PubMed Health⌕ Search

Biomedical subjects

J Canick

Publications and source records attributed to J Canick.

11 recordsLinked to original sources

Molecular weight forms of inhibin A, inhibin B and pro-alphaC in maternal serum, amniotic fluid and placental extracts of normal and Down syndrome pregnancies.

BACKGROUND: Inhibin A, an established prenatal marker of Down syndrome (DS), exists in the maternal circulation in a number of isoforms. The present study explored whether specific inhibin A isoforms may be selectively increased in DS, offering the prospect of improved marker performance. METHODS: Second trimester maternal serum, placental extracts and amniotic fluid (AF) pools from both normal and DS pregnancies were fractionated by a combined immunoaffinity (IA) chromatography, preparative polyacrylamide gel electrophoresis (Prep-PAGE) and electroelution procedure. Inhibins A, B and pro-alphaC were determined in the eluted fractions by specific enzyme-linked immunosorbent assays (ELISAs) and the profiles of immunoactivity (IA) characterized in terms of molecular weight (MW) and percentage recovery. RESULTS: The MW patterns of inhibin A and pro-alphaC in maternal serum and AF were similar between DS and control pregnancies, both showing peaks between 25-40 k and approximately 65 k. AF contained, in addition, a higher proportion of <30 k inhibins A and B, and <25 k pro-alphaC forms. There were large differences in the inhibin forms present in DS placentae, with more 70 k and less 30-40 k inhibin A than in controls. CONCLUSIONS: The present data suggest that the processing, cleavage or secretion of inhibin MW forms by the DS placenta differs from normal. However, these differences are not reflected in maternal serum and so improvements in serum screening will not be afforded by measuring specific inhibin A isoforms.

Adult↗

Midpregnancy serum C-peptide concentration and subsequent pregnancy-induced hypertension.

OBJECTIVE: To test the hypothesis that elevated midpregnancy serum insulin (IRI) and C-peptide (CP) concentrations are associated with later development of pregnancy-induced hypertension (PIH), independent of prepregnancy obesity and midpregnancy blood pressure. RESEARCH DESIGN AND METHODS: In this prospective study, a cohort of normotensive women, ages > or = years performed a 50-g glucose challenge test at 24-30 weeks' gestational age. Blood samples were collected after an overnight fast and 1 h after glucose ingestion. Serum IRI and CP concentrations were measured in each sample. Maternal height, blood pressure and proteinuria were measured at the time of glucose challenge testing and after 36 weeks' gestational age. RESULTS: Of 320 subjects enrolled 44 women (13.8%) had subsequent PIH. Crude odds ratios (ORs) for devevelopment of PIH associated with each 1 U rise in log fasting IRI, log lasting CP. and glucosed-induced increase in CP (expressed as log [postprandial CP/fasting CP]) were 2.0 (95% CI 1.3-3.3), 1.8 (CI 1.2-2.7), and 2.3 (CI 1.1-4.9) respectively. After controlling for prepregnancy BMI, gestational age, and midpregnancy mean arterial pressure, adjusted ORs corresponding to log fastig IRI and CP for the development of PIH were 1.3 (95% CI 0.7-2.3) and 1.7 (CI 1.1-2.7) respectively, and, afterq adjustment for fasting CP, the adjusted OR of the glucose-induced rise in log CP was 3.7 (CI 1.5-9.3). CONCLUSIONS: Mid-pregnancy tasting and postoral glucose CP levels are associated with subsequent development of PIH, independent of maternal obesity and midpregnancy baseline blood pressure. These findings many reflect an amplified beta3-cell response to glycemic stimulus, similar to that found in states of insulin resistance, that appears to be independently associated with PIH.

Adult↗

Antiglucocorticoid treatment of depression: double-blind ketoconazole.

BACKGROUND: Hypercortisolemia is frequently observed in major depression but its pathophysiologic significance is unknown. In patients in whom hypercortisolism contributes to depressive symptomatology, antiglucocorticoid agents should have antidepressant effects. METHODS: Twenty medication-free depressed patients (eight of whom were hypercortisolemic and twelve of whom were not) received either the cortisol biosynthesis inhibitor, ketoconazole (400-800 mg/d p.o.) or placebo for 4 weeks in a double-blind manner, and behavioral ratings were performed weekly. RESULTS: Ketoconazole, compared to placebo, was associated with improvements in depression ratings in the hypercortisolemic, but not in the non-hypercortisolemic patients. The hormonal changes seen (decreased dehydroepiandrosterone and testosterone levels and increased pregnenolone and pregnenolone-sulfate levels) are consistent with enzymatic blockade of C17,20-lyase, 11-hydroxylase, and 17-hydroxylase. Ketoconazole was generally well tolerated with no occurrence of significant side effects or laboratory abnormalities. CONCLUSIONS: This small-scale double-blind study suggests that antiglucocorticoids have antidepressant activity in hypercortisolemic depressed patients. The data are consistent with a causal role of adrenocortical dysfunction in some depressed patients and suggest the need for larger-scale trials.

Adult↗

Glucocorticoid medication, memory and steroid psychosis in medical illness.

Steroid psychosis, including associated cognitive changes, is infrequent with short-term low-dose GC treatment, especially if only major objectively discernible effects are assessed. With long-term or high-dose treatment, however, or if milder subjectively discernible symptoms are also assessed, the incidence may be quite high. In lupus cerebritis, the differentiation between cognitive difficulties secondary to the underlying illness, which might warrant more aggressive GC treatment, versus those secondary to GC treatment itself, which might warrant dosage reduction, may be problematic, but certain guidelines have been proposed. Although GCs are widely prescribed and represent a clinically important class of medication, their deleterious effects may also be considerable. Glucocorticoids have prominent effects on central nervous system biochemistry and electrophysiology, and recent reports suggest they make certain hippocampal neurons more vulnerable to a variety of metabolic insults. Indeed, the clinical literature reviewed here is consistent with a disruption of hippocampus-dependent memory function (perhaps in conjunction with other areas of dysfunction), although in most cases the disruption is relatively mild and, in the vast majority, if not all cases, is reversible. From a clinical prospective, it is important to discuss potential neuropsychiatric side effects with patients before prescribing GC treatment. A greater understanding of the risk factors for experiencing SP and of its underlying mechanisms will lead to more informed clinical decision making and to a greater understanding of the role exogenous, and perhaps endogenous, GCs play in human cognition and behavior.

Adult↗

Dehydroepiandrosterone (DHEA) treatment of depression.

Dehydroepiandrosterone (DHEA) and its sulfate, DHEA-S, are plentiful adrenal steroid hormones that decrease with aging and may have significant neuropsychiatric effects. In this study, six middle-aged and elderly patients with major depression and low basal plasma DHEA f1p4or DHEA-S levels were openly administered DHEA (30-90 mg/d x 4 weeks) in doses sufficient to achieve circulating plasma levels observed in younger healthy individuals. Depression ratings, as well as aspects of memory performance significantly improved. One treatment-resistant patient received extended treatment with DHEA for 6 months: her depression ratings improved 48-72% and her semantic memory performance improved 63%. These measures returned to baseline after treatment ended. In both studies, improvements in depression ratings and memory performance were directly related to increases in plasma levels of DHEA and DHEA-S and to increases in their ratios with plasma cortisol levels. These preliminary data suggest DHEA may have antidepressant and promemory effects and should encourage double-blind trials in depressed patients.

Aged↗

Second trimester amniotic fluid oestriol, dehydroepiandrosterone sulphate, and human chorionic gonadotrophin levels in Down's syndrome.

OBJECTIVE: To investigate the reason for low maternal serum unconjugated oestriol (uE3) and raised human chorionic gonadotrophin (hCG) levels in Down's syndrome pregnancies. DESIGN: Measurement of uE3, total oestriol (tE3), dehydroepiandrosterone sulphate (DHEAS), a precursor of oestriol, and hCG in 15-20 week amniotic fluid samples from pregnancies with and without Down's syndrome. SETTING: The retrieval and use of stored amniotic fluid samples collected from women who had had an amniocentesis for antenatal diagnosis. SUBJECTS: 45 women with a Down's syndrome pregnancy and 224 unaffected controls of the same gestational age. RESULTS: The median level of amniotic fluid in affected pregnancies was low for uE3, tE3 and DHEAS but high for hCG: 0.50, 0.46, 0.35 and 1.58 multiples of the normal median, respectively. CONCLUSION: These results suggest that the abnormal maternal serum levels of uE3 and hCG in affected pregnancies are due mainly to abnormal feto-placental synthesis, rather than feto-maternal transfer.

Adult↗

The effects of the aromatase inhibitor delta 1-testolactone on gonadotropin release and steroid metabolism in polycystic ovarian disease.

This study was designed to examine the importance of aromatization in the gonadotropin secretory dynamics of polycystic ovarian disease (PCOD) by using the aromatase inhibitor delta 1 testolactone (TL) as a probe and to determine the effects of TL on steroid metabolism in vivo and in vitro. The pulsatile patterns of gonadotropin secretion and peripheral steroid levels were studied in eight women with PCOD before and during TL administration. There was a significant fall in peripheral estrone (E1) levels, a rise in peripheral androstenedione levels, and an increase in the androstenedione/E1 ratio during TL administration in these women. Isotopic determinations of androgen and estrogen production and metabolism before and during TL administration in two women confirmed a 90-95% decrease in the overall rate of aromatization. One patient also had an increase in the production and clearance rates of estradiol and E1 during TL administration, suggesting resistance to TL of the ovarian aromatase enzyme system. There were significant increases in both mean LH pulse amplitude [1.2 +/- 0.3 (SE) mIU/ml LER-907 before vs. 1.7 +/- 0.3 mIU/ml LER-907 during TL, P less than 0.05, paired t test] and frequency per 6 h (median: 3 before vs. 4 during TL, P less than 0.05, Wilcoxon signed rank test). Mean levels of LH and FSH did not, however, change significantly during TL administration. TL maximally inhibited neonatal rat hypothalamic aromatase in vitro at concentrations of 200 microM, a level theoretically obtainable during pharmacological therapy. These data suggest that: 1) in humans TL is a potent inhibitor of peripheral but not ovarian aromatase, and of hypothalamic aromatase in rats; 2) TL administration increases LH pulse amplitude and frequency in PCOD, either directly via hypothalamic aromatase inhibition, or indirectly by alterations in gonadal steroid metabolism; and 3) because of the multiple potential actions of TL, its usefulness as a probe in studies of gonadotropin secretion in PCOD is limited.

Adult↗

Placental sulfatase deficiency: a case study.

A pregnancy with placental sulfatase deficiency was suspected when a 36-year-old patient at 41 weeks of gestation was found to have extremely low urinary estriol excretion and an otherwise normal prenatal course. The maternal plasma levels of estriol and estradiol 17-beta (E2) were extremely low and estetrol (E4) was undetectable (less than 40 pg/ml), whereas dehydroepiandrosterone sulfate (DS) was normal. THE AMNIOTIC Fluid DS concentration was 22-fold higher than the mean of normal pregnancy, while that of dehydroepiandrosterone (D) and androstenedione (A) was normal. Following intravenous infusion of 50 mg DS, no rise of plasma E2 was noted and plasma E4 levels remained undetectable. At 42 weeks of pregnancy, after induction of labor failed, a healthy male infant was delivered by cesarean section. The umbilical vein (UV) and umbilical artery (UA) levels of DS were extremely high, and those of E2 and E4 were subnormal. The UA level of A was normal and the levels of D and testosterone were slightly elevated. In vitro studies of placental microsomes and the 10,000 x g supernantant confirmed the diagnosis of placental sulfatase deficiency. The infant at 6 months of age had normal growth and development and normal peripheral plasma DS concentration.

Adult↗