Management and Outcomes of COVID - 19 Associated Cerebral Venous Sinus Thrombosis.

BACKGROUND: Systemic hyper-coagulabilty leading to micro and macro thrombosis is a known complication of Coronavirus disease - 2019(COVID -19). The postulated mechanism appears to be the viral activation of endothelium, triggering the coagulation pathways. Thrombosis of the cerebral veins and sinuses (CVT), a potentially serious condition, has been increasingly reported with COVID - 19 infection. In this clinical study we attempt to describe the clinical profile, investigations and outcomes of patients with COVID- 19 associated CVT. METHODS: This is a single center prospective observational study from South India. The study included patients (aged >18 years) with concomitant COVID infection and CVT. The clinical, laboratory, imaging characteristics, management and outcomes were described and compared with COVID negative CVT patients. RESULTS: Out of 97 cases of CVT treated at our center during the first and second waves of the COVID pandemic 11/97 (11%) were COVID related CVT. Among these 11 patients, 9 (81%) had presented with only CVT related symptoms and signs and were tested positive for COVID - 19 infection during the pre-hospitalization screening. Respiratory symptoms were absent in 90% of the patients. Headache (100%) and seizures (90%) were the common presenting symptoms. The median time to diagnosis was 6 hours, from presentation to the emergency department. Transverse sinus was involved 10/11 (90%) and majority of them (9/11) had Haemorrhagic Venous Infarction (HVI). Acute inflammatory markers were elevated in comparison with non COVID CVT patients, with the mean serum D-dimer being 2462.75 ng/ml and the C-reactive protein was 64.5 mg/dl. Three patients (30%) underwent decompressive hemicraniectomy (DHC) because of large hemispheric HVI. All patients survived in the COVID CVT group while the mortality in the non COVID group was 4%. At 6 months follow up excellent outcome (modified Rankin Scale (mRS) score of 0-2) was noted equally in both groups. CONCLUSIONS: Symptoms and signs of CVT may be the only presentation of COVID-19 infection. Prompt recognition and aggressive medical management including DHC offers excellent outcomes.

Cerebral Venous Thrombosis, Seasonal Trends, and Climatic Influence: A Region-SpecificStudy.

BACKGROUND AND PURPOSE: Studies looking at seasonal variation on cerebral venous thrombosis (CVT) are few with conflicting conclusions. In this region-specific study, we looked for climatic influence and seasonal trends on the incidence of CVT. METHODS: Imaging proven adult CVT cases treated over a period of 18 years from a specific geographical location with similar seasons and climatic conditions were studied. Metrological parameters prepared using 30 years of data was used. Quantum geographical information system (QGIS software) and SPSS v 22 were used for patient plotting and analysis. RESULTS: Total of 970 cases were studied. The incidence was significantly higher in summer 411 (42.3%) compared with autumn 317 (32.7%) and winter 242 (25.05); P = 0.038. This trend was consistent across all the 18 years in time series analysis. Mean age was 33.5 years (range 18-88 years). A significant majority 673 (69.4%) were below 40 years of age; P = 0.012. Females constituted 394 (40.6%) of cases. Postpartum CVT cases constituted 237 (30%). Interaction analysis showed younger age (<40 years) were more vulnerable for CVT in summer; P = 0.009. There was no seasonal influence on postpartum CVT. Apart for a weak positive correlation between rain fall (r = 0.18, P < 0.01); humidity and cloud cover was not influencing the incidence. CONCLUSIONS: Higher ambient temperatures were consistently associated with higher incidence of CVT. This is the largest region-specific study on CVT in the world. These results may be applicable to other regions with similar climatic conditions.

Communication: Potentials of mean force study of ionic liquid ion pair aggregation in polar covalent molecule solvents.

Molecular dynamics (MD) simulations were conducted for 1-ethyl-3-methylimidazolium methylsulfate [EMIM][MeSO4] dissolved in six polar covalent molecules [acetic acid, acetone, chloroform, dimethyl sulfoxide (DMSO), isopropyl alcohol, and methanol] to understand the free energies of ionic liquid (IL) ion pairing/aggregation in the limit of infinite dilution. Free energy landscapes or potentials of mean force (PMF) were computed using umbrella sampling and the weighted histogram analysis method. The PMF studies showed the strongest IL ion pairing in chloroform, and the strength of IL ion pairing decreases in the order of chloroform, acetone, propanol, acetic acid, DMSO, and methanol. In the limit of infinite dilution, the free energy curves for IL ion aggregation in co-solvents were characterized by two distinct minima [global (∼3.6 Å) and local (∼5.7 Å)], while free energy values at these minima differed significantly for IL in each co-solvent. The PMF studies were extended for determining the free energy of IL ion aggregation as a function of concentration of methanol. Studies showed that as the concentration of methanol increased, the free energy of ion aggregation decreased, suggesting greater ion pair stability, in agreement with previously reported MD clustering and radial distribution function data.

Simultaneous hydrolysis and fermentation of unprocessed food waste into ethanol using thermophilic anaerobic bacteria.

The one-pot CRUDE (Conversion of Raw and Untreated Disposal into Ethanol) process was developed for simultaneous hydrolysis and fermentation of unprocessed food waste into ethanol using thermophilic (growing at 65°C) anaerobic bacteria. Unlike existing waste to energy technologies, the CRUDE process obviates the need for any pre-treatment or enzyme addition. A High-Temperature-High-Pressure (HTHP) distillation technique was also applied that facilitated efficient use of fermentation medium, inoculum recycling, and in-situ ethanol collection. For material balancing of the process, each characterized component was represented in terms of C-mol. Recovery of 94% carbon at the end confirmed the operational efficiency of CRUDE process. The overall energy retaining efficiency calculated from sugars to ethanol was 1262.7kJdryweightkg-1 of volatile solids using HTHP. These results suggest that the CRUDE process can be a starting point for the development of a commercial ethanol production process.

Molecular simulation of CO chemisorption on Co(0001) in presence of supercritical fluid solvent: A potential of mean force study.

For several decades, heterogeneous catalytic processes have been improved through utilizing supercritical fluids (SCFs) as solvents. While numerous experimental studies have been established across a range of chemistries, such as oxidation, pyrolysis, amination, and Fischer-Tropsch synthesis, still there is little fundamental, molecular-level information regarding the role of the SCF on elementary heterogeneous catalytic steps. In this study, the influence of hexane solvent on the adsorption of carbon monoxide on Co(0001), as the first step in the reaction mechanism of many processes involving syngas conversion, is probed. Simulations are performed at various bulk hexane densities, ranging from ideal gas conditions (no SCF hexane) to various near- and super-critical hexane densities. For this purpose, both density functional theory and molecular dynamics simulations are employed to determine the adsorption energy and free energy change during CO chemisorption. Potential of mean force calculations, utilizing umbrella sampling and the weighted histogram analysis method, provide the first commentary on SCF solvent effects on the energetic aspects of the chemisorption process. Simulation results indicate an enhanced stability of CO adsorption on the catalyst surface in the presence of supercritical hexane within the reduced pressure range of 1.0-1.5 at a constant temperature of 523 K. Furthermore, it is shown that the maximum stability of CO in the adsorbed state as a function of supercritical hexane density at 523 K nearly coincides with the maximum isothermal compressibility of bulk hexane at this temperature.

Fourth and fifth virial coefficients of polarizable water.

We report values of the viral coefficients B4 and B5 for the Gaussian charge polarizable model (GCPM) of water using the overlap-sampling implementation of Mayer sampling molecular simulation. These results supplement values for the lower-order coefficients B2 and B3 reported previously, and in the present work, we provide more precise values of these coefficients as well. The precision of all viral coefficients is such that the standard error in the calculated pressure is significantly less than 1% for most temperatures, with the exception of temperatures near the critical, where the error approaches 100% at the critical density, and supercritical, where the uncertainty in B5 introduces an error of about 5% in the pressure at the critical density. We examine these coefficients in the context of the equation of state and molecular clustering. Comparisons are made to established molecular simulation data, quantum chemical calculations, and experimental data for real water. Over both sub- and supercritical temperatures, the viral series to B5 is accurate for densities only up to about half the critical density. In this regime, deviation is observed from experimental data for real water, and it is suggested that further development of the model might do well to further improve the relatively good agreement it has with the experimental second viral coefficient of water. The viral coefficients are used to characterize molecular clusters (dimers through pentamers) in GCPM water under supercritical and saturated vapor conditions between 210 and 673 K.

Higher-order virial coefficients of water models.

We use the Mayer sampling method, with both direct and overlap sampling, to calculate and compare classical virial coefficients up to B6 for various water models (SPC, SPC/E, MSPC/E, TIP3P, and TIP4P). The precision of the computed values ranges from 0.1% for B2 to an average of 25% for B6. When expressed in a form scaled by the critical properties, the values of the coefficients for SPC water are observed to greatly exceed the magnitude of corresponding coefficients for the simple Lennard-Jones model. We examine the coefficients in the context of the equation of state and the Joule-Thomson coefficient. Comparisons of these properties are made both to established molecular simulation data for each respective model and to real water. For all models, the virial series up to B5 describes the equation of state along the saturated vapor line better than the series that includes B6. At supercritical temperatures, however, the sixth-order series often describes pressure-volume-temperature behavior better than the fifth-order series. For example, the sixth-order virial equation of state for SPC/E water predicts the 673 K isotherm within 8% of published molecular simulation values up to a density of 9 mol/L (roughly half the critical density of SPC/E water).

Measurement of itch using actigraphy in pediatric and adult populations.

We have studied nocturnal movements using wrist-worn accelerometers in 33 adults with a range of pruritic dermatoses, 30 adult control subjects, 25 children with atopic dermatitis, and 17 pediatric control subjects. In all, 26 adults and 20 children were studied on more than one occasion, up to a maximum of 6 occasions. Participants were examined and a range of subjective measures about the extent of skin disease, itch, and quality of sleep were recorded. We show clear differences between patients and control subjects for both age groups studied, with activity medians approximately twice as high in the patients as in the control subjects ( P < .001). Studies on the same person show a considerable night-to-night variation that is unlikely to relate to measurement error, but instead, we believe, reflect genuine differences in nocturnal activity (and perhaps disease severity). Movement through the night did not seem to follow any obvious pattern. The relation between subjective measures, Severity sCORing of Atopic Dermatitis (SCORAD) index scores, and objective recorded activity was imperfect, with much unaccounted for variation. In particular, in adults, but not in children, we found a negative correlation (-0.44, P < .02) between objective movement activity and self-reported quality of sleep. Our results support the use of objective measures of scratch in the assessment of disease activity, and suggest that the relation between subjective and objective measures of disease severity may not be straightforward.

The development of an objective method for measuring scratch in children with atopic dermatitis suitable for clinical use.

Itch is a major symptom of skin disease and remains poorly studied. We have used limb-worn digital accelerometers, and infrared video of patients as a gold standard, on children with atopic dermatitis and control subjects in their own homes at night. Video analysis shows that nocturnal scratching and restlessness are more complex than we first thought, with many movements that potentially damage the skin not conforming to stereotypical scratch movements. Children with atopic dermatitis spent a mean of 46 minutes less time motionless or sleeping at night than control subjects (468 +/- 3 [SEM] vs 422 +/- 37 [SEM], P<.001). Children with atopic dermatitis showed 2 to 3 times as much scratching or restlessness activity as control subjects, with little overlap between groups (P<.01). Scratching and restlessness were highly correlated with each other (0.94, P<.01). Accelerometer scores were highly correlated with video results (rho>0.02, P<.01, for scratching, restlessness, and sleeping time). Individual limb scores were highly correlated with each other (rho approximately 0.87-0.98), suggesting that little information would be lost if only 1 limb was measured. There was little relation between parental assessment of scratch and objective measured scratch. Accelerometers provide a useful and practical way of assessing scratching at night in the patient's own home and could be used as an objective measure of disease activity both in clinical trials and in everyday clinical practice.