Long-term vardenafil therapy improves hemodynamics in patients with pulmonary hypertension.

The phosphodiesterase-5 (PDE-5) inhibitor, sildenafil, has been reported to produce sustained pulmonary vasodilatation in patients with pulmonary hypertension (PH). Recently, vardenafil, a more potent and selective PDE-5 inhibitor than sildenafil, has been approved for the treatment of erectile dysfunction. However, the long-term effects of oral vardenafil in patients with PH are unknown. We studied five consecutive patients with PH; one with primary pulmonary hypertension, two with chronic pulmonary thromboembolism, one with Eisenmenger syndrome (ventricular septal defect) and one with secondary pulmonary hypertension after a ventricular septal defect closure operation. In an acute hemodynamic trial, vardenafil (5 mg) significantly decreased both the pulmonary vascular resistance (PVR) and systemic vascular resistance (SVR) with an increase in cardiac output. In a chronic hemodynamic trial, the maintenance dose of vardenafil (10 to 15 mg) for 3 months significantly decreased the PVR, but not the SVR, with a 20.7% reduction of the PVR/ SVR ratio. Plasma brain natriuretic peptide (BNP) levels were also significantly decreased after 3 months. This pilot study demonstrates that long-term oral vardenafil therapy may be a safe and effective treatment for patients with PH.     

Tl-201 myocardial images in a patient with dialated cardiomyopathy, who finally received heart transplantation

The patient responded to treatment at the first onset of heart failure but gradually became irresponsive to treatment, experiencing fatigue and malaise as the chief complaints and suffering from gradually progressive decrease in exercise capacity and body weight. Dose of DOA gradually increased to maintain well clinical state of the patient. Unusual for heart failure, he had bradycardia as the basal rhythm without showing a tendency for tachycardia. Cardiac catheterization revealed pulmonary hypertension and low cardiac output, however, left ventricular ejection fraction was 37%. There were no notable changes in ultrasonic cardiogram or CTR through the clinical course. Tl-201 myocardial images and pulmonary perfusion images showed gradual worsening corresponding to progressive worsening of clinical state. From these findings, the patient was determined as a candidate for heart transplantation.     

Symmetrical brainstem encephalitis caused by herpes simplex virus

We describe a 53-year-old man with herpes simplex virus (HSV) brainstem encephalitis diagnosed based by positive HSV immunoglobulin M antibodies from cerebrospinal fluid. The MRI findings of this case had three unique features. First, the lesions were symmetrical. Second, the lesions may have been associated with reactivation of HSV infection in the region of the trigeminal nerve. Third, diffusion-weighted and apparent diffusion coefficient (ADC) imaging, conducted for the first time on an HSV brainstem encephalitis case, suggested that the lesions were associated with vasogenic edema.     

Sustained ventricular tachycardia responsive to verapamil in patients with hypertrophic cardiomyopathy. Clinical and electrophysiological assessment of drug efficacy

Recently, we examined 2 cases of hypertrophic cardiomyopathy (HCM) presenting with sustained ventricular tachycardia (VT). One case was a 62 year old male with midventricular hypertrophy and monomorphic sustained VT. After admission, the efficacies of procainamide, disopyramide, aprindin, flecainide, mexiletine and verapamil were evaluated by means of continuous electrocardiographic monitoring. Verapamil prevented the recurrence of sustained VT and markedly reduced the frequency and number of runs of nonsustained VT. In the electrophysiologic study, rapid VT was induced by double extrastimuli at the right ventricular apex. Intravenous verapamil at a dose of 10 mg prevented the induction of VT. The patient was discharged on verapamil and remains asymptomatic after 3 months of follow up. The other case was a 34 year old female who was a survivor of cardiac arrest. Monomorphic VT was observed on emergency admission and was converted to sinus rhythm by direct current cardioversion after resuscitation. In the electrophysiologic study, rapid VT was induced by double extrastimuli at the right ventricular outflow tract. Verapamil at a dose of 10 mg prevented the induction of VT. These 2 cases of HCM are rare in that they presented with sustained VT. It is also of interest that verapamil, which has been used conventionally in HCM, prevented VT.     

Drug-induced hypersensitivity nephritis: lymphocyte stimulation testing and renal biopsy in 10 cases

The pathomorphological and clinical findings were investigated in 10 cases of drug-induced hypersensitivity nephritis. Hypersensitivity due to drugs was strongly suggested by the lymphocyte stimulation test in all patients. The offending drugs included penicillin, cephem derivatives, nonsteroidal anti-inflammatory drugs, and minocycline. All patients developed acute renal failure shortly after administration of regular doses of the drugs. Allergic symptoms plus a raised level of serum IgE or eosinophilia were seen in 7 patients. The remaining 3 patients receiving nonsteroidal anti-inflammatory drugs had no allergic symptoms, but developed severe proteinuria. Eight patients without severe glomerular damage recovered after withdrawal of the offending drugs and temporal dialysis and/or steroid therapy. Renal biopsies revealed tubulitis and tubular epithelial degeneration with interstitial edema as the common characteristic findings. Granulomatous lesions were occasionally observed. Multinucleated giant cells found in the granulomas were positive for LN-3 which is compatible with HLA-DR antigen. The glomeruli appeared normal, except in 2 cases in whom crescentic glomerulonephritis and thrombotic microangiopathy were seen. Our study suggests that the lymphocyte stimulation test and renal biopsy are the most useful means to confirm the diagnosis and provides further evidence for the participation of cell-mediated immunity in the pathogenesis of drug-induced hypersensitivity nephritis.     

Molecular cloning and sequence determination of the peplomer protein gene of feline infectious peritonitis virus type I

Summary cDNA clones spanning the entire region of the peplomer (S) gene of feline infectious peritonitis virus (FIPV) type I strain KU-2 were obtained and their complete nucleotide sequences were determined. A long open reading frame (ORF) encoding 1464 amino acid residues was found in the gene, which was 12 residues longer than the ORF of the FIPV type II strain 79–1146. The sequences of FIPV type I and mainly FIPV type II were compared. The homologies at the N- (amino acid residues 1–693) and C- (residues 694–1464) terminal halves were 29.8 and 60.7%, respectively. This was much lower than that between FIPV type II and other antigenically related coronaviruses, such as transmissible gastroenteritis virus of swine and canine coronavirus. This supported the serological relatedness of the viruses and confirmed that the peplomer protein of FIPV type I has distinct structural features that differ from those of antigenically related viruses.     

Hemopoietic neoplasms in lethally irradiated mice repopulated with bone marrow cells carrying the human c-myc oncogene: a repopulation assay.

Bone marrow (BM) cells from two transgenic mice carrying the human c-myc oncogene were separately harvested, and each sample was injected into 25 lethally irradiated mice. We observed the contribution of the myc gene to the occurrence of hemopoietic neoplasms in the BM-repopulated mice, establishing a new experimental system for analyzing oncogene expression in the hemopoietic system in vivo. The hybrid gene that was transferred into the original transgenic mice was a combination of the human c-myc gene with a regulatory unit consisting of a murine immunoglobulin-heavy chain with an SV40 early-T promoter gene (Ig/Tp-myc). Among the transgenic lines, the tested BM cells were chosen from two lines that had been low-prone in leukemia; in these lines hemopoietic neoplasms did not appear for greater than or equal 200 days after birth. Lethally irradiated controls received BM cells from litters of transgenic mice that did not carry c-myc. The lifetime incidence of hemopoietic neoplasms was 94% and 91% in the two groups of mice repopulated with myc+ BM. By contrast, only 15% of control mice with myc- BM developed hemopoietic lesions. The incidence of hemopoietic malignancies combined with nonthymic lymphomas and myeloma cases (88% and 65%) was higher in the repopulated mice than the incidence of pre-B cell lymphomas in the original transgenic lines (56%). Thirty-two of the 40 myc+ mice that were examined showed the presence of the transferred gene in either the normal hemopoietic tissue or in the hemopoietic neoplasm. Furthermore, 18 of 22 hemopoietic neoplasms studied by Northern hybridization expressed mRNA from the transgenic gene; in other four neoplasms, expression was weak or absent.