Impact of Atrial Fibrillation Termination on Clinical Outcome after Ablation in Relation to the Duration of Persistent Atrial Fibrillation

Background: Whether procedural termination of persistent atrial fibrillation (AF) is necessary for optimal clinical efficacy still remains controversial. We sought to characterize the patients with persistent AF in whom procedural AF termination impacted an improved clinical outcome after ablation. Methods: We retrospectively assessed 132 patients (61.0 ± 9.3 years, 114 males) undergoing catheter ablation of persistent AF (duration 3 years, median). A stepwise ablation approach including pulmonary vein isolation and atrial substrate ablation targeting complex fractionated and high‐frequency electrograms was performed with desired endpoint of AF termination. Results: Overall, 90 patients (68%) were free from recurrent arrhythmias at 20 ± 11 months of follow‐up after one or two procedures. The left atrial diameter and continuous AF duration according to medical history were associated with the outcome (P = 0.002 and P< 0.001, respectively). In multivariate Cox regression analysis, the continuous AF duration was the only independent predictor of recurrent arrhythmias (hazard ratio 1.17, 95% confidence interval 1.10–1.23, P < 0.001). In patients with AF duration of ≥3 years, the clinical success was comparable regardless of whether AF termination was achieved or not (log‐rank, P = 0.27). In the remaining patients with AF duration of <3 years, procedural AF termination was associated with a higher arrhythmia‐free rate than when AF was sustained after ablation (log‐rank, P = 0.023). Conclusion: Extensive ablation to terminate AF might not be warranted in patients with a longer AF duration. On the contrary, procedural AF termination could be associated with maintenance of sinus rhythm in patients with a shorter AF duration with a less proarrhythmic substrate. (PACE 2012;35:1436–1443)     

Effect of varicella zoster virus antigen-antibody complexes on hydrogen peroxide generation by human polymorphonuclear leukocytes

Hydrogen peroxide (H₂O₂) generation by human polymorphonuclear leukocytes (PMN) incubated with varicella zoster virus (VZV) antigen was studied by cytofluorography. Hydrogen peroxide generation was detected in the presence of VZV-seropositive sera. When seropositive sera were heat-inactivated, H₂O₂ generation was reduced. When PMN were pre-incubated with Leu-1 1b, a monoclonal antibody to the Fc receptor on PMN, H₂O₂ generation was also reduced. These results suggest that VZV antigen-antibody-complement complexes induce H₂O₂ generation by PMN after these complexes attach to Fc receptors on PMN.     

Synthesis and solubility properties of peptide fragments of human hemoglobin α-chain (123-136)

The solubility prediction method for protected peptides was successfully applied to relatively small peptide fragments of human hemoglobin α-chain (123-136) which contained various polar amino acid residues such as Asp(OBzl), Glu(OBzl), Lys(Z), Ser(Bzl), and Thr(Bzl). As reported previously for hydrophobic peptides and human proinsulin C-peptide fragments, solubility data indicated that the insolubility of protected peptides having a <P_C > value below 0.90 appeared to begin at the octa- or nonapeptide sequence level and that β-sheet structure played an important role in the insolubility of peptides. When a peptide has a β-sheet structure in the solid state, we can clearly determine the critical chain length for peptide insolubility, the solubility dependence on solvent properties, and the solubility independence of amino acid compositions of peptides.     

Microheterogeneity of serum transferrin in the diagnosis of hepatocellular carcinoma

Heterogeneous reactivity of human serum transferrin (Tf) with lectins was analysed using patient sera to determine whether it can be used to distinguish patients with hepatocellular carcinoma (HCC) from those with liver cirrhosis (LC). Microheterogeneity of Tf was analysed by crossed immunoaffinity electrophoresis (CIAE) with concanavalin A (Con A) and Lens culinaris agglutinin (LCA). Sample sera from 58 patients with HCC, 43 patients with LC and 10 normal controls were used in this study and the results were evaluated statistically. The increments of Con A-non-reactive (C1) and -weakly reactive (C2) species of Tf were observed in HCC compared with those of LC and Norm. Significant increase in the combined percentage of Con A- C1 + C2 species was also revealed in HCC (35.5 ± 8.5%, mean ± s.d.) compared with those of LC (29.1 ± 6.8%; P < 0.001) and normal controls (17.1 ± 2.3%; P < 0.001). The elevation of LCA-reactive (L2) species of Tf was recognized in HCC (8.2 ± 3.8%) in comparison with those of LC (4.8 ± 3.1%; P<0.001) and normal controls (1.3 ± 1.7%; P < 0.001). The increment of C1+C2 species and/or L2 species of Tf was observed in 78% (sensitivity) of patients with HCC. The specificity, the positive predictive value and the overall accuracy were 81, 88 and 72%, respectively. Positive ratio of C1+C2 and/or L2 species was 77 and 70% in alpha-fetoprotein low and -high producing HCC patients, respectively. These results indicate that the microheterogeneity analysis of human serum Tf is useful for distinguishing patients with HCC from those with LC and normal controls.     

Management of meconium aspiration syndrome by tracheobronchial lavage and replacement of Surfactant-TA

Meconium aspiration syndrome creates mechanical airway obstruction with air trapping and atelectasis. Tracheobronchial saline lavage to dislodge meconium may precipitate respiratory distress, a wet lung appearance and respiratory failure. Two case studies are reported in which meconium aspiration resulted in mechanical obstruction and displacement of surfactant and in whom tracheobronchial saline lavage and artificial surfactant replacement reversed respiratory failure.     

Mechanism for Drug Absorption from Rat-liver Surface Membrane: Effect of Dose and Transport Inhibitors on the Pharmacokinetics of Phenol Red

We examined the effect of dose and transport inhibitors on the pharmacokinetics of phenol red as a model drug after application to rat liver surface in-vivo, employing a cylindrical glass cell (i.d. 9 mm, area 0·64 cm²), to elucidate the mechanism for drug absorption from liver surface membrane. Absorption ratios of phenol red in 6 h were determined to be 91·1, 91·8 and 89·9% at a dose of 0·3, 1 and 3 mg, respectively. The AUC value for plasma concentration profile of phenol red was proportional to the dose. It is thus suggested that the absorption process of phenol red from rat liver surface does not approach saturability. The time course of the remaining amount of phenol red in the glass cell obeyed first-order kinetics at a dose of 0·3 mg, and its rate constant K_a was calculated to be 0·0069 min^?1. Moreover, no significant difference was seen in the K_a value within the dose range of 0·3-3 mg, which was estimated by curve fitting of the plasma concentration profile of phenol red after application to rat liver surface in the two-compartment model with first-order absorption. 2,4-Dinitrophenol (0·3 mg) and probenecid (0·5 and 1 mg), inhibitors of metabolic energy and anion transport, respectively, had no significant effect on the pharmacokinetics of phenol red after application to rat liver surface. These data demonstrate that a specific transport mechanism such as active transport is not involved in phenol red absorption from rat liver surface membrane.     

Case report: Portal-systemic encephalopathy due to a congenital extrahepatic portosystemic shunt

We present a case of portal-systemic encephalopathy due to a congenital splenorenal shunt. A 69 year old woman was admitted to hospital because of recurrent episodes of disturbed consciousness. The present episode had begun 3 months prior to admission. Although the patient demonstrated mildly slurred speech, the remainder of her neurological examination was unremarkable. She showed no clinical signs of portal hypertension and her liver function, except for a serum hepaplastin test of 58% and an ICG retention rate of 28% at 15 min, was normal. Her serum ammonium level was 210 μg/dL. The venous phase of a superior mesenteric arteriogram revealed a splenorenal shunt and narrowing of the portal vein, which was 4 mm in diameter. The histological findings, demonstrated by a needle liver biopsy specimen, were consistent with mild fibrosis and lymphocytic infiltration. Following the diagnosis of a splenorenal shunt in the absence of liver cirrhosis, ligature of the shunt was performed with a splenectomy. The portal vein pressure after ligature of the shunt rose from 12.5 to 18.8 mmHg. This shunt was thought to be of congenital origin. The high preoperative serum ammonia concentration decreased to the normal range postoperatively and the serum hepaplastin test and ICG retention rate similarly improved postoperatively. A follow-up superior mesenteric arteriogram was performed during the venous phase, demonstrating resolution of the shunt and decreased portal vein narrowing. The patient has suffered no further episodes of disturbed consciousness postoperatively.     

Impact of sociodemographic and diabetes-related characteristics on depressive state among non-insulin-dependent diabetic patients

Abstract  One hundred and fifty-one non-insulin-dependent diabetic patients were assessed to detect sociodemographic, psychological and disease-related characteristics that were related to depressive state among diabetic patients. Depressive state in the patients was correlated with poor social support and low economic status, premorbid neurotic personality and the presence of complications, retinopathy in particular. However, depressive state did not correlate with age, gender, education, serum level of HbA_1C or duration of diabetes. The severity of the depressive state in diabetic patients may vary with the cultural background of the patient and/or the country in which he or she is living. In treating diabetic patients, doctors need to pay special attention to these factors.