Plasma testosterone in patients with varicocele and sexual inadequacy.

Plasma testosterone concentration was decreased in 10 patients combining varicocele with sexual inadequacy (mean 346.2 ng/100 ml) against normal concentration observed in 23 men with varicocele without sexual disturbances (mean 567.8 ng/100 ml) and in 31 patients with pure psychogenic impotence (mean 581.6 ng/100 ml). There was a significant inverse linear correlation between age and plasma testosterone concentration in the varicocele patients (r= minus 0.56, P smaller than 0.01) in contrast to the absence of such correlation in normal men or in patients with psychogenic impotence of the same age range. The secretion products of the secondary sex glands were more often in the lower range in the ejaculates of men combining varicocele with sexual disturbance (P smaller than 0.02), proving the decreased testosterone level to induce a deficient function of these glands. Plasma testosterone levels normalized after surgical correction in varicocele patients with a low preoperative concentration. Since adequate surgical or hormonal treatment resulted in complete recovery of sexual potency in the majority of patients with varicocele and sexual inadequacy, it is suggested that the decreased testosterone production might have contributed to the impairment of sexual function.


Effects of morphine on coronary and left ventricular dynamics in conscious dogs.

We studied the effects of i.v. 2 mg/kg morphine sulfate (MS) on coronary blood flow and resistance, left ventricular (LV) diameter and pressure (P), rate of change of pressure (dP/dt), and dP/dt/P in conscious dogs. An initial transient reduction in coronary vascular resistance, associated with increases in heart rate, dP/dt, dP/dt/P, and reductions in LV end-diastolic and end-systolic size were observed. This was followed by a prolonged increase in mean coronary vascular resistance, lasting from 5 to 30 min, while heart rate, arterial pressure, and LV end-diastolic diameter returned to control levels and dP/dt/P remained slightly but significantly above control. At 10 min, late diastolic coronary flow had fallen from 44 plus or minus 3 ml/min to a minimum level of 25 plus or minus 3 ml/min, while late diastolic coronary resistance had risen from 1.68 plus or minus 0.10 to 3.04 plus or minus 0.28 mm Hg/ml/min. Morphine also induced substantial coronary vasoconstriction when heart rate was held constant. Neither the MS-induced coronary vasoconstriction nor the positive inotropic response was abolished by bilateral adrenalectomy. The positive inotropic response of MS was reversed after beta blockade, but not the coronary vasoconstriction. Alpha receptor blockade abolished the late coronary vasoconstriction effects of morphine, and only dilatation occurred. In anesthetized dogs MS failed to produce late coronary vasoconstriction. Coronary after a respiratory-depressant dose of morphine, 10 mg/kg i.v. Smaller doses of MS, 0.25 mg/kg every 15 min, produced significant coronary vasoconstriction after a total dose of 0.75 mg/kg in the conscious dogs. The effects of morphine may differ in the normal dog and man and may vary depending upon the presence or absence of coronary artery disease. However, in the normal conscious dog, MS elicits a mild beta adrenergic increase in contractility and an important coronary vasoconstrictor effect, which is mediated through alpha adrenergic receptors.


Altered renin release and propranolol potentiation of vasodilatory drug hypotension.

Vasodilating antihypertensive drugs induce hypotension with reflex tachycardia, renin release, and fluid and electrolyte retention. Propranolol can impair this renin release. The studies described here were designed to determine the hemodynamic role of vasodilatory drug-induced renin release and inhibition thereof by propranolol in two animals models, the unanesthetized, normotensive and the unanesthetized, genetically hypertensive rat. In studies with normotensive rats, propranolol impaired renin release and tachycardia resulting from hydralazine and minoxidil and potentiated their hypotensive action. Two additional interventions against the renin-angiotensin system were used in evaluating the mechanism of this potentiation. One was removal of the renin source by nephrectomy, and the second was blockade of angiotensin's vasoconstrictor action using a selective angiotensin antagonist, saralasin (1-Sar-8-Ala-angiotensin II (previously known as P113)).. Both interventions potentiated vasocilatory drug hypotension, as did propranolol, but did not prevent reflex tachycardia. When combined with saralasin propranolol did not add to protentiation by this peptide. A similar pattern of blood pressure decrement and potentiation was seen in genetically hypertensive rats when propranolol or saralasin treatment preceded hydralazine. Propranolol was demonstrated to block hydralazine-induced increases in serum renin activity in genetically hypertensive rats. We conclude that hypotensive potentiation of vasocilating drugs by propranolol in these animal models is mediated to a large extent by impairment of renin release. Persistence of hypotensive tachycardia after nephrectomy and after saralasin in normotensive rats suggests the irrelevance of angiotensin's central nervous system stimulation to this cardiac effect. Clinical studies are underway to quantify the potential importance of this beneficial drug interaction in man.


The ionic control of 1,25-dihydroxyvitamin D3 production in isolated chick renal tubules.

Isolated renal tubules prepared from vitamin D-deficient chicks catalyze the 1 alpha-hydroxylation of 25-hydroxyvitamin D3 (250HD3) in vitro. The effect of calcium and phosphate on the rate of synthesis of the product, 1, 25-dihydroxyvitamin D3 (1,25(OH)2D3), was studied at two levels: the long-term effects of various dietary calcium and phosphate contents on the ability of the tubules to produce 1, 25 (OH)2D3, and the acute effects of different calcium and phosphate concentrations in the incubation medium on the rate of synthesis of 1,25(OH)2D3 by the tubules. Manipulation of dietary calcium and phosphate sufficient to produce marked changes in the concentration of calcium and phosphate in the serum led to altered rates of 1,25(OH)2D3 synthesis by the isolated renal tubules. The renal tubules isolated from chicks raised on a vitamin D-deficient diet containing 0.43% calcium and 0.3% P as inorganic phosphate showed the highest rate of synthesis of 1,25(OH)2D3. Diets containing more or less of either calcium or phosphate produced chicks whose renal tubules had a slower rate of 1,25(OH)2D3 production. The calcium, phosphate, and hydrogen ion content of the incubation medium were manipulated to determine the possible factors concerned with the immediate regulation of 1,25(OH)2D3 production. A calcium concentration of 0.5-1.0 mM was necessary for optimal enzymatic activity. Concentrations of calcium greater than this optimal concentration inhibited 1,25(OH)2D3 production if phosphate was also present, and this inhibition was more pronounced as the phosphate concentration was increased. The stimulation of 1,25(OH)2D3 production by calcium was less at pH 6.7 than at 7.4. Raising the phosphate concentration from 0 to 6 mM in the absence of calcium also stimulated the rate of synthesis of 1,25(OH)2D3. This stimulatory effect was blocked by 4 mM calcium. However, at 1-2 mM calciu, phosphate had a biphasic influence on 1,25(OH)2D3 production; extracellular concentrations of phosphate from 0.6 to 1.2 mM resulted in less 1,25(OH)2D3 production than higher or lower phosphate concentrations. This biphasic effect was seen both at pH 7.4 and 6.8.


The ionic control of 1,25-dihydroxyvitamin D3 synthesis in isolated chick renal mitochondria. The role of calcium as influenced by inorganic phosphate and hydrogen-ion.

Isolated kidney mitochondria prepared from Vitamin D-deficient chicks catalyze the conversion of 25-hydroxyvitamin D3 to 1,25 dihydroxyvitamin D3. It wasfound that changes in the concentrations of Ca-2plus, HPO4-2minus, and Hplus altered synthesis in an interrelated fashion. Increasing the Ca-2plus concentration from 10-6 to 10-5 M caused a four- to fivefold increase in 1 alpha-hydroxylase activity when the medium pH was between 6.5 and 7.0. increasing the [Ca2+] to 10-4 M caused to furhter stimulation. At higher pH values, Ca-2plus had little effect upon 1 alpha-hydroxylase activity. In the absence of calcium [Ca2+] less than or equal to 10-7 M), a change in pH from 6.5 to 7.1 had no effect upon 1 alpha-hydroxylase activity in the presence of 10-5 M calcium, increasing the medium pH had a biphasic effect. An increase in pH from 6.5 to 6.9 caused a 1.5-fold increase in 1 alpha-hydroxylase activity, but a further increase of the pH to 7.1 caused a profound decrease in rate of hydroxylation to approximately 20% of the peak value. Neither 10-5 M LaC13 nor 10 mug/ml of oligomycin altered the effects of Ca2+ upon hydroxylate activity. However, the effect of calcium was blocked by 2.5 times 10-5 M ruthenium red, 0.83 mug/ml of antimycin A, and 500 muM dinitrophenol. The clcium ionophore, A23187, decreased but did not prevent the stimulatory effect of calcium. These data are consistent with the concept that the [Ca2+ in the mitochondrial matrix space is of importance in regulating the 1 alpha-hydroxylase. Phosphate exerted a biphasic effect on 1,25(OH)2D3 production with maximal stimulation (approximately twofold) at 1-3 mM. Calcium enhanced the stimulation by phosphate at all concentrations studied. The presence of potassium modified the interrelated effects of calcium and phosphate in two ways: 10-3 M calcium blocked the stimulation by phosphate; and in the presence of phosphate, 10-3 M calcium resulted in less 1,25(OH)2D3 production by production by isolated mitochondria are qualitatively similar to the effects of these ions on 1,25(OH)2D3 production yb isolated renal tubules.


The mechanism of the natriuresis of fasting.

This study tests the hypothesis than obligatory cation coverage of metabolicaly generated anions is the mechanism for the sodium diuresis of fasting. Nine obese female subjects were equilibrated on a constant sodium and caloric intake and then fasted while sodium intake was maintianed. Particular activity schedule during fasting as during control. Consecutive 3-h increases in urinary sodium , ammonium, and potassium excretion during fasting were matched against simultaneously determined increases in organic acid anions (OAS) and H2PO4 minus, which would exist in combination with the cations. The changes were significantly correlated (r equals 0.891, P less than 0.001) in the relationship y equals 0.73x plus 19 where y equals increases in organic acid salts plus H2POJ minus and x equals increases in cations. As ammonium excretion rose, sodium conservation occurred with ammonium replacing sodium at the major urinary cation. Corollaries to the hypothesis were also found to be true. They were: (a) Increases in ammonium excretion lagged considerably behind increases in OAS plus H2PO4 minus during the diuretic phase making sodium coverage necessary. (b) Sodium loss was much greater than chloride although chloride balance was minimally negative. (c) After refeeding with glucose, sodium excretion promptly decreased and appeared best correlated with simultaneous decreases in OAS. Ammonium excretion also fell but much less than sodium. The data support the hypothesis that obligatory cation coverage of metabolically generated aniuns is a major mechanism responsible for the sodium diuresis of fasting.


The effect of anemia on the ventilatory response to transient and steady-state hypoxia.

The effects of anemia upon the ventilatory responses to transient and steady-state hypoxia were studied in unanesthetized goats. Responses to transient hypoxia (inhalation of several breaths of nitrogen) were considered to reflect peripheral chemoreceptor and non-chemoreceptor influences of hypoxia upon ventilatory control. In all goats, severe anemia (hemoglobin 3.1-4.8 g/100ml) markedly heightened the responses to transient hypoxia (from a mean of 0.27 to a mean of 0.75 liter/min/percent fall in SaO2). This phenomenon was substantially reversed by alpha-adrenergic blockade (phenoxybenzamine, 5 mg/kg). In contrast, the ventilatory responses to steady-state hypoxia were unaffected by severe anemia. These data suggest that severe anemia enhances the peripheral chemoreceptor-mediated response to hypoxia through a mechanism involving the alpha-adrenergic system. It also appears that a ventilatory depressant effect of hypoxia which is not mediated by the peripheral chemoreceptors is also enhanced by severe anemia, thereby preventing an increase in the steady-state ventilatory response to hypoxia. Finally, experiments involving variation in oxygen affinity of hemoglobin suggested that O2 tension rather than O2 availability in arterial blood is the major determinant of peripheral chemoreceptor activity.


Pneumococcal antigen in lobar pneumonia.

This paper describes the value in diagnosis and the clinical implications of the detection of pneumococcal antigen in patients with lobar pneumonia. Ninety-eight patients with lobar pneumonia were investigated. Pneumococcal antigen was detected by counter-current immunoelectrophoresis in the sputum of 79% of patients with purulent sputum, in the serum of 29% of the patients, and in the urine of 54% of the patients. The diagnostic value of counter-current immunoelectrophoresis was not affected by prior antibiotic therapy. Patients with antigenaemia had a higher incidence of complications than those without as shown by an association between antigenaemia and jaundice, diarrhoea, and persistent pyrexia. Antigen persisted in the circulation for at least seven days in half the patients studied, possibly indicating the development of immunological tolerance to the polysaccharide antigen.


A new method for the assay of factor XI in plasma and the preparation and use of a new artificial substrate.

An improved method for the one-stage assay of factor XI in plasma has been proposed; it is reproducible and compares well with an old, established method.A short investigation into the preparation and use of artificially prepared factor XI-deficient plasma has been carried out: this substrate can be used as an alternative to the congenitally deficient substrate.


The effect of angiotensin on myocardial contractility.

Previous studies of the effect of angiotensin on myocardial contractility have yielded conflicting results. Possible reasons for the observed disparities include differences in techniques for measuring contractility, in species (dog, cat, and man), in myocardial state (normal or diseased), in preparation observed (heart-lung, isolated heart, papillary muscle, atrial myocardium, intact heart), and in dosage schedule. Moreover, there are no reported studies in the intact human heart, normal or diseased, in which contractility measurements are based on velocity-force relations. To resolve the conflict, left ventricular myocardial contractility was measured using the same expressions for the force-velocity relationship in all subjects. Studies were performed in five normal human subjects, six patients with cardiomyopathy, eight normal mongrel dogs, and six dogs with ischemic myocardial scarring, before and during angiotensin infusions in dosages producing 15--20-mm Hg increases of aortic diastolic pressure. Contractile element velocity at peak, dP/dt (Vce) and the Frank-Levinson contractility index (CyIx), which normalizes Vce for diastolic fiber length, decreased during angiotensin infusion in all groups. The mean decreases (11 to 19) per cent in Vce, 15 to 23 per cent in CyIx, SEM's 4-5 per cent) were significant (P values ranging from smaller than 0.05 to smaller 0.005) in the normal hearts of dogs and man and in the scarred canine hearts, in which preangiotensin Vce and CyIx were normal. In the cardiomyopathy group, in which contractility was depressed before angiotensin, the drug elicited a further decrease in Vce (mean fall 17 plus or minus 7 per cent, P smaller than 0.1) and CyIx (26 plus or minus 8 per cent,  P smaller than 0.02). We conclude that, in the intact organism, with a normal myocardium or a diffuse or segmental myocardial disease, the administration of angiotensin results in a depression of contractility.


Fungal growth and acid production during fermentation and refermentation of organic acid treated corn silages.

Chopped corn (35% dry matter) treated with either propionic, formic, 60% propionic plus 40% formic, or 80% propionic plus 20% acetic acids at 0, .5, 1, and 2%, was placed in polyethylene bags inside metal drums, and evacuated. During fermentation silages were sampled and temperatures determined. On day 40 of fermentation silages were placed in open containers at 25 C and were sampled during refermentation. All samples were analyzed for volatile and lactic acids, pH, and number and type of fungi. Lactate fermentation was totally inhibited at 2% addition of all acids, but formic acid was more effective than propionic acid at .5 and 1%. Acerate production was equally depressed by both propionic and formic additions. Heating, growth of fungi, and days until spoilage were delayed by all acid additions during refermentation, with propionic more effectivethan formic. The large increases in lactate and acetate of treated silages during refermentation reflect a protection of soluble sugars during fermentation and subsequent use by microbes after exposure to air. Silages treated with more than 1%propionic (as propionic or a mixture) did not increase in fungal colonies during refermentation. At initiation of fermentation yeasts werehigher than other fungi but decreases by day 40. During refermentation, yeasts again grew. Geotrichum comprised 35% on day 40 of refermentation but was lower at other times. Aspergillus proliferated during refermentation and few Penicillium were detected.


Psychopharmacologic investigations in healthy elderly volunteers: effects of pipradrol-vitamin (Alertonic) elixir and placebo in relation to research design.

Ninety-nine healthy elderly volunteers were tested to assess the effects of: 1) a pipradrol-vitamin (Alertonic) elixir, 2) a placebo, and 3) no treatment, during a one-week period.  The assessment measures were the Minnesota Multiphasic Personality Inventory Depression Scale, the Zung Depression Scale, Profile of Mood States, and the WAIS Digit Span.  Alertonic had no sigmificant effects on mood, memory or appetite, and the placebo effect was rarely greater than 50 per cent.  There were no significant side effects.  The findings demonstrate a valid method for studying psychotropic agents in the elderly.


Diagnosis of Schistosoma bovis infection in cattle by an indirect haemagglutination test.

An indirect haemagglutination test has been developed for the detection of Schistosoma bovis antibody. Fresh, formalin and glutaraldehyde fixed sheep erythrocytes as well as fresh and formalin fixed human erythrocytes were tested. Tanned glutaraldehyde fixed sheep erythrocytes sensitized with an adult worm extract were the most sensitive and remained stable for at least 8 weeks at 4 degrees C. With such cells 98% of a group of S. bovis infected cattle were positive while negative results were obtained from cattle infected with other helminths.


Colloidal alpha-stannic acid and negative iron colloid as differential electron stains for surface proteins.

Colloidal alpha-stannic acid and a negative iron colloid obtained from ferric hydroxide and potassium ferrocyanide, both negative sols being stable within a wide pH range, were refined as surface protein electron markers. Because of the relatively small size of its particles, colloidal alpha-stannic acid was used for staining all surface proteins. According to the pH at which the negative iron colloid was applied, it revealed either all surface proteins, or because of its large colloidal particles, stained basic proteins. This differential staining capability of the iron colloidal has been demonstrated previously on various control preparations (Puvion E, Blanquet PR: J Microsc 12:171, 1971). Controls on the affinity of the two colloids to surface amino groups were carried out on rat liver, mouse fibroblasts, HeLa and KB cells, Ehrlich and Zajdela ascites cells subjected to prior enzymatic and chemical treatments (incubation with neuraminidase or phospholipase C, esterification, acetylation or lipid extraction). At any pH below 9, the two sols stained proteins in the outer hydrophilic leaflet of esterified cells with relative selectivity, but the alpha-stannic acid showed them more accurately. The iron sol did reveal at high pH protein components of high isoionic point on the surfaces of rat hepatocytes and ascites cells which had only been treated with neuraminidase.


The ultrastructural cytochemistry of lactic dehydrogenase, succinic dehydrogenase, dihydro-nicotinamide adenine dinucleotide diaphorase and cytochrome oxidase activities in hair cell mitochondria of the guinea pig cochlea.

The use of cinnamyl nitroblue tetrazolium chloride (DS-NBT) in dehydrogenase experiments (lactic dehydrogenase, succinic dehydrogenase, nicotinamide adenine dinucleotide diaphorase) and 3,3'-diaminobenzidine tetrahydrochloride (DAB) in cytochrome oxidase experiments indicated that mitochondrial oxidoreduction reactions from nicotinamide adenine dinucleotide to cytochrome oxidase are located on the inner mitochondrial membrane in the outer compartment and the intracristate spaces. These reactions behave according to the chemiosmotic hypothesis. The cochlear hair cell mitochondria are cytochemically indistinguishable from free liver mitochondria. The heterogeneous mitochondrial staining pattern is related to the osmolarity of the incubation media, solubility of the enzymes and pH of the medium, but not to the fixation method.


Immunobiological biochemical and physico-chemical characteristics of Brucella lipopolysaccharide subjected to various doses of gamma radiation.

A comparative study of toxicity, serological activity, some biochemical and physico-chemical properties of the highly toxic Brucella lipopolysaccharide (LPS) and of preparations obtained after the action of gamma radiation in doses of 1.3 and 10 mrad on the antigen. The toxicity of LPS was found to decrease with the increasing dose of irradiation. Irradiation with a dose of 3 mrad produced a marked decrease in the toxicity of the antigen without causing essential changes in its serological properties. The process of LPS detoxication under the effect of irradiation was accompanied by changes in certain biochemical and physico-chemical indices suggestive of the modification of the primary structure of the LPS molecule and of impairment of mainly its polysaccharide side chains.


Nationwide epidemic of septicemia caused by contaminated infusion products. IV. Growth of microbial pathogens in fluids for intravenous infusions.

Septicemia caused by contaminated infusion fluid is a newly appreciated hazard of intravenous infusion therapy. Microorganisms of the tribe Klebsielleae (Klebsiella, Enterobacter, and Serratia) have predominated in these infections. Members of this tribe found to possess a selecive ability over common non-Klebsielleae microbial pathogens to proliferate rapidly in commerical parential fluids contaning clucose at room temperautre. Fifty-one Klebsielleae strains, washed twice before inoculation of approximately 1 organism/ml, attained a mean normalized 24 hr concentration of 1.11 x 10-5 organisms/ml in 5% dextrose in water at 25 C. In contrast, 48 of 49 non-Klebsielleae bacterial strains (clinical isolates of Staphylococcus, Proteus, Escherichia coli, Herelea, and Pseudomonas aeruginosa) slowly died (mean 24-hr concentration, 0.2 organism/ml). Five Candida albicans strains frew only very slowly (31.3 organisms/ml). Even with concentrations exceeding 10-6 organisms/ml, microbial presence was never visibly detectable. The significant increases in cases of nosocomial spticmia caused by Klebsiella, Enterobacter, and Serratia in recent years might be attribuatble in part to fluid-related spesis accompanying the expanding use of parenteral therapy.


Immunogenicity of formaldehyde-inactivated enterotoxins A and C1 of Staphylococcus aureus.

Quantitative precipitation of antisera specific for native enterotoxin revealed that 70% and 60%, respectively, of the antigenic determinants of enterotoxins A and C1 of Staphylococcus aureus were inactivated by formaldehyde at pH 5.0 or 7.5 contained large polymers (excluded by Sepharose 2B) and induced strong humoral immune responses in rhesus monkeys. Enterotoxin A inactivated at pH 5.0 or 7.5 was composed mostly of small polymers (excluded by Sephadex G-100 but included by Sepharose 2B); it provoked a poor immune response in monkeys (about equivalent to the response obtained with weakly reactive toxin inactivated at alkaline pH). It was concluded that potent enterotoxoids were formed by extensive cross-linking of enterotoxin C1 into large polymers in acidic or neutral formaldehyde solution.


The pathogenesis of Shigella diarrhea. V. Relationship of shiga enterotoxin, neurotoxin, and cytotoxin.

The biological activity of the enterotoxin of Shigella dysenteriae 1 was compared with that of a well-studied 20-year-old partially purified preparation of neurotoxin from the same organism. Enterotoxicity, neurotoxicity, and cytotoxicity were present to an equivalent extent in both preparations. Human convalescent antisera and experimental rabbit antisera had equal toxin-neutralizing antibody to the cytotoxic activity in these toxin preparations. Multiple protein bands were present in each toxin studied. Two separate HeLa cell fractions could be obtained by Sephadex gel filtration chromatography, isoelectric focusing in a sucrose gradient, and polyacrylamide gel electrophoresis. Only one of these fractions (isoelectric at pH 7.2) was associated with enterotoxicity and neurotoxicity. The second smaller-molecular-weight fraction, which was isoelectric at pH 6.1, possessed only cytotoxic activity. These data suggest that Shiga enterotoxin and neurotoxin are closely related proteins and, indeed, may be identical. The nature of the cytotoxin with pH 6.1 is not clear, although it may be a subunit of the larger toxin that is capable of acting directly on the HeLa cell.


Control of sterol synthesis and of hydroxymethylglutaryl CoA reductase in skin fibroblasts grown from patients with homozygous type II hyperlipoproteinemia.

In skin fibroblasts grown from four children with a homozygous form of type II hyperlipoproteinemia, the feedback control of sterol synthesis and the inhibitory effect on hydroxymethylglutaryl (HMG) CoA reductase activity by serum or low density lipoprotein were present, though diminished compared with the effects in normal fibroblasts. Stimulation of HMG CoA reductase by insulin and inhibition of acetyl CoA carboxylase by serum lipids were not impaired in these type II cells, indicating a degree of specificity in the abnormal response of the reductase. A rapid and convenient method for isolation of mevalonolactone in the course of the assay of HMG CoA reductase is described.


Fatty acid binding to plasma albumin.

A review of the available information about fatty acid binding to plasma albumin is presented. Albumin is composed of a single polypeptide chain, folded so as to form three or four spherical units. The strong fatty acid binding sites probably are located in crevices between these spherical regions. The anionic form of the fatty acid binds to albumin. Most of the binding energy comes from nonpolar interactions between the fatty acid hydrocarbon chain and uncharged amino acid side chains that line the binding sites. The binding sites are somewhat pliable, and their configuration can adapt to fit the incoming fatty acid. Stepwise association constants for binding to human albumin of fatty acids containing 6-18 carbon atoms are presented. These data indicate that each mole of fatty acid binds with a different affinity and that the association constants for multiple binding diminish sequentially, i.e., kappa 1 greater than kappa 2 greater than kappa 3 greater ... greater kappan. Because of uncertainties concerning fatty acid association in aqueous solutions, the constants for the 14-18 carbon acids probably are not definitive. In the usual physiological concentration range, free fatty acids do not displace appreciable amounts of a second organic compound from albumin. Sensitive spectrophotometric analyses revealed, however, that even small increases in free fatty acid concentration alter the molecular interaction between human albumin and another organic compound.


Enzymatic synthesis of mannosyl retinyl phosphate from retinyl phosphate and guanosine diphosphate mannose.

A study was conducted to determine whether retinyl phosphate would act as substrate for the enzymatic synthesis of mannosyl retinyl phosphate. Retinyl phosphate, prepared chemically, supported the growth of vitamin A-deficient rats at the same rate as retinol. It also stimulated the uptake of [14C]mannose from GDP-[14C]mannose into total chloroform-methanol extractable lipid. This reaction occurred in the presence of ATP, Mn2+, detergent (Zonyl A), and a membrane-rich enzyme preparation from the livers of vitamin A-deficient rats, provided that a lipid extract of the membrane preparation of alpha-L-lecithin was also added. Total chloroform-methanol-extractable, labeled mannolipid was separated into two principal labeled mannolipids by thin-layer or column chromatography or by differential solvent extraction. The properties of these mannolipids identified them as glycophospholipids: one was identical with authentic synthetic dolichyl mannosyl phosphate, and the other was concluded to be mannosyl retinyl phosphate because of its incorporation of radioactivity from [3H]retinyl phosphate, its rapid hydrolysis by dilute acid, and the formation of substance that cochromatographed with retinol upon its acid hydrolysis. The presence of ATP or GTP was essential for the stimulation of mannolipid synthesis, probably because of their protective action on the substrates against phosphatases present in the crude enzyme fraction. A pH of 6.0-6.2 favored the formation of dolichyl mannosyl phosphate; a higher pH (6.7-7.0) that of mannosyl retinyl phosphate.


Subcellular localization and heterogeneity of neutral proteases in neutrophilic polymorphonuclear leukocytes.

The subcellular localization of elastase and of neutral proteases hydrolyzing histone and casein was determined in human and rabbit polymorphonuclear leukocytes using fractionation by isopycnic centrifugation. Granule-rich fractions obtained by this technique were extracted and analyzed by acrylamide gel electrophoresis, and proteolytic activity on the gels was demonstrated by staining with either N-acetyl-D,L-alanine alpha-naphthyl ester or naphthol AS-D acetate as substrate. In both species, all neutral proteases assayed were found to be localized exclusively in the azurophil granules. Specific activities were about 10-30 times higher in human than in rabbit preparations. In extracts of human azurophil granules up to 10 proteins exhibiting esterolytic activity could be demonstrated after electrophoretic separation. Three major and two or three minor components of these esterases were shown to possess elastase activity. Similar zymograms prepared with extracts from rabbit azurophil granules revealed only one major elastase band. The electrophoretic analysis further showed that the most strongly cationic proteins of both human and rabbit PMNs were also confined to the azurophil granules.


Lymphocyte-induced angiogenesis: a quantitative and sensitive assay of the graft-vs.-host reaction.

A new and sensitive assay for the effect of intracutanous administration of immunocompentent lymphocytes into the skin of irradiated unimmunized mice is described. The assay, which we have termed lymphocyte-induced angiogenesis (LIA) involves enumeration of new vascular branches induced by the action of these competent cells. As is the case for the previously described normal lymphocyte transfer reaction, LIA is a manifestation of the graft-vs.-host reaction, as shown by experiments utilizing appropaiate genetic combinations. The reaction is dose-dependent, and within the dose range of 2 times 10 minus 5 -4 times 10-6 cells the mumber of vessels induced correlates with the mumber of immunocompetent cells injected. At these dose levels spleen, lumph node, and hydrocortisone-resistant  thymocytes are effective; bone marrow and thymus cells are not. Spleen cells from nude mice are incapable of inducing LIA, while mitomycin-C and irradiated lymphocytes can initiate but not maintain the reaction. The relationship between lymphocyte-induced angiogenesis has been discussed as have the implications of these findings to delayed hypersensitivity, inflammation, and vascular pathology.


Cell membrane-binding properties of group A streptococcal lipoteichoic acid.

Lipoteichoic acid (LTA) was extracted from group A streptococci, previously treated with hot HCl, by the phenol method. The extracted LTA was loaded on an isoelectric (IE) focusing column and two fractions were collected; one at pH 4.65 and the other at pH 2.95. Chemical analysis demonstrated that the unfractionated LTA contained alanine and glycerolphosphate at molar ratio of 1:10, and ester-linked lipids, but no detectable sugars or amino-sugars. The two IE fractions contained lipids but lacked alanine. The LTA and its IE fractions spontaneously adsorbed to human erythrocytes (sensitization) causing them to agglutinate in the presence of rabbit anti-LTA. The RBC-sensitizing and antigenic activities of IE fractions were equal to, or greater (for IE fraction at pH 4.65) than the unfractionated LTA, indicating that alanine is not involved in the sensitizing activity of LTA. Mild ammonia-hydrolysis abolished the RBC-sensitizing activity of LTA and its IE fractions. Chloroform-methanol-soluble material of the ammonia-hydrolysate lacked antigenic activity but blocked sensitization of erythrocytes by LTA. The water-soluble material of the hydrolyzed LTA retained antigenic activity, was not able to block sensitization by LTA, and its sensitizing activity was restored after esterification with fatty acids. These experiments indicate that ester-linked fatty acids (palmitic acid being the major one) are involved in the spontaneous adsorption of LTA to erythrocytes. The LTA, its lipid moiety, and anti-LTA blocked adherence of group A streptococci to human epithelial cells, suggesting that small amounts of LTA may reside on the streptococcal surface to mediate attachment and colonization of these organisms on mucosal surfaces in vivo.


The opsonic fragment of the third component of human complement (C3).

Human peripheral blood phagocytes ingest Escherichia coli 026:B6 lipopolysaccharide (LPS)-coated paraffin oil droplets containing Oil red O only if fresh serum deposits C3 on the surfaces of the particles (opsonizes them), by reactions involving the properdin system. The rate of binding of purified [125-I]C3 in serum to LPS-coated particles correlated precisely with the rate of acquisition of ingestibility assayed spectrophotometrically. Once opsonized, LPS-coated particles remained fully ingestible and retained fixed [125-I]C3 radioactivity even after exposure to extremes of temperature, pH, ionic strength, phospholipases, urea or guanidine, some nonionic and ionic detergents, and organic solvents. Trypsin, human conglutinogen-activating factor, another heat-stable activity found in human serum, and sodium dodecyl sulfate removed radioactivity and diminished ingestibility of the opsonized particles. Alkylation, reduction plus alkylation and F(ab')2 from anti-C3 blocked ingestibility but did not alter particle-bound radioactivitymelectrophoretic and tryptic peptide autoradiographic analysis of dodecyl sulfate eluates of opsonized particles, cleansed of many contaminating proteins by boiling with 2 M NaCl (yet still opsonized), revealed that the polypeptide with C3-derived radioactivity had a mol wt of approximately 140,000 and was composed of 70,000 mol wt subunits linked by disulfide bonds. Immunochemical analysis and comparison of the peptide structure of the eluate with that of C3 indicated that the opsonic fragment is not the fragment defined as C3b but a smaller derivative of C3.


Primex trainees under stress.

In summary, it seems clear from the data presented in this report that nurses engaged in becoming a family nurse practitioner in the program studied undergo a considerable amount of social, physical, and psychological discomfort.  However, the data on the first class trained does suggest that the psychological and to a lesser extent the physical stress students experience during formal training subsides during the preceptorship.  Nevertheless, it is out contention that certain stressful periods in training cannot be avoided because of the nature and intensity of the course content as well as the role change necessary for becoming a responsible, dicisive practitioner.  Yet, experience with training two classes does suggest that although high stress probably cannot be avoided, at least the length of intense periods can be shortened.  In order to accomplish this, it is necessary to have a curriculum which is well-organized, clear in its purpose, and one which provides the opportunity for tension-release, discussion and development of role, and emotional support.  Finally, with regard to the perisitence of social stress both during and after training, there appears to be a need to provide continued support to students during their preceptorship in order to assure that role change and development continues.  In this regard, periodic continuing education sessions for students seem crucial as do discussions of role with both students and preceptors.  As the family nurse practitioner role evolves, it becomes increasingly clear that at times these new health professionals are neither doctors or nurses and at other times they are both.  However, nurse practitioners cannot meaningfully sustain their new and somewhat ambiguous role without the mutual cooperation and support of both the medical and nursing establishments in which they practice.


Teaching nursing management by programmed instruction.

Student and faculty dissatisfaction with lectures prompted several revisions of teaching methods for nursing management.  Revisions centered around a programmed text for business plus various methods of application to nursing.  One part of management (control) was also programmed in nursing terms.  Data collected revealed that students who used the programmed business text and participated in small group discussions achieved significantly higher scores than either students who attended lectures or used the programmed business text in conjunction with a tutorial system.  Data also demonstrated that students who used the unit programmed specifically for nursing management achieved significantly higher scores than students who used the programmed text for business management.  This data suggest students level of achievement is increased when the transfer step from business to nursing is eliminated.  For this reason, two faculty members completed the writing of a programmed text for nursing management.  This text has been tested over the past two years and will be published in the near future.  We were unable to collect objective data regarding the actual application of management principles to nursing practice.  Subjectively, we felt the students had a stronger framework of principles unique to nursing management and were able to transfer this knowledge to leading a team with greater ease than previously.  Without student dissatisfaction originally, and student acceptance and participation throughout the changes, this study would not have evolved.  It was student encouragement which prompted the program specific to nursing.


Distal renal tubular acidosis in infancy: a bicarbonate wasting state.

Three unrelated infants with apparently distal RTA were investigated. Growth retardation, polyuria, nephrocalcinosis, inappropriately high urinary pH, and marked dependence of bicarbonate excretion on urinary flow were characteristic of the distal or classic form of RTA, but the urinary loss of bicarbonate at normal serum values exceeded that usually found in children or adults with this disorder. Renal tubular function was studied during hypotonic saline diuresis in the three patients and in seven healthy control infants of similar age. Fractional delivery of sodium to the distal nephron was significantly higher in the patients than in control subjects. Sodium transport at the diluting segment was not impaired. The results support the assumption that the bicarbonate wasting was the consequence of an increased delivery of this substance to an already impaired distal nephron and thus further inhibited the distal mechanisms of net acid excretion.


Coronary aneurysms in infants and young children with acute febrile mucocutaneous lymph node syndrome.

In 1967, Kawasaki, in Japan, first described a new syndrome affecting infants and young children-an acute, febrile illness with mucocutaneous involvement associated with swelling of cervical lymph nodes. The prognosis is usually good but recently it has become evident that 1-2 percent of the patients die suddenly from acute heart failure. Infantile polyarteritis (nodosa-like arteritis) accompained by coronary aneurysm and thrombosis has been noted in postmortem examinations. Twenty patients surviving the illness were examined by coronary angiography; 12 of the 20 had abnormal coronary angiograms; seven patients had coronary aneurysms. Complete regression of the coronary aneurysms was proved in two patients at subsequent angiography. One patient developed mitral regurgitation as a result of papillary muscle dysfunction. One had a coronary aneurysm without symptoms two years after the onset of illness.


Bisulfite-ion-catalyzed degradation of fluorouracil.

5-Fluorouracil (I) reversibly adds bisulfite ion across its greater than C5 equals C6 smaller than bond to form 5-fluoro-5,6-dihydrouracil-6-sulfonate (II). The pH-independent equilibrium constant for this reaction was calculated to be 560 M-1 at ionic strength 1.00 M at 25 degrees. Compound II was observed to be unstable in alkaline solution and reacted to yield uracil-6-sulfonic acid, fluoride ion, and alpha-fluoro-beta-ureidopropionic acid-beta-sulfonate (III), along with I (via a loss of HSO3 minus). In strongly alkaline conditions, i.e., 1 M NaOH, III was observed to undergo a subsequent reaction to produce a compound believed to be alpha-fluoro-beta-ureidoacrylic acid (V) or fluoromalonaldehydic acid (VII). These irreversible degradation reactions of II lead to a complete degradation of I in sodium bisulfite solutions. The similarity of this bisulfite-ion-catalyzed degradation of I to its hydrolytic degradation is discussed.


Practical kinetics I: Quantitation of barbiturate stability by TLC.

The purpose of this work was the application of established techniques to the quantitation of stability investigations of liquid formulations as well as in solution kinetic studies. The process consists of streaking aliquots of reaction solution on TLC plates, development, elution, and analysis of the substances in the eluate. Several barbiturates were investigated regarding their decomposition at elevated temperatures. Reasonable correlation is noted between obtained rate constants and literature data. This technique represents a utilitarian approach to stability screening of compounds in solution, aqueous or otherwise, where chromatographic separation and analytical methodology for the pure compound are available.


Practical kinetics II: quantitation of procaine stability by TLC.

This work illustrates further application of TLC as a tool in kinetic investigations of organic molecules. The procedure consists of: (a) streaking or spotting a known volume of reaction solution on thin-layer plates, (b) developing the plates, (c) eluting the compound under study from the adsorbent, and (d) assaying the material in solution. Procaine was examined regarding its hydrolysis at above ambient temperatures. The reaction was monitored spectrally and by the TLC technique. Velocity constants derived by the two methods were similar in value. Rate constants obtained from procaine samples eluted from silica gel plates following development were in good agreement with those previously reported in the literature.


Practical kinetics III: benzodiazepine hydrolysis.

The velocity constants for chlordiazepoxide hydrolysis were measured by independent techniques. A quantitative TLC kinetic procedure is compared with an extractive method. The data derived from both processes are in approximate agreement, further exemplifying the feasibility of TLC for rapid stability evaluation of liquid formulations as well as solution kinetic studies. In the extractive procedure, benzodiazepine-substrate was separated from the lactam product by methylene chloride extraction of acidic aqueous solution. The TLC procedure consisted of separation on silica gel plates followed by elution and subsequent analysis. The log kappa-pH relationship for the hydrolysis representing water addition coupled with expulsion of methylamine is presented. This function is characterized by water and hydroxide-ion attack on monoprotic species along with specific hydrogen-ion catalysis at higher hydronium-ion concentrations, and the rate law for the decomposition of chlordiazepoxide is given. Trhrough several half-times (pH 0.15-11.5, 79.5 degrees), this hydrolytic reaction generating lactam predominated; however, more benzophenone was formed as the pH decreased. Velocity constants were invariant over a 200-fold concentration range. The subsequent acid-facilitated cleavage of lactam to benzophenone was not further investigated. Both general acid catalysis and general base catalysis were evidenced, with borate, acetate, formate, and phosphate buffers accelerating the conversion of chlordiazepoxide to lactam. At pH values below neutrality, nonlinear dependency of the rate constant on buffer concentration was observed. This finding may be explained by a change in the rate-determining step as buffer concentration varied.


New color reaction for determination of bacitracin in ophthalmic ointments.

A colorimetric method was developed for the rapid analysis of bacitracin in ophthalmic ointments. The method involves the oxidation of alpha-aminocarboxylic acid with sodium hypobromite in an alkaline medium and condensation of the resulting aldehyde with phloroglucinol in concentrated hydrochloric acid to yield a pink color which gives an absorbance maximum at 505 nm. The relationship between absorbance and the quantity of bacitracin reacted obeyed Beer's law over the 15-100-mug/ml concentration range studied, and the produced color was stable for several hours. Furthermore, the method, which can be applied directly to the aqueous dissolution sample, gave results comparable to the official microbiological analytical procedure. The standard deviation is equal to plus or minus 1.81%.


Liquid chromatography of clindamycin 2-phosphate on triethylaminoethyl cellulose.

The separation of clindamycin 2-phosphate from clindamycin 3-phosphate, clindamycin 4-phosphate, clindamycin B 2-phosphate, and lincomycin 2-phosphate was achieved by liquid chromatography on triethylaminoethyl cellulose using a 254-nm monitor. The compounds have low molar absorptivities at 254 nm (smaller than 17), and UV detection is made possible by the high capacity support triethylaminoethyl cellulose. Linear peak height response versus concentration allows rapid quantitation of clindamycin 2-phosphate.


Conversion of agroclavine to setoclavine and isosetoclavine in cell-free extracts from Claviceps sp. SD 58 and in a thioglycolate-iron (II) system.

Agroclavine was converted to setoclavine and isosetoclavine in crude extracts from Claviceps sp. SD 58. The ratio of setoclavine to isosetoclavine was 0.95. The conversion with boiled crude extract was 68% of the conversion with unboiled extract. In a thioglycolate-iron (II) system at 40 degrees for 5 hr, 45.5% of agroclavine was converted to setoclavine and isosetoclavine. At 70 degrees for 4 hr in the thioglycolate-iron (II) system, 4% of 4-dimethylallyltryptophan was converted to clavicipitic acid.


Determination of stability constants of stannous fluoride complexes by potentiostatic titration.

The stability constants for stannous fluoride complexes were determined by potentiostatic titration. The method involves incremental additions of fluoride wherein each addition is followed by titration with stannous such that there is no change in the electromotive force developed between the fluoride ion and the reference electrodes. The values obtained were beta1 equals 4 times 10-3, b2 equals 1.1 times 10-7, and b3 equals 1 times 10-9. The results of this work suggest that the potentiostatic method wound be useful for determining stability constants in complexation systems involving an ion for which a specific on electrode is available.


Indolizines II: search for potential oral hypoglycemic agents.

A few 1,2-bis(N-alkylaminomethyl)indolizines, simple indolizinecarboxylic acids, and several 6-alkoxyindolizine-2-carboxylic acids were synthesized and screened as possible oral hypoglycemic agents. The absence of any significant hypoglycemic activity excludes these compounds from the predicted structural lead provided by some hypoglycemic Vinca alkaloids, such as vincamine, vindoline, and vindolinine, having the indolizine ring as one structural component. But an extension of the rationale that indolizines are also the structural components of some carcinolytic Vinca alkaloids, such as vincristine and vinblastine, used in cancer chemotherapy provided encouraging results. One indolizine derivative showed significant antineoplastic activity in Ehrlich ascites carcinoma.


Renal function in sheep during infusion of alkali metal ions into the renal artery.

1. The effect on renal function of 1 M solutions of LiCl, NaCl, KCl, RbCl and CsCl and 3 M-NaCl infused close-arterially to the kidney for 10 min at 0-7ml./min has been studied in nine experiments on four unilaterally nephrectomized sheep. The levels of flow, electrolyte concentration and electrolyte excretion in the urine were measured before, during and for 50 min after the infusions. 2. The infusion of 1-M-NaCl produced little change in urine flow and composition whereas 3 M-NaCl resulted in relatively small increases in urine flow and sodium excretion. 3. The infusion of lithium, potassium, rubidium and caesium resulted in marked increases in urine flow, urinary sodium concentration and excretion, urinary potassium excretion and osmolal clearance while the urinary potassium concentration decreased. 4. Changes in urine flow and urinary pH during the infusions of all the alkali ions except sodium were consistent with increased urinary bicarbonate excretion. 5. The osmolal clearance was increased by the infusion of lithium, potassium, rubidium and caesium, but equivalent increases in the rate of solutefree water reabsorption did not occur. 6. The infusion of caesium resulted in a depression of the glomerular filtration rate (G.F.R.) which was not observed when the other alkali ions were infused. 7. The effects of lithium, potassium and rubidium on urine flow and composition were rapid in onset and the residual effects on these ions, on cessation of infusion, were relatively short. The effects on caesium were slow in onset and prolonged in duration. 8. It was concluded that lithium, potassium, rubidium, and caesium altered urine flow and electrolyte excretion by acting upon common mechanisms which were predominantly intra-renal and located in the proximal segment of the nephron.


[Takayasu's disease (aortic arch syndrome). Usual and unusual angiographic appearances. Report of 15 cases treated by arteriography (author's transl)].

The authors report 15 cases including 9 controlled by autopsy, and discuss the usual and unusual angiographic appearances in this disease. These cases strictly fulfilled the criteria necessary for diagnosis. The two angiographic forms seemed to correspond to different therapeutic indications. Takayasu's disease remains a disease of young women and the angiographic diagnosis can only be made during the obstructive phase.


[Aortic arch syndrome. Stenosis and obstruction of the sub-clavian artery in women (author's transl)].

Takayasu's disease evolves in two stages: The pre-obstructive state: frequently it gives rise to infectious diseases which often resemble rheumatic fever. Often there exist fever and joint pains. Laboratory examinations show the presence of an inflammatory process: increased ESR hypoalbuminuria and increased alpha-2 and gammaglobulins. Then one reaches the obstructive stage. Here the diagnosis of the disease is often suspected or confirmed. Often there are eye signs with the characteristic appearance of arteriovenous anastomoses in the fundus oculi. These signs were absent. The etiology is unknown. The authors propose the following definition: that this is a form of juvenile arteritis occurring, above all, in women and involving one or other of the main aortic trunks, but which may be diffuse. The disease is often inflammatory. The etiology is unknown.


Effect of long-term addiction to heroin on oral tissues.

The oral health status of 36 long-term heroin addicts was measured using DMF, OHIS, and PI. Comparisons were made utilizing data from the National Center for Health Statistics. Age, sex, race, education, income, and geographic location were compared. The former addicts exhibited a significant increase in DMF, with significantly higher missing and decayed teeth, and fewer filled teeth. The periodontal condition of the former addict also showed health status. It would appear that long-term heroin addiction either contributes directly to lowered oral health status, or more likely, causes individuals to lead a life style which has ramifications to their oral health.


Causes of accidental injuries to the teeth and jaws.

Almost one half of all the dental accidents recorded during this study occurred when the victim was moving and struck a stationary object. Falls and vehicles were about equally responsible for half of the accidents. Accident proneness seemed to be affected by age and sex with the teenage group reporting the most dental accidents (35.76%) and males reported dental accidents three times as often as females. Of orthodontic patients, 16.43 percent had a history of dental accidents in contrast to about five percent of the general population. From the limited data available, approximately three fourths of the persons reporting said no seat belts were available in their automobiles. The remaining one fourth had belts but they were not being used at the time of the dental injury. Right-handed victims tended to be injured on the right side of the mouth and jaw and left-handed victims exhibited more injuries on the left side. As was anticipated, a high percentage (23 percent) of the residents of a hospital for the mentally retarded exhibited dental injuries.


The removal of the seminal vesicles from the boar and the effects on the semen characteristics.

A technique is described for the removal of the seminal vesicles from the boar. The operation was carried out on twelve animals and six of the animals were subsequently trained for semen collection. The seminal plasma from the boars after surgery compared with normal litter mates had a more watery consistency and did not form the characteristic gelduring ejaculation. The sperm concentration was 49% lower while the total reduction of sperm number ejaculate was 78% in the experimental animals, but the ratio of living to dead spermatozoa remained unchanged. The concentrations of citrate and protein were significantly depressed in the seminal plasma of the animals after surgery and the pH increased; the osmolarity remained unchanged. In semination of gilts with the semen from experimental boars revealed no significant loss of fertility compared with the normal controls. Animals slaughtered up to 17 months after surgery showed no regeneration of the seminal vesicles.


A solid medium for culture and identification of human T-mycoplasmas.

A solid urea-containing medium buffered to pH 6.5 with a suitable mixture of KH2PO4 and Na2HPO4 produced enlarged T-mycoplasma colonies containing a white precipitate. This was absent from M. hominis colonies. The medium can be used for the isolation and identification of T-mycoplasmas.


Impedance monitoring of bacterial activity.

Bacterial activity and growth were monitored by following the changes of electrical impedance of cultures in liquid media. The signal is expressed automatically as a curve similar to grwoth curves produced by other methods. The technique offers a new, rapid and sensitive means of detecting active micro-organisms and is potentially the basis of rapid automated systems in this field. The impedance changes indicate that the micro-organisms metabolise substrates of low conductivity into products of high conductivity and that the changes are due to the activity of the micro-organisms rather than increase in their numbers. The activity of strains of Escherichia coli, Klebsiella aerogenes, Pseudo-monas aeruginosa, Staphyloccus aureus, and Streptococcus faecalis was detected within 2 h with inocula of 10-3 minus 10-5 organisms per ml. Different reactions of bacteria in various media suggest that the method may be applied to the rapid identification of micro-organisms. The inhibitory effect of antibiotics on bacteria was demonstrated within 2 h, indicating that the method may be useful for the rapid determination of bacterial sensitivity to antibiotics and the rapid assay of antibiotics in serum. Correlation of response time to initial inoculum allows estimatin of numbers of viable organisms. The sensitivity of the method allowed detection of activity due to Myoplasma argininii within 3 h; this suggests that the method might be applicable to the rapid detection of other slowly growing organisms, such as mycobacteria.


Human placental aryl hydrocarbon hydroxylase: studies with fluorescence histochemistry.

Tissue sections from human placentas taken at term were studied after time-sequential incubations with benzo[a]pyrene and appropriate cofactors for mixed-function oxidation. Fluorescence microscopy revealed that the enzymic reaction appeared to be most active in the syncytial trophoblast, though the fluorescence of hydroxylated metabolites also could be observed in other placental cell types. A comparison of sections from placentas with very low versus very high aryl hydrocarbon hydroxylase activities provided evidence that induction of the human placental enzyme system with pol7cyclic aromatic hydrocarbons also appeared to occur primarily in the syncytium. When considered in conjunction with previous studies on human placental aryl hydrocarbon hydroxylase, the results tended to indicate that fetal elements of the human placenta contain the necessary electron-transport components for catalysis of mixed-function oxidations of chemical carcinogens and other foreign compounds and that this hydroxtlase system is readily inducible in the same fetal cells by components present in cigarette smoke.


Disappearance of nitrite from the rat stomach: contribution of emptying and other factors.

To help understand how intragastric nitrosation forms N-nitroso compounds, nitriet disappearance from the rat stomach was measured after food containing nitrite was given. In preliminary experiments, nitrite disappearance from buffered aqueous solutions became more rapid as the pH was lowered from 5 to 1 and, at a given pH, was more rapid in a slurry of commercial rat food. The disappearance of nitrite from buffer was little affected by the addition of pepsin, mucin, albumin, or rat gastric contents. When starved rats were given 5 g food with 1.82 mg nANO3/g, nitrate was not reduced to nitrite in the stomach. Five g food containing 154 mug NaNO2/g was administered similarly, and the total stomach (T) and glandular and nonglandular parts (G and NG) were analyzed after 1.5 hours. Weight and nitrite concentration of the stomach contents dropped linearly and the amount of nitrite dropped exponentially (with a half-life of 1.4 hr). Mean nitrite concentration in G was less than half that in NG. From similar experiments with phenol red, emptying accounted for 60% of nitrite loss from T. In G, nitrite concentration was reduced about 3 times due to dilution and 3 times due to other causes. Conditions in G, e.g., nitrite concentration, pH, and empyting time, were discussed in relation to carcinogenesis experiments with nitrite plus amines and amides.


Transplantation behavior of allotransplantable tumor lines derived from immunologically modified hosts.

The strain-specific BALB/c tumor C4092 was conditioned to grow in H-2 incompatible DBA/1 mice by prior maintenance in vitro as an organ culture explant. It then was serially transplantable in DBA/1 mice and regained its specificity with one passage in BALB/c mice. Changes in transplantation behavior were similar in  vivo if the recipients were conditioned by neonatal thymectomy, immunologic enhancement, rabbit antimous serum treatment, or immunization with mitomycin C-inactivated C4092 tumor cells. In vivo- and in vitro-modified tumors differed in degree of transplantability and in the stability of immunogenic changes. However, because of conspicuous similarities in the behavior of these lines, it was concluded that ADAPTations of both host and graft ultimately contribute to graft survival.


Proteases during the growth of Ehrlich ascites tumor. II. The kallikrein-kinin system.

Ascitic fluid and ascites tumor cells from Swiss mice bearing Ehrlich ascites tumor were assayed for components of the kallikrein-kinin system at various times during tumor growth. Changes in component levels were correlated with those in the plasma. Ascitic fluid contained an acetone-activated prekallikrein that increased in concentration during tumor growth and reached peak levels during the 7th-10th day post transplant. No free kinin activity was present in the ascitic fluid. During tumor growth, kininogen levels increased in parallel with prekallikrein levels. The ascitic fluid also contained a kinin-destroying activity that was initially high during the early phase of tumor growth. Tumor cell fractions, prepared by ultracentrifugal techniques, had no kinin-forming activity while possessing kinin-destroying activity that was localized in the soluble protoplasmic protein and nuclear fractions. The kinin-forming activity of the ascitic fluid resembled that of the plasma with respect to pH optima, kinetics of kinin formation, and effect of protease inhibitors. The kininase activity of both ascitic fluid and plasma differed from that of the tumor cell fractions.


Reaction of nitrite with ascorbate and its relation to nitrosamine formation.

In this study of the nitrosation of morpholine in the presence of ascorbic acid, the amount of ascorbate required to inhibit completely the formation of nitrosomorpholine depended on whether oxygen was present in the system. The nitric oxide (produced during the oxidation of ascorbate by nitrous acid) might have reacted with oxygen to yield additional oxidizing equivalents, or oxygen might have directly oxidized the ascorbate semiquinone intermediate produced in the initial step of oxidation reaction. A pH- dependent induction period observed during the nitrosation of morpholine in the presence of ascorbate and excess nitrite was accounted for by the kinetics of the reactions.


Chemical studies on tobacco smoke. XXXIII. N' -nitrosonornicotine in tobacco: analysis of possible contributing factors and biologic implications.

A chemical analytic method to determine N'-nitrosonornicotine (NNN) and N' -nitrosoanabasine (NAB) in tobacco was developed. NNN was found in the unburned tobacco of commercial products at concentrations betweeen 0.3 and 88.6 mug/g. The highest levels were observed in highly fermented snuff (29.1 mug/g) and fine-cut chewing tobacco (88.6 mug/g). NAB was not detected (smaller than 0.5 ng/g) in any tobacco examined. Two new tobacco components, N' -carbomethoxynornicotine and N' -carbomethoxyanabasine,were found. Possible origins of NNN in tobacco were discussed, especially in relation to concentrations of nitrite, nitate, and alkaloids, and in relation to pH and curing. Biologic implications, including the possible function of NNN (the first organic carcinogen isolated from unburned tobacco) as a causative factor in cancer of the oral cavity in tobacco chewers and betel quid chewers, were also discussed.


Dilutional re-expansion with crystalloid after massive hemorrahage: saline versus balanced electrolyte solution for maintenance of normal blood volume and arterial pH.

When administered in sufficient amounts, normal saline and Lactated Ringer's Solution are equally effective in maintaining adequate circulatory volumes despite severe blood loss and resultant hypoproteinemia. Arterial pH is maintained within normal limits when either solution is used for resuscitation provided the circulatory volume has been re-expanded to adequate levels for good tissue perfusion and support of aerobic metabolism. The pH of the infused solutions has no effect on blood pH under these circumstances. Fourteen splenectomized dogs were subjected to continuous hemorrhage and simultaneous replacement with either normal saline or Lactated Ringer's Solution. The cumulative replacement volume ratio necessary for equilibration after 61% RBC depletion was 7:1 crystalloid to the whole "undiluted" blood shed, in both groups. Indicators of pulmonary-circulatory physiology remained stable within normal limits. Arterial pH did not exhibit significant changes from normal values after resuscitation with NS or LRS. The group infused with LRS exhibited no change in arterial pH, 7.40 plus or minus .07 initial and 7.40 plus or minus .09 final; in the group with NS replacement a slight decrease from control was noted, 7.40 plus or minus .07 initial and 7.36 plus or minus .06 final. These differences, however, are not statistically significant. Of the 14 subjects, 13 were long-term survivors. The one death was associated with a technical mishap shortly after completion of the experiment. Because banked blood imposes a "net" alkaline metabolic load (sodium citrate), patients expected to be transfused with large volumes of stored blood might be better resuscited with normal salin than with Ringer's Lactate Soultions, to minimize or avert the otherwise resultant metabolic alkalosis.


Immunotherapy of malignancy in humans. Current status.

Many observations support the premise of a close relationship between immunologic competency and the growth of human cancer. Immunotherapy against cancer in animals has been established. Its function appears to be adjunctive to other treatment modalities that first lower tumor burden. These findings are demonstrated in both clinical and laboratory studies of cancer in humans. At the present time, intralesional injections of BCG vaccine in immunocompetent patients with intradermal metastases are most effective. Immunotherapy with topical administration of 2,4 dinitrochlorobenzene is the treatment of choice in selected patients with squamous or basal cell carcinoma.


Testicular function in XYY men.

A previous survey of 48 subjects with XYY chromosome complement showed a wide scatter of values for plasma concentration of testosterone and luteinizing hormone (LH). To account for this scattering and in view of the impulsive behavior often attributed to XYY subjects, it was postulated that paroxysmal activity in the cerebral cortex produced paroxysmal stimulation at the level of the hypothalamus. To investigate this possibility, plasma concentrations of testosterone, dihydrotestosterone, follicle stimulating hormone (FSH), and LH were determined on seven consecutive days in four XYY subjects and five XY control men as well as bimonthly for four months in two XYY detainees and three XY control detainees. The variability of plasma androgen and gonadotropin levels in XYY subjects was similar to that of XY control men. The results thus do not support the above hypothesis as an explanation of the widely scattered plasma androgen values in XYY individuals. The "XYY syndrome" is probably heterogeneous and includes a number of patients with some degree of hypogonadism. Testicular biopsy, sperm count, and meiotic studies were carried out in eight XYY men. In one case the meiotic study showed two Y-chromatin bodies. Results of these various investigations support the diagnosis of maturation arrest of the germ cells with consequent oligospermia. Low fertility is therefore expected to be frequent among XYY subjects, although when fertilization does occur, it can result in normal XY or in XYY infants.


Two forms of guanylate cyclase in mammalian tissues and possible mechanisms for their regulation.

All mammalian tissues examined to date have two forms of guanylate cyclase with apparently different properties. From the studies in several laboratories, we suggest the following mechanisms for the possible regulation of guanylate cyclase activity: (1) factors that could alter the apparent cooperative nature of the enzyme, (2) interactions of metal ions with the substrate or enzyme, (3) factors that could overcome inhibition by ATP, (4) mechanisms that could regulate the interconversion of latent and active forms of the enzyme, (5) possible translocation of particulate and soluble forms of the enzyme, and (6) induction or repression of the enzyme.


Gentamicin as a bactericidal antibiotic in tissue culture.

The effects of gentamicin on cellular physiology were studied in a total of 9 mammalian cell lines, using the following parameters: cell morphology and viability (cytotoxicity), proliferation, culture medium acidification, lactic acid production, lactate dehydrogenase release, virus susceptibility, and effects on karyotype. With regard to cytotoxicity no gross differences could be found in the sensitivity of the diploid and aneuploid cells investigated, as judged by morphological criteria. However, cells exposed to the antibiotic in the lag-log phase of growth showed damage at lower concentrations (1000 mug/ml) than cells treated in the stationary phase (2000 mug/ml). As regards the influence of gentamicin on cell growth and metabolsim, dose-response relationship were found proving that the antibiotic causes a depression of proliferation, a striking increase in lactate production, an elevated LDH release, and changes in pH behaviour. All these parameters were unaffected by concentrations up to 125 mug/ml. No gross changes in chromosome morphology and number could be detected in huploid cell line after 10 passages with 50 mug/ml gentamicin in lieu of the usual penicillin plus streptomycin combination. The minimal bactericidal concentrations (MBC) were determined in cell-free media and in tissue cultures against 4 species of bacteria. The MBC of gentamicin was generally lower as compared with the penicillin plus streptomycin combination. In some instances MBC was higher in the presence than in the absence of ti-sue culture cells. Comparison of the bactericidal efficiency against 31 strains of 7 species of bacteria of gentamicin (50 mug/ml) and penicillin plus streptomycin (100 units plus 100 mug/ml) in cell cultures proved that gentamicin is superior for control of bacterial growth in tissue culture.


Kinetic studies on the depolymerization of polyadenylic acid by ribonuclease A.

Studies were conducted on the depolymerization of polyadenylic acid (poly (A)) by RNAse A (EC 3.1.4.22) depending on the pH (pH 5-8). The results showed that depending on the pH, the ratio Vmax/Km was analogous to that described earlier for nucleoside-2', 3'-cyclophosphates and dinucleoside phosphates. This indicates that depolymerization of poly (A), transesterification and hydrolysis of specific substrates is achieved by the same ionizing groups of the enzyme with pKa 5.4 and pKb 6.4. The rate of degradation of poly (A) is also influenced by the state of adenine ionization, the protonation of which leads to the formation of a double helical poly (A), and does not serve as a substrate for RNAse A. The low rate for the depolymerization of poly (A) in the presence of RNAse A is related to a decrease in the turnover number of the enzyme, and an increase in the molecular weight of the enzyme (RNAse dimer), leads to a decrease in the Km, and does not effect Vmax. This indicates that the rate of depolymerization of polynucleotides is determined by orientation of factors. On the basis of the comparison of the resultant kinetic data, and the structure of the enzyme inhibitory complexes of RNAse S, which were studied by the method of x-ray structural analysis, a conclusion was reached on the kinetic characteristics of RNAse A specificity with respect to polymeric substrates, which is determined by the orinetation of the ribose phosphate relative to the catalytic groups of the active site.


Investigation of the conformational lability of serum albumin macromolecules in aqueous solution by the NMR spin-echo method.

The complex proton spin-echo decay curve was recorded for human serum albumin (SA) solutions with different concentrations in normal and heavy water. The curve included three fast-decaying components for SA, in addition to the slow-decaying component for the water. The total amplitude of these three components roughly corresponded to the number of protons in the SA (with isotopic exchange taken into account); the component ratio remained constant at different concentrations and different temperatures between 4 and 39 degrees. The relatively slow-decaying protein component, which accounted for similar to 10% of the SA protons, was produced by the side chains of the protein. The presence of two other faster-decaying SA components with approximately equal amplitudes indicated that only about half of the remaining protons in the SA macromolecule are incorporated into the comparatively rigid globule, the other half belonging to groups with high conformational lability in aqueous solution. The activation energy for the aqueous component was close to that for pure water, while the activation energies for the protein components were roughly twice as large.


Pyruvate kinase from human skeletal muscle.

A simple method is described for the isolation of crystalline pyruvate kinase from human skeletal muscle. The enzyme was purified by ammonium sulfate fractionation, heat treatment and crystallization. Two crystal forms of pyruvate kinase differing in solubility but not in specific activity were found. The homogenous enzyme preparations in triethanolamine buffer, pH 7.6 reveal at 25 degrees a specific activity of 245 U per mg protein, and of 340 U/mg in potassium phosphate buffer (50 mM). The enzyme is activated by inorganic phosphate and fructosediphosphate to the same extent, and inhibited non competetively by ammonium ion. The molecular weight as measured by gel filtration is 220,000 daltons and the enzyme molecule is composed of 4 subunits.


A new two-dimensional gel electrophoresis system for the analysis of complex protein mixtures: application to the ribosome of E. coli.

A new method for two-dimensional polyacrylamide gel electrophoresis of proteins is described. The method, illustrated here by its application for the analysis of ribosomal proteins of E. coli, has a high resolving power. The proteins S15 and S16 can be resolved either following alkylation or under reducing conditions. This was not possible with urea gel systems previously employed. The method should be advantageous in the identification of the components of dimers formed with the reagent methyl 4-mercaptobutyrimidate. An additional advantage of the new method is that both dimensions are run at an acidic pH. For ribosomal proteins it is therefore unnecessary to either polymerize the protein sample in the middle of the first dimension disc gel or to electrophorese two samples with opposite polarity.


[LH-RH Test in prepuberal children (author's transl)].

The LH-RH test was performed in 62 mainly prepuberal children. A dose of 25 mug/20 kg was given intravenously between 10 and 12a.m. Prepuberal healthy boys between 1 11/12 and 9 7/12 years of age reacted with a fourhold increase of LH. Prepuberal boys with an unilaterally undescended testicle showed no difference in LH response from normal. Even a low increase in LH may be followed by spontaneous puberty in children with pituitary dwarfism. The LH response in children with craniopharyngeoma was heterogeneous and appeared to depend on location of tumor and extent of operation. Birdheaded dwarfism and small stature due to steroid administration and due to unknown etiology showed normal LH responses for age. Cases with anorchia and myotonic dystrophy had an excessive LH increase. The LH response in children with Fanconi's anemia and undescended testicles and in otherwise healthy boys with undescended testicles was normal for age. A case of untreated adrenogenital syndrome without salt loss had a presumably normal increase of LH when related to bone age. Primary and pituitary hypothyroidism was shown to have a higher than normal output of LH. A boy with a tumor the 3rd ventricle hat basal levels of LH that were extremely elevated and associated with precocious puberty and diabetes insipidus. A newborn infant with anencephalus showed no increase of LH and LH-RH injection.


Renin release, saralasin and the vasodilator-beta-blocker drug interaction in man.

Saralasin, an angiotensin antagonist, was used to study the role of renin-angiotensin in the vasodilator-beta-blocker drug interaction in hypertensive subjects. Plasma renin activity was elevated by withdrawal of propranolol in seven patients using minoxidil and propranolol. After propranolol withdrawal, saralasin caused hypotension (100/60 mm Hg or less) in five. Propranolol lowered blood pressure and plasma renin activity and diminished the hypotensive response to saralasin. Saralasin induced renin release in all patients, an effect blocked by propranolol. We conclude that angiotensin can be the major determinant of blood pressure in vasodilator-drug treated patients, that propranolol lowering of blood pressure in this vasodilator-beta-blocker drug interaction is related to suppression of renin release, and that the angiotensin feed-back-suppression mechanism for inhibiting renin release in functionally located proximal to beta-adrenergic receptors mediating renin release.


A career in ambulatory medicine.

To meet the need and resolve long standing conflicts in the delivery of primary care in an age of specialization, I propose an experiment with a different type of primary medical education based on the separation of careers into community-oriented primary and continuing care of ambulatory patients and hospital-based intensive care of acutely ill bed patients. High-school graduates selected for interest, aptitude, and personality would follow a six-year pathway through college and medical school. A singular feature of the proposal would be the replacement of bedside training with an undergraduate traineeship of two to 2 1/2 years in the hospital ambulatory specialty clinics, emergency clinic, and a primary-care model practice unit, followed by a one-year externship in this primary-care center. The graduate would be oriented toward group and team practice and would work in a system integrating primary, secondary, and tertiary care.


The congress and health manpower: a legislative morass.

To correct deficiencies in physicians' services, chiefly related to geographic maldistribution and overspecialization, numerous bills have been introduced in both the House and the Senate. These bills would increase the annual number of medical graduates, would mandate service in areas defined as lacking in physicians, and would promote the training of primary-care physicians as opposed to more specialized training. The number of foreign medical graduates would also be restricted. Almost all this legislation potentially may diminish the quality of medical education without substantially affecting the provision of health service. Recently introduced legislation (HR 3279), however, seems to deal more rationally with the problems of health manpower.


Clinical aspects of bilateral renal dysplasia in children.

Despite recent attempts to improve classification and to provide data on pathogenic mechanisms, there is a paucity of information concerning the clinical aspects of bilateral renal dysplasia.  Therefore, the clinical features and long-term prognosis of eight patients with bilateral renal dysplasia have been evaluated.  Three important observations were made, namely (1) a large proportion of patients had an impairment of urinary concentration and acidification, (2) the clinical course was characterized by progressive renal deterioration in patients with bilateral involvement, and (3) four children with renal dysplasia had the clinical features of Laurence-Moon-Biedl syndrome.


[Anti-platelet aggregating drugs in the prevention of thromboembolic diseases].

The treatment and prevention of arterial thrombosis have been improved in recent years by the use of drugs acting on certain platelet characteristics, such as clumping capacity, adhesivity, release of factors 3 & 4, and survival.  Many substances have been proposed for clinical employment.  Mechanisms of action are discussed on the basis of personal experience, particularly with dipyrimadol and beta-blocking drugs.  It would seem that the best results are obtainable with drugs whose effect on platelet clumping comes from stablisation of the membrane, such as the non-steroid anti-inflammatory preparations, in association with drugs than enhance intraplatelet cyclic AMP.


[Verapamil in the study and treatment of supraventricular tachycardias, with special reference to pre-excitation].

Verapamil is a novel antiarrhythmic agent which appears to act as a calcium-ion antagonist, blocking calcium transport across the myocardial cell membrane. It was given intravenously, in a dose of 10 mg, to thirty-two patients suffering from paroxysmal supraventricular tachycardia, and sinus rhythm was achieved promptly in all. Identical results were obtained in a further ten patients with supraventricular tachycardias associated with the Wolff-Parkinson-White or other pre-excitation syndromes. In a separate group of eighteen patients in whom A-V junctional tachycardias were induced during intracardiac electrography, conversion to sinus rhythm was achieved in fifteen patients, with prolongation of the cycle length in the others. Circus-movement tachycardias were induced in eight patients with the Wolff-Parkinson-White syndrome, and conversion to sinus rhythm was achieved in seven. The results were less consistent in patients with other supraventricular arrhythmias including ectopic atrial tachycardia and atrial flutter, and, in the single patient with supraventricular and ventricular tachycardias, only the former was controlled. In the single patient with atrial fibrillation complicating the wolff-Parkinson-White syndrome who received Verapamil, sinus rhythm was restored. Side effects were few and mild, with rare exceptions of profound hypotension, bradycardia and asystole; their management is discussed, and reasons are advanced why their occurrence is likely to be related either to the concomitant administration of beta-adrenergic blockers or to the presence of sinoatrial disease. It appears that Verapamil is particularly suitable for the treatment of supraventricular tachycardias due to a circus movement as calcium antagonism is likely to be most effective in the N region of the atrioventricular node.


A double blind trial of nitrazepam and flurazepam as sedatives.

A double-blind cross-over trial was conducted using flurazepam and nitrazepam as sedatives in a group of a dozen psychiatric in-patients. The results show highly significant differences between placebo effects and the active drugs. The differences between the two drugs were not significant apart from the subjective estimate of time slept in which flurazepam was superior. As other studies have confirmed also their safety, relative lack of side effects and very low addictive potential it seems there is little to choose between them, except for the possibility that flurazepam may be preferred subjectively.


[Gasometric determination of total CO2 using and adapted syringe].

It seemed to us interesting to study the results supplied by a new apparatus designed for gasometric estimation of total CO2 in biological fluids according to a technique derived from that of Van Slyke. The main qualities observed are: linearity (10 to 40 mM/l); rapidly (20 estimations in 35 minutes), reliability (coefficient of variation 1.6% over 15 estimations), daily reproducibility (2 standard deviations = 2 mM/l), satisfactory correlation with a colorimetric method using orthocresolphtalein adapted to SMA 6/60 (r = 0.90) and with an indirect method leading to total CO2 levels by calculation from pH and pCO2 (r = 0.92). However, this technique is difficult to use in pediatrics for the samples of plasma cannot be less than 0.5 ml.


Growth retardation in children with ulcerative colitis: the effect of medical and surgical therapy.

The growth of 37 children with ulcerative colitis have been analyzed. While conventional growth charts showed only percentile changes in height, height data plotted on Tanner et al.'s growth charts showed increases and decreases in growth velocity. Growth retardation is a prominent complication of ulcerative colitis with onset on bowel symptoms. Both ulcerative colitis and "high-dose" steroid therapy (greater than 12 mg/sq m/day of cortisol) can hinder growth but in some instances there is a growth spurt after high-dose steroid therapy. "Low-dose" steroid therapy does not retard growth. Colectomy is more effective than high-dose steroid therapy in reversing the growth retardation caused by ulcerative colitis and is of greatest value if not delayed too long. Growth following subtotal colectomy with ileorectal anastomosis (Aylett procedure) is not likely to be as much as that after subtotal colectomy with ileostomy. Growth retardation is infrequently the only indication for surgical intervention but ileostomy and colectomy are appropriate for this complication of ulcertive colitis in itself when not improved by adequate medical treatment.


Pneumothorax and pneumomediastinum in infants with idiopathic respiratory distress syndrome receiving continuous positive airway pressure.

A review of infants with idiopathic respiratory distress syndrome developing pneumomediastinum and pneumothorax reveals (1) an incidence of 20% in patients receiving CPAP with an 11% incidence in comparable infants not receiving this mode of therapy; (2) in the CPAP-treated group the occurrence was at a stage in the illness when the inspired oxygen concentration was being lowered and when ventilation was stable; (3) the inspired oxygen concentration in the CPAP group at the time of the PM and/or PT was 52% (plus or minus S.D. 15%) at a mean age of 33 hours (plus or minus S.D. 23 hr). These observations suggest that distending airway pressure creates excessive alveolar distention as an underlying mechanism of the air leak. It is recommended that distending airway pressure be lowered prior to achieving an inspried oxygen concentration of 60%. A controlled study is in progress to delineate the optimum distending airway pressures at specific inspired oxygen concentrations in order to reduce the incidence of alveolar rupture to a minimum.


Prevention of apnea and bradycardia in low-birthweight infants.

The efficacy of theophylline in preventing severe apnea was evaluated in 17 low-birthweight infants (mean weight, 1,400 gm).  Apnea was detected and accurately quantified by 13-hour pneumogram recordings and correlated with serum theophylline levels.  Nursing observations coupled with on-line alarm systems detected only 39% of severe apneic episodes as compared to the pneumogram recording technique.  Theophylline in six hourly oral doses(1.5 to 4.0 mg/kg) yielded two-hour serum concentrations of 6.6 to 11.0 mug/ml which completely controlled apneic spells exceeding 20 seconds in duration and markedly reduced 10- 19-second apneic episodes and any resultant bradycardia.  At these serum levels, toxicity was not observed.  Therapy with theophylline should be instituted at a dose of 2 to 3 mg/kg every six hours and the optimum therapeutic dose should be individualized as determined by objective quantitation of apnea and serum theophylline concentration.


Laryngeal chemosensitivity: a possible mechanism for sudden infant death.

In 32 anaesthetized piglets 1 to 42 days of age the distal trachea was cannulated and pressure changes were recorded.  The proximal trachea was cannulated for introduction of test fluids into the laryngeal area.  Arterial pressure, heart rate, and central venous pressure were continuously recorded.  Arterial blood samples were obtained at intervals and analyzed for PO2, PCO2, pH, and hematocrit.  Normal saline produced no, or brief, transitory alterations of the respiratory pattern and arterial pressure.  In contrast, instillation of distilled water produced apnea in 29 of 30 piglets.  In 20 the apnea was sustained.  Eleven died within approximately 50 minutes of asphyxia.  An additional nine were expected to die with continuing apnea (PO2, 10 to 15 mm Hg; PCO2 greater than 100 mm Hg; pH smaller than 6.8) but the sequence was interrupted by replacement of water with saline.  Twenty-three of 29 piglets showed an apneic response to cow's milk similar to that seen with distilled water.  Seven died of asphyxia and an additional three showed sustained respiratory inhibition until milk was replaced with saline.  The responses were completely abolished by superior laryngeal nerve (SLN) sectioning.  Electrical stimulation of the SLN produced sustained apnea in seven of eight piglets tested.  Studies in two 3-day-old lambs showed similar discrimination but only transitory apnea with water or cow's milk.  Both died during SLN stimulation.  Two ewes showed insignificant responses.  These findings suggest a lethal reflex mechanism with implications for the SIDS problem.


[Serum gamma-glutamyl-transpeptidase and alcoholism. Diagnosis and control of withdrawal].

The gammaGT of a generally healthy population is abnormally high due to the presence of ethanol in the diet. We confirm Rosalki's finding that a high proportion of alchoholics show an increased gammaGT activity. After alcohol deprivation, the gammaGT of alcoholics decreases in the first few days according to an exponential law with a half-time of return to normal of 5-17 days. Among past alcoholics, those who stopped drinking for a year have a lower GT activity (mean: 21 mU/ml) than a generally healthy population and in the range of Szasz's reference values. Alcoholics who did not stop drinking have a higher gammaGT activity (mean: 172). Ascitic cirrhotics who drink at least 1 liter of wine per day have also a high activity (mean: 139) while those who stopped drinking for at least 2 months have a much lower activity (mean: 49) and those who stopped for a year a normal activity. In 10 out of 11 alcoholic cirrhotics who stopped drinking, the gammaGT decreased (half-time: 11-54 days). These results show that the determination of gammaGT activity is a good test for the detection of ethanol impregnation.


Protonated polynucleotide structures.  16. Thermodynamics of the melting of the acid form of polycytidylic acid.

A phase diagram (pH, ionic strength, temperature) for the double helical form of poly(C) is presented. The thermo-dynamic analysis of these data shows that poly(C) behaves essentially as cytidine, if the electrostatic (ionic strength) contributions and the free energy of double helix formation are considered and taken into account.


Size fractionation of double-stranded DNA by precipitation with polyethylene glycol.

We show that DNA molecules of differing molecular mass are separable by selective precipitation with polyethylene glycol (PEG+.. Higher molecular mass DNA precipitates at lower PEG concentrations than lower molecular mass DNA. Double-stranded DNA can be fractionated at least in the range of 3 times 10-7 to 1 times 10-5 daltons. The effects on PEG concentration, sodium chloride concentration, DNA concentration, pH, divalent ions, precipitation time, and centrifugal force have been determined. These studies show PEG precipitation offers a size fractionation method for DNA which is convenient, of high capacity, and applicable over a wide range of conditions. However, resolution is not high and separation of two species approaches 100% only if they differ in molecular mass by at least a factor of two.


Transfer RNA methyltransferases from yellow lupin seeds: purification and properties.

tRNA methyltransferases from extract of yellow lupin seeds were purified over 300-fold by the methods based on hydrophobic and affinity chromatography. However, in the most active fractions the methylating enzymes were over 2000 purified. The purified enzyme fractions catalysed the formation of 1-methyladenine and 5-methylcytosine using E. coli B and B. subtilis tRNAs as substrates and S-adenosylmethionine as the methyl donor. They were unable to methylate their own endogenous tRNA but they were capable of methylating tRNA of some other lupinus species. Whereas the patterns of methylated constituents of tRNA of some other lupinus and B. subtilis were quite similar, they differed considerably from those obtained with lupin species tRNAs. Some properties of purified methyltransferases from yellow lupin seeds have been described.


The interaction of ribonuclease T 1 with DNA.

The interaction of RNase T1 with calf thymus DNA was studied using uv difference spectroscopy and the effect of the enzyme on DNA melting. There was no indication of RNase T1 binding with native DNA. A prominent difference spectrum for RNase T1 binding with denatured DNA (d-DNA) was observed at pH 5, 25 degrees and low ionic strength (mu = .01 M) which was depressed at higher ionic strength and pH. The normalized difference spectrum at mu = .01 M, pH 5 and 25 degrees can be interpreted as indicating an interaction of an exposed guanine residue directly with the enzyme and a coupling of this process with the "melting" of short folded segments of d-DNA. The apparent association constant calculated per M guanine residues was 2.4 X 10-4 M-1 under these conditions. The results are discussed in reference to comparable studies on the interaction of RNase T1 with RNA and small guanine ligands.


Studies on human tRNA. I. The rapid, large scale isolation and partial fractionation of placenta and liver tRNA.

A procedure for the large scale isolation of mammalian tRNA has been applied to the isolation of several grams of human liver, human placenta, rabbit liver and rat liver tRNA. This procedure entails an initial grinding of the tissue in phenol-sodium acetate at acidic pH, followed by DEAE cellulose chromatography. Procedures are also described for analysis of the purified tRNA on the basis of size, using controlled pore glass bean columns. In addition, the acceptor activity of isolated tRNAs has been determined using both the heterologous and homologous synthetases. The chromatographic profile of individual isoaccepting species using BD cellulose chromatography is shown and the 3' terminal nucleoside content was also determined. The methods described now make it feasible for large scale studies of mammalian tRNA enabling us to better understand the relationships between the structure of mammalian tRNA and its many diversified functions.


Genetic heterogeneity in familial hypercholesterolemia: evidence for two different mutations affecting functions of low-density lipoprotein receptor.

Studies in cultured fibroblasts from patients with the clinical syndrome of homozygous familial hypercholesterolemia have disclosed two different mutations affecting the functions of the low density lipoprotein receptor. One of these mutations, described previously, results in a functionless receptor that does not bind low density lipoproteins. In the cells of six patients who appear to be homozygous for this mutant allele, i.e., receptor-negative homozygotes, low density lipoproteins neither suppress hydroxymethylgultaryl-CoA reductase (NADPH) [mevalonate:NADP+ oxidoreductase (CoA-acylating) EC 1.1.1.34] activity nor stimulate cellular cholesterol esterification, even when examined in the presence of concentrations of lipoprotein 500 times higher than those cells. The second type of mutation, described herein, results in a receptor that has a reduced but not absent function. Fibroblasts from three subjects who possess this mutation, i.e., receptor-defective homozygotes, show partial suppression of the same enzyme activity and a detectable increase in cholesterol esterification capacity in the presence of high levels of low density lipoproteins. It was calculated that their degree of function could be achieved if they possessed only about 10% of the normal binding of low density lipoprotein. This level of binding was too low to be reliably detected by the 125-I-labeled low density lipoprotein binding assay. The finding of a second class of mutant cells in which a defect in low density lipoprotein binding is associated with simultaneous defects in both suppression of hydroxymethylglutaryl-CoA reductase activity and stimulation of cholesterol ester formation provides further evidence for the coordinate control of these two processes by the low density lipoprotein receptor.


[Conditions of dextranase formation by Penicillium funiculosum 15].

The influence of the following factors on the synthesis of extracellular dextranase by Pen. funiculosum 15 has been studied: the quantity and age of the inoculum, pH of the cultivation medium, stimulants of the microbial growth, cultivation temperature and time.  The optimal amount of dextranase has been found to form under the following conditions: inoculum--3 day mycelium constituting 4%, cultivation time--4 to 7 days, temperature--28 to 29 degrees C, initial pH of the medium--6.0.