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B A Matheson

Publications and source records attributed to B A Matheson.

11 recordsLinked to original sources
PubMed1990

Tissue-specific regulation of the expression of rat kallikrein gene family members by thyroid hormone.

We have altered the thyroid hormonal status of both male and female rats and examined the expression of six functional members of the rat kallikrein gene family (PS, S1, S2, S3, K1 and P1) in the submandibular gland (SMG), kidney, prostate, testis and anterior pituitary gland (AP) of these animals. On Northern-blot analysis with gene-specific oligonucleotide probes, the steady-state mRNA levels of S1, S2, S3, K1 and P1 were all dramatically altered in the SMG of male and female rats treated with propylthiouracil (PTU; 100 mg/litre of drinking water) or thyroxine (T4; 10 micrograms/100 mg body wt.) for 3 weeks. The SMG mRNA levels of these five genes were all lowered (30-90%) in hypothyroid (PTU-treated) male and female rats and elevated (1.4-4-fold, male; 1.5-11-fold, female) in the hyperthyroid (T4-treated) and PTU/T4-treated animals. In contrast, PS (true kallikrein) mRNA levels in the male or female SMG or kidney were essentially unchanged. K1 mRNA levels in the kidney were considerably less responsive to thyroid status than those in the SMG. Changes in S3 and P1 mRNA levels in the prostate were also variable, but essentially unaffected by these treatments. AP PS mRNA levels were also unaffected by changes in thyroid-hormonal status, as were levels of a novel P1-like mRNA in the testis. In summary, these studies demonstrate that the same kallikrein gene family member(s) may be differentially regulated by thyroid hormones in the rat SMG, kidney, prostate and pituitary, and thus further extend the concept of tissue-specific expression and hormonal regulation of the kallikrein gene family in the rat.

Animals↗
PubMed1990

Tissue-specific developmental expression of the kallikrein gene family in the rat.

Using a series of gene-specific oligonucleotide probes, we have explored the developmental pattern of expression of six members of the rat kallikrein gene family (PS, S1, S2, S3, K1, and P1) in the submandibular gland (SMG) and kidney of both sexes, the prostate and testis of the male, and the anterior pituitary gland (AP) of the female rat. PS (true kallikrein) mRNA was detected in early neonatal life in the SMG and kidney of both sexes. K1, a second kallikrein gene family member expressed in the adult kidney, had a developmental pattern similar to PS in the kidney. In contrast, tonin (S2), S3, K1, and P1, all of which are expressed in the adult SMG, did not reach detectable SMG mRNA levels until puberty in either the male or female rat. Both S3 and P1, which are expressed in the adult prostate, and the novel P1-like mRNA previously detected in the adult rat testis, first appeared in early puberty. In the female AP, PS mRNA levels were not detected until early puberty and thus exhibited a developmental profile different from that of prolactin. The demonstration that S1, S2, S3, P1, and K1 are not expressed in the SMG or prostate until puberty is consistent with the expression of these genes in these tissues being androgen-regulated; the first appearance of PS mRNA in the female AP in early puberty similarly reflects the estrogen dependence of PS gene expression in this tissue. The presence of PS mRNA levels in the SMG and kidney prior to sexual maturation reflects the androgen independence of PS gene expression and suggests that PS (true kallikrein) may play a constitutive and/or developmental role in SMG or renal physiology.

Animals↗
PubMed1990

Oestrogen administration and the expression of the kallikrein gene family in the rat submandibular gland.

Using a series of oligonucleotide probes (18-21 mers) specific for members of the rat kallikrein/tonin (arginyl-esteropeptidase) gene family (PS, S1, S2, S3, K1, P1), we have shown by Northern blot analysis that all six genes are expressed in the submandibular gland (SMG), with PS (true kallikrein) the most abundant in both male and female rats. Though female levels of PS mRNA are similar to that in the male, levels of mRNA from both the kallikrein-like (S1, K1, P1) and tonin (S2)/tonin-like (S3) genes are all substantially lower in the female than in the male rat. In contrast with the oestrogen dependence of anterior pituitary kallikrein (PS) gene expression, oestrogen administration (6 micrograms/day for 8 days) to castrate male or female rats is without effect on PS or S1, S2, S3, K1, P1 mRNA levels in the SMG. These findings suggest a tissue-specificity in the oestrogen regulation of true kallikrein gene expression in the two tissues. In intact male rats, oestrogen administration lowers SMG levels of S1, S2, S3, K1, and P1 but not PS mRNA to castrate levels, presumably by suppression of the pituitary/gonadal axis, consistent with the previously reported androgen dependence of SMG expression of these genes with the exception of PS.

Animals↗
PubMed1990

Assessment of rapid ELISA test for detection of Epstein-Barr virus infection.

A rapid test for the detection of IgM and IgG Epstein-Barr nuclear antigen (EBNA-1) has been extensively marketed. If IgM to Epstein-Barr viral capsid antigen (EBV VCA) is taken as evidence of current EBV infection, one observer detected 17 of 38 such samples and the other 22 of 38 as acute. The positive predictive value of the test was 63%, and the greatest difficulty was posed by the detection of IgM EBV VCA positive, heterophile antibody negative samples. Significant false positive results were obtained in sera with evidence of current Toxoplasma gondii, cytomegalovirus, and adenovirus infection. Rheumatoid factor was not a problem. Modification of the test protocol improved its performance: the positive predictive value rose to 87% and the negative predictive value to 81%. Although our modifications did not increase the speed of the test, there was reliable information on the EBNA-1 state. The test is best used as an adjunct to other EBV serology, and laboratories should be aware of the limitations of the rapid test.

Antigens, Viral↗
PubMed1989

Kallikrein-gene expression in the rat gastrointestinal tract.

The serine proteinase glandular kallikrein has been demonstrated in the gastrointestinal tract, although there is some doubt as to whether it is synthesized there or derives from exocrine-gland secretions. Using a rat pancreatic kallikrein cRNA probe we have demonstrated kallikrein-like gene expression in the corpus, duodenum, jejunum, ileum, caecum and colon, and compared the pattern of expression with that of the gastrointestinal peptides somatostatin, gastrin and glucagon. In addition, using a panel of oligonucleotide probes specific for various members of the rat kallikrein-gene family, we have shown that the kallikrein-like gene expressed appears to be expressed as true kallikrein.

Animals↗
PubMed1988

Androgen dependence of specific kallikrein gene family members expressed in rat prostate.

We have used oligonucleotide probes specific for members of the rat kallikrein/tonin gene family (PS, S1, S2, S3, K1, and P1) to establish which arginyl esteropeptidase (kallikrein-like) genes are expressed in the prostate. We have also compared the expression and androgen dependence of these genes in prostate, submaxillary gland (SMG) and kidney. Only S3 (tonin-like) and P1 (kallikrein-like) are expressed in the prostate, with S3 very much more abundant. Prostatic S3 mRNA disappears after 8 days castration and is restored to intact levels by dihydrotestosterone (DHT) but not estradiol benzoate (EB) for 8 days. Prostate P1 mRNA levels were similarly but not identically affected. All six genes are expressed in the SMG, with PS (true kallikrein) the most abundant. Levels of PS mRNA in SMG are unaffected by castration, DHT, or EB treatment, although mRNA levels of other kallikrein-like (S1, K1, and P1), tonin (S2), and tonin-like (S3) genes fall 40-60% after castration, and are unaffected or partially restored by DHT and/or EB administration. Only PS and K1 are expressed in the kidney, at much lower levels than in the SMG and unaffected by castration or steroids. These studies thus confirm and extend the concept of tissue specificity of arginyl esteropeptidase gene expression, and further demonstrate that the same gene(s) is differentially regulated by androgens in the rat prostate, SMG, and kidney.

Animals↗
PubMed1988

Kallikrein gene expression in estrogen-induced pituitary tumors.

Anterior pituitary kallikrein-like enzyme activity, immunoreactivity and mRNA levels have previously been shown to be regulated by estrogen, in parallel with prolactin. In this study, we have examined the relationship between kallikrein and prolactin mRNA levels in estrogen-induced pituitary tumors. Treatment of Fischer 344 rats with diethylstilbestrol implants for 3, 5 and 7 weeks produced a dramatic increase in kallikrein mRNA levels and a modest increase in prolactin mRNA levels. These changes were partially reversed by bromocriptine treatment, and completely reversed by bromocriptine plus estrogen withdrawal. Using a panel of oligonucleotide probes specific for various members of the rat kallikrein gene family, we have shown that the kallikrein-like gene expressed appears to be true kallikrein.

Animals↗
PubMed1985

Abortion due to infection with Chlamydia psittaci in a sheep farmer's wife.

A farmer's wife who had helped with lambing aborted spontaneously in March after a short febrile illness in the 28th week of her pregnancy. She developed disseminated intravascular coagulation post partum with acute renal failure and pulmonary oedema. Recovery was complete after two weeks of hospital care. A strain of Chlamydia psittaci, probably of ovine origin, was isolated from the placenta and fetus. The patient's serum showed rising titres of antibody against chlamydia group antigen; the placental and fetal isolates; and a known ovine abortion, but not a known avian, strain of C psittaci. IgG against both ovine abortion and enteric strains of C psittaci was detected, but IgM against only an abortion strain was detected. Histological examination showed pronounced intervillus placentitis with chlamydial inclusions in the trophoblast but no evidence of fetal infection or amnionitis. Laboratory evidence of chlamydial infection was found in an aborting ewe on the farm in January and in remaining sheep and lambs in July. Doctors should recognise the possible risk to pregnant women in rural areas where chlamydial infections in farm animals are widespread.

Abortion, Spontaneous↗