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Biomedical subjects

J W Mason

Publications and source records attributed to J W Mason.

At least 19 recordsLinked to original sources
PubMed1992

Comparison of ST depression recorded by Holter monitors and 12-lead ECGs during coronary angiography and exercise testing.

Data from previous studies are debatable regarding whether Holter monitors are a reliable electrocardiographic indicator of ischemia, for which the 12-lead electrocardiogram (ECG) is the standard. Simultaneous 12-lead and Holter ECGs were performed on 30 patients with typical angina pectoris during coronary angiography or exercise testing. ST depression recorded by both methods was directly compared, using the 12-lead ECG as the reference. The Holter tapes were also scanned by two automated ST analysis programs and the results were compared to 12-lead ECGs. Only 66 of the 178 12-lead ECG ST depression events were also present on the Holter recordings (37.1% Holter sensitivity). ST depression was underestimated by the Holter recordings compared to the 12-lead ECGs (p < 0.0001). The majority (67.0%) of ST depression events identified by one computer program were false positive events. The degree of ST depression was overestimated compared to 12-lead ECGs by the second program (p = 0.0033). Holter-detected ST depression may not be a reliable ECG indicator of myocardial ischemia.

Adult↗
PubMed1992

Urinary catecholamine excretion and severity of PTSD symptoms in Vietnam combat veterans.

In the present study, we replicated and extended our previous findings of increased 24-hour urinary catecholamine excretion in posttraumatic stress disorder (PTSD). Dopamine, norepinephrine, and epinephrine concentrations were measured in 22 male patients with PTSD (14 inpatients and eight outpatients) and in 16 nonpsychiatric normal males. The PTSD inpatients showed significantly higher excretion of all three catecholamines compared with both outpatients with PTSD and normal controls. Dopamine and norepinephrine, but not epinephrine, levels were significantly correlated with severity of PTSD symptoms in the PTSD group as a whole. In particular, these catecholamines seemed related to intrusive symptoms. None of the catecholamines were correlated with severity of depression. The findings support the hypothesis of an enhanced sympathetic nervous system activation in PTSD, and suggest that increased sympathetic arousal may be closely linked to severity of certain PTSD symptom clusters.

Ambulatory Care↗
PubMed1991

Hypothalamic-pituitary-adrenal dysfunction in posttraumatic stress disorder.

Neuroendocrine studies examining the hypothalamic-pituitary-adrenal (HPA) axis under baseline conditions and in response to neuroendocrine challenges have supported the hypothesis of altered HPA functioning in posttraumatic stress disorder (PTSD). However, to date, there is much debate concerning the nature of HPA changes in PTSD. Furthermore, in studies showing parallel findings in PTSD and major depressive disorder there is controversy regarding whether the HPA alterations suggest a specific pathophysiology of PTSD, or, rather, reflect comorbid major depressive disorder. This review summarizes findings of HPA axis dysfunction in both PTSD and major depressive disorder, and shows distinct patterns of HPA changes, which are probably due to different mechanisms of action for cortisol and its regulatory factors.

Adrenocorticotropic Hormone↗
PubMed1991

Multidimensional hormonal discrimination of paranoid schizophrenic from bipolar manic patients.

The search for biological markers of psychiatric disorders has traditionally involved univariate approaches, usually focusing upon one measure at a time, and to date has been primarily directed towards the assessment of depressive rather than psychotic illnesses. The present study explores a multidimensional psychoendocrine strategy, using a profile of five hormones, including cortisol, epinephrine, norepinephrine, testosterone, and free thyroxine, and is directed at the differentiation of two major psychotic illnesses, bipolar manic disorder and paranoid schizophrenia. When the levels of these hormones were assessed at admission and biweekly during hospitalization, the mean values for all five hormones were found to differ markedly between the two diagnostic groups. There was, however, always a zone of overlap in levels between the two groups when each of the five hormones were viewed individually, so that at best only about 70% of patients were correctly separated by diagnostic group using any single hormone alone. By contrast, multivariate approaches combining mean values of three or more hormones, using either stepwise discriminant analysis or multidimensional scaling, yielded 95% correct classification of the two diagnostic groups. Similar but not quite as great accuracy of classification was achieved with only the initial hormone sample obtained at the time of hospital admission. These preliminary findings provide encouragement for further exploration of multidimensional hormonal strategies in the search for useful biological criteria to assist in the diagnosis of psychiatric disorders.

Adult↗
PubMed1991

Spontaneous variability of ventricular arrhythmias in patients with chronic heart failure.

Spontaneous variability of ventricular arrhythmia in patients with chronic heart failure is not well described. We measured this variability in 23 consecutive patients with chronic heart failure who were prospectively enrolled in the placebo limb of a trial concerned with treatment of heart failure. Patients underwent from one to three periods of ambulatory monitoring separated by 1 to 3 months while they were not receiving antiarrhythmic drug treatment. The variability in frequency of premature ventricular complexes (PVCs) was determined at interrecording intervals of 1, 2, and 3 months. The percentage reductions in total PVCs required to exceed the 95% confidence limits of spontaneous variability at these intervals were 91%, 90%, and 97%, respectively. Corresponding values for repetitive beats (beats in couplets and beats in ventricular tachycardia events) were 98%, 80%, and 97% and for ventricular tachycardia events 98%, 83%, and 98%, respectively. The percentage increases in total PVCs, repetitive beats, and ventricular tachycardia events required to identify aggravation of arrhythmia in this study population were 1301%, 4050%, and 6147%, respectively, at 1-month intervals and 2950%, 2868%, and 5938%, respectively, at 3-month intervals. The percentage reductions required to show a true drug effect at 2- and 3-month intervals were 63% and 84% for patients with an ejection fraction less than 0.22 and 89% and 98% for those with an ejection fraction greater than or equal to 0.22 (p less than 0.05 for both). Ventricular arrhythmia would have been missed in 6 (26%) of the 23 patients if only one screening ambulatory recording was available. Thus marked variability in PVCs occurs in patients with chronic heart failure.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

Low urinary cortisol excretion in patients with posttraumatic stress disorder.

In the present study, we replicated and extended our previous findings of low urinary free-cortisol levels in PTSD. Cortisol was measured in 16 male patients (nine inpatients, seven outpatients) with posttraumatic stress disorder (PTSD) and in 16 nonpsychiatric control subjects. The mean cortisol level in the PTSD group was significantly lower, and the range narrower, than that observed in control subjects. Low cortisol in PTSD did not seem to be related to the presence or absence of major depressive disorder or to overall psychiatric symptomatology as assessed by the sum Brief Psychiatric Rating Scale score. In the outpatient group, there was a relationship between PTSD symptomatology and cortisol levels. The findings suggests a physiological adaptation of the hypothalamic-pituitary-adrenal axis to chronic stress.

Adult↗
PubMed1989

Possible subtypes of affective disorder suggested by differences in cerebral laterality and testosterone. A preliminary report.

Two language-related dichotic listening tests of cerebral laterality were used to divide a group of 18 hospitalized patients with affective disorder into two subgroups of nine. The groups proved to differ in serum testosterone levels at the time of admission and in mean serum testosterone levels throughout hospitalization. Moreover, there was a positive correlation between testosterone level and symptom severity in one of the laterality-defined subgroups and a negative correlation in the other. These data (1) provide new evidence of pathophysiological heterogeneity within a single general diagnostic group; (2) suggest that noninvasive, inexpensive, and easily administered dichotic listening tests may be able to define pathophysiologically meaningful subgroups; and (3) suggest a role for testosterone-related alterations in left hemisphere function in the pathogeneses of some affective disorders.

Adult↗
PubMed1989

Comparison of three techniques for percutaneous balloon aortic valvuloplasty of aortic stenosis in adults.

Three different techniques for percutaneous balloon aortic valvuloplasty h have been described: retrograde single balloon, retrograde double balloon, and antegrade techniques. This report describes our experience using the three techniques in twenty-five consecutive procedures. All techniques resulted in a significant decrease in transvalvular pressure gradient and an increase in calculated aortic valve area, without significant difference among the three. There was no increase in the degree of aortic regurgitation after valvuloplasty by any of the techniques. Vascular complications occurred only with the retrograde double balloon technique. Cardiac tamponade during balloon inflation occurred with both the retrograde single and double balloon techniques. Three deaths occurred; two during the antegrade technique and one after the retrograde double balloon technique. Thus, balloon aortic valvuloplasty can be effectively performed using any of the three techniques. However, the differing techniques have inherent advantages in specific situations, as well as potential complications.

Aged↗
PubMed1989

Balloon mitral valvuloplasty via retrograde left atrial catheterization.

A technique for performing retrograde catheterization of the left atrium followed by double balloon mitral valvuloplasty without transseptal catheterization is described. Three patients have undergone double balloon mitral valvuloplasty by means of this technique, all with marked improvement in postdilatation mitral valve areas. The technique avoids iatrogenic atrial septal defects and is less difficult to perform than transseptal catheterization.

Adult↗
PubMed1989

Serum thyroxine change and clinical recovery in psychiatric inpatients.

Serum free thyroxine (FT4), total thyroxine (TT4), and Brief Psychiatric Rating Scale (BPRS) measurements were obtained following hospital admission and at 2-week intervals during hospitalization in 80 male psychiatric inpatients with a variety of major psychotic and affective disorders. A strong correlation between the range values for BPRS sum and for FT4 (p less than 0.005) and TT4 (p less than 0.001) levels indicated that change in overall symptom severity was linked to change in thyroxine levels during clinical recovery. We found the relationship not to be a simple one, but to require definition of criteria for three patient subgroups for each hormone, taking into account the initial absolute thyroxine level, as well as the direction and magnitude of hormonal change during recovery. The hormonally defined "good recovery" subgroup included patients with high initial thyroxine levels that then fell substantially, patients with low initial thyroxine levels that then rose substantially, and patients with initial thyroxine levels in the middle range that subsequently changed substantially. The hormonally defined "poor recovery" subgroup included those patients not meeting these criteria. The degree of clinical improvement in the hormonally defined good recovery group was significantly greater by almost twofold than the poor recovery group both for FT4 (p less than 0.04) and TT4 (p less than 0.02). These findings suggest that a "normalizing" principle underlies the relationship between clinical recovery and thyroxine levels and that both FT4 and TT4 levels within the normal range appear to have clinical significance in either reflecting or contributing to the course of a variety of psychiatric disorders and possibly having a role in pathogenesis.

Adolescent↗
PubMed1989

Serum thyroxine levels in schizophrenic and affective disorder diagnostic subgroups.

Serum free thyroxine (FT4) and total thyroxine (TT4) levels were measured at 2-week intervals during the course of hospitalization in 29 male inpatients in the following four diagnostic groups: paranoid schizophrenia (PS); undifferentiated schizophrenia; bipolar I disorder, manic; and major depressive disorder, endogenous type. The most striking finding was a difference in the direction of both TT4 and FT4 change during clinical recovery in the PS group compared with the other three groups. Analysis of the delta values, representing the change between admission and discharge values, revealed significant differences between the mean rise in the PS group vs. the mean decreases in the other three groups for both TT4 (p less than .0003) and FT4 (p less than .003). For TT4, 75% of the PS group showed a rise during recovery in contrast to 4% of the remaining groups; for FT4, 50% of the PS group showed a rise compared with 14% of the other groups. A significant difference was also observed between the FT4 levels of bipolar I, manic vs. PS patients at the time of hospital admission, which may have potential usefulness in the differential diagnosis of these two disorders. This study emphasizes the importance of exploring more fully the psychiatric significance of thyroxine levels within the endocrinological normal range and of doing longitudinal assessments of thyroxine and symptom changes during clinical recovery in psychiatric disorders.

Adult↗