bluuebunny/crossref_metadata_2025 huggingface dataset:
Gamma irradiation as a quarantine treatment for apples infested by codling moth (Lep., Tortricidae)
Authors: Mansour M.
Published: December 2004

Abstract: Effects of gamma radiation on the fifth instar codling moth, Cydia pomonella (L.), larvae were examined. Mature larvae were exposed to a series of gamma radiation doses ranging from 50 to 250 Gy and survival to pupae and adults was examined. The results showed that pupation and adult emergence decreased with increasing radiation dose. The results also showed that diapausing larvae were more sensitive to irradiation treatment than non‐diapausing larvae, and females were more sensitive than males. A dose of 150 Gy reduced adult emergence to less than 2% in non‐diapausing larvae, while a dose of 200 Gy completely prevented it. Furthermore, none of the emerging moths exposed to a dose of 150 Gy were females; at 100 Gy dose, the percentage of females was less than 14%. Irradiating larvae in apple fruit in a small‐scale laboratory experiment produced similar results. Tests in which >100 000 larvae (in the fifth instar) were irradiated in an artificial rearing medium with a dose of 200 Gy resulted in no adult emergence. Similar results were also obtained when >32 000 larvae in the same stage were exposed in apple fruit to the same dose. The results indicate that the use of ionizing radiation as a quarantine treatment for codling moth infested fruits is feasible and requires a relatively low dose.
Effect of temperature on life table parameters of Podisus nigrispinus (Het., Pentatomidae) fed with Alabama argillacea (Lep., Noctuidae) larvae
Authors: Medeiros R. S. , Ramalho F. S. , Zanuncio J. C. , Serrão J. E.
Published: December 2004

Abstract: The influence of temperature on life table parameters of Podisus nigrispinus (Dallas) (Het., Pentatomidae) fed with Alabama argillacea (Hübner) (Lep., Noctuidae) larvae was studied. This predator was kept at constant temperatures of 20, 23, 25, 28, 30 and 33±0.2°C, at relative humidity of 60±10% and photoperiod of L : D 14 : 10. Gross (GRR) and net (R0) reproductive rates of P. nigrispinus ranged from 1.6 to 366.6 and from 0.02 to 189.5 females/female at temperatures of 33 and 28°C, respectively; generation time (T ) ranged from 33.3 (33°C) to 85.5 (20°C) days; doubling time (D) from 0.82 (33°C) to 17.8 (20°C) days; intrinsic rate of increase (rm) from −0.13 (33°C) to 0.12 (28°C) per day; and the finite rate of increase (λ) from 0.88 (33°C) to 1.12 (28°C) females/female added to the population per day. The ideal age to release P. nigrispinus should be when this predator presents higher reproductive values (VRx); that is, its adults are about 7 days old, independent of prevailing temperature. Population growth of P. nigrispinus was affected by temperature with maximum numerical response between 28 and 30°C. The negative population growth shown at 33°C may not occur in natural conditions due to milder microclimate in the cotton agroecosystem and due to oscillations of temperature in the course of the day.
Screening of molecular markers for NPV resistance in Bombyx mori L. (Lep., Bombycidae)
Authors: Yao Q. , Li M. W. , Wang Y. , Wang W. B. , Lu J. , Dong Y. , Chen K. P.
Published: December 2004

Abstract: Silkworm (Bombyx mori L.) is one of the important economic insects. Silkworm rearing and silk industry plays an important role in China, India and other developing countries. In the long history of sericultural practice, introduction of silkworm strains with high resistance to diseases has greatly improved cocoon and silk quality and productivity. However, current silkworm breeding is mainly based on traditional method that involves high input of time and labour. In order to increase the selection efficiency and accuracy for future silkworm breeding, it is necessary to establish a molecular marker‐assisted selection system. In our study, three silkworm near isogenic lines that had different resistance to nuclear polyhedrosis virus (NPV) were established by means of different hybridization methods. A total of 150 random amplified polymorphic DNA (RAPD) random primers were used to screen molecular markers. Among them, two molecular markers OPA‐18700 and OPY‐11400 were found linked to major genes resistant and susceptible to NPV, respectively. Validity of the molecular markers was proved in F2 populations.
Scoliopteryx libatrix (L.) (Lep., Noctuidae) male reaction to the synthetic main sex pheromone component and its isomers – wind tunnel and field investigations
Authors: Toshova T. , Subchev M. , Plass E. , Francke W.
Published: December 2004

Abstract: The four stereoisomers of 6,13‐methylheneicosene were tested with Scoliopteryx libatrix (L.) males in a wind tunnel. The most active isomer was (Z6,S13)‐methylheneicosene which had been identified as the main sex pheromone component of the species. Some medium activity was found for (Z6,R13)‐ and (E6,S13)‐, while the (E6,R13)‐stereoisomer showed the lowest activity. These results were confirmed in field tests with sticky traps. Monitoring of S. libatrix at two sites showed that the flight of the insects started at the end of March to the beginning of April and lasted till August to the beginning of September. It was concluded that the males of the second generation were not attracted by the pheromone.
Interactions between parasitoids and fungal disease of a forest lepidopteran
Authors: Hicks B. J. , Watt A. D.
Published: December 2004

The larvae of the pine beauty moth, Panolis flammea, were severely affected by a fungal epizootic during 1998. The rate of parasitism of field collected larvae was much lower in 1998 than was recorded 10 years earlier in the same forests. This occurred even when host densities were greater. The parasitism rate declined further in the third year of the study as host numbers increased. Data on parasitoid abundance indicated that parasitoids were out‐competed by the fungal disease for pine beauty moth hosts. Parasitoids of the pine beauty moth are polyphagous which are generally not density‐dependent on one host. However, in this case, the abundance of parasitoids appeared to be dependent on the density of this insect mainly because the pine beauty moth is the most abundant caterpillar in Scottish lodgepole pine plantations.
Alcohol and drug treatment for women: Clinicians’ beliefs and practice
Authors: Cowan Lois , Deering Daryle , Crowe Marie , Sellman Doug , Futterman‐Collier Ann , Adamson Simon
Published: December 2004

ABSTRACT

The present paper reports on the results of a telephone survey of 217 alcohol and drug treatment clinicians on their beliefs and practice, in relation to service provision for women. Nurses comprised the second largest professional group surveyed. Seventy‐eight percent of clinicians believed that women's treatment needs differed from men's and 74% reported a range of approaches and interventions, such as assisting with parenting issues and referral to women‐only programmes. Several differences emerged in relation to approaches and interventions used, depending on clinician gender, work setting and proportion of women on clinicians’ caseload. Implications for mental health nursing include the need to more systematically incorporate gender‐based treatment needs into practice and undergraduate and postgraduate education and training programmes.
Preventive effects of urinary bladder tumors induced by N‐butyl‐N‐(4‐hydroxybutyl)‐nitrosamine in rat by green tea leaves
Authors: Sato Daisuke , Matsushima Masahiro
Published: December 2004

Background: Recently, the anticarcinogenic effects of green tea have been studied in sites other than the urinary tract. Although the incidence of bladder cancer has increased, responses to therapy have been limited. The present work examined the preventive effects of green tea against bladder tumors induced in rats by the carcinogen, N‐butyl‐N‐(4‐hydroxybutyl)‐nitrosamine(BBN).

Methods: From week 5 to week 9, all the groups were exposed to 0.05% BBN in the drinking water for 5 weeks. Rats were divided into four groups. Group 1 was fed a CE‐2 diet and tap water for the entire experimental period and served as the control group. Group 2 was fed the green tea leaves after carcinogen exposure. Groups 3 and 4 received green tea leaves before carcinogen exposure. All rats were killed and examined at 44 weeks.

Results: Green tea leaves prevented the growth of BBN‐induced urinary bladder tumors when given before the carcinogen.

Conclusion: Green tea may inhibit tumor initiation in the bladder.
Simple correction of ureteral stomal stenosis for cutaneous ureterostomy
Authors: Hiratsuka Yoshiharu , Ishii Tatsu , Taira Hiroshi , Okadome Aya
Published: December 2004

Cutaneous ureterostomy is a simple procedure to perform, but has some morbidity owing to stomal stenosis. We describe a new and simple technique applied to the stomal stenosis for cutaneous ureterostomy.
Value of selective upper tract cytology for recognition of upper tract tumors after treatment of superficial bladder cancer
Authors: GÖǦÜŞ ÇAǦATAY , BALTACI SÜMER , ŞAHİNLİ SAVAŞ , TÜRKÖLMEZ KADİR , BEDÜK YAŞAR , GÖǦÜŞ ORHAN
Published: December 2004

Background: The value of selective upper urinary tract (UT) cytology in patients who are asymptomatic and tumor free at control cystoscopy after being treated for superficial bladder carcinoma has not been studied. The present study was performed to evaluate the value of selective UT cytology in patients who are tumor free at control cystoscopy after being treated for superficial bladder cancer.

Methods: Forty‐seven consecutive patients who had undergone definitive surgical treatment for superficial bladder cancer at least 24 months prior and were tumor free at control cystoscopy were evaluated with bladder wash for cytology as well as selective UT urine cytology by catheterization of both ureteral orifices. Of the 47 patients, disease was stage Ta in 30 (63.8%), T1 in 15 (31.9%) and Ta/Tcis in 2 (4.3%). Primary tumor was unifocal in 24 (51.1%) and multifocal in 23 (48.9%) patients. The time elapsed from the initial diagnosis to the last evaluation ranged from 2 to 21 years (mean 5.39).

Results: UT cytology was positive in 2 cases. Although, excretory urography (IVP) revealed mild pelvicalicectasis in 1 of these 2 patients, ureterorenoscopy (URS) revealed no abnormality. In the other patient with normal IVP and retrograde pyelography (RGP), URS revealed a ureteral tumor 5 mm in diameter. Although the UT cytology was normal in the remaining 45 patients, IVP revealed right hydronephrosis in 1 patient and URS revealed multiple ureteral tumors.

Conclusion: Given the normal appearance of the UT, it is highly unlikely that these patients have tumor in the UT. Thus, during the follow‐up of patients with superficial bladder cancer, it is not useful to perform UT select cytology in the absence of any identifiable filling defects in the upper urinary tract.
Adenocarcinoma of the female urethral diverticulum treated by multimodality therapy
Authors: AWAKURA YASUO , NONOMURA MITSUO , ITOH NORIYUKI , MAENO ATSUSHI , FUKUYAMA TAKUO
Published: December 2004

A 75‐year‐old female presented with a 7‐month history of intermittent macrohematuria and urinary retention. Physical examination revealed a firm, round mass on the anterior vaginal wall. The diagnosis by urethroscopy and radiological evaluation was localized urethral diverticular tumor. Pathological examination of the biopsy specimen revealed adenocarcinoma. The patient received two courses of intra‐arterial and systemic chemotherapy using cisplatin, 5‐fluorouracil and leucovorin, followed by radiation to the urethra. The tumor shrunk markedly after chemotherapy. The patient underwent total urethrectomy and vesicostomy. Two years after the operation, she had no evidence of recurrence. Adenocarcinoma of the female urethral diverticulum is rare and has been treated by surgery and/or radiation. The present case is the first case of it being treated by multimodality therapy including chemotherapy.
Intraoperative electrical stimulation of cavernous nerves with monitoring of intracorporeal pressure to confirm nerve sparing during radical prostatectomy: Early clinical results
Authors: TERADA NAOKI , ARAI YOICHI , KUROKAWA KOHEI , OHARA HIROKI , ICHIOKA KENTARO , MATUI YOSHIYUKI , YOSHIMURA KOJI , YAMANAKA HIDETOSHI , TERAI AKITO
Published: December 2004

Background: We performed intraoperative cavernous nerve stimulation with an intracavernous pressure (ICP) monitoring system to confirm nerve sparing during radical pelvic surgery and assessed the results.

Methods: Nineteen cases of radical prostatectomy and three of radical cystoprostatectomy were examined. Electrical stimulation of the site where the neurovascular bundle (NVB) was determined to run was performed and changes in ICP were measured before and after prostate removal.

Results: Of the 22 patients, bilateral NVBs were preserved in six patients while unilateral NVB was preserved in 16. Before dissection, all NVBs examined exhibited positive responses (ICP changes of>5 mmHg) to nerve stimulation. After removal of the prostate, positive responses were observed in 22 (79%) of 28 macroanatomically preserved NVBs. Of 16 sides on which the NVB was not preserved, there were positive responses in five (31%). In these patients, some nerve fibers were macroscopically observed lateral to the original site of NVB. Finally, bilateral or unilateral nerve sparing was confirmed electrophysiologically in 20 (91%) of the 22 patients.

Conclusion: Intraoperative stimulation of the NVB while monitoring ICP changes is a simple and reliable method of accurately evaluating the preservation of cavernous nerves. This system may provide further insight into the mechanism of postoperative erectile dysfunction.
Microscopic colitis: an underdiagnosed cause of chronic diarrhoea − the clue is in the biopsies
Authors: Pokorny C. S. , Selby W. S.
Published: December 2004

Microscopic forms of colitis (collagenous colitis and lymphocytic colitis) are uncommon but important causes of chronic diarrhoea that are often overlooked. The clinical features of these disorders are similar, and they are more common in middle‐aged females, although the female predominance is greater in colla­genous colitis. Although their cause is unclear, both are associated with a variety of autoimmune diseases. Colonoscopy and barium enema are typically normal, so that the diagnosis depends on the demonstration of characteristic changes on histopathological examination of colorectal biopsies. These should be taken in all patients undergoing colonoscopy for the investigation of chronic diarrhoea. There are no large controlled trials of therapy available. Treatment is empirical, generally using the same agents as for inflammatory bowel ­disease. Assessment of therapy is also difficult as spontan­eous remissions occur often. (Intern Med J 2003; 33: 305−309)
Treatment of recurrent aspiration pneumonia in end‐stage dementia: preferences and choices of a group of elderly nursing home residents
Authors: Low J. A. , Chan D. K. Y. , Hung W. T. , Chye R.
Published: December 2004

Abstract

Background:  Clinicians are often faced with the dilemma of how best to manage patients with advanced dementia who present to the hospital with repeated episodes of aspiration pneumonia. Rarely, if at all, are the opinions of the group that is most likely to be directly affected, that is the older nursing home resident, sought. This study seeks to fill that gap.

Aims:  To study the choices and preferences of a group of elderly nursing home residents in the treatment of recurrent aspiration pneumonia on a background of severe disability from end‐stage dementia.

Methods:  A descriptive cross‐sectional interview study using a hypothetical scenario carried out in six nursing homes within eastern Sydney, from June to August 2000. Views and attitudes towards hospitali­zation, antibiotic use, tube feeding and other treatment measures, given a situation of recurrent aspiration pneumonia and end‐stage dementia, were obtained.

Results:  Fifty‐two elderly nursing home residents who were cognitively intact and not depressed were interviewed. Most of the subjects would prefer further hospital admissions (61.5%, P < 0.1) and would choose to have antibiotic treatment (73.1%, P < 0.001). Slightly more than half would not agree to artificial ventilation. Sixty‐nine percent of the respondents would not agree to feeding via a nasogastric tube (P < 0.05) and 71% would not agree to a feeding gastrostomy (P < 0.001). Most would agree to a modified diet (75%, P < 0.0001) and to continue oral feeding despite the attendant risk of re‐aspiration (59.6%, P < 0.01).

Conclusions:  The participants generally preferred to be treated in a hospital setting given the scenario. Most disagreed with the use of artificial feeding. (Intern Med J 2003; 33: 345−349)
International comparison of quality indicators in United States, Icelandic and Canadian nursing facilities
Authors: Jensdóttir A. B. , Rantz M. , Hjaltadóttir I. , Guđmundsdòttir H. , Rook M. , Grando V.
Published: December 2004

Aim: To discuss the results of a comparison using minimum data set (MDS)‐based quality indicators (QIs) for residents in nursing facilities in three countries (Iceland; Ontario, Canada; and Missouri, United States) together with implications regarding nursing practices and resident outcomes in these countries. Method: Data were extracted from databases in each country for four consecutive quarterly periods during 1997 and 1998. All facilities investigated had the required consecutive quarterly data. Analytical techniques were matched to measure resident outcomes using the same MDS‐based QIs in the three countries. Results: Similarities among the three countries included the use of nine or more multiple medications, weight loss, urinary tract infection, dehydration, and behavioural symptoms that affect others. Differences among the three countries included bowel and bladder incontinence, indwelling catheter use, fecal impaction, tube feeding use, development of pressure ulcers, bedridden residents, physical restraint use, depression without receiving antidepressant therapy, residents with depression, use of anti‐anxiety or hypnotic drugs, use of anti‐psychotic drugs in the absence of psychotic and related conditions, residents spending little or no time in activities, and falls. Conclusions: Comparisons highlighted differences in clinical practices among countries, which may account for differences in resident outcomes. Learning from each other's best practices can improve the quality of care for older people in nursing homes in many countries.
Circumferential Ultrasound Ablation for Pulmonary Vein Isolation: Analysis of Acute and Chronic Failures
Authors: SALIBA WALID , WILBER DAVID , PACKER DOUGLAS , MARROUCHE NASSIR , SCHWEIKERT ROBERT , PISANO ENNIO , SHEWCHIK JEANNIE , BASH DIANNA , FANELLI RAFFAELE , POTENZA DOMENICO , SANTARELLI PIETRO , TCHOU PATRICK , NATALE ANDREA
Published: December 2004

Circumferential Ultrasound Ablation for PV Isolation.
Introduction: In patients undergoing circumferential isolation of the pulmonary veins with an ultrasound ablation system, we analyzed the temperatures achieved while delivering circumferential ostial lesions in the pulmonary veins. We also reviewed the angiograms obtained during the procedure and identified anatomic variants that could be responsible for ineffective lesion formation.

Methods and Results: During the early clinical use in 33 patients, a total of 85 veins were ablated. A mean of 16.9 ± 12.3 ablations were delivered per patient, and a mean of 6.7 ablations per vein were applied. Entry block was assessed by placing a deflectable octapolar or a circular catheter in the vein. The following anatomic characteristics and technical limitations were identified as possible reasons for ineffective energy delivery: (1) funnel‐shaped ostium; (2) ostial diameter larger than the balloon diameter; (3) inability to deliver the catheter to the right inferior or other vein ostia; (4) ostial instability; (5) early branching of the vein; and (6) eccentric position of the ultrasound transducer in the vein. In patients with recurrence of atrial fibrillation, 40% of the ostial lesions reached a temperature > 60°C. However, in patients cured by the ablation, 64% of the ostial lesions reached a temperature > 60°C (P < 0.06). At least 12 of the 20 chronic recurrences could have been related to technical limitations of the first system. Duration of atrial fibrillation and eccentric deployment of the ultrasound transducer were more frequent in patients with recurrence of arrhythmias at follow‐up.

Conclusion: Ostial anatomy of the veins may affect delivery of ultrasound energy to achieve circumferential lesions. Energy delivery at the ostium with a temperature > 60°C may be important to maximize success. Reconfiguration of the system to overcome the shortcomings identified in the initial experience could increase its performance.
Prospective Randomized Comparison of Closed Cooled‐Tip versus 8‐mm‐Tip Catheters for Radiofrequency Ablation of Typical Atrial Flutter
Authors: SCHREIECK JUERGEN , ZRENNER BERNHARD , KUMPMANN JOHANNA , NDREPEPA GJIN , SCHNEIDER MICHAEL A.E. , DEISENHOFER ISABEL , SCHMITT CLAUS
Published: December 2004

Cooled‐Tip vs 8‐mm‐Tip Ablation of Atrial Flutter.
Introduction: Cooled‐tip and 8‐mm‐tip catheters have been found to be more effective than conventional 4‐mm‐tip catheters for radiofrequency (RF) ablation of common atrial flutter. The aim of this study was to compare the efficacy and safety of cooled‐tip and 8‐mm‐tip catheters for flutter ablation in a randomized, prospective study.

Methods and Results: In 100 consecutive patients referred for ablation of common atrial flutter, cavotricuspid ablation was performed with a closed cooled‐tip catheter (n = 50) or an 8‐mm‐tip ablation catheter (n = 50). RF current was applied for 60 to 120 seconds at powers of 40 to 50 W with the closed cooled‐tip catheter and in a temperature‐controlled mode (65°C/70 W) with the 8‐mm‐tip catheter. The endpoint was achievement of a bidirectional isthmus conduction block. Cross‐over was performed after 15 unsuccessful RF applications for each of the catheters. Complete bidirectional isthmus block was achieved in 99% of patients. Cross‐over was performed in 11 patients after primary use of the cooled‐tip catheter and in 9 patients after primary ablation with the 8‐mm‐tip catheter. No significant differences were found in the procedure parameters, such as overall RF applications (12.4 ± 11.3 vs 12.9 ± 8.6), ablation duration (42 ± 43 min vs 39 ± 27 min), and fluoroscopy time (17.0 ± 18.7 min vs 15.7 ± 10.7 min). In a mean follow‐up of 8.3 months, 1 patient in the cooled‐tip group and 3 patients in the 8‐mm‐tip group had recurrence of common atrial flutter.

Conclusion: Use of the closed cooled‐tip ablation catheter and the 8‐mm‐tip catheter have equal and high efficacy for RF ablation of common atrial flutter.
Effect of Electrical and Structural Remodeling on Spatiotemporal Organization in Acute and Persistent Atrial Fibrillation
Authors: AKAR JOSEPH G. , EVERETT THOMAS H. , KOK LAI‐CHOW , MOORMAN J. RANDALL , HAINES DAVID E.
Published: December 2004

Spatiotemporal Organization in Atrial Fibrillation.
Introduction: Atrial fibrillation (AF) may originate from discrete sites of periodic activity. We studied the effect of structural and electrical remodeling on spatiotemporal organization in acute and persistent AF.

Methods and Results: Atrial effective refractory periods (AERPs) were recorded from five different sites at baseline and after pacing in acute AF (n = 8 dogs) and persistent AF (n = 8). Four persistent AF dogs subsequently were cardioverted to sinus rhythm to allow AERP recovery. Periodicity was quantified by calculating power spectra on left atrial electrograms obtained from a 64‐electrode basket catheter. Left atrial size was measured by intracardiac echocardiography and structural changes were assessed by electron microscopy. Mean AERPs decreased after pacing in acute (128 ± 16 msec to 108 ± 29 msec, P < 0.001) and persistent AF (135 ± 16 msec to 104 ± 24 msec, P < 0.0001). AERP recovery was established after 7 days of sinus rhythm. Structural changes were mild in acute AF, severe in persistent AF, and remained severe after AERP recovery. A single dominant frequency was identified in 94% of acute AF bipoles, 57% in persistent AF, and 76% after AERP recovery. Average correlation coefficient was 0.82 among acute AF bipoles, 0.63 in persistent AF, and 0.73 after AERP recovery.

Conclusion: Transition from acute to persistent AF is associated with loss of spatiotemporal organization. A single dominant frequency recruits the majority of the left atrium in acute AF. Persistent AF, however, is associated with structural remodeling and dominant frequency dispersion. Recovery of refractoriness only partially restores spatiotemporal organization, indicating a major role for structural remodeling in the maintenance of persistent AF.
Left Atrial Flutter After Radiofrequency Catheter Ablation of Focal Atrial Fibrillation
Authors: VILLACASTÍN JULIÁN , PÉREZ‐CASTELLANO NICASIO , MORENO JAVIER , GONZÁLEZ ROSA
Published: December 2004

We report an arrhythmic complication in two patients in whom a procedure directed at isolating one or two pulmonary veins had been performed. The complication was related to pulmonary vein disconnection scars after ablation. Both patients developed new clinical tachycardia (atypical atrial flutter) secondary to a reentrant phenomena in the vicinity of a previously ablated pulmonary vein.
(J Cardiovasc Electrophysiol, Vol. 14, pp. 417‐421, April 2003)
Development of the Cardiac Conduction System as Delineated by minK‐lacZ
Authors: KONDO RICHARD P. , ANDERSON ROBERT H. , KUPERSHMIDT SABINA , RODEN DAN M. , EVANS SYLVIA M.
Published: December 2004

Introduction: Due to the lack of good molecular markers, for decades the morphogenetic origin of the cardiac conduction system has been a matter of debate. More recently, the spatial expression of minK‐lacZ in the adult mouse heart has been shown, for the larger part, to be coincident with the conduction tissues.

Methods and Results: To trace the embryonic development of this system, we performed an analysis of the expression of this construct throughout early cardiac development. Expression was first seen at the eighth embryonic day. Subsequently, discrete rings were found at the sinuatrial, atrioventricular, interventricular, and ventriculoarterial junctions. With time, the expression became restricted to boundary regions of the heart, such as the hinges of the leaflets of the pulmonary and aortic valves, the atrioventricular rings, and the venous valves, as well as becoming incorporated into the definitive conduction tissues themselves. In the postnatal heart, the areas retaining minK‐lacZ positivity outside of the definitive conduction tissues are known to be the site of origin of abnormal cardiac rhythms, suggesting that ectopic foci may derive from tissues that share a common developmental pathway with the definitive conduction system.

Conclusion: Our findings suggest that the boundary regions between compartments, along with the atrioventricular conduction axis, share a common developmental pathway.
(J Cardiovasc Electrophysiol, Vol. 14, pp. 383‐391, April 2003)
P Wave Polarities of an Arrhythmogenic Focus in Patients with Paroxysmal Atrial Fibrillation Originating from Superior Vena Cava or Right Superior Pulmonary Vein
Authors: KUO JEN‐YUAN , TAI CHING‐TAI , TSAO HSUAN‐MING , HSIEH MING‐HSIUNG , TSAI CHIN‐FENG , LIN WEI‐SHIANG , LIN YUNG‐KUO , DING YU‐AN , JIA‐YIN HOU CHARLES , TSAI CHENG‐HO , CHEN SHIH‐ANN
Published: December 2004

Introduction: The superior vena cava (SVC) and right superior pulmonary vein (RSPV) are anatomically close structures. Using 12‐lead ECG may facilitate identification of ectopic foci from SVC or RSPV. The aim of this study was to assess whether P wave polarity on surface ECG is helpful in distinguishing an arrhythmogenic focus of paroxysmal atrial fibrillation (AF) from SVC or RSPV.

Methods and Results: Thirty‐four patients with paroxysmal AF from the SVC (group I: 17 patients, 10 men and 7 women; mean age

57 ± 12 years

) or RSPV (group II: 17 patients, 15 men and 2 women, mean age

62 ± 14 years

) underwent electrophysiologic study and radiofrequency (RF) catheter ablation. All of the AF foci were confirmed by successful ablation. P wave polarities on surface ECG inferior leads were positive during sinus rhythm and ectopic beats in both groups. Leads I, aVR, aVL, and V1 were further analyzed. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) in predicting an arrhythmogenic focus of AF from SVC or RSPV were provided. P wave polarity in lead aVR was negative in all 34 patients. P wave polarity in lead V1 was positive in 47.1% of SVC ectopy but positive in all RSPV ectopy. The combination of a biphasic or isoelectric P wave polarity in lead V1 or a biphasic P wave polarity in lead aVL had a sensitivity of 71%, specificity of 82%, PPV of 80%, and NPV of 74% in predicting an arrhythmogenic focus of AF from SVC.

Conclusion: P wave polarity in leads V1 and aVL may predict an arrhythmogenic focus of AF from SVC or RSPV. (J Cardiovasc Electrophysiol, Vol. 14, pp. 350‐357, April 2003)
Accessory Pathway in Left Inferoposterior Diverticulum Masquerading as Left Posterior Pathway Due to Conduction Over Coronary Sinus to Left Atrium Connection
Authors: HUSSIN AZLAN , SANDERS PRASHANTHAN , KISTLER PETER M. , SPARKS PAUL B. , KALMAN JONATHAN M.
Published: December 2004

We report the case of an accessory pathway in a left inferoposterior diverticulum. The pathway masqueraded as a true left lateral pathway due to the direction of activation over a coronary sinus to left atrium connection. The patient had undergone four prior failed ablation attempts at other institutions using both a transseptal and retrograde approach.
(J Cardiovasc Electrophysiol, Vol. 14, pp. 403‐406, April 2003)
Additional Gene Variants Reduce Effectiveness of Beta‐Blockers in the LQT1 Form of Long QT Syndrome
Authors: KOBORI ATSUSHI , SARAI NOBUAKI , SHIMIZU WATARU , NAKAMURA YOSHIHIDE , MURAKAMI YOSUKE , MAKIYAMA TAKERU , OHNO SEIKO , TAKENAKA KOTOE , NINOMIYA TOMONORI , FUJIWARA YUICHIRO , MATSUOKA SATOSHI , TAKANO MAKOTO , NOMA AKINORI , KITA TORU , HORIE MINORU
Published: December 2004

Introduction: Beta‐blockers are widely used to prevent the lethal cardiac events associated with the long QT syndrome (LQTS), especially in KCNQ1‐related LQTS (LQT1) patients. Some LQT1 patients, however, are refractory to this therapy.

Methods and Results: Eighteen symptomatic LQTS patients (12 families) were genetically diagnosed as having heterozygous KCNQ1 variants and received beta‐blocker therapy. Cardiac events recurred in 4 members (3 families) despite continued therapy during mean follow‐up of 70 months. Three of these patients (2 families) had the same mutation [A341V (KCNQ1)]; and the other had R243H (KCNQ1). The latter patient took aprindine, which seemed to be responsible for the event. By functional assay using a heterologous mammalian expression system, we found that A341V (KCNQ1) is a loss‐of‐function type mutation (not dominant negative). Further genetic screening revealed that one A341V (KCNQ1) family cosegregated with S706C (KCNH2) and another with G144S (KCNJ2). Functional assay of the S706C (KCNH2) mutation was found to reduce the current density of expressed heterozygous KCNH2 channels with a positive shift (+8 mV) of the activation curve. Action potential simulation study was conducted based on the KYOTO model to estimate the influence of additional gene modifiers. In both models mimicking LQT1 plus 2 and LQT1 plus 7, the incidence of early afterdepolarization was increased compared with the LQT1 model under the setting of beta‐adrenergic stimulation.

Conclusion: Multiple mutations in different LQTS‐related genes may modify clinical characteristics. Expanded gene survey may be required in LQT1 patients who are resistant to beta‐blocker therapy. (J Cardiovasc Electrophysiol, Vol. 15, pp. 190‐199, February 2004)
Relationship Between Connexins and Atrial Activation During Human Atrial Fibrillation
Authors: KANAGARATNAM PRAPA , CHERIAN ASHOK , STANBRIDGE REX D.L. , GLENVILLE BRIAN , SEVERS NICHOLAS J. , PETERS NICHOLAS S.
Published: December 2004

Introduction: Gap junctional connexin proteins (connexin40 [Cx40], connexin43 [Cx43]) are a determinant of myocardial conduction and are implicated in the development of atrial fibrillation (AF). We hypothesized that atrial activation pattern during AF is related to connexin expression and that this relationship is altered by AF‐induced remodeling in the fibrillating atria of chronic AF.

Methods and Results: Isochronal activation mapping was performed during cardiac surgery on the right atria of patients in chronic AF (n = 13) using an epicardial electrode array. The atrial activation pattern was categorized using a complexity score based on the number of propagating wavefronts of activation and by grouping atria into those capable of uniform planar activation (simple) and those that were not (complex). The activation pattern was correlated with the levels of Cx43 and Cx40 signal measured by immunoconfocal quantification of biopsies from the mapped region. We studied the impact of electrical remodeling by comparing these findings with the unremodeled atria of patients in sinus rhythm during pacing‐induced sustained AF (n = 17). In chronic AF, atria with complex activation had lower Cx40 signal than atria showing simple activation (0.013 ± 0.006 μm2/μm2 vs 0.027 ± 0.009 μm2/μm2, P < 0.02), with the relative connexin signal (Cx40/Cx40+Cx43) correlating with complexity score (P = 0.01, r =−0.74). This relationship did not occur in the unremodeled atria, and increased heterogeneity of distribution of Cx40 labeling in chronic AF was the only evidence of connexin remodeling that we detected in the overall group.

Conclusion: The pattern of atrial activation is related to immunoconfocal connexin signal only in the fully remodeled atria of chronic AF. This suggests that intercellular coupling and pattern of atrial activation are interrelated, but only in conjunction with the remodeling of atrial electrophysiology that occurs in chronic AF. (J Cardiovasc Electrophysiol, Vol. 15, pp. 206‐213, February 2004)
Sinus Rhythm Electrogram Shape Measurements are Predictive of the Origins and Characteristics of Multiple Reentrant Ventricular Tachycardia Morphologies
Authors: CIACCIO EDWARD J. , COROMILAS JAMES , COSTEAS CONSTANTINOS A. , WIT ANDREW L.
Published: December 2004

Introduction: During clinical electrophysiologic study, multiple clinical tachycardia morphologies often can be induced in the infarct border zone, and all morphologies must be targeted for ablation therapy to be successful. Analysis of sinus rhythm electrogram shape for localizing figure‐of‐eight reentrant circuits in cases of multiple morphologies is proposed.

Methods and Results: Sinus rhythm activation maps were constructed from bipolar electrograms acquired at 196 to 312 sites in the epicardial border zone in 10 postinfarction canine hearts. In each heart, at least two distinct figure‐of‐eight reentrant ventricular tachycardia morphologies were inducible by premature electrical stimulation, as determined by activation maps of sustained tachycardias. Sinus rhythm maps were used to predict the location of the isthmus (central common pathway [CCP]), which is the protected region of the circuit bounded by arcs of block (mean accuracy 76.7 ± 4%). Although reentrant circuits differed, the positions of the entrance point of each CCP were common. The location of the line that would span the CCP at its narrowest width also was estimated (mean accuracy 91.3 ± 5%). Ablation at this line is expected to prevent reentry recurrence. In one test experiment, ablation prevented recurrence of both sustained reentrant tachycardia morphologies.

Conclusion: Sinus rhythm electrogram analyses are useful for (1) localizing multiple reentrant circuits with differences in morphology that are inducible by premature stimulation in the infarct border zone, and (2) locating and orienting the position of a linear lesion for preventing recurrence of all morphologies with minimal damage to the heart.
Atrial Ultrastructural Changes During Experimental Atrial Tachycardia Depend on High Ventricular Rate
Authors: SCHOONDERWOERD BAS A. , AUSMA JANNIE , CRIJNS HARRY J.G.M. , VAN VELDHUISEN DIRK J. , BLAAUW ENGBERT H. , VAN GELDER ISABELLE C.
Published: December 2004

Introduction: Atrial structural and electrophysiologic changes occur during atrial tachycardia. The role of high ventricular rate in these processes remains to be established.

Methods and Results: Six goats were subjected to 4 weeks of rapid atrioventricular (AV) pacing at an atrial and ventricular rate of 240 beats/min, resulting in development of congestive heart failure. In another five goats, AV block was created. These goats then were subjected to 4 weeks of atrial pacing, also at 240 beats/min while the ventricular rate was kept low and regular at 80 beats/min (A‐paced). Pacing was interrupted only for measurement of atrial effective refractory period and right atrial diameter. The ultrastructure of both atria was examined by light and electron microscopy, including quantification of the percentage of atrial extracellular matrix (%ECM). A group of six goats served as controls. In the AV‐paced group, severe structural remodeling occurred in the atria, including severe loss of sarcomeres, glycogen accumulation, disruption of sarcoplasmic reticulum, and appearance of numerous small mitochondria and nuclei with homogeneously distributed chromatin. In contrast, structural changes were virtually absent in the atria of A‐paced goats. Only a redistribution of nuclear chromatin and the appearance of numerous mitochondria were observed. The ultrastructure was normal in control animals. The%ECM was increased in AV‐paced goats (29%) compared to A‐paced animals (18%) and controls (17%) (P < 0.05). Finally, right atrial diameter increased by 51% in AV‐paced goats but was unchanged in A‐paced goats (P < 0.05). In both experimental groups, atrial effective refractory period shortened during pacing.

Conclusion: Structural remodeling during chronic atrial tachycardia is related to the concomitant presence of a high ventricular rate and hence the occurrence of congestive heart failure rather than a high atrial rate. Electrical remodeling can occur in the absence of significant structural changes.
Dual Conduction in a Mahaim Fiber
Authors: STERNICK EDUARDO BACK , SOSA EDUARDO A. , SCANAVACCA MAURÍCIO I. , WELLENS HEIN J.J.
Published: December 2004

The case of an 8‐year‐old girl with incessant nonsustained left bundle branch block‐like tachycardia refractory to antiarrhythmic drug therapy is reported. Electrophysiologic study revealed the presence of a right‐sided accessory atriofascicular pathway. Episodes of nonsustained tachycardia were found to be based upon a dual response in AV conduction over the Mahaim fiber to one P wave. No reentrant tachycardia could be induced. The arrhythmia was cured by catheter ablation targeting a Mahaim potential at the right lateral tricuspid annulus. The findings can be explained by longitudinal dissociation in a single Mahaim fiber, a fiber distally diverging into two fibers with different conduction times, or (less likely) two closely located Mahaim fibers with different conduction times.
Impact of Coronary Sinus Lead Position on Biventricular Pacing:
Authors: ROSSILLO ANTONIO , VERMA ATUL , SAAD EDUARDO B. , CORRADO ANDREA , GASPARINI GIANNI , MARROUCHE NASSIR F. , GOLSHAYAN ALI REZA , McCURDY RICHARD , BHARGAVA MANDEEP , KHAYKIN YAARIV , BURKHARDT J. DAVID , MARTIN DAVID O. , WILKOFF BRUCE L. , SALIBA WALID I. , SCHWEIKERT ROBERT A. , RAVIELE ANTONIO , NATALE ANDREA
Published: December 2004

Introduction: Biventricular pacing is an established treatment for congestive heart failure. Whether the anatomic location of the coronary sinus (CS) lead affects outcomes is unknown. The aim of this study was to evaluate the clinical response and mortality in patients who had transvenous CS leads placed in different anatomic branches for biventricular pacing.

Methods and Results: We evaluated 233 consecutive patients with New York Heart Association (NYHA) class III–IV heart failure and ejection fraction <35% who had successful placement of a transvenous left ventricular lead through a CS venous branch. Patients were divided into two groups based on anatomic lead position. Group 1 (n = 66) included leads in the anterior and anterolateral branches. Group 2 (n = 167) included leads in the lateral and posterolateral branches. Postimplant, functional capacity improved from an average 3.1 to 2.7 in group 1 (P = 0.001) and from 3.1 to 2.3 in group 2 (P = 0.001). Left ventricular ejection fraction (LVEF) measured by transthoracic echocardiography did not improve significantly in group 1 (pre‐LVEF 18%, post‐LVEF 20%; P = NS) but increased significantly from 19% to 27% in group 2 (P = 0.008). Despite the difference in ejection fraction response, the mortality in the two groups after a mean follow‐up of 546 days was similar (13.6% group 1 vs 17.9% group 2).

Conclusion: Placement of the CS lead in the lateral and posterolateral branches is associated with significant improvement in functional capacity and greater improvement in left ventricular function compared with the anterior CS location. This improvement does not appear to influence mortality.
Adaptive Diastolic Interval Control of Cardiac Action Potential Duration Alternans
Authors: JORDAN PETER N. , CHRISTINI DAVID J.
Published: December 2004

Introduction: Recent experimental and computational studies have shown that beat‐to‐beat alternation in action potential duration can trigger cardiac reentry, suggesting that such “alternans” is a mechanistic precursor to arrhythmias. Given such a link, termination of alternans may help prevent the onset of arrhythmias. To this end, recent efforts have shown that chaos control methods can modulate the timing of electrical stimulation to eliminate alternans.

Methods and Results: We have developed an alternative control method founded entirely in cardiac electrophysiology (rather than borrowing techniques from the control of physical systems as with existing control techniques). Using computer simulations, we show that this method, which exploits the rate‐dependent behavior of cardiac tissue, can be used to control alternans (and higher‐order) rhythms, and is robust to drift and noise. When applied to individual model cells exhibiting alternans, the algorithm converges to the period‐1 rhythm over as wide, and in some cases a wider, range of feedback proportionality constant values relative to existing methods. Control success comparable to existing methods is achieved when the algorithm is applied to a simulated one‐dimensional Purkinje fiber exhibiting alternans.

Conclusion: We have developed a method that adaptively controls the timing of electrical stimulation to rapidly eliminate action potential duration alternans in cardiac tissue. This control method may prove valuable in future arrhythmia prevention therapies.
Improved Localization of Right‐Sided Accessory Pathways with Microcatheter‐Assisted Right Coronary Artery Mapping in Children
Authors: SHAH MAULLY J. , JONES THOMAS K. , CECCHIN FRANK
Published: December 2004

Introduction: Radiofrequency ablation of some right‐sided accessory pathways continues to be challenging. The purpose of this study was to evaluate the efficacy of introducing a multielectrode microcatheter in the right coronary artery to localize accessory pathways when conventional mapping was unsuccessful.

Methods and Results: A retrospective study was conducted of all right‐sided accessory pathway radiofrequency ablation procedures in which a multielectrode microcatheter as a reference in the right coronary artery was used to assist mapping. Between January 1998 and January 2002, 10 patients (5 males) underwent mapping of 11 accessory pathways with this technique at mean age of 12.3 ± 3.8 years. Five patients had Ebstein's anomaly of the tricuspid valve. Accessory pathways were identified in the following locations: right anterior 3, right anterolateral 2, right lateral 1, right posterolateral 2, and right posterior 3. Mean procedure time was 285 ± 70.3 minutes, and fluoroscopy time was 68.7 ± 21 minutes. Average mapping duration prior to microcatheter insertion in the right coronary artery was 136 ± 40 minutes. After microcatheter placement in the right coronary artery, the time to successful ablation of accessory pathways was 38 ± 11 minutes. All 11 (100%) accessory pathways were successfully ablated.

Conclusion: Mapping in the right coronary artery with a microcatheter is an effective method to improve localization and successful ablation of difficult right‐sided accessory pathways.
Contagion Phenomena in Financial Crises: Evidence from the Portuguese and Spanish Exchange Rate Crises in the Early 1990s
Authors: Abreu Margarida
Published: December 2004

Based on the experience of the Portuguese and Spanish financial crises in the early 1990s, this paper suggests that the spillover of exchange rate crises may reveal a particular dimension of the financial contagion effect: the presumption of mimetic behaviour by monetary authorities.

This paper analyses the evolution of the credibility of the Escudo and the Peseta. We set out to test the existence of a contagion effect: that is, in what way does the polarization of exchange rate expectations in a scenario of devaluation of one currency explain the building up of a similar scenario for the other currency? We also examine the transmission mechanisms of such a scenario.

Our results suggest the existence of a one‐way contagion effect, of the Escudo by the Peseta. Speculative attacks against the Peseta necessarily give rise to speculative attacks against the Escudo, regardless of the evolution of the ‘fundamentals’ of the Escudo. In this case, the spillover of financial crises could be better understood by the anticipated mimetic behaviour of monetary authorities, rather than by the geographical proximity of the countries in question or by the identical performance of the economies of both.
Protecting the ageing poor or strengthening the market economy: the case of the Hong Kong Mandatory Provident Fund
Authors: Chan Chak Kwan
Published: December 2004

The Mandatory Provident Fund (MPF) launched by the Hong Kong government seems to be a residual welfare state's strategy to cope with an ageing population and, at the same time, preserve a minimal welfare state and further enhance economic development. The MPF can only provide limited protection for a limited number of employees; many older people still have to depend on financial support from their families or have to work. On the other hand, the MPF immediately boosts the economy by creating more jobs for the financial services sector and by providing more business opportunities for banks and insurance companies. Thus, the MPF has consolidated the foundation of Hong Kong's capitalism by socialising and incorporating the whole working population in the market economy but has provided little protection for their old age.