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Biomedical subjects

J D Olson

Publications and source records attributed to J D Olson.

At least 91 records · Page 5Linked to original sources
PubMed1983

Bovine genital campylobacteriosis (vibriosis): vaccination of experimentally infected bulls.

The therapeutic efficacy of a Campylobacter fetus subsp venerealis bacterin was determined in experimentally infected bulls. Ten of twelve 5-year-old Angus bulls became infected after being infused intrapreputially with C fetus subsp venerealis. Of the 10 bulls, 6 were vaccinated with 5 ml of C fetus subsp venerealis vaccine on 2 occasions 4 weeks apart. Preputial washings of the vaccinated bulls were culturally negative by the 8th week after primary vaccination. None of the 18 heifers exposed to the vaccinated bulls became infected. The 4 infected, nonvaccinated bulls remained culturally positive to C fetus (P less than 0.002), and each bull infected at least 1 heifer (P less than 0.001). Two noninfected, nonvaccinated bulls remained culturally negative and did not infect any heifer. The 4 infected, nonvaccinated bulls were then vaccinated. Two bulls remained infected 9 weeks after primary vaccination, as determined by the virgin heifer test and cultural examination of preputial washings. Serologic data from 7 sampling periods were different (P less than 0.001) for vaccinated vs nonvaccinated bulls at 4 (against K antigen) or 6 (against O antigen) weeks after primary vaccination. Vaccination was effective in eliminating the infection in most of the infected bulls, but cannot be recommended as the sole measure of control in infected herds.

Animals↗
PubMed1982

Concentrations of reproductive hormones in canine serum throughout late anestrus, proestrus and estrus.

Concentrations of estradiol, progesterone, luteinizing hormone (LH), follicle-stimulating hormone (FSH) and prolactin in serum from 6 bitches bled daily for at least 45 days before the onset of proestrus, during proestrus and estrus were determined by radioimmunoassay. Mean concentrations of estradiol in serum were high early in the sampling period (20 to 46 pg/ml) and appeared to decrease prior to the onset of proestrus (8 to 19 pg/ml). There were sporadic increases in serum concentrations of LH throughout the sampling period in each bitch. Five of the 6 bitches sampled had increased serum concentrations of LH following the low mean concentration of estradiol just before the onset of proestrus. Mean concentrations of FSH were highest during anestrus (240 to 294 ng/ml) and near the time of the preovulatory surge of LH (297 ng/ml) and were lowest during proestrus (131 to 200 ng/ml). The mean concentration of progesterone for the 6 bitches remained at less than 1.0 ng/ml throughout late anestrus, but increased to greater than 1.0 ng/ml the day of the maximum mean concentration of LH (preovulatory LH surge). Mean concentrations of prolactin were variable throughout the sampling period and demonstrated no consistent pattern among bitches. The results of the current investigation suggest that neither the canine ovary nor pituitary are quiescent during anestrus. The bitch appears to have sufficient FSH present during anestrus for follicular growth. Serum concentrations of LH appear to increase prior to the onset of proestrus when concentrations of estradiol are lowest, possibly inducing a new follicular phase. Progesterone and prolactin do not appear to be involved in the termination of anestrus in the bitch.

Anestrus↗
PubMed1981

Serum chloramphenicol concentrations in preruminant calves: a comparison of two formulations dosed orally.

Serum concentrations of chloramphenicol were determined after oral doses (55 mg/kg body weight) were administered to 7-9 day old Holstein-Friesian calves. Chloramphenicol in an oral solution produced greater serum concentrations than did an equivalent dose of chloramphenicol in capsules (P less than 0.005). A second dose of each formulation administered 12 h after the first dose elevated serum chloramphenicol concentrations significantly (P less than 0.001). The average serum chloramphenicol concentration exceeded 5 micrograms/ml of serum 1 h after administration of the solution compared with 4 h for the capsules. Average serum chloramphenicol concentration was greater than 5 micrograms/ml for at least 12 h after the dose was administered for both formulations. Of the eight calves receiving repeat doses of chloramphenicol, seven (87.5%) developed diarrhea in 76 +/- 8.6 h. Six of the eight calves (75%) died during or shortly after the period of chloramphenicol administration.

Administration, Oral↗
PubMed1981

Platelets, von Willebrand factor, and prostaglandin I2.

Depending on the time of addition, prostaglandin I2 (PGI2; greater than or equal to 10(-9) M) either inhibits or reverses platelet agglutination mediated by human factor VIII-related von Willebrand factor activity (FVIIIvWF) and ristocetin, or bovine FVIIIvWF alone. 6-Keto-PGF1 alpha, the inactive metabolite of PGI2, is without effect, PGI2 inhibition is potentiated by the phosphodiesterase inhibitor, theophylline, and is not the result of PGI2 suppression of ADP release. PGI2 (+/- theophylline) does not inhibit ristocetin-induced binding of purified human 125I-FVIIIvWF multimers to washed platelets or to platelets treated with PGI2 and then formalin fixed (although subsequent agglutination of these platelets is impaired). Washed platelets treated previously with 2-aminoethylisothiouronium bromide (AET), an agent that reduces disulfide bonds and alters platelet membranes, also bind human 125I-FVIIIvWF multimers without agglutinating. We conclude that FVIIIvWF-mediated agglutination requires both functional platelet FVIIIvWF binding sites and platelet-platelet cohesion sites, and that platelet surface cohesion sites are altered by AET and PGI2. PGI2 from adjacent intact endothelial cells may prevent excessive platelet accumulation on exposed subendothelium without suppressing an essential hemostatic process--the binding of platelets to subendothelial FVIIIvWF.

Animals↗
PubMed1981

Type IIB von Willebrand's disease: unusual response to cryoprecipitate infusion.

A 16-year-old boy had IIB von Willebrand's disease. The disorder is characterized by prolonged bleeding times; normal plasma levels of factor VIII-coagulant activity, factor VIII-ristocetin cofactor activity, and factor VIII-related antigen; abnormal (anodal) mobility of plasma factor VIII-related antigen on two-dimensional crossed immunoelectrophoresis; and enhanced binding of plasma factor VIII-related antigen to normal platelets in the presence of ristocetin. These variables were measured at time periods after an infusion of normal cryoprecipitate into the patient. The electrophoretic mobility of his plasma factor VIII-related antigen was normal 15 minutes after the infusion but became abnormal (anodal) by 4 hours. His bleeding times were normal after 24 hours and did not correlate with plasma levels of factor VIII-coagulation activity, factor VIII-ristocetin cofactor, factor VIII-related antigen, or the electrophoretic mobility of his plasma factor VIII-related antigen. These results imply that the abnormal factor VIII/von Willebrand factor multimers in the plasma of these patients can associate with normal factor VIII/von Willebrand factor multimers and delay the deposition of the normal multimers into subendothelial surfaces. This may require cryoprecipitate infusions 24 hours before elective surgical procedures.

Adolescent↗
PubMed1981

The effect of PGI2 and theophylline on the response of platelets subjected to shear stress.

A specially designed rotational viscometer was used to investigate the effects of the antiplatelet agent PGI2 in combination with theophylline on the response of human platelets subjected to shear stress. Samples of citrated platelet-rich plasma (PRP) were exposed to shear stress in the viscometer for a period of 5 min at 23 degrees C. The levels of stress studied ranged from 50 to 300 dynes/sq cm. Pretreatment of the platelets with 0.01 microM PGI2 and 500 microM theophylline before exposure to shear stress caused a large reduction in shear-induced platelet aggregation. However, it was also observed that the PGI2--theophylline pretreatment concomitantly caused a large increase in shear-induced platelet lysis and serotonin release at stress levels equal to or greater than 150 dynes/sq cm. This observed increase in platelet fragility may have important implications for clinical applications of PGI2. The results are discussed and compared to those obtained in prior work in which platelets were pretreated with acetylsalicylic acid or with PGE1.

Adenosine Diphosphate↗
PubMed1981

Plasma cell myeloma of the orbit.

An 80-year-old woman had a left superior temporal orbital mass that displaced the globe downward and forward. Restriction of motion was present in all fields of gaze. Radiologic and ultrasound evaluation revealed an orbital mass extending posteriorly, with erosion of the superior orbital rim. Biopsy diagnosis was plasma cell myeloma, a rare orbital tumor. The patient was subsequently found to have multiple myeloma, treated with local radiotherapy and chemotherapy. Three-and-one-half years after diagnosis, she is alive and in remission.

Aged↗
PubMed1980

Comparison of treatment of pyometra with estradiol cypionate or cloprostenol followed by infusion or non-infusion with nitrofurazone.

One hundred-fifty-two dairy cows affected with pyometra were treated either with cloprostenol (CLP) or with estradiol cypionate (ECP). The cows which failed to respond within 7-10 days were re-treated with the same drug used in the first treatment. Half of the cows which responded to these treatments received intrauterine infusions with 50 cc nitrofurazone solution. After two treatments, 72 (94.9%) of 79 cows in the CLP group had evacuated the purulent exudate from their uteri whereas only 57 (78.1%) of 73 cows in the ECP group had responded (P<0.005). Treatment-to-breeding and treatment-to-conception intervals were not different between the ECP and CLP groups. The number of services/conception was not different up to the 4th service (3.16 vs 3.57, respectively, P>0.1). Eight (9.3%) of 86 CLP treated and 3 (5.1%) of 59 ECP treated cows had recurrence of pyometra (P>0.1). Incidence of follicular cysts within 30 days after treatment was 16.4% (13 79 ) and 7.0% (4 57 ) among CLP and ECP groups, respectively (P>0.1). Two of 106 CLP (1.9%) and 5 of 107 ECP treatments (4.7%) were associated with subsequent perimetritis and adhesions. Intrauterine infusion of nitrofurazone increased the number of services/ conception (3.57 vs 2.21, P<0.01). Cloprostenol was superior to ECP as an initial treatment of bovine pyometra. Intrauterine infusion of nitrofurazone following evacuation of the uterus appeared not to be effective in prevention of relapses and had a negative effect on conception rates.

Journal Article↗
PubMed1980

Delayed and recurrent intracranial hematomas related to disseminated intravascular clotting and fibrinolysis in head injury.

Twelve delayed or recurrent intracranial hematomas were seen in 340 patients with head injuries. Eleven of these hematomas were associated with clotting abnormalities suggesting disseminated intravascular clotting and fibrinolysis (DICF). Seven of 8 delayed traumatic intracerebral hematomas were associated with clotting abnormalities. Two of these were at ventriculostomy sites, which suggests an increased risk of bleeding in association with the insertion of ventricular catheters in patients with DICF. There were 2 delayed epidural hematomas, 1 under a fracture and the other on the side opposite a craniotomy that had been made to treat an intracerebral hematoma, and there were 2 postoperative epidural hematomas. No postoperative hematomas occurred in the absence of DICF. DICF is a major factor in the development of delayed and recurrent intracranial hematomas in patients with head injuries.

Brain Injuries↗
PubMed1980

Effects on reproductive performance of administration of GnRH to early postpartum dairy cows.

Three-hundred and thirty-five lactating dairy cows from two herds were used to compare the effects on reproductive performance of intramuscular injections of 100 micrograms gonadotropin-releasing hormone (GnRH), 250 micrograms GnRH or saline given on day 13, 14 or 15 postpartum. The incidence of ovarian cysts or uterine infections was not reduced after GnRH injection. Culling rate for infertility did not differ in either herd between GnRH- and saline-treated control cows. In the herd in which breeding began earlier in the postpartum period (Herd B), injection of 250 micrograms GnRH resulted in a better (P < .05) calving to conception interval (81 vs 96 days), better first service conception rate (74.5 vs 56.0%), better overall conception rate (70.6 vs 51.1%) and a lower number of services per conception (1.23 vs 1.74) than in the controls. In reproductively well-managed herds, injections of 250 micrograms GnRH, given to lactating dairy cows 2 weeks after calving, may increase fertility.

Animals↗
PubMed1980

Interaction of platelets, von Willebrand factor, and ristocetin during platelet agglutination.

Ristocetin induces platelet agglutination in the presence of human factor VIII-associated ristocetin cofactor (vWF). The specificity, extent, and tenacity of binding among these reactants during agglutination and deagglutination were examined. Purified human vWF polymers were radioiodinated and reisolated. Radioiodinated vWF, a disulfide-linked polymer of 230,000 dalton subunits, attached to formalinized human platelets only in the presence of ristocetin. This binding reached equilibrium within 30 sec, and as ristocetin concentrations were raised from 0.2 mg/ml, the extent of attachment increased progressively to reach maximum at 0.5 to 0.6 mg/ml ristocetin. Ristocetin-induced binding was inhibited by vancomycin, unlabeled-purified vWF polymers, normal and hemophilia A plasma, and rabbit anti-human vWF. Binding was not impaired by plasma without detectable vWF or by naturally occurring human IgG antibodies to factor VIII coagulant activity. When formalinized platelets were pelleted from suspensions containing 125I-ristocetin, small quantities of radiolabeled ristocetin associated with platelets both in the presence or absence of vWF. About 95% of the attached 125I-ristocetin was removed by subsequent washes in buffered saline. The attachment of unmodified ristocetin or 125I-ristocetin to platelets, or the formation of complexes with vWF, could not be detected by agarose column chromatography, sucrose cushion ultracentrifugation, or equilibrium dialysis. These results indicate that (1) the initial binding of human vWF polymers to platelets is a specific interaction which requires the presence of ristocetin; (2) ristocetin and human vWF do not form persistent complexes in solution; and (3) the association of ristocetin and platelets is of low affinity.

Blood Coagulation Factors↗
PubMed1980

Prothrombin Houston: a dysprothrombin identifiable by crossed immunoelectrofocusing and abnormal Echis carinatus venom activation.

A 72-yr-old male with a lifelong history of easy bruisability and posttraumatic bleeding had a prolonged prothrombin time and activated partial thromboplastin time. His plasma Stypven, Taipan, and Echis carinatus venom clotting times were prolonged. The presence of a dysprothrombin was confirmed by the discrepancy between plasma prothrombin coagulant activity and prothrombin antigen levels. His plasma prothrombin was capable of being completely absorbed onto and then eluted from barium sulfate. Crossed immunoelectrophoresis of his plasma prothrombin, and normal plasma prothrombin, into agarose containing rabbit anti-human factor II antibody were similar. Crossed immunoelectrofocusing, a procedure combining isoelectric focusing in disc gels with electroimmunoassay in the second dimension, demonstrated that the patient's prothrombin antigen was more basic than normal. The eluate from barium sulfate absorbtion of patient plasma, when reacted with Echis carinatus venom (which directly cleaves prothrombin to thrombin) clotted purified fibrinogen at a rate slower than normal plasma eluate. SDS-slab gel electrophoresis revealed that the prothrombin present in the patient's eluate was cleaved by Echis carinatus venom. These studies suggest that the coagulopathy of prothrombin Houston results from the generation of a dysfunctional thrombin.

Aged↗
PubMed1978

Telangiectasia and von Willebrand's disease in two families.

Two families are described with members who have both von Willebrand's disease and telangiectasias. Family A has four members in three consecutive generations that have both von Willebrand's disease and telangiectasias. von Willebrand's disease in this family is characterized by decreased ristocetin cofactor (FVIII-vWF), variably depressed factor VIII coagulant (FVIII-AHG), and factor VIII-related antigen (FVIII-AGN) levels. FVIII-AGN mobility on two-dimensional crossed immunoelectrophoresis was found to be normal. Four generations in Family B have von Willebrand's disease characterized by decreased FVIIII-AHG, FVIII-vWF, FVIII-AGN, and prolonged template bleeding times. Two members of this family also have telangiectasias and recurrent gastrointestinal bleeding. Results in these two families suggest an association between von Willebrand's disease and telangiectasia--perhaps a defect in vascular endothelial cell function.

Adolescent↗
PubMed1977

Purification of porcine and human ristocetin-Willebrand factor.

A plasmatic component required for the ristocetin-induced aggregation of platelets has been purified from normal human and porcine plasma by gel filtration (4% agarose) and anion-exchange chromatography (DEAE cellulose). No factor VIII coagulant activity was found associated with the purified human or porcine component. Urea sodium dodecylsulfate electrophoretic analysis of the purified component of both species indicated that the apparent molecular weight with intact disulfides is in excess of 500,000; after disulfide reduction with 2-mercaptoethanol, single components with an apparent subunit molecular weight of 230,000 were observed. Purified porcine ristocetin-Willebrand factor (RWF) co-sedimented in sucrose gradients with the factor present in normal plasma. Amino acid analysis of both human and porcine RWF indicated that all normal amino acids are present, whereas amino sugars were undetected. However, lipid analysis indicated 1% to 2% lipids present, including monoglycerides, di- and tri-glycerides, cholesterol, cholesterol esters, some free fatty acids, and a trace of phospholipid. A single line of identity was observed between normal human plasma and purified human RWF when immunodiffusion plates were run with purified rabbit anti-human RWF immunoglobulins. Antisera raised against human and porcine RWF's do not inhibit the factor VIII coagulant activity of the homologous plasma, nor is "spontaneously occurring" human factor VIII inhibitor neutralized by the isolated material of either species.

Amino Acids↗
PubMed1976

The spectrum of von Willebrand's disease revisited.

We have examined nine patients with presumed von Willebrand's disease who present the spectrum of that disorder. Two had findings that would be accepted generally as diagnostic of von Willebrand's disease, and seven had variations of the usual pattern. The commonest variation was the combination of borderline and variable levels of coagulant Factor VIII, commensurate levels of Factor VIII-related antigen, and low levels of ristocetin-Willebrand factor.

Adolescent↗