Novel non-invasive algorithm to identify the origins of re-entry and ectopic foci in the atria from 64-lead ECGs: A computational study.

Atrial tachy-arrhytmias, such as atrial fibrillation (AF), are characterised by irregular electrical activity in the atria, generally associated with erratic excitation underlain by re-entrant scroll waves, fibrillatory conduction of multiple wavelets or rapid focal activity. Epidemiological studies have shown an increase in AF prevalence in the developed world associated with an ageing society, highlighting the need for effective treatment options. Catheter ablation therapy, commonly used in the treatment of AF, requires spatial information on atrial electrical excitation. The standard 12-lead electrocardiogram (ECG) provides a method for non-invasive identification of the presence of arrhythmia, due to irregularity in the ECG signal associated with atrial activation compared to sinus rhythm, but has limitations in providing specific spatial information. There is therefore a pressing need to develop novel methods to identify and locate the origin of arrhythmic excitation. Invasive methods provide direct information on atrial activity, but may induce clinical complications. Non-invasive methods avoid such complications, but their development presents a greater challenge due to the non-direct nature of monitoring. Algorithms based on the ECG signals in multiple leads (e.g. a 64-lead vest) may provide a viable approach. In this study, we used a biophysically detailed model of the human atria and torso to investigate the correlation between the morphology of the ECG signals from a 64-lead vest and the location of the origin of rapid atrial excitation arising from rapid focal activity and/or re-entrant scroll waves. A focus-location algorithm was then constructed from this correlation. The algorithm had success rates of 93% and 76% for correctly identifying the origin of focal and re-entrant excitation with a spatial resolution of 40 mm, respectively. The general approach allows its application to any multi-lead ECG system. This represents a significant extension to our previously developed algorithms to predict the AF origins in association with focal activities

Cross-protection against European swine influenza viruses in the context of infection immunity against the 2009 pandemic H1N1 virus : studies in the pig model of influenza

Pigs are natural hosts for the same influenza virus subtypes as humans and are a valuable model for cross-protection studies with influenza. In this study, we have used the pig model to examine the extent of virological protection between a) the 2009 pandemic H1N1 (pH1N1) virus and three different European H1 swine influenza virus (SIV) lineages, and b) these H1 viruses and a European H3N2 SIV. Pigs were inoculated intranasally with representative strains of each virus lineage with 6- and 17-week intervals between H1 inoculations and between H1 and H3 inoculations, respectively. Virus titers in nasal swabs and/or tissues of the respiratory tract were determined after each inoculation. There was substantial though differing cross-protection between pH1N1 and other H1 viruses, which was directly correlated with the relatedness in the viral hemagglutinin (HA) and neuraminidase (NA) proteins. Cross-protection against H3N2 was almost complete in pigs with immunity against H1N2, but was weak in H1N1/pH1N1-immune pigs. In conclusion, infection with a live, wild type influenza virus may offer substantial cross-lineage protection against viruses of the same HA and/or NA subtype. True heterosubtypic protection, in contrast, appears to be minimal in natural influenza virus hosts. We discuss our findings in the light of the zoonotic and pandemic risks of SIVs

Survivors of intensive care with type 2 diabetes and the effect of shared care follow-up clinics: study protocol for the SWEET-AS randomised controlled feasibility study

Published online: 13 October 2016Background: Many patients who survive the intensive care unit (ICU) experience long-term complications such as peripheral neuropathy and nephropathy which represent a major source of morbidity and affect quality of life adversely. Similar pathophysiological processes occur frequently in ambulant patients with diabetes mellitus who have never been critically ill. Some 25 % of all adult ICU patients have diabetes, and it is plausible that ICU survivors with co-existing diabetes are at heightened risk of sequelae from their critical illness. ICU follow-up clinics are being progressively implemented based on the concept that interventions provided in these clinics will alleviate the burdens of survivorship. However, there is only limited information about their outcomes. The few existing studies have utilised the expertise of healthcare professionals primarily trained in intensive care and evaluated heterogenous cohorts. A shared care model with an intensivist- and diabetologist-led clinic for ICU survivors with type 2 diabetes represents a novel targeted approach that has not been evaluated previously. Prior to undertaking any definitive study, it is essential to establish the feasibility of this intervention. Methods: This will be a prospective, randomised, parallel, open-label feasibility study. Eligible patients will be approached before ICU discharge and randomised to the intervention (attending a shared care follow-up clinic 1 month after hospital discharge) or standard care. At each clinic visit, patients will be assessed independently by both an intensivist and a diabetologist who will provide screening and targeted interventions. Six months after discharge, all patients will be assessed by blinded assessors for glycated haemoglobin, peripheral neuropathy, cardiovascular autonomic neuropathy, nephropathy, quality of life, frailty, employment and healthcare utilisation. The primary outcome of this study will be the recruitment and retention at 6 months of all eligible patients. Discussion: This study will provide preliminary data about the potential effects of critical illness on chronic glucose metabolism, the prevalence of microvascular complications, and the impact on healthcare utilisation and quality of life in intensive care survivors with type 2 diabetes. If feasibility is established and point estimates are indicative of benefit, funding will be sought for a larger, multi-centre study. Trial registration: ANZCTR ACTRN12616000206426Yasmine Ali Abdelhamid, Liza Phillips, Michael Horowitz and Adam Dean

The impact of socio-economic disadvantage on rates of hospital separations for diabetes-related foot disease in Victoria, Australia

<p>Abstract</p> <p>Background</p> <p>Information describing variation in health outcomes for individuals with diabetes related foot disease, across socioeconomic strata is lacking. The aim of this study was to investigate variation in rates of hospital separations for diabetes related foot disease and the relationship with levels of social advantage and disadvantage.</p> <p>Methods</p> <p>Using the Index of Relative Socioeconomic Disadvantage (IRSD) each local government area (LGA) across Victoria was ranked from most to least disadvantaged. Those LGAs ranked at the lowest end of the scale and therefore at greater disadvantage (Group D) were compared with those at the highest end of the scale (Group A), in terms of total and per capita hospital separations for peripheral neuropathy, peripheral vascular disease, foot ulceration, cellulitis and osteomyelitis and amputation. Hospital separations data were compiled from the Victorian Admitted Episodes Database.</p> <p>Results</p> <p>Total and per capita separations were 2,268 (75.3/1,000 with diabetes) and 2,734 (62.3/1,000 with diabetes) for Group D and Group A respectively. Most notable variation was for foot ulceration (Group D, 18.1/1,000 <it>versus </it>Group A, 12.7/1,000, rate ratio 1.4, 95% CI 1.3, 1.6) and below knee amputation (Group D 7.4/1,000 <it>versus </it>Group A 4.1/1,000, rate ratio 1.8, 95% CI 1.5, 2.2). Males recorded a greater overall number of hospital separations across both socioeconomic strata with 66.2% of all separations for Group D and 81.0% of all separations for Group A recorded by males. However, when comparing mean age, males from Group D tended to be younger compared with males from Group A (mean age; 53.0 years <it>versus </it>68.7 years).</p> <p>Conclusion</p> <p>Variation appears to exist for hospital separations for diabetes related foot disease across socioeconomic strata. Specific strategies should be incorporated into health policy and planning to combat disparities between health outcomes and social status.</p

The Prostate Care Questionnaire for Carers (PCQ-C): reliability, validity and acceptability

<p>Abstract</p> <p>Background</p> <p>Patient experience is commonly monitored in evaluating and improving health care, but the experience of carers (partners/relatives/friends) is rarely monitored even though the role of carers can often be substantial. For carers to fulfil their role it is necessary to address their needs. This paper describes an evaluation of the reliability, validity and acceptability of the PCQ-C, a newly developed instrument designed to measure the experiences of carers of men with prostate cancer.</p> <p>Methods</p> <p>The reliability, acceptability and validity of the PCQ-C were tested through a postal survey and interviews with carers. The PCQ-C was posted to 1087 prostate cancer patients and patients were asked to pass the questionnaire on to their carer. Non-responders received one reminder. To assess test-retest reliability, 210 carers who had responded to the questionnaire were resent it a second time three weeks later. A subsample of nine carers from patients attending one hospital took part in qualitative interviews to assess validity and acceptability of the PCQ-C. Acceptability to service providers was evaluated based on four hospitals' experiences of running a survey using the PCQ-C.</p> <p>Results</p> <p>Questionnaires were returned by 514 carers (47.3%), and the majority of questions showed less than 10% missing data. Across the sections of the questionnaire internal consistency was high (Cronbach's alpha ranging from 0.80 to 0.89), and test-retest stability showed moderate to high stability (intraclass correlation coefficients ranging from 0.52 to 0.83). Interviews of carers indicated that the PCQ-C was valid and acceptable. Feedback from hospitals indicated that they found the questionnaire useful, and highlighted important considerations for its future use as part of quality improvement initiatives.</p> <p>Conclusions</p> <p>The PCQ-C has been found to be acceptable to carers and service providers having been used successfully in hospitals in England. It is ready for use to measure the aspects of care that need to be addressed to improve the quality of prostate cancer care, and for research.</p

Dose-Response Aligned Circuits in Signaling Systems

Cells use biological signal transduction pathways to respond to environmental stimuli and the behavior of many cell types depends on precise sensing and transmission of external information. A notable property of signal transduction that was characterized in the Saccharomyces cerevisiae yeast cell and many mammalian cells is the alignment of dose-response curves. It was found that the dose response of the receptor matches closely the dose responses of the downstream. This dose-response alignment (DoRA) renders equal sensitivities and concordant responses in different parts of signaling system and guarantees a faithful information transmission. The experimental observations raise interesting questions about the nature of the information transmission through DoRA signaling networks and design principles of signaling systems with this function. Here, we performed an exhaustive computational analysis on network architectures that underlie the DoRA function in simple regulatory networks composed of two and three enzymes. The minimal circuits capable of DoRA were examined with Michaelis-Menten kinetics. Several motifs that are essential for the dynamical function of DoRA were identified. Systematic analysis of the topology space of robust DoRA circuits revealed that, rather than fine-tuning the network's parameters, the function is primarily realized by enzymatic regulations on the controlled node that are constrained in limiting regions of saturation or linearity

A qualitative study of patients' views on quality of primary care consultations in Hong Kong and comparison with the UK CARE Measure

&lt;b&gt;Background&lt;/b&gt; Patients' priorities and views on quality care are well-documented in Western countries but there is a dearth of research in this area in the East. The aim of the present study was to explore Chinese patients' views on quality of primary care consultations in Hong Kong and to compare these with the items in the CARE measure (a process measure of consultation quality widely used in the UK) in order to assess the potential utility of the CARE measure in a Chinese population.&lt;p&gt;&lt;/p&gt; &lt;b&gt;Methods&lt;/b&gt; Individual semi-structured interviews were conducted on 21 adult patients from 3 different primary care clinics (a public primary healthcare clinic, a University health centre, and a private family physician's clinic). Topics discussed included expectations, experiences, and views about quality of medical consultations. Interviews were typed verbatim, and a thematic approach was taken to identify key issues. These identified issues were then compared with the ten CARE measure items, using a CARE framework: Connecting (Care Measure items 1–3), Assessing (item 4), Responding (items 5,6), and Empowering (items 7–10).&lt;p&gt;&lt;/p&gt; &lt;b&gt;Results&lt;/b&gt; Patients judged doctors in terms of both the process of the consultation and the perceived outcomes. Themes identified that related to the interpersonal process of the consultation fitted well under the CARE framework; Connecting and communicating (18/21 patients), Assessing holistically (10/21 patients), Responding (18/21 patients) and Empowering (19/21 patients). Patients from the public clinic, who were generally of lower socio-economic status, were least likely to expect holistic care or empowerment. Two-thirds of patients also judged doctors on whether they performed an adequate physical examination, and three-quarters on the later outcomes of consultation (in terms of relief or cure and/or side-effects of prescribed drugs).&lt;p&gt;&lt;/p&gt; &lt;b&gt;Conclusion&lt;/b&gt; These findings suggest that Chinese patients in Hong Kong value engaged, empathic primary care doctors and judge the quality of consultations largely on these human skills and the attitudes and values that underpin them, as well as on the perceived outcomes of treatment. The match between themes relating to consultation process and the CARE Measure items suggests utility of this measure in this population, but further quantitative validation is required

A Review on the Oral Health Impacts of Acculturation

The impact of acculturation on systemic health has been extensively investigated and is regarded as an important explanatory factor for health disparity. However, information is limited and fragmented on the oral health implications of acculturation. This study aimed to review the current evidence on the oral health impact of acculturation. Papers were retrieved from five electronic databases. Twenty-seven studies were included in this review. Their scientific quality was rated and key findings were summarized. Seventeen studies investigated the impacts of acculturation on the utilization of dental services; among them, 16 reported positive associations between at least one acculturation indicator and use of dental services. All 15 studies relating acculturation to oral diseases (dental caries and periodontal disease) suggested better oral health among acculturated individuals. Evidence is lacking to support that better oral health of acculturated immigrants is attributable to their improved dental attendance. Further researches involving other oral health behaviors and diseases and incorporating refined acculturation scales are needed. Prospective studies will facilitate the understanding on the trajectory of immigrants’ oral health along the acculturation continuum

The influence of behavioural and health problems on alcohol and drug use in late adolescence - a follow up study of 2 399 young Norwegians

<p>Abstract</p> <p>Background</p> <p>Both early alcohol debut, behavioural and health problems are reported to enhance adolescence substance use. This prospective study investigate the influence of behavioural and health problems on adolescents' alcohol and drug use.</p> <p>Method</p> <p>Prospective population based cohort study of 2 399 adolescents attending the Young-HUNT study, aged 13-15 at baseline in 1995/97, and 17-19 at follow-up 4 years later. Exposure variables were self reported conduct problems, attention problems, anxiety and depressive symptoms, and muscular pain and tension. Outcome variables at follow-up were frequent alcohol use and initiation of drug use. Associations were estimated by logistic regression models, influence of gender and drinking status at baseline were controlled for by stratification.</p> <p>Results</p> <p>At follow-up 19% of the students drank alcohol once a week or more frequently. Baseline conduct problems (OR 2.2, CI 1.7-3.0) and attention problems (OR 1.5, CI 1.2-2.0) increased the risk for frequent alcohol use at follow-up in the total population. Girls who had experienced alcohol-intoxications at baseline showed strong association between baseline problems and frequent alcohol use at follow-up. Conduct problems (OR 2.5, CI 1.3-4.8), attention problems (OR 2.1, CI 1.2-3.4), anxiety/depressive symptoms (OR 1.9, CI 1.1-3.1) and muscular pain and tension (OR 1.7, CI 1.0-2.9) all were associated with frequent alcohol use among early intoxicated girls.</p> <p>14% of the students had tried cannabis or other drugs at follow-up. Conduct problems at baseline increased the odds for drug use (OR 2.6, CI 1.9-3.6). Any alcohol intoxications at baseline, predicted both frequent alcohol use (boys OR 3.6, CI 2.4-5.2; girls OR 2.8, CI 1.9-4.1), and illegal drug use (boys OR 4.7; CI 3.2-7.0, girls OR 7.7, CI 5.2-11.5) within follow-up.</p> <p>Conclusions</p> <p>Conduct problems in high-school more than doubles the risk for both frequent alcohol use and initiation of drug use later in adolescence. The combination of health problems and alcohol intoxication in early adolescence was closely associated with more frequent drinking later in adolescence among girls.</p> <p>Overall, early alcohol intoxication was closely associated with both frequent alcohol use and drug use at follow up in both genders</p

Trajectories of maternal symptoms of anxiety and depression. A 13-year longitudinal study of a population-based sample

<p>Abstract</p> <p>Background</p> <p>There is a lack of population-based studies of developmental trajectories following mothers throughout the whole child-rearing phase and there are few longitudinal studies focusing on both symptoms of depression and anxiety. The aim of the current study is to identify latent trajectory groups based on counts of symptoms of anxiety and depression among mothers throughout the child-rearing phase and the relations of the latent groups to maternal socio-demographic variables.</p> <p>Methods</p> <p>Data is from a prospective, longitudinal study of nearly 1000 families in Norway followed from when the index children were 18 months until they were 14.5 years old (the TOPP study). The study used latent profile analysis (LPA) to identify latent groups of mothers with distinct trajectories across time of symptom counts. Latent group differences on socio-demographic variables were tested with one-way ANOVAs, chi-square tests and exact tests.</p> <p>Results</p> <p>Six trajectories based on maternal scores from six waves of data collection of symptoms of anxiety and depression were identified; a 'No symptoms' group with mothers without symptoms; a 'Low' group with mothers reporting low symptom levels; a 'Moderate-low' group with mothers reporting moderately low symptom levels; a 'Moderate' group with mothers with moderate symptoms; a 'High-chronic' group with mothers with overall high symptom levels; and a 'Low-rising' group with mothers starting with a low symptom level that increased over time. The mothers in the High-chronic symptom group differed from the other mothers on several socio-demographic variables. They were significantly younger than the mothers in the Low group comprising the oldest mothers. The mothers in the High-chronic group had significantly lower education, were less likely to have paid work and were less likely to be living with a partner than the mothers in the other groups.</p> <p>Conclusions</p> <p>The study shows socio-demographic differences between mothers classified into six trajectory groups based on symptoms of anxiety and depression covering 13 years of the child-rearing period. Specific socio-demographic risk factors characterised mothers in the High-chronic symptom group. Identifying subgroups with enduring problems might inform more targeted preventive efforts.</p