Survival after prolonged persistent pulmonary hypertension.

We report an infant with prolonged persistent pulmonary hypertension (PPH) who failed to respond to various mechanical and pharmacological therapies but who showed spontaneous improvement at 13 days of age. We therefore stress that assisted ventilation should be continued in PPH without major structural cardiac or pulmonary abnormality or ongoing iatrogenic complications, as recovery may occur at any time.

Comparison of the vacuolar membrane ATPase of Neurospora crassa with the mitochondrial and plasma membrane ATPases.

The vacuolar membrane ATPase of Neurospora crassa closely resembles the mitochondrial ATPase in its substrate specificity, substrate affinity, and sensitivity to the inhibitor N,N'-dicyclohexylcarbodiimide. Three different mutants with altered mitochondrial ATPase activity, exhibited as 1) resistance to N,N'-dicyclohexylcarbodiimide, 2) enhanced sensitivity to N,N'-dicyclohexylcarbodiimide, and 3) very low specific activity, were found to be unaltered in the vacuolar membrane ATPase. The vacuolar membrane ATPase was similar to the mitochondrial ATPase and approximately 10-fold more sensitive than the plasma membrane ATPase in its sensitivity to the inhibitors 7-chloro-4-nitrobenzo-2-oxa-1,3-diazole, 2',3'-O-(2,4,6-trinitrophenyl) adenosine 5'-triphosphate, and 5'-adenylylimidodiphosphate.

Day patient versus in-patient: factors determining selection of acutely ill patients for hospital treatment.

In a prospective study the criteria and characteristics associated with the admission of acutely ill psychiatric patients to in-patient or day hospital care were examined. Over a four-month period, 54 patients were admitted to hospital and 43 to a day hospital. There was significantly more schizophrenics in the hospital.

The appearance of endogenous opiates in cerebrospinal fluid following opiate injection in various animal species.

Phenylquinone writhing, tail-flick, stimulated guinea pig ileum and mouse vas deferens were used to quantitate opiate-like activity in CSF taken prior to and at various times after the injection of morphine. The injection of various doses of morphine caused a dose responsive increase in opiate-like material in rabbit CSF taken at the peak of activity (60 min later). Morphine also caused an increase in opiate activity in dog CSF.

Identification and properties of an ATPase in vacuolar membranes of Neurospora crassa.

Using a vacuolar preparation virtually free of contamination by other organelles, we isolated vacuolar membranes and demonstrated that they contain an ATPase. Sucrose density gradient profiles of vacuolar membranes show a single peak of ATPase activity at a density of 1.11 g/cm3.

Isolation and characterization of plasma membranes from wild type Neurospora crassa.

A method has been developed to isolate plasma membranes with high ATPase activity from wild type Neurospora. Cells are treated with snail enzyme to weaken their cell walls, disrupted by gentle homogenization in a medium designed to keep mitochondria and other organelles intact, and fractionated by differential centrifugation. After removal of mitochondria, several higher speed particulate fractions (particularly one sedimenting at 40,000 X g) contain an ATPase that can be identified as the plasma membrane enzyme on the basis of sensitivity to vanadate and kinetic properties.

Synthesis and preliminary binding studies of 4,4-ditritio-(-)-nicotine of high specific activity.

4,4-Ditritio-(-)-nicotine (5) of high specific activity (4.7 Ci/mmol) has been synthesized from (-)-nicotine via the readily prepared 4,4-dibromocotinine (3). Scatchard analysis of the binding of 5 to the crude mitochondrial fraction of whole rat brain revealed a Ka of 4.

Identification of ribonuclease P activity from chick embryos.

RNAase P (EC 3.1.26.

Nicotine antibodies: comparison of ligand specificities of antibodies produced against two nicotine conjugates.

Conjugates between bovine serum albumin and (R,S)-2-aminonicotine were produced, and these conjugates were employed in rabbits and goats for the production of nicotine antibodies. In the assay of nicotine, an 125I-tyrosine methyl ester derivative of (R,S)-6-aminonicotine was employed as radioligand. The antibody-bound derivative was separated from the free derivative by charcoal adsorption (0.

Automated radioimmunoassay of nicotine.

We have developed an automated nonequilibrium procedure for the radioimmunoassay of nicotine. The use of a unique iodinated nicotine derivative in this procedure gave a sensitivity of 10 micrograms/l for nicotine with a between-run precision of 7.4% and within-run precision of 6.

Ribonuclease P: an enzyme with an essential RNA component.

The activity of ribonuclease P on precursor tRNA substrates from Escherichia coli can be abolished by pretreatment of this enzyme with micrococcal nuclease or pancreatic ribonuclease A, as well as by proteases and by thermal denaturation. Highly purified RNase P exhibits one prominent RNA and one prominent polypeptide component when examined in polyacrylamide gels containing sodium dodecyl sulfate. The buoyant density in CsCl of RNase P, 1.

The interrelationship between the metabolism of (S)-continine-N-oxide and (S)-cotinine.

The metabolism of (S)-cotinine-N-oxide was studied in the rabbit and the dog. The pattern of Koenig-positive substances in the urine of the animals suggested the presence of cotinine, demethylcotinine, hydroxycotinine, and allohydroxycotinine, compounds already previously identified as metabolites of (S)-cotinine and (S)-nicotine in many mammalian species. In the dog, 34% of the administered oral dose of (S)-cotinine-N-oxide was recovered from the urine, and 21% was recovered from the urine of the rabbit.

Regulation of Malate Oxidation in Isolated Mung Bean Mitochondria: II. Role of Adenylates.

Effects of ADP and ATP on products of malate oxidation in the presence or absence of respiratory inhibitors and an uncoupler were investigated in mitochondria isolated from mung bean (Phaseolus aureus var. Jumbo) hypocotyls. Changes in levels of products from malate oxidation generally correlated directly with changes in oxygen uptake.

Regulation of malate oxidation in isolated mung bean mitochondria: I. Effects of oxaloacetate, pyruvate, and thiamine pyrophosphate.

In order to investigate the relationship between malate oxidation and subsequent cycle reactions, the effects of oxaloacetate, pyruvate, and thiamine pyrophosphate on malate oxidation in mung bean (Phaseolus aureus var. Jumbo) hypocotyl mitochondria were quantitatively examined. Malate oxidation was optimally stimulated by addition of pyruvate and thiamine pyrophosphate, whose addition lowered the apparent Km for malate from 5 mm to 0.

Citric Acid cycle activity in mitochondria isolated from mung bean hypocotyls.

Citric acid cycle activity in mitochondria from mung bean (Phaseolus aureus var. Jumbo) hypocotyls were examined by surveying (a) characteristics of oxidation of cycle intermediates; (b) activities of cycle enzymes in mitochondrial extracts; (c) contents of cycle intermediates and electron transport components in isolated mitochondria; and (d) time-course changes of products formed during oxidation of succinate, malate, and citrate. Isolated mitochondria are deficient in thiamine pyro-phosphate and somewhat so in adenylates, but apparently sufficient in CoA, NAD, and electron transport carriers.

Nicotine-like actions of cis-metanicotine and trans-metanicotine.

The actions of the cis- and trans-isomers of metanicotine were observed on isolated rabbit aortic strips and ileal segments. The data are interpreted as showing a nicotine-like action on these preparations for both cis-metanicotine and trans-metanicotine. This hypothesis is supported in part by the demonstration that the action of the metanicotine isomers was affected by hexamethonium, cocaine, phenotolamine, reserpine and atropine in a manner similar to that previously seen in studies with nicotine.