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R Fries

Publications and source records attributed to R Fries.

At least 55 records · Page 3Linked to original sources
PubMed2001

Assessment of the nucleotide sequence variability in the bovine T-cell receptor alpha delta joining gene region.

The sequence of 2,193 nucleotides from the bovine T-cell receptor alpha/delta joining gene region (TCRADJ) was determined and compared with the corresponding human and murine sequences. The identity was 75.3% for the comparison of the Bos taurus vs. the Homo sapiens sequence and 63.8% for the Bos taurus vs. the Mus musculus sequence. This comparison permitted the identification of the putatively functional elements within the bovine sequence. Direct sequencing of 2,110 nucleotides in nine animals revealed 12 variable sites. Estimates, based on direct sequencing in three Holstein Friesian animals, for the two measures of sequence variability, nucleotide polymorphism (u) and nucleotide diversity (p), were 0.00050 (60.00036) and 0.00077 (60.00056), respectively. The test statistic, Tajima's D, for the comparison of the two measures indicates that the difference between u and p is close to significance (P < 0.05), suggesting the possibility of selective forces acting on the studied genomic region. Allelic variation at 5 of the 12 variable sites was analysed in 359 animals (48 Anatolian Black, 56 Braunvieh, 115 Fleckvieh, 47 Holstein Friesian, 50 Simmental and 43 Pinzgauer) using the oligonucleotide ligation assay (OLA) in combination with the enzyme linked immunoabsorbant assay (ELISA). Nine unambiguous haplotypes could be derived based on animals with a maximum of one heterozygous site. Four to seven haplotypes were present in the different breeds. When taking into account the frequencies of the haplotypes in the different breeds, especially in Anatolian Black, an ancestral cattle population, we could establish the likely phylogenetic relationships of the haplotypes. Such haplotype trees are the basis for cladistic candidate gene analysis. Our study demonstrates that the systematic search of single nucleotide polymorphisms (SNPs) is useful for analysing all aspects of variability of a given genomic region.

Alleles↗
PubMed2000

A DNA polymorphism influencing alpha(1,2)fucosyltransferase activity of the pig FUT1 enzyme determines susceptibility of small intestinal epithelium to Escherichia coli F18 adhesion.

The alpha(1,2)fucosyltransferases (FUT1 and FUT2) contribute to the formation of blood group antigen structures, which are present on cell membranes and in secretions. In the present study we demonstrate that both FUT1 and FUT2 are expressed in the pig small intestine. FUT1 polymorphisms influence adhesion of F18 fimbriated Escherichia coli (ECF18) to intestinal mucosa, and FUT2 is associated with expression of erythrocyte antigen 0. The FUT1 polymorphisms result in amino acid substitutions at positions 103 (Ala-->Thr) and 286 (Arg-->Glu). Tightly controlled expression of the FUT2 gene results in either an abundance or an absence of mRNA in small intestinal mucosa. ECF18-resistant animals were shown to be homozygous for threonine at amino acid 103 of the FUT1 enzyme. Susceptibility to ECF18 adhesion appeared to be solely dependent on the activity of FUT1 in intestinal epithelia. In intestinal mucosae of ECF18-resistant pigs which expressed FUT1 but not FUT2 RNA, the levels of alpha(1,2)fucosyltransferase activity were significantly lower (28- to 45-fold, P<0.001) than in susceptible pigs. Moreover, lysates of CHO cells transfected with FUT1 constructs encoding threonine at amino acid position 103 also showed significantly reduced enzyme activity compared with constructs encoding alanine at this position. Our genetic and enzymatic studies support the hypothesis that the FUT1 enzyme, and particularly the amino acid at position 103, is likely important in the synthesis of a structure that enables adhesion of ECF18 bacteria to small intestinal mucosa.

Animals↗
PubMed2000

[Reconstruction of the bicuspid aortic valve].

Reconstruction of a regurgitant bicuspid aortic valve is a new alternative to aortic valve replacement. With concomitant aortic root dilatation adequate reconstruction is feasible by valve-sparing aortic replacement. Between 10/95 and 02/00, 30 patients underwent reconstruction of a regurgitant bicuspid aortic valve. Additional aortic replacement was performed in 23 cases. Valve reconstruction was performed by plication of the prolapsing leaflet. No patient died peri- or postoperatively. Freedom from aortic valve regurgitation > or = II as well as freedom from reoperation were 100% after 48 months. Reconstruction of a regurgitant bicuspid aortic valve is feasible with encouraging mid-term results. With concomitant dilatation of the ascending aorta, a combination of aortic replacement and valve reconstruction can achieve stable results even in bicuspid valve anatomy.

Adult↗
PubMed2000

Comparative rest and exercise hemodynamics of 23-mm stentless versus 23-mm stented aortic bioprostheses.

BACKGROUND: The hemodynamic superiority of stentless valves at rest has been generally accepted, but there is a lack of studies on exercise hemodynamics. METHODS: We assessed aortic valve hemodynamics at rest and during exercise in 10 patients with a 23-mm stentless aortic bioprosthesis (Medtronic Freestyle; Medtronic Europe SA/NV, St. Stevens Woluwe, Belgium), in 10 patients with a 23-mm stented aortic bioprosthesis (Carpentier-Edwards, SAV, model 2650; Baxter Edwards AG, Horw, Switzerland), and in 10 healthy volunteers (control group) by means of Doppler echocardiography. RESULTS: Gradients at rest and gradients on comparable maximum exercise levels were significantly lower in patients with stentless valves compared to those with stented valves (rest: 6 +/- 2/11 +/- 4 mm Hg [mean/peak] versus 12 +/- 3/21 +/- 10 mm Hg; exercise: 9 +/- 3/18 +/- 6 mm Hg [mean/peak] versus 22 +/- 8/40 +/- 11 mm Hg). Patients with stentless valves revealed, in comparison to healthy young men, significantly higher gradients, but the small gradient difference of 3/7 mm Hg (mean/peak) at rest remained nearly unchanged throughout the exercise protocol (4/8 mm Hg [mean/peak] at 25 W, 4/9 mm Hg at 50 W and 4/9 mm Hg at 75 W). In contrast, the gradient difference between patients with stented and stentless valves increased significantly from one exercise level to the next (6/12 mm Hg [mean/peak] at rest, 8/14 mm Hg at 25 W, 12/17 mm Hg at 50 W, and 15/25 mm Hg at 75 W). CONCLUSIONS: A stentless aortic bioprosthesis seems to be an appropriate aortic valve substitute, especially in patients who perform regular physical exercise.

Aged↗
PubMed2000

Mitral-valve repair without annuloplasty rings: results after repair of anterior leaflet versus posterior-leaflet defects using polytetrafluoroethylene sutures for chordal replacement.

OBJECTIVE: Defects of the anterior mitral leaflet (AML), including ruptured chordae, are often regarded as difficult or even impossible to repair. Chordal replacement may also be an option in extensive disease of the posterior mitral leaflet (PML). It has not yet been clearly defined whether the repair of either mitral leaflet using chordal-replacement techniques is as safe as the standard repair of the mitral valve (MV) including quadrangular resection and ring reduction alone. METHODS: Between October 1995 and June 1999, 160 patients underwent MV repair for mitral regurgitation (MR) in our institution. Chordal replacement with polytetrafluoroethylene (PTFE) sutures for elongated or ruptured chordae was performed in 72 (45%) patients. These patients were divided into two groups according to the location of the MV lesions: 48 patients with prolapse of the anterior or both leaflets (AML group) received an average of 2.2+/-1. 1 PTFE sutures for repair; in 24 patients with isolated PML defects (PML group), we used an average of 1.5+/-0.8 PTFE sutures. No prosthetic annuloplasty rings were used. Dilatation of the posterior mitral ring was corrected by PTFE suture annuloplasty. The remaining 88 patients underwent a standard mitral repair without chordal replacement. There were no statistically significant (NS) differences between the two groups (AML/PML) regarding age (59/62 years, P=0.49), left ventricular (LV) ejection fraction (64/66%, P=0. 6) and preoperative NYHA class (2.9/2.9, P=0.36). Postoperatively, all patients were followed by serial transthoracic echocardiography at 1 week and after 3, 6, 12 and 24 months by the same investigator. RESULTS: In-hospital mortality was 4.2% (2/48) in the AML group and 0% (0/24) in the PML group (P=0.55). Three of the AML patients (6. 3%) and one PML patient (4.2%) underwent reoperation for recurrent MR (P=1.0). The 1- and 2-year freedom from MV reoperation was 95. 1+/-3.4 and 92.6+/-4.2% in the AML group versus 95.0+/-4.9 and 95. 0+/-4.9% (P=0.67). The 1- and 2-year freedom from residual or recurrent MR grade 2 or higher was 97.6+/-2.4 and 94.9+/-3.5% (AML) versus 95.8+/-4.0 and 95.8+/-4.0% (PML) (P=0.97). CONCLUSIONS: We were unable to find statistically significant differences concerning mortality, freedom from recurrent MR and MV reoperation between the AML and PML groups. Extensive prolapse or chordal pathology of the anterior and PML can be corrected by chordal replacement. Using these techniques, stable repair can be achieved in more than 90% of patients at mid-term follow-up. Long-term observations are necessary to confirm the durability of this type of MV repair.

Adult↗
PubMed2000

Differences in gene density on chicken macrochromosomes and microchromosomes.

The chicken karyotype comprises six pairs of large macrochromosomes and 33 pairs of smaller microchromosomes. Cytogenetic evidence suggests that microchromosomes may be more gene-dense than macrochromosomes. In this paper, we compare the gene densities on macrochromosomes and microchromosomes based on sequence sampling of cloned genomic DNA, and from the distribution of genes mapped by genetic linkage and physical mapping. From these different approaches we estimate that microchromosomes are twice as gene-dense as macrochromosomes and show that sequence sampling is an effective means of gene discovery in the chicken. Using this method we have also detected a conserved linkage between the genes for serotonin 1D receptor (HTR1D) and the platelet-activating factor receptor protein gene (PTAFR) on chicken chromosome 5 and human chromosome 1p34.3. Taken together with its advantages as an experimental animal, and public access to genetic and physical mapping resources, the chicken is a useful model genome for studies on the structure, function and evolution of the vertebrate genome.

Animals↗
PubMed2000

Construction and characterization of a gridded cattle BAC library.

A bovine genomic large-insert bacterial artificial chromosome (BAC) library has been constructed from leukocytes of a Holstein-Friesian male. Size fractionated DpnII-digested genomic DNA was ligated to the dephosphorylated BamH1 ends of a pBACe3.6 vector. Approximately 8.3 x 10(4) individual BAC clones were picked into 384-well plates. Two-hundred and sixty-seven randomly chosen clones were characterized by pulsed-field gel electrophoresis (PFGE). The average insert size was 104 kb with a frequency of clones without inserts of 5.5%. Thirty-four BAC clones were mapped by fluorescence in situ hybridization (FISH) to cattle chromosomes. Three showed signals at more than one location, one of them on the centromeric regions of all autosomes, indicating that the clone contains centromeric repeats. A subset of these BAC clones was used for the development of sequence tagged sites. Both subcloning and direct sequencing of the BACs were used for generating sequence tagged site information. The clones from the library were gridded onto high-density membranes, and PCR superpools were produced from the same set of clones. Membranes and superpools are available through the Resource Centre of the German Human Genome Project in Berlin (http:// www.rzpd.de).

Animals↗
PubMed2000

Characterization and chromosomal localization of the chicken avidin gene family.

Chicken avidin is a biotin-binding protein expressed under inflammation in several chicken tissues and in the oviduct after progesterone induction. The gene encoding avidin belongs to a family that has been shown to include multiple genes homologous to each other. The screening and chromosomal localization studies performed to reveal the structure and organization of the complete avidin gene family is described. The avidin gene family is arranged in a single cluster within a 27-kb genomic region. The cluster is located on the sex chromosome Z on band q21. The organization of the genes was determined and two novel avidin-related genes, AVR6 and AVR7, were cloned and sequenced.

Animals↗
PubMed2000

Comparison of two different meat inspection techniques.

Field studies of meat inspection procedures in three different slaughter houses were performed in Germany, in 1996. In total 22,634 fattening pigs from 63 farms were inspected twice, using a visual and the traditional (mandatory inspection system) procedure. Statistical analysis was performed using the rate of ND+ (Non-Detected Positives) for both visual and traditional inspection. Neither the visual nor the traditional methods detected all lesions which were supposed to be in the lot of animals inspected. Some of the results could be explained by the nature and obviousness of the respective lesion. Conclusions regarding the future performance of inspection should not be drawn before a formal risk analysis procedure for the particular lesion has been done.

Abattoirs↗
PubMed2000

Isolation and characterization of a new FHL1 variant (FHL1C) from porcine skeletal muscle.

Four and a half LIM domain protein 1 (FHL1) was initially described as an abundant skeletal muscle protein with four LIM domains and a GATA like zinc finger. FHL1 was shown to be expressed in skeletal muscle as well as in a variety of other tissues. Recently, alternatively spliced FHL1 mRNAs were identified coding for C-terminal truncated proteins. The tissue distribution of these variants is more restricted and their functional properties seem to be different. We have isolated and characterized a new variant of FHL1 from porcine skeletal muscle (FHL1C). FHL1C is characterized by a newly identified start codon resulting in a 16 amino acids longer N- terminal region. We have isolated and characterized the porcine FHL1C gene spanning approximately 14 kb and harboring six exons. Using primer extension analysis, the transcription start site of FHL1C was mapped, indicating that FHL1C is regulated by an alternative promoter. The tissue distribution of FHL1C expression was studied by RT-PCR. The porcine FHL1C gene was assigned to the distal part of the long arm of the X chromosome by fluorescence in situ hybridization and screening of a somatic porcine/rodent cell hybrid panel.

Alternative Splicing↗
PubMed2000

Comparison of aortic valve gradient during exercise after aortic valve reconstruction.

PURPOSE: Aortic valve preservation is a promising alternative to conventional composite replacement of aortic valve and ascending aorta. This approach may have a physiologic benefit compared with valve replacement similar to that seen in mitral valve reconstruction. We investigated aortic valve gradients at rest and during exercise in patients who had undergone valve-preserving aortic replacement and compared them with composite replacement of valve and aorta. METHODS: Four groups were studied: nine patients underwent composite valve replacement (group A: valve diameter, 23 to 27 mm), eight patients underwent remodeling of the aortic root (group B), and another nine patients had reimplantation of the aortic valve (group C). Healthy volunteers were studied as a control group (group D). Using continuous-wave Doppler echocardiography, all patients were examined on a bicycle ergometer for aortic valve gradients (0 to 75 W). RESULTS: There were no differences among the groups with respect to age, body surface, left ventricular end-diastolic diameter, fractional shortening, or left ventricular mass. Maximum resting gradients were significantly elevated in group A compared with groups B, C, and D (group A: 21.3 +/- 7.1 mm Hg; group B: 9.0 +/- 4.5 mm Hg; group C: 8.6 +/- 3.7 mm Hg; group D: 4.9 +/- 1.6 mm Hg; p < 0.05). At 75 W, group A exhibited significantly higher gradients than all other groups (group A: 31.3 +/- 7.5 mm Hg; group B: 13.9 +/- 6.6 mm Hg; group C: 12.8 +/- 3.5 mm Hg; group D: 9. 2 +/- 1.9 mm Hg; p < 0.05). There was no significant difference among the other groups. Both valve-preserving groups had only insignificantly higher gradients than the control group. CONCLUSION: Our data strongly support the suggestion that preserving the aortic valve restores nearly normal hemodynamic function of the aortic valve. Long-term observations will have to prove the clinical relevance of restoring physiologic aortic valve hemodynamics.

Adult↗
PubMed2000

Structural analysis and transcript processing of the bovine proteolipid protein (PLP) gene.

In this study we present the complete genomic structure of the bovine PLP gene and its assignment to the long arm of the X-chromosome (BTXq2.1). We determined a total of 18,767 bp of the bovine PLP gene and compared it to the human heterolog. A very high similarity was detected between the non-coding regions, interrupted primarily by several transposable elements. A deletion of 13 bp in the vicinity to the translation start signal in the promoter of the bovine PLP gene was found. Functional studies of the 3' region showed the use of several polyadenylation signals. Three main transcripts were detected in adult cattle in the range of 3200, 2400, and 1600 nucleotides using Northern blot analysis. An additional shorter transcript was detected in the cerebrum of calves.

Alternative Splicing↗
PubMed2000

[Procedures in abattoirs and meat inspection. State of the discussion on the implementation of alternative systems].

Results of field studies which were performed in EU member states and which dealt with meat inspection procedures in fattening pigs were reviewed with respect to their contribution to alternative systems of meat inspection. The following was concluded: Inspection ante mortem (monitoring of circumstances at the farm of origin): Data which should be given to the notice of the authorities have not yet been satisfactorily defined and their informative value still is not yet clear The predictive character of information from the farm of origin regarding the health status of the animals (results of meat inspection) is not yet sound enough The technique of ante mortem inspection should be reconsidered also. Meat inspection (monitoring and assessment of lesions): In all studies the compared techniques (visual and official procedure) did not entirely find all lesions, which were supposed to be on the carcasses and organs. This was true in different percentages. The impact on consumer's health from the lesions monitored has to be discussed more thoroughly. The information presently available is not yet sound enough to generate a new practicable system of meat inspection. Further pilot studies are necessary.

Abattoirs↗