Reference group data for the Reitan-Indiana Neuropsychological Test Battery for Young Children.

This study presents a data set for a reference group on the Reitan-Indiana Neuropsychological Test Battery for Young Children. The data set is based on a sample of 224 children, ages 5 to 8 years, referred to a special services cooperative for academic or behavioral concerns during the years 1980 through 1993. Data are presented in terms of sample size, means, standard deviations, diagnostic classifications, and population characteristics. Previously published data sets are reviewed in comparison to this newly acquired data set. Potential advantages of this data set include the larger sample, contemporary data collection, and a sample drawn from a United States school-referred population.

Factor structure of the Reitan-Indiana Neuropsychological Battery for Children.

The Reitan-Indiana Neuropsychological Battery (RINB) was administered to a sample of children referred for educational and behavioral problems (N = 130). Subtest scores were standardized by age at 1-year intervals (6, 7, and 8 years). A principal components analysis (PCA) with promax rotation of 18 subtest scores produced a five-factor solution. Factor 1 emphasizes tactile/spatial functions, Factor 2 emphasizes concept formation and visual/spatial abilities, Factor 3 reflects motor strength, Factor 4 emphasizes sensory perception, and Factor 5 reflects motor speed. Principal factor analysis (PFA) of these data was performed to permit comparison with the PCA solutions. The PFA and PCA solutions were similar and major conclusions about factor structure were consistent.

Internal consistency of three tests from the Halstead-Reitan neuropsychological battery for older children.

The internal consistency of three neuropsychological tests was examined in a sample of 334 referred children (9-14 years of age). Coefficient alpha was calculated to estimate reliability on the Seashore Rhythm Test (SRT), two forms of the Speech Sounds Perception Test (SSPT), and the Aphasia Screening Test (AST). The standard SSPT appears to have relatively good internal consistency with an average coefficient of.81. The average coefficient for the abbreviated form of the SSPT was considerably lower (i.e.,.73), highlighting the superiority of the standard form in clinical practice. Internal consistency of the SRT was relatively low (i.e.,. 67). This level of reliability may be acceptable in group research and for component tests, but is marginal for independent clinical use. Coefficient alpha for the AST was moderate (i.e.,.77), suggesting adequate reliability for a screening test. These reliability estimates are compared to those obtained in previous studies using these tests in adult samples and with other tests commonly used with children.

Modal profiles for the Halstead-Reitan Neuropsychological Battery for Children.

Modal Profile Analysis was used to cluster students (aged 9 to 14 years) on 16 subtest scores from the Halstead-Reitan Neuropsychological Battery for Children (HRNB-C). This analysis produced eight modal profile types, all of which were replicated in multiple samples. An initial attempt to establish external validity indicated that the modal groups display dissimilar patterns of performance on independent variables. The present typology is compared to similar typologies developed with adult neuropsychological data. In sum, the current classification system provided less coverage than the adult typologies, but produced more unique or homogeneous modal groups. Discussion focuses on potential clinical and research uses of the modal HRNB-C profiles.

Factor analysis of the Intermediate Category Test.

This study examined the factor structure of the six subtests of the Intermediate Category Test in a heterogeneous sample of school-referred students, age 9 to 14 years. A three-factor solution emerged that accounted for approximately 72% of the total variance. This indicates that the test measures multiple underlying constructs in this school-referred sample. Clinical and educational interpretations may be enhanced by utilizing factor scores that reflect the multiple abilities assessed. Recommendations for developing factor/index scores are provided.

Use of the long vs short form of the speech sounds perception test in a school-age population.

A sample of 645 school-age children, ages 9 to 14 years, were administered independent forms of the Speech Sounds Perception Test for older children. 328 subjects took the complete test (SSPT-60) and 317 were administered only the first 30 items (SSPT-30). Comparison of mean errors indicated that significantly more errors were made by subjects given the SSPT-30. Decisions regarding the use of each form for school-age children are discussed.

Psychostimulant effects on neuropsychological, intellectual, and achievement measures for children and adolescents with Attention Deficit Hyperactivity Disorder.

This study compared the performance of medicated (n=57) and non-medicated (n=20) subjects with Attention Deficit Hyperactivity Disorder (ADHD) on neuropsychological, intellectual, and achievement measures. The Wechsler Intelligence Scale for Children (Revised or 3rd Edition), appropriate Halstead Reitan Neuropsychological Test Battery, and individual achievement tests were administered to subjects between the ages of 9 and 16 years (M=12.8) Initially, 26 subtest scores were analyzed using multivariate profile analysis. The two groups were found to be parallel (i e, similar in pattern of performance) and coincident (i.e., similar in level of performance). This suggests that the subjects in the two groups displayed a similar pattern of performance on these neuropsychological, intellectual, and achievement measures. The results are discussed in relation to previous research, current etiological models, and the assessment and treatment of ADHD.

Electron spin resonance spectroscopy does not reveal hydroxyl radical production in activated natural killer lymphocytes.

We investigated hydroxyl radical (OH) production by human natural killer (NK) cells, using electron spin resonance (ESR) spectroscopy and 5.5 dimethyl-1-pyrroline-N-oxide (DMPO), a spin trap specific for OH. production. We confirmed that hydroxyl radical scavengers, n-propyl gallate and catechin, inhibited NK cell-mediated cytotoxicity (NK-CMC) in a dose-dependent manner and demonstrated that DMPO also inhibited NK-CMC. Polymorphonuclear leukocytes (PMNL) activated by opsonized zymosan (2.4 mg/ml) and mixed with DMPO (0.14 M) showed an early increase in hydroxyl radical production, leading to a net production of free radical of almost 400 pMol/10(6) cells. We then mixed NK cells with K562, an NK-sensitive tumor cell, at a 1:1 ratio and added DMPO (0.14 M). We pelleted the cells to increase EC to TC binding before taking the sample readings. Activated NK cells showed no increase in OH. production, leading to a net production of free radicals less than 1% that of activated PMNL. These data strongly suggest that hydroxyl radical production does not play a role in the early events of NK cell activation; they indicate a need to reevaluate the mechanism of inhibition of NK-CMC by OH. scavengers.

Degradation of gonococcal peptidoglycan by granule extract from human neutrophils: demonstration of N-acetylglucosaminidase activity that utilizes peptidoglycan substrates.

The degradation of purified Neisseria gonorrhoeae peptidoglycan (PG) by granule extract derived from normal human polymorphonuclear leukocytes was examined. Hen egg lysozyme-resistant, extensively O-acetylated [3H]PG (O-PG) from strain FA19 and lysozyme-sensitive, non-O-acetylated [14C]PG (non-O-PG) from strain RD5 (each containing label in both glucosamine and muramic acid) were mixed and incubated with granule extract at pHs 4.5, 5.5, and 6.5. The rate of degradation of O-PG was uniformly slower than that of non-O-PG in the same tube, but ultimately, even the O-PG was rendered completely soluble. Molecular-sieve high-performance liquid chromatography revealed that both PGs were degraded by granule extract at the pH values tested to disaccharide peptide monomers and peptide-cross-linked oligomers, reflecting the action of human lysozyme. Of particular interest was the appearance of a peak containing free N-acetylglucosamine which was quite prominent in reaction mixtures at pH 4.5, less prominent at pH 5.5, and not detectable at pH 6.5. Free N-acetylglucosamine was not released from control PG samples at any pH in the absence of granule extract. Treatment of purified gonococcal PG monomers with granule extract at pH 4.5 yielded exclusively free N-acetylglucosamine and muramyl peptides with no N-acetylglucosamine. These data suggest that granule extract contains a previously undescribed pH-dependent N-acetylglucosaminidase with specificity for PG as well as an N-acetylmuramidase activity that degrades O-PG less efficiently than it does non-O-PG.

Effect of vitamin E on FMLP-induced activation of rabbit polymorphonuclear leukocytes.

Granulocytes of vitamin E-treated rabbits were compared to granulocytes from placebo-treated rabbits. Granulocytes were isolated from rabbit peripheral blood by a new method employing Percoll and gelatin sedimentation. Vitamin E-treated cells showed less adherence to rabbit aortic endothelium when stimulated with FMLP. FMLP receptor numbers and affinity were not significantly different. Resting cell surface and baseline transmembrane potential were similar in both cell types. Decrease in cell surface potential with FMLP was comparable in vitamin E- and placebo-treated cells. Vitamin E-treated PMN depolarized more and hyperpolarized more rapidly than placebo cells. Thus vitamin E-treated PMNs show differences in the early events of PMN activation. These may contribute to the lower stimulated adherence observed with vitamin E-treated cells.

Glycoprotein-180 deficiency: genetics and abnormal neutrophil activation.

Neutrophil function was studied in a patient with polymorphonuclear leukocyte (PMN) glycoprotein-180 deficiency and in her parents. PMNs of the patient had abnormal chemotaxis, phagocytosis, adherence, surface charge, and membrane-associated events of activation. Selective defects to C3b, immunoglobulin G (IgG), phorbol myristate acetate (PMA) and N-formyl-methionyl-leucyl-phenylalanine (FMLP) are described, although C3b receptor density was normal. The parents were found to have abnormal adherence to nylon-wool fibers, abnormal transmembrane potential depolarization with PMA, and reduced amounts of glycoprotein-180 in their PMNs. These studies provide further evidence that the oxidative burst has several different pathways for activation. They demonstrate that the absence of a single PMN surface glycoprotein is associated with a broad spectrum of PMN functional abnormalities. Finally, the observations made in the parents support an autosomal recessive mode of inheritance.

Comparative responses of human polymorphonuclear leukocytes obtained by counterflow centrifugal elutriation and Ficoll-Hypaque density centrifugation. II. Membrane potential changes, membrane receptor analysis, membrane fluidity, and analysis of the effects of the preparative techniques.

Standard preparative techniques for human polymorphonuclear leukocytes involves the sequential exposure of the PMN to dextran, Ficoll-Hypaque (FH) gradient centrifugation, and hypotonic stress. Counterflow centrifugal elutriation (CCE) allows isolation of PMN from whole blood without exposure to these potentially toxic substances. We have previously reported that PMN isolated by CCE release more superoxide on stimulation than do PMN isolated by standard techniques (FH PMN). In this report, we extend these observations and show that CCE and FH PMN have similar binding kinetics for the chemotactic peptide N-formyl-methionyl-leucyl-phenylalanine (FMLP) and similar membrane fluidity. CCE PMN, however, were noted to have a more marked membrane depolarization on stimulation with FMLP than FH PMN. We show that exposure of purified CCE PMN to dextran increases their superoxide release on stimulation, as well as the available FMLP binding sites. Exposure of FH PMN to elutriation buffer increased their superoxide release on stimulation. It was also noted that both CCE and FH PMN re-exposed to FH increased available binding sites for FMLP. The possible reasons for these findings are discussed.

Membrane-bound lactoferrin alters the surface properties of polymorphonuclear leukocytes.

Polymorphonuclear leukocytes (PMN) aggregate and avidly attach to endothelium in response to chemotactic agents. This response may be related in part to the release of the specific granule constituent lactoferrin (LF). We found by using immunohistology and biochemical and biophysical techniques that LF binds to the membrane and alters the surface properties of the PMN. Upon exposure of PMN treated with 5 micrograms/ml cytochalasin B to 2 x 10(-7) M formyl-methionine-leucine-phenylalanine for 5 min, the PMN mobilized LF to their surface as observed by immunoperoxidase staining for LF. At added LF levels ranging from 4 to 15 micrograms/10(7) PMN there was a dose-dependent reduction in PMN surface charge reaching 4 mV, when the partitioning into the membrane of a charged amphipathic nitroxide spin label was measured by electron spin resonance spectroscopy, whereas transferrin was without effect. When 125I-FeLF was added to human PMN in increasing amounts and the results corrected for the residual amount of free LF contaminating the cells, the PMN were saturated with LF at concentrations between 100 and 200 nM in the medium. Human PMN bound 1.35 x 10(6) molecules per cell and the calculated value for the association constant for these receptors was 5.2 x 10(6) M-1. Additionally, 6 micrograms/ml LF served as an opsonin for rabbit MN to promote PMN uptake by rabbit macrophages, when assessed by electron microscopy, but lysozyme did not. These studies indicate that LF can bind to the surface of the PMN and reduce its surface charge. This correlates with enhanced "stickiness" leading to a variety of cell-cell interactions.

The influence of vitamin E on human polymorphonuclear cell metabolism and function.

These studies on the effect of administration of 1,600 units of vitamin E to humans indicated the following responses to the PMNs (TABLE 6). Functional alterations occur with an increased ability to ingest particles but a mild decrease in bactericidal potency of the PMN. Although the respiratory burst is slightly enhanced as is superoxide anion release, H2O2 release from the PMN is markedly impaired. The hexose monophosphate shunt activity, which is dependent on intracellular H2O2 is decreased during phagocytosis. Membrane responses such as changes in order parameter during phagocytosis as reported by the stearic acid analogue probe 5DS are similar to those of normal PMNs. The release of arachidonic acid from membranes of vitamin E PMNs during phagocytosis of opsonized zymosan is slightly enhanced, indicating normal phospholipase A2 activation. NADH oxidase-derived H2O2 is not impaired within phagocytic generated by NADPH oxidase in phagocytic vesicles, accounting for impairment in HMPS activity and bactericidal activity in these cells.

Membrane fluidity changes accompanying phagocytosis in normal and in chronic granulomatous disease polymorphonuclear leukocytes.

We have studied membrane fluidity changes in polymorphonuclear leukocytes (PMN) during phagocytosis. Membrane fluidity was assessed by electron spin resonance (ESR) using a nitroxide-substituted stearic acid analog (5DS) as a spin probe. PMN from normal subjects and from 3 CGD patients (2 males, 1 female) were incubated in Kreb's Ringers phosphate with or without opsonized zymosan. ESR spectra were obtained and the order parameter (S), which is inversely related to membrane fluidity, was calculated. Without zymosan addition, S for normal (0.638) and for CGD (0.635) were not significantly different (p less than 0.35). The S values indicate that under resting conditions the molecular environment of the CGD membrane is similar to that of normal PMN membranes. However, with addition of opsonized zymosan, the normal, but not the CGD, PMN showed a significant increase (CGD, S = 0.638; normal, S = 0.647; p less than 0.001). This change in S for the normals is consistent with a more restricted movement of 5DS. Treatment of normal PMN with a mixture of scavengers specific for H2O2 (catalase, 1600 U/ml), O2-.(superoxide dismutase, 100 micrograms/ml), and for HO., (sodium benzoate, 1mM) during zymosan stimulation gave S values similar to those of resting cells. Catalase alone also lowered S value, suggesting that H2O2 was instrumental in causing the initial S value increase. This idea was supported by studies in which CGD cells were incubated with zymosan in the presence of glucose oxidase, an enzyme that catalyzes glucose oxidation resulting in the direct reduction of molecular oxygen to H2O2. Our results indicate that reduced O2 by-products, particularly H2O2, can cause altered biophysical properties of PMN membrane during phagocytosis.

Fluidity properties and liquid composition of erythrocyte membranes in Chediak-Higashi syndrome.

We have earlier shown through electron spin resonance (ESR) studies of leukocytes that membranes of cells from both Chediak-Higashi syndrome (CHS) mice and humans have abnormally high fluidity. We have extended our studied to erythrocytes. Erythrocytes were labeled with the nitroxide-substituted analogue of stearic acid, 2-(3-carboxypropyl)-4,4-dimethyl-2-tridecyl-3-oxazolidinyloxyl, and ESR spectra were obtained. Order parameter, S, at 23 degrees C, was 0.661 and 0.653 for erythrocytes of normal and CHS mice (P less than 0.001). S was 0.684 for normal human erythrocytes and 0.675 (P less than 0.001) for CHS erythrocytes at 25 degrees C. Because S varies inversely to fluidity, these results indicate that CHS erythrocytes tend to have higher fluidity than normal. In vitro treatment of both mice and human CHS erythrocytes with 10 mM ascorbate returned their membrane fluidity to normal. We prepared erythrocyte ghosts and extracted them with CHCl3:CH3OH (2:1). Gas-liquid chromatography analysis showed a greater number of unsaturated fatty acids for CHS. The average number of double bonds detected in fatty acids for mice on a standard diet was 1.77 for normal and 2.02 for CHS (P less than 0.04); comparison of human erythrocytes from one normal control and one CHS patient showed a similar trend. Our results suggest that an increased proportion of unsaturated fatty acids may contribute to increased fluidity of CHS erythrocytes. Our observation that both leukocytes and erythrocytes of CHS have abnormal fluidity indicates that CHS pathophysiology may relate to a general membrane disorder.

Resolution of basic gonococcal outer membrane proteins by nonequilibrium pH gradient electrophoresis.

Outer membrane proteins from opaque and transparent colonial variants of strain F62 of Neisseria gonorrhoeae were analyzed by two-dimensional electrophoresis with isoelectric focusing in the first dimension and sodium dodecyl sulphate-polyacrylamide gel electrophoresis in the second. Most of the higher-molecular-weight proteins focused sharply in the acidic region of the gel. In contrast, the principal outer membrane protein, a 31,000-molecular-weight protein, and the opacity-associated proteins remained near the origin (at the basic end of the gel) without focusing. However, when the samples were loaded on the acidic end of an isoelectric focusing gel and subjected to nonequilibrium pH gradient electrophoresis, these proteins behaved as basic proteins. In addition, three distinct opacity-associated heat-modifiable proteins could be identified. No other differences in the protein composition of outer membranes from opaque and transparent variants were apparent. Amino acid analysis of the principal outer membrane protein indicated that its net positive charge may result from partial amidation of its acidic residues. The unexpected observation that the major surface proteins of the gonococcus are basic may have implications for intragonococcal adhesion and for gonococcal interactions with mammalian cells.

Cross-linking analysis of the outer membrane proteins of Neisseria gonorrhoeae.

The organization of outer membrane proteins of Neisseria gonorrhoeae was investigated by using two-dimensional dodecyl sulfate-polyacrylamide gel electrophoresis and cross-linking agents. A naturally occurring protein aggregate, which may be composed of two proteins of 50,000 molecular weight, was detected in all strains. Treatment of whole cells with cross-linking agents yielded several additional complexes, suggesting that other proteins are arranged in the outer membrane as near neighbors. The principal outer membrane protein (molecular weight, 34,000) cross-linked (i) to itself to form a complex whch appeared to be trimeric, (ii) to the 28,000-molecular-weight outer membrane protein to form a bimolecular comlex, and (iii) to the 28,000-molecular-weight outer membrane protein in a 3:1 ratio. The formation of these complexes was independent of (i) colony type, (ii) colony opacity, (iii) pH during growth, and (iv) presence of markers for drug resistance or hypersensitivity.

High-molecular-weight antigenic protein complex in the outer membrane of Neisseria gonorrhoeae.

The outer membrane of Neisseria gonorrhoeae contains approximately 15 proteins, with 2 or 3 accounting for over 75% of the total protein mass. Samples of outer membrane from strain 2686 T4 analyzed by electrophoresis in 2% polyacrylamide gels revealed a band with an apparent molecular weight of 800,000. The band was protein material, as indicated by trypsin and pronase sensitivity and by L-[3H]proline incorporation. Peptidoglycan, nucleic acids, and carbohydrate were not detected in the band. Dye binding, L-[3H]proline incorporation, and labeling of solubilized outer-membrane proteins with 125I-labeled Bolton-Hunter reagent indicated that the band made up 10 to 13% of the total protein mass of isolated outer membranes. The material in the band was purified by gel filtration and, after reduction and alkylation, quantitatively recovered as subunits with an apparent molecular weight of 76,000. The protein in complex form was exposed at the cell surface, as evidenced by labeling whole cells with 125I by using a lactoperoxidase-catalyzed reaction and with CNBr-activated dextran. Rabbit serum raised against whole 2686 T4 gonococci contained antibody which reacted with the protein complex. The protein complex was detected in all gonococcal strains tested, but its presence could not be demonstrated in several other gram-negative species.