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R Castello

Publications and source records attributed to R Castello.

At least 19 recordsLinked to original sources
PubMed2000

Antiandrogen drugs lower serum prostate-specific antigen (PSA) levels in hirsute subjects: evidence that serum PSA is a marker of androgen action in women.

Assay by ultrasensitive methods of serum prostate-specific antigen (PSA) recently demonstrated that many women have detectable levels of this molecule. Interestingly, serum PSA concentrations were higher in hirsute than in nonhirsute subjects, suggesting that, also in females, PSA may be regulated by androgens. To establish the potential for this assay as a biochemical marker of androgen action in women, we studied 40 hirsute subjects recruited in a double-blind, placebo-controlled, 6-month trial assessing the effects of 3 different antiandrogen drugs: spironolactone, flutamide, or finasteride. In each subject, serum PSA, free testosterone, and 3alpha-androstanediol glucuronide were determined at baseline and at the end of treatments. At baseline, PSA concentrations were higher in these 40 women than in 19 nonhirsute healthy controls (12.9+/-1.5 vs. 4.9+/-0.7 pg/mL, P = 0.03) and significantly correlated with serum free testosterone (r = 0.37, P<0.005). After treatments, the 29 hirsute subjects given active drugs showed significant reduction of serum PSA levels (7.2+/-1.4 vs. 14.7+/-3.0 pg/mL, P = 0.002). This phenomenon was correlated to baseline PSA values. No change was found in the placebo group. In conclusion, serum PSA is increased in many hirsute women. A 6-month course of antiandrogen treatments with spironolactone, flutamide, or finasteride determines a reduction of PSA levels in these subjects. These results suggest that serum PSA is a biochemical marker of androgen action in tissues of female subjects.

Adult↗
PubMed2000

Comparison of spironolactone, flutamide, and finasteride efficacy in the treatment of hirsutism: a randomized, double blind, placebo-controlled trial.

To compare objectively the efficacies of spironolactone (100 mg/day), flutamide (250 mg/day), and finasteride (5 mg/day) in the treatment of hirsutism, 40 hirsute women were randomly assigned to double blind treatments with 1 of these 3 drugs or placebo for 6 months. Before and at the end of treatment, hirsutism was quantitatively measured in each subject by determination, by computer-assisted light microscopy, of the largest diameter of 5 hairs plucked from the linea alba. These measurements were averaged to produce a mean hair shaft diameter. For each subject, baseline and posttreatment assessments were carried out at the same time by an investigator blinded to both time and type of therapy. In addition, a semi-quantitative clinical evaluation was carried out by a modification of the Ferriman-Gallwey (F-G) scoring method, performed by a single investigator. At baseline the 4 groups of women had similar hair diameters and F-G scores. After 6 months of therapy all groups of subjects given active drugs showed reductions of their hair diameters, without statistically significant differences among groups (mean change +/- SEM, -11.7+/-5.6%, -18.0+/-6.1%, and -12.6+/-6.7%, respectively, in the spironolactone, flutamide, and finasteride groups). F-G scores were also significantly reduced in women receiving antiandrogen drugs, again without differences among groups (mean change, -41.0+/-5.5%, -38.9+/-7.2%, and -31.6+/-3.7%, respectively). No significant changes from baseline values were recorded by either hair diameter (-1.4+/-5.2%) or F-G score (+5.4+/-3.7%) assessment in the placebo group. In conclusion, spironolactone, flutamide, and finasteride are all effective in the treatment of hirsutism. After a 6-month course of therapy, the clinical efficacies of these drugs, at least at the doses used, are similar.

Adult↗
PubMed2000

Metformin effects on clinical features, endocrine and metabolic profiles, and insulin sensitivity in polycystic ovary syndrome: a randomized, double-blind, placebo-controlled 6-month trial, followed by open, long-term clinical evaluation.

In the last few years some studies assessed the effects of attenuation of hyperinsulinemia and insulin resistance, obtained by insulin sensitizing agents, in women with polycystic ovary syndrome (PCOS), suggesting potential scope for these drugs in treating the whole spectrum of reproductive, endocrine, and metabolic abnormalities found in such subjects. However, the results of these studies, mostly uncontrolled and short-term, are still inconclusive, and there is no long-term follow-up. In the present study, 23 PCOS subjects [mean (+/- SE) body mass index 30.0+/-1.1 kg/m2] were randomly assigned to double-blind treatment with metformin (500 mg tid) or placebo for 6 months, while maintaining their usual eating habits. Before and after treatment, menstrual history, endocrine and metabolic profiles, serum 17-hydroxyprogesterone response to GnRH-agonist testing, and insulin sensitivity measured by the glucose clamp technique were assessed. Eighteen of these women, as well as 14 additional PCOS patients, were subsequently given metformin in an open trial for 11.0+/-1.3 months (range 4-26), to assess long-term effects of treatment and baseline predictors of metformin efficacy on reproductive abnormalities. After metformin treatment, mean frequency of menstruation improved (P = 0.002), due to striking amelioration of menstrual abnormalities in about 50% of subjects. Women given metformin showed reduced plasma insulin (at fasting: P = 0.057; during the clamp studies: P<0.01) and increased insulin sensitivity (P<0.05). Concurrently, ovarian hyperandrogenism was attenuated, as indicated by significant reductions in serum free testosterone (P<0.05) and in the 17-hydroxyprogesterone response to GnRH-agonist testing (P<0.05). No changes were found in the placebo group. Only comparable minor changes in body mass index were found both in the metformin group and in the placebo group. In the open, long-term trial 17 women (54.8%) showed striking improvements of their menstrual abnormalities and were considered as responders. Logistic regression analysis of baseline characteristics in responders and nonresponders showed that plasma insulin, serum androstenedione, and menstrual history were independent predictors of the treatment's clinical efficacy. In 10 subjects whose menses proved regular after treatment, the great majority of cycles became ovulatory (32 out of 39 assessed, 79%). In conclusion, in women with PCOS metformin treatment reduced hyperinsulinemia and hyperandrogenemia, independently of changes in body weight. In a large number of subjects these changes were associated with striking, sustained improvements in menstrual abnormalities and resumption of ovulation. Higher plasma insulin, lower serum androstenedione, and less severe menstrual abnormalities are baseline predictors of clinical response to metformin.

17-alpha-Hydroxyprogesterone↗
PubMed2000

Power spectral analysis of heart rate in hypothyroidism.

OBJECTIVE: The aim of the present study was to evaluate the impact of hypothyroidism on the autonomic regulation of the cardiovascular system by analysing separately sympathetic and parasympathetic influences on the heart. DESIGN: In seven newly diagnosed untreated hypothyroid patients we analysed power spectral density of heart rate cyclic variations at rest, while lying, and while standing. The same protocol was repeated after the induction of stable euthyroidism by levothyroxine (L-T(4)) treatment. The results were also compared with those obtained from seven age-, sex- and body mass index-matched control subjects. METHODS: Heart rate variability was evaluated by autoregressive power spectral analysis (PSA). This method allows reliable quantification of low frequency (LF) and high frequency (HF) components of the heart rate power spectral density. These are considered to be under mainly sympathetic and purely parasympathetic control respectively. In addition, heart rate variations during deep breathing, lying to standing, and Valsalva's manoeuvre were assessed. RESULTS: PSA showed a sharp reduction in the HF (parasympathetic) component in hypothyroid subjects compared with controls (lying, 29.4+/-5.4 vs 47.7+/-6.3 normalized units (NU) (means +/- s.e.m.), P<0.05; standing, 14.0+/-3.5 vs 32.1+/-3.6NU, P<0.005). Conversely, the LF (mainly sympathetic) component was higher in hypothyroid subjects than in controls (lying, 61.6+/-6.4 vs 45.4+/-6.7 NU; standing, 71.7+/-8.0 vs 53.1+/-5.6NU), this difference being significant in the standing position. Hence, the LF/HF ratio, which is considered an index of sympathovagal balance, was increased in hypothyroid subjects while both lying (2.75+/-0.6 vs 1.16+/-0.3; P<0.05) and standing (10.0+/-3.7 vs 1.85+/-0.3; P<0. 02). Total heart rate variability, expressed as total power spectral density, was lower in hypothyroid patients than in control subjects, this difference being significant in the lying position (574+/-126 vs 2302+/-994ms(2), P<0.05). In patients re-examined after L-T(4) therapy, complete normalization of cardiovascular parameters was observed (LF/HF ratio, lying, 1.26+/-0.4; standing, 2.56+/-0.8, both P<0.01 vs baseline values). The response to conventional cardiovascular autonomic tests was not significantly different between hypothyroid patients and healthy controls, and did not change in patients after therapy. CONCLUSIONS: These results suggest that, contrary to the clinical picture, thyroid hormone deficiency is associated with an increased sympathetic influence on the autonomic cardiovascular system. The changes in sympathetic function could be explained by a secondary adaptation to an altered cardiovascular responsiveness.

Electrocardiography↗
PubMed1999

Developmental expression of the peripheral-type benzodiazepine receptor and the advent of steroidogenesis in rat adrenal glands.

Although the precise mechanism whereby cholesterol is transported across the outer mitochondrial membrane is uncertain, a multimeric receptor complex termed the peripheral-type benzodiazepine receptor (PBR) appears essential for this process. We therefore predicted that adrenal cells at different developmental stages would express PBR coincidentally with the advent of steroidogenesis. Adrenals of neonatal rats demonstrate greatly reduced sensitivity to ACTH that gradually increases after the first 2 weeks of life. Thus, neonates have lower circulating corticosterone levels following exposure to stress. We examined mitochondrial PBR ligand binding activity, immunoreactive (ir) PBR content, and adrenal sensitivity to ACTH in vivo and in vitro. Ontogeny of both mitochondrial PBR ligand binding capacity and irPBR directly paralleled that of ACTH-inducible steroidogenesis in isolated rat adrenal cells and in rats injected with ACTH. In addition, neonatal PBR had approximately 2-fold higher affinity for PK11195, a synthetic ligand that binds with high affinity to PBR. No correlation was observed during neonatal life between ir-steroidogenic acute regulatory (StAR) protein content and steroidogenesis. These results are consistent with the hypothesis that PBR is an absolute prerequisite for adrenocortical steroidogenesis, and suggest that the stress hyporesponsive period of neonatal rats may result from decreased PBR expression. In addition, the higher affinity of neonatal PBR and the relatively high basal expression of StAR protein in neonatal adrenals may partly explain the high constitutive steroidogenesis characteristic of neonatal rat adrenal cells.

Adrenal Glands↗
PubMed1999

Spironolactone, but not flutamide, administration prevents bone loss in hyperandrogenic women treated with gonadotropin-releasing hormone agonist.

GnRH agonists (GnRHa) have recently been proposed for the treatment of hirsutism in women with the polycystic ovary syndrome (PCOS). As most of these subjects have increased androgen secretion from both ovaries and adrenal glands, the association of GnRHa with antiandrogen drugs might enhance the clinical response to treatment. On the other hand, this association might also potentiate the adverse effects of GnRHa on bone metabolism, generating a potentially harmful situation at the skeletal level. In this study we investigated in 41 PCOS patients the skeletal effects of a 6-month course of GnRHa (tryptorelin, 3.75 mg, i.m., monthly), either alone (n = 12) or associated with the antiandrogen drugs spironolactone (100 mg, orally, once daily; n = 14) or flutamide (250 mg, once daily; n = 15). In all subjects bone mineral density was measured before and after treatment by dual energy x-ray absorptiometry at the lumbar spine (L2-L4) and at the femoral neck and Ward's triangle. In addition, at baseline and after 6 months of therapy, bone metabolism markers (serum and urinary calcium, serum phosphorus and alkaline phosphatase, plasma osteocalcin, and urinary hydroxyproline) and endocrine parameters (serum gonadotropins, estradiol, and free testosterone) were assayed. Women given either GnRHa alone or associated with spironolactone or flutamide were similar for age and body mass index. At baseline, the 3 groups of PCOS women were also similar for endocrine and bone parameters. After 6 months, all treatments determined similar striking suppressions of serum gonadotropins and sex steroids. Concurrently, bone mineral density was significantly reduced at all examined sites in subjects receiving either GnRHa alone or GnRHa plus flutamide. Conversely, women given GnRHa plus spironolactone did not show any change in skeletal mass from baseline values (P < 0.05-0.01 among groups). Biochemical parameters of bone metabolism were consistent with densitometric assessments. In conclusion, after a 6-month course of therapy, bone mineral density is reduced in PCOS women given either GnRHa alone or GnRHa plus flutamide, but not in those receiving GnRHa plus spironolactone. The mechanisms of the bone-sparing effect of spironolactone remain to be determined. Nevertheless, this drug could represent a useful tool to prevent skeletal loss in women given GnRHa as well as in other hypoestrogenic conditions, in particular when estrogens are not recommended.

Adult↗
PubMed1998

Effect of treatment of isolated systolic hypertension on left ventricular mass.

CONTEXT: Left ventricular (LV) hypertrophy is a common problem among elderly patients with isolated systolic hypertension (ISH), but the effect of treatment of ISH on LV mass is not known. OBJECTIVE: To assess the ability of antihypertensive drug treatment to reduce LV mass in ISH. DESIGN: Echocardiographic Substudy of the Systolic Hypertension in the Elderly Program (SHEP). PATIENTS: A total of 104 participants at the St Louis SHEP site who had interpretable baseline echocardiograms, 94 of whom had 3-year follow-up echocardiograms. INTERVENTION: The SHEP participants were randomized to placebo or active treatment with chlorthalidone (12.5-25 mg/d), with atenolol (25-50 mg/d) added if necessary to maintain goal blood pressure. MAIN OUTCOME MEASURE: Change in LV mass assessed by echocardiography. RESULTS: Minimum follow-up was 3 years. In the active treatment group, 91% and 80% of subjects were receiving treatment with chlorthalidone alone by the end of years 1 and 3, respectively. The LV mass index was 93 g/m2 in the active treatment group and 100 g/m2 in the placebo group (P<.001). The LV mass index declined by 13% (95% confidence interval, - 3% to - 23%) in the active treatment group compared with a 6% increase (95% confidence interval, - 3% to + 16%) in the placebo group over 3 years (P=.01). CONCLUSION: Treatment of ISH with a diuretic-based regimen reduces LV mass.

Aged↗
PubMed1998

Prognostic significance of late-peaking left ventricular velocity contour in patients with aortic stenosis undergoing valve replacement.

BACKGROUND: The presence of an abnormal late-peaking left ventricular velocity contour, detected by Doppler echocardiography, has been reported in patients with hypertrophic cardiomyopathy, left ventricular hypertrophy, and aortic stenosis. METHODS AND RESULTS: To evaluate the clinical and prognostic significance of this characteristic Doppler finding, we studied a group of patients (n = 57) with isolated AS undergoing aortic valve replacement. Patients were divided into two groups according to the presence (n = 28) or absence (n = 29) of a hypertrophic late-peaking left ventricular velocity pattern. There were no differences between the groups with respect to age, sex, and presence of coronary artery disease. Peak preoperative aortic valve gradients were similar in both groups (70 vs. 67 mm Hg; p = not significant). The postoperative course of patients with abnormal late-peaking ventricular velocity contour was complicated by a higher incidence of arrhythmias (80% vs. 38%; p = 0.0002). Hypotension and the use of inotropic support were significantly more common in the group with abnormal late-peaking ventricular velocity contour (79% vs. 24%; p = 0.0001 and 76% vs. 26%; p = 0.0001, respectively). Hemodynamically, patients with a late-peaking velocity pattern exhibited a higher pulmonary diastolic pressure (16+/-3 vs 12+/-2 mm Hg; p = 0.0003), wedge pressure (12+/-4 vs 10+/-2; p < 0.05), and systemic vascular resistance (2126+/-459 vs 1553+/-199; p = 0.0001) and lower cardiac index (2.4+/-0.3 vs 2.9+/-0.4; p = 0.0001). CONCLUSIONS: An abnormal late-peaking ventricular velocity contour pattern appears to be a high risk marker for postoperative complications in patients undergoing aortic valve replacement. Routine Doppler evaluation in patients undergoing valve replacement for AS may therefore identify these patients.

Adult↗
PubMed1998

Mobile aortic atheroma and systemic emboli: efficacy of anticoagulation and influence of plaque morphology on recurrent stroke.

OBJECTIVES: We sought to determine the influence of plaque morphology and warfarin anticoagulation on the risk of recurrent emboli in patients with mobile aortic atheroma. BACKGROUND: An epidemiologic link between aortic atheroma and systemic emboli has been described both in pathologic and transesophageal studies. Likewise, a few studies have found an increased incidence of recurrent emboli in these patients. The therapeutic implications of these findings has not been studied. METHODS: Thirty-one patients presenting with a systemic embolic event and found to have mobile aortic atheroma were studied. The height, width and area of both immobile and mobile portions of atheroma were quantitated. The dimensions of the mobile component was used to define three groups: small, intermediate and large mobile atheroma. The patients were followed up by means of telephone interview and clinical records, with emphasis on anticoagulant use and recurrent embolic or vascular events. RESULTS: Patients not receiving warfarin had a higher incidence of vascular events (45% vs. 5%, p = 0.006). Stroke occurred in 27% of these patients and in none of those treated with warfarin. The annual incidence of stroke in patients not taking warfarin was 0.32. Myocardial infarction occurred in 18% of patients also in this group. Taken together, the risk of myocardial infarction or stroke was significantly increased in this group (p = 0.001). Forty-seven percent of patients with small, mobile atheroma did not receive warfarin. Recurrent stroke occurred in 38% of these patients, representing an annual incidence of 0.61. There were no strokes in patients with small, mobile atheroma treated with warfarin (p = 0.04). Likewise, none of the patients with intermediate or large mobile atheroma had a stroke during follow-up. Only three of these patients had not been taking warfarin. CONCLUSIONS: Patients presenting with systemic emboli and found to have mobile aortic atheroma on transesophageal echocardiography have a high incidence of recurrent vascular events. Warfarin is efficacious in preventing stroke in this population. The dimension of the mobile component of atheroma should not be used to determine the need for anticoagulation.

Aged↗
PubMed1998

Effect of hyperandrogenism and menstrual cycle abnormalities on bone mass and bone turnover in young women.

OBJECTIVE: Prolonged period of amenorrhoea are regarded as a risk factor for the appearance of osteoporosis. Amenorrhoea is a feature of different pathological conditions with heterogeneous endocrine profiles. We evaluated bone mineral metabolism in patients with polycystic ovary syndrome (PCOS), hypothalamic amenorrhoea and idiopathic hirsutism in order to establish the relative importance for the maintenance of normal bone mass of ovulatory cycles and androgen and oestrogen production. PATIENTS AND MEASUREMENTS: Bone mineral density (BMD), bone turnover markers and endocrine profile were evaluated in 51 patients with PCOS, 24 patients with idiopathic hirsutism, 26 patients with hypothalamic amenorrhoea and 35 healthy women. Body mass index (BMI) ranged between 20.1 and 31.0 kg/m2, and age from 17 to 33 years. Thirty-eight of the PCOS patients were amenorrhoeic (< 4 menstrual cycles/year). RESULTS: Spine and femoral BMD were significantly decreased and bone markers (serum osteocalcin, and urinary excretion of free deoxypyridinoline, cross-linked N-telopeptide and hydroxyproline) significantly increased in the patients with hypothalamic amenorrhoea, when compared to control subjects and the other two patient groups. In the sub-group of PCOS patients with amenorrhoea, spine and femoral neck BMD was significantly lower than in patients with idiopathic hirsutism and the non-amenorrhoeic PCOS patients. In all PCOS patients, spine and neck BMD were positively correlated (P < 0.05) with serum androstenedione and free testosterone levels. CONCLUSIONS: The results of this study suggest that in patients with polycystic ovary syndrome the deleterious effect on bone of amenorrhoea is balanced by androgen overproduction.

Adolescent↗
PubMed1998

Differential sensitivity to ACTH, but not stress, in two sources of outbred Sprague-Dawley rats.

Adrenocorticotropic hormone (ACTH) is the major regulator of adrenocortical steroidogenesis in mammals. By comparing the sensitivity to ACTH of isolated adrenocortical cells from two sources of the same strain (Sprague-Dawley, SD) of outbred rats, we have identified a source of rat with low sensitivity to ACTH in vitro. Cells isolated from Holtzman SD rats had a high sensitivity to ACTH (minimal effective concentration 50 pg/ml), whereas Taconic SD rats had a low sensitivity (minimal effective concentration 250 pg/ml; maximal steroidogenesis < 50% of Holtzman cells). The responsiveness to analogues of cyclic adenosine monophosphate and cholesterol was also significantly lower in Taconic SD rats. Taconic adrenals were smaller, had significantly more mitochondria per cell, but approximately 20% less total lipid droplet volume per cell. There was no difference in latency to ACTH in vitro; however, steroidogenesis plateaued in Taconic cells after 25 min, while Holtzman cells secreted corticosterone almost linearly for at least 120 min. By contrast, the cyclic adenosine monophosphate secretion increased at the same rate for at least 120 min in cells from both sources. There were no differences between cells from the two sources in immunoreactive steroidogenic enzyme content. In vivo, the magnitude of the ACTH and corticosterone responses to two types of stress were similar in both sources. The thymus glands of Holtzman rats were significantly larger than those of Taconic rats. It is concluded that: (1) reduced sensitivity to ACTH in vitro in Taconic SD rats results from differences in the later stages of the steroidogenic pathway; (2) factors in addition to ACTH are required for maximal steroidogenesis in Taconic SD rats: (3) a comparison of the steroidogenic pathways in adrenal cells from these two sources of outbred rats should be useful in further delineating the relative importance of putative intracellular signalling mechanisms involved in initiation and maintenance of steroidogenesis, and (4) these data suggest that different sources of the same strain of rats sufficiently diverge over time to become separate strains ('substrains'). Overreliance on a single source of laboratory rodent may obscure natural variability in endocrine responses to stress and provide a misleading indication of homogeneity of responses.

Adrenal Cortex↗
PubMed1997

Intermittent Etidronate partially prevents bone loss in hirsute hyperandrogenic women treated with GnRH agonist.

Treatment with gonadotropin-releasing hormone (GnRH) agonist leads to enhanced bone turnover and accelerated bone loss in premenopausal women with endometriosis, uterine leiomyomatomas and hirsutism. Sodium etidronate is a powerful inhibitor of bone resorption which had been proven efficacious in the prevention and treatment of postmenopausal osteoporosis. The objective of this study was to evaluate the skeletal effects of 6 months of therapy with the depot preparation of the GnRH agonist triptorelin (decapeptil 3.75 mg intramuscularly every 4 weeks) in 24 hirsute patients, aged 24-33 years, with hyperandrogenic chronic anovulation. Ten patients also received cyclical etidronate in an oral dose of 400 mg/day for 2 weeks, followed by an 11-week period of 500 mg/day elemental oral calcium (one cycle). The remaining 14 patients received 500 mg/day of elemental calcium continuously. After 6 months all treatments were discontinued for at least a further 6 months. Bone mineral density (BMD) at lumbar spine and hip (dual-energy X-ray absorptiometry, Sophos LXRA, France) and biochemical markers (serum alkaline phosphatase, osteocalcin, urinary N-telopeptide and hydroxyproline/creatinine ratio) were evaluated at baseline, 6 months and 12 months. In the group given GnRH agonist alone BMD fell significantly at all measured skeletal sites during the first 6 months. In the patients treated with etidronate a significant decrease in BMD was observed at lumbar spine but not in the femoral neck and trochanter, and the changes at lumbar spine and trochanter were significantly smaller than those in the control group. At 6 months bone turnover was also increased in patients treated with GnRH and calcium. Cyclical etidronate prevented the increase in biochemical markers of bone formation and resorption, with the exception of calcium/creatinine excretion, which was significantly increased in both groups. Six months after treatment withdrawal BMD did not recover in either group. Biochemical markers (N-telopeptide, serum alkaline phosphatase) remained increased in those patients previously treated with calcium alone while they remained close to baseline values in the patients treated with cyclical etidronate. Our study indicates that: (1) GnRH agonist therapy causes remarkable bone loss in young individuals with androgen excess who are expected to have increased bone mass; (2) this bone loss can be partially prevented by intermittent cyclical etidronate therapy.

Adult↗
PubMed1997

Pharmacologic stress-induced regional myocardial blood flow heterogeneity and left ventricular wall thickening abnormality: comparison of intravenous adenosine with dipyridamole in a model of critical coronary stenosis.

Variations in reported sensitivity of myocardial perfusion scans or wall motion abnormalities during pharmacologic stress with intravenous adenosine and dipyridamole may be caused by differences in myocardial oxygen demand or myocardial blood flow redistribution induced by each agent. To investigate the physiologic correlates of functional abnormalities during pharmacologic stress testing, regional myocardial blood flow (radiolabeled microsphere technique) and left ventricular segmental wall thickening (quantitative two-dimensional echocardiography) were measured in 9 dogs with an open chest model of critical stenosis of the left circumflex coronary artery. Data were obtained at baseline and peak drug infusion for intravenous adenosine (0.42 mg/kg over a 3-minute period) and for intravenous dipyridamole (0.56 mg/kg over a 4-minute period). Adenosine and dipyridamole induced regional flow abnormality in 7 (77%) of 9 dogs. Myocardial segments with decreased endocardial/epicardial flow ratio were similar for both agents (2.9 +/- 1.8 vs 2.7 +/- 1.3, p = [NS]). Segments with myocardial flow heterogeneity (ratio of endocardial flow to control left anterior descending/left circumflex endocardial flow) were similar for both agents (2.7 +/- 0.9 vs 2.3 +/- 1.0, p = NS). Adenosine-induced wall thickening abnormality (77% vs 55% with dipyridamole) correlated with regional flow abnormality. Significantly lower mean arterial pressure (53 +/- 1.7 mm Hg vs 64 +/- 1.9 mm Hg, p < 0.01) and more prolonged drug effect (18 +/- 6.4 min vs 3 +/- 1.4 min, p < 0.001) were seen for dipyridamole compared with adenosine. Adenosine induces regional flow abnormality similar to dipyridamole but with less hemodynamic perturbation, and adenosine-induced wall thickening abnormality more closely parallels regional flow abnormality.

Adenosine↗
PubMed1997

Allelic loss in parathyroid tumors from individuals homozygous for multiple endocrine neoplasia type 1.

Homozygosity for the multiple endocrine neoplasia type 1 (MEN1) gene mutation was described in two of three affected siblings of a kindred in which both parents and the third daughter were heterozygotes. Surprisingly, in the two homozygotes, the disease history did not differ from the one of the heterozygotes. In the attempt to unravel genetic differences in parathyroid tumorigenesis between homozygotes and heterozygotes, restriction fragment length polymorphism analysis and microsatellite PCR analysis for loss of heterozygosity (LOH) at the MEN1 gene region on chromosome 11q13 was performed in parathyroid tissues removed at surgery from the mother, her heterozygous sister, and the three siblings. Allelic losses were evidenced in the larger glands of each patient, with a similar pattern of chromosome 11q12-13 losses. The somatic mutation consisted of a large lose of genetic material from chromosome 11. No gross differences exist in the 11q12-13 LOH observed between homozygous and heterozygous carriers. Interestingly, one of the parathyroid tumors from one heterozygote exhibited region of skipped LOH at the 11q12-13 region. The region in the depth of the critical interval retained heterozygosity, whereas those flanking it shared LOH. These findings indicate that inactivation of both copies of the MEN1 gene are not sufficient for parathyroid tumor development in MEN 1 patients and that tumor suppressor genes, other than the MEN1 gene on chromosome 11 or on other chromosomes, can be involved in the pathogenesis of parathyroid tumorigenesis in MEN 1 syndrome.

Chromosome Deletion↗
PubMed1996

Outcome of long-term treatment with the 5 alpha-reductase inhibitor finasteride in idiopathic hirsutism: clinical and hormonal effects during a 1-year course of therapy and 1-year follow-up.

OBJECTIVE: To evaluate the long-term efficacy of the 5 alpha-reductase inhibitor finasteride in idiopathic hirsutism. DESIGN: Prospective clinical study. SETTING: Outpatients in a university hospital. PATIENT(S): Fourteen young women with idiopathic hirsutism. INTERVENTION(S): Finasteride, 5 mg once daily, was given for 12 months. MAIN OUTCOME MEASURE(S): Degree of hirsutism, graded by a modified Ferriman and Gallwey score, serum sex hormones, and serum and urinary markers of 5 alpha-reductase activity. Clinical outcome was evaluated up to and including the 1-year post-treatment period. RESULT(S): The Ferriman and Gallwey score showed a remarkable reduction after 12 months of finasteride treatment (4.4 +/- 0.7 versus 11.8 +/- 1.0; mean +/- SEM). Serum levels of the two 5 alpha-reductase activity markers, dihydrotestosterone and 3 alpha-androstanediol glucuronide, decreased, and urinary C19 and C21 5 beta:5 alpha steroid metabolite ratios consistently increased during finasteride administration. These changes were reversed readily after cessation of treatment. No significant adverse effect was reported. Nine of 14 women completed the 1-year post-treatment follow-up. Their hirsutism scores were increased substantially as compared with values recorded at the end of therapy, but still were lower than baseline values. CONCLUSION(S): The 5 alpha-reductase inhibitor finasteride is effective and well tolerated in longterm treatment of women with idiopathic hirsutism. Post-treatment follow-up suggests that drug effects on hair growth are sustained in the majority of subjects with this disorder.

5-alpha Reductase Inhibitors↗