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1.
Brief Bioinform ; 24(1)2023 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-36464485

RESUMO

Due to the increasing importance of graphs and graph streams in data representation in today's era, concept drift detection in graph streaming scenarios is more important than ever. Contributions to concept drift detection in graph streams are minimal and practically non-existent in the field of toxicology. This paper applied the discriminative subgraph-based drift detector (DSDD) to graph streams generated from real-world toxicology datasets. We used four toxicology datasets, each of which yielded two graph streams - one with abrupt drift points and one with gradual drift points. We used DSDD both with the standard minimum description length (MDL) heuristic and after replacing MDL with a much simpler heuristic SIZE (number of vertices + number of edges), and applied it to all generated graph streams containing abrupt drift points and gradual drift points for varying window sizes. Following that, we compared and analyzed the results. Finally, we applied a long short-term memory based graph stream classification model to all the generated streams and compared the difference in the performances obtained with and without detecting drift using DSDD. We believe that the results and analysis presented in this paper will provide insight into the task of concept drift detection in the toxicology domain and aid in the application of DSDD in a variety of scenarios.

2.
Org Biomol Chem ; 20(5): 1103-1111, 2022 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-35029621

RESUMO

A palladium(II) complex [(κ4-{1,2-C6H4(NCH-C6H4O)2}Pd] (1) supported by a dianionic salen ligand [1,2-C6H4(NCH-C6H4O)2]2- (L) was synthesised and used as a molecular pre-catalyst in the hydroboration of aldehydes and ketones. The molecular structure of Pd(II) complex 1 was established by single-crystal X-ray diffraction analysis. Complex 1 was tested as a competent pre-catalyst in the hydroboration of aldehydes and ketones with pinacolborane (HBpin) to produce corresponding boronate esters in excellent yields at ambient temperature under solvent-free conditions. Further, the complex 1 proved to be a competent catalyst in the reductive amination of aldehydes with HBpin and primary amines under mild and solvent-free conditions to afford a high yield (up to 97%) of corresponding secondary amines. Both protocols provided high conversion, superior selectivity and broad substrate scope, from electron-withdrawing to electron-donating and heterocyclic substitutions. A computational study based on density functional theory (DFT) revealed a reaction mechanism for Pd-catalysed hydroboration of carbonyl species in the presence of HBpin. The protocols also uncovered the dual role of HBpin in achieving the hydroboration reaction.

3.
J Mol Struct ; 1261: 132869, 2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-35340531

RESUMO

The manuscript deals with cost-effective synthesis, structural characterization and in silico SARS-CoV-2 screening activity of 5-membered heterocycle-substituted benzimidazole derivatives, 1-((1H-pyrrol-2-yl)methyl)-2-(1H-pyrrol-2-yl)-1H-benzo[d]imidazole (L1), 2-(furan-2-yl)-1-(furan-2-ylmethyl)-1H-benzo[d]imidazole (L2), 2-(thiophen-2-yl)-1-(thiophen-2-ylmethyl)-1H-benzo[d]imidazole (L3). The benzimidazole compounds were synthesized through a green-synthetic approach by coupling of 5-membered heterocyclic-carboxaldehyde and o-phenylenediamine in water under an aerobic condition. The compounds were characterized by various spectroscopic methods and X-ray structural analysis. The suitable single-crystals of the methyl derivative of L3 were grown as L3' which crystallized in a monoclinic system and the thiophene groups co-existed in a nearly a perpendicular orientation. Further, in silico anti-SARS-CoV-2 proficiency of the synthetic derivatives is evaluated against main protease (Mpro) and non-structural proteins (nsp2 and nsp7) of SARS-CoV-2. Molecular docking and molecular dynamics analysis of the ligands (L1-L3) against Mpro and nsp2 and nsp7 for 50 ns reveal that L3 turns out to be the superlative antiviral candidate against Mpro, nsp2 and nsp7 of SARS-CoV-2 as evident from the binding score and stability of the ligand-docked complexes with considerable binding energy changes.

4.
J Chem Phys ; 152(7): 075102, 2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-32087625

RESUMO

Multiple molecular logic gates were harvested on a single synthesized material, (E)-2-(2-hydroxy-3-methoxybenzylideneamino)phenol (MBAP), by combining excitation wavelength dependent multi-channel fluorescence outputs and the same chemical inputs. Interestingly, the effortless switching of logic behavior was achieved by simply tweaking the excitation wavelength and sometimes the emission wavelengths with no alteration of chemical inputs and the main device molecule, MBAP. Additionally, new generation purely optically driven memory units were designed on the same system supporting an almost infinite number of write-erase cycles since inter-conversion of memory states was completely free from chemical interferences and impurity issues. Two-way memory functions ("erase-read-write-read" and "write-read-erase-read") worked simultaneously on the same system and could be accessed by simple optical switching between two excitation and emission wavelengths. Our optically switchable device might outperform traditional multifunctional logic gates and memory devices that generally employ chemical triggers to switch functionality and memory states. These optically switchable multifunctional molecular logic gates and memory systems might drive smart devices in the near future with high energy efficiency, extended life span, structural and functional simplicity, exclusive reversibility and enhanced data storage density.

5.
Anal Methods ; 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38979725

RESUMO

This work introduces a thought-provoking design to develop a water-soluble chemical probe, sodium 4-hydroxy-3-((E)-((E)-((2-hydroxynaphthalen-1yl)methylene)hydrazono)methyl) benzenesulfonate (SW2) and its analytical characterization for the efficient detection and monitoring of Cu2+ ions in a matrix of s-, d-, and f-metal ions in pure water. The water-stable molecular probe, SW2, in the presence of Cu2+ salts in pure water exhibits a fluorescence turn-off characteristic with a high detection limit, 3.8 µM, and irresistibly holds 4-cycle reversibility in the presence of sulphide ions without any significant loss of its chemosensing efficiency. Spectroscopic and computational studies ensure 1 : 1 complexation between SW2 and Cu2+ ions, leading to the formation of SW2-Cu2+ chelate, thus inducing dynamic quenching of SW2 emission, which subsequently reverts on the addition of S2- ions in water. Additionally, the SW2-Cu2+ chelate was isolated in microcrystalline powder and the complexation was studied with mass spectrometry and EPR analysis. Computational analysis reveals the remarkable reduction in the S0-S1 energy level of the SW2-Cu2+ complex, which is attributed to the drastic quenching of the fluorescence intensity. Furthermore, SW2 was successfully applied to the detection of Cu2+ ions in tap and pond water. Interestingly, the probe is also effective for the determination of Cu2+ ions in the aqueous solution of a Cu-based fungicide (copper oxychloride), commercially available as Blitox in India, thus evaluating the effectiveness of SW2 in real sample analysis.

6.
IEEE J Biomed Health Inform ; 28(3): 1240-1251, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37030702

RESUMO

Generative adversarial networks (GANs) have become popular in medical imaging because of their remarkable performance and ability to translate images across different domains. However, GANs face several issues in image-to-image translation, including training instability, lack of diversity, and mode collapse. These issues become even more complex when using cyclic GANs. Additionally, collecting paired images required for GANs may be costly, especially in the medical domain. Cyclic GANs are a favorable choice for addressing this issue, as they can convert cross-domain images. However, no pre-existing technique or algorithm is comprehensive enough to handle diverse datasets and applications. To address these issues, we propose a novel Quantized Evolutionary Gradient Aware Multiobjective Cyclic GAN (QEMCGAN) that employs evolutionary computation, multiobjective optimization, and an intelligent selection scheme. We use simulated annealing and Pareto ranking selection using three fitness criteria to address local optima stagnation. Additionally, we use model quantization because of its suitability for low-cost IoT-based applications. Extensive trials reveal that EMCGAN and QEMCGAN produces more visually realistic images than other approaches while preserving both background information and salient features. In addition, QEMCGAN performs on par with the baseline approach even when the model size is halved, making it more efficient.


Assuntos
Algoritmos , Exercício Físico , Humanos , Processamento de Imagem Assistida por Computador
7.
Anal Methods ; 16(7): 1058-1068, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38270504

RESUMO

An AIE-active pyrene-terpyridine derivative, (4'-(pyren-1-yl)-2,2':6',2''-terpyridine) (1) was found to form nanoaggregate in an aqueous medium. The probe involved hydrogen bonding with solvent molecules that modulated the charge transfer behavior and consequently resulted in different spectroscopic behavior due to the formation of fluorescent organic nanoparticles (FONs). In the presence of Cu2+ ions, FONs displayed a ratiometric red shift of the absorption band (360 to 420 nm) accompanied by a prominent naked-eye color change from colorless to light yellow. With a gradual increase in water content, 1 displayed a huge red shift of the emission band (430 to 475 nm) denoting its switching from monomer to FONs. In the presence of Cu2+, the 475 nm emission band of FONs gradually diminished, facilitating the micromolar scale detection of Cu2+ (LOD = 8.57 µM) in a 100% aqueous medium with a fluorogenic color change from cyan to dark. The SEM and DLS data indicated the cation-induced disaggregation of FONs, which was further confirmed by mass spectral analysis and electron paramagnetic resonance measurement. In addition, the high selectivity of FONs towards Cu2+ ions over other potential cations and the 2 : 1 (1-Cu2+) binding stoichiometry were also determined. Moreover, the spectroscopic behavior of the monomeric amphiphilic probe was well supported by extensive DFT study. Such detection of Cu2+ ions in pure aqueous medium denoting an aggregation-disaggregation event is very rare in the literature.

8.
Cureus ; 16(5): e60078, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38860085

RESUMO

BACKGROUND: Tibial plateau fractures pose a significant challenge to orthopedic surgeons due to their complex nature and potential for long-term morbidity. Surgical intervention is often necessary to restore anatomical alignment and optimize functional outcomes. This study aimed to evaluate the efficacy of minimally invasive percutaneous plate osteosynthesis (MIPPO) compared to open reduction and internal fixation (ORIF) in the management of tibial plateau fractures. MATERIALS AND METHODS: The present hospital-based observational study was conducted at Agartala Government Medical College for two years. Seventy adult patients with tibial plateau fractures were included, with surgical interventions performed based on fracture characteristics. Postoperative outcomes, including knee range of movements, functional recovery, and complication rates, were assessed at six months. RESULTS: MIPPO demonstrated superior outcomes compared to ORIF, with a higher proportion of participants achieving knee range of movements > 120 degrees (66.7% versus 36%; p = 0.030), excellent functional outcomes (66.7% versus 36%; p = 0.046), and lower postoperative complication rates (2.2% versus 28%; p = 0.001). Fracture union times were significantly shorter in MIPPO (12.49 weeks) when compared to ORIF (14 weeks) (p = 0.009). CONCLUSION: MIPPO offers advantages over conventional ORIF in terms of functional recovery and complication rates while demonstrating comparable fracture union times. These findings advocate for the adoption of MIPPO as a preferred surgical technique for tibial plateau fractures.

9.
J Biomol Struct Dyn ; 41(5): 1798-1810, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-35000553

RESUMO

The manuscript reports the green-chemical synthesis of a new diindole-substituted benzimidazole compound, B1 through a straightforward route in coupling between indolyl-3-carboxaldehyde and o-phenylenediamine in water medium under the aerobic condition at 75 ºC. The single crystal X-ray structural analysis of B1 suggests that the disubstituted benzimidazole compound crystallizes in a monoclinic system and the indole groups exist in a perpendicular fashion with respect to benzimidazole moiety. The SARS-CoV-2 screening activity has been studied against 1 × 10e4 VeroE6 cells in a dose-dependent manner following Hoechst 33342 and nucleocapsid staining activity with respect to remdesivir. The compound exhibits 92.4% cell viability for 30 h and 35.1% inhibition against VeroE6 cells at non-cytotoxic concentration. Molecular docking studies predict high binding propensities of B1 with the main protease (Mpro) and non-structural (nsp2 and nsp7-nsp8) proteins of SARS-CoV-2 through a number of non-covalent interactions. Molecular dynamics (MD) simulation analysis for 100 ns confirms the formation of stable conformations of B1-docked proteins with significant changes of binding energy, attributing the potential inhibition properties of the synthetic benzimidazole scaffold against SARS-CoV-2. Communicated by Ramaswamy H. Sarma.


Assuntos
COVID-19 , Humanos , Simulação de Acoplamento Molecular , SARS-CoV-2 , Benzimidazóis/farmacologia , Sobrevivência Celular , Simulação de Dinâmica Molecular , Inibidores de Proteases
10.
Dalton Trans ; 52(26): 8850-8856, 2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37338097

RESUMO

A structurally characterized porous Ag(I)-molecular cage AgMOC and a Cu(II)-coordination polymer CuCP with a pre-synthesized ligand 1,3-bis(((E)-2-methoxybenzylidene)amino)propan-2-ol and its parental amine with thiocyanate are reported to harness electrical mobility-driven hydrogen evolution activity. Porosity-induced electrically conductive AgMOC emerges as a better electrocatalyst with a Tafel slope of 104 mV per decade over Cu(II)-polymer's slope of 128 mV per decade. The electrochemical stability and durability of the designed electrocatalysts in harnessing the HER activity are also examined under experimental conditions.

11.
Dalton Trans ; 52(15): 4964-4972, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-36951181

RESUMO

The sustainable production of privileged amines by the catalytic reduction of nitriles with an inexpensive silane polymethylhydrosiloxane (PMHS) holds great promise to replace conventional synthetic routes that have limited applicability and involve the use of expensive metal catalysts. The use of late 3d-metal complexes provides an excellent platform for the rational design of inexpensive catalysts with exquisite control over their electronic and structural features through metal-ligand cooperativity. In this context, we have realistically designed two complexes based on nickel(II) and cobalt(II) with a redox-active imino-o-benzoquinonato ligand. The compounds were characterized by a suite of spectroscopic methods, cyclic voltammetry and single-crystal X-ray diffraction. Both complexes showed excellent catalytic activity in transforming various organonitriles into the corresponding primary amines selectively using the inexpensive PMHS. The catalytic performance of the complexes was evaluated by various control experiments and spectroscopic studies with detailed computational calculations revealing the crucial role of the non-innocent imino-o-benzoquinonato ligand and metal(II) ion cooperativity in controlling the reactivity and selectivity of the key metal-hydride intermediates in the course of catalytic reduction.

12.
Carbohydr Polym ; 291: 119614, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35698411

RESUMO

We report the solvent-free green synthesis of two Schiff bases, (E)-2-((2-hydroxy-3-methoxybenzylidene)amino)-4-methylphenol (SL1) and (E)-2-((2-hydroxybenzylidene) amino)-4-methylphenol (SL2), and their inclusion complexes with ß-cyclodextrin (ß-CD). The encapsulation phenomenon, structural characteristics and hydrolytic stabilities of the SL1, SL2 and their inclusion complexes are determined with a suite of spectroscopic, analytical and crystallographic analyses. Dose and time-dependent cytotoxicity study of SL1-ß-CD and SL2-ß-CD against two breast cancer cell lines, Michigan Cancer Foundation-7 (MCF-7) and metastatic mammary adenocarcinoma1 (MDA-MB-231), exhibit excellent inhibitory activity with significant non-cytotoxic concentrations and ensure a multifold elevation of bio-potency than the parent Schiff base compounds. The Annexin-V assay determines the efficacy of these inclusion complexes to trigger apoptosis, suggesting that SL2-ß-CD possesses better efficacy as an anti-cancer drug. To the best of our knowledge, we, for the first time, report the inclusion of nanocrystalline Schiff bases into ß-CD for multifold enrichment of bio-potency.


Assuntos
Antineoplásicos , beta-Ciclodextrinas , Antineoplásicos/química , Apoptose , Humanos , Células MCF-7 , Bases de Schiff/química , beta-Ciclodextrinas/farmacologia
13.
J Phys Chem Lett ; 13(46): 10759-10766, 2022 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-36374525

RESUMO

Herein we report the fabrication of green emitting hybrid lead bromide perovskite single crystals (HLBPSCs), their anion exchange mediated tunable yellow luminescence and thereby their coupling ability with blue emitting inorganic complex leading to generation of a photostable white light emission, with properties close to bright day sunlight. The partial anion exchange reaction to green emitting HLBPSCs led to formation of yellow emitting anion exchanged HLBPSCs─which are termed as AE-HLBPSCs herein. Then, AE-HLBPSCs were chemically combined with blue emitting Zn-aspirin complex to produce white light with a photoluminescence quantum yield (PLQY) of 47.7%. The solid form of the white light emitting (WLE) composite (followed by coating with poly methyl methacrylate─PMMA) showed color coordinates of (0.34, 0.33), color rendering index of 76 and correlated color temperature of 5282 K. Furthermore, the PMMA coated inorganic complex coupled AE-HLBPSCs showed the preservation of their WLE nature and luminescence stability in their solid form.

14.
Dalton Trans ; 51(4): 1561-1570, 2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-34989731

RESUMO

The advent of d-d type complex salts for designing smart functional materials with versatile utility inspired us to develop a novel type of M(II)-Ce(IV) complex salts [M(II) = Cu and Zn ions]. In this study, we present for the first time a holistic approach to design and prepare metal complex salts of the novel hybrid d-f block type, [Cu(bpy)2]2[Ce(NO3)6]2 (1), [Cu(phen)2(NO3)]2[Ce(NO3)6](HNO3) (2), [Zn(bpy)2(NO3)][ClO4] (3), and [Zn(phen)2(NO3)]2 [Ce(NO3)6] (4); [bpy = 2,2'-bipyridine; phen = 1,10-phenanthroline]. The intrinsic structural and morphological properties of the compounds have been revealed by employing a suite of analytical and spectroscopic methods. X-ray structural analysis reveals that the copper(II) centres in the cationic complex units of 1 and 2 adopt a highly distorted tetrahedral and a rare bicapped square pyramidal coordination geometry, respectively. The zinc(II) ions in both 3 and 4 adopt the rare bicapped square pyramidal geometry while the cerium(IV) ions in 1, 2 and 4 exist in a dodecahedral geometry. Investigation of supramolecular interactions reveals that intermolecular O⋯H and O⋯π short contacts bind the complex units in 1, while predominant π⋯π interactions, along with O⋯H and O⋯π short contacts, produce the binding force among the complex units in 2. We further employed the complex salts (1-4) to construct Schottky devices to reveal the role of these new complex salts in the charge-transport phenomenon. The carrier mobilities (µ) for salts 1-4 were determined to be 1.76 × 10-6, 9.02 × 10-6, 1.86 × 10-8, and 4.31 × 10-8 m2 V-1 s-1, with respective transit times (τ) of 439, 85, 4.17 × 103, and 1.79 × 103 ns, which suggest that complex salt 2 is the best candidate with the highest transport properties among all the complex salts. A crystal engineering perspective sheds light on the charge-transport properties of the complex salts, emphasizing the attribution of the best performance of 2 to its predominant π⋯π interactions. The synthesis of this new type of complex salts, their physicochemical properties and their charge-transport applications envisage great promise for the development of novel crystalline materials with smart functionalities.

15.
Sci Rep ; 11(1): 23122, 2021 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-34848758

RESUMO

Phenazine scaffolds are the versatile secondary metabolites of bacterial origin. It functions in the biological control of plant pathogens and contributes to the producing strains ecological fitness and pathogenicity. In the light of the excellent therapeutic properties of phenazine, we have synthesized a hydrated 2,3-diaminophenazinium chloride (DAPH+Cl-·3H2O) through direct catalytic oxidation of o-phenylenediamine with an iron(III) complex, [Fe(1,10-phenanthroline)2Cl2]NO3 in ethanol under aerobic condition. The crystal structure, molecular complexity and supramolecular aspects of DAPH+Cl- were confirmed and elucidated with different spectroscopic methods and single crystal X-ray structural analysis. Crystal engineering study on DAPH+Cl- exhibits a fascinating formation of (H2O)2…Cl-…(H2O) cluster and energy framework analysis of defines the role of chloride ions in the stabilization of DAPH+Cl-. The bactericidal efficiency of the compound has been testified against few clinical bacteria like Streptococcus pneumoniae, Escherichia coli, K. pneumoniae using the disc diffusion method and the results of high inhibition zone suggest its excellent antibacterial properties. The phenazinium chloride exhibits a significant percentage of cell viability and a considerable inhibition property against SARS-CoV-2 at non-cytotoxic concentration compared to remdesivir. Molecular docking studies estimate a good binding propensity of DAPH+Cl- with non-structural proteins (nsp2 and nsp7-nsp-8) and the main protease (Mpro) of SARS-CoV-2. The molecular dynamics simulation studies attribute the conformationally stable structures of the DAPH+Cl- bound Mpro and nsp2, nsp7-nsp8 complexes as evident from the considerable binding energy values, - 19.2 ± 0.3, - 25.7 ± 0.1, and - 24.5 ± 0.7 kcal/mol, respectively.


Assuntos
Simulação de Acoplamento Molecular , SARS-CoV-2 , Simulação de Dinâmica Molecular
16.
Heliyon ; 6(9): e04953, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33005785

RESUMO

Focusing on the huge importance associated in developing functional materials, this research study describes the synthesis, characterization of morphology, bactericidal activity and cytotoxic effect of iron oxide nanoparticles (IONPs). IONPs have been successfully fabricated through thermal decomposition of a diiron(III) complex precursor. The morphology of the nanoparticle has been delineated with different spectroscopic and analytic methods. Scanning and transmission electron microscopy (FE-SEM and HR-TEM) analyses estimate the cross linked porous structure of IONPs with an average size ~97 nm. Dynamic light scattering (DLS) study of IONPs determines the hydrodynamic diameter as 104 nm. The cytotoxic behavior of IONPs has been examined against human lung cancer cell line (A549) through different fluorescence staining studies which ensure the mode of apoptosis for cell death of A549. Furthermore, measurement of reactive oxygen species suggests the destruction of mitochondrial membrane of Staphylococcus aureus, leading to effective bactericidal propensity which holds a good promise for IONPs to become a clinically approved antibacterial agent.

17.
Dalton Trans ; 47(20): 7059-7069, 2018 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-29744514

RESUMO

Unusual self-sorting of an ion-pair under highly crowded conditions driven by a synthesized intelligent molecule 2-((E)-(3-((E)-2-hydroxy-3-methoxybenzylideneamino)-2-hydroxypropyl imino)methyl)-6-methoxyphenol, hereafter HBP, is described. When a mixture of various metal salts was allowed to react with HBP, only a specific ion-pair ZnII/AcO- in the solution simultaneously reacted, resulting in high-fidelity ion-pair recognition of HBP. This phenomenon was evidenced by significant changes in the absorption spectra and huge enhancement in emission intensity of HBP. The property that one molecule preferring one particular cation-anion pair over others is a rare but interesting phenomenon. Thus, the potential to interact selectively with the targeted ion-pair resulting in the formation of a specific complex recognized HBP as a new class of molecule that might find future applications in real time and on-site monitoring and separation of new molecules.

18.
Microbiol Res ; 207: 116-133, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29458846

RESUMO

In the present study, 134 morphologically distinct actinobacteria isolates were obtained from soil samples from 10 different localities in the Saudi Arabian desert. The preliminary screening revealed that 16 of these isolates possessed antimicrobial activity. One isolate, which was identified as Streptomyces sp. DA3-7, possessed broad-spectrum antimicrobial activity against both gram-positive and gram-negative bacteria, as well as against fungi, and modified nutrient glucose medium was suitable for Streptomyces sp. DA3-7 to produce extracellular metabolites. The ethyl acetate extract of Streptomyces sp. DA3-7 exhibited antimicrobial activity against Enterococcus faecalis and Salmonella typhimurium, with minimum inhibitory concentrations of 78 and 156µg/mL, respectively, as well as strong cytotoxicity (24h IC50 85µg/mL) against MCF-7 human breast adenocarcinoma cells. The active compound was separated, purified, and identified as Pyridine-2,5-diacetamide (C9H11N3O2+H+, 194.21), which possessed a lowest minimum inhibitory concentration (31.25µg/mL) against both Escherichia coli and Cryptococcus neoformans. The antimicrobial activities of this novel compound are reported here for the first time.


Assuntos
Alcaloides/farmacologia , Anti-Infecciosos/farmacologia , Antineoplásicos/farmacologia , Piridinas/farmacologia , Streptomyces/metabolismo , Adenocarcinoma/tratamento farmacológico , Alcaloides/química , Anti-Infecciosos/química , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Cryptococcus neoformans/efeitos dos fármacos , Cryptococcus neoformans/crescimento & desenvolvimento , Clima Desértico , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/crescimento & desenvolvimento , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Feminino , Humanos , Células MCF-7 , Testes de Sensibilidade Microbiana , Piridinas/química , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/crescimento & desenvolvimento , Arábia Saudita , Microbiologia do Solo , Streptomyces/genética , Streptomyces/isolamento & purificação
19.
Technol Health Care ; 25(3): 577-589, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28035940

RESUMO

This paper deals with the investigation of external joint movement with respect to leg kinematics. The overall leg kinematics were investigated by means of a rigid, three-segment, 3D leg model. A 3D kinematics and ground reaction forces was being restructured. The images were then authenticated with the help of a cadaveric investigation and analysis. This was eventually used for prediction of the overall leg kinematics. Thereafter FEM based simulations were undertaken, and muscle forces were investigated based on the data available. With the help of FEM predictions it was found and understood that the overall leg kinematics were having higher loading factor with respect to the lateral.


Assuntos
Fenômenos Biomecânicos/fisiologia , Perna (Membro)/fisiologia , Humanos , Perna (Membro)/anatomia & histologia , Modelos Anatômicos , Movimento/fisiologia , Músculo Esquelético/fisiologia , Pressão
20.
Spectrochim Acta A Mol Biomol Spectrosc ; 144: 148-54, 2015 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-25754390

RESUMO

A new trinuclear zinc(II) complex, [Zn3(L)(NCS)2](NO3)2·CH3OH·H2O (1), of a (N,O)-donor compartmental Schiff base ligand (H2L=N,N'-bis(3-methoxysalicylidene)-1,3-diamino-2-propanol), has been synthesized in crystalline phase. The zinc(II) complex has been characterized by elemental analysis, IR spectroscopy, UV-Vis spectroscopy, powder X-ray diffraction study (PXRD), (1)H NMR, EI mass spectrometry and thermogravimetric analysis. PXRD revealed that 1 crystallizes in P-1 space group with a=9.218 Å, b=10.849 Å, c=18.339 Å, with unit cell volume is 2179.713(Å)(3). Fluorescence spectra in methanolic solution reflect that intensity of emission for 1 is much higher compared to H2L and both the compounds exhibit good fluorescence properties. The complex 1 exhibits significant catalytic activities of biological relevance, viz. catechol oxidase. In methanol, it efficiently catalyzes the oxidation of 3,5-di-tert-butylcatechol (3,5-DTBC) to corresponding quinone via formation of a dinuclear species as [Zn2(L)(3,5-DTBC)]. Electron Paramagnetic Resonance (EPR) experiment suggests generation of radicals in the presence of 3,5-DTBC and it may be proposed that the radical pathway is probably responsible for conversion of 3,5-DTBC to 3,5-DTBQ promoted by complex of redox-innocent Zn(II) ion.


Assuntos
Catecol Oxidase/metabolismo , Complexos de Coordenação/química , Complexos de Coordenação/síntese química , Luminescência , Modelos Moleculares , Zinco/metabolismo , Catecóis/química , Catecóis/metabolismo , Complexos de Coordenação/metabolismo , Espectroscopia de Ressonância de Spin Eletrônica , Cinética , Ligantes , Oxirredução , Pós , Soluções , Solventes , Espectrometria de Fluorescência , Termogravimetria , Difração de Raios X
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