Left ventricular fibroma in an aged patient: Report of a case

We report herein the case of a 77-year-old man with a left ventricular tumor originating from the papillary muscle of the left ventricular wall, in whom a successful tumor resection with mitral valve replacement was performed. The pathological diagnosis of the tumor was confirmed as cardiac fibroma. His postoperative course was uneventful and he is currently well with no signs of recurrence 2 years after surgery.     

Reduction in Internal Carotid Arterial Blood Flow Velocity in Children During Antiepileptic Drug Therapy with Clinical Dosages

Summary: We studied the effect of antiepileptic drugs (AEDs) on internal carotid artery (ICA) blood flow velocity, as an index of total cerebral blood flow (CBF). The subjects were 45 newly diagnosed children with febrile convulsion or epilepsy who were seizure-free for a period long enough not to affect the results. They had no neurologic deficit, received fixed monotherapy, and were examined by a noninvasive Doppler ultrasound method, in comparisonwith 13 age-matched normal volunteers with no AED. In 30 patients, the measurements were performed before and after AED administration [10 with phenobarbital (PB), 10 with carbamazepine (CBZ), and 10 with valproate (VPA)], and performed before and after AED discontinuation in the remaining 15 patients (all with PB). Normal volunteers underwent the two consecutive examinations with a mean interval equal to that of the entire patient group, and there was no difference in velocity values between the measurements. In patients receiving CBZ or VPA, a significant reduction was noted in blood flow velocity after drug administration. Although velocity values in the patients receiving PB did not change after drug administration, they were significantly increased after complete discontinuation. In the present study, a slight but significant reduction in CBF caused by AED administration at therapeutic doses in children was suggested.     

Phorbol ester potentiates alpha 1-adrenoceptor-mediated positive inotropic effect in rat papillary muscle

Tumor-promoting phorbol esters may alter alpha 1-adrenoceptor-mediated cardiac response by stimulating protein kinase C activity. We investigated the effect of phorbol-12,13-dibutyrate (PDBu) on the positive inotropic effect (PIE) in rat left ventricular papillary muscle. PDBu (1-100 nM) potentiated the phenylephrine (PE)-induced PIE in a dose- and time-dependent manner. The PIE induced by PE and PDBu was abolished by pretreatment with 3 x 10(-7) M prazosin. PDBu also enhanced PE-induced slow responses 2- to 3-fold. These results suggest that PDBu enhances alpha 1-adrenoceptor-mediated PIE by potentiating slow Ca2+ channels, presumably through the activation of protein kinase C.     

Spermidine/Spermine N-Acetyltransferase, a New Biochemical Marker for Epithelial Proliferation in Rat Bladder

We examined the activity of spermidine/spermine N ¹-acetyltransferase (SAT), a rate-limiting enzyme of the biodegradation of polyamines, in N -butyl- N -(4–hydroxybutyI)nitrosamine-induced transitional cell carcinoma (TCC) and melamine-induced papillomatosis of rat bladder, and compared the activity to that of ornithine decarboxylase (ODC). Both activities were higher in both lesions than in control rats. The difference between SAT and ODC activities in cancerous tissue and papillomatosis was not significant. Cells stained for proliferating cell nuclear antigen (PCNA) were abundant in papillomatosis. TCC had areas with much PCNA. The results indicated that an elevation of SAT activity occurs in both reversible and irreversible proliferation of bladder epithelium and could be important in bladder carcinogenesis.     

Early gamma interferon responses in lethal and nonlethal murine blood-stage malaria.

This study was undertaken to explore early differences in cytokine production during nonlethal and lethal blood-stage murine malaria infections. Cytokine analysis of spleens during these infections showed that the principal difference between two nonlethal and two lethal Plasmodium species was the production of gamma interferon 24 h after infection with nonlethal parasites. In contrast, no increases in interleukin-4 production were observed in the first 24 h and tumor necrosis factor alpha levels increased equally in both nonlethal and lethal infections. During the later phase of infection with nonlethal parasites, both gamma interferon and interleukin-4 levels increased markedly a few days before parasite clearance. Early increases in gamma interferon production in nonlethal infections of Plasmodium yoelii and Plasmodium chabaudi were dose related and increased significantly with the size of the inoculum. Studies with the nonlethal P. yoelii suggest that the early gamma interferon response is mediated by T cells and natural killer cells, as it was reduced in athymic mice and in mice depleted of their natural killer cells by treatment with specific antiserum. Infecting mice with increasing numbers of lethal P. yoelii and Plasmodium berghei parasites did not increase the amount of gamma interferon, interleukin-4, and tumor necrosis factor alpha produced in a dose-dependent fashion. We conclude that one consequence of the early production of gamma interferon and tumor necrosis factor-alpha, particularly after nonlethal P. yoelii infection, may be to adjust the balance of T-helper cell subset activation, and probably that of other immune responses, so as to enhance the mechanisms that are essential for elimination of the parasites. This suggests that a successful vaccine should contain antigens capable of inducing such responses.