Biomedical subjects

M C Negrete-García

Publications and source records attributed to M C Negrete-García.

8 recordsLinked to original sources

PubMed2006

CC chemokine ligand 1 is released into the airways of atopic asthmatics.

CC chemokine ligand (CCL)1/I-309 is a potent attractant for T-helper cell type 2 lymphocytes. The present study investigates whether this cytokine is released in the bronchoalveolar fluid (BALF) of asthmatic patients. Measurements of CCL1 using ELISA showed that levels of this cytokine were significantly elevated in BALF from asthmatics compared with normals (median (range) 193 (120-449) pg.mL(-1) versus 30 (21-55) pg.mL(-1)). Differential cell counts in BALF showed that either lymphocyte or eosinophil numbers were elevated in asthmatic compared with normal subjects (10.8 x 10(3).mL(-1) versus 1.0 x 10(3).mL(-1) and 1.7 x 10(3).mL(-1) versus 0.2 x 10(3).mL(-1), respectively). There was a trend towards a significant correlation between CCL1 levels and lymphocyte numbers in BALF. Separation of BALF using sequential CCL1 affinity column and reverse-phase high-performance liquid chromatography allowed detection of biologically active CCL1. Using immunohistochemistry, CCL1 immunoreactivity was localised predominantly to the airway epithelium. Interestingly, there was a significant correlation between CC chemokine ligand 1 levels and epithelial cell numbers in bronchoalveolar lavage fluid and between these cells and lymphocyte numbers. Moreover, interleukin-4, interleukin-13 and interferon-gamma stimulated primary bronchial airway epithelial cells to release CC chemokine ligand 1. These findings suggest that CC chemokine ligand 1 may play a role in lymphocyte recruitment in bronchial asthma.

Adolescent↗

PubMed2003

Interleukin (IL)-4 and to a lesser extent either IL-13 or interferon-gamma regulate the production of eotaxin-2/CCL24 in nasal polyps.

BACKGROUND: Eotaxin-2/CCL24 is a potent eosinophil attractant that has been implicated in the recruitment of eosinophils in allergic disease. We have investigated whether the cytokines interleukin (IL)-4, IL-13, and interferon (IFN)-gamma regulate eotaxin-2/CCL24 in nasal polyps. METHODS: Nasal polyps were cultured in the presence of the cytokines described above and the concentration of eotaxin-2/CCL24 was measured in the culture supernatant. RESULTS: IL-4 was found to be the major stimulus for eotaxin-2/CCL24 production from nasal polyps followed by IL-13 and IFN-gamma. IL-4 induced eotaxin-2/CCL24 in a dose-dependent manner with concentrations as low as 0.1 ng/ml being able to induce eotaxin-2/CCL24. By immunohistochemistry, eotaxin-2/CCL24 immunoreactivity was localized to mononuclear cells in the IL-4 stimulated nasal polyp tissue. Interestingly, nasal turbinates obtained from patients suffering from nonallergic rhinitis (vasomotor rhinitis) were also found to release eotaxin-2/CCL24 both spontaneously and following cytokine stimulation with IL-4 and IFN-gamma being major inducers of this cytokine. CONCLUSIONS: All together these findings suggest that Th1 and Th2 cytokines may regulate eotaxin-2/CCL24 production in nasal polyps and nonallergic rhinits.

Adult↗

PubMed1992

Anti-dsDNA and Sm autoantibodies in systemic lupus erythematosus.

During the present study the coincidence of anti-dsDNA and Sm antibodies was detected in 16 percent of 51 consecutive SLE patients. These antibodies were detected by the standard indirect immunofluorescence and Ouchterlony tests. All patients with anti-dsDNA and Sm antibodies showed disease activity, including renal, CNS and pulmonary disease. We excluded a cross reactivity of these antibodies by ELISA, using competitive experiments with dsDNA and Sm antigens. The results support the presence of multiple autoantibody production during SLE activity, and suggest that different mechanisms may underlie the induction and regulation of both autoantibodies.

Adolescent↗

PubMed1991

[Thrombocytopenic purpura and hemolytic anemia in children with generalized lupus erythematosus].

We studied 30 children with systemic lupus erythematosus in order to detect the clinical, pathological and serological findings associated with the development of thrombocytopenic purpura and hemolytic anemia. A group of 13 of the 30 children revealed hematological manifestations as the most prominent changes of SLE. Thrombocytopenic purpura and hemolytic anemia were the beginning manifestation of SLE in 11 children. Different causes, for these hematological changes such as hypersplenism, renal microangiopathy or drugs reactions were excluded by history and examination. Interestingly, other immunohematological manifestations including splenomegaly and lymphadenopathy were more frequent in children with thrombocytopenic purpura and hemolytic anemia, than in those patients without these hematological complications. Positive antiplatelet antibodies were found in 4/6 children with thrombocytopenia and 2/5 with hemolytic anemia. A relation of antiplatelet with anticardiolipin antibodies occurred in 4 patients; 3 of them in children with thrombocytopenic purpura and one with hemolytic anemia. Anti-dsDNA and anti-Sm antibodies were positive in almost all patients. Four children shown a transition from anti-dsDNA to anti-Sm antibodies or viceversa and all of them revealed a significant variation in the titer of these antibodies by ELISA, in relation with disease activity. The presence of hematological manifestations associated with anti-platelet and anti-cardiolipin antibodies in children with SLE support that different mechanisms triggers autoimmunity in childhood.

Adolescent↗

PubMed1989

[Generalized sclerosis (scleroderma) in children].

Five patients with childhood scleroderma, were studied from a total group of 50 cases with the disease, 39 of them with diffuse systemic sclerosis and 11 with the CREST syndrome. The average age for these five patients when the disease onset was 13 (the age ranged from 5.5 to 16 years) with an average follow-up of 3.6 years (ranging from 1 to 6.5 years). Of the five, four girls were classified as having diffuse systemic sclerosis and the remaining boy, as suffering from the CREST syndrome. We found no family history or personal and occupational antecendents related with the appearance of the illness. Also excluded were conditions associated with changes similar to scleroderma as are seen in cases of diabetes mellitus, phenylketonuria, toxic oil syndrome, or graft-host rejection reactions. The clinical manifestations seen at the start of the disease included the Raynaud phenomenon, subcutaneous edema and muscular-skeletal abnormalities as arthralgia and myalgia with objective data of inflammatory myopathy. Proximal scleroderma was seen in all five patients; three of them, in addition, developed rapidly progressive cutaneous changes, causing the loss of elasticity and cutaneous hardening of the face during the first year of the disease. In all of the cases, the skin biopsy showed histopathological changes compatible with the diagnosis already given. The most important changes seen in the organs of these children were oesophageal dysfunction and fibrosis of the lung. The X-rays of three of the patients showed them to suffer from intestinal malfunction. We found no kidney, liver or nervous system disorders.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1989

[Autoantibodies in juvenile rheumatoid arthritis. Clinical and serologic study].

Twenty five patients with juvenile rheumatoid arthritis were studied in order to define the frequency and kind of circulating autoantibodies in this entity, as well as, their relationship with the different disease subgroups and complications. Also the association of these autoantibodies with the activity stage of the illness was determined. There were 14 pauciarticular, 8 polyarticular and 3 systemic juvenile rheumatoid arthritis patients. Twelve have a flare of the disease and 13 were completely asymptomatic. Rheumatoid factor measured by the latex agglutination tests was positive in 6 children. These included 2 patients with pauciarticular disease, showing titers below 1:40 and 4 cases with polyarticular disease, showing titers above 1:320. One of these last patients developed and adult type rheumatoid arthritis during her evolution and was treated with D-penicillamine. The polyarticular but not the pauciarticular patients showed positive tests for rheumatoid factor by nephelometry. No definite association between these laboratory results and the activity of the disease was noted. Positive antinuclear antibodies by the indirect immunofluorescence test were found in 3 pauciarticular and one polyarticular patients. A predominant homogeneous staining was found with the mouse kidney substrate, whereas homogeneous and speckled patterns were noted with the homologous HEp-2 cells. One patient with persistent positive antinuclear antibodies revealed uveitis. Three of the 4 sera with positive antibodies by the indirect immunofluorescent test have also anti-nucleoprotein antibodies by the hemagglutination test with titers above 1:32.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1989

[Systemic lupus erythematosus in children with renal and hematologic manifestations. Relation to anti-nDNA antibodies].

We studied prospectively 22 children with systemic lupus erythematosus. Serologic tests included: immunoglobulins, C3 and C4 determinations. Antinuclear antibodies, by the indirect immunofluorescence test, anti-nDNA, anti-nRNP, anti-Sm and anti-SSB (La) studies were also obtained. From the 22 patients there were 16 girls and 6 boys. The mean age at the onset of the disease was 12.4 years (range 8-15 years). Four patients had the disease before being 10 years old. We mainly observed two clinical subgroups, those with kidney injury, which included 11 patients (50%), and a second group of 8 patients (36%) with prominent hematologic manifestations, 4 with hemolytic anemia and 4 with thrombocytopenic purpura. The patients with kidney disease included 7 with diffuse proliferative glomerulonephritis, one with focal and one with mesangial glomerulonephritis. No biopsies were obtained in two patients. From the group with hematological disturbances, only one patient with hemolytic anemia developed renal involvement during her evolution. Three of the 22 patients presented lymphoproliferative disorders in coexistence with systemic lupus erythematosus. The presence of anti-nDNA antibodies and the decrease of C3, were statistically associated with kidney disease, but not with the hematologic manifestations. Nevertheless 50% of patients with hemolytic anemia and thrombocytopenic purpura have positive anti-nDNA and low C3 determinations. If immunochemical differences between the anti-nDNA antibodies in these groups of patients with systemic lupus erythematosus can establish a distinction in their clinical evolution with or without nephropathy is an interesting question that remains to be determined.

Adolescent↗

PubMedDate not supplied

Rheumatoid factor activity in serum and bronchoalveolar lavage fluid from patients with acute hypersensitivity pneumonitis.

The presence of rheumatoid factor was detected in both serum and bronchoalveolar lavage fluid (BALF) from patients with acute pigeon breeder's disease. IgM rheumatoid factor was positive in 14 of 20 serum samples and 6 of 20 BALF samples by ELISA. In contrast, negative results were found in 20 healthy subjects with a history of avian antigen exposure, as well as in the serum and BALF from 10 normal subjects. The simultaneous presence of rheumatoid factor in serum and BALF occurred in five patients, and four of them revealed high levels of rheumatoid factor in BALF in comparison with serum determinations. These abnormalities may play an important role during the acute inflammatory reaction in hypersensitivity pneumonitis.

Adult↗