Mechanism of formation of elastin crosslinks

We examined the formation of quaternary pyridinium crosslinks of elastin formed by condensation of lysine and allysine residues using the model compounds propanal (allysine) and n-butylamine (lysine) under quasi-physiological conditions. The resulting pyridinium compounds were characterized and the structure compared with the known pyridinium crosslinks. Three pyridinium compounds were identified and the structures were identical with the skeleton of the crosslinking amino acids, desmosine (DES), isodesmosine (IDE), and pentasine. We concluded that a non-enzymatic pathway is available for the spontaneous generation of pyridinium crosslinks. To elucidate the intermediates and the mechanism of the formation of DES and IDE, we synthesized model intermediates from propanal and n-butylamine, and they were allowed to react in three kinds of solvents. Then, the products were analyzed by an ion-pair reverse-phase HPLC. The results of this model system indicated that DES and IDE can be formed by condensation of dehydromerodesmosine with dehydrolysinonorleucine and by condensation of allysine with dehydrolysinonorleucine, respectively. We also describe the mechanism of DES and IDE crosslinking.

Clinical usefulness of a multielectrode basket catheter for idiopathic ventricular tachycardia originating from right ventricular outflow tract

INTRODUCTION

It often is difficult to determine the optimal ablation site for idiopathic ventricular tachycardia (VT) originating from the right ventricular outflow tract (RVOT) when the VT or premature ventricular complex (PVC) does not occur frequently. The aim of our study was to evaluate the usefulness of a multielectrode basket catheter for ablation of idiopathic VT originating from the RVOT.

METHODS AND RESULTS

Radiofrequency (RF) catheter ablation was performed using a 4-mm tip, quadripolar catheter in 50 consecutive patients with 81 VTs originating from the RVOT with (basket group = 25 patients with 45 VTs) or without (control group = 25 patients with 36 VTs) predeployment of a multielectrode basket catheter composed of 64 electrodes. Deployment of the multielectrode basket catheter was possible and safe in all 25 patients in the basket group. Ablation was successful in 25 (100%) of 25 patients in the basket group and in 22 (88%) of 25 patients in the control group. The total number of RF applications and the number of RF applications per PVC morphology did not differ between the two groups. However, both the fluoroscopic and ablation procedure times per PVC morphology were shorter in the basket group than in the control group (36.8+/-14.1 min vs 52.0+/-32.5 min, P = 0.04; 60.0+/-14.6 vs 81.5+/-51.2 min, P = 0.05). This difference was more pronounced in the 29 patients in whom VT or PVC was not frequently observed.

CONCLUSION

The multielectrode basket catheter is safe and useful for determining the optimal ablation site in patients with idiopathic VT originating from the RVOT, especially in those without frequent VT or PVC.

Two new elastin cross-links having pyridine skeleton. Implication of ammonia in elastin cross-linking in vivo

Isolation and structure analysis of two amino acids from bovine ligamentum nuchae elastin hydrolysates revealed the presence of pyridine cross-links in elastin. The structures of these amino acids were determined to have 3,4,5- and 2,3,5-trisubstituted pyridine skeletons both with three carboxylic acids and a mass of 396 (C(18)H(28)N(4)0(6)) identified as 4-(4-amino-4-carboxybutyl)-3,5-di-(3-amino-3-carboxypropyl)-pyridine and 2-(4-amino-4-carboxybutyl)-3,5-di-(3-amino-3-carboxypropyl)-pyridine. We have named these pyridine cross-links desmopyridine (DESP) and isodesmopyridine (IDP), respectively. Structure analysis of these pyridine cross-links implied that the formation of these cross-links involved the condensation reaction between ammonia and allysine. The elastin incubated with ammonium chloride showed that DESP and IDP levels increased as the allysine content decreased. DESP and IDP were measured by high pressure liquid chromatography (HPLC) with UV detection and were found in a variety of bovine tissues. The DESP/desmosine (DES) and IDP/isodesmosine (IDE) ratios in aorta elastin were higher than in other tissues. DESP and IDP contents in human aorta elastin were found to be gradually increased with age. The concentration of IDP was significantly elevated in aorta elastin of rat with chronic liver cirrhosis induced by carbon tetrachloride (mean +/- S.D.; 11.1 +/- 0.9 nmol/mg elastin) when compared with normal rats (5.9 +/- 1.5 nmol/mg elastin). Although DESP and IDP are present at only trace concentrations in the tissue elastin, these pyridine cross-links may be useful biomarkers for the aortic elastin damaged by ammonia.

Amine oxidase-like activity of polyphenols. Mechanism and properties

Polyphenols in several oxidation systems gained amine oxidase-like activity, probably due to the formation of the corresponding quinones. In the presence of Cu(II), o- and p-phenolic compounds exhibited amine oxidase-like activity, whereas only the o-phenolic compounds showed the activity in the presence of 1,1-diphenyl-2-picrylhydrazyl radical. The activity was determined by measuring the conversion of benzylamine to benzaldehyde by HPLC. Moreover, gallic acid, chlorogenic acid, and caffeic acid, which are plant polyphenols, converted the lysine residue of bovine serum albumin to alpha-amino-adipic semialdehyde residue, indicating lysyl oxidase-like activity. We also characterized the activity of pyrocatechol, hydroquinone, and pyrogallol in the presence of Cu(II). The oxidative deamination was accelerated at a higher pH, and required O2 and transition metal ions. Furthermore, EDTA markedly inhibited the reaction but not beta-aminopropionitrile, which is a specific inhibitor of lysyl oxidase. Catalase significantly inhibited the oxidation, implying the participation of hydroxyl radical in the reaction, but superoxide dismutase stimulated the oxidation, probably due to its radical formation activity. We discussed the mechanism of the oxidative deamination by polyphenols and the possible significance of the activity for biological systems.

Sympathetic stimulation produces a greater increase in both transmural and spatial dispersion of repolarization in LQT1 than LQT2 forms of congenital long QT syndrome

OBJECTIVES

The study compared the influence of sympathetic stimulation on transmural and spatial dispersion of repolarization between LQT1 and LQT2 forms of congenital long QT sYndrome (LQTS).

BACKGROUND

Cardiac events are more associated with sympathetic stimulation in LQT1 than in LQT2 or LQT3 syndrome. Experimental studies have suggested that the interval between Tpeak and Tend (Tp-e) in the electrocardiogram (ECG) reflects transmural dispersion of repolarization across the ventricular wall.

METHODS

We recorded 87-lead body-surface ECGs before and after epinephrine infusion (0.1 microg/kg/min) in 13 LQT1, 6 LQT2, and 7 control patients. The Q-Tend (QT-e), Q-Tpeak (QT-p), and Tp-e were measured automatically from 87-lead ECGs, corrected by Bazett's method (QTc-e, QTc-p, Tcp-e), and averaged among all 87-leads and among 24-leads, which reflect the potential from the left ventricular free wall. As an index of spatial dispersion of repolarization, the dispersion of QTc-e (QTc-eD) and QTc-p (QTc-pD) were obtained among 87-leads and among 24-leads, and were defined as the interval between the maximum and the minimum of the QTc-e and the QTc-p, respectively.

RESULTS

Epinephrine significantly increased the mean QTc-e but not the mean QTc-p, resulting in a significant increase in the mean Tcp-e in both LQT1 and LQT2, but not in control patients. The epinephrine-induced increases in the mean QTc-e and Tcp-e were larger in LQT1 than in LQT2, and were more pronounced when the averaged data were obtained from 24-leads than from 87-leads. Epinephrine increased the maximum QTc-e but not the minimum QTc-e, producing a significant increase in the QTc-eD in both LQT1 and LQT2 patients, but not in control patients. The increase in the QTc-eD was larger in LQT1 than in LQT2 patients.

CONCLUSIONS

Our data suggest that sympathetic stimulation produces a greater increase in both transmural and spatial dispersion of repolarization in LQT1 than in LQT2 syndrome, and this may explain why LQT1 patients are more sensitive to sympathetic stimulation.

Chemical analysis of transuranium nuclides in the uranium solution of the JCO criticality accident

Atom numbers of 239Np and 239Pu, which had been produced by the neutron capture reaction of 238U in the uranium solution of the JCO criticality accident at Tokai-mura, Japan, were determined precisely by a radiochemical method. It was found that the measured atom ratio of 239Np/239Pu at termination of the criticality depends sensitively on the history of the neutron capture reaction during the accident (about 20-hours continuance). The history was evaluated by comparing the measured value and those calculated by a burnup calculation code. The percentage of the number of the neutron capture reaction at the initial stage of the criticality during 25 min against the total events was determined to be 24±6%.

The role of Purkinje and pre-Purkinje potentials in the reentrant circuit of verapamil-sensitive idiopathic LV tachycardia

Although the mechanism of verapamil-sensitive idiopathic left ventricular tachycardia (ILVT) is usually reentry, the actual reentrant circuit is not clearly understood. This study examined the relationship between the Purkinje potential (PP) and a dull potential preceding PP (pre-PP) during ILVT to elucidate the roles of these potentials in the reentrant circuit of ILVT. Electrophysiological studies and radiofrequency catheter ablation were performed in ten patients (7 men, 3 women, mean age 29 years) who had an ILVT with a right bundle branch block configuration and left-axis deviation. Left ventricular endocardial mapping using an octapolar catheter and entrainment and resetting studies during VT was performed by pacing from the right ventricular outflow tract (RVOT) and each site of the left ventricular mapping catheter. PP and pre-PP were recorded simultaneously during VT in all patients. The earliest PP during VT was recorded at the inferoposterior septum, and PP was activated bidirectionally toward the proximal (basal) and distal (apical) sites along the left posterior fascicle. In contrast, pre-PP was recorded at sites slightly proximal to the earliest PP recording site, and was activated toward the earliest PP site. Pacing from RVOT confirmed manifest entrainment, and the stimulus to pre-PP interval was prolonged with a shorter pacing cycle length. Concealed entrainment was demonstrated by capture of the PPs of the left ventricular mapping catheter in six patients, and the postpacing interval at each PP site was equal to the tachycardia cycle length. The pre-PP was orthodromically activated from the proximal to the distal site during pacing. More rapid pacing also produced delay in activation from PP to pre-PP, indicating slow conduction in ILVT. Catheter ablation was performed at the pre-PP recording site during VT, and was successful in all patients. The reentrant circuit of ILVT could be constructed based on the pre-PP, PP, and slow conduction between the PP and pre-PP. Catheter ablation of ILVT was successful at the pre-PP recording site.

Immortalized gonadotropin-releasing hormone neurons (GT1-7 cells) exhibit synchronous bursts of action potentials

Although it has been assumed that synchronized firing of gonadotropin-releasing hormone (GnRH) neurons is necessary for pulsatile GnRH secretion, there is no clear evidence for this. In the present study we simultaneously recorded spontaneous action potentials from multiple cells. Immortalized GnRH neurons (GT1-7 cells) were cultured on a multi-electrode dish (MED) and action potentials recorded by an extracellular recording method. One to two weeks after the beginning of culture, spontaneous action potentials appeared, exhibiting bursts composed of 5-10 action potentials. Burst activity was intermittent and periodic with mean burst intervals of 13.3 s. Furthermore, burst activity was recorded almost simultaneously from several micro-electrodes, suggesting that electrical activities of GT1-7 cells were synchronized with each other. Periodic bursts were completely and reversibly blocked by 1-5 microM tetrodotoxin, indicating that voltage-dependent Na(+) channels are involved in their generation. gamma-Aminobutyric acid (GABA) given at a 10-microM concentration shortened inter-burst intervals, whereas 10 microM bicuculline lengthened them. Finally, the gap junctional blockers n-octyl alcohol (1 mM) and carbenoxolone (100 microM) reversibly blocked periodic burst activity. The present study provides direct evidence that the electrical activity of GT1-7 cells exhibits synchronous and periodic bursts composed of action potentials. In addition, endogenous GABA is involved in GT1-7 cells in determining burst frequency. Although the precise mechanism of synchronized burst activities needs to be clarified, gap junctional communications among GT1-7 cells are at least partially involved.

Characterization of a model compound for the lysine tyrosylquinone cofactor of lysyl oxidase

We characterized a model compound for the lysine tyrosylquinone (LTQ) cofactor of lysyl oxidase which is one of the mammalian copper-dependent amine oxidases. The model compound, 4-butylamino-5-methyl-o-quinone, was prepared from n-butylamine and 4-methylcatechol by the oxidation with sodium iodate and characterized by spectroscopic analyses. The absorption maximum at 494 nm is consistent with that of lysyl oxidase. The model compound was capable of deaminating benzylamine to benzaldehyde at 37 degrees C in buffered aqueous acetonitrile. The aldehyde production was markedly elevated in the presence of the Cu(II)-EDTA complex but inhibited by free Cu(II). The catalytic cycle was observed at pH 10 in the presence of Cu(II), and the pH activity profile showed a broad optimum at about pH 9.0. In the presence of beta-aminopropionitrile and upon deoxygenation with N2 aldelyde, production was decreased. The important features of the reaction were consistent with the enzymatic reaction.

A study of pretreatment nomograms to predict pathological stage and biochemical recurrence after radical prostatectomy for clinically resectable prostate cancer in Japanese men

BACKGROUND

Accurate pretreatment identification of the risks that prostate cancer has extended beyond the gland and that it will recur would significantly influence practice patterns. Preoperative nomograms to predict such risks have not been developed for the oriental male population.

METHODS

Construction of nomograms to predict preoperatively pathological outcome and early biochemical failure following radical prostatectomy in Japanese males was based on logistic regression analysis, with predicted probabilities and 95% confidence intervals for the final model being obtained by repeating the analysis on 1000 bootstrap samples from the original cohort.

RESULTS

Prostate-specific antigen level, clinical stage and biopsy Gleason score contributed significantly to the prediction of pathological stage and of biochemical failure in the univariate analysis (p < 0.001). Combined use of these three variables predicted these treatment outcomes better than any single variable (p < 0.001). Nomograms combining these three variables to predict final pathological findings and early biochemical failure were then developed. The medians and 95% confidence intervals of the predicted probabilities are presented in the nomograms.

CONCLUSIONS

This information enables clinicians to use their nomograms when counseling Japanese patients, leading to more informed treatment decisions and helping to identify those with a high risk of early biochemical failure. The nomograms may also be used to assure comparability of different treatment modalities in investigational trials.

Biosynthesis of lactosamine in bovine mammary gland

Lactosamine (beta-D-Galp-(1-->4)-D-GlcN) was isolated from bovine milk sampled after intravenous infusion of glucosamine through the jugular vein of a lactating cow. The chemical structure was established by 2D NMR spectroscopy and electrospray ionisation mass spectrometry (ESIMS). Selected ion monitoring liquid chromatography-mass spectrometry (SIMLC-MS) of the perbenzoylated carbohydrate fraction showed the presence of the novel disaccharide in the milk sample after infusion, but not in the control bovine milk sample. The results showed the uptake of glucosamine in bovine mammary gland, and also indicated that a part of glucosamine was metabolised to the product lactosamine.

Effect of sodium channel blockers on ST segment, QRS duration, and corrected QT interval in patients with Brugada syndrome

INTRODUCTION

Brugada syndrome is characterized by an ST segment elevation in leads V1-V3 and a high incidence of ventricular fibrillation (VF). A mutation in a cardiac Na+ channel gene, SCN5A, has been linked to Brugada syndrome, and sodium channel blockers have been shown to be effective in unmasking the syndrome when concealed. The aim of this study was to examine the effects of Na+ channel blockers on ST segment elevation, QRS, corrected QT (QTc) interval, and ventricular arrhythmias in patients with Brugada syndrome.

METHODS AND RESULTS

We examined the effects of three different Na+ channel blockers (flecainide, disopyramide, and mexiletine) on the amplitude of the ST segment 20 msec after the end of QRS (ST20), QRS duration, QTc interval measured from 12-lead ECG, and ventricular arrhythmias in 12 Brugada and 10 control patients. Maximum ST20 observed in the V2 or V3 leads under baseline conditions was greater in the Brugada patients than in control patients, whereas QRS duration and maximum QTc interval were no different between the two groups. Flecainide and disopyramide, but not mexiletine, significantly increased maximum ST20 and QRS duration in both groups, although these effects were much more pronounced in the Brugada patients. The increases in ST20 and QRS duration with flecainide were significantly larger than those with disopyramide. An increase of 0.15 mV in ST20 with flecainide separated the two groups without overlap. Ventricular premature complexes developed only with flecainide in Brugada patients (3/12) displaying a marked ST elevation but not widening of QRS.

CONCLUSION

Our findings suggest that Na+ channel blockers amplify existing I(Na) and possibly other ion channel defects, with a potency inversely proportional to the rate of dissociation of the drug from the Na+ channel, thus causing a prominent elevation of the ST segment and, in some cases, prolongation of QRS duration in patients with Brugada syndrome.

Significant suppressive effect of low-dose temocapril, an ACE inhibitor with biliary excretion, on FGS lesions in hypertensive rats

To investigate how the interruption of the renin-angiotensin system (RAS) and reduction of blood pressure (BP) affect the lesions of chronic focal and segmental glomerulosclerosis (FGS), we studied the effects of high and low doses of angiotensin-converting enzyme inhibitors (temocapril - TEM) a newly developed ACE inhibitor with biliary tract excretion, on the hypertensive model of FGS. A high dose of TEM significantly lowered BP and suppressed both intense proteinuria and glomerular extracapillary lesions including macrophage infiltration. On the other hand, although a low dose of TEM did not significantly lower BP throughout the experimental period, it prevented renal lesions almost in the same manner as high-dose TEM with suppression of c-myc gene expression in glomeruli. These findings suggest that in PAN-induced chronic FGS, the systemic BP elevation could not be the major factor for the progression of renal damage which TEM could prevent without significant lowering of BP.

Mode of onset of ventricular fibrillation in patients with Brugada syndrome detected by implantable cardioverter defibrillator therapy

OBJECTIVES

We sought to demonstrate the mode of spontaneous onset of ventricular fibrillation (VF) in patients with Brugada syndrome.

BACKGROUND

The electrophysiologic mechanisms of VF in Brugada syndrome have not been fully investigated.

METHODS

Nineteen patients (all male, mean age 47 +/- 12 years) with Brugada syndrome were treated with an implantable cardioverter defibrillator (ICD). The implanted devices were capable of storing electrograms during an arrhythmic event. We investigated the mode of spontaneous onset of VF according to the electrocardiographic features during the episode of VF, which were obtained from stored electrograms of ICDs and/or electrocardiographic (ECG) monitoring.

RESULTS

During a follow-up of 34.7 +/- 19.4 months (range 14 to 81 months), 46 episodes of spontaneous VF attacks were documented in 7/19 (37%) patients. The event-free period between ICD implantation and the first spontaneous occurrence of VF was 14.6 +/- 12.1 months (range 3.7 to 27.4 months). We investigated 33/46 episodes of VF, for which electrocardiographic features (10 to 20 s before and during VF) were obtained from ICDs and/or ECG monitoring in five patients. A total of 22/33 episodes of VF were preceded by premature ventricular contractions (PVCs), which were almost identical to the initiating PVCs of VF. Furthermore, in three patients who had multiple VF episodes, VF attacks were always initiated by the same respective PVC. The coupling interval of the initiating PVCs of VF was 388 +/- 28 ms.

CONCLUSIONS

Spontaneous episodes of VF in patients with Brugada syndrome were triggered by specific PVCs. These findings may provide important insights into the pathophysiological mechanisms causing VF in Brugada syndrome.

Chlorination of harman and norharman with sodium hypochlorite and co-mutagenicity of the chlorinated products

Harman and norharman are widely distributed in the environment and consequently contaminate in domestic waste-water. It has been reported that they have co-mutagenic activity in the presence of non- mutagenic aromatic amines such as aniline and o-toluidine with S9 mix. When these beta-carbolines were treated with sodium hypochiorite under mild conditions, chlorinated derivatives were produced. Among them, 6-chloroharman and 6-chloronorharman showed much more potent co-mutagenic activities than harman and norharman in the presence of o-toluidine toward Salmonella typhimurium TA98 with S9 mix. These results suggest that the chlorination of harman and norharman occurs during disinfection at the sewage plant to produce potent co-mutagens that contaminate river water.

Prevention of death of axotomized hypoglossal neurones and promotion of regeneration by chitin grafting

1. Chitin is known to promote skin wound healing. In this study, chitin, prepared from Zuwai crab shell, was used as a bridge between the proximal and distal stumps of cut hypoglossal nerves in shrews. We compared the effects of chitin on the regeneration of transected right hypoglossal nerve axons, with those of porcine dermis, bovine dermal aterocollagen, and autologous nerve bundles. 2. To assess the survival of neurones, the size of neuronal cell body, and number of motoneurones were determined in the absence of any bridged material and in the presence of porcine dermis, bovine dermal aterocollagen, chitin, or autologous nerve bundles as a bridge. 3. Our results revealed a significantly better outcome in chitin and autologous nerve bridged groups; the size of neuronal cell body and number of hypoglossal neurones were higher than in the other groups. Chitin also enhanced the regeneration of neurones; the number of horseradish peroxide positive neurones indicative of repaired axonal processes was significantly higher in chitin and autologous nerve-bridged groups than in other groups. 4. Our results demonstrated that the use of chitin sheet or autograft successfully prevented the death of severed neurones and promoted the regeneration of the lesioned nerve. Although the mechanisms underlying the effects of chitin are still unknown, chitin seems to be a potentially useful biocompatible material for nerve repair and regeneration.

Occlusion of transition metal ions by new adsorbents synthesized from plant polyphenols and animal fibrous proteins

Removing and collecting heavy and rare metal ions from industrial effluents and waste aqueous solutions are important problems. Our previous studies showed that animal fibrous proteins (AFPs) such as hen eggshell membrane, chicken feather (CF), wool, and silk were stable and insoluble proteins and had an excellent ability to bind not only hard (Mn2+ and Fe3+) but also soft (Ag+, Au+, Pd2+, Pt2+, and Hg2+) acids from aqueous solutions. In this study, we synthesized some adsorbents for transition (Cr6+, Mn2+, Co2+, Ni2+, and Cu2+) and heavy (Cd2+) metal ions from AFPs (gelatin, CF, and wool) and plant polyphenols (lignin and tannin) by heating a mixture of AFPs and plant polyphenols under acidic conditions. In batch experiments, pH profile, time dependency, and isotherm analysis were performed to determine binding properties of adsorbents for transition and heavy metal ions. Column experiments were also performed to remove copper ion from aqueous solution. The results showed that the new adsorbents were effective for collecting and removing transition and heavy metal ions from aqueous solutions.

Recovery time dispersion measured from 87-lead body surface potential mapping as a predictor of sustained ventricular tachycardia in patients with idiopathic dilated cardiomyopathy

INTRODUCTION

The clinical usefulness of QT dispersion in 12-lead ECG has been controversial in identifying subjects at risk for sustained ventricular tachycardia (VT) in patients with idiopathic dilated cardiomyopathy (DCM). We hypothesized that increasing the spatial resolution of the ECG improves the accuracy of risk stratification. The purpose of this study was to test the ability of recovery time dispersion measured from 87-lead body surface potential mapping (BSPM) to identify patients at risk for sustained VT in idiopathic DCM.

METHODS AND RESULTS

We obtained 87-lead BSPM and 12-lead ECG in 33 patients with idiopathic DCM (15 patients with a history of sustained VT [VT(+) group] and 18 patients without a history of sustained VT [VT(-) group]) and in 20 normal control subjects. We measured the corrected QT dispersion and corrected recovery time dispersion from 12-lead ECG (QTc-12 dispersion and RTc-12 dispersion, respectively) and 87-lead BSPM (QTc-87 dispersion and RTc-87 dispersion, respectively). Signal-averaged ECG also was recorded in 25 patients. Neither the QTc-12 nor QTc-87 dispersion discriminated between the VT(+) and VT(-) groups patients. The VT(+) group patients had a larger but insignificant RTc-12 dispersion than the VT(-) group patients. In contrast, the RTc-87 dispersion was significantly larger in the VT(+) group patients than in the VT(-) group patients (236 +/- 39 msec vs 184 +/- 28 msec, P < 0.001). Receiver operating curve analysis indicated that the RTc-87 dispersion was as good as late potentials in predicting susceptibility to sustained VT; its sensitivity, specificity, and negative predictive value were 73%, 76%, and 76%, respectively (cutoff value 200 msec). RTc-87 dispersion >200 msec combined with positive late potentials provide high sensitivity (92%) and high negative predictive value (88%) for sustained VT.

CONCLUSION

The RTc-87 dispersion is a useful tool to identify subjects at risk for sustained VT in patients with idiopathic DCM.

[Two cases of primary carcinoma developed in a vesical diverticulum treated with ileal neobladder for total bladder replacement]

Two cases of carcinoma developed in vesical diverticulum were encountered. Both these males, the first, 66-year-old and the second case, 68-year-old gentleman, visited our clinic with a complaint of asymptomatic gross hematuria. Total cystectomy was performed, and an ileal neobladder was constructed for total bladder replacement in both two cases. Pathological examination of the first case revealed transitional cell carcinoma, and the second case showed adenocarcinoma mixed with transitional cell carcinoma. Although primary carcinoma developed in vesical diverticulum was initially reported by Williams in 1883, adenocarcinoma is very rare. The diagnosis is often challenging and the prognosis is dire. Both our cases were successfully treated with total cystectomy and an ileal neobladder was constructed for total bladder replacement. Careful management and aggressive therapy for such patients may make even cure possible.

Expression of the Rh-related glycoprotein (Rh50)

The Rh50 glycoprotein is suspected of being involved in Rh antigen expression. We prepared Rh50 cDNA from a human bone marrow library by polymerase chain reaction and then subcloned this cDNA into various vectors. The vector containing Rh50 cDNA produced a 30-kDa nonglycosylated form of Rh50 in a rabbit reticulocyte lysate system and produced partially glycosylated Rh50 (32 kDa) when microsomes were added to the system. COS-1 cells transiently transfected with the vector containing Rh50 cDNA produced partially glycosylated Rh50 (32 kDa) recognized by a Rh50-specific antibody. Surface expression of Rh50 in K562 cells was also detected by flow cytometry using mouse monoclonal antibody (2D10) specific to Rh50. Partially glycosylated Rh50 (32 kDa) was again isolated from the lysates of K562 cells metabolically labeled with [35S]-methionine or [3H]-mannose using anti-Rh50 antisera. These systems (K562 and COS-1 cells) should prove useful for studying the transport of Rh proteins within the cell and the necessary components needed for Rh antigenicity at the cell surface.

Mesangial factor V expression colocalized with fibrin deposition in IgA nephropathy

BACKGROUND

Factor V in its active form (Va) plays a key role at the termination of the intrinsic coagulation pathway, serving as a membrane-bound cofactor for the conversion of prothrombin to thrombin by factor Xa. Cross-linked fibrin (XFb) is often observed in mesangial areas in active types of human glomerulonephritis. In this study, to clarify contribution of factor V in intramesangial coagulation, mesangial factor V expression and its relationship to mesangial proliferation and fibrin deposition in IgA nephropathy (IgAN) were investigated.

METHODS

Twenty-two patients with IgAN were studied. XFb was detected in renal biopsy specimens using anti-d-dimer antibody combined with plasmin exposure, and factor V was detected with rabbit antibody against human factor V. Double-labeling immunohistochemistry was used to investigate the relationship of the glomerular distribution of factor V to XFb. The relationship of factor V staining to the activity index or XFb deposition was evaluated. The expression of factor V mRNA was assessed by in situ hybridization in relationship to the antigen staining of alpha-smooth muscle actin (alpha-SMA). The ultrastructural distribution of factor V in glomeruli was studied by immunoelectron microscopy.

RESULTS

XFb and factor V were observed in the mesangium and along capillary loops in seven and nine specimens, respectively. Factor V had intense, frequent expression in the proliferating and necrotizing areas, showing a significant relationship to XFb (P < 0.05). Furthermore, XFb deposition and factor V expression were markedly correlated with disease activity (P = 0.005 and P = 0.008, respectively). By double-labeling experiments, XFb and factor V were often seen colocalized in mesangial areas of the glomeruli, which showed necrotizing lesions and/or intense cellular proliferation. By in situ hybridization, factor V mRNA was detected mainly in the mesangial cells, which were positive for alpha-SMA, and partly in the endothelial cells. By immunoelectron microscopy, factor V presence was confirmed in the mesangium and endothelium.

CONCLUSION

The present findings suggest that factor V is strongly expressed in mesangial cells in active IgAN accompanied with mesangial proliferation and may exert procoagulant activity, leading to intramesangial coagulation.

Clinical characteristics of patients with spontaneous or inducible ventricular fibrillation without apparent heart disease presenting with J wave and ST segment elevation in inferior leads

INTRODUCTION

The clinical characteristics of three patients with spontaneous or inducible ventricular fibrillation (VF) without apparent heart disease, who presented with J wave and ST segment elevation in inferior leads, are described.

METHODS AND RESULTS

All patients were male and experienced syncope. Their symptoms occurred at night or early in the morning. Holter ECG revealed infrequent premature ventricular complexes. Injection with disopyramide 2 mg/kg augmented ST segment elevation.

CONCLUSION

These characteristics were very similar to those of patients with Brugada syndrome. These three patients with these specific features might have a variant of Brugada syndrome.

Body surface distribution and response to drugs of ST segment elevation in Brugada syndrome: clinical implication of eighty-seven-lead body surface potential mapping and its application to twelve-lead electrocardiograms

INTRODUCTION

Body surface distribution and magnitude of ST segment elevation and their reflection in 12-lead ECGs have not been clarified in Brugada syndrome.

METHODS AND RESULTS

Eighty-seven-lead body surface potential mapping and 12-lead ECGs were recorded simultaneously in 25 patients with Brugada syndrome and 40 control patients. The amplitude of the ST segment 20 msec after the end of QRS (ST20) was measured from all 87 leads, and an ST isopotential map was constructed. The maximum ST elevation (maxST20) was distributed in an area of the right ventricular outflow tract in all Brugada patients, and it was larger than that in control patients (0.37 +/- 0.13 vs 0.12 +/- 0.04 mV; P < 0.0005). The maximum was observed on the level of the parasternal fourth intercostal space, on which the V1 and V2 leads of the standard 12-lead ECG were located, in 18 of the 25 Brugada patients in whom typical coved- or saddleback-type ST elevation was seen in leads V1 and V2. The maximum was located on the second intercostal space in the remaining seven Brugada patients in whom only a mild saddleback-type ST elevation was seen in leads V1 and V2 of the 12-lead ECG. Typical ST segment elevation was recognized in leads V1 and V2, which were recorded on the second or third intercostal space. ST elevation in Brugada patients was dramatically normalized by isoproterenol, a beta-adrenergic agonist (maxST20 = 0.17 +/- 0.08 mV; P < 0.0005 vs control conditions), and accentuated by disopyramide, an Na+ channel blocker (maxST20 = 0.50 +/- 0.15 mV; P < 0.0005 vs control conditions), without any change in the location of the maxST20.

CONCLUSION

Our data indicate that recordings of leads V1-V3 of the 12-lead ECG on the parasternal second or third intercostal space would be helpful in diagnosing suspected patients with Brugada syndrome. The data suggest that Na+ channel blockers are capable of accentuating ST elevation in leads V1-V3.

Bisphenol derivative of allysine for high-performance liquid chromatographic analysis of allysine residue of proteins

Allysine is the most important precursor of physiologically essential cross-links formation in collagen and elastin and is formed by enzymatic oxidative deamination of lysine residues. Because it is a highly reactive aldehyde, many cross-linking amino acid residues may arise from its reaction with other allysine residues or lysine or even histidine residues. We purified and isolated an allysine bisphenol derivative, 1-amino-1-carboxy-5,5-bis-p-hydroxyphenylpentane (ACPP), from the reaction products of phenol and allysine residue of bovine ligamentum nuchae by acid hydrolysis in 6 M HCl. The structure of ACPP was verified by UV, fast atom bombardment-MS, 1H- and 13C-nuclear magnetic resonance spectroscopies. The optimal reaction condition for ACPP synthesis accompanied by hydrolysis of such proteins was investigated and an ion-paired high-performance liquid chromatographic method for determination of allysine as ACPP was also developed.