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1.
Proc Natl Acad Sci U S A ; 121(12): e2318716121, 2024 Mar 19.
Article in English | MEDLINE | ID: mdl-38483991

ABSTRACT

Deep convection in the Asian summer monsoon is a significant transport process for lifting pollutants from the planetary boundary layer to the tropopause level. This process enables efficient injection into the stratosphere of reactive species such as chlorinated very-short-lived substances (Cl-VSLSs) that deplete ozone. Past studies of convective transport associated with the Asian summer monsoon have focused mostly on the south Asian summer monsoon. Airborne observations reported in this work identify the East Asian summer monsoon convection as an effective transport pathway that carried record-breaking levels of ozone-depleting Cl-VSLSs (mean organic chlorine from these VSLSs ~500 ppt) to the base of the stratosphere. These unique observations show total organic chlorine from VSLSs in the lower stratosphere over the Asian monsoon tropopause to be more than twice that previously reported over the tropical tropopause. Considering the recently observed increase in Cl-VSLS emissions and the ongoing strengthening of the East Asian summer monsoon under global warming, our results highlight that a reevaluation of the contribution of Cl-VSLS injection via the Asian monsoon to the total stratospheric chlorine budget is warranted.

2.
Cells ; 12(21)2023 10 26.
Article in English | MEDLINE | ID: mdl-37947603

ABSTRACT

Cannabis is now one of the most commonly used illicit substances among pregnant women. This is particularly concerning since developmental exposure to cannabinoids can elicit enduring neurofunctional and cognitive alterations. This study investigates the mechanisms of learning and memory deficits resulting from prenatal cannabinoid exposure (PCE) in adolescent offspring. The synthetic cannabinoid agonist WIN55,212-2 was administered to pregnant rats, and a series of behavioral, electrophysiological, and immunochemical studies were performed to identify potential mechanisms of memory deficits in the adolescent offspring. Hippocampal-dependent memory deficits in adolescent PCE animals were associated with decreased long-term potentiation (LTP) and enhanced long-term depression (LTD) at hippocampal Schaffer collateral-CA1 synapses, as well as an imbalance between GluN2A- and GluN2B-mediated signaling. Moreover, PCE reduced gene and protein expression of neural cell adhesion molecule (NCAM) and polysialylated-NCAM (PSA-NCAM), which are critical for GluN2A and GluN2B signaling balance. Administration of exogenous PSA abrogated the LTP deficits observed in PCE animals, suggesting PSA mediated alterations in GluN2A- and GluN2B- signaling pathways may be responsible for the impaired hippocampal synaptic plasticity resulting from PCE. These findings enhance our current understanding of how PCE affects memory and how this process can be manipulated for future therapeutic purposes.


Subject(s)
Cannabinoids , Neural Cell Adhesion Molecules , Humans , Rats , Female , Animals , Pregnancy , Adolescent , Neural Cell Adhesion Molecules/metabolism , Cannabinoids/pharmacology , Cannabinoids/metabolism , Neuronal Plasticity/physiology , Hippocampus/metabolism , Memory Disorders/metabolism
3.
Ultrason Sonochem ; 100: 106625, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37801993

ABSTRACT

Ultrasonic dental scalers are indispensable instruments for efficient dental cleaning through the generation of cavitation. To gain valuable insights and enhance the cavitation cleaning effects, a numerical investigation is conducted using the finite element method via ABAQUS. Numerical results are compared with the experimental cavitation image for a scaler undergoes vibrations near a wall. We then analyse how the amplitude, frequency, and cross-sectional shape of the scaler affect cavitation generation. Numerical results indicate that cavitation is more pronounced for a scaler oscillating near a nearly rigid boundary than a soft boundary. It increases with the vibration amplitude because of higher ultrasonic energy transferring to the liquid and generating stronger pressure waves. The resonant frequency of the scaler coincides with the maximum cavitation and scaler tip amplitude. Reducing the dimension of the cross-section of the scaler in its oscillation direction increases both the scaler tip amplitude and the cavitation generated. This finding offers a potential design approach for enhancing the scaler cavitation and its cleaning effects. These insights provide practical guidance for optimising dental scaler settings, which can improve oral hygiene and prevent complications related to dental implants.


Subject(s)
Ultrasonic Therapy , Ultrasonics , Humans , Periodontal Pocket , Ultrasonics/methods , Vibration , Energy Transfer
4.
Ultrason Sonochem ; 90: 106178, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36194949

ABSTRACT

Periodontal pockets are spaces or holes surrounded by teeth under the gum line. These pockets can become filled with infection-causing bacteria resulting in tissue, bone, and tooth loss. Cavitation produced by the oscillating tip of dental ultrasonic scalers plays a significant role in routine periodontal therapy to clean these areas. Numerical studies were conducted for a scaler vibrating in a periodontal pocket which was simplified to a hole, using ABAQUS based on the finite element method. The simulations consider the three-dimensional, nonlinear, and transient interaction between the vibration and deformation of the scaler tip, the water flow around the scaler and the cavitation formation. The numerical model was validated by comparing results with experimental data for a scaler vibrating in an unbounded liquid, the displacement at the free end of the scaler and the cavitation pattern near the scaler tip displaying excellent agreement. A parametric study for a scaler vibrating in a hole has been carried out in terms of the volume of the hole, the taper ratio (the radius ratio between the circular opening and bottom of the hole), and the immersion depth of the scaler tip in the hole. The amount of cavitation generated is evaluated by the cavitation density (or the void fraction) which is the ratio of the volume of the cavitation occupied in the hole to the total volume of the hole. Numerical results indicate that the cavitation density in the hole increases with the decreasing hole volume and the increasing taper ratio. It is inferred that cleaning effects could be increased if some modifications to the scaler design could be made to increase the blocking effect of the hole during the cleaning process. Cavitation is observed in the hole even if the scaler is placed above the hole and increases with the immersion depth.


Subject(s)
Ultrasonics , Vibration , Humans , Periodontal Pocket , Ultrasonics/methods
5.
Chem Asian J ; 15(19): 3059-3081, 2020 Oct 01.
Article in English | MEDLINE | ID: mdl-32749069

ABSTRACT

Syntheses of a range of chemically well-defined oligopyrrole/benzenoid hybrids are described using tandem Suzuki-Miyaura cross-coupling/bromo-desilyation reaction sequences for linking borylated pyrroles, halogenated pyrroles and/or dibromobenzenes to one another. By such means, including iterative variants, a range of all α-linked, all ß-linked oligopyrroles as well as certain combinations thereof have been assembled, some of them for the first time. The conductivities of iodine-treated thin films formed from certain such systems have been determined.

6.
Patient Educ Couns ; 103(11): 2305-2311, 2020 11.
Article in English | MEDLINE | ID: mdl-32475712

ABSTRACT

OBJECTIVE: To determine if a novel interdisciplinary "speed-dating" clinic augments Diabetes Self-Management Education and Support (DSMES). METHODS: Adult patients with diabetes attended a DSMES class. Two weeks later patients attended an interdisciplinary clinic utilizing a "speed-dating" format during which they progressed through 5 stations hosted by different healthcare disciplines at 30-minute increments: physician, pharmacist, nurse/dietitian, case manager, and psychologist. Shared decision-making was utilized to identify mutually agreeable recommendations. Change in clinical outcomes were compared for DSMES-only attenders versus Dual-attendees; utilization of emergency department and hospital services were measured 12 months before and after attending the Speed Dating clinic. This analysis represents patients attending the program during 2016. RESULTS: Sixty-nine attended the DSMES class, 40 of whom followed-up in the "speed-dating" clinic (58% return rate). Attending the Speed Dating clinic improved A1C (p = 0.003) and LDL-C (p = 0.003) compared to the DSMES class alone. Comparatively, after attending the speed-dating clinic, patients had fewer emergency department (p = 0.366) and hospital admissions (p = 0.036), and shorter lengths of hospital stay (p = 0.030). CONCLUSIONS: The interdisciplinary "speed-dating" approach improved diabetes outcomes beyond DSMES alone and reduced utilization of hospital services. PRACTICE IMPLICATIONS: Patients should attend DSMES but also participate in an Interdisciplinary Speed Dating follow-up to further improve outcomes.


Subject(s)
Delivery of Health Care/methods , Diabetes Mellitus, Type 1/drug therapy , Diabetes Mellitus, Type 2/drug therapy , Hypoglycemic Agents/therapeutic use , Patient Care Team , Patient Education as Topic , Self Care , Self-Management/education , Adult , Aged , Case Managers , Diabetes Mellitus, Type 1/psychology , Diabetes Mellitus, Type 2/psychology , Female , Health Educators , Humans , Interdisciplinary Communication , Male , Middle Aged , Nutritionists , Outcome Assessment, Health Care , Pharmacists
7.
Article in English | MEDLINE | ID: mdl-31824431

ABSTRACT

Adiponectin is an adipokine that has recently been under investigation for potential neuroprotective effects in various brain disorders including Alzheimer's disease, stroke, and depression. Adiponectin receptors (AdipoR1 and AdipoR2) are found throughout various brain regions, including the hippocampus. However, the role of these receptors in synaptic and cognitive function is not clear. Therefore, the goal of the current study was to evaluate synaptic and cognitive function in the absence of adiponectin. The current study utilized 12-month-old adiponectin knockout (APN-KO) mice and age-matched controls to study cognitive and hippocampal synaptic alterations. We determined that AdipoR1 and AdipoR2 are present in the synaptosome, with AdipoR2 displaying increased presynaptic vs. postsynaptic localization, whereas AdipoR1 was enriched in both the presynaptic and postsynaptic fractions. APN-KO mice displayed cognitive deficits in the novel object recognition (NOR) and Y-maze tests. This was mirrored by deficits in long-term potentiation (LTP) of the hippocampal Schaefer collateral pathway in APN-KO mice. APN-KO mice also displayed a reduction in basal synaptic transmission and an increase in presynaptic release probability. Deficits in LTP were rescued through hippocampal slice incubation with the adiponectin receptor agonist, AdipoRon, indicating that acute alterations in adiponectin receptor signaling influence synaptic function. Along with the deficits in LTP, altered levels of key presynaptic and postsynaptic proteins involved in glutamatergic neurotransmission were observed in APN-KO mice. Taken together, these results indicate that adiponectin is an important regulator of cognition and synaptic function in the hippocampus. Future studies should examine the role of specific adiponectin receptors in synaptic processes.

8.
Sci Rep ; 9(1): 17136, 2019 11 20.
Article in English | MEDLINE | ID: mdl-31748625

ABSTRACT

Extreme flooding over southern Louisiana in mid-August of 2016 resulted from an unusual tropical low that formed and intensified over land. We used numerical experiments to highlight the role of the 'Brown Ocean' effect (where saturated soils function similar to a warm ocean surface) on intensification and it's modulation by land cover change. A numerical modeling experiment that successfully captured the flood event (control) was modified to alter moisture availability by converting wetlands to open water, wet croplands, and dry croplands. Storm evolution in the control experiment with wet antecedent soils most resembles tropical lows that form and intensify over oceans. Irrespective of soil moisture conditions, conversion of wetlands to croplands reduced storm intensity, and also, non-saturated soils reduced rain by 20% and caused shorter durations of high intensity wind conditions. Developing agricultural croplands and more so restoring wetlands and not converting them into open water can impede intensification of tropical systems that affect the area.

9.
10.
J Diabetes Metab Disord ; 18(1): 155-162, 2019 Jun.
Article in English | MEDLINE | ID: mdl-31275886

ABSTRACT

PURPOSE: Many patients are unknowingly living with chronic hyperglycemia, possibly due to low screening rates. We aimed to correlate detection of unidentified chronic hyperglycemia to practitioner reported rationale for conducting diabetes screening. METHODS: Physicians screened patients via a point-of-care A1C tests and recorded corresponding rationales. Elevated outcomes (A1C ≥ 5.7%) were correlated to recorded rationales, frequency of repeat screenings, documented diagnoses, and therapeutic actions taken as a result of elevated A1C. RESULTS: Nearly one-half (45%) of selected patients were unknowingly living with chronic hyperglycemia, having an average A1C of 7.92% for outcomes ≥6.5%. Most commonly recorded rationales were overweight status (71%), high-risk ethnicity (58%), and age > 45 years (48%); previously recorded A1C result of ≥5.7% (χ2 16.02, p < 0.001) and hypertension diagnosis (χ2 10.37, p = 0.0013) showed statistically significant correlation with elevated A1C outcomes. A1C results ≥6.5% versus 5.7-6.5% more frequently prompted repeat screenings (77% vs 20%), ICD-10 code documentation (91% vs 28%), lifestyle modification recommendations (78% vs 35%), and drug therapy initiation (78% vs 9%). CONCLUSIONS: Reported rationales were largely impacted by visual inspections of age, race, and weight, and prediabetic A1C values garnered less attention compared to higher values. Utilization of POC A1C screening followed by conformational repeat testing is a practical approach to improve diagnostic rates and initiation of care for diabetes.

11.
Neuropharmacology ; 149: 181-194, 2019 05 01.
Article in English | MEDLINE | ID: mdl-30771373

ABSTRACT

Marijuana is one of the most commonly used illicit drugs worldwide. In addition, use of synthetic cannabinoids is increasing, especially among adolescents and young adults. Although human studies have shown that the use of marijuana during pregnancy leads to adverse behavioral effects, such as deficiencies in attention and executive function in affected offspring, the rate of marijuana use among pregnant women is steadily increasing. Various aspects of human behavior including emotion, learning, and memory are dependent on complex interactions between multiple neurotransmitter systems that are especially vulnerable to alterations during the developmental period. Thus, exploration of neurotransmitter changes in response to prenatal cannabinoid exposure is crucial to develop an understanding of how homeostatic imbalance and various long-term neurobehavioral deficits manifest following the abuse of marijuana or other synthetic cannabinoids during pregnancy. Current literature confirms that vast alterations to neurotransmitter systems are present following prenatal cannabinoid exposure, and many of these alterations within the brain are region specific, time-dependent, and sexually dimorphic. In this review, we aim to provide a summary of observed changes to various neurotransmitter systems following cannabinoid exposure during pregnancy and to draw possible correlations to reported behavioral alterations in affected offspring.


Subject(s)
Cannabinoids/adverse effects , Cannabis/adverse effects , Pregnancy/drug effects , Prenatal Exposure Delayed Effects/physiopathology , Synaptic Transmission/drug effects , Adrenergic Neurons/drug effects , Animals , Brain/drug effects , Cannabinoids/pharmacology , Cognition Disorders , Dopaminergic Neurons/drug effects , Female , GABAergic Neurons/drug effects , Humans , Male , Problem Behavior , Serotonergic Neurons/drug effects , Sex Characteristics
12.
Neuronal Signal ; 3(2): NS20180203, 2019 06.
Article in English | MEDLINE | ID: mdl-32269835

ABSTRACT

Alzheimer's disease (AD) is the leading cause of dementia affecting almost 50 million people worldwide. The ε4 allele of Apolipoprotein E (APOE) is the strongest known genetic risk factor for late-onset AD cases, with homozygous APOE4 carriers being approximately 15-times more likely to develop the disease. With 25% of the population being APOE4 carriers, understanding the role of this allele in AD pathogenesis and pathophysiology is crucial. Though the exact mechanism by which ε4 allele increases the risk for AD is unknown, the processes mediated by APOE, including cholesterol transport, synapse formation, modulation of neurite outgrowth, synaptic plasticity, destabilization of microtubules, and ß-amyloid clearance, suggest potential therapeutic targets. This review will summarize the impact of APOE on neurons and neuronal signaling, the interactions between APOE and AD pathology, and the association with memory decline. We will then describe current treatments targeting APOE4, complications associated with the current therapies, and suggestions for future areas of research and treatment.

13.
PLoS One ; 13(4): e0196078, 2018.
Article in English | MEDLINE | ID: mdl-29672598

ABSTRACT

BACKGROUND: To review long QT syndrome molecular autopsy results in sudden unexplained death in young (SUDY) between 2006 and 2013 in New Zealand. METHODS: Audit of the LQTS molecular autopsy results, cardiac investigations and family screening data from gene-positive families. RESULTS: During the study period, 365 SUDY cases were referred for molecular autopsy. 128 cases (35%) underwent LQTS genetic testing. 31 likely pathogenic variants were identified in 27 cases (21%); SCN5A (14/31, 45%), KCNH2 (7/31, 22%), KCNQ1 (4/31, 13%), KCNE2 (3/31, 10%), KCNE1 (2/31, 7%), KCNJ2 (1/31, 3%). Thirteen variants (13/128, 10%) were ultimately classified as pathogenic. Most deaths (63%) occurred during sleep. Gene variant carriage was more likely with a positive medical history (mostly seizures, 63% vs 36%, p = 0.01), amongst females (36% vs 12%, p = 0.001) and whites more than Maori (31% vs 0, p = 0.0009). Children 1-12 years were more likely to be gene-positive (33% vs 14%, p = 0.02). Family screening identified 42 gene-positive relatives, 18 with definitive phenotypic expression of LQTS/Brugada. 76% of the variants were maternally inherited (p = 0.007). Further family investigations and research now support pathogenicity of the variant in 13/27 (48%) of gene-positive cases. CONCLUSION: In New Zealand, variants in SCN5A and KCNH2, with maternal inheritance, predominate. A rare variant in LQTS genes is more likely in whites rather than Maori, females, children 1-12 years and those with a positive personal and family history of seizures, syncope or SUDY. Family screening supported the diagnosis in a third of the cases. The changing classification of variants creates a significant challenge.


Subject(s)
Death, Sudden, Cardiac/epidemiology , Death, Sudden, Cardiac/etiology , Genetic Association Studies , Genetic Predisposition to Disease , Long QT Syndrome/genetics , Long QT Syndrome/physiopathology , Adolescent , Adult , Alleles , Amino Acid Substitution , Child , Child, Preschool , Female , Genotype , Humans , Infant , Long QT Syndrome/complications , Male , New Zealand/epidemiology , Young Adult
14.
Blood Transfus ; 16(1): 53-62, 2018 01.
Article in English | MEDLINE | ID: mdl-27893353

ABSTRACT

BACKGROUND: Jehovah's Witnesses who refuse blood transfusion have high mortality. Erythropoietin (EPO) has been used as an alternative to blood transfusion. The optimal dosing of EPO in anaemic Jehovah's Witnesses is unknown. The aim of our study was to evaluate the clinical benefits of treatment with a low dose (<600 IU/kg/week) of epoietin beta (EPO-ß). MATERIALS AND METHODS: This was an observational study, retrospectively considering a 10-year period during which 3,529 adult Jehovah's Witnesses with a total of 10,786 hospital admissions were identified from databases of four major public hospitals in New Zealand. Patients with severe symptomatic anaemia (haemoglobin <80 g/L) who were unable to tolerate physical activity were included in the study. Patients treated without EPO were assigned to the conventional therapy group and those treated with EPO to the EPO treatment group. RESULTS: Ninety-one Jehovah's Witnesses met the eligibility criteria. Propensity score matching yielded a total of 57 patients. Patients treated with conventional therapy and those treated with EPO had similar durations of severe anaemia (average difference 6.25 days, 95% confidence interval [CI]: -3.77-16.27 days; p=0.221). The mortality rate among Jehovah's Witnesses treated with conventional therapy was 4.68 per year (95% CI: 2.23-9.82), while that in those treated with EPO was 2.77 per year (95% CI: 0.89-8.60). Treatment with EPO was associated with a mortality ratio of 0.59 (95% CI: 0.1-2.6; p=0.236). Both groups of patients had similar in-hospital survival (p=0.703). DISCUSSION: Treatment with low-dose EPO-ß was not associated with either shorter duration of severe anaemia or a reduction in mortality.


Subject(s)
Anemia/drug therapy , Databases, Factual , Erythropoietin/administration & dosage , Jehovah's Witnesses , Adult , Aged , Anemia/blood , Anemia/mortality , Disease-Free Survival , Erythropoietin/adverse effects , Female , Humans , Male , Middle Aged , Retrospective Studies , Survival Rate
15.
Am Heart J ; 185: 67-73, 2017 Mar.
Article in English | MEDLINE | ID: mdl-28267477

ABSTRACT

BACKGROUND: To compare simultaneous recordings from an external patch system specifically designed to ensure better P-wave recordings and standard Holter monitor to determine diagnostic efficacy. Holter monitors are a mainstay of clinical practice, but are cumbersome to access and wear and P-wave signal quality is frequently inadequate. METHODS: This study compared the diagnostic efficacy of the P-wave centric electrocardiogram (ECG) patch (Carnation Ambulatory Monitor) to standard 3-channel (leads V1, II, and V5) Holter monitor (Northeast Monitoring, Maynard, MA). Patients were referred to a hospital Holter clinic for standard clinical indications. Each patient wore both devices simultaneously and served as their own control. Holter and Patch reports were read in a blinded fashion by experienced electrophysiologists unaware of the findings in the other corresponding ECG recording. All patients, technicians, and physicians completed a questionnaire on comfort and ease of use, and potential complications. RESULTS: In all 50 patients, the P-wave centric patch recording system identified rhythms in 23 patients (46%) that altered management, compared to 6 Holter patients (12%), P<.001. The patch ECG intervals PR, QRS and QT correlated well with the Holter ECG intervals having correlation coefficients of 0.93, 0.86, and 0.94, respectively. Finally, 48 patients (96%) preferred wearing the patch monitor. CONCLUSIONS: A single-channel ambulatory patch ECG monitor, designed specifically to ensure that the P-wave component of the ECG be visible, resulted in a significantly improved rhythm diagnosis and avoided inaccurate diagnoses made by the standard 3-channel Holter monitor.


Subject(s)
Arrhythmias, Cardiac/diagnosis , Electrocardiography, Ambulatory/instrumentation , Syncope/diagnosis , Adult , Aged , Arrhythmias, Cardiac/complications , Electrocardiography/instrumentation , Electrocardiography/methods , Electrocardiography, Ambulatory/methods , Electrodes , Female , Humans , Male , Middle Aged , Patient Preference , Prospective Studies , Syncope/etiology
16.
Article in English | MEDLINE | ID: mdl-27516460

ABSTRACT

BACKGROUND: Long-term uninterrupted ß-blockade significantly reduces cardiac events in long QT syndrome (LQTS). Despite this, data on nonadherence are scarce and quantified only on the day of cardiac arrest in LQTS literature. We aimed to describe ß-blocker adherence, and predictors thereof, among patients with LQTS types 1 and 2. METHODS AND RESULTS: Electronic health records and pharmacy dispensing data were reviewed for 90 patients with LQTS 1 and 2 who reside in Auckland, New Zealand, during a 34-month period. For each patient, the medication possession ratio (MPR: proportion of follow-up days patients were dispensed ß-blocker) was calculated. Adequate adherence was characterized by an MPR ≥0.8 and ideal as MPR=1.0. Clinical and demographic features were assessed to determine whether they predicted adherence. Long-term ß-blockers were prescribed to 74 patients (82%). Side effects were described as intolerable by 6 (8%) and their ß-blockers were stopped. MPR was calculated in the remaining 68 patients >151.7 patient-years of follow-up. Median MPR was 0.79 (range, 0-1.3). Suboptimal adherence (MPR<0.8) was recorded in 35 (51%). Seven patients (10%) never took up a prescription (MPR=0). Adequate adherence was present in 33 (49%), including 9 (13%) who had ideal adherence. Age, sex, clinical presentation, family history of sudden death, ethnicity, and deprivation index did not predict adherence. CONCLUSIONS: Adherence to ß-blockers in LQTS is suboptimal in half of those with LQTS 1 and 2. Risk factors for nonadherence could not be identified in our population. Further research into ß-blocker adherence is imperative in this high-risk population.


Subject(s)
Adrenergic beta-Antagonists/therapeutic use , Long QT Syndrome/drug therapy , Medication Adherence , Adolescent , Adult , Female , Humans , Long QT Syndrome/genetics , Male , Middle Aged , New Zealand , Risk Factors
17.
Heart Lung Circ ; 25(3): 275-81, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26546095

ABSTRACT

BACKGROUND: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is associated with a high incidence of ventricular tachyarrhythmia and sudden death. The mainstay of management is the implantable cardioverter defibrillator (ICD). A small number of patient cohorts have generated a large number of reports. METHODS: Prospective registry data supplemented with clinical and ICD records of 30 patients with ARVC fulfilling the 2010 modified Task Force Criteria. This cohort has not been reported on previously. RESULTS: Median age at diagnosis: 46yrs (range 21-68); 20 (80%) male; six (19%) Maori. Duration of follow-up: 7.4yrs (range 1.7-23). Implantable cardioverter defibrillator implantation in 26; three (12%) for resuscitated sudden cardiac death; 17 (65%) for symptomatic ventricular tachyarrhythmia; three (12%) for syncope; and three (12%) for family history of sudden death attributable to ARVC. Two patients died during follow-up, one had an ICD, though died of a carcinoma. Thirteen (50%) experienced appropriate ICD therapy with median time to therapy 12 months, and four (15%) experienced inappropriate shock therapy. Male gender was an independent predictor of appropriate ICD therapy (HR 1.6, 95% CI 1.5-2.7, P=0.01). CONCLUSIONS: The long-term prognosis of patients with ARVC is favourable although high proportions receive appropriate ICD therapy. Male gender is an independent predictor of appropriate ICD therapy.


Subject(s)
Arrhythmias, Cardiac/diagnosis , Arrhythmias, Cardiac/mortality , Cost of Illness , Hypertrophy, Right Ventricular/diagnosis , Hypertrophy, Right Ventricular/therapy , Registries , Adult , Aged , Arrhythmias, Cardiac/therapy , Defibrillators, Implantable , Female , Follow-Up Studies , Humans , Hypertrophy, Right Ventricular/mortality , Male , Middle Aged , Prognosis , Prospective Studies , Sex Factors
18.
J Cardiovasc Electrophysiol ; 26(12): 1346-51, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26332198

ABSTRACT

INTRODUCTION: The accurate prediction of the risk of sudden cardiac death (SCD) in hypertrophic cardiomyopathy (HCM) remains elusive. Corrected QT interval (QTc) duration is a known risk factor in various cardiac conditions. Single nucleotide polymorphisms (SNPs) have been linked to QTc length, and to SCD. Here we investigated the role of 21 candidate SNPs in QTc duration and SCD events in patients with HCM. METHODS AND RESULTS: This HCM registry-based study included patients with an ECG, medical history, first SCD event data, and DNA available. Each individual SNP was assessed using logistic regression for associations with 2 outcomes: a prolonged QTc ( ≥440 milliseconds), and first SCD event (SCD, resuscitated cardiac arrest, and appropriate implantable cardioverter defibrillator (ICD) shock for ventricular fibrillation/ventricular tachycardia (VF/VT). In 272 HCM patients, there were 31 SCD events (8 SCD, 9 resuscitated cardiac arrest, 14 ICD shocks for VF/VT; 11%). A QTc ≥ 500 milliseconds was associated with SCD events on multivariate analysis (odds ratio [OR] = 4.0, 95% confidence interval [CI], 1.19-12.02, P = 0.016). In 228 Caucasian patients, 2 SNPs in the NOS1AP gene (rs10494366 and rs12143842) were associated with a prolonged QTc after correction for multiple testing. This remained significant after adjustment for current age, sex, and ≥1 SCD risk factor (OR 1.59 per copy of the minor allele, 95% CI 1.08-2.39, P = 0.022, and OR 1.63, 95% CI 1.09-2.49, P = 0.020, respectively). No SNPs were directly associated with SCD events. CONCLUSION: SNPs in the NOS1AP gene influence QTc interval duration but we have not demonstrated a direct association with the risk of SCD.


Subject(s)
Adaptor Proteins, Signal Transducing/genetics , Cardiomyopathy, Hypertrophic/genetics , Cardiomyopathy, Hypertrophic/physiopathology , Heart Arrest/etiology , Heart Arrest/genetics , Long QT Syndrome/genetics , Long QT Syndrome/physiopathology , Aged , Cardiomyopathy, Hypertrophic/epidemiology , Cohort Studies , DNA/genetics , Death, Sudden, Cardiac , Defibrillators, Implantable , Electrocardiography , Female , Heart Arrest/epidemiology , Humans , Long QT Syndrome/epidemiology , Male , Middle Aged , New Zealand/epidemiology , Polymorphism, Single Nucleotide , Risk , Treatment Outcome
19.
J Hazard Mater ; 283: 164-70, 2015.
Article in English | MEDLINE | ID: mdl-25262487

ABSTRACT

In this paper, we demonstrate conducting polypyrrole films as a potential green technology for electrochemical treatment of azo dyes in wastewaters using Acid Red 1 as a model analyte. These films were synthesised by anodically polymerising pyrrole in the presence of Acid Red 1 as a supporting electrolyte. In this way, the anionic Acid Red 1 is electrostatically attracted to the cationic polypyrrole backbone formed to maintain electroneutrality, and is thus entrapped in the film. These Acid Red 1-entrapped polypyrrole films were characterised by electrochemical, microscopic and spectroscopic techniques. Based on a two-level factorial design, the solution pH, Acid Red 1 concentration and polymerisation duration were identified as significant parameters affecting the entrapment efficiency. The entrapment process will potentially aid in decolourising Acid Red 1-containing wastewaters. Similarly, in a cathodic process, electrons are supplied to neutralise the polypyrrole backbone, liberating Acid Red 1 into a solution. In this work, following an entrapment duration of 480 min in 2000 mg L(-1) Acid Red 1, we estimated 21% of the dye was liberated after a reduction period of 240 min. This allows the recovery of Acid Red 1 for recycling purposes. A distinctive advantage of this electrochemical Acid Red 1 treatment, compared to many other techniques, is that no known toxic by-products are generated in the treatment. Therefore, conducting polypyrrole films can potentially be applied as an environmentally friendly treatment method for textile effluents.


Subject(s)
Azo Compounds/analysis , Industrial Waste , Polymers/chemistry , Pyrroles/chemistry , Textiles , Waste Disposal, Fluid/methods , Wastewater/chemistry , Water Pollutants, Chemical/chemistry , Azo Compounds/chemistry , Water Pollutants, Chemical/analysis
20.
Heart Rhythm ; 11(8): 1352-8, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24732366

ABSTRACT

BACKGROUND: The subcutaneous implantable cardioverter-defibrillator system (S-ICD) uses a novel detection algorithm previously shown to discriminate induced tachyarrhythmias (ventricular vs supraventricular) effectively. OBJECTIVE: The purpose of this study was to evaluate the role of the S-ICD discrimination algorithm in reducing the incidence of spontaneous inappropriate shocks. METHODS: A total of 314 subjects underwent implantation with an S-ICD system as part of the S-ICD Clinical Investigation (IDE Trial). Subjects were grouped according to programming at discharge to either a single shock zone or 2 shock zones, with a discrimination algorithm in the lower rate zone. RESULTS: This cohort had 226 subjects (72%) with dual zone programming and 88 subjects (28%) with single zone programming. Over a mean follow-up period of 661 ± 174 days, inappropriate shocks occurred in 23 subjects from the dual zone subgroup (10.2%) and 23 subjects from the single zone subgroup (26.1%, P < .001), with 2-year inappropriate shock-free rates of 89.7% vs. 73.6%;,respectively (hazard ratio 0.38, P = .001). Freedom from appropriate shocks did not differ between subgroups (92.2% vs. 90.3%, hazard ratio 0.82, P = .64). Moreover, mean time to appropriate therapy did not differ between subgroups, and there was only 1 episode of arrhythmic syncope in the cohort. CONCLUSION: The addition of a second shock zone with an active discrimination algorithm was strongly associated with a reduction in inappropriate shocks with the S-ICD system and did not result in prolongation of detection times or increased syncope. These data support the use of dual zone programming as a standard setting for S-ICD patients.


Subject(s)
Algorithms , Defibrillators, Implantable/standards , Electric Countershock/methods , Tachycardia, Ventricular/therapy , Electric Countershock/standards , Electrocardiography , Equipment Failure , Female , Follow-Up Studies , Humans , Male , Middle Aged , Prospective Studies , Tachycardia, Ventricular/physiopathology , Treatment Outcome
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