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F Setién

Publications and source records attributed to F Setién.

At least 19 recordsLinked to original sources
PubMed2001

Characterization of the MHC class I-related MR1 locus in nonhuman primates.

We characterized the MHC-related 1 ( MR1) locus in two nonhuman primates species, Pongo pygmaeus and Pan troglodytes. MR1 cDNA sequences encoding several isoforms generated through alternative splicing were observed in both species. Amino acid alignment between the five species in which MR1 has been characterized to date - human, chimpanzee, orangutan, mouse, and rat - reveals a very high degree of conservation specially in the alpha1 and alpha2 domains of the molecule. The main differences concentrate in the transmembrane and cytoplasmic domains. In the three primates species there is a lysine residue inside the putative transmembrane domain which is not present in rodents. Furthermore, the MR1 cytoplasmic region is longer in rodents, with a conserved serine-containing motif that could be involved in endocytosis; remarkably, this motif is absent in the three primate species. We also describe the presence in the chimpanzee of a sequence homologous to the MR1P1 pseudogene previously found in humans.

Amino Acid Sequence↗
PubMed2001

Structural characterization of two CD1A allelic variants.

CD1 molecules are specialized in presenting lipidic antigens to T lymphocytes. They are structurally and evolutionary related to MHC molecules and show very limited polymorphism. We have previously described and partially characterized a new human CD1A allele differing from the wild type CD1A by a substitution of Cysteine by Tryptophan at position 52 in the alpha1 domain of the CD1A molecule. The frequency of this allele varies from 10% in individuals of Caucasian origin to 56% in Chinese people. The aim of the present work was to structurally characterize this CD1A allele. To do this we have cloned and sequenced the full-length cDNA encoding the new CD1A allele. The cDNA sequence of this allele encodes a protein differing the wild type in two amino acids at positions 14 (Threonine versus Isoleucine) and 52 (Cysteine versus Tryptophan). The cDNAs encoding both wild type and mutant CD1A were cloned in the expression vector pSRalphaNeo and transfected into C1R and L721.221 cells. Cell surface expression of the protein products in transfected cell lines were analyzed by flow cytometry and immunoprecipitation using CD1a-specific monoclonal antibodies. Our results indicate that both allelic products are efficiently expressed on the cell surface.

Alleles↗
PubMed2000

A study on the polymorphism of human MHC class I-related MR1 gene and identification of an MR1-like pseudogene.

Human MR1 is a recently discovered, ubiquitously transcribed gene very similar to the HLA class I loci and of unknown function. Mouse and rat MR1 sequences have also been described showing high similarity with the human gene. The goal of this work was to investigate if human MR1 was polymorphic. We have found that DNA sequences of MR1-specific polymerase chain reaction (PCR) products obtained from samples of diverse ethnic origin were invariant except in one case in which two silent mutations were detected. We also found an MR1-like sequence displaying significant differences with the previously described, the most remarkable of which is a STOP codon in the alpha2 domain indicating that is a pseudogene.

Base Sequence↗
PubMed1999

Single strand conformational polymorphism analysis of human CD1 genes in different ethnic groups.

CD1 molecules are able to present unusual antigens, lipids or glycolipids from mycobacterium cell walls to T lymphocytes. Previous studies have suggested that polymorphism of these genes is very limited, in contrast with classical major histocompatibility complex (MHC) antigen-presenting molecules. Our aim was to study possible allelic variations of exons 2 and 3, encoding for the alpha1 and alpha2 domains, respectively, of human CD1A, -B, -C and -D genes. We analyzed genomic samples of unrelated, healthy individuals from different ethnic background: 70 Caucasians from Europe, 33 Black Africans (13 from Tanzania and 20 Zulus), 19 Caucasians from the Sahara and 44 Asian individuals. We have found CD1A to be a biallelic locus with a common allele which was present in the majority of the individuals studied. The second allele differed from the common one by a single-point mutation, resulting in a change of Cys to Trp at position 52 in the alpha1 domain. This second allele was found in heterozygosis in 7 out of 70 Caucasians from Europe (allelic frequencies P=0.95 and q=0.05). In the Chinese population, we found the second allele present in heterozygosis in 19 from the 44 individuals studied, and we also found 6 homozygous individuals for the second allele (allelic frequencies P=0.64 and q=0.35). In addition, we detected a synonymous mutation (C to T transition) in codon 34 of CD1C exon 2 in 4 out of 20 Zulus and in 2 of the 13 Blacks from Tanzania.

Africa↗
PubMed1996

Characterization of interleukin-8 receptors in non-human primates.

Interleukin-8 is a chemokine with a potent neutrophil chemoattractant activity. In humans, two different cDNAs encoding human IL8 receptors designated IL8RA and IL8RB have been cloned. IL8RA binds IL8, while IL8RB binds IL8 as well as other alpha-chemokines. Both human IL8Rs are encoded by two genes physically linked on chromosome 2. The IL8RA and IL8RB genes have open reading frames (ORF) lacking introns. By direct sequencing of the polymerase chain reaction products, we sequenced the IL8R genes of cell lines from four non-human primates: chimpanzee, gorilla, orangutan, and macaca. The IL8RB encodes an ORF in the four non-human primates, showing 95% - 99% similarity to the human IL8RB sequence. The IL8RA homologue in gorilla and chimpanzee consisted of two ORF 98% - 99% identical to the human sequence. The macaca and orangutan IL8RA homologues are pseudogenes: a 2 base pair insertion generated a sequence with several stop codons. In addition, we describe the physical linkage of these genes in the four non-human primates and discuss the evolutionary implications of these findings.

Amino Acid Sequence↗
PubMed1996

Molecular evolution of the N-formyl peptide and C5a receptors in non-human primates.

N-formyl peptides (FMLP) and complement fragment C5a are neutrophil chemoattractants. In humans, a single-copy gene was identified for the C5a receptor, and the receptor for FMLP (FPR1) is encoded by a single gene that shows 53% amino acid similarity to the C5aR. Two other human FPR1 homologues, FPR-like 1 (FPR2/FPRL1) and FPR-like 2 (FPRL2) have been cloned. The human C5aR, FPR1, FPRL1, and FPRL2 are physically linked. By direct sequencing or by sequencing plasmid clones we studied the C5aR and FPR genes from four non-human primates (chimpanzee, gorilla, orangutan, and macaque). The sequences showed 95% - 99% similarity to the human homologues, with the major divergences observed in macaque. In these genes, the transmembrane and the cytoplasmic domains are highly conserved, while the highest divergence corresponded to the extracellular loops involved in ligand binding. Additionally, we constructed a physical map of these genes in non-human primates. In all species the four genes were physically linked and we defined the relative orientation of the four genes in primates: C5aR>FPR1>FPR2 (FPRL1)>FPRL2.

Amino Acid Sequence↗
PubMed1995

Genetic detection of the silent allele (*Q0) in hereditary deficiencies of the human complement C6, C7, and C9 components.

DNA polymorphisms (RFLPs) of the human complement component C6, C7, and C9 genes were studied in three C7-deficient (C7D) families, one C6-deficient (C6D) family, and one C9-deficient (C9D) family. The 3 loci are closely linked on human chromosome 5. The haplotypes carrying the "silent" allele (C7*Q0, C6*Q0, and C9*Q0) were defined in each family, allowing for the detection of carriers among asymptomatic relatives. This paper describes familial studies on a type of hereditary trait, characterized by recurrent Neisseria infections in individuals homozygous for "silent" alleles at the C6, C7, or C9 loci.

Alleles↗
PubMed1995

HLA-B27 subtypes in Asian patients with ankylosing spondylitis. Evidence for new associations.

The aim of this study was to investigate the contribution of the different B27 subtypes to ankylosing spondylitis (AS) susceptibility. The polymerase chain reaction (PCR) in combination with the sequence-specific oligonucleotide probes (SSOs) was used to analyse the polymorphism in exon 2 and 3 of HLA-B27 in two Asian groups with different genetic HLA structures: Indian (I) and Thai (T) populations. The same number of AS patients (45) and healthy B27 positive donors (n = 17) from both populations were analysed in order to ascertain the B27 subtypes. Three different findings can be concluded from this study: 1) B*2707 has been found to be associated with AS in both populations. This association has not been previously reported in either ethnic group. 2) B*2704 is strongly associated with AS in the Thai patients (91% in AS vs. 47% in C; RR = 11.5; EF = 0.83). In contrast, B*2704 was found with similar frequency in Asian Indians AS patients and controls (41% in AS vs. 41% in C.). 3) B*2706 was found overrepresented in control populations and absent in AS patients (0% in AS vs. 47% in C.; pc < 10(-6)) showing the maximum value of protective fraction (PF = 1). The B*2706 negative association with AS has not been previously described in other ethnic groups and could indicate a protective effect of this subtype on AS susceptibility. The B*2706 allele has two changes relative to B*2704 at residue 114 (His to Asp) and 116 (Asp to Tyr) in the pockets D/E. The importance that these differences can play in the pathogenesis of AS are discussed.

Amino Acid Sequence↗
PubMed1994

A physical map of two clusters containing the genes for six proinflammatory receptors.

The genes encoding for six receptors involved in the proinflammatory response lie on different chromosomes. Two receptors for N-formylpeptides (FPR1, FPR2), one homologue of these (FPRL2), and the receptor for complement fragment C5a (C5aR) are encoded by four genes mapped to human chromosome 19. The genes encoding two receptors for Interleukin-8 (IL8RA, IL8RB) have been located on human chromosome 2. In this report we describe the physical linkage between these genes in two different clusters. DNA fragments obtained by digestion with several restriction enzymes were separated by pulsed field gel electrophoresis. Nylon filters were hybridized with probes corresponding to the complete translated sequences of these genes. These probes were obtained from a human neutrophil cDNA-library. The four genes on chromosome 19 are contained in a 200 kilobase (kb) fragment. Both Interleukin-8 receptors are on a 150 kb fragment. The complete translated sequences for these genes were amplified from genomic DNA, indicating that they are contained in a single exon.

Base Sequence↗
PubMed1994

Combined (short-term plus longterm) sclerotherapy v short-term only sclerotherapy: a randomised prospective trial.

Short term sclerotherapy (by injection(s) around the bleeding point) is used for immediate control of massive haemorrhage from oesophagogastric varices. The usefulness of longterm sclerotherapy once short term sclerotherapy has been successfully carried out was assessed. Two treatment groups were studied: 50 patients were treated by 'combined' (short term followed by longterm) sclerotherapy; 56 patients were treated by short term sclerotherapy only. Patients included in the second group were treated by short term sclerotherapy only if a variceal rebleeding was present. The overall cumulative proportion of patients rebleeding was not significantly different in either group. Combined sclerotherapy patients, however, experienced less episodes of variceal haemorrhage and the source of haemorrhage was different (p < 0.002). Combined sclerotherapy was more efficient in preventing bleeding from oesophageal bleeding points but not those arising from a junctional source (p < 0.05). A greater incidence of oesophageal rebleeding was found in those patients whose first source of bleeding was oesophageal (p < 0.05). No significant difference was detected in survival expectancy between either group. In conclusion, after short term sclerotherapy is carried out successfully, those patients with bleeding from variceal bleeding points located on oesophageal mucosa should benefit most from a longterm sclerotherapy programme.

Esophageal and Gastric Varices↗
PubMed1993

A physical map of the human complement component C6, C7, and C9 genes.

The genes for human complement components C6, C7, and C9 are linked on chromosome 5. In this report we describe the physical linkage between C6 and C7 genes. DNA fragments obtained by digestion with several rare-cutting restriction enzymes were separated through pulsed field gel electrophoresis. Hybridization with probes corresponding to the 5' and 3' ends of the three cDNAs showed common bands for the C6 and C7 genes. Both genes are contained in a NotI fragment of 500 kilobases (kb). Moreover, the presence of common 3' C6 and 3' C7 fragments indicates that both genes are oriented in a tail-to-tail, reverse way relative to transcription. No evidence of physical linkage between C9 and C6 or C7 was found in the range 50 kb-2.5 megabases (Mb).

Chromosome Mapping↗
PubMed1991

Germline repertoire of T-cell receptor beta-chain genes in patients with insulin-dependent diabetes mellitus.

We have investigated the genotype and allelic distribution of germline restriction fragment length polymorphisms of the T-cell receptor beta chain, segment C beta, and two variable segments which are in linkage disequilibrium, V beta 8 and V beta 11, in 42 insulin-dependent diabetes mellitus (IDDM) patients and in 51 healthy blood donors used as controls. Recently, several works have reported contradictory results showing or not showing an association between polymorphic alleles of the C beta gene and diabetes type I. We found no significant differences in the allele, genotype, and haplotype distribution of the gene segments studied, between IDDM patients and control populations.

Adolescent↗
PubMed1987

Efficacy of monopolar electrocoagulation in the treatment of bleeding gastric ulcer: a controlled trial.

With the aim of evaluating, in a controlled prospective fashion, the efficacy of monopolar electrocoagulation in the emergency treatment of bleeding gastric and stomal ulcers, 37 patients were studied: 16 were electrocoagulated (EC group) while the remaining 21 were treated by conventional methods (control group). The hemorrhage recurred in only one of the 16 patients belonging to the EC group, but in 11 of the 21 control patients (p less than 0.0005). Transfusion requirements were also reduced in the EC group (p less than 0.05), with no significant difference in relation to mortality. Stratifying the results according to hemorrhagic activity, electrocoagulation should be clearly effective in those patients with spurting hemorrhage, taking into account several limitations: deep ulcers bearing gross vessels, and lack of cooperation by the patient. Prophylactic treatment of the bleeding ulcer with a visible non-spurting vessel may be indicated whenever we make a proper selection of the patients with a greater possibility of hemorrhagic recurrence.

Adult↗