A Study on Aging Kinetics,Inhibition, and Reactivation of Organophosphate Compounds with Quails and Chicks Carboxylesterase

Organophosphate inhibits carboxylesterase thus regular treatment includes carboxylesterase oxime reactivator in combination with anti-muscarinic agents. In order to progress the understanding of species differences and to enable an additional reliable extrapolation of animal result to quail a study was initiated to inspect the effect of insecticide compounds, that is, mevinphos, ethoprop, and fenthion, with quail-serum carboxylesterase and common chicken-carboxylesterase. The rate constants for the inhibition of carboxylesterase by these organophosphate and for the aging and spontaneous reactivation of organophosphate-inhibited carboxylesterase enzyme as well as for the oxime-induced reactivation of organophosphate-inhibited carboxylesterase enzyme by the oximes trimedoxime, methoxime, N,N′-(ethano)bis(4-hydroxyiminomethyl)pyridinium methanosulphonate, HI-6, and HLö-7 were determined in this study. Compared to quail-serum carboxylesterase and chick-carboxylesterase displayed a lower sensitivity toward the inspected organophosphate. Furthermore, a slower aging and spontaneous reactivation of quail-serum carboxylesterase enzyme was recorded. The potency of the detected oxime reactivator was remarkably lower with organophosphate-inhibited quail-serum carboxylesterase.     

Biodegradation of Tetracycline Under Various Conditions and Effects on Microbial Community

Five hundred tons of antibiotics are consumed yearly in the world. In this study, the biodegradation characteristics of tetracycline (TET) under nitrate-reducing, sulfate-reducing, and methanogenic conditions were determined by batch tests. Also, effects of TET on mixed microbial cultures were revealed by microbiological analysis. In this scope, gas generation and composition, dissolved organic carbon, and electron acceptor concentrations were monitored during 120 days. Additionally, changes on quantities of specific microbial groups were determined by Q-PCR. TET showed non-biodegradable behavior under nitrate- and sulfate-reducing conditions, whereas slightly biodegradable behavior under methanogenic conditions approximately 46 % degradation. The effects of TET on the abundance of mixed culture varied according to taxonomic units. Sulfate-reducing bacteria were inhibited by TET, while archaeal, bacterial, and methanogenic populations were not affected significantly.     

Tualang Honey: A Decade of Neurological Research

Tualang honey has been shown to protect against neurodegeneration, leading to improved memory/learning as well as mood. In addition, studies have also demonstrated its anti-inflammatory and antioxidant properties. However, a substantial part of this research lacks systematization, and there seems to be a tendency to start anew with every study. This review presents a decade of research on Tualang honey with a particular interest in the underlying mechanisms related to its effects on the central nervous system. A total of 28 original articles published between 2011 and 2020 addressing the central nervous system (CNS) effects of Tualang honey were analysed. We identified five main categories, namely nootropic, antinociceptive, stress-relieving, antidepressant, and anxiolytic effects of Tualang honey, and proposed the underlying mechanisms. The findings from this review may potentially be beneficial towards developing new therapeutic roles for Tualang honey and help in determining how best to benefit from this brain supplement.     

Evaluation of infection imaging potential of <Superscript>131</Superscript>I-labeled imidazolium salt

Effective antimicrobial compounds are necessary due to increased resistance of antibiotics against microorganisms causing infectious diseases. In this study, imidazolium-TFSI salt [ITFSI: octyl-bis(3-methylimidazolium)-di(bis(trifluoromethane)sulfonimide)] was labeled with ¹³¹I with high efficiency. In vitro uptake experiments of ¹³¹I-ITFSI showed high uptake in gram-positive Staphylococcus aureus bacteria. ¹³¹I-ITFSI was also evaluated for comparison between bacterial infection and sterile inflammation by in vivo studies. The biodistribution results revealed that ¹³¹I-ITFSI might be used as a nuclear imaging agent for detection of bacterial infection.     

Cellulose nanocrystals from bleached rice straw pulp: acidic deep eutectic solvent versus sulphuric acid hydrolyses

The present work aims to investigate the feasibility of oxalic acid-choline chloride deep eutectic solvent (OA-ChCl DES), which serves as a promising green solvent that utilized in the acidic deep eutectic solvent (DES) hydrolysis. Oxalic acid-choline chloride DES cellulose nanocrystal (OA-ChCl DES CNC) was isolated from the bleached DES treated pulp (BP) through the acidic DES hydrolysis using 1:1 molar ratio of OA-ChCl DES. The functional groups, crystallinity index, morphological structure, particle size, zeta potential, thermal stability and surface chemistry of the OA-ChCl DES CNC were compared with the sulphuric acid cellulose nanocrystal (SA-CNC) that prepared via sulphuric acid hydrolysis. The findings revealed the presence of negatively charged carboxyl groups on OA-ChCl DES CNC surface after the acidic DES hydrolysis. The physicochemical analyses verified that the OA-ChCl DES CNC was in nano-sized range with polydispersity index (PdI) of 0.56, indicating slightly monodispersed nanoparticles. A stable OA-ChCl DES CNC colloidal suspension with zeta potential value of ?52.1?±?5.2 mV was obtained. The OA-ChCl DES CNC outweighed the SA-CNC in term of thermal stability (288 °C) despite having a slightly lower crystallinity index (76.7%). In fact, the OA-ChCl DES CNC with a yield of 55.1% was achieved through the acidic DES hydrolysis, suggesting that the OA-ChCl DES was capable of promoting efficient cleavage of strong hydrogen bonds in BP.

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A CNDO and INDO calculation of nuclear spin-spin coupling constants in HF,HF 2 − and H2F 3 −

Two semiempirically SCF methods are used to calculate nuclear spin-spin coupling constants in hydrogen bonded systems. Hydrogen bonding is found to influence strongly the spin-spin coupling constants and this can give valuable informations about changes in electron densities with hydrogen bonding.     

The effect of demineralization and torrefaction consequential pre-treatment on energy characteristic of palm empty fruit bunches

Journal of Thermal Analysis and Calorimetry - The refined pitch (1#) and impregnating pitch (2#) were obtained under certain conditions with the modified pitch as the raw materials. The data of...     

Synthesis and characterization of ZnO thin films by thermal evaporation

ZnO thin films have been successfully synthesized by thermal evaporation of pure zinc at 900 °C under the flow of different percentages of argon and oxygen gases. The films were characterized by X-ray diffraction (XRD), variable pressure scanning electron microscopy (VPSEM), energy dispersive X-ray spectroscopy (EDS) and UV–vis spectroscopy. The aim of this paper is to study the influence of the oxygen percentage on the structural and morphological properties of the ZnO films. VPSEM results show that very thick needle structures were produced at high oxygen percentages. EDS results revealed that only Zn and O are present in the sample, indicating a composition of pure ZnO. XRD results showed that the ZnO synthesized under different quantities of oxygen were crystalline with the hexagonal wurtzite structure. UV–vis spectroscopy results indicated that the optical band gap energies from the transmission spectrum are between 3.62 and 3.69 eV for ZnO thin films.     

Application of Stripping Voltammetry to the Determination of Guanethidine

Summary.  Adsorptive stripping voltammetry for the determination of guanethidine is employed. The drug is adsorbed onto the hanging mercury drop electrode, and the reduction current of the accumulated drug is measured by scanning the potential in the cathodic direction. The adsorption and redox behaviour are explored by cyclic voltammetry. Optimum experimental conditions include preconcentration potential, solution pH, potential scan rate, and preconcentration time. A detection limit of guanethidine of 0.992 ng/cm³ was obtained. Corresponding author. E-mail: ensafa@yahoo.com Received March 29, 2002; accepted April 12, 2002