Machine learning models of 6-lead ECGs for the interpretation of left ventricular hypertrophy (LVH).

BACKGROUND: Left Ventricular Hypertrophy (LVH) is closely linked to the cardiovascular disease prognosis, and thus, timely diagnosis improves outcomes. Diagnosis is challenging due to dependency on doctor's visits and a 12­lead ECG. In addition, the interpretation of LVH from ECGs is challenging due to variability of ECG measurements, body habitus, electrode positioning, several LVH ECG criteria and EP mechanisms. The aims of this study are to evaluate different big data-driven machine learning models for ECG LVH interpretation based on limb leads only, and to compare the performance of an ECG parameter-based statistical model with a deep learning-based model. METHODS AND DATA: The first two models are binary class Random Forest (RF) models, an ensemble learning method which constructs many decision trees at training time and predicts the class chosen by the greatest number of trees at inference time. One random forest is trained using the following five features: lead aVL R-wave amplitude, lead I, II, aVL ST segment amplitude, and QRS duration. The second RF model uses 54 features across all limb leads, including the five features used by the smaller model. The second type of model is a multi-class deep neural network (DNN) which takes median beats of 6 limb leads arranged in Cabrera sequence as input. The signal preprocessing included forming median beats, filtering with a 40-Hz lowpass filter, and down-sampling to 125 Hz. The DNN models consist of 1 lead-formation convolutional layer, 5 downsampling convolutional resnet blocks with skip connections, and 3 fully connected layers. The training dataset consisted of 1 million 10-s 12­lead ECGs, and an independent test dataset consisted of 250,000 10-s ECGs from the Mayo Clinic. RESULTS: The five-parameter RF model has the prediction performance of Area Under the Receiver-Operator Curve (AUC) 0.78, and the larger RF model had AUC of 0.83. The DNN model for ECG LVH detection achieves AUC 0.92 using only the limb leads, compared to an AUC of 0.98 for the full 12­lead DNN. CONCLUSION: The study shows that machine learning models trained only on limb leads achieve promising results with potential to add clinical value to early detection mechanisms. We also observe that the RF model splits parameters by thresholds known to be characteristic of LVH, and that the DNN model can automatically detect morphology differences from 6 limb lead ECGs. This will be meaningful for expanding the capabilities of potential electrical LVH detection in mobile 6­lead ECG devices.

Genotypic characterization of group A rotavirus in children < 5 years of age at tertiary care hospital in North India.

PURPOSE: This study was undertaken to find out the positivity of rotavirus associated diarrhoea in children <5 years of age in Meerut district and to determine the genomic diversity of the circulating rotavirus strains in this geographical area. METHODS: A cross-sectional study was conducted in a tertiary care hospital for a period of one year. A total of 240 stool samples were collected from children suffering from acute diarrhoea and subjected for rotavirus antigen detection by enzyme immunoassay (EIA). The EIA-positive samples were further genotyped to determine the G and P types using semi nested multiplex reverse transcriptase-polymerase chain reaction (RT-PCR). Demographic and clinical parameters were recorded in a pre-designed proforma. RESULTS: The rotavirus antigen positivity rate was 14.58% in Meerut district. There was male predominance and highest positivity rate was seen in children 13-24 months of age, in winter months and majority of cases belonged to moderate degree of severity. A total of 64% children in the study area were vaccinated and positivity was low in the vaccine group. G9P[4] was the predominant genotype followed by G3P[8]. Uncommon strains G12P[6] and G12P[8] were also reported as circulating genotypes in this study. CONCLUSIONS: The positivity rate of rotavirus associated diarrhoea has reduced in Meerut district post vaccination. G9P[4] was the most common circulating RV genotype in Meerut. Our study highlights the importance of including the emerging rotavirus strains in future multivalent RV vaccines to make the vaccines regionally more specific.

Longitudinally extensive transverse myelitis following dengue virus infection: A rare entity.

Association of dengue fever with longitudinally extensive transverse myelitis in pediatric age group is a rare entity. We describe a case of 15 year old adolescent male who presented with dengue fever and in whom symptoms of transverse myelitis developed 4 weeks after fever (post-infectious stage). Magnetic resonance imaging confirmed the diagnosis of longitudinally extensive transverse myelitis involving dorso-lumbar cord. Patient recovered almost completely with minimal residual neurological deficit after a six weeks course of corticosteroids and supportive management including physiotherapy.

L'association de la dengue avec une myélite transversale longitudinale étendue dans un groupe d'âge pédiatrique est une entité rare. Nous décrivons un cas d'un adolescent de 15 ans qui présentaient une dengue et chez lesquels des symptômes de myélite transversale se sont développés 4 semaines après la fièvre (stade post-infectieux). L'imagerie par résonance magnétique a confirmé le diagnostic de myélite transversale longitudinale étendue impliquant le cordon dorso-lombaire. Le patient s'est rétabli presque complètement avec un déficit neurologique résiduel minimal après un traitement de corticostéroïdes de six semaines et une prise en charge, y compris la physiothérapie. Mots-clés: La fièvre de la dengue, la myélite transversale longitudinalement étendue, le virus neurotroptique.

Trends in authorship based on gender and nationality in published neuroscience literature.

OBJECTIVE: To evaluate the disparity in authorship based on gender and nationality of institutional affiliation among journals from developed and developing countries. MATERIALS AND METHODS: Original articles from two neuroscience journals, with a 5 year impact factor >15 (Neuron and Nature Neuroscience) and from two neurology journals from a developing country (Neurology India and Annals of Indian Academy of Neurology) were categorized by gender and institutional affiliation of first and senior authors. Articles were further divided by the type of research (basic/translational/clinical), study/target population (adult/pediatrics/both) and field of neurology. Data was collected for the years 2002 and 2012. RESULTS: There are large disparities in authorship by women and from developing countries in high impact factor neuroscience journals. However, there was a non-statistical rise in female first and senior authorship over a 10 year period. Additionally there was a significant increase in first authorship from institutions based in developing countries in the two neuroscience journals examined (P < 0.05). In the two neurology journals based in India there was a significant increase in the number of articles published by international investigators between 2002 and 2012 (P < 0.05). CONCLUSIONS: Over the last decade, there has been a non-statistical increase in proportion of female first and senior authors, and a significant increase in authors from developing countries in high impact factor neuroscience journals. However they continue to constitute a minority. The disparity in authorship based on gender also exists in neurology journals based in a developing country (India).

First-principles electronic structure study of rhizoferrin and its Fe(III) complexes.

We have determined the structure and coordination chemistry of rhizoferrin (Rf), which is a particular type of siderophore, and its Fe(III) complexes using density functional theory calculations. Our results show that the Fe(III) ion binds in an octahedral coordination, with a low-spin (S = 1/2) charge-neutral chiral complex having the largest binding energy of the investigated complexes. We have also calculated nuclear magnetic resonance parameters, such as chemical shifts for (1)H and (13)C, and indirect nuclear spin-spin couplings for (1)H-(1)H and (13)C-(1)H in free Rf and in a low-spin neutral Rf metal complex, as well as nuclear quadrupole interaction parameters, such as asymmetry parameter and nuclear quadrupole coupling constants for (14)N. Our calculated values for the chemical shifts for free Rf are in excellent agreement with experimental data while the calculated NMR parameters for Fe(III) complexes are predictions for future experimental work.

Identification of pharmacophore in bioactive metal complexes: Synthesis, spectroscopic characterization and application.

Bacteria are amongst the most adaptable organisms on the Earth. The year 2010 was always remarkable for the article published in Lancet Infection Disease by Kumarasamy et al. and the enzyme NDM-1 which makes bacteria resist designed to kill them. Four rhodium(III) chloride complexes with Gatifloxacin have been prepared and characterized by elemental analyses, molar conductance measurements, FTIR, FAB-MS, TGA, (1)H NMR and electronic spectral studies. The general formula for complexes are [X](+)fac-[RhCl(3)(L)(GT)](-); where L = H(2)O, Dimethylsulfoxide (DMSO), Tetramethylenesulfoxide (TMSO); GT = Gatifloxacin and X = Na or [H(DMSO)(2)]. All complexes are found to possess prominent antibacterial activity against pathogenic Escherichia coli and Mycobacterium tuberculosis in comparison to Gatifloxacin.

Identification of species-specific RAPD markers in genus Cenchrus.

Cenchrus is an important component of major grass cover of world. Similar to the other major tropical grasses most of the species in genus Cenchrus are also apomictic in nature hence correct and precise identification of accessions and species are problematic and dubious. In the present study 187 decamer oligonucleotide primers were tested for PCR-based DNA amplification of six prominent species of genus Cenchrus. Of these, 32 potential repetitive and polymorphic primers were tested for identification of species-specific markers for C. ciliaris, C. setigerus, C. pennisetiformis, C. prieurri, C. biflorus and C. myosuroides. These primers yielded 51 unique RAPD markers either specific to a species (37) or shared by two or more species (14). Maximum markers were shared between C. ciliaris and C. setigerus confirming theirmore closeness to each other Primers like OPF09, OPF11, OPR15, OPAJ11, OPQ10 and OPAK20 generated strong intense bands can be used on priority in identifying the species from their natural habitat for the development of species-specific core germplasm. Due to apomictic nature this is the prime method of developing cultivars, as morphological characters are largely unable to distinguish them. The level of variation observed clearly suggest RAPD as an appropriate marker for genetic studies and in identifying the lines with species-specific markers for Cenchrus germplasm management activity and also maintaining identity and purity for proprietary reasons.

Effect of ploidy levels on the activities of delta(1)-pyrroline-5-carboxylate synthetase, superoxide dismutase and peroxidase in Cenchrus species grown under water stress.

The effects of ploidy levels on the activities of delta(1)-pyrroline-5-carboxylate synthetase (P5CS; EC not assigned), superoxide dismutase (SOD; EC 1.15.1.1) and guaiacol peroxidase (POX; EC 1.11.1.7), as well as malondialdehyde (MDA) and proline contents were studied in two months old plants of Cenchrus species. The Cenchrus species represent three ploidy levels: diploid, tetraploid, hexaploid and two life spans: annual and perennial. Plants were subjected to water stress for 2, 4, 6 and 8 d by withholding water under glasshouse conditions. Although the levels of proline increased with the magnitude of water stress, the P5CS activity did not show a corresponding increase in all species. Peroxidase and superoxide dismutase activities showed an increase or steady state in the early phase of drought and then declined with the further increase in the magnitude of water stress, indicating differing behaviors of species towards drought tolerance. Under drought, diploid Cenchrus species had a higher POX activity, MDA accumulation and lower proline content than tetraploid species. Lower POX and higher P5CS activities and proline contents, however, were observed in hexaploid and tetraploid species. Taken together, our findings suggest that diploid species have a less efficient antioxidant system to scavenge reactive oxygen species than tetra and hexaploid Cenchrus. This may result in a corresponding variability in growth and persistence under natural grasslands. The study also paves the way for investigations on the molecular events associated with drought in Cenchrus species differing in ploidy and life span.

Effect of water stress on carbon isotope discrimination and its relationship with transpiration efficiency and specific leaf area in Cenchrus species.

Carbon isotope discrimination (CID) has been proposed in estimating transpiration efficiency (TE) in plants indirectly To identify variations for TE and specific leaf area (SLA) and their association with CID, a glasshouse experiment was conducted using six prominent species of Cenchrus. A significant increase in TE (3.50 to 3.87 g kg(-1)) and decrease in SLA (219.50 to 207.99 cm2 g(-1)) and CID (13.72 to 13.23% per hundred) was observed from well watered to stress condition. Results indicated a direct relationship of SLA with CID (r = 0.511* and 0.544*) and inverse relationship between TE and CID (r = -0.229 and -0.270) However the relationship of TE with CID was insignificant. A positive and significant relationship was visualized between TE and dry matter production in both control (r = 0.917**) and stress (0.718**) treatments. Relationships of total dry matter with SLA and CID were monitored insignificant and negative in control and positive in stress treatment indicated difference in dry matter production under two treatments. It seems that, in Cenchrus species, CID was influenced more by the photosynthetic capacity than by stomatal conductance, as indicated by its positive relationship with SLAin both control (r = 0.511) and stress (r = 0.544) conditions and negative relationship with root dry matter production under control (r = -0.921**) and stress (r = -0.919***) condition. Results showed good correspondence between CID and SLA, indicating that lines having high TE and biomass production can be exploited for their genetic improvement for drought.