bluuebunny/crossref_metadata_2025 huggingface dataset:
Behaviour and Personality in Childhood as Predictors of Adult Psychiatric Disorder
Authors: Rodgers Bryan
Published: December 2006

Abstract Associations between childhood behaviour and personality and adult affective disorder were investigated in a 36‐year follow‐up of a national birth cohort. A number of early characteristics were significantly related to adult outcome including enuresis, nail‐biting, speech problems, truancy and composite indices of behaviour and personality. Continuity was not explained by factors acting independently on child and adult measures. Prediction of adult disorder, although better for women, was modest in both sexes and sensitivity and specificity would not justify widespread intervention. However, childhood measures should prove valuable in investigating chains of influence on adult disorder, occurring throughout individuals′ life histories.
Premature Termination from Treatment among Children Referred for Antisocial Behavior
Authors: Kazdin Alan E.
Published: December 2006

Abstract The present study examined differences between children and families who complete treatment versus those who terminated prematurely. Children (N=81, ages 7–13 years) referred to outpatient treatment for severe antisocial behavior and their families participated. It was predicted that families who terminate treatment prematurely would show greater dysfunction in four domains: child severity and breadth of antisocial behavior, maternal stress, maternal psychopathology, and socioeconomic disadvantage. The results indicated that among cases who terminate treatment prematurely children evinced more severe conduct disorder symptoms and more delinquent behaviors; mothers reported greater stress from their relations with the child, their own role functioning, and life events; and families were at greater socioeconomic disadvantage than those who remained in treatment. The implications of the present findings for the design and implementation of treatment of antisocial children and their families are discussed.
Sex Differences in the Hyperkinetic Syndrome of Childhood
Authors: James A. , Taylor E.
Published: December 2006

Abstract Among a clinic sample of 6525 subjects, 61 males and 18 females with an ICD‐9 diagnosis of the hyperkinetic syndrome of childhood were identified. Hyperactive girls had a lower IQ and significantly higher rates of language disorders and neurological disorders, suggesting a possible neurological basis for hyperactivity in females. In contrast, there was a population of male hyperactives with less evidence of brain dysfunction and a normal IQ, evidence compatible with the model of greater male constitutional variability. There was little evidence for the polygenetic multiple threshold model of sex inheritance.
Confirmatory Factor Models of Attention Deficit and Conduct Disorder
Authors: Fergusson D. M. , Horwood L. J. , Lloyd M.
Published: December 2006

Abstract The paper presents four alternative confirmatory factor models to represent the structure of measures of attention deficit and conduct disorder obtained from multiple sources. These models range in complexity from a simple one‐factor model with no method effects to a two‐factor model with method effects. These models were fitted to data gathered on maternal, teacher and self‐report of attention deficit and conduct disorder for a sample of New Zealand children studied at ages 9 and 10 years. The analysis strongly suggests that the best representation of the data was a two‐factor model in which there were distinct factors of attention deficit and conduct disorder with these factors being highly correlated (r= 0.87 – 0.88). It is suggested that the most suitable clinical nomenclature may be to describe conduct disorder and attention deficit generically as externalizing disorders, subscripting this classification with clauses which describe the relative contributions of conduct disorder and attention deficit. The implications of this finding for the measurement, classification and explanation of conduct disorder and attention deficit disorder are discussed.
Prediction of Cognitive Competence in Kenyan Children from Toddler Nutrition, Family Characteristics and Abilities
Authors: Sigman Marian , McDonald Mary Alice , Neumann Charlotte , Bwibo Nimrod
Published: December 2006

Abstract This study explored the extent to which cognitive competence in 5‐yr old Kenyan children was associated with earlier nutritional factors, family conditions and toddler characteristics. Food intake during the 18th–30th mths and physical stature at 30 mths were associated with cognitive skills at 5 yrs. Measures of family background, abilities of the child as a toddler and current schooling were also associated with cognitive abilities at 5 yrs. These variables influenced development independently, so that later cognitive competence was best predicted by a combination of earlier nutritional, family and toddler characteristics.
Patterns of Confiding Relationships among Adolescent Girls
Authors: Monck Elizabeth
Published: December 2006

Abstract In a community population of girls aged between 15 and 20 years, a sample of 142 girls provided information on their confiding relationships. A clear preference emerged for using other girls and women as problem solvers and intimate confidants. Mothers were the most usual first‐named problem solver, but intimate confiding was affected by the quality of the mother‐daughter relationship. Confiding in fathers was rare. From ages 15 to 18 girlfriends were the most commonly cited intimate confidant, with mothers and sisters in second place. At age 19 boyfriends were the most frequent intimate and instrumental confidants.
Revision, Replication and Neglect—Research on Maladjustment in Chronic Illness
Authors: Pless I. Barry , Nolan Terry
Published: December 2006

Abstract Children with chronic physical disorders have twice the risk of psychosocial maladjustment compared with healthy children. This “second handicap” poses a significant mental health problem. This review examines factors related to the child, family, and clinical condition that affect the risk of maladjustment, as well as die manner in which this knowledge has influenced intervention strategies. Much of the research reviewed represents replication of what is already known and important areas of enquiry have been neglected. Investigators are urged to work towards the further identification of high risk characteristics and to apply these to the development and evaluation of new preventive and therapeutic approaches for these children and their families.
Pervasive and Situational Hyperactivity—Confounding Effect of Informant: A Research Note
Authors: Costello Elizabeth J. , Loeber Rolf , Stouthamer‐Loeber Magda
Published: December 2006

Abstract Several studies of children with problems of hyperactivity, impulsivity, and inattention (HIA) have suggested that when such behaviour occurs in more than one setting, associated conduct problems, emotional symptoms, and functional impairment are more serious than when HIA problems are seen in one situation only. Analyses of parent and teacher reports on a community sample of 480 children aged 7–11 are presented to show that in some cases this conclusion may have resulted from a confound between informant and information. When children with situational HIA were divided into ‘home situational’ and ‘school situational’ subgroups, their scores on other measures of psychopathology and impairment varied, depending on whether the informant was the parent or the teacher. When the source of information was independent of parents'or teachers'judgments, no differences were found between situationally and pervasively HIA children. Implications for future studies of situational and prevasive HIA are discussed.
A Divided Attention Analysis of the Effects of Methylphenidate on the Arithmetic Performance of Children with Attention‐Deficit Hyperactivity Disorder
Authors: Carlson Caryn L. , Pelham William E. , Swanson James M. , Wagner Jana L.
Published: December 2006

Abstract Thirteen boys with Attention‐Deficit Hyperactivity Disorder (ADHD) completed 80 arithmetic problems presented on a computer screen by typing a two digit answer. On half the trials, a foot press was required to terminate a computer‐generated tone presented 2 seconds before, 1 second before, 1 second after, and 2 seconds after arithmetic problem presentation. Compared to placebo, methylphenidate resulted in significantly faster reaction times (RTs) to tone probes and faster answers to arithmetic problems when the two tasks did not overlap in time, but not when simultaneous processing was required when the probe was presented 2 seconds after arithmetic problems. When dual processing taxed cognitive capacity, methylphenidate still improved accuracy on the primary arithmetic task relative to placebo, but at the expense of speed of performance on the secondary RT task. When ADHD children fail to allocate available resources to a primary cognitive task, treatment with methylphenidate may result in reallocation of existing cognitive capacity from a secondary task to the primary task.
Conditional Probabilities of Child Interview Symptoms in the Diagnosis of Attention Deficit Disorder
Authors: Landau Steven , Milich Richard , Widiger Thomas A.
Published: December 2006

Abstract Based upon the standardized interviews of 76 clinic‐referred boys, children's reports of behaviors suggestive of attention deficit disorder (ADD) were examined to determine which symptoms were most efficient predictors of an ADD diagnosis. Unlike previous research that has focused exclusively upon the use of sensitivity and specificity rates, this investigation also employed the conditional probability rates of positive and negative predictive power to establish the diagnostic utility of symptoms. As such, this study attempted to establish the diagnostic efficiency of some of the child‐reported symptoms and describes a new method to examine any criteria set that is to be used for classification purposes. Results indicated that the optimal child‐reported predictors of an ADD diagnosis were not those symptoms typically considered hallmark indicators of the disorder. In addition, no symptom was found to be an efficient exclusion criterion for diagnosis. These findings are discussed in terms of the role of the child as informant for the diagnosis of children's behavior disorders and the need for multisource assessment.
Sociometric Status: Its Stability and Validity Among Neglected, Rejected and Popular Children
Authors: Ollendick Thomas H. , Greene Ross W. , Francis Greta , Baum Cynthia G.
Published: December 2006

Abstract Although important distinctions among sociometrically rejected, neglected, and popular children have been reported in the literature, concerns have been raised about use of negative peer nominations in identifying these children. A revised procedure developed by Asher and Dodge [Developmental Psychology, 22, 444–449 (1986)] eliminates the need to obtain negative peer nominations. In the present study, the construct validity of this revised procedure was explored and its long‐term stability examined over 6, 12 and 18 months. Our findings establish significant differences on several indices among rejected, neglected and popular children. However, the differences between rejected and popular children were more robust than those between neglected and popular children, who failed to differ from one another on most of the measures. Moreover, fairly good long‐term stability was found for popular and rejected status, whereas the long‐term stability for neglected status was quite poor. These findings were addressed in the context of similar research employing negative nomination methods. Implications for the identification of at‐risk children were also discussed.
The Emanuel Miller Memorial Lecture 1990 Cooperative Learning in Classrooms: Processes and Outcomes
Authors: Bennett Neville
Published: December 2006

This article focuses on the description and analysis of our research on cooperative grouping over the last 8 years. This research effort has moved through three interconnected phases–from description of classroom practice, to experimentation, to implementation.

Descriptions of typical classroom practice have established the paucity of cooperation. Groups tend to be no more than collections of children sitting together but engaged on individual work. In such groups the level of cooperation, frequency of explanations and knowledge exchange is low.

Thus, in order to gain an understanding of the nature and process of cooperation in groups on normal curriculum tasks required the setting up of within‐classroom experiments. These revealed, among others, that group composition is important to learning outcomes, and that pupil involvement substantially improves in cooperative group endeavours.

Missing, however, were data on the successful implementation of cooperative groups. Yet successful implementation has great contemporary relevance because of the demand for assessed skills in collaboration in the national curriculum. Our current work therefore addresses the impact of changing grouping practices on group processes, classroom management, the teacher's role and children's learning.

Preliminary findings from this study are presented together with a wider analysis of the state of the research field and possible ways forward.
Social‐Emotional Predictors of Preschoolers' Responses to Adult Negative Emotion
Authors: Denham Susanne A. , Couchoud Elizabeth A.
Published: December 2006

The study examined predictors of children's prosocial responses to adult negative emotions. An adult displayed anger, sadness and pain during play sessions with 39 preschoolers (mean age = 43 months). Older children responded more prosocially to all three emotions, whereas children with greater emotion knowledge responded more prosocially to the adult's sadness. Children who behaved prosocially in response to peers' negative emotions also were prosocial after the adult's negative emotions, even with effects of age and emotion knowledge held constant. Assertive children responded more prosocially to the adult's anger, even with effects of other variables held constant. Both theoretical and practical implications are discussed.
Child and Parent Perceptions of the Upsettingness of Major Life Events
Authors: Rende Richard D. , Plomin Robert
Published: December 2006

An adaptation of the Coddington Social Readjustment Rating Scale for use with first‐grade children was administered to 164 first‐graders and their parents. Parents indicated whether each event occurred and both parents and their children rated the upsettingness to the child. Parent ratings of stress are significantly higher than child ratings for specific events and a composite stress measure. Parent and child composite scores correlated 0.21 when the number of events was controlled. Implications for research on life events and childhood stress are discussed.
The Development of Psychological Well‐Being in Late Adolescence
Authors: Cairns Ed , McWhirter Liz , Barry Robert , Duffy Ursulla
Published: December 2006

Studies following adolescents from school to work indicate a sharp decrease in psychological symptoms over the 16–17‐year period compared to a more gentle decrease subsequently. This could be a genuine developmental phenomenon, related to school leaving, or because anxiety levels are higher at age 16 years due to approaching examinations. The present study examined these hypotheses. GHQ scores for those at school were related to examination candidacy. Eighteen months later such differences had disappeared among those young people now in full‐time employment. Similarly, a group who remained in full‐time education also showed a significant decline in GHQ scores.
Chromosomes in Anorexia Nervosa. A Study of 47 Cases Including a Population‐Based Group: A Research Note
Authors: Råstam Maria , Gillberg Christopher , Wahlström† Jan
Published: December 2006

Forty‐seven cases with anorexia nervosa (including a total population group) and 47 sex‐, age‐, and school‐matched comparison cases were subjected to chromosome analyses in a blind fashion. No major abnormalities were found in any of the cases. Sex chromatin was analysed in buccal smears from the girls. No differences between the anorexia nervosa and the comparison cases were found. It seems that chromosomal/sex chromatin analyses in anorexia nervosa are not warranted.
Seasonal changes in the pigments, carbohydrates and growth of red spruce as affected by ozone
Authors: ALSCHER R. G. , AMUNDSON R. G. , CUMM1NG J. R. , FELLOWS S. , FINCHER J. , RUBIN G. , VAN LEUKEN P. , WEINSTEIN L. H.
Published: December 2006

Two‐year‐old red spruce seedlings were exposed to various levels ot ozone, from 0.4 to 3 times ambient levels, in open‐top chambers in Ithaca, NY, USA. Exposures, which varied with changes in day length, commenced on May 30, 1987 and continued until December 14, 1987. Seedling biomass, carbohydrate contents, pigment contents, and rate of electron transport were assessed twice monthly during the fumigation period. Orthogonal quadratic or cubic polynomials were used to model the response through time each variable measured. A one‐way analysis of variance model was fitted to every regression coefficient in each polynomial model to test for ozone effects on seasonal physiological patterns. Ozone did not influence growth, foliar pigment content, foliar starch content, root carbohydrate content, or rate of electron transport. The seasonal change of needle raffinose content differed between exposed to low (0.4 ×, 1×) and high (2×, 3×) ozone levels. There was also a trend towards reduced total soluble sugar content foliage during late autumn in higher ozone treatments.
ONTOGENETIC DEVELOPMENT OF ADENYL CYCLASE AND PHOSPHODIESTERASE IN RAT BRAIN
Authors: Weiss B.
Published: December 2006

Abstract— The activities of adenyl cyclase and phosphodiesterase were determined in homogenates of cerebrum, cerebellum and brain stem of rats of 1 day to 9 weeks of postnatal age. The activity of cerebral and brain stem adenyl cyclase measured either in the absence or presence of sodium fluoride increased rapidly for 2 weeks, reached at 20 days a maximum about three times (brain stem) or six times (cerebrum) that seen on day 1 and then declined slightly during the next several weeks. In contrast, activity of cerebrellar adenyl cyclase increased more slowly and reached a maximum at about 32 days. Activity of phosphodiesterase in cerebrum and brain stem increased several‐fold during brain maturation; however, enzymic activity in the cerebellum decreased during the entire 9 week period.

In the pineal gland, adenyl cyclase activity measured in the absence of norepinephrine or sodium fluoride did not change significantly with age. However, enzymic activity measured in the presence of these agents increased with the age of the rat. Bilateral removal of the superior cervical ganglia at 1 day of age is known to arrest the sympathetic innervation of the pineal gland but did not prevent the development of this adenyl cyclase system activated by catecholamines or fluoride.
REGIONAL DISTRIBUTION OF AMINO ACIDS IN HUMAN BRAIN OBTAINED AT AUTOPSY
Authors: Perry T. L. , Berry K. , Hansen S. , Diamond S. , Mok C.
Published: December 2006

Abstract— Contents (μmol/g wet wt.) of 35 free amino acids and related compounds were measured in 12 different regions of each of five human brains. Specimens were obtained at autopsy from patients who died suddenly without previous brain disease. These data may serve for later comparison with contents of amino compounds in similar regions of the brains of patients dying with various neurological or psychiatric disorders.

There were marked and consistent differences in the regional distribution of the following eight compounds: γ‐aminobutyric acid, homocarnosine, glutamic acid, aspartic acid, taurine, cystathionine, glycerophosphoethanolamine, and phosphoethanolamine. These differences suggest that some of these compounds may have special physiological roles, including the possible mediation of synaptic transmission.

Human brain contains two previously unreported compounds, the mixed disulphide of cysteine and glutathione and α‐(γ‐aminobutyryl)‐lysine. The latter dipeptide occurs in much higher concentrations in human brain than in the brains of lower mammals.
SOME PROPERTIES OF SOLUBLE AND SOLUBILIZED PARTICLE‐BOUND HEXOKINASE1
Authors: Bigl V. , Muller L. , Biesold D.
Published: December 2006

Abstract— Particle‐bound hexokinase of rat brain homogenates was solubilized by successive treatment with 0‐9 M‐NaCl or 003 M‐ATP (pH 8.0) and 0‐5% (w/v) Triton X‐100. This solubilized hexokinase and the soluble hexokinase present in cytoplasm of rat brain homogenates were chromatographed on DEAE‐cellulose and some kinetic properties of the isolated hexokinase peaks were studied. The chromatographic separation was greatly influenced by the EDTA‐concentration of the buffer used. No significant differences were observed in the chromatographic pattern and in the apparent Km‐values for ATP and glucose and the apparent Kt for glucose‐6‐phosphate (versus ATP) between the soluble and particulate hexokinase solubilized by different reagents. On agarose‐electrophoresis the solubilized particulate enzyme migrates as one single band, the soluble hexokinase separates into one major and two minor bands.
PROTEIN METABOLISM AND AMINO ACID ACCUMULATION IN THE RAT SUBMAXILLARY GLAND DURING REDUCED SYMPATHETIC ACTIVITY
Authors: Kidman A. D. , Weiss B. , Costa E.
Published: December 2006

Abstract— Unilateral sympathetic decentralization of the superior cervical ganglion of rats was performed 3 days prior to the experiments. A two‐compartment kinetic model was proposed to describe the effect of decentralization on (1) the uptake of a nonphysiological amino acid from plasma to the submaxillary gland and (2) the incorporation of a physiological amino acid from precursor pool into protein. The calculations based on the model showed that the fractional rate constant for efflux of the nonphysiological amino acid, α‐[3‐14C] aminoisobutyric acid, was greater in the decentralized than in the normal gland. However, efflux rate was equal in the two glands because the extrapolated zero time value of the initial concentration was greater in the normal gland.

The labelled physiological amino acid, [14C]leucine, was used in initial experiments to assess turnover rate of the gland proteins but it was rapidly metabolized to many other radioactive compounds. Therefore, arginine[14C]guanido was employed‐arginine being the only labelled amino acid found after injection. Since the steady state content of submaxillary gland proteins was not changed but the fractional rate constant of conversion of free arginine into protein (kp) was greater in the decentralized gland (kp= 0‐40 h_l) than in the normal (kp= 0‐27 h−1), we can conclude that decentralization increases protein turnover rate; thus, assuming that arginine[14C]guanido is homogeneously distributed in the tissue pools of free arginine, the rate of protein turnover is greater in the sympathetically decentralized gland than in the normal.
FAST AXOPLASMIC TRANSPORT IN MAMMALIAN NERVE IN VITRO AFTER BLOCK OF GLYCOLYSIS WITH IODOACETIC ACID
Authors: Ochs S. , Smith Carolyn B.
Published: December 2006

Abstract— Fast axoplasmic transport of components incorporating L‐[3H]leucine in cat sciatic nerve occurred in vitro at a rate of 407 ± 21 (S.D.) mm/day. Although fast transport had earlier been shown to be blocked within 10 to 15 min by asphyxiation with nitrogen or by agents such as NaCN or dinitrophenol that interfere with oxidative phosphorylation, interruption of glycolysis by application of iodoacetate resulted in a gradually diminishing transport with a complete block in about 2 h. This block characteristically showed a sloping front instead of the usual crest of activity found in the nerve after the 3 h period usually allowed for in vitro downflow. The declining slope of radioactivity in the nerve seen after exposure to iodoacetate was not the result of a delayed entry of iodoacetate into the nerve fibres. We consider it to be the consequence of a limited and diminishing supply of endogenous metabolites entering the tricarboxylic acid cycle below the site of glycolytic block by iodoacetate. When either pyruvate or L‐lactate was supplied to the iodoacetate‐blocked nerve, recovery of the normal pattern and distance of flow was effected. Pyruvate partially reversed the iodoacetate block at concentrations as low as 2 mM, with almost complete recovery at approximately 25 mM. A concentration of L‐lactate approx. 20 times that of pyruvate was required for a comparable degree of reversal of iodoacetate block.
FRACTIONATION OF GOLDFISH BRAIN AMINOACYL‐TRANSFER RNA AT THE MICROGRAM LEVEL 1
Authors: Kaplan B. B. , León V. De , Sirlin J. L.
Published: December 2006

Abstract— The methylated albumin‐kieselguhr column first employed by SUEOKA and YAMANE (1962) to fractionate tRNA was modified and scaled down by a factor of 100 to permit the separation of 1 y% of goldfish brain tRNA. Double labelling, co‐chromatography of single aminoacylated tRNA species demonstrated that the column can characterize isoaccepting tRNAs without serious loss of resolution. The procedure is simple and reproducible and can be useful for the rapid scanning of tRNAs from limited amounts of biological material. Further scaling down of the procedure appears to be feasible.
LIPID PEROXIDE FORMATION IN RAT BRAIN
Authors: Bishayee Subal , Balasubramanian A. S.
Published: December 2006

Abstract— Lipid peroxide formation as measured by the thiobarbituric acid reaction was demonstrated in subcellular fractions of rat brain. The ascorbic acid induced nonenzymic lipid peroxidation was distributed in all the subcellular fractions with a maximum in microsomes. The NADPH dependent enzymic lipid peroxidation occurred mainly in microsomes and to a smaller extent in synaptosomes; NADH could replace NADPH for the enzymic lipid peroxidation under the assay conditions employed. Fe2+ but not Fe3+ stimulated the NADPH or NADH dependent lipid peroxide formation. The optimum conditions with respect to pH, ascorbic acid or NADPH concentration, time of incubation and protein concentration were studied. Heating the microsomes at 100oCdid not influence the ascorbate‐induced lipid peroxidation but completely abolished the NADPH linked peroxidation. Several heavy metal ions, surface active agents and EDTA were inhibitory to lipid peroxidation. The effect of thiol agents indicated that ‐SH groups were involved in the enzymic lipid peroxidation. Studies on subcellular fractions of developing rat brain showed an increasing trend in lipid peroxidation with the advancing age of the animal. No significant difference in lipid peroxidation was observed between brains from normal rats and those from rats affected by experimental allergic encephalomyelitis.
A PROCEDURE FOR THE MEASUREMENT OF HEMICHOLINIUM‐3 IN BRAIN TISSUE
Authors: Slater P. , Stonier P. D.
Published: December 2006

Abstract— The natural fluorescence of hemicholinium‐3 (HC‐3) was used to provide a method for determining its concentration in brain tissue following intraventricular administration of the compound to rats and rabbits. When hemicholinium‐3 was perfused through the cerebral ventricles of the rabbit, the highest concentration was found in the pons‐medulla oblongata. The effect of a number of compounds on the uptake of hemicholinium‐3 in the brain was studied in rats. Choline and tetramethylammonium significantly reduced the uptake of HC‐3 from the cerebral ventricles but tetraethylammonium, physostigmine and atropine had no effect. The results are discussed in relation to the known effects of hemicholinium‐3 in the central nervous system.
RAPID TRANSPORT OF FUCOSYL GLYCOPROTEINS TO NERVE ENDINGS IN MOUSE BRAIN
Authors: Zatz M. , Barondes S. H.
Published: December 2006

Abstract— Mice were injected intracerebrally with mixtures of [3H]fucose and [14C]gluco‐samine, and incorporation into macromolecules in various subcellular fractions of brain was studied at 1, 2, 3 and 4 h after administration of the precursors. There was a lag of several hours between the incorporation of [3H]fucose into the glycoproteins of the whole brain fractions and of that into the soluble and particulate glycoproteins of the nerve ending fractions. In contrast, no lag was observed between the incorporation of [14C]glucosamine into the macromolecules of the whole brain fractions and of that into the soluble macro‐molecules of the nerve ending fraction. We conclude that fucosyl glycoproteins of the nerve ending fraction were synthesized in the nerve cell bodies and transported to nerve endings by rapid axoplasmic transport, whereas a substantial proportion of the glucosamine in the soluble macromolecules of the nerve ending fraction was incorporated by the nerve endings themselves. In addition, our evidence indicates that cyclobeximide inhibited fucose incorporation into brain glycoproteins by inhibiting the synthesis of acceptor proteins rather than fucosyl transferase.
STUDIES ON S‐ADENOSYLHOMOCYSTEINE INHIBITION OF HISTAMINE TRANSMETHYLATION IN BRAIN
Authors: Baudry M. , Chast F. , Schwartz J.‐C.
Published: December 2006

Abstract— The mechanism of histamine methyltransferase (HMT) inhibition by S‐adenosylhomocysteine (SAH) has been investigated on a partially purified enzyme from guinea‐pig brain. The kinetic data indicated that this inhibition was competitive with respect to S‐adenosylmethionine (SAMe) and noncompetitive with respect to histamine. The Kt, values (about 5 ± 10−6 M in both cases) indicated that SAH had a higher affinity than SAHe or histamine for the enzyme.

In rats, after administration of a small dose of SAH, methylation of intracisternally injected [3H]histamine was not modified.

However, treatment with l‐DOPA or pyrogallol induced a decrease in [3H]histamine methylation, presumably due to a modification in the SAMe/SAH ratio in the brain. Hence, histamine methylation in brain could be regulated according to the value of this ratio and thus related to methylation of other biogenic amines.
THE ACTIVITIES OF BUTYRYLCHOLINESTERASE AND CARBONIC ANHYDRASE, THE RATE OF ANAEROBIC GLYCOLYSTS, AND THE QUESTION OF A CONSTANT DENSITY OF GLIAL CELLS IN CEREBRAL CORTICES OF VARIOUS MAMMALIAN SPECIES FROM MOUSE TO WHALE
Authors: Tower D. B. , Young O. M.
Published: December 2006

Abstract— The question of a constant density of glial cells in mammalian cerebral cortex regardless of species was examined by surveying the cortical activities of two enzymes primarily localized to dial cells. The cortical activity of butyrylcholinesterase (EC 3.1.1.8) was essentially constant at a rate of approx. 0.1 μmol of butyrylthiocholine hydrolysed min‐1 g‐1 over the range of species from rat (brain wt., 1.6 g) to fin whale and sperm whale (brain wt., 6800 and 7800 g, respectively). Over the same range the activity of cortical acetylcholinesterase, a neuronal enzyme, decreases by a factor of 7. Thus, butyrylcholinesterase ranged from < 2 per cent (in small rodent brains) to approximately 10 per cent (in whale brain) of the cortical acetylcholinesterase activity. The cortical activity of carbonic anhydrase (EC 4.2.1.1) was constant at a rate of 6.2 (± 0.25) μmol of CO2 evolved min‐1 g‐1 over the range of species from guinea‐pig (brain wt., 4.75 g) to fin whale (brain wt., 6800 g). These data obtained by assaying the dehydration reaction were confirmed by limited assays of the esterase activity of the enzyme (with p‐nitrophenylacetate as substrate) and agreed with limited, previously reported data for the hydration reaction. Thus, the circumstantial evidence strongly favoured a relative constancy of cortical glial cell density regardless of species.

The rates of anaerobic glycolysis in the cerebral cortex of various species were also investigated. For six species from mouse (brain wt., 0.4 g) to beef (brain wt., 380 g) cortical anaerobic glycolysis varied only slightly in the range of 50–62 μmol of CO2 evolved h‐1 g‐l, whereas cortical oxygen consumption for the same range of species decreased by a factor of 3. Previously frozen samples of beef cortex glycolysed at 35 per Cent of the rate of fresh (unfrozen) samples. Since identical rates were obtained for previously frozen samples of fin whale cerebral cortex, we concluded that the relative constancy of cortical anaerobic glycolysis could be extended to the range from mouse to whale and that this aspect of cortical metabolism is probably primarily glial in localization. Some implications of the latter conclusion for the proposed role of astrocytes as modulators of neuronal activity have been discussed.
THE EFFECTS OF UNDERNUTRITION ON THE PROTEINS OF OPTIC AND SCIATIC NERVES DURING DEVELOPMENT
Authors: Wood J. G.
Published: December 2006

Abstract— Polyacrylamide gel electrophoresis has been used to assess the appearance of some optic and sciatic nerve proteins in normal developing rats and in undernourished rats. Of the myelin proteins, the‘Wolfgram’proteolipid is already present about the time myelination begins. The basic myelin proteins appear later, first in sciatic and then in optic nerve. A non‐myelin basic protein, assumed to be a histone, is present at high levels in both nerves before myelination begins. There is no apparent effect of undernutrition on the appearance and amount of myelin proteins at 12, 16 and 22 days of age. The‘histone’protein is reduced in optic and sciatic nerves at times corresponding roughly to the transition periods from cellular proliferation to myelin formation. The possibilities are discussed that myelin basic proteins are synthesized as compact myelin formation occurs, and that there may be retarded cellular proliferation in nerves of undernourished rats.
ARYLSULPHATASE A (EC 3.1.6.1) ACTIVITY IN RAT CENTRAL NERVOUS SYSTEM DURING EXPERIMENTAL ALLERGIC ENCEPHALOMYELITIS
Authors: Maggio B. , Maccioni H. J. , Cumar F. A.
Published: December 2006

Abstract— The activity of arylsulphatase A (EC 3.1.6.1) was measured in several brain sub cellular fractions during experimental allergic encephalomyelitis in rats. In the acute stage there was a slight but significant increase in the brain homogenate in comparison to that from control animals. The alteration appeared to be localized in a subcellular fraction con stituted mainly by myelin fragments. The arylsulphatase A activity returned to the control level in the recovery stage.
ALTERATIONS IN CATION LEVELS AND NA‐K ATPase ACTIVITY IN RAT CEREBRAL CORTEX DURING THE DEVELOPMENT OF COBALT‐INDUCED EPILEPSY1,2
Authors: Hunt W. A. , Craig C. R.
Published: December 2006

Abstract— This study was carried out to ascertain what biochemical changes might be present in cobalt‐induced epilepsy in the rat. Sodium, potassium, calcium, magnesium, Na‐K ATPase activity, water content, protein content and the ability of the tissue to utilize oxygen were measured in (1) the area of the cerebral cortex in which the cobalt was implanted; (2) in an area adjacent to but not including the area of the lesion; and (3) in the homotopic area of the contralateral cerebral cortex. The greatest changes were observed in the area of the lesion itself, with marked increases in calcium, magnesium and sodium contents and decreases in potassium content, Na‐K ATPase activity, protein content and the ability of the tissue to utilize oxygen. The only significant findings in the area adjacent to the lesion and in the contralateral cortex were a modest elevation of sodium and a modest decrease in potassium at different time periods after implantation of the cobalt. We feel that the changes observed at the site of cobalt implantation may reflect tissue destruction which is unrelated to the epileptic process.
CHOLINE: SELECTIVE ACCUMULATION BY CENTRAL CHOLINERGIC NEURONS
Authors: Kuhar M. J. , Sethy V. H. , Roth R. H. , Aghajanian G. K.
Published: December 2006

Abstract— Most of the cholinergic input to the hippocampus was destroyed by placement of lesions in the medial septal area. In animals with such lesions we found that hippocampal ChAc activity was reduced by 85–90% and endogenous acetylcholine levels were reduced by more than 80 %. When hippocampal synaptosomes from animals with lesions were incubated with [3H]choline at concentrations of 7.5 nm, 1 μm and 10 μm there was approximately a 60 % reduction in the uptake of [3H]choline, suggesting that cholinergic nerve endings were mainly responsible for [3H]choline uptake. At 0.1 mm concentrations of [3H]choline, there was only a 25 % reduction of choline uptake, suggesting that at higher concentrations of choline there was more nonspecific uptake. The uptake of radiolabelled tryptophan, glutamate and GABA were only slightly or not at all affected by the lesions. There was a significant reduction of uptake of radiolabelled serotonin and norepinephrine, since known monoaminergic tracts were disrupted. Choline uptake was reduced only in brain regions in which cholinergic input was interrupted (i.e. the cerebral cortex and hippocampus) and remained unchanged in other regions (i.e. the cerebellum and striatum). The time course of the reduction in choline uptake was similar to that of the reductions in ChAc activity and endogenous ACh levels; there was no decrease at 1 day, a significant decrease at 2 days, and the maximal decrease at 4 days postlesion. There was a close correlation among choline uptake, ChAc activity and ACh levels in the four brain regions examined (i.e. the striatum, cerebral cortex, hippocampus and cerebellum). Our results suggest that when hippocampal synaptosomes (and perhaps synaptosomes from other brain areas as well) are incubated in the presence of choline, at concentrations of 10 μm m or lower, then cholinergic nerve endings are responsible for the bulk of the choline accumulated by the tissue.
INHIBITION OF ALANINE AND ASPARTATE AMINOTRANSFERASES BY α‐OXODERIVATIVES OF THE BRANCHED‐CHAIN AMINO ACIDS
Authors: Lysiak Wieslawa , Pienkowska‐Vogel Maria , Szutowicz A. , Angielski S.
Published: December 2006

Abstract—

L‐Alanine: α‐oxoglutarate aminotransferase was partly purified from rat brain and liver. The enzyme from the brain has about 10 times less activity than that from the liver.

Both enzymes have identical apparent Km values for L‐alanine, L‐glutamate, α‐oxoglutarate and pyruvate. Moreover they are competitively inhibited by L‐leucine. α‐oxoisocaproate and α‐oxotsovalerate. Obtained K, values are very similar and do not depend on the course of reaction.

α‐Oxoisocaproate inhibits the activity of crystalline L‐aspartate: α‐oxoglutarate aminotransferase; Kj is about 4–7 mM.

The pyridoxamine form of L‐alanine: α‐oxoglutarate aminotransferase seems to be more sensitive to the inhibitory effect of the compounds investigated.

The effect of branched‐chain amino acids and their α‐oxoanalogues on the metabolism of amino groups in maple syrup urine disease is discussed.
ANALYSIS OF PROTEINS UNDERGOING AXONAL TRANSPORT IN NIGRO‐STRIATAL NEURONS IN THE RAT
Authors: Singh V. K. , Fibiger H. C. , Mcgeer E. G. , McGeer P. L.
Published: December 2006

Abstract— An analysis of proteins undergoing axonal transport in nigro‐striatal neurons, after the stereotaxic injection of [3H]leucine into the substantia nigra of rat brain was performed. As early as 6 h after the injection [3H]proteins appeared in the caudate‐putamen. The maximum accumulation was at 5 days and there was still residual protein radioactivity present at 30 days. About 70 per cent of the total radioactive protein in the caudate‐putamen was solubilized by homogenization in 0–5%, (v/v) Triton X‐100 and remained in the supernatant on centrifuging for 1 h at 100,000 g. The supernatant fraction, when chroma‐tographed on a DEAE‐cellulose column, was resolved into four protein peaks (A, B. C and D) which were found to be labelled differently as a function of time after the injection of [3H]leucine. Peak A was substantially labelled in a first phase (6–24 h) and reached its maximum in a second phase (5 days). The proteins comprising this peak appeared to undergo both fast and slow axonal transport. Although some labelling in peak B was evident at 6 h, maximal activity did not occur until 5 days. No radioactivity could be detected in peaks C and D at 6 h. Maximal labelling of these two peaks also occurred at 5 days. These data suggest that the proteins of peaks B, C and D were transported primarily by slow axoplasmic flow. The radioactive protein peaks A and B from the second phase of the transport were excluded from a Sephadex G‐200 column, pointing to their high molecular weights (13,000–200,000). Peak B. which had the highest specific radioactivity (c.p.m./mg protein) at 5 days, contained a significant level of tyrosine hydroxylase, an important component of dopaminergic neurons.
CHARACTERIZATION OF WOLFGRAM PROTEOLIPID PROTEIN OF BOVINE WHITE MATTER and FRACTIONATION OF MOLECULAR WEIGHT HETEROGENEITY1
Authors: Wiggins R. C. , Joffe S. , Davidson D. , Valle U. Del
Published: December 2006

Abstract— Wolfgram proteolipid protein fraction (WPF) was prepared as the insoluble pellet resulting from the extraction of myelin three times with chloroform‐methanol (CM, 2:1, v/v). Amino acid composition analysis showed that the WPF described here is comparable to that described by Wolfgram (1966) and by Enget al. (1968). Disc gel electrophoresis in two different buffer systems revealed three major protein bands, W1, W2 and W3, having apparent mol. wt of 23,500, 54,000 and 62.000 daltons respectively. The 54,000–62,000 doublet is stable to performic acid oxidation and to reduction with β‐mercaptoethanol. Characterization of WPF by sedimentation velocity revealed two peaks having S20, w values of 1 96 and 0 84. In comparison, water soluble Folch‐Lees proteolipid apoprotein (APL) prepared in this laboratory (Hendricksonet al., 1972) differs from WPF in its amino acid composition and in its behavior on disc gels and in the ultracentrifuge. We employed preparative electrophoresis on polyacrylamide gels containing sodium dodecyl sulphate (SDS) in order to separate and purify heterogeneous components observed in WPF. We obtained a fraction containing essentially pure W1 protein and determined that it has a unique amino acid composition. Various fractions containing partly purified high molecular weight components were also recovered. Gel filtration chromatography on columns of Sephadex G‐200 was also successfully employed in this study of WPF.
CHANGES IN ADRENALS AND SYMPATHETIC NERVE TERMINALS FOLLOWING COLD EXPOSURE
Authors: West D. P. , Fillenz M.
Published: December 2006

Abstract— Rats kept at 3°C for 24 h show no significant change in the catecholamine content of the adrenals, although the protein content is raised. Whole heart ventricles show no change in noradrenaline content, but the vesicular pellet isolated from heart ventricles has a decreased noradrenaline concentration and DBH activity and an increased protein content.
SOLUTION PROPERTIES OF β NERVE GROWTH FACTOR PROTEIN AND SOME OF ITS DERIVATIVES
Authors: Pignatti P‐F. , Baker M. E. , Shooter E. M.
Published: December 2006

Abstract— The molecular weight of β nerve growth factor protein determined by sedimentation equilibrium in sodium acetate buffer, pH 40, and at protein concentrations around 0‐5 mg/ml agrees with the value obtained from the amino acid sequence and confirms the dimeric character of the protein under these conditions. At pH values of 5.0 or greater, β nerve growth factor protein shows either partial dissociation into monomers or aggregation to higher polymers or both phenomena. The extent of dissociation or aggregation depends on buffer type and pH and is most pronounced at alkaline pH. The variation of molecular weight of β nerve growth factor with solvent conditions is similar to that of insulin or proinsulin. Removal of either the two COOH‐terminal arginine residues or the two NH2‐terminal octapeptide sequences from the protein has no effect on its solution properties at acid pH, the protein remaining a dimer. Species such as 2‐5 S nerve growth factor or cyanogen bromide cleaved nerve growth factor which are partically deficient in COOH‐terminal arginine residues and/or NH2‐octapeptide or nonapeptide sequences are also dimers at pH40. The protein derivative which lacks the two NH2‐terminal octapeptide sequence does not, like β‐nerve growth factor, display dissociation or aggregation behavior at neutral pH, indicating that these sequences are involved in monomer‐monomer interactions.
PARTIAL PURIFICATION AND CHARACTERIZATION OF AN ACID RIBONUCLEASE IN BEEF BRAIN NUCLEI
Authors: Ittel M. E. , Niedergang C. , Munoz D. , Petek F. , Okazaki H. , Mandel P.
Published: December 2006

Abstract— In this report we describe the partial purification and characterization of an acid ribonuclease from beef brain nuclei (RNAase BN2). RNAase BN2 was purified approximately 85‐fold. The optimum pH is 6‐2 and the optimum temperature 55°C. The effect of ions on the RNAase BN2 and its Km were determined. RNAase BN2 is an endoribonuclease capable of hydrolysing polyA, polyU and polyC. Oligonucleotides produced by the hydrolysis of polyA by the RNAase BN2 have a monophosphate group at the 3′ position.
RELEASE OF [3H]GABA FROM RAT CORTICAL SLICES: NEURONAL VS GLIAL ORIGIN 1
Authors: Hammerstad J. P. , Lyte C. R.
Published: December 2006

Abstract— The effect of L‐2,4 diaminobutyric acid (DABA) and β‐alanine on the K+ stimulated release of [3H]GABA was examined using a continuous superfusion system in which a carrier mediated exchange diffusion could be demonstrated between [3H]GABA in preloaded rat cortical slices and unlabeled DABA and β‐alanine in the superfusion medium. These structurally related amino acids were chosen to investigate the source of releasable [3H]GABA because of evidence suggesting they may have differing affinities for the GABA carrier transport system that are specific for neurons and glia, DABA having a greater affinity for the neuronal GABA system and β‐alanine for the glial. Five millimolars‐DABA in the superfusion medium nearly abolished the K+ stimulated release of [3H]GABA whereas β‐alanine had little effect. The results and conclusions are discussed in terms of a postulated carrier mediated exchange of unlabeled DABA with a specific neuronal pool of [3H]GABA interfering with the K+ stimulated release of the radiolabeled GABA. The results provide indirect evidence in favor of a neuronal pool as the source of releasable [3H]GABA in this system.
THE SUBCELLULAR LOCALIZATION OF ACETYLCHOLINESTERASE AND ITS MOLECULAR FORMS IN PIG CEREBRAL CORTEX
Authors: Mclntosh C. H. S. , Plummer D. T.
Published: December 2006

Abstract— The distribution of acetylcholinesterase among the subcellular fractions of pig cerebral cortex was determined. The crude mitochondrial and microsomal fractions obtained by differential centrifugation accounted for 75% of the enzyme, with the remainder divided between the crude nuclear and soluble fractions.

The occurrence and distribution of the multiple molecular forms of AChE was the same in all four fractions with the dominant species of molecular weights 350,000, 270,000 and 60,000. Further purification of the mitochondrial fraction by density gradient centrifugation gave a series of membrane fractions with very similar multiple forms. The one possible exception was the fraction containing the purified synaptosomal membranes where one band of mol wt 270,000 predominated, although the other molecular weight entities were present. The electrophoretic pattern of AChE present in the fractionated microsomes was the same as in the crude preparation. The content and pattern of the multiple molecular forms of AChE was therefore the same in all fractions of pig brain, apart from that containing the purified synaptosomal membranes.