Biomedical subjects

M A Quesada

Publications and source records attributed to M A Quesada.

24 records · Page 2Linked to original sources

PubMed1991

[Progression of functional disability in 70 patients with multiple sclerosis].

We have carried out a follow-up study in 70 patients that were included in a follow-up protocol when they met the criteria of MS, so as to evaluate the variations in the disability scale per unit of time of follow-up (index of progression) in relation to the several risk factors. There were 31 females and 39 men followed up for 19.6 +/- 12 months. One half of the patients (35) had their first symptoms between 25 and 45 years of age, in 27 the onset was after age 25 and in 8 after age 45. At the end of follow-up 42 patients were classified as having remitting forms, 12 as progressive forms after a remitting phase and 16 as progressive forms from the onset. Significant differences in the evolutive forms were only found in remitting-progressive forms, which had a quicker progression than the purely remitting and chronic progressive forms. The patients who initially had cerebellar symptoms had a quicker progression than those with any other type of presentation. Whereas patients with late onset had a quicker progression than the group with intermediate onset, the patients with early onset had a slower progression.

Adolescent↗

PubMed1991

High-sensitivity DNA detection with a laser-excited confocal fluorescence gel scanner.

A high-sensitivity, laser-excited confocal fluorescence gel scanner has been developed and applied to the detection of fluorescently labeled DNA. An argon ion laser (1-10 mW at 488 nm) is focused in the gel with a high-numerical aperture microscope objective. The laser-excited fluorescence is gathered by the objective and focused on a confocal spatial filter, followed by a spectral filter and photodetector. The gel is placed on a computer-controlled scan stage, and the scanned image of the gel fluorescence is stored and analyzed in a computer. This scanner has been used to detect DNA separated on sequencing gels, agarose mapping gels and pulsed field gels. Sanger sequencing gels were run on M13mp18 DNA using a fluoresceinated primer. The 400-microns-thick gels, loaded with 30 fmol of DNA fragments in 3-mm lanes, were scanned at 78-microns resolution. The high resolution of our scanner coupled with image processing allows us to read up to approximately 300 bases in four adjacent sequencing lanes. The minimum band size that could be detected and read was approximately 200 microns. This instrument has a limiting detection sensitivity of approximately 10 amol of fluorescein-labeled DNA in a 1 x 3-mm band. In applications to agarose mapping gels, we have exploited the fact that DNA can be prestained with ethidium homodimer, followed by electrophoresis and fluorescence detection to achieve picogram sensitivity. We have also developed methods using both ethidium homodimer and thiazole orange staining which permit two-color detection of DNA in one lane.(ABSTRACT TRUNCATED AT 250 WORDS)

Base Sequence↗

PubMed1990

[Intrathecal secretion of antiviral antibodies in multiple sclerosis in patients in Seville].

To assess the presence of antiviral antibody synthesis in the cerebrospinal fluid in patients with multiple sclerosis, concurrent plasma and spinal fluid determination of antibody titers against measles, varicella-zoster, rubella, mumps, cytomegalovirus, and herpes viruses were performed in 29 samples and were compared with a control group. The study revealed an increased titre of antiviral antibodies in the spinal fluid in patients with multiple sclerosis. This increased activity was markedly significant for the varicella-zoster and cytomegalovirus in patients with clinical symptoms of multiple sclerosis. There was also and increased antibody titre against cytomegalovirus and varicella-zoster in patients with well defined illness. No antibody reaction was observed in the control group. The study of the antiviral antibody activity in the spinal fluid in patients with multiple sclerosis is useful in the follow-up control and in the diagnosis of the disorder specially in our community, where the investigation of antibodies anti cytomegalovirus appears to be the most appropriate method due to its high sensitivity and absence of false positive tests.

Antibodies, Viral↗

PubMedDate not supplied

Neuroradiologic abnormalities in Marchiafava-Bignami disease of benign evolution.

Marchiafava-Bignami disease has been recognized since 1903, but only recently has it become possible to achieve a probable diagnosis before death occurs. Imaging of the central nervous system with MR and CT have contributed significantly to such a diagnosis. Two cases of the disease are reported in patients, aged 33 and 59 years, with benign evolution of neurologic symptoms the diagnosis was confirmed by neurologic imaging with MR and CT and both were studied with evoked responses. Reversibility of the disease and possible prognostic indicators in these and other patients reported in the literature are discussed. The important role that diagnostic procedures, especially MR imaging, play in the management of this disease is emphasized.

Adult↗

PubMedDate not supplied

[Correlation between magnetic resonance and disability scales (EDSS and ISS) in multiple sclerosis].

In the present study the lesions in MRI imaging were quantified and compared with the clinical and functional abnormalities in 56 patients (27 females and 29 males) with definite multiple sclerosis (MS). The evolution was relapsing in 30, there were relapses followed by progressive evolution in 10, and evolution was progressive from the onset in 16. A good correlation was found between the disability scale EDSS and total lesions in MRI (r = 0.45), and also with the disability scale EDSS and hemispheric (r = 0.45) and centrioval (r = 0.41) involvements and with lesions near the third ventricle (r = 0.32). The clinical parameters predicting a greater surface of involvement in MRI were late onset (beyond 45 years) and progressive evolution. The best correlation between disability scale and MRI lesions was found between EDSS and periventricular (lateral ventricles) lesions (r = 0.46). The linearly correlation between both disability scales was good (r = 0.86), but it improved when an exponential equation was used (r = 0.91). This could allow to use the more simple scale (ISS) with a mathematical transformation. When the patients with a greatest surface of involvement were compared with the remaining MS patients, significant differences were found for nearly all evaluated disability items. Patients with greater involvement surfaces in MRI had greater disability.

Adult↗

PubMedDate not supplied

[Chronic demyelinating polyneuropathy associated with multiple sclerosis: a patient with two diseases].

We studied the clinical, paraclinical and laboratory findings of a patient suffering from multiple sclerosis (MS) with chronic demyelinating polyneuropathy. As well as being a new case of demyelination of the central and peripheral nervous system not normally associated with the presence of antiganglionic antibodies, our patient presented clinical signs distinct from each disease with the characteristic abnormalities of cerebrospinal fluid (CSF) (cytological albumin dissociation at the moment when an outbreak appeared at the peripheral level and an increase in intrathecal secretion when the outbreak was at the central nervous system level). Demyelinating diseases of the central and peripheral nervous systems are a field of great interest in trying to find the antigenic bull's eye for MS.

Adult↗