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S J Sullivan

Publications and source records attributed to S J Sullivan.

At least 19 recordsLinked to original sources
PubMed1998

Genomic instability and catalase gene amplification induced by chronic exposure to oxidative stress.

Chronic exposure (>200 days) of HA1 fibroblasts to increasing concentrations of H2O2 or O2 results in the development of a stable oxidative stress-resistant phenotype characterized by increased cellular antioxidant levels, particularly catalase (D. R. Spitz et al, Arch. Biochem. Biophys., 279: 249-260, 1990; D. R. Spitz et al., Arch. Biochem. Biophys., 292: 221-227, 1992; S. J. Sullivan et al., Am. J. Physiol. (Lung Cell. Mol. Physiol.), 262: L748-L756, 1992). Acutely stressed cells failed to develop a stably resistant phenotype or increased catalase activity, suggesting that chronic exposure is required for the development of this phenotype. This study investigates the mechanism underlying increased catalase activity in the H2O2- and O2-resistant cell lines. In H2O2- and O2-resistant cells, catalase activity was found to be 20-30-fold higher than that in the parental HA1 cells and correlated with increased immunoreactive catalase protein and steady-state catalase mRNA levels. Resistant cell lines also demonstrated a 4-6-fold increase in catalase gene copy number by Southern blot analysis, which is indicative of gene amplification. Chromosome banding and in situ hybridization studies identified a single amplified catalase gene site located on a rearranged chromosome with banding similarities to Z-4 in the hamster fibroblast karyotype. Simultaneous in situ hybridization with a Z-4-specific adenine phosphoribosyltransferase (APRT) gene revealed that the amplified catalase genes were located proximate to APRT on the same chromosome in all resistant cells. In contrast, HA1 cells contained only single copies of the catalase gene that were not located on APRT-containing chromosomes, indicating that amplification is associated with a chromosomal rearrangement possibly involving Z-4. The fact that chronic exposure of HA1 cells to either HO2 or 95% O2 resulted in gene amplification suggests that gene amplification represents a generalized response to oxidative stress, contributing to the development of resistant phenotypes. These results support the hypothesis that chronic exposure to endogenous metabolic or exogenous environmental oxidative stress represents an important factor contributing to gene amplification and genomic instability.

Adenine Phosphoribosyltransferase↗
PubMed1998

Motor performance following a mild traumatic brain injury in children: an exploratory study.

Mild Traumatic Brain Injury (TBI) is a common occurrence in the paediatric population and, as the concept of motor performance has not been assessed specifically in this population, the purpose of this study was to determine if motor performance deficits are present and can be objectively identified in a sample of children having sustained a mild TBI (Glasgow Coma Scale score 13-15). Twenty-eight children aged between 5 and 15 years were recruited immediately post-trauma. Subjects were considered normal on standard neurological exam at the time of discharge. They were assessed 13-18 days post-trauma using the Bruininks-Oseretsky Test of Motor Proficiency, a norm referenced clinical standardized assessment tool. Compared to published norms, motor performance was significantly lower in domains of balance, response speed and running speed an agility (t-test p < 0.01), and significantly higher in domains of upper extremity coordination and visual motor control (t-test p < 0.01). Although excellent performance can be observed in domains requiring upper limb coordination, motor planning and execution of motor tasks, deficits in balance and response speed can be identified in a significant number of children even after mild TBI. More specific and sensitive evaluations are necessary to identify the exact nature of the problems and evaluate their functional impact on daily activities.

Adolescent↗
PubMed1998

Inhibitory influence of soleus massage onto the medial gastrocnemius H-reflex.

It has previously been reported that the soleus Hoffmann (H-)reflex is diminished in amplitude during a massage of the ipsilateral triceps surae. A question arises as to the origin of this decrease. The purpose of this study was to determine whether massage does indeed diminish motoneuronal excitability or whether the decrease is an artefact associated with the experimental procedures, i.e. saturation of the transmission capacity of the afferent pathway. H-reflexes and the corresponding muscle (m-)responses were recorded from the medial gastrocnemius (MG) muscle during a 3-minute massage of the ipsilateral soleus muscle in 12 neurologically healthy adults during 4 control conditions (C1, C2, C4, C5) and 1 experimental (C3-massage) condition. Peak-to-peak mean amplitudes of the MG H-reflex obtained during massage were significantly reduced in comparison to all control values recorded while the subjects were at rest. These results suggest that massage does indeed diminish motoneuronal excitability, since these effects were not restricted to the homonymous motoneurone pool, but could also be demonstrated for a close synergistic muscle, uninvolved in the massage.

Adult↗
PubMed1997

Reliability for a walk/run test to estimate aerobic capacity in a brain-injured population.

The purpose of this study was to establish the test-retest reliability of a modified 20 m shuttle walk/run test of aerobic capacity for adults with traumatic brain injuries (TBI). A convenience sample of 18 TBI patients (16 males, two females) between 19 and 58 years of age, was tested using an externally paced, progressive, maximal shuttle walk/run, on two separate occasions, within a 1-week period. The test involving walking or running a 20 m shuttle course while maintaining the pace determined by signals from a prerecorded audiotape. The initial slow walking pace (2.4 km/h) was increased gradually, each minute, until the patient could not continue. Statistical analyses revealed excellent reliability for the number of levels completed (ICC = 0.976), total walk/run test time (S) (ICC = 0.983) and maximal heart rate attained during the final level (bpm) (ICC = 0.964). Although small but significant increases were noted for the number of levels completed during the second test, the modified 20 m shuttle walk/run seems to be a reliable field test which may be useful for assessing the aerobic capacity of brain-injured adults.

Adult↗
PubMed1996

Uncoupling of M-phase kinase activation from the completion of S-phase by heat shock.

Chronic exposure of asynchronous HeLa cell cultures to 41.5 degrees C leads to an accumulation of cells in the S-phase, spontaneous premature chromosome condensation, and loss of clonogenicity (M.A. Mackey, S. L. Anolik, and J. L. Roti Roti. Cancer Res., 52: 1101-1106, 1992). In this report, we show that increases in histone H1 kinase activity during 41.5 degrees C exposure occur coincidentally with the appearance of premature chromosome condensation. Furthermore, this kinase activity is shown to be associated with M-phase kinase complexes containing cyclin B1. These increases in the activity of M-phase kinase were found to occur concomitantly with an elevation in cyclin B1 mRNA and an accumulation of cyclin B1 protein. Because cyclin B1 transcription begins in the S-phase, it is probable that the heat-induced delay in the S-phase allows the accumulation of abnormally high cyclin B1 levels. Elevated cyclin B1 levels could then account for the observed abrogation of the cell cycle checkpoint, which usually assures that mitosis does not proceed until DNA replication is complete. This involvement of M-phase kinase in heat-induced cytotoxicity demonstrates the importance of the coordinate regulation of the processes of DNA replication and entry into mitosis.

Cell Cycle↗
PubMed1996

Motor fitness in children and adolescents with traumatic brain injury.

OBJECTIVE: This study examined the test-retest reliability of selected motor fitness test items among children with severe traumatic brain injury. DESIGN: A cohort study consisting of two testing session, one week apart. SETTING: All subjects were recruited from among the former clients of a pediatric rehabilitation center. SUBJECTS: A convenience sample of 19 subjects, 13 boys and 6 girls aged 8 to 17 years, volunteered to participate. All participants had a diagnosis of a severe traumatic brain injury (X +/- SD = 5.88 +/- 1.71 on the Glascow Coma Scale), had completed a program of physical rehabilitation, and were evaluated at 4.16 +/- 2.61 years after their injury. MAIN OUTCOME MEASURES: Performance on twelve motor fitness test items (including flexibility, agility, muscular strength, cardiorespiratory endurance, power, muscular endurance, and coordination) was measured at each of two structured evaluation sessions. RESULTS: No differences (t tests, p < or = .05) were found between the performances on the two testing sessions for any of the variables. The test-retest reliability was established via the intraclass correlation (ICC) and ranged from .84 to .98, indicating "almost perfect" agreement. CONCLUSION: The data indicate that these motor fitness testing protocols are reliable and applicable to traumatic brain injured children in a clinical setting and can thus be used by therapists to plan future interventions to improve the fitness of this clientele.

Adolescent↗
PubMed1996

Motor profile of patients in minimally responsive and persistent vegetative states.

The purpose of this descriptive clinical study is to document the motor characteristics of patients in minimally responsive and persistent vegetative states. Twelve subjects, presenting a prolonged altered state of consciousness (x = 7.82 years, range 2-27), aged 27-78 years (x = 50, SD = 15.26) were evaluated, using standardized protocols, on the following variables: passive range of motion, observed movements, reflexes, tonus, postural status and reactions. The subjects' level of awareness and responsivity were measured with the Coma/Near Coma (CNC) scale at each of the three data collection sessions. While group CNC scores were stable over the three sessions, fluctuations in the level of awareness of individual subjects was recorded, confirming the heterogeneity of this clientele. Abnormal primitive reflexes were present in all subjects, with the flexor withdrawal (75%), the tonic labyrinthine (36%) and the body-on-body righting reaction (25%) being the most frequently observed. All subjects presented altered tonus, considerable posturing and varied degrees of reduced range of joint motion. A range of abnormal (e.g. chewing, clonus) and normal patterned (e.g. bridging, scratching) movement behaviours was recorded, but these did not translate into functional use, such as rolling. Collectively, the findings stress the complexity of the motor profile of patients in minimally responsive and vegetative states, and suggest the need for physiotherapists to become more actively involved in the evaluation and treatment of this clientele.

Adult↗
PubMed1996

Longitudinal profile of early motor recovery following severe traumatic brain injury.

A prospective longitudinal design was employed to describe early (first 6 weeks post-injury) motor function recovery in 16 individuals with severe traumatic brain injury (TBI). Reliable, standardized testing and scoring protocols were used by a physical therapist to evaluate subjects on several different aspects of motor function, including primitive reflexes, equilibrium/protective reactions, and a wide range of motor skills. The findings revealed that subjects demonstrated significant changes (chi 2, p < or = 0.05) between 1 and 6 weeks for the following variables: equilibrium reactions in sitting, rolling prone to side-lying, sitting (supported and unsupported), kneeling, standing (assisted and independently), walking (assisted and independently), stair climbing with the use of the handrail and walking 25 m on even ground. A significant change in ability to sit supported between 1 and 3 weeks post-injury was also observed. In addition, recovery was found to be a heterogeneous process, in that different patterns of recovery were evident for the 26 variables and among individual subjects. The clinical implications for physical therapists involved in the rehabilitation of adults with a severe TBI are discussed.

Adolescent↗
PubMed1996

Screening of health risk factors prior to exercise or a fitness evaluation of adults with traumatic brain injury: a consensus by rehabilitation professionals.

A modified Delphi technique was used to obtain group consensus among 31 rehabilitation professionals (RPs) from nine rehabilitation centres throughout the province of Québec (Canada) to ascertain their expert opinion on the health risk factors (HRF) to be verified prior to beginning an exercise programme or evaluation for patients with traumatic brain injury (TBI). From the initial survey 87 items were generated, which were later regrouped into 27 HRFs. The relative importance of each HRF in regard to being screened before exercise in a population with TBI was then assessed by each RP using a five-point ordinal scale (1 = not important to 5 = extremely important). HRFs that were considered extremely important by at least 50% of HPs include: angina pectoris, aortic stenosis, exertional syncope, musculoskeletal sequelae which are exacerbated by exercise, outward aggressivity, pulmonary embolism, uncontrolled epilepsy (seizures), and ventricular arrhythmias. Professionals involved in exercising patients with TBI may find these factors useful to the efficient conduct of their rehabilitation programme.

Adult↗
PubMed1996

Reliability of early motor function testing in persons following severe traumatic brain injury.

The purpose of this study was to determine the intra- and inter-rater reliability of selected variables measuring motor function in adults following severe traumatic brain injury (TBI). Twelve adults with a severe TBI participated in the study and were assessed (independently) by two physical therapists with extensive clinical experience. Standardized testing protocols and two- or three-point ordinal rating scales were used to evaluate the following categories of variables: primitive reflexes, equilibrium/protective reactions and several motor skills. Intra-rater reliability was generally high for all variables, with kappa values exceeding 0.65 except for the scoring of equilibrium reactions in sitting and standing. Overall, inter-rater reliability was slightly lower, with kappa values ranging from 0.39 to 1.0, indicating 'fair' to 'almost perfect' agreement. The highest level of agreement was consistently reported for the scoring of motor skills. These results suggest that physical therapists trained in the use of standardized testing and scoring procedures can reliably assess primitive reflexes, equilibrium and protective reactions and a range of motor skills in TBI adults during the acute stage of recovery. Moreover, the results provide important information which will assist in the interpretation of data collected as part of a concurrently conducted longitudinal study of early motor recovery.

Adolescent↗
PubMed1995

Pelvic-floor rehabilitation, Part 1: Comparison of two surface electrode placements during stimulation of the pelvic-floor musculature in women who are continent using bipolar interferential currents.

BACKGROUND AND PURPOSE: Electrical stimulation of the pelvic floor is used as an adjunct in the conservative treatment of urinary incontinence. No consensus exists, however, regarding electrode placements for optimal stimulation of the pelvic-floor musculature. The purpose of this study was to compare two different bipolar electrode placements, one suggested by Laycock and Green (L2) the other by Dumoulin (D2), during electrical stimulation with interferential currents of the pelvic-floor musculature in continent women, using a two-group crossover design. SUBJECTS: Ten continent female volunteers, ranging in age from 20 to 39 years (mean = 27.3, SD = 5.6), were randomly assigned to one of two study groups. METHODS: Each study group received neuromuscular electrical stimulation (NMES) of the pelvic-floor musculature using both electrode placements, the order of application being reversed for each group. Force of contraction was measured as pressure (in centimeters of water [cm H2O]) exerted on a vaginal pressure probe attached to a manometer. Data were analyzed using a two-way, mixed-model analysis of variance. RESULTS: No difference in pressure was observed between the two electrode placements. Differences in current amplitude were observed, with the D2 electrode placement requiring less current amplitude to produce a maximum recorded pressure on the manometer. Subjective assessment by the subjects revealed a preference for the D2 electrode placement (7 of 10 subjects). CONCLUSION AND DISCUSSION: The lower current amplitudes required with the D2 placement to obtain recordings comparable to those obtained with the L2 technique suggest a more comfortable stimulation of the pelvic-floor muscles. The lower current amplitudes required also suggest that greater increases in pressure might be obtained with the D2 placement by increasing the current amplitude while remaining within the comfort threshold. These results will help to define treatment guidelines for a planned clinical study investigating the effects of NMES and exercise in the treatment of urinary stress incontinence in women postpartum. [Dumoulin C, Seaborne DE, Quirion-DeGirardi C, Sullivan SJ. Pelvic-floor rehabilitation, part 1: comparison of two surface electrode placements during stimulation of the pelvic-floor musculature in women who are continent using bipolar interferential currents.

Adult↗
PubMed1995

Pelvic-floor rehabilitation, Part 2: Pelvic-floor reeducation with interferential currents and exercise in the treatment of genuine stress incontinence in postpartum women--a cohort study.

BACKGROUND AND PURPOSE: This descriptive cohort study investigated a physical therapy program of pelvic-floor neuromuscular electrostimulation (NMES) combined with exercises, with the aim of developing a simple, inexpensive, and conservative treatment for postpartum genuine stress incontinence (GSI). SUBJECTS: Eight female subjects with urodynamically established GSI persisting more than 3 months after delivery participated in the study. The subjects ranged in age from 24 to 37 years (X = 32, SD = 4.2). METHODS: This was a descriptive multiple-subject cohort study. Each subject received a total of nine treatment sessions during 3 consecutive weeks, consisting of two 15-minute sessions of NMES followed by a 15-minute pelvic-floor muscle exercise program. Patients also practiced daily pelvic-floor exercises during the 3-week treatment period. The treatment intervention was measured using three separate variables. Maximum muscle contractions (pretraining, during training, and post-training) were measured indirectly as pressure, using perineometry. Urine loss pretraining and posttraining was measured by means of a Pad test. Self-reported frequency of incontinence was recorded daily throughout the period of the study, using a diary. Data were analyzed using a one-way repeated-measures analysis of variance (ANOVA), a Wilcoxon signed-ranks test, and a Friedman two-way ANOVA by ranks. RESULTS: The results indicated that maximum pressure generated by pelvic-floor contractions was greater and both the quantity of urine loss and the frequency of incontinence were lower following the implementation of the physical therapy program. Five subjects became continent, and three others improved. A follow-up survey 1 year later confirmed the consistency of these results. CONCLUSION AND DISCUSSION: The results suggest that the proposed physical therapy program may influence postpartum GSI. Further studies are needed to validate this simple, inexpensive, and conservative physical therapy protocol. [Dumoulin C, Seaborne DE, Quirion-DeGirardi C, Sullivan SJ. Pelvic-floor rehabilitation, part 2: pelvic-floor reeducation with interferential currents and exercise in the treatment of genuine stress incontinence in postpartum women--a cohort study.

Adult↗
PubMed1995

Rapid assay for mycobacterial growth and antibiotic susceptibility using gel microdrop encapsulation.

Effective control of tuberculosis transmission in vulnerable population groups is dependent on rapid identification of the infectious agent and its drug susceptibility. However, the slow growth rate of mycobacteria has undermined the ability to quickly identify antimicrobial resistance. These studies describe a mycobacterial growth assay based on microencapsulation technology used in conjunction with flow cytometric analysis. Mycobacteria were encapsulated in agarose gel microdrops approximately 25 microns in diameter, and colony growth was monitored by using flow cytometry to evaluate the intensity of auramine staining after culture for various times at 37 degrees C. By this method, colony growth of Mycobacterium bovis and M. smegmatis could be quantified within 1 to 3 days after encapsulation. Inhibition of growth by rifampin and isoniazid was also evaluated in this time period, and the presence of an isoniazid-resistant subpopulation representing 3% of the total microorganisms could be detected. This use of encapsulation and flow cytometry has the potential to facilitate rapid and automated evaluation of inhibition of growth by antimicrobial agents and shorten the time frame for analysis of clinical specimens.

Bacteriological Techniques↗
PubMed1995

Changes in the hemiparetic limb with training. I. Torque output.

The study concerns eleven patients who had suffered from a cerebro-vascular accident (CVA) less than 6 months previously and who were hospitalized for treatment. In addition to their multidisciplinary rehabilitation treatments, the patients consented to participate in an electromyographic (EMG) biofeedback program designed to increase their shoulder activity. From blocks of five individual isometric contractions, curves of both the mean torque and of its standard deviation (SD) were generated and from each of these, a mean value was obtained. These two measures were used to analyze the effects on the biofeedback training had induced on shoulder activity. The training induced negligible changes on the contralateral (CL) side. The mean torque value for the group was 31.02 post vs 30.99 Nm pre-training. However, for the hemiplegic (HEMI) limbs, some patients showed improvement while others did not. The treatment was considered a success when the mean torque values obtained in the last 2/3 of the training or at the post-training session were > or = 1.5 the values obtained during the pre-training session. Based on this criteria, it was found that six out of eleven patients did improve their muscular activity through the training. Among these, the improvement of four was greater during the 2/3 session than that observed at the post-training session. The six successful patients were found to have a pre-training upper extremity Fugl-Meyer score < or = 13. Two patients had a similar pre-training score of 11, and met the criteria of success, but the younger patient performed better than the older one. Patients with scores of 20 and higher did not meet the 1.5 criteria. A correlation (r = 0.80) was found between post/pre ratios of Fugl-Meyer scores and those of the mean torque: the test thus seems to have a limited usefulness for assessing local changes such as the effects of the biofeedback treatment on the shoulder.

Adult↗
PubMed1994

The effect of therapeutic massage on H-reflex amplitude in persons with a spinal cord injury.

BACKGROUND AND PURPOSE: The effect of therapeutic massage on the H-reflex amplitude in persons without neurological impairment has been established. To investigate its effects in a sample of persons with a spinal cord injury (SCI), two independent but interrelated studies were undertaken. Study 1 investigated whether the recorded response (H-reflex amplitude) to massage with the subjects in the supine testing position was similar to that recorded in previous studies in which the subjects were tested in the prone position. This study was undertaken because the prone testing position was considered inappropriate for persons with SCI. In study 2, the therapeutic effect of massage (petrissage) on H-reflex amplitude in persons with SCI was examined. SUBJECTS: Seven persons without neurological impairment volunteered to participate in study 1, and 10 individuals with a traumatic SCI volunteered to participate in study 2. METHODS: The two studies shared many methodological features and involved the recording of 10 H-reflex and M-response peak-to-peak amplitudes from the triceps surae muscle during each of five sequential, 3-minute time periods. Massage treatment (MASS) was given during the third time period, and the premassage time periods (C1, C2) and postmassage time periods (C3, C4) served as control conditions. Study 2, in addition to recording the peak-to-peak amplitudes of the recorded responses, also included the recording of the H-reflex latencies. RESULTS: The results of study 1 showed that massage applied with the subjects in the supine position decreased the H-reflex amplitude during the massage. A 56% decrease in the H-reflex amplitude was recorded. Study 2 demonstrated a 27% mean group decrease in the H-reflex peak-to-peak amplitude during the massage for all subjects, with variations in individual responses ranging from an increase in the H-reflex amplitude of 20% to a decrease of 84%. An analysis of variance revealed that the H-reflex means of the five conditions were significantly different. Newman-Keuls post hoc analyses revealed that the mean of the MASS condition (2.01 mV) was significantly different from the means of C1, C2, and C4 (2.79, 2.81, 2.58 mV). The mean of C3 (2.42 mV) was not found to be statistically different from the means of the other conditions. These changes were noted against a stable M-response. CONCLUSION AND DISCUSSION: The results recorded in study 1 are comparable to those obtained with the subjects in the prone position. Based on these results, the supine position was adopted as the testing position for study 2. Study 2 further showed a decrease in H-reflex amplitude concomitant with massage in persons with SCI, but no long-term effects were noted.

Adult↗