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C A van Bennekom

Publications and source records attributed to C A van Bennekom.

17 recordsLinked to original sources
PubMed1999

Measurement of the effect of a bolus dose of intrathecal baclofen by a repetitive movement test.

We assessed the repetitive movement (RM) test for measuring the effect of a trial bolus dose of intrathecal baclofen on spasticity. The RM test measures passive range of motion (ROM) by electrogoniometry and stretch reflex activity (SRA) of the flexors and extensors of the knee and ankle by surface electromyography. The SRA has a dynamic component (dynamic stretch reflex, DSR) and a tonic component (tonic stretch reflex, TSR). Four hypotheses were formulated: (a) RM results show a negative relationship between SRA and ROM; (b) values on the RM test are correlated with clinical scores of tonus and spasticity; (c) RM results show a reduction in SRA after administration of the clinically optimal dose of baclofen; and (d) RM results show a dose-dependent effect of intrathecal baclofen on SRA. Twenty-four patients were selected because they had impairments and disabilities caused by intractable spasticity. A bolus of baclofen was administered with incremental doses (25-150 micrograms) until an optimal effect or no effect was obtained. The main outcome measures were RM test and clinical assessments of the Ashworth and spasm score. The results were (a) For the ankle a negative correlation was found between ROM and TSR of the flexor and extensors; for the knee a significant negative correlation was found only with the DSR of the biceps femoris. (b) A positive correlation was found between the Ashworth score and TSR of the extensors and between the spasm score and DSR and TSR of the gastrocnemius muscle. (c) Significant differences were found between baseline measurements and the optimal dose of baclofen for all measures. (d) A significant dose-dependent effect of intrathecal baclofen on the level of SRA was observed. The RM test is thus a useful clinical tool for objectively measuring the effect of intrathecal baclofen administration on spasticity in patients with an upper motor neuron syndrome.

Adolescent↗
PubMed1996

Responsiveness of the rehabilitation activities profile and the Barthel index.

The goal of this study was to compare the responsiveness for clinically meaningful change over time of a newly designed functional status scale, the Rehabilitation Activities Profile (RAP), with more frequently used Barthel Index (BI). Four techniques for the quantification of responsiveness were utilized: effect sizes, p-values, t-statistics and ROC curves. The patient's return home was chosen as external criterion. An inception cohort of stroke patients was followed during 26 weeks. All patients still hospitalized on the 14th day after the stroke were included. The functional assessments took place at 2, 3, 4, 8, 12, and 26 weeks after stroke. The patients were visited at the hospital, home, nursing home, or rehabilitation center. Of the 125 patients included in the study, 18 patients died during the observation period, 2 patients were lost to follow-up, and 1 patient refused to cooperate after 12 weeks. After 26 weeks, 104 patients remained for analysis. Three time periods were discerned: 2 to 12 weeks (early response), 12 to 26 weeks (late response), and 2 to 26 weeks after stroke (overall response). The effect sizes of the RAP were consistently higher on all three time periods than those of the BI. The p-value of the overall response mean change score of the RAP appeared to discriminate between patients returning home and those not returning home, whereas the BI failed on this point (p = 0.004 vs. 0.496). Using t-statistics, the RAP showed a higher efficiency in expressing change on all time periods (relative efficiency = 1.42, 1.77, and 1.43, respectively). The receiver operating characteristic surface area of the RAP score was higher than the area of the BI score (0.74 and 0.59, respectively for the early response period). In conclusion, all results seemed to indicate that the RAP is more responsive than the BI when returning home is chosen as an external criterion.

Activities of Daily Living↗
PubMed1995

The Rehabilitation Activities Profile: a validation study of its use as a disability index with stroke patients.

OBJECTIVE: This study evaluates the criterion, content, and construct validity of the Rehabilitation Activities Profile (RAP) in patients with stroke. This instrument is constructed for screening, monitoring, and prognosis purposes to assist clinical rehabilitation. It consists of 21 activities, covering the domains communication, mobility, personal care, occupation, and relationships. Disabilities and perceived problems are assessed in parallel on two four-point severity scales. The disability sum scores of the first four RAP domains were used in the analyses presented in this article. DESIGN: An inception cohort of stroke patients was studied during 26 weeks. Patients that were still hospitalized on the 14th day after stroke were included. The functional assessments took place 2, 3, 4, 8, 12, and 26 weeks after stroke. SETTING: The patients were visited at the hospital, at home, nursing home, or rehabilitation center. PATIENTS: 125 patients were included in the study. After 26 weeks, 105 patients were still alive; 18 patients had died, and 2 patients were lost to follow-up. MAIN OUTCOME MEASURES: The RAP, Barthel Index (BI) and Frenchay Activities Index (FAI). RESULTS: The domain "mobility+personal care" correlated highly with the BI score (r: 0.87 to 0.90). The domain "occupation" correlated with the FAI score before the stroke and 26 weeks after stroke (r: 0.72, 0.73, respectively). The disability sum score of the domain "mobility+personal care" allowed a prediction of the living arrangement 26 weeks after stroke (receiver operator characteristic area surface: 0.90). The same domain showed significant differences (p < 0.05) in the 8-week disability sum score for most living arrangements. Exceptions were rehabilitation center versus intermediate care in a nursing home (p = 0.23) and acute care hospital versus chronic care in a nursing home (p = 0.45). Hypotheses on subgroup differences in mean scores in the domains "communication" and "mobility+personal care" could be confirmed (the discerned subgroups were: gender, having a partner, motor deficit of upper or lower extremity, urinary incontinence, higher cortical deficits, conjugate deviation of the eye, coma, hemianopsia). CONCLUSION: The disability sum scores of the RAP can be used as discriminative, evaluative, and predictive indexes.

Aged↗
PubMed1990

New polymorphic DNA marker close to the fragile site FRAXA.

DNA from a human-hamster hybrid cell line, 908-K1B17, containing a small terminal portion of the long arm of the human X chromosome as well as the pericentric region of 19q was used as starting material for the isolation of an X-chromosome-specific DNA segment, RN1 (DXS369), which identifies a XmnI RFLP. Linkage analysis in fragile X families resulted in a maximum lod score of 15.3 at a recombination fraction of 0.05 between RN1 and fra(X). Analysis of recombinations around the fra(X) and distal to DXS105. Analysis of the marker content of hybrid cell line 908K1B17 suggests the localization of RN1 between DXS98 and fra(X). Heterozygosity of DXS369 is approximately 50%, which extends the diagnostic potential of RFLP analysis in fragile X families significantly.

Animals↗
PubMed1986

Ischaemic exercise test in myoadenylate deaminase deficiency and McArdle's disease: measurement of plasma adenosine, inosine and hypoxanthine.

Plasma adenosine, inosine and hypoxanthine concentrations were assayed in seven control subjects, five myoadenylate deaminase deficient (MADD) patients and six McArdle patients before and after ischaemic forearm exercise. The plasma adenosine increase was very low in all test groups and there were no significant differences. The MADD patients showed a significantly lower increase of plasma inosine and hypoxanthine after exercise as compared with the controls. In the McArdle patients the increase in plasma inosine and hypoxanthine after exercise did not differ significantly from the values measured in the controls. The ischaemic exercise test with measurement of plasma inosine and hypoxanthine might be of diagnostic value in MADD, but not in McArdle's disease.

AMP Deaminase↗
PubMed1984

In vivo induced malignant hyperthermia in pigs. I. Physiological and biochemical changes and the influence of dantrolene sodium.

The effects of an induced malignant hyperthermia (MH) crisis have been studied in the intact pig. Both physiological and biochemical changes in skeletal muscle were studied. MH was induced with 3% halothane plus a bolus injection of succinylcholine. In the prechallenge period a significant difference was observed in the concentration of certain muscle metabolites, comparing the MH-susceptible (MH+) with the non-susceptible (MH-) pigs. A lower level was measured for phosphocreatine (PCr), inosine monophosphate (IMP) and an increased level of lactate and creatine (Cr) in the susceptible pigs (MH+). The challenge caused a significant reduction of the level of PCr and adenosine in MH+ pigs, compared to the prechallenge period. After administration of dantrolene sodium, a significant decrease was measured in the level of lactate, compared to the prechallenge period as well as during the challenge. In contrast, in the control pigs no significant changes were observed in muscle metabolites, either after induction of MH or after the administration of dantrolene sodium. Enzyme activity determinations of muscle adenylate kinase and adenosine monophosphate (AMP)-deaminase did not show any difference in activity either before or during the MH crisis or after treatment with dantrolene sodium. The earliest physiological change during an induced MH crisis in our study was the rapid increase of the end-tidal CO2. Within 5 min after MH induction, end-tidal CO2 was doubled. It is concluded that the monitoring of the end-tidal CO2 is essential to diagnose MH at a very early stage.

Adenosine↗
PubMed1979

Heterozygote detection in glucose-6-phosphate dehydrogenase deficiency: limitation of hair follicle analysis.

Glucose-6-phosphate dehydrogenase deficiency was demonstrated in a case of favism. The X-linked enzyme defect was expressed in erythrocytes but not in hair root cells. Predictably, the mother shown to be a heterozygous carrier on the basis of intermediate erythrocyte glucose-6-phosphate dehydrogenase activity could not be identified as a carrier by means of hair root study. It seems to be necessary to test the hair roots of at least one enzyme-deficient member of the family to exclude false negative results, if hair root analysis is used for carrier detection. Because of the more or less clonal origin of hair roots, they remain a convenient biopsy material with which to study heterozygosity in X-linked inborn errors of metabolism.

Child↗
PubMed1979

Glucose-6-phosphate dehydrogenase deficiency: biochemical and histochemical studies on hair roots for carrier detection.

Kinetic properties of human hair root glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase were studied in order to optimize the assay of these enzymes in lysates from single hair roots. In contrast to previously reported methods, an excess of purified 6-phosphogluconate dehydrogenase was added to the glucose-6-phosphate dehydrogenase reaction mixtures, thus allowing a more exact quantification of glucose-6-phosphate dehydrogenase activity. Although enzyme histochemical techniques suggest a similar distribution of hair root glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase, enzyme assays on hair root segments after microdissection nevertheless indicate differences in the distribution of these enzymes. Upon storage a gradual drop in the activity of both hair root enzymes was found, but the rate of decrease in enzyme activity was about equal: the enzyme activity ratio was, therefore, not affected. This opens interesting possibilities for mailing hair roots for screening purposes without any special precautions.

Genetic Carrier Screening↗
PubMed1978

A simple and sensitive radiochemical assay for plasma guanase.

A simple and sensitive radiochemical micro-assay has been developed for the determination of plasma guanase activity. The method is based upon the measurement of the conversion of 14C-labeled guanine to xanthine, catalysed by the enzyme guanase (guanine aminohydrolase;EC 3.5.4.3). Using this method, the catalytic activity in the plasma of adult healthy controls was 0.040 +/- 0.09 nmol/h.mg protein (x +/- s). In children under 5 years of age higher levels of enzyme activity were demonstrated. In adult patients with liver disease plasma guanase activities were found to be 3 to 7-fold increased as compared to the normal adult mean value.

Adolescent↗
PubMedDate not supplied

Multipoint linkage analysis of DXS369 and DXS304 in fragile X families.

Diagnosis of carriers of the fragile-X mental retardation gene is hampered by the paucity of tightly linked DNA markers. Recently, 2 new DNA markers RN1 (DXS369) and U6.2 (DXS304) have become available. Both markers are tightly linked to the fragile-X locus, but their location relative to the fragile site was not known with certainty. We have tested these new markers in a multipoint linkage analysis of 26 fragile-X families typed for DXS105 as a proximal marker and DXS52 as a distal marker. Our results establish the order DXS105-DXS369-fra(X)-DXS304-DXS52, which is in agreement with physical mapping results.

DNA↗