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Biomedical subjects

C Silva

Publications and source records attributed to C Silva.

At least 91 records · Page 5Linked to original sources
PubMed1994

Quality in obstetrics using a telematic system.

A telematic based system for antenatal care has been developed to be used in service integration between primary and secondary health care units. The system is based on low cost platforms and has a user friendly human computer interface. This system will provide better integration and coordination between the health care providers involved, improving the quality of the services. This experiment is being funded in the framework of the EC.Project-A 2007-EPIC. Quality indicators, agreed in the "European concensus conference of quality indicators for perinatal care", organized in conjunction with OBSQID project (AIM.2125) were integrated in the system. Data collection has started and the outcome will be used to validate the indicators on a transeuropean basis under the framework of the OBSQID Project.

Data Collection↗
PubMed1994

[Neurosyphilis and human immunodeficiency virus (HIV-1)infection. Experience with 6 cases].

HIV infected population has a higher incidence of syphilis, being this an independent risk factor for HIV infection. We report 88 HIV infected patients seen during the last three years. Fourteen (16%) had reactive serum VDRL and FTA-ABS and neurosyphilis was diagnosed in six (6.8%). Three had a treponemal uveitis-retinitis, one a meningovascular syphilis and one a secondary syphilis with meningeal and otological involvement. Patients were treated with penicillin 20 million UI/day for 14 days with good clinical and laboratory response and CSF normalization in those subjected to a second lumbar puncture. It is concluded that neurosyphilis must be considered in the differential diagnosis of neurological complications of HIV infections.

Acquired Immunodeficiency Syndrome↗
PubMed1994

QSAR study on H3-receptor affinity of benzothiazole derivatives of thioperamide.

Starting from the structure of thioperamide, a known H3-antagonist, a new series of compounds with a benzothiazole nucleus instead of the cyclohexylcarbothioamide moiety was synthesized. Various substituents, selected by experimental design, were introduced in position 6 of the benzothiazole nucleus, in order to change its physico-chemical characteristics. The lipophilicity of the synthesized compounds was measured by means of RP-HPLC, and their H3-receptor affinity was evaluated by competitive binding assays on rat cortex synaptosomes, with the labelled ligand N alpha-[3H]methylhistamine. A QSAR analysis was performed on the experimental data, using also substituent constants taken from the literature. The newly synthesized compounds showed lower H3-affinities than thioperamide; quantitative structure-activity relationships, described by models obtained with PLS and MRA techniques, were observed among benzothiazole derivatives. According to these relationships, any attempt to improve the potency of these compounds should involve the substitution of the benzothiazole moiety with less bulky and/or more flexible structures, which should also be less lipophilic and allow better electronic interactions with the binding site. 1-(Benzothiazol-2-yl)-4-[(1H)-imidazol-4-yl]piperidine represents a limit structure for H3-activity, since it seems impossible to improve its affinity by means of substitution in the studied position of the benzothiazole nucleus, as shown by predictions performed by a PLS model.

Animals↗
PubMed1994

[Temporal lobectomy in refractory partial epilepsy. Report of 4 cases].

Thirty, out of 1200 patients of North Santiago Adult Epilepsy Program, were admitted to J J Aguirre Hospital due to refractory epilepsy. Looking for candidates for functional epilepsy surgery, these patients were evaluated by neurologists, psychiatrists and psychologists and with standard EEG, video monitored EEG, CAT scan, magnetic resonance imaging and SPECT. So far, four patients with temporal partial complex epilepsy have been studied, operated (anterior temporal lobectomy and amygdalo-hippocampectomy) and followed for more than one year. Of these, two are free of seizures, one has sporadic episodes and one has an important reduction. One of these patients had a postoperative amnestic syndrome of 3 to 4 weeks duration. According to these results and those reported in the literature, the rigorous selection of patients that could be benefitted by surgery is emphasized.

Adult↗
PubMed1993

An approach to histologically diagnosed gallbladder carcinoma following cholecystectomy for presumed benign disease.

Five cases of gallbladder adenocarcinoma treated at Surgical Department 2, Maciel Hospital, Montevideo, Uruguay, in a period ranging from 1985 to 1989 and follow-up to date are reported. All cases were first diagnosed by microscopic examination of the gallbladder, which had been removed for presumed benign disease; there were no intramucosal carcinomas, and 60% of the cases were classified as Nevin's stage II (submucosal and muscularis). Based on the pattern of spread (mainly direct hepatic infiltration, as well as venous and lymphatic involvement), our radical surgical treatment of gallbladder carcinoma includes cholecystectomy, extended lymphatic clearance (along the porta hepatis or R1, pre- and retroduodenopancreatic and hepatic artery R2, and celiac axis R3), and medial hepatectomy (segments, IV, V, and VIII according to Couinaud). Simple cholecystectomy is the treatment of choice in mucosal (T1) neoplasms; otherwise, histologically diagnosed gallbladder carcinoma following cholecystectomy for presumed benign disease calls for reoperation to achieve lymph node dissection and hepatic resection. Overall 2- and 3-year survival was 100% and 80%; mean survival was 50 months. Medial hepatectomy was selected according to gallbladder carcinoma patterns of spread and failures, and entails resection of the parenchyma most frequently involved without compromising liver function, in a quick and safe surgical procedure.

Adenocarcinoma↗
PubMed1993

Pharmacological profile of new thioperamide derivatives at histamine peripheral H1-, H2-, H3-receptors in guinea-pig.

The recent availability of potent and selective ligands, namely R-(alpha)-methylhistamine and thioperamide, led to conclusive progresses as regards histamine H3-receptor knowledge. The aim of this work is to investigate by in vitro tests the pharmacological properties of new amino and methyl derivatives of the H3-antagonist thioperamide. Such original compounds, developed by the modulation of the thioperamide imidazolyl moiety, were assayed at guinea-pig ileal contractile H1-, atrial chronotropic H2- and enteric neuronal H3-receptors. None of the drugs exhibited interaction with H1 or H2 sites. On electrically stimulated ileum, two of the thioperamide methyl derivatives competitively antagonized the inhibitory effect of the H3-agonist R-(alpha)-methylhistamine. On the basis of the Schild analysis, the more active isomer (compound IV) displayed an affinity at H3-receptors only five times lower than thioperamide. These results could contribute to elucidate further the structural features required to develop potent and selective H3-antagonists. On the other hand, to prove the hypothesized apparent heterogeneity between peripheral and central H3-sites, as emerged by pharmacological and binding studies, autoradiographic investigations are in progress.

Animals↗
PubMed1993

[Hepatotoxicity induced by valproic acid in adults. Report of 3 cases].

Valproic acid is a useful antiepileptic drug, with occasional gastrointestinal side effects. Hepatotoxicity is the most serious adverse reaction and, although rare, it can be fatal. Risk factors for hepatotoxicity are an age of less than two years, polytherapy and mental retardation; it has been rarely reported in adults. We report three mentally retarded adult patients receiving polytherapy, who developed valproic acid induced hepatotoxicity. Two patients had a symptomatic hepatitis with a concomitant paradoxical increase in seizure frequency and one an asymptomatic alteration of hepatic function tests. After discontinuing the drug, the hepatitis subsided. We conclude that hepatotoxicity must be considered as a possible side effect of valproic acid and we suggest some recommendations for its early detection.

Adolescent↗
PubMed1992

Synthesis and binding assays of H3-receptor ligands.

The preparation of a representative group of derivatives of the known H3-antagonist thioperamide is described. Binding affinity for histamine H3-receptors of thioperamide and its derivatives, which were obtained by substitution on the imidazole ring, was measured on rat brain cortex synaptosomes. Competitive binding assays were performed with two different labelled ligands, the physiological agonist [3H]histamine ([3H]HA) and the potent H3-agonist N alpha-[3H]methyl-histamine ([3]NAMHA). We observed a remarkable difference in Ki values obtained versus the two labelled ligands, both for thioperamide and its derivatives. In particular, 5-methylthioperamide showed a considerable selectivity for the system recognized by [3H]NAMHA, being about 100 times more potent versus this system than versus the system recognized by [3H]HA. On the basis of these observations, we suggest that it is necessary to consider this difference in evaluating the affinity of new compounds for the H3-receptors.

Animals↗
PubMed1992

4-(1,2-Benzisothiazol-3-yl)alkanoic and phenylalkanoic acids: synthesis and anti-inflammatory, analgesic and antipyretic activities.

Continuing their studies on benzisothiazolyl derivatives, Authors refer to the preparation and pharmacological properties of 4-(1,2-benzisothiazol-3-yl) alkanoic and phenylalkanoic acids. All substances were tested for anti-inflammatory, analgesic and antipyretic properties. As reference compounds, 1,2-benzisothiazolin-3-one and 4-(3-oxo-1,2-benzisothiazolin-3-yl) phenylacetic acid, as prototypes of benzisothiazolinonic derivation. Ibuprofen, as a prototype of substituted arylalkanoic acids, and Phenylbutazone were used. Analysis of the data leaded to the following conclusions. Introduction of the aryl moiety, passing from benzisothiazolylalkanoic to benzisothiazolyl-phenylalkanoic structures, produced a remarkable increase of activity. 2-[4-(1,2-benzisothiazol-3-yl)phenyl] propionic and 2-[4-(1,2-benzisothiazol-3-yl)phenyl]butyiric acids showed anti-inflammatory, analgesic and antipyretic properties comparable to those of Ibuprofen. Substantial differences in variations in activities were observed comparing the properties of benzisothiazolylphenylalcanoic acids with those of the benzisothiazolinonic series, object of preceding studies.

Animals↗
PubMed1992

[Treatment of patients with panic disorder and an elevated urinary excretion of MHPG using imipramine or clonazepam].

The response to treatment with imipramine or clonazepam was evaluated in patients with panic disorder. These patients had a high urinary 3-methoxy-4-hydroxy-phenylglycol 24 h-excretion and normal plasma lactate levels. Both drugs were efficient as anti-panic agents, but clonazepam resulted more efficacious than imipramine by the scores of Hamilton Anxiety or Depression Scales. Moreover, clonazepam also reduced the anticipatory anxiety.

Adult↗
PubMed1991

Anomalous responses to histamine stimulation of guinea-pig oesophageal muscularis mucosae.

The incomplete tachyphylaxis of the contractile response to the H1-stimulants observed on guinea-pig oesophageal muscularis mucosae seems to be H2- and H3-antagonist as well as atropine- and tetrodotoxin-resistant. Lidocaine and eserine partially prevented this process probably by a mechanism independent of their main activity. The dualistic antagonism exerted by mepyramine and methysergide on reproducible histamine responses could be explained by a kinetic condition of "hemi-equilibrium state" together with changes of drug-receptor interaction and by non-specific properties of methysergide. On the whole, the present data indicate that the role of histamine in this tissue has still to be defined.

Animals↗
PubMed1991

[Sneddon syndrome. Presentation of 2 cases].

Sneddon syndrome is a systemic non inflammatory arteriopathy characterized by the association of livedo reticularis, thrombotic cerebrovascular disease, coronary artery disease and hypertension. Middle age females are usually affected. It should be considered in the differential diagnosis of acute ischemic attacks in younger patients. It has been related to the antiphospholipid antibody syndrome. Treatment is based on control of hypertension and cardiovascular risk factors along with antiplatelet agents. Two cases meeting the clinical criteria outlined above are reported.

Adult↗