can only be made through immunological reactions in the CSF or during surgery. The clinical course of 10 patients with diagnosis of spinal cysticercosis observed among 182 patients submitted to surgical treatment due to this disease are analyzed. The clinical pictures in all cases were signs of spinal cord or roots compression. All but two presented previously signs of brain cysticercosis. Neuroradiological examinations showed signs of arachnoiditis in 4 patients, images of cysts in the subarachnoid space in 5, and signs of arachnoiditis and images of cysts in one. The 6 patients that presented intraspinal cysts were submitted to exeresis of the cysts and 2 patients with total blockage of the spinal canal underwent surgery for diagnosis. The 2 remaining patients with arachnoiditis and blockage of the spinal canal were clinically treated. All of the six patients submitted to cyst exeresis had initial improvement but 4 of them later developed arachnoiditis and recurrence of the clinical signs and only 2 remained well for long-term. The 2 non operated patients had no improvement of their clinical signs. Two patients died later due to complications of cerebral cysticercosis. Based on the experience acquired in the management of these patients we indicate surgical treatment for patients that present free cyst in subarachnoid space. For those who present arachnoiditis, surgery is indicated only when there is doubt in the diagnosis. Intramedullary cysts should also be surgically treated.

Adolescent↗
PubMed1994

Chagasic meningoencephalitis with detection of Trypanosoma cruzi in the cerebrospinal fluid of an immunodepressed patient.

We report a case of chagasic meningoencephalitis with the detection of Trypanosoma cruzi in the cerebrospinal fluid (CSF). The patient was a renal transplant recipient with a chagasic history preceding surgery who had been receiving immunosuppressive medication for 8 years, a probable cause of the recrudescence of Chagas' disease. He was treated with benznidazole, with normalization of the CSF. He was discharged from hospital in a good clinical condition.

Adult↗
PubMed1993

[Chronic nervous form of Chagas disease: clinical course and anatomopathology of a case followed-up for 20 years].

The chronic nervous forms of Chagas' disease involve both the central and peripheral nervous systems although they are not detected at the frequency indicated by Chagas in his initial observations. The present report concerns a patient with chronic Chagas' disease since childhood who progressively developed involvement of voluntary motility, muscle tone, coordination, and cranial nerves. The patient also had Chagas' heart and colon disease. The patient died after surgery for hemicolectomy and was autopsied. Histologic study of the central nervous system revealed demyelination of the spinocerebellar tracts and posterior columns, a great reduction in the Purkinje cells number, extensive cell loss of the substantia nigra and locus coeruleus, lacunar state in the basal nuclei, tissue infiltration by aberrant Herring bodies, porencephaly, and thickening of the meninges.

Adult↗
PubMed1992

Therapy for neurocysticercosis. Comparison between albendazole and praziquantel.

Praziquantel and albendazole have been recently described as effective drugs for treatment of intraparenchymal brain cysticercosis. We performed a prospective study comparing the efficacy of these drugs. Twenty-two patients were treated with praziquantel and 21 with albendazole. In addition, 16 patients were treated with symptomatic drugs only and used as controls. Treatment was discontinued in two patients receiving praziquantel and one patient receiving albendazole owing to acute decompensation of the increased intracranial pressure, and one of them died. Albendazole and praziquantel were effective when compared with the control group. However, albendazole was significantly more effective than praziquantel in reducing the total number of cysts in the computed tomographic scans (88% vs 50%). Despite these results, however, analysis of clinical course showed a high frequency of neurologic sequelae. Considering the risks and fallibility of anticysticercal therapy, the real solution for this serious disease continues to be prophylaxis of infestation.

Adolescent↗
PubMed1990

[Neurocysticercosis. I. Clinical and laboratory course of 151 cases].

Neurocysticercosis is a serious public health problem in our midst, which accounted for 7.3% of the hospital admissions and 2.7% of all cases of the out patient clinic attendance of the Discipline of Neurology of the School of Medicine--Ribeirão Preto, São Paulo University, from 1979 to 1986. A total of 151 patients with a minimum follow-up of 6 months were selected for the present study including clinical and laboratory evolution, a topic which is rarely considered in the literature. The onset of the disease was characterized by: epileptic seizures in 82 patients (54.3%), increased intracranial pressure (ICP) in 40 (26.5%), meningitis in 21 (13.9%), headache in the absence of increased ICP or meningitic signs in 7 (4.6%), and spinal cord syndrome in 1 (0.6%). In the group with the epileptic form, 36.6% of the patients later developed other neurological syndromes, such as cysticercotic meningitis, mental disorders and increased ICP after a 6 to 7 years interval. In the group with the hypertensive form, 55% of the patients developed other manifestations during the period of evolution, especially meningitis and epileptic seizures, after a significantly shorter interval than for the epileptic form. In the meningitic form, 19% of the patients showed a recurrence of the syndrome after a mean interval of 10.7 weeks: an additional 66.6% developed a combination with other syndromes, especially increased ICP and epileptic seizures. The death rate was 7.9%, the main cause being increased ICP (83.3%). When the abnormalities of the complementary tests were investigated in the various forms of clinical presentation in terms of their predictive value it was concluded that, in the epileptic form, the presence of cysts in CT scan and/or abnormalities in CSF indicates a greater risk of developing other neurologic syndromes. No significant differences in the patterns of abnormalities of these investigations were detected in the remaining clinical forms. Most cystic lesions detected by CT scan (90.9%) were associated with CSF abnormalities, especially pleocytosis and positive complement fixation test. Conversely, this proportion was only 26% in patients with calcifications.

Adolescent↗
PubMed1990

[Neurocysticercosis. II. Evaluation of treatment with praziquantel].

The results of the use of praziquantel (PZQ) for the etiologic treatment of neurocysticercosis (NC) are presented. The drug was administered to 45 patients (24 women and 21 men) at increasing doses of 10 to 50 mg/kg/day during the first week and with maintenance on the last dose for two additional weeks, preferentially for patients that presented intraparenchymatous cystic lesions in the computed axial tomography. Follow-up ranged from 8 months to 4 years and a half (median, 2.7 years). During PZQ administration 27 patients (60%) presented side effects which required interruption of treatment in three cases. Decompensation of the increased ICP occurred in two cases (one of them fatal). Exacerbation of CSF pleocytosis occurred in 26 patients (57.7%). Evaluation of the results of PZQ treatment showed a lower clinical-laboratory rate of success than reported in the literature. The most appropriate indications for the use of PZQ are discussed on the basis of the present data and of reports by other investigators. In view of the risks and fallibility of treatment with PZQ, the solution of NC resides in the prevention of infestation.

Adolescent↗
PubMed1983

[Clinical aspects of neurocysticercosis: analysis of 500 cases].

This was a retrospective study, made at the Hospital das Clinicas University of São Paulo Medical School--Ribeirão Preto from 1956 to 1979 in 500 patients with neurocysticercosis. To our knowledge, this represented the largest sample analysed so far. Clinical manifestations and complemmentary tests were studied. The neurocysticercosis is a serious endemic disease in our region and represented 2.7% of all clinical evaluations by the Neurology Department and 7.5% of all hospital admissions. The most frequent clinical presentations were the epileptic (64.8%), the intracranial hypertension (35.6%), and the meningitic (29%). Radiological study of the skull showed intracranial calcifications suggestive of cysticercosis in 47.6%. The cerebrospinal fluid was abnormal in 81.3%: pleocytosis in 60.9%, increased protein in 49.1% and increased pressure in 29%. The presence of eosinophils occurred in 41.9%, and the Weinberg test was positive in 62,6% of all the cases. It was discussed the utility of the different drugs and the results of the surgical treatment in neurocysticercosis drawing the conclusion that they show no efficacy when analysed at the end of a long follow-up. Since none of the drugs seems to be really efficient, only the sanitary education will be able to control this endemic disease that grasses among us with so somber perspectives.

Adolescent↗
PubMed1981

[Epilepsy and chronic Chagas disease].

The epileptic syndrome in chronic Chagas' disease is rarely reported in neurological literature. At the present time many papers have demonstrated that histopathological basis of Chagas' disease is a neuronal destruction. The authors studied 167 epileptic patients; 44 out of them had a chronic form of the disease. It was made a comparison of semiologic data between the two groups, and also the evaluation of the therapeutic results with anticonvulsant drugs. The chagasic patients had the onset of epileptic seizures later than the control group, with great predominance of partial seizures of autonomic type. The neurologic examination and cerebrospinal fluid test revealed moderate rates of disturbances, but not sufficient to characterize a neurologic syndrome. The EEG study was performed in 15 of the 44 cases and revealed a suggestive pattern of a diffuse cerebral damage in half of patients. Anticonvulsant therapy based on use of phenylhydantoin, barbituric acid derivates, primidone and benzodiazepines, showed that control of epileptic seizures in Chagas' diseases is more difficult and requires greater quantities of drugs than in the control group.

Adolescent↗
PubMed1981

[Myelopathy caused by histoplasmosis: report of a case].

A case of myelytic syndrome caused by histoplasmosis is reported. The patient had an acute paraparesis with impairment of all types of sensibility at T11-T12 level, with loss of sphincter control. The laminectomy revealed meningeal thickness and granulomatosis, microscopically identified as H. capsulatum. Intrathecal and parenteral therapy with amphotericin B, gave poor results.

Adult↗
PubMedDate not supplied

Determination of albendazole metabolites in plasma by HPLC.

Albendazole is an antihelminthic agent belonging to the benzimidazole class and has been used successfully in the treatment of neurocysticercosis. We report here a method for the determination of the two major albendazole metabolites in plasma, albendazole sulfone and albendazole sulfoxide. The method consists of drug extraction from 500 microL of plasma previously acidified with chloroform-isopropanol (9:1, v/v) and extract purification with n-hexane immediately before chromatographic analysis. Separation of drugs and of the internal standard (mebendazole) was performed on an RP-18 column using acetonitrile-0.25N sodium acetate buffer (3:7, v/v), pH 5.0, as the mobile phase and using detection at 290 nm.

Adolescent↗
PubMedDate not supplied

[Cryptococcus meningitis: clinical course, development and histopathologic aspects depending on the predisposing factors].

Seventeen consecutive cases of cryptococcal meningitis diagnosed at Hospital das Clínicas of Ribeirão Preto Medical School (São Paulo State Brazil) between 1969 and 1985 were reviewed. For analysis the patients were separated in 3 groups: I. three patients without immunodeficiency; II. six patients with associated disease: cancer (3), diabetes (2) and alcoholism (1); III. Eight renal transplant recipients that developed cryptococcosis after 18 to 67 months of immunosupression with steroids and azathioprine. The median interval between onset of symptoms and diagnosis of infection was greater in Group II (53 days) than in Groups I (25 days) or III (28 days). Neck stiffness, cranial nerve involvement and papilledema were more frequent in Group I than in Group II or III, but fever and focal neurological signs were observed only in patients of two last groups. Cerebrospinal fluid examination showed a mild lymphocytic pleocytosis in most patients, but transplant cases had polymorphonuclear cells more frequently. Late mortality was higher in patients with underlying disease and the prognosis was better for transplant patients that received effective antifungal therapy. Besides cryptococci, autopsy findings in 8 cases revealed granuloma formation in tissues, except in patients of Group II (2 cases). The differences between the groups suggest that clinical characteristics, evolution and postmortem findings of the cryptococcal meningitis are changed according to type of immunodeficiency presented by the patient.

Adolescent↗