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Biomedical subjects

D R McLeod

Publications and source records attributed to D R McLeod.

At least 37 records · Page 2Linked to original sources
PubMed1994

Muscle tension in generalized anxiety disorder: elevated muscle tonus or agitated movement?

The purpose of this study was to investigate the amplitude characteristics of frontalis and gastrocnemius electromyographic (EMG) activity in clinically anxious and nonanxious populations. Eighteen women with generalized anxiety disorder (GAD) and 19 nonanxious women were compared during baseline, laboratory stressor, and recovery conditions. EMG mean levels were greater for the GAD group, but there were no group differences in EMG skewness. During the stressor the GAD group had a significant reduction in frontalis EMG variability. Gastrocnemius muscle activity for both groups during the stressor condition increased in mean levels and variability while decreasing in skewness. These results indicate that clinically anxious individuals have elevated muscular tonus and have reduced variability in frontalis activity during stressful tasks. Also, the gastrocnemius muscle exhibited a stressor reactivity, whereas the frontalis did not. This study presents an approach to EMG analysis that could be useful in distinguishing unique features of anxiety as well as other emotional disorders.

Adolescent↗
PubMed1994

Family history of alcoholism in women with generalized anxiety disorder who have premenstrual syndrome: patient reports of premenstrual alcohol consumption and symptoms of anxiety.

This study sought to determine whether family history of alcoholism is related to patient reports of premenstrual alcohol consumption and whether family history of alcoholism is related to severity of anxiety-related symptoms, in women who suffer simultaneously from both premenstrual syndrome and generalized anxiety disorder. Fifty-four women with generalized anxiety disorder and prospectively demonstrated premenstrual syndrome were questioned about family history of alcoholism and alcohol consumption patterns across the menstrual cycle. Seventy-six percent of the sample reported having an alcoholic first- or second-degree relative. Furthermore, 74% of those women having a paternal-side family history of alcoholism, but only 22% of those without such a family history, reported increased alcohol consumption premenstrually. Forty-one of these women were assessed by means of psychiatric rating scales during both the premenstrual and follicular phases of the menstrual cycle. During the premenstrual, but not the follicular, phase of the menstrual cycle, women with a paternal-side family history of alcoholism experienced more severe anxiety-related somatic, but not psychic, symptoms of anxiety, than those without such a family history. These findings suggest that family history of alcoholism may be related to premenstrual alcohol consumption patterns and to the severity of premenstrually experienced somatic symptoms of anxiety in women with premenstrual syndrome, and that these women may be self-medicating with alcohol.

Adult↗
PubMed1993

Recommendations on the use of folic acid supplementation to prevent the recurrence of neural tube defects. Clinical Teratology Committee, Canadian College of Medical Geneticists.

OBJECTIVE: To prevent the recurrence of neural tube defects (NTDs) in families at increased risk of having offspring with NTDs with the use of periconceptional folic acid supplementation. OPTIONS: Genetic counselling and prenatal diagnosis of NTDs. OUTCOMES: NTDs cause stillbirth, neonatal death and severe disabilities. The cost for medical care and rehabilitation in the first 10 years of life of a child with spina bifida cystica was estimated to be $42,507 in 1987. EVIDENCE: The authors reviewed the medical literature, communicated with investigators from key studies, reviewed policy recommendations from other organizations and drew on their own expertise. A recent multicentre randomized controlled trial showed that among women at high risk of having a child with an NTD those who received 4 mg/d of folic acid had 72% fewer cases of NTD-affected offspring than nonsupplemented women. Two previous intervention studies also demonstrated that folic acid supplementation was effective in reducing the rate of NTD recurrence. Several retrospective studies support this conclusion. VALUES: Recommendations are the consensus of the Clinical Teratology Committee of the Canadian College of Medical Geneticists (CCMG) and have been approved by the CCMG Board. The committee believes that primary prevention of NTDs is preferable to treatment or to prenatal detection and abortion. BENEFITS, HARMS AND COSTS: Folic acid supplementation should result in fewer NTDs among infants in Canada and ancillary savings in medical costs. The recommended dosage of folic acid is not known to be associated with adverse effects. Higher dosages of folic acid may make vitamin B12 deficiency difficult to diagnose and may alter seizure frequency in patients with epilepsy due to drug interactions with anticonvulsants. RECOMMENDATIONS: A minimum dosage of folic acid of 0.8 mg/d, not to exceed 5.0 mg/d, is recommended along with a well-balanced, nutritious diet for all women who are at increased risk of having offspring with NTDs and who are planning a pregnancy or may become pregnant. Supplementation should begin before conception and continue for at least 10 to 12 weeks of pregnancy. VALIDATION: These guidelines are similar to those of the Society of Obstetricians and Gynaecologists of Canada, the US Centers for Disease Control and Prevention and the Department of Health in Britain. SPONSORS: These guidelines were developed by the CCMG Clinical Teratology Committee and endorsed by the Board of the CCMG. No funding for the development of these guidelines was obtained from any other sources.

Female↗
PubMed1993

Metacarpophalangeal pattern profile analysis in Williams syndrome.

Many patients with Williams syndrome (WS) are not diagnosed until they are old enough to demonstrate the characteristic personality and facial changes. A number of these changes are quite subtle and none of them is present in all affected individuals. The cause of WS remains obscure and consequently, there are no cytogenetic, biochemical, or molecular studies to help in the diagnosis of patients in whom the diagnosis is uncertain. We have generated a mean WS metacarpophalangeal pattern profile (MCPP) on 21 clinically diagnosed individuals with WS. This mean syndrome profile shows that WS hands are smaller than average age-matched control hands and that the distal phalanx of the thumb is disproportionately large with respect to the rest of the hand. A mathematical model, which effectively discriminates WS patients from unaffected control individuals, was developed using discriminant analysis of the MCPP data. Of the 21 WS patients classified by this method, only 2 were misclassified as "normal." Similarly, 2 of the 24 control individuals were misclassified as "WS," yielding an over-all successful classification rate of 91%.

Abnormalities, Multiple↗
PubMed1993

The influence of premenstrual syndrome on ratings of anxiety in women with generalized anxiety disorder.

During the premenstrual and follicular phases of the menstrual cycle, 41 women who had generalized anxiety disorder (GAD) plus premenstrual syndrome (PMS) were assessed with psychiatric rating scales and compared with 21 GAD patients without PMS and 19 controls. The latter two groups were rated only once, in the typical open-ended manner. Symptoms during both phases of the menstrual cycle were more severe in the GAD + PMS patients than in the controls and were more severe during the premenstruum. For the GAD + PMS patients, ratings obtained in the typical open-ended manner were influenced by how patients felt during the premenstruum. Thus, the assessment of women with GAD + PMS may be complicated by cyclical fluctuations in symptom severity, and ratings obtained in the typical manner may be influenced disproportionately by how these patients feel premenstrually.

Adult↗
PubMed1993

Effect of fluvoxamine on panic disorder.

Several reports suggest that selective serotonin reuptake blockers are helpful in the treatment of panic disorder. The aim of the study was to compare fluvoxamine with placebo in 50 panic disorder patients by using an 8-week, double-blind, parallel-groups design. Weekly assessment included a panic attack diary (frequency and severity), the Montgomery-Asberg Depression Scale, the Clinical Anxiety Scale, and the Sheehan Disability Scale. Although both groups improved on all measures, the fluvoxamine group experienced significantly less frequent major panic attacks from the third week on and significantly lower ratings on anxiety, depression, and disability from the sixth week on. Mean ratings of the severity of major and the severity and frequency of minor attacks were not affected differently by fluvoxamine and placebo. At the end of the study, significantly more patients on fluvoxamine were free of major and minor panic attacks. The results indicate that: (1) the administration of fluvoxamine, as compared with placebo, led to a significant reduction in the number of panic attacks. (2) The severity of panic attacks was not affected by fluvoxamine. (3) The effect of fluvoxamine on anxiety, depressive mood, and disability differed from placebo only after 6 weeks of treatment, after which the placebo group showed either no further improvement or a reversal of symptoms. (4) Participation in a drug study, even without additional psychotherapy, led to significant improvement in all patients.

Adult↗
PubMed1993

Symptoms and physiologic manifestations in obsessive compulsive patients before and after treatment with clomipramine.

BACKGROUND: Anxiety and hyperarousal constitute important aspects of obsessive compulsive disorder (OCD). This study examined the effects of clomipramine on symptoms, arousal-related physiologic states, and stress reactions in OCD patients. METHOD: Twenty-five OCD patients were randomly assigned to a clomipramine or placebo group and were assessed for 10 weeks using a double-blind parallel design. They were assessed clinically with the Yale-Brown Obsessive Compulsive Scale, the National Institute of Mental Health Global Obsessive-Compulsive Scale, the patient- and investigator-rated Global Improvement Scales, and the Hamilton Rating Scale for Depression. Prior to treatment, and again during the last day of medication, physiologic states (heart rate, respiration, skin conductance, blood pressure, and EMG) were measured at rest and during both nonspecific (psychomotor tasks) and pathology-specific (visualization) stressors. RESULTS: Patients taking clomipramine, but not those taking placebo, improved significantly on all clinical measures. With the exception of heart rate, treatment did not affect resting physiologic states. Heart rate increased in patients taking clomipramine and decreased in patients taking placebo. Autonomic reactivity to nonspecific and to pathology-specific stressors was attenuated by clomipramine, but not by placebo. CONCLUSION: Clinical improvement on clomipramine treatment was independent of the physiologic state of the patients and was not associated with autonomic down-regulation. The attenuation of autonomic reactivity to stressors appears not to be pathology-specific but may reflect either a direct pharmacologic effect of clomipramine on the autonomic nervous system or a heightened indifference to psychological stressors in general.

Adult↗
PubMed1993

A new variant of lethal neonatal short-limbed platyspondylic dwarfism.

This article describes an unusual skeletal dysplasia in a male fetus diagnosed by ultrasound at 18 weeks of gestation. The clinical and radiologic findings resemble thanatophoric dysplasia. Histologic examination revealed abnormalities in the resting cartilage, physeal growth plate, and bone. The resting cartilage contained peculiar large chondrocytes with huge lacunae. The growth plate revealed absence of column formation and hypertrophic vacuolated chondrocytes extending far into the metaphyseal bone trabeculae. The bone was hypercellular with absence of lamellar bone. The cortical bone was scanty and woven. The histopathologic features are, therefore, unique and differ from all other well-recognized varieties of short-limbed platyspondylic dwarfism.

Bone and Bones↗
PubMed1992

Asymmetry quantification utilizing hand radiographs.

Asymmetry can be either directional or fluctuating. Detection of abnormal amounts of asymmetry has important implications for clinical diagnosis, but measurement of subtle levels is very difficult. We describe a method and normative values for asymmetry quantification using hand radiographs.

Adult↗
PubMed1992

Effects of alprazolam and imipramine on parasympathetic cardiac control in patients with generalized anxiety disorder.

A noninvasive measure was used to assess the effects of alprazolam, imipramine and placebo on parasympathetic (vagal) cardiac control following 6-weeks of medication in patients with generalized anxiety disorder. Flexible dosage at therapeutic levels resulted in increased heart rate and blood pressure and in decreased cardiac vagal control in patients receiving imipramine but not alprazolam or placebo. About 50% of the variance in heart rate changes and changes in mean arterial blood pressure following treatment with imipramine could be accounted for by changes in cardiac vagal control. Decreased cardiac vagal control can now be added to the list of cardiovascular changes seen following several weeks of treatment with imipramine.

Adult↗
PubMed1991

The effects of NMDA receptor blockade on the acquisition of a conditioned emotional response.

Excitatory amino acids, acting at the N-methyl-d-aspartate (NMDA) receptor, have been postulated to play an important role in the acquisition of behavior (learning). Previous studies have shown that some forms of response acquisition can be impaired by drugs that block the NMDA receptor. To determine whether excitatory amino acid blockade could also affect the ability to acquire an emotional response, the effects of the noncompetitive NMDA receptor antagonist MK-801 were studied on the development of response suppression under a conditioned emotional response (CER) procedure in the rat. The CER procedure progressively suppressed responding when saline was given prior to the eight daily sessions over which animals were initially exposed. Daily treatment with MK-801 blocked the development of response suppression. Thus, these data are consistent with the notion that excitatory amino acid blockade prevents or diminishes the development of a learned emotional response. This suggests a potential role for this receptor in the development of anxiety-related disorders in humans.

Animals↗
PubMed1991

Psychophysiological response patterns in panic disorder.

To determine whether panic disorder patients exhibit physiological hyperarousal during rest or during mild, non-panic-inducing stress, 18 patients who experienced frequent panic attacks were compared with nonanxious controls on a battery of physiological assessments. During baseline, patients with panic disorder exhibited higher forehead electromyographic activity, higher systolic blood pressure and higher heart rates than non-anxious volunteers. During psychological stress, heart rate and systolic blood pressure rose more in patients with panic disorder than in nonanxious controls. The skin conductance response, however, was greater and more variable in the nonanxious controls. The results suggest that panic disorder patients with frequent panic attacks exhibit heightened cardiovascular arousal and decreased electrodermal flexibility than nonanxious people, even in nonthreatening situations.

Adult↗
PubMed1991

Pallister-Killian syndrome: additional manifestations of cleft palate and sacral appendage.

We report a case of Pallister-Killian syndrome in a 28 week gestation infant. In addition to the characteristic phenotype, this patient had a cleft palate, diaphragmatic hernia, sacral appendage, and imperforate anus. The lymphocyte karyotype showed 96% 46,XX/4% 47,XX+i (12p) and the fibroblast karyotype 47,XX,+marker (presumed i(12p]. Fibroblast cytogenetic studies should be considered in all cases of diaphragmatic hernia associated with other malformations.

Abnormalities, Multiple↗
PubMed1990

Treatment effects of alprazolam and imipramine: physiological versus subjective changes in patients with generalized anxiety disorder.

The correspondence between changes in physiological activity and somatic symptom reports was assessed in generalized anxiety disorder patients treated with alprazolam or imipramine. After 6 weeks, the two medications produced comparable reductions in self-reported somatic symptoms. However, patients taking alprazolam showed decreases in systolic blood pressure, epinephrine, and norepinephrine, and patients taking imipramine showed increases in heart rate, blood pressure, electromyographic activity, and norepinephrine. Thus, though the physiological changes associated with alprazolam treatment were consistent with changes in symptom reports, treatment with imipramine produced a desynchrony: patients reported significant decreases in cardiovascular symptoms and muscle tension in spite of the fact that heart rate, blood pressure, and electromyographic activity increased. Possible explanations for this counterintuitive phenomenon are discussed.

Adult↗
PubMed1990

Chromosome 6q deletions: a report of two additional cases and a review of the literature.

Here we report on two additional cases of distal 6q deletions with one case showing a terminal deletion of chromosome 6 (46,XY, del(6)(pter----q26:)) and one case showing an interstitial deletion of chromosome 6 (46,XY, del(6)(pter----q23::q25----qter)). The association of retinal abnormalities in 6q deletions is supported, and the additional manifestations of skin hyperextensibility, sacral abnormality, and imperforate anus are described.

Abnormalities, Multiple↗
PubMed1990

Apathy and indifference in patients on fluvoxamine and fluoxetine.

Apathy, indifference, loss of initiative, or disinhibition (without concurrent sedation or hypomania) were observed among five patients receiving the serotonin reuptake blocking antidepressants fluvoxamine or fluoxetine. These effects appeared to be dose related. They disappeared rapidly when the dose of fluvoxamine, which has a short half-life, was reduced. Fluoxetine, which has a long half-life, was more difficult to titrate. A possible relationship between mild drug-induced indifference and the therapeutic effects of serotonin reuptake blocking medication in anxiety disorders is discussed.

Adult↗