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Biomedical subjects

S Grant

Publications and source records attributed to S Grant.

At least 109 records · Page 6Linked to original sources
PubMed1999

Initial aerobic power does not alter muscle metabolic adaptations to short-term training.

To investigate the hypothesis that training-induced increases in muscle mitochondrial potential are not obligatory to metabolic adaptations observed during submaximal exercise, regardless of peak aerobic power (VO(2 peak)) of the subjects, a short-term training study was utilized. Two groups of untrained male subjects (n = 7/group), one with a high (HI) and the other with a low (LO) VO(2 peak) (means +/- SE; 51.4 +/- 0.90 vs. 41.0 +/- 1.3 ml. kg(-1). min(-1);P < 0.05), cycled for 2 h/day at 66-69% of VO(2 peak) for 6 days. Muscle tissue was extracted from vastus lateralis at 0, 3, and 30 min of standardized cycle exercise before training (0 days) and after 3 and 6 days of training and analyzed for metabolic and enzymatic changes. During exercise after 3 days of training in the combined HI + LO group, higher (P < 0.05) concentrations (mmol/kg dry wt) of phosphocreatine (40.5 +/- 3.4 vs. 52.2 +/- 4.2) and lower (P < 0.05) concentrations of P(i) (61.5 +/- 4.4 vs. 53.3 +/- 4.4), inosine monophosphate (0.520 +/- 0.19 vs. 0.151 +/- 0.05), and lactate (37.9 +/- 5.5 vs. 22.8 +/- 4.8) were observed. These changes were also accompanied by reduced levels of calculated free ADP, AMP, and P(i). All adaptations were fully expressed by 3 min of exercise and by 3 days of training and were independent of initial VO(2 peak) levels. Moreover, maximal activity of citrate synthase, a measure of mitochondrial capacity, was only increased with 6 days of training (5.71 +/- 0.29 vs. 7.18 +/- 0.37 mol. kg protein(-1). h(-1); P < 0. 05). These results demonstrate that metabolic adaptations to prolonged exercise occur within the first 3 days of training and during the non-steady-state period. Moreover, neither time course nor magnitude of metabolic adaptations appears to depend on increases in mitochondrial potential or on initial aerobic power.

Adaptation, Physiological↗
PubMed1999

A comparison of the reproducibility and the sensitivity to change of visual analogue scales, Borg scales, and Likert scales in normal subjects during submaximal exercise.

OBJECTIVE: To assess which subjective scale, the visual analogue scale (VAS), the Borg CR10 (Borg) scale, or the Likert scale (LS), if any, is decidedly more reproducible and sensitive to change in the assessment of symptoms. DESIGN: Prospective clinical study. SETTING: Exercise laboratory. PARTICIPANTS: Twenty-three physically active male subjects (mean +/- SD age of 30 +/- 4 years old) were recruited. INTERVENTION: Each subject attended the exercise laboratory on four occasions at intervals of 1 week. Three subjective scales were used: (1) the VAS (continuous scale); (2) the Borg scale (12 fixed points); and (3) the Likert scale (LS; 5 fixed points). Four identical submaximal tests were given (2 min at 60% maximum oxygen uptake [VO(2)max] and 6 min at 70% VO(2)max). Two tests were undertaken to assess the reproducibility of scores that were obtained with each subjective scale. Two other tests were undertaken to assess the sensitivity of each scale to a change in symptom perception: a double-blind treatment with propranolol, 80 mg, (ie, active therapy; to increase the sensation of breathlessness and general fatigue during exercise) or matching placebo. The subjective scale scores were measured at 1 min 30 s, 5 min 30 s, and 7 min 15 s of exercise. Reproducibility was defined as the proportion of total variance (ie, between-subject plus within-subject variance) explained by the between-subject variance given as a percentage. Sensitivity was defined as the effect of the active drug therapy over the variation within subjects. RESULTS: Overall, the VAS performed best in terms of reproducibility for breathlessness and general fatigue, with reproducibility coefficients as high as 78%. For sensitivity, the VAS was best for breathlessness (ratio, 2.7) and the Borg scale was most sensitive for general fatigue (ratio, 3.0). The relationships between the respective psychological and physiologic variables were reasonably stable throughout the testing procedure, with overall typical correlations of 0.73 to 0.82 CONCLUSION: This study suggests that subjective scales can reproducibly measure symptoms during steady-state exercise and can detect the effect of a drug intervention. The VAS and Borg scales appear to be the best subjective scales for this purpose.

Adrenergic beta-Antagonists↗
PubMed1999

Brain imaging studies of cocaine abuse: implications for medication development.

Contemporary in vivo brain imaging techniques confer the ability to assess brain function and structure noninvasively, and thereby can yield information to help guide the development of new treatments for substance abuse. The advantages and limitations of the major imaging modalities (positron emission tomography [PET], single photon emission computed tomography [SPECT], structural and functional magnetic resonance imaging [MRI, fMRI, respectively]) are discussed with respect to their applicability to research on cocaine abuse. The effects of acute administration of cocaine have been studied using PET and fMRI, with PET manifesting decreases in cerebral glucose metabolism and blood flow, and fMRI revealing regional effects that are correlated temporally with subjective responses. In addition, studies of drug abusers, abstinent from cocaine for various lengths of time, have revealed persistent differences in brain function and structure, especially in the frontal cortex, when compared with parameters in the brains of subjects who do not use illicit drugs of abuse. PET studies also have revealed abnormalities in markers for dopaminergic and opioid systems during withdrawal from cocaine. Moreover, studies of cue-elicited craving for cocaine demonstrate a connection between the response to drug-related stimuli and neural elements of cognition and emotion. The future directions of in vivo brain imaging to identify functional and structural alterations in the brains of cocaine abusers are discussed in relation to the development of medications to treat cocaine dependence.

Animals↗
PubMed1999

Inhibition of the MAPK pathway abrogates BCL2-mediated survival of leukemia cells after exposure to low-dose ionizing radiation.

The ability of low-dose ionizing radiation (1 Gy) to modulate the activities of the mitogen-activated protein kinase (MAPK) and Jun NH2-terminal kinase (JNK1) cascades in human myeloid leukemia (HL60/pCEP4) cells and in cells overexpressing the anti-apoptosis protein BCL2 (HL60/Bcl-2) was investigated. Radiation exposure caused prolonged (3-4 h) activation of MAPK in HL60 cells. The ability of radiation to activate the MAPK pathway was attenuated by 30% in cells overexpressing BCL2. In contrast, low-dose irradiation of HL60/pCEP4 and HL60/Bcl-2 cells failed to modulate JNK1 activity. Inhibition of the MAPK pathway by use of the specific MEK1/2 inhibitor (10 microM PD98059) in both HL60/pCEP4 and HL60/Bcl-2 cells prior to irradiation permitted a similar prolonged radiation-induced activation of JNK1. Furthermore, combined treatment with PD98059 and radiation in both cell types caused a large decrease in growth of cells in suspension culture, a large increase in apoptosis, and a 90% decline in clonogenicity when compared to either treatment alone. Reduced proliferation after combined irradiation and PD98059 treatment in both cell types correlated with reduced Cdc2 activity and arrest in G2/M phase of the cell cycle. These data demonstrate that inhibition of MEK1/2 leading to blockade of the MAPK activation increases the radiation sensitivity of HL60 cells and decreases the ability of these cells to recover from the radiation-induced arrest at the G2/M-phase cell cycle checkpoint. In addition, our data demonstrate that elevated expression of BCL2 does not abrogate the ability of inhibition of MAPK to potentiate radiation-induced cell death in HL60 cells.

Apoptosis↗
PubMed1999

One-day therapy for vaginal candidiasis. A review.

Shorter courses of therapy have been developed for most antifungal agents used for the treatment of vaginal candidiasis, including clotrimazole, econazole, isoconazole, miconazole, terconazole and fluconazole. A search of the medical literature identified 14 studies that compared single-dose therapy for vaginal candidiasis in nonpregnant women. These studies, conducted according to similar study designs, provided sufficient information to evaluate clinical and mycologic cure rates. There were few significant differences in either the clinical or mycologic cure rates of single-dose therapy, and no one therapy was consistently better than any other. Until further information is available, the choice of therapy will continue to be based on individual clinician preference.

Administration, Intravaginal↗
PubMed1999

Evidence that the apoptotic actions of etoposide are independent of c-Jun/activating protein-1-mediated transregulation.

We recently demonstrated that physiological induction of apoptosis by cytotoxic sphingolipid messengers proceeds via activating protein-1 (AP1)-dependent and AP1-independent mechanisms in U937 human monoblastic leukemia cells. Here we examine involvement of the stress-activated protein kinase (SAPK) cascade and AP1 in the initiation of apoptosis in U937 cells by podophyllotoxin-derived inhibitors of topoisomerase II. Induction of apoptotic cell death and DNA damage by treatment of U937 cells with etoposide (100 microM) was associated with phosphorylation and activation of the c-Jun NH(2)-terminal kinase (JNK1) SAPK enzymes p46 and p54-JNK2 and transient increases in expression of the transcription factor c-Jun, a primary JNK substrate. These responses were accompanied by a modest, but sustained, recruitment of the mitogen-activated protein kinases p42-extracellular signal receptor-activated kinase (ERK)1 and p44-extracellular signal receptor-activated kinase 2. The capacity of etoposide to promote double-stranded DNA degradation and cell death was unaffected by manipulations that interfere with SAPK signaling outflow through c-Jun/AP1, including: 1) pharmacological inhibition of AP1 activity by diferuloylmethane and 2) molecular ablation of normal c-Jun function by the Jun dominant-negative mutant TAM-67. Cytotoxicity of the structurally related compound teniposide was similarly unaffected. In parallel trials, the lethal actions of ceramide (but not of sphingosine) were markedly diminished by pretreatment with diferuloylmethane or expression of TAM-67, confirming the effectiveness of these interventions in suppression of SAPK/AP1-dependent apoptosis. The involvement of AP1 in the proapoptotic actions of other inhibitors of topoisomerase II activity was also evaluated. Induction of cell death by the anthracyclines daunorubicin, daunorubicin, and idarubicin was found to be insensitive to pretreatment with diferuloylmethane or expression of TAM-67. Collectively, the present data indicate that induction of apoptosis by etoposide and related inhibitors of topoisomerase II is mediated through a cell death pathway that does not require SAPK-dependent recruitment of AP1. These findings additionally suggest that activation of the SAPK represents a consequence, rather than an underlying cause, of etoposide-induced apoptosis in myeloid leukemia cells.

Antibiotics, Antineoplastic↗
PubMed1998

Evidence of a functional role for the cyclin-dependent kinase inhibitor p21(WAF1/CIP1/MDA6) in the reciprocal regulation of PKC activator-induced apoptosis and differentation in human myelomonocytic leukemia cells.

The functional role of the cyclin-dependent kinase inhibitor p21(WAF1/CIP1) in leukemic cell G1 arrest, differentiation, and apoptosis induced by two PKC activators (PMA and bryostatin 1) was examined using antisense-expressing lines [U937/p21AS(F4) and U937/p21AS(B8)]. Following incubation with 10 nM PMA (24 h), antisense-expressing cells displayed induction of p27(KIP1) but not of p21, whereas empty vector-containing cells (U937/pREP4) exhibited induction of both p21 and p27. Antisense-expressing cells were impaired in G1 arrest, dephosphorylation of the retinoblastoma protein, dephosphorylation and reduction in activity of cyclin-dependent kinase 2, and acquisition of differentiated features (e.g., plastic adherence). Bryostatin 1 induced p27 but not p21 in control cells and was less effective than PMA in initiating G1 arrest and related events. Nevertheless, disruption of p21 expression abrogated the effects of bryostatin 1 on cell cycle arrest and cellular maturation. Dysregulation of p21 did not, however, modify PMA- or bryostatin 1-mediated down-regulation of c-Myc protein. Unexpectedly, disruption of p21 failed to attenuate the net reduction in viable cell number following PMA or bryostatin 1 treatment inasmuch as impaired differentiation was accompanied by a lowered threshold for PMA- and bryostatin 1-induced apoptosis. Inhibition of p21 expression also promoted PMA- and bryostatin 1-mediated loss of mitochondrial transmembrane potential (DeltaPsim ) and release of cytochrome c into the cytosol. Together, these findings demonstrate a critical functional role for p21 in regulating myelomonocytic leukemic cell G1 arrest and differentiation following exposure to two PKC activators exhibiting disparate patterns of activity. They also suggest that following treatment with these agents, dysregulation of p21 prevents leukemic cells from engaging a normal differentiation program through a c-Myc-independent mechanism, and instead directs cells along an apoptotic pathway.

Apoptosis↗
PubMed1998

Effect of bryostatin 1 on taxol-induced apoptosis and cytotoxicity in human leukemia cells (U937).

We have examined the effects of the macrocyclic lactone protein kinase C (PKC) activator bryostatin 1 on taxol-induced apoptosis and inhibition of clonogenicity in the human monocytic leukemia cell line U937. Exposure of cells to bryostatin 1 (10 nM; 15 hr) after (but not before) a 6-hr incubation with 0.5 microM taxol significantly increased apoptosis and resulted in an approximately 3 log reduction in clonogenicity. Cell cycle analysis revealed that the increase in apoptotic cells following bryostatin 1 treatment occurred primarily in the population undergoing taxol-mediated G2M arrest. The actions of bryostatin 1 were not attributable to potentiation of taxol-induced tubulin stabilization or to a reduction in the intracellular retention of taxol. Following exposure of cells to taxol, the Bcl-2 protein displayed an alteration in mobility that was not modified appreciably by bryostatin 1 treatment. The mobility shift in Bcl-2 protein from cells exposed to taxol followed by bryostatin 1 was eliminated by treatment of lysates with the protein phosphatase 2A (PP2A); the latter effect was blocked by okadaic acid. Treatment of cells with taxol followed by bryostatin 1 did not increase the amount of total Bax (compared with treatment with taxol alone), but did increase the amount of free Bax in the supernatant fraction. Finally, the ability of bryostatin 1 to potentiate taxol-induced apoptosis in U937 cells was mimicked closely by 2'-amino-3'-methoxyflavone (PD98059), a specific inhibitor of the mitogen-activated protein kinase (MAPK) kinase (MEK). Collectively, these findings indicate that bryostatin 1 increases the susceptibility of U937 cells to taxol-induced apoptosis and inhibition of clonogenicity. They also raise the possibility that this phenomenon may involve functional alterations in Bcl-2 and/or other proteins involved in regulation of the cell death pathway.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1998

Synchronizing retinal activity in both eyes disrupts binocular map development in the optic tectum.

Spatiotemporal correlations in the pattern of spontaneous and evoked retinal ganglion cell (RGC) activity are believed to influence the topographic organization of connections throughout the developing visual system. We have tested this hypothesis by examining the effects of interfering with these potential activity cues during development on the functional organization of binocular maps in the Xenopus frog optic tectum. Paired recordings combined with cross-correlation analyses demonstrated that exposing normal frogs to a continuous 1 Hz of stroboscopic illumination synchronized the firing of all three classes of RGC projecting to the tectum and induced similar patterns of temporally correlated activity across both lobes of the nucleus. Embryonic and eye-rotated larval animals were reared until early adulthood under equivalent stroboscopic conditions. The maps formed by each RGC class in the contralateral tectum showed normal topography and stratification after strobe rearing, but with consistently enlarged multiunit receptive fields. Maps of the ipsilateral eye, formed by crossed isthmotectal axons, showed significant disorder and misalignment with direct visual input from the retina, and in the eye-rotated animals complete compensatory reorientation of these maps usually induced by this procedure failed to occur. These findings suggest that refinement of retinal arbors in the tectum and the ability of crossed isthmotectal arbors to establish binocular convergence with these retinal afferents are disrupted when they all fire together. Our data thus provide direct experimental evidence that spatiotemporal activity patterns within and between the two eyes regulate the precision of their developing connections.

Aging↗
PubMed1998

Ng-nitro-L-arginine, an NOS inhibitor, reduces tolerance to morphine in the rat locus coeruleus.

Ng-nitro-L-arginine (L-NArg), a potent nitric oxide synthase inhibitor, has been implicated as a potential mechanism for attenuating the development of tolerance to opioid drugs and for suppressing opioid withdrawal. Neurons in the locus coeruleus (LC) express opioid receptors and these neurons exhibit both tolerance to chronic administration of opioids and antagonist-precipitated withdrawal hyperactivity. This study tested the hypothesis that L-NArg would attenuate the development of opioid tolerance in LC neurons. Challenge doses of morphine were administered while recording single-cell extracellular activity in brain slices from rats who had been concurrently treated for 5 days with morphine (75 mg morphine sulfate base pellets) and L-NArg (10 mg/kg, i.p., bid). The average ED50 for morphine of cells from rats who received L-NArg injections and morphine pellets was similar to that in cells from rats who had been implanted with sham pellets (14.5-18 nM). In contrast, the average ED50 of cells from morphine pelleted animals who received saline injections was substantially higher (34.5 nM). These results demonstrate that L-NArg attenuates the development of tolerance to morphine in LC neurons.

Animals↗
PubMed1998

A comparison of physiological responses and rating of perceived exertion between high-impact and low-impact aerobic dance sessions.

The aim of this study was to compare the exercise intensity and rating of perceived exertion (RPE) of a high-impact (HIP) and a low-impact (LIP) university aerobic dance session. Ten women [mean (SD) age 22.9 (2.6) years] took part in the study. An incremental treadmill test was performed by each subject to determine maximum oxygen consumption (VO2max) and maximum heart rate (HRmax). The measured VO2max [mean (SD)] was 49.0 (7.5) ml x kg(-1) x min(-1). The subjects were randomly assigned to LIP and HIP sessions (i.e. five of the subjects participated in the HIP session first, and the other five participated in the LIP session first). In a laboratory, heart rate, oxygen uptake and RPE were measured throughout each session for each subject. Expired air was collected continuously throughout the sessions using Douglas bags (ten bags over a 30-min period). The sessions consisted of 20 min of aerobic exercise (bags 1-7) followed by 5 min of local muscular endurance exercise (bags 8 and 9) and 5 min of flexibility exercises (bag 10). The mean intensity of the aerobic section of the LIP and HIP sessions was 51.6% and 64.7% VO2max, respectively. Ninety-five percent confidence intervals for the average difference between the HIP and LIP sessions demonstrate that the %VO2max was between 12% and 14% higher for the HIP session. The mean %HRmax for the LIP and HIP sessions was 71.4% and 76.7%, respectively, with the %HRmax in the HIP session being between 5.4% and 7.2% higher on average than that of the LIP session. On average, the RPE for the aerobic section of the HIP session (12.1) was consistently higher than that of the LIP session (11.1). HIP activity has the potential to maintain/improve the aerobic fitness of its participants. According to the literature, the exercise intensity elicited by LIP activity may have a limited training effect for the population utilised in this study, and for some individuals may result in detraining. Conversely, LIP activities may be an appropriate mode of exercise for overweight and unfit individuals.

Adolescent↗
PubMed1998

Dietzia natronolimnaios sp. nov., a new member of the genus Dietzia isolated from an east African soda lake.

Two novel alkaliphilic aerobic organotrophic bacteria have been isolated from a moderately saline and alkaline East African soda lake. The new isolates grow at pH values between 6 and 10, with a pH optimum for growth of 9.0, and at a salt concentration between 0% and 10% (w/v). Phylogenetic analysis based on 16S rDNA sequence shows that these isolates are very closely related (99.6% similarity) and are members of the monospecific genus Dietzia (98.8% and 98.7% similarity). DNA/DNA hybridization revealed a relatedness of 83% between the two isolates, but only 8% between them and the type strain Dietzia maris. The G + C content as measured by thermal denaturation is 66.1 mol%. Phenotypic comparisons between D. maris and one isolate showed that they share very similar morphological and chemotaxonomic properties, but differ significantly in carbon source utilization profiles and halotolerance in alkaline medium. We propose a second species of this genus which we name Dietzia natronolimnaios (type strain 15LN1 = CBS 107.95).

Bacteria, Aerobic↗
PubMed1998

Ara-C: cellular and molecular pharmacology.

The antimetabolite cytosine arabinoside (ara-C) represents a prototype of the nucleoside analog class of antineoplastic agents and remains one of the most effective drugs used in the treatment of acute leukemia as well as other hematopoietic malignancies. The ability of ara-C to kill neoplastic cells is regulated at three distinct but interrelated levels. First, the activity of ara-C depends on conversion to its lethal triphosphate derivative, ara-CTP, a process that is influenced by multiple factors, including nucleoside transport, phosphorylation, deamination, and levels of competing metabolites, particularly dCTP. Second, the antiproliferative and lethal effects of ara-C are linked to the ability of ara-CTP to interfere with one or more DNA polymerases as well as the degree to which it is incorporated into elongating DNA strands, leading to DNA fragmentation and chain termination. Finally, the fate of the cell is ultimately determined by whether a threshold level of ara-C-mediated DNA damage is exceeded, thereby inducing apoptosis, or programmed cell death. The latter process is influenced by components of various signal transduction pathways (e.g., PKC) and expression of oncogenes (e.g., bcl-2, c-Jun), perturbations in which may significantly alter ara-C sensitivity. A better understanding of these factors could eventually lead to the development of novel therapeutic strategies capable of overcoming ara-C resistance and improving therapeutic efficacy.

Animals↗
PubMed1998

Effect of cocaine-related environmental stimuli on the spontaneous electroencephalogram in polydrug abusers.

Relationships between the spontaneous electroencephalogram (EEG), self-reports of cocaine craving, and cerebral glucose metabolism, determined using 2-[18F]fluoro-2-deoxy-D-glucose and positron emission tomography, were assessed during the presentation of either neutral or cocaine-related environmental stimuli. In cocaine users but not non-drug-abusing controls, EEG power in the alpha1 and alpha2 frequency bands was significantly lowered during presentation of the drug-related stimuli when compared with the neutral test session. Decreases in alpha1 power were negatively correlated with increases in global glucose metabolism but were not correlated with either the time course or the magnitude of craving throughout the 30-min test session. Although EEG desynchronization is related to global brain metabolism, the difference in the time courses between EEG power and craving suggests that self-reports of cue-elicited cocaine craving do not simply reflect increases in the state of cortical arousal.

Adult↗
PubMed1998

Rapid growth mutants of Escherichia coli.

If rapid growth (rap) mutants of Escherichia coli could be obtained, these might prove a valuable contribution to fields as diverse as growth rate control, biotechnology and the regulation of the bacterial cell cycle. To obtain rap mutants, a dnaQ mutator strain was grown for four and a half days continuously in batch culture. At the end of the selection period, there was no significant change in growth rate. The result means that selecting rap mutants may require an alternative strategy and a number of such alternatives are discussed.

Bacteriological Techniques↗
PubMed1998

The roles of signaling by the p42/p44 mitogen-activated protein (MAP) kinase pathway; a potential route to radio- and chemo-sensitization of tumor cells resulting in the induction of apoptosis and loss of clonogenicity.

During the last 10 years, multiple signal transduction pathways within cells have been discovered. These pathways have been linked to the regulation of many diverse cellular events such as proliferation, senescence, differentiation and apoptosis. This review will focus upon the many roles of signaling by the p42/p44 mitogen-activated protein (MAP) kinase pathway. Recent evidence suggests that signaling by the MAP kinase pathway can both enhance proliferation by increased expression of molecules such as cyclin D1, but also cause growth arrest by increased expression of molecules such as the cyclin kinase inhibitor protein p21(Cip-1/MDA6/WAF1). These differential effects on growth have been correlated to the amplitude and duration of the MAP kinase activity signal. Furthermore several laboratories are reporting data suggesting that inhibition of the MAP kinase pathway, as well as a family of upstream MAP kinase activators, the protein kinase C family, represent an important route to both radio- and chemo-sensitization of tumor cells. Herein, we describe the historical discovery and characterization of the MAP kinase pathway. In addition we describe potential mechanisms by which inhibition of protein kinase C, the MAP kinase pathway, and potentially of p21(Cip-1/MDA6/WAF1) expression, may alter the sensitivities of leukemic and carcinoma cells to cytotoxic insults, leading to increased apoptosis and loss of clonogenicity.

Calcium-Calmodulin-Dependent Protein Kinases↗
PubMed1998

The reproducibility of symptoms during a submaximal exercise test in chronic heart failure.

AIMS: The aim of this study was to evaluate the use of a submaximal test with a symptom limited endpoint and to measure the reproducibility of symptoms in patients with CHF. METHODS: Ten patients with chronic heart failure were studied. Based on two maximal treadmill tests an individual protocol using a constant work rate at a submaximal intensity was derived. The projected maximum treadmill time for the constant workrate was between 8 and 17 min. Tests were carried out 1, 2, 4 and 6 weeks after the maximum tests. Every 2.5 min during the submaximal test patients recorded their symptoms of breathlessness and fatigue using computer automated visual analogue (VAS) and Borg CR10 scales. The measure of reproducibility used was the proportion of total variability explained by the between subject variability. RESULTS: Using the VAS scale, general fatigue was reasonably reproducible ranging from 77-86%. For VAS breathlessness reproducibility ranged from 66% to 83%. Reproducibility for breathlessness and fatigue for the Borg CR10 scale was much lower than the VAS scale. Reproducibility for the treadmill times was 51% but increased to 76% if one test of one subject was excluded. CONCLUSIONS: The use of the VAS during submaximal exercise offers a useful means of evaluating symptoms in CHF and potentially their response to treatment. These findings show that individual submaximal protocols can be easily prescribed for CHF patients. Using such an approach, clinically desirable tests lasting around 12 min can be developed. These tests are reasonably reproducible and may provide a useful means of assessing patient disability and the impact of treatment.

Aged↗