Local anesthetic activity and acute toxicity of N-substituted 1,2,3,4-tetrahydro-1- and 2-naphthylamines. Seven N-substituted 1,2,3,4-tetrahydro-1- and three 2-naphthylamines were prepared and tested for local anesthetic activity in the rabbit corneal reflex test and the mouse sciatic nerve block test. At 0.1 and 1%, three 1-alkylamino compounds had durations of action comparable to that of tetracaine in the rabbit corneal reflex test and were considerably more potent than lidocaine. The other four 1-alkylamino derivatives were inactive or at best minimally active. The durations of action of 1% concentrations of the three 2-alkylamino compounds were equivalent to that of 1% lidocaine in the corneal reflex test. In the mouse sciatic nerve block test, the three active 1-alkylamino compounds were considerably longer acting than either tetracaine or lidocaine. Three 1-alkylamino and the three 2-alkylamino compounds showed toxicity equal to or greater than lidocaine, while two 1-alkylamino and two 2-alkylamino compounds showed toxicity equal to or greater than tetracaine by the intraperitoneal route in mice. N-Heptyl-1,2,3,4-tetrahydro-6-methoxy-1-naphthylamine methanesulfonate was the most promising local anesthetic in these series.


Simplified GLC assay for lidocaine in plasma. A simple, rapid GLC method for the determination of lidocaine in plasma is described. After addition of mepivacaine as an internal standard, the plasma sample is deproteinated and centrifuged. The supernate is alkalinized, and the lidocaine and internal standard are extracted into a microvolume of carbon disulfide. By using GLC with a flame-ionization detector, linear concentration-response curves were obtained in the 1-6 microgram/ml range. The method can easily determine plasma concentrations at the 250-ng/ml level when a 1-ml plasma sample is analyzed.


Stability-indicating methods for quantitative determination of spironolactone using high-pressure liquid chromatography and blue tetrazolium reaction. Stability-indicating methods for the quantitative determination of spironolactone were developed. The methods are based on high-pressure liquid chromatography and a reaction with blue tetrazolium. Both methods are accurate, precise, and sensitive and gave excellent results with commercial tablets, including those containing hydrochlorothiazide in addition to spironolactone, The blue tetrazolium method cannot be used in the presence of high concentrations of either polyethylene glycols or water. Spironolactone decomposition in water or polyethylene glycol appears to follow pseudo-first-order kinetics. The decomposition constant at 65 degrees was 0.0253/day in water versus 0.115/day in polyethylene glycol ointment base USP.


Modified technique using perfused isolated guinea pig lung to determine effect of an aerosol constituent on pulmonary dynamics. Polyethylene glycol 400, a commonly used plasticizer in many cosmetic aerosol hair sprays, was tested to determine its effect on perfusion pressure, perfusion vascular flow rate, and tidal volume in the perfused isolated guinea pig lung. Negative pressure was maintained within the chamber housing the intact lungs, and initial perfusion of the pulmonary vasculature was accomplished via the right side of the heart in situ after guinea pigs were sacrificed by decapitation. Polyethylene glycol 400 was injected into the pulmonary arterial system in doses of 0.01-30 microgram/ml after pretreatment with isoproterenol (1 microgram/ml). Isoproterenol was then readministered, followed by nebulized doses of the cosmetic chemical into the trachea at 0.3, 3, and 30% concentrations. Nebulized polyethylene glycol 400 was also administered in 50, 70, and 90% concentrations. Polyethylene glycol 400 significantly increased perfusion pressure and flow rate after injection into the pulmonary arterial system of the isolated lung. In addition, nebulized administration in concentrations of 0.3-30% significantly increased the perfusion flow rate; following the 50-90% nebulized doses, a significant increase in both perfusion pressure and flow rate was observed. Tidal volume decreased, regardless of the route of administration, as increasing doses of the cosmetic constituent were delivered to the isolated lung.


Study of drug-protein binding by affinity chromatography: interaction of bovine serum albumin and salicylic acid. The affinity chromatographic technique was used to study the interaction of bovine serum albumin and salicylic acid at 3.3 +/- 1.1 degrees. Beaded agarose gel, on which the albumin was immobilized by covalent linkage, was packed in a column as an affinity adsorbent. Frontal analysis was performed on this column to evaluate the binding parameters for the interaction. The effect of albumin immobilization on drug binding was investigated by comparing the binding parameters of two affinity adsorbents, directly coupled albumin and albumin coupled through a spacer arm. The latter mode of attachment gave binding characteristics comparable to those of the soluble albumin. The method is simple and precise. The affinity adsorbent can be used repeatedly for many months for various drugs, including those that do not diffuse through dialysis membranes.


Tissue culture cytotoxicity assay for cyclophosphamide metabolites in rat body fluids. An in vitro cytotoxicity assay for cyclophosphamide metabolites in rat body fluids is described. Of the two tissue culture tumor cell lines employed, the Walker-256 rat carcinosarcoma was more sensitive to metabolite levels than the L-1210 mouse lymphocytic leukemia. The Walker-256 system detected cyclophosphamide metabolite levels two orders of magnitude lower than the commonly used 4-(p-nitrobenzyl)pyridine analytical procedure.


Evidence for a trimodal pattern of acetylation of isoniazid in uremic subjects. Isoniazid metabolic clearance values were calculated retrospectively and plotted on a frequency distribution histogram. A trimodal distribution pattern was observed. According to a two-allele codominant model, the mean clearance values of the slow and rapid acetylators closely predicted the mean clearance value for the intermediate acetylators. The potential clinical implications of identifying intermediate and rapid acetylators of isoniazid and its use in renal failure are discussed.


Synthesis and hypotensive activity of a series of 2-substituted 5,6-dimethoxyindazoles. The synthesis and hypotensive activity in the dog of a series of 2-substituted 5,6-dimethoxyindazoles are reported. Structure-activity relationships for this class of compounds are discussed. Indazoles containing the diethylaminoethyl, 3-pyridyl, and hydroxyethyl functions in the 2-position were the most effective in lowering blood pressure for the longest times (greater than 270 min).


New 5-hydroxy-2-indolecarbohydrazides as platelet aggregation inhibitors in ethylene glycol. The effect of ethylene glycol on blood platelet aggregation was examined using a previously described method. This method also was used to investigate several derivatives of 2-indolecarbohydrazide in vitro. All compounds inhibited platelet aggregation induced by collagen, epinephrine, or adenosine diphosphate at concentrations below 5 x 10(-4) M.


Assay of mercaptopurine in plasma using paired-ion high-performance liquid chromatography. A sensitive, quantitative, and specific high-performance liquid chromatographic method for mercaptopurine in plasma is described. The analysis, in which mercaptopurine and the internal standard, 6-methylthio-2-hydroxypurine, are chromatographed as ion-pairs with heptane-sulfonic acid, employs a simple and rapid sample preparation based on deproteination using 60% trichloroacetic acid. Quantitation of plasma samples to 0.2 microgram of mercaptopurine/ml is reported. The retention times of the major metabolites do not interfere.


Erythromycin VI: kinetics of acid-catalyzed hydrolysis of erythromycin oxime and erythromycylamine. Kinetic data were obtained, by qualitative and quantitative analysis, of the hydrolytic degradation of erythromycin oxime and erythromycylamine separated by TLC. The pseudo-first-order rate constants were determined at three temperatures (17,26, and 36 degrees), and the temperature dependency of the reaction was studied. The activation energy for the hydrolysis and methanolysis of the compounds was calculated. The factors contributing to the differences in the reaction rate are discussed.


Rapid determination of atenolol in human plasma and urine by high-pressure liquid chromatography. A rapid, specific, high-pressure liquid chromatographic determination of atenolol in plasma and urine was developed. This method employs the high sensitivity of fluorescence detection together with selective extraction and reversed-phase chromatography to measure concentrations as low as 20 ng of drug/ml of plasma with a coefficient of variation of 3.91%. The assay is specific enough to be valid in the presence of plasma and urine substances. The detection limit (i.e., three times baseline noise) is 3 ng/ml.


Benzoyl peroxide assay using high-pressure liquid chromatography. A highly specific assay for benzoyl peroxide was developed using high-pressure liquid chromatography. A concentration curve was recorded from 0.1 to 3.0 microgram with a correlation coefficient of 0.9969. The standard deviation for 10 individual analyses of a benzoyl peroxide preparation was +/- 0.547 (1.80% RSD).


Rapid and micro high-pressure liquid chromatographic determination of chloramphenicol in plasma. A high-pressure liquid chromatographic method was developed for chloramphenicol in plasma. Plasma samples were deproteinized with 2.5 volumes of acetonitrile, and the supernates were chromatographed on a reversed-phase column, using acidified ethanol-water as the mobile phase and UV spectrophotometry for detection. The sensitivity for accurate quantitation of chloramphenicol was about 2.5 microgram/ml in plasma, and concentrations as low as 0.5 microgram/ml could be detected. Only about 8 min is needed for each sample. This method is specific, rapid, and sufficiently sensitive and may be useful for clinical monitoring.


Perfluorooctyl bromide concentration in plasma and tissues of beagle dogs. Plasma levels were determined frequently after single doses of perfluorooctyl bromide were administered to beagle dogs at doses of either 30.8 g/kg po or 3.9 g/kg intratracheally. The apparent first-order half-life during the terminal elimination phase was about 1 day after oral medication and about 7 days after intratracheal administration. Analysis of tissues revealed the highest concentrations of the compound in abdominal fat of dogs autopsied 4 weeks later.


Intestinal absorption of griseofulvin from a triolein digestion mixture in rats. The intestinal absorption rate of dissolved griseofulvin was determined from: (a) an aqueous phase, (b) an aqueous phase containing a micellar phase composed of taurodeoxycholate, monoolein, and oleic acid, and (c) an aqueous phase containing the micellar phase and emulsified triolein. The triolein digestion mixtures were recirculated through 20-cm segments of in situ rat jejunum. Lipid concentrations were maintained constant by infusing the lipids into the digestion mixture at the same rate as they disappeared. Griseofulvin distribution among the aqueous, micellar, and oil phases was determined by solubility and equilibrium dialysis experiments. Analysis with a linear kinetic model indicated that griseofulvin absorption from the micellar and oil phases was negligible compared to its absorption from the aqueous phase.


Ball milling as a measure of crushing stength of granules. When granules are milled in a ball mill, the size decrease follows a modification of Kick's law. The Briggsian decay constant, here denoted as the attritional crushing strength, shows correlation with the Harwood-Pilpel crushing strength. Both crushing strengths show a correlation with the amount of granulating agent (povidone) added to the granulation, i.e., the more povidone added, the harder the granule.


General treatment of competitive binding of small molecules to macromolecules as applied to dynamic dialysis: theoretical analysis. A mathematical analysis of the dynamic dialysis process is presented, demonstrating how the process can be applied generally to study competitive and noncompetitive binding between small molecules and macromolecules. A law of mass action model for competitive binding with independent sites and classes with equivalent sites (CIE) is considered as a specific case without loss of generality. The escape profiles of two compounds are calculated to illustrate the effect of an increasing degree of binding competition. Noisy data are generated using the CIE model to test the presented method of estimating competitive binding parameters. The parameters estimated by the nonlinear regression technique came close to the true values, considering the degree of noise added to the exact dialysis data. A transformation approach is presented, enabling initial estimates of the binding parameters in the CIE model to be determined by multiple linear regression, thereby eliminating the main problem in the nonlinear estimation. The presented method of analysis is extended to strongly bound compounds, which also bind significantly to the dialysis membrane.


Analysis of steroid phosphates by high-pressure liquid chromatography: betamethasone sodium phosphate. A sensitive, automatable high-pressure liquid chromatographic procedure is presented for the determination of steroid phosphates. Quantitation is described for betamethasone sodium phosphate in dosage forms in the presence of polar excipients. The separation of a multicomponent mixture of steroid phsophates also is reported.


Theophylline bioavailability following chronic dosing of an elixir and two solid dosage forms. Theophylline bioavailability following chronic dosing of an elixir and two commercial tablet formulations (I and II) relative to an acute dose of elixir was evaluated in healthy volunteers. Both tablet formulations contained ephedrine. In addition, Tablet I contained hydroxyzine hydrochloride, and Tablet II contained phenobarbital. The mean area under the serum concentration-time curve (AUC) calculated either from time 0 leads to infinity for a single dose or over one dosing interval after repetitive doses was the highest after chronic administration of the elixir. The AUC after chronic elixir, in fact, was statistically different from the values after acute elixir (p less than 0.05) and Tablet II (p less than 0.05). There was, however, a large variation in the elimination half-life among the four theophylline treatments. The mean t 1/2 was the longest after chronic elixir followed by Tablet I, Tablet II, and acute elixir. The AUC values for the four treatments, when corrected for differences in t 1/2, were no longer significantly different, indicating that the extent of theophylline absorption was essentially the same from all three tested products. The time to peak and the peak serum concentration also did not differ among treatments. The prolongation in t 1/2 following chronic treatment with the elixir and its subsequent shortening during tablet administration suggest an initial inhibition followed by induction of theophylline metabolism. The changes may be due to the prolonged treatment with theophylline itself or the other drug ingredients in the dosage form.


Cloprednol bioavailability in humans.

Cloprednol bioavailability in humans. The bioavailability of cloprednol, a new systemic corticosteroid, was examined in a 12-subject crossover study in which two capsules, a tablet, and a solution were tested. Plasma was analyzed for cloprednol by a GLC-mass spectrometric method. The biological half-life, peak plasma concentration, peak time, plasma concentration at all sampling times, and plasma areas were evaluated for differences (p less than or equal to 0.05) in comparisons of pairs among the four formulations. An analysis of variance revealed that cloprednol was absorbed to the same extent from all formulations and rapidly cleared from the plasma with a half-life of 1.86 +/- 0.36 (SD) hr. All plasma profile parameters from the solid dose formulations were the same, demonstrating bioequivalence in both rate and extent of absorption. Significant differences were observed between the solution and solid dose formulations with respect to peak time, 15-min plasma concentration, and 0-30 min area, indicative of faster absorption from the solution; however, total plasma areas were the same for all four formulations. Comparison of plasma cloprednol levels in this study to those of a prior intravenous-oral dose study suggests that cloprednol was completely bioavailable from all formulations.


Quantitative determination of prednisone and prednisolone in human plasma using GLC and chemical-ionization mass spectrometry. A method for the quantitative determination of prednisolone and prednisone in human plasma utilizing GLC and chemical-ionization mass spectrometry is described. Corticosteroids are extracted from plasma into ether, and the extract is purified either by passing through a magnesium silicate column or by solvent partitioning. Interference from endogenous hydrocortisone is removed by selective derivatization with Girard Reagent T. Following derivatization, prednisolone can be quantitatively separated from the water-soluble hydrocortisone derivative by simple solvent partitioning. The extracted prednisone and prednisolone are converted to their corresponding methoxyimino trimethylsilyl derivatives, and subjected to GLC-mass spectrometry. Prednisone and prednisolone plasma profiles following a 15-mg oral dose of prednisone in a human volunteer are presented. The method can measure prednisone and prednisolone in plasma at the nanogram per milliliter level.


Kinetic and mechanistic studies of blue tetrazolium reaction with phenylhydrazines. The reaction kinetics of blue tetrazolium with selected arylhydrazines were investigated under pseudo-first-order conditions. The reaction rate constants were obtained at various temperatures, and the enthalpy (8.4-11.2 kcal/mole) and entropy (-38--45 eu) of activations were calculated. A Hammett plot yielded a straight line with a slope of 0.52. The reaction was inhibited by atmospheric oxygen and iodine. A free radical mechanism is presented.


Effect of hydrophilization of hydrophobic drugs on release rate from capsules. The release of poorly soluble hydrophobic drugs from capsules can be improved significantly by the creation of a hydrophilic surface by intensive mixing of the hydrophobic drug with a small amount of a solution of a hydrophilic excipient. This technique was introduced previously for the production of microgranules. The data presented indicate that the hydrophilic material is mechanically distributed over the hydrophobic surface. The creation of hydrophilic capillaries in a capsule or tablet allowed the rapid penetration of the dissolution fluid, resulting in a dispersion of well-wetted particles, so that the maximum surface area of the powder was exposed to the dissolution medium. Moreover, hydrophilization of hydrophobic drugs has the important benefit that the release rate from capsules is independent of the surface tension of the dissolution medium.


Kinetics of aggregation of human platelets. A study of the aggregation kinetics of human platelets using an electronic counting device is reported. The experimental data were analyzed quantitatively by a physical model, which assumed that the initial disappearance rate of single platelets versus time fitted a second-order type of aggregation with respect to platelet number. The mechanism of aggregation was surface barrier controlled. Thus, the aggregation rate constants in different adenosine diphosphate concentrations (1.5-9.0 microgram) were 10-100 times greater than  the rate constant (6.6325 x 10(-12) cm3/sec) for a diffusion-controlled mechanism, were smaller in the surface-barrier-controlled process and ranged from 0.00741 to 0.0467. The extent of aggregation was indicated by the calculation of a sticking probability constant as determined by the barrier. Adenosine diphosphate induced a rapid aggregating effect. Prostaglandin E1 produced the most drastic deaggregating effect as compared to dinoprostone (prostaglandin E2) and dinoprost (prostaglandin F2alpha). Aspirin completely blocked the aggregating effect of arachidonic acid.


Synthesis of spirofluorenes of biological interest. 1'-Substituted spiro[fluorene-9,3'-pyrrolidine-2',5'-diones], 1',1''' - (1,4-piperazinediyldimethylene) bis[spiro[fluorene-9,3'-pyrrolidine-2',5'-dione]], and 1'-arylspiro[fluorene-9,3'-pyrrolidines] were synthesized from spiro[fluorene-9,3'-tetrahydrofuran-2',5'-dione]. The rat passive cutaneous anaphylaxis assay showed that one compound possessed slight antiallergic activity. Synthesis of 3-substituted 1-aryl-4-oxospiro[azetidine-2,9'-fluorenes] and 1,1''-p-phenylenebis[4-oxospiro[azetidine-2,9'-fluorenes]] was achieved via the reaction of appropriate N-fluorenylideneanilines with tert-butylcyanoketene and cyclopentamethyleneketene, respectively.


Effect of diazepam on cognition via pupillometry. Continuous pupillary readings in response to a random-digit cognition task were obtained for 20 male subjects. Ten subjects were given 10 mg of diazepam, and 10 subjects were given placebos. Additional pupillary curves were recorded for both groups at 1 and 2 hr and compared to the initial curve. Subjects were required to repeat the exact sequence of verbalized randomized digits as a measure of performance. The results indicated that the diazepam treatment group differed significantly from the placebo group in terms of a depressed pupillary response. Furthermore, the performance recall measure was significantly reduced in the diazepam group. The relationships were clarified by an analysis of covariance and variance.


Impurities in drugs II: meperidine and its formulations. Three lots of meperidine hydrochloride, seven lots of meperidine tablets, and 41 lots of meperidine injectables were examined for impurities by TLC. Impurities found were ethyl 1-benzyl-4-phenyl-4-piperidinecarboxylate, methyl-4-piperidinecarboxylate, ethyl-4-phenyl-4-piperidinecarboxylate, and three unidentified compounds. Not all impurities were found in every lot of drug investigated, and none of the impurities exceeded a concentration of 1% of the meperidine present.


Pyridinium- and quinolinium-2-dithioacetic acid zwitterions: antiradiation and anticancer activities. Pyridinium-, quinolinium-, and one pyrimidinium-2-dithioacetic acid zwitterions were prepared by condensation of the N-methyl heterocyclic anhydro bases with carbon disulfide. Reaction of the 2-methylpyridine methiodide anhydro base with carbon disulfide resulted in replacement of the 2-methyl group to give the 1-methylpyridinium-2-dithioacetic acid zwitterion. The 1,6-dimethylquinolinium-2-dithioacetic acid zwitterion showed appreciable anticancer activity against P-388 lymphocytic leukemia in mice, but the other zwitterions tested showed no activity. No antiradiation activity was found for 1-methyl-pyridinium-2-dithioacetic acid zwitterion.


Effect of local anesthetics on electrically excitable bilayer lipid membranes. The effect of three local anesthetics on the action potential of electrically excitable bilayer lipid membranes was studied. The synthetic action potential of bilayers was abolished at drug concentrations roughly identical to those abolishing the action potential in nerves. The threshold depolarizing constant current pulse triggering the synthetic action potential was increased by slightly lower concentrations of these local anesthetics. It is suggested that the anionic channels, which are responsible for the rising phase of the action potential in bilayers, are affected preferentially by these drugs.


Binding of butylated hydroxyanisole to human albumin using a novel dynamic method. To study the interaction of butylated hydroxyanisole with various body tissues, a fully automated dynamic method was developed for the determination of plasma protein binding constants at 37 degrees, using membrane filtration equipment designed for dissolution rate studies. Appropriate equations were derived for the calculation of the free drug concentration from comparative diffusion rates across sealed dialysis sacs. A monoexponential equation described the diffusion in the absence of proteins, and a biexponential equation was fitted to diffusion from the drug-protein complex. The Scatchard and double-reciprocal plots were developed for butylated hydroxyanisole. A high degree of reproducibility was obtained for the calculation of protein binding constants (K = 2.4 - 2.9 X 10(4) and n = 1.4 - 1.32). The magnitude of these binding-constants suggests that any change in protein binding can have a significant effect on the distribution of butylated hydroxyanisole throughout the body, such as may be brought about by the common variations in the amount ingested.


Molecular interaction between E-prostaglandins and selected polymers and its potential utilization in oral dosage form design. Coacervate formation was observed between some E-prostaglandins and povidone in acetonitrile. This molecular interaction was studied using differential scanning calorimetry, IR spectrophotometry, and light microscopy. The structural requirements for coacervate formation between E-prostaglandins and povidone were investigated. Possible utilization of this molecular interaction in the development of E-prostaglandin formulations was explored. The dissolution rate of some insoluble E-prostaglandin esters increased when they were coprecipitated with povidone and polyethylene glycol. For example, the p-hydroxybenzaldehyde semicarbazone ester of 16,16-dimethyldinoprostone dissolved about 200 times faster as a povidone coprecipitate than did the control mixture. Enhancement of the dissolution rate was observed for the povidone coprecipitates of dinoprostone and its p-acetylphenyl and beta-naphthyl exters but not for the p-phenylphenyl ester. Fast dissolving dispersions of the E-prostaglandin esters also could be prepared with the water-insoluble cross-linked polyvinylpyrrolidone. This type of dispersion was nonglassy and easily dispersible in water. Thus, it might have certain advantages over the classical soluble povidone coprecipitates in terms of ease of handling. The degree of enhancement in dissolution of dispersions of cross-linked polyvinylpyrrolidone and E-prostaglandin esters is apparently dependent on the structure of the esters. The potential dissolution enhancement may be related to the strength of the interaction between the macromolecule and the esters, as indicated by the qualitative relationship between the extent of adsorption of the prostaglandins to cross-linked polyvinylpyrrolidone and the dissolution rate enhancement.


Formation of a cyclic derivative of ethacrynic acid with diazomethane. Samples of ethacrynic acid were treated with methanol-hydrochloric acid or with diazomethane. GLC and mass spectrometric analysis indicated that the methanol-hydrochloric acid reaction gave the expected methyl ester, whereas diazomethane treatment gave a compound containing an additional 14 mass units. Accurate mass measurement and PMR and IR spectra showed that this product was a cyclic derivative of the methyl ester of ethacrynic acid, methyl 4-(2,3-dihydro-4-ethyl-5-furyl)-2,3-dichlorophenoxyacetate. Either derivatization method can be used for development of an assay for ethacrynic acid.


Dissolution rates of hydrocortisone and prednisone utilizing sugar solid dispersion systems in tablet form. The utilization of ternary sugar solid dispersion systems and the incorporation of these systems into tablet dosage forms were investigated. The dispersion systems were prepared by the fusion method using 50% sucrose-50% mannitol and 50% sorbitol-50% mannitol. Other systems investigated utilized sorbitol, mannitol, and polyethylene glycol 6000 for comparison. The drug component was hydrocortisone or prednisone. The results from a modified NF XIII dissolution rate determination revealed that the mannitol system had the fastest dissolution rate, followed by sorbitol-mannitol, sucrose-mannitol, sorbitol, and finally, polyethylene gylcol 6000. The corticosteroids were stable and did not decompose during preparation of the dispersion systems or direct compression of the tablets. A short-term stability study revealed that the tablets retained their fast dissolution rates and that the tablet characteristic tests, i.e., tablet hardness, remained unchanged. The use of sugar combinations overcame some difficulties previously reported with single sugar systems.


USP dissolution III: semilogarithmic dissolution patterns of tablets in rotating-basket assemblies. The dissolution of a rapidly soluble, finely subdivided substance in a directly compressed tablet and in a wet granulated tablet was treated experimentally and compared with previous theoretical models. The dissolution curves were sigmoid with a semilogarithmic tail when concentration was plotted versus time. As predicted, the slope of the semilogarithmic plots were related to the disintegration decay constant for tablet erosion in the basket.


High-performance liquid chromatographic assay for suprofen, a potent new analgesic, in plasma. A simple, rapid, high-performance liquid chromatographic (HPLC) determination of therapeutic levels of suprofen, a potent new analgesic, in human plasma is described. After a simple extraction, the compound is analyzed by HPLC using a reversed-phase column and a UV detector. Quantitation is accomplished using an external standard; peak areas are determined by computer. An average recovery of 80.0 +/- 8.5% SD of the drug was obtained over the 0.2-20.0-microgram/ml range. Maximum sensitivity is approximately 0.1 microgram/ml. No interference is encountered from any known metabolite of suprofen.


Anticonvulsant and antiproteolytic properties of 2,5-disubstituted oxadiazoles and their inhibition of respiration in rat brain homogenates. Eight 2-(3,4-methylenedioxyphenyl)-5-arylamino1,3,4-oxadiazoles were synthesized, characterized by their sharp melting points, elemental analyses, and IR spectra, and evaluated for anticonvulsant activity. The protection afforded by oxadiazoles (100 mg/kg ip) against pentylenetetrazol (90 mg/kg sc)-induced convulsions ranged from 50 to 80%. All oxadiazoles inhibited the respiratory activity of rat brain homogenates during oxidation of pyruvate, alpha-ketoglutarate, and succinate. The presence of added nicotinamide adenine dinucleotide (NAD) to the reaction mixture during oxidation of pyruvate decreased the degree of inhibition. All oxadiazoles possessed antiproteolytic activity that was reflected by their ability to decrease trypsin-induced hydrolysis of bovine serum albumin. Such an inhibition was concentration dependent and ranged from 10.2 to 47.5 and from 15.7 to 71.8% by 0.5 and 1 mM oxadiazoles, respectively. All oxadiazoles competitively inhibited in vitro succinate dehydrogenase activity of rat brain homogenates.


New biphenyl derivatives i: 1-(4-biphenylyl)-2-phenylethylamines as potential antispasmodic and cardiovascular agents. A series of 1-(4-biphenylyl)-2-phenylethylamine derivatives was synthesized as potential antispasmodic and cardiovascular agents related to papaverine. Preliminary pharmacological tests, on isolated guinea pig ileum and anesthetized cat blood pressure, showed that the new compounds possess nonspecific inhibitory action on smooth muscles.


Light-scattering studies on bile acid salts II: pattern of self-association of sodium deoxycholate, sodium taurodeoxycholate, and sodium glycodeoxycholate in aqueous electrolyte solutions. The pattern of self-association of the bile salts sodium deoxycholate, sodium glycodeoxycholate, and sodium taurodeoxycholate was investigated in aqueous electrolyte solutions by the light-scattering technique. The turbidity of the bile salt solutions was obtained over the concentration range of 0-20 mg/ml at 25 degrees. These data were analyzed according to a monomer-micellar equilibrium model and a stepwise association model. Comparison of the light-scattering data with these models suggests that the monomer-micellar model may be inappropriate. Analysis of the data according to the stepwise association model suggests that the dihydroxy bile salts associate to form dimers, trimers, and tetramers in addition to a larger aggregate which varies in size depending on the degree of conjugation of the bile salt.


Tolerance and cross-tolerance to cocaine and d-amphetamine. The effects of cocaine (4.0-32 mg/kg) and d-amphetamine (0.5-4.0 mg/kg) on milk intake of rats were determined before and during periods of repeated daily administration of each drug. Experimental sessions consisted of 15 minutes access to 50 ml of a sweetened condensed milk solution. After the determination of the disruptive effects of single injections of cocaine or d-amphetamine on milk intake, rats were injected daily with either 16 mg/kg of cocaine 15 minutes before the session, 16 mg/kg of cocaine immediately after the session, 2.0 mg/kg of d-amphetamine 15 minutes before the session or saline before the session. During the period of repeated administration when milk intake had stabilized in each group, dose-effect functions for cocaine and d-amphetamine on milk intake were redetermined. On selected days, test doses of either drug were substituted for the usual daily injection. Test doses were separated by at least 3 days of stable intake after injection of the appropriate drug or saline. During the period of repeated administration, milk intake returned toward control levels for animals receiving daily cocaine or daily d-amphetamine before the session. Further, when the dose-effect functions for cocaine and d-amphetamine on milk intake were redetermined, a shift to the right (i.e., toward larger doses) was observed in all groups that had received drug presession during the repeated administration. This indicates that the animals became tolerant to cocaine and d-amphetamine as well as cross-tolerant to both drugs. The development of tolerance to cocaine was contingent upon the relationship of the time of injection to milk availability. Animals that had received postsession injections of cocaine during repeated administration were more sensitive to the effects of cocaine and d-amphetamine on milk intake.


Disposition of morphine in chronically infused rats: relationship to antinociception and tolerance. Levels of morphine in brain and other biological materials were measured fluorometrically, and relationships were drawn to tail-flick activity and to tolerance development in rats treated chronically with the narcotic by i.p. infusion. Brain morphine concentration and tail-flick latency both increased with increasing dosage over the first 3 days of the 6-day infusion regimen. There was evidence of cellular tolerance within 24 to 48 hours after the beginning of infusion, with marked tolerance by day 6. Between days 3 and 6 a dispositional tolerance, evidenced by a dramatic fall in brain morphine concentration, also became apparent. After discontinuation of the infusion, the brain morphine dropped to extremely low levels by 24 hours, but significant tolerance to antinociceptive effects remained for 72 hours. Estimation of morphine in plasma, urine, peritoneal tissues and feces suggested several possible explanations for the dispositional tolerance observed. These include increased conjugation of morphine, increased fecal elimination and increased localization in muscle or peritoneal tissues with chronic infusion at relatively high doses. The present work thus examines the pharmacokinetics of morphine in the rat in a chronic treatment model that is currently being used in a number of laboratories for the rapid induction of drug tolerance and dependence.


The development of new iron-chelating drugs. II. For  the past several years, we have searched for an orally effective iron-chelating drug and report here on several compounds which warrant further investigations based on their ability to promote iron excretion in the hypertransfused rat. Administrered orally, 2,3-dihydroxybenzyolglycine induced both urinary and fecal iron excretion, suggesting that a conjugate of 2,3-dihydroxybenzoic acid may be more efficacious than the parent compound. Tropolone, although rather toxic, stimulated fecal excretion of iron when given p.o. at low doses. Evaluation of less toxic derivatives of tropolone appears to be justifiable. L-Histidine may also be of use in chelatin therapy. Fecal iron excretion is significantly increased in response to oral doses of this essential amino acid. Lastly, cholylhydroxamic acid proved to be the most efficacious oral agent examined thus far. A marked increase in fecal iron excretion results from its administration.


An improved assay of 7-ethoxycoumarin O-deethylase activity: induction of hepatic enzyme activity in C57BL/6J and DBA/2J mice by phenobarbital, 3-methylcholanthrene and 2,3,7,8-tetrachlorodibenzo-p-dioxin. An improved in vitro fluorometric assay of the O-deethylation of 7-ethoxycoumarin which is at least 10 times more sensitive than existing methods is described. Nearly quantitative recovery of the product which is essentially free of fluorescent impurities is obtained by a simple two-step extraction procedure. In C57BL/6J mice O-deethylating activity was induced 3-fold by 3-methylcholanthrene and 7-fold by phenobarbital. Administration of phenobarbital resulted in a 10-fold stimulation of enzyme activity in DBA/2J mice. Kinetic analysis indicated that at least two and possibly more components are involved in the metabolism of 7-ethoxycoumarin. Differential stimulation of the maximal activities associated with these components was observed after the administration of phenobarbital, 3-methylcholanthrene, or 2,3,7,8-tetrachlorodibenzo-p-dioxin. The ED50 values for the induction by 2,3,7,8-tetrachlorodibenzo-p-dioxin of 7-ethoxycoumarin O-deethylase and aryl hydrocarbon hydroxylase activities in C57BL/6J mice were almost identical and approximately 10-fold less than in DBA/2J mice similarly treated.


The design of pharmacological experiments using unbiased models of agonist-antagonist interaction. The methods which exist to represent agonist-antagonist interactions, and to distinguish between them are sufficient and effective. Their effective use depends on a set of criteria which are not always fulfilled in actual experiments. In some situations it is difficult or impossible to meet these criteria. An alternative representation is proposed, using straightforward geometry, which evades this problem. It also allows experimental data points to be selected without bias and makes it possible to apply orthodox criteria to more restricted sets of data than is otherwise the case. To do this, it is necessary to reverse the ordinary procedure in antagonist assays, by adding successive concentrations of antagonist to a preparation so that a constant response is evoked by squared multiples of the original agonist dose. This can only be done with rapidly reversible antagonists, but the method has been shown to be effective for such drugs.


Modulation by prostaglandins of the release of acetylcholine and noradrenaline in guinea-pig isolated ileum. The effects of prostaglandin (PG) E2, PGF2alpha and indomethacin on the release of acetylcholine (ACh), noradrenaline (NA) and prostaglandin-like substances from the isolated guinea-pig ileum and its longitudinal muscle-myenteric plexus preparation were investigated. The output of ACh and PGs was determined by a bioassay and the output of NA by an isotope technique. The output of ACh, both resting and stimulated, was decreased by indomethacin (1 micron) especially after a longer exposure. The output of ACh was increased by PGE2 (6 nM) but not by PGF2alpha. This increase was inversely related to the initial level of ACh output; thus, it was marked only in the preparations with low initial output of ACh. Prostaglandin-like substances released from the ileum were mainly of the E type and their output only partially correlated with contractions and with the output of ACh. The stimulated outflow of NA at a frequency of 5 Hz was increased by indomethacin (50 micron) and decreased by PGE2 (30 nM). PGF2alpha had no effect. These results suggest that PGE2 might act physiologically as a modulator of cholinergic transmission whereas its effect on adrenergic transmission could be of a pharmacological nature.


Interactions between digoxin and brief vagal bursts influencing atrioventricular conduction. The interaction between intravenous injections of digoxin (20 microgram/kg every 15 minutes) and brief electrical bursts of vagal stimulation was determined in chloralose-anesthetized dogs. Vagal effect curves were generated to characterize the effect of brief vagal stimulus bursts on atrioventricular conduction. These curves were fit with an analytic expression from which the following parameters were derived as the experimental observations: 1) the maximal change in atrioventricular conduction (deltaPRmax), 2) the time after the stimulus at which atrioventricular conduction was maximally inhibited (Tmax) and 3) the width of the vagal effect curve at one-half the maximal amplitude (TD). Digoxin administration significantly (P less than .05) increased deltaPRmax, Tmax and TD by 21.6 +/- 4.3, 50.0 +/- 16.1 and 125.5 +/- 42.4 msec, respectively, before the disruption of sinus rhythm. Diluent or saline administration did not alter deltaPRmax, Tmax or TD. In addition, digoxin produced dose-dependent increases in deltaPRmax. These results suggest that digoxin vagal interactions not only affect the PR interval but also the time to the maximum delay in atrioventricular conduction and the length of time for depressed conduction after brief bursts of vagal activity.


Mass spectrometric measurement of catecholamine turnover in rat hypothalamus after long-term L-dopa infusion. To test the effect of L-dopa on norepinephrine turnover in rat hypothalamus, we gave steady-state, long-term (19-hour) infusions of L-dopa to conscious, restrained rats. After 19 hours, infusions were switched to identical doses of 2,5,6-trideutero-L-dopa (D3-L-dopa) and production of D3-dopamine and D3-norepinephrine was followed at intervals thereafter. Animals were sacrificed and their hypothalami were dissected and divided into left and right halves. Using gas chromatography-mass spectrometry, we measured isotopic enrichment with one side of the hypothalamus and, after the addition of deuterated internal standards, determined total concentration of dopamine and norepinephrine in the other half of the same hypothalamus. Maximal steady-state enrichment by a given dose of D3-L-dopa was determined by 19-hour infusions of D3-L-dopa alone. Results show that total dopamine production is proportional to dopa dose. Norepinephrine synthesis, on the other hand, proceeds at a constant rate that is independent of dopa dose or dopamine concentration and which is similar to the endogenous rate reported by others using tracer techniques.


The effects of exercise and adrenaline infusion upon the blood levels of propranolol and antipyrine in the horse. There are now several examples showing that experimentally induced changes in hepatic blood flow can have a marked effect upon the elimination of certain high clearance drugs. Changes in hepatic blood flow produced by exercise might therefore be expected to influence the clearance of these drugs. There was an increase of up to 100%, compound to control values, in the plasma levels of propranolol in horses given either d- or dl-propranolol, 0.2 mg/kg b.wt., and then subjected to sustained exercise for 30 minutes. There was, however, no similar increase with exercise in the plasma levels of antipyrine in horses given antipyrine, 50 mg/kg b.wt. Intravenous infusions of adrenaline, 1 microgram/kg b.wt./min for 10 minutes also produced an increase of about 70% in the plasma levels of d-propranolol.


Chemical induction of p-aminohippuric acid transport in renal cortical slices from adult and immature rabbits. Fourteen-day-old and adult rabbits received procaine penicillin G (PEN), 450,000 U/kg s.c., every 12 hours for a total of four doses or phenobarbital-Na (PHB), 40 mg/kg i.p., once daily for 3 days, or 3-methylcholanthrene (3MC), to 20 mg/kg i.p., once daily for 3 days. Twenty-four hours after the final treatment the animals were killed and the kidneys were removed for analysis of enzymatic activities and p-aminohippuric acid (PAH) transport capability. PEN, PHB and 3MC had no effect on PAH transport in slices from adult rabbits but significantly increased PAH transport in slices from 14-day-old rabbits. Aryl hydrocarbon hydroxylase activity was enhanced in both adult and 2-week rabbit kidneys by 3MC while biphenyl-4-hydroxylase activity was enhanced in 2-week and adult rabbit kidneys by PHB. Epoxide hydratase was unaffected by all three treatments. 3MC increased gluthione-S-aryltransferase (ligandin) activity in 2-week but not adult kidneys. Induction of PAH transport in 14-day-old rabbits does not appear to be related to stimulation of microsomal enzymes or glutathione-S-aryltransferase activity in the kidney. Although they are not considered to be substrates for renal organic anion transport, PHB and 3MC resemble PEN in their ability to induce PAH transport in renal cortex of immature but not adult rabbits.


The cardiovascular effects of the antihypertensive drug debrisoquin: a contribution to the pharmacology of chronic treatment. I. One-week administration to dogs. Debrisoquin (5 mg/kg/day) was administered to mongrel dogs on 7 consecutive days either i.v. or p.o. Sixteen hours after the last dose, the animals were anesthetized with chloralose-urethane and subjected to several hemodynamic and biochemical measurements which serve for a comparison with the results of the chronic treatment in a subsequent paper. Aortic blood pressure, cardiac output, heart rate (after vagotomy) and pressor responses to bilateral carotid occlusion were decreased by debrisoquin; cardiac contractility and left ventricular end-diastolic pressure remained unaffected. The fall in vascular resistance of the perfused hind legs which occurred after cutting the lumbar sympathetic chain was smaller after debrisoquin than in controls. Increases in perfusion pressure elicited in the hind legs by electrical stimulation of the peripheral end of the sectioned lumbar sympathetic chain or by i.a. injection of tyramine were inhibited by treatment with debrisoquin. The vascular responses to i.a. injections of norepinephrine, angiotensin and acetylcholine remained unchanged. Isolated perfused mesenteric artery preparations obtained from dogs pretreated with debrisoquin showed reduced pressor responses to periarterial nerve stimulation. Dose-response curves for the pressor effect of norepinephrine were not altered by debrisoquin. Debrisoquin administered i.v. or p.o. depleted to a similar extent the stores of norepinephrine in the heart, spleen, mesenteric and femoral arteries.


Antagonism of the pulmonary vasoconstrictor response to prostaglandin F2alpha by N-dimethylamino substitution of prostaglandin F2alpha. Efforts to develop an in vivo prostaglandin (PG) antagonist have met with limited success. In this study, N-dimethylamino analogs of PGF2alpha which have proven to be effective in vitro prostaglandin antagonists, were tested for antagonism to the PGF2alpha and arachidonic acid (AA) responses in the canine lung lobe preparation. PGF2alpha (1 microgram/kg) and AA (100 microgram/kg) increased lobar arterial pressure by 54 and 83%, respectively. Infusion of analogs did not change lobar arterial pressure. N-dimethylamine PGF2alpha (0.8-3.2 microgram/ml) antagonized the PGF2alpha response by 66 to 79%. N-dimethylamide PGF2alpha (1.6-8.0 microgram/ml) produced a dose-dependent antagonism (24-75%) with an IC50 value of 3.8 microgram/ml. Neither analog significantly attenuated the pulmonary response to AA. Thus, these N-dimethylamino analogs of PGF2alpha exhibit a potency which is superior to previous in vivo prostaglandin antagonists. In addition, they have effectively differentiated the pulmonary vascular responses of AA and PGF2alpha.


Uptake, metabolism and efflux of l-alpha-acetylmethadol (LAAM) by rat lung tissue. The uptake, metabolism and efflux of the longacting narcotic analgesic l-alpha-[2-3H]acetylmethadol ([3H]LAAM) were studied using rat lung tissue slices. Uptake of [3H]LAAM by lung slices incubated in 1 micrometer [3H]LAAM in Krebs-Ringer phosphate buffer was rapid for the first 10 minutes, slow thereafter and reached equilibrium after 30 minutes. Less than 10% of the accumulated radioactivity was found to be in the form of the metabolites noracetylmethadol and methadol. LAAM accumulates in lung tissue primarily by passive diffusion and nonspecific binding. Uptake was against a concentration gradient and could be reduced significantly by iodoacetate or by boiling the tissue and slightly reduced by removing oxygen or Na+ from the medium. However, the uptake process was nonsaturable, was not affected by the removal of Ca++ or glucose from from the medium, lacked stereospecificity and was reversible. Efflux of accumulated [3H]LAAM from lung tissue was a first-order process with an apparent t1/2 of 46 minutes. Many drugs which may possibly be used by patients receiving LAAM, such as methadone, fentanyl, propoxyphene, norpropoxyphene, imipramine, promazine and chlorpromazine, were found to have a significant inhibitory effect on [3H]LAAM uptake and could displace accumulated [3H]LAAM from lung tissue.


Distribution of clozapine in the rat: localization in lung. To determine the distribution of the antipsychotic agent, clozapin (CLZ), a fluorometric procedure for its estimation was devised, and the drug was measured in various tissues of rats after i.p. injection (20 mg/kg). In a 24-hour urine collection, less than 1% injected drug was found. After 1 hour, CLZ concentrations were greatest in lung, spleen, liver and brain (16-64 microgram/g). After 6 hours, CLZ levels in lung remained at 52 microgram/g, whereas concentrations in all other tissues declined to less than 7 microgram/g. When rat lung slices were incubated (O2, 37 degrees C) in CLZ solution (20 microgram/ml), the drug was taken up by the tissue against a concentration gradient, attaining a maximum tissue/medium ratio of 97 after 4 hours. When the concentration of CLZ was raised from 2 to 200 microgram/ml the 1-hour tissue/medium ratio declined from 89 to 21. Chlordiazepoxide, amphetamine and morphine depressed the 1-hour tissue/medium ratio of CLZ by 34 to 50%. CLZ uptake was also decreased 19% by anaerobic conditions and 25% by the presence of 2,4-dinitrophenol. The results suggest that the lung is a site of (active) transport and accumulation for CLZ and perhaps certain other basic drugs.


Hepatic uptake of propranolol.

Hepatic uptake of propranolol. Isolated rat livers were perfused with propranolol and other drugs in a simplified recirculation system without plasma proteins or erythrocytes. The propranolol levels in the reservoir declined biphasically. The first phase was rapid and almost flow-limited despite use of high perfusion flow rates. This rapid uptake generated liver/perfusate ratios greater than 25 and was not significantly diminished by lowering the temperature or removing oxygen from the system. It appeared to reflect one or more physical binding processes. Autoradiography showed high concentrations of propranolol in the periportal zones of the liver lobule. The second, slower phase of uptake was associated with metabolism of propranolol to other compounds and was temperature, oxygen and concentration dependent. A number of drugs inhibited the slow phase but had little effect on the rapid uptake phase. Several of these drugs were able to displace small amounts of propranolol from the liver.


Characterization of SC2644-induced choleresis in the dog. Evidence for canalicular bicarbonate secretion. The biliary clearances of [14C]erythritol (Cery) and [3H]mannitol (Cmann) were measured simultaneously in dogs, first during choleresis induced by varying doses of sodium taurocholate and then by SC2644. Cery increased equally with the increases in bile flow induced by both compounds. Mannitol entry into bile, however, was partially restricted; deltaCmann/deltabile flow averaged 0.66 and 0.68 for taurocholate- and SC2644-induced flows, respectively. These findings suggest a common canalicular site of origin of the increased bile flow. Electrolyte composition was quite different in the increments, however. The bicarbonate concentration in the SC2644-induced increment of bile (65.8 microEq/ml) was three times higher than that associated with bile stimulated by taurocholate. SC2644- and taurocholate-induced biles were virtually isosmotic. These results in concert with other observations suggest a canalicular mechanism for bicarbonate entry into the biliary tree. Stimulation by SC2644 of ductal chloride bicarbonate exchange cannot be excluded, however.


Effects of ethacrynic acid and furosemide on respiration of isolated kidney tubules: the role of ion transport and the source of metabolic energy. In order to investigate the mechanism of action of ethacrynic acid and furosemide, experiments were designed to determine whether these drugs directly inhibit active transport or energy metabolism. The effects of these diuretics on the respiration of tubule suspensions isolated from renal cortex (of rats and rabbits) and outer medulla (of rabbits) were measured. The respiration of tubules prepared from renal outer medulla was stimulated by the presence of chloride in the incubation medium, whereas the respiration of cortical tubules was unaffected by chloride. Both ethacrynic acid and furosemide produced the greatest inhibition of respiration on tubules from outer medulla suspended in chloride-containing media; this result suggests that the diuretics directly inhibit chloride transport. The source of metabolic energy for ion transport was varied by using substrates which donate electrons to the respiratory chain at different phosphorylation sites. Both ethacrynic acid and furosemide inhibit respiration supported by beta-hydroxybutyrate, but there was little or no inhibition of respiration with succinate or tetramethylphenylenediamine ascorbate. Similarly, ouabain inhibited respiration with beta-hydroxybutyrate, but not with the other substrates. Therefore, both diuretics inhibited respiration in a fashion similar to ouabain. It is concluded from both types of experiments that ethacrynic acid and furosemide may directly inhibit active chloride transport.


Modulation of acetylcholine metabolism in the hippocampal cholinergic pathway by intraseptally injected substance P. Intraventricular injection of substance P induced a dose-dependent decrease of acetylcholine (ACh) turnover rate (TRACh) in the hippocampus of rats. The highest dose used (20 nmol) decreased the hippocampal TRACh to 40% of the control value. No changes in the ACh or choline content were detected in the various brain areas 40 minutes after injection, but after 70 minutes an increase in ACh content in diencephalon was significant. Local injection of substance P into the medial nuclei of the septum decreased significantly the hippocampal TRACh. Neither intraventricular injection nor injection into the periaqueductal grey of high doses of substance P (30 nmol) induced analgesia, whereas beta-endorphin (1 nmol) and morphine (15 nmol) were effective. No specific change in the electroencephalograph pattern recorded from either cortex or hippocampus could be detected within the first 2 hours after intraventricular injection of substance P.


Covalent binding of metabolites of acetaminophen to kidney protein and depletion of renal glutathione. Experiments in CD-1 mice and Sprague-Dawley rats were carried out to determine the extent to which biochemical changes described previously for acute acetaminophen-induced hepatotoxicity might be applicable to the kidney. After intraperitoneal injection of acetaminophen, tissue glutathione and covalent binding of tritiated metabolites of acetaminophen to tissue protein were measured for liver, kidney cortex and kidney papilla. Glutathione was reduced more in mice than in rats, and more in liver than in kidney, without appearance of oxidized glutathione in either tissue. Covalent binding was likewise greater in mice than in rats and greater in liver than in kidney. The determination of covalent binding was extremely sensitive to the trace radiochemical impurities of the labeled drug. With prior administration of 3-methyl-cholanthrene, the induced changes were far greater in liver than in kidney, suggesting that the formation of a reactive metabolite from acetaminophen occurred in each organ by slightly different mechanisms. At doses less than those associated with demonstrable acute toxicity, the duration of covalent binding to protein was longer for renal papilla than for renal cortex or for liver. The results may be applicable to the pathogenesis of both acute and chronic nephrotoxicity.


gamma-Glutamyl dopa: a kidney-specific dopamine precursor. gamma-Glutamyl derivatives of amino acids and peptides are selectively accumulated in the kidney and introduced into the metabolism of kidney cells. gamma-Glutamyl L-3,4-dihydroxyphenylalanine (gamma-glutamyl dopa) was synthesized both chemically and enzymatically. Injection of this derivative into mice led to a selective generation of dopamine in the kidney as a consequence of the sequential action of gamma-glutamyl transpeptidase and aromatic L-amino acid decarboxylase, two enzymes which are highly concentrated in the kidney. The concentration of dopamine in the kidney after gamma-glutamyl dopa was almost 5 times higher than that after an equivalent dose of L-dopa. Infusion of 10 nmol/g/30 min of gamma-glutamyl dopa to rats produced a 60% increase in renal plasma flow. By contrast the same dose of L-dopa had no effect on renal plasma flow. Only a small pressor effect was observed after the infusion dose of gamma-glutamyl dopa was increased 20-fold indicating that the systemic effects of this pro-drug slight. The results suggest that the pro-drug gamma-glutamyl dopa can be used as a specific renal vasodilator.


Drug interactions: inhibition of acetaminophen glucuronidation by drugs. Glucuronidation of [3H]acetaminophen (APAP) was studied in rat liver preparations. Both Triton X-100 and UDP-N acetylglucosamine (UDPAG) activated 3- to 4-fold the glucuronidation of APAP by liver homogenates or microsomes. Prednisolone inhibited microsomal glucuronidation of APAP, yielding apparent noncompetitive kinetics in native and in UDPAG-activated microsomes. Studies with UDPAG-activated microsomal preparations show that many drugs can inhibit glucuronidation of APAP markedly; among the most poten inhibitors are: morphine, dicumarol, hydroxyzine, phenolphthalein, chloramphenicol and tetracycline.


The relationship between pharmacokinetics and pharmacodynamic action as applied to in vivo pA2: application to the analgesic effect of morphine. When the pA2 of an antagonist is determined in vivo, administered doses are used rather than the peak or steady-state tissue concentrations. The present report examines the error which can arise in this method and also presents a method for determining the pA2 from data obtained at times after peak. We applied this time-dependent analysis to time-dose-response data obtained with morphine-naloxone in the rat, using tail compression as the nociceptive stimulus. Good agreement between pA2 values was found: 8.0 with peak effect data, and 8.1 with the time-dependent method. Further, this analysis yielded 20 minutes as the half-life of naloxone. It is concluded that the time-dependent method provides a check on the pA2 in vivo and confirms the utility of this constant in classifying receptors. The appendix contains methodology for application to other agonist-antagonist combinations classified according to their kinetics.


Regional and subcellular distribution and some factors in the regulation of reduced pterins in rat brain. We have studied the regional and subcellular distribution, functional role, and pharmacology of quinoid dihydropterin reductase (QDPR) and endogenous reduced pterins (PH4) subserving tyrosin hydroxylase (TOH) and tryptophan hydroxylase in the rat brain. There is a significant correlation between the regional distribution of PH4 and TOH but not between PH4 and tryptophan hydroxylase or between either TOH or tryptophan hydroxylase and QDPR. This suggests that a major portion of PH4 is associated with the biosynthetic activity of brain catecholaminergic systems. The regional and subcellular distribution of QDPR was inconsistent with a regulatory function for QDPR in monoamine synthesis. In vitro measures of PH4, TOH, and synaptosomal dopamine (DA) and serotonin synthesis in the striate cortex of untreated animals and animals subjected to neurotoxin or electrolytic lesions of the dorsal raphe or substantia nigra exhibit significant covariation of PH4 with synaptosomal DA but not serotonin synthesis and a significant partial correlation of PH4 with DA synthesis. The subcellular distribution of PH4 in the striatum demonstrates an association of PH4 with the biosynthetic function of dopaminergic nerve terminals. Reserpine and d-amphetamine in vivo elicited an increase and decrease, respectively, in striatal PH4 paralleling induced changes in synaptosomal DA synthesis. Other drugs altering central catecholaminergic function did not alter striatal PH4 levels significantly. The data suggest that 1) a major portion of total PH4 (as much as 90% in the striatum) is related to the function of catecholaminergic rather than serotonergic systems, 2) PH4 levels is a determinant of the velocity of DA synthesis and 3) PH4 levels are altered by some psychoactive drugs in association with changes in synaptosomal catecholamine biosynthetic rates.


Inhibition of dopamine beta-hydroxylase by 4-hydroxypyrazole: ethanol-pyrazole effects on serum dopamine beta-hydroxylase in vivo. Chronic pyrazole treatment caused a 40% decrease in rat serum dopamine beta-hydroxylase (DBH) activity. Ethanol given simultaneously with pyrazole prevented the inhibition. 4-Hydroxypyrazole, the major metabolite of pyrazole, competitively inhibited both rat serum DBH and partially purified bovine adrenal DBH in vitro. In vivo, 4-hydroxypyrazole caused large decreases in rat serum (53-84%) and adrenal (97%) DBH activity but had no effect on brain enzyme. The decrease in rat serum DBH after chronic pyrazole treatment and the pyrazole-induced changes in physiological parameters, such as body weight and temperature, may be due to the formation of 4-hydroxypyrazole.


Interactions of pyrazole and ethanol on norepinephrine metabolism in rat brain. Single large doses of pyrazole (100-200 mg/kg) given either i.p. or orally caused a decrease in brain norepinephrine and 3-methoxy-4-hydroxyphenylethylene glycol sulfate, but no change in dopamine beta-hydroxylase activity. The effects were enhanced by daily administration for 3 to 4 days. Concomitant administration of ethanol prevented the effects. With smaller doses (50 mg/kg/day) given orally for several days, there was little or no change for 3 days, but after 6 days there was an increase in both parameters. Dopamine beta-hydroxylase activity was also increased. The daily administration of ethanol alone (6.0 g/kg/day) for 6 days caused increased norepinephrine, but 3-methoxy-4-hydroxyphenylene glycol sulfate was diminished and dopamine beta-hydroxylase was unaffected. When the two drugs were given simultaneously, steady-state levels of norepinephrine were unaltered, but the sulfate metabolite was increased as was dopamine beta-hydroxylase. The results suggest that pyrazole and/or ethanol, administered daily for 6 days, leads to adaptive responses in catecholamine metabolism. Pyrazole (or a metabolite) has marked effects of its own, some or all of which are independent of its effects on alcohol dehydrogenase. When the two drugs are administered together, it is difficult to know whether the observed changes are independent or overlapping effects.


Myxosporidan infections in some fishes of Iowa. A survey of 617 specimens of fishes representing 8 families in Iowa revealed coelozoic infections by Chloromyxum catostomi, Chloromyxum triijugum, and Myxidium macrocapsulare and histozoic infections by Henneguya exilis and Myxobolus spp. The trophozoite of M. macrocapsulare is described. Descriptive notes supplementary to previous literature are provided for 3 coelozoic species.


Transmission of salmonid whirling disease by birds fed trout infected with Myxosoma cerebralis. Mallard ducks, Anas platyrhynchos and a black crested night heron, Nycticorax nycticorax were fed trout infected with Myxosoma cerebralis (HOFER) in 2 separate experiments. Feces from the birds were deposited in troughs containing M. cerebralis-free mud as well as in 1 trough without mud. Spore suspensions were also added directly to mud in 1 trough and to another without mud. Susceptible rainbow trout, Salmo gairdneri, developed whirling disease in all troughs containing mud contaminated with M. cerebralis but remained free of infection when exposed to M. cerebralis in troughs without mud. This demonstrates the possibility of bird transmission of the organism causing whirling disease to previously non-contaminated waters.


Method for the simultaneous establishment of many axenic cultures of Paramecium. A method is described for the simultaneous treatment of 42 (or more) stocks of Paramecium, and their adaptation to growth in axenic culture. Samples of dense cultures of these ciliates growing with Enterobacter aerogenes are rendered bacteria-free by migration through 2 sets of tubes containing Adaptation Medium (Peters' salts solution, stigmaterol, vitamins, and autoclaved E. aerogenes). The 2nd set of tubes contains Adaptation Medium plus antibiotics. Bacteria-free samples containing approximately 100 animals are then transferred to test tubes containing Adaptation Medium without antibiotics. This medium also serves as a growth medium. It supports indefinite growth of all Paramecium stocks tested. After adaptation to this medium, the ciliattes can be grown in the axenic medium developed by Soldo, Godoy & van Wagtendonk. On a single trial at least half of the stocks can be expected to produce axenic cultures within 5 to 10 days by these procedures. The method has been applied successfully to several of the species of the Paramecium aurelia complex, to all syngens of Paramecium multimicronucleatum, to several stocks of Paramecium jenningsi, and to 1 stock of Paramecium caudatum and Paramecium calkinsi. A modification of the method also works for Didinium nasutum.


The ribonucleic acids of Crithidia fasciculata. Crithidia fasciculata ribosomes were found to be 80S and to dissociate into 58 and 41S subunits; on 5 to 50% sucrose gradients, rRNA was separated into 25, 18, and 5S components. The molecular sizes of the heavier rRNA species, estimated by polyacrylamide gel electrophoresis were 1.24 and 0.84 M (X 10(6) daltons). The 25S RNA has a tendency to interact with the 18S RNA to give a complex that is difficult to separate by sucrose gradient centrifugation. The 25S RNA is also unstable and dissociates into 0.73 and 0.57 M components. The 18S RNA has molecular size (0.84 M) higher than the 0.7 M reported for most eukaryotes, but similar to that of Euglena and Amoeba. Ribosomal RNA hybridized 0.29% of the nuclear DNA. Mitochondrial RNA, extracted by a rapid procedure was resolved into 16 and 5S components in sucrose gradients.


Effects of methylglyoxal bis(ganylhydrazone) on trypanosomatid flagellates: inhibition of growth and nucleoside incorporation in Trypanosoma brucei. Methyglyoxal bis (guanylhydrazone) (MGBG) at 0.5 mM had little effect in vitro on Blastocrithidia culicis, Crithidia oncopelti, and Leishmania spp., but completely inhibited growth of Trypanosoma brucei. Inhibition became irreversible after a 3-h exposure of T. brucei culture procyclics. Treated organisms remained motile, but failed to divide. Polyamines, spermidine, and spermine, did not reverse the anti-trypanosome action of MGBG (preloading of cells or concurrent administration). Two intraperitoneal injections of the drug at a concentration of 50 mg/kg body weight at a 1-day interval greatly reduced the parasitemia of T. brucei and T. congolense in rats. Trypanosome infections, however, relapsed and killed the animals in 6 days after treatment. It was evident from the results of tracer experiments with T brucei that MGBF significantly lowered incorporation of [3H]thymidine by culture pocyclics and of [3H]uridine by bloodstream forms; in both stages [3H]leucine incorporation was only slightly inhibited. It is suggested that MGBG interferes with nucleoside incorporation by Trypanosoma and that its mode of action is different in bloodstream and culture procyclics.


Coccidian parasites of intertidal fishes from Wales: systematics, development, and cytochemistry. Examination of littoral fish Blennius pholis and Cottus bubalis caught at Aberystwyth and Porth Cwyfan, Wales, U.K. revealed 2 species of coccidia. Eimeria dingleyi sp. n. Oocysts spherical (16.1-19.2) to subspherical (13.9-14.2 X 18.8-20.0) micron, with thin walls; sporulation outside the host to produce ellipsoid sporocysts; endogenous phases in epithelial cells throughout intestine; 26 of 58 B. pholis infected. Eimeria variabilis (Théohan) Reichenow. Oocysts spherical (11.9-14.6) to subspherical (9.2-10.9 X 13.9-14.3) micron, sporulation in lining of pyloric ceca and rectum; previously unrecorded schizonts and gametocytes present; 21 of 25 C. bubalis infected. Electron microscopy revealed that the oocyst wall of E. variabilis consists of a thin membrane whereas the sporocyst wall is thick and 3-layered. Typical oocyst wall-forming bodies were absent from the macrogamete. Cytochemical tests on the endogenous stages of E. dingleyi and E. variabilis indicated that in general they resembled other coccidia in their chemical constitution.


Plasmodium durae Herman from the introduced common peafowl in northern Nigeria. Plasmodium (Giovannolaia) durae Herman was originally described from Kenya, the type host being the common turkey, Meleagris gallopavo Linnaeus. There are no field records of this association outside of Africa, where the parasite, herein reported from another introduced and domesticated bird (the common peafowl, Pavo cristatus Linnaeus), was recently listed from 2 native Phasianidae of the genus Francolinus. The justification for the present identification is submitted against background data concerning malaria parasites from turkeys and other Galliformes in Africa and elsewhere, and restraint is urged in describing yet more "new species" of avian Plasmodium belonging to morphologically close taxa within Novyella and Giovannolaia. A near relative of P. durae, Plasmodium dissanaikei de Jong, is transferred from the former subgenus to the latter one.


Promitosis and rod occurrence in the limax ameba Vahlkampfia lobospinosa. Nuclear division and trophozoite structure and function were investigated in Vahlkampfia lobospinosa. During karyokinesis the nucleolus remained present and divided to form polar masses. Chromatids separated and were directed to the polar masses by spindle fibers within an intact nuclear membrane. No interzonal body was formed. Trophozoites consistently contained and extruded a rod-like structure 10-15 X 1-2 micron. Although it was found in other areas of the cell within the cytoplasm, this rod most frequently protruded from the uroid.


Comparative study of ultrastructure of interlamellar and intralamellar types of Henneguya exilis Kudo from channel catfish. The inter- and intralamellar types of Henneguya exilis Kudo (Myxosporida) infections from channel catfish are similar in spore structure and sporogenesis, but differ in the structure of their plasmodium wall and surface coat and in their relationship with the host cells. The 2 clinical types differ also in the sites of development and growth patterns of plasmodia within a gill filament. Interlamellar plasmodia are limited by 2 outer unit membranes which give rise to both single-and double-membraned pincytic canals. Intralamellar plasmodia are limited by a single outer unit membrane which gives rise to single-membraned pinocytic canals. Interlamellar plasmodia are covered by a fine granular coat of highly variable thicknesses; in some regions there is direct contact between the parasite and cells of the host. There is some evidence that host cell cytoplasm as well as interstitial material are taken in by interlamellar plasmodia. In contrast, intralamellar plasmodia are covered by a fine granular coat of almost uniform thickness, which prevents direct contact between the parasite and cells of the host; probably only interstitial material is taken by these plasmodia.


Development of Eimeria meleagrimitis Tyzzer from sporozoites and merozoites in turkey kidney cell cultures. Sporozoites and 1st-, 2nd-, and 3rd-generation merozoites of Eimeria meleagrimitis were inoculated into primary cultures of turkey kidney cells. In vitro-excysted sporozoites developed into mature macrogamonts in 8 days; in vivo-excysted sporozoites developed into 2nd- or 3rd-generation schizonts within 5 to 7 days. First-generation merozoites obtained from infected turkeys produced mature 2nd-generation schizonts within 24 h. Second-generation merozoites from turkeys produced mature macrogamonts and oocysts within 72 h, whereas 3rd-generation merozoites produced these stages within 48 h. The oocysts that developed from 3rd-generation merozoites sporulated at 25 C and were infective for turkeys. The timing of the early stages and the intervals between schizogonic generations in cultures were comparable with those in turkeys. Morphologic parameters, however, indicated that some differences existed between in vitro and in vivo development. Second- and 3rd-generation schizonts and gamonts that developed after inoculation of cultures with merozoites were similar to stages in turkeys. Oocysts, however, were significantly smaller (P less than 0.05) in cultures. All stages that developed after inoculation of cultures with sporozoites were smaller (P less than 0.05) than their in vivo counter parts.


[Trickling mucography under high pressure and with moderate contrast. First phase of gastroduodenal examinations (author's transl)]. The authors describe a simple and reliable technique of successive mucography of the anterior and posterior surfaces of the stomach. The examination is begun in a seated position, in dorsal horizontal and trickling provides perfect conditions of study, selective and with no opaque superimposition, of the posterior surface of the stomach, the site of 90% of organic lesions. Study of the anterior surface is also simplified. Practically no patient cooperation is required and the technique may be used in the elderly and those with physical incapacity. The aim is to obtain a morphologically and physiologically pure picture of the mucosa and the gastric folds. Very small lesions may be visualised without resort to other techniques and the study of cases of gastritis is greatly simplified.


[Extension of infiltrating cancer of the stomach into the transverse colon (author's transl)]. The extension of infiltrating stomach cancer through the gastrocolic ligament into the transverse colon appears to be relatively common. The radiological appearance is characteristic, with more or less widespread, but shallow, extrinsic prints with irregular contours typical of malignant tumours. Its gastric origin is strongly suggested by its position of the superior border of the transverse colon. The authors report 6 observations in which the value of this very characteristic radiological abnormality of the colon to diagnose primary stomach cancer was confirmed. Radiological appearances are not very specific in primary stomach cancer and interpretation is often difficult; endoscopy or even biopsies are often inconclusive.


[The radiological phenomenon of lumbar vacuum-disc (author's transl)]. Profile films of the lumbar region show the vacuum-disc phenomenon fairly frequently especially at the L5-S1 level and when there is disc degeneration. Two varieties can be distinguished : one with a well-defined enlarged medial image, and a more limited type which is often anterior, at the fibrous ring level and in contact with the vertebral plates. The latter is seen less frequently, but needs to be considered, as it precedes the changes seen in the nucleus pulposus in the intersomatic alteration. It has been shown that this image is of gaseous origin. It is caused by the liberation of gas into a newly-formed intersomatic cavity situated either in the nucleus pulposus or fibrous ring levels. The vacuum-disc phenomenon is of great diagnostic value as it is usually found in relation to degenerated discs and permits orientation of diagnosis towards classical arthrosis or Pott's pseudo-arthrosis when atypical radiological images are seen.


[Early diagnosis of staphylococcic infection in epidural space : radiologic contribution (author's transl)]. Infection of the épidural space was demonstrated on clinic (cauda equina compression) and radiology. Three investigations are considered and compared : Dimer X radiculography, lumbar phlebography, duroliopaque myelography. The transfemoral arcending lumbar catheterization of the epidural veins precise the compression by staphylococcic external pachymeningitis. No liquid is introduced in cerebro spinal fluid : there is not risk of infectious arachnoiditis. Myelography with positive contrast (duroliopaque: ethyl monoiodostearate) is much attractive but it is a procedure not easy to perform,  even badly tolerated by the patient. For these reasons the lumbar phlebography, easily performed, can be realised in first intention.


Analgesics and narcotic antagonists in the benzomorphan and 8-oxamorphinan series. 5. 3-Methoxy-8-oxamorphinans 9 have been prepared from the corresponding 5-allyl-9alpha-hydroxy-2'-methoxy-2-methyl-6,7-benzomorphans 7. The former compounds were transformed to the 3-hydroxy-8-oxamorphinans 6, a class of potent analgesics and analgesic-antagonists. In ring C of the morphinan nucleus substitution of 8-CH2 with oxygen enhanced both analgesic and antagonist activities, while replacement of hydrogen with a methyl group at C-14 in these compounds enhanced antagonist activity and decreased analgesic activity. Tetrahydrofuranobenzomorphans 3 and 3-hydroxy-8-oxaisomorphinans 4 displayed lower levels of activity. Structural requirements for antagonist activity are discussed.


Synthesis and antiinflammatory activity of 6-oxo-1-(beta-D-ribofuranosyl)nocotinic acid and related derivatives. 5-Substituted 1-(beta-D-ribofuranosyl)pyridine-2-ones (6-oxonicotinic acid nucleosides) were prepared by direct glycosylation of 5-ntrio-, 5-carbomethoxy-, 5-carboxamido-, 5-amino, 5-carbobenzyloxyamino-, and 5-acetamido-2-trimethylsilyloxy or corresponding 2-methoxypyridine derivatives by the Hilbert-Johnson method. The glycosylation products were deblocked by conventional procedures and substituents at the 5 position were modified to give the 5-carboxamide, carboxyhydrazide, and carboxylic acid. Only 1-(beta-D-ribofuranosyl)pyridin-2-one-5-carboxylic acid [1-(beta-D-ribofuranosyl)-6-oxonicotinic acid (12), showed significant activity in treating adjuvant-induced arthritis in rats.


Potential antitumor agents. 27. Quantitative structure--antileukemic (L1210) activity relationships for the omega-[4-(9-acridinylamino)phenyl]alkanoic acids. Simple carboxylic acid derivatives of 9-anilinoacridine (e.g., 1,R=-COOH) provide high experimental antileukemic (L1210) activity. The homologous 1'-(CH2)nCOOH congeners also prove active, and there is a parabolic interrelationship between maximum increase in life span in L1210 tests and Rm values used as a measure of agent lipophilic--hydrophilic balance. The corresponding carboxamides [1'-(CH2)nCONH2] provide a similar parabolic relationship, which has an optimum Rm value displaced from that of the acids. Earlier examined 1'-NHSO2(CH2)nCH3 variants, the 3-NHCOCH3 congeners of these, and the carboxamide [1'-(CH2)nCONH2] and sulfonamide [1'-(CH2)nSO2NH2] homologues can be treated as one group and a correlation equation derived that is identical with that for the carboxamide variants alone. The optimum Rm value for this group is displaced from that of the acids by the equivalent of 1.8 log P units on the octanol--water scale. In this drug series a carboxylic acid residue acts as an acceptable hydrophilic unit, providing a log P contribution intermediate between that of the un-ionized acid and the totally ionized carboxylate anion. Quantitative effects of acridine ring substituents on L1210 activity differ in analogues containing either carboxylic acid or alkanesulfonanilde side chains, supporting the view that different site-binding orientations may be involved with these two drug classes.


(Acylaryloxy)acetic acid diuretics. 2. (2-Alkyl-2-aryl-1-oxo-5-indanyloxy)acetic acids. The introduction of an aryl group at the 2 position of the uricosuric diuretics, (1-oxo-2-alkyl-5-indanyloxy)acetic acids, provided compounds with markedly increased potency over their monosubstituted precursors. These compounds were synthesized either by arylation of the corresponding 2-alkyl-5-methoxy-1-indanones with diaryliodonium salts or by alkylation of the 2-aryl-5-methoxy-1-indanones which were cleaved to the corresponding phenols and then converted to the desired oxyacetic acids. Systematic structural variation of the 2-arylindanyloxyacetic acids provided aryl-substituted compounds with varying degrees of uricosuric and diuretic activity.


15,15-Ketals of natural prostaglandins and prostaglandin analogues. Synthesis and biological activities. The synthesis is described of new 15,15-ethylene ketals of natural prostaglandins and prostaglandin analogues. Especially the crystalline trisamine salt of the 15,15-ethylene ketal of 15-dehydro-16-phenoxy-17,18,19,20-tetranorprostaglandin F2alpha is a very active inducer of luteolysis in laboratory animals and cattle.


Inactivation of trypsin-like proteases by sulfonylation. Variation of positively charged group and inhibitor length. Attempts to achieve selective inactivation of serine proteases of closely related specificity (trypsin-like) by aryl sulfonylation have been extended. Nitrophenyl esters of benzenesulfonic acid and phenylmethanesulfonic acid containing various positively charged groups have been synthesized and examined as inactivators of trypsin, thrombin, plasmin, plasma kallikrein, and urokinase. Examples of selective inactivation by isothiouronium derivatives were found and attributed to differences among these enzymes in geometry and flexibility of the primary specificity sites.


3-Aryl- and 3-hydroxy-3-aryloctahydropyrido[2,1-c][1,4]oxazines. Synthesis, stereochemistry, and central nervous system pharmacological actions. A series of substituted 3-aryl- and hydroxy-3-aryloctahydropyrido[2,1-c][1,4]oxazines has been synthesized for purposes of investigating potentially useful CNS pharmacological actions of this novel heterocyclic system. The preferred conformation of the bicyclic system of the parent compounds, 1 and 2, has been shown to be trans with equatorial orientation of the 3-phenyl substituent in each compound. The various substituted aryl analogues of this series are depressants of motor activity in mice, and certain analogues exhibit significant anticonvulsant and appetite suppressant activity in test animals.


A Fujita--Ban structure--activity analysis of 44 steroids. A Fujita--Ban structure--activity analysis has been performed on 44 steroids with a common pregn-4-ene-3,20-dione structure. The measured biological activity was glycogen deposition in the liver, expressed relative to the activity of cortisol. Substituents are at positions 2, 6, 9alpha, 11beta, 16alpha, 17, and 21. Substituents of positions 2, 6, and 17 accounted for 60% of the total variance. The substituents with significance at the p less than 0.01 level were 6alpha-hydrogen, 6alpha-methyl, 2alpha-hydrogen, 9alpha-fluorine, and 9alpha-hydrogen.


Molecular structure of 1-(2-chloroethyl)-3-(trans-4-methylcyclohexyl)-1-nitrosourea. The three-dimensional structure  of  1-(2-chloroethyl)-3-(trans-4-methylcyclohexyl)-1-nitrosourea (MeCCNU, NSC-95441), an effective antitumor agent, has been determined by single-crystal x-ray diffraction. MeCCNU crystallizes in monoclinic space group P21/c, with  cell dimensions  a =  12.387, b  =  10.810, and  c  =  10 .198  A , beta  =  102.62  degrees , and  Z  =  four  molecules  per  unit  cell. The structure was solved by direct phasing procedures and refinement by anisotropic least squares converged at a discrepancy index R = 0.065. The cyclohexyl ring is in the chair conformation with the plane of the nitrosourea moiety twisted approximately 90 degrees from the cyclohexyl ring. The carbon-nitrogen bonds of the urea group are significantly asymmetric.


Benzomorphans. Structure of a position isomer. May's benzomorphan synthesis leads not only to the alpha or cis isomer and the beta or trans isomer but also to a position isomer hereinafter called the gamma isomer. The structure and synthesis of this isomer are described. Biological activities of the alpha and gamma isomers are compared.


Synthesis and analgesic activity of some long-acting piperidinospiro derivatives of methadone. A congener of methadone, in which the metabolically labile C-6 dimethylamino moiety was replaced with a piperidinospiro derivative, was reduced and acetylated. This conversion produced a marked increase in the duration of analgesia, a trend similar to that found for methadone.


Antiallergic 9-oxo-11-hydroxy-5H,9H-[2]benzopyrano[4,3-g][1]benzopyrans. The synthesis and properties of the title compounds 1 are described. Several of these compounds, in addition to being potent inhibitors of the passive cutaneous anaphylaxis reaction of rats against egg albumin challenge, significantly block the effects of several mediators of anaphylaxis in isolated smooth muscle preparations. An improved procedure for the isolation and partial purification of SRS-A from chopped guinea pig lung tissue is also described.


Synthesis and antibacterial activity of isomeric 6- and 7-acetyl-3-methyl-2- quinoxalinecarbozamide 1,4-dioxides. The synthesis, separation, and structure determination of 6- and 7-acetyl--3-methyl-2-quinoxalinecarboxamide 1,4-dioxides are reported together with a comparison of their antibacterial activity. The structural assignment of these 6- and7-acetyl isomers was based on NMR analysis of related mono-N-oxide derivatives, which were obtained by treatment of the quinoxaline 1,4-dioxides with acetic anhydride--acetic acid or trimethyl phosphite. The compounds were screened for in vitro and in vivo activity against Escherichia coli, Salmonella choleraesuis, Pasteurella multocida, and Streptococcus pyogenes. Although the isomers were found to possess similar activity, the 7-acetyl isomer was more active therapeutically in mice than the 6-acetyl isomer when administered parenterally.


Quinolone antimicrobial agents. 1. Versatile new synthesis of 1-alkyl-1,4-dihydro-4-oxo-3-quinolinecarboxylic acids. A flexible reaction sequence has been developed which starts with readily available anthranilic acids or isatoic anhydrides and leads regiospecifically to 1-alkyl-1,4-dihydro-4-oxo-3-quinolinecarboxylic acids after reaction with 1,3-dicarbonyl compounds. The sequence is superior to earlier published methods by allowing electron-releasing and -withdrawing groups in any position on the aro;atic ring, by allowing convenient substitution at C2, and better overall yield. A number of new and known antimicrobial agents were prepared and tested in vitro, demonstrating, inter alia, that substitution of the H at C2 abolished antibacterial activity.


Synthesis and hypoglycemic activity of some substituted 2-arylthiazolo[3,2-a]pyridinium salts. A series of substituted 2-arylthiazolo[3,2-a]pyridinium salts (1a-q) was prepared by known methods and tested for hypoglycemic activity in 48-h fasted rats. Two compounds, 2-phenylthiazolo- and 8-methyl-2-phenythiazolo[3,2-a]pyridinium perchlorate (1a and 1q), showed consistent hypoglycemic activity in this screen, demonstrating that a high degree of structural specificity was required for hypoglycemic activity. At higher doses the hypoglycemic activity of 1a and 1q was associated with elevated levels of hepatic triglycerides.


Improvement of teaching skills in a clinical setting. The article describes the efforts of the faculty members in the Department of Community Medicine at the Rockford School of Medicine to improve their clinical teaching skills in the Primary Care Experience (formerly the Basic Ambulatory Experience). Faculty members opted for an instructional development program under the direction of an educational consultant as a result of their problems with clinical teaching in a new medical school. Each faculty member's teaching was videotaped and analyzed by the consultant, who met with the instructor to discuss the videotape, From this initial discussion problem areas were defined to be discussed at large group meetings. Faculty members will be videotaped in the present academic year to ascertain improvement in their clinical teaching.


Educational costs to hospitalized patients. One of the less obvious costs of educational programs is the increased volume of work-ups and treatment for hospitalized patients that are ordered by residents. In a hospital which has both private teaching and private nonteaching floors, a comparison of these costs shows that service charges on teaching floors are 60 percent higher than on nonteaching floors. The sicker the patients are, the greater is the disparity.


Planning student work-study time in an objectives-based medical curriculum. By developing, validating, and using a formula for predicting students' time commitment to their studies, those responsible for developing curricula can make their planning more precise. Overloads and underloads can be identified a priori, competition between concurrent courses can be reduced, and changes in course content and structure can be based on empirical data. The formula should be useful at all undergraduate levels and with a variety of educational formats.


A student's perspective on community medicine and the health crisis. Community medicine is more difficult to teach and to learn than the traditional medical sciences. Teachers of community health have an interest in the rigors and theory of epidemiology and biostatistics, while most students plan a career in patient care. Abstractions and statistical data need not be presented unless it can be shown that these are the "physical findings" of a community and that they have value in the discovery of the etiology of disease, the prediction of risks, and the delivery of health care. Community medicine curricula must include experiential learning, with real patients and problems, in order to prove that health is affected by culture, politics, the environment, and individual behavior. If a student-physician's concern for community health is to be enduring, it must match in sophistication his skill in clinical medicine.


Introducing first-year medical students to early diagnostic hypotheses. The early formation of hypotheses is recognized as an important part of a clinical diagnosis (clinical problem-solving). This paper describes a method of instruction in gynecology for first-year medical students which encouraged the formulation of early diagnostic hypotheses. In paper and pencil case simulations designed for independent learning, students were provided with a set of clinical clues that helped them make broad general diagnostic hypotheses rather than the narrow hypotheses typical of beginning students. A description of the method of evaluating the student's ability to form diagnostic hypotheses, the results of evaluations, and the students' perceptions of the course are included in this report.


The core course in medical microbiology at Baylor College of Medicine. During the past five years at Baylor College of Medicine student performance in microbiology, as measured by scores on the examination of the National Board of Medical Examiners, has improved from less (mean of 78 percent) than the national average of 80+ percent to considerably greater than the national average (mean of 85 percent). Only about one-half the time usually given to microbiology is allotted to the course at Baylor (107 hours). Principal features of the course are annually revised lecture handouts, medically oriented laboratory sessions with a manual written especially for the course, and clinical demonstrations of infectious disease. The pattern of performance in the microbiology course did not occur in two other basic science courses at Baylor. The improvement in performance appeared to be related to the course format, increased teaching proficiency, and the allocation of hours to the various subdisciplines.


Structural factors as determinants of career patterns in medicine. This study was concerned with the role of structural factors in influencing medical career outcomes. These factors were viewed as an interrelated network of institutions, linked in particular patterns, leading to alternative career outcomes. A conceptual model was developed to represent the expected, predominant routes to different career outcomes. Analysis of data gleaned from the Association of American Medical College's Longitudinal Study revealed neither the expected patterns nor distinctive, alternative patterns. Thus, the notion that medical education is a rigidly structured system, consisting of a few, relatively fixed patterns leading to different career outcomes, was not supported. However, further analysis indicated evidence of stratification among structural factors in the medical education system which serves to influence access to career pathways.


A systems intervention for improving medical-school-hospital interrelationships. The large number of affiliations between medical schools and hospitals resulting from recently increased size of schools has typically been accompanied by both school-hospital and hospital-hospital interrelationship problems involving faculty and administrative personnel in all departments and at all levels. In this paper the authors describe a new technique, "systems intervention," designed specifically to deal with problems of needed change in complex organizational settings, and they illustrate its use by reporting a case study of the relationships between Tufts University School of Medicine and its associated hospitals. The process combines system analysis and behavioral science techniques to promote understanding and overcome barriers to change. Changes attributed to the systems intervention at Tufts are outlined.


The SIU medical curriculum: systemwide objectives-based instruction. The Southern Illinois University School of Medicine has completed a five-year experience applying an objectives-based approach to an entire curriculum in a medical school setting. Approximately 250 students have worked and studied within the system, and three classes have been graduated. This paper describes the instructional system and the procedures for monitoring, maintaining, and improving it and provides available outcome data.


Comparing medical audits: correlation, scaling, and sensitivity. A modified Payne process and the JCAH intermediate outcome medical audits were applied to 6,980 cases in eight diagnostic categories within 22 hospitals, representing 1,321 attending physicians. Overall correlations between the two audits differed substantially from diagnosis to diagnosis, allowing for generally inconsistent and conflicting results when applied to a specific research question. Methods are illustrated for comparing the relative scaling (harshness) and sensitivity (discriminating power) of these two audit methods. The effects of the specificity of items, total number of items, outcome versus process indicators, and weights of items on the measurement characteristics of the audit methods are also discussed.


Using a competency-based program to assess interviewing skills of pediatric house staff. A program has been initiated to assess objectively the interviewing skills of pediatric house staff. Each entering house staff member interviews and is evaluated by a nonphysician mother who presents the medical history of her child. Remedial instruction is provided for all who do not perform in accordance with established minimum criteria. As a result of this competency-based program, all house staff members are now known to have attained at least a minimum level of competence in interviewing technique.


A model for teaching early child development. A model of teaching psychological aspects of infant growth and development to medical students in a pediatric clinical rotation is described. Small groups of 8 to 10 medical students observe an infant developmental-assessment-parent-interview conducted by a child development specialist. Emphasis is placed upon demonstrating infant temperament, age-appropriate competencies, and the dynamic interplay between parent and child. Evaluation of this training program suggests its effectiveness as a method of instruction and its usefulness as an approach to the evaluation of the young child.


A study of carbon dioxide-dependent strains of Streptococcus milleri. Forty-four strains of non-haemolytic streptococci, from a variety of sites, that required CO2 for aerobic growth were identified as Streptococcus milleri. Of these strains, 40 (90%) possessed the Lancefield group-F antigen, the remainder being non-groupable with antisera to the group antigens A, C, F and G.


Effects of cephalexin, erythromycin and clindamycin on the aerobic Gram-negative faecal flora in man. The effects of 5-day courses of orally administered cephalexin, clindamycin and erythromycin on the Gram-negative, aerobic faecal flora of healthy adults were examined. The concentration of cephalexin reached in the intestine was high enough to cause the emergence of resistant Gram-negative bacteria; organisms belonging to the genera Enterobacter, Citrobacter and Pseudomonas increased to easily detectable levels. The faecal concentration of erythromycin was high and caused a severe reduction of the coliform flora. Clindamycin administration resulted in a considerable increase in the coliform count; the increase in the proportion of klebsiellae was especially marked.