Radiofrequency catheter ablation of persistent atrial fibrillation by pulmonary vein isolation with or without left atrial posterior wall isolation: long-term outcomes of the CAPLA trial.

BACKGROUND AND AIMS: Posterior wall isolation (PWI) is commonly incorporated into catheter ablation (CA) strategies for persistent atrial fibrillation (AF) in an attempt to improve outcomes. In the CAPLA randomized study, adjunctive PWI did not improve freedom from atrial arrhythmia at 12 months compared with pulmonary vein isolation (PVI) alone. Whether additional PWI reduces arrhythmia recurrence over the longer term remains unknown. METHODS: In this multicenter, international, randomized study patients with persistent AF undergoing index CA using radiofrequency (RF) were randomized to PVI+PWI versus PVI alone. Patients underwent regular follow-up including rhythm monitoring for a minimum of 3 years post CA. AF burden at 3 years post-ablation was evaluated with either 28-day continuous ambulatory ECG monitoring, twice daily single-lead ECG or from cardiac implanted device. Evaluated endpoints included freedom from any documented atrial arrhythmia recurrence after a single procedure, AF burden, need for redo catheter ablation, rhythm at last clinical follow-up, healthcare utilisation metrics and AF-related quality of life. RESULTS: 333 of 338 (98.5%) patients (mean age 64.3±9.4 years, 23% female) completed 3-year follow-up, with 169 patients randomized to PVI+PWI and 164 patients to PVI alone. At a median of 3.62 years post-index ablation, freedom from recurrent atrial arrhythmia occurred in 59 patients (35.5%) randomized to PVI+PWI vs 68 patients (42.1%) randomized to PVI alone (HR 1.15, 95% CI 0.88-1.51, p=0.55). Median time to recurrent atrial arrhythmia was 0.53 years (IQR 0.34-1.01 years). Redo ablation was performed in 54 patients (32.0%) in the PVI+PWI group vs 49 patients (29.9%, p=0.68) in the PVI alone group. Pulmonary vein reconnection was present in 54.5% (mean number of reconnected PVs 2.2±0.9) and posterior wall reconnection in 75%. Median AF burden at 3 years was 0% in both groups (IQR 0-0.85% PVI+PWI vs 0-1.43% PVI alone, p=0.49). Sinus rhythm at final clinical follow-up was present in 85.1% with PVI+PWI vs 87.1% with PVI alone (p=0.60). Mean AF Effect On Quality-Of-Life (AFEQT) score at 3 years post-ablation was 88.0±14.8 with PVI+PWI vs 88.9±15.4 with PVI alone (p=0.63). CONCLUSIONS: In patients with persistent AF, the addition of PWI to PVI alone at index RF catheter ablation did not significantly improve freedom from atrial arrhythmia recurrence at long-term follow-up. Median AF burden remains low and AF quality of life high at 3 years with either ablation strategy.

Pulmonary vein antral isolation for paroxysmal atrial fibrillation: results from long-term follow-up.

INTRODUCTION: Pulmonary veins play an important role in triggering atrial fibrillation (AF). Pulmonary vein isolation (PVI) is an effective treatment for patients with paroxysmal AF. However, the late AF recurrence rate in long-term follow-up of circumferential PV antral isolation (PVAI) is not well documented. We sought to determine the time to recurrence of arrhythmia after PVAI, and long-term rates of sinus rhythm after circumferential PVAI. METHODS: One hundred consecutive patients with a mean age of 54 ± 10 years, with paroxysmal AF who underwent PVAI procedure were analyzed. Isolation of pulmonary veins was based on an electrophysiological and anatomical approach, with a nonfluoroscopic navigation mapping system to guide antral PVI. Ablation endpoint was vein isolation confirmed with a circular mapping catheter at first and subsequent procedures. Clinical, ECG, and Holter follow-up was undertaken every 3 months in the first year postablation, every 6 months thereafter, with additional prolonged monitoring if symptoms were reported. Time to arrhythmia recurrence, and representing arrhythmias, were documented. RESULTS: Isolation of all 4 veins was successful in 97% patients with 3.9 ± 0.3 veins isolated/patient. Follow-up after the last RF procedure was at a mean of 39 ± 10 months (range 21-66 months). After a single procedure, sinus rhythm was maintained at long-term follow-up in 49% patients without use of antiarrhythmic drugs (AADs). After repeat procedure, sinus rhythm was maintained in 57% patients without the use of AADs, and in 82% patients including patients with AADs. A total of 18 of 100 patients had 2 procedures and 4 of 100 patients had 3 procedures for recurrent AF/AT. Most (86%) AF/AT recurrences occurred ≤ 1 year after the first procedure. Mean time to recurrence was 6 ± 10 months. Kaplan-Meier analysis on antiarrhythmics showed AF free rate of 87% at 1 year and 80% at 4 years. There were no major complications. CONCLUSION: PVAI is an effective strategy for the prevention of AF in the majority of patients with PAF. Maintenance of SR requires repeat procedure or continuation of AADs in a significant proportion of patients. After maintenance of sinus rhythm 1-year post-PVAI, a minority of patients will subsequently develop late recurrence of AF.

Taxonomic revision transferring species in Kuklospora to Acaulospora (Glomeromycota) and a description of Acaulospora colliculosa sp. nov. from field collected spores.

In a phylogenetic study of arbuscular mycorrhizal fungal species in Acaulospora (Acaulosporaceae, Glomeromycota) we discovered that species classified in genus Kuklospora, a supposed sister clade of Acaulospora, did not partition as a monophyletic clade. Species in these two genera can be distinguished only by the position of the spore relative to a precursor structure, the sporiferous saccule, as either within (entrophosporoid) or laterally (acaulosporoid) on the saccule subtending hypha. Subsequent spore differentiation follows identical patterns and organization. Molecular phylogeny reconstructed from nrLSU gene sequences, together with developmental data, support the hypothesis that the entrophosporoid mode of spore formation evolved many times and thus represents a convergent trait of little phylogenetic significance. Therefore genus Kuklospora is rejected as a valid monophyletic group and it is integrated taxonomically into genus Acaulospora. Thus Acaulospora colombiana and Acaulospora kentinensis are erected as new combinations (formerly Kuklospora colombiana and Kuklospora kentinensis). Mode of spore formation is demoted from a genus-specific character to one that is included with other traits to define Acaulospora species. In addition we describe a new AM fungal species, Acaulospora colliculosa (Acaulosporaceae), that originated from a tallgrass prairie in North America. Field-collected spores of A. colliculosa are small (<100 µm diam), hyaline or subhyaline to pale yellow and form via entrophosporoid development based on structure and organization of cicatrices and attached hyphae. Each spore consists of a bilayered spore wall and two bilayered inner walls. A germination orb likely forms after the completion of spore development to initiate germination, but this structure was not observed. A character distinguishing A. colliculosa from other Acaulospora species is hyaline to subhyaline hemispherical protuberances on the surface of the outer spore wall layer. A phylogeny reconstructed from partial nrLSU gene sequences unambiguously placed A. colliculosa in the Acaulospora clade.

CanDiD: A Framework for Linking Executive Function and Education.

The close association between executive functions (EFs) and educational achievement has led to the idea that targeted EF training might facilitate learning and goal-directed behavior in the classroom. The evidence that training interventions have long-lasting and transferable effects is however decidedly mixed (Melby-Lervåg and Hulme, 2013; Simons et al., 2016). The goal of the current paper is to propose a new CanDiD framework for re-thinking EF and its links to education. Based on findings from basic EF research, the proposed CanDiD framework highlights dynamic and contextual influences on EF and emphasizes the importance of development and individual differences for understanding these effects. Implications for remedial interventions and curriculum design are discussed.

Diazepam and haloperidol. Effect on regional brain homovanillic acid levels.

Diazepam lowered homovanillic acid levels in brain regions from untreated and haloperidol-treated rats. However, there was evidence of a biphasic effect in that 2 mg/kg was more effective than 10 mg/kg under several conditions. Diazepam was more effective in restoring regional HVA toward control levels following doses of haloperidol in the low clinical range (0.1 to 0.2 mg/kg) than following higher doses. With respect to maximizing dopamine receptor blockade and minimizing compensatory presynaptic activity in the acute treatment of psychotic conditions, our data provide some support for the use of modest doses of neuroleptics and benzodiazepines.

A combined morphological and molecular approach to characterize isolates of arbuscular mycorrhizal fungi in Gigaspora (Glomales).

• Morphological features of resting spores and information from nucleotide sequences of ribosomal RNA were used to characterize seven mycorrhizal fungal isolates in Gigaspora from different geographical areas. • Detailed observations were made under the light microscope on single spores mounted in Melzer's reagent and polyvinyl alcohol-lactic acid-glycerol medium to resolve size, colour and cell wall structures. Neighbour-joining analyses were carried out on a portion of the 18S gene and on the internal transcribed spacer (ITS) region amplified by PCR from multisporal DNA preparations. • Combined data allowed us to design oligonucleotides that unambiguously distinguished Gi. rosea from Gi. margarita and Gi. gigantea and also identified two isolates as Gi. rosea that had been previously diagnosed as Gi. margarita. ITS sequences revealed substantial genetic variability within clones of a single isolate of Gi. rosea as well as among geographically disjunct Gi. rosea isolates. • The results show how complementary morphological and molecular data can clarify relationships among species of low morphological divergence. Sequence information allowed the extent of genetic divergence within these species to be investigated and provided useful PCR primers for detection and identification.

Diazepam antagonizes effects on dopamine metabolism produced by PCP receptor agonists.

1. Male rats were injected with either saline, diazepam, MK-801, or diazepam plus MK-801. 2. In previous work with phencyclidine (PCP), diazepam significantly reduced the increase in homovanillic acid (HVA) in olfactory tubercle and prefrontal cortex. 3. Diazepam also lowered the HVA increase following MK-801 in caudate, olfactory tubercle, and prefrontal cortex. 4. Benzodiazepine receptors may modify dopaminergic function at PCP receptors that affect dopamine neurotransmission.

Regional brain catecholamines and metabolites following THC, PCP and MK-801.

1. THC, PCP, and MK-801 increased DOPAC in rat olfactory tubercle and prefrontal cortex without affecting DA levels, suggesting increased DA release. 2. Effects on NE and MHPG were not evident. 3. These two classes of drugs can effect dopaminergic systems independently of noradrenergic systems.

A team process for the introduction of the laparoscopic cholecystectomy technique to a public hospital service.

AIMS: To introduce the technique of laparoscopic cholecystectomy to Christchurch hospitals by a process involving all surgeons in the general surgical team. To assess prospectively the potential for cost-saving. METHOD: A visiting surgeon with experience of the procedure, demonstrated the technique and supervised operations by members of the team on twenty six informed consenting patients. RESULTS: The process has enabled all general surgeons to gain competence in the technique, with low complication rates. CONCLUSIONS: The process adopted in Christchurch quickly familiarised all general surgeons with the technique of laparoscopic cholecystectomy, so that it was safely and efficiently made available to all patients who could benefit. The capacity of the procedure to reduce the cost per case treated was assessed, and reduced social cost to patients demonstrated.

Cadaver kidney retrieval for transplantation in Canterbury and Westland: 1972-1987.

In Canterbury and Westland, 106 cadaver kidney donors have provided 186 kidneys, which have been transplanted or submitted for transplantation. The overall rate of 16 donor/million population/year, since 1973, is high by international standards [1,2]. Male donors (68%) had a median age of 20 years, and females a median age of 24 years. Motor vehicle accidents were responsible for 58% of deaths, followed by subarachnoid haemorrhage (15%). Cadaver nephrectomy was performed outside normal working hours in 58% of cases. Overall, 10% of kidneys removed were discarded, but none have been discarded since September 1980. Anatomical anomalies were common (42%).

Living related renal transplantation: the Christchurch experience.

AIM: To determine the outcome of renal transplants from living related donors. METHODS: Retrospective analysis of 33 living related donor renal transplants done between March 1976 and 31 December 1994 at Christchurch Hospital. RESULTS: One of the 33 renal transplants patients received an ABO incompatible kidney and was excluded from the statistical analysis. Twenty-one (66%) of 32 grafts continue to function. The 1, 5 and 10 year graft survival rates were 82%, 73% and 48%, respectively. The estimated 1 and 10 year patient survival rates were 96% and 94%, respectively. With the introduction of cyclosporin the 1 and 5 year graft survival rates increased to 90% and 80%, respectively. Three patients received donor specific transfusion preconditioning and one patient a skin graft from the prospective donor. Four patients (12.5%) had current and/or peak panel reactive antibody titres of more than 25%. Three of these grafts failed after 2, 95 and 463 days. Two grafts were lost due to catastrophic vascular complications. CONCLUSION: The overall outcome for patients who were not highly sensitised was excellent. The degree of sensitisation of the recipient, and the extent of atherosclerotic vascular disease in the recipient, were major predisposing factors for the graft loss due to rejection and vascular complications during the early post transplant period.

Variation in aluminum resistance among arbuscular mycorrhizal fungi.

Arbuscular mycorrhizal (AM) fungi mediate interactions between plants and soils, and are important where nutrient or metal concentrations limit plant growth. Variation in fungal response to edaphic conditions may influence the effectiveness of the plant-mycorrhizal association in some soil environments. Andropogon virginicus (broomsedge) colonizes disturbed sites in the eastern United States, including acidic mine soils where aluminum (Al) is phytotoxic, and Al resistance in broomsedge has been associated with colonization by the AM fungus Glomus clarum. In the present study, inter- and intra-specific variation to confer Al resistance to broomsedge was assessed among selected species of AM fungi. Broomsedge seeds were grown in sand culture inoculated with one of five isolates of three species of fungi (G. clarum, Acaulospora morrowiae, and Scutellospora heterogama). Plants were exposed to 0 or 400 microM Al in nutrient solution and harvested after 4 or 9 weeks of growth. Mean infection percentage, plant biomass, and plant tissue Al and phosphorus (P) concentrations were measured. G. clarum conferred the greatest Al resistance to broomsedge, with the lowest variability among isolates for colonization and growth inhibition by Al [tolerance indices (TI) between 22.4 and 92.7%]. Broomsedge plants colonized by A. morrowiae were consistently the most sensitive to Al, with little variation among isolates (TI between 1.6 and 12.1%). Al resistance by S. heterogama isolates was intermediate and wide-ranging (TI between 3.9 and 40.0%). Across all AM fungal isolates, resistance was associated with high rates of colonization and low tissue Al concentrations of broomsedge plants. The functional diversity in Al resistance displayed by these AM fungi reflect variation in acclimation mechanisms operating in the mycorrhizal symbiosis under environmental stress.

Congruence of fatty acid methyl ester profiles and morphological characters of arbuscular mycorrhizal fungi in Gigasporaceae.

Arbuscular mycorrhizal (AM) fungi (Order Glomales, Class Zygomycetes) are a diverse group of soil fungi that form mutualistic associations with the roots of most species of higher plants. Despite intensive study over the past 25 years, the phylogenetic relationships among AM fungi, and thus many details of evolution of the symbiosis, remain unclear. Cladistic analysis was performed on fatty acid methyl ester (FAME) profiles of 15 species in Gigaspora and Scutellospora (family Gigasporaceae) by using a restricted maximum likelihood approach of continuous character data. Results were compared to a parsimony analysis of spore morphological characters of the same species. Only one tree was generated from each character set. Morphological and developmental data suggest that species with the simplest spore types are ancestral whereas those with complicated inner wall structures are derived. Spores of those species having a complex wall structure pass through stages of development identical to the mature stages of simpler spores, suggesting a pattern of classical Haeckelian recapitulation in evolution of spore characters. Analysis of FAME profiles supported this hypothesis when Glomus leptotichum was used as the outgroup. However, when Glomus etunicatum was chosen as the outgroup, the polarity of the entire tree was reversed. Our results suggest that FAME profiles contain useful information and provide independent criteria for generating phylogenetic hypotheses in AM fungi. The maximum likelihood approach to analyzing FAME profiles also may prove useful for many other groups of organisms in which profiles are empirically shown to be stable and heritable.

Cadaver nephrectomy: an operation on the donor's family.

Thirty-two relatives of cadaver kidney donors were interviewed six months or longer after the donor's death. Most had positive attitudes to kidney transplantation that had been strengthened by experience, especially when they knew that they were fulfilling the donor's wishes. Twenty-three of the relatives had gained some solace from knowing that others might benefit from their misfortune, but three claimed adverse effects. In identifying the factors that influenced them to grant permission or hesitate, relatives revealed defects in the way their permission had been sought. Twelve did not clearly understand the donor's hopeless prognosis until then, and seven reacted adversely to the interviewers, finding them blunt and callous. Nevertheless, most were pleased that they had been asked. Doctors who care for unconscious, dying patients should try to give relatives explicit information on the patient's condition, whether or not the patient is a potential kidney donor, and permission for organ recovery should not be sought until they understand that death is inevitable.

Correlations between staff, peer and self assessments of fourth-year students in surgery.

Self, peer and staff assessments were made for 138 of 141 students, in two fourth-year surgery classes. Self assessments were significantly lower than peer assessments, which in turn were significantly lower than staff assessments. The highest correlation was between peer and staff assessments. Students with serious psychological problems identified themselves with failing self assessments. The study stimulated interest in assessment procedures amongst staff and students and the latter responded with an assessment of teachers and courses throughout the faculty.

Children's understanding of emotion in speech.

Children's understanding of emotion in speech was explored in three experiments. In Experiment 1, 4- to 10-year-old children and adults (N = 165) judged the happiness or sadness of the speaker from cues conveyed by propositional content and affective paralanguage. When the cues conflicted (i.e., a happy situation was described with sad paralanguage), children relied primarily on content, in contrast to adults, who relied on paralanguage. There were gradual developmental changes from 4-year-olds' almost exclusive focus on content to adults' exclusive focus on paralanguage. Children of all ages exhibited greater response latencies to utterances with conflicting cues than to those with nonconflicting cues, indicating that they processed both sources of emotional information. Children accurately labeled the affective paralanguage when the propositional cues to emotion were obscured by a foreign language (Experiment 2, N = 20) or by low-pass filtering (Experiment 3, N = 60). The findings are consistent with children's limited understanding of the communicative functions of affective paralanguage.

Detection of vesicular-arbuscular mycorrhizal fungus colonization of roots by using a dot-immunoblot assay.

An immunoblotting procedure was developed to overcome the difficulty in identifying root colonization by a vesicular-arbuscular mycorrhizal fungus. The procedure utilized a murine monoclonal antibody that reacts with a protein in spores and hyphae of Glomus occultum, a fungus characterized by abundant production of hyaline spores and nonstaining intraradical infection. Minimally disturbed whole roots were squashed on nitrocellulose membranes. After inactivation of endogenous peroxidase, an indirect enzyme-linked immunosorbent assay was performed on the nitrocellulose with peroxidase-conjugated anti-mouse antibody as the second antibody. Antigen from G. occultum, revealed by a precipitating stain, was seen as purple dots on the nitrocellulose, which also retained the impression of the root.

Traumatic transection of the pancreas: a report of four cases.

Four patients with transection of the pancreas by blunt trauma are reported. All were treated by distal pancreatectomy and splenectomy. The three patients who survived were free from exocrine or endocrine deficiency at the time of discharge from hospital. One patient, whose transection was missed at the initial laparotomy, was operated upon later when in renal failure, and died from sepsis. Distal pancreatectomy with splenectomy seems the appropriate because other operations have high complication rates, and extirpation of the distal pancreas is not debilitating.