Biomedical subjects

C R France

Publications and source records attributed to C R France.

11 recordsLinked to original sources

PubMed1999

A comparison of diffuse noxious inhibitory controls in men and women.

Results from clinical and experimental pain studies provide consistent evidence of sex differences in pain perception, with women reporting more clinical pain and demonstrating lower pain threshold and tolerance levels than men. The present study was designed to assess the notion that sex differences in pain perception may be related to differential activation of supraspinal pain modulation systems. Specifically, the phenomenon of diffuse noxious inhibitory controls (DNIC) was examined in healthy young adult men (n = 39) and women (n = 44) using repeated assessment of nociceptive flexion reflex activity before, during and after exposure to forearm ischemia. Consistent with previous research, women exhibited significantly lower nociceptive flexion reflex thresholds than men, and reported significantly greater pain in response to both forearm ischemia and repeated electrocutaneous stimulation required to elicit the nociceptive flexion reflex. Application of forearm ischemia was associated with a significant decrease in nociceptive flexion reflex activity in both men and women, however, the degree of attenuation of nociceptive flexion reflex activity was not significantly different between the sexes. These findings suggest that men and women exhibit similar activation of diffuse noxious inhibitory controls, but they do not exclude the possibility of sex differences in other forms of central pain modulation.

Adolescent↗

PubMed1999

Caffeine attenuates vasovagal reactions in female first-time blood donors.

The experience of vasovagal reactions during blood donation (e.g., faintness, dizziness, lightheadedness) can be a deterrent to repeat donation. Because these reactions are associated with decreases in blood pressure, caffeine was examined as a potential modulator of vasovagal reactions by virtue of its pressor effects. Using a randomized, double-blind design, 62 female undergraduate 1st-time blood donors received either 0, 125, or 250 mg of caffeine prior to blood donation. Participants who received 250 mg of caffeine had lower scores on the Blood Donation Reactions Inventory, required fewer interventions by phlebotomists for negative reactions, and reported a greater likelihood of repeat donation than participants who received placebo. These findings suggest that a moderate dose of caffeine attenuates negative reactions in novice female blood donors and may increase the likelihood of repeat donations.

Adult↗

PubMed1999

Decreased pain perception and risk for hypertension: considering a common physiological mechanism.

For almost two decades, researchers have demonstrated that hypertension is reliably associated with decreased perception of pain. More recently, a growing body of evidence has begun to suggest that hypoalgesia is not a consequence of high blood pressure, as the phenomenon precedes the onset of hypertension in individuals at risk for the disorder. This article provides a review of empirical evidence of decreased pain perception in normotensive persons with a family history of hypertension, elevated resting blood pressure, or exaggerated cardiovascular reactivity to stress. Based on the existing evidence, hypoalgesia is argued to be a correlate of dysregulation of central nervous system structures involved in both pain control and cardiovascular regulation in individuals who are genetically predisposed to develop high blood pressure. As such, hypoalgesia may serve as a valuable method of identifying individuals at greatest risk for hypertension.

Animals↗

PubMed1998

Assessing parental history of hypertension: father (and mother) knows best!

In hypertensive risk studies, offspring reports are often used to establish parental history of hypertension. This method is simple and less costly than contacting parents and has been reported to be > or = 84% accurate when compared with parental confirmation. The present study examined two components that contribute to overall accuracy: sensitivity (correct identification of high blood pressure) and specificity (correct identification of normal blood pressure). Undergraduate volunteers (282 women, 211 men) provided parental blood pressure information, and then blood pressure history questionnaires were mailed to their biological parents. Comparison of offspring and parent reports revealed a combination of high specificity (92.9%) and low sensitivity (68.2%), suggesting that offspring reports may be misleading when attempting to identify hypertensive parents.

Adolescent↗

PubMed1998

Computerized depression screening and awareness.

The DEPRESSION Awareness, Recognition and Treatment (D/ART) program under the sponsorship of the National Institutes of Health has made consistent efforts to help educate many communities around the nation about depression. One important aspect of this effort includes offering free screening for depression to the general public. Since new technology often promotes curiosity and interest, a computerized depression screening and awareness program was created to use at fairs and other local events. Individuals who participated completed a computerized version of the Center for Epidemiological Studies Depressed Mood Scale (CES-D) and then received a one page printout that described the common symptoms of depression, a score indicative of their level of depressed mood, a brief explanation of the score, and a telephone number where additional information could be obtained. This paper details the construction of the computerized version of the CES-D including an evaluation of psychometric properties and consumer satisfaction with the program.

Adult↗

PubMed1997

Change mechanisms associated with combined relaxation/EMG biofeedback training for chronic tension headache.

Therapeutic mechanisms hypothesized to underlie improvements in tension headache activity achieved with combined relaxation and electromyographic (EMG) biofeedback therapy were examined. These therapeutic mechanisms included (1) changes in EMG activity in frontal and trapezii muscles, (2) changes in central pain modulation as indexed by the duration of the second exteroceptive silent period (ES2), and (3) changes in headache locus of control and self-efficacy. Forty-four young adults with chronic tension-type headaches were assigned either to six sessions of relaxation and EMG biofeedback training (N = 30) or to an assessment only control group (N = 14) that required three assessment sessions. Measures of self-efficacy and locus of control were collected at pre- and posttreatment, and ES2 was evaluated at the beginning and end of the first, third, and last session. EMG was monitored before, during, and following training trials. Relaxation/EMG biofeedback training effectively reduced headache activity: 51.7% of subjects who received relaxation/biofeedback therapy recorded at least a 50% reduction in headache activity following treatment, while controls failed to improve on any measure. Improvements in headache activity in treated subjects were correlated with increases in self-efficacy induced by biofeedback training but not with changes in EMG activity or in ES2 durations. These results provide additional support for the hypothesis that cognitive changes underlie the effectiveness of relaxation and biofeedback therapies, at least in young adult tension-type headache sufferers.

Adolescent↗

PubMed1996

Predicting vasovagal reactions in volunteer blood donors.

Measures of blood and injury sensitivity, pain sensitivity, and anxiety were examined as potential predictors of syncope and related reactions in 215 volunteer blood donors. The Blood and Injury Fears subscale of the Fear Survey Schedule was the best predictor for first-time donors (r[84] = 0.43, p < 0.001), whereas the Mutilation Questionnaire was the best predictor for experienced donors (r[127] = 0.31, p < 0.01). In contrast with previous studies, few significant predictions were observed for demographic variables (e.g., age, body mass index, or number of previous donations), suggesting that psychological measures may be better suited to the task of identifying high risk donors.

Adolescent↗

PubMed1996

Resting systolic blood pressure, parental history of hypertension, and sensitivity to noxious stimuli.

Increased nociceptive thresholds have been reported in hypertensive rats and humans, and also in normotensive humans at risk for developing hypertension by virtue of elevated resting blood pressure levels or a family history of hypertension. Because risk for hypertension may be more accurately predicted by a combination of risk factors, the present study examined the pain sensitivity of young adult males as a function of resting systolic blood pressure and family history of hypertension. Cold pressor and forearm ischemia tasks were administered in a counterbalanced order. Pain was assessed using numerical rating scales of intensity and unpleasantness during the tasks and the McGill Pain Questionnaire immediately following the tasks. Individuals with a parental history of hypertension obtained significantly lower Pain Rating Index scores on the McGill Pain Questionnaire for both tasks, and also reported significantly lower pain on both numerical rating scales during the ischemic task. No significant relationship was observed between resting systolic blood pressure and measures of pain sensitivity.

Adult↗

PubMed1996

Exteroceptive suppression of temporalis and masseter muscle activity is enhanced in offspring of hypertensives.

Exteroceptive suppression of temporalis and masseter muscle activity was examined in young men with and without a parental history of hypertension. Recent clinical studies suggest that the second exteroceptive suppression period is attenuated in several chronic pain disorders and that this brainstem reflex may serve as a noninvasive index of endogenous pain control. In the present study, offspring of hypertensives exhibited a significant protraction of the late exteroceptive suppression period for both muscle sites, suggesting that the decreased pain sensitivity previously observed in individuals at risk for hypertension may be related to enhanced central pain modulation.

Electromyography↗

PubMed1995

Parental history of hypertension and enhanced cardiovascular reactivity are associated with decreased pain ratings.

Ischemic pain was examined in adult males with and without a parental history of hypertension. Blood pressure and heart rate were recorded during baseline, cold pressor, and ischemia. Repeated pain ratings were obtained during cold pressor and ischemia, and the McGill Pain Questionnaire was completed after each stressor. A median split was used to identify high and low mean arterial pressure and heart rate reactors to cold pressor. Parental history of hypertension, high heart rate reactivity, and high mean arterial pressure reactivity were each associated with significantly lower ischemic pain ratings on the McGill Pain Questionnaire, suggesting that risk for hypertension is associated with hypoalgesia in normotensives.

Adult↗

PubMed1994

Dezinamide for partial seizures: results of an n-of-1 design trial.

BACKGROUND: Dezinamide (DZM, ADD 94057) is a potential antiepileptic drug that binds to the voltage-sensitive sodium channel and showed preliminary evidence of efficacy and safety in an open-label study. METHODS: Our double-blind, placebo-controlled trial at two sites used an n-of-1 (single-patient) design. All 15 patients had medically intractable partial-onset seizures and were comedicated with phenytoin (PHT) only. Treatment was for six 5-week periods (three active paired with three placebo in random sequence). Assuming nonlinear kinetics, we used an initial pharmacokinetic profile to estimate dosages for reaching target plasma concentrations of DZM. RESULTS: Statistically significant seizure reduction was found by both a randomization test (p = 0.0025) and a signed rank test (p = 0.048). Median seizure frequency decreased 37.9%, and 40% of patients had > 50% seizure reduction, both compared with placebo. Pharmacokinetic predictions were not accurate; mean plasma concentrations fell well below target values. Plasma PHT concentrations increased (mean = 17.1%) during DZM treatment. The most common adverse experiences were fatigue, light-headedness, and abnormal gait; five patients required DZM dosage reductions. CONCLUSIONS: DZM showed minimal clinical toxicity and significant efficacy despite lower plasma concentrations than predicted by pharmacokinetics. This trial establishes the suitability of the n-of-1 design to investigational antiepileptic drug trials.

Adult↗