Auditory and visual semantic priming using different stimulus onset asynchronies: An event-related brain potential study

Semantic priming effects (behavioral and electrophysiological) were compared in the visual and auditory modalities across three stimulus onset asynchronies (SOAs; 0, 200, and 800 ms). When both prime and target were presented in the visual modality (the prime just to the left of a fixation point and the target to the right) there were N400 priming effects present across the three SOAs. However, the N400 in the 0-ms SOA condition extended longer in time (800 vs. 500 ms) than in the other SOAs. When both the prime and target were presented in the auditory modality (the prime to the right ear and the target to the left), the largest priming effects were found for the 800-ms SOA. Moreover, there was a relatively early priming effect present in the 0- and 800-ms SOA conditions but not in the 200-ms condition. The results are discussed in terms of modality differences in the time course of word comprehension processes.     

Experimental Assessment of Right Ventricular Function in Normal Pigs with a Left Ventricular Assist Device

Abstract: Right ventricular (RV) failure during the use of a left ventricular assist device (LVAD) is the leading cause of death in circulatory support patients. Previous work, both experimentally and clinically, has shown the difficulties in predicting the behavior of the right ventricle at the start of LVAD. An experimental study has been designed to evaluate RV functional changes during LVAD and its relation to preload changes. The model used adult mongrel pigs (n = 10). Right ventricular functional parameters were measured with a thermodilution RV ejection fraction catheter. The left ventricle was supported by a Nippon Zeon blood pump. Two groups were studied, the first one was the LVAD–off group (n = 5) and the other was the LVAD–on group (n = 5) which was supported by LVAD at maximum flow. Change of cardiac output, mean pulmonary artery pressure (PAP), RV stroke work, and RV ejection fraction in both groups were not significantly different. However, the relationship between right ventricular end–diastolic pressure (RV–EDP) and right ventricular stroke volume (RVSV) was significantly changed at a high level of RV–EDP. When RV–EDP was over 6. 5 mm Hg in the LVAD–off group, RVSV decreased to 52. 3 ± 11. 5 ml while in the LVAD–on group, RVSV increased to 97. 2 ± 22. 0 ml. The change in PAP in the LVAD–on group was lower than in the LVAD–off group. We conclude that, at the volume overload state, LVAD can reduce the afterload of the right ventricle and maintain Frank–Starling's effect, thus having a beneficial effect on right ventricular performance.     

Overview of Developmental Heart Defects by Dioxins,PCBs, and Pesticides

The developing cardiovascular system is a sensitive target of many environmental pollutants, including dioxins, dioxin-like polychlorinated biphenyls (PCBs), and some pesticides such as methyl parathion. Laboratory research has utilized a variety of vertebrate models to elucidate potential mechanisms that mediate this cardioteratogenicity and to establish the sensitivity of different species for predicting potential risk to environmental and human health. Studies of dioxin and dioxin-like PCBs have illustrated that piscine, avian, and mammalian embryos exhibit cardiovascular structural changes and functional deficits, although the specific characteristics vary among the individual models. Piscine models typically exhibit reduced blood flow, altered heart looping, and reduced heart size and contraction rate. The chick embryo exhibits extensive cardiac dilation, thinner ventricle walls, and reduced responsiveness to chronotropic stimuli, while the murine embryo exhibits reduced heart size. It is notable that in all models the dioxin-associated cardioteratogenicity is associated with increases in cardiovascular apoptosis and decreases in cardiocyte proliferation. While the cardiotertogenicity in piscine and avian species is associated with overt morbidity and mortality, that is not the case for the murine embryo. However, murine offspring exposed during development to dioxin exhibit cardiac hypertrophy and an increased sensitivity to a second cardiovascular insult in adulthood. Thus, although the mammalian embryo is less sensitive to cardiovascular defects by dioxin and dioxin-like compounds, developmental exposure increases the risk of cardiovascular disease later in life. The impact of developmental exposure to dioxin-like chemicals on human cardiovascular disease susceptibility is not known. However, recent animal research has confirmed human epidemiology studies that dioxin exposure in adulthood is associated with hypertension and cardiovascular disease.     

The Spectrum of Angiographic Findings in Transitional Cell Carcinoma of the Kidney

The spectrum of angiographic finding in 20 patients with transitional cell carcinomas of the kidney is described. In 15 of 20 patients (75%), prospective diagnosis of transitional cell carcinomas were made because of a combination of the angiographic findings; tumour vessels, tumour stain, prominent pelviureteric arteries and arterial encasement. In 4 patients with negative angiograms the lesions were relatively small in size and were situated within the renal parenchyma, primarily involving the calyces. The use of pharmacoangiographic agents such as epine-phrine and priscoline improved the angiographic visualization of transitional cell carcinomas of the kidney. For the past several years angiography has had a central role in the evaluation of patients with hematuria and renal masses¹. 5,6,7,8. Although the use of diagnostic ultrasound and renal puncture have eliminated angiography from the diagnosis of renal cysts, most renal masses which are solid or which have equivocal findings at ultrasound still undergo angiography. At the same time, the decreasing use of retrograde urography has resulted in more frequent angiography in patients with unilateral nonfunctioning kidneys. Transitional cell carcinomas of the renal pelvis are an important cause of both hematuria and non-functioning kidneys. We have therefore reviewed our material to reassess the angiographic abnormalities caused by the transitional cell carcinomas and the overall accuracy of the angiography in the diagnosis of these lesions.     

Ventricular tachycardia in a neonate secondary to hyperkalaemia

ABSTRACT. We report a preterm infant with ventricular arrhythmias secondary to hyperkalaemia in the first 48 hours of life. The arrhythmias were life threatening and required pharmacological and electrical cardioversion. Aspects of neonatal hyperkalaemia and related arrhythmias are discussed.     

Five-Month Oral (Diet) Toxicity/lnfectivity Study of Bacillus thuringiensis Insecticides in Sheep

Five-Month Oral (Diet) Toxicity/Infectivity Study of Bacillusthuringiensis Insecticides in Sheep. HADLEY, W. M., BURCHIEL,S. W., MCDOWELL, T. D., THILSTED, J. P., HIBBS, C. M., WHORTON,J. A., DAY, P. W., FRIEDMAN, M. B., and STOLL, R. E. (1987).Fundam. Appl. Toxicol. 8, 236–242. Bacillus thuringiensisinsecticides (Bt) [Dipel (test substance D or Thuri-cide-HP(test substance T)] were administered in the diet for 5 monthsto castrated mixed ram-bouillet/merino sheep (24–34 kgat the beginning of the study) at a dose of 500 mg/kg/day (approximately10¹² spores per day). No treatment-related effect was seen onweight gain or clinical chemistry parameters nor were significantgross clinical changes observed. Several blood and tissue samplestaken just prior to the time the animals were killed or at necropsywere found to be positive for Bt when cultured. Detailed grossand microscopic pathologic examination of the sheep revealedseveral incidental lesions. However, the only lesion that mayhave been associated with the treatment was lymphocytic hyperplasiain Peyer's patches seen in the cecum of three sheep and it wasnot considered to be clinically significant.     

Sudden Death Mortality in Implantable Cardioverter Defibrillator Patients

Implanfable Cardioverter defibrillator (ICD) prevention of sudden cardiac death (SCD) is not absolute and our experience was reviewed to determine the frequency and nature of SCO in this population. The incidence and cause of mortality in 56 consecutive patients, who underwent ICD implantation beginning May 1982 with follow-up through May 19, 1990 were analyzed. Twenty-one patients died, 33% of the mortality was due to SCD, and 52% of deaths may be considered arrhythmic. The cumulative 1, 3, and 5 year SCD survivals were 93%, 89%, and 75%. All seven patients dying of SCD presented initially with SCD, all received previous shocks prior to SCD, and two of the seven patients had devices that were probably inactive at the time of death. We conclude that ICDs reduce but by no means eliminate arrhythmic death, particularly in those at highest risk for SCD. Arrhythmic death remained the most common cause of death in this population.     

Unrelated donor bone marrow transplantation for children and adolescents with aplastic anaemia or myelodysplasia

Allogeneic transplantation from an HLA-matched family member has been shown to be effective in reconstituting normal haemopoiesis in young people with severe cytopenias, classified as myelodysplastic syndrome (MDS) or severe aplastic anaemia (SAA). Unrelated donor transplant is a therapeutic choice for patients without a suitable family member donor. We report the outcome of seven patients < 20 years old with SAA and 10 with MDS treated with BMT from an HLA A,B DRB1 matched ( n  =8) or A or B locus mismatched ( n  =9) unrelated donor at the University of Minnesota between March 1988 and August 1995. Primary graft failure occurred in two patients and secondary graft failure in one, who was subsequently successfully engrafted with a second donor marrow infusion. Grades II–IV GVHD occurred in 10/16 (63%), and grades III–IV in 6/16 (37%) evaluable patients. Nine of the 17 patients (six with MDS and three with SAA) survive with full donor chimaerism, a median of 1.2 years post-BMT (range 3 months to 7 years). We recommend early referral for consideration of unrelated donor BMT for young patients with MDS, and patients with SAA without response to immunosuppression.