Determination of amino acids and monoamine neurotransmitters in caudate nucleus of seizure-resistant and seizure-prone BALB/c mice

Amino acid and monoamine concentrations were examined in tissue extracts of caudate nucleus of genetic substrains of BALB/c mice susceptible or resistant to audiogenic seizures. Amino acids [aspartate, glutamate, glycine, taurine, serine, gamma-aminobutyric acid (GABA)], monoamines, and related metabolites were separated by isocratic reverse-phase chromatography and detected by a coulometric electrode array system. In situ activity of tyrosine hydroxylase and tryptophan hydroxylase were determined by measuring the accumulation of L-DOPA and 5-hydroxytryptophan after administration of the decarboxylase inhibitor NSD-1015. Highly significant decreases in concentrations of both excitatory (glutamate and aspartate) and inhibitory amino acids (GABA and taurine) were observed in extracts of caudate nucleus of seizure-prone mice. Substantial decreases in concentrations of dopamine (DA) and its metabolites, 3,4-dihydroxyphenylacetic acid and homovanillic acid, were also noted. Decreased accumulation of L-DOPA after NSD-1015 administration provided evidence for decreased tyrosine hydroxylase activity and decreased DA synthesis in striatum of seizure-prone mice compared with seizure-resistant mice. Decreased concentrations of the DA metabolite 3-methoxytyramine (after NSD-1015 administration) suggested that DA release was also compromised in seizure-prone mice. No significant difference in 5-hydroxytryptophan accumulation in striatum of seizure-prone and seizure-resistant mice suggested that tryptophan hydroxylase activity and serotonin synthesis were not affected. The data suggest that seizure-prone BALB/c mice have a deficiency in intracellular content of both excitatory and inhibitory amino acids. The data also raise the issue of whether GABAergic interactions with the nigrostriatal DA system are important in the regulation of audiogenic seizure susceptibility.

Evidence for bimodal distribution of breast carcinoma ER and PgR values quantitated by enzyme immunoassay

Breast carcinoma oestrogen receptor (ER) and progesterone receptor (PgR) values obtained by radioligand binding assays have commonly been observed to have approximate log-normal distributions. We examined the distribution of log-transformed receptor values obtained by enzyme immunoassay for 5468 primary breast carcinomas in five Ontario laboratories. In each laboratory, it was found that the frequency histograms for the log transformed receptor values were not unimodal, and generally were suggestive of bimodality. This was not affected by stratification by age or inferred menopausal status (< or = 49, > or = 50 years), and could not be explained by kit characteristics. However, the low point in the distribution varied from 5 to 63 fmol/mg cytosol protein, depending on the receptor, patient age and laboratory. The tendency towards biomodality was more distinct for ER than for PgR. It remains to be determined whether the low points on the frequency histograms have clinical relevance for discriminating between hormone-sensitive and hormone-insensitive tumours.

The cost of neonatal care

A medical and financial assessment of the Neonatal Unit at Groote Schuur Hospital showed that the emphasis was on high care provided at a cost of R265 per patient per day. Intensive care cost R530 and low care R88 per day. The average was R172 per day. Infants of very low birth weight (< 1,500 g) accounted for 58% of expenditure. Half of this amount was spent on infants of below 1,000 g; the cost was R14 621 per survivor and R344 per quality-adjusted life-year. The cost declined progressively for infants of greater birth weight. There are a paucity of comparable local data, but the cost of the care was very reasonable.

Involvement of excitatory amino acid receptors in long-term potentiation in the Schaffer collateral-commissural pathway of rat hippocampal slices

The present article reviews studies from our laboratory, which have shown that excitatory amino acids receptors of the N-methyl-D-aspartate type are involved in the induction of long-term potentiation in the Schaffer collateral-commissural pathway of rat hippocampal slices. The nature of the excitatory amino acid receptors that mediate the response that is modified by the induction of long-term potentiation is also considered. The mechanism of induction of long-term potentiation is discussed, as are some possible stages that are required for the maintenance of this process. Some new data are presented concerning the ability of N-methyl-D-aspartate to potentiate synaptic transmission and to depress the amplitude of the presynaptic fibre volley. Concerning the potentiation, it is shown that brief (1-2 min) perfusion of slices with N-methyl-D-aspartate is sufficient to potentiate synaptic transmission for at least 3 h. The N-methyl-D-aspartate induced depression of the presynaptic fibre volley is shown to be transient and independent of synaptic transmission.

Unique modulation of central 5-HT2 receptor binding sites and 5-HT2 receptor-mediated behavior by continuous gepirone treatment

The effect of continuous treatment with the selective 5-HT1A agonist gepirone upon 5-HT2-mediated behavior and cortical 5-HT2 receptor binding sites was examined in naive rats or rats receiving noradrenergic (DSP4) or serotonergic (5,7-DHT) lesions. Continuous administration of gepirone in non-lesioned rats for 3, 7, or 14 days enhanced the head shake response to the 5-HT agonist quipazine. This enhancement of 5-HT2-mediated behavior occurred despite concomitant down-regulation of cortical 5-HT2 binding sites. However, 28 days of gepirone administration significantly reduced behavioral responsiveness to quipazine. The gepirone-induced facilitation of 5-HT2-mediated behavior observed after 7 days of continuous treatment was blocked in both DSP4 and 5,7-DHT-lesioned rats. However, both noradrenergic and serotonergic denervation failed to modify the down-regulation of 5-HT2 receptor binding sites produced by continuous gepirone administration. These results suggest that the curious dissociation of behavioral and biochemical indices of 5-HT2 receptor function produced by continuous gepirone treatment may be the result of a dual yet separate action of the drug on central presynaptic noradrenergic and serotonergic mechanisms and postsynaptic 5-HT receptors. Furthermore, the postsynaptic action of gepirone which reduces the maximal number of cortical 5-HT2 receptor binding sites may be the result of gepirone's agonist action at postsynaptic 5-HT1A receptors.

Is there a role for CA-125 in monitoring patients with early endometrial cancer?

Elevated CA-125 levels have been reported in some women with endometrial carcinoma. Current follow-up policy for these patients does not involve the use of tumor markers. CA-125 measurements were performed in 28 patients with a diagnosis of endometrial cancer, 14 clinically free of disease and 14 with known disease. Based on the sensitivity (0.64) and specificity (0.93) observed we constructed a model to estimate the predictive value of the assay as a marker in the follow-up of patients who have completed treatment. This model would involve a CA-125 assay every six months for five years in 100 patients with stage I and II disease. Despite the high statistical correlation between the clinical status of the patient and the CA-125 value observed in our study, the positive predictive value would be approximately 24% in such a follow-up protocol where a low prevalence of recurrent malignancy is expected.

Normoglycaemia after transplantation of freshly isolated and cryopreserved pancreatic islets in type 1 (insulin-dependent) diabetes mellitus

Purified islets of Langerhans and a kidney were transplanted into a 36-year-old patient who suffered from renal failure secondary to a 25 year history of Type 1 (insulin-dependent) diabetes mellitus. The islet graft contained 243,000 fresh islets (mean islet diameter 150 microns) that were syngeneic with the kidney graft and 368000 cryopreserved islets that had been collected from four other donors. The total of 10,000 islets/kg body weight was infused into the liver via the umbilical vein. Immunosuppression was induced with antilymphocyte globulin and maintained with prednisone, cyclosporine and azathioprine. Serum C-peptide levels (ng/ml) during fasting and after standard mixed meal feeding (Sustacal) were less than 0.12 preoperatively. Postoperatively, insulin secretion was restored: fasting C-peptide rose during the first 4 weeks to levels of 4 to 5 and Sustacal elicited a further rise to 6 to 7. Transplant renal function was stable. Daily fasting glucose (mmol/l, mean +/- SD) was 5.6 +/- 1 and 5.3 +/- 0.6 during the first and second months respectively and post-Sustacal glucose was 5.7 +/- 0.8. Exogenous insulin therapy was progressively withdrawn and stopped during the ninth week. Thereafter, fasting glucose was 4.7 +/- 0.5, 24 h mean glucose was 6.6 +/- 0.5, and normoglycaemia was maintained after Sustacal. These data show that this mass of freshly isolated and cryopreserved islets from multiple donors provided sustained function (3 months) that reversed insulin-dependence in an immunosuppressed Type 1 diabetic patient treated with simultaneous islet-kidney transplantation.

Review of an Irish cervical smear service

Cervical cytology material from 5,815 women who presented to General Practitioners throughout Ireland for routine cervical smears were referred to our Pathology Laboratory. The smears were reviewed retrospectively in order to report on the incidence of dyskaryosis and other abnormalities diagnosed on cervical cytology. Evidence of dyskaryosis was found in a total of 2.2% and "borderline" changes in a total of 0.3% of smears. Cytology and subsequent histology were compared in cases of significant cervical intraepithelial neoplasia. Comparison in cases of moderate and severe dyskaryosis showed precise correlation between the diagnosis of cervical intraepithelial neoplasia on biopsy and its prediction on cytology in 30 of 33 cases. Over a third of women screened were in their 4th decade and the highest incidence of dyskaryosis was in this age group. Only 10% of those screened were 50 years or over and a third were aged 40 years and over. These facts are of relevance with regard to the problem of targeting the population at risk in the long term planning of routine cytology screening services in this country.

Predictive value of CA 125 for ovarian carcinoma in patients presenting with pelvic masses

Between November 1984 and May 1986, 56 patients presenting with a pelvic mass to the Gynecologic Oncology Service of McMaster University and the Hamilton Regional Oncology Center underwent laparotomy for possible ovarian cancer. All patients had blood drawn for CA 125 three days before operation. Levels above 35 U/mL were considered positive; CA 125 had a positive predictive value of 60%. False positives occurred in patients with nongynecologic malignancies and with benign gynecologic conditions. On the other hand, CA 125 had a negative predictive value of 100%, suggesting that this test may be useful in identifying those patients with pelvic masses at higher risk for malignancy, who may require transfer for surgery at a tertiary care center.

Prevalence of antibody to Chlamydia trachomatis in spontaneous abortion and infertility

A higher prevalence of Chlamydia trachomatis antibody occurred in 57.6% of women with recurrent abortion, but not in their male partners, compared to 33.7% of normal pregnant women (p less than 0.01) and 44.2% of infertile women (NS). The mean titer for the recurrent abortion group was not significantly elevated, compared to controls. Women with blocked fallopian tubes had the highest prevalence of elevated titers (p less than 0.01) and the highest mean titer (p less than 0.001). Despite multiple testing, no women or men were chlamydia culture-positive. The lack of isolation among patients with antibody could be due to cryptic infection at a site not amenable to culture or to inhibition by secretory IgA. There could also be nonspecific stimulation of chlamydial antibody caused by other infections such as mycoplasma. The presence, though at a low level, of antibody in culture-negative patients suggests chlamydia may not be directly associated with recurrent abortion but reflect previous exposure to chlamydia or an altered immune system.

The effects of changes in intracellular calcium on rat synaptosomal cyclic adenosine monophosphate

Cyclic adenosine monophosphate (cAMP) concentration was measured in rat striatal and hippocampal synaptosomes. Incubation in 50 mM K+ medium caused a decrease in both striatal and hippocampal cAMP: this effect was dependent on extracellular Ca2+. Replacement of NaCl with sucrose in the incubation medium increased cAMP. Incubation with 0.5 mM ouabain was without effect.

The effect of repeated mild stress on cerebral cortical adrenoceptors and noradrenaline synthesis in the rat

The effects of repeated mild stress on cortical alpha 2- and beta-adrenoceptor binding sites and on the rate of noradrenaline synthesis in cortical synaptosomes were measured. The stressful stimuli were either daily handling (1 min) or daily handling which included an i.p. saline injection. In both cases, rats killed 24 h after the last of 14 daily treatments showed an increase in noradrenaline synthesis rate and a decrease of alpha 2- and beta-adrenoceptor density. There were no changes in adrenoceptor density or the noradrenaline synthesis rate after either a single or 5 daily handlings plus saline injections. At no time was a change found in the Kd of either alpha 2- or beta-adrenoceptor binding sites. The results are discussed in relation to the effects on adrenoceptors of chronic antidepressant treatments.

Antidepressant activity of 5-aryl-2,3,5,6-tetrahydroimidazo[2,1-a]isoquinolin-5-ols

A series of 5-aryl-2,3,5,6-tetrahydroimidazo[2,1-a]isoquinolin-5-ols was prepared and evaluated for potential antidepressant activity in the reserpine-induced hypothermia model and selected central nervous system and autonomic activity tests. Several members of the series, notably the 4-chloro- and 4-fluorophenyl analogues, demonstrated pharmacological activity in the range of imipramine. Both compounds provided a marked potentiation of the 5-hydroxytryptophan-facilitated monosynaptic spike in the spinal cat preparation.

Serologic evidence of ureaplasma urealyticum infection in women with spontaneous pregnancy loss

Among 71 couples with histories of pregnancy wastage, 84.5% were colonized with Ureaplasma urealyticum and/or Mycoplasma hominis; whereas in couples with successful deliveries the incidence was 25.4%. The distribution of U. urealyticum and M. hominis was comparable in the fertile and infertile populations. Of women with positive cultures, 96% aborted, compared with an expected rate of 19% to 45%. Serologic studies revealed that, at delivery, 42.9% of infants of mothers with pregnancy losses had fourfold elevations in titers above the mothers' level compared with 15% of normal infants. Mothers with pregnancy wastage histories had elevated titers above their infants in 42.9% of cases compared with 10% of normal mothers. Thus, both mothers and fetuses had responded immunologically to the presence of U. urealyticum. When the mean antibody titers in the normal and pregnancy wastage groups were calculated for each ureaplasma serotype, the infants of mothers with pregnancy losses exhibited significantly elevated mean titers to serotypes 6 and 8, while the mothers had elevated mean titers to serotypes 4 and 8. These observations suggest that U. urealyticum causes infection in mothers and fetuses and that certain ureaplasma serotypes may be more pathogenic than others.

Efficacy of antibiotic therapy in preventing spontaneous pregnancy loss among couples colonized with genital mycoplasmas

Evidence suggests that genital mycoplasmas play a role in spontaneous abortion, prematurity, and perinatal morbidity and mortality rate. Since these organisms are sensitive to antibiotics, three treatment regimens were assessed for efficacy in preventing spontaneous pregnancy loss. The pregnancy loss rate was significantly reduced from 96% to 47.4% among those treated with doxycycline prior to conception and to less than 20% among those treated with erythromycin stearate only during pregnancy or with both regimens. The reduction in pregnancy loss rate was independent of maternal age, the number of previous abortions, gestational age at abortion, or other minor abnormalities. Diagnosis and treatment of mycoplasma infection following a first or later pregnancy loss equally prevented spontaneous loss in the next pregnancy. These observations suggest that appropriate treatment of mycoplasma infection could also prevent recurrent spontaneous abortion syndrome in couples with positive cultures.

Tapping ascites (2)

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Tapping ascites (1)

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Methylmalonic acidemia: 6 years' clinical experience with two variants unresponsive to vitamin B12 therapy

Two infants with lethargy, vomiting, convulsions, coma and marked metabolic acidosis were found to have very high concentrations of methylmalonic acid in their serum and urine. In vitro studies of fibroblasts demonstrated that the infants had different variants of methylmalonic acidemia.Vitamin B(12) was given in two different forms at 1 month of age and at 12 months of age. Each trial continued for 4 months but neither infant showed a clinical or biochemical response.In both infants hyperglycinemia, neutropenia and thrombocytopenia developed during acute metabolic crises only. Hypoglycemia was found in patient 2. Hyperammonemia was severe in patient 2 during acute crises but never appeared in patient 1. When clinically well, both infants continued to excrete abnormal amounts of methylmalonic acid in the urine and both had persistent compensated metabolic acidosis.Marked hyperuricemia developed in patient 1 at 18 months of age and led to progressive renal failure. Allopurinol therapy was necessary to keep the uric acid concentration within the normal range. Renal function returned to normal, as indicated by a marked increase in the renal clearance of creatinine and uric acid.Patient 1 is physically and mentally retarded, and has moderate hypotonia, hepatomegaly and persistent vomiting. Patient 2 has developed normally.The urine concentrations of methylmalonic acid in the four parents were normal.

The token economy: a living-learning environment

The use of a token-economy system to condition ward-wide behaviours in psychiatric in-patients, is gaining acceptance as a definite therapeutic modality (Franks, 1969).