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Biomedical subjects

L Ross

Publications and source records attributed to L Ross.

At least 19 recordsLinked to original sources
PubMed1995

Psychometric characteristics of revised Sociotropy and Autonomy Scales in college students.

Beck, Epstein, Harrison and Emery (unpublished manuscript, 1983) developed the Sociotropy-Autonomy Scale (SAS) to assess personality constructs that were considered possible vulnerability factors to reactive depression. Principal components and factor analyses of an expanded 93-item version of the SAS were performed with successive samples of undergraduates totalling 2041 Ss. Only 59 items were needed to establish the generalizabilities of one dimension of Sociotropy and two dimensions of Autonomy. Three subscales reflecting Sociotropy, Solitude and Independence were constructed from these items. The convergent and discriminant validities of the three subscales were assessed with respect to a variety of other psychological tests. The overall pattern of relationships indicated that Solitude was positively correlated with dysphoria, perfectionism, self-criticalness, and loneliness. In contrast, Independence was positively correlated with perfectionism and self-efficacy, but inversely related to concern about approval from others. Sociotropy was correlated with dependency, self criticalness, and affiliation motivation. The findings supported the construct validity of the three revised SAS subscales.

Adjustment Disorders↗
PubMed1995

Dexamethasone therapy for children with bacterial meningitis. Meningitis Study Group.

OBJECTIVE: To determine whether treatment with dexamethasone and ceftriaxone for children with bacterial meningitis reduces the frequency of either sensorineural hearing loss or other neurologic sequelae. DESIGN: This was a prospective, multicentered, placebo-controlled clinical trial. Subjects were followed for 1 year. SETTING: The study was conducted in six children's hospitals located in Pittsburgh, Houston, Los Angeles, Chicago, Washington, D.C., and Columbus, Ohio. PATIENTS: Enrolled were 173 children, 8 weeks to 12 years of age, with suspected bacterial meningitis; 143 children were evaluable. Eighty-seven percent of patients were followed for at least 6 weeks to 3 months, and 67% were followed for 1 year. INTERVENTIONS: Subjects were randomized to receive ceftriaxone with or without dexamethasone (0.15 mg/kg every 6 hours for 4 days). Auditory brainstem responses (ABR) were measured within 24 hours of admission. MAIN OUTCOME MEASURES: Hearing, development, and neurologic sequelae were assessed at the time of discharge and 6 weeks and 1 year later. MAIN RESULTS: One hundred forty-three patients (69 received dexamethasone and 74 received placebo) with bacterial meningitis were evaluable: Haemophilus influenzae type b (83), Streptococcus pneumoniae (33), Neisseria meningitidis (24), and three others. Overall, there was no significant difference in auditory outcome between dexamethasone and placebo recipients. Twenty-two children had bilateral moderate or more severe hearing loss at the time of the first ABR. At follow-up, the resolution of hearing impairment was nearly identical for each group. Nine of ten children who remained persistently deaf were deaf at the time of the first ABR. There were no differences in neurologic or developmental outcome between groups. CONCLUSION: All but one child with persistent bilateral moderate or more severe hearing loss had demonstrable deafness at the time of the first ABR. Dexamethasone did not significantly improve audiologic, neurologic, or developmental outcome in children with bacterial meningitis.

Ceftriaxone↗
PubMed1994

A truncated recombinant intercellular adhesion molecule-1 inhibits adhesion of leukemic cell lines to upregulated endothelial cells.

Intercellular adhesion molecule-1, a member of the immunoglobulin supergene family, is the ligand for the integrin lymphocyte function associated antigen-1. Intercellular adhesion molecule-1 and lymphocyte function associated antigen-1 binding interactions mediate leukocyte adherence and migration. Previous work has shown that the adherence of lymphocyte function associated antigen-1 is directed to the first immunoglobulinlike domain of the endothelial cell surface protein intracellular adhesion molecule-1. We have constructed a truncated intercellular adhesion molecule-1 gene encoding the first 185 amino acids from the amino terminus and overexpressed it in Escherichia coli. The recombinant protein was purified from insoluble inclusion bodies and refolded into an active conformation by a denaturation/renaturation cycle. The identity of the protein was confirmed by microsequencing and by Western blot analysis using a polyclonal antibody to ICAM-1. We have demonstrated that this soluble region of the otherwise membrane-bound ligand is an inhibitor of Molt or HL-60 cell adhesion to cytokine-stimulated endothelial cells.

Amino Acid Sequence↗
PubMed1994

Depressive disorders and suicidal intent in adolescent suicide attempters.

This study describes the relationships between the presence of a depressive disorder, suicidal intent, and the medical seriousness of a suicide attempt in an adolescent sample. Consecutive adolescents who attempted suicide were evaluated for the presence or absence of current DSM-III-R depressive disorders (DD). Adolescent suicide attempters with DD were compared with those without DD regarding the level of their suicide intent and the medical seriousness of their suicide attempt. Adolescent suicide attempters with a diagnosis of DD were found to have a higher level of suicidal intent than were those without depressive illness. There was no relationship between the medical seriousness of the suicide attempt and the presence of DD. Clinicians should specifically assess for DSM-III-R DD as a means of determining suicidal intent in adolescent suicide attempters.

Adolescent↗
PubMed1992

Inhibition of Molt-4-endothelial adherence by synthetic peptides from the sequence of ICAM-1.

Previous studies have shown that inflammatory pathologies are mediated by lymphocyte adhesion to endothelium and subsequent transmigration through the endothelial monolayer. Lymphocyte-endothelial adherence is, in part, caused by the leukocyte integrin LFA-1 binding to ICAM-1, its ligand on endothelial cells. Synthetic peptides based on specific amino acid sequences of human ICAM-1 inhibit the adherence of a lymphocytic cell line, Molt-4, to cytokine-stimulated endothelial cells. A total of 26 peptides spanning the extracellular domains of ICAM-1 were evaluated for their inhibitory activity in two cell adhesion assays. Binding of fluorescently labeled Molt-4 cells to TNF-stimulated human umbilical vein endothelial cells was inhibited reproducibly by peptides ICAM1-20, ICAM26-50, ICAM40-64, ICAM132-146, and ICAM345-375. Three overlapping sequences of the peptide ICAM40-64, KELLLPGNNRKVYELSNVQEDSQPM, were synthesized and tested as well, and the sequence KELLLPGNNRKV showed the greatest inhibition. The inhibitory activity of these peptides was confirmed using a second assay, inhibition of aggregation of the Epstein-Barr virus-transformed B-lymphoblast line JY. Polyclonal antibodies were developed in rabbits by immunization with two of the peptides and characterized for their ability to inhibit lymphocyte-endothelial adherence. These studies predict potential sites for interaction of the integrin receptor, LFA-1, with its ligand, ICAM-1. Thus lymphocyte-endothelial interaction, and resulting inflammation, may be partially mediated by the association of ICAM-1 with LFA-1 at the specific molecular locations identified in this study.

Amino Acid Sequence↗
PubMed1992

Neuroblastoma masquerading as a retroperitoneal Salmonella abscess.

Symptomatic Salmonella infections usually manifest as self-limited gastrointestinal distress. Patients with chronic systemic illnesses or those who are immunosuppressed may rarely present with Salmonella infection as distant suppurative abscesses. We present a previously healthy Armenian boy who came to medical attention with abdominal pain, fever, and anemia. Abdominal computed tomography (CT) scan showed a cystic suprarenal mass that was surgically explored and found to be a retroperitoneal Salmonella abscess. Postoperative CT scan showed resolving inflammation. A 6-month follow-up CT showed a large suprarenal tumor, which at exploration was found to be neuroblastoma. To our knowledge, Salmonella has never been reported presenting as a solitary retroperitoneal abscess, and neuroblastoma has not been described presenting as a Salmonella abscess. The patient is also unusual because the abscess contained a species unusual for suppurative salmonellosis.

Abscess↗
PubMed1990

Ear wax removal: a survey of current practice.

OBJECTIVE: To determine the methods of removing ear wax used by local general practitioners and the incidence of associated complications. DESIGN: Postal survey of 312 general practitioners serving a population of about 650,000; supplementary study of ear, nose, and throat outpatients to quantify the improvement in aural acuity after wax removal. SETTING: Catchment area of the Edinburgh otolaryngological unit. PARTICIPANTS: 289 General practitioners who responded to the survey; 21 outpatients in the ear, nose, and throat department with occlusive wax. RESULTS: 274 General practitioners removed wax by syringing, but only 53 (19%) always performed the procedure themselves; the remainder routinely delegated the task to practice nurses, some of whom had received no instruction. Ears were rarely examined again after the procedure. Complications had been experienced by 105 practitioners (38%) and included perforation, canal lacerations, and failure of wax removal. The removal of occlusive wax improved hearing by a mean of 5 dB over the frequencies analysed. CONCLUSIONS: About 44,000 ears are syringed each year in the area and complications requiring specialist referral are estimated to occur in 1/1000 ears syringed. The incidence of complications could be reduced by a greater awareness of the potential hazards, increased instruction of personnel, and more careful selection of patients.

Cerumen↗
PubMed1990

The overconfidence effect in social prediction.

In five studies with overlapping designs and intents, subjects predicted a specific peer's responses to a variety of stimulus situations, each of which offered a pair of mutually exclusive and exhaustive response alternatives. Each prediction was accompanied by a subjective probability estimate reflecting the subjects' confidence in its accuracy--a measure validated in Study 5 by having subjects choose whether to "gamble" on the accuracy of their prediction or on the outcome of a simple aleatory event. Our primary finding was that in social prediction, as in other judgmental domains, subjects consistently proved to be highly overconfident. That is, regardless of the type of prediction item (e.g., responses to hypothetical dilemmas, responses to contrived laboratory situations, or self-reports of everyday behaviors) and regardless of the type of information available about the person whose responses they were predicting (e.g., predictions about roommates or predictions based on prior interviews), the levels of accuracy subjects achieved fell considerably below the levels required to justify their confidence levels. Further analysis revealed two specific sources of overconfidence. First, subjects generally were overconfident to the extent they were highly confident. Second, subjects were most likely to be overconfident when they knowingly or unknowingly made predictions that ran counter to the relevant response base rates and, as a consequence, achieved low accuracy rates that their confidence estimates failed to anticipate. Theoretical and normative implications are discussed and proposals for subsequent research offered.

Adult↗
PubMed1990

Overconfident prediction of future actions and outcomes by self and others.

In a follow-up study to Dunning, Griffin, Milojkovic, and L. Ross (1990), which had investigated the phenomenon of overconfidence in social prediction, two samples of first-year undergraduates were invited to make predictions about their own future responses (and, in the case of Sample 2, also those of their roommates) over the months ahead. These predictions were accompanied by confidence estimates and were evaluated in the light of actual responses reported later by the subjects in question. The primary finding was that self-predictions, like social predictions, proved to be consistently overconfident. As in Dunning et al., moreover, overconfidence could be traced to two sources. First, expressions of particularly high confidence rarely proved to be warranted; as confidence increased, the gap between accuracy and confidence widened. Second, predictions that went against relevant base rates yielded very low accuracy in the face of relatively unattenuated confidence levels. The implications of these results are discussed, and one potentially important underlying mechanism--the failure to make adequate inferential allowance for the uncertainties of situational construal--is proposed for further research.

Choice Behavior↗
PubMed1990

The role of construal processes in overconfident predictions about the self and others.

Overconfident behavioral predictions and trait inferences may occur because people make inadequate allowance for the uncertainties of situational construal. In Studies 1-3, Ss estimated how much time or money they would spend in various hypothetical, incompletely specified situations. Ss then offered associated "confidence limits" under different "construal conditions". In Study 4, Ss made trait inferences about someone they believed had responded "deviantly"--again with situational details unspecified and construal conditions manipulated. In all 4 studies, Ss who made predictions or trait inferences without being able to assume the accuracy of their situational construals offered confidence limits no broader than those of Ss who made their responses contingent on such accuracy. Only in conditions where Ss were obliged to offer alternative construals did they appropriately broaden their confidence limits or weaken their trait inferences.

Adult↗
PubMed1990

Land use associations and changes in population indices of urban raccoons during a rabies epizootic.

Land use associations and changes in population indices were assessed for an urban population of raccoons (Procyon lotor) in Baltimore, Maryland (USA), from January 1984 to December 1987. Records were examined for 1,458 raccoons trapped alive and removed dead from city streets during, and after, the peak of a rabies epizootic. The distribution of raccoons was associated with single-unit residential areas primarily along the northern and western perimeter of the city. Beginning in March 1985 an ending in May 1987, an epizootic of raccoon rabies spread through Baltimore, ultimately resulting in the identification of 95 rabid raccoons. Within the study interval, annual numbers of trapped raccoons remained stable from 1984 to 1986, before showing a marked decline in 1987. The number of raccoons removed as vehicle mortalities (road-kills) varied little from 1984-1985 but declined in the last 2 yr of study. Numbers of other road-killed species did not decrease concurrently, suggesting a specific decrease in the urban raccoon population. The rabies epizootic, in conjunction with the increased city and private control, appears to have contributed to a decline in the number of raccoons in Baltimore.

Animals↗
PubMed1989

Spinal epidural lipomatosis: a serious complication of iatrogenic Cushing's syndrome.

Our experience and review of the literature demonstrate that spinal epidural lipomatosis is a rare but serious neurologic complication of iatrogenic Cushing's syndrome. Most patients develop slowly progressive paraparesis over months, but a subgroup exists which presents with acute, irreversible paraplegia. We consider therapeutic options.

Adolescent↗
PubMed1988

Recognition and repair of the CC-1065-(N3-adenine)-DNA adduct by the UVRABC nucleases.

The recognition and repair of the helix-stabilizing and relatively nondistortive CC-1065-(N3-adenine)-DNA adduct by UVRABC nuclease has been investigated both in vivo with phi X174 RFI DNA by a transfection assay and in vitro by a site-directed adduct in a 117 base pair fragment from M13mp1. CC-1065 is a potent antitumor antibiotic produced by Streptomyces zelensis which binds within the minor groove of DNA through N3 of adenine. In contrast to the helix-destabilizing and distortive modifications of DNA caused by ultraviolet light or N-acetoxy-2-(acetylamino)fluorene, CC-1065 increases the melting point of DNA and decreases the S1 nuclease activity. Using a viral DNA-Escherichia coli transfection system, we have found that the uvrA, uvrB, and uvrC genes, which code for the major excision repair proteins for UV- and NAAAF-induced DNA damage, are also involved in the repair of CC-1065-DNA adducts. In contrast, the uvrD gene product, which has been found to be involved in the repair of UV damage, has no effect in repairing CC-1065-DNA adducts. Purified UVRA, UVRB, and UVRC proteins must work in concert to incise the drug-modified phi X174 RFI DNA. Using a site-directed and multiple CC-1065 modified (MspI-BstNI) 117 base pair fragment from M13mp1, we have found that UVRABC nuclease incises at the eighth phosphodiester bond on the 5' side of the CC-1065-DNA adduct on the drug-modified strand.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenine↗