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Biomedical subjects

J M Ballester

Publications and source records attributed to J M Ballester.

At least 19 recordsLinked to original sources
PubMed2000

Expression and functional activity of the very late activation antigen-4 molecule on human natural killer cells in different states of activation.

In the present study we describe the expression and functional activity of the alpha4beta1 heterodimer molecule on human natural killer (NK) cells. Flow cytometric analyses showed that fresh and activated NK cells expressed high levels of very late activation antigen-4 (VLA-4) molecules. These cells bound to fibronectin (FN) and to its 38 000-MW proteolytic fragment through the VLA-4 integrin that was blocked with HP2/1 anti-alpha4 monoclonal antibodies (mAbs) and with the FN peptide fragment CS1. No inhibitory effects were observed in the presence of anti-alpha5 mAb, FN peptide fragment CS2 or other irrelevant mAb. Fresh NK cells were unable to aggregate, despite their expression of VLA-4, and only activated (cultured and lymphocyte-activated killer cells) NK cells showed homotypic aggregation with HP1/7 and HP2/4 anti-alpha4 mAb related to cellular activation. These results underline new evidence of how NK cells in different states of activation maintain different constitutive levels of alpha4beta1 integrin activity, and highlight the possibility of a different functional regulation by the cells bearing VLA-4, in the expression of these epitopes and their ability to interact with their ligands.

Cell Adhesion↗
PubMed1999

Hypothermia: an easy-to-miss, dangerous disorder in winter weather.

A variety of age-related physiologic factors and disease states predispose older patients to hypothermia. These include a decreased ability to produce heat, malnutrition, medications, infections, and social factors such as isolation and poverty. The subtle clinical signs and symptoms of mild hypothermia may mimic cognitive decline, cerebral vascular accident, hypothyroidism, or myxedema coma. The challenge for the physician is to clinically recognize hypothermia and provide prompt diagnosis and treatment. Medical management of the older patient with moderate to severe hypothermia requires in-hospital intensive care, as life-threatening conditions may arise during stabilization and resuscitation.

Aged↗
PubMed1999

[Antineutrophil cytoplasmic antibodies in patients with sickle cell anemia].

PURPOSE: To determine whether anti neutrophil cytoplasmic antibodies (ANCA): anti myeloperoxidase (anti MPO) and anti proteinase 3 (anti PR3), are present in patients with sickle cell anaemia (SCA) during painful crisis. PATIENTS AND METHODS: 55 patients with SCA were included in this study, 35 of them had painful crisis and the rest were in steady state. We determined levels of anti MPO and anti PR3 by two enzyme immunoassays commercially available (Progen Biotechnik GMBH). RESULTS: A significant increase of anti MPO in the group of patients with painful crisis was found in comparison with steady state patients and controls. CONCLUSIONS: Our results suggest the possibility that anti MPO interacting with MPO on primed neutrophils lead to neutrophil activation, enhanced neutrophil adhesion and amplification of endothelial cell damage.

Adolescent↗
PubMed1984

Dengue haemorrhagic fever in Cuba. II. Clinical investigations.

Clinical and serological studies were carried out on 114 patients admitted to hospital in Havana, Cuba with Dengue Haemorrhagic Fever and Dengue Shock Syndrome (DHF/DSS). Serological confirmation of dengue was obtained in 90% of cases, with 5% of cases primary and 95% secondary. Fever, haemorrhagic manifestations, vomiting and headache were the most frequent signs and symptoms. Among haemorrhagic manifestations, petechiae and vaginal bleeding were reported in a larger number of patients. 21 patients presented shock and, of these, 20 were secondary infections. The disease appeared more frequently in white persons and in women. The aetiopathogenicity of the syndromes is discussed. 95% of the cases could be explained on the basis of the secondary infection hypothesis.

Adolescent↗
PubMed1982

Circulating immune complexes in paroxysmal nocturnal hemoglobinuria.

Circulating immune complexes were investigated in sera of 13 patients with paroxysmal nocturnal hemoglobinuria. A significant inhibition was observed in the complement-dependent rosette formation (EAC) in 6 cases; 2 patients presented an increased anticomplementary activity; antilymphocyte antibodies were demonstrated in 2 patients. The levels of C3d and immunoconglutinins were also increased; there were no differences in the total hemolytic complement between patients and normal controls. There was a significant correlation between C3d and immunoconglutinins with the inhibition of the EAC rosette formation test. These results provide evidence for the presence of circulating immune complexes in paroxysmal nocturnal hemoglobinuria.

Adult↗
PubMed1982

Cell-mediated immunity in chronic myelocytic leukemia.

14 patients with chronic myelocytic leukemia were evaluated immunologically; no difference was found in mean lymphocyte percentage and absolute number between patients and healthy subjects. 4 cases (28.5%) showed decreased percentage of T lymphocytes, while only 2 cases (14.2%) had decreased absolute T lymphocyte values. PHA transformation was decreased in 57% of the patients. Spontaneous transformation in the short-term cultures exceeded the normal range in 65% of the cases. All patients skin tested were found to be reactive. Most of the patients had defective cellular immune response in vitro, probably related with a qualitative defect in T lymphocyte subpopulations. It cannot be completely excluded that part of the observed lymphocyte depression was due to the busulfan.

Adult↗
PubMed1981

Sarcoidosis associated with autoimmune haemolytic anaemia and paroxysmal nocturnal haemoglobinuria red cell abnormality.

A 29-year-old male with sarcoidosis autoimmune haemolytic anaemia and paroxysmal nocturnal haemoglobinuria is described. Throughout his illness the chest films showed fibrosis in the right hilar region and he had had several pneumonias in the right lung. He had had massive splenomegaly and a splenectomy was performed. He was treated with prednisone and cyclophosphamide. Because his blood group was initially confused, several incompatible blood transfusions were given. Two types of antibody were detected: an autoantibody with "s" specificity and an alloantibody with Rh "D" specificity. Other interesting features in this case revealed at autopsy were a viral pneumonia and Toxoplasma gondii infection of the brain. As far as we know, this is the first reported patient with this unusual association.

Adult↗
PubMed1980

Purification of the viridicin produced by Aerococcus viridans.

A new bacteriocin produced by Aerococcus viridans was purified. Bacteria grown on liquid medium synthesized a bacteriocin, viridicin, which can be extracted from the cells by treatment with 0.86 M NaCl solution. Viridicin production was not induced by ultraviolet irradiation or by treatment with mitomycin C. The bacteriocin was purified by ultrafiltration, gel filtration, and preparative polyacrylamide disc gel electrophoresis. The molecular weight was between 100,000 and 120,000. The purified viridicin was homogeneous on polyacrylamide gel electrophoresis. The viridicin was composed of protein, carbohydrate, and lipid.

Bacteriocins↗
PubMed1980

HLA antigens in paroxysmal nocturnal hemoglobinuria.

10 patients with paroxysmal nocturnal hemoglobinuria were studied taking 109 normal subjects of the Cuban population as control group. 26 HLA antigens corresponding to loci A and B were studied in both groups. Phenotypical frequency of both groups were compared. No statistically significant increase was found for any of the studied antigens, though there was a nonsignificant increase for antigens HLA-B7 and BW-21. These results might be influenced by the small number of patients studied due to the rareness of the disease.

Gene Frequency↗
PubMed1980

Immunologic dysfunction in Sickle cell anaemia.

Selected cellular immune parameters were studied in 20 patients with sickle cell anaemia (SCA). A moderate absolute lymphocytes was observed in SCA patients compared with the control group. There was no significant difference between patients and controls in the mean E-rosette percentage and absolute number. PHA transformation was decreased in 50% of SCA patients, and some of them showed cutaneous anergy. It was suggested that imparied cell-mediated immunity is another factor to be included among defective SCA host-defense mechanism.

Adolescent↗
PubMed1976

A study of the genetical structure of the Cuban population: red cell and serum biochemical markers.

Gene frequencies of several red cell and serum gentic markers were determined in the three main racial groups--whites, mulattoes and Negroes--of the Cuban population. The results were used to estimate the relative contribution of Caucasian and Negro genes to the genetic makeup of these three groups and to calculate the frequencies of these genes in the general Cuban population.

Acid Phosphatase↗