Activated oxygen species and oxidation of food constituents. Activated oxygen species which may be important in initiating oxidative changes in foods include singlet oxygen, hydroxyl radical, ozone, superoxide anion (perhydroxyl radical at low pH), and hydrogen peroxide. Chemical and enzymic reactions known to occur in biological materials can generate singlet oxygen, hydroxyl radical, superoxide anion, and hydrogen peroxide. Ozone is primarily a product of photoreactions in polluted air. Reactions involving singlet oxygen, hydroxyl radical, and ozone with food constituents can ultimately yield peroxides which decompose to initiate oxidative chain reactions. Superoxide anion and hydrogen peroxide are relatively inert toward organic molecules but can decompose to produce the more reactive singlet oxygen and hydroxyl radical. Inhibition of reactions initiated by reactive oxygen species in foods should be very important in preserving the oxidative stability of foods. The generation, detection, measurement, reaction, and inhibition of reactions of active oxygen species are surveyed in this review.


Decubitus ulcers: a comparative study.

Decubitus ulcers: a comparative study. Seventeen patients with thirty-four decubitus ulcers were treated with dextranomer, collagenase, or sugar and egg white. All seven patients in the dextranomer group and two of five patients in the collagenase group improved at the end of the study, but none of the five patients on sugar and egg white treatment improved. Although collagenase can be helpful in the treatment of decubitus ulcers, dextranomer is significantly better.


Effect of metal ions on growth and sporulation of Clostridium perfringens in a synthetic medium. All cells, whatever their origin, function in an essentially inorganic environment. In this environment, metal cations play an important role. Attempts were made in the present study to determine if different amounts of five metal ions (MG++, Fe++, Mn++, Zn++, Ca++) are needed for secondary metabolism of Clostridium perfringens than are needed for primary metabolism. Both the vegetative growth stage (primary metabolic stage) and spore stage (secondary metabolic stage) of Clostridium perfringens were studied. Endeavors were made to detect the effects of metal ions, if any, on growth and sporulation of the organisms. Mg++ was required for growth of vegetative cells and maintenance of normal cellular morphology, Fe++ was needed for sporulation as well as for vegetative growth, but the amount needed for spore formation was higher than that needed for growth. Ca++ was essential to refractility and heat-resistance of spores. Zn++ inhibited both growth and sporulation, if the Mg++ concentration was low. Mn++ was required for neither growth nor sporulation. For maximum heat-resistance of the spores, Ca++ plus unidentified organic substances were required.


Cholinergic mechanisms and short-term potentiation. Acutely prepared rabbits were used to study, electrophysiologically, tetanic and post-tetanic potentiation of the pathway from the medial septal region to hippocampal field CA1. It was found that tetanic potentiation, evoked by short stimulus trains, was maximal at 6--8 Hz. Responses recovered from post-tetanic potentiation in 5--35 seconds. Acetylcholine, physostigmine, and cyclic GMP each had an excitatory effect on pyramidal cell responses when applied in stratum radiatum. The time course studies showed that these effects outlasted the duration of the injection current by many minutes. Phosphodiesterase inhibitors (e.g., isobutyl methyl xanthine) prolonged the time course of recovery with test responses which were post-tetanically potentiated. K+, on the other hand, selectively enhanced tetanic potentiation. It is suggested, with respect to the potentiation phenomena, that K+ acted primarily presynaptically to facilitate transmitter release, whereas cyclic GMP acted primarily postsynaptically for the enhancement of pyramidal cell excitability.


Neuronal aspects of septo-hippocampal relations. In unanaesthetized, conscious rabbits, in unstressful conditions, the neurons of the hippocampus and septum were investigated extracellularly during the presentation of a series of varied sensory stimuli. In the normal hippocampus these stimuli evoke habituating reactions of tonic (more usually, inhibitory) type in field CA3, with the addition of 'specific' patterned, and phasic reactions in field CA1. After complete septo-hippocampal disconnection the proportion of tonic (especially, of inhibitory) reactions in the hippocampus decreases. Theta bursts in the neuronal activity are absent; reactions to repeated sensory stimuli do not habituate. After lesion of the cortical perforant path to the hippocampus the majority of reactions in both fields are of tonic type. The proportion of neurons with regular theta bursts increases. Habituation is completely absent. A high correlation appears between the sensory reactions and the effects of midbrain reticular formation stimulation in the same neurons. The combination of both lesions does not significantly change the spontaneous activity of hippocampal neurons (except for the absence of the theta bursts). An increase in the level of activity of hippocampal neurons (by physostigmine), or rhythmic stimulation of the remaining synaptic systems, does not restore their rhythmic theta activity. In the septum deprived of hippocampal input the normal level of reactivity to sensory stimuli and the normal types of reaction are preserved. The proportion of neurons with theta bursts increases. The typical linear and rapid habituation of reactions disappears and is replaced by an unlimited increment in effects during repeated presentations of sensory stimuli. Discussion concerns the synchronizing and inhibitory influences of the septum on the hippocampus, and the role of the hippocampus in the organization of decremental processes (habituation) in the septum and brainstem structures.


Long-lasting facilitation of synaptic transmission. After tetanization of several hippocampal pathways (10--50 Hz for 5--15 seconds) there is an increased synaptic transmission of long duration (long-lasting facilitation). The present investigation was undertaken on isolated hippocampal slices to study the mechanism of the effect. The transverse hippocampal slice preparation in vitro allows the simultaneous testing of several afferent fibre systems on the same cell or population of cells. Tetanization of one group of afferent fibres to CA1 pyramids was followed by a long-lasting increase of synaptic transmission along the same fibres, whereas a control input line gave unchanged responses. Using the presynaptic volley as an indicator of the number of afferent impulses, the increased synaptic transmission appeared as an increased excitatory postsynaptic potential (EPSP), increased amplitude and reduced latency of the population spike, and an increased probability of firing of single units. Intracellular recording showed increased EPSPs to afferents of the tetanized line, but no lasting change in membrane resistance or in the response to a depolarizing current pulse. Thus, the effect cannot be ascribed to a general postsynaptic excitability increase. The specific changes in the synaptic transmission may be due either to an increased amount of liberated transmitter or to a local postsynaptic change near the tetanized synapses.


Polypeptide hormone-receptor interactions: the structure and receptor binding of insulin and glucagon. Insulin is a small globular protein with a well defined tertiary structure which is closely similar in all species with the exception of certain hystricomorphs such as the guinea pig. Insulin-like growth factor is homologous with insulin and probably has an insulin-like tertiary structure. In contrast glucagon is not a globular protein. It exists as an equilibrium population of conformers with low helix content at physiological concentrations but attains a largely helical conformation on association to trimers. The receptor binding of insulin depends critically on the correct three-dimensional juxtaposition of groups (A1, A21, B25, etc) and involves both hydrophobic and polar interactions. In insulin-like growth factor part of the insulin receptor region is thought to be buried in extra peptide, so explaining its weak binding to insulin receptors. In contrast the glucagon receptor complex probably involves largely hydrophobic contacts which are possible when a helical conformer is formed.


The free radical in ribonucleotide reductase from E. coli. Protein B2, one of the subunits of ribonucleotide reductase from Escherichia coli, contains a stable free radical. It is characterized by a doublet e.p.r. signal centered around g = 2.0047 and a sharp peak at 410 nm in the optical spectrum. The radical has been assigned to a tyrosyl residue in the protein with its spin density delocalized over the aromatic ring. Protein B2 also contains two antiferromagnetically-coupled high-spin iron(III) atoms, which stabilize the free radical. Protein B1, the other subunit of ribonucleotide reductase, contains two binding sites for substrate molecules, which are the four common ribonucleoside diphosphates. It also contains two classes of allosteric effector-binding sites. ATP and deoxyribonucleoside triphosphates function as effectors. A one-to-one complex of proteins B1 and B2 forms the enzymically-active ribonucleotide reductase. The free radical is, most likely, part of the active site.


The chemical properties of out-of-equilibrium states of proteins and the role of these states in protein functioning. The out-of-equilibrium states of several iron-containing proteins (cytochromes c of different origin, haemoglobin, myoglobin, ferredoxin and other non-haem iron proteins, cytochrome c oxidase, horseradish peroxidase) were recorded after fast changes in the active centre (electron reduction of iron, ligand dissociation). Strained states result in which the active centre has already been changed and undergone vibrational relaxation but the main part of protein globule is in the 'old', now out-of-equilibrium, state. Protein structure and chemical properties in these states differ considerably from those in equilibrium states. As a rule, the rate constants of protein-specific chemical reactions increase in out-of-equilibrium states by 1--3 orders of magnitude in comparison with those in equilibrium states. Spectra and reactivity of these proteins change in the course of slow (up to 10(-1) s) conformational relaxation, continuously approaching the equilibrium values. It seems that this conformational relaxation is essentially the elementary act of many enzymic reactions for which the rate of substrate-product transformation is determined by the rate of this conformational change.


Coenzyme-induced conformational changes and substrate binding in liver alcohol dehydrogenase. The apoenzyme and holoenzyme structures of liver alcohol dehydrogenase have been determined by X-ray methods to obtain details about coenzyme binding, substrate specificity and the catalytic mechanism. Coenzyme binding induces a conformational change of the protein which partly shields the active site from the solution. The reduced coenzyme binds in an open conformation similar to that of NAD bound to malate dehydrogenase. A hydrogen bond between Thr-178 and the carboxamide group of the coenzyme is essential for proper positioning of the nicotinamide in the active site. Coenzyme analogues in which the carboxamide group is absent or substituted with iodine bind in a different conformation and do not induce the structural change of the protein. Binding of substrate molecules has been studied in crystals obtained from an equilibrium mixture of enzyme, coenzyme and p-bromobenzyl alcohol. The oxygen atom of this substrate as well as that of the inhibitor molecules trifluoroethanol and dimethyl sulphoxide bind directly to the catalytic zinc atom. The substrate-binding region is a deep hydrophobic pocket at the bottom of which the zinc atom mediates electrophilic catalysis of alcohol oxidation.


The consequences of nucleotide binding to liver alcohol dehydrogenase. Extensive and informative steady-state kinetic investigations of the mechanisms of horse liver alcohol dehydrogenase have recently been complemented by observations of the fluorescence and spectroscopic characteristics of transient intermediates by rapid-reaction techniques. In this way it was possible to study separately steps involved during enzyme-substrate complex formation and during the catalytic process. It can be shown that a proton is liberated during complex formation before the transfer of a hydride ion from ethanol to form NADH. This must be due to a change in pK of a group on the enzyme protein and is linked to a change in tryptophan fluorescence. Pressure relaxation techniques have enabled us to study the rate constants of the change in tryptophan fluorescence linked to NAD+ binding and proton dissociation. We have shown that NAD+ binding occurs in two steps: a rapid secondorder association, followed by the substrate-induced isomerization to form the reactive enzyme-substrate intermediate. The isomerization rate constants were determined in both directions and their role in the overall reaction mechanism could be identified.


Uptake, distribution, and elimination of sodium linear alkylbenzene sulfonate and sodium alkyl sulfate in carp. Uptake, distribution, and elimination of labeled surfactants, 35S-labeled sodium laurylbenzenesulfonate (35S-C12-LAS) and 35S-labeled sodium lauryl sulfate (35S-C12-AS), were investigated in carp exposed to a low concentration level of the respective solutions found in river water in Japan by whole-body autoradiography and liquid scintillation counting. Whole-body autoradiograms showed that the fish absorbed 35S-C12-LAS and 35S-C12-AS from the solutions principally through gills and that the surfactants absorbed were rapidly distributed throughout the body tissues and organs. High concentrations were found in gills, blood, hepatopancreas, kidney, and gall bladder. The elimination in the fish that were kept in clean fresh water after exposure were relatively rapid in most tissues and organs except for gall bladder. These results suggest that the surfactants absorbed in fish may have an adverse effect on many tissues and organs of fish. What influenced the distribution profile and concentration factors of the surfactants in tissues and organs of carp were the exposure time and the molecular structure of the surfactants.


[Effect of ionizing radiation on cerebral phosphodiesterase]. The authors examined the influence of x-ray irradiation on phosphodiesterase system in the brain of rats and the sensitivity of the enzyme to inhibitors (caffeine, theophyline, thyopental) and activators (imidozol). The animals (Wistar with weights of 150--200 gm/were irradiated singly with a dose of 737 r. Phosphodiesterase activity (PD) was determined by the method of Filburn and Carn (1972) at two substrate concentrations (1 and 100 microM). X-ray irradiation did not change PD with high Km, while the enzyme with low Km was reduced significantly and transitionaly. Caffeine, theophyline and thyopental inhibited more PD with low Km in the irradiated rats in comparison with the control nonirradiated rats. The activating effect of imidazol on PD with low Km was more marked in irradiated rats. These data could be interpreted in the light of the molecular mechanisms, determining the altered action of some drugs after x-ray irradiation.


Decreased serum cholesterol-binding reserve in diabetes mellitus. Serum cholesterol-binding reserve (SCBR), the capacity of a serum sample to solubilize additional cholesterol in excess of its cholesterol content, was measured in 43 white male patients with maturity-onset diabetes in the age range of 35--59 years who were under treatment with insulin. The values were compared with those of 194 nondiabetic controls of the same race, sex, and age range. The mean +/- S.D. of SCBR of patients (71.9 +/- 29.3 mg./dl.) was lower than that of controls (88.9 +/- 30.9 mg./dl.) (p less than 0.001). Age in the range of 35 to 59 years had no correlation with SCBR in either patients or controls. SCBR was positively correlated with serum levels of cholesterol (SC) and triglycerides (TG) in both patients and controls. After adjustment for SC and TG, the difference in SCBR between patients and controls persisted (p less than 0.001). In 15 of 20 (75 per cent) patient-control pairs matched for SC and TG to within 5 per cent, the patient had lower SCBR (paired t-test, p less than 0.002). In 16 patients without elevation of serum lipid levels (SC below 250 and TG below 150 mg./dl.), the mean +/- S.D. of SCBR (59.1 +/- 17.7 mg./dl.) was lower than that of 49 controls having serum lipids in the same range (77.4 +/- 31.7 mg./dl.) (p less than 0.03). These results indicate an association of decreased SCBR with diabetes and are consistent with the hypothesis that low SCBR is associated with accelerated atherosclerosis and enhanced risk for coronary heart disease.


Nucleoside triphosphatase from the hen's egg white and vitelline membrane: purification, properties and relation to similar enzymes from the oviduct. Hen's egg white and vitelline membrane nucleoside triphosphatases were purified resulting in active soluble subunits with MR 260,000 +/- 10,000. PH optima are divalent cation dependent and situated at pH 6.2 and 8.0 with ATP and at pH 6.15 with ADP as substrate. Ca2+ and Mg2+ are activators. Km and Ki values for Pi and PPi were determined. The enzymes are specific neither for ATP nor for ADP alone. No separation between nucleoside triphosphatase and nucleoside diphosphatase could be achieved. Differences found in their action can be due to differences in organization and properties of the (intermediary) enzyme-substrate complexes. A close relationship exists with homologous enzymes found in oviductal secretory cells and in oviductal secretions.


Nucleotide sequence of the simian virus 40 Hind II + III restriction fragment J and the total amino acid sequence of the major structural protein VP1. The HindII + III restriction fragment J (Hind-J) represents 4.58% of the simian virus 40 genome. The information present in Hind-J is expressed as part of the major, late 16-S messenger RNA, which codes for the structural protein VP1. The nucleotide sequence of the 240-base-pairs-long Hind fragment J has been determined by analysis of each oligonucleotide from both strands resulting from T1 or pancreatic RNase digestion of RNA transcribed from the DNA and from RNase digestion of ribo-substituted DNA. Large oligonucleotide blocks which could be constructed mainly on the basis of complementarity were subsequently ordered by partial chemical degradation of terminally labeled DNA. This direct DNA sequencing approach also completely confirmed the results obtained by both aforementioned RNase degradation methods. In the strand with the same polarity as the late mRNA, triplets corresponding to termination codons are present in two of the three reading frames. The one open reading frame connects in phase with the open reading frame of the neighboring HindII/ III fragments K, F and G, which have been published previously and which together with Hind-J span the total VP1 gene. Some features of the primary nucleotide sequence of this VP1 gene and the derived VP1 amino acid sequence are discussed.


Biogenesis of cytochrome c in Neurospora crassa. Synthesis of apocytochrome c, transfer to mitochondria and conversion to Holocytochrome c. 1. Precipitating antibodies specific for apocytochrome c and holocytochrome c, respectively, were employed to study synthesis and intracellular transport of cytochrome c in Neurospora in vitro. 2. Apocytochrome c as well as holocytochrome c were found to be synthesized in a cell-free homogenate. A precursor product relationship between the two components is suggested by kinetic experiments. 3. Apocytochrome c synthesized in vitro was found in the post-ribosomal fraction and not in the mitochondrial fraction, whereas holocytochrome c synthesized in vitro was mainly detected in the mitochondrial fraction. A precursor product relationship between postribosomal apocytochrome c and mitochondrial holocytochrome c is indicated by the labelling data. In the microsomal fraction both apocytochrome c and holocytochrome c were found in low amounts. Their labeling kinetics do not subbest a precursor role of microsomal apocytochrome c or holocytochrome c. 4. Formation of holocytochrome c from apocytochrome c was observed when postribosomal supernatant containing apocytochrome c synthesized in vitro was incubated with isolated mitochondria, but not when incubated in the absence of mitochondria. The cytochrome c formed under these conditions was detected in the mitochondria. 5. Conversion of labelled apocytochrome c synthesized in vitro to holocytochrome c during incubation of a postribosomal supernatant with isolated mitochondria was inhibited when excess isolated apocytochrome c, but not when holocytochrome c was added. 6. The data presented are interpreted to show that apocytochrome c is synthesized on cytoplasmic ribosomes and released into the supernatant. It is suggested that apocytochrome c migrates to the inner mitochondrial membrane, where the heme group is covalently linked to the apoprotein. The hypothesis is put forward that the concomitant change in conformation leads to trapping of holocytochrome c in the membrane. The problems of permeability of the outer mitochondrial membrane to apocytochrome c and the site and nature of the reaction by which the heme group is linked to the apoprotein are discussed.


Native and latent forms of liver phosphorylase phosphatase. The non-identity of native phosphorylase phosphatase and synthase phosphatase. The directly measurable (native) phosphorylase phosphatase present in a fresh mouse liver extract is bound to particulate glycogen and is not inhibited by heat-stable inhibitors. Treatment of the extract with trypsin or ethanol at room temperature caused a more than 10-fold increase in phosphorylase phosphatase activity. This increased activity stems from the activation of completely inactive (latent) enzyme, the major part of which is present in the high-speed supernatant. The trypsin-revealed activity can be completely blocked by heat-stable inhibitors. Treatment of the animal with glucocorticoids increases, and fasting decreases the activity of the native phosphorylase phosphatase. The level of latent enzyme, however, is unaffected by these treatments. The major portion of synthase phosphatase in the fresh liver extract is bound to glycogen. This enzyme is inhibited by the heat-stable inhibitor-2 and inactivated by trypsin or ethanol as well as by several treatments that have little effect on phosphorylase phosphatase. Upon DEAE-cellulose chromatography at 0 degrees C of a fresh liver extract, phosphorylase phosphatase and synthase phosphatase were resolved as separate, single peaks. If the preparation was not kept at 0 degrees C during the entire procedure, two peaks of each enzyme were observed. Under these conditions the first peak of phosphorylase phosphatase and of synthase phosphatase coincided. From these findings it is concluded that synthase phosphatase and phosphorylase phosphatase, in their native form, are distinct enzymes.


A new method of chemical modification of N6-amino group in adenine nucleotides with formaldehyde and a thiol and its application to preparing immobilized ADP and ATP. Reaction of AMP with formaldehyde and 3-mercaptopropionic acid at pH 11.7 gave a new AMP derivative, N6-[(2-carboxyethyl)thiomethyl]-AMP (I) in 91% yield and reaction at pH 3.1 gave another new derivative, N6,N6-bis[(2-carboxyethyl)thiomethyl]-AMP (II) in 57% yield. The structures were determined by their 13C and 1H nuclear magnetic resonance spectra coupled with those of the simple analogues, N6-[(2-carboxyethyl)thiomethyl]-9-methyladenine (III) and N6,N6-bis[(2-carboxyethyl)thiomethyl]-9-methyladenine (IV) which were synthesized from 9-methyladenine in the same way as for derivatives I and II. ADP and ATP were treated in the same way as AMP to afford the corresponding carboxyl derivatives, N6-[(2-carboxyethyl)thiomethyl]-ADP (V), N6-[(2-carboxyethyl)thiomethyl]-ATP (VI), N6,N6-bis[(2-carboxyethyl)thiomethyl]-ADP (X) and N6,N6-bis[(2-carboxyethyl)thiomethyl]-ATP (XI) in 71%, 75%, 53% and 40% yield, respectively. These compounds were coupled to 1,3-diaminopropane with a water-soluble carbodiimide to give the corresponding amino derivatives, N6-([N-3-aminopropyl)carbamoylethyl]thiomethyl)-ADP (VIII), N6-(N-(3-aminopropyl)carbamoylethyl]thiomethyl)-ATP (IX), N6,N6-bis([N-(3-aminopropyl)carbamoylethyl]thiomethyl)-ADP (XIII), and N6,N6-bis([N-(3-aminopropyl)carbamoylethyl]thiomethyl)-ATP (XIV), which were further bound to CNBr-activated dextran to give new polymer-bound derivatives of ADP and ATP. These free and bo-nd derivatives were tested for their coenzymic activities against several kinases. The activities of the ADP derivatives, V, VIII, X, XIII, dextran-bound VIII, and dextran-bound XIII against acetate kinase were 82%, 81%, 68%, 55%, 35%, and 15%, respectively, relative to ADP and those of the ATP derivatives, VI, IX, XI, XIV, dextran-bound IX, and dextran-bound XIV against hexokinase were 88%, 94%, 60%, 81%, 58%, and 49%, respectively, relative to ATP.


N-(2-Oxoacyl)amino acids and nitriles as final products of dipeptide chlorination mediated by the myeloperoxidase/H2O2/Cl- system. The chlorination of dipeptides by the myeloperoxidase/H2O2/Cl- system takes place at the N-terminal amino group, whereas no chlorination of the amide nitrogen of the peptide bond can be observed. The N-terminal amino group is chlorinated to N-monochloroamine or/and N-dichloroamine. N-Monochloropeptides were the main products at higher pH values, at lower pH at mixture of N-monochloropeptides and N-dichloropeptides was formed owing to the dismutation of N-monochloroamine to N-dichloroamine. N-Monochloropeptides decompose, yielding NH3 and the corresponding N-(2-oxoacyl)amino acids. N-Dichlorodipeptides decompose faster but to nitriles and the free C-terminal amino acids. N-Dichloroglycyl-amino acid decomposes through a relatively stable intermediate (cyano-formylamino acid) to hydrogen cyanide, cyanogen chloride and the free C-terminal amino acid. Insulin chlorination also yields N-terminal glycyl and phenylalanyl N-monochloro derivatives, which deaminate to glyoxylyl and phenylpyruvyl residues.


Pre and post axial polysyndactyly, microcephaly and ptosis. A five-year-old boy of Iranian origin with multiple anomalies is described. His parents are first and second cousins. He presented with short stature, psychomotor retardation, microcephaly, ptosis, dacryostenosis, partial left nerve deafness, high arched palate, bifid uvula, total fusion between incisors, asymmetric preaxial and postaxial polysyndactyly, brachyphalangy, kyphosis and spina bifida occulta of S1. To our knowledge, a similar case has not been reported previously.


Facilitation of cardiac sympathetic function by angiotensin II: role of presynaptic angiotensin receptors. Intravenous infusion of two separate doses of angiotensin II in pentobarbital-anesthetized, desipramine-treated animals produced dose-related increases in arterial blood pressure and caused significant potentiation of the cardioacceleration observed during the stimulation of the right postganglionic cardiac sympathetic nerve fibers. Positive chronotropic effects of intravenous norepinephrine were not altered during angiotensin II infusion. Prior administration of Saralasin, an angiotensin receptor antagonist, caused significant attenuation of the pressor action of angiotensin II, and also significantly antagonized the facilitatory effect of angiotensin II on sympathetic transmission to the myocardium. These results suggest that angiotensin II can cause facilitation of sympathetic nerve function to the myocardium via an action on angiotensin receptors which may be located on sympathetic nerve terminals.


Pharmacological actions of HS-6, an oxime, on the neuromuscular junction. The effect of HS-6 [1-(2-hydroxyiminomethylpyridinium)-1-(3-carboxamidopyridinium)-dimethyl ether] on neuromuscular (NM) transmission was investigated using chick biventer cervicis (CBC), rat diaphragm (RD) and guinea pig ileum longitudinal muscle strip (GPLS) preparations. In the CBC preparation HS-6 did not cause a contraction, whereas it produced a dose-related contraction of the GPLS preparation. HS-6 produced a hemicholinium-like NM blockade in the CBC and RD preparations. This was supported by the fact that HS-6 inhibited choline uptake in erythrocytes. HS-6 inhibited the contractions of various nicotinic agonists in the CBC preparation and augmented the acetycholine contractions. The latter was due to AChE inhibition produced by HS-6.


Modification by lidocaine of the discharges of primary endings of muscle spindles in cat tenuissimus muscle. The effects of lidocaine (1--20 microgram/ml) on afferent discharge patterns of primary endings of muscle spindles in cat tenuissimus muscle were investigated. Discharge from the endings, recorded in Ia afferent axons, was evoked by ramp stretch of the muscle, stimulation of single static or dynamic fusimotor axons or by a combination of stretch and fusimotor stimulation. Spontaneous discharge of the endings at the initial length of the muscles was reduced by 2--5 microgram/ml and abolished by 10--15 microgram/ml lidocaine. The static but not the dynamic discharge elicited by muscle stretch was blocked by concentrations of 10--15 microgram/ml. The same concentrations abolished static and dynamic fusimotor influences on primary ending discharge. However, in one experiment where the spindle was microscopically observed, fusimotor stimulation still resulted in contraction of the intrafusal muscle even when fusimotor stimulation failed to elicit changes in discharge response patterns of the primary endings. These findings indicate that lidocaine interferes with the encoding mechanism prior to block of impulse conduction in either the fusimotor or afferent axons.


Cardenolide analogs. An explanation for the usual properties of AY 22241. AY 22241 (AY) was compared with digitoxigenin with respect to effects on myocardial contractility and inhibition of Na+, K+-ATPase. Ay was less potent than digitoxigenin but otherwise showed the same type of rapid onset and rapid reversal of activity usually associated with genins. Since AY is a glycoside, its behaviour was regarded as anomalous since glycosides usually show both slow onset and slow reversal of activity. Attempts were made to account for the genin-like properties of AY in terms of the model for the digitalis receptor proposed by Thomas et al. (1974a,b). It is suggested that the low potency and genin-like properties of AY may be due to the fact that the steroid is attached to the lactone through the carbon atom that is alpha to the carbonyl group. This feature could result in non-alignment of the sugar residue with the sugar binding site and might also reduce the effectiveness of the interaction of the steroid moiety with its binding site. A notable feature of AY toxicity was its extremely rapid progression to irreversible fibrillation.


The role of beta-adrenoceptors in coronary blood flow distribution in normal and ischemic canine myocardium. beta-Adrenoceptor agonists increase myocardial ischemic injury, mainly by elevating myocardial oxygen consumption. Moreover, it has been shown that isoprenaline may "steal" regional myocardial blood flow (RMBF) from ischemic to non ischemic areas and from epicardium to endocardium. The mechanisms of these two isoprenaline-induced redistributions of RMBF have been investigated by the use of radioactive microspheres in an experimental model of canine myocardial ischemia with simultaneous measurement of ST-segment elevation. Isoprenaline increased RMBF in both epi- and endocardial non ischemic areas and in epicardial ischemic areas, leading to a significant decrease in the endo/epi ratio. After atenolol, isoprenaline still increased RMBF but to a lesser extent and the endo/epi ratio was still decreased. Salbutamol, in doses inducing no significant changes in cardiac parameters or myocardial oxygen consumption, produced effects similar to those of isoprenaline. These results indicate a non-homogeneous beta2-stimulation-induced vasodilation in endo- and epicardium, which might be due either to the higher epicardial coronary vasocilatory reserve or to a heterogeneous distribution of transmural beta2-adrenoceptors. Isoprenaline also decreased the ischemic/non ischemic total blood flow ratio (I/NI) and caused further increases in ST-segment elevation. These effects were abolished by atenolol pretreatment, indicating the deleterious effects of isoprenaline-induced tachycardia in this I/NI decrease and in the ischemic injury.


Electrical coupling between primary afferents and amphibian motoneurons. The short-latency DR-EPSPs resistant to Ca2+-lack and to addition of Mn2+ and Mg2+ result from electrical coupling between primary afferents and spinal motoneurons in frogs and toads. There are two time constants by which the time constant for the decay of the electronic DR-EPSP can be described: 1. the membrane time constant which determines the rate of passive decay of the membrane potential shift produced directly by the presynaptic spike, 2. the rate at which the presynaptic after-depolarization (ADP) declines.  The latter value is very large as compared with the postsynaptic membrane time constant. Presynaptic tetanization does not change the magnitude of the initial spike-induced component of the EPSP but its later slowly decaying portion is potentiated markedly as a result of the post-tetanic increase in the amplitude of the ADP. The perfusion with substances blocking potential dependent potassium channels (4-AP and TEA) greatly augments the DR-EPSP due to prolongation of the presynaptic spike and appearance of multiple discharges in the presynaptic fibers. An antidromic electrical coupling between motoneurons and the terminals of primary afferents was demonstrated in the isolated amphibian spinal cord perfused with zero Ca2+, 2 mM Mn2+ solution containing TEA or 4-AP. Under these conditions ventral root volleys may evoke local graded depolarizing potentials in some sensory fibers. Such antidromic coupling potentials can reach the critical level for generating a single or multiple discharge.


Two types of electronic EPSP evoked in amphibian motoneurons by ventral root stimulation. Motoneurons of hemisected perfused frog spinal cord were used for intracellular recording of EPSP produced by ventral root stimulation. Two varieties of electrotonic VR-EPSP resistant to Ca-lack and to addition of 10 mM Mg2+ and 2 mM Mn2+ have been encountered. The early VR-EPSP started before the full somadendritic invasion and the time constant of their decay varied between 11 and 25 msec, mean 15.4 +/- 1.8 msec, i.e., it was significantly longer than the time constant of the motoneuronal membrane (2.6--6.9 msec, mean 4.4 +/- 0.5 msec). The late  VR-EPSPs appeared after a latent period which was significantly longer than that of an antidromic spike. They started after the full somadendritic invasion and had very rapid time course, the time constant of their decay approximated that of the motoneuronal membrane. The shape of the late VR-EPSP both before and after treatment with 4-AP of TEA which markedly facilitated its appearance resembled the shape of an antidromic spike, whereas this correlation was not found in the case of the early VR-EPSP. When the temperature was elevated above 18--19 degree C the late VR-EPSPs disappeared but the early VR-EPSPs still could be recorded. The available evidence suggests that the early VR-EPSPs are produced by direct synaptic interconnections between motoneurons and recurrent collaterals of the motor axons, and the VR-EPSPs are transmitted across dendrodendritic junctions.


Direct inhibitory synaptic linkage of pontomedullary reticular burst neurons with abducens motoneurons in the cat. 1. Unit spikes of burst neurons were extracellularly recorded in the pontomedullary reticular formation of the cat. These neurons were identified by their burst activity coincident with the quick inhibitory phase of the contralateral abducens nerve during vestibular nystagmus and their antidromic activation from the contralateral abducens nucleus. 2. When the extracellular field potentials in and near the abducens nucleus were triggered by spikes of a contralateral burs neuron, the averaged potential consisted of an early di- or triphasic spike and a late slow positive wave. The early spike was an action current caused by impulses conducting along the axon of the burst neuron. 3. The action potentials of a contralateral burst neuron. 3. The action potentials of a contralateral burst neuron were employed to trigger a post-spike average of the membrane potential of abducens motoneurons. Then unitary IPSPs with monosynaptic latencies were revealed. This provided direct evidence that the burst neurons are inhibitory in nature. The amplitudes of unitary IPSPs ranged from 18 to 220 mu V. Each inhibitory burst neuron branched widely in the abducens nucleus and was estimated to make inhibitory connections with approximately 60% of the motoneuron pool. 4. The post-spike average of compound potentials of the abducens nerve triggered by action potentials of contralateral single inhibitory burst neurons revealed inhibition of spike activity with latencies and time courses compatible with those of unitary IPSPs in motoneurons. The inhibition was observed with all inhibitory burst neurons tested.


Prominent excitatory pathways in the cat visual cortex (A 17 and A 18): a current source density analysis of electrically evoked potentials. The current source density (CSD) method in its one-dimensional approximation is used to analyze the field potentials in visual areas 18 and 17 of the cat, which were elicited by stimulating electrodes in the optic chiasm (OX), the optic radiation (OR) or in the respective cortical area itself. The CSD analysis reveals the basic pattern of excitatory postsynaptic activity. 1. In both visual areas the basic specific excitatory activity flows along three different intracortical pathways, all starting in layer IV: The first pathway relays activity from layer IV to supragranular pyramidal cells via strong, local connections to layer III and from there through long-distance connections to layer II. The second pathway conveys activity from layer IV to layer V, where it mainly contacts apical dendrites of layer VI pyramidal cells. This infragranular polysynaptic activity is not clearly resolvable into separate components, suggesting that it is conveyed by various groups of axons, among them long-distance horizontal connections. The third pathway has one synaptic relay within layer IV and then conveys activity to layer III. In addition, monosynaptic activity is revealed in layers VI and I. 2. In A 18 one coherent, fast-conducting group of afferents induces this basic activity pattern. In A 17 no such fast conducting input is resolvable; the supragranular activity is induced by a small group of afferents with intermediate conduction velocity, which terminate in the upper part of layer IV. The infragranular activity is induced by afferents with slower and widely scattered conduction velocities, which terminate in the lower part of layer IV. The layer VI input is very prominent in A 17 and also has a wide latency scatter. 3. The supragranular activity is more prominent in A 18 than in A 17 and the respective layers appear thicker, in accordance with anatomy. In A 17 the infragranular activity prevails and layers IV and VI appear very broad, again in accordance with anatomy. 4. Comparison of the CSDs with the original evoked potentials shows that the surface evoked potentials over A 18 reflect the three dipolar sink/source distributions of the coherent monosynaptic activity in layer IV and of the two prominent polysynaptic activities in layers III and II. The widely scattered activity in the lower part of layer IV in A 17 and all infragranular activities in both areas generate smaller, partly closed-field potentials; those are not discernible from the strong far-field potentials which originate from the supragranular activity and--especially in A 17--from farther distant events.


Afferent fibres from muscle receptors in the posterior nerve of the cat's knee joint. The properties of some receptors with afferent fibres in the cat's posterior knee joint nerve have been examined, especially those discharging tonically with the joint in intermediate positions between full flexion and extension. Some of these receptors behave like muscle spindles, and respond to manoeuvres which stretch popliteus muscle. Both in single unit and whole nerve recordings their discharge pauses during a popliteus twitch, and can be strikingly augmented by tetanic stimulation of a number of popliteus fusimotor fibres isolated from ventral root filaments. The action of succinylcholine on these receptors closely resembles its effect on popliteus spindle units with fibres sited normally in the popliteus nerve. Other units with properties suggesting origin from popliteus tendon organs were also observed; their fibres and those of the spindle units conducted at Group I velocity. It is concluded that some afferent fibres from popliteus spindles and possibly tendon organs commonly pursue an aberrant course in the posterior articular nerve of the knee joint.


Neuron-glia interactions: indirect effect of GABA on cultured glial cells. A study was made of the action of GABA on the membrane potentail and resistance of satellite glial (SG) cells in cultures of rat dorsal root ganglia. GABA (10(-4) M) depolarized all SG cells tested without producing significant changes in membrane resistance. Similar results were obtained from astrocytes of cultured rat spinal cord and brain stem, although only half of the cells tested were depolarized by GABA. Bicuculline (10(-5) and 10(-6) M) which blocked the GABA-depolarization on cultured dorsal root ganglion (DRG) neurons, also markedly reduced or blocked the action of GABA on SG cells. When GABA was tested in sodium-free bathing solution, the amino acid caused a depolarization of similar shape and amplitude as in normal (137 mM Na+) bathing fluid, indicating that uptake processes are probably not involved in producing the depolarization by GABA. It is suggested that the depolarizing action of GABA on glial cells is an indirect effect due to the release of potassium from adjacent neurons during the action of the amino acid.


The mole of pallido-thalamic transmission investigated with intracellular recording from cat thalamus. Pallido-thalamic transmission was studied by intracellular recording from neurons in the ventrolateral (VL) and ventroanterior (VA) nuclei of the thalamus in cats anesthetized with pentobarbital. Stimulation of the entopeduncular nucleus (ENT) produced short latency, inhibitory postsynaptic potentials in the VL-VA neurons (1.60 ms on average). When stimuli were applied closer to the VL-VA region along the pallido-thalamic pathway, i.e., to the rostral Forel's field, the IPSP latency was significantly reduced. Linear regression analysis of the IPSP latency against conduction distance between different stimulating the recording positions indicated that the IPSP was produced through a monosynaptic pathway at a conduction velocity of 5 to 11 m/s. The neurons which received IPSPs from the ENT distributed in the rostromedial VL and in the rostral VA, whereas relay cells responding only to the contralateral brachium conjunctivum were found in the caudal VL and in the dorsolateral portion of the rostral VL-VA complex. Reciprocal convergence of pallidal and cerebellar impulses were observed in only a small number of cells, which were located in the border between the two neuron groups. Recording of extracellular field potentials and focal stimulation within and around the rostral VL also indicated that the fiber potentials arose from the ENT nucleus and propagated along a bundle of fibers which terminated within the rostromedial VL-VA complex. These results are all explicable by assuming that the entopeduncular neurons are inhibitory in nature and so inhibit thalamic neurons monosynaptically.


The ventral spino-olivocerebellar system in the cat. V. Supraspinal control of spinal transmission. 1. The transmission from the flexor reflex afferents (FRA) and from tracts running in the ipsilateral half of the spinal cord to the spino-olivocerebellar paths ascending through the ventral funiculus (VF-SOCPs; Oscarsson and Sjölund, 1977) was compared with the transmission from these sources to segmental reflex arcs. The climbing fibre responses evoked in Purkinje cells by electrical stimulation of limb nerves and spinal tracts were monitored by recording the mass activity at the cerebellar surface simultaneously from several termination zones, while the activity in flexor motoneurones was recorded from a flexor nerve and the primary afferent depolarization from a dorsal filament. 2. Changes in the segmental reflex response were produced by release from the tonic inhibition of transmission from the FRA in decerebrate preparations and by conditioning electrical stimulation of dissected spinal funiculi containing inhibitory descending tracts. 3. The changes of the transmission from the FRA to two of the paths, the a- and b2-VF-SOCPs, parallelled the changes of the transmission to the segmental reflex arcs. On the other hand, the monosynaptic transmission from the FRA to the c1- and c3-VF-SOCPs was not significantly influenced by the inhibitory descending control systems. 4. The a- and b2-VF-SOCPs but not the c1- and c3-VF-SOCPs received polysynaptic excitation from tracts running in the ipsilateral half of the spinal cord. 5. The suggestion that the a- and b2-VF-SOCPs carry information related to interneuronal activity in segmental centres, whereas the c1- and c3-VF-SOCPs forward information mainly related to peripheral events (Andersson and Sjölund, 1978) is supported by the present findings.


Polysynaptic activation of the dentate gyrus of the hippocampal formation: an olfactory input via the lateral entorhinal cortex. The possibility that olfactory input is transmitted to specific subregions of the hippocampal formation via the entorhinal cortex was investigated electrophysiologically by analyzing the laminar profiles of potentials evoked in the hippocampal formation by stimulation of the lateral olfactory tract (LOT). LOT stimulation resulted in long latency (14--20 ms) evoked responses in the dentate gyrus of the hippocampal formation ipsilateral to the stimulation. The variable long latency of these responses and their inability to follow stimulus rates of 40/s suggested that these potentials reflected polysynaptic activation. Analysis of the laminar profiles of the evoked potentials indicated that the responses originated from a synaptic field localized in the outer portion of the stratum moleculare of the dentate gyrus, a terminal distribution which overlaps that of the lateral entorhinal cortical (LEC) projection to the dentate gyrus. Lesions of the LEC eliminated the long latency responses in the dentate gyrus evoked by LOT stimulation. In addition, a conditioning pulse delivered either to the LOT or to the LEC produced paired pulse potentiation of the response elicited by subsequent stimulation of the other structure. No evidence was found to indicate that responses were generated in regio superior of the hippocampus proper following LOT stimulation. Taken together, these results suggest that stimulation of the LOT activates the dentate gyrus of the hippocampal formation by multisynaptic pathways which relay through the lateral portion of the entorhinal area. This finding is discussed with regard to entorhinal cortical organization and the known olfactory projections to the LEC.


Direct excitation of neck motoneurons by interstitiospinal fibers. 1. Responses of neck motoneurons to stimulation of the interstitial nucleus of cajal (INC) were recorded intracellularly in cats under chloralose anesthesia. When stimuli were applied within or close to the INC, short latency, monosynaptic excitatory postsynaptic potentials (EPSPs) were evoked in many neck motoneurons. Such EPSPs were not evoked by stimulating mesencephalic regions outside the INC. 2. Stimulation of the ipsilateral INC produced monosynaptic EPSPs consistently in biventer cervicis-complexus (BCC) motoneurons, while such EPSPs were observed in about two thirds of the splenius (SP) motoneurons and half of the trapezius (TR) motoneurons tested. Stimulation of the contralateral INC produced weak monosynaptic EPSPs in about half the BCC motoneurons and in a few SP and TR motoneurons. All types of motoneurons also received longer latency, apparently polysynaptic, PSPs from both INCs. In BCC and TR motoneurons these were mainly EPSPs, in SP, mixed excitatory and inhibitory PSPs. 3. Monosynaptic EPSPs evoked by INC stimulation were not eliminated by acute and chronic parasagittal and transverse lesions placed to interrupt the bifurcating axons of all vestibulospinal and many reticulospinal neurons. No significant collision was observed between EPSPs evoked by INC and vestibular or reticular stimulation. The EPSPs evoked by stimulation of the INC therefore appear to have been produced by activation of interstitiospinal neurons rather than by an axon reflex mechanism. 4. The properties of a number of interstitiospinal neurons were observed while recording extracellularly from the mesencephalon to map the location of the INC. One third of the interstitiospinal neurons activated antidromically from the C4  segment could also be activated antidromically from L1. These lumbar-projecting neurons had conduction velocities ranging from 15--123 m/s. Several interstitiospinal neurons sending axons to the ventral horn of the neck segments were identified and two of these were found to be branching neurons that projected both to the neck and to lower levels of the spinal cord.


Effects of exogenous neuraminidase on unit activity in frog spinal cord and fish optic tectum. The effect of exogenous neuraminidase on spontaneous and evoked synaptic activity was investigated following injection of the enzyme into frog spinal cord and into cord and into the carp optic tectum. 1. Injection of enzyme into spinal cord segments caused a significant increase of motoneuron activity in the corresponding spinal nerve, which lasted for 7--31 min. 2. The amplitude of postsynaptic evoked potentials in the optic tectum was increased after neuraminidase injection up to 200% of control level for 20--40 min, whereas the amplitude of summed action potentials of retino-tectal afferents remained unchanged. 3. Similar effects were observed in single cell responses of the optic tectum with some differences in the degree of increase in activity, as well as latency and final depression of the stimulus response. 4. The extent of neuraminic acid liberation following neuraminidase treatment was determined biochemically. In both tissues investigated the amount of free neuraminic acid was increased significantly (4--5.5 fold) after enzyme treatment. Whereas after enzyme injection into spinal cord and optic tectum the percentage release of total glycoprotein- and glycolipidbound neuraminic acid was 12% and 15%, respectively, liberation from enzyme incubated tissue homogenates was somewhat higher (20.5% and 24%).


Mass fragmentographic determination of cholecalciferol and 25-hydroxycholecalciferol in human serum. The serum extracts were purified by column-, thin layer- and high pressure liquid chromatography. Deuterated cholecalciferol and deuterated 25-hydroxycholecalciferol were used in internal standards. The quantitative analysis was performed using GC-mass fragmentography technique of TMS-ethers.


Imbalance in the activities of alkaline phosphatase and Na+-K+-ATPase in the brain of experimentally induced phenylketonuric squirrels (Funambulus palmarum). Phenylketonuric squirrels have shown marked inhibition of alkaline phosphatase in the olfactory lobes and cerebral hemispheres, whereas the Na+-K+-ATPase remained less altered. In the pathogenesis of phenylketonuria inhibition of alkaline phosphatase at the level of "Blood-Brain Barrier" (BBB), leads transport system to impaired functioning.


Trichinella spiralis: acceleration and inhibition of cyst calcification in rats. Daily administration of vitamin D3 (75,000 IU/kg b. wt) for 7 days accelerated Trichinella spiralis cyst calcification in rats with a 14-week-old infection. When disodium ethane-1-hydroxy-1, 1-diphosphonate (EHDP) was administered (50 mg/kg b. wt) from 2 days before until 2 days after vitamin D3 treatment, cyst calcification was inhibited. Thus, the ability to inhibit E. spiralis calcification has demonstrated for the first time.


Effect of sodium butyrate in combination with prostaglandin E1 and inhibitors of cyclic nucleotide phosphodiesterase on human amelanotic melanoma cells in culture. Sodium butyrate and cyclic AMP-stimulating agents (prostaglandin E1, papaverine, theophylline, and RO20-1724) caused reductions in the cell number (primarily due to reduction in cell division) when added individually to human melanoma cells in culture. However, the combination of sodium butyrate with one of the cyclic AMP-stimulating agents produced a marked reduction in cell number (primarily due to cell death).


[Isolation by affinity chromatography of specialized membrane fractions from cat liver microsomes]. Microsomal glucokinase is solubilized by incubation in the presence of several metabolites. After solubilization of the enzymes, the membranes present free sites for specific binding of glucokinase, therefore, they can be purified by affinity chromatography on Sepharose--ATP-glucokinase. This method yields membranous vesicles which contain, in addition to glucokinase, uridylyl-transferase, phosphoglucomutase, sialyl-transferase and adenylate cyclase. Galactosyl-transferase, glucose-6-phosphatase and NADPH cytochrome c reductase are absent. It appears that functionally related enzyme from UDP-glucose biosynthesis are aggregated onto specific patches of the membrane, most likely from Golgi apparatus.


Central mechanisms of fever.

Central mechanisms of fever. The possible role of various potential chemical mediators in the production of fever is reviewed. A major problem in this field is the very considerable conflict of evidence, let alone interpretation. On the existing evidence, it appears unlikely that monoamines, acetyl choline, or alterations in relative concentrations of sodium and calcium play any major role in the production of fever. Recent evidence makes it unlikely that prostaglandins have a direct role in this mechanism, though the involvement of other metabolites of arachidonic acid has not been excluded. It is possible that protein synthesis may play a part in the central action of leukocyte pyrogen.


The role of prostacyclin in vascular tissue. Prostacyclin (PGI2) generated by the vascular wall is a potent vasodilator, and the most potent endogenous inhibitor of platelet aggregation so far discovered. Prostacyclin inhibits platelet aggregation by increasing cyclic AMP levels. Prostacyclin is a circulating hormone continually released by the lungs into the arterial circulation. Circulating platelets are, therefore, subjected constantly to prostacyclin stimulation and it is via this mechanism that platelet aggregability in vivo is controlled. Moreover, phosphodiesterase inhibitors such as dipyridamole or theophylline exert their antithrombotic actions by potentiating circulating prostacyclin. The prostacyclin:thromboxane A2 ratio is important in the control of thrombus formation; manipulation of this ratio by small doses of aspirin (which will inhibit mainly platelet cyclooxygenase), a selective inhibitor of thromboxane formation, or the dietary use of a fatty acid like eicosapentaenoic acid (which would be the precursor for a delta17-prostacyclin (PGI3) but is transformed by the platelets into nonaggregating thromboxane A3) might have beneficial effects as antithrombotic therapies. Prostacyclin has interesting potential for clinical application in conditions where enhanced platelet aggregation is involved or to increase biocompatibility of extracorporeal circulation systems.


[Effect of hirudin on hormonally caused activation of nonenzymatic fibrinolysis in immobilization stress]. The specific inhibitor of thrombin-hirudin was used for studying the mechanism of activating effect of ACTH and adrenaline upon the unenzymatic fibrinolysis (UEF), the latter characterizing the function of the anticoagulating system (ACS). Simultaneous administration of ACTH and hirudin to animals subjected to the immobilization stress did not reduce the effect of ACTH upon UEF, while simultaneous administration of adrenaline and hirudin revealed a diminished effect of the former. This suggests different mechanisms of ACTH and adrenaline effects upon UEF: the stimulating effect of noradrenaline is realized through thrombinogenesis followed by activation of the ACS function and by an increase of UEF and therefore inhibitable by hirudin which form an inactive complex with thrombin. While the stimulating effect of ACTH upon UEF is exerted, apparently, not through thrombinogenesis and hence is valid even in presence of hirudin. Hirudin proper exerts no effect upon UEF.


[Interorgan metabolic correlations during muscular activity and fatigue]. Biochemical and mathematical analysis revealed that metabolic processes in muscles, blood, liver, and brain during both unfatiguing muscular activity and in fatigue change their correlative bonds not identealby. The experiments exposed as a common traits, as differences in metabolic structure of both rapidly and slowly developed fatigue.


The influence of Triton X-100 on the nuclear envelope of the isolated liver cell nuclei. In order to obtain more precise information on an eventual presence of extra-membranous lipids in the interior of the nucleus, the effects of Triton X-100 on the lipid content and ultrastructure of isolated rat liver nuclei was investigated. Enzyme markers (a.o. glucose-6-phosphatase) were used to control impurities of the nuclear fractions biochemically along with transmission electron microscopy and qualitative and quantitative light microscopy to check the condition of the nuclei obtained. Treatment of the nuclear fraction with increasing concentrations of Triton X-100 resulted in a decrease of the phospholipid content down to 25% at a Triton X-100/protein ratio of 0.4. A further decrease to 8% was measured at a ratio of 1.5. Electron microscopy of nuclei of the latter group showed nuclei containing outer membrane fragments in 2.5% of their surfaces. The composition of lipids extracted from a nuclear fraction appeared to be markedly changed after treatment with Triton X-100 with an increase of the percentage of neutral lipids and the phospholipids diphosphatidyl-glycerol and spingomyelin. From the chemical and morphological data obtained, the conclusion was drawn that a substantial part of the lipids remaining in the isolated nuclei after treatment with Triton X-100 is localized in both membranes of the nuclear envelope. It cannot however, be excluded that a small portion would be present in the interior of the nuclei.


Visualization of mouse DNA transcriptional complexes in mouse kidney cells infected with SV 40 virus. Electron microscopic studies of transcribed cellular deoxynucleoprotein (DNP) fibers from mouse kidney cells abortively infected with Simian Virus 40 (SV 40) revealed two types of transcriptional complexes. Tandemly repeating units representing ribosomal transcriptional events, although few in number because of the procedure employed, clearly confirmed results of other techniques which revealed the unusually long length of the untranscribed spacer intercepts in mouse nucleolar chromatin. In non-nucleolar arrays the density of the ribonucleoprotein (RNP) fibrils varied, as did the length and configuration of the associated DNP fibers. A statistical correlation between a "smooth" appearance of a transcribed portion of a DNP fiber and a high density of nascent RNP fibrils was observed.


Plasma cyclic AMP response to glucagon as an index of tissue responsiveness to thyroid hormone. The rise in plasma cyclic AMP after glucagon has been studied in hyper- and hypothyroid patients before and after treatment. In the hyperthyroid group, each individual patient showed a decrease in cyclic AMP response to glucagon on becoming euthyroid, but there was no change after treatment with propranolol. In the hypothyroid group, each individual patient showed an increase in response on becoming euthyroid on thyroxine. We suggest that peak plasma cyclic AMP response to glucagon could be used to monitor tissue responisveness to thyroid hormone during treatment of hypo- and hyperthyroidism, though change in this response is a more sensitive indicator of change from the hypothyroid to the euthyroid state than from the hyperthyroid to the euthyroid state.


[Pancreatic polypeptide (author's transl)]. Pancreatic Polypeptide (PP) was first described in birds by Kimmel et al. (1968). It was later isolated from the pancreas of several mammalian species by Chance and Jones (1974). It has been demonstrated in the islets of many animal species by immunocytochemical methods. PP levels are assayable in plasma and rise sharply after food intake. The pharmacological properties and physiological role of PP are still ill defined. It appears to have a spectrum of actions peculiar to each species. Recent research on this subject is reviewed in this article. High levels of circulating PP have been demonstrated in juvenile and maturity-onset diabetics, as well as in some patients with islet cell tumors. However no definite clinical syndrome due to hypersecretion of PP as been identified as yet. It remains a matter of speculation that a deficiency of PP might be responsible for some types of obesity. PP-cells are rare in the pancreas of healthy young individuals. Hyperplasia of PP-cells has been observed in a wide variety of pathological conditions, but is most prominent in the pancreas of chronic insulin dependent diabetics. Histologic evidence strongly suggests that PP-cell hyperplasia represents an atypical form of islet regeneration. It is always focal in distribution and is most remarkable in those lobules that have lost the capacity to reproduce islets of normal cytologic composition.


Influence of bromoergocryptine on estrogen-modulated prolactin receptors of mouse mammary gland. Modulation of specific binding of prolactin to murine mammary gland as a response to treatment with various doses of estradiol benzoate (EB) was studied. Measurements of serum and pituitary levels of prolactin were also carried out simultaneously. Estradiol benzoate at a dose of 5 microgram significantly increased the binding of 125I-labelled rat prolactin (rPRL) to mammary gland concomitant with increased serum prolactin levels in ovariectomized mice. Administration of bromoergocryptine along with EB resulted in decreased serum prolactin levels as well as binding of prolactin to breast tissue. It thus appears that the influence of estradiol on binding of prolactin to mammary gland is mediated primarily via its property of enhancing serum prolactin concentration apart from its possible direct effect at the target tissue level.


On the role of protein synthesis in the response of adrenal tumor cells to ACTH. Y-1 adrenal tumor cells were incubated with aminoglutethimide with and without ACTH. Greater production of pregnenolone from endogenous cholesterol was observed (after washing to remove aminoglutethimide) in mitochondria from cells incubated with aminoglutethimide and ACTH than in those from cells incubated with aminoglutethimide alone. This response was inhibited by cycloheximide and puromycin but not by chloramphenicol or actinomycin D. ACTH increased the incorporation of [3H]tyrosine into protein associated with mitochondria but not into total cell protein or protein of postmitochondrial supernatant. This response did not require aminoglutethemide block and was inhibited by cycloheximide and puromycin but not by chloramphenicol or actinomycin D. Dibutyryl cyclic AMP produced both of these responses (increased production of pregnenolone and synthesis of protein associated with mitochondria). The concentration of cycloheximide required to cause 50% inhibition of the responses to ACTH and dibutyryl cyclic AMP was approximately the same for steroidogenesis by whole cells, for production of pregnenolone by isolated mitochondria, for incorporation of [3H]tyrosine into Y-1 cell protein and for the increase in synthesis of protein associated with mitochondria produced by ACTH (0.08--0.2 microgram/ml). Disc gel electrophoresis revealed that the increased incorporation of [3H]tyrosine involved two proteins corresponding to molecular weight of approximately 27,000 and 13,000 respectively. These observations suggest that ACTH promotes synthesis of protein(s) by cytoplasmic ribosomes on stable messenger RNA, that the protein(s) becomes associated with mitochondria and that the protein(s) includes one or more which are associated with the increase in production of pregnenolone produced in mitochondria by the addition of ACTH to adrenal cells.


Occupancy of aldosterone binding sites in rat kidney cytosol. The binding sites for aldosterone and a potent aldosterone antagonist (SC-26304) were studied in kidney cytosol from adrenalectomized rats. Preformed cytosol and kidney slices were incubated with 3H-labeled steroids in a wide range of concentrations. The recovery and characteristics of the binding sites were affected by the incubation and homogenization conditions. High-affinity, Type I mineralocorticoid binding was reduced by more than 95% when cytosol was incubated at 25 degrees C in the presence of calcium. Tissue dilution also affected the binding sites. SC-26304 was bound to high- and low-affinity receptors, similar to the binding of aldosterone. The physiologic response to aldosterone could result from binding to either or both sets of sites. Some of the physiologic responses to spirolactones could represent antagonism of the binding of aldosterone to either or both sites. A convenient method is presented for describing the relative occupancy of several different sites by any particular steroid.


Mucosal enzyme patterns in gastric epithelial disease. A correlation was sought between changes in enzymes involved in gastric acid secretion (Mg-, NaK-, K- and HCO3-stimulated ATPases) and histological changes in gastric biopsies. Alkaline phosphatase was also studied. Mg- and NaK-stimulated ATPase activities increased significantly in biopsies from the pylorus and antrum which showed moderate or severe gastritis. NaK ATPase levels increased and HCO3 ATPase decreased in incisural, body and fundic mucosa which had intestinal metaplasia and atrophic gastritis. No K+ ATPase was found in normal mucosa. The total activity of alkaline phosphatase did not vary with histological changes in the gastric mucosa. Results indicate that the ATPase enzyme systems are sensitive indicators of gastric mucosal disease.


The influence of the major histocompatibility complex (H-2) on experimental diabetes in mice. Mice with different histocompatibility loci on an identical background genome (congenic resistant lines of mice) were used to study the possible influence of the histocompatibility complex on experimental diabetes. The major histocompatibility complex (H-2) was not found to influence the diabetogenic effect of encephalomyocarditis (EMC) virus. In contrast the glucose intolerance following heterologous and homologous immunization with pancreatic antigens appeared H-2 influenced. Antibodies against cell surface components on viable B-cells were present in serum from mice with glucose intolerance induced by homologous immunization. The results suggest that the susceptibility to experimental autoimmune diabetes in mice is influenced by the H-2 complex.


Effects of alloxan on glucose-stimulated insulin secretion, glucose metabolism, and cyclic adenosine 3', 5'-monophosphate levels in rat isolated islets of langerhans. Insulin secretion was stimulated and cyclic adenosine 3', 5'-monophosphate (cAMP) levels were elevated in isolated rat islets by 27.5 mmol/l glucose. Alloxan caused a dose-dependent decrease in both variables with complete obliteration of insulin release at a concentration of 1.25 mmol/l. D-glucose, in the presence or absence of extracellular calcium, or 3-0-methyl-D-glucose (both at 27.5 mmol/l) protected completely against the effects of alloxan on both glucose-induced insulin release and cAMP Levels. 3-0-Methylglucose did not stimulate insulin secretion or elevate cAMP and did not interfere with glucose-stimulated secretion or elevation of cAMP. When glucose-stimulated insulin release was abolished by alloxan, the metabolism of glucose, determined by the rate of 3H2O formation from [5-3H] glucose, was depressed by 20%. It is concluded that alloxan altered the adenylate cyclase system such that it could no longer be stimulated by glucose. Glucose-stimulated insulin secretion or elevation of cAMP did not appear essential for glucose to protect against alloxan. Protection by 3-0-methylglucose did not appear to be mediated through an alteration of cAMP metabolism. Alloxan did not inhibit glucose-induced insulin secretion by grossly altering glycolysis.


Changes in intramembranous particle topography and concanavalin A receptor mobility associated with myoblast differentiation. These studies have examined the distribution of plasma membrane intramembranous particles (PMP) visualized by freeze fracture and concanavalin A receptors seen by ultrastructural cytochemistry of differentiated and undifferentiated L6 myoblasts. Undifferentiated mononucleated cells have a clustered distribution of PMP on the majority of the fracture faces. Associated with cell differentiation and cell fusion a more uniform distribution of PMP is observed. Changes also occur with myoblast differentiation in the topography and dynamics of receptors bound to concanavalin A. If undifferentiated or differentiated cells are fixed with glutaraldehyde and then reacted with con-A a uniform distribution of con-A is seen on the cell surfaces. In contrast to this if unfixed live cells are reacted at 37 degrees C with con-A a profound redistribution occurs on differentiated cells (greater than 99% showing redistribution) while receptors remain in a uniform array on undifferentiated cells (approximately 95% uniform distribution). In addition to the membrane binding, con-A is observed to bind to an extracellular filamentous matrix seen in high density undifferentiated cultures which then appears to be degraded with differentiation and myoblast fusion. These studies show that a number of membrane changes, both structural and dynamic occur with myoblast differentiation.


Clinical significance of mitochondrial glutamic-oxaloacetic transaminase in serum of patients with liver disease. Serum mitochondrial glutamic-oxaloacetic transaminase activity was determined in 83 patients with various liver diseases and 10 healthy adults. 1) The average of mitochondrial glutamic-oxaloacetic transaminase value was 1.2 mU in healthy adults, 8.3 mU in patients with acute hepatitis, 13.7 mU in patients with post-transfusion hepatitis, 5.0 mU in patients with persistent hepatitis, 4.5 mU in patients with chronic inactive hepatitis, 9.6 mU in patients with chronic active hepatitis, 5.6 mU in liver cirrhosis, and 295 mU in a patient with fulminant hepatitis. 2) While one patient with acute hepatitis showed the highest value in the group of 29 mU, one patient with fulminant hepatitis showed an extremely high value of 295 mU, revealing an obvious difference between them. 3) One patient with fresh myocardial infarction also showed an extremely high value of 110 mU.


Studies on the outbreak of hepatitis A in an institute for mentally retarded children. The authors encountered an outbreak of acute hepatitis in a public institute for mentally retarded children in Aomori Prefecture, Japan. Studies revealed that the probable vehicles of transmission of infection were contaminated water, contaminated meals, and close contact. From the clinical manifestations and epidemiological investigations of 41 affected children and staff members, an outbreak of hepatitis A was strongly suspected. Immune electron microscopy disclosed hepatitis A virus antigen particles in the stool specimens collected during the few days before and after peak transaminase elevation. Hepatitis A antigen was further extracted and purified. The antigen was the first reported recovery of the virus from a natural outbreak of hapatitis A in Asia. Subsequently, with the immune adherence hemagglutination test, using this extracted antigen, an increase in titer of antibody to hepatitis A antigen was demonstrated. Thus, this epidemic was serologically established as an outbreak of hepatitis A. Human immune serum globulin for the protection against hepatitis A was administrated to the 80 individuals concerned, and it was effective in preventing the clinical manifestation of hepatitis.


Serum ribonucleases in pancreatic cancer: relation to tumor histology. Serum Ribonuclease (RNase, EC. 3. 1. 4. 22) of normal persons and of patients with chronic pancreatitis, or pancreatic cancer was determined with poly (C) as substrate. Strikingly abnormal elevations occured in the serum RNase of patients with pancreatic cancer (p less than 0.001). Average serum RNase values of 18 normal persons, 10 patients with chronic pancreatitis and 26 patients with pancreatic cancer were 92, 118, and 249 units, respectively. In patients with pancreatic cancer, we compared the RNase level with four histologic types (ductar cell adenocarcinoma, anaplastic cell carcinoma, acinar cell carcinoma, and islet cell carcinoma). Adenocarcinoma showed higher activity than the other histologic types (p less than 0.005). When we compared the serum of pancreatic cancer and pancreatic cancer tumor extract with normal serum and normal pancreas extract, strikingly different phosphocellulose chromatographic pattern were evident. The correlation of increased serum RNase levels with tumor histology and different chromatographic pattern may explain the new enzyme production in cancer patients, and have biological significance in the development of pancreatic cancer.


Hepatocellular carcinoma in the U.S.A., etiologic considerations. Localization of hepatitis B antigens. The serologic and tissue markers of hepatitis B virus (HBV) were studied in 50 patients in whom hepatocellular carcinoma (HCC) was confirmed at autopsy. Serologic and tissue markers included serum hepatitis B surface antigen (HBsAg), tissue HBsAg, tissue hepatitis core antigen (HBcAg), and serum antibody to HBcAg (anti-HBc). Twenty-two patients had HCC arising in alcoholic cirrhosis; 2 of the 22 (9.1%) had one or more of the HBV tissue and serologic markers. This infection rate is similar to the rate of 7.9% observed in 63 control alcoholic cirrhotic patients without HCC. In contrast, 15 of 20 (75.0%) patients with HCC in nonalcoholic chronic active liver disease showed evidence of active HBV infection. One of 8 patients with HCC in normal liver had serum HBV markers. This result indicates that there is an extremely high prevalence of HBV infection among HCC patients with nonalcoholic chronic liver disease in the U.S.A. The prevalence of HBV infection in these patients is as high as that observed in Asia and Africa. Thus, it can be concluded that the lower prevalence rate of active HBV infection in HCC patients in the U.S.A. is the result of statistical dilution of HCC-B-viral disease by the large numbers of the alcoholic cirrhotic patients with HCC, and that if chronic active hepatitis type B were as common in the United States as it is in Africa and Asia, the frequency of occurrence of HCC might also be as high.


Antibodies to viral gastroenteritis viruses in Crohn's disease. Antibody prevalence and titer to rotavirus and Norwalk virus were studied in Crohn's disease patients and in age-, sex-, and time-matched controls. There were no significant antibody differences between the groups studied.


A simple method for identifying the palindromic sequences recognized by restriction endonucleases: the nucleotide sequence of the AvaII site. Tables specifying the frequencies, distances between and positions of all possible tetra-, penta- and hexanucleotide palindromes in phiX174 and SV40 viral DNAs were prepared by a computer search of their base sequences. A simple method based on these tables is described for identifying the sequence recognized by any specific restriction endonuclease. The method requires experimental determination of the number and approximate sizes of the fragments obtained by digestion of phiX174 RF and SV40 DNAs. Using this method we identified the sequence for AvaII restriction endonuclease as 5'-GG(AT)CC.


Hepatocellular carcinoma in Great Britain: influence of age, sex, HBsAg status, and aetiology of underlying cirrhosis. An analysis of 294 patients who died with cirrhosis showed that 24% had developed hepatocellular carcinoma. Haemochromatosis and HBsAg positive chronic active hepatitis were high risk groups (36% and 42% respectively) and the frequency was lowest in primary biliary cirrhosis and HBsAg negative chronic active hepatitis (3% and 11% respectively). Those with hepatocellular carcinoma showed a striking male preponderance (11:1) and further analysis has shown that the proportion developing this tumour in each group was closely related to the proportion of males in that group (r=0.97). Age was the only other significant factor, malignant change occurring more commonly in those over the age of 50 years than those below (30% and 7% respectively, P less than 0.005). The indluence of HBsAg was largely accounted for by the known predisposition of males to carry HBsAg. The group of patients who had developed this tumour without cirrhosis were younger (mean age 39 years) and had a lower male to female ratio of 1.1:1 and the place of contraceptive-related tumour within this group is dicussed.


[A method for percutaneous thin-needle biopsy of the pancreas aimed by ultrasound (author's transl)]. Percutaneous biopsy of the pancreas with a fine needle aimed by ultrasound was carried out on 26 patients with sonographically proven carcinoma of the pancreas. The accuracy of this method was correlated with other radiological techniques. Needle biopsy of the pancreas proved an informative and economical procedure, since the sonographic demonstration of a pancreatic mass otherwise requires additional radiological and endoscopic investigations.


[Genetic and biologic aspects of schizophrenias]. The results of investigations into the causes of schizophrenia--especially twin studies and adoption studies--support a genetic component to the transmission of schizophrenia. The exact mode of inheritance is still unknown. That what is inherited is probably a general tendency or disposition to psychopathology. Factors in the environment then elicit these tendencies or dispositions. The results of the biochemical investigations of schizophrenia and the consistent antidopamine effect of all antipsychotic agents support the idea that the dopamine synaptic neurotransmission may play an important role in the pathophysiology of schizophrenia.


Participation of L-ascorbate:ferricytochrome b5 oxidoreductase in ascorbate-dependent fatty acid desaturation of rat liver microsomes. The microsomal enzyme ascorbate-cytochrome b5 reductase participates in the ascorbate-dependent fatty acid desaturation. Three pieces of evidence are given for this statement: 1) Comparison of the rate of ascorbate-dependent oleate formation with the rate of reduction of cytochrome b5 in microsomes and in the isolated detergent form shows that only the enzymatic reduction of cytochrome b5 is fast enough to support oleate formation; 2) added enriched ascorbate-cytochrome b5 reductase increases the rate of return of stearoyl-CoA oxidised cytochrome b5 back to the reduced state; 3) addition of enriched ascorbate-cytochrome b5 reductase increases the rate of ascorbate-dependent oleate formation in rat liver microsomes.


Increase of the gluconeogenic and decrease of the glycolytic capacity of rat liver with a change of the metabolic zonation after partial hepatectomy. During the first 72 h after 67% partial hepatectomy of female Wistar rats (160 g) the specific activities [mumol X min-1 X (g liver)-1] of the glucogenic glucose-6-phosphatase and fructose-bisphosphatase and of the glycolytic hexokinase and 6-phosphofructokinase remained essentially constant. However, the activity of the glycolytic pyruvate kinase (L- plus M2-type) was decreased slightly and that of glucokinase was decreased markedly to below 30%, while the glucogenic phosphoenolpyruvate carboxykinase was increased to over 200%. Between 10 and 40 h after partial hepatectomy, when the proliferation started in the periportal area, a shift of the glucogenic glucose-6-phosphatase-rich zone from its normal periportal to an intermediate or even perivenous position was observed histochemically. After 48 h, when the proliferation was no longer restricted to the periportal zone, the normal glucose-6-phosphatase zonation (as before partial hepatectomy) was restored. Glycogen was degraded rapidly during the first 4 h after operation; it was later repeatedly resynthesized and degraded in correlation with the feeding rhythm of the animals. The zonation of glycogen metabolism was in accord with the observed zonation of glucose-6-phosphatase.


Morphology and immunohistochemically-defined endocrine function of pancreatic islet cell tumours. Thirty pancreatic islet cell tumours were histologically classified and analysed for their possible peptide hormone content using the immunohistoperoxidase method. Seven tumours contained insulin, six tumours contained gastrin and eight tumours contained glucagon. One tumour contained all three hormones. In the insulin and gastrin-containing tumours, the cells were usually arranged in solid nests of cells, with tubular and acinar formations in about half the cases. In the glucagon-containing tumours the cells were mainly arranged in anastomosing ribbons consisting of one of two layers of small cells. Most of the hormone-containing tumours were argyrophilic using Grimelius' silver reaction. All but one of the glucagon-containing tumours were incidental findings at autopsy. About half of the other tumours had metastasized. It is concluded that a relation exists between the histological pattern of growth and immunohistochemically defined endocrine function of pancreatic islet cell tumours.


ELISA: enzyme-linked immunosorbent assay. Similar in design to radioimmunoassay, comparable in sensitivity and specificity but easier, safer, and less expensive, this new diagnostic technique uses enzyme-labeled rather than isotope-labeled reagents. The end point is a color change that can be assessed by colorimetry or with the naked eye. Various techniques of ELISA are described, along with examples of current and potential clinical applications.


Ultrastructural and enzyme histochemical study of ovarian hilar cells in women and their relationships with sympathetic nerves. The ultrastructure of normal ovarian hilar cells, both during the reproductive era and after the menopause, shows evidence of steroid hormone synthesis. In this respect these cells are very similar to Leydig cells in that they contain mitochondria with a dense matrix, a highly developed smooth endoplasmic reticulum, Reinke crystals, and microcystalline inclusions. The latter are much more numerous than in the normal testis. Their enzymatic activities are quite similar to those of Leydig cells. Ovarian hilar cells seem to originate from progressive metamorphosis of fibroblastic cells under the induction of sympathetic nervous structures. Their relations with hilar nerves are of three types: simple direct membrane contact without a Schwann cell sheath, intimate intracytoplasmic relationships, and specialized contacts, which are comparable to a synapse.


Genetic studies on the Gc subtypes.

Genetic studies on the Gc subtypes. Gc subtypes were determined by immunofixation isoelectric focusing. In a family study involving 93 families with a total of 176 children, a three-allele model with six genotypes was confirmed. The distribution of Gc subtypes was studied in three populations from Europe and in a sample of Druzes from Northern Israel. Three new variant Gc types were observed.


Localization of a gene for human alpha-galactosidase B (= n-acetyl-alpha-d-galactosaminidase) on chromosome 22. The localization of the structural gene for human alpha-galactosidase B (= N-acetyl-alpha-galactosaminidase) was investigated by means of man-Chinese hamster and man-mouse somatic cell hybrids. The hybrid clones were analyzed for chromosomes and for a large number of known enzyme markers. The lysates of the hybrid cells were treated with Sepharose-coupled antihuman alpha-galactosidase B and the activity of the adsorbed enzyme was measured on the Sepharose beads as N-acetyl-alpha-galactosaminidase. The results show that the structural gene for human alpha-galactosidase B is situated on chromosome 22, and that there is no structural relationship between human alpha-galactosidase A and human alpha-galactosidase B.


Histological types of nasopharyngeal carcinoma in an intermediate risk area. Between April and December 1974, 485 cases of NPC were seen at the Salah Azaïz Institute in Tunis. A histological study was carried out according to a classification that comprises four types of tumour:well-differentiated squamous-cell carcinoma, poorly-differentiated squamous-cell carcinoma, 'nasopharyngeal' type carcinoma and an anaplastic type. Some correlation between these histological types and clinical, epidemiological, virological and prognostic features was found.


Analytical aspects of symptoms of nasopharyngeal malignancies. The various symptoms of 766 patients with nasopharyngeal malignancies (641 carcinomas and 125 malignant lymphomas, confirmed histologically) were analysed statistically from the viewpoint of early diagnosis. These can be divided into aural, nasal, pharyngeal, ophthalmic, cervical lymph node and cranial nerve symptoms. The frequencies of these symptoms were compared in patients with tumours of different histopathological classifications: the nasopharyngeal malignancies were divided into carcinoma and malignant lymphoma, and the carcinomas were subclassified according to their degree of differentiation. On the whole, lymphoma patients more often had nasal and pharyngeal symptoms, and carcinoma patients ophthalmic and cranial nerve symptoms. It is considered that this difference is due to the different ways in which the two kinds of tumour develop. The frequencies of the symptoms naturally increased with the clinical course of the disease; the frequencies of the symptom both as an initial sign and as observed during the clinical course of the disease were examined. Nasopharyngeal malignancies are not indicated by localized symptoms but become evident when adjoining organs, such as the ear or nose, give some sign of abnormality. In not a few cases, a neck swelling is the initial sign; and in some patients, cranial nerve involvement is the first symptom. Since a patient may not understand the significance of his symptom and may consult a general surgeon, physician, ophthalmologist and/or paediatrician, these specialists should be alerted to the recognition of this disease.


Descriptive and analytical epidemiology of nasopharyngeal cancer. Information concerning the descriptive and analytical epidemiology of NPC that has been reported mainly since the first international symposium on the subject in Singapore in 1964 are reviewed. NPC is rare in most countries in the world, with an age-adjusted incidence rate of less than 1 per 100,000, and the incidence rate is twice as high in males as in females. Chinese of southern origin have a uniquely high risk, the incidence rates per 100,000 being 10--20 in males and 5--10 in females. The greater the admixture of southern Chinese blood in a given ethnic group, the more likely it is that the NPC incidence rate in that group will be raised. The incidence in both sexes begins to rise after the ages of 20--24 and reaches a plateau at between 45 and 54. When the logarithm of mortality and morbidity is plotted against the logarithm of the age, the power of the age that provides the best fit to a straight line on a log-log graph is approximately two to four. These figures are lower than for other cancers. Seroepidemiological case-control studies indicate that both different birthplace and abnormal response to EBV antigen significantly enhance the risk for NPC; when these two factors are combined, the relative risk appears to rise further. The effect of other environmental chemicals, such as from cigarette smoking, shown to be significant in several retrospective studies, could explain in part epidemiological phenomena such as sex difference in incidence. The definitive reason for the uniquely high risk in southern Chinese should be further investigated by taking into account the interactions of host factors (birthplace, HLA, etc.) and environmental factors (EBV, chemical carcinogens including nitrosamines, excessive intake of salted fish, nutritional deficiencies, etc.).


Histopathological types of nasopharyngeal carcinoma in a low-risk area: Japan. NPC in Japan was studied histopathologically by examining 816 NPCs from among 3 338 biopsies from patients with tumours of the nasopharynx and other parts of the upper respiratory system. In addition, a comparative study on NPC among Taiwanese and an immunoserological study were carried out. When comparing histological types of malignant tumours of the upper respiratory tract, poorly-differentiated squamous-cell carcinoma predominated only in those of the nasopharynx. Malignant nasopharyngeal tumours in Japanese patients were characterized by two histological features: predominance of squamous-cell carcinoma, especially of the poorly-differentiated type, and a relatively high frequenty of malignant lymphoma. An analysis of 731 cases of NPC showed that a vast majority (86.7%) were poorly-differentiated and a minority (13.3%) well-differentiated squamous-cell carcinomas. The former included 45.8% spindle-polygonal-cell carcinomas, 26.6% transitional-cell carcinomas ana 14.3% lymphoepitheliomas. Although the transitional-cell carcinomas and lymphoepitheliomas showed a peculiar morphology, it was confirmed that they are of a squamous nature. A comparative study of the histology of NPCs in a high-risk area, Taiwan, and in a low-risk area, Japan, revealed considerable differences between the two groups. Well-differentiated carcinomas were infrequent in both groups but were more frequent in Japanese than in Taiwanese, while the frequency of poorly-differentiated carcinomas, especially transitional-cell carcinomas and lymphoepitheliomas, was much higher among Taiwanese. A seroepidemiological study on the relation of anti-VCA antibody titres to histological type of tumour in 84 Japanese NPC patients revealed that the rate of positivity and the geometric mean of the titres were considerably higher in patients with lymphoepitheliomas. Althougropathological study along this line would appear to be important, since the results obtained in Japanese NPC cases may suggest that EBV genomes in NPC cells vary with the grade of differentiation of NPC.


Histological typing of nasopharyngeal carcinoma. There is little agreement about correlations between histological type and the epidemiological and biological characteristics of NPC. This is largely due to variations in terminology and diagnostic criteria. The use of the terminology and definitions proposed by WHO would facilitate and improve international comparisons.


Morphological transformation of nasopharyngeal epithelial cells in vitro by Epstein-Barr virus from B95-8 cells. Tissue fragments of fresh biopsy specimens from the non-neoplastic NP mucosa of 20 subjects, from the tumours of 10 NPC patients, from the mucosa of freshly removed tonsils from nine subjects and from the primary lesions of seven patients with malignancies of the upper respiratory or alimentary tract other than NPC were infected with EBV derived from B95-8 cells. A significantly higher frequency of growth stimulation and a greater mean growth ratio between infected and uninfected fragments from the same source were observed in the non-neoplastic NP mucosa specimens than in the others. In addition, the growth characteristics and the morphology of the cells in the infected non-neoplastic NP mucosal explants resembled those of transformed cells; but whether they possess malignant potential is being investigated.


Epstein-Barr virus-epithelial cell interaction and its implication in the etiology of nasopharyngeal carcinoma. The etiological role of EBV in NPC is still a matter for debate. A major question is how the viral DNA becomes associated with the carcinoma cell, since only B lymphocytes are at present known to have receptors to EBV. The following hypotheses are proposed: (1) The epithelial cells of the nasopharynx have EBV receptors in vivo; transformation of the epithelial cell thus results from a direct interaction between EBV and this cell type. The epithelial cells of the nasopharynx are not permissive for EBV infection. In this case: (2) Malignant or premalignant changes in the epithelial cells are required for EBV infection to take place. Thus, EBV may act either as a passive passenger or as an active promoter in NPC development. Or, (3) infection of the epithelial cells results from a specific interaction (involving either transfection or hybrid formation) between an EBV-infected B lymphocyte and an epithelial cell within the nasopharynx. Here again, the virus may either be passive or act as an oncogenic factor. Recent data are presented both for and against these hypotheses.


Early and late components of Epstein-Barr virus-associated membrane antigen in superinfected Daudi cells and their reactivity with sera from nasopharyngeal carcinoma patients. Investigations were carried out on newly synthesized MA, VCA and EA in Daudi cells superinfected with the P3HR-1 strain of EBV and treated with trypsin to remove previously adsorbed MA-positive material from the cell surface. Synthesis of MA, VCA and EA was completely blocked by puromycin. A marked reduction in the frequency of MA-positive cells was observed in the infected cell cultures in the presence of either Ara-C or PA, but a fraction of the MA-positive cells was insensitive to the inhibitors. Differential absorption of an EBV antibody-positive human serum with Ara-C-treated or -untreated infected cells revealed two antigenically different components of MA: early (Ara-C-insensitive) and late (Ara-C-sensitive) MA. Three of five sera from patients with NPC, but none of five sera from normal adults, showed an apparent 'prozone' phenomenon in their reactivity against late but not early MA.


Heterogeneity of Epstein-Barr virus derived from P3HR-1 cells. Infection of cells of the EBV-free human B-lymphoma lines BJAB and Ramos resulted in conversion of these cells to EBV-genome carriers expressing EBNA. EBV isolates from P3HR-1 cells induced a heterogeneous EBNA pattern: both a faintly granular pattern and brilliant EBNA-expression were observed. The two types of EBNA-expressing cells could be separated upon cloning. Brilliantly EBNA-expressing cells always segregated varying percentages of EBNA-negative cells. An EBNA-negative subclone derived from these cells was devoid of detectable EBV DNA. Nucleic acid hybridization experiments failed to reveal a correlation between the intensity of EBNA expression and the number of EBV genome equivalents per cell. EBV genome-containing cells had an average of 14-fold more cells showing EA synthesis after superinfection by P3HR-1 virus, when compared with EBNA-negative cells infected under identical conditions. Studies on the kinetics of EA induction in EBNA-positive and EBNA-negative cells indicate that complementation is required for the induction of EA after superinfection.


Expression of latent Epstein-Barr virus genomes in human epithelial/Burkitt's lymphoblastoid hybrid cells. Expression of latent Epstein-Barr virus genomes in somatic-cell hybrids of Burkitt's lymphoblastoid cells has been studied. Treatment of the hybrid cells, D98/Raji and D98/HR-1, with IUDR induced the formation of EA and VCA and replication of virus DNA, whereas the same treatment of Raji cells induced only the formation of EA. The patterns of transcription of virus genomes in these three cell lines were, however, very similar: 25% without treatment with IUDR, 30% immediately after the treatment and 50% (entire genome transcription) three days after being transferred to fresh medium. The amount of virus RNA in the cells, calculated from DNA-RNA hybridization kinetics, was proportional to the number of virus genomes per cell, suggesting that every copy of virus DNA in these cells is actively transcribed.


Interaction between Epstein-Barr virus and type-C virus in human cells. The interaction between EBV and type-C viruses was studied in our FVNC experimental system, in which EBV and type-C viral genomes are contained in each cell. The data indicate that the human lymphoid FVNC cells are sensitive to both EBV and type-C virus exposure, showing high frequencies of induction of both repressed viral genomes. The two different viral genomes may be associated with different chromosomes in individual cells.