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Objective: The electrochemical dissolution method of instrument retrieval emphasizes on the dissolution of the instrument rather than sacrificing dentine. Most of the studies conducted for electrochemical dissolution used fluoride-containing electrolytes and were performed inside a beaker. In this study, we used chloride-based fluids as electrolytes. Materials and Methods: Fifty extracted mandibular first premolars were divided into five groups based on the electrolytes used. Canals were enlarged to ProTaper Universal F2, and files were intentionally broken inside the canal. These specimens were subjected to electrochemical characterization by applying the potential of 9V for 20 min. Optical images were taken to assess the change in surface topography. The results were analyzed statistically by one-way analysis of variance (analysis of variance [ANOVA]). Results: The rate of dissolution based on the electrolyte used decreased in the following order, viz. Tyrode's solution>artificial saliva>normal saline>Ringer's lactate/physiological serum. Conclusion: Apart from fluoride, chloride-based electrolytes could be an efficient alternative.

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BACKGROUND AND AIMS: Kayser-Fleischer (KF) rings are due to copper deposition in Descemet membrane of the cornea in Wilson disease. Pseudo-KF ring (PKF), seen in patients with high bilirubin, is often misinterpreted as KF rings. These are bilirubin deposits in posterior corneal stroma. The aim of the study was to prospectively evaluate the presence of KF and PKF rings in Wilson disease and non-Wilsonian liver disease with serum bilirubin >5 mg/dL. METHODS: All patients referred from the hepatology unit with serum bilirubin >5 mg/dL were assessed by slit-lamp examination (SLE) and anterior segment optical coherence tomography at baseline, 3 months, and 6 months for differences in corneal deposits between KF and PKF rings. All other clinical, laboratory, radiological, genetic, and tissue diagnoses by liver biopsy were done as required to confirm the cause of liver disease. RESULTS: Among the 750 patients examined, corneal deposits were present in 13%, KF rings as granular deposits in 31.7%, and PKF as a posterior stromal hue in 68.3% of cases. PKF rings showed regression in 60%, disappearance in 36.6% at 3 months, and in 100% of cases at 6 months. KF ring showed regression in 10.7% and 8.3% until 6 months. Anterior segment optical coherence tomography identified KF ring as a hyperintense line on Descemet membrane in an additional 9.7% of patients compared with a scattered hyperintense hue in PKF rings. CONCLUSIONS: The presence of PKF rings in patients with jaundice is not uncommon and should be differentiated from true KF rings. Serial monitoring is essential to look for resolution, and anterior segment optical coherence tomography may be additionally helpful.

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Zingiberaceae plants are well known for their use in ethnomedicine. Curcuma mutabilis Skornick., M. Sabu & Prasanthk., is an endemic Zingiberaceae species from Western Ghats of Kerala, India. Here, we report for the first time, the anticancer potential of petroleum ether extract from C. mutabilis rhizome (CMRP) and a novel labdane diterpenoid, (E)-14, 15-epoxylabda-8(17), 12-dien-16-al (Cm epoxide) isolated from it. CMRP was found to be a mixture of potent bioactive compounds including Cm epoxide. Both the extract and the compound displayed superior antiproliferative activity against several human cancer cell lines, without any display of cytotoxicity towards normal human cells such as peripheral blood derived lymphocytes and erythrocytes. CMRP treatment resulted in phosphatidylserine externalization, increase in the levels of intracellular ROS, Ca2+, loss of mitochondrial membrane potential as well as fragmentation of genomic DNA. Analyses of transcript profiling and immunostained western blots of extract-treated cancer cells confirmed induction of apoptosis by both intrinsic and extrinsic pathways. The purified compound, Cm epoxide, was also found to induce apoptosis in many human cancer cell types tested. Both CMRP and the Cm epoxide were found to be pharmacologically safe in terms of acute toxicity assessment using Swiss albino mice model. Further, molecular docking interactions of Cm epoxide with selected proteins involved in cell survival and death were also indicative of its druggability. Overall, our findings reveal that the endemic C. mutabilis rhizome extract and the compound Cm epoxide isolated from it are potential candidates for development of future cancer chemotherapeutics.

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Hydro-distilled essential oils, from fresh rhizomes and leaves of Curcuma mutabilis Skornick., M.Sabu & Prasanthk., characterized by GC-MS revealed the presence of thirty three and twenty three compounds therein respectively. Whilst estrone methyl ether (3-Methoxyestra-1,3,5(10)-trien-17-one) was the major component in rhizome oil (47.35%), sesquiterpene hydrocarbons predominated as the major group (63.92%) in leaf oil with a higher preponderance of ß-caryophyllene (25.48%), ß-farnesene (19.47%) and α-humulene (11.01%). Weak antioxidant activities observed in these oils determined by DPPH and ABTS methods were apparently influenced both by the oil composition and the assay conditions. Rhizome oil showed higher antiproliferative activity than leaf oil against leukemic K562 (IC50-6.8µg/mL) and colorectal HCT116 (IC50-8.5µg/mL) cancer cell lines. This first report reveals composition and biological activities of essential oils from C. mutabilis.

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Plants have proved to be an important source of anti-cancer drugs. Wrightia arborea, an Indian Ayurvedic medicinal plant, is used traditionally to treat a variety of ailments. This study evaluates the antiproliferative/apoptotic potential of Wrightia arborea leaf extracts, prepared in different organic solvents, on cancer cell lines. MTT assay, light and fluorescence microscopy, flow cytometry, DNA laddering, alkaline comet assay, and western blotting were some of the techniques used for evaluation. Combinations of camptothecin, either with CHK1 inhibitor-PD407824 or with W. arborea leaf extract, were deployed to determine the G2 abrogating potential of the extract. The chloroform extract (WAC) selectively killed K562 cells, without affecting cancerous MCF-7, Hep G2 cells, and normal human peripheral blood lymphocytes. Cell death was characterized by observation of apoptotic bodies, increased Ca2+ and ROS, phosphatidyl serine externalization, mitochondrial membrane depolarization, DNA laddering, increased sub-G1 population, and altered expression of caspase 3, -9, and PARP. WAC also induced DNA damage, alterations in key G2/M phase protein expression, cell cycle perturbation, and potent G2 abrogation. The present study showed that W. arborea leaf extract, WAC, is capable of selectively killing leukemic cancer cells leaving normal lymphocytes unaffected. Our results indicate that this is effectuated through DNA damage and G2 abrogation leading to mitochondrial apoptosis. Taken together, this report contributes toward a better understanding of the anticancer properties of this traditional medicinal plant extract possessing valuable bioactive constituents which can serve as a bioresource for promising complimentary/alternative/chemopreventive therapeutics.

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An easy synthetic protocol for the peptide randomization of 3,5-dicyano pyridine derivatives by linking the pyridine core with a coumarin chromophore spaced by a linker triazole via copper (I) catalyzed [3+2] azide-alkyne cycloaddition (CuAAC) is described. The new peptidomimetics thus obtained are extended rule of 5 (eRo5) molecules suitable for the development of therapeutic agents for undruggable targets. The structural and photophysical properties of the molecules are also promising for the development of potential bio imaging agents based on these molecules.

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A nanosensor with fluorometric readout based on L-cysteine capped cadmium sulphide quantum dots for discriminative detection and determination of Brilliant blue FCF (BB) (in 0.5 M Tris buffer solution of pH 9.5) over other synthetic food colourants is developed. Mechanism of the nanosensor is based on inner filter effect (IFE). The addition of BB into quantum dot solution might induce the quenching of fluorescence. The nanosensor described in this report reveals its simplicity and flexibility due to less laborious and more cost-effective synthesis. The developed fluorescence sensor showed excellent selectivity towards BB, and allows the detection as low as 3.50 × 10-7 M. The developed sensor exhibited a linear concentration range of 4.00 × 10-5 to 4.50 × 10-6 M. More importantly, the proposed sensor exhibit sensitive responses toward BB in food samples such as sports drink and candies, demonstrating its potential in food analysis, which might be significant in food quality control in the future.

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We introduce a non-covalent pore engineering approach to achieve exceptional reversibility of functionalization in SBA-15 through viologen-pyranine charge transfer (CT) modules. By employing alkyl derivatives of pyranine as donors, we could exploit the strong CT interactions between pyranine and viologen to reversibly modify the pore size and philicity. The fast binding of the donors enables quick and facile functionalization within minutes at room temperature. The modularity of the approach enables modification of pores with custom-designed compositions, components, and functions. The high selectivity exhibited by viologen on the pore wall facilitated its use in a CT affinity column.

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Fluorescent PET (Photoinduced Electron Transfer) has been of particular growth in recent times. A novel PET based fluorescent sensor using unmodified CdSe quantum dots (QDs) has been developed for the trace determination of Nimesulide (NIM). The sensor is based on the selective fluorescence quenching of quantum dots by NIM in presence of other NSAIDs and is found that intensity of quenching is linearly related to NIM concentration in the range 8.2 × 10(-7) - 4.01 × 10(-5) M. The mechanism of interaction is discussed. Finally, the potential application of the proposed method for the trace determination of NIM in pharmaceutical formulation is demonstrated.

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A 3D porous Zn(II) metal-organic framework {[Zn(2)(H(2)dht)(dht)(0.5)(azpy)(0.5)(H(2)O)]·4H(2)O} (1; H(2)dht=dihydroxyterphthalate, azpy=4,4'-azobipyridine) has been synthesised by employing 2,5-dihydroxyterephthalic acid (H(4)dht), a multidentate ligand and 4,4'-azobipyridine by solvent-diffusion techniques at room temperature. The as-synthesised framework furnishes two different types of channels: one calyx-shaped along the [001] direction and another rectangle-shaped along the [101] direction occupied by guest water molecules. The dehydrated framework, {[Zn(2)(H(2)dht)(dht)(0.5)(azpy)(0.5)]} (1') provides 52.7% void volume to the total unit-cell volume. The pore surfaces of 1' are decorated with unsaturated Zn(II) sites and pendant hydroxyl groups of H(2)dht linker, thereby resulting in a highly polar pore surface. The dehydrated framework 1' shows highly selective adsorption of CO(2) over other gases, such as N(2), H(2), O(2) and Ar, at 195 K. Photoluminescence studies revealed that compound 1 exhibits green emission (λ(max)≈530 nm) on the basis of the excited-state intramolecular proton-transfer (ESIPT) process of the H(2)dht linker; no emission was observed in dehydrated solid 1'. Such guest-induced on/off emission has been correlated to the structural transformation and concomitant breaking and reforming of the OH···OCO hydrogen-bonding interaction in the H(2)dht linker in 1'/1.

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Metal mediated in situ C-N coupling between 4,4'-azobipyridine and disodium-trans-glutaconate at room temperature has formed a new multifunctional linker Z-dhpe which subsequently self-assembles with Zn(II) or Cd(II) resulting in a chiral or an achiral metal-organic framework, respectively, depending on its different coordination modes.