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Biomedical subjects

A Ruiz-Argüelles

Publications and source records attributed to A Ruiz-Argüelles.

At least 19 recordsLinked to original sources
PubMed2003

Cytokine production and expression of leucocyte-differentiation antigens by human mononuclear cells in response to mycobacterium tuberculosis antigens.

The aim of this work was to characterize a leucocyte-differentiation antigen or chemokine receptor that allows the identification of type 1 (T helper 1 (Th1), Tc1) and type 2 (Th2, Tc2) lymphocytes in short-term-cultured human peripheral blood mononuclear cells. In addition, we assessed the type of response induced by mycobacterial antigens in tuberculosis patients and healthy contacts. Cells were stimulated with an unfractionated culture filtrate or 30 kDa antigen from Mycobacterium tuberculosis. Then, CD4 and CD8 cell labelling was combined with CD30, CD27, CD28, CD45RA or CD45R0 staining, detection of intracellular interferon-gamma (IFN-gamma) or interleukin-4 (IL-4) and analysis by three-colour flow cytometry. In separate experiments, the expression of different chemokine receptors (CCR1, CCR3, CCR5, CXCR3 and CXCR4) was also studied. We found that none of the cell-surface molecules studied was preferentially expressed by Th1 or Th2 cells. Thus, our results indicate that these lymphocyte subsets cannot be identified in short-term-cultured mononuclear cells on the basis of preferential expression of the cell markers studied, and that it is necessary to look for additional molecules that allow the discrimination of Th1 and Th2 cells.

Adult↗
PubMed2001

Results of an outpatient-based stem cell allotransplant program using nonmyeloablative conditioning regimens.

Using nonmyeloablative, immunosuppressive, fludarabine (FLU)-based conditioning regimens, we have performed allogeneic peripheral blood stem cell transplants in 26 patients (8 with chronic myelogenous leukemia, 6 with acute myelogenous leukemia, 10 with acute lymphoblastic leukemia, 1 with myelodysplasia, and 1 with thalassemia major). Conditioning consisted of FLU/busulphan/cyclophosphamide/cyclosporin-A (CyA)/methotrexate, or FLU/melphalan/CyA/methotrexate. The median granulocyte recovery time to 0.5 x 10(9)/l was 11 days, whereas the median platelet recovery time to 20 x 10(9)/l was 12 days. Twelve patients did not need red blood cell transfusions, and 8 did not need platelet transfusions. In 21 individuals (81%), the procedure could be completed fully on an outpatient basis. Follow-up times range between 30 and 600 days: one patient failed to engraft and recovered endogenous hemopoiesis; six out of 26 patients developed acute graft-versus-host disease (GVHD) whereas 7/22 developed chronic GVHD. Twelve patients (46%) have died, nine of them with a relapsing disease and three with GVHD; median post-transplant survival (SV) was 300 days, whereas the 12-month SV was 42%. The 100-day mortality was 3.8% and the transplant-related mortality was 11.5%. This procedure is substantially less costly than its counterpart, using in-hospital myeloablative conditioning regimens, and it may represent another approach in the management of patients requiring an allogeneic stem cell transplant.

Adolescent↗
PubMed2001

Decreased dopaminergic tone and increased basal bioactive prolactin in men with human immunodeficiency virus infection.

OBJECTIVE: The aims of the study were: (1) to assess dopaminergic tone in a group of HIV infected men and the bioactivity and the molecular species of their circulating PRL in comparison with healthy men and (2) to search for a correlation between serum PRL and CD4+ T lymphocytes and viral load. DESIGN: In a cross-sectional study the effect of acute dopaminergic blockade with intravenous metoclopramide on serum PRL (both immunoreactive and biologically active), TSH and PRL circulating molecular isoforms was evaluated. PATIENTS: Twenty untreated HIV infected men category C2 or C3, mean (SD) age 26.9 (6.3) years, were compared to 14 clinically healthy HIV-negative men, age 25.4 (2.3) years. MEASUREMENTS: Under fasting conditions and following metoclopramide administration duplicate measurements of serum immunoreactive PRL, bioactive PRL (PRL dependent Nb2 lymphoma cell assay) and immunoreactive TSH were performed. The molecular species of circulating PRL were determined by immunoblot analysis, CD4+ T lymphocytes by flow cytometry and the viral load using a nucleic acid sequence-based amplification assay. RESULTS: In HIV infected men fasting bioactive (but not immunoreactive) PRL was higher (P = 0.03), but the stimulated PRL (both immunoreactive and bioactive) was lower than in healthy men throughout the test (P < or = 0.01). Fasting serum TSH was similar in HIV-infected and healthy men while its response to metoclopramide was absent in the former but not in the latter (P = 0.049). A 23.5-kD PRL was the predominant circulating isoform both in patients and healthy men. Considering HIV-infected and healthy men, CD4+ T lymphocytes correlated negatively with fasting bioactive PRL (P = 0.008) and positively with the area under the PRL (both immunoreactive and bioactive) curves (P < 0.001). The viral load was negatively correlated with the area under the curve of the bioactive/immunoreactive ratio (P = 0.008). CONCLUSIONS: The raised fasting bioactive PRL, the diminished response of both immunoreactive and bioactive PRL and the absent TSH response to metoclopramide in HIV infected men, suggest the existence of a decreased, but not absent dopaminergic tone. A monomeric form of PRL was the predominant circulating species, as in healthy men, and this hormone seems to be associated both with CD4+ T lymphocytes and the viral load.

Adult↗
PubMed2001

Serum prolactin is associated with apoptosis in men with human immunodeficiency virus infection.

We examined the in vivo and in vitro production of prolactin (PRL) in 20 untreated HIV-infected men compared to 14 uninfected men and its association with the cell cycle and apoptosis. Compared to uninfected men, the HIV-infected men had: (i) higher fasting serum bioactive (BIO) PRL; (ii) lower serum immunoreactive (RIA) and BIO-PRL responses to intravenous metoclopramide; (iii) greater BIO-RIA PRL ratio both fasting and during intravenous metoclopramide; (iv) lower percentage of non-stimulated PBMC in the G0/G1 phase, but a higher percentage in the S phase, of the cell cycle with normal response to Concanavalin-A; and (v) higher in vitro production of BIO-PRL by non-stimulated PBMC, which was blocked after Concanavalin-A. Fasting serum BIO-PRL positively correlated with the percent of non-stimulated PBMC in S + G2/M phases. The percentage of apoptotic PBMC negatively correlated with CD4+ T lymphocytes and with the area under the serum RIA-PRL curve, but positively correlated with the area under the curve for the BIO/RIA ratio. These results suggest that in these HIV-infected men: (i) a diminished dopaminergic tone may exist, as an adaptive mechanism attempting to survive; and (ii) BIO-PRL may participate as a cofactor in the stimulation of T-cell proliferation.

Adult↗
PubMed2001

Novel facts about an old marker: the LE cell.

For more than fifty years, lupus erythematosus (LE) cells were believed to result from in vitro opsonization of bare nuclei by serum antinuclear antibodies and their ultimate phagocytosis by neutrophils. Twenty years ago, we described that certain antinuclear antibodies could enter into viable cells, and later on, it was proved that penetration of anti-DNA antibodies into cells results in protracted active cell death. Recent findings indicate that the material engulfed by LE cells are apoptotic blebs as residuals of cells dying after penetration of anti-DNA antibodies. These observations not only change the interpretation of the presence of the LE cell phenomenon, but also stress the potential pathophysiological role of antibodies to intracellular antigens in autoimmune diseases.

Active Transport, Cell Nucleus↗
PubMed2001

Features of the engraftment of allogeneic hematopoietic stem cells using reduced-intensity conditioning regimens.

The features of the engraftment in 26 patients allografted using reduced-intensity conditioning regimen (8 with chronic myelogenous leukemia, 6 with acute myelogenous leukemia, 9 with acute lymphoblastic leukemia, 1 with hybrid acute leukemia, 1 with myelodysplasia and 1 with thalassemia major) were analyzed. Patients received a median of 10 x 10(8)/Kg mononuclear cells (range 1.6 to 22.9), and a median of 4.2 x 10(6)/Kg CD34 cells (range 0.3 to 14). There was a linear correlation between the number of infused mononuclear cells (MNC) and that of CD34 cells (r = 0.78, p = 0.002). Three patients (11%) failed to engraft; in those who engrafted, the median time to achieve > 500 granulocytes was 11 days (range 10 to 22), and the median time to achieve > 10,000 platelets was 12 days (range 10 to 41). The three patients who failed to engraft received less than 5 x 10(8)/Kg MNC (1.6, 4.6 and 4.9) and less than 0.5 x 10(6)/Kg CD34; however, five of eight patients who received less than 5 x 10(8)/Kg MNC still engrafted successfully. On the other hand, all the patients who received less than 0.5 x 10(6)/Kg CD34 cells failed to engraft. Within the group of patients who engrafted, it was found that those who received more than 7 x 10(6)/Kg CD34+ cells tended to earlier recover > 20 x 10(9)/L platelets (p = 0.02), and > 0.5 x 10(9)/L neutrophils (p = 0.06) before day 15, than those who received less than 7 x 10(6)/Kg CD34+ cells. No such association could be established between the number of MNC and the time for recovery. In these patients allografted using reduced-intensity conditioning regimens, the target doses of hematopoietic cell used were similar to those described for conventional allografts: The number of CD34 infused cells was significantly related to the possibility of failure to engraft and to the recovery rate of the hemopoiesis.

Adolescent↗
PubMed2001

Penetration of autoantibodies into living cells, 2000.

The formerly prevalent concept that intact autoantibodies could not penetrate into viable cells has been defeated by a large amount of experimental findings and clinical observations that indicate otherwise. The penetration of autoantibodies into living cells seems to participate in the pathogenesis of diverse autoimmune diseases, but it may also play a physiological role in healthy individuals. Although the fine mechanisms of the phenomenon remain to be elucidated, the potential use of penetrating autoantibodies as vectors to deliver molecules into cells, with diverse therapeutic purposes, has gained growing interest during the last few years.

Animals↗
PubMed2000

'LE cells' result from phagocytosis of apoptotic bodies induced by antinuclear antibodies.

Lupus erythematosus (LE) cells are believed to represent phagocytosis by granulocytes of cell nuclei whose DNA has been 'depolymerized' and opsonized by serum factors, most likely antinuclear antibodies and C3b. Since it is known that certain antinuclear antibodies are capable of inducing apoptosis after intracellular penetration; and that the resulting apoptotic bodies can be ingested by non-professional phagocytes, we decided to investigate the possibility that LE cells could result from the phagocytosis of apoptotic bodies induced by antinuclear antibodies. We demonstrate herein, through different methodological approaches, that the ingested material within LE cells corresponds to apoptotic bodies, and that the LE cell phenomenon can be reproduced, in the absence of other serum factors, by penetrating murine monoclonal anti DNA antibodies.

Animals↗
PubMed2000

Hematopoietic stem cell allografts using a non-myeloablative conditioning regimen can be safely performed on an outpatient basis: report of four cases.

Using a non-myeloablative, immunosuppressive, fludarabine-based conditioning regimen, we performed allogeneic peripheral blood stem cell transplants totally on an outpatient basis in four patients (two with chronic myelogenous leukemia, one with acute myelogenous leukemia and one with thalassemia major). The median granulocyte recovery time to 0.5 x 109/l was 10 days and the lowest absolute neutrophil count was 0.064 x 109/l; only one patient developed thrombocytopenia below 20 x 109/l. No patient required red blood cell transfusions and one was given a single prophylactic platelet transfusion. All patients are alive at 210-390 (median 285) days and have definite evidence of chimerism; one developed biopsy-proven GVHD on day 50, with a limited cutaneous rash. The procedure is less costly than its counterpart using myeloablative conditioning regimens and may represent another approach in the management of patients requiring an allogeneic stem cell transplant. Bone Marrow Transplantation (2000) 25, 131-133.

Adolescent↗
PubMed2000

Multidrug resistance-1 (MDR-1) in rheumatic autoimmune disorders. Part II: Increased P-glycoprotein activity in lymphocytes from systemic lupus erythematosus patients might affect steroid requirements for disease control.

BACKGROUND: Over-expression of the membrane glycoprotein called P-glycoprotein has been widely observed in a variety of both normal and neoplastic cells. P-glycoprotein is a pump molecule that transports hydrophobic drugs (including steroids) and toxins outside the cells, thus inhibiting their therapeutic or toxic effects. The gene encoding P-glycoprotein is named multidrug resistance-1 (MDR-1). OBJECTIVE: To evaluate the functional activity of P-glycoprotein in lymphocytes and monocytes from patients with systemic lupus erythematosus. METHODS: 30 systemic lupus erythematosus patients and 20 healthy controls were studied. Peripheral blood mononuclear cells isolated by gradient centrifugation were incubated in the presence of daunorubicin (a fluorescent drug extruded by P-glycoprotein) at 37 degrees C or 4 degrees C for 30 min. P-glycoprotein activity was then analyzed using flow cytometry. Results were expressed as the percentage of lymphocytes or monocytes with high P-glycoprotein activity (i.e., low fluorescence). RESULTS: Mean fluorescence values for lymphocytes and monocytes were comparable between patients and healthy controls. However, because our method allowed to measure P-glycoprotein function at the single-cell level, we were able to show that the mean percentage of lymphocytes with high P-glycoprotein activity was increased in the patients (11.51% +/- 14.3%) as compared to the healthy controls (0.71% +/- 0.57%) (P < 0.05). Moreover, P-glycoprotein activity was lower in the patients in clinical remission than in those with active disease. CONCLUSIONS: Our results suggest that P-glycoprotein function might affect glucocorticoid requirements in systemic lupus erythematosus.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1999

Primary thrombophilia in Mexico: a prospective study.

A group of 102 Mexican Mestizo patients with appropriate clinical features suggestive of primary thrombophilia was prospectively studied. Thirty-nine percent of them had activated protein C resistance, but only four patients displayed the factor V Leiden mutation. Five percent of the individuals were found to be protein C deficient, whereas 2% had protein S deficiency. No cases of abnormalities in antithrombin III, plasminogen, tissue-type plasminogen activator or plasminogen activator inhibitor were found. The low prevalence of the activated protein C resistance genotype, probably stemming from the genetic admixture of the Mexican Mestizo group is noteworthy.

Activated Protein C Resistance↗
PubMed1999

Chronic lymphocytic leukemia is infrequent in Mexican mestizos.

Chronic lymphocytic leukemia (CLL) is the most frequent leukemia in adults living in Western countries, and accounts for approximately 30% of adult leukemias. In a 15-year period in a single institution, we identified 19 patients with CLL in a group of 211 adults with leukemia (9% of adult leukemias). Of these 19 CLL patients, 8 had a Caucasian phenotype, 4 were born outside the country, and only 11 were Mexican mestizos. On the other hand, in a multicenter experience involving 1968 Mexican adults with leukemia, CLL represented 6.6% of the cases, a figure significantly lower than that reported in Caucasians (P < 0.01). CLL is the least frequent type of leukemia in Mexican mestizos, and this low prevalence may stem from the genetic origin of this racial group. The data also suggest a genetic predisposition of Caucasians to suffer from this disease.

Adult↗
PubMed1998

Report on the first Latin American Consensus Conference for Flow Cytometric Immunophenotyping of Leukemia.

On October 16, 1996, the first Latin American Consensus Conference for the Immunophenotyping of Leukemia took place in Puebla, Mexico, with representatives from 10 countries of the region and two external consultants. This document summarizes the major conclusions for which scientific consensus was achieved. The purpose of disseminating these guidelines to the international community is based on the potential interest for other countries with similar social conditions and economical restrictions.

Antibodies, Monoclonal↗
PubMed1998

Non-cryopreserved peripheral blood stem cells autotransplants for hematological malignancies can be performed entirely on an outpatient basis.

We have prospectively performed peripheral blood stem cell autotransplants in six patients with hematological malignancies on an entirely outpatient basis. Patients were conditioned with high-dose melphalan and received a median of 4.2 x 10(8)/kg non-cryopreserved, non-purged mononuclear cells, containing a median of 3.9 x 10(6)/kg CD34 + cells. The median time to achieve > 500 granulocytes/microl was 21 days, with a range of 16 to 40, whereas the median time to achieve > 20,000 platelets/microl was 38 days, with a range of 21 to 48. Only three patients were transfused with platelets whereas packed red blood cells were transfused in two. All patients survived 60 days after the autograft and three are alive at 450, 690, and 1,950 days after the autotransplant. One patient was given an allogeneic bone marrow transplant when relapsing after the autotransplant. One patient had to be admitted to the hospital on day +10 because of fever. A median of 6,500.00 USD per patient was calculated as the total cost of each outpatient autotransplant. Since outpatient autologous transplants with non-frozen PBSC are feasible, restrictions to PBSC autotransplant programs may be overcome and costs may be diminished.

Adult↗
PubMed1998

Molecular follow-up of patients with promyelocytic leukaemia treated with all-trans retinoic acid.

Six consecutive patients with promyelocytic leukaemia displaying the PML/RAR-alpha fusion messenger ribonucleic acid (mRNA)--the molecular marker of the disease--were prospectively treated with all-trans retinoic acid: Haematological complete remission was achieved in all of them. However, in three of them the PML/RAR-alpha mRNA persisted. Subsequent treatment with ablative chemotherapy rendered the molecular remission in all cases. Two of the patients that did not achieve the molecular remission with ATRA were autografted with peripheral blood stem cells after clearing the PML/RAR-alpha fusion mRNA. One patient with tretinoin-induced molecular remission relapsed two years after diagnosis and died; the remaining five survive in complete haematological and molecular remission for periods ranging from 405 to 1695 days. Additional studies are needed to clarify the significance of the molecular follow-up of patients with PML.

Adolescent↗
PubMed1998

Tuberculosis-associated fatal hemophagocytic syndrome in a patient with lymphoma treated with fludarabine.

A patient with a stage IV high-grade non-Hodgkin's lymphoma who developed a fatal hemophagocytic syndrome is presented: When the patient had achieved complete remission and receiving fludarabine and chlorambucil/prednisone, she developed miliary tuberculosis, the CD4+ T-cell count then being 50/microL; the hemophagocytic syndrome ensuing at this point was fatal. Speculations about the predisposing factors that could have led to this complication are discussed focusing on the severe cellular immunosuppression which developed probably related to the use of fludafabine: it could be useful in the future to use anti-tuberculous prophylaxis in selected patients treated with this purine nucleoside analog.

Adult↗