Testosterone-estradiol-binding globulin in patients with Turner's syndrome: effects of estrogens and acute growth hormone administration.

The TeBG activity of plasma from patients with Turner's syndrome was measured quantitatively using polyacrylamide gel electrophoresis. Human growth hormone administration did not significantly change the plasma TeBG levels. However, oral replacement therapy with estrogens elevated plasma TeBG within 3 days; after 9 days these levels reached a maximum of three- to four-fold greater than that observed at a time prior to therapy.

Clinical pharmacology of nicorandil in patients with congestive heart failure.

Nicorandil is a nicotinamide derivative with a potential role in human therapeutics because of its potent vasodilating properties. The pharmacokinetics of oral nicorandil administration and the relationships between plasma nicorandil concentration and hemodynamic responses were examined in 25 patients with moderate to severe congestive heart failure. The dose range from 10 to 60 mg was studied. Elimination half-life for this dose range was substantially longer than that previously reported in normal volunteers. Total area under the curve increased in a curvilinear fashion with progressive dose increments, indicating a disproportionate increase in systemically available drug at higher doses. Hemodynamic responses generally correlated well with plasma nicorandil concentration, with rapid loss of cardiovascular activity corresponding to the efficient clearance of nicorandil.

Relationships between blood ethanol levels and ethanol-induced changes in cortical EEG power spectra in the rat.

Adult female Sprague-Dawley rats were implanted with chronic cortical and temporalis muscle electrodes and/or intravenous cannulas. After acute ethanol administration, dose-dependent linear declines in blood ethanol concentration were found. Ethanol-induced increases in EEG spectral power in the 0 - 4 Hz band persisted long after blood ethanol levels and declined to zero; therefore, we found no correlation. Acute ethanol administration also produced an initial drop in 8 - 13 Hz spectral power. Then, as blood ethanol levels declined, 8 - 13 Hz spectral power increased toward normal; a significant negative linear correlation was found.

Hemodynamic effects of oral nicorandil in congestive heart failure.

Twenty-five patients with congestive heart failure (CHF) underwent a double-blind randomized study of the acute hemodynamic effects of orally administered nicorandil, a newly developed vasodilator drug. A dose range of 10 to 60 mg was studied. Nicorandil, at a dose of 60 mg, caused statistically significant decreases in systemic systolic and diastolic blood pressure, right atrial pressure, pulmonary capillary wedge pressure, systemic and pulmonary vascular resistance and systolic and diastolic pulmonary arterial pressure. A brief increase in cardiac index attributable to an increase in stroke volume without a change in heart rate was also observed. A dose of 40 mg produced similar results in cardiac index and systemic and pulmonary vascular resistance, but changes in other hemodynamic parameters were much smaller in magnitude and usually not of statistical significance. No significant hemodynamic response was seen to doses of 10 and 20 mg of nicorandil. Duration of action was short with nearly all hemodynamic parameters returning close to baseline within 3 hours. This rapid decrease in activity occurred in concert with a rapid plasma clearance of nicorandil as determined by serial measurements of plasma drug concentration. This study suggests that first-dose orally administered nicorandil elicits favorable, but brief, hemodynamic effects in CHF at doses greater than or equal to 40 mg.

Continuous intravenous dosing with ciprostene using a portable pump in ambulatory patients.

Parenteral compounds present special drug delivery challenges. This open-label study evaluated a portable infusion pump as a means to deliver intravenous ciprostene, a stable prostacyclin analog. Ten patients with peripheral vascular disease and claudication received ciprostene (titrated to 120 ng/kg/min) infused over 8 hours 1 day per week for 4 consecutive weeks. Patients successfully maintained the pump strapped to the waist. The mean +/- standard deviation delivery error, with volumes of 6 to 10 mL over 8 hours, was -0.895 +/- 3.177%. Accordingly, the pump performed well with a potent drug under these clinical conditions. Headache, flushing, and infusion site irritation during infusion were the most frequent side effects. Blood pressure remained unchanged during infusion; however, heart rate increased significantly (P < .05, maximum increase was 13.9 +/- 2.1 beats per minute [mean +/- standard error of the mean]. Mean (+/- standard error of the mean) relative claudication times on treadmill remained unchanged; however, absolute claudication times increased (P < .05) from 6.6 +/- 1.8 to 10.0 +/- 2.2 minutes. Ciprostene inhibited adenosine diphosphate-induced platelet aggregation by 56.0 +/- 12.7% (mean +/- standard error of the mean). Mean template bleeding times and plasma concentrations of platelet-specific proteins (beta-thromboglobulin, platelet factor 4) did not change.

Alteration of shock titration thresholds in the cat following intrathecal substance P administration.

Substance P (SP) was injected intrathecally (10 or 100 micrograms) into cats previously implanted with nerve-stimulating electrodes and the effect on shock titration thresholds was evaluated. Elevated shock thresholds were observed in 5 of 8 cats following the 100 micrograms dose of SP. In addition, one cat exhibited a decreased threshold and two cats showed a triphasic (increase, decrease, increase) response. Overt behavioral effects of intrathecal SP were mild, but suggested that injection of the drug was aversive.

Beneficial effects of the kappa opioid receptor agonist U-50488H in experimental acute brain and spinal cord injury.

The effects of the selective kappa opioid receptor agonist U-50488H (trans-3,4-dichloro-N-methyl-N[2-(pyrrolidinyl)-cyclohexyl]- benzeneacetamide) were examined in acute head and spinal injury models. First, in a blinded protocol, male CF-1 mice were treated intravenously with either saline or U-50488H (1, 3 or 10 mg/kg) within 3-5 min following a reproducible and quantifiable moderately severe (900 g/cm) concussive head injury. Using a grip test at 1 h postinjury to evaluate the neurological status of the injured mice, U-50488H produced a dose-related improvement in early recovery compared to the saline-treated mice. The effect was significant (P less than 0.05) after the 3 or 10 mg/kg i.v. doses. A similar concussive injury markedly reduced the % of cardiac output perfusing the forebrain (cerebral blood flow). U-50488H (10 and 20 mg/kg) partially reversed this effect to a significant degree 60 min after a 20 mg/kg dose. Secondly, the effects of U-50488H on the development of progressive post-traumatic spinal cord white matter ischemia after a 500 g/cm contusive injury were studied in pentobarbital-anesthetized cats. In 4 untreated cats, there was a progressive fall in spinal cord and blood flow (SCBF) from a 10-min postinjury level of 10.5 +/- 0.7 ml/100 g/min to 6.1 +/- 0.3 (P less than 0.03 by paired t at 4 h).(ABSTRACT TRUNCATED AT 250 WORDS)

Lateral reticular formation as a site for morphine- and clonidine-induced hypotension.

The possible role of the lateral reticular formation (LRF) in morphine-induced hypotension was investigated. Morphine (5-10 micrograms) microinjected into 15 of 25 sites in the LRF of anesthetized cats reduced mean (+/- S.E.) arterial pressure by 18.4 +/- 2.1 mmHg. Morphine applied microiontophoretically on LRF neurons had a predominately inhibitory effect on LRF cells, decreasing spontaneous rate in 51%. Since the LRF has been suggested as a site of action for clonidine-induced hypotension, clonidine was also applied microiontophoretically to these neurons. Of the cells evaluated, 43% were inhibited by clonidine. Individual cells typically responded in the same manner to morphine and clonidine. An inhibition of LRF cells by morphine and clonidine is consistent with their hypotensive action and the tonic vasopressive role assigned to the LRF. Collectively, these results suggest that the LRF is a site at which morphine and clonidine may produce their hypotensive effect.

Effect of gamma carboxylation on prothrombinase inhibitory activity of catalytically inactive factor XA.

Recombinant catalytically inactive factor Xa (factor rXai) is capable of assembly into inactive prothrombinase complexes, thus serving as a competitive inhibitor (Ki = 0.3nM) of active factor Xa. In order to study the role of gamma carboxylation in prothrombinase complex assembly, we have prepared differentially gamma carboxylated factor rXai and have measured the activities of these proteins in prothrombinase complex inhibition and in extension of plasma clotting. A factor rXai preparation containing 8 out of a possible maximum of 11 g carboxyglutamic acid (GLA) residues was found to be as active as chemically inactivated plasma factor Xa which was fully gamma carboxylated. Loss of a single additional g carboxyglutamic acid in the recombinant protein, however lead to a marked loss in activity. Factor rXai preparation with 8 GLA residues is also detected by a monoclonal antibody specific for a GLA dependent epitope. Thus assembly of the factor Va/Xa complex on phospholipid membranes does not require the presence of all of the g carboxyglutamic acid residues present in the plasma protein.

A pharmacological analysis of the pathophysiological mechanisms of posttraumatic spinal cord ischemia.

A pharmacological analysis was carried out to determine the possible role of aberrant calcium fluxes, vasoactive arachidonic acid metabolites, and microvascular lipid peroxidation in the development of posttraumatic spinal cord white matter ischemia. Pentobarbital-anesthetized cats were treated intravenously 30 minutes before a 500-gm-cm contusion injury to the lumbar spinal cord with one of the following test drugs: the Ca++ channel antagonists verapamil, diltiazem, or nifedipine; the cyclo-oxygenase inhibitors ibuprofen or meclofenamate; the thromboxane A2 (TXA2) synthetase inhibitor furegrelate sodium; or the stable epoprostenol (prostacyclin, or PGI2) analogue ciprostene calcium alone or in combination with furegrelate sodium. Another group of animals was pretreated for 5 days before spinal injury with a combination of the antioxidants vitamin E and selenium in high doses. The hydrogen clearance technique was used to make repeated measurements of spinal cord blood flow (SCBF) in the dorsolateral funiculus of the injured segment before and for 4 hours after injury. In 11 untreated uninjured cats, the mean preinjury SCBF was 12.7 +/- 1.5 ml/100 gm/min. Following contusion, there was a progressive decline in SCBF to 6.8 +/- 0.4 ml/100 gm/min, or 53.5% of the preinjury level at 4 hours. In comparison, the Ca++ antagonists diltiazem and nifedipine (but not verapamil) prevented a significant posttraumatic decrease in SCBF. Similarly, both cyclo-oxygenase inhibitors (ibuprofen and meclofenamate) maintained SCBF within normal limits (10 ml/100 gm/min or greater). However, neither TXA2 synthetase inhibition nor the stable PGI2 analogue alone had a significant effect in preventing ischemia, whereas a combination of the two agents did serve to support SCBF. The most impressive preservation of posttraumatic SCBF, however, was observed in the antioxidant-treated animals. Based upon these results, a hypothesis is presented concerning the pathogenesis of posttraumatic central nervous system ischemia which integrates an injury-induced rise in intracellular Ca++, the increased synthesis of vasoactive prostanoids (such as prostaglandin F2 alpha and TXA2), and progressive microvascular lipid peroxidation.

Effects of a single large dose of methylprednisolone sodium succinate on experimental posttraumatic spinal cord ischemia. Dose-response and time-action analysis.

The ability of a single large intravenous dose of methylprednisolone sodium succinate (MPSS: 15, 30, or 60 mg/kg) to modify the evolution of lumbar spinal cord ischemia in cats undergoing a contusion injury of 500 gm-cm is examined. Repeated measurements of spinal cord blood flow (SCBF) in the dorsolateral funiculus were made via the hydrogen clearance technique before and for 4 to 5 hours after injury. The mean preinjury SCBF for all animals was 12.29 +/- 0.77 ml/100 gm/min. Following injury, SCBF began to decrease progressively in vehicle-treated animals to a level of 7.71 ml/100 gm/min, a fall of 37.3%. In contrast, cats that received a 30-mg/kg intravenous dose of MPSS at 30 minutes after injury maintained SCBF within normal limits (p less than 0.05 at 3 and 4 hours after contusion). A 15-mg/kg MPSS dose was less effective at preventing posttraumatic white matter ischemia, and a 60-mg/kg dose was essentially ineffective. It was determined that the 30-mg/kg MPSS dose was optimal for supporting SCBF when the drug was given at 30 minutes after spinal trauma, and a second series of experiments was carried out to examine the ability of this dose, when given at longer latencies, to improve decreased flow. Methylprednisolone given at 1 1/2 hours after injury in four cats produced a slight (12.7%) but transient improvement in SCBF, and when administered at 4 1/2 hours in another three animals was totally ineffective. These results show that MPSS in a 30-mg/kg dose can prevent posttraumatic spinal cord ischemia. However, it would appear that the ability of the steroid to reverse the ischemia once it has developed is limited, and probably lost, within a few hours of onset. This further suggests that the ischemic process is irreversible and underscores the need for early treatment with a large MPSS dose in order to prevent full development of ischemia and to promote neurological recovery.

Dose-related haemodynamic effects and pharmacokinetics of oral nicorandil in patients evaluated for chest pain.

We studied the acute haemodynamic dose response of nicorandil, a combined nitrate and potassium channel opener, in patients evaluated for chest pain. Single dose oral nicorandil (5, 10, 20, or 30 mg) or placebo was given to 42 right-heart catheterized patients using a randomized block design. Persistent, significant (P < 0.05) haemodynamic changes occurred primarily after 30 mg. Arterial systolic pressure fell significantly after all doses and remained reduced (maximum, 31 mmHg) up to 6 h after 30 mg; heart rate increased significantly up to 1 h. Individual haemodynamic sensitivity varied and three patients (1, 10 mg; 2, 30 mg) developed transient symptomatic hypotension associated with bradycardia. Pulmonary artery systolic pressure (diastolic was unchanged) declined significantly (maximum, 5 mmHg) up to 6 h after 30 mg whereas pulmonary capillary wedge (baseline normal) and mean right atrial pressures decreased transiently. Cardiac index (baseline normal) declined slightly (significantly after 30 mg); however, stroke volume index and stroke work index were significantly and persistently reduced after all doses. Total systemic vascular resistance declined slightly after 30 mg. Individual plasma nicorandil concentrations were variable and systemic bioavailability was reduced compared with values reported in healthy subjects. Nicorandil demonstrated cardiac unloading actions. Variable plasma concentrations, haemodynamic effects, and patient sensitivity warrant low initial doses with individual dose titration, especially if cardiac filling pressures are low.

Acute effects of increasing doses of nicorandil on renal function in man.

The effects of nicorandil, a nicotinamide derived vasodilator combining nitrate and potassium channel opener actions, on kidney function have not been determined. This study investigated changes in renal blood flow and glomerular filtration rate as estimated using simultaneous 131I-iodohippurate and 125I-iothalamate plasma clearances. Forty-two healthy subjects in sodium balance received placebo and 2.5 mg (n = 8), 5 mg (n = 9), 10 mg (n = 8), 20 mg (n = 8) or 30 mg (n = 9) nicorandil orally. Peak nicorandil plasma concentrations occurred in the first hour. Nicorandil produced dose related decreases in blood pressure with maximum reductions (mean +/- standard error of the mean) after 30 mg of -6 +/- 1 mmHg systolic and -8 +/- 2 mmHg diastolic. Renal blood flow averaged 655 +/- 28 ml/minute/1.73 m2 after placebo. Renal blood flow changed 10 +/- 11% after 2.5 mg, -6 +/- 8% after 5 mg, -12 +/- 11% after 10 mg, -11 +/- 5% after 20 mg, and 8 +/- 6% after 30 mg, however, these changes did not reach statistical significance. Glomerular filtration rate averaged 113 +/- 3 ml/minute/1.73 m2 and was unaltered after nicorandil. Nicorandil had no effect on filtration fraction but fractional excretion of sodium tended to decrease with dose. These dose-related effects of nicorandil are consistent with other mixed vasodilators. At therapeutic doses, renal perfusion and function are preserved despite reductions in systemic blood pressure by nicorandil.

Female autonomy, the family, and industrialization in Java.

PIP: It is generally argued that industrialization has an adverse affect on the position of women due to their exclusion from industrial employment and the resulting erosion of their status. This article addresses a case study of the question of gender stratification and industrialization by analyzing the relationship between factory daughters and their families in Java, Indonesia. From an initial 1-month daily survey of income and expenditures conducted among 14 workers in Nuwun, Wolf found that although they contributed 28% of their wages to the family, in cash or in kind, they overspent their wages by 40%. She then designed a more extensive survey, including questions about access to other income, debts, and savings. To determine if the relationship between daughters and family economy was related to residence, she expanded the survey to include 3 different groups of workers: commuters, migrants, and residents. Commuters lived with their parents in the agricultural village, Nuwan, and were the sole focus of the 1st income survey. Migrants were boarders in an industrialized village, Pamit, and residents walked to work. Single women are the focus of this paper due to the very different contribution daughters can potentially make to the family's welfare. The case study suggests that industrialization at the very least maintains, and may even enhance, female status within the family. To summarize, if a family can release a daughter for factory employment and can forgo the returns from her labor, there are eventual benefits for both the worker and her family. Worker-daughters are less of a financial burden on families. The savings provide surplus income that is not used for subsistence needs. Families gain tangible status goods that are displayed in the house and, at the same time, have access to insurance for crises and cash needs. Daughters, on the other hand, choose what to purchase and for whom. They gain prestige as donors of thoughtful gifts to family members, and gifts are symbols of independence. They also gain prestige as providers of emergency aid. These contributions bring them higher status than would remitting a steady but tiny flow of cash to the family economy. Wolf compares this Southeast Asian case with the East Asian experience to demonstrate the important role family systems play in mediating the effects of industrialization upon women and family change.^ieng