Behavioral treatment of attentional dysfunction in chronic, treatment-refractory schizophrenia

Attentional impairment is both a core characteristic of schizophrenia and a factor in producing poor outcomes in rehabilitative treatment. While cognitive rehabilitation interventions have demonstrated some success, the severity of some patients' attentional impairment is such that they cannot attend to material in these treatments, leading to unsatisfactory outcomes. In this paper, we report on the results of a behavioral intervention designed to increase attention span in the lowest functioning group of schizophrenia patients on a long-term inpatient unit. The treatment is based on social-learning procedures, especially the principle of shaping. Results indicate that chronic, treatment refractory patients with severe attentional impairment, including those with IQs near or within the mentally retarded range, can improve their attention spans to over 45 minutes with this treatment.

Does low-dose, transdermal, norethisterone acetate reliably cause endometrial transformation in postmenopausal oestrogen-users?

In a prospective study, the symptomatic, psychological and endometrial effects of a combined oestradiol/progestogen transdermal therapeutic system which delivers a low daily dose of norethisterone acetate have been investigated in 18 postmenopausal women. Treatment was given in 28 day cycles. Patients received transdermal oestradiol 50 micrograms/day continuously and transdermal norethisterone acetate, 0.1-0.15 mg/day, was added for 14 days. Treatment was given for between 5 and 7 cycles. One patient discontinued therapy because of a skin reaction. Low dose, transdermal norethisterone acetate caused few adverse symptomatic or psychological side-effects and appeared well tolerated. Fourteen endometrial samples were obtained during the combined (norethisterone acetate/oestradiol) phase of the 5th, 6th or 7th treatment cycle. None showed hyperplastic or malignant change but proliferative endometrium, indicative of an inadequate progestational stimulus, was observed in 4 biopsy samples. Three of these patients had reported breakthrough bleeding during therapy. For these reasons, we regard this dose of transdermal norethisterone acetate as inadequate in combination with transdermal oestradiol 50 micrograms/day for routine use in postmenopausal oestrogen users.

Inhibition of estrogen biosynthesis and its consequences on gonadotrophin secretion in the male

Of the gonadal steroids in the male, testosterone is the most important regulator of gonadotrophin secretion. However, whether testosterone affects gonadotrophin secretion directly or whether it must first be aromatized to estrogens is controversial. We have reported extensively on the endocrine and anti-tumor effects of the non-steroidal aromatase inhibitors CGS 16949A and CGS 20267 in adult female rats. In these animals, both inhibitors potently and selectively inhibit estrogen biosynthesis. Thus these agents can be effectively used in studying estrogen-dependent processes. CGS 16949A was administered for 14 days to adult male rats, over a dose range which in females suppresses estradiol and elevates LH. In male rats a suppression of estradiol was seen, however, there was no significant effect on either serum LH or on the weights of androgen-dependent organs. CGS 16949A, when administered to healthy men at a dose of 1 mg b.i.d. for 10 days, causes a significant fall in plasma estradiol and significant elevations of plasma FSH and testosterone. Dose-dependent suppression of serum estradiol and an increase in serum testosterone and LH are seen after administration of single oral doses of CGS 20267. These results indicate that in the male rat, inhibition of aromatization of testosterone to estrogens does not influence gonadotrophin secretion whereas in men the negative feedback exerted by testosterone on gonadotrophin secretion is dependent on the aromatization of testosterone to estrogens.

A physiological mode of puberty induction in hypogonadal girls by low dose transdermal 17 beta-oestradiol

Transdermal 17 beta-oestradiol administration (17 beta-E2), used mainly in menopausal women, allows a continuous 17 beta-E2 delivery through the skin into the systemic circulation, avoiding intestinal and hepatic passage. In order to explore whether transdermal 17 beta-E2 could be used for the induction of puberty, 17 beta-E2 patches with low dose delivery were administered in nine prepubertal girls with Turner syndrome (bone age greater than 10.5 years) for a mean period of 2.2 years. Treatment schedule: 5 micrograms/day for 6-9 months, 10 micrograms/day for 6-9 months, 25 micrograms/day for long-term substitution; addition of cyclic gestagen p.o. after 18-24 months. Breast development started within 3 months of therapy and menstruation occurred after 2 years. Growth rate increased from 3.2 to 5.0 cm/year during the 1st year of therapy, height prediction did not change. Serum oestradiol (E2) and urinary E2 conjugates increased proportionally with 17 beta-E2 doses, serum oestrone (E1) rose much less. The possibility to imitate time course, clinical events and hormonal changes of normal puberty, the absence of adverse drug reactions and the excellent acceptance and easy mode of application suggest that transdermal 17 beta-E2 is optimally suited for hormonal substitution in girls with hypogonadism.

Transdermal administration of oestrogen/progestagen hormone replacement therapy

The effects of an oestrogen/progestagen transdermal therapeutic system (TTS) were evaluated in sixteen oestrogen-deficient women. The patients applied conventional oestradiol-TTS for 14 days, then two combined norethisterone acetate/oestradiol patches for a further 14 days. The treatment was repeated for five cycles. Ten patients then underwent metabolic studies. One patient had amenorrhoea, but the rest experienced regular withdrawal bleeding which was seldom heavy. Fourteen endometrial biopsy samples were taken during the fifth treatment cycle; none showed proliferative or hyperplastic features. The effects of transdermal norethisterone acetate on symptoms, lipid metabolism, and psychological status were determined by comparing features in the oestrogen-only phase and in the combined phase; the effects were very mild. These preliminary findings show that transdermal progestagen can be successfully administered in hormone replacement therapy to prevent endometrial proliferation while minimising the adverse effects that may be seen with oral administration.

An in vitro method to determine the selective inhibition of estrogen biosynthesis by aromatase inhibitors

Potency and selectivity of aromatase inhibition are parameters which ultimately influence the therapeutic efficacy of aromatase inhibitors. This report describes an in vitro model which allows an assessment of the selectivity with which aromatase inhibitors inhibit estrogen biosynthesis. Estrogen production was stimulated by incubating adult female hamster ovarian tissue with ovine LH. The production rates of estrogens (E), testosterone (T) and progesterone (P) were determined using radioimmunoassays to measure the amount of these steroids released into the incubation medium over a 4-hour incubation period. The selectivity of aromatase inhibition was assessed by determining the IC50S with which each inhibitor inhibited the production of E (end product), T (immediate precursor of E) and P (early precursor of E). Selectivity was studied for each of the 4 aromatase inhibitors, CGS 16949A (a new non-steroidal compound), 4-OH-androstenedione, aminoglutethimide and testolactone. CGS 16949A was the most potent of the four, followed by 4-OH-androstenedione, aminoglutethimide and testolactone. As far as selectivity was concerned, both CGS 16949A and 4-OH-androstenedione selectively inhibited aromatase judging from the IC50s for E and P production (CGS 16949A: IC50 for E & P = 0.03 & 160 microM, resp.; 4-OH-androstenedione: IC50 for E & P = 0.88 & greater than or equal to 330 microM, resp.). Aminoglutethimide was the least selective inhibitor of aromatase (IC50 for E & P = 13 & 60 microM, resp.). For testolactone, the least potent of the four (IC50 for E = 130 microM), no conclusive data were obtained concerning the selectivity of aromatase inhibition. Thus a simple, effective and reproducible method is described for assessing the selectivity with which aromatase inhibitors inhibit aromatase.

Three new epoxy-spirolactone derivatives: characterization in vivo and in vitro

The use of spironolactone, the most commonly used antimineralocorticoid compound, is limited by the occurrence of sexual endocrine effects. New antagonists are therefore required which lack these unwanted effects. Three 9 alpha,11 alpha-epoxy-derivatives of known aldosterone antagonists (spironolactone, prorenone and mexrenone) have been characterised in vitro and in vivo. In each experiment spironolactone was run as a reference. The introduction of the epoxy-group only marginally affected the binding affinity of these compounds for the mineralocorticoid receptor, whereas it caused a decrease for the androgen and progesterone receptors of between 10- and 500-fold. In vivo, all three epoxy-derivatives (3 mg/kg) were potent aldosterone antagonists, 1 to 2 times the potency of spironolactone in the rat. Parallel to the decreased affinity for the androgen and progesterone receptor in vitro, there was a 3- to 10-fold decrease of the antiandrogenic and progestagenic effect compared to spironolactone in the rat and in the rabbit, respectively. Virtually no disturbance of the vaginal or ovulatory cycle was observed with either epoxymexrenone or epoxyprorenone, although epoxyspironolactone caused a 20% decrease in ovulation. It appears therefore that the 9 alpha, 11 alpha-position of the steroid structure is a site of the molecule which can be modified to improve the specificity of aldosterone-antagonists not only in vitro, but also in vivo.

Antitumor efficacy in rats of CGP 19984, a thiazolidinedione derivative that inhibits luteinizing hormone secretion

The antitumor efficacy and the hormonal effects of the thiazolidine-dione derivative (sodium methyl((-3-methyl-2- ([5-methyl-3-(2-methylallyl)-4-oxo-2 thiazolidinyliden]hydrazono)-4-oxo-5-thiazolidinyl)) phosphate, CGP 19984, have been studied in in vivo rat prostatic and mammary cancer models. CGP 19984 significantly inhibited growth of the androgen-dependent Dunning R3327 rat prostate adenocarcinoma. Concomitant with tumor inhibition, a significant decrease in circulating luteinizing hormone and testosterone levels was observed, suggesting that the antitumor effects of drug treatment resulted primarily from inhibition of luteinizing hormone release and subsequently decreased testosterone synthesis. Drug treatment had little effect on serum prolactin or corticosterone levels. Animals showed no adverse effects from CGP 19984 except for a modest loss of body weight. In female rats, growth of the estrogen-independent MTW-9B rat mammary tumor was also inhibited by CGP 19984 and uterine weight and tumor progesterone receptor levels were reduced. The latter suggests that CGP 19984 treatment decreases circulating estrogen in female rats. However, the inhibitory effect of CGP 19984 on the growth of the MTW-9B tumor does not appear to be mediated by the action of the drug to lower estrogen levels, since this tumor is not dependent on estrogen for growth, and lower doses of CGP 19984 were found to be equally effective in reducing uterine weight, but had no antitumor activity. The ability of CGP 19984 to suppress gonadal function and to inhibit tumor growth suggests that this drug may have potential clinical application in the treatment of both hormone-dependent and -independent prostate and breast cancers.

Pharmacokinetics and pharmacodynamics of transdermal dosage forms of 17 beta-estradiol: comparison with conventional oral estrogens used for hormone replacement

This open-label, multiple-crossover study compared the pharmacokinetics and pharmacodynamics of transdermal 17 beta-estradiol and two oral forms of estrogen replacement therapy in postmenopausal women. The transdermal systems delivered either 0.025, 0.05, or 0.1 mg/day; oral dosages were 2 mg of micronized 17 beta-estradiol or 1.25 mg of conjugated equine estrogens. Transdermal estradiol provided serum and urinary levels of estradiol conjugates typical of the early follicular phase of the premenopausal woman and an estradiol/estrone ratio that approximated 1. The increments of both serum and urinary estradiol showed dose proportionality. Serum levels of estradiol obtained 24 hours after oral administration of estrogens were in a range similar to the steady-state levels obtained with transdermal estradiol delivery. Oral estrogens, however, induced an excessive rise in estrone to levels far beyond those observed in premenopausal women. Continuous application of transdermal estradiol over 3 weeks did not result in any accumulation of estradiol or estradiol conjugates. After only three doses of oral estrogens, there were signs of retention of estrogens. Suppression of gonadotropins by oral and transdermal administration of estrogens was in a similar range. This observation supports the conclusions that levels of circulating estradiol are relevant to efficacy, and that excessively high levels of estrone after oral administration of estrogens merely represents a nonphysiologic precursor or metabolite pattern.

17 beta-estradiol for postmenopausal estrogen replacement therapy

After physiological or surgical menopause, women are suddenly deficient in their main estrogenic hormone, 17 beta-estradiol. Only a very small amount of estradiol is still produced from adrenal precursors. More than 50 per cent of all postmenopausal women suffer for varying periods of time from the symptoms of this estrogen deficiency, most notably vasomotor instability (hot flashes) and sleep disturbances. The trophic symptoms of estrogen deficiency have longer lasting and cumulative consequences: accelerated loss of bone density that eventually increases the risk of fractures, genitourinary atrophy resulting in dyspareunia and urinary atrophy; and lipoprotein changes with increased risk of coronary heart morbidity and mortality. Today estrogen deficiency is mainly treated by oral estrogens--either conjugated equine estrogens or estradiol--in milligram doses far in excess of what would be required by the parenteral route. Taken orally, estradiol is largely transformed to estrone through metabolism in the liver. Certain undesirable side effects of estrogen therapy (e.g., increased renin substrate) are caused by the unphysiologic nature of the oral route of administration. Dosage forms for parenteral estrogen administration have been widely studied: vaginal or percutaneous creams, intranasal solutions, and sublingual tablets. All of these result in a pronounced, transient elevation of plasma concentrations of estradiol and a minor increase of estrone. An improved regimen, which produces more constant plasma concentrations, is achieved with an experimental estradiol implant or with a vaginal ring delivering estradiol. These studies demonstrate that daily estradiol doses of 0.2 mg and less are effective in reducing hot flashes. Effective doses of conjugated estrogens and estradiol administered by different routes achieve estradiol plasma concentrations of similar magnitude (between 35 and 100 pg/ml). Estrone plasma levels vary widely with these different regimens and do not seem to be directly related to efficacy. In summary, the literature indicates that efficacy of estrogen replacement for the treatment of the menopausal symptoms appears to relate to the magnitude of estradiol plasma levels; effective therapy is achieved by an estradiol regimen that maintains plasma estradiol levels of at least 35-55 pg/ml. Efficacy of estrogens in the prevention of osteoporosis as assessed by densitometry has been demonstrated for conjugated oral estrogens.(ABSTRACT TRUNCATED AT 400 WORDS)

Differences between in-vitro and in-vivo potencies of corticotrophins: an interpretation in terms of metabolic stability

Relative activities of a series of corticotrophin analogues have been measured by means of five different bioassays using the rat. Similarities in the relative potencies of various ACTH analogues determined using lipolysis or steroidogenesis in vivo and for the lipolytic and steroidogenic responses of fat pads and adrenal slices in vitro emerged and support the concept of a close structural relationship between the ACTH receptors in adipose and adrenal tissues in the rat. Potencies based on the steroidogenic response of isolated adrenal cells, adrenal slices or in-vivo experiments differed markedly from each other. Inactivation of peptides did not occur in the isolated cell assay, so it is likely that this assay estimates potency at the receptor level. A number of arguments suggest that the difference between the isolated cell assay and the other steroidogenic assays lies solely in the effects of peptide inactivation in the latter, and this allows the relative metabolic stabilities for the peptide analogues in these assays to be calculated. In this way it can be shown that: (1) Replacement of L-Ser by D-Ser in amino acid position 1 markedly increases the metabolic stability of the peptide and has only a slight effect on receptor properties. (2) Shortening at the NH2-terminus reduces the activity of peptides at the receptor level by several orders of magnitude, but increases their relative metabolic stability. (3) Introduction of amide groups at the CO2H-terminus markedly increases receptor potency of (1-16), (1-17) and (1-18) ACTH without affecting their metabolic stability in vivo. However, amidation of the CO2H-terminus does have a large effect on metabolic stability in the adrenal slice assay. (4) Replacement of Arg by Lys in positions 17 and 18 of (1-18) ACTH increases potency at the receptor level (adrenal cells) but has little effect on metabolic stability. The comparison of potencies obtained in the various assays, therefore, throws light on the significance of each assay. In addition, the effects of structural modification of analogues can be separately evaluated with respect to the metabolic stability of a peptide and its potency at the receptor level.