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Biomedical subjects

S L Harris

Publications and source records attributed to S L Harris.

At least 55 records · Page 3Linked to original sources
PubMed1991

Hardiness and social support as predictors of psychological discomfort in mothers of children with autism.

Mothers of 60 children with autism participated in this study to measure the effects of social support and hardiness on the women's responses to the stressful demands of raising a child with a disability. MANOVA analysis indicated a significant main effect for hardiness, Wilks' lambda = .859, approx. F(2, 55) = 4.494, p less than .02. There were no main effects for social support, or for the interaction of social support and hardiness. In regression analyses, the best combination of predictors of depressive symptoms were the Commitment dimension on the Hardiness Questionnaire and the total score on the Interpersonal Support Evaluation List social support inventory, mult. R = .783, p less than .001. The best predictor of somatic complaints was total Hardiness score, mult. R = .698, p less than .01. There was a significant correlation between hardiness and perceived social support, r(57) = -.67, p less than .001. Results are discussed in terms of the relationship between perceived social support and hardiness and the potential buffering effect of these dimensions.

Adaptation, Psychological↗
PubMed1991

Changes in cognitive and language functioning of preschool children with autism.

Preschool children with autism and their normally developing peers were compared on the Stanford-Binet IV and Preschool Language Scale before and after 1 school year. Both measures showed that although the children with autism functioned at a lower level than their normally developing peers, the children with autism had narrowed this gap after treatment, making a nearly 19-point increase in IQ and an 8-point gain in language quotient. The IQ measure remained stable for the normally developing peers while their language showed a 7.73-point increase. The data support the notion that young children with autism can make very significant developmental gains.

Autistic Disorder↗
PubMed1991

Does punishment hurt? The impact of aversives on the clinician.

This paper explored the extent to which the use of mild versus strong aversives in programs for clients with autism affected the degree of job stress reported by direct care staff on the Maslach Burnout Inventory. The subjects included 56 staff from programs using only mild aversives and 60 staff from programs using strong aversives. Subjects anonymously completed the inventory and mailed it directly back to the researchers. The most significant finding was that direct care staff in facilities which permitted the use of strong aversives reported more intense feelings of personal accomplishment on the inventory than did subjects whose programs were limited to the use of mild aversives. Furthermore, there was a significant relationship among the personal use of strong aversives, number of years in the field, and the intensity of Personal Accomplishment. These findings suggest that allowing staff to use a wide range of interventions including strong aversives may diminish job stress and enhance one's sense of personal efficacy.

Adolescent↗
PubMed1990

Changes in language development among autistic and peer children in segregated and integrated preschool settings.

Five young children with autism enrolled in a segregated class, five other children with autism in an integrated class, and four normally developing peer children in the integrated class were compared for developmental changes in language ability as measured by the Preschool Language Scale before and after training. The results, based on Mann-Whitney U tests, showed that (a) all of the children as a group made better than normative progress in rate of language development, (b) the scores of the autistic children were significantly lower than the peers before and after treatment, and (c) there were no significant differences in changes in language ability between the autistic children in the segregated and integrated classes.

Autistic Disorder↗
PubMed1990

Glycoprotein C of herpes simplex virus type 1 prevents complement-mediated cell lysis and virus neutralization.

Glycoprotein gC1 of herpes simplex virus type 1 (HSV-1) binds complement component C3b. To determine if gC1 modifies the interaction of complement with virus-infected cells or cell-free virus, ns-1, a mutant HSV-1 strain that does not express gC1 at the cell surface and does not bind C3b, was compared with its parental strain, NS. Cells infected with the gC1 mutant were more susceptible to cytolysis mediated by antibody and complement or complement alone. The gC1 or gD1 genes were expressed in mammalian cells under the control of an inducible promoter. Cells induced to express gC1 resisted complement cytolysis, while cells expressing gD1 did not. gC1 modified cytolysis of virus-infected or -transfected cells by blocking alternative complement pathway activation. gC1 also modified complement-dependent virus neutralization, which was mediated by inhibiting the classical complement pathway. These results indicate a protective role for gC1 on the virion and at the cell surface.

Antibody-Dependent Cell Cytotoxicity↗
PubMed1990

Effect of type 1 piliation on in vitro killing of Escherichia coli by mouse peritoneal macrophages.

Escherichia coli K-12 mutants possessing defined lesions affecting type 1 pilus production, receptor binding, or length were examined for their ability to resist killing by mouse peritoneal macrophages in vitro. Mutants were mixed pairwise at known ratios in wells containing macrophages, and after incubation, the ratio of the survivors was assayed. The difference in phagocytic killing between type 1 piliated cells and isogenic nonpiliated cells was significant, the piliated cells being approximately threefold more resistant. Pilus length had little effect upon survival, as the long-piliated mutants were no more resistant to killing than the normal-length parents. Interestingly, the receptor-binding function of type 1 pili was most important in effecting resistance, as mutants lacking the ability to bind receptor were killed as effectively as nonpiliated mutants. These data are consistent with the notion that pili actually impede killing by macrophages rather than serve as passive physical barriers to uptake.

Animals↗
PubMed1990

Isolation and characterization of mutants with lesions affecting pellicle formation and erythrocyte agglutination by type 1 piliated Escherichia coli.

The product of the pilE (also called fimH) gene is a minor component of type 1 pili in Escherichia coli. Mutants that have insertions in the pilE gene are fully piliated but unable to bind to and agglutinate guinea pig erythrocytes, a characteristic of wild-type type 1 piliated E. coli. In this paper we describe the isolation of 48 mutants with point lesions that map to the pilE gene. Such mutants were isolated by using mutT mutagenesis and an enrichment procedure devised to favor the growth of individuals that could form a pellicle in static broth containing alpha-methylmannoside, an inhibitor of erythrocyte binding and pellicle formation. Results indicated that the enrichment favored mutants expressing pilE gene products that were defective in mediating erythrocyte binding. Characterization of 12 of the mutants in greater detail revealed that certain lesions affected pilus number and length. In addition, a mutant that was temperature sensitive for erythrocyte binding was isolated and used to provide evidence that pellicle formation relies on the intercellular interaction of pilE gene products. Our results suggest a molecular explanation for the old and paradoxical observations connecting pellicle formation and erythrocyte agglutination by type 1 piliated E. coli.

Alleles↗
PubMed1990

Teaching youths with autism to offer assistance.

Three adolescent boys with autism were taught to offer assistance to a person stating inability to complete a task. The study used a multiple baseline across the 3 youths and a multiple baseline across three tasks for each student. Both designs provided clear support for the ability of the youths to discriminate those settings in which offers of assistance were desired. All 3 participants showed relatively rapid acquisition of responding. Generalization was assessed to a new person in the training setting, to a familiar person in a new room at the center, to the mother in the youth's home, and to three novel tasks. Generalization to a new person in the familiar setting was most likely to occur, with very high levels of responding for all 3 youths. Generalization to the other conditions varied across youths, although all 3 boys showed some transfer of skills to all conditions.

Adolescent↗
PubMed1990

Traumatic dislocation of the crystalline lens with delayed total retinal detachment.

Traumatic dislocation of the crystalline lens usually presents as a visual disturbance that can often be corrected by nonsurgical means. However, this ocular condition is fraught with serious complications that can occur years later. The two most serious complications are glaucoma and retinal detachment. These complications can make treatment of patients with traumatic lens dislocation a dilemma for the optometrist and ophthalmologist alike.

Cryosurgery↗
PubMed1989

Defective H(+)-ATPase of hygromycin B-resistant pma1 mutants fromSaccharomyces cerevisiae.

Mutations in the plasma membrane H(+)-ATPase gene (PMA1) of Saccharomyces cerevisiae that confer growth resistance to hygromycin B have been shown recently to cause a marked depolarization of whole cell membrane potential (Perlin, D. S., Brown, C. L., and Haber, J. E. (1988) J. Biol. Chem. 263, 18118-18122). In this report, the biochemical and genetic properties of H+-ATPases from four prominent hygromycin B-resistant pma1 mutants, pma1-105, pma1-114, pma1-147, and pma1-155, are described. Single base pair changes were identified in pma1-105, pma1-114, and pma1-147 that resulted in amino acid substitutions of Ser-368----Phe, Gly-158----Asp, Pro-640----Leu, respectively. An A----G transition mutation at -39 in the 5'-untranslated region of the mRNA of pma1-155 was also found. This mutation creates an out-of-Frame upstream AUG initiation codon that apparently reduces normal translation of PMA1. DNA sequence analysis of PMA1 from strain Y55 identified 9 base pair substitutions that resulted in 6 amino acid changes in nonconserved regions when compared to the published sequence for strain S288C. Plasma membranes of three of the four pma1 mutants contained normal amounts of H(+)-ATPase; membranes from pma1-155 contained enzyme at 62% of the wild-type level. The kinetics of ATP hydrolysis were most strongly altered for enzymes from pma1-105 and pma1-147 which showed changes in both Km and Vmax. A striking pH dependence for these parameters was found for enzyme from pma1-105 which resulted in a precipitous decline in Km and Vmax below pH 6.5. ATP hydrolysis by enzymes from pma1-105 and pma1-147 was insensitive to inhibition by vanadate. These enzymes, in contrast to wild-type and vanadate-sensitive mutant enzymes, were poorly protected from trypsin-induced inactivation by MgATP and vanadate or Pi alone. These results are pertinent to the mechanism of vanadate-induced enzyme inhibition and suggest that Ser-368 and Pro-640 influence the affinity of the phosphate-binding site for Pi. All mutant enzymes catalyzed ATP-induced pH gradient formation following purification and reconstitution into liposomes. Finally, these results further demonstrate the usefulness of hygromycin B as a generalized screening tool for isolating diverse plasma membrane ATPase mutants.

Alleles↗
PubMed1989

Clinical experience with HIV-infected patients at the University of Oklahoma Health Sciences Center.

Two hundred seventy-two patients infected with human immunodeficiency virus (HIV) have received care from the members of the adult infectious disease section at the University of Oklahoma Health Sciences Center. The majority of these patients met the diagnostic criteria for acquired immunodeficiency syndrome. This group of patients was characterized by relatively few parenteral drug abusers, a high incidence of disseminated histoplasmosis, and an unexpectedly low frequency of toxoplasmosis. The prevalence of risk behaviors and endemic disease may be responsible for these particular case distributions.

Acquired Immunodeficiency Syndrome↗
PubMed1987

Plantar motoneuron columns in the rat.

In the rat, the numbers and locations of motoneurons innervating the short plantar muscles of the hindlimb (supplied by the medial and lateral plantar nerves, as well as a branch of the sural nerve) were determined by using both horseradish peroxidase (HRP) and fluorochromes as retrograde labels. Topographical organization within the plantar motor nucleus was examined by exposing individually the cut ends (encapsulated in low melting-point paraffin) of medial plantar, lateral plantar, and sural nerves to HRP. In addition, double-labeling experiments were conducted in which the medial plantar nerve was labeled with one fluorochrome (either true blue or diamidino yellow) and the lateral plantar nerve with another. The plantar motor pool is located in the extreme dorsolateral portion of the ventral horn, usually concentrated in the fifth lumbar (L5) spinal segment. Labeled motoneurons extended caudally into the sixth lumbar (L6) segment and rostrally into portions of the fourth lumber (L4) segment. Motoneurons of the medial plantar, lateral plantar, and sural nerve have overlapping territories. Sural motoneurons (about 70 cells per side) are generally confined to L5, medial plantar motoneurons (about 180 cells per side) tend to be concentrated in caudal L5 and rostral L6, whereas the lateral plantar motoneurons (about 310 cells per side) extend throughout the entire length of the plantar motor pool. The distribution of motoneuronal cell size is unimodal (mean cross-sectional area = 610 +/- 150 microns2). Cell bodies of plantar motoneurons tend to have similar geometries in all three major planes of sectioning. In all, the combined plantar plus sural nerve population amounts to about 560 motoneurons on each side of the spinal cord. On the basis of these data, and those published by others, the innervation of the small muscles of the foot accounts for about 25% of the motor axons carried by the entire sciatic nerve.

Animals↗
PubMed1986

Binding of complement component C3b to glycoprotein gC of herpes simplex virus type 1: mapping of gC-binding sites and demonstration of conserved C3b binding in low-passage clinical isolates.

The sites on glycoprotein gC of herpes simplex virus type 1 (HSV-1) which bind complement component C3b were evaluated by using anti-gC monoclonal antibodies and mutants which have alterations at defined regions of the glycoprotein. Monoclonal antibodies were incubated with HSV-1-infected cells in a competitive assay to block C3b binding. Each of 12 different monoclonals, which recognize the four major antigenic sites of gC, completely inhibited C3b binding. With this approach, no one antigenic group on gC could be assigned as the C3b-binding region. Next, 21 gC mutants were evaluated for C3b binding, including 1 which failed to synthesize gC, 4 which synthesized truncated forms of the glycoprotein such that gC did not insert into the cell's membrane, and 16 which expressed gC on the cell's surface but which had mutations in various antigenic groups. Eleven strains did not bind C3b. This included the 1 strain which did not synthesize gC, the 4 strains which secreted gC without inserting the glycoprotein into the cell membrane, and 6 of 16 strains which expressed gC on the cell surface. In these six strains, the mutations were at three different antigenic sites. One hypothesis to explain these findings is that C3b binding is modified by changes in the conformation of gC which develop either after antibodies bind to gC or as a result of mutations in the gC gene. Attachment of C3b to gC was also evaluated in 31 low-passage clinical isolates of HSV-1. Binding was detected with each HSV-1 isolate, but not with nine HSV-2 isolates. Therefore, although mutants that lack C3b binding are readily selected in vitro, the C3b-binding function of gC is maintained in vivo. These results indicate that the sites on gC that bind C3b are different from those that bind monoclonal antibodies, that antibodies directed against all sites on gC block C3b binding, and that C3b binding is a conserved function of gC in vivo.

Antibodies, Monoclonal↗
PubMed1985

Parents and grandparents view the autistic child.

Mothers, fathers, grandmothers, and grandfathers of 19 autistic children completed a questionnaire describing their view of the handicapped child, the impact of the child on the parent, and the relationship between the parents and grandparents. Paired t tests revealed that whenever there was a significant difference between the generations, grandparents took a more positive view. For example, maternal grandmothers had a more positive view of the child than did their daughters, and paternal grandmothers had a more positive view of their relationship with their son than did the son. Grandmothers demonstrated an empathic understanding of their daughter's experiences. There was a significant Pearson product-moment correlation between grandmothers and grandfathers in overall scores, their view of the child, and how they viewed their son's or daughter's experiences as the parent of a handicapped child. Maternal grandparents visited the family significantly more often than paternal grandparents. The study offers us a first empirical look at grandparents and their autistic grandchild.

Adult↗
PubMed1984

Teaching of labels: an analysis of concrete and pictorial representations.

The relationship between the use of concrete objects and pictorial representations of those objects when teaching noun labels to 3 autistic boys was analyzed. A multiple baseline design, counterbalanced for the type of stimulus presentation, was used to teach four sets of five objects and their pictorial representations to the youngsters. Although results indicated no consistent functional relationship between the two types of stimulus presentation, there were varying degrees of generalization between the two conditions. Findings suggest that there is a need to facilitate greater and more consistent generalization from pictures to the realities they represent.

Autistic Disorder↗