Surgical ventricular reconstruction and subendocardial resection for the treatment of refractory ventricular tachycardia

We describe a case of 64-year-old female patient with ventricular tachycardia intractable to medical treatment and acute heart failure following myocardial infarction. Emergency surgical ventricular reconstruction and subendocardial resection was undertaken. We discuss the option of surgical intervention in this difficult and unusual clinical scenario.     

Effect of beta-adrenergic blockade on hormonal responses during continuous and intermittent exercise

Summary The modifying effect on exercise performance and neuroendocrine response of the nonselective beta blocker timolol (10 mg b.i.d. for 5 days) and the beta₁-selective beta blocker metoprolol (100 mg b.i.d. for 5 days) was studied. The hormones studied were growth hormone, prolactin, cortisol, renin, epinephrine, dopamine, and norepinephrine. The response was studied during short-term maximal dynamic exercise, using two different exercise protocols; continuous (n=11) and intermittent (n=9) bicycle ergometry, in normal healthy young men. Accumulated work on placebo was nearly identical in the two studies, but was significantly reduced by 10.4% and 6.6% with timolol and by 4.7% and 6.7% with metoprolol, during continuous and intermittent exercise, respectively. During continuous exercise, accumulated work was 5.8% lower (p<0.05) with timolol than with metoprolol. The hormonal plasma concentrations of all hormones except renin were higher during continuous exercise than during intermittent exercise. Beta blockade had no effect on baseline hormonal levels, but the response was markedly changed during exercise. Maximum epinephrine, cortisol, and prolactin responses increased after beta blockade; dopamine remained nearly unchanged; while the renin responses were attenuated. Norepinephrine concentrations were slightly increased during continuous exercise by beta blockade and rose in direct proportion to the increase in workload. During intermittent exercise, maximum norepinephrine levels were significantly reduced by beta blockade compared with placebo. Thus the effect of beta₁-selective and nonselective beta receptor blockade on circulating hormones does not seem to explain the reduced exercise capacity following beta blockade.     

Differential coupling of CC chemokine receptors to multiple heterotrimeric G proteins in human interleukin-2-activated natural killer cells

Using two different approaches, we have investigated the types of G proteins coupled to CC chemokine receptors. First, permeabilization of interleukin-2-activated natural killer (IANK) cells with streptolysin-O and introduction of anti-G protein antibodies inside these cells resulted in the following. (1) Anti-G(s), anti-G(o), and anti-G(z) inhibited the migration of IANK cells in response to macrophage- inflammatory protein-1 alpha (MIP-1 alpha), monocyte chemoattractant protein-1 (MCP-1), or regulated on activation normal T cell expressed and secreted (RANTES). (2) Anti-Gi inhibited their migration in response to MCP-1 or RANTES but not in response to MIP-1 alpha. Second, incubation of IANK cell membranes with anti-G protein antibodies before incubating with (gamma-35S) GTP or (gamma-32P) GTP, resulted in the following. (1) Anti-G(s), anti-G(o), or anti-G(z) inhibited GTP binding and GTPase activity in the presence of MIP-1 alpha, or RANTES. (2) Anti- G(i) inhibited GTP binding and GTPase activity in the presence of MCP-1 or RANTES but not in the presence of MIP-1 alpha. The inhibitory effect of anti-G protein antibodies was reversed upon incubating these antibodies with their respective synthetic peptides before addition to IANK cell membranes. These results suggest that MCP-1 and RANTES receptors are promiscuously coupled to multiple G proteins in IANK cell membranes and that this coupling is different from MIP-1 alpha receptors, which seem to be coupled to G(s), G(o), and G(z) but not to G(i).     

Malignant appendiceal carcinoid with intussusception of the base manifesting as a cecal tumor: Report of a case

Summary A case of an appendiceal carcinoid tumor with regional lymph-node metastases is presented. The size of the tumor was remarkable, as the appendix was infiltrated throughout its length. The proximal part of the appendix was intussuscepted into the cecum. Preoperatively, the lesion was diagnosed as a polypoid tumor of the cecum. A primary right hemicolectomy was carried out. Read at the Annual meeting of the Norwegian Surgical Association, Oslo, October 21 to 23, 1976.     

Effect of sodium depletion on plasma renin concentration before and during adrenergic beta-receptor blockade with propranolol in normotensive man.

Plasma renin levels have been used to discriminate between different forms of hypertension, but how to define the normal range of plasma renin levels has not been agreed upon. Sodium depletion stimulates renin release. Evaluation of plasma renin would, therefore seem possible only in relation to sodium balance. Plasma renin concentration and concurrent daily sodium excretion were determined in 33 healthy normotensive subjects (control group) ingesting high, normal and low sodium diets. A well-defined hyperbolic relationship was found between the two variables indicating that the physiologic level of plasma renin concentration depends on the state of sodium balance. An increase in plasma potassium concentration may reduce plasma renin concentration, but this appeared to be overruled by the stimulating effect of sodium depletion. To examine whether beta-adrenergic stimulation contributes to the increase in plasma renin concentration during sodium depletion, the relationship between plasma renin concentration and concurrent sodium excretion was studied during beta-receptor blockade with propranolol. In 20 healthy normotensive subjects in whom beta-receptor blockade was verified by a significant reduction in pulse rate, the same hyperbolic relationship was found between plasma renin concentration and sodium excretion as in the control group showing that sodium depletion stimulates renin release independent of sympathetic nervous activity.     

Clinical features and outcome in childhood T-cell leukemia-lymphoma according to stage of thymocyte differentiation: a Pediatric Oncology Group Study

The immunophenotypes of lymphoblasts from children with newly diagnosed T-cell acute lymphoid leukemia (T-ALL, n = 101) or T-cell non-Hodgkin lymphoma (T-NHL, n = 31) were analyzed to correlate stage of thymocyte differentiation with clinical features and outcome. The 67 boys and 34 girls with T-ALL were 1 month to 18 years old (median, 8 years) with leukocyte counts ranging from 2 to 810 x 10(9)/L (median, 55 x 10(9)/L). Eighteen of these patients were black, and 70 had a mediastinal mass. Twenty-six boys and five girls with a median age of 9 years (range, 1 to 20 years) had T-NHL. Seven of these patients were black, and 24 had a mediastinal mass. The distributions of thymocyte developmental stages (early [CD7+], intermediate [CD1+ and/or CD4+ and/or CD8+], and mature [CD3+]) in cases of T-ALL and T-NHL were significantly different: 34%, 43%, and 23% v 6%, 62%, and 32% (P = .02). A comparison of the patients' clinical features according to the maturational stage of thymocytes failed to disclose significant differences in the majority of characteristics studied. However, patients with mature-stage T-NHL, with or without the addition of subjects with mature-stage T-ALL, were less likely to have a mediastinal mass (P = .02 for both comparisons). Those with intermediate-stage T-cell malignancy (T-ALL and T-NHL combined) were the subgroup most likely to have a mediastinal mass (P = .01). Response to remission induction therapy was significantly worse in the T-ALL subgroup with an early-stage phenotype: a failure rate of 21% v 0% and 6% for the two more differentiated phenotypic subgroups (P = .007). Event-free survival was not affected by thymocyte maturational stage in cases of either T-ALL or T-NHL. Despite evidence of clinical heterogeneity among the maturational stages of T-cell malignancies in children, these developmental subdivisions do not appear to be critical determinants of outcome once remission is achieved. We conclude that such phenotypes need not be included in the stratification plans for clinical trials using common induction treatment.     

Lysyl oxidase-like protein 2 (LOXL2) modulates barrier function in cholangiocytes in cholestasis

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