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Background: Chalcones are structurally simple compounds that are easily accessible by synthetic methods. Heterocyclic chalcones have gained the interest of scientists due to their diverse biological activities. The anti-tumor activities of heterocyclic chalcones are especially remarkable and the growing number of publications dealing with this topic warrants an up-to-date compilation. Methods: Search for antitumor active heterocyclic chalcones was carried out using Pubmed and Scifinder as common web-based literature searching tools. Pertinent and current literature was covered from 2015/2016 to 2019. Chemical structures, biological activities and modes of action of anti-tumor active heterocyclic chalcones are summarized. Results: Simply prepared chalcones have emerged over the last years with promising antitumor activities. Among them, there are a considerable number of tubulin polymerization inhibitors. But there are also new chalcones targeting special enzymes such as histone deacetylases or with DNA-binding properties. Conclusion: This review provides a summary of recent heterocyclic chalcone derivatives with distinct antitumor activities.

ABSTRACTIntroduction: More than 50% of the clinically established antibiotics are either genuine natural products or derivatives thereof, featuring a mode of action decisively depending on their metal affinity and suitability as metal complex ligands. As their structural diversity and harvest from renewable sources is well-nigh inexhaustible, any future quest for affordable new antibiotics will have to concentrate on natural drugs with obvious metal ligating properties.Areas covered: The authors provide an overview of the promising developments in the field of antibiotic natural products with metal-binding properties with a specific focus on metal binders such as polyphenols, quinones, 3-acyltetramic and -tetronic acids. Works published by the authors are discussed in this manuscript as well as articles derived from PubMed and Scifinder.Expert opinion: Natural products with metal-binding properties possess a great potential for the development of drugs against various bacteria. There are many derivatives with great potential against multidrug-resistant bacteria as well. Synthetic approaches to structurally complex and/or rare natural products have added significantly to the cracking of synthetic problems. Thus, this field of scientific research appears attractive both to chemists and to clinicians.

Pancreatic ductal adenocarcinoma is one of the deadliest cancers worldwide and the fourth leading cause of cancer-related deaths in United States. Regardless of the advances in molecular pathogenesis and consequential efforts to suppress the disease, this cancer remains a major health problem in United States. By 2030, the projection is that pancreatic cancer will be climb up to be the second leading cause of cancer-related deaths in the United States. Pancreatic cancer is a rapidly invasive and highly metastatic cancer, and does not respond to standard therapies. Emerging evidence supports that the presence of a unique population of cells called cancer stem cells (CSCs) as potential cancer inducing cells and efforts are underway to develop therapeutic strategies targeting these cells. CSCs are rare quiescent cells, and with the capacity to self-renew through asymmetric/symmetric cell division, as well as differentiate into various lineages of cells in the cancer. Studies have been shown that CSCs are highly resistant to standard therapy and also responsible for drug resistance, cancer recurrence and metastasis. To overcome this problem, we need novel preventive agents that target these CSCs. Natural compounds or phytochemicals have ability to target these CSCs and their signaling pathways. Therefore, in the present review article, we summarize our current understanding of pancreatic CSCs and their signaling pathways, and the phytochemicals that target these cells including curcumin, resveratrol, tea polyphenol EGCG (epigallocatechin- 3-gallate), crocetinic acid, sulforaphane, genistein, indole-3-carbinol, vitamin E δ- tocotrienol, Plumbagin, quercetin, triptolide, Licofelene and Quinomycin. These natural compounds or phytochemicals, which inhibit cancer stem cells may prove to be promising agents for the prevention and treatment of pancreatic cancers.

Due to intense use of digital visual aids, image quality plays a crucial role in today's life. Images are subjected to degradations during image acquisition and image processing. This affects their naturalness and usefulness in different applications. Literature shows efforts are made to develop an HVS consistent image quality metric since last few decades. New image quality metrics, extension of existing image quality algorithms and their applications are being developed by researcher's community. Singular value decomposition is one of the measures which are used to quantify the amount of distortion at different distortion levels. Based on the hypothesis that the human eye is adapted to extract edge information from any natural scene, this paper presents a novel approach of introducing edge information in SVD-based image quality metric. The results are compared with SVD-based metric available in related work in literature. Proposed metric outperforms the existing metric. Also, it is extended for evaluation of colour images.

The authentication system used at the automated teller machines (ATM) is a unique personal identification number (PIN). This PIN can be easily tapped and misused. In this paper we propose a method in which the PIN is replaced by the biometrics of the individual to have a more secure transaction. A complete hardware system is designed to capture the biometric traits such as face, fingerprint and palm vein. The captured images are pre-processed and then features are extracted which are then fused at feature level. Cryptography is applied on the fused feature vector. Matching is performed using Euclidean distance at the server end. Palm vein is particularly chosen as a biometric trait along with widely used face and fingerprint because it is unique and is impossible to forge the vein pattern of an individual. Curvelet and Wavelet Transforms are used for the feature extraction. Experimental results indicate a good level of security and recognition rate of 91% and 89% is achieved on our own generated database. The results are promising when compared with other existing similar techniques.

Today's world has witnessed tremendous increase in use of multimedia and internet. This demands an image quality metric capable of evaluating image quality, accurately and automatically. Natural scenes are of excellent quality and all natural scenes exhibit similar statistical properties. Natural scene statistics is successfully used in image quality assessment which is based on the hypothesis that introduction of distortion in an image causes deviation from statistical properties. Amount of deviation in the statistical property of an image is found to be proportional to the amount of distortion. A neural network-based image quality metric needs such natural scene statistical feature to predict the image quality blindly. This paper presents a new feature for colour image quality assessment that is extracted after decomposing given image into different frequency bands of hue plane. In future, this feature will be used in a classifier to evaluate colour image quality.

Images are compressed using lossy compression for fast transmission and efficient storage. Due compression artefacts quality of images are degraded. In web application, unavailability of an original image is a major challenge to evaluate quality of images. Therefore there is an immense need to develop a quality metric that will automatically assess quality without referring the original image. In this paper, no reference image quality assessment scheme using the machine learning approach is proposed. The block-based features brightness, contrast, local amplitude, texture and other parameters of the degraded images are calculated along with first order and second order statistical features in frequency domain. These features are given as inputs to well-trained back propagation neural network whose output is a quality score. The mean opinion score is used as target. The result indicates that accuracy of quality assessment is better in comparison with traditional mathematical predictors.

Curcumin is the active component of dried rhizome of Curcuma longa, a perennial herb belonging to ginger family, cultivated extensively in south and southeastern tropical Asia. It is widely consumed in the Indian subcontinent, south Asia and Japan in traditional food recipes. Extensive research over last few decades has shown that curcumin is a potent anti-inflammatory agent with powerful therapeutic potential against a variety of cancers. It suppresses proliferation and metastasis of human tumors through regulation of various transcription factors, growth factors, inflammatory cytokines, protein kinases and other enzymes. It induces apoptotic cell death and also inhibits proliferation of cancer cells by cell cycle arrest. Pharmacokinetic data has shown that curcumin undergoes rapid metabolism leading to glucuronidation and sulfation in the liver and excretion in the feces, which accounts for its poor systemic bioavailability. The compound has, therefore, been formulated and administered using different drug delivery systems such as liposomes, micelles, polysaccharides, phospholipid complexes and nanoparticles that can overcome the limitation of bioavailability to some extent. Attempts to avoid rapid metabolism of curcumin until now have been met with limited success. This has prompted researchers to look for new synthetic curcumin analogs in order to overcome the drawbacks of limited bioavailability and rapid metabolism, and gain efficacy with reduced toxicity. In this review we provide a summarized account of novel synthetic curcumin formulations and analogs, and the recent progress in the field of cancer prevention and treatment.

Nature has been a rich source of therapeutic agents for thousands of years and an impressive number of modern drugs have been isolated from natural sources based on the uses of these plants in traditional medicine. Henna is one such plant commonly known as Persian Henna or Lawsonia inermis, a bushy, flowering tree, commonly found in Australia, Asia and along the Mediterranean coasts of Africa. Paste made from the leaves of Henna plant has been used since the Bronze Age to dye skin, hairs and fingernails especially at the times of festivals. In recent times henna paste has been used for body art paintings and designs in western countries. Despite such widespread use in dyeing and body art painting, Henna extracts and constituents possess numerous biological activities including antioxidant, anti-inflammatory, antibacterial and anticancer activities. The active coloring and biologically active principle of Henna is found to be Lawsone (2- hydroxy-1, 4-naphthoquinone) which can serve as a starting building block for synthesizing large number of therapeutically useful compounds including Atovaquone, Lapachol and Dichloroallyl lawsone which have been shown to possess potent anticancer activities. Some other analogs of Lawsone have been found to exhibit other beneficial biological properties such as antioxidant, anti-inflammatory, antitubercular and antimalarial. The ability of Lawsone to undergo the redox cycling and chelation of trace metal ions has been thought to be partially responsible for some of its biological activities. Despite such diverse biological properties and potent anticancer activities the compound has remained largely unexplored and hence in the present review we have summarized the chemistry and biological activities of Lawsone along with its analogs and metal complexes.

Benzoquinones are class of natural quinones found chiefly in higher plants, fungi, bacteria and animal kingdom. They are involved in important biological functions such as bioenergetic transport, oxidative phosphorylation and electron transport processes. In recent years it has become increasingly clear that some of them possess potent antioxidant, anti-inflammatory and anticancer activities. There is clearly a common thread running through these activities and there have been a large number of studies carried out to unravel the mechanisms of these activities. In the present review we have provided a brief account of these studies especially covering these aspects. Although antioxidant potentials of these compounds constitute the basis of their biological activities its nature and scope is dictated by many microscopic biological environments. One of the important advantages offered by these compounds is the ease with which they can be synthesized and chemically manipulated. This can easily provide impetus for further research in developing some potentially useful drug molecules.

Prone position ventilation (PPV) is resource-intensive, yet the optimal strategy for PPV in intubated patients with COVID-19 is unclear.

Introduction:CT imaging is the primary mode of diagnosis of acute pulmonary embolus. At initial presentation, both patients with acute PE and undiagnosed decompensated CTEPH may present with similar clinical findings of presence of clot and RV dysfunction. Extraction of markers of disease from CT scans at the point of diagnosis may help with clinical decision making. In this study we compare two CT markers of disease severity in patients with submassive PE and CTEPH. We hypothesized that higher pressures and thus increased dilation of the pulmonary artery would be hemodynamically tolerated in the chronic disease.Methods:We conducted a retrospective chart review study at Brigham and Women’s Hospital for patients with acute submassive PE between 2009-2017. Patients with adequate imaging and at least one positive right ventricular echocardiogram findings were included. The CTEPH cohort consisted of patients with CT imaging within one year of RHC proven CTEPH and patients from the submassive PE cohort found to have subsequently been diagnosed with CTEPH. The ratio of the main pulmonary artery (PA) to aorta (A) and RV to LV diameter ratio were measured by multiple operators to confirm reproducibility. All data collection was approved by the IRB at Mass General Brigham. Data was analyzed using R version 4.0.1 and Wilcoxon Rank-sum test with two-sided p-values for differences. Medians and interquartile ranges are reported.Results:355 patients with the diagnosis of acute submassive PE and positive echo findings and 31 patients with CTEPH were included. Patients with acute PE were older (63 [53-73] vs 48 [41-67] p= 0.003) and had a similar fraction of females (190/355 vs 17/31). PAA was significantly higher in the CTEPH cohort (1.16 [0.97-1.32] vs 0.94 [0.85-1.04] p < 0.0001) as was the RV/LV ratio (1.44 [1.34-1.57] vs 1.31 [1.16-1.46]; p = 0.0005).Conclusions:Patients with CTEPH have a higher PA/A ratio than patients with submassive PE and echocardiographic signs of RV dysfunction. This study is limited in part because of the time between imaging and diagnosis of CTEPH, and lack of definitive follow-up for all acute PE cases. Prospective data collection would help evaluate clinical utility of CT markers in identifying chronic disease.

During a brief period from March 1988 to January 1990 we were faced with 13 patients with malignant vertebral neoplasms (metastasis) of the thoracic spine. Nine of these had progressive extradural spinal cord compression with motor, sensory and sphincter involvement of varying degrees and duration. After proper evaluation these 9 cases were aggressively managed by preoperative embolisation of the tumour, transpedicular decompression and a same stage posterior metallic fixation. The immediate results were encouraging, with 2 patients showing total recovery and 3 showing partial recovery. All of the 9 operated cases were pain free postoperatively and could sit up unaided and be easily transferred to the Cancer Institute for back up chemotherapy and radiotherapy. They also improved psychologically, and cooperated well in their subsequent rehabilitation programme.