(-)-2-Hydroxy-n-cyclopropylmethylmorphinan: radioimmunoassay and phamacokinetic profile

The pharmacokinetic profile of (-)-2-hydroxy-N-cyclopropylmethylmorphinan (HCMM), a narcotic antagonist and analgesic, has been evaluated in man following administration of 25 to 50 mg of the drug orally and 10 to 15 mg intramuscularly. A specific radioimmunoassay procedure was developed for the determination of HCMM in plasma and urine. The drug had a mean "apparent" elimination half-life in plasma of about 11 hr following both routes of administration. A mean of 47% of the oral dose was excreted in the urine as unconjugated and conjugated HCMM and only 5% of the dose was excreted as intact HCMM. In one subject studied, the plasma levels of conjugated HCMM were as much as 5-fold higher than the levels of unconjugated drug. Although there was considerable intersubject variability following both routes of administration, the overall pharmacokinetic parameters suggest that oral and intramuscular doses are bioequivalent.

Gram-negative endocarditis caused by Campylobacter fetus

Campylobacter fetus is a rare cause of endocarditis that is difficult to diagnose because of the fastidiousness of the organism. The source of infection is unknown and it may involve a normal or previously damaged aortic valve. The onset is insidious, and if there is a prior history of recent onset of fever, thrombophlebitis, and diarrhea, infection caused by this organism should be considered. Echocardiography may be useful. The organism is sensitive to a variety of antibiotics, including the combination of penicillin and streptomycin. The prognosis and survival are good.

The Aymara of Western Bolivia. IV. Gene frequencies for eight blood groups and 19 protein and erythrocyte enzyme systems

A total of 315 individuals, mainly of Aymara origin, from western Bolivia were examined for genetic variation at eight red cell antigen and 19 serum protein and red cell enzyme loci. The gene frequencies for polymorphic loci and the discovery of several rare variants are discussed in terms of previous work among the Aymara and the closely related Quechua. The effect of inclusion of related individuals in the sample on gene frequency, variance of gene frequency and genetic distance, is discussed.

Initiation and termination of deoxyribonucleic acid replication in bacteria after a stepwise increase in the velocity of replication

The theoretical relations between replication, initiation, termination, and deoxyribonucleic acid (DNA) accumulation were derived for experiments in which the length of the time required for the replication of the bacterial chromosome (C period) can be varied. This theory enables one to determine absolute values of the C period from kinetics of DNA accumulation after a "stepup" with thymine-requiring bacteria that are subjected to a sudden increase in the exogenous thymine concentration. Application of this method of data evaluation to an observed step-up experiment with a thy-derivative of Escherichia coli B/r (ATCC 12407) indicated that the theory describes the observed post-step accumulation of DNA accurately within experimental errors. It is also concluded that changes in the replication velocity (C) do not measurably affect the timing of initiation events in a culture.

Role of ribosomal protein S12 in peptide chain elongation: analysis of pleiotropic, streptomycin-resistant mutants of Escherichia coli

Some of the spontaneous streptomycin-resistant mutants of Escherichia coli strain C600 exhibit pleiotropic effects in addition to the antibiotic resistance. These effects include decreased growth rates, reduced levels of certain enzymes, and poor support of bacteriophage growth. One of these mutants, strain SM3, was studied further. We have examined the question of whether the reduced growth rate of the mutant SM3 is related to the reduction in relative amounts of ribosomes or to the reduction in the efficiency of ribosomes in protein synthesis. Measurements of alpha, the differential synthesis rate of ribosomal protein, revealed that the protein synthesis effeciency of ribosomes from the mutant strain SM3 was reduced about twofold relative to that of the parent strain C600. Measurements of the induction lag for beta-galactosidase and of the synthesis time of several different molecular-weight classes of proteins indicated that the mutation resulted in a marked reduction in the peptide chain growth rate. This reduction in the chain growth rate probably accounted for most of the observed reduction in the growth rate of the mutant strain. These experimental results show that the strA gene product, the S12 protein of the 30S subunit, is involved in some aspect of protein chain elongation. Presumably this involvement occurs during the messenger ribonucleic acid-directed binding of transfer ribonucleic acid to the ribosome.

Effects of subcutaneously implanted sustained-release cyclophosphamide capsules on Walker 256 solid rat tumor

Complete regression of Walker 256 solid rat tumor was brought about by the subcutaneous implantation of a single sustained-release cyclophosphamide capsule adjacent to the tumor mass. Untreated control animals died within 3 weeks after receiving the tumor with large necrotic masses. Rats with sustained-release capsules experienced complete tumor regression within 28 days. Upon examination, the tissues around the previous tumor mass has regenerated, and no viable tumor cells could be found in the area where the previous tumor mass was. Around the implanted sustained-release cyclophosphamide capsule a fibrous sheath has developed over the 3 weeks it was in situ. This study suggests an alternate means of cytoxic drug administration in the treatment of solid tumors in experimental animals.

Polypeptide-chain-elongation rate in Escherichia coli B/r as a function of growth rate

By evaluating the kinetics of radioactive labelling of nascent and finished polypeptides, the peptide-chain elongation rate for Escherichia coli B/r at three different growth rates (mu) was determined to be 17 amino acids/s for the fast-growing cells (mu equals 1.3 and 2.0 doublings/h) and 12 amino acids/s for slow-growing cells (mu equals 0.67 doublings/h). The results agree with the growth-rate-dependence of the rate of peptide-chain elongation found for the translation of newly induced beta-galactosidase messenger in this strain and under these conditions of growth [Dalbow & Young (1975) Biochem. J. 150, 13-20]. Together with the previously observed ribosome efficiency at these growth rates [Dennis & Bremer (1974) J. Mol. Biol. 84, 407-422] the results indicate that the fraction of ribosomes engaged in protein synthesis is about 0.8 at all three growth rates.

Balanced production of 30S and 50S ribosomal proteins after a nutritional shift-up

The synthesis of bulk ribosomal protein (r-protein) after a nutritional shift-up in Escherichia coli B/r was examined. It was found that the molar ratio of the net synthesis rates of 30S and 50S r-protein remains constant during the transition period after the shift-up and equal to the preshift ratio. The implications for the control of ribosome synthesis are discussed.

Analysis of enzyme induction in bacteria

The theoretical relations between the induced initiation and accumulation of lac mRNA and its translation are derived, taking the kinetics of repressor-operator dissociation and enzyme maturation into account. These relations are used to evaluate observed data on lac induction and to estimate a number of parameters that characterize the transcription and translation of the beta-galactosidase gene in the bacterium Escherichia coli B/r growing at three different rates (0.7-2.1 doublings/h).

Synthesis time of beta-galactosidase in Escherichia coli B/r as a function of growth rate

By analysing the kinetics of beta-galactosidase accumulation after induction, the synthesis time of beta-galactosidase in Escherichia coli B/r was found to be 75s in rapidly growing cells (1.36 and 2.1 doublings/h), and 90s in slowly growing cells (0.63 doubling/h). These values correspond to peptide-chain-elongation rates of 16 and 13 amino acids/s respectively, in agreement with previous findings, indicating that the peptide-chain growth rate is constant (presumably maximal) in fast-growing bacteria, but decreased in slowly growing bacteria [Forchhammer & Lindahl (1971) J. Mol. Biol. 55, 563-568].

Deanol and methylphenidate in minimal brain dysfunction

Deanol, a putative acetylcholine precursor, has been used as a treatment for childhood hyperactivity for years. Efficacy has not been satisfactorily established, however. Seventy-four children referred for problems with learning, including many with hyperactivity, were screened for neurological or psychiatric illness, then given deanol, methylphenidate, or placebo in a double-blind fashion for 3 months. Maintenance dose for methylphenidate was 40 mg daily; for deanol, 500 mg. Behavior rating forms, reaction time, and a series of standard psychometric tests were given before and after treatment. Both drugs showed significant improvement on a number of tests; the pattern and degree of change differed slightly for the two. In this paradigm, deanol thus appeared to improve performance in children with learning and behavior disorders. The mechanism of action remains speculative; proof that deanol increases acetylcholine is scanty, and there is a theoretical basis for actually assuming an anticholinergic effect. Further clinical studies on deanol are indicated.

Effect of progesterone on estrogen receptors in the rabbit uterus

The macromolecular binding of estradiol was investigated in the rabbit uterus under various hormonal states in a search for evidence of progesterone antagonism of the estrogen-receptor complex interaction. Progesterone did not alter the sucrose gradient sedimentation characteristics of the estrogen-receptor complex in estrus or castrate animals. Progesterone treatment of castrated animals did not alter the absolute number of EBS (estrogen-binding sites) per cell, but did result in decreased relative concentration of EBS by increasing the soluble protein content of the cells over that seen in untreated castrates. Castration did not alter the absolute number of EBS per cell but did increase the relative concentration of estrogen binding in the cytosol.

Treatment of thyrotoxicosis during pregnancy with propranolol

The treatment of two pregnant thyrotoxic patients with propranolol alone is discussed. One patient had a spontaneous remission during pregnancy wile taking propranolol. In the other patient treatment with propranolol allowed postponement of definitive therapy until after delivery, when the fetus was no longer at risk. There were no complications of therapy in either patient and both infants were normal. The use of propranolol in thyrotoxicosis is discussed and the pertinent literature is reviewed. Regional anesthesia is preferred over general anesthsia in patients taking propranolol. Patients taking propranolol who require general anesthesia for delivery should have continuous monitoring of electrocardiogram and central venous pressure. To this date no method of therapy has been free of fetal side effects. Surgical treatment is associated with occasional abortion or premature labor; antithyroid medication occasionally results in fetal goiter or cretinism.

Epidemic Venezuelan equine encephalitis in North America in 1971: vector studies

A major epidemic of Venezuelan equine encephalitis occurred in south Texas in the summer of 1971. More than 1500 equines died of VEE in Texas, and 110 human cases with no deaths were reported. Vector studies in south Texas and northern Tamaulipas revealed that the overall mosquito infection rates during the peak of the epidemic were about 1:100, one of the highest rates observed for a major epidemic. Mosquito infection rates of this magnitude could easily explain the intensity of VEE outbreaks in both equines and man. A total of 943 VEE virus isolations were made from mosquitoes. Eight of the 12 mosquito species found infected were implicated in the epidemic cycle of VEE for the first time. Sufficient laboratory and field evidence is available to prove that Psorophora confinnis was one of the primary vectors of VEE. The lack of laboratory evidence necessitates the use of the term "probable" primary vectors for other species apparently equally as involved on the basis of field infections; these include Aedes sollicitans, Aedes thelcter and Psorophora discolor. Eight other species from which less than 10 VEE virus isolations were made were considered auxiliary vectors. Mosquitoes of some species were tested individually; such tests showed 2-4% of the probable primary vectors to be infected. The first isolation of VEE virus of the epidemic was made from P. confinnis on June 28, 1971. Highest mosquito infection rates occurred during the week of July 5. Mosquito infection rates declined precipitously in the last 3 weeks of July 1971, signaling the end of the epidemic in the study area. One explanation for the decline was that equines, the principal epidemic hosts, were eliminated as a source of virus by death or by acquisition of natural or induced immunity. Mosquito control appeared to be effective in reducing the infected mosquito population while the immunization of equines with TC 83 VEE vaccine was accomplished. Quarantines appeared to be effective in restricting the VEE virus activity to south Texas. Undoubtedly all of the control measures contributed to stopping the epidemic. Continued VEE surveillance by various government and other agencies failed to reveal any further epidemic VEE activity in the US in 1972. Other arboviruses isolated during the VEE studies in south Texas included St. Louis encephalitis virus, and San Angelo subtype of the California Group. A virus of the Bunyamwera Group was also isolated from Palo Blanco, Tamaulipas.

Breast tumor cell lines from pleural effusions

During 1973, 4 new epithelial tumor cell lines were isolated from pleural effusions from breast cancer patients. We describe 3 of these lines: MDA-MB-134, with a mean chromosome number of 43; MDA-MB-175, with a mean chromosome number of 49; and MDA-MB-231, with a mean chromosome number between 65 and 69. We isolated the same cell type from 4 of 10 effusions from MDA-MB-134 and from 6 of 8 effusions from MDA-MB-175. We found that pleural effusions as a source of breast tumor cells to be cultured and studied in vitro have the following advantages: 1) large amounts of material and the possibility of obtaining sequential samples from the same patient; 2) high viability of tumor cells; 3) scarcity or absence of fibroblasts; and 4) the possibility of separating the tumor cells from other “contaminating” cell types by differences in their speed or degree of attachment to the flask. All lines from different patients differed, as seen grossly and microscopically. All lines from sequential pleural effusions from the same patient were apparently alike. No viruses or mycoplasmas were detected in any line.

Simple quantitative vectorcardiographic criteria for the diagnosis of right ventricular hypertrophy

The vectorcardiogram is a useful supplement to the conventional electrocardiogram in the recognition of right ventricular hypertrophy. Many quantitative criteria have been proposed. However they are often too complicated for routine clinical application. Based on the distribution of the QRS loop area in the various quadrants in the vectorcardiogram in 198 normal subjects, three simple criteria for diagnosis of right ventricular hypertrophy are derived: 1) the anterior and rightward QRS loop area in the transverse plane is greater than 70% of the total; 2) the QRS loop area in the right posterior quadrant of the transverse plane is greater than 20% of the total; 3) the QRS loop area in the right inferior quadrant in the frontal plane is greater than 20% of the total. Vectorcardiogram recordings in 97 patients with atrial septal defect, mitral stenosis, and chronic obstructive lung disease with pulmonary hypertension met one or more of the criteria in 80 (83%). The conventional electrocardiogram of these patients was suggestive of right ventricular hypertrophy in 64 (66%). It is concluded that the proposed vectorcardiographic criteria provide a sensitive means for the diagnosis of right ventricular hypertrophy. Their specificity however was not tested.

Effect of exposure to subfreezing temperatures on ethylene evolution and leaf abscission in citrus

Citrus leaves exposed to subfreezing temperatures evolved ethylene at rates between 0.1 and 38.3 microliters per kilogram fresh weight per hour whereas untreated leaves evolved between 0.01 and 0.50 microliter per kilogram fresh weight per hour. Leaves not injured by freezing temperatures did not abscise, and ethylene evolution was near normal after 2 days. Freeze-injured leaves continued evolving high ethylene levels 4 or 5 days subsequent to freeze injury, and many of the freeze-killed leaves abscised. Supportive evidence suggested freeze-induced ethylene was involved in freeze-induced leaf abscission; whereas freeze-inhibited abscission was not due to a lack of ethylene but injury to other metabolic systems necessary for abscission.