Modern seafood processing practices result in amassment of a large volume of waste products, i.e., skin, head, tails, shells, scales, backbones, etc. These waste products may often encompass several high-value products which are still untapped due to the dearth of appropriate management. Moreover, inadequate disposal of waste also has negative implications on both environment and human health. This seafood waste often contains a huge amount of chitin, a polysaccharide that exhibits exceptional inherent characteristics including biocompatibility, biodegradability, antimicrobial, antitumor and antioxidant activities. The present review summarizes the existing methods for recovery of chitin and its derivatives from marine waste. The preparation of chitin nanoparticles was discussed along with blending of chitin and chitosan with other biopolymers. The recent trends of the application of chitin and chitosan nanostructures in various sectors were explored. This review is an attempt to highlight the extraction methods of chitin and chitosan from marine waste resources and its transformation into valuable commercial products as a solution to waste management.

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We show, for the first time, that the tumor suppressor PTEN can have tumor-promoting properties. We show that PTEN acquires these unexpected properties by enhancing gainof-function mutant p53 (mut-p53) protein levels. We find that PTEN restoration to cells harboring mut-p53 leads to induction of G 1 -S cell cycle progression and cell proliferation and to inhibition of cell death. Conversely, PTEN inhibition in cells expressing wild-type PTEN and mut-p53 leads to inhibition of cell proliferation and inhibition of in vivo tumor growth. We show the dependency of the tumor-promoting effects of PTEN on mut-p53 by showing that knockdown of mut-p53 expression inhibits or reverses the tumor-promoting effects of PTEN. Mechanistically, we show that PTEN expression enhances mut-p53 protein levels via inhibition of mutp53 degradation by Mdm2 and possibly also via direct protein binding. These findings describe a novel function of PTEN and have important implications for experimental and therapeutic strategies that aim at manipulating PTEN or p53 in human tumors. They suggest that the mutational status of PTEN and p53 should be considered to achieve favorable therapeutic outcomes. The findings also provide an explanation for the low frequency of simultaneous mutations of PTEN and p53 in human cancer.

Crop cultivation is crucial for the existence of human beings, as it fulfills our nutritional requirements. Crops and other plants are always at a high risk of being attacked by phytopathogens, especially pathogenic fungi. Although plants have a well-developed defense system, it can be compromised during pathogen attack. Chitinases can enhance the plant's defense system as they act on chitin, a major component of the cell wall of pathogenic fungi, and render the fungi inactive without any negative impact on the plants. Along with strengthening plant defense mechanisms, chitinases also improve plant growth and yield. Chitinases in combination with recombinant technology can be a promising tool for improving plant resistance to fungal diseases. The applicability of chitinase-derived oligomeric products of chitin further augment chitinase prospecting to enhance plant defense and growth.

BackgroundTuberculosis (TB) is the most threatening infectious disease globally. Although progress has been made to reduce global incidence of TB, emergence of multidrug resistant (MDR) TB threatens to undermine these advances. To combat the disease, novel intervention strategies effective against drug resistant and sensitive subpopulations of M. tuberculosis are urgently required as adducts in the present treatment regimen. Using THP-1 cells we have analyzed and compared the global protein expression profile of broth-cultured and intraphagosomally grown drug resistant and sensitive M.tuberculosis clinical isolates.ResultsOn comparing the two dimensional (2-DE) gels, many proteins were found to be upregulated/expressed during intracellular state which were identified by matrix assisted laser desorption/ionization mass spectrometry (MALDI-MS). Four proteins (adenosylhomocysteinase, aspartate carbomyltransferase, putatitive thiosulfate sulfurtransferase and universal stress protein) were present in both intracellular MDR and sensitive isolates and three of these belonged to intermediary metabolism and respiration category. Two proteins (alanine dehydrogenase and adenosine kinase) of intracellular MDR isolate and two (glucose-6-phosphate isomerase and ATP synthase epsilon chain) of intracellular sensitive isolate belonged to intermediary metabolism and respiration category. One protein (Peroxidase/Catalase) of intracellular MDR and three (HSPX, 14 kDa antigen and 10 kDa chaperonin) of sensitive isolate belonged to virulence, detoxification and adaptation category. ESAT-6 of intracellular MDR belonged to cell wall and cell processes category. Two proteins (Antigen 85-C and Antigen 85-A) of intracellular sensitive isolate were involved in lipid metabolism while probable peptidyl-prolyl cis-trans isomerase A was involved in information pathways. Four (Rv0635, Rv1827, Rv0036c and Rv2032) of intracellular MDR and two proteins (Rv2896c and Rv2558c) of sensitive isolate were hypothetical proteins which were functionally characterized using bioinformatic tools. Bioinformatic findings revealed that the proteins encoded by Rv0036, Rv2032c, Rv0635, Rv1827 and Rv2896c genes are involved in cellular metabolism and help in intracellular survival.ConclusionsMass spectrometry and bioinformatic analysis of both MDR and sensitive isolates of M. tuberculosis during intraphagosomal growth showed that majority of commonly upregulated/expressed proteins belonged to the cellular metabolism and respiration category. Inhibitors of the metabolic enzymes/intermediate can therefore serve as suitable drug targets against drug-resistant and sensitive subpopulations of M. tuberculosis.

Osteoarthritis (OA), a common musculoskeletal disorder, is projected to affect about 60 million people of total world population by 2020. The associated pain and disability impair the quality of life and also pose economic burden to the patient. Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely prescribed in OA, while diclofenac is the most prescribed one. Oral NSAIDs are not very patient friendly, as they cause various gastrointestinal adverse effects like bleeding, ulceration, and perforation. To enhance the tolerability of diclofenac and decrease the common side effects, aceclofenac (ACE) was developed by its chemical modification. As expected, ACE is more well-tolerated than diclofenac and possesses superior efficacy but is not completely devoid of the NSAID-tagged side effects. A series of chemical modifications of already planned drug is unjustified as it consumes quanta of time, efforts, and money, and this approach will also pose stringent regulatory challenges. Therefore, it is justified to deliver ACE employing tools of drug delivery and nanotechnology to refine its safety profile. The present review highlights the constraints related to the topical delivery of ACE and the various attempts made so far for the safe and effective topical delivery employing the novel materials and methods.

Bile salt hydrolase (BSH) activity, hypo-cholesterolemic effect, and probiotic properties have been reported for Enterococcus strains isolated from animal and human gut and fermented foods but not for strains isolated from environmental niches, like aquatic and terrestrial plants, soil, and water. The present study is the first report on isolation of Enterococcus faecium from rhizospheric soils that harbor the bsh gene, remove cholesterol in vitro , and possess essential and desirable probiotic attributes. Fifteen samples were collected from different sites located in northern, southern, and central regions of India, of which five yielded pure colonies that were named LR2, LR3, ER5, LR13, and VB1. These were identified by 16S rRNA gene sequencing as E. faecium and evaluated for BSH activity, cholesterol-lowering potential in vitro , and probiotic properties. Our results indicated that all the strains were capable of surviving the harsh conditions of the gastrointestinal tract and did not harbor any of the virulence genes. Though all strains showed the presence of bsh and potential for cholesterol removal, E. faecium strain LR13 showed a remarkable cholesterol removal capability and vancomycin susceptibility and possessed most of the desirable and essential attributes of a probiotic. Hence, it seems to be a fairly promising probiotic candidate that needs to be further evaluated in in vivo studies, especially for its hypo-cholesterolemic potential.

Nanotechnology-based drug products are emerging as promising agents to enhance the safety and efficacy of established chemotherapeutic molecules. Carbon nanotubes (CNTs), especially multiwalled CNTs (MWCNTs), have been explored for this potential owing to their safety and other desired attributes. Docetaxel (DTX) is an indispensable anticancer agent, which has wide applicability in variety of cancers. However, the potential of DTX is still not completely harvested due to problems like poor aqueous solubility, low tissue permeability, poor bioavailability, high first pass metabolism, and dose-related toxicity. Hence, it was proposed to attach DTX to MWCNTs and coadminister it along with piperine with an aim to enhance the tissue permeation, anticancer activity, and bioavailability. The Fourier transform infrared, UV, and NMR spectroscopic data confirmed successful conjugation of DTX to MWCNTs and adsorption of piperine onto MWCNTs. The codelivery MWCNT-based system offered drug release moderation and better cancer cell toxicity than that of plain DTX as well as DTX-CNT conjugate. The pharmacokinetic profile of DTX was exceptionally improved by the conjugation, in general, and coadministration with piperine, in specific vis-à-vis plain drug. Hence, the dual approach of MWCNTs conjugation and piperine coadministration can serve as a beneficial option for enhancement of the performance of DTX in cancer chemotherapy.