444 research outputs found
An Experimental and Computational Study of 2-(3-Oxo-3H-benzof chromen-1-ylmethoxy)-Benzoic Acid Methyl Ester
The various methods for studying polarities are based on the use of probe molecules, whose molecular spectral profile is significantly affected by the polarity of the medium. The absorption and emission spectra and dipole moments (µg and µe) of 2-(3-oxo-3H-benzofchromen-1-ylmethoxy)-benzoic acid methyl ester (2BME) are studied in solvents of different polarities at room temperature. The determination of dipole moments by solvatochromic shift using various relations and the change in dipole moment (�µ) were determined using Stokes shift with the variation of the solvent polarity parameter (ET N). The value of µe greater than µg indicating that the probe is more polar in the higher state. DFT and TDDFT theoretical analysis of dipole moment in the vacuum and with solvent, solvent accessible surface (SAS) and molecular electrostatic potential (MEP) are also performed. © 2017, Springer Science+Business Media, LLC
Synthesis and Biological Evaluation of 4-(3-Hydroxy-Benzofuran-2-yl) Coumarins
Various 4-bromomethylcoumarins (1a-k) were reacted with methyl salicylate to yield 2-(2-oxo-2H-chromen-4-ylmethoxy)-benzoic acid methyl esters (2a-k). Formations of (3a-k) were achieved by using DBU under microwave irradiation. Structures of all the compounds were established on the basis of their spectral data. All the compounds were tested in vitro for their antimicrobial activity and cell cytotoxicity. All the tested compounds (2b-k) and (3a-k) were shown to be better activity against Staphylococcus aureus than the standard Ciprofloxacin. The compound (3k) (R = 6-OMe) was found to be more potent cytotoxic than the standard 5-fluorouracil
InCl3-assisted synthesis and cytotoxic studies of some novel heteroaryl thiazoles
Heteroaryl thiazoles were synthesized by the Hantzsch reaction of various α-bromoketones with aryl thioureas using InCl3 as a catalyst in a shorter reaction time. The synthesized compds. were characterized and screened for their in-vitro cytotoxic activity against DAL and EAC cells. Compd. I was found to be most effective against DAL cell lines with IC50 value of 15.76 μg/mL. Compd. II was found to be most effective against EAC cells with IC50 value of 28.73 μg/mL
Thermodynamic Modeling and Analysis of Human Stress Responses
A novel approach based on the second law of thermodynamics is developed to investigate the psychophysiology and quantify human stress level. Two types of stresses (thermal and mental) are examined. A Unified Stress Response Theory (USRT) is developed under the new proposed field of study called Engineering Psychophysiology. The USRT is used to investigate both thermal and mental stresses from a holistic (human body as a whole) and thermodynamic viewpoint. The original concepts and definitions are established as postulates which form the basis for thermodynamic approach to quantify human stress level. An Objective Thermal Stress Index (OTSI) is developed by applying the second law of thermodynamics to the human thermal system to quantify thermal stress or discomfort in the human body. The human thermal model based on finite element method is implemented. It is utilized as a “Computational Environmental Chamber” to conduct series of simulations to examine the human thermal stress responses under different environmental conditions. An innovative hybrid technique is developed to analyze human thermal behavior based on series of human-environment interaction simulations. Continuous monitoring of thermal stress is demonstrated with the help of OTSI. It is well established that the human thermal system obeys the second law of thermodynamics. Further, the OTSI is validated against the experimental data. Regarding mental stress, an Objective Mental Stress Index (OMSI) is developed by applying the Maxwell relations of thermodynamics to the combined thermal and cardiovascular system in the human body. The OMSI is utilized to demonstrate the technique of monitoring mental stress continuously and is validated with the help of series of experimental studies. Although the OMSI indicates the, level of mental stress, it provides a strong thermodynamic and mathematical relationship between activities of thermal and cardiovascular systems of the human body
Adaptive filters based efficient EEG classification for steady state visually evoked potential based BCI system
Brain-computer interfaces (BCIs) system is a link to generate a communication between disable people and physical devices. Thus, steady state visually evoked potential (SSVEP) is analysed to improve performance efficiency of BCIs system using multi-class classification process. Thus, an adaptive filtering-based component analysis (AFCA) method is adopted to examine SSVEP from multiple-channel electroencephalography (EEG) signals for BCIs system efficiency enhancement. Further, flickering at varied frequencies is used in a visual stimulation process to examine user intentions and brain responses. A detailed solution for optimization problem and efficient feature extraction is also presented. Here, a large SSVEP dataset is utilized which contains 256 channel EEG data. Experimental results are evaluated in terms of classification accuracy and information transfer rate to measure efficiency of proposed SSVEP extraction method against varied traditional SSVEP-based BCIs. The average information transfer rate (ITR) results are 308.23 bits per minute and classification accuracy is 93.48% using proposed AFCA method. Thus, proposed AFCA method shows decent performance in comparison with state-of-art-SSVEP extraction methods
Key role of orthopaedician and radiologist in successful management of fat embolism syndrome
Fat embolism syndrome (FES) is an emergency fatal condition, if not diagnosed early and timely managed. Careful observation of patients with multiple bone fractures aids in early diagnosis. Rehydration is an important factor in preventing FES. Most often the syndrome is self-limiting. High risk cases are treated with steroids and with respirator assistance
Efficient matrix key homomorphic encryption of medical images
A sure way of providing privacy to sensitive images is to encrypt them, especially when they are stored in a public cloud server. Homomorphic encryption enables arithmetic operations over encrypted data without access to the secret key. This facility can be well harnessed for secure outsourced image processing by exploiting the available computational capabilities of modern cloud servers. This paper presents a new homomorphic image encryption scheme that uses integer matrix keys. The homomorphic operations are carried out in the finite field Zp to avail the advantages of integer arithmetic and to limit the cipher text sizes to reasonable levels. Our method does not use any error vector as in learning with errors (LWE) to improve the security
The transcription factor RUNX2 regulates receptor tyrosine kinase expression in melanoma.
Receptor tyrosine kinases-based autocrine loops largely contribute to activate the MAPK and PI3K/AKT pathways in melanoma. However, the molecular mechanisms involved in generating these autocrine loops are still largely unknown. In the present study, we examine the role of the transcription factor RUNX2 in the regulation of receptor tyrosine kinase (RTK) expression in melanoma. We have demonstrated that RUNX2-deficient melanoma cells display a significant decrease in three receptor tyrosine kinases, EGFR, IGF-1R and PDGFRβ. In addition, we found co-expression of RUNX2 and another RTK, AXL, in both melanoma cells and melanoma patient samples. We observed a decrease in phosphoAKT2 (S474) and phosphoAKT (T308) levels when RUNX2 knock down resulted in significant RTK down regulation. Finally, we showed a dramatic up regulation of RUNX2 expression with concomitant up-regulation of EGFR, IGF-1R and AXL in melanoma cells resistant to the BRAF V600E inhibitor PLX4720. Taken together, our results strongly suggest that RUNX2 might be a key player in RTK-based autocrine loops and a mediator of resistance to BRAF V600E inhibitors involving RTK up regulation in melanoma
Comprehensive Literature Review and Evidence evaluation of Experimental Treatment in COVID 19 Contagion
Importance: Coronavirus 2019 pandemic (COVID 19) is caused by the Severe acute respiratory syndrome coronavirus 2 (SARS CoV-2) virus. The pandemic is affecting the livelihood of millions of people all over the world. At the time of preparing this report, the pandemic has affected 1 827 284 patients, with 113 031 deaths in 185 countries as per Johns Hopkins University. With no proven treatment for the disease, prevention of the disease in the community and healthcare setting is need of the hour.
Objective: To perform a comprehensive literature search for preventive measures and experimental treatment options. In this review, we have focused our discussion on the risk of disease transmission, supportive treatment, and possible treatment options based on available evidence.
Evidence Review: We performed a literature search on google scholar, PubMed, and society guidelines for literature related to COVID 19 and previous coronavirus pandemics. We included data review articles, observational studies, and controlled trials to synthesize the treatment options for COVID 19.
Findings: In this article, we have extensively reviewed and discussed recommendations from various world organizations for the public and healthcare workers. We have also discussed currently available experimental treatments since there is no proven treatment for COVID 19. The best method of dealing with the current outbreak is to reduce the community spread and thus “flatten the curve.” Although Hydroxychloroquine, Remdesivir, Lopinavir/Ritonavir, and Azithromycin have been tried, passive immunity through convalescent serum and vaccine is still at an experimental stage. Patients with severe COVID 19 infections could be considered for this experimental treatment through various national randomized control trials, which may eventually lead to an evidence-based treatment strategy.
Conclusions and Relevance: Awareness of currently available experimental treatment among healthcare providers and exploration of possible treatment options through evidence is need of the hour. We have discussed the most recently available literature and evidence behind experimental treatment in this article
- …
