Chitosan-Based Nanocomposites for Biological Applications

Chitosan is an important natural cationic polymer. Chitosan is produced as a deacetylated form of chitin, and its excellent biocompatible, biodegradable, nontoxic, natural chemical, and thermal stability properties have led to its common use in especially biomedical applications. The combination of nanomaterials and chitosan has been considered an excellent approach to overcoming the handicaps associated with biopolymer. The chitosan-based nanocomposites are potentially efficient in a number of areas including medical fields. Chitosan is biodegradable, biocompatible, basic, nontoxic, and also approved by GRAS (Generally recognized as safe by the United States Food and Drug Administration [US FDA]). Chitosan-based nanocomposites have different applications in drug delivery including ocular, per-oral, pulmonary, nasal mucosal, gene, buccal drug, vaccine, vaginal, and cancer therapy. Chitosan has low toxicity in both in vitro and in vivo models. In this chapter, we discussed the preparation techniques and various forms of chitosan materials in biomedical applications. In addition, this chapter explores recent research on chitosan-based nanocomposites for medical studies

Effectiveness of Cognitive Behavioral Group Therapy for Treatment of Social Phobia in Adults: A Systematic Review

This study aims to review empirical studies that were used to evaluate the effectiveness of cognitive-behavioral group therapy programs for the treatment of social phobia (social anxiety disorder) in adults. Articles in English and Turkish that were published between the years of 2005 and 2015 have been searched in the national and international databases. The articles that were not therapy effec-tiveness studies, and group therapies that not based on cognitive behavioral approach, researches that examined different disorder apart from social phobia were eliminated. The remaining 27 studies that met the criteria were introduced in the context of method, therapy characteristics and results. Findings of articles revealed that cognitive behavior group therapy for social phobia decreases social phobia symptoms and improves the quality of life in adults. [Psikiyatride Guncel Yaklasimlar - Current Approaches in Psychiatry 2016; 8(Supplement 1): 61-78

Investigation of the Therapeutic Effects of Palbociclib Conjugated Magnetic Nanoparticles on Different Types of Breast Cancer Cell Lines

Introduction-Drug targeting and controlled drug release systems in cancer treatment have many advantages over conventional chemotherapy in terms of limiting systemic toxicity, side effects, and overcoming drug resistance.Methods and Results-In this paper, fabricating nanoscale delivery system composed of magnetic nanoparticles (MNPs) covered with poly-amidoamine (PAMAM) dendrimers and using its advantages were fully used to help the chemotherapeutic drug, Palbociclib, effectively reach tumors, specifically and stay stable in the circulation longer. In order to determine whether conjugate selectivity can be increased for the specific drug type, we have reported different strategies for loading and conjugation of Palbociclib to different generations of magnetic PAMAM dendrimers. The best method leading to the highest amount of Palbociclib conjugation was chosen, and the characterization of the Palbociclib conjugated dendrimeric magnetic nanoparticles (PALDcMNPs) were performed. In vitro pharmacological activity of the conjugation was demonstrated by measuring the cell viability and lactate dehydrogenase (LHD) release. Obtained results indicated that PAL-DcMNPs treatment of the breast cancer cell lines, leads to an increase in cell toxicity compared to free Palbociclib. The observed effects were more evident for MCF-7 cells than for MDA-MB231 and SKBR3 cells, considering that viability decreased to 30% at 2.5 lM treatment of PAL-DcMNPs at MCF-7 cells. Finally, in Palbociclib and PAL-DcMNPs treated breast cancer cells, the expression levels of some pro-apoptotic and drug resistance related genes were performed by RT-PCR analysis.Conclusion-Our knowledge indicates that the proposed approach is novel, and it can provide new insight into the development of Palbociclib targeting delivery system for cancer treatment

Synthesis and In vitro Antimicrobial Activity of Novel 2-(4-(Substituted-carboxamido)benzyl / phenyl)benzothiazoles

A new series of 2-[4-(4-substitutedbenzamido / phenylacetamido / phenylpropionamido) benzyl / phenyl]benzothiazole derivatives (6a−6w) were synthesized and evaluated for antibacterial and antifungal activities against Staphylococcus aureus, Bacillus subtilis, Klebsiella pneumoniae, Pseudomonas aeruginosa, Escherichia coli with their drug-resistant isolates and a yeast Candida albicans. Microbiological results indicated that the compounds possessed a broad spectrum of activity against the tested microorganisms at MIC values between 200 and 6.25 μg/ml. Compounds 6e and 6j exhibited the greatest activity with MIC values of 6.25 μg/ml against Pseudomonas aeruginosa, and Staphylococcus aureus isolate, respectively.(doi: 10.5562/cca2064

Graphene Oxide Nanosheets Interact and Interfere with SARS‐CoV‐2 Surface Proteins and Cell Receptors to Inhibit Infectivity

From Wiley via Jisc Publications RouterHistory: received 2021-03-13, pub-electronic 2021-05-14Article version: VoRPublication status: PublishedFunder: University of PaduaFunder: UKRI EPSRC; Grant(s): EP/P00119X/1Funder: Turkish Academy of Sciences (TUBA)Funder: Scientific and Technology Council of Turkey; Grant(s): 18AG020Funder: Türkiye Bilimler Akademisi; Id: http://dx.doi.org/10.13039/501100004412; Grant(s): GEBIP 2018Funder: Türkiye Bilimsel ve Teknolojik Araştirma Kurumu; Id: http://dx.doi.org/10.13039/501100004410; Grant(s): 18AG020Funder: Engineering and Physical Sciences Research Council; Id: http://dx.doi.org/10.13039/501100000266; Grant(s): EP/P00119X/1Abstract: Nanotechnology can offer a number of options against coronavirus disease 2019 (COVID‐19) acting both extracellularly and intracellularly to the host cells. Here, the aim is to explore graphene oxide (GO), the most studied 2D nanomaterial in biomedical applications, as a nanoscale platform for interaction with SARS‐CoV‐2. Molecular docking analyses of GO sheets on interaction with three different structures: SARS‐CoV‐2 viral spike (open state – 6VYB or closed state – 6VXX), ACE2 (1R42), and the ACE2‐bound spike complex (6M0J) are performed. GO shows high affinity for the surface of all three structures (6M0J, 6VYB and 6VXX). When binding affinities and involved bonding types are compared, GO interacts more strongly with the spike or ACE2, compared to 6M0J. Infection experiments using infectious viral particles from four different clades as classified by Global Initiative on Sharing all Influenza Data (GISAID), are performed for validation purposes. Thin, biological‐grade GO nanoscale (few hundred nanometers in lateral dimension) sheets are able to significantly reduce copies for three different viral clades. This data has demonstrated that GO sheets have the capacity to interact with SARS‐CoV‐2 surface components and disrupt infectivity even in the presence of any mutations on the viral spike. GO nanosheets are proposed to be further explored as a nanoscale platform for development of antiviral strategies against COVID‐19

Dextran-coated iron oxide nanoparticle for delivery of miR-29a to breast cancer cell line

WOS: 000473057000001PubMed ID: 31159615In the last years, miRNAs have been associated with molecular pathways of cancer and other diseases. The change of expression level of miRNA has an inhibitory role in tumorigenesis. Nevertheless, the poor bioavailability of miRNA due to the rapid enzymatic degradation is a critical handicap in cancer therapy. In this study, we designed dextran-coated iron oxide-based nanoparticle for the delivery of miR-29a to breast cancer cells and analyzed its therapeutic efficacy in vitro. Results indicated that the presence of dextran-coated magnetic nanoparticles, loaded with miR29a, enhanced the selective delivery of miR-29a. Further, miR-29a complex nanoparticles caused down-regulation of anti-apoptotic genes. These results pave the way for further investigations into the possible use of miR-29a complex magnetic nanoparticles for breast cancer therapy

Synthesis and biological activity of siRNA and Etoposide with magnetic nanoparticles on drug resistance model MCF-7 Cells: Molecular docking study with MRP1 enzyme

Objective(s): In this work, MRP-1 (Multidrug resistance-associated protein 1) gene expression levels and anticancer activity of siRNA and Etoposide loaded Poly-hydroxybutyrate (PHB) coated magnetic nanoparticles (MNPs) was studied on MCF-7/Sensitive and MCF-7/1000 Etoposide resistance cells. For this purpose, PHB covered iron oxide-based magnetic nanoparticles (PHB-MNPs) were prepared by coprecipitation. We used magnetic nanoparticles because they include highly targeted to tumors in vivo cancer therapy

BRAF mutation in colorectal carcinomas with signet ring cell component

WOS: 000417395100008PubMed ID: 28884045Objective: Signet ring cell carcinoma is a rare subtype of colorectal carcinoma (CRC) with an associated BRAFV600E mutation. We investigated frequencies of BRAF mutation in 28 CRCs containing variable signet ring cell component and their relation with clinicopathologic parameters. Methods: According to the presence of signet ring cell component, tumors were categorized into groups as follows: 0%-9%, 10%-24%, 25%-49%, and >50%. Genomic DNA was isolated and analyzed for BRAF V600E gene mutation by polymerase chain reaction-restriction fragment length polymorphism. Eleven of 28 cases (39.3%) showed BRAFV600E mutation, which was also confirmed by Sanger sequencing. To elucidate the importance of existence of signet ring cell component at the molecular level, we separated cases into two groups with cut-off levels of 10% and 50%, which pertain to percentages of signet ring cells. Results: Seven of 19 cases (36.8%) under the threshold of 50% and four of nine cases (44.4%) over this threshold value demonstrated BRAF mutation. Three of 7 cases (42.8%) featuring 10% were BRAF mutated. Conclusions: BRAF mutation must be closely associated with the presence of malignant signet ring cells regardless of their percentages

The Cytotoxic Effect of Annona muricata Leaf Extract on Triple Negative Breast Cancer Cell Line

Annona muricata, also known as soursop, has been reported to show cytotoxic activities against cancer cell lines. In this study, we evaluated the antiproliferative effect of Annona muricata leaf extract on the triple negative breast cancer cell line (MDA-MB-231). The antiproliferative effects of leaf extracts on MDA-MB-231cell line were evaluated by means of cell proliferation assay with XTT Reagent (Biological Industries, Israel). The assay was a colorimetric test based on the reduction tetrazolium salt, XTT to colored formazan products by mitochondria of live cells. In brief, cells were seeded into 96-well microtiter plates (Greiner) at a concentration of 5.0 × 104 cells/well and incubated for 72 h in medium containing horizontal dilutions of leaf extract. In each plate, the assay was performed with a column of blank medium control and a cell control column. Then, XTT reagent was added and the soluble product was measured at 500 nm with Biotek Elisa Reader, 96-well plate reader. IC50 value was calculated 320 µg/mL on MDA-MB-231 cells. In conclusion, these results may suggest that Annona muricata is a promising candidate for metastatic breast cancer treatment