Ventricular Late Potential in Patients with Apparently Normal Electrocardiogram; Predictor of Brugada Syndrome

Backgrounds: Brugada syndrome can be overlooked due to its dynamic change in its electrocardiogram (ECG) manifestation. We hypothesized that positive ventricular late potential (VLP) in patients with nonspecific ECG would predict the inducible coved ST elevation (type‐1 Brugada ECG) and the patients at high risk. Methods: Thirty‐four patients of nonspecific ECG without structural heart disease were eligible for this study. All patients were referred for evaluation of syncopal episodes and/or cardiac arrest and/or frequent episodes of ventricular premature contractions. We assessed the correlation between baseline VLP and the alteration to a drug‐induced type‐1 Brugada ECG, and also evaluated the diagnostic accuracy of positive VLP in normal ECG subjects for the appearance of a drug‐induced type‐1 Brugada ECG. Results: Twenty‐one patients presented positive VLP and 13 patients showed negative VLP. Parameters of VLP (fQRSd, RMS₄₀, LAS₄₀) presented significant correlation with the alteration to a type‐1 ECG by pilsicainide. VLP demonstrated high sensitivity and negative predictive value for the prediction of type‐1 Brugada ECG. Furthermore, in their follow‐up, at least two cases of ventricular fibrillation were recognized in 21 of positive VLP patients with apparently normal ECGs. Conclusions: VLP in apparently normal ECG can predict the alteration to a drug‐induced type‐1 Brugada ECG and unmask the patients at risk. (PACE 2010; 33:266–273)     

Acute Effects of Different Atrial Pacing Sites in Patients with Atrial Fibrillation: Comparison of Single Site and Biatrial Pacing

It has been reported that a trial single site or biatrial pacing can suppress the occurrence of AF. However, its mechanism remains unclear. The study population included 32 patients with AF (n = 20: AF group), or without paroxysmal AF (n = 12: control group). The mechanism and efficacy of atrial pacing were investigated by electrophysiological studies to determine which was more effective for suppressing AF induction; single site pacing of the right atrial appendage (RAA) or distal coronary sinus (CS-d), or biatrial (simultaneous BAA and CS-d) pacing. In the AF group, AF inducibility was significantly higher with BAA extrastimulus during RAA (12/20; P < 0.0001) or biatrial paced drive (7/20; P < 0.01) than during CS-d paced drive (0/20). In the control group, AF was not induced at any site paced. In the AF group, the conduction delay and other parameters of atrial vulnerability significantly improved during CS-d paced drive. The atrial recovery time (ART) at RAA and CS-d was measured during each basic pacing mode. ART was defined as the sum of the activation time and refractory period, and the difference between ARTs at RAA and CS-d was calculated as the ART difference (ARTD). The ARTD was significantly longer during BAA pacing in the AF group than in control group (155.0 +/- 32.8 vs 128.8 +/- 32.9 ms, P < 0.05). In the AFgroup, ARTDs during biatrial (52.0 +/- 24.2 ms) and CS-d pacing (51.7 +/- 26.0 ms) were significantly shorter than ARTD during RAA pacing. The CS-d paced drive was more effective for suppressing AF induction than biatrial or RAA paced drive by alleviating conduction delay. CS-d and biatrial pacing significantly reduced ARTD compared with RAA pacing.     

A negative component on event related potential recorded in the drowsy state

Abstract Behavior of event related potential (ERP) components in the drowsy state was examined in nine subjects using oddball paradigm. A component with peak latency of 300 msec, N300, was superimposed on ERP in the drowsy state. N300 appeared also in stage 1 of NREM sleep and closely resembled vertex sharp wave evoked by sound stimulation in both scalp distribution and peak latency. It was suggested that N300 recorded in the drowsy state and vertex sharp wave recorded in stage 1 of NREM sleep are generated by the identical synchronizing mechanism in the brain.     

Bladder cancer discovered by ovarian metastasis: Cytokeratin expression is useful when making differential diagnosis

A 49-year-old woman underwent hysterectomy and bilateral adnexectomy after the diagnosis of a right ovarian tumor with paraaortic and pelvic lymph node metastases. The pathological diagnosis was undifferentiated carcinoma of the ovary. After the operation, a bladder tumor was discovered during the evaluation for microscopic hematuria. The bladder tumor was pathologically diagnosed as transitional cell carcinoma, pT1b, G3. Although the pathological findings of the bladder cancer and ovarian cancer were very similar, we could diagnose primary bladder cancer with ovary and lymph node metastases according to the immunohistochemical staining pattern of cytokeratins 7 and 20. Herein, the clinical usefulness of immunohistochemical staining using cytokeratins for making a differential diagnosis of the origin of a tumor in the pelvic cavity is demonstrated.     

Asthenozoospermia: Possible association with long-term exposure to an anti-epileptic drug of carbamazepine

Little attention has been paid to infertility in men with epilepsy and little information exists about the mechanisms by which anti-epileptic drugs affect spermatogenesis or sperm function. We report a case of a male infertility patient with asthenozoospermia during long-term treatment with anti-epileptic drugs. A 29-year-old man had continued treatment with anti-epileptic drugs under the diagnosis of epilepsy for 13 years. He and his wife had been examined and treated as an infertile couple for 3 years. The patient was found to have no motile sperm with a normal sperm count, while taking a dose of 400 mg/day of carbamazepine. On suspicion of an adverse effect of carbamazepine, he was switched to phenytoin monotherapy. One month after that, sperm motility was vastly improved (65%) and they conceived a child 5 months after that. One must be cautious in extrapolating from a case report, but these findings strongly suggest a direct effect of carbamazepine on spermatic function.     

Synthesis and conformation of the trimeric coiled-coil segment of laminin*

A disulfide linked 95-mer parallel hetero-trimeric active site segment of laminin was designed and synthesised. The three subunits, A (32-mer), B1 (30-mer) and B2 (33-mer), were prepared by Boc-based solid-phase peptide synthesis involving a two-step trimethylsilyl bromide-thioanisole and HF deprotection procedure. The interlinking of the three subunits was accomplished by the stepwise selective formation of two disulfide bridges using air-oxidation and thallium (III) trifluoroacetate oxidation. The conformations of the synthetic peptides were studied by circular dichroism (CD) spectroscopy, showing that the hetero-dimer, B1-B2, one of the homo-dimers, B1-B1, and the trinier are 30 to 40% in the α-helical conformation in aqueous buffer. Variable temperature CD studies demonstrated that the trimer is considerably more stable (melting temperature (Tm) = 61°) than the hetero-dimer, B1-B2 (Tm = 36°).     

Bisphosphonate induces apoptosis and inhibits pro-osteoclastic gene expression in prostate cancer cells

AIM: Bisphosphonates are well established for the management of cancer-induced skeletal complications. Recent studies suggest that bisphosphonates promote apoptosis of cancer cells as well as osteoclasts in bone metastatic sites. To determine the direct effects of bisphosphonate on prostate cancer, we examined the effects of minodronate on prostatic cancer cell growth and the expression of apoptosis-related proteins and osteoclastogenic factors. METHODS: PC-3, DU145 and LNCaP cells were treated with amino-bisphosphonate minodronate. Then proliferation, apoptosis and expression of bcl-2, bax, poly (ADP)-ribose polymerase (PARP), caspase-3, receptor activator of nuclear factor-kappaB ligand (RANKL), osteoprotegerin (OPG), matrix metalloproteinases-2 (MMP-2), and parathyroid hormone related protein (PTHrP) were assessed. RESULTS: The proliferation of prostatic cancer cells was inhibited by minodronate. DNA fragmentation and TUNEL-positive nuclei were observed in minodronate-treated PC-3 cells. Minodronate decreased bcl-2 expression and induced bax expression, caspase-3 activity and degradation of PARP in DU145 and PC-3 cells. Minodronate decreased expression of RANKL, PTHrP and MMP-2 in PC-3 cells. CONCLUSIONS: Our results suggest that bisphosphonate not only promotes apoptosis directly but also decreases pro-osteoclastic gene expression in prostate cancer cells.