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Biomedical subjects

A Machado

Publications and source records attributed to A Machado.

207 records · Page 12Linked to original sources

The influence of age on neurotransmitter turnover in the rat's superior colliculus.

Measurements of the turnover of dopamine, noradrenaline and serotonin and their metabolites have been performed in the superior colliculus of adult and aged rats. The turnover of dopamine, noradrenaline and their metabolites after pargyline treatment was significantly lower in aged rats than in adults. On the contrary, the synthesis rate of serotonin (measured by accumulation of 5-hydroxytryptophan after decarboxylase blockade) and the turnover rate of serotonin (after pargyline treatment) did not change during aging. These findings suggest that aging has a different effect on catecholamines and serotonin turnover in the superior colliculus of the aged rats.

3,4-Dihydroxyphenylacetic Acid↗

[Leprosy. Comparative study of old and new patients].

Leprosy represented, until a few decades ago, an important public health problem in mainland Portugal. According to the data of the General Directorate of Primary Health Care, the incidence and prevalence rates of the disease have been decreasing progressively and in a significant way during the last years. In view of the fact that it is an endemic disease in regression, we decided to estimate if there were significative changes in the clinical manifestations of the new cases. Therefore, we carried out a comparative study based on the clinical data of 18 patients (13 males and 5 females) with Leprosy who were being followed up in the Dermatology Clinics of Coimbra University Hospital. We differentiated two groups: patients with the diagnosis of the disease before 1990 (old patients), and those diagnosed after 1990 (new patients). The first group had only 8 subjects while the second group had the other 10. We recorded the patients' age, sex, nationality and residence, age at the onset of the disease, number of cases that began before the age of 20, clinical manifestations (according to Ridley and Jopling's classification), and the presence of incapacity determined by the consequences of the disease. We carried out the Student's-t test to appreciate some of the study parameters. We verified that the old patients were on average 11 years younger than the new patients. Leprosy in new patients occurred 11 years later than in the old patients and this difference was statistically significant after the Student's-t test (p < 0.05). Almost one half of the new cases (4 patients in 10) were possible cases of leprosy brought from Brazil, while all the old individuals had an autochthonous origin. The multibacillary forms were predominant in both groups, representing 89% of all patients. The frequency of handicaps was similar in both groups. Although it is based on a small number of patients, our study suggests that the clinical and epidemiological manifestations of leprosy have been changing significantly in the last years and that the changes observed in the form of presentation of the new cases are consistent with the present epidemiological situation. Our study also seems to suggest an increase in the importance of leprosy imported by immigrants from leprosy endemic countries. We point out that this phenomenon, as in the case of AIDS, can theoretically create the conditions for a recrudescence of leprosy, as currently observed with tuberculosis.

Adult↗

[Can sural nerve biopsy be used to orientate the treatment of chronic inflammatory demyelinating polyneuropathy?].

INTRODUCTION: Chronic inflammatory demyelinating polyneuropathy (CIDP) is an acquired neuropathy characterized by demyelination of the peripheral nerves and roots. The course of the illness is progressively chronic or of relapses and remissions. Biopsy of the sural nerve is not essential for diagnosis. It is therefore not necessary to carry it out on all occasions, but probably permits a more rational approach to treatment. OBJECTIVE: To show whether biopsy of the sural nerve is useful for orientation of the treatment required in cases of CIDP. PATIENTS AND METHODS: We studied a total of 16 patients admitted to hospital with a diagnosis of CIDP. They had neurophysiological studies, sural nerve biopsy and other studies to rule out other diagnoses. The patients were assigned to the therapeutic protocols recommended. During 8 years of follow up we compared the response to treatment with intacglobin/plamapheresis, steroids and cytostatic drugs. RESULTS: It was highly significant (p< 0.001) that the patients with axon lesions on sural nerve biopsy did not respond to treatment with intac globin/plasmapheresis or steroids but did respond to cyclophosphamide, without any serious adverse effects being seen. CONCLUSIONS: Axonal histopathological lesions of CIDP at the onset of the disease may require cytostatic treatment since they do not usually improve on standard treatment. Sural biopsy is usually invaluable in such cases.

Adult↗

[Endoscopic retrograde cholangiopancreatography and sphincterotomy in parasitic diseases].

We report six patients with billary duct obstruction due to parasites (Fasciola hepatica, ascariasis and hydatid cyst) that were diagnosed and managed with the endoscopic approach. This is the first national paper which highlights the importance of endoscopic retrograde cholangiopancreatography in the management of this parasitosis. Despite choledocholithiasis as the most common cause of extrahepatic jaundice, biliary tree parasitosis must be considered in the differential diagnosis.

Adolescent↗

[Non small cell lung cancer - comparison between clinical and pathological staging].

Lung cancer (LC) staging remains a clinical challenge as it determines the disease's prognosis and treatment. Surgery is the best option for controlling non-small cell lung cancer (NSCLC) and the only potential cure. In this setting, lung cancer staging helps select patients who will benefit from surgery, excluding inoperable patients and including patients with resectable lesions. The aim of this study is to compare clinical staging (TNMc) with pathological staging (TNMp) and to evaluate diagnosis, complementary treatment and survival of these patients. This is a retrospective study that included patients with non-small cell lung cancer or with highly suspicious lesions who had undergone surgery and were followed up in the Hospital de São João lung cancer unit between January 1999 and December 2003. It is based on clinical files and pathology reports. 73.3% of this group of 60 patients were male, with median age 59.2 years. The most frequent TNMc stages were 41.7% T1N0M0 and 36.7% T2N0M0. Thoracotomy for therapeutic purpose was per- formed in 80% and thoracotomy for diagnostic purpose also in the remaining 20%. In 6.7% the resection was incomplete. The most frequent TNMp stages were T2N0p in 33.3%, T2N1p in 15.0% and T2N2p in 13.3%. There was a significant difference between the two staging types, with upstaging in 65.0%, down staging in 67% and only 28.3% keeping the same stage. The most frequent differences were from T1N0c to T2N0p and from T2N0c to T2N1p. The global agreement between both staging methods was 21.7%. Median global survival was 43 months. In conclusion, while clinical staging was less accurate, it did not determine important changes in therapeutic strategy and survival. For the future, we should consider using other diagnostic tools and other biological factors to complement the anatomical information that we currently use.

Adult↗

Direct quantitative determination of peptides and proteins in PVDF transfer membrane using a computing densitometer.

In this paper we describe a method that makes it possible to quantify bands or spots directly on membranes using a computing densitometer. The method is based on the fact that polyvinylidene difluoride (PVDF) membrane is translucent when immersed in solutions containing > 50% methanol. Peptide markers (2.512-16.949 kDa), as well as purified Neuropeptide Y, have been used to optimize direct densitometry of PVDF membrane. For all peptides and proteins analyzed, the optical response of the instrument to peptide and protein bands in PVDF membrane wetted in 50% methanol was linear and highly reproducible. The method described here is useful for a rapid quantification of peptides and proteins on PVDF membrane and is an alternative to RIA, ELISA or bioassay.

Blotting, Western↗

[Tuberculosis: a forgotten challenge].

Tuberculosis continues to be a serious problem in public health even thought eh causative bacillus was discovered over 100 years ago. The authors present a clinical case that illustrates the current concern regarding the disease. The case concerns a child of emigrant parents, who are drug addicts and whose illness has not been fully ascertained. The child was hospitalised at three and an half months with fever, malnutrition, opisthotonos and hepatosplenomegaly. After the diagnosis of disseminated tuberculosis affecting the central nervous system, treatment was started with five antituberculosis drugs and with corticosteroids. Respiration improved favourably, but after 19 days the patient suffered a partial tonic-clonic seizure. Subsequently, hydrocephalus was observed and a shunt was applied. Bacteriological examination of the gastric aspirate showed a strain of Mycobacterium tuberculosis resistant to isoniazid and streptomycin. In the eight month of therapeutics, three antituberculosis drugs were still being administered, the shunt was still present and the patient showed a severe psychomotor retardation. The child belonged to a risk group and presented a serious form of tuberculosis with multidrug-resistance, illustrating that this group of children is particularly vulnerable and reflect transmission of this illness among adults.

Central Nervous System Diseases↗