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Effects of the Strong Hearts program after a major cardiovascular event in patients with cardiovascular disease. J Osteopath Med 2023; 123:279-285. [PMID: 36958944 DOI: 10.1515/jom-2022-0141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Accepted: 02/21/2023] [Indexed: 03/25/2023]
Abstract
CONTEXT Cardiac rehabilitation (CR) and intensive cardiac rehabilitation (ICR) are secondary prevention interventions for cardiovascular disease (CVD) with a class 1a indication yet suboptimal utilization. To date, there are only three approved ICR programs. Alternative programing should be explored to increase enrollment and adherence in these interventions. OBJECTIVES This study aims to evaluate the effectiveness of the Strong Hearts program in cardiovascular patients following a major cardiovascular event. METHODS One hundred ninety-seven (n = 197) participants were enrolled in this prospective, nonrandomized study. Patients were eligible for participation if they were referred by a physician after a major cardiovascular event, defined as any of the following: (1) acute myocardial infarction (MI) within the preceding 12 months; (2) current stable or unstable angina pectoris; (3) heart valve procedure; (4) percutaneous intervention of any kind; (5) heart transplant; (6) coronary artery bypass grafting (CABG); or (7) congestive heart failure (CHF) with reduced or preserved ejection fraction. Participants were asked to attend program visits four times per week for 9 weeks. Visits consisted of individualized exercise and intensive healthy lifestyle education. Paired t tests were utilized to compare pre- and postprogram outcome measures. RESULTS One hundred twenty-eight (n = 128) participants completed the program within the 9-week time frame and their outcome measures were included in the data analysis. Among this, 35.2% participants were female and 64.8% were male. The mean age was 65 (range, 19-88). Qualifying diagnoses were percutaneous coronary intervention (PCI; 60, 46.9%), CABG (33, 25.8%), angina (24, 18.8%), valve procedures (8, 6.2%), and CHF (3, 2.3%). After implementation of the intervention, statistically significant decreases in weight (P < .001), body mass index (BMI, P < .001), waist circumference (P < .001), triglycerides (P = .01), systolic blood pressure (SBP, P <.001), diastolic blood pressure (DBP, P = .002), total fat mass (P < .001), Dartmouth Quality of Life Index P < .001), and cardiac depression scores (P = .044) were detected. In other instances, there were statistically significant increases across time for the clinical parameters of high-density lipoprotein (HDL, P = .02), Vitamin D (P = .001), metabolic equivalents (METS, P < .001), Duke activity scores (P < .001), and Rate Your Plate nutrition scores (P < .001). There were no significant changes across time for total cholesterol (P = .17), low-density lipoprotein (LDL, P = .21), A1c (P = .27), or dual-energy X-ray absorptiometry (DXA) total lean mass (P = .86). CONCLUSIONS The 9-week structured program resulted in significant cardiovascular benefit to patients with CVD by reducing cardiac risk factors, increasing exercise capacity, and improving quality of life.
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The State of the Absorb Bioresorbable Scaffold: Consensus From an Expert Panel. JACC Cardiovasc Interv 2018; 10:2349-2359. [PMID: 29216997 DOI: 10.1016/j.jcin.2017.09.041] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Revised: 08/31/2017] [Accepted: 09/21/2017] [Indexed: 12/26/2022]
Abstract
Significant progress has been made in the percutaneous coronary intervention technique from the days of balloon angioplasty to modern-day metallic drug-eluting stents (DES). Although metallic stents solve a temporary problem of acute recoil following balloon angioplasty, they leave behind a permanent problem implicated in very late events (in addition to neoatherosclerosis). BRS were developed as a potential solution to this permanent problem, but the promise of these devices has been tempered by clinical trials showing increased risk of safety outcomes, both early and late. This is not too dissimilar to the challenges seen with first-generation DES in which refinement of deployment technique, prolongation of dual antiplatelet therapy, and technical iteration mitigated excess risk of very late stent thrombosis, making DES the treatment of choice for coronary artery disease. This white paper discusses the factors potentially implicated in the excess risks, including the scaffold consideration and deployment technique, and outlines patient and lesion selection, implantation technique, and dual antiplatelet therapy considerations to potentially mitigate this excess risk with the first-generation thick strut Absorb scaffold (Abbott Vascular, Abbott Park, Illinois). It remains to be seen whether these considerations together with technical iterations will ultimately close the gap between scaffolds and metal stents for short-term events while at the same time preserving options for future revascularization once the scaffold bioresorbs.
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Nanoclusters and nanolines: the effect of molybdenum oxide substrate stoichiometry on iron self-assembly. NANOTECHNOLOGY 2017; 28:205602. [PMID: 28375847 DOI: 10.1088/1361-6528/aa6b50] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The growth of Fe nanostructures on the stoichiometric MoO2/Mo(110) and oxygen-rich MoO2+x /Mo(110) surfaces has been studied using low-temperature scanning tunnelling microscopy (STM) and density functional theory calculations. STM results indicate that at low coverage Fe nucleates on the MoO2/Mo(110) surface, forming small, well-ordered nanoclusters of uniform size, each consisting of five Fe atoms. These five-atom clusters can agglomerate into larger nanostructures reflecting the substrate geometry, but they retain their individual character within the structure. Linear Fe nanocluster arrays are formed on the MoO2/Mo(110) surface at room temperature when the surface coverage is greater than 0.6 monolayers. These nanocluster arrays follow the direction of the oxide rows of the strained MoO2/Mo(110) surface. Slightly altering the preparation procedure of MoO2/Mo(110) leads to the presence of oxygen adatoms on this surface. Fe deposition onto the oxygen-rich MoO2+x /Mo(110) surface results in elongated nanostructures that reach up to 24 nm in length. These nanolines have a zigzag shape and are likely composed of partially oxidised Fe formed upon reaction with the oxygen-rich surface.
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Atomically resolved STM imaging with a diamond tip: simulation and experiment. NANOTECHNOLOGY 2014; 25:025706. [PMID: 24334653 DOI: 10.1088/0957-4484/25/2/025706] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The spatial resolution of a scanning tunneling microscope (STM) can be enhanced using light element-terminated probes with spatially localized electron orbitals at the apex atom. Conductive diamond probes can provide carbon atomic orbitals suitable for STM imaging with sub-Ångström lateral resolution and high apex stability crucial for the small tunneling gaps necessary for high-resolution experiments. Here we demonstrate that high spatial resolution can be achieved in STM experiments with single-crystal diamond tips, which are generally only considered for use as probes for atomic force microscopy. The results of STM experiments with a heavily boron-doped, diamond probe on a graphite surface; density functional theory calculations of the tip and surface electronic structure; and first-principles tunneling current calculations demonstrate that the highest spatial resolution can be achieved with diamond tips at tip-sample distances of 3-5 Å when frontier p-orbitals of the tip provide their maximum contribution to the tunneling current. At the same time, atomic resolution is feasible even at extremely small gaps with very high noise in the tunneling current.
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Growth and ordering of Ni(II) diphenylporphyrin monolayers on Ag(111) and Ag/Si(111) studied by STM and LEED. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2012; 24:045005. [PMID: 22223550 DOI: 10.1088/0953-8984/24/4/045005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The room temperature self-assembly and ordering of (5,15-diphenylporphyrinato)nickel(II) (NiDPP) on the Ag(111) and Ag/Si(111)-(√3 × √3)R30° surfaces have been investigated using scanning tunnelling microscopy and low-energy electron diffraction. The self-assembled structures and lattice parameters of the NiDPP monolayer are shown to be extremely dependent on the reactivity of the substrate, and probable molecular binding sites are proposed. The NiDPP overlayer on Ag(111) grows from the substrate step edges, which results in a single-domain structure. This close-packed structure has an oblique unit cell and consists of molecular rows. The molecules in adjacent rows are rotated by approximately 17° with respect to each other. In turn, the NiDPP molecules form three equivalent domains on the Ag/Si(111)-(√3 × √3)R30° surface, which follow the three-fold symmetry of the substrate. The molecules adopt one of three equivalent orientations on the surface, acting as nucleation sites for these domains, due to the stronger molecule-substrate interaction compared to the case of the Ag(111). The results are explained in terms of the substrate reactivity and the lattice mismatch between the substrate and the molecular overlayer.
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Abstract
The recent fervor surrounding the introduction of drug-eluting stents into the practice of cardiology has proven to be problematic. The experience with the Cypher Sirolimus-Eluting Coronary Stent (Cordis Corp., Miami Lakes, FL) at Arkansas Heart Hospital progressed from anxious anticipation to complete removal of the stent from inventory in a 6-month period. Several cases involving edge dissection and subacute thrombosis were the catalyst for the decision to cease use of the device. While new products may entice, each new modality must be approached with measured enthusiasm. Drug-eluting stents are first-generation devices that may have unexposed flaws when used as first-line treatment in routine practice. The first-generation Cypher stent, as with many new devices, offers treatment-not a cure-for coronary atherosclerosis and enhances the desire for an evolved product.
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Usefulness of optical coherent reflectometry with guided radiofrequency energy to treat chronic total occlusions in peripheral arteries (the GRIP trial). Am J Cardiol 2004; 94:1081-4. [PMID: 15476633 DOI: 10.1016/j.amjcard.2004.07.044] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2004] [Revised: 07/01/2004] [Accepted: 07/01/2004] [Indexed: 10/26/2022]
Abstract
Optical coherent reflectometry, a forward-looking, fiberoptic-guided device was used in 72 patients to direct radiofrequency energy across the central intraluminal portion of 75 chronic total occlusions in peripheral arteries (iliac, femoral, and popliteal) that failed attempts with conventional guidewires. The system was successful in crossing 76% of the chronic total occlusions with no clinical perforations or distal embolizations, and complications consisted of a single dissection greater than or equal to grade C.
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How much "UFC" is really cortisol? Clin Chem 2000; 46:793-4. [PMID: 10839766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
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Abstract
BACKGROUND Although light therapy has become the accepted treatment for patients suffering from seasonal affective disorder (SAD, winter depression), almost 40% of these patients do not respond, and require an alternative treatment. METHODS The therapeutic effects of light versus tryptophan on SAD were studied in a repeated measures design in 13 SAD patients (11 women, 2 men). Light therapy for 2 weeks or tryptophan for 4 weeks was given, separated by a one week washout period. All were assessed with the modified Hamilton Depression Rating scale (SIGH-SAD) at the beginning and end of each treatment. RESULTS Four (31%) of the patients did not respond to either therapy. Four tryptophan-resistant patients responded to light therapy, while one light therapy-resistant patient responded to tryptophan. Relapse occurred rapidly after stopping light therapy but not after stopping tryptophan therapy. CONCLUSIONS There were significant therapeutic effects of both light (p = 0.012) and tryptophan (p = 0.014) on SAD, which were not significantly different from each other. There may be a time difference between the residual pharmacokinetic effects after stopping therapy. LIMITATIONS The groups studied were small. This was an open study. CLINICAL RELEVANCE Tryptophan was equally effective to light therapy in treating SAD, but relapse after withdrawal of tryptophan probably occurs more slowly.
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Neuroendocrine responses to inhibitors of steroid biosynthesis in patients with major depression resistant to antidepressant therapy. CANADIAN JOURNAL OF PSYCHIATRY. REVUE CANADIENNE DE PSYCHIATRIE 1998; 43:279-86. [PMID: 9561317 DOI: 10.1177/070674379804300307] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
OBJECTIVE Patients with major depression frequently have high cortisol levels and resistance to dexamethasone. We sought to determine to what extent major depression might be influenced by inhibitors of steroid biosynthesis and to study the endocrine changes produced. METHOD After drug washout, 20 treatment-resistant patients with major depression were given aminoglutethimide, metyrapone, and/or ketoconazole, along with a small dose of cortisol for 8 weeks. Hamilton Depression Rating Scale (HDRS) ratings, 8:00 AM cortisol dehydroepiandrosterone sulfate (DHAS), adrenocorticotropin (ACTH), and testosterone levels were followed weekly or oftener. A dexamethasone suppression test (DST) was conducted before and after treatment. RESULTS Seventeen patients (85%) completed the course of treatment, and a significant mean drop (P < or = 0.0001) of 50% in the HDRS score occurred by 7 weeks of treatment. Cortisol levels fluctuated widely and were often still high after the patient had improved clinically. Dehydroepiandrosterone sulfate levels fell more uniformly and were found to be a useful indicator of compliance and, to some extent, efficacy with aminoglutethimide and ketoconazole therapy. The correlation between DHAS and HDRS (r = 0.94) was significant (P = 0.02). Testosterone levels in men fell with ketoconazole but returned promptly to normal at the end of treatment. Adrenocorticotropin levels were normal or elevated, depending on the assay used, and rose (P = 0.07; n = 13) in most subject during therapy. Of the 6 responders who had nonsuppressor DSTs before starting therapy, 5 had reverted to normal 1 to 2 weeks following cessation of therapy (P = 0.0006). CONCLUSIONS Abnormal metabolism of adrenocortical steroids may perpetuate depression, and alterations of synthesis or metabolism of these steroids may lead to a remission.
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Abstract
Although it has long been recognized that lymphocytes have the capacity to reduce cortisol at the C3, C5, and C20 positions, the specificity and the physiological variation of these reactions have received little attention. We have shown that such reactions also occur with progesterone. Lymphocytes were isolated from whole blood using Percoll density gradient centrifugation. The cells were incubated for 20 h with tritiated progesterone as radioactive tracer. After extractions into ethyl acetate, the residue was subjected to high performance liquid chromatography, and the radioactivities of the separated compounds were determined. Without cells, 95-97% of the tracer added was recovered in the progesterone peak, while in the presence of 4 x 10(6) lymphocytes, this was reduced to 45-90%. The metabolites obtained included at least 10 different compounds, including those corresponding in their retention times to the neuroactive 5 alpha and 5 beta dihydroprogesterones and their 3 alpha- and 3 beta- tetrahydroprogesterone derivatives. The conversion decreased with the addition of other steroids such as testosterone, cortisol, and corticosterone, suggesting that these steroids are metabolized by the same enzymes. When the cells from two pregnant patients were combined and incubated with tracer, and with and without nonradioactive progesterone, no peaks were detected by two progesterone radioimmunoassays in the absence of added nonradioactive progesterone, while in its presence three peaks corresponding to 5 alpha-dihydroprogesterone, 3 alpha-hydroxy-5 alpha-pregnane-20-dione and 3 beta-hydroxy-5 alpha-pregnane-20-dione eluted before the P peak. Their identities were confirmed using the two different progesterone radioassays that cross-reacted with these metabolites. The highest mean conversion (44.7% +/- 3.2 SE) was found with the lymphocytes of pregnant women and with that of one lactating woman (50%). Conversions by lymphocytes of women in the follicular phase (29.3% +/- 1.3 SE) were significantly lower than those in pregnancy (P = 0.014) but did not differ significantly (P > or = 0.05) from those of women in the luteal phase (22.2% +/- 3.4 SE), those of postmenopausal women (23.5% +/- 4.9 SE), or of men (22.5% +/- 2.4 SE). Lymphocytes appear to provide a hitherto unrecognized but possibly important source of neuroactive steroids.
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Antiglucocorticoid therapies in major depression: a review. Psychoneuroendocrinology 1997; 22 Suppl 1:S125-32. [PMID: 9264159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
In major depression there are two well-documented biochemical abnormalities: hypercortisolism, and its resistance to dexamethasone suppression. It therefore seems reasonable to see if giving drugs which interfere with cortisol biosynthesis might bring about a remission. An open trial was begun in our institution of 20 refractory patients with major depression. Aminoglutethimide, metyrapone, ketoconazole or combinations of these drugs along with a maintenance dose of cortisol were used for eight weeks. Of the 17 completers, eleven patients were considered to have good responses and two partial responses. Four had complete remissions lasting several years. A similar study of four patients who received oral RU 486 also gave encouraging results. Two patients with obsessive compulsive disorder associated with depression showed striking improvement on aminoglutethimide combined with a serotonin re-uptake inhibitor. In addition to a case report in 1988 by Ravaris et al. of a patient hypophysectomized for previous Cushing's syndrome whose depression responded to ketoconazole, several other studies over the past five years have had similar favorable results. Wolkowitz et al. (1993) gave oral ketoconazole to 10 depressed patients for three weeks which resulted in a significant drop in their Hamilton Depression Scale ratings. O'Dwyer et al. (1995) conducted a placebo-controlled single-blind crossover study using lifetyrapone and maintenance cortisol in eight inpatients for two weeks; six responded. Thakore and Dinan (1995) studied eight inpatients using ketoconazole for four weeks; there were five responders and three partial responders. Anand et al. (1995) conducted a four-week double-blind trial of ketoconazole in a single treatment-refractory patient with good results. Arana et al. (1995) used a different approach but one which also leads to suppression of endogenous corticosteroids-i.e. short-term dexamethasone suppression (4 mg/day for four days). When tested at 14 days, 7/19 of the dexamethasone group had responded well while only 1/18 of the placebo group had responded. While these studies have shortcomings, antiglucocorticoid therapy appears to be an effective tool in the treatment of major depression. Possible mechanisms are discussed, and a unifying hypothesis is attempted.
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Potentiation of fluoxetine by aminoglutethimide, an adrenal steroid suppressant, in obsessive-compulsive disorder resistant to SSRIs: a case report. Prog Neuropsychopharmacol Biol Psychiatry 1996; 20:1067-79. [PMID: 8888111 DOI: 10.1016/0278-5846(96)00084-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
1. The role of serotonin in the aetiology of obsessive compulsive disorder (OCD) has been established through considerable indirect evidence (Landry and Chouinard, 1990). The strongest evidence comes from the fact that drugs known to be serotonin-selective reuptake inhibitors (SSRIs) have been found to be useful in the pharmacotherapy of OCD (Landry and Chouinard, 1990). 2. The authors investigated a new treatment approach by adding an adrenal steroid suppressant to a SSRI, fluoxetine, in the case of a severe obsessive-compulsive patient who was drug-resistant to clomipramine and SSRIs. 3. We found that the combination of aminoglutethimide 250 mg qid and fluoxetine 40 mg die significantly improved the patient's condition. Moreover, during a four and a half year period, each time we tried to decrease either fluoxetine or the steroid suppressant, the patient started to relapse, suggesting that the adrenal steroid suppressant had a potentiating effect on the SSRI.
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Abstract
Twenty patients, diagnosed as suffering from treatment-resistant major depression, were treated with one or more drugs that decrease corticosteroid biosynthesis. Nine were psychotic, 11 nonpsychotic. Seventeen completed the treatment (8 psychotic, 9 nonpsychotic); 13 responded (5 psychotic, 8 nonpsychotic; 11 responded completely (i.e., a drop in the Hamilton Depression Scale of at least 50%, to < or = 15), and 2 responded partially. The mean age of the responders (45.2 +/- 12.6 years) did not differ significantly from that of the nonresponders (48.7 +/- 12/3). Data were analyzed in the following categories; (1) the presence or absence of psychosis, (2) response or nonresponse to treatment, and (3) the drug(s) used (aminoglutethimide, ketoconazole, or a combination of either of these with metyrapone). The patients improved over time on the Hamilton Depression Scale independent of the medication used. Responders demonstrated improvement in mood, insomnia, anxiety, diurnal variation, paranoia and obsessive compulsiveness. Nonpsychotics responded better than psychotics.
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Possible use of glucocorticoid receptor antagonists in the treatment of major depression: preliminary results using RU 486. J Psychiatry Neurosci 1993; 18:209-13. [PMID: 8297920 PMCID: PMC1188541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
The rationale for the use of anti-glucocorticoids in the treatment of major depression has been reviewed. Four patients with chronic severe depression who were resistant to conventional therapies were given RU 486 (200 mg/day) for periods up to eight weeks. Substantial levels of RU 486 were achieved within the first few days, and the levels fell gradually over the week after the treatment was discontinued. In three cases, treatment was stopped before the eight weeks were completed: in one case because of the appearance of a rash, in the others because of side-effects, which, in retrospect, were likely unrelated to the drug. The mean scores on the Hamilton Rating Scale for Depression of three patients decreased. Levels of adrenocorticotrophin, dehydroepiandrosterone and cortisol rose during treatment. These preliminary results suggest that glucocorticoid antagonists may be effective in the treatment of major depression and merit further exploration.
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Can further benefit be achieved by adding flosequinan to patients with congestive heart failure who remain symptomatic on diuretic, digoxin, and an angiotensin converting enzyme inhibitor? Results of the flosequinan-ACE inhibitor trial (FACET). Circulation 1993; 88:492-501. [PMID: 8339411 DOI: 10.1161/01.cir.88.2.492] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
BACKGROUND Angiotensin converting enzyme inhibitors, diuretics, and digoxin are each effective in treating congestive heart failure, but many patients remain symptom-limited on all three medications. This trial was designed to determine whether the addition of oral flosequinan, a new direct-acting arterial and venous vasodilator with possible dose-dependent positive inotropic effects, improves exercise tolerance and quality of life in such patients. METHODS AND RESULTS In a randomized, double-blind multicenter trial, 322 patients with predominantly New York Heart Association class II or III congestive heart failure and left ventricular ejection fractions of 35% or less, who were stabilized on a diuretic, angiotensin converting enzyme inhibitor, and digoxin, were treated with 100 mg flosequinan once daily, 75 mg flosequinan twice daily, or matching placebo. Efficacy was evaluated with serial measurements of treadmill exercise time, responses to the Minnesota Living With Heart Failure Questionnaire (LWHF), and clinical assessments during a baseline phase and a 16-week treatment period. After 16 weeks, 100 mg flosequinan once daily produced a significant increment in median exercise time (64 seconds at 16 weeks) compared with placebo (5 seconds), whereas the higher-dose flosequinan group did not show a statistically significant increase. Flosequinan (100 mg once daily) also improved the overall LWHF score significantly compared with placebo; both active therapies decreased the physical component, but 75 mg flosequinan twice daily was associated with a trend toward worsening of the emotional component. Most clinical assessments tended to improve on active therapy. CONCLUSIONS These results indicate that additional symptomatic benefit can be attained by adding flosequinan to a therapeutic regimen already including a converting enzyme inhibitor. Because in the future most patients will fall into this category, flosequinan is a potential adjunctive agent in the management of severe congestive heart failure. However, because recent evidence indicates that the flosequinan dose studied in the present trial has an adverse effect on survival, the benefit-to-risk ratio must be assessed in individual patients.
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Effect of maternal serum on viability and function of early human placental explants. In Vitro Cell Dev Biol Anim 1993; 29A:505-11. [PMID: 8331034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Fetal bovine serum (FBS) is frequently used to supplement chemically defined media such as Ham's F10 when studying placental explant cultures. However in vitro production of hormones is usually declining by the 2nd or 3rd day and is short-lived (7 to 10 days). In this study we explored the use of human maternal serum (HMS) from early gestation as the medium supplement to Ham's F10. Early placental hormone production was compared using two concentrations of FBS and HMS. On Day 3 of incubation, progesterone production in 10% HMS was 12-fold increased over that in 10% FBS, estradiol production was increased 10-fold, and beta hCG production more than 3-fold. When the serum concentrations were increased to 40%, the results in all cases were similar to those at 10%. Preliminary characterization studies revealed that the stimulatory activity of HMS is heat-labile, neither extractable into organic solvent (diethyl ether) nor dialyzable, suggesting that it is protein in nature. In a long-term incubation, compared with FBS (7 days), HMS permitted survival of culture up to 30 days, judged both histologically and biochemically. We conclude that HMS provides substance(s), probably protein in nature, not present in FBS or non-pregnant human serum, which are important for human placental viability and function in vivo.
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Influence of 19-nortestosterone and androgens on progesterone biosynthetic enzymes in early human placental explants. J Steroid Biochem Mol Biol 1992; 42:841-8. [PMID: 1525044 DOI: 10.1016/0960-0760(92)90092-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
We recently showed that the production of progesterone (P4) in human placental explant culture from early gestation is enhanced by treatment with 19-nortestosterone (19-NT) or with certain androgens, namely androstenedione (A-dione), 5 alpha-androstane-3 alpha,17 beta diol (3 alpha-diol) and 5 alpha-androstane-3 beta,17 beta diol (3 beta-diol). This stimulation of P4 was explored further in this study. There was little metabolism of radioactive P4 when incubated for 24 h in the presence or absence of these steroids. The role of different steroids in the regulation of P450 cholesterol side-chain cleavage enzyme (P450scc) and 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD) was evaluated by measuring the conversion of P4 derived from unlabelled 25-hydroxycholesterol and from labelled pregnenolone, respectively. The results showed that 19-NT, A-dione and 3 alpha-diol stimulated P450scc activity; however, 3 beta-diol was ineffective. While 19-NT and 3 beta-diol enhanced the bioconversion of pregnenolone to P4, A-dione and 3 alpha-diol were without effect. The initial rapid stimulation of P4 by 19-NT within 2 h of incubation was not blocked by concurrent treatment with cycloheximide (CH). However, after incubation for 24 h, 70% of the 19-NT-stimulated P4 was abolished by CH. During the same incubation period, P4 stimulation by A-dione, 3 alpha- and 3 beta-diol were completely blocked by treatment with CH. Thus our observations suggest that 19-NT-stimulated P4 accumulation is due to the combined effects on P450scc and 3 beta-HSD enzyme activities. A-dione and 3 alpha-diol increase biosynthesis of P4 by acting selectively on P450scc enzyme. However, the stimulatory action of 3 beta-diol on P4 is only at the level of 3 beta-HSD. Since CH blocks the stimulatory actions, the mechanism(s) by which androgens (A-dione, 3 alpha-diol and 3 beta-diol) and norandrogen (19-NT) augment the biosynthetic enzyme activities appears to be mediated by a process inhibited by CH. Since CH interference was absent during the initial rapid P4-stimulation by 19-NT, there may be a direct action of this steroid at the cellular level which is not dependent on new protein synthesis.
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In vitro stimulation of placental progesterone production by 19-nortestosterone and C19 steroids in early human pregnancy. J Clin Endocrinol Metab 1992; 75:838-45. [PMID: 1517375 DOI: 10.1210/jcem.75.3.1517375] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
To explore the regulatory mechanism at the critical period of the luteal-placental shift, the effects of various steroids and peptides on the production of progesterone by placental explants at 7-10 weeks were studied. Androstenedione increased progesterone production 3-fold at a concentration of 1 mumol and more than 20-fold at 18 mumol. 19-Nortestosterone (1-18 mumol) stimulated progesterone production 10- to 100-fold. 5 alpha-Androstane-3 beta,17 beta diol (1-18 mumol) stimulated progesterone production about 2- to 5-fold while its 3 alpha isomer (1-6 mumol) increased it 2-fold. Estrone, estradiol, and estriol up to a concentration of 30 mumol had no effect. Dehydroepiandrosterone sulfate (to 36 mumol), androst-5-ene-3 beta,17 beta diol (1-6 mumol), 5 beta-androstane-3 alpha,17 beta diol (1-6 mumol), and dihydrotestosterone (1-12 mumol) had no effect. Cortisol and dexamethasone (up to 12 mumol), hCG (20,000 IU/L), GnRH (4 mumol), and ACTH 1-24 (20 mumol) also had no effect. Thus, of all the compounds tested, only 19-nortestosterone and, to a lesser extent, androstenedione, 5 alpha-androstane-3 beta,17 beta diol, and 5 alpha-androstane-3 alpha,17 beta diol stimulated progesterone production in early pregnancy; at term, only 5 alpha-androstane-3 beta,17 beta diol was stimulatory. 19-Nortestosterone was found to be less efficiently aromatized compared to other androgens; since it is also known to be present in blood from pregnant women and thought to be made in the placenta, the stimulation observed may be a paracrine effect. These observations suggest that C18 and C19 steroids may be important in the regulation of progesterone synthesis by the human placenta in early pregnancy.
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Abstract
The hypercorticism frequently observed in major depression, unaccompanied by signs of Cushing's syndrome, is still poorly understood. One suicidal young woman, with very high cortisol levels and unusual resistance to dexamethasone suppression, is described. She was successfully treated with steroid suppressive drugs (aminoglutethimide, metyrapone), had a prompt and complete remission and has remained well for more than two years on no medication. This success prompted an on-going clinical trial of this therapy. The available drugs and a working hypothesis of their action are discussed.
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Abstract
The premenstrual syndrome has been described briefly and the literature relating to its pathophysiology and treatment have been reviewed. The great number of theories as to etiology and many different kinds of treatments attest to our ignorance of the exact nature of this problem. Although it is obvious that the hypothalamo-pituitary-ovarian axis must be involved, the exact mechanism whereby the symptoms come about remains elusive. Progestin in the presence of estrogen appears to be essential. Excess estrogen may aggravate the condition. The popular theory of progesterone deficiency has not been supported by double blind trials of progesterone in various forms versus placebo. Because of the important placebo effect in this condition, double blind trials are essential in the assessment of any form of treatment.
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Abstract
Patients with endogenous depression (major affective disorder) frequently have high cortisol levels, but the diurnal rhythm is usually maintained and they do not develop the physical signs of Cushing's syndrome. On the other hand, depression is a frequent feature of Cushing's syndrome regardless of etiology, and it is often relieved when the cortisol levels are reduced, by whatever means. The mechanisms of the hypercortisolemia and resistance to dexamethasone suppression commonly found in endogenous depression are poorly understood; contrary to expectations, ACTH levels are not clearly elevated. There is a striking difference in the psychiatric features seen in endogenous hypercorticism compared to those seen after exogenous administration of glucocorticoids or ACTH. This suggests that either there are other stimulating or modifying factors besides ACTH or that the steroids stimulated by ACTH or other peptides differ from those in control subjects, i.e. there may be an alteration in the metabolism of steroids in depression. Little is known about the metabolic changes or the many steroids besides glucocorticoids produced by the hyperactive steroid-producing tissue. Preliminary studies suggest that major depression may be improved by steroid suppression. It is hypothesized that steroids themselves may be important in causing and perpetuating depression.
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Response to steroid suppression in major depression resistant to antidepressant therapy. J Clin Psychopharmacol 1991; 11:121-6. [PMID: 1829098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Because of the similarities in the psychiatric symptoms of Cushing's syndrome and those of major depression, and because the former generally remits when the hyperadrenalism is alleviated, an open clinical trial of the effect of steroid suppression in major depression was undertaken. Ten patients satisfying the DSM-III-R criteria for major depression, and classified as treatment-resistant, were included. Eight patients completed the study, which consisted of discontinuation of other psychotropic drugs and 2 months' treatment with one or more steroid suppressive agent (aminoglutethimide, ketoconazole and/or metyrapone). Six were classified as responders, and two as partial responders. In six, the improvement has been sustained for longer than 5 months after withdrawing the drugs. Side effects were mild to moderate. These results provide some evidence that steroids are involved in the maintenance of major depression, and that their suppression may lead to a readjustment of the hypothalamic-pituitary-adrenal axis with remission of the depression.
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Double-blind randomized crossover trial of luteal phase estrogens (Premarin) in the premenstrual syndrome (PMS). Psychoneuroendocrinology 1990; 15:489-93. [PMID: 1966304 DOI: 10.1016/0306-4530(90)90072-h] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Eleven patients with moderate to severe premenstrual syndrome were given Premarin during the latter half of the menstrual cycle for at least two cycles, and a placebo for at least two cycles. Mental and physical symptoms were monitored daily with a self-rating scale. Premarin was significantly less effective than placebo in relieving the severity of both mental (p less than 0.02) and physical (p less than 0.02) symptoms of PMS (combined data p less than 0.01). It is concluded that luteal phase Premarin is ineffective as a treatment for PMS, and may actually aggravate the symptoms.
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The influence of various steroids on the binding of methyltrienolone (R1881) to human placenta: evidence for a second steroid-binding site which stabilizes the R1881 binding site. JOURNAL OF STEROID BIOCHEMISTRY 1989; 33:923-6. [PMID: 2601337 DOI: 10.1016/0022-4731(89)90241-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Specificity studies of the binding of R1881 to crude placental homogenate gave surprising results in that certain steroids increased the binding of [3H]R1881 rather than displacing it. While data for 'competing', i.e. displacing, steroids were similar to those reported by other authors, there have been no previous reports of increased binding due to added steroids. This increased binding was due mainly to an increase in capacity (about 10-fold). These data suggest that the placental steroid-binding protein is unusual in that there is a second steroid-binding site whose occupancy increases the stability of the protein, thereby increasing its capacity to bind R1881.
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Low polarity ligands of sex hormone-binding globulin in pregnancy. Part II--Identification. JOURNAL OF STEROID BIOCHEMISTRY 1989; 32:873-885. [PMID: 2755132 DOI: 10.1016/0022-4731(89)90466-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Certain previously unrecognized ligands of SHBG of low polarity in pregnancy were identified. They include two weakly bound compounds: 5 alpha-pregnane-3,20-dione and progesterone; and two strongly bound substances, 2-methoxyestrone and a new steroid, estradienolone (17 beta-hydroxy-1,5-estradiene-3-one). The identification of the first three peaks was based on chromatographic elution patterns, binding characteristics and gas chromatography-mass spectrometry. The identification of the fourth peak, the new steroid, was based on similar kinds of evidence and, in addition, solubility characteristics and ultraviolet absorption spectrum.
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Low polarity ligands of sex hormone-binding globulin in pregnancy. Part I--Characterization. JOURNAL OF STEROID BIOCHEMISTRY 1989; 32:865-72. [PMID: 2755131 DOI: 10.1016/0022-4731(89)90465-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Certain previously unidentified substances of low polarity binding to the sex hormone binding globulin (SHBG) in pregnancy were investigated. This material consisted of four major peaks (designated 1a, 1b, 2 and 3) as defined in maternal serum on Sephadex LH-20 chromatography. They were characterized with respect to changes in their concentration at various gestational ages and at premature and term labour in maternal serum, cord serum, placenta and maternal urine. Levels were much higher in placenta than in serum, suggesting that all four peaks were of placental origin. In the serum of mothers not in labour, while there was a significant increase in the mean serum concentration of peak (1a + 1b) and peak 3 for 12-24 weeks to 30-38 weeks gestation, there was no significant difference in the mean level of peak 2. However, there was a significant decrease in the serum levels of peak 2, but not peaks (1a + 1b) and 3, from 30-38 weeks gestation to 39-41 weeks gestation (P less than or equal to 0.05). In the serum of mothers in premature labour (30-38 weeks gestation), the levels of peak 2 but not those of peak (1a + 1b) and 3, were decreased (P less than or equal to 0.01) compared to those not in labour. These findings are consistent with the identification of peak 1a as 5 alpha-dihydroprogesterone, peak 1b as progesterone and peak 3 as 2-methoxyestrone as described in part 2. The decrease in the levels of peak 2 (for which the identification remains unconfirmed) in association with premature and impending term spontaneous labour suggest that it may be involved in the maintenance of pregnancy.
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Identification of 20 alpha-hydroxy-5 alpha-pregnan-3-one and 20 beta-hydroxy-5 alpha-pregnan-3-one in human pregnancy urine. JOURNAL OF STEROID BIOCHEMISTRY 1989; 32:317-9. [PMID: 2921873 DOI: 10.1016/0022-4731(89)90270-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
20 beta-Hydroxy-5 alpha-pregnan-3-one and 20 alpha-hydroxy-5 alpha-pregnan-3-one were isolated and identified from a pool of urine collected from women in the third trimester of pregnancy. Following isolation by Sephadex LH-20 and HPLC, the identity of each compound was established by comparison of GC-MS data for the methyloxime-trimethylsilyl ethers with those for authentic standards.
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The effects of various hormones on human chorionic gonadotropin production in early and late placental explant cultures. Am J Obstet Gynecol 1988; 159:1220-7. [PMID: 3189456 DOI: 10.1016/0002-9378(88)90453-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Although human chorionic gonadotropin production peaks in early pregnancy, little is known of the factors regulating it at this time. We have compared human chorionic gonadotropin output in placental explants of 6 to 12 and 37 to 40 weeks' gestational age after addition of hormones on days 4 and 5 of 8 days of culture. Human chorionic gonadotropin production was sevenfold greater in early versus late cultures. In early cultures human chorionic gonadotropin output was increased threefold to fourfold by progesterone, dehydroepiandrosterone, and cortisol whereas late cultures responded only to progesterone and dehydroepiandrosterone. The output of combinations of steroids was additive or better (up to fifteenfold). Gonadotropin-releasing hormone increased human chorionic gonadotropin output only slightly (onefold to twofold) while testosterone was inhibitory (early) or ineffective (late). Estradiol had no effect. These studies demonstrate that explants of early placental tissue provide a useful model for study of human chorionic gonadotropin production, that there are many similarities but some clear differences between early and late secretion, and that steroids exert significant effects on human chorionic gonadotropin production of placental cultures.
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Profiles of ligands of sex hormone binding globulin in human serum. JOURNAL OF STEROID BIOCHEMISTRY 1988; 31:257-66. [PMID: 3419156 DOI: 10.1016/0022-4731(88)90348-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Ligands of the sex hormone-binding globulin (SHBG) in samples of human serum were extracted into diethyl ether and the dried extracts chromatographed using Sephadex LH-20 chromatography. The resulting fractions were assayed by competitive binding to SHBG against a testosterone standard. Values for dihydrotestosterone and testosterone were similar to those obtained using radioimmunoassay. While the bulk of the material in male and non-pregnant female serum corresponded to other known ligands (5-androstane-3 alpha,17 beta-diol and 5-androstene-3 beta,17 beta-diol), the quantities of material in the androstanediol and androstenediol regions exceeded the known values for these steroids in hirsute women and in late pregnancy, suggesting the presence of other steroids as well. In addition, there was a large amount of material of low polarity present in pregnancy which was not accounted for by recognized circulating ligands. A normal pattern was found in a man with Addison's disease, suggesting that the bulk of SHBG ligands in men are derived from the testis. This was also indicated by the 60-fold higher levels of testosterone and androstenediol seen in normal testicular vein serum. High values of testosterone, androstanediol and androstenediol in a woman with untreated 21-hydroxylase deficiency suggested that large amounts of these compounds (or their precursors) can be produced by the adrenal and that their production by the adrenal is regulated at least in part by ACTH.
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One-tube radiotransinassay for determination of cortisol at ambient temperature. Clin Chem 1987; 33:1137-40. [PMID: 3594840] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
After extraction of the sample (on filter paper) in the counting vial, cortisol is assayed by adding 50 microL of horse serum containing tritiated cortisol, and 2 mL of toluene scintillator, shaking for 20 min, and counting the radioactivity in a liquid-scintillation counter at ambient temperature. The method can be applied to saliva, serum, or urine--directly as wet samples or dried on the filter paper. Only inexpensive reagents, which are stable for months to years, are needed.
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Abstract
Abstract
After extraction of the sample (on filter paper) in the counting vial, cortisol is assayed by adding 50 microL of horse serum containing tritiated cortisol, and 2 mL of toluene scintillator, shaking for 20 min, and counting the radioactivity in a liquid-scintillation counter at ambient temperature. The method can be applied to saliva, serum, or urine--directly as wet samples or dried on the filter paper. Only inexpensive reagents, which are stable for months to years, are needed.
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Contrasting effects of 5 alpha- and 5 beta-pregnane-3,20-dione on the motor activity of ovariectomized rats. JOURNAL OF STEROID BIOCHEMISTRY 1987; 26:577-80. [PMID: 3586674 DOI: 10.1016/0022-4731(87)90010-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
While progesterone metabolites have long been known to be potent anesthetics in pharmacological doses, there is no available information as to their effects on behaviour at physiological levels. In this study, 5 alpha- and 5 beta-pregnanediones in silastic capsules were implanted in ovariectomized rats. Approximately 4 mg/kg/day was absorbed over a 24-day period. Rats receiving 5 beta-pregnanedione had decreased motor activity (58% control, P less than or equal to 0.001) while those receiving the 5 alpha-isomer had increased activity (143% control, P = 0.01). These studies suggest that these progesterone metabolites may be responsible for some behavioural changes.
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The effects of human chorionic gonadotropin on growth and steroidogenesis of the human fetal adrenal gland in vitro. Am J Obstet Gynecol 1987; 156:681-7. [PMID: 3030110 DOI: 10.1016/0002-9378(87)90077-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
This study examined the effects of human chorionic gonadotropin, adrenocorticotropin, human luteinizing hormone, and mouse epidermal growth factor on growth (thymidine incorporation) and steroidogenesis (dehydroepiandrosterone sulfate production) of human fetal zone adrenal cells in monolayer culture. Two preparations of human chorionic gonadotropin extracted from pregnancy urine were used, one highly purified (National Institutes of Health, CR-121) and one less pure (Sigma). Thymidine incorporation was increased twofold to tenfold in cultures exposed to the Sigma human chorionic gonadotropin preparation or to mouse epidermal growth factor as compared to control. Pure National Institutes of Health human chorionic gonadotropin and luteinizing hormone had no effect on growth. When adrenocorticotropin was added alone or in combination with Sigma human chorionic gonadotropin or mouse epidermal growth factor, growth was decreased. Dehydroepiandrosterone sulfate production was stimulated by adrenocorticotropin but not by human luteinizing hormone, human chorionic gonadotropin, or mouse epidermal growth factor. These results suggest that human pregnancy urine contains a growth factor which remains to be identified but that pure human chorionic gonadotropin has no mitogenic or steroidogenic effects on the cultured fetal zone cells of the human fetal adrenal gland.
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In vitro demonstration of in utero larval development in an oviparous parasitic nematode: Haemonchus contortus. Parasitology 1986; 93 ( Pt 2):371-81. [PMID: 3785975 DOI: 10.1017/s0031182000051532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The life-cycle of Haemonchus contortus, a pathogenic stomach nematode of sheep, is typical of those of the other members of the superfamily Trichostrongyloides, all of which require a period of development outside the definitive host. Classically, gravid H. contortus, known as strictly oviparous, releases her eggs into the abomasal lumen. The eggs are passed out in the faeces in which they hatch into the 1st-stage larvae and then develop into the infective 3rd-stage larvae. We have developed a method to study the fate of eggs within gravid worms. Using this procedure, we have shown that H. contortus may also exhibit viviparity with apparently normal development from the egg to the 4th larval stage taking place within the gravid female maintained in vitro. On the basis of these observations we speculate that viviparity might occur in vivo with consequent autoinfections; if so, this might explain some puzzling clinical and epidemiological features of haemonchosis, as well as the incomplete efficacy of current control measures.
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Relative binding of certain steroids of low polarity to human sex hormone-binding globulin: strong binding of 2-methoxyestrone, a steroid lacking the 17 beta-OH group. Steroids 1986; 47:373-9. [PMID: 3617115 DOI: 10.1016/0039-128x(86)90053-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The cross-reactivities for binding sites on human sex hormone-binding globulin (SHBG) of a number of steroids of low polarity, including progesterone and estrogen metabolites, were studied. Binding relative to testosterone (100%) was low (less than or equal to 3%) except for 2-methoxyestrone (81%), 3-acetoxyestradiol (16%), 4-methoxyestradiol (6%), 3 beta-hydroxy-5 beta-pregnan-3-one (5.8%), 5 alpha-dihydrodeoxycorticosterone (4.5%), deoxycorticosterone (4%), 20 alpha-hydroxy-5 alpha-pregnan -3-one (4%), 4-methoxyestrone (4%) and 5 alpha-dihydroprogesterone (3.5%). 2-Methoxyestrone is the only steroid lacking a 17 beta-hydroxyl group which binds to SHBG with strong affinity.
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Abstract
A wide variety of stressful stimuli has been shown to increase cortisol secretion. Women with post-menopausal flushes report that their flushes cause acute physical discomfort. We studied the effect of hot flushes on plasma cortisol concentrations in 7 women with frequent post-menopausal flushes. Subjects were monitored subjectively and objectively with a skin temperature recorder over a 3-h period (8:00-11:00 a.m.). The 8:00 a.m. cortisol levels were the highest. These were followed by a decline in plasma levels, suggesting the normal circadian variation in cortisol concentrations. No increase in plasma cortisol levels was found during or after the flush episodes. These results suggest that, in our experimental setting, post-menopausal flushes do not increase cortisol secretion.
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Abstract
It has been suggested that patients receiving anticonvulsant therapy have depressed thyroid function. Thyroid function was studied in 16 pregnant epileptic women who were receiving various anticonvulsants; 20 nonepileptic pregnant women served as controls. Maternal and umbilical cord blood was collected at delivery and serum thyrotropin, total thyroxine, triiodothyronine, triiodothyronine resin uptake, and free thyroxine levels were measured. The free thyroxine index was calculated from the thyroxine and triiodothyronine resin uptake data. There were no significant differences in any of the maternal parameters. In cord serum, the thyroxine level was significantly lower (p less than 0.001) in the infants of the epileptic mothers. The triiodothyronine resin uptake was slightly increased in the epileptic group (p less than 0.05) so that the free thyroxine index largely compensated for this. The thyrotropin, free thyroxine, and triiodothyronine levels did not differ between the two groups. Thus the low thyroxine values in cord blood of infants of epileptic mothers receiving anticonvulsants probably reflect an alteration in protein binding rather than a true alteration in thyroid function.
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Investigation of factors influencing 11 beta-hydroxysteroid dehydrogenase (EC 1.1.1.146) activity in midgestational human fetal lung monolayer and explant cultures. JOURNAL OF STEROID BIOCHEMISTRY 1984; 21:677-83. [PMID: 6597317 DOI: 10.1016/0022-4731(84)90030-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
We recently suggested that the 11 beta-hydroxysteroid dehydrogenase (11-HSD) activity in midgestational human fetal lung (HFL) cultures comprised at least two enzymes, one oxidative--associated with epithelial cells, the other reductive--related to fibroblast-like cells. In this study, the effects of various hormones on 11-HSD activity were studied by measuring the interconversion of [3H]cortisol and [14C]cortisone. Human chorionic gonadotrophin, placental medium, and low oxygen concentration increased the conversion of cortisone to cortisol while activity in the reverse direction remained unchanged. No effects were seen when adrenocorticotrophin, prolactin, placental lactogen, estrogens, triiodothyronine or oxytocin were added in physiological amounts.
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Abstract
The distribution of estradiol and testosterone into sex hormone-binding globulin (SHBG)-bound, albumin-bound, and unbound fractions in whole serum under equilibrium conditions at 37 degrees C is described in women with normal menstrual cycles, pregnant women, and newborn infants. The percentage of estradiol bound to SHBG was determined by equilibrium dialysis at 37 degrees C. Whole serum, 0.1 ml, was dialyzed against 0.1 ml of the same serum heated at 60 degrees C for 1 hour (a procedure shown to denature SHBG but not to affect albumin). The percentage of unbound estradiol in whole serum was measured by dialyzing native serum against an isosmotic dextran solution. Testosterone binding was studied similarly. Our findings show that SHBG is an important binder of estradiol in both pregnant and nonpregnant women. However, estradiol binding by SHBG is undetectable in the newborn infant. Testosterone is significantly bound to SHBG under all circumstances. We conclude that SHBG does play a role in the transport of estradiol in women, particularly in pregnancy.
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Fetal cortisol levels at delivery: reply to Dr. Solomon's reply. Am J Obstet Gynecol 1983; 147:474-5. [PMID: 6624823 DOI: 10.1016/s0002-9378(16)32262-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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Abstract
A review of the data for fetal cortisol levels at delivery suggests that many of the values published over the past decade are too high owing to the use of methods insufficiently specific for cortisol in cord blood. Pitfalls in the assay of cortisol have been discussed elsewhere (40). The recent use of nonspecific methods is surprising since apparently correct values were established using DIDD in the early 1960s. The high values have mainly been associated with RIA and fluorometry, which have been shown to lack specificity in human urine as well (41). The nature of the interfering material in cord serum and urine is still not entirely clear. At least part of it probably represents cortisol metabolites. The mode of delivery and anesthetic used are also important since values obtained at elective cesarean section are lower than those after vaginal delivery. The lower values at cesarean section may be due to the decreased stress to the infant, the common use of general anesthesia, and/or lower gestational age. Gestational age is very important since values in premature infants are only about half those of mature infants, and are lower in those who go on to develop the respiratory distress syndrome.
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Human fetal serum cortisol levels related to gestational age: evidence of a midgestational fall and a steep late gestational rise, independent of sex or mode of delivery. Am J Obstet Gynecol 1982; 144:276-82. [PMID: 7124842 DOI: 10.1016/0002-9378(82)90579-8] [Citation(s) in RCA: 78] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Levels of cortisol were determined in umbilical cord serum in the presence and absence of labor at various gestational ages. In the absence of labor, serum cortisol fell (P less than 0.025) from 8.4 ng/ml at 15 to 17 weeks to 4 ng/ml at 17 1/2 to 20 weeks, a change which coincides with a rapid drop in relative adrenal weight. By 35 to 36 weeks, the mean levels had risen to 20 ng/ml and there was a further increase between 37 1/2 and 40 weeks (P less than 0.01) to a mean level of 45.1 ng/ml. Data obtained at vaginal delivery after the spontaneous onset of labor over the period of 26 to 40 weeks were more variable but showed a similar pattern, with levels about twice those in the absence of labor. No differences could be attributed to sex or to the anesthetic used. Thus, there appears to be a rise in the fetal level of cortisol with gestational age in late pregnancy, whether or not labor takes place. This rise is steepest immediately before the normal time of onset of labor and cannot be attributed to the stress associated with labor.
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Cortisol-cortisone interconversion in human fetal lung: contrasting results using explant and monolayer cultures suggest that 11 beta-hydroxysteroid dehydrogenase (EC 1.1.1.146) comprises two enzymes. J Clin Endocrinol Metab 1982; 54:563-8. [PMID: 6948817 DOI: 10.1210/jcem-54-3-563] [Citation(s) in RCA: 35] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Since cortisol (F) can influence fetal lung maturation, alterations in its intracellular metabolism may be important. In fetal lung at midgestation, both the in vivo studies of Pasqualini et al. and the in vitro studies of Murphy showed the activity of the enzyme 11 beta-hydroxysteroid dehydrogenase (EC 1.1.1.146) to be strongly oxidative, converting F to its inactive analog cortisone (E). By contrast, Smith et al. observed only reductive activity (E to F) in monolayer cultures. The object of this study was to resolve this discrepancy. Human fetal lung (HFL) of gestational age 9-13 weeks was grown in monolayer cultures or as explants on grids in Ham's F-10 medium plus 10% fetal calf serum and [3H]F and [14C]E (12-20 ng/ml of each). Extracts of media were chromatographed to separate the steroids, and the percent conversion was calculated. Explants converted F to E 20-40% and maintained day 1 levels for at least 7 days of culture. E to F conversion was initially low (1-5%) and rose to 14-20% by the end of culture, corresponding to fibroblast-like outgrowth. In monolayer cultures, which appeared to consist almost entirely of fibroblast-like cells, F to E conversion was less than 10% by 5 days, while E to F conversion steadily increased to 20-85% and plateaued at confluence. Homogenates of fresh tissue demonstrated F to E but no E to F conversion, even in the presence of cofactors. Thus, it appears that when tissue structure is maintained as in the explants, HFL cells oxidize F to E by a unidirectional enzyme; activation of E to F is only expressed by HFL fibroblast-like cells in culture and does not reflect the in vivo situation.
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The absorption by the human fetus of intra-amniotically injected cortisol. JOURNAL OF STEROID BIOCHEMISTRY 1982; 16:415-7. [PMID: 7087469 DOI: 10.1016/0022-4731(82)90054-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The absorption of cortisol from amniotic fluid by mother and fetus is poorly understood. Clarification is desirable since the amniotic route might serve as the optimal means of administering glucocorticoids and other drugs to the fetus when this is warranted. To gain some idea of the extent of the fetal absorption of cortisol, tritiated cortisol was injected intra-amniotically 20 min prior to delivery of four fetuses from 11 to 21 weeks gestational age. The tissues were analyzed for cortisol and some of its unconjugated metabolites. The placenta contained about 4% and the fetus 2% of the injected dose, the bulk of the radioactivity remaining in the amniotic fluid. Cord serum levels of radioactivity varied from 2.8 to 9.3% of the amniotic fluid level. Considerable conversion to cortisone had occurred in many tissues, particularly the placenta, lung and kidney. These results suggest that intra-amniotic injection may provide an efficient means of supplying glucocorticoids to the human fetus.
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Radioenzymaticassay for some substrates and inhibitors of human placental 11-hydroxysteroid dehydrogenase. JOURNAL OF IMMUNOASSAY 1982; 3:17-30. [PMID: 6752204 DOI: 10.1080/15321818208056984] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
A radioenzymaticassay (REA) is described, using labelled cortisol and a homogenate of human placenta. Steroids which are able to compete with the tracer for conversion to the 11-keto form can be measured. Of these, 11 beta and 11 alpha-hydroxyprogesterone (11 beta-hydroxypregn-4-ene-3, 20-dione), 3 beta, 11 beta-dihydroxypregn-5-ene-20-one, 11 beta, 20 alpha-dihydroxypregn-4-ene-3-one and corticosterone are the most active, while cortisol and prednisolone are moderately active. All other steroids tested competed less than 10% as effectively as 11 beta-hydroxyprogesterone at 50% conversion with no added substrate. The sensitivity was 0.8 ng of 11 beta-hydroxyprogesterone and 5 ng cortisol. Using this REA, preliminary studies were carried out to investigate the endogenous substrates and inhibitors of 11-hydroxysteroid dehydrogenase in human fetal tissues.
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Ontogeny of cortisol-cortisone interconversion in human tissues: a role for cortisone in human fetal development. JOURNAL OF STEROID BIOCHEMISTRY 1981; 14:811-7. [PMID: 6946266 DOI: 10.1016/0022-4731(81)90226-0] [Citation(s) in RCA: 139] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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Abstract
The specificity of 7 different binding proteins (4 antibodies and 3 transins) was investigated in human urine. Pregnant and nonpregnant urine samples were extracted and chromatographed, and values were compared before and after chromatography. Without chromatography, all methods grossly overestimated the amount of cortisol present. Four methods gave higher values than the other 3 even after chromatography, possibly due to cross-reactivity with 20-dihydrocortisone which coelutes in part with cortisol. Interference also occurred in both the less polar and the more polar regions of the chromatograms with all assay systems. Values for a series of 20 urines were closely similar for the RTAs but widely divergent for the RIAs. Close correlations were found for all of the RTAs with each other and with the RIAs if simple methylene chloride extraction was used. A high degree of correlation was also found between extracted and unextracted urine values in the 4 systems studied. Cortisol values by RTA (dog transcortin) after chromatography on Sephadex LH-20 gave mean values of 20.5 +/- 9.7 microgram/day in men, 14.0 +/- 5.7 micrograms/day in cycling women, and 38.0 +/- 24.5 micrograms/day in women in late pregnancy (n = 6 in each group). It is concluded that there is no simple practical method currently available for true cortisol in urine, but that the measurement of adrenal corticoids in urine can afford an accurate reflection of adrenocortical function provided there is no gross metabolic abnormality present and that the normal range is carefully established for each particular method used.
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