Corynebacterium diphtheriae endocarditis in an adult with congenital heart disease: a case report

A rare case of septicaemia and endocarditis due to Corynebacterium diphtheriae is presented. The patient had underlying congenital heart disease and died despite high-dose penicillin therapy. The implications for diagnosis and identification and some public health issues brought to the fore by the case are discussed.

Supraventricular tachycardia, right atrial pressure, atrial natriuretic peptide and polyuria--a necessary sequence?

The release of atrial natriuretic peptide (ANP) may be stimulated by tachycardia and the evidence from human studies suggests that this is mediated by a rise in atrial pressure. However, animal experiments suggest that tachycardia can by itself increase ANP levels without increasing right atrial pressure (RAP). We report here the case of a healthy volunteer who had supraventricular tachycardia (SVT) whilst participating in a study evaluating the relationship between changes in RAP and changes in ANP. The ANP levels rose following the SVT but there was no rise in RAP, suggesting that heart rate can modulate ANP levels without changes in RAP as has been shown in animal experiments.

Selection of dental procedures for antibiotic prophylaxis against infective endocarditis

A dental source of infection remains the most common identifiable risk factor in infective endocarditis and this may be particularly important in patients at 'high risk'. We therefore performed a questionnaire survey of dental practitioners to assess acceptance of The British Society of Antimicrobial Chemotherapy (BSAC) recommendations, especially with regards to selection of dental procedures for antibiotic prophylaxis. The results showed that the dental practitioners surveyed treated the 'high risk' patient group differently by extending the range of dental procedures covered by antibiotics but the BSAC only recommend that they be treated differently by hospital treatment and/or parenteral antibiotics. This must be an area of concern and deserves further attention, especially with regards to the need for wider publicity and the range of dental procedures that should be covered in the 'high risk' group where morbidity and mortality from infective endocarditis are higher.

Effects of calcium-modifying agents on integrity of rabbit isolated gastric mucosal cells

The effects of Ca(2+)-modifying agents on the disruption of gastric isolated mucosal cells from the rabbit have been examined. Fundic mucosal cells were isolated and enriched by centrifugal elutriation, with cellular viability and disruption being assessed by trypan blue dye exclusion and by the release of lysosomal enzymes. The Ca2+ ionophore A23187 (3.125-50 microM) induced a concentration-dependent increase in enzyme marker release and decreased dye exclusion from the cells. Ionophore-induced enzyme release was reduced by removal of Ca2+ or by incubation with EDTA. Cells from the medium-sized fraction were found to be more sensitive to damage by A23187 than were larger-diameter cells. Enzyme release from these cells was also induced by the Ca(2+)-channel activator BAY K 8644 (1.5 microM). The Ca(2+)-channel antagonists, nifedipine, verapamil, and diltiazem (1 microM), abolished enzyme release in response to BAY K 8644 (1.5 microM) but did not affect A23187 (25 microM)-induced responses. Ethanol (5 and 8%) also induced a concentration-dependent increase in enzyme release and decrease in dye exclusion, but this effect was not dependent on the external Ca2+ concentration. However, threshold concentrations of A23187 (1.56 microM) substantially potentiated the cell damage induced by ethanol (5 or 8%), and this synergism was dependent on external Ca2+. These data suggest that agents that produce an inappropriate Ca2+ flux can disrupt or augment disruption of gastric mucosal cells and thus Ca2+ homeostasis is essential for maintenance of mucosal cell integrity.

Efficacy of a self-directed behavioral health change program: weight, body composition, cardiovascular fitness, blood pressure, health risk, and psychosocial mediating variables

This study assessed the efficacy of a comprehensive behavioral health program designed to promote self-initiated change in overweight healthy middle-aged adults (M = 49 years). Three treatment groups (total n = 25) differing in type of social support provided (i.e., group plus professional versus group plus peer versus group only) received 13 treatment sessions and 6 maintenance sessions scheduled over a full year. A self-directed change intervention taught several cognitive-behavioral techniques as they applied to exercise adherence, weight reduction/maintenance, and stress management. Combined treatment groups (n = 25) improved significantly more than an assessment only control group (n = 9) in weight, percentage body fat, cardiovascular fitness, exercise adherence, health-risk appraisal, chronic tension (MBHI, scale A), and systolic and diastolic blood pressure at both post-treatment and 6-month follow-up assessments. Self-motivation, group treatment attendance, and health-risk appraisal significantly related (r's = .30-.56) to several posttreatment and follow-up measures of behavioral health change. No significant differences were found among the three treatment groups on any of the outcome measures.

Sepulveda Epilepsy Education: the efficacy of a psychoeducational treatment program in treating medical and psychosocial aspects of epilepsy

The present study evaluated the efficacy of the Sepulveda Epilepsy Education program (SEE), using a controlled outcome design. SEE is a 2-day psychoeducational treatment program designed to provide medical education and psychosocial therapy. Thirty-eight outpatients, matched according to seizure type and frequency, were randomly assigned to treatment (n = 20) or waiting-list control (n = 18) groups. The major outcome measures used were a 50-item true-false test specifically designed to evaluate the SEE program, the Washington Psychosocial Seizure Inventory, the Beck Depression Inventory, Lubin's Depression Adjective Checklist, the State-Trait Anxiety Inventory, the Acceptance of Disability Scale, and Sherer's Self-Efficacy Scale. Significant differences between the two groups were found on the three major subscales of the 50-item true-false test. The treatment group demonstrated a significant increase in overall understanding of epilepsy, a significant decrease in fear of seizures, and a significant decrease in hazardous medical self-management practices. In addition, an objective measure of blood levels of antiepileptic drugs (AEDs) showed the treatment group to have a significant increase in medication compliance.

Pathohistogenetic approach on the etiology of Yunnan tin miner's lung cancer

Pathological observation was made in 100 surgically resected lung cancers of Yunnan tin miners: peripheral type 44 including 9 scar cancers; central type 56, 27 of whom were early lung cancer, with limited initial loci in a well defined area. On the basis of dust retention in original sites of lung cancer and results of X-ray microanalysis, a scheme for calculating the relative probability of causation is formulated. The result of calculation shows that the contribution of exposure to radon daughters is about 7 times that of ore dust retention in the etiology of Yunnan tin miner's lung cancer.

Cognitive-behavior therapy with adult patients with epilepsy: a controlled outcome study

The present study evaluated the efficacy of group cognitive-behavior therapy for the alleviation of psychosocial problems and reduction of seizures with adult epileptic patients. Twenty-seven outpatients were randomly assigned to one of three groups: Cognitive-Behavior Therapy, Supportive Counseling (attention-placebo control), and Waiting list (no treatment control). The major outcome measures used were: patient's, neurologist's, and therapist's global ratings of psychological adjustment, patient's target complaints and weekly seizure frequency, patient's and neurologist's ratings of seizure control, the Minnesota Multiphasic Personality Inventory, the Washington Psychosocial Seizure Inventory, and the Beck Depression Inventory. No significant differences were found among the three groups on these measures except for therapist's global ratings of psychological adjustment, on which both the Cognitive-Behavior Therapy and Supportive Counseling groups improved significantly after therapy, but the Waiting List control group did not. Overall, little support was found for the efficacy of group cognitive behavior therapy (eight 2-h weekly sessions) for the reduction of psychosocial difficulties or seizures. Implications of the present findings are discussed, with the need for further controlled outcome research stressed.

Psychosocial functioning of adult epileptic and MS patients and adult normal controls on the WPSI

The psychosocial functioning of adult epileptic outpatients (N = 68) as assessed by the Washington Psychosocial Seizure Inventory (WPSI) was compared to that of control groups of adult MS outpatients (N = 37) and normal subjects (N = 42). When all WPSI profiles were considered, the epilepsy group showed distinct difficulties in Emotional Adjustment and Adjustment to Seizures, whereas the MS group had difficulties only in Emotional Adjustment. However, the MS group had significantly higher Lie Scale scores than did normal subjects. The epilepsy group had significantly more emotional problems than normal subjects and significantly more problems adjusting to their disorder than did the MS group. However, when only valid WPSI profiles were considered, the only significant finding was that the epilepsy group (N = 44) and the MS group (N = 20) had more emotional problems than normal subjects (N = 35). The epilepsy group showed distinct difficulties in Emotional Adjustment and Adjustment to Seizures, whereas the MS group had difficulties in Emotional Adjustment, Interpersonal Adjustment, and Overall Psychosocial Functioning. Implications are discussed.

Psychosocial problems in adults with epilepsy: comparison of findings from four countries

Psychosocial problems in groups of adults with epilepsy from Canada, Finland, the German Democratic Republic, and the United States were evaluated by the Washington Psychosocial Seizure Inventory. A number of similarities in psychosocial concerns were found across the four countries. At the forefront for each group were emotional problems, followed by concerns pertaining to adjustment to the seizures themselves. Where far-reaching governmental support of a financial and vocational nature was lacking, difficulties in these areas were also noted. In all cases, few problems were found in matters pertaining to family relationships and to medical care. Hypotheses to account for differences between the groups were discussed.

Active and inactive renin in low renin states: studies in human plasma

Low PRA and active renin (AR) may be accompanied by low inactive renin (IR), indicating impaired renin production, or by normal or elevated IR, suggesting defective conversion to AR. To explore these possibilities, plasma AR and IR (acid activation method) were measured in normal volunteers and in patients with low PRA. All low renin states showed significant low PRA and AR when compared to normals; on the other hand, IR was 11.8 +/- 1.1 ng/ml.h in normals; low in primary aldosteronism (2.1 +/- 0.5 ng/ml.h) and anephric subjects; normal in low renin essential hypertension (7.5 +/- 1.3 ng/ml.h), nondiabetic hyporeninemic hypoaldosteronism (9.4 +/- 1.6 ng/ml.h) and diabetic hyporeninemic hypoaldosteronism (17.3 +/- 2.5 ng/ml.h); and significantly elevated in diabetics with nephropathy (21.0 +/- 1.6 ng/ml.h). The acute iv infusion of 2 liters saline in normal subjects did not decrease IR (11.8 +/- 2.0 vs. 13.0 +/- 1.8 ng/ml.h) despite a reduction in PRA and AR of 50-75%. These data indicate that in cases of primary aldosteronism and in anephric subjects both AR and IR are decreased, suggesting a decrease in total renal synthesis or release, whereas in low renin essential hypertension, nondiabetic hyporeninemic hypoaldosteronism, diabetic hyporeninemic aldosteronism, and diabetics with nephropathy AR is low and IR is normal or high, suggesting the possibility of impaired conversion to AR.

The effect of biofeedback-assisted relaxation training on blood pressure and selected biochemical parameters in patients with essential hypertension

The effect of EMG biofeedback-assisted relaxation on blood pressure and selected biochemical parameters was evaluated in 38 patients with essential hypertension. Training consisted of 8 weeks of biofeedback and home practice of relaxation exercises. Mean blood pressure decreased in the experimental group from 144/90 to 133/84 mm Hg while the control group remained unchanged. Statistically significant decreases in the experimental group also occurred in muscle tension levels, in plasma aldosterone, and in urinary cortisol. Both aldosterone and cortisol are secreted by the adrenal cortex. It was concluded that the technique taught to the experimental group produced a reduction in skeletal muscle tension and a decrease in stress responding mediated by the adrenal cortex.

Cortisol production by testicular tumors in a patient with congenital adrenal hyperplasia (21-hydroxylase deficiency)

Bilateral testicular tumors are known to occur in congenital adrenal hyperplasia, but their steroidogenic properties are not well studied. We have recently demonstrated steroid 11 beta-hydroxylase activity in these tumors from a 27-yr-old patient with documented salt-losing congenital hyperplasia (21-hydroxylase deficiency). Spermatic venous blood obtained at operation contained 3.6-5 ng/ml cortisol, as measured by specific RIA after Sephadex LH-20 chromatography. In contrast, the peripheral venous cortisol level was 0.64 ng/ml. The presence of 11 beta-hydroxylase activity was demonstrated by the in vitro conversion of [3H]deoxycorticosterone to [3H]corticosterone in tumor tissue. The conversion ratio of deoxycorticosterone to corticosterone was 4.3% and 7.07%/mg tissue in the tumor tissue, whereas in normal testicular tissue, it was less than 1%. The radiochemical identity of corticosterone was confirmed by rechromatography on Sephadex LH-20, coelution with added [14C]corticosterone, and a constant 3H to 14C ratio after acetylation and thin layer chromatography. The tumor cells grown in primary culture produced steroids and responded to ACTH and hCG. Electron microscopy of the tumor revealed a large number of mitochondria containing electron dense granules. Light microscopy was compatible with Leydig cell tumor. In conclusion, testicular tumors in association with congenital adrenal hyperplasia have morphological features of Leydig cells but have the capability of 11 beta-hydroxylation and cortisol production, properties which are unique to adrenocortical tissue. These findings suggest that they originate from pluripotential cells in the testicles. Regression of these tumors has been reported with optimal biochemical control of the disease.

Direct action of kallikrein and other proteases on the renin-angiotensin system

Kallikrein is present in the renal tubule near the macula densa, and it has recently been shown to activate inactive renin in human plasma. We recently showed that kallikrein was a potent stimulus of renin release and increased renin secretion in a dose-dependent fashion. To study its effect on renal renin release, we superfused rat renal cortical slices with purified rat urinary kallikrein. Kallikrein-stimulated renin release was completely abolished by trasylol and by amiloride, but was not affected by soybean trypsin inhibitor. Indomethacin did not block kallikrein action, indicating that kallikrein's effect is not mediated via kinin generation and prostaglandins. Kallikrein-stimulated renin release was not blocked by propranolol, trasylol did not block isoproterenol, and dibutyryl cyclic AMP stimulated renin release, indicating that kallikrein may not play a role in the beta-adrenergic mechanism of renin release. There was no demonstrable acid-activatable or kallikrein activatable renin in the superfusate, suggesting that all of the renin release was in the active form. Cathepsin D and plasmin also stimulated renin release from kidney slices in pH 6.0 buffer, whereas trypsin and pepsin did not. Our results support the hypothesis that kallikrein may play a role in the secretion of renin by the kidney. Other proteases can also release renin from the kidney.

Effects of indomethacin on plasma renin activity in the conscious rat

The role of prostaglandins in the control of renin release in vivo was evaluated in the conscious rat. Indomethacin suppressed urinary prostaglandin E2 (PGE2) excretion from 5.3 +/- 0.5 to 2.6 +/- 0.5 ng/3 h (P less than 0.001). Basal plasma renin activity (PRA) fell from 6.20 +/- 1.07 to 2.98 +/- 0.45 ng . ml-1 . h-1 (P less than 0.02). Indomethacin suppressed PRA stimulated by furosemide, insulin-induced hypoglycemia, hydralazine, isoproterenol, arachidonic acid, and sodium-free diet, whereas PRA stimulated by PGE2 was not suppressed by indomethacin. The suppression of PRA by indomethacin in the sodium-deplete state rules out sodium retention as the mechanism of action of indomethacin. These results indicate that inhibition of prostaglandin synthesis by indomethacin partially blocks the renin response to several of the known stimulators, suggesting that prostaglandins may play a pivotal role in the control of renin release.

Hyporeninemic hypoaldosteronism. An overlooked cause of hyperkalemia

To establish the frequency and clinical and biochemical characteristics of hyporeninemic hypoaldosteronism (HH), we reviewed 100 consecutive cases of hyperkalemia (potassium content > 5.3 mEq/L). The most common cause was end-stage renal failure (34%). Other causes included overzealous potassium replacement, spironolactone therapy, hemolysis, acute renal failure, acidosis, thrombocytosis, and Addison's disease. Ten of 19 patients with unexplained hyperkalemia showed suppressed renin (0.12 to 1.3 ng/mL/hr) and aldosterone (5.4 to 21.6 ng/dL) responses to furosemide-posture challenge. Cortisol reserve was normal in HH. Fludrocortisone acetate therapy corrected the hyperkalemia. Other features of HH include low serum bicarbonate content, mild renal insufficiency, diabetes, and advanced age. The use of indomethacin and ibuprofen was associated with one case of HH each. Results suggest that HH is an overlooked cause of hyperkalemia, especially in patients whose hyperkalemia is unexplained.

Inactive renin and prostaglandin E2 production in hyporeninemic hypoaldosteronism

To ascertain whether inactive renin (IR) might predominate in the syndrome of hyporeninemic hypoaldosteronism (HH) and whether the production of prostaglandin E2 (PGE2), a potent stimulus for renin release, might be decreased, we measured PRA, active renin (AR), and IR by the acid activation method and urinary PGE2 in 10 patients with HH. In contrast to uniformly low levels of PRA (0.6 +/- 0.2 ng/ml . h) and AR (2.7 +/- 0.6), IR was either normal or elevated (14.7 +/- 2.2 in HH; 11.8 +/- 1.1 in 28 normal subjects) and the IR to AR ratio was markedly increased (8.5 +/- 2.0 vs. 3.4 +/- 0.5; P < 0.05). Urinary PGE2 was decreased in 4 patients but was in the normal range in 5 other patients with HH. In 16 human volunteers, PG inhibition with indomethacin led to a significant decrease in AR (P < 0.05) but not in IR, and the IR to AR ratio increased 2-fold (P < 0.02). The data suggest that HH is a disease involving the defective conversion of IR to AR rather than impaired total renin production. In some patients, PG deficiency may contribute to the development of HH.