Enhancing the efficiency and cost-effectiveness of magnetocardiography by optimal channel selection for cardiac diagnosis.

Background. Magnetocardiography (MCG) is a non-invasive and non-contact technique that measures weak magnetic fields generated by the heart. It is highly effective in the diagnosis of heart abnormalities. Multichannel MCG provides detailed spatio-temporal information of the measured magnetic fields. While multichannel MCG systems are costly, usage of the optimal number of measurement channels to characterize cardiac magnetic fields without any appreciable loss of signal information would be economically beneficial and promote the widespread use of MCG technology.Methods. An optimization method based on the sequential selection approach is used to choose channels containing the maximum signal information while avoiding redundancy. The study comprised 40 healthy individuals, along with two subjects having ischemic heart disease and one subject with premature ventricular contraction. MCG measured using a 37 channel MCG system. After revisiting the existing methods of optimization, the mean error and correlation of the optimal set of measurement channels with those of all 37 channels are evaluated for different sets, and it has been found that 18 channels are adequate.Results. The chosen 18 optimal channels exhibited a strong correlation (0.99 ± 0.006) between the original and reconstructed magnetic field maps for a cardiac cycle in healthy subjects. The root mean square error is 0.295 pT, indicating minimal deviation.Conclusion. This selection method provides an efficient approach for choosing MCG, which could be used for minimizing the number of channels as well as in practical unforeseen measurement conditions where few channels are noisy during the measurement.

Comparison of different QT correction methods for nonclinical safety assessment in ketamine-anesthetized Indian rhesus monkeys (Macaca mulatta).

Rhesus monkeys are a non-rodent species employed in the preclinical safety evaluation of pharmaceuticals and biologics. These nonhuman primate species have been increasingly used in biomedical research because of the similarity in their ionic mechanisms of repolarization with humans. Heart rate and QT interval are two primary endpoints in determining the pro-arrhythmic risk of drugs. As heart rate and QT interval have an inverse relationship, any change in heart rate causes a subsequent change in QT interval. This warrants for calculation of a corrected QT interval. This study aimed to identify an appropriate formula that best corrected QT for change in heart rate. We employed seven formulas based on source-species type, clinical relevance, and requirements of various international regulatory guidelines. Data showed that corrected QT interval values varied drastically for different correction formulas. Equations were compared on their slope values based on QTc versus RR plots. The rank order of the slope for different formulas was (closest to farthest from zero) QTcNAK, QTcHAS, QTcBZT, QTcFRD, QTcVDW, QTcHDG, and QTcFRM. QTcNAK emerged to be the best correcting formula in this study. It showed the least correlation with the RR interval (r = -0.01) and displayed no significant difference amongst the sexes. As there is no universally recognized formula for preclinical use, the authors recommend developing a best-case scenario model for specific study designs and individual organizations. The data from this research will be helpful in deciding an appropriate QT correction formula for the safety assessment of new pharmaceuticals and biologics.

A Health System-Wide Initiative to Decrease Opioid-Related Morbidity and Mortality.

BACKGROUND: The opioid overdose crisis now claims more than 40,000 lives in the United States every year, and many hospitals and health systems are responding with opioid-related initiatives, but how best to coordinate hospital or health system-wide strategy and approach remains a challenge. METHODS: An organizational opioid stewardship program (OSP) was created to reduce opioid-related morbidity and mortality in order to provide an efficient, comprehensive, multidisciplinary approach to address the epidemic in one health system. An executive committee of hospital leaders was convened to empower and launch the program. To measure progress, metrics related to care of patients on opioids and those with opioid use disorder (OUD) were evaluated. RESULTS: The OSP created a holistic, health system-wide program that addressed opioid prescribing, treatment of OUD, education, and information technology tools. After implementation, the number of opioid prescriptions decreased (-73.5/month; p < 0.001), mean morphine milligram equivalents (MME) per prescription decreased (-0.4/month; p < 0.001), the number of unique patients receiving an opioid decreased (-52.6/month; p < 0.001), and the number of prescriptions ≥ 90 MME decreased (-48.1/month; p < 0.001). Prescriptions and providers for buprenorphine increased (+6.0 prescriptions/month and +0.4 providers/month; both p < 0.001). Visits for opioid overdose did not change (-0.2 overdoses/month; p = 0.29). CONCLUSION: This paper describes a framework for a new health system-wide OSP. Successful implementation required strong executive sponsorship, ensuring that the program is not housed in any one clinical department in the health system, creating an environment that empowers cross-disciplinary collaboration and inclusion, as well as the development of measures to guide efforts.

Designing a Low-Cost, Single-Supply ECG System for Suppression of Movement Artifact from Contaminated Magnetocardiogram.

Measurement of the late potentials and His-bundle activity is crucial for many clinical studies using the noncontact and noninvasive magnetocardiography (MCG) technique; these weak signals are extracted by averaging many cardiac cycles aligned using the R-peak of the cardiac cycle identified using an electrocardiography (ECG) lead. ECG is measured simultaneously with MCG using a conventional dual-supply ECG amplifier, which requires either two separate batteries or a single battery with a switching voltage inverter circuit for its proper operation. The ECG circuitry based on two separate batteries requires a relatively large voltage supply (-18 to +18 V). The single-supply (low voltage: 0-9 V) ECG circuitry may be implemented using a switching voltage inverter; however, this mode of operation introduces switching noise in the system. The objective of the present work is to overcome these problems by carefully designing a low-voltage, single-supply ECG system, which can be used simultaneously with the MCG setup without introducing a significant level of additional noise in the MCG measurement system.

The UK EndoVascular Aneurysm Repair (EVAR) randomised controlled trials: long-term follow-up and cost-effectiveness analysis.

BACKGROUND: Short-term survival benefits of endovascular aneurysm repair (EVAR) compared with open repair (OR) of intact abdominal aortic aneurysms have been shown in randomised trials, but this early survival benefit is soon lost. Survival benefit of EVAR was unclear at follow-up to 10 years. OBJECTIVE: To assess the long-term efficacy of EVAR against OR in patients deemed fit and suitable for both procedures (EVAR trial 1; EVAR-1); and against no intervention in patients unfit for OR (EVAR trial 2; EVAR-2). To appraise the long-term significance of type II endoleak and define criteria for intervention. DESIGN: Two national, multicentre randomised controlled trials: EVAR-1 and EVAR-2. SETTING: Patients were recruited from 37 hospitals in the UK between 1 September 1999 and 31 August 2004. PARTICIPANTS: Men and women aged ≥ 60 years with an aneurysm of ≥ 5.5 cm (as identified by computed tomography scanning), anatomically suitable and fit for OR were randomly assigned 1 : 1 to either EVAR (n = 626) or OR (n = 626) in EVAR-1 using computer-generated sequences at the trial hub. Patients considered unfit were randomly assigned to EVAR (n = 197) or no intervention (n = 207) in EVAR-2. There was no blinding. INTERVENTIONS: EVAR, OR or no intervention. MAIN OUTCOME MEASURES: The primary end points were total and aneurysm-related mortality until mid-2015 for both trials. Secondary outcomes for EVAR-1 were reinterventions, costs and cost-effectiveness. RESULTS: In EVAR-1, over a mean of 12.7 years (standard deviation 1.5 years; maximum 15.8 years), we recorded 9.3 deaths per 100 person-years in the EVAR group and 8.9 deaths per 100 person-years in the OR group [adjusted hazard ratio (HR) 1.11, 95% confidence interval (CI) 0.97 to 1.27; p = 0.14]. At 0-6 months after randomisation, patients in the EVAR group had a lower mortality (adjusted HR 0.61, 95% CI 0.37 to 1.02 for total mortality; HR 0.47, 95% CI 0.23 to 0.93 for aneurysm-related mortality; p = 0.031), but beyond 8 years of follow-up patients in the OR group had a significantly lower mortality (adjusted HR 1.25, 95% CI 1.00 to 1.56, p = 0.048 for total mortality; HR 5.82, 95% CI 1.64 to 20.65, p = 0.0064 for aneurysm-related mortality). The increased aneurysm-related mortality in the EVAR group after 8 years was mainly attributable to secondary aneurysm sac rupture, with increased cancer mortality also observed in the EVAR group. Overall, aneurysm reintervention rates were higher in the EVAR group than in the OR group, 4.1 and 1.7 per 100 person-years, respectively (p < 0.001), with reinterventions occurring throughout follow-up. The mean difference in costs over 14 years was £3798 (95% CI £2338 to £5258). Economic modelling based on the outcomes of the EVAR-1 trial showed that the cost per quality-adjusted life-year gained over the patient's lifetime exceeds conventional thresholds used in the UK. In EVAR-2, patients died at the same rate in both groups, but there was suggestion of lower aneurysm mortality in those who actually underwent EVAR. Type II endoleak itself is not associated with a higher rate of mortality. LIMITATIONS: Devices used were implanted between 1999 and 2004. Newer devices might have better results. Later follow-up imaging declined, particularly for OR patients. Methodology to capture reinterventions changed mainly to record linkage through the Hospital Episode Statistics administrative data set from 2009. CONCLUSIONS: EVAR has an early survival benefit but an inferior late survival benefit compared with OR, which needs to be addressed by lifelong surveillance of EVAR and reintervention if necessary. EVAR does not prolong life in patients unfit for OR. Type II endoleak alone is relatively benign. FUTURE WORK: To find easier ways to monitor sac expansion to trigger timely reintervention. TRIAL REGISTRATION: Current Controlled Trials ISRCTN55703451. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and the results will be published in full in Health Technology Assessment; Vol. 22, No. 5. See the NIHR Journals Library website for further project information.

Identification of appropriate QTc formula in beagle dogs for nonclinical safety assessment.

A number of drugs belonging to different therapeutic classes cause increase in QT interval duration, and this change has been associated with ventricular arrhythmias. Investigation of changes in QT intervals in toxicity studies in dogs is therefore of potential value. Estimation of a direct effect of drugs on the duration of the QT interval can be confused by drug-induced increases in heart rate. The objective of this evaluation was to identify an appropriate correction formula by comparing different formulae that could appropriately correct changes in QT interval in conscious beagle dogs in toxicology studies. Most commonly used QTc (QT correction) formulae are derived from human observations, like Bazett's formula and thus are not applicable for other species like dogs, where the normal values of heart rate is higher compared to humans. Using our historical data, we have established and compared different correction formulas and found that Van de Water's formula is the most appropriate for dog under conditions stated. However, there is no universally accepted formula for QTc calculation in dogs, and hence each organization should have its own formula, based on the analysis of data obtained from the strain used in its own experimental conditions.

Bacterial tag encoded FLX titanium amplicon pyrosequencing (bTEFAP) based assessment of prokaryotic diversity in metagenome of Lonar soda lake, India.

Bacterial diversity and archaeal diversity in metagenome of the Lonar soda lake sediment were assessed by bacterial tag-encoded FLX amplicon pyrosequencing (bTEFAP). Metagenome comprised 5093 sequences with 2,531,282 bp and 53 ± 2% G + C content. Metagenome sequence data are available at NCBI under the Bioproject database with accession no. PRJNA218849. Metagenome sequence represented the presence of 83.1% bacterial and 10.5% archaeal origin. A total of 14 different bacteria demonstrating 57 species were recorded with dominating species like Coxiella burnetii (17%), Fibrobacter intestinalis (12%) and Candidatus Cloacamonas acidaminovorans (11%). Occurrence of two archaeal phyla representing 24 species, among them Methanosaeta harundinacea (35%), Methanoculleus chikugoensis (12%) and Methanolinea tarda (11%) were dominating species. Significant presence of 11% sequences as an unclassified indicated the possibilities for unknown novel prokaryotes from the metagenome.

Shotgun metagenomic sequencing based microbial diversity assessment of Lasundra hot spring, India.

This is the first report on the metagenomic approach for unveiling the microbial diversity of Lasundra hot spring, Gujarat State, India. High-throughput sequencing of community DNA was performed on an Ion Torrent PGM platform. Metagenome consisted of 606,867 sequences represent 98,567,305 bps size with an average length of 162 bps and 46% G + C content. Metagenome sequence information is available at EBI under EBI Metagenomic database with accession no. ERP009313. MG-RAST assisted community analysis revealed that 99.21% sequences were bacterial origin, 0.43% was fit to eukaryotes and 0.11% belongs to archaea. A total of 29 bacterial, 20 eukaryotic and 4 archaeal phyla were detected. Abundant genera were Bacillus (86.7%), Geobacillus (2.4%), Paenibacillus (1.0%), Clostridium (0.7%) and Listeria (0.5%), that represent 91.52% in metagenome. In functional analysis, Cluster of Orthologous Group (COG) based annotation revealed that 45.4% was metabolism connected and 19.6% falls in poorly characterized group. Subsystem based annotation approach suggests that the 14.0% was carbohydrates, 7.0% was protein metabolism and 3.0% genes for various stress responses together with the versatile presence of commercially useful traits.

Surgical treatment of type 2 diabetes: the surgeon perspective.

Type 2 diabetes mellitus (T2DM) is a major health priority globally, having achieved pandemic status in the twenty-first century. Several gastrointestinal procedures that were primarily designed to treat morbid obesity result in dramatic remission of diabetes. Studies in experimental rodent models and humans have shown that the glycemic benefits of surgery are at least in part weight-independent and extend to non-morbidly obese subjects with T2DM. Bariatric procedures differ in their ability to ameliorate type 2 diabetes, with intestinal bypass procedures being more effective than purely restrictive procedures. Several studies have demonstrated that the benefits of bariatric surgery extend beyond amelioration of hyperglycemia and include improvement in other cardiovascular risk factors such as dyslipidemia and hypertension. The safety and cost-effectiveness of bariatric surgery are also well established by several studies. In this paper, the authors present the surgeon perspective on the management of type 2 diabetes focusing on the efficacy, safety and cost-effectiveness of metabolic surgery. The available evidence warrants the inclusion of metabolic surgery in the treatment algorithm of type 2 diabetes.

Clinical evaluation of a phalangeal bone mineral density assessment system.

Because osteoporosis is common and usually managed in primary care, there is a requirement for cheap and convenient methods of measuring bone mineral density (BMD). AccuDEXA (Lone Oak Medical Technologies, Doylestown, PA) is a tabletop dual-energy X-ray absorptiometry (DXA) device that performs BMD measurements of the hand in the middle phalanges of the third finger. The aims of this study were to (1) evaluate the use of AccuDEXA in UK women; (2) investigate the concordance between AccuDEXA T-scores and DXA T-scores for central (spine and hip) sites; (3) investigate the comparative response of AccuDEXA measurements to clinical risk factors for osteoporosis. Measurements of phalangeal and central BMD were performed in 620 women referred by their family doctors for bone densitometry (group 1) and 159 healthy female volunteers (group 2). For 65 women in group 2, aged 39 yr or younger, the mean Z-scores for AccuDEXA and the central sites calculated from US reference ranges were consistent with the expected value of 0, whereas for the 62 group 2 women, aged 50 yr or older, the mean Z-scores for AccuDEXA and the central sites were in the range 0.4-0.7 and were statistically significantly different from 0. In both group 1 and group 2, the AccuDEXA T-scores in older and younger women were systematically higher than those in the central sites by up to 1 unit. Of the 157 women aged 50 yr or older, with osteoporosis, based on their central DXA results, only 34 (22%) had an AccuDEXA T-score less than or equal to -2.5, whereas 76 (48%) had osteopenia and 47 (30%) were normal based on their AccuDEXA T-scores. When assessed by the effect of clinical risk factors on Z-scores, both AccuDEXA and central BMD were affected to a similar extent. We conclude that the conventional World Health Organisation T-score criteria for the diagnosis of osteoporosis should not be applied to AccuDEXA measurements in UK women. Clinical risk factors for low BMD were found to affect AccuDEXA measurements to a similar extent as central BMD measurements. AccuDEXA measurements could, therefore, provide an alternative method for identifying individuals with low bone mass, provided care is taken in interpreting T-scores, perhaps, through the use of device-specific thresholds.

Economic appraisal of supercritical fluid extraction of refined cashew nut shell liquid.

This manuscript summarises the techno-economic feasibility of refined cashew nut shell liquid (CNSL). A simple mass transfer based mathematical model for the yield prediction is presented. The process parameters and extraction time for maximum profit and purity of the product were optimized. The optimum extraction time for maximum profit and purity was found to be 0.9h at 300 bar and 323 K. The influence of the different costs, such as fixed cost, raw material cost, labor cost, utility cost, etc. on profit and cost of production of the extract is also presented.