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Initial Success (initial + success)
Selected AbstractsCryoablation for Atrioventricular Nodal Reentrant Tachycardia in Young Patients: Predictors of RecurrencePACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 9 2008NIKHIL K. CHANANI M.D. Background: Recurrence rates of atrioventricular nodal reentry tachycardia (AVNRT) after cryoablation continue to remain high despite excellent initial success rates. Our objective was to evaluate the clinical outcomes of cryoablation for AVNRT with the 4-mm and 6-mm tip cryoablation catheters in a young population and to elicit predictors of arrhythmia recurrence. Methods: We retrospectively reviewed all patients who underwent cryoablation for AVNRT at the UCSF/Stanford Pediatric Arrhythmia Center from January 2004 to February 2007. Results: One hundred fifty-four patients (age 13.7 years (3.2,24.4)) underwent cryoablation for AVNRT of which 144 patients had inducible AVNRT (123 sustained and 21 nonsustained) and 10 had presumed AVNRT. Initial success was achieved in 95% (146/154), with no difference between the 4-mm (93%) and 6-mm (98%) cryoablation catheter tips (P = 0.15). There was no permanent atrioventricular (AV) block. Transient third-degree AV block occurred in nine patients (6%), with no difference between the 4-mm (4%) and 6-mm (9%) tip (P = 0.13). AVNRT recurrence was documented in 14% in a median time of 2.5 months (0.25,20). Recurrences were lower with the 6-mm (9%) versus the 4-mm (18%) tip, but this did not reach statistical significance (P = 0.16). With univariate analysis, a longer fluoroscopy time was the only significant factor associated with recurrence. Multivariate analysis failed to identify any significant predictor of AVNRT recurrence. Conclusion: Outcomes of cryoablation for AVNRT continue to be good without the complication of AV block. We could not identify any specific parameter associated with AVNRT recurrence. Further improvements in cryoablation technique will be necessary to reduce recurrences. [source] Prospective assessment of hemodialysis access patency after percutaneous intervention: Cox proportional hazards analysisCATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 3 2005John A. Bittl MD Abstract Vascular access failure is the greatest limitation of successful hemodialysis, but the factors associated with long-term patency have not been fully elucidated. Outcomes in a consecutive series of 294 thrombosed or failing accesses [128 fistulas (43.5%) and 166 grafts (56.5%) in 179 patients] were analyzed with life table and multivariable Cox proportional hazards analysis. Initial success was achieved in 275 of 294 accesses (95.6%). The median patency after intervention was 206 days (interquartile range, 79,457 days). Fistulas had longer median patency after intervention than grafts (286 vs. 170 days). Nonthrombosed accesses had longer median patency than thrombosed accesses (238 vs. 136 days), but thrombosed fistulas had similar median patency as thrombosed grafts (140 vs. 136 days). The selective use of stents as a bailout for failed balloon dilatation did not significantly reduce long-term patency (196 days for stented accesses vs. 210 days for unstented accesses). Long-term patency was inversely related to final access pressure, but access patency was not related to the presence of central venous occlusions, graft age, patient age, sex, or diabetes. Catheter-based intervention of thrombosed and failing dialysis accesses significantly prolongs patency and usefulness of dialysis accesses. The expanding use of fistulas, improved detection of early access failure, and selective use of bailout stents should enhance long-term access patency. © 2005 Wiley-Liss, Inc. [source] Introduction Strategies Put to the Test: Local Adaptation versus HeterosisCONSERVATION BIOLOGY, Issue 3 2004PHILIPPINE VERGEER exogamia; introducciones multi-fuente; introducciones uni-fuente; Succisa pratensis Abstract:,Plant biodiversity has declined seriously because of both habitat deterioration and habitat fragmentation. As a result, many species have been forced into small, fragmented, and isolated populations and are believed to suffer from higher extinction risks. Genetic reinforcement and the establishment of new populations are now widely used to prevent extinction. However, the genetic background of transplants may seriously affect the long-term success of these populations because increased genetic variation may reduce the risk of inbreeding or lead to better performance by restored heterozygosity levels (heterosis). Introduced transplants, however, may be poorly adapted to the new local conditions. We tested the initial success of alternative introduction strategies. We evaluated the potential for inbreeding, heterosis, and/or local adaptation after introduction of artificial populations of Succisa pratensis. We introduced individuals from local and distant artificial populations that were created from either small or large populations. We created the artificial populations with the same census population size but varying effective population sizes by adjusting the relatedness of individuals. We analyzed the demographic consequences of inbreeding, heterosis, and/or local adaptation of these artificial populations. Reduced performance after selfing was manifested by a reduction in seed production, seed weight, germination, and flowering percentage. Seed production, seed weight, flowering percentage, and number of flowerheads were negatively affected by small population size. Local adaptation increased biomass and flowering percentage for local individuals. Seed weight and seed production exhibited significant heterosis. Our results demonstrate that threatened populations can benefit from introduction and genetic reinforcement of individuals from related populations. Significant differences among the artificial populations for several measured performance components suggest that introduction or reinforcement is best achieved through material from a local population or, when unavailable, from several large populations. Resumen:,La biodiversidad de plantas ha declinado seriamente tanto por el deterioro como la fragmentación de hábitats. Como resultado, muchas especies han sido relegadas a poblaciones pequeñas, fragmentadas y aisladas cuyos riesgos de extinción se piensa que son mayores. El reforzamiento genético y el establecimiento de poblaciones nuevas se utilizan ampliamente en la actualidad para prevenir la extinción. Sin embargo, los antecedentes genéticos de transplantes pueden afectar seriamente el éxito de estas poblaciones a largo plazo debido a que el incremento en la variación genética puede reducir el riesgo de endogamia o puede conducir a un mejor rendimiento por lograr niveles de heterocigosidad restaurados (heterosis). No obstante, los trasplantes introducidos pueden adaptarse deficientemente a las nuevas condiciones locales. Probamos el éxito inicial de estrategias de introducción alternativas. Evaluamos el potencial de endogamia, heterosis y/o adaptación local después de la introducción de poblaciones artificiales de Succisa pratensis. Introdujimos individuos de poblaciones locales y de poblaciones artificiales distantes que fueron creadas a partir de poblaciones tanto pequeñas como grandes. Las poblaciones artificiales fueron creadas con el mismo tamaño poblacional censal pero variaron en tamaños poblacionales efectivos al ajustar la parentela de los individuos. Analizamos las consecuencias demográficas de la endogamia, heterosis y/o adaptación local de estas poblaciones artificiales. Después de la autofecundación se manifestó una reducción en el rendimiento por reducción en la producción y peso de semillas y en el porcentaje de germinación y floración. La producción y peso de semillas, el porcentaje de floración y el número de botones florales fueron afectados negativamente por el tamaño poblacional pequeño. La adaptación local incrementó la biomasa y el porcentaje de floración en individuos locales. El peso y producción de semillas mostró heterosis significativa. Nuestros resultados demuestran que las poblaciones amenazadas pueden beneficiarse de la introducción y del reforzamiento genético de individuos de poblaciones emparentadas. Las diferencias significativas entre las poblaciones artificiales en varios de los componentes de rendimiento medidos sugiere que la introducción o reforzamiento se logra mejor con material de una población local o, cuando no disponible, con material de varias poblaciones grandes. [source] New developments in small molecules targeting p53 pathways in anticancer therapyDRUG DEVELOPMENT RESEARCH, Issue 6 2008Chit Fang Cheok Abstract The tumor suppressor p53 is frequently inactivated in a wide variety of cancers and point mutations or deletions of the p53 gene are associated with poor prognosis in cancer. About half of all human tumors carry wildtype p53 but p53 wildtype functions are often suppressed by the overexpression of murine double minute 2 (MDM2), a negative regulator of p53. Restoration of p53 functions in tumor cells, therefore, represents an attractive strategy in combating cancer and has been the focus of intensive anticancer drug discovery. One strategy is to antagonize MDM2 functions and initial success was demonstrated in vitro and in xenograft tumor models using newly discovered small molecule inhibitors and antisense oligonucleotides. The new discovery of a compound targeting SirT1 (a member of the sirtuin family) in a p53-dependent reporter screen highlighted the importance of another negative regulator of p53 and offers an additional avenue for drug discovery and research on p53-activating therapeutics. Here, we discuss the developments of p53-activating small molecules and their potential use in combination therapy with established chemotherapeutics. These small molecules were discovered from chemical library screening using biochemical assays or cellular-based assays, and/or structure-based rational drug design strategies. Drug Dev Res 69:289,296, 2008. © 2008 Wiley-Liss, Inc. [source] Pharmacological interventions in aging and age-associated disordersGERIATRICS & GERONTOLOGY INTERNATIONAL, Issue 2 2007Kenichi Kitani In the present study, past attempts using different pharmaceuticals and chemicals which were reported to prolong lifespans of animals are critically reviewed. Despite a large number of trials in animals and humans, the validity of supplementation of antioxidant vitamins such as vitamins A, E and C for improving human health remains unresolved at present. A recent approach using antioxidant mimetics called the EUK series which, despite an initial enthusiastically reported success in prolonging the lifespan of nematodes, remains again unsettled because of the failure in reproducing the initial success by follow-up studies. ,-Phenyl- tert -butylnitrone and related nitrones were initially introduced as radical scavengers. Some of these (e.g. disodium 2,4-disulfophenyl-N- tert -butylnitrone) are at phase 3 clinical trials as an agent to treat cerebral stroke. This effect, however, appears at least in part to be related to signal transduction which makes these agents effective against cerebral stroke even when they are administered later than its onset. (,)Deprenyl is a monoamine oxidase-B inhibitor and has some neuroprotective and anti-apoptotic effects. The drug has also been shown to prolong the lifespans of at least four different animal species. The drug upregulates superoxide dismutase and catalase activities in selective brain regions of dopaminergic nature. These effects on antioxidant enzyme activities are suspected to be causally related to its effect on lifespans of animals. Future trials using these and other drugs are expected to open new doors for interventions in aging and age-associated disorders in humans. [source] Adult-to-adult right hepatic lobe living donor liver transplantationALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 11 2002P. H. Hayashi Summary Spurred on by the critical shortage of cadaveric livers, adult-to-adult right hepatic lobe living donor liver transplantation has grown rapidly as a therapeutic option for selected patients. In the USA alone, the number of living donor liver transplantations has increased six-fold in the last 4 years. The therapy can be complex, bringing together a variety of disciplines, including transplantation medicine and surgery, hepatology, psychiatry and medical ethics. Moreover, living donor liver transplantation is still defining itself in the adult-to-adult application. Uniform standards, guidelines and long-term outcomes are yet to be determined. Nevertheless, initial success has been remarkable, and a basic understanding of this field is essential to any physician contemplating options for their liver failure patients. This review covers a range of topics, including recipient and donor selection and outcomes, donor risk, controversies and future issues. [source] Parent-administered modified dry-bed training for childhood nocturnal enuresis: evidence for superiority over urine-alarm conditioning when delivery factors are controlledBEHAVIORAL INTERVENTIONS, Issue 4 2002Shazia Nawaz We compared the relative efficacy of modified dry-bed training and standard urine-alarm conditioning for treating functional nocturnal enuresis in 36 children aged 7,12 years attending health centres in Glasgow, Scotland. A minimal intervention, self-help approach was adopted. Parents and children received standardized instruction, which, for each method, consisted of one clinic interview and a manual and videotape for home viewing. Outcomes were contrasted with those from untreated controls. Twelve children were randomly assigned to each condition. All groups were matched for age, gender, social class (deprivation category), and baseline wetting frequency. In the two treated groups, an intake interview was followed by two review appointments, otherwise families carried out the programmes independently at home with fortnightly telephone support either until the success criterion of 14 consecutive dry nights was met or the 16 week maximum treatment period expired. Of the 12 children treated by dry-bed training, eight achieved initial success compared with only three of the 12 treated by the conventional urine-alarm method. One waiting-list control child remitted spontaneously. ANOVA showed highly significant differences in wet nights per week immediately after intervention for both treatment and time factors (p,<,0.001) and their interaction (p,<,0.01). The dry-bed group averaged 0.8 nights per week wet on treatment cessation, a frequency which was significantly superior to the average of 3.25 for the urine-alarm group and 5.00 for the controls. Six months after attaining initial success, one child in each treated group had relapsed. Our results show an outcome of 58% long-term remission (67% initial arrest, 13% relapse) for dry-bed training when delivered by minimal intervention methods and indicate dry-bed training as being more effective than orthodox urine-alarm conditioning for the same input of clinic time and instruction. Copyright © 2002 John Wiley & Sons, Ltd. [source] Home-dilatation of the urethral meatus in boysBJU INTERNATIONAL, Issue 4 2004J.M. Searles OBJECTIVES To evaluate the efficacy of dilatation of the stenotic urethral meatus in boys at home. PATIENTS AND METHODS Eighteen boys aged 3,15 years, or their parents, were taught to dilate the urethral meatus at home. The cause of the stricture was balanitis xerotica obliterans (BXO) in five and consequent upon hypospadias surgery in 12, of whom two were complicated by BXO, and one after circumcision for cultural reasons. One boy was re-referred after an interval of 3 years because of apparent deterioration of the stream of urine. Meatal dilatation was taught in the home by one of the authors (J.M.S.) RESULTS Nine patients were cured by the first course of dilatation, four relapsed early after initial success but responded to further treatment, and three proceeded to meatoplasty because they had no response. Two relapsed late and one responded to further dilatation but the other required surgery. CONCLUSION Dilatation of the urethral meatus can be taught successfully to boys or their families at home, thus avoiding repeated hospital attendance and often general anaesthesia. [source] Comparison of extra-anatomic bypass grafting with angioplasty for atherosclerotic disease of the supra-aortic trunksBRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 11 2004B. Modarai Background: Symptomatic stenosis of the supra-aortic trunks (subclavian, innominate and common carotid arteries) can be treated by angioplasty/stenting or surgical bypass. The aim of this study was to compare the initial success and outcome of these two types of treatment. Methods: A prospective database was used to collect information on the presentation, initial success, complications and outcome in 76 patients treated in a single centre between 1983 and 2003. Results: Thirty-five surgical extra-anatomic bypasses were performed, 13 carotid to carotid, 14 carotid to subclavian, two carotid to axillary, three axillary to axillary, one subclavian to axillary and two subclavian to subclavian. One graft occluded after 19 years. No limbs were amputated and no patient had a stroke. The secondary patency rate was 97 per cent at a mean follow-up of 5 years. Forty-one angioplasties were attempted, 34 of the left subclavian, six of the right subclavian and one of the innominate artery. Angioplasty for six subclavian occlusions was unsuccessful. Twenty-seven of 33 arteries remained patent at a mean follow-up of 4 years after a successful endovascular procedure. Conclusion: Extra-anatomic bypass for supra-aortic trunk disease has a better patency than angioplasty, with a comparable complication rate. Copyright © 2004 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd. [source] Enthalpy/Entropy Compensation in the Melting of Thermotropic Nitrogen-Containing Chelating Ligands and Their Lanthanide Complexes: Successes and Failures,,EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 18 2010Aude Escande Abstract In this short overview dedicated to the thermodynamics of liquid crystalline chelating nitrogen-containing ligands and their lanthanide complexes (i.e., lanthanidomesogens), we first go through the initial successes obtained with the introduction of the concept of enthalpy/entropy compensation for rationalizing and programming melting and clearing temperatures in thermotropic mesophases. In the second part, the failures encountered during our attempts for switching from a qualitative toward a quantitative interpretation of the melting processes in polycatenar lanthanidomesogens are discussed, together with the delicate correlations established between the thermodynamic parameters of intermolecular cohesion measured in noncoordinating solvents and those operating in pure mesophases. [source] Accomplishments in genome-scale in silico modeling for industrial and medical biotechnologyBIOTECHNOLOGY JOURNAL, Issue 12 2009Caroline B. Milne Abstract Driven by advancements in high-throughput biological technologies and the growing number of sequenced genomes, the construction of in silico models at the genome scale has provided powerful tools to investigate a vast array of biological systems and applications. Here, we review comprehensively the uses of such models in industrial and medical biotechnology, including biofuel generation, food production, and drug development. While the use of in silico models is still in its early stages for delivering to industry, significant initial successes have been achieved. For the cases presented here, genome-scale models predict engineering strategies to enhance properties of interest in an organism or to inhibit harmful mechanisms of pathogens. Going forward, genome-scale in silico models promise to extend their application and analysis scope to become a transformative tool in biotechnology. [source] | |||||||||||||