ARIMA modelling & forecasting of COVID-19 in top five affected countries.

BACKGROUND AND AIMS: In a little over six months, the Corona virus epidemic has affected over ten million and killed over half a million people worldwide as on June 30, 2020. With no vaccine in sight, the spread of the virus is likely to continue unabated. This article aims to analyze the time series data for top five countries affected by the COVID-19 for forecasting the spread of the epidemic. MATERIAL AND METHODS: Daily time series data from 15th February to June 30, 2020 of total infected cases from the top five countries namely US, Brazil, India, Russia and Spain were collected from the online database. ARIMA model specifications were estimated using Hannan and Rissanen algorithm. Out of sample forecast for the next 77 days was computed using the ARIMA models. RESULTS: Forecast for the first 18 days of July was compared with the actual data and the forecast accuracy was using MAD and MAPE were found within acceptable agreement. The graphic plots of forecast data suggest that While Russia and Spain have reached the inflexion point in the spread of epidemic, the US, Brazil and India are still experiencing an exponential curve. CONCLUSION: Our analysis shows that India and Brazil will hit 1.38 million and 2.47 million mark while the US will reach the 4.29 million mark by 31st July. With no effective cure available at the moment, this forecast will help the governments to be better prepared to combat the epidemic by ramping up their healthcare facilities.

Post-periodontal surgery propounds early repair salivary biomarkers by 1H NMR based metabolomics.

INTRODUCTION: Oral microflora is a well-orchestrated and acts as a sequential defense mechanism for any infection related to oral disease. Chronic periodontitis is a disease of a microbial challenge to symbiosis and homeostasis. Periodontal surgery is the most promising cure with repair process during periodontal regeneration. It has an encouraging outcome in terms of early recovery biomarkers. OBJECTIVE: Saliva of periodontal surgery subjects with the chronic periodontitis have been evaluated by 1H NMR spectroscopy in search of possible early metabolic differences that could be obtained in order to see the eradication of disease which favours the symbiotic condition. METHOD: The study employed 1H NMR spectroscopy on 176 human saliva samples in search of distinctive differences and their spectral data were further subjected to multivariate and quantitative analysis. RESULT: The 1H NMR study of periodontal surgery samples shows clear demarcation and profound metabolic differences when compared with the diseased condition. Several metabolites such as lactate, ethanol, succinate, and glutamate were found to be of higher significance in periodontal surgery in contrast to chronic periodontitis subjects. The PLS-DA model of the studied group resulted in R2 of 0.83 and Q2 of 0.70. CONCLUSION: Significant metabolites could be considered as early repair markers for chronic periodontitis disease as they are being restored to achieve symbiosis. The study, therefore, concluded the early recovery process of the diseased subjects with the restoration of possible metabolomic profile similar to the healthy controls.

Hexafluoroisopropanol-induced helix-sheet transition of stem bromelain: correlation to function.

Stem bromelain is a proteolytic phytoprotein with a variety of therapeutic effects. Understanding its structural properties could provide insight into the mechanisms underlying its clinical utility. Stem bromelain was evaluated for its conformational and folding properties at the pH conditions it encounters when administered orally. It exists as a partially folded intermediate at pH 2.0. The conformational changes to this intermediate state were evaluated using fluorinated alcohols known to induce changes similar to those seen in vivo. Studies using circular dichroism, fluorescence emission spectroscopy, binding of the hydrophobic dye 1-anilino-8-naphthalene sulfonic acid and mass spectrometry indicate that treatment with 10-30% hexafluoroisopropanol induces the partially folded intermediate to adopt much of the native protein's secondary structure, but only a rudimentary tertiary structure, characteristic of the molten globule state. Addition of slightly higher concentrations of hexafluoroisopropanol caused transformation from an alpha-helix to a beta-sheet and induced formation of a compact nonnative structure. This nonnative form was more inhibitory of cell survival than either the native or the partially folded intermediate forms, as measured by enhanced suppression of proliferative cues (e.g., extracellular-signal-regulated kinase) and initiation of apoptotic events. The nonnative form also showed better antitumorigenic properties, as evaluated using an induced two-stage mouse skin papilloma model. In contrast, the nonnative state showed only a fraction of the proteolytic activity of the native form. This study demonstrates that hexafluoroisopropanol can induce a conformational change in stem bromelain to a form with potentially useful therapeutic properties different from those of the native protein.