Inhibition of inward rectifier K+ currents by angiotensin II in rat atrial myocytes: lack of effects in cells from spontaneously hypertensive rats.

We examined the effects of angiotensin II (Ang II) on inward rectifier K+ currents (IK1) in rat atrial myocytes. [125I]Ang II-binding assays revealed the presence of both Ang II type 1 (AT1) and type 2 (AT2) receptors in atrial membrane preparations. Ang II inhibited IK1 in isolated atrial myocytes with an IC50 of 46 nmol/l. This inhibition was abolished by the AT, antagonist RNH6270 but not at all by the AT2 antagonist PD123319. Treatment of cells with pertussis toxin or a synthetic decapeptide corresponding to the carboxyl-terminus of Gialpha-3 abolished the inhibition by Ang II, indicating the role of a Gi-dependent signaling pathway. Accordingly, Ang II failed to inhibit IK1 in the presence of forskolin, dibutyryl-cAMP or protein kinase A catalytic subunits. In spite of the increased binding capacities for [125I]Ang II, Ang II failed to affect IKI in cells from spontaneously hypertensive rats (SHR). AT, immunoprecipitation from atrial extracts revealed decreased amounts of Gialpha-2 and Gialpha-3 proteins associated with this receptor in SHR as compared with controls. The reduced coupling of AT, with Gialpha. proteins may underlie the unresponsiveness of atrial IK1 to Ang II in SHR cells.     

Effect of promoter methylation of the p16 gene on phosphorylation of retinoblastoma gene product and growth of hepatocellular carcinoma cells.

The biological significance of hypermethylation of p16 gene promoter in human hepatocellular carcinoma (HCC) cells remains to resolved. In order to clarify the significance of methylation of p16 gene promoter, we examined the methylation status of p16 gene in association with phosphorylation of retinoblastoma gene product (pRb) and cell growth in human HCC cell lines. The presence of methylation was examined by methylation-specific PCR. Expression and phosphorylation of p16 and pRb were examined by Western blot analysis. Genetic changes were analyzed by multiplex PCR and DNA sequencing. The effect of demethylation of p16 was assessed by cell growth. p16 gene promoter was methylated in HuH7 and HLF cells. The demethylating agent, 5-aza-2-deoxycytidine (5-Aza-CdR), upregulated p16 mRNA in HuH6 and HuH7 cells. 5-Aza-CdR increased p16 protein expression in HuH6, HuH7, and HLF cells, and it clearly decreased the phosphorylation level of pRb in HuH6, HuH7 and PLC/PRF/5 cells. Treatment with 5-Aza-CdR inhibited the growth of HuH7 cells. Homozygous deletion and significant mutations were absent. Methylation in the p16 promoter region is biologically significant, being associated with phosphorylation of pRb and cell growth in human HCC cells.     

Interferon increases serum thrombopoietin in patients with chronic hepatitis C

We measured serum thrombopoietin (TPO) in chronic hepatitis C treated with interferon (IFN). The platelet count before the therapy was 161.9 ×10⁹ ± 64.1 × 10⁹/l, which decreased to 116.3 × 10⁹ ±  48.4 × 10⁹/l 1 week after IFN therapy ( P  <0.01). On the other hand, serum TPO increased from 1.96 ± 0.60 fmol/ml to 2.68 ± 0.69 fmol/ml ( P  < 0.02). Contrary to a recent report that serum TPO was not altered in liver cirrhosis, these data indicate that serum TPO was increased in chronic hepatitis C in response to thrombocytopenia by IFN therapy.     

Severe exacerbation of hepatitis after short‐term corticosteroid therapy in a patient with “latent” chronic hepatitis B

Abstract: We present a case of severe exacerbation of hepatitis after short‐term corticosteroid therapy for chronic inflammatory demyelinating polyneuropathy (CIPD) with “latent” chronic hepatitis B showing no HBV‐related antigens and antibodies. After corticosteroid pulse therapy for CIPD, the patient had severe exacerbation of hepatitis twice. Although she did not show any hepatitis B virus (HBV)‐related antigens or antibodies, sequences of HBV were detected in serum and liver by a nested polymerase chain reaction. A sequence analysis of HBV at the second exacerbation showed that the G‐to‐A point mutation at nucleotide 1896 that converted codon 28 from tryptophan (TGG) to a stop codon (TAG) in the precore region resulted in amino acid change, which has been frequently observed in fulminant hepatitis and severe hepatitis in Japan.     

New combined anteversion technique in hybrid THA: cup-first procedure with CT-based navigation

European Journal of Orthopaedic Surgery & Traumatology - Combined anteversion (CA) technique (stem-first procedure) is generally accepted as the optimal technique to attain an appropriate CA...     

Serum levels of interleukin-10, interleukin-12 and soluble interleukin-2 receptor in chronic liver disease type C

BACKGROUND/AIMS: It is still unclear whether and how Th1/Th2 type cytokines are involved in the progression of chronic liver disease type C. We therefore examined serum levels of IL-10, IL-12 and sIL-2R (soluble IL-2 receptor) in association with clinical parameters in chronic liver disease type C, whereas IL-12 and sIL-2R represent Th1 cytokine and IL-10 does Th2 cytokine, respectively. METHODOLOGY: Serum levels of IL-10, IL-12 and sIL-2R were measured in 110 patients, including 36 with chronic hepatitis, 24 with liver cirrhosis and 50 with hepatocellular carcinoma in comparison with 19 normal individuals, by an enzyme-linked immunosorbent assay. In 9 chronic hepatitis patients, serum levels of these cytokines were measured before and after interferon therapy. In 28 with hepatocellular carcinoma, they were also measured before and after transcatheter arterial embolization. RESULTS: Serum levels of IL-10 in chronic hepatitis, liver cirrhosis and hepatocellular carcinoma were 3.9 +/- 1.8 pg/mL, 5.7 +/- 6.4 pg/mL and 5.6 +/- 8.9 pg/mL, respectively. IL-10 level was significantly correlated with level of y-globulin. Serum levels of IL-12 in chronic hepatitis, liver cirrhosis and hepatocellular carcinoma were 347.4 +/- 150.3 pg/mL, 365.2 +/- 130.7 pg/mL and 399.4 +/- 258.2 pg/mL. sIL-2R levels in chronic hepatitis, liver cirrhosis and hepatocellular carcinoma were 614.6 +/- 223.5 U/mL, 878.7 +/- 330.5 U/mL and 1037.9 +/- 412.0 U/mL. Serum levels of IL-12 and sIL-2R were significantly elevated on day 7 after interferon therapy compared to day 0 (p < 0.05 and p < 0.001, respectively), while no significant difference was seen in IL-10. Serum level of IL-10 was significantly elevated on day 3, and that of sIL-2R was elevated on day 3 and 7 after transcatheter arterial embolization, while that of IL-12 was decreased on day 3 and 7. CONCLUSIONS: The results of the present study suggest that Th1/Th2 type cytokines are changed in association with progression of chronic liver disease type C and in response to therapy.     

State-dependent blocking actions of azimilide dihydrochlo-ride (NE-10064) on human cardiac Na(+) channels.

BACKGROUND: Azimilide reportedly blocks Na(+) channels, although its mechanism remains unclear. METHODS AND RESULTS: The kinetic properties of the azimilide block of the wild-type human Na(+) channels (WT: hH1) and mutant DeltaKPQ Na(+) channels (DeltaKPQ) expressed in COS7 cells were investigated using the whole-cell patch clamp technique and a Markovian state model. Azimilide induced tonic block of WT currents by shifting the h infinity curve in the hyperpolarizing direction and caused phasic block of WT currents with intermediate recovery time constant. The peak and steady-state DeltaKPQ currents were blocked by azimilide, although with only a slight shift in the h infinity curve. The phasic block of peak and steady-state DeltaKPQ currents by azimilide was significantly larger than the blocking of the peak WT current. The affinity of azimilide predicted by a Markovian state model was higher for both the activated state (Kd(A) =1.4 micromol/L), and the inactivated state (Kd(I) =1.4 micromol/L), of WT Na(+) channels than that for the resting state (Kd(R) =102.6 micromol/L). CONCLUSIONS: These experimental and simulation studies suggest that azimilide blocks the human cardiac Na(+) channel in both the activated and inactivated states.