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1.
PeerJ Comput Sci ; 8: e789, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35111906

RESUMEN

A large range of applications have been identified based upon the communication of underground sensors deeply buried in the soil. The classical electromagnetic wave (EM) approach, which works well for terrestrial communication in air medium, when applied for this underground communication, suffers from significant challenges attributing to signal absorption by rocks, soil, or water contents, highly varying channel condition caused by soil characteristics, and requirement of big antennas. As a strong alternative of EM, various magnetic induction (MI) techniques have been introduced. These techniques basically depend upon the magnetic induction between two coupled coils associated with transceiver sensor nodes. This paper elaborates on three basic MI communication mechanisms i.e. direct MI transmission, MI waveguide transmission, and 3D coil MI communication with detailed discussion of their working mechanism, advantages and limitations. The comparative analysis of these MI techniques with each other as well as with EM wave method will facilitate the users in choosing the best method to offer enhanced transmission range (upto 250 m), reduced path loss (<100 dB), channel reliability, working bandwidth (1-2 kHz), & omni-directional coverage to realize the promising MI-based wireless underground sensor network (WUSN) applications.

2.
Vet World ; 14(5): 1258-1262, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-34220128

RESUMEN

Gainful livestock farming requires selective breeding of animals with certain heritable desirable traits which gives profitability in terms of farm produce. Modern dairy animals are selected for traits which directly or indirectly contribute to high milk production. The concept of "feed conversion efficiency" in terms of milk production is now vigorously taken up by researchers and farm managers for recognizing and breeding efficient milk-producing animals. The whole concept of economic farming thus requires identification of "elite" animals, meeting above criteria as base population for the farm enterprise. Farmers and animal traders have been selecting best animals based on certain physical characters, which were also accepted by the breeding scientists as phenotypes. Data mining allows uncovering of hidden patterns in the data for better understanding of data relationship for developing suitable models for further improvements. Along with artificial intelligence techniques, data mining has opened new avenues for achieving high resource utilization efficiency and sustainable profitability in livestock production systems. The present review discusses and summarizes various data mining techniques and decision support systems for scientific dairy farming.

3.
Molecules ; 25(10)2020 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-32443652

RESUMEN

Previously synthesized novel chalcone oxime ethers (COEs) were evaluated for inhibitory activities against monoamine oxidases (MAOs) and acetylcholinesterase (AChE). Twenty-two of the 24 COEs synthesized, except COE-17 and COE-24, had potent and/or significant selective inhibitory effects on MAO-B. COE-6 potently inhibited MAO-B with an IC50 value of 0.018 µM, which was 105, 2.3, and 1.1 times more potent than clorgyline, lazabemide, and pargyline (reference drugs), respectively. COE-7, and COE-22 were also active against MAO-B, both had an IC50 value of 0.028 µM, which was 67 and 1.5 times lower than those of clorgyline and lazabemide, respectively. Most of the COEs exhibited weak inhibitory effects on MAO-A and AChE. COE-13 most potently inhibited MAO-A (IC50 = 0.88 µM) and also significantly inhibited MAO-B (IC50 = 0.13 µM), and it could be considered as a potential nonselective MAO inhibitor. COE-19 and COE-22 inhibited AChE with IC50 values of 5.35 and 4.39 µM, respectively. The selectivity index (SI) of COE-22 for MAO-B was higher than that of COE-6 (SI = 778.6 vs. 222.2), but the IC50 value (0.028 µM) was slightly lower than that of COE-6 (0.018 µM). In reversibility experiments, inhibitions of MAO-B by COE-6 and COE-22 were recovered to the levels of reference reversible inhibitors and both competitively inhibited MAO-B, with Ki values of 0.0075 and 0.010 µM, respectively. Our results show that COE-6 and COE-22 are potent, selective MAO-B inhibitors, and COE-22 is a candidate of dual-targeting molecule for MAO-B and AChE.


Asunto(s)
Chalcona/química , Inhibidores de la Colinesterasa/química , Inhibidores de la Monoaminooxidasa/química , Oximas/química , Acetilcolinesterasa/química , Acetilcolinesterasa/efectos de los fármacos , Chalcona/farmacología , Inhibidores de la Colinesterasa/aislamiento & purificación , Inhibidores de la Colinesterasa/farmacología , Éteres/química , Éteres/farmacología , Humanos , Cinética , Monoaminooxidasa/química , Monoaminooxidasa/efectos de los fármacos , Inhibidores de la Monoaminooxidasa/aislamiento & purificación , Inhibidores de la Monoaminooxidasa/farmacología , Oximas/farmacología
4.
CNS Neurol Disord Drug Targets ; 18(8): 643-654, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31550216

RESUMEN

BACKGROUND: Chalcones are considered as the selective scaffold for the inhibition of MAO-B. OBJECTIVES: A previously synthesized ethyl acetohydroxamate-chalcones (L1-L22) were studied for their inhibitory activities against human recombinant monoamine oxidase A and B (hMAO-A and hMAO-B, respectively) and acetylcholinesterase (AChE) as multi-target directed ligands for the treatment of Alzheimer's Disease (AD). METHODS: Enzyme inhibition studies of MAO-A, MAO-B and AChE is carried out. Computational studies such as Molecular docking, Molecular Mechanics/Generalized Born Surface Area calculations, ADMET prediction, and protein target prediction are also performed. RESULTS: Among the screened compounds, compound L3 has most potent hMAO-B inhibition with an IC50 value of 0.028 ± 0.0016 µM, and other compounds, L1, L2, L4, L8, L12, and L21 showed significant potent hMAO-B inhibition with IC50 values of 0.051 ± 0.0014, 0.086 ± 0.0035, 0.036 ± 0.0011, 0.096 ± 0.0061, 0.083 ± 0.0016, and 0.038 ± 0.0021 µM, respectively. On the other hand, among the tested compounds, compound L13 showed highest hMAO-A inhibition with an IC50 value of 0.51± 0.051 µM and L9 has a significant value of 1.85 ± 0.045 µM. However, the compounds L3 and L4 only showed high selectivities for hMAO-B with Selectivity Index (SI) values of 621.4 and 416.7, respectively. Among the substituents in ring A of ethyl acetohydroxamate-chalcones (L1-L9), F atom at p-position (L3) showed highest inhibitory effect against hMAO-B. This result supports the uniqness and bizarre behavior of fluorine. Moreover, chalcones L3, L4, L9, L11, and L12 showed potential AChE inhibitory effect with IC50 values of 0.67, 0.85, 0.39, 0.30, and 0.45 µM, respectively. Inhibitions of hMAO-B by L3 or L4 were recovered to the level of the reversible reference (lazabemide), and were competitive with Ki values of 0.0030 ± 0.0002 and 0.0046 ± 0.0005 µM, respectively. Inhibitions of AChE by L3 and L11 were of the competitive and mixed types with Ki values of 0.30 ± 0.044 and 0.14 ± 0.0054 µM, respectively. CONCLUSION: The studies indicated that L3 and L4 are considered to be promising multitarget drug molecules with potent, selective, and reversible competitive inhibitors of hMAO-B and with highly potent AChE inhibitory effect.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Chalconas/uso terapéutico , Inhibidores de la Monoaminooxidasa/uso terapéutico , Acetilcolinesterasa/metabolismo , Enfermedad de Alzheimer/metabolismo , Diseño de Fármacos , Humanos , Simulación del Acoplamiento Molecular , Monoaminooxidasa/metabolismo , Relación Estructura-Actividad
5.
Bioorg Chem ; 86: 631-640, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30818235

RESUMEN

An efficient method for palladium-catalyzed CO cross-coupling of ethyl acetohydroxamate (EAcHO) with 4-bromo-chalcones has been developed to synthesize novel chalcones. The two supporting ligands, namely tBuXPhos (L7), and cataCXium®PIntB (L16) were found to be effective ligands towards the Pd-catalyzed CO cross-coupling reaction to afford the desired product in moderate to excellent yields (50-99%). The coupled products were screened for in vitro blood stage antiplasmodial activity against Plasmodium falciparum (3D7) using the [3H] hypoxanthine incorporation inhibition assay. Of the twenty two compounds screened, eleven showed good antiplasmodial activity with IC50 values ranging from 6-16 µg/mL. The selected active molecules 11, 16, 22, (IC50 12 µg/mL) and 19 (IC50 6 µg/mL) were studied for their cytotoxic effect against HepG2 Cells (human hepatocellular liver carcinoma cell lines), showing the selectivity index (SI) values are greater than 4 except chalcone 22. Our result demonstrates a methodology for synthesizing novel chalcones as a new class of antiplasmodial agent.


Asunto(s)
Antimaláricos/farmacología , Antineoplásicos/farmacología , Chalconas/farmacología , Ácidos Hidroxámicos/farmacología , Paladio/química , Plasmodium falciparum/efectos de los fármacos , Antimaláricos/síntesis química , Antimaláricos/química , Antineoplásicos/síntesis química , Antineoplásicos/química , Carbono/química , Catálisis , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Chalconas/síntesis química , Chalconas/química , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Células Hep G2 , Humanos , Ácidos Hidroxámicos/química , Estructura Molecular , Oxígeno/química , Pruebas de Sensibilidad Parasitaria , Relación Estructura-Actividad
6.
Molecules ; 23(5)2018 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-29757989

RESUMEN

A new class of compounds comprising two series of chalcones with 2,2,2-trifluoroethoxy group and 2-fluoroethoxy groups were synthesized and screened for in vitro antiplasmodial activity against Plasmodium falciparum (3D7) using the [³H] hypoxanthine incorporation inhibition assay. Chalcones with 2,2,2-trifluoroethoxy groups substituted on the p- and m-positions of the 1-phenyl ring showed weak antiplasmodial activity, while compounds substituted on the o-position of the 1-phenyl ring displayed enhanced antiplasmodial activity, thus indicating that 2,2,2-trifluoroethoxy groups on the 1-phenyl ring of chalcones show position-dependent antiplasmodial activity. Of the 34 compounds synthesized, chalcones 3a and 3f exhibited significant inhibitory effects, with IC50 values of 3.0 µg/mL and 2.2 µg/mL, respectively. Moreover, these compounds 3a and 3f showed profound antiplasmodial activity in combination with artemisinin in vitro. The most active molecules, 3a, and 3f, were further assessed for their cytotoxicity towards mammalian Vero cells and the selectivity index (SI) values are 8.6, and 8.2 respectively, being considered non-toxic. We also studied the antiplasmodial activity of 2-fluoroethoxychalcones to discern the effect of the number of fluorine atoms in the fluoroethoxy group. Our results showed that chalcones with 2-fluoroethoxy group on the 1-phenyl ring exhibited more enhanced inhibitory effects on the growth of parasites than their trifluoro analogues, which reveals that monofluoroethoxy group is generally more effective than trifluoroethoxy group in the inhibition of parasite growth. Thus o-2,2,2-trifluoroethoxychalcones (Series 3) and 2-fluoroethoxychalcones may serve as good antiplasmodial candidates for future further development.


Asunto(s)
Antimaláricos/síntesis química , Antimaláricos/farmacología , Chalconas/síntesis química , Chalconas/farmacología , Plasmodium falciparum/efectos de los fármacos , Animales , Antimaláricos/química , Chalconas/química , Técnicas de Química Sintética , Chlorocebus aethiops , Eritrocitos/efectos de los fármacos , Eritrocitos/parasitología , Concentración 50 Inhibidora , Malaria Falciparum/tratamiento farmacológico , Malaria Falciparum/parasitología , Pruebas de Sensibilidad Parasitaria , Células Vero
7.
Chemistry ; 20(44): 14218-25, 2014 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-25236851

RESUMEN

We report an unprecedented BrettPhos ligand supported Pd-catalyzed CO bond-forming reaction of activated aryl halides with primary fluoroalkyl alcohols. We demonstrate that the Phosphine ligand (BrettPhos) possesses the property of altering the mechanistic pathway of reductive elimination from nucleophile to nucleophile. The Pd/BrettPhos catalyst system facilitates the reductive elimination of the oxygen nucleophile through an electronic pathway.

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