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.     

Direct injections of calcitriol into enlarged parathyroid glands in chronic dialysis patients with severe parathyroid hyperfunction

Summary: Severe secondary hyperparathyroidism in chronic dialysis patients has been recently treated by supraphysiological concentration of calcitriol achieved through pulse therapy. However, there are many patients resistant to this therapy, who usually have larger parathyroid gland(s). to overcome this resistance, calcitriol was injected directly into the enlarged glands under ultrasonographic guidance. We injected 70–90% of the calculated gland volume of calcitriol solution (1 μg/mL) into the glands of 7 patients three times per week for 2 weeks. the parathyroid hormone (PTH) levels decreased significantly after 2 weeks of direct injections of calcitriol. Following a further 4 weeks of calcitriol pulse therapy, PTH levels remained suppressed and serum alkaline phosphatase activity and the volume of parathyroid glands also decreased. During the long-term follow up, five patients remained well controlled with calcitriol pulse therapy, while two patients needed ethanol injections to control hyperparathyroidism. Although we could not completely rule out a toxic effect of the vehicle, direct injection of calcitriol into parathyroid glands may be another treatment option for chronic dialysis patients. Our data further support the important role of resistance of parathyroid cells to calcitriol in the pathogenesis of parathyroid hyper function in uraemic patients.     

Surgical exploration for renal cyst: two-case report]

A 59-year-old male was admitted to our clinic for further examination of the calcified renal cyst discovered incidentally on medical workup elsewhere. CT showed a left renal cyst associated with calcification. Ultrasound-guided puncture of the renal cyst was not successful because of thickness of the cystic wall. Renal angiography showed hypervascularity of the cystic wall. Association of renal cell carcinoma could not be ruled out, therefore the exploration was performed. Histological examination revealed benign renal cyst with calcification. A 27-year-old male presented with the chief complaint of left flank pain. Following examinations by US, CT and MRI, a renal cyst associated with renal cell carcinoma was highly suspected. Subsequent exploration revealed cluster of cysts with a yellowish lesion a few mm in diameter. Frozen section revealed no malignancy, and cystic fluid was not hemorrhagic. Therefore as many cystic walls as possible were removed without nephrectomy. Histological examination of the permanent specimen revealed renal cell carcinoma. Renal cyst associated with renal cell carcinoma was regarded as rare clinical entity, but such cases are reported in increasing number in recent years. We report such cases and review the pertinent literature in this paper.     

Intracellular vesicular stomatitis virus nucleocapsids and virions visualized by surface spreading

Spreading of cells on a solution surface could visualize vesicular stomatitis virus nucleocapsids and virions in infected cells easily and clearly without the need for any purification. Characteristic structures observed by the spreading of the infected cells are described and discussed.     

Simultaneous analysis of shikimate-derived secondary metabolites in Lithospermum erythrorhizon cell suspension cultures by high-performance liquid chromatography

A high-performance liquid chromatography (HPLC) analysis system based on a water-acetonitrile gradient program was established for simultaneous quantification of shikimate-derived secondary metabolites in cultured cells of Lithospermum erythrorhizon. The cells cultured in pigment production medium (M-9) are capable of producing five highly hydrophilic compounds such as p-hydroxybenzoic acid-O-glucoside and lithospermic acid B, as well as eleven lipophilic compounds including echinofuran B and acetylshikonin. In addition to the wide polarities of those compounds, many of them are unstable under light, dryness, oxygen and heating. Thus, a new extraction procedure for all these compounds was also established by use of ultrasonication under ice-water chilling with MeOH as the solvent. This procedure was applied to the quantitative analyses of these compounds in cell cultures and hairy root cultures of Lithospermum, and in the intact plants as well.     

Simultaneous infection with human herpesvirus-6 and measles virus in infants

Two infants (4 and 5 months of age) with a febrile episode for 3 and 5 days, respectively, developed skin rashes after the fever subsided and were diagnosed as exanthem subitum. The rash continued for 5 days followed by mild-to-moderate pigmentation. Human herpesvirus-6 and measles virus, which were confirmed by a specific immunofluorescence assay and by electron microscopy, were isolated simultaneously from blood in the acute stage of the disease but not from the convalescent stage. The titer of the herpesvirus-6 in blood was greater than that of measles. Specific serologic assays showed marked seroconversion against human herpesvirus-6 but not to measles virus. The results suggest that dual infection with human herpesvirus-6 and measles virus results in atypical exanthem subitum or modified measles with unique immunologic responses.     

The 5' coding sequence of IL-2 receptor alpha chain mRNA mediates mRNA stabilization by HTLV-1 Rex.

The interleukin-2 receptor alpha chain (IL-2R alpha) is a T-cell growth factor receptor and is known to be induced in helper T cells by infection with human T-cell leukaemia virus type-1 (HTLV-1). The Rex protein of HTLV-1 has been shown to stabilize IL-2R alpha mRNA. Although the 3' untranslated region of many RNA has been regarded as a key element for stabilization, we found that the first 300 bases of the IL-2R alpha protein coding sequence were necessary for stabilization of the mRNA. As the first 201 bases were not sufficient for this effect, we conclude that the bases at position 201-300 downstream of the AUG start are important for stabilization.     

Long-term potentiation in the optic tectum of rainbow trout

We examined synaptic plasticity in the optic tectum of rainbow trout by extracellular recordings. We found that the field-excitatory postsynaptic potential in the retinotectal synapses was potentiated by repetitive stimuli of 1.0 Hz for 20 s to the retinotectal afferents. The long-term potentiation (LTP) developed slowly, and was maintained for at least 2 h. Applications of an antagonist for N-methyl-D-aspartic acid (NMDA) receptors or Mg²⁺-free saline showed that activation of NMDA receptors was required to form the LTP beyond the induction period. The present findings indicate that presynaptic stimulation in the retinotectal synapses causes LTP mediated by NMDA receptors in the optic tectum of rainbow trout.