PubMed HealthSearch

Biomedical subjects

M J Harvey

Publications and source records attributed to M J Harvey.

At least 19 recordsLinked to original sources

Comparison of endocrine changes and ultrasound as means of identifying ovulation in the bitch.

Twenty bitches were monitored through pro-oestrus and oestrus using both circulating plasma hormone levels and ultrasonic examination of the ovaries. Using luteinising hormone (LH) as being the generally accepted optimum indicator of the day of ovulation, comparisons were made of the accuracy of progesterone and ultrasound to identify ovulation. Progesterone agreed with LH in 12 of 20 bitches and was within one day in seven of the other eight. Ultrasound was less accurate in that only four of the 16 estimates agreed, with a further six being within one day. However, if only the bitches which were examined by ultrasound with the latest equipment were included, while only three of 11 coincided, six of the remaining eight were within one day of the LH estimated ovulation. It is concluded that, at present, of the rapid assessments, the measurement of plasma progesterone is a better estimator of ovulation than ultrasound.

Animals

Rapid isolation of human CD34 hematopoietic stem cells--purging of human tumor cells.

Human CD34+ hematopoietic stem cells were purified using a new technology in which monoclonal antibodies are covalently immobilized on polystyrene surfaces. The CD34+ cell isolation scheme involved three sequential processes: (1) purification of bone marrow mononuclear cells; (2) enrichment of CD34+ cells using covalently immobilized soybean agglutinin; and (3) positive selection of CD34+ cells using polystyrene surfaces coated with the anti-CD34 monoclonal antibody ICH3. CD34+ cells purified by this process have both low-to-medium forward light scatter and low 90 degrees light-scatter properties. Moreover, the purified CD34+ cells are greater than 85% viable, express appropriate characteristic surface antigens, and are 10-50-fold enriched in short- and long-term hematopoietic activity. CD34+ cells collected in this manner from bone marrow samples contaminated with radiolabeled breast carcinoma, neuroblastoma, acute myelogenous leukemia, or small cell lung carcinoma cells were 99.9% depleted of the tumor cells. The CD34+ cell selection devices are sterile and are easily scaled-up to process clinical scale bone marrow samples.

Antibodies, Monoclonal

Ovulation, fertilization and early embryonic development in the bitch (Canis familiaris).

Using circulating plasma hormone estimations, ovulation was monitored in bitches. The results obtained indicate that the timing of ovulation bears little relationship to alterations in sexual behaviour. The bitches were killed and reproductive tracts were removed at various intervals after ovulation and ova or embryos were recovered. The embryo stages were assessed visually and some were investigated histologically. Embryonic development, to early blastocyst stage, took place within the oviducts during the first 12 days after ovulation and there was a marked increase in size between the early and late blastocyst. A culture system using cells from the uterine tube supported the development of one 1-cell embryo to the morula stage.

Animals

The use of a bovine plasma progesterone ELISA kit to measure progesterone in equine, ovine and canine plasmas.

A commerical kit designed to measure the concentration of progesterone in bovine plasma using an enzyme-linked immunosorbent assay (ELISA) has been assessed for measuring progesterone in the plasma of horses, sheep and dogs. Without validation, an immunoassay developed for progesterone in one species should not be used to measure progesterone in the plasma of other species. The kit was assessed by using the criteria of parallelism to a standard curve, the recovery of added progesterone, the correlation with an established radioimmunoassay and the detection of physiological change for each of the species tested. The ELISA kit proved to be acceptable for the analysis of progesterone in the plasma of each species, and in particular for the detection of the low concentrations found during the follicular phase and of the subsequent rise during the luteal phase of the oestrous cycle.

Animals

The effect of tetrachlorohydroquinone on hexachlorobenzene-induced porphyria in Japanese quail.

Female Japanese quail received either hexachlorobenzene (HCB, 100 mg/kg . d) or tetrachlorohydroquinone (TCHQ, 175 mg/kg . d) for 10 d as a primary treatment. Following this, a secondary treatment of HCB (100 mg/kg . d) or TCHQ (175 mg/kg . d), alone or in combination, was administered for 1, 5, 10 or 15 d. The primary HCB treatment caused elevated delta-aminolevulinic acid synthetase (ALA-S) activities and small increases in porphyrin concentrations. Subsequent treatment of these birds with lactose resulted in no further increases in porphyrins or ALA-S. TCHQ treatment caused increases in porphyrins similar to those seen with continued HCB treatment. Apparently, despite the fact that TCHQ alone had no affect on ALA-S or porphyrin levels, this compound is able, in the presence of elevated ALA levels to cause porphyria. A combination of HCB and TCHQ administered to HCB-pretreated animals caused a more severe porphyria than did follow-up treatment with either HCB or TCHQ alone.

5-Aminolevulinate Synthetase

Phenotypic intersex (female pseudohermaphroditism) in a dachshund dog.

A male miniature rough-haired dachshund, presented with episodic haematuria, was found to be a female pseudohermaphrodite. A littermate also had an abnormality of the urogenital tract and their dam had received a progesterone implant during pregnancy. Chromosome analysis of the intersex revealed XX/XY mosaicism in certain tissues.

Animals

Hormonal and histological studies in a 61XXY bull.

A Friesian bull with bilateral testicular hypoplasia was diagnosed as having a pure 61XXY karyotype. The bull displayed normal sexual behaviour but was azoospermic. At 17 months, the animal's peripheral plasma androgen levels appeared to be lower than normal, and one testicle removed one month later showed small seminiferous tubules totally lacking in germ cells. The Leydig cell volume of this testis was well within the normal range but the tubule length was rather short. At 33 months of age an increase in peripheral plasma androgen levels was noted. In the remaining testis there had been both a considerable rise in Leydig cell volume and a fall in tubule length. These findings may be explained by the interaction of three factors; the effects of the abnormal karyotype, the increased maturity of the animal at 33 months and the reaction of the remaining testis to unilateral castration.

Androgens

The selective retardation of NADP+-dependent dehydrogenases by immobilized procion red HE-3B.

The capacities of Procion Red HE-3B and Cibacron Blue F3G-A immobilized to Sepharose CL-4B and Matrex 201R for NAD+-, NADP+- and NAD(P)+-dependent dehydrogenases were measured. Procion Red HE-3B columns retarded NADP+-dependent dehydrogenases more effectively than NAD+-dependent dehydrogenases, whilst immobilized Cibacron Blue F3G-A retarded NAD+-dependent dehydrogenases more effectively than NADP+-dependent dehydrogenases. The capacity of procion Red HE-3B-Sepharose CL-4B for five dehydrogenases was highest in the region of 70nmol of immobilized ligand/ml of settled gel. The effects of using poly(ethyleneimine) as a spacer for both porous and pellicular supports were also examined. Four NADP+-dependent dehydrogenases were purified from yeast extract by using Procion Red HE-3B-Sepharose CL-4B. Two NAD+-dependent dehydrogenases were purified from the same source using Cibacron Blue F3G-A-Sepharose CL-4B. These results are discussed in relation to the use of immobilized Procion Red HE-3B to purify dehydrogenases. This immobilized dye's chromatograhic behaviour is compared with that of immobilized nucleotides. The most important feature of immobilized tirazine dyes seems to be their high operational capacities when compared with group-specific nucleotide adsorbents.

Chromatography, Affinity

Meiosis and spermatogenesis in bulls heterozygous for a presumptive 1/29 Robertsonian translocation.

Bulls heterozygous for the 1/29 Robertsonian translocation showed normal mating behaviour, semen quality and spermatogenesis. The karyotypes of 90 offspring of one heterozygous bull were consistent with a normal 1:1 segregation of the translocation. There was no difference in overall chiasma frequency at diakinesis between heterozygous and normal bulls, and while a trivalent was noted at diakinesis the chiasma position within the No. 1 arm of the trivalent did not appear to be altered when compared with that found in the normal No. 1 bivalent. An increased frequency of aneuploid secondary spermatocytes at the second meiotic division (M II) was found in the heterozygous bulls, the rate of non-disjuction based on the proportion of hypermodal cells being raised from 2.8% in the normal to 6.4% in the heterozygous animals.

Animals

A 14/20 Robertsonian translocation in Swiss Simmental cattle.

A chromosomal abnormality identified as a 14/20 Robertsonian translocation by measurement and banding studies has been found randomly in several Swiss Simmental cattle. These cases have all been traced back to one ancestral bull. The testicular function of three unselected male offspring, two heterozygotes and one normal was studied. All possessed apparently normal spermatogenesis. In a meiotic study no alteration of overall chiasma counts were found at diakinesis in the heterozygous bulls compared with the normal, while the presence of a trivalent confirmed the diagnosis of a Robertsonian translocation. Also in the heterozygotes a small number of secondary spermatocytes were identified but they were too few to draw any firm conclusions regarding alterations in non disjunction rate.

Animals

Arthrogryposis-palatoschisis and a 1/29 translocation in a Charolais herd.

The congenital condition of arthrogryposis palatoschisis was found in two closely related Charolais calves and has subsequently been found in a number of other related animals. It would appear from this and earlier reports that the condition is inherited, possibly as an autosomal recessive. A 1/29 Robertsonian translocation was also found in one of the calves and this was inherited from its dam. It is considered that the two conditions are not directly related.

Animals

An examination of potential matrices for the affinity chromatography of NADP+-linked dehydrogenases with special reference to 6-phosphogluconate dehydrogenase.

1. 6-phosphogluconate dehydrogenase from sheep liver has been purified 350-fold by affinity chromatography with a final specific activity of 18 micronmol of NADP+/reduced min per mg of protein and an overall yield of greater than 40%. 2. A systematic investigation of potential ligands has been carried out: these included 6-phosphogluconate and NADP+, pyridoxal phosphate and several immobilized nucleotides. The results indicate that NADP+ is the most suitable ligand for the purification of 6-phosphogluconate dehydrogenase. 3. The effects of pH and alternative eluents have been examined in relation to the parameters known to affect the desorption phase of affinity chromatography; careful manipulation of the elution conditions permitted the separation of glucose 6-phosphate dehydrogenase, glutathione reductase and 6-phosphogluconate dehydrogenase from sheep liver on NADP+-Sepharose 4B. 4. A large-scale purification scheme for 6-phosphogluconate dehydrogenase is presented that uses the competitive inhibitors inorganic pyrophosphate and citrate as specific eluents.

Animals

Affinity chromatography on immobilised nucleotides. Some applications to the purification of thermophilic dehydrogenases and kinases.

The effect of pH and temperature on the capacity and binding of Bacillus stearothermophilus, alcohol dehydrogenase and phosphofructokinase to N6-(6-aminohexyl)-5'-AMP-Sepharose has been examined. Specific elution from the substituted AMP-Sepharose was examined using a variety of cofactors, fragments of cofactors and substrates. A purification scheme for each enzyme on the substituted AMP-Sepharose using nucleotides and gradients of pH and salt is presented. Interestingly, elevated temperature increased the affinity of both enzymes for N6-(6-aminohexyl)-5'-AMP-Sepharose, however, the Michaelis constant for nucleotide determined at various temperatures remained constant. The effect of pH and salt concentration on the binding of B. stearothermophilus glyceraldehyde-3-phosphate dehydrogenase to 6-aminohexanoyl-NAD+-Sepharose was also examined; raising the pH above 7.5 lowers the capacity of the matrix and the effect of a range of ammonium sulphate concentrations on the adsorption of the enzyme was examined. A specific purification of glyceraldehyde-3-phosphate dehydrogenase from partially purified extracts of this organism was achieved.

Adenosine Monophosphate