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E Cuadrado

Publications and source records attributed to E Cuadrado.

At least 19 recordsLinked to original sources
PubMed2004

HLA-A*2402 and a microsatellite (D6S248) are secondary independent susceptibility markers to ankylosing spondylitis in Basque patients.

Ankylosing spondylitis (AS) is universally associated with human leukocyte antigen B27 (HLA-B27), although other genes could determine the development and clinical expression of the disease. HLA-A9 (A*2402) allele was previously found to be associated in Basque patients. The objective of this study is to perform a more precise analysis of microsatellite polymorphisms in HLA-A*2402 and B27 haplotypes to elucidate the significance of this association. A group of 50 unrelated AS patients and 113 controls of Basque origin were studied. Eight microsatellites in the class I major histocompatibility complex region with vicinity to HLA-A and -B were analyzed and the strength of allelic associations to AS and linkage disequilibrium (LD) between alleles were evaluated. Allele 15 at the microsatellite locus D6S248, 1000 Kb telomeric to HLA-A showed a strong positive association with the disease (OR:6; pc=4.7x10(-4)) and it could not be explained by LD to HLA-B27, HLA-A*2402 or any other loci. We found that D6S248-15 allele together with HLA-A*2402 could be B27-independent markers of additional susceptibility gene/s localised in the region telomeric to HLA-A in Basque AS patients.

Alleles↗
PubMed2001

HFE gene mutations analysis in Basque hereditary haemochromatosis patients and controls.

C282Y/C282Y genotype is the prevalent genotype in Hereditary Haemochromatosis (HH), however, other genotypes have been associated with the disease. The objective of our study was to analyse the frequency of the three main mutations of HFE gene in HH patients and controls from the Basque population with differential genetic characteristics. Thirty five HH patients and 116 controls were screened for C282Y, H63D and S65C mutations using a PCR-RFLP technique. The association of HLA-A and-B alleles and HFE mutations was also studied in Basque controls. The frequency of C282Y homozygotes in the group of patients was only 57%. The rest of the patients presented heterogeneous genotypes, including compound heterozygotes: 11% of them were C282Y/H63D; and 2.85% were H63D/S65C. H63D or S65C heterozygotes had a frequency of 11% and 2.85 respectively and 5.71% patients lacked any mutation The high frequency of H63D in the healthy Basque population is confirmed in this study. A considerable incidence of S65C is observed either in controls and in HH (3%) or in iron overloaded patients. The peculiar genetic characteristics of Basques could explain the heterogeneity of genotypes in HH patients of this group. Further studies should be carried out to confirm these findings although the implication of other genetic or external factors in the development of HH is suggested.

Adult↗
PubMed1999

HLA-A*9, a probable secondary susceptibility marker to ankylosing spondylitis in Basque patients.

HLA-B27 is strongly associated to ankylosing spondylitis (AS). The objective of our study was to analyze HLA-B27 association, B27 subtype distribution and frequency of other HLA class I and DR antigens in a group of Basque AS patients. HLA class I antigens were typed serologically and HLA-B27 and A9 subtypes were determined by DNA typing in samples from 46 patients with AS, 54 B27-positive spondyloarthropathies, 82 healthy subjects and 20 B27-positive controls. A class I HLA 9.2 kb PvuII restriction fragment length polymorphism (RFLP), previously associated with AS, was analyzed in a representative group of patients and controls. We found that HLA-B*2705 conferred a relative risk of 126 for AS in this group. HLA-A9 (A*2402) allele was significantly increased in AS patients compared with healthy controls and B27-positive control group (Pcorr<0.0001) and also increased in patients affected with peripheral arthritis. No association between class I HLA 9.2 Kb RFLP and AS was found. These results suggest that HLA-A*9 allele itself or another linked gene could act as a secondary and independent susceptibility allele to AS.

Alleles↗
PubMed1999

Mixed cryoglobulinaemia in patients with chronic hepatitis C infection: prevalence, significance and relationship with different viral genotypes.

In order to analyse the prevalence and significance of cryoglobulinaemia in patients with chronic hepatitis C virus (HCV) infection and the possible relationship of cryoglobulinaemia with the genotypes of HCV, we studied 89 patients with chronic HCV infection, 42 healthy controls and 22 patients with alcoholic cirrhosis. The patients with HCV were divided into three different groups according to the presence of cirrhosis and alanine aminotransferase levels. Moreover, in 20 patients with HCV and cryoglobulinaemia, HCV RNA sequences were quantified in serum and in cryoprecipitate. Cryoglobulins were detected more frequently in patients with chronic HCV infection than in healthy controls (42.6% vs. 4.7%; P<0.0001). Cryoglobulins were present in 68.4% of patients with HCV-related cirrhosis, which was nearly twice the figure in noncirrhotic HCV-infected patients and alcoholic cirrhotic patients. There were no differences in age, sex, aminotransferase levels or HCV genotype distribution in HCV-infected patients with or without cryoglobulinaemia. Only 13% of patients with chronic HCV infection and cryoglobulins showed symptoms of cryoglobulinaemia. There was a linear association between HCV RNA concentration in sera and in cryoprecipitates (P<0.0005). Patients with chronic HCV infection had a high prevalence of cryoglobulinaemia, especially in advanced forms of the disease, but clinical findings are few. There was no relationship with the genotype of HCV. The presence of HCV RNA in cryoprecipitates supported the hypothesis on the aetiological role of HCV in mixed cryoglobulinaemia.

Adult↗
PubMed1998

Bacterial translocation and T-lymphocyte populations in experimental short-bowel syndrome.

Bacterial translocation (BT) accounts in part for sepsis in short-bowel syndrome in which total parenteral nutrition (TPN) is routinely necessary. TPN "per se" facilitates BT and it has been suggested that decreased T-lymphocyte populations (TLP) in newborn rabbits and nude mice promote BT as well. We have tested the hypothesis that BT and modifications in TLP are to be expected in rats subjected to TPN and gut resection. Forty-five adult Wistar rats underwent central venous cannulations and were randomly assigned to one of three groups receiving for ten days three treatment regimes: - Group Sham (n = 17) oral intake of rat chow + saline (300 ml/kg/24 h) through a jugular vein catheter. - Group TPN (n = 17) fasting + infusion of all-in-one TPN solution (300 ml/kg/24 h). - Group RES (n = 11) fasting, same TPN regime + 80% gut resection. At the end of the experiment they were sacrified and specimens (peripheral and portal blood, spleen and mesenteric lymph nodes) were recovered, cultured and/or assessed for CD4+ and CD8+. Bacterial translocation was found in 47% of TPN animals, 92% of RES rats, but not in SHAM ones. Lymphocyte populations were not different in BT+ (n = 8) or BT- (n = 9) rats in the TPN group. TPN and resected animals showed a rise in CD4+ and a drop in CD8+ (then a better CD4+/CD8 ratio) when comparing with SHAM group rats. From this data we may conclude that: 1) BT is frequent if TPN is administered, and constant in resected animals. 2) No apparent relationship between the proportions of CD4+ and CD8+ lymphocytes and BT could be shown in TPN group. 3) High CD4+/CD8+ ratio in TPN and RES groups demonstrate that BT is possible even having good TLP.

Animals↗
PubMed1996

Immune dysfunction in Down's syndrome: primary immune deficiency or early senescence of the immune system?

Multiple immunologic disturbances are commonly observed in individuals with Down's syndrome including abnormal proportions of peripheral blood lymphoid subsets, cellular dysfunction, and autoimmune phenomena. However, a majority of the individuals with this syndrome do not show clear features of immunological disease. Many of these immunological alterations are age-related changes and can be enclosed in the spectrum of multiple signs of early senescence characteristic of Down's syndrome.

Aging↗
PubMed1995

DNA staining changes associated with apoptosis and necrosis in blood lymphocytes of individuals with HIV infection.

We used flow cytometry to quantitate cells that die by apoptosis or necrosis. The method uses low concentrations of two DNA binding dyes that allow one to establish selective regions for live, apoptotic, and necrotic cells in a rat thymocytes model. Quantitative analysis of blood lymphocyte death in individuals with HIV infection by this technique shows the presence of nonviable cells that exhibit a spectrum of changes in staining by DNA binding dyes. These changes range from typical features of cells undergoing programmed cell death or apoptosis to changes observed in cells that die by accidental death or necrosis. The proportion of cells exhibiting these lethal changes increases significantly in patients who progress to AIDS, but, although cells with staining features associated with apoptosis and necrosis were both found to be increased in in vitro-activated cells from AIDS patients, spontaneous in vivo activation preferentially leads to apoptotic changes without a significant increase of cells exhibiting the staining changes associated with necrosis.

Animals↗
PubMed1995

Lymphocyte subpopulations after extensive small bowel resection in the rat.

The increased risk of infection after massive intestinal resection (MIR) may be attributable to impaired nutrition, loss of intestinal lymphoid tissue, or both. This study examines whether MIR itself changes the immune cell populations in laboratory animals when nutritional status is preserved. The authors studied cellular immunity (lymphocyte subsets T4 and T8 and the T4:T8 ratio) and humoral immunity (IgG, IgM, IgA, and B lymphocytes) in the blood, spleen, and mesenteric lymph nodes of unresected Wistar rats (control group, n = 6) and of animals that underwent 80% bowel resection followed by 7 days of either oral feeding (resection-oral group, n = 6) or parenteral nutrition (resection-TPN group, n = 6). The increase in body weight was similar among all groups, and the levels of total protein, albumin, prealbumin, and immunoglobulin remained unchanged. All resected animals, irrespective of their feeding route, had significantly lower proportions of T4 and B lymphocytes and T4:T8 ratio in blood, T4 and T8 in mesenteric lymph nodes, and T4 and T4:T8 ratio in the spleen. The author's results suggest that removal of large amounts of lymphoid tissue along with the bowel during MIR might lead to inadequate immune response even when the nutritional status is preserved.

Animals↗
PubMed1995

The contribution of the HLA-A, -B, -C and -DR, -DQ DNA typing to the study of the origins of Spaniards and Basques.

The high polymorphism of the HLA system has been used as a powerful genetic tool to single out individuals and populations. By studying characteristic allele frequencies and extended HLA haplotypes in different populations, it is possible to identify ethnic groups and establish the genetic relationships among them. In the present study, HLA-A, -B, -C, -DR and -DQ typing at the serological/antigenic and the DNA level has been used for the first time to assign specific HLA frequencies and haplotypes to Spaniards and Basques and compare them with frequencies in other populations, particularly with North Africans. Allelic frequencies do not significantly differ between Spaniards and Basques. HLA genetic distances and their respective dendrogram together with the results on complete HLA haplotypes place Basques and Spaniards closer to paleo-North African populations than to other Europeans. This goes in favour of the Basques being a relative genetic isolate coming from the primitive Iberian/paleo-North African people. In addition, a tentative assignment of the most common Spanish HLA haplotypes to the different people who populated Iberia according to historical records has been done.

Alleles↗
PubMed1994

An immunogenetic study of familial scleroderma.

OBJECTIVE: To study the role of the HLA system in the genetic susceptibility to familial systemic sclerosis (SSc). METHODS: HLA class I antigens were determined by classic serological methods and HLA-DRB, -DQA and -DQB genes were analysed by genetic typing in 36 individuals belonging to two families with several individuals affected by SSc. RESULTS: The results did not show any association of the inheritance to SSc with any particular HLA allele in these families but revealed a striking frequency of ANA autoantibodies in healthy spouses of the members of these families. CONCLUSION: The otherwise infrequent familial incidence of SSc does not appear to be primarily linked to the HLA system in this study but it is suggested that other unknown exogenous environmental factors could be implicated in the development of the disease in families.

Adolescent↗
PubMed1993

CD8+CD38+ and CD8+DR+ peripheral blood lymphoid subsets of HIV-infected intravenous drug abusers correlate with CD4+ cell counts and proliferation to mitogens.

Twenty-nine intravenous drug abusers (ivda), with asymptomatic HIV infection at entry, were sequentially studied at 4- to 6-month intervals for variable follow-up periods (mean, 19.6 months). Two of them progressed to AIDS and another one fell into the IV-C2 stage of the CDC classification at the end of the study. CD8+ lymphoid subsets (CD57+, CD38+, and HLA-DR+) were sequentially analyzed in peripheral blood samples along the follow-up. Both absolute number and percentage of cells within these subsets were found significantly increased over those observed in normal controls. Minor changes were appreciated throughout the follow-up. CD8+CD38+ and CD8+DR+ cells increased slightly (P < 0.05), but the CD8+CD57+ subset did not change significantly. In order to determine whether abnormalities in these subsets are associated with immune dysfunction, we looked for correlation between the quantification of CD8+ subpopulations and other parameters of cellular immunity. Percentage of CD8+CD38+ or CD8+DR+ cells inversely correlates with absolute number of CD4+ cells (P < 0.0001), and percentage of CD38+ subset also correlates with the proliferative response to mitogens in lymphoid cultures. Thus, the enumeration of these populations of CD8+ cells may provide some additional information about the immune status of HIV-infected ivda.

ADP-ribosyl Cyclase↗
PubMed1993

Quantification of chicken alpha-fetoprotein: a useful tool in studies of embryo development and pathology.

Chicken alpha-fetoprotein (AFP) from the plasma of 12-day-old chick embryos was purified by electroelution from SDS/PAGE gels, and used to produce polyclonal and monoclonal antibodies. Both reagents were then used to design a sandwich-type enzyme-immunoassay for the quantification of AFP in biological fluids. The assay was used to quantify AFP in the serum and amniotic fluid of chick embryos with abnormalities of the neural tube. Serum AFP was significantly greater in these embryos than in normal ones of similar age. Moreover, substantial amounts of AFP were demonstrated in the amniotic fluid, whereas this protein was undetectable in the amniotic fluid of normal embryos. This method of assay may provide a reliable tool for studies of chick embryogenesis and abnormalities of embryonal differentiation.

Animals↗
PubMed1993

Imbalance of the CD4+ subpopulations expressing CD45RA and CD29 antigens in the peripheral blood of adults and children with Down syndrome.

Peripheral blood lymphoid subsets expressing either CD45RA or CD29 antigens, were quantified in 30 children and 59 adults with Down Syndrome and appropriate age-matched controls, by dual immunofluorescence and flow cytometry. Down's patients, both adults and children, displayed a significant decrease of CD4+CD45RA+ cells in comparison with the observed in their age-matched controls, but no difference was found in the CD4+CD29+ subset. These results show clearly the imbalance of these subpopulations in the peripheral blood of individuals with Down syndrome that result in the inversion of the CD45RA/CD29 ratio, due to a major reduction of the CD45RA subset. No obvious difference was found in the CD45RA/CD29 ratio within the CD4 negative cells. Abnormalities of these subpopulations could be indicative of early senescence of the immune system, since age-related changes in Down's persons were in parallel with those observed in normal individuals and the proportion of both subpopulations were roughly similar in Down's children and normal adults.

Adolescent↗
PubMed1993

[Amniotic and serum alphafetoprotein in the chick embryo with neural tube defect].

Although alpha-feto-protein (AFP) is a widely used marker for human neural tube defects (NTD) little is known about the mechanisms for its increase in the amniotic fluid in this condition. For investigating this issue we developed a chick embryo AFP assay and tested it in a NTD experimental model. AFP obtained by electroelution on PAGE/SDS gels from the plasma of 12-day-old embryos was used to produce rabbit polyclonal and mouse monoclonal antibodies. A specific sandwich-type enzyme-immune-assay was developed using both reagents. Sterile aspiration of 5 ml. of albumen from 602 fertile hen eggs on the 27th hour of incubation (Hamburger stages 8 to 11) led to the appearance of NTD in 36 out of the 270 survivors (13%). Amniotic and seric AFP levels were measured on the 15th day of incubation in NTD chicks (n = 11) and in control ones (n = 9) and the results were compared by non-parametric tests. Serum AFP was five times higher in NTD chicks than in controls (119.2 +/- 32.6 vs 523.3 +/- 173.62 micrograms/ml., p < 0.001) and amniotic AFP was absent in control and very increased in NTD animals (0.15 +/- 0.02 vs 87.14 +/- 84 micrograms/ml., p < 0.001). It is concluded that: 1) serum AFP is intriguingly increased in the chick with NTD; 2) since urine is not diversed into the amniotic sac in the avian embryo, the only source of AFP in its fluid is exudation through an open defect. This conclusion is further supported by the absence of amniotic AFP in a chick with a large closed NTD.

Amniotic Fluid↗
PubMed1993

[The defense against infection in the short bowel syndrome].

The high risk of infection in the short-bowel syndrome (SBS) may be due to malnutrition, lost of lymphoid bowel structures or both. Total parenteral nutrition (TPN) may alleviate the malnutrition, but we do not know what will happen with immune response in SBS with good nutritional state. We have studied the cellular immunity (lymphocytic subsets T4 and T8 and T4/T8 ratio) and the humoral one (IgG, IgM, IgA and B lymphocytes) in blood, spleen and mesenteric lymph nodes, in 12 wistar rats with 80% bowel resection, 6 of them with oral feeding and 6 with TPN, and 6 control rats, during 7 days. The weight increased and the total protein, albumin and prealbumin levels were the same in all groups. There was not difference between the resected groups. No difference was observed in the rate of immunoglobulins and the resected groups showed significatively lower figures than the control group in T4, B lymphocytes and T4/T8 ratio in blood, T4 and T8 in mesenteric nodes and in T4 and T4/T8 ratio in the spleen. These results suggest that the resection of large amounts of bowel could produce a fall in the immune response even when adequate nutritional state is preserved.

Animals↗
PubMed1992

Differential expression of lymphocyte function-associated antigen (LFA-1) on peripheral blood leucocytes from individuals with Down's syndrome.

We analysed the expression of lymphocyte function-associated antigen LFA-1 on the cell surface of peripheral blood lymphocytes, monocytes and granulocytes from 20 children with Down's syndrome. No differences in LFA-1 expression was found within monocytes or granulocytes from either normal or Down's syndrome children; however, a clear-cut difference was observed on lymphoid cells. Both normal and Down's syndrome lymphocytes displayed a bimodal pattern of LFA-1 staining by flow cytometry, with a predominance of cells with low expression in normal population, and an increased proportion of lymphocytes with high level of LFA-1 expression in Down's syndrome children. This difference correlates well with the abnormal proportion of T cell subsets and inversion of CD4/CD8 observed in a majority of our cases, and therefore, it could merely reflect the increase of certain T cell subsets normally expressing higher number of LFA-1 molecules. Taken together, our results do not support an abnormally increased expression of leucocytes integrins in trisomy 21 cells, and raise some doubt about the suggested role of the abnormal cellular expression of LFA-1 in the pathogensis of secondary immunodeficiency associated to Down's syndrome.

Antigens, CD↗