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S J Verhulst

Publications and source records attributed to S J Verhulst.

At least 19 recordsLinked to original sources
PubMed2004

B- and T-cell markers in opsoclonus-myoclonus syndrome: immunophenotyping of CSF lymphocytes.

BACKGROUND: Although many lines of evidence suggest an autoimmune etiology, the pathophysiology of opsoclonus-myoclonus syndrome (OMS) remains poorly understood and no immunologic abnormalities have correlated with neurologic severity. Conventional immunotherapies often do not prevent relapse or permanent sequelae. OBJECTIVE: To test the cellular immune hypothesis of OMS in a cross-sectional study and determine if CSF lymphocyte subset analysis provides biomarkers of disease activity. METHODS: The expression of lymphocyte surface antigens was investigated in CSF and blood of 36 children with OMS and 18 control subjects, using a comprehensive panel of monoclonal antibodies to adhesion and activation proteins in combination with anti-CD3 and anti-CD45 antibodies in four-color fluorescence-activated cell sorting. RESULTS: Although most children with OMS had normal CSF cell counts, they exhibited expansion of CD19+ B-cell (up to 29%) and gammadelta T-cell (up to 26%) subsets and a lower percentage of CD4+ T-cells and CD4/CD8 ratio, which persisted even years after disease onset and conventional treatments. The percentage of activated CSF T-cells was also higher. Abnormalities correlated with neurologic severity, as scored blinded from videotapes using a 12-item motor scale, and disease duration. No significant differences were found between tumor and no-tumor groups. In children with neuroblastoma, tumor resection or cancer chemotherapy did not alter immunologic abnormalities. CONCLUSIONS: CSF B- and T-cell recruitment is linked to neurologic signs in pediatric OMS, which may relate to relapses and disease progression.

Antigens, CD19↗
PubMed2003

Strain differences in sleep patterns of healthy and influenza-infected inbred mice.

Influenza-infected C57BL/6J and BALB/cByJ mice respectively develop increased slow-wave sleep (SWS) during the dark phase and reduced SWS during the light phase of the 24 hour circadian cycle. To determine whether similar or alternative variations in SWS develop after influenza infection in other inbred strains of mice, we characterized the sleep patterns of additional strains both before and after influenza infection. Three strains (A/J, BALB/cByJ, and C3H/HeJ) showed light-phase SWS suppression, two strains (C57BL/6J and DBA/2J) showed dark-phase SWS enhancement, and one strain (A/J) showed dark-phase SWS suppression. Three strains (AKR/J, C57BR/cdJ, and FVB/NJ) did not show significant changes in SWS time on day two post-inoculation. Core temperatures were correlated to change in SWS time after infection, but were not correlated to SWS during the baseline period. These data support and expand the existing literature that indicates genetic modulation of sleep both in healthy mice and in mice undergoing viral infection.

Animals↗
PubMed2001

The effect of heel elevation on strain within the plantar aponeurosis: in vitro study.

Mild, temporary reduction of symptoms from plantar fasciitis have been reported with the use of high heeled shoes (i.e. cowboy boots, ladies pumps). However, little is known on how heel elevation may contribute to a decrease in the pain and inflammation. The aim of this study was to quantify strain in the plantar aponeurosis in cadaveric feet with the use of various heel elevation configurations. An in vitro method that simulated "static" stance was used to determine the loading characteristics of the plantar aponeurosis (n = 12). Heel elevation was evaluated with blocks placed beneath the heel and with a contoured platform that simulated the arch profile of a shoe at three different heel heights (2.0, 4.0, 6.0 cm) with a level plane serving as the control. Strain in the plantar aponeurosis decreased with elevations of the heel that simulated the arch profile of a shoe at load levels (337, 450 N) (P < 0.05). Elevations of the heel with blocks did not significantly affect strain in the plantar aponeurosis (P < 0.05). Contrasting results of some specimen limbs compared with the overall means suggests that the influence of heel elevation on loading of the plantar aponeurosis may be dependent on individual variation and foot structure differences. Therefore, clinicians should be cautious in recommending heel elevation as a treatment for plantar fasciitis since some subjects may not achieve the desired decrease in plantar aponeurosis strain.

Adult↗
PubMed2000

Predictive utility of the Bayley Infant Neurodevelopmental Screener (BINS) risk status classifications: clinical interpretation and application.

Predictive validity and clinical implications of the increasingly popular Bayley Infant Neurodevelopmental Screener (BINS) risk status classifications have not been previously reported. In this longitudinal follow-up study, the BINS was administered to high-risk infants at 6, 12, and 24 months of age, and the McCarthy Scales at 3 years of age. Ninety-two children were evaluated at 6 and 36 months, 105 at 12 and 36 months, and 118 at 24 and 36 months; 190, 125, and 140 infants were included in the comparisons at 6 to 12, 6 to 24, and 12 to 24 months. BINS risk status was classified as low, moderate, or high; or as a binary variable, LOWRISK/HIGHRISK. The three BINS items groups were moderately correlated. Consistency was most variable in the moderate-risk group. BINS risk was predictive of 36-month function in 18 out of 18 comparisons. Odds ratios, ranging from 2.76 to 54.70, were significant in 15 out of 18 logistic models. An early high-risk classification was associated with increased probability of later developmental morbidity. The BINS offers an alternative to detailed assessment in high-volume clinical applications and has good concurrent and predictive validity.

Child Development↗
PubMed1999

Stabilization of eyelid height after aponeurotic ptosis repair.

OBJECTIVE: To develop guidelines for revision of ptosis surgery in the early postoperative period by establishing what percentage of eyelids after anterior levator advancement have reached their final height by the first postoperative week. DESIGN: Prospective noncomparative case series. PARTICIPANTS: An analysis was performed on 164 eyelids in 97 patients with involutional aponeurotic ptosis. INTERVENTION: Anterior levator advancement was performed on each of these 164 eyelids. Exclusion criterion consisted of a history or evidence of neurologic or muscular disease, preceding trauma, an anophthalmic socket, or prior eyelid surgery. MAIN OUTCOME MEASURES: The marginal reflex distance, eyelid excursion, and degree of swelling were recorded perioperatively; additionally, photographs were obtained before surgery and at 1 and 6 weeks after surgery. RESULTS: At 1 week after surgery, only 40% of eyelids had reached their final height; 52% continued to rise a mean of 1.1 mm. The percentage of eyelids continuing to rise after the first postoperative week varied with the amount of swelling present at 1 week, although a direct correlation did not exist (Pearson correlation, 0.22; P < 0.26). Although this increase ranged from 0.5 to 3.0 mm for 71% of eyelids, the subsequent increase was 1 mm or less. Maximal eyelid height was achieved almost universally by 6 weeks, after which 18% of eyelids subsequently dropped a mean of 0.8 mm. CONCLUSIONS: Based on this study, the authors suggest revision at 1 week after anterior levator advancements in which minimal-to-moderate eyelid swelling exists for contour abnormalities, if the eyelid height is 0.5 mm or more above or more than 1.0 mm below the target height, or if asymmetry between the eyelids is 1.0 mm or more. The authors do not advise early revision for patients with excessive swelling still present 1 week after surgery.

Adult↗
PubMed1996

Patellar tilt in total knee arthroplasty.

Eighty-nine consecutive primary total knee arthroplasties performed for osteoarthrosis were evaluated to determine the effect of patellar thickness, alignment, joint line, patellar height, type of patellar prosthesis, and length of follow-up on patellar tilt. Preoperatively, 62% of the patellae were tilted neutrally and 38% tilted laterally on standard 45 degrees Merchant-view radiographs. At 3-week follow-up, 52% were neutral, 32% tilted laterally and 16% tilted medially. At the most recent follow-up (mean 36 months), 41% were neutral, 46% tilted laterally and 13% tilted medially. Five (5.6%) required reoperation for patellar complications. Change in joint line, in alignment, and in patellar height had no effect on postoperative patellar tilt. Patients who required a lateral release had postoperative patellar tilt measurements that were not statistically different from those who did not require a lateral release. Metal-back domed patellae were more likely to tilt laterally than all-polyethylene domed patellae; however, the metal-back patellae had a longer mean follow-up (41 months) compared with the all-polyethylene patellae (27 months). The positive correlation between preoperative patellar thickness and postoperative patellar tilt was statistically significant. The negative correlation between change in patellar thickness and postoperative patellar tilt also was statistically significant. Finally, postoperative medically tilted patellae moved toward neutral with time and laterally tilted patellae not only remained laterally tilted but also the tilt increased with time.

Aged↗
PubMed1995

Serum prolactin levels and neonatal seizures.

To assess the effects of neonatal seizures on the hypothalamus and to test clinical use of prolactin as a neonatal seizure marker, we studied postictal and recovery baseline serum prolactin levels in 19 neonates whose seizures were classified according to their clinical and EEG features. Postictal prolactin levels were obtained 30 min after the seizure, and recovery levels were ascertained 2-4 days later. The ratio of postictal prolactin level to recovery baseline level (prolactin ratio) was used as an indicator of postictal prolactin increase. The specificity and sensitivity of a prolactin ratio of > 2 was compared with the current standard of diagnosis (seizure discharges recorded by ictal EEG). Infants with electroclinical seizures had significantly higher prolactin ratios than control infants or infants with seizures without EEG correlation. Marked prolactin increases were noted only in infants with focal tonic seizures and temporal electrode involvement. A prolactin ratio of > 2 had a specificity of 100% and a sensitivity of 40%. We conclude that neonatal seizures have variable effects on the hypothalamus and that the low sensitivity and the need to await recovery levels limit the clinical value of prolactin ratio as a neonatal seizure marker.

Biomarkers↗
PubMed1994

Evaluation of an educational program for asthmatic children ages 4-8 and their parents.

BACKGROUND: Evaluation of a number of asthma education programs for children 8-13 has shown improved self-management behaviors and decreased use of healthcare services. However, nearly 80% of children with asthma develop symptoms by age 5. MATERIALS & METHODS: We evaluated a program (Huff and Puff: The Children's Asthma Program) that addresses the developmental learning needs of children ages 4-8. This multicenter study employed a pre- and post-test design to evaluate the impact of the Program on cognitive, behavioral, and affective learning and medical care utilization. We report here data on 128 of the 130 children who completed the program and on the 125 households on which we have nonduplicated data. RESULTS: Statistically significant changes were observed in all categories of learning in those who completed the Program. Medical care utilization (including hospitalizations, days of hospitalization, emergency room visits and sick visits to the physician for "out-of-control" asthma) demonstrated statistically significant decreases. CONCLUSION: The Program was shown to be an effective educational intervention for children 4-8 years of age and their parents in this cohort (nonrandomized, noncontrolled study of volunteers). Future research should also explore ways to utilize and adapt the program for specific populations such as inner-city children and parents and non-English speaking groups.

Asthma↗
PubMed1993

Attention deficits in children and adolescents with hearing loss. A survey.

OBJECTIVES: To determine the prevalence of reported attention deficits in a sample of children who are deaf or hard of hearing and to examine associated variables. DESIGN: Cross-sectional survey. SETTING: Residential school for the deaf. PARTICIPANTS: All students attending the school (n = 238; median age, 16.0 years; range, 4 to 21 years). Subjects were subgrouped by cause of deafness for further analyses. INTERVENTION: None. MEASUREMENTS/MAIN RESULTS: School personnel completed questionnaires that are commonly used in the assessment of attention problems. Teachers completed the Attention Deficit Disorder With Hyperactivity (ADD-H) Comprehensive Teacher Rating Scale (ACTeRS) and an abbreviated version of the Attention-Activity section of the ANSER (Aggregate Neurobehavioral Student Health and Education Review) System Questionnaires. Dormitory supervisors rated students on the Conners' Parent Rating Scale and the ANSER System Questionnaires. The mean factor scores for the total sample of deaf and hard-of-hearing students on the Attention and Hyperactivity scales of the ACTeRS and Conners' questionnaires did not differ from the normative data. The 64 students with hereditary deafness received significantly better ratings than the 75 with an acquired cause of deafness such as bacterial meningitis or congenital rubella. Raw scores on the ACTeRS were converted to percentile equivalents based on the normative sample. On the Attention Scale, 38.7% of those with acquired deafness were rated below the 20th percentile (indicative of problems); only 14.1% of the students with hereditary deafness were in this range (P = .002). CONCLUSIONS: Ratings of attention for students with hearing loss, attending a residential school, did not differ from the normative data. However, the subgroup of children with acquired sensorineural deafness appear to be at increased risk for attention problems.

Adolescent↗
PubMed1993

Clinical performance-based test sensitivity and specificity in predicting first-year residency performance.

To assess the use of a standardized-patient-based postclerkship examination (PCX) to predict students' performances in their first year of residency, the authors used data from 202 students of the classes of 1987, 1988, and 1990 at the Southern Illinois University School of Medicine. The PCX was found to be more sensitive than specific in that it identified more correctly those students who received high ratings in their first year of residency than those who received low ratings. Consequently, while the rate of false negatives was low across the three classes, the rate of false positives was relatively high. Analyses of the supervisors' written comments on residents' performances indicated that more than half of the false positives and false negatives resulted mostly from problems found with the supervisors' ratings, rather than from the inaccuracy of the PCX in predicting students' residency performances. The supervisors' ratings did not always match their written comments and did not always represent pure assessments of the residents' cognitive performances. Finally, because of the large number of missing residency performance ratings among the graduates who had performed unsatisfactorily on the PCX, it is expected that the sensitivity of the PCX may be overestimated and its specificity underestimated. Overall, the results suggest that the standardized-patient-based PCX is a useful indicator of students' readiness for and performance in residency.

Clinical Competence↗
PubMed1993

Examination of nonresponse bias in a major residency follow-up study.

Nonresponse bias is a potential problem for follow-up studies that track medical school graduates into their residencies. There are two main types of nonresponse: when residents' supervisors do not complete the study evaluation forms and when medical students refuse permission to allow follow-up evaluations during their residencies. The present study discloses the biases that each of these types of nonresponse produced on a set of standard measures of 508 residents from eight 1980s medical school classes at Southern Illinois University. The standard measures (e.g., MCAT scores, grade-point averages, NBME scores) were collected when the residents were medical students. The findings clearly indicate that the scores of the medical students who granted permission for follow-up evaluations had significantly larger means than did the scores on the same measures of those students not granting permission, clearly a source of nonresponse bias. On the other hand, no significant difference in scores (thus negligible bias) was found in cases where supervisors did not complete forms. The authors offer suggestions for medical school policies based on these findings.

Achievement↗
PubMed1993

Causes of urinary incontinence after acute hemispheric stroke.

BACKGROUND AND PURPOSE: We prospectively studied bladder function in stroke patients to determine the mechanisms responsible for poststroke urinary incontinence. METHODS: Fifty-one patients with recent unilateral ischemic hemispheric stroke admitted to a neurorehabilitation unit were enrolled. The presence of urinary incontinence was correlated with infarct location, neurological deficits, and functional status. Urodynamic studies were performed on all incontinent patients. RESULTS: Nineteen patients (37%) were incontinent. Incontinence was associated with large infarcts, aphasia, cognitive impairment, and functional disability (p < 0.05) but not with age, sex, side of stroke, or time from stroke to entry in the study. Urodynamic studies, performed on all 19 incontinent patients, revealed bladder hyperreflexia in 37%, normal studies in 37%, bladder hyporeflexia in 21%, and detrusor-sphincter dyssynergia in 5%. All of the patients with normal urodynamic studies were aphasic, demented, or severely functionally impaired. All of the patients with hyporeflexic bladders had underlying diabetes or were taking anticholinergic medications. Forty-six percent of incontinent patients treated with scheduled voiding alone were continent at discharge compared with 17% of patients treated pharmacologically. CONCLUSIONS: There are three major mechanisms responsible for poststroke urinary incontinence: 1) disruption of the neuromicturition pathways, resulting in bladder hyperreflexia and urgency incontinence; 2) incontinence due to stroke-related cognitive and language deficits, with normal bladder function; and 3) concurrent neuropathy or medication use, resulting in bladder hyporeflexia and overflow incontinence. Urodynamic studies are of benefit in establishing the cause of incontinence. Scheduled voiding is a useful first-line treatment in many cases of incontinence.

Aged↗
PubMed1993

Predictors of frequent middle school health room use.

Disproportionately high use of school health room (HR) services by small groups of users has been reported. This study investigated predictors of frequent HR use in two suburban middle schools involving 1089 students who made at least one HR visit during a single academic year. Subsets of high and low users were compared using logistic regression. Predictor variables included gender, grade, academic ability, and existence of a chronic health condition. Although demographic characteristics of the study schools varied significantly, a pattern of increasing HR use associated with progressive lowering of academic ability was demonstrated in both schools. Existence of a chronic health condition was associated with increased HR use, even when controlling for routine medication visits. Gender and grade were not predictive. These findings suggest that HR use reflects more than medical concerns. Patterns of HR use by students with chronic health conditions deserve additional study to determine whether current strategies to meet their needs are adequate.

Adolescent↗
PubMed1992

Six years of comprehensive, clinical, performance-based assessment using standardized patients at the Southern Illinois University School of Medicine.

By the end of 1990-91, the Southern Illinois University School of Medicine had had six years of experience with comprehensive, performance-based examinations of senior medical students' levels of clinical competence; this report assesses the psychometric aspects of the six examinations given during that period. The examinations were aimed at determining the students' readiness for postgraduate training. Compared with other clinical performance-based assessments that use standardized patients (SPs), these examinations had two important and unique features: (1) the examinations assessed a comprehensive range of clinical skills and reasoning; and (2) they approximated the challenges of real clinical practice wherein a practitioner's skills need to be orchestrated and prioritized in order to meet the challenges of the case encountered. Each year, the performance-based assessment given was an intensive clinical examination requiring each student to work up 13 to 18 SP problems over a three-day period. To administer an examination to an entire class of students took three weeks. Because all students after the first year of administration (1986) were required to pass these examinations, the fairness of test design and scoring and the setting of performance standards for the examinations became important issues for the faculty. The results, accumulated over six years and based on a total of 6,804 student-patient encounters involving 405 students, indicate that this kind of clinical performance-based examination can discriminate a wide range of students' clinical performances. The results provide evidence for the examinations' test security, content validity, construct validity, and reliability.

Clinical Clerkship↗
PubMed1992

Standardized (simulated) patients' accuracy in recording clinical performance check-list items.

In large-scale performance-based assessment of medical professionals' clinical competence, simulated patients (standardized patients-SPs) are used not only to simulate case problems but also to record on check-list the examinees' clinical performance during their encounter with the SPs. The purposes of this study were to determine the SPs' overall accuracy in recording check-list items, and whether their accuracy was affected by the various characteristics of the check-list, and by the different times during a day and the different days within the examination when the recordings were obtained. Results showed that the SPs' accuracy in recording check-list items was good to very good and was affected by the length of the check-list, as well as by the type and the clarity of the check-list item. It was further found that the SPs' accuracy was consistent and did not vary over the course of a one-day or a 15-day examination.

Clinical Competence↗