The relationship between cardiovascular reactivity and heartbeat detection

This experiment tested the hypothesis that inotropic cardiovascular reactivity to stress is related to performance on heartbeat discrimination tasks. The experiment also compared the efficacy of a specific modification of two popular heartbeat discrimination paradigms, Whitehead's and Katkin's. Subjects were 48 male undergraduates who performed both discrimination tasks and then were subjected to mental arithmetic stress. Results indicated that high cardiovascular reactors were better detectors than low reactors. Results also indicated that subjects performed better on the modified Whitehead task than on the modified Katkin task.     

Successful Treatment of a Stenosed Modified Blalock-Taussig Shunt Using a Palmaz-Schatz Stent: A Case Report

Case report of a 15-year-old white male with complex cyanotic heart disease and multiple cardiac surgery including bilateral modified Blalock-Taussig shunt. The patient developed worsening cyanosis and exercise intolerance for the last several months. He underwent percutaneous balloon angioplasty and placement of a PS 204 Palmaz-Schatz balloon expandable stent for correction of severe stenosis at the junction of the right subclavian artery and a 6-mm interposition Gore-Tex graft. Since he was not a candidate for definitive surgery, this palliative procedure was performed to avoid repeat thoracotomy and to provide long-term relief of the stenosis. Stent placement in children can be challenging due to vascular access and complex anatomy. We suggest long-term follow-up to validate the success of this procedure.     

A comparison of vincristine and doxorubicin infusional chemotherapy with methylprednisolone (VAMP) with the addition of weekly cyclophosphamide (C-VAMP) as induction treatment followed by autografting in previously untreated myeloma

In a sequential nonrandomized study, 204 consecutive unselected patients aged < 70 years received induction chemotherapy with infusional vincristine and adriamycin with oral methyl prednisolone (VAMP; n =75) or with additional cyclophosphamide, C-VAMP ( n =129). 38/129 C-VAMP patients also received verapamil during induction as part of a controlled trial with the aim to overcome drug resistance. A median of five courses (range 1–11) of chemotherapy were required before maximal response was attained and this was similar in both groups. An over-all response rate of 71% was noted at the end of induction. The complete remission (CR) rate with C-VAMP was 24%, which was significantly higher ( P =0.04) than the CR rate with VAMP alone (8%). The addition of verapamil did not alter the response rate of C-VAMP. Compliance to VAMP was overall 83% and not affected by the addition of cyclophosphamide. The proportion of patients going on to receive high-dose chemotherapy and an autograft was the same for VAMP and C-VAMP treated patients (71%). The median overall survival (OS) and progression-free survival (PFS) for the whole group were 4.4 years and 2.0 years and no difference in outcome was observed between the different treatment groups. Therefore the addition of weekly cyclophosphamide to VAMP induction therapy has significantly improved the response rates of previously untreated myeloma patients. C-VAMP was not more toxic and did not compromise the chances of receiving an autograft. Verapamil was without influence on any parameters in this study.     

A technique for the culture of Barrett's oesophageal cells

Establishment of cells in tissue culture from Barrett's columnar epithelium has been difficult. The aim of this study was to develop a successful tissue culture method employing a serumfree medium for cultivation of Barrett's epithelial cells. Fragments of Barrett's mucosal tissue were explanted in a 3:1 mixture of Dulbecco's modification of Eagle's medium and Ham's F12, to initiate the outgrowth of epithelial cells. Subsequently, a commercial serum-free medium (formulated for the growth of keratinocytes) was used for the propagation of Barrett's oesophagus cells without fibroblast growth. Cells established in culture retained their epithelial morphology, stained positive for cytokeratin, and contained Alcian blue (pH 2.5) and periodic acid-Schiff reagent-positive/diastase-resistant vacuoles, confirming their origin from Barrett's epithelium. Electron microscopy showed tonofilaments, microvilli and desmosomes. Coating the surface of culture vessels was not required and four cell strains could be passaged up to 20 times with no fibroblast growth, in the keratinocyte serumfree medium.     

Erythrodermic Juvenile Dermatomyositis

Abstract:   Juvenile dermatomyositis (JDMS) is an inflammatory myopathy with various cutaneous manifestations, usually affecting children between 2 and 15 years of age. We describe a 9-year-old female diagnosed with Juvenile dermatomyositis presenting with generalized erythroderma, Gottron papules, inflammatory myopathy associated with systemic hypertension confirmed on histopathogical examination of skin and muscle biopsy. Since erythroderma, though rare, is an early manifestation of dermatomyositis (adult onset), presence in a pediatric case should prompt early investigations and effective management by a multispeciality team.     

Comparative Left Ventricular Function Following Atrial, Septal, and Apical Single Chamber Heart Pacing in the Young

Ventricular pacing, typically initiated from a RV apical electrode, inherently causes abnormal biventricular activation, decreases LV function, and causes histopathological changes. Since pacing initiated in childhood can he expected to have a more protracted course compared with the adult, the consequences of this alteration in LV hemodynamics gain added significance among the young pacemaker recipient. The purpose of this study was to evaluate the potential of improving paced LV function by a septal electrode implant site. Acute alterations in cardiac index, LV pressure, and contraction indices, including dP/dt, Vmax. and Vpm, were compared among 22 patients (median age 10 years) with normal cardiac anatomy during intracardiac electrophysiological studies. LV hemodynamics were measured during intrinsic rhythms and following 15 minutes of atrial, HV apical, and septal pacing at an appropriate exercise rate for age of 150 ppm. Results showed a significant decrease in LV dP/dt, Vmax, and Vpm, and increase in LV end-diastolic pressure only with apical pacing. Septal pacing, in spite of loss of any atrial contribution to ventricular filling, maintained comparable indices with intrinsic and atrial paced rhythms. This study demonstrates that normalized LV function is maintained by septal and deteriorates with apical pacing acutely among young, nonischemic hearts. Continued evaluation of appropriate pacing electrode designs to permit septal implant is needed to ensure optimal chronically paced LV function.