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Biomedical subjects

K J Moore

Publications and source records attributed to K J Moore.

At least 109 records · Page 6Linked to original sources
PubMed1989

Disappearance of hemicellulosic monosaccharides and alkali-soluble phenolic compounds of normal and brown midrib sorghum x sudangrasses fed to heifers and sheep.

Eight yearling Holstein heifers (330 kg) were utilized in two 4 x 4 Latin squares. Diets were normal and brown midrib genotypes of Redlan x Greenleaf and Redlan x Piper varieties of ensiled first-cutting sorghum-sudangrass harvested at early head stage of maturity. Composition of hemicellulosic monosaccharides and alkali-soluble lignin phenolic compounds in feeds and corresponding digestibilities were estimated. Arabinose, xylose, and uronic acids were more digestible in brown midrib genotypes than in normal genotypes. p-Coumaric acid disappearance was higher in heifers consuming normal genotypes than in those on brown midrib mutants. In a second experiment, four Suffolk wethers with ruminal, duodenal, and ileal cannulae were utilized in a 4 x 4 Latin square design. Diets were second-cutting sorghum-sudangrass harvested at prehead stage of maturity as baled hay. Digestibilities were determined in the same manner as for heifers. Brown midrib genotypes had higher hemicellulosic monosaccharides, galactose, and uronic acids than did normal genotypes. Xylose content of the brown midrib mutant of Redlan x Piper was higher than that of the corresponding normal genotype. Total tract galactose digestibility was higher in brown midrib genotypes than in normal genotypes. Total tract hemicellulose digestibility (estimated by summing fractional digestibilities of hemicellulosic monosaccharides) was higher in brown midrib mutants than in normal genotypes.

Animal Feed↗
PubMed1989

Disappearance of hemicellulosic monosaccharides and alkali-soluble phenolic compounds of normal and brown midrib sorghum x sundangrass silages fed to Holstein steers.

Four ruminally cannulated Holstein steers fed ad libitum were used in a 4 x 4 Latin square design. Feeds were normal and brown midrib genotypes of Redlan x Piper and Redlan x Greenleaf sorghum-sudangrasses. An in situ trial was run in conjunction with the digestibility trial as part of the data collection for each period. Hemicellulosic monosaccharide and alkali-soluble lignin phenolic compound disappearances were quantitated. The xylose to arabinose ratio was higher in normal genotypes than in brown midribs. Normal genotypes had higher concentrations of alkali-soluble p-coumaric acid and lower vanillin, vanillic acid, and sinapic acid than did brown midrib mutants. Disappearance of p-coumaric acid was higher in steers consuming normal genotypes than in those consuming brown midribs. Neutral detergent fiber, acid detergent fiber, hemicellulose, cellulose, and acid detergent lignin showed no genotypic differences in rate of digestion, but extent of 72 h digestion was higher for brown midrib mutants than for normal genotypes. Extent of digestion of the hemicellulosic monosaccharides, xylose, and uronic acids was higher in situ for brown midrib silages compared with normal genotypes. Differences in alkali-soluble phenolic compound and cell wall monosaccharide profiles between normal and brown midrib genotypes may help explain digestibility differences between the two genotypes.

Animal Feed↗
PubMed1988

Genome organization and polymorphism of the murine beta-glucuronidase region.

Thirty-eight kilobases of mouse genomic DNA which surround and include the coding sequences for beta-glucuronidase has been mapped. Intron-exon arrangements were determined by hybridization of genomic sequences with cDNA clones, and minimum estimates of gene length (11-17 kb) and intron number were obtained. Only a single gene was observed when genomic DNA was probed with subclones containing beta-glucuronidase coding sequence; there was no evidence of duplicated or pseudogenes. However, sequences distal to the 3' end of the gene are present elsewhere in the genome in a limited number of copies. Eight haplotypes of the beta-glucuronidase region with differing regulatory genotypes were compared for restriction fragment polymorphisms. Surprisingly little was found, considering the diverse origin of the haplotypes. Two of the polymorphisms that were found may be correlated with regulatory phenotypes. A BamHI site is missing from the CS and CL haplotypes that share regulatory properties, and a 0.2-kb insertion is consistently present in haplotypes showing increased response to induction by androgens in kidney.

Animals↗
PubMed1988

Dilute suppressor dsu acts semidominantly to suppress the coat color phenotype of a deletion mutation, dl20J, of the murine dilute locus.

The murine dilute suppressor (dsu) gene is the only unlinked trans-acting suppressor identified in mammals. dsu, which was originally reported to be recessive, was recognized by its ability to suppress the coat color phenotype of a retroviral insertion mutation, dv, of the murine dilute (d) locus. This insertion mutation resulted from the integration of an ecotropic murine leukemia virus into noncoding sequences of the dilute gene. Therefore, dsu may act like other allele-specific recessive suppressors identified in Drosophila melanogaster and yeast that suppress mutations induced by retrotransposon insertions. To investigate this possibility, we have examined whether dsu could suppress a spontaneously arising allele of d, dl20J, which is shown here to result from a 3.5-kilobase deletion. These studies indicate that dsu does not function like other eukaryotic suppressor genes that suppress retrotransposon-induced mutations. We also show that dsu is not, as originally reported, a recessive gene but is semidominantly inherited. Collectively, these results allow us to propose a mechanism for the suppressor activity of dsu.

Alleles↗
PubMed1988

The murine dilute suppressor gene dsu suppresses the coat-color phenotype of three pigment mutations that alter melanocyte morphology, d, ash and ln.

The murine dilute suppressor gene, dsu, was identified because of its ability to suppress the dilute coat color of mice homozygous for the retrovirally induced allele (dv) of the dilute locus (d). dsu is unlinked to the d locus and has recently been shown to be semidominantly inherited. The dilute phenotype of d/d mice is the consequence of abnormal melanocyte morphology. While wild-type melanocytes are dendritic, d/d melanocytes are adendritic. dsu apparently suppresses the dilute phenotype by restoring normal melanocyte morphology. In addition to d, two other loci, ashen (ash) and leaden (ln), have been identified that produce a diluted coat color associated with adendritic melanocytes. Interestingly, d and ash are closely linked on chromosome 9 while dsu and ln are located on chromosome 1. In experiments described here, we present genetic mapping data between ash and d indicating that, despite their identical phenotypes, they are separate genes and are not intragenic complementing alleles of the same locus. We also show that dsu is only loosely linked to ln (approximately 9 cM proximal) and that dsu can suppress, at least partially, the coat color of ln/ln mice and ash/ash mice. The partial suppression of ln and ash coat colors is associated with the partial restoration of normal melanocyte morphology. These studies provide new insights into the mechanism of action of dsu and into the interrelationships between members of a family of pigment genes.

Animals↗
PubMed1988

Effects of alkaline hydrogen peroxide treatment of cotton and wheat straw on cellulose crystallinity and on composition and site and extent of disappearance of wheat straw cell wall phenolics and monosaccharides by sheep.

Effects of alkaline hydrogen peroxide (AHP) treatment on cellulose crystallinity and cell wall phenolic monomer and monosaccharide composition were measured using cotton and wheat straw (WS). Two WS treatments were used in this study, Type I WS, for which pH is not regulated during AHP treatment, and Type II WS, for which pH is regulated at 11.5 +/- .2 during AHP treatment. Wheat straw had a lower degree of cellulose crystallinity than cotton, but no differences occurred between treated and untreated substrates. Alkali-labile and nitrobenzene-extractable phenolic monomer concentrations were generally lower for Type I and Type II WS compared with untreated WS. Concentrations of glucose were higher and xylose and arabinose lower in Types I and II WS than in untreated WS. Disappearance of alkali-labile phenolic monomers and cell wall monosaccharides by wethers fed diets containing Type I (Exp. 1) or Type II (Exp. 2) AHP-treated WS were determined. Apparent digestibility of glucose and xylose before the duodenum, and of glucose, xylose and arabinose in the total tract, was greatest (P less than .05) when sheep were fed AHP-treated WS diets in both experiments. In Exp. 2, disappearance of alkali-labile phenolic monomers was greatest (P less than .05) before the duodenum and in the total tract when sheep were fed AHP-treated WS diets. Treatment of WS with AHP modified cell wall composition and increased cell wall monosaccharide digestion by sheep.

Animal Feed↗
PubMed1988

Effect of brown midrib and normal genotypes of sorghum X sudangrass on ruminal fluid and particulate rate of passage from the rumen and extent of digestion at various sites along the gastrointestinal tract in sheep.

The objectives of this experiment were to determine fluid and particulate rate of passage from the rumen and extent of digestion at various sites along the gastrointestinal tract in sheep fed normal and brown midrib sorghum X sudangrass hybrids. Four Suffolk wethers (80 kg) with ruminal, duodenal and ileal cannulae were assigned to one of four diets in a 4 X 4 Latin square with a 2 X 2 factorial arrangement of treatments. Diets were hays of two sorghum X sudangrass varieties, Redlan X Greenleaf and Redlan X Piper, and their corresponding brown midrib mutants. There were no compositional differences resulting from variety or genotype in lignin content or fiber components, although alkali-soluble phenolic acids were higher in normal genotypes than in brown midrib. Vanillin was lower, whereas para-coumaric acid was higher, in normal genotypes than in brown midrib mutants. Ruminal digestibility of neutral detergent fiber, acid detergent fiber and cellulose was lower (P less than .05) for normal genotypes than for the brown midribs. Total-tract digestibility of cellulose was higher (P less than .05) for brown midrib mutants than for corresponding normal genotypes. No quantitative differences in fiber composition or lignin content were detected between normal and brown midrib genotypes; however, differences in composition of alkali-soluble phenolic acids of the lignin fraction could explain differences in digestibility detected between the two genotypes.

Animal Feed↗
PubMed1988

In situ digestion kinetics and ruminal turnover rates of normal and brown midrib mutant sorghum x sudangrass hays fed to nonlactating Holstein cows.

Four nonlactating Holstein cows were fed all-forage diets, consisting of two brown midrib mutant sorghum x sudangrass hybrids (Redlan x Greenleaf and Redlan x Piper) and their normal counterparts, to assess the effects of the brown midrib mutation on the rate and extent of in situ cell wall digestion and on ruminal liquid and particulate turnover rates. The four diets were preserved as hay and coarsely chopped prior to feeding in a 4 x 4 Latin square design. Brown midrib genotypes had lower NDF, acid detergent lignin, and hemicellulose concentrations than did normal genotypes. There was no significant difference between brown midrib and normal diets in the rate of in situ cell wall digestion or in digestion lag time. However, brown midrib diets had greater extent of digestion and greater apparent digestibility than normal diets. There was no difference between genotypes in ruminal liquid or particulate turnover rates. In this experiment, lignin concentration had no effect on the rate of in situ digestion or on the rate of ruminal digesta flow.

Animal Feed↗
PubMed1988

The dilute coat-color locus of mouse chromosome 9.

The genetic and molecular analysis clearly defines the dilute gene as essential for normal melanocyte morphology, neurological function and juvenile survival. The large number of dilute mutations afford a strong basis for clarifying the precise genomic organization and expression pattern at dilute. Ultimately, such an analysis will provide the tools for the subsequent molecular examination of the numerous loci which define the dilute complex of mouse chromosome 9 as critical for normal mammalian development.

Alleles↗
PubMed1987

Analysis of bovine udder, plate and viscera using near infrared reflectance spectroscopy.

The objective of this study was to evaluate near infrared reflectance spectroscopy (NIRS) as an accurate and inexpensive alternative to conventional chemical analyses of nonconsumer bovine tissue. Udder, plate and visceral samples were collected from mature, Charolais-Angus and Hereford-Angus crossbred beef cows at slaughter, ground and analyzed for concentrations of lipid, protein and dry matter using standard AOAC chemical procedures. Samples were analyzed using NIRS. The collection of samples was randomly split into separate calibration and validation sets. Nine calibration equations representing each constituent and tissue combination were developed, using first- or second-order derivative mathematical transformations, and those calibration equations were validated. Correlation coefficients of calibration (R) and validation (r) ranged from .95 to .98 and from .87 to .97, respectively, for all analyses except plate dry matter (r = .77). Standard errors of calibration and prediction ranged from 1.89 to 5.81%. Results from this study are interpreted to indicate that bovine udder, plate and visceral tissue composition can be accurately, quickly and efficiently predicted using NIRS technology.

Animals↗
PubMed1987

Rumen turnover and digestion of normal and brown midrib sorghum x sudangrass hybrid silages in dairy cattle.

Eight growing Holstein heifers and four ruminally cannulated adult Holstein steers fed ad libitum were used in 4 X 4 Latin square designs. Diets included two sorghum X sudangrass varieties, Redlan X Greenleaf and Redlan X Piper, and their corresponding brown midrib mutants. Acid detergent fiber and acid detergent lignin concentrations tended to be lower for brown midrib mutants than for normal genotypes of the same variety. Digestion kinetics for in situ studies showed no difference in rate constants between normal and brown midrib sorghums, but extent of digestion at 72 h was significantly higher for brown midrib mutants than for normal genotypes, suggesting that lignin has no effect on digestion rate but does result in a decreased extent of digestion. In growing dairy heifers, brown midrib sorghum X sudangrass had higher digestibilities for organic matter, neutral detergent fiber, acid detergent fiber, cellulose, and hemicellulose fractions than did the normal genotype for Redlan X Greenleaf.

Animal Feed↗
PubMed1984

X chromosome-linked muscular dystrophy (mdx) in the mouse.

An X chromosome-linked mouse mutant (gene symbol, mdx) has been found that has elevated plasma levels of muscle creatine kinase and pyruvate kinase and exhibits histological lesions characteristic of muscular dystrophy. The mutants show mild clinical symptoms and are viable and fertile. Linkage analysis with four X chromosome loci indicates that mdx maps in the Hq Bpa region of the mouse X chromosome. This gives a gene order of mdx-Tfm-Pgk-1-Ags, the same as for the equivalent genes on the human X chromosome.

Animals↗
PubMed1981

An allele (Pk-1b) from wild-caught mice that affects the activity and kinetics of erythrocyte and liver pyruvate kinase.

A true breeding strain was made from a wild-caught mouse with low erythrocyte pyruvate kinase (E.C. 2.7.1.40) activity. This variation showed additive inheritance and segregated as an allele at a single locus (Pk-1b). Mice homozygous for the reduced blood pyruvate kinase activity cosegregated for reduced liver activity. In both these tissues the variant enzyme had a lowered heat stability and reduced Km values for ADP. An increased stimulation by FDP was also detected in the liver pyruvate kinase. No difference in the isoelectric point of the variant enzyme in either erythrocyte or liver was observed when compared with the enzyme from C57BL mice (Pk-1a/Pk-1a). It is concluded that Pk-1 is the structural gene for the erythrocyte and the major liver pyruvate kinase. No other tissue pyruvate kinase showed altered characteristics.

Alleles↗
PubMedDate not supplied

Family history of seizures in posttraumatic and alcohol-associated seizure disorders.

The potential role of genetic factors in the etiology of posttraumatic and alcohol-associated seizures was studied in 289 male patients with recurrent seizures and in 174 individuals who had never experienced a seizure. The incidence of seizures in first-degree relatives of probands was compared with that in relatives of unaffected individuals. Relatives of patients with alcohol-associated seizures had a rate ratio of 2.45 [95% confidence interval (CI) 1.41-4.25], whereas no excess incidence was noted among relatives of posttraumatic epilepsy patients (rate ratio 1.20, 0.64-2.25 CI). Relatives of probands with both antecedents showed an intermediate rate ratio of 1.72 (0.92-3.20 CI). Among probands with alcohol-associated seizures, the rate ratio of 2.05 for patients with alcohol-related seizures (i.e., spontaneously occurring seizures in association with chronic alcohol abuse) was slightly higher than that of 1.85 for probands with alcohol withdrawal seizures. Trauma severity had a slight impact on the incidence of affected relatives; patients with severe head injuries had a rate ratio of 0.73 and probands with milder trauma had a rate ratio of 0.99. The results indicate a limited, if any, role of genetic predisposition in development of posttraumatic seizures. Alcohol-related seizures, however, showed familial aggregation of unprovoked seizures, suggesting an involvement of genetic factors in the origin of such seizures.

Adult↗