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P Chardon

Publications and source records attributed to P Chardon.

At least 55 records · Page 3Linked to original sources
PubMed1998

Porcine major histocompatibility complex.

The major histocompatibility complex in swine (swine leucocyte antigen: SLA) is located on chromosome 7 with the class I and class III regions separated by the centromere from the class II region. The overall molecular organisation of the class I and III regions is well known, but further research is needed to establish that of the class II region. Approximately sixty genes have been characterised to date, including ten tightly packed SLA class I sequences. The exact number of functional polymorphic class I genes, as defined by serology, probably varies from one to four, depending on the haplotype. At least two other distantly class I-related gene families exist. The numerous and significant associations reported between SLA haplotypes and physiological traits are described. These traits include immune responsiveness to a variety of microbes and metazoan parasites, and male and female production and reproduction performance. The results obtained suggest that selection for specific SLA haplotypes may assist in the improvement of porcine production.

Animals↗
PubMed1997

Construction of a swine YAC library allowing an efficient recovery of unique and centromeric repeated sequences.

A swine DNA genomic library was constructed in yeast artificial chromosome (YAC) using the pYAC4 vector and the AB1380 strain. The DNA prepared from two Large White males was partially digested with EcoRI and size selected after both digestion and ligation. The YAC library contained 33792 arrayed clones with an average size of 280 kb as estimated by analysis of 2% of the clones, thus representing a threefold coverage of the swine haploid genome. The library was organized in pools to facilitate the PCR screening. The complexity of the library was tested both for unique and centromeric repeated sequences. In all, 20 out of 22 primer sets allowed the characterization of one to six clones containing specific unique sequences. These sequences are known to be on Chromosomes (Chrs) 1, 2, 5, 6, 7, 8, 13, 14, 15, 17, and X. Eight additional clones carrying centromeric repeat units were also isolated with a single primer set. The sequencing of 37 distinct repeat units of about 340 bp subcloned from these eight YACs revealed high sequence diversity indicating the existence of numerous centromeric repeat unit subfamilies in swine. Furthermore, the analysis of the restriction patterns with selected enzymes suggested a higher order organization of the repeat units. According to preliminary FISH experiments on a small number of randomly chosen YACs and YACs carrying specific sequences, the chimerism appeared to be low. In addition, primed in situ labeling experiments favored the idea that the YACs with centromeric repeat sequences were derived from a subset of metacentric and submetacentric chromosomes.

Animals↗
PubMed1997

Swine centromeric DNA repeats revealed by primed in situ (PRINS) labeling.

In swine, distinct centromeric satellite DNA families have been described that correspond to either all the metacentric chromosomes except the Y (Mc1) or all the acrocentric chromosomes (Ac2). Using primed in situ (PRINS) labeling, we show here that primers derived from various sequences specifically label the centromeres of different subgroups of chromosomes. Among five primers derived from centromeric sequences of acrocentric chromosomes reported to be very homogeneous, four recognize all the acrocentric chromosomes, whereas one labels prominently chromosome 17. For the metacentric chromosomes, six primers have been derived from several divergent sequences. Among these primers, two recognize all the metacentric chromosomes except 5, 10, and 12. Three other primers label small subsets of metacentric chromosomes, including the X and one or two additional chromosomes. The last primer is specific to chromosome 1. These preliminary results suggest that it should be possible to define specific primers for almost every swine chromosome. Already, some of the primers reported here permit a distinction between swine chromosomes difficult to differentiate without banding, such as the X chromosome and chromosome 9. Therefore, the PRINS technique using centromeric motifs constitutes an additional tool for cytogenetic studies in swine.

Animals↗
PubMed1996

A detailed physical map of the porcine major histocompatibility complex (MHC) class III region: comparison with human and mouse MHC class III regions.

A detailed physical map of the porcine MHC class III region on Chr 7 was constructed with a panel of probes in a series of hybridizations on genomic pulsed field gel electrophoresis (PFGE) Southern blots. A precise organization of the 700-kb segment of DNA between G18 and BAT1 can now be proposed, with more than 30 genes mapped to it. Comparison of this region with homologous regions in human and mouse showed only minor differences. The biggest difference was observed in the CYP21/C4 locus with only one CYP21 gene and one C4 gene found, whereas in human and mouse these genes are duplicated. These results show the class III region is very well conserved between pig, human, and mouse, in contrast with the class I and class II regions, which seem more prone to rearrangements.

Animals↗
PubMed1995

The BAT1 gene in the MHC encodes an evolutionarily conserved putative nuclear RNA helicase of the DEAD family.

The BAT1 gene has previously been identified about 30 kb upstream from the tumor necrosis factor (TNF) locus and close to a NF kappa b-related gene of the nuclear factor family in the major histocompatibility complex (MHC) of human, mouse, and pig. We now show that the BAT1 translation product is the homolog of the rat p47 nuclear protein, the WM6 Drosophila gene product, and probably also Ce08102 of Caenorhabditis elegans, all members of the DEAD protein family of ATP-dependent RNA helicases. This family has more than 40 members, including the eukaryotic translation initiation factor-4A (eIF-4A), the human nuclear protein p68, and the Drosophila oocyte polar granule component vasa. BAT1 spans about 10 kb, is split into 10 exons of varying length, and encodes a protein of 428 amino acids (approximately 48 kDa). Human and pig BAT1 cDNAs display 95.6% identity in the coding region and 80% identity in the 5' and 3' noncoding regions. Several repeat sequences of different types were identified in introns of the porcine BAT1 gene. Three different mRNAs, 4.1, 1.7, and 0.9 kb, respectively, were detected in all tissues analyzed upon hybridization with porcine BAT1 cDNA. Transfection and expression of human BAT1 cDNA after tagging with a heterologous antibody recognition epitope revealed a nuclear localization of the hybrid protein. An MspI RFLP was detected in an SLA class I typed family, confirming the localization of the BAT1 gene in the porcine MHC. BAT1 thus encodes a putative nuclear ATP-dependent RNA helicase and is likely to have an indispensable function.

Amino Acid Sequence↗
PubMed1994

Characterization of six new loci within the swine major histocompatibility complex class III region.

A search for new potential coding sequences was conducted within two overlapping cosmid genomic DNA clusters of about 170 and 45 kb from the swine major histocompatibility complex class III region. The sequences were detected with various probes, including pools of swine cDNA, homologous and heterologous genomic sequences, and synthetic oligonucleotides. The 170 kb cluster was centered on the tumor necrosis factor genes (TNF), and the 45 kb cluster contained the heat-shock protein 70 genes (HSP70). The TNF cluster revealed the presence of five new genes: lymphotoxin beta, BAT1, BAT2, BAT3, and a sequence related to DNA-binding factors. No sequence homologous to B144 was found in the TNF cluster, although other unidentified coding sequences may be present in this cluster. The HSP70 cluster contained a gene identified as BAT6, that is, tRNA-valyl synthetase. These results provide new evidence that the genomic maps of these various genes in the TNF and HSP70 sub-regions are similar in swine and human.

Animals↗
PubMed1993

Characterization of a polymorphic heat shock protein 70 gene in swine outside the SLA major histocompatibility complex.

To characterize a hitherto unidentified swine Hsp70 gene, a cDNA library was prepared from total RNA isolated from swine lymphocytes and heat-shocked at 42 degrees C for 2 h. One positive clone with a 2.6 kb insert was found. Its sequencing revealed a maximum homology with the human inducible Hsp70B' gene. The genomic polymorphism of this insert was investigated by restriction fragment length polymorphism (RFLP) in an informative family for the major histocompatibility complex SLA. Digestion with PvuII generated 8 bands which were common to both parents, and for the male two extra bands at 0.69 and 0.64 kb. After digestion with PstI, there was also an extra band at 1.6 kb for the male in addition to the seven bands common to both parents. The eleven offsprings' RFLP patterns exhibited all the common parental bands, but four piglets displayed the male's specific bands in addition. All the polymorphic bands belonged to the same locus and segregated independently of SLA. Restriction mapping of the Hsp70 gene indicated the absence of introns, and showed that the polymorphic PstI site was located upstream of the gene's 5' coding region, and the PvuII site inside its coding region.

Amino Acid Sequence↗
PubMed1993

Isolation of four HSP70 genes in the pig and localization on chromosomes 7 and 14.

For insight into the general organization of the swine leukocyte antigen (SLA) complex, the swine major histocompatibility complex (MHC), four sequences related to the heat-shock proteins HSP70 were characterized by screening of a pig genomic cosmid library with a swine cDNA HSP70 2.6-kb probe. This yielded three positive clones: HC2.2, HC3.2, and HC4.2. Restriction site maps revealed a large overlap of HC2.2 with HC3.2, whereas HC4.2 was independent. Southern blot hybridization with the 5' section, the central section, and the 3' section of the 2.6-kb probe and also with a swine 4.5-kb HSP70 genomic probe suggested the existence, within the overlapping clones, of three distinct HSP70 sequences encompassing a segment no longer than 22 kb. The HC4.2 clone, which hybridized with the same probes, displayed a single band of 7.3 kb, probably corresponding to one gene only. Fluorescent in situ hybridization on swine chromosome metaphases with the whole HC2.2 or HC4.2 cosmids allowed the assignment of HC2.2 to MHC region on Chromosome (Chr) 7 (Cen-p1.1), and of HC4.2 to Chr 14 (q2.4-2.5). Thus, as in humans, the swine MHC comprises three closely linked HSP70 loci. The presence of additional genes belonging to the same inducible HSP70 gene family can be expected from what is known in humans. The HSP70 gene found here on the pig Chr 14 may be one of these putative unidentified genes.

Animals↗
PubMed1992

[Sedation with propofol and fentanyl in patients under intensive care].

This study investigated the efficacy of a constant rate infusion of propofol and fentanyl in thirty patients requiring artificial ventilation for more than 24 h. A loading dose, which differed according to the patient's age, was administered over a 30 min period: 2.5 mg.kg-1 for patients less than 50 (G1) (n = 9), 2 mg.kg-1 for patients between 50 and 60 years old (G2) (n = 9), and 1.5 mg.kg-1 for patients over 60 (G3) (n = 12). This was followed by an infusion of 3 mg.kg-1.h-1 in G1 and G2, and 2 mg.kg-1.h-1 in G3. A 1 microgram.kg-1.h-1 infusion of fentanyl was also given. The degree of sedation was assessed with the Ramsay scale before starting, after induction, and every four hours thereafter. When this proved to be insufficient, the dose of propofol was increased by 0.5 mg.kg-1.h-1 as well as that of fentanyl by 0.5 microgram.kg-1.h-1. Heart rate, mean arterial blood pressure, blood propofol, creatinine, transaminase and lipid levels, and urine output were measured before, during, and after the infusion. The blood propofol level increased during the infusion, being correlated to the doses given (r = 0.64, p less than 0.001). Sedation lasted 91.7 +/- 57.7 h. After stopping the infusion of propofol, mean recovery times were 7.5 +/- 5.9 min (G1), 11.4 +/- 11.4 min, and 14.4 +/- 13.5 min (G3) (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Pig standard bivariate flow karyotype and peak assignment for chromosomes X, Y, 3, and 7.

A standard pig flow karyotype (2N = 38 chromosomes) was defined by standardization of several flow karyotypes obtained from stimulated peripheral blood lymphocytes of normal male and female pigs. Depending on the animals under study, the flow analysis of their chromosome suspensions gave rise to bivariate flow karyotypes comprising from 15 to 17 peaks, of which 11 to 15 represented single chromosomes. The results were used to propose a peak nomenclature. In addition, a male miniature pig lymphoblastoid cell line was characterized by flow cytogenetics. A very high-resolution flow karyotype, in which all peaks but one superimposed on those of the standard karyotype, was obtained. Peaks were assigned for chromosomes X and Y. Analysis of flow karyotypes obtained from translocated t(3,7)(p1.3;q2.1) pigs combined with polymerase chain reaction (PCR) studies of major histocompatibility complex (MHC)-linked sequences on flow-sorted chromosomes allowed identification of peaks 3 and 7 of normal pig chromosomes and of the derivative chromosomes associated with the t(3,7)(p1.3;q2.1) translocation.

Animals↗
PubMed1991

Marked genetic polymorphism of the swine steroid 21-hydroxylase gene, and its location between the SLA class I and class II regions.

Restriction fragment length polymorphism (RFLP) analysis of the swine 21-hydroxylase (CYP21) region was conducted on 31 unrelated SLA class I typed pigs, mainly Large Whites, including 15 haplotypes. Ten haplotypes were from SLA genotypic homozygotes and five were from SLA class I phenotypic homozygotes. DNA digestion with Hin dIII, TaqI and PstI, and hybridization to a 4.5-kb swine CYP21 genomic probe yielded respectively two, four and three RFLP patterns. Six patterns were identified with combined RFLP. In addition, analysis of the CYP21 region in families comprising several SLA recombinants demonstrated that the CYP21 gene lies in the DNA segment between the SLA class I and class II regions. These overall results reinforce our previous conclusion about the existence in the pig of a single 21-hydroxylase gene. The characterization of at least six CYP21 allelic patterns provides a new tool for studying the associations between the SLA region and zootechnical traits.

Alleles↗
PubMed1990

The swine steroid 21-hydroxylase gene (CYP21): cloning and mapping within the swine leucocyte antigen complex.

A swine genomic cosmid library constructed from a genotypically SLA homozygous Large White individual was screened with a murine genomic 21-hydroxylase probe. A clone which contained a pig 21-hydroxylase gene was isolated and after subcloning, the 5' region of the gene was sequenced. The deduced amino acid sequence corresponded almost exactly to the NH2 terminal portion of the steroid 21-hydroxylase from porcine adrenal microsomes. Comparison of the first 99 amino acid residues of both sequences revealed three substitutions comprising two leucine residues in positions 10 and 13, and one arginine residue in position 55 for our sequence, instead of threonine in position 10 and lysine in position 13 and 55 for the isolated enzyme. A swine homologous probe was derived from the isolated 21-hydroxylase gene and used for gene assignment by RFLP studies in two swine leucocyte antigen (SLA) informative families. The results demonstrate that the swine 21-hydroxylase gene is located within or close to the swine MHC. Taken together, the present results suggest the existence of a single 21-hydroxylase gene per haploid genome.

Animals↗
PubMed1987

Molecular genetic analysis of the major histocompatibility complex in an ELA typed horse family.

Restriction fragment length polymorphism was studied in an ELA typed horse family which included a stallion, a mare with two full-sibs, another mare with three full-sibs and, in addition, three paternal half-sibs. DNA samples from all individuals were investigated by Southern blot analysis using three restriction enzymes (EcoRI, HindIII or TaqI) and human cDNA class I, class II (DR beta) and class III (C4) probes. In addition, a genomic class II DQ alpha probe was used. Fragments hybridized with the various probes revealed the existence of DNA sequences homologous to HLA class I, DR beta, DQ alpha and C4 genes in the horse. Polymorphic fragments were found when DNA was hybridized with class I and class II probes irrespective of the enzyme used; but hybridization with the C4 probe did not reveal variability. All polymorphic fragments segregated according to the ELA serological specificities, thus indicating a close linkage between the different revealed subregions. Banding patterns suggest that the horse possesses about 20-30 class I genes, probably more than one DR beta and DQ alpha genes and possibly only one C4 gene. The high degree of polymorphism observed suggests that molecular DNA typing may represent a potentially powerful aid to decision in parentage control determination.

Animals↗