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Biomedical subjects

R R Tremblay

Publications and source records attributed to R R Tremblay.

At least 37 records · Page 2Linked to original sources
PubMed1994

Production practices, calf health and mortality on six white veal farms in Ontario.

A group of 4863 white veal calves reared on six commercial white veal farms in Ontario were followed through production to describe calf characteristics and production levels. Patterns of morbidity, mortality, and culling were investigated at the farm, room and individual level. The majority of the calves were male Holsteins, with approximately half originating from Ontario. The mean average daily gain for shipped calves over the entire production period was 1.1 kg/day (SE = 0.002). The overall percentage of calves receiving at least one individual treatment was 59%, with an average number of treatment days per calf of 3.3. The majority of calves receiving one or more treatment days were first treated between the fourth and seventh week of production. The mortality rate was 3.7%, and 5.1% of the calves were culled. Pneumonia was the largest single cause of death. Peak death and cull losses occurred during the seventh and eighth week of production.

Animal Husbandry↗
PubMed1994

Production indices, calf health and mortality on seven red veal farms in Ontario.

Production, morbidity, mortality and culling were investigated on seven commercial red veal farms in Ontario. The total number of calves included in the study group was 2251. The mean exit weight of marketed calves was 291 kg, with an average daily gain of 1.52 kg/day over the entire production period. The percentage of calves receiving one or more treatment days was 55%, with an average number of individual treatment days per treated calf of 3.9. An increasing number of treatment days, particularly up to eight days of treatment, was associated with decreasing average daily gain, and an increased probability of being lost from production due to death or culling. The percentage of calves which died during production was 5.4, with 0.8% of calves culled.

Animals↗
PubMed1993

Characterization of rhesus monkey prostate specific antigen cDNA.

Using a RT-PCR approach, we obtained two overlapping cDNA clones containing the entire 1.5 kb sequence of rhesus monkey prostate specific antigen (rmPSA). The sequence obtained revealed an open reading frame of 261 amino acids. One potential N-glycosylation site was identified at Asn-78. The calculated molecular mass for the unglycosylated mature protein was 26,147 Da. Extensive amino acid homology (89%) was observed between rmPSA and its human counterpart. These results demonstrate that rhesus monkey and man prostate share a major biochemical component, and suggest that this animal species might be useful to answer specific questions related to human prostatic function and pathology.

Amino Acid Sequence↗
PubMed1993

The major dog pancreas protein recognized by an antiserum to dog prostate kallikrein is the anionic trypsin.

1. On the basis of its immunoreactivity with a polyclonal antiserum to dog prostate kallikrein in Western blot experiments, a 30 kDa protein was purified from the pancreas of the dog using ion-exchange and gel filtration chromatography. 2. That protein was identified as the anionic trypsin by its NH2-terminal amino acid sequence. 3. The immunoreaction occurred despite an overall amino acid homology which was limited to 39% between the prostate kallikrein and anionic trypsin. 4. Otherwise, the anti-prostatic kallikrein antiserum was rather specific since it did not react with dog cationic trypsin, dog renal kallikrein and human prostate specific antigen.

Amino Acid Sequence↗
PubMed1993

Transcriptional regulation of dog prostate arginine esterase gene by androgens.

These studies were designed to define the molecular events involved in the modulation of dog prostate arginine esterase gene expression following short castration intervals and androgen treatment. Arginine esterase enzymatic activity and protein levels decreased about 50% 24 h after castration. Thereafter, a more progressive decrease was observed, resulting in 2-4-fold lower levels in 12-day castrates than in the intact controls. Total prostatic arginine esterase mRNA levels slowly decreased during the first five days after castration but more abruptly thereafter and were about 150-fold lower in 12-day castrated animals. By contrast, in isolated prostatic nuclei, levels of arginine esterase RNA precursors and mature transcripts rapidly fell following orchiectomy, with a 50-70% decrease 24 h after castration. Nuclear run-on experiments confirmed that the latter effects were the result of decreased arginine esterase gene transcription. All these changes could be at least partially reversed by administration of testosterone cypionate. Furthermore, no striking modifications in the proportion of epithelial/stromal cells in the prostatic tissue were observed following orchiectomy. These results show that castration and androgens exert very rapid effects on the gene expression of arginine esterase, and that the regulation occurs at the transcriptional level.

Androgens↗
PubMed1993

Effect of combination treatment with zanoterone (WIN 49596), a steroidal androgen receptor antagonist, and finasteride (MK-906), a steroidal 5 alpha-reductase inhibitor, on the prostate and testes of beagle dogs.

The effects of the steroidal androgen receptor antagonist zanoterone (WIN 49596) and the steroidal 5 alpha-reductase inhibitor finasteride (MK-906) either alone or in combination on prostatic size, histomorphology, and biochemistry were determined in the intact male dog. Additionally, the effects of treatment with zanoterone and/or finasteride on testicular size, serum testosterone and LH levels, and spermatogenesis were determined in the same dogs. Daily oral treatment for 16 weeks with either zanoterone alone at 10 mg/kg.day or finasteride alone at 1.0 mg/kg.day reduced (P < 0.05) the size of the prostate, resulted in mild to moderate diffuse glandular atrophy of the prostate, and decreased prostatic DNA and prostatic arginine esterase (the primary canine prostatic protein) levels compared to those in intact controls. These changes occurred with no effect on testicular weight, testicular histomorphology, daily sperm production, or serum LH levels. Serum testosterone concentrations were increased (P < 0.05) approximately 3-fold in the 10 mg/kg.day zanoterone treatment group compared to those in intact controls. Combination treatment of male dogs for 16 weeks with zanoterone (10 mg/kg.day) plus finasteride (1.0 mg/kg.day) orally also reduced (P < 0.05) prostate size, resulted in moderate to marked diffuse prostatic glandular atrophy, and decreased prostatic DNA and arginine esterase levels more than either drug alone, without affecting testicular size, testicular histomorphology, serum LH concentrations, or serum testosterone concentrations compared to those in intact controls. The effects of combination treatment with zanoterone and finasteride on prostatic size; histomorphology; and DNA, arginine esterase protein, and arginine esterase mRNA levels were similar to those observed in castrate controls. In addition, in situ estimates of prostatic size using transrectal ultrasonography indicated that the median time to 70% prostatic regression in dogs administered combination zanoterone plus finasteride was similar to that in castrate controls (9.6 and 9.3 weeks, respectively), indicating that the combination was more effective in causing prostatic regression than either drug alone. Finally, at the dosages used, no adverse effects of combination treatment with zanoterone plus finasteride on testicular or other major body organ weights were observed. Based on these results, combination therapy using zanoterone and finasteride for the treatment of human androgen-dependent disorders such as benign prostatic hyperplasia and prostate cancer has potential utility.

Androstenes↗
PubMed1992

Demonstration of DNA binding factors interacting with a fragment of the canine prostate arginine esterase gene promoter.

We have studied, by the gel mobility shift assay, the interaction of DNA binding proteins with a fragment of the proximal promoter (from nucleotides -177 to -47) of the androgen-regulated canine prostate arginine esterase gene. Several shifted bands were obtained using nuclear extracts from various tissues. In the case of the prostate, the intensity of some of the shifted bands was decreased or increased when the extracts were prepared from animals that had been castrated 12 days earlier. Several of the DNA-protein complexes could be assigned to an interaction with part or all of the sequence GGGGGTGGGGG from-124 to -114. We also obtained evidence for the presence of protein(s) interacting with an Sp1 motif present in the same fragment. These results suggest that some ubiquitous factors different from the androgen receptors could be involved in the regulation of the arginine esterase gene.

Animals↗
PubMed1992

Rapid, simple and sensitive microassay for skeletal and cardiac muscle myoglobin and hemoglobin: use in various animals indicates functional role of myohemoproteins.

A novel, simple, rapid, sensitive and reproducible microassay is described for determination of myoglobin and hemoglobin content of myocardial and skeletal muscle biopsy specimens from various mammals, birds and fish. As little as 50 mg of tissue is needed and myoglobin concentrations lower than 1 mg% can be detected. Myoglobin and hemoglobin are separated at alkaline pH by ammonium sulfate extraction followed by ultrafiltration. Heme content is determined by absorption of the Soret band when the hemoprotein extract is visibly colored or more sensitively by its peroxidase activity when the extract has low color. The heme reacts with tertiary-butyl hydroperoxide and orthotolidine to generate a blue color. Hemoglobin content is correlated with myoglobin content and is related to aerobic capacity and blood flow to the tissue. Myoglobin content varied over 5 orders of magnitude up to 7 per cent of the weight of tissue, whereas hemoglobin content varied over 2 orders of magnitude up to 6 per cent of tissue weight. Myoglobin content is increased in species with high basal metabolic rate, high physical activity, prolonged diving capacity, fatigue resistance, and red muscle, whereas it is decreased in white muscle, iron-deficient animals, animals with sedentary lifestyles, and in animals and tissues with small fiber diameters such as avian or fish hearts.

Animals↗
PubMed1992

Adrenocorticotrophic hormone fails to alter plasma fibrinogen and fibronectin values in calves but does so in rabbits.

The intramuscular administration of adrenocorticotrophic hormone (ACTH) to calves, in either a short-acting form (cosyntrophin) or a longer-acting form (ACTHAR Gel), failed to induce any alteration in circulating fibrinogen or fibronectin values, despite marked elevations in plasma cortisol concentrations. With the longer-acting ACTH, plasma cortisol was elevated for at least 12 h following treatment and induced the expected physiological response of an elevation in blood glucose. In contrast, both forms of ACTH induced marked increases (p < 0.01) in plasma fibrinogen and fibronectin when administered to rabbits. The elevation in the circulating levels of these proteins was first observed 24 h after ACTH administration, by which time plasma corticosteroid values had returned to pre-treatment values. With both ACTH preparations the increases in the circulating levels of these proteins were sustained for at least 96 h. The results suggest that, in cattle, the well-recognized increases in plasma fibrinogen values following stress are not associated with the concomitant increase in plasma cortisol. Further, the results clearly illustrate the marked species differences in the response of acute-phase reactant proteins to elevated glucocorticoids.

Adrenocorticotropic Hormone↗
PubMed1991

Opposite variations of two epididymal components and blood plasma testosterone in two breeds of rams.

1. Testicular volume (T Vol), blood plasma testosterone (T) concentration, seminal plasma alpha-glucosidase (alpha-G) specific activity, L-carnitine (L-C) concentration as well as semen characteristics were compared in eight Finnish Landrace (F) and eight Suffolk (S) rams throughout 21 months. 2. Only T Vol and T exhibited a typical seasonal variation in both breeds, whereas L-C, alpha-G and live sperm output presented a seasonal profile only in S rams. 3. L-C and alpha-G variations were opposite to those of T in S rams, while they fluctuated in F rams throughout the entire experiment, as did live sperm output. 4. Only the number of ejaculates and T were significantly higher in F rams (3.50 +/- 0.08 in 5 min and 7.62 +/- 0.40 ng/ml) than in S rams (2.30 +/- 0.05 in 5 min and 5.5 +/- 0.30 ng/ml); these two characteristics might therefore be considered as two indexes of sexual activity in rams. 5. By contrast, among all characteristics measured, only alpha-G was significantly higher in S rams than in F rams (1.33 +/- 0.04 vs 0.77 +/- 0.03 mU/mg proteins); this result, as well as seasonal alpha-G profile present in only S rams, allowed us to conclude that alpha-G might be considered as an additional index of seasonal reproduction in rams.

Animals↗
PubMed1991

Variations in 3H-diisopropylfluorophosphate binding proteins in human seminal plasma.

We have characterized the electrophoretic pattern and variations in 3H-diisopropylfluorophosphate (DFP)-binding proteins in human seminal plasma from normal men and from 103 patients attending the infertility clinic of our hospital. This study shows that 34 kDa prostate-specific antigen (PSA) is the major 3H-DFP-binding protein and that two other ubiquitous bands of 100 and 60 kDa are also present in seminal plasma from all the men studied. Additional bands of 92, 50-54 (doublet) and 38 kDa were also observed in some patients. The 38 kDa band was shown to be a highly glycosylated form of PSA. Further complexity was demonstrated by two-dimensional gel electrophoresis in the 27-30 kDa range of the gels since at least 10 major spots and rows of spots were seen. The concentration of these spots, including PSA, was extremely variable, as was their pattern of inhibition by various active site inhibitors of serine-proteases; these variations were not correlated with any specific sperm characteristics. With the exception of PSA, the proteins have not been identified. Their distribution suggests that most of them are exclusively of prostatic origin although a few could also derive from the seminal vesicles or blood. Future studies will be aimed at determining the nature of these proteins and their potential usefulness in andrology.

Antigens, Neoplasm↗
PubMed1991

Elevated in vitro translation of a 25-kDa protein in renal cell carcinoma.

As a first step in understanding the changes in protein synthesis that occur in renal cell carcinoma, we have prepared poly(A)+ RNA from surgically removed tumors and from their normal tissue counterpart. These RNAs were then translated in vitro in the rabbit reticulocyte lysate system and the synthesized labeled polypeptides were separated by one- and two-dimensional gel electrophoresis. A major 25-kDa primary translation product was observed with all renal cell carcinomas. The synthesis of this protein was barely detectable with the RNA from normal tissue adjacent to the tumor. To determine if this protein could be further processed (removal of signal peptide and (or) core glycosylation), canine pancreatic microsomal membranes were added to the system. This addition resulted in the formation of a vertical row of three additional spots, with the same isoelectric point as the primary translation product and with molecular masses ranging from 27 to 31 kDa. The 31-kDa protein was retained on Concanavalin A. After digestion with endoglycosidase H, it was no longer visible on sodium dodecyl sulfate gels and a new 27-kDa band was generated suggesting that the mature protein was indeed a glycoprotein. Future experiments will be aimed at identifying this protein and examining its potential value as a marker of renal cell carcinoma.

Carcinoma, Renal Cell↗
PubMed1991

Chronic copper poisoning in two Holstein cows.

Chronic copper poisoning with an acute hemolytic crisis is described in 2 mature Holstein dairy cows from separate herds. Toxic concentrations of copper were present in the serum and in liver and kidney tissues of each cow. There was no history of environmental or dietary exposure to excessive quantities of copper. No further clinical cases of chronic copper toxicosis were observed in the herds. As well as massive hemolysis, in both cows there was involvement of other organ systems including the liver and kidneys which contributed to the clinical course of the disease.

Animals↗
PubMed1990

Effects of androgen and antiandrogen treatment on canine prostatic arginine esterase.

A series of experiments were conducted to investigate the regulation of the primary secretory protein of the canine prostate, arginine esterase, by androgens and/or new antiandrogen under development. In the first experiment, castration decreased (P less than 0.05) prostatic arginine esterase levels relative to intact controls (0.26 +/- 0.1 and 17.0 +/- 0.1 mumole/min/mg protein, respectively). Treatment of castrate dogs with either 5, 10, or 20 silastic capsules (8 cm length) containing the androgen 5 alpha-androstane-3 alpha, 17 beta-diol (3 alpha-diol) plus 1 capsule containing estradiol-17 beta (E2) or the i.m. injection of 25 mg 3 alpha-diol and 0.25 mg E2 for 12 weeks resulted in a dose-dependent increase (P less than 0.05) in prostatic arginine esterase activity (6.8 +/- 1.7, 19.0 +/- 3.6, 21.3 +/- 0.9, and 14.2 +/- 0.7 mumole/min/mg protein, respectively). In the second experiment, steroid treatment (10 3 alpha-diol plus 1 E2 silastic capsules) of castrate dogs for 12 weeks resulted in prostatic arginine esterase activity of 17.8 +/- 2.3 mu mole/min/mg. Co-administration of the steroidal androgen receptor antagonist. Win 49,596 (WIN) at doses of 0.625, 2.5, 10, or 40 mg/kg/day p.o., dose-dependently inhibited (P less than 0.05) prostatic arginine esterase activity (14.9 +/- 1.1, 14.3 +/- 1.3, 3.4 +/- 1.9, and 0.21 +/- 0.1 mumole/min/mg, respectively) to levels similar to that observed in castrate controls (0.14 +/- 0.03 mumole/min/mg). Administration of the nonsteroidal androgen receptor antagonist flutamide at 10 mg/kg/day p.o. to steroid-induced dogs also inhibited (P less than 0.05) arginine esterase activity (0.07 +/- 0.02 mumole/min/mg). In the last experiment, treatment of intact dogs with WIN at 0.625, 2.5, 10, and 40 mg/kg/day for 16 weeks dose-dependently reduced (P less than 0.05) arginine esterase levels (17.0 +/- 1.0, 16.3 +/- 1.5, 10.2 +/- 1.2, and 3.9 +/- 2.5 mumole/min/mg, respectively) compared to intact controls (14.4 +/- 1.2 mumole/min/mg). Histomorphologic and ultrastructural evaluation of prostates from dogs indicated that antiandrogen treatment resulted in glandular epithelial atrophy as well as a reduction in the number of secretory granules. The results of these experiments support that canine prostatic arginine esterase activity is under androgenic control, can be inhibited by antiandrogen treatment and may serve as a functional marker of the androgenic state of the prostate. Whether the effects of androgen and antiandrogens on prostatic arginine esterase is direct or indirect due to a general inhibitory effect on secretory epithelial cell function requires additional study. Furthermore, subject to further evaluation, the steroidal androgen receptor antagonist.(ABSTRACT TRUNCATED AT 400 WORDS)

5-alpha Reductase Inhibitors↗
PubMed1990

Combined use of oligo(dt) and 28S cDNA probes for the quantitation of total mRNA in polyribosomes: application to the castration-induced atrophy of the rat prostate.

The castration-induced atrophy of the rat prostate was used as a model for the validation of a sensitive technique allowing the quantitation of total mRNA in polyribosomes. Electron micrographs of polyribosome samples showed a decrease in polyribosomes length 7 days after castration (GDX). Specificity of labeled oligo(dt) probe for poly(A) was demonstrated and the technique was successfully applied to demonstrate that GDX is associated with a decrease in poly(A) mRNA content of polyribosomes. Provided that normalization of the hybridization signal for mRNA is achieved with a rRNA cDNA probe, the assay therefore represents a suitable tool for further studies regarding the translational regulation of total and/or specific mRNAs.

Animals↗
PubMed1990

Southern blot analysis with synthetic oligonucleotides. Application to prostatic protein genes.

1. An ethanol precipitation procedure was developed to purify radiolabeled DNA and oligonucleotide probes to be used in Southern blots. 2. The radiolabeled probes produced strong hybridization signals on a clear background on Southern blot analysis of single gene copies even after 5 days of exposure on X-ray films. 3. An oligonucleotide probe complementary to human glandular kallikrein-1 coding region (amino acids 161-167) detected a single DNA fragment after digestion with Bam H1, Hind III or Pst 1. 4. Another oligonucleotide probe coding for the same region of human prostate-specific antigen detected 3 DNA fragments on Southern blots by contrast to a 1.5 kb full length cDNA probe which detected the presence of only one strong hybridization signal. 5. Oligonucleotide probes appear to be excellent tools for gene mapping. Their sensitivity, specificity and limitations can be compared to the one of monoclonal antibodies used in epitope mapping of proteins.

Antigens, Neoplasm↗