Gaurav Sharma

Bio: Gaurav Sharma is an academic researcher from Shenzhen University. The author has contributed to research in topics: Medicine & Photocatalysis. The author has an hindex of 82, co-authored 1244 publications receiving 31482 citations. Previous affiliations of Gaurav Sharma include Northeastern University & D. E. Shaw & Co..

Efficacy of Neoadjuvant Versus Adjuvant Therapy for Resectable Pancreatic Adenocarcinoma: A Decision Analysis

Abstract: Neoadjuvant therapy-based protocols for potentially resectable pancreatic adenocarcinoma (PAC) have not been directly compared with adjuvant protocols in large prospective randomized trials. This study aimed to compare the efficacy of neoadjuvant versus adjuvant therapy-based management by using a formal decision analytic model. A decision analytic model was created with a Markov process to compare neoadjuvant and adjuvant chemo- and/or chemoradiation therapy-based strategies for simulated cohorts of patients with potentially resectable PAC. Base-case probabilities were derived from the published data of 21 prospective phases 2 and 3 trials (3708 patients) between 1997 and 2014. The primary outcome measures determined in an intent-to-treat fashion were overall and quality-adjusted survival rates. One- and two-way sensitivity analyses were performed to assess the effects of model uncertainty on outcomes. The median overall survival and 2-year survival rates for the patients in the standard adjuvant therapy arm of the study were 20 months and 42.2 % versus 22 months and 46.8 % for those in the neoadjuvant strategy arm. Quality-adjusted survival was 18.4 and 19.8 months, respectively. Sensitivity analysis demonstrated that when recurrence-free survival after completion of neoadjuvant therapy and resection is less than 13.9 months or when the rate for progression of disease precluding resection during neoadjuvant therapy is greater than 44 %, the neoadjuvant strategy is no longer the favored option. The decision analytic model suggests that neoadjuvant therapy-based management improves the outcomes for patients with potentially resectable pancreatic cancer. However, the benefits in terms of overall and quality-adjusted survival are modest.

Biomedical applications of nano-antioxidant

Abstract: For centuries now, antioxidants have been known to provide better health by neutralizing the free radicals which are continuously produced in the human body. In normal circumstances, self-antioxidant defense system of the human body is capable of quantitatively managing the free radicals. However, in certain cases, which are at the threshold of developing diseases like diabetes and Alzheimer's, the human body calls for an external source of antioxidants. Since orally delivered antioxidants are easily destroyed by acids and enzymes present in the human system, only a small portion of what is consumed actually gets absorbed. Hence, there is a recognized and urgent need to develop effective methods for efficiently delivering antioxidants to the required sites. This chapter provides an in-depth overview and analysis of two such methods and processes-nano-encapsulation and nano-dendrimers. Among the various nanoscale delivery mechanisms, nano-encapsulation has emerged as a key and efficient delivery process. Designed as a spongelike polymer, nano-encapsulated antioxidants provide a protective vehicle which keeps antioxidants from being destroyed in the human gut and ensures their better absorption in the digestive tract. In fact, the nano-capsules bind themselves to the intestinal walls and pour antioxidants directly into the intestinal cells, which allow them to be absorbed directly into the blood stream. Another distinguished and popular mode for delivering antioxidants is that of nano-polymers known as dendrimers. Dendrimers involve multiple branches and sub-branches of atoms radiating out from a central core. Dendrimers afford a high level of control over their architectural design, including their size, shape, branching length or density, and surface functionality. Such flexibility makes these nanostructures ideal carriers in biomedical applications such as drug delivery, gene transfection, and imaging. Antioxidant dendrimers, made out of numerous units of antioxidants connected with each other in a branched fashion, provide numerous possible sites to couple with an active species and have enhanced free radicals scavenging potency. These dendrimer chains are biocompatible, biodegradable with nontoxic degradation products, and well suited for targeted drug delivery and other biomedical applications. Recent successes in simplifying and optimizing the synthesis of dendrimers, such as the "lego" and "click" approaches, provide a large variety of structures while at the same time reducing the cost of their production. The use of these highly branched, nanometer-sized, polymeric materials as nano-antioxidants for prevention and treatment of human diseases, associated with oxidative stress, is of immense public health relevance globally.

Carboxymethyl cellulose structured nano-adsorbent for removal of methyl violet from aqueous solution: isotherm and kinetic analyses

Abstract: In the present study, we have synthesized a nano-adsorbent of carboxymethyl cellulose; carboxymethyl cellulose/graphitic-carbon nitride/zinc oxide (CMC/g-C3N4/ZnO) by sol–gel technique. It has been utilized for the adsorptional elimination of methyl violet (MV) from aqueous solution. Maximum surface area as determined from the BET analyses is 9.214 m2/g. XRD analysis confirmed the semi-crystalline nature of the nano-adsorbent. Presence of desired functionalities on the surface of nano-adsorbent, CMC/g-C3N4/ZnO offered maximum interactions with the MV molecules. Isotherm studies generalized the monolayer adsorption of MV molecules with maximum adsorption capacity of 96.43 mg/g. Solution pH affected the adsorption rate to large extent and maximum occurred at pH 8. Pseudo-second order model better explained the adsorption process that determines the chemical interactions between methyl violet and CMC/g-C3N4/ZnO.

I and i

Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

SPAdes, a new genome assembly algorithm and its applications to single-cell sequencing ( 7th Annual SFAF Meeting, 2012)

Abstract: The lion's share of bacteria in various environments cannot be cloned in the laboratory and thus cannot be sequenced using existing technologies. A major goal of single-cell genomics is to complement gene-centric metagenomic data with whole-genome assemblies of uncultivated organisms. Assembly of single-cell data is challenging because of highly non-uniform read coverage as well as elevated levels of sequencing errors and chimeric reads. We describe SPAdes, a new assembler for both single-cell and standard (multicell) assembly, and demonstrate that it improves on the recently released E+V-SC assembler (specialized for single-cell data) and on popular assemblers Velvet and SoapDeNovo (for multicell data). SPAdes generates single-cell assemblies, providing information about genomes of uncultivatable bacteria that vastly exceeds what may be obtained via traditional metagenomics studies. SPAdes is available online ( http://bioinf.spbau.ru/spades ). It is distributed as open source software.