PubMed Health⌕ Search

Biomedical subjects

A Villa

Publications and source records attributed to A Villa.

At least 343 records · Page 19Linked to original sources
PubMedDate not supplied

Cardiac thrombus in Omenn syndrome.

Omenn syndrome is characterized by a generalized erythematous skin rash, lymph node enlargement, hepatosplenomegaly, Increased serum IgE levels, eosinophilia, and evidence of severe combined immune deficiency. Patients develop fungal, bacterial, and viral infections. We present the case of a 3-month-old girl with Omenn syndrome who developed right ventricular thrombosis. Echocardiographic study revealed a round structure that filled the apex and corpus of the the right ventricle. We investigated this patient for hypercoagulation and made a diagnosis of ventricular thrombosis, which is an uncommon finding in Omenn syndrome.

Echocardiography↗
PubMedDate not supplied

Age-related changes in calcium homeostatic mechanisms in synaptosomes in relation with working memory deficiency.

Aging is associated with alterations in different systems that govern neuronal calcium homeostasis. This study was designed to determine whether any of these alterations may contribute to the decline in spatial working memory that is observed in old rats. Several parameters [initial (5 s) and steady state (15 min) 45Ca2+ uptake, FCCP-releaseable 45Ca2+, [Ca2+]i levels, depolarization-induced phosphoprotein (P97, PP65, P42) dephosphorylation and acetylcholine levels and release) involved in calcium homeostasis/signaling were determined in whole brain synaptosomes derived from adult (9-month-old) and old (24-month-old) rats that were evaluated for spatial memory performance in the eight-arm radial maze. The neurochemical analysis indicated that both the 9- and 24-month-old rats were impaired with respect to 3-month-old animals. When learners (animals reaching criterion; RC) were compared to memory impaired rats (MI), it was found that the FCCP-releaseable 45Ca2+ of synaptosomes, that reflects mitochondrial calcium, was lower in the MI than the RC rats and was correlated with the behavioral performance of the rats in their first testing sessions. The results suggest that the loss of calcium uptake capacity in synaptic mitochondria during aging may be associated with impaired working memory in old animals.

Acetylcholine↗
PubMedDate not supplied

Predictive and prenatal diagnosis of Huntington's disease: attitudes of Mexican neurologists, psychiatrists, and psychologists.

BACKGROUND: Huntington's disease (HD) is a hereditary disease of the central nervous system. Its molecular diagnosis has allowed predictive and prenatal diagnosis to be done, and it is now a model for the study of the ethical, legal, and social problems arising from the diagnosis of such diseases. METHODS: This study explores the knowledge and attitudes of a group of Mexican specialists regarding the disease and its diagnosis. A self-administered, 30-item multiple-choice questionnaire was completed anonymously by neurologists, psychiatrists, and psychologists. RESULTS: Fifty-five percent of the professionals had experience with HD patients, 59% claimed to know the hereditary risks, and 20% answered incorrectly concerning the risks. Neurologists had the most exposure to HD; 74% acknowledged the existence of predictive diagnosis, although only 10% knew the international guidelines for testing. Eighty-six percent of the participants recommended predictive diagnosis, the reasons being: 55%, if the patients considered having offspring; 41%, for the patient's professional reasons; 6%, if a treatment was available, and 12% did not answer. In cases in which the patient wanted to have offspring, 38% thought that this should be avoided. Thirty-six percent of the subjects considered prenatal diagnosis justified in a couple with a carrier, and 51% justified abortion for affected fetuses. CONCLUSIONS: Genetic counseling and predictive diagnosis in Mexico must be the responsibility of genetics units and specialists who are aware of inheritance risks and of guidelines for HD programs. The number of patients requiring such attention is increasing rapidly.

Adult↗
PubMedDate not supplied

A phase I-II trial of high-dose ifosfamide in patients with ovarian cancer refractory or resistant to platinum and/or paclitaxel-containing chemotherapy.

AIMS AND BACKGROUND: To evaluate the toxicity of high-dose ifosfamide in ovarian cancer patients refractory or resistant to platinum and/or paclitaxel-containing chemotherapy. METHODS: This was an open, non-randomized phase I-II trial of high-dose ifosfamide. Eligibility criteria were: patients aged 18-75 years affected by ovarian cancer with refractory or resistant disease or early relapse after first-line treatment including platinum or paclitaxel. Three patients were given escalating ifosfamide doses; if no severe adverse events occurred, the ifosfamide dose was increased. The starting dose of ifosfamide was 10 g/m2 i.v. and the dose increase was 1 g/m2 every four weeks for a total of five courses; 12 g/m2 was the maximum ifosfamide dose to be administered. The trial then progressed to a phase II trial, in which ifosfamide was given at the maximum tolerated dose reached during the escalating dose phase. RESULTS: A total of 36 patients entered the trial. Nine patients were involved in phase I of the study; 3 received 10 g/m2 ifosfamide, 3 11 g/m2 and 3 12 g/m2. Of the 32 evaluable patients 6 (18.8%) achieved a complete response and three (9.4%) a partial response, giving an overall response rate of 28.1% (95% CI, 15-61% based on Poisson's approximation). The median number of ifosfamide courses was five. G1, G2 and G3 neurotoxicity was reported in 3 (8%), 2 (5%) and 2 (5%) patients, respectively. CONCLUSION: This phase I-II trial indicates that high-dose ifosfamide has some activity but also a relevant degree of toxicity in resistant or refractory platinum and paclitaxel-pretreated ovarian cancer.

Adult↗
PubMedDate not supplied

Lack of TdT and immunoglobulin and T-cell receptor gene rearrangements in Hodgkin's disease.

To study the pathogenesis of Hodgkin's disease (HD), which today remains obscure, we have undertaken a combined experimental approach: determination of TdT and molecular analysis of rearrangements of immunoglobulin heavy chain (IgH), T-cell receptor (TCR) beta chain and the T-cell rearranging gamma (TRG) genes. TdT determination indicate would the presence of immature cells that are not detected in the normal lymphnode; molecular analysis of the rearrangements of these genes would reveal the presence of even a small monoclonal population of both T and B lineages in the lymphnodes. We believe that the combination of these two types of analysis can indicate whether an expanding lymphoid clone is responsible for this disease. TdT determination was negative in all 41 cases tested. Gene rearrangements were studied in 10 cases for IgH and TCR beta genes and in 5 cases for the TRG gene. No abnormal band beside the germ-line ones was detected in any of our cases, ruling out the presence of a minor neoplastic population. We can explain these results in at least three ways: first, the neoplastic population could represent less than 1% of the total, thus escaping detection by current techniques; second, the neoplastic population is not lymphoid in nature or is composed of mature cells that do not rearrange Ig and TCR genes and therefore belongs to a true non-B, non-T lineage; third, the pathogenesis of HD is completely different from that of non-Hodgkin's lymphomas (NHL) and does not involve the clonal expansion of a cell frozen at a particular maturative stage as is thought to happen in most NHL.

DNA Nucleotidylexotransferase↗
PubMedDate not supplied

Detection of malignant primary hepatic neoplasms with gadobenate dimeglumine (Gd-BOPTA) enhanced T1-weighted hepatocyte phase MR imaging: results of off-site blinded review in a phase-II multicenter trial.

OBJECTIVE: To investigate the efficacy of gadobenate dimeglumine (Gd-BOPTA) enhanced MR imaging for the detection of liver lesions in patients with primary malignant hepatic neoplasms. MATERIALS AND METHODS: Thirty-one patients with histologically proven primary malignancy of the liver were evaluated before and after administration of Gd-BOPTA at dose 0.05 or 0.10 mmol/kg. T1-weighted spin echo (T1W-SE) and gradient echo (T1W-GRE) images were evaluated for lesion number, location, size and confidence by three off-site independent reviewers and the findings were compared to reference standard imaging (intraoperative ultrasound, computed tomography during arterial portography or lipiodol computed tomography). Results were analyzed for significance using a two-sided McNemar's test. RESULTS: More lesions were identified on Gd-BOPTA enhanced images than on unenhanced images and there was no significant difference in lesion detection between either concentration. The largest benefit was in detection of lesions under 1 cm in size (7 to 21, 9 to 15, 16 to 18 for reviewers A, B, C respectively). In 68% of the patients with more than one lesion, Gd-BOPTA increased the number of lesions detected. CONCLUSION: Liver MR imaging after Gd-BOPTA increases the detection of liver lesions in patients with primary malignant hepatic neoplasm.

Adenoma, Liver Cell↗
PubMedDate not supplied

Magnetic resonance imaging in the study of ischemic heart disease.

In ischemic heart disease, as compared to other procedures, Magnetic Resonance Imaging (MRI) offers the advantage of providing in a single diagnostic session an ample and reliable multiparametric analysis. The technological advances of recent years have been increasing exponentially and marked qualitative refinements are thus predictable in the near future for morphological, functional, perfusional and metabolic studies.

Coronary Circulation↗
PubMedDate not supplied

[Prevalence of multiple sclerosis in Colombia].

INTRODUCTION: Multiple sclerosis (MS) is the commonest demyelinating condition of the nervous system. It is characterized by numerous demyelinating areas or plaques of demyelination which are found dispersed throughout the nervous system. It has been shown that MS is less frequent in tropical regions than in subtropical regions. In Latin America particularly, there are some studies which show this phenomenon. However, in Colombia no studies of prevalence of MS have been done. OBJECTIVE: To determine the prevalence of multiple sclerosis in five provinces of Colombia (Antioquia, Caldas, Santander, Risaralda and Bolivar). PATIENTS AND METHODS: The capture-recapture method was used for two sources to determine the number of cases defined on the criteria of Poser et al seen between July 1995 and June 2000. RESULTS: The prevalence (cases of MS per 100,000 inhabitants) varied between 1.48 in Antioquia (95% CI 1.12; 1.78) and 4.98 in Risaralda (95% CI 3.52; 6.43). Seventy two percent were women. The regions included in this study represented 25% of the population of Colombia. CONCLUSIONS: There is a low prevalence of MS which is as expected in tropical areas. Persons with MS in these regions may be very useful in the study of other factors involved in the aetiology of MS (genetic). The capture-recapture method is an excellent tool for carrying out prevalence studies since it is cheap and requires little time.

Colombia↗
PubMedDate not supplied

MR of the hypothalamic-pituitary axis in Langerhans cell histiocytosis.

PURPOSE: To describe the MR findings in the hypothalamic pituitary area in children with Langerhans cell histiocytosis and to define those MR alterations especially associated with the risk of developing diabetes insipidus. METHODS: The hypothalamic-neurohypophyseal axis was studied by sagittal and coronal 1.5 T1-weighted MR imaging in 14 children with Langerhans cell histiocytosis (five with diabetes insipidus) and in 28 low-stature controls, ages 6-14 years. RESULTS: The pituitary stalk was thicker in seven/14 patients (three with diabetes insipidus) than in controls (P less than .05). Bright posterior pituitary signal was undetectable in children with diabetes insipidus and in one/9 without diabetes insipidus. CONCLUSIONS: Thickening of the hypothalamus and/or the pituitary stalk in the absence of the posterior pituitary bright signal is seen in children with Langerhans cell histiocytosis with overt diabetes insipidus. Those Langerhans cell histiocytosis patients without diabetes insipidus but showing thickened stalk with or without posterior pituitary bright signal could be at high risk to develop diabetes insipidus.

Adolescent↗