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Biomedical subjects

B A Morris

Publications and source records attributed to B A Morris.

At least 73 records · Page 4Linked to original sources
PubMed1987

Active immunization of cattle against partly purified follicular fluid from sheep.

Yearling cross-bred heifers were injected with 0.4 or 4 mg total protein in non-ulcerative Freund's adjuvant (Groups A and C, respectively; N = 5 per group), or adjuvant with C. parvum (Groups B and D, respectively; N = 5 per group). Control heifers were not treated (N = 9). No antibodies were detected in heifers in Groups A and C and so these were excluded from the analysis. There was no effect of the treatment on Group B or D heifers after the priming or first booster injection. After a second booster injection one Group D heifer gave a triple ovulation, and two Group D heifers and one Group B heifer gave double ovulations, but for one oestrous cycle only. Group B heifers also showed a significant rise in FSH concentrations after the second booster injection. Group D heifers were given a third booster injection; there was an increase in the mean number of large follicles per heifer, and a decrease in oestrous cycle length, but no increase in ovulation rate. These results indicate that a transient increase in ovulation rate can be induced by actively immunizing cattle against partly purified follicular fluid from sheep.

Animals↗
PubMed1987

Preparation of a bovine monoclonal antibody to testosterone by interspecies fusion.

This communication reports the first successful attempt to produce a hybridoma cell line secreting bovine immunoglobulin to a small hapten, starting with peripheral blood lymphocytes, rather than spleen or lymph node cells. A heteromyeloma line, sensitive to selective media, was made by fusing NS1/1-Ag4-1 mouse myeloma cells with bovine peripheral blood lymphocytes. This cell line was then fused with blood lymphocytes from a steer immunised with a testosterone immunogen. Cell cultures were screened using an ELISA specific for bovine antibodies to testosterone. Following repeated cloning, a cell line was established which secretes moderate levels of a specific, high affinity antibody to testosterone. This particular cell line has significant potential for veterinary application and the successful fusion demonstrates the possibilities of heteromyelomas for the development of non-murine monoclonal antibodies.

Animals↗
PubMed1986

Medical response to a natural disaster: the Barrie tornado.

On May 31, 1985, a tornado devastated an area of Barrie, Ont. Following a prepared disaster plan, the staff of the local hospital managed 155 casualties, including 16 cases of multiple trauma, over 5 hours. The authors summarize the hospital's experience and give recommendations to help the staff of other hospitals improve their disaster plans.

Disaster Planning↗
PubMed1986

Immuno-neutralization of maternal plasma oestradiol stimulates fetal growth in rats.

On day 12 of pregnancy, 7 rats were injected with 2 ml of an anti-oestradiol antiserum a quantity capable of binding 2.4 micrograms oestradiol. Seven further (control) rats were injected with an antiserum raised against human serum globulin. After sacrifice on day 21 of pregnancy, the fetuses from treated rats showed an increase in both placental weight (0.851 +/- 0.023 g, n = 98 vs 0.752 +/- 0.019 g, n = 97) and fetal weight (4.446 +/- 0.426 g, n = 98 vs 3.403 +/- 0.211 g, n = 97). There was no significant difference in protein, DNA and RNA contents between the fetuses from treated mothers and those from control mothers. This experiment confirms that oestrogens may play a role in fetal weight gain.

Animals↗
PubMed1986

Potato steroidal alkaloids and neural tube defects: serum concentrations fail to demonstrate a causal relation.

Spoiled potatoes and, in particular, steroidal alkaloids have been proposed as an aetiological factor in the pathogenesis of neural tube defect (NTD). The present study involves the measurement of potato (solanum) steroidal alkaloid concentrations in serum by radioimmunoassay. Serum solanidine and total potato alkaloid concentrations were measured in two groups of women: one group pregnant with a fetus, subsequently shown to be affected by a NTD, the other with a healthy fetus. Serum alkaloid concentrations were, contrary to expectations, lower in the NTD group. They lend no weight therefore to the theory that potato alkaloids are responsible for NTD, but are consistent with the opinion that some water-soluble vitamins lessen the risk.

Diosgenin↗
PubMed1986

Use of progesterone 11-glucuronide-alkaline phosphatase conjugate in a sensitive microtitre-plate enzymeimmunoassay of progesterone in milk and its application to pregnancy testing in dairy cattle.

A simple direct-addition microtitre plate enzymeimmunoassay (EIA) for progesterone in whole milk is described. The assay used antiserum raised against 11 alpha-hydroxyprogesterone 11-hemisuccinate (progesterone 11-hemisuccinate) and a heterologous label prepared by conjugation of 11 alpha-hydroxyprogesterone 11-glucuronide (progesterone 11-glucuronide) with alkaline phosphatase using an active ester procedure. The sensitivity, analytical recovery, linearity of response and precision of the assay compared favourably with radioimmunoassay (RIA). Results from EIA of milk samples were compared with determinations made after isolation of progesterone by HPLC (r = 0.910). Milk samples (200) were assayed by RIA at both the Milk Marketing Board and the Cattle Breeding Centre and the results were correlated with EIA performed at the Cattle Breeding Centre (r = 0.890 and r = 0.833 respectively). Calving data were obtained from a further 110 cows for which the milk progesterone EIA had provided a pregnancy test 24 days after AI; 46 cows were correctly identified as non-pregnant and 58 as pregnant and there were 4 false positive and 2 inconclusive results.

Alkaline Phosphatase↗
PubMed1986

Effects of passive immunization against oestradiol-17 beta on some endocrine values of the male lamb.

Passive immunization of male lambs against oestradiol-17 beta from 2 to 16 weeks of age significantly elevated androgen concentrations in plasma and depressed the median eminence content of dopamine. Removal of endogenous oestrogens had no significant effects on plasma FSH, LH or prolactin concentrations or on testicular growth and hypothalamic content of GnRH. These results suggest that endogenous oestrogens may indirectly suppress testicular androgen secretion by exerting a stimulatory influence on hypothalamic dopaminergic neurones, which in turn may inhibit GnRH secretion by the median eminence.

Androgens↗
PubMed1985

Measurement of potato steroidal alkaloids in human serum and saliva by radioimmunoassay.

Radioimmunoassay methods are described for measuring potentially toxic potato glycoalkaloids and the aglycone solanidine in human serum and saliva. Solanidine and total alkaloid concentrations in serum and saliva during the summer are given for a group of subjects from the UK and a group from Sweden. Serum concentrations ranged from 3.2 to greater than 125 nmol/l for total alkaloid and 2.5 to 92.5 nmol/l for solanidine and were comparable in the two populations. Salivary total alkaloid concentrations were only about 10% of serum values. Salivary solanidine concentrations did not exceed 20% of the serum levels. Good correlation was found between serum and salivary alkaloid concentrations (r = 0.734, for solanidine; r = 0.892 for total alkaloid). Serum and salivary alkaloid concentrations were significantly raised in a group of Swedish subjects eating potatoes containing unusually high concentrations of alkaloids when compared with those in a group of subjects eating their normal diets.

Adult↗
PubMed1984

Concentration of gonadotrophins in the plasma of sheep given gonadal steroid antisera to raise ovulation rate.

The concentration of FSH and LH in peripheral plasma was studied in sheep from 8 h before to 17.5 h after injection (i.v.) with antisera to the steroids androstenedione, oestradiol, oestrone and testosterone. The fitted mean concentration of LH increases after all treatments and the increase was associated with a higher frequency of LH pulses. The greater concentration was evident for all groups by the period 3.5-6.5 h after injection, but by the end of the sampling period the concentration had returned to or towards the values in the controls. For FSH, significant change was limited to those animals given anti-oestrogen sera but it was more rapid than for LH, both groups receiving anti-oestrogen sera showing an increase during the period 0.5-3.0 h after injection. The ovulation rate was increased by treatment and an effect close to 0.75 corpora lutea per ewe was maintained by treatment in subsequent oestrous cycles. This declined to 0.25 corpora lutea after two oestrous cycles without treatment.

Androstenedione↗
PubMed1983

Fertility of sheep given antisera to steroids during anoestrus.

The incidence of oestrus (6/46) and ovulation (14/46) in ewes given antisera to androstenedione, oestrone, oestradiol and testosterone either separately or as a mixture of these sera at the time of treatment with progestagen sponges alone or progestagen sponges followed by LH-RH was similar to that of control ewes (2/13 and 6/13 respectively). The number of corpora lutea (CL) recorded for those ewes that did ovulate was, however, greater in the antiserum-treated ewes (22 CL/14 ewes) than in the controls (6 CL/6 ewes) at the first ovulation after sponge withdrawal. This superiority persisted to the second ovulation (53 CL/42 treated ewes compared to 13 CL/13 controls). The results for groups treated with antisera did not differ amongst themselves.

Androstenedione↗
PubMed1982

Improvement of sheep fecundity by treatment with antisera to gonadal steroids.

Sera from sheep immunized against oestrone (Group E1), oestradiol (Group E2), androstenedione (Group A) and testosterone (Group T) were given to ewes singly or as a mixture (Group M) of all 55 types as a single intravenous injection at the time of the start of mating. The number of lambs produced, the numbers of eggs shed and the display of oestrus were recorded. The ovulation rates were 1.8 in Group E1, 2.1 in Group E2, 1.6 in Group A, 1.8 in Group T and 2.1 in Group M compared with 1.3 for the controls (P, variation among groups, less than 0.001) in the first oestrous cycle. The effect persisted in those animals not conceiving to the first mating--1.3 in Group A, 1.8 in Group E1, 1.9 in Group E2 and 2.0 in Group M compared with 1.3 for the controls; all of the ewes in Group T conceived to mating at a single oestrus. The mean number of lambs born alive per ewe treated was 1.1 for Group A, 1.3 for Group E1, 1.3 for Group E2, 1.5 for Group T, 1.5 for Group M and 1.0 for the controls. The increase in the number of lambs born was due to a higher proportion giving birth to twins (P less than 0.01); no ewe gave birth to triplets. High conception rates were recorded for all treatments.

Androstenedione↗
PubMed1979

Gastroesophageal reflux among severely retarded children.

Of 136 institutionalized severely retarded children, 20 (15%) had recurrent vomiting. Of these 20, 15 had gastroesophageal reflux diagnosed by x-ray examination, acid reflux text, or both. Esophagitis was noted by endoscopy in ten of 14 patients with GER. Four patients were anemic and six had had one or more episodes of aspiration pneumonia in the 12 months prior to study. Reduced basal lower esophageal sphincter pressure was the most common manometric abnormality noted in the patients with GER. Responses of the LES to bethanechol and swallow were normal, as was the basal pressure of the upper esophageal sphincter. Abnormal propagation of esophageal peristalsis was seen in six patients, all of whom had moderate or severe esophagitis. When compared to the nonvomiting retarded patients, the GER patients had significantly lower mental age and higher incidence of scoliosis. Patients with GER who had basal LES pressure less than 10 mm Hg did not improve with medical management. Recurrent vomiting is a common and serious problem in severely retarded children, the organic cause of which can be demonstrated by the application of appropriate investigative techniques.

Adolescent↗
PubMed1978

Radioimmunoassay of gastric inhibitory polypeptide.

A radioimmunoassay for the measurement of gastric inhibitory polypeptide (GIP) in unextracted plasma in man has been developed using a rabbit antiserum raised against porcine GIP. Porcine GIP was employed also as standard and to produce a 125I-labelled tracer. The assay was able to distinguish 110 pg/ml GIP from zero in plasma samples. Negligible cross-reactivity was demonstrated with cholecystokinin, insulin, pancreatic polypeptide, glucagon, secretin, and vasoactive intestinal polypeptide. The mean overnight fasting plasma GIP level in 28 normal subjects was 203 pg/ml (range: undetectable--420 pg/ml). Plasma GIP levels rose, within 45 minutes of eating a mixed meal, to a mean level of 1573 pg/ml.

Animals↗
PubMed1975

Pharmacokinetics of a single dose of phenytoin in man measured by radioimmunoassay.

1. Serum concentrations of phenytoin were studied by radioimmunoassay in five normal volunteers following a single oral dose of phenytoin sodium (100 mg). 2. Two distinct peaks were found at 2.5-3.5 and 10-12 h after ingestion. Maximum serum concentrations ranged from 1.56 mug/ml. The mean plasma half-life of the drug under these conditions was 9.81 +/- 0.66 (s.e. mean) hours.

Administration, Oral↗
PubMed1975

Development of a radioimmunoassay for etorphine (preliminary communication).

A radioimmunoassay for etorphine has been developed using antibodies raised in a rabbit against an etorphine-3-hemisuccinate-bovine serum albumin conjugate. Using tritiated etorphine as the label, the antiserum could be used at a final dilution of 1:4 and had an avidity of 1.8 times 10-9 L.M.-1. The sensitivity of the assay was 0.88 plus or minus 0.04 ng etorphine per ml of serum and there was no cross-reactivity with any of the six opiate alkaloids examined over the range 0-100 ng/ml.

Animals↗