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R T Stone

Publications and source records attributed to R T Stone.

At least 73 records · Page 4Linked to original sources
PubMed1994

A conceptual database model for genomic research.

We describe a conceptual model for genome databases that facilitates the process of building, maintaining, and disseminating physically anchored genetic linkage maps. The model has been implemented as a relational database at the Roman L. Hruska U.S. Meat Animal Research Center (MARC). Development of consensus maps using disparate data from different reference pedigrees or laboratories is supported. The model is of use to quantitative and population geneticists interested in loci that affect phenotypes and marker-assisted selection, and it is sufficiently flexible for centralized, species genome databases facilitating comparative mapping. The MARC genome database is used to assemble, maintain, and disseminate physically anchored genetic linkage maps for cattle, swine, and sheep currently based on more than 100,000 genotypes from 1,000 markers. Integrated with linkage analysis software, this database permits frequent updates of physically anchored genetic linkage maps.

Algorithms↗
PubMed1994

A genetic linkage map for cattle.

We report the most extensive physically anchored linkage map for cattle produced to date. Three-hundred thirteen genetic markers ordered in 30 linkage groups, anchored to 24 autosomal chromosomes (n = 29), the X and Y chromosomes, four unanchored syntenic groups and two unassigned linkage groups spanning 2464 cM of the bovine genome are summarized. The map also assigns 19 type I loci to specific chromosomes and/or syntenic groups and four cosmid clones containing informative microsatellites to chromosomes 13, 25 and 29 anchoring syntenic groups U11, U7 and U8, respectively. This map provides the skeletal framework prerequisite to development of a comprehensive genetic map for cattle and analysis of economic trait loci (ETL).

Animals↗
PubMed1994

Linkage of bovine erythrocyte antigen loci B, C, L, S, Z, R' and T' and the serum protein loci post-transferrin 2 (PTF 2), vitamin D binding protein (GC) and albumin (ALB) to DNA microsatellite markers.

Seven bovine erythrocyte antigen loci and three serum protein loci were tentatively assigned to chromosomes or synteny groups by linkage analysis to previously assigned microsatellite DNA markers. The erythrocyte antigen locus EAB was mapped to synteny group U27; EAC to chromosome 18, synteny group U9; EAL to chromosome 3, synteny group U6; EAS to chromosome 21, synteny group U4; EAZ to chromosome 10, synteny group U5; EAR' to chromosome 16, synteny group U1; and EAT' to chromosome 19, synteny group U21. The vitamin D binding protein (GC) and albumin (ALB) loci were assigned to chromosome 6, synteny group U15 and post-transferrin 2 (PTF 2) to chromosome 19, synteny group U21.

Animals↗
PubMed1993

BoLA-DIB: species distribution, linkage with DOB, and northern analysis.

The bovine major histocompatibility complex differs from that of other species in that it has a second group of class II genes that are separated from the classical class I/class II complex by 15 to 20 centimorgans. Two class II bovine genes, BoLA-DYA and BoLA-DIB, seem to be unique based on sequence analysis. To investigate the occurrence of one of these genes, BoLA-DIB, in other species, a DIB 2nd domain exon probe was hybridized to Southern genomic blots containing DNA from representatives from a variety of mammalian families. The probe hybridized only with DNA from representatives of the Cervidae, Giraffidae and Bovidae families, indicating that significant sequence similarity to DIB may be confined to these families. Analysis of the linkage relationship between DIB and DOB in cattle half-sib families did not yield any recombinants among 39 informative offspring, indicating that DIB maps within the second group of class II bovine genes; DOB has previously been mapped to the second group of class II genes. A 1st domain exon probe from BoLA-DQB hybridized to RNA from either stimulated or unstimulated peripheral bovine lymphocytes, while 1st domain exon probes from BoLA-DIB and HLA-DOB gave no hybridization signals, indicating that transcription in peripheral lymphocytes of these genes is at least very minor compared to BoLA-DQB.

Animals↗
PubMed1991

Restriction fragment length polymorphisms in bovine major histocompatibility complex class II beta-chain genes using bovine exon-containing hybridization probes.

Restriction fragment length polymorphisms (RFLPs) have been identified in the bovine MHC class II region using five hybridization probes constructed from two bovine genomic clones. Four probes were constructed from a bovine DR beta-like gene, BoLA-DRB2. These included a probe containing the complete beta 1 exon (R2-beta 1), a probe containing the last 129 base pairs of the beta 2 exon (R2-beta 2), a probe containing intron immediately 5' of the beta 2 exon (R2-5' beta 2), and a probe containing the complete transmembrane exon (R2-TM). A fifth probe was constructed from a novel bovine beta-chain gene, BoLA-DIB, and contained the entire TM exon (I1-TM). R2-beta 1 defined very little polymorphism. R2-beta 2 hybridized to several fragments but one or two fragments hybridized much stronger on all Southern blots and it was presumed these corresponded to BoLA-DRB2 fragments. By using R2-5' beta 2 as a probe, these BoLA-DRB2 fragments were confirmed: 6.4 and 2.7-kb Eco RI alleles, 1.7- and 1.5-kb Pvu II alleles, 5.9-, 5.4-, 3.7- and 1.9-kb TaqI alleles, and a non-polymorphic 22.5-kb BamHI fragment. I1-TM identified three alleles with TaqI. To investigate the linkage between the RFLP alleles, 166 offspring of five sires were tested. Complete linkage was found for all RFLPs identified with the BoLA-DRB2 probes. However, the RFLP patterns of 13 calves out of 58 indicated recombination between BoLA-DRB2 and BoLA-DIB.

Animals↗
PubMed1991

Nucleotide sequence and northern analysis of a bovine major histocompatibility class II DR beta-like cDNA.

A 1.2-kb bovine DR beta-like cDNA clone (BoLA-DRB3) was isolated from a peripheral blood lymphocyte cDNA library utilizing a human DR beta cDNA as a probe. BoLA-DRB3 was found to have a high degree of nucleotide sequence similarity (96.8%) with a previously sequenced bovine DR beta-like gene (A1). It is believed that BoLA-DRB3 and A1 represent distinct alleles of one of the three bovine DR beta-like loci. Sequence comparison of BoLA-DRB3 with genes representing the other two bovine DR beta-like loci resulted in moderate degrees of sequence similarities (83.1% and 86.3%, respectively). Comparison of the relative abundance of RNA transcripts of the three bovine DR beta-like loci by Northern analysis of lymphocyte RNA indicated that BoLA-DRB3 is the most actively transcribed of the three bovine DR beta-like genes. Based on these results we suggest that of the three DR beta-like loci thus far identified in the bovine, only one is actively transcribed.

Amino Acid Sequence↗
PubMed1991

Relationships of serum estriol, cortisol and albumin concentrations with pig weight at 110 days of gestation and at birth.

In polytocous species, animals with reduced birth weights are associated with reduced neonatal survival, which may be related to substandard placental function. At 110 days of gestation (n = 84) and at birth (approximately 114 days, n = 193), fetal pigs were bled and weighed, so that indexes of placental function (estriol), fetal stress (cortisol), and fetal growth (albumin) could be related to fetal development. Concentration of estriol at birth or 110 days of gestation was not linearly related to weight of pig. Pig serum albumin was linearly related to pig weight and increased as body weight increased (p less than 0.05). In blood from pigs sampled at birth, cortisol concentrations significantly decreased as body weight increased (p less than 0.05).

Animals↗
PubMed1991

Effect of the beta-adrenergic agonist L644,969 on muscle growth, endogenous proteinase activities, and postmortem proteolysis in wether lambs.

To examine the effect of a beta-adrenergic agonist (BAA) on muscle growth, proteinase activities, and postmortem proteolysis, 16 wether lambs were randomly assigned to receive 0 or 4 ppm of L644,969 in a completely mixed high-concentrate diet for 6 wk. Weight of the biceps femoris was 18.6% heavier in treated lambs. At 0 h after slaughter, treated lambs had higher cathepsin B (35.6%), cathepsins B + L (19.1%), calpastatin (62.8%), and m-calpain (24.6%) than control lambs, but both groups had similar mu-calpain activities. In both longissimus and biceps femoris muscles, treated lambs had higher protein and RNA and lower DNA concentrations. However, total DNA was not affected, indicating that the increase in muscle mass was probably due to muscle hypertrophy rather than to hyperplasia. The pattern of postmortem proteolysis was significantly altered by BAA feeding. In treated lambs, postmortem storage had no effect on the myofibril fragmentation index and degradation of desmin and troponin-T. These results indicate that the ability of the muscle to undergo postmortem proteolysis has been dramatically reduced with BAA feeding. Similar proteolytic systems are thought to be involved in antemortem and postmortem degradation of myofibrillar proteins, so BAA-mediated protein accretion is probably due, at least in part, to reduced protein degradation. To examine whether protein synthesis was altered with BAA feeding, the level of skeletal muscle alpha-actin mRNA was quantified. Longissimus muscle alpha-actin mRNA abundance was 30% greater in BAA-fed lambs. Collectively, these results indicate that dietary administration of BAA increases muscle mass through hypertrophy and that the increase in muscle protein accretion is due to reduced degradation and possibly to increased synthesis of muscle proteins.

Actins↗
PubMed1990

Investigation of bovine viral diarrhea virus infections in a range beef cattle herd.

Bovine viral diarrhea virus (BVDV) infections resulting in clinical disease developed in calves, despite vaccination of dams and high maternal BVDV antibody titers in calves. Eight persistently infected (PI) calves born to immunocompetent dams were identified in the herd. Neutralizing BVDV antibody titers of PI calves had decreased greatly by the time the calves were 1 to 2 months old. Antibody titers of PI calves decreased more rapidly than antibody titers of calves that were not PI. Reduced antibody titers in PI calves allowed detection of BVDV in serum specimens of all PI calves by the time they were 8 weeks old. Persistent infection in suspect calves was detectable serologically and was confirmed by virologic examination of serum specimens 4 months after weaning, when the calves were 9 months old. Growth rates were reduced in viremic calves.

Animals↗
PubMed1990

Follicle-stimulating hormone regulation of cytochrome P-450 side-chain cleavage messenger ribonucleic acid accumulation by porcine granulosa cells isolated from small and medium follicles.

The experiments described here were conducted to examine regulation of cytochrome P-450 side-chain cleavage (SCC) mRNA accumulation in porcine granulosa cells isolated from small (1-4-mm) and medium (5-6-mm) follicles. Granulosa cells were cultured under the following conditions: 1) for 48 h or 96 h with 0, 50, or 200 ng/ml porcine FSH; 2) for 96 h with 200 ng/ml FSH and aminoglutethimide (100 microM); and 3) for 96 h with forskolin (100 microM). Total RNA was extracted and examined by Northern and dot-blot hybridization analysis, and culture media were assayed for progesterone concentration. Northern blot analysis revealed a single band approximately 2.1 kb in size. Accumulation of SCC mRNA by granulosa cells was both FSH dose- and culture time-dependent (p less than 0.05) with maximal increases approximately 4.5 times control levels. Aminoglutethimide reduced progesterone production by about 80% while having no effect on granulosa cell accumulation of SCC mRNA compared to cells stimulated with 200 ng/ml of FSH. Forskolin-treated cells produced significantly more progesterone than did cells treated with FSH, but accumulation of SCC mRNA was similar. In response to FSH, concentration of SCC mRNA did not vary with follicle size, but granulosa cells from small follicles produced significantly more progesterone than did those from medium follicles. These results demonstrate that concentration of SCC mRNA in cultured porcine granulosa cells is FSH dose-dependent, does not vary significantly in cells from small- and medium-sized follicles, and is correlated with progesterone production, but may not parallel progesterone secretion. This last observation indicates that control at sites other than SCC mRNA can affect progesterone production.

Aminoglutethimide↗
PubMed1990

Partial nucleotide sequence of a novel bovine major histocompatibility complex class II beta-chain gene, BoLA-DIB.

A bovine genomic clone that hybridized to HLA-DQ beta cDNA was isolated and fragments containing the beta 1, beta 2 and transmembrane (TM) exons subcloned. The nucleotide sequences of the exons and flanking intron regions were determined. Comparisons of these exon nucleotide sequences and derived amino acid sequences to human class II beta-chain sequences showed that this gene is only 77% identical to HLA-DQ beta and about 75% identical to bovine DQ beta-like genes. The exon sequences were more divergent from other class II beta-chain genes. However, structural features such as conserved cysteines and regions of amino acids strongly suggest this to be a class II beta-chain gene. When exon-containing fragments were used as hybridization probes on Southern blots of bovine genomic DNA digested with Eco RI or Pvu II, each exon hybridized to a single band. Based on these results we have referred to this gene as a novel bovine class II beta-chain gene, BoLA-DIB.

Amino Acid Sequence↗
PubMed1989

Escherichia coli O114:nonmotile as a pathogen in an outbreak of severe diarrhea associated with a day care center.

Five infants from a day care center developed severe diarrhea associated with enteropathogenic Escherichia coli O114:nonmotile (EPEC O114:NM) and required hospitalization. Five additional cases of diarrhea associated with EPEC O114:NM subsequently occurred, four in hospital contacts of the patients and one in a household contact. Biochemically, all EPEC O114:NM isolates were sorbitol nonfermenters. All isolates produced low concentrations of cytotoxin with a mean of 10(1.23) CD50/mg of protein. Cytotoxin was not neutralized with antibody to Shiga-like toxin I or II. Heat-labile and heat-stable enterotoxins were not present by gene probe analysis. Stool isolates from 9 of 10 hospitalized infants were positive for EPEC adherence factor by colony blot DNA probe analysis. The severity of the disease, sorbitol nonfermentation, and presence of enteroadherence are unusual features of this organism.

Child Day Care Centers↗
PubMed1989

Partial nucleotide sequence of a bovine major histocompatibility class II DR beta-like gene.

A genomic clone containing a bovine DR beta-like gene, BoDR beta II, was isolated from a bovine genomic library and characterized by restriction enzyme mapping and nucleotide sequencing of exon regions. Alignment of this sequence with the human DR beta cDNA sequence allowed identification of exon/intron boundaries. The clone contains a 13.3-kilobase (kb) insert, and includes 1.3 kb 5' of the beta 1 exon and 6.7 kb 3' of the transmembrane (TM) exon. Open reading frames were present in the BoDR beta exons sequenced. Nucleotide identities of the bovine beta 1, beta 2 and TM exons with the corresponding human DR beta exons were 73, 91 and 83%, respectively. Nucleotide identities of these exons with those of a previously described bovine DR beta-like pseudogene, BoDR beta I, were 69, 95 and 81%, respectively. Although a limited amount of sequence data was obtained for the intron regions, a 71% identity was found within a 514-nucleotide region immediately 3' to the beta 2 exons in BoDR beta I and BoDR beta II. A series of GT residues followed by a longer series of GA residues began about 35 nucleotides 3' of the beta 1 exon in both BoDR beta I and BoDR beta II.

Amino Acid Sequence↗