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  1. Usman F, Dennis JO, Meriaudeau F, Ahmed AY, Seong KC, Fen YW, et al.
    Molecules, 2020 Sep 25;25(19).
    PMID: 32992942 DOI: 10.3390/molecules25194414
    The optical constants of Para-Toluene sulfonic acid-doped polyaniline (PANI), PANIchitosan composites, PANI-reduced graphene-oxide composites and a ternary composite comprising of PANI, chitosan and reduced graphene-oxide dispersed in diluted p-toluene sulfonic acid (PTSA) solution and N-Methyl-2-Pyrrolidone (NMP) solvent have been evaluated and compared. The optical constant values were extracted from the absorbance spectra of thin layers of the respective samples. The potential utilization of the materials as the active sensing materials of surface plasmon resonance biosensors has also been assessed in terms of the estimated value of the penetration depth through a dielectric medium. The results show a reasonable dependence of the optical constant parameters on the solvent type. Higher real part refractive index (n) and real part complex dielectric permittivity (ε') values were observed for the samples prepared using PTSA solution, while higher optical conductivity values were observed for the NMP-based samples due to their relatively higher imaginary part refractive index (k) and imaginary part complex dielectric permittivity (ε″) values. In addition, NMP-based samples show improvement in terms of the penetration depth through a dielectric medium by around 9.5, 1.6, 4.4 and 2.9 times compared to PTSA-based samples for the PANI, PANI-chitosan, PANI-RGO and the ternary composites, respectively. Based on these, it is concluded that preparation of these materials using different dispersion solvents could produce materials of different optical properties. Thus, the variation of the dispersion solvent will allow the flexible utilization of the PANI and the composites for diverse applications.
    Matched MeSH terms: Pyrrolidinones/chemistry*
  2. Amir Sidek, Rashidah Arsat, He X, Kalantar-zadeh K, Wlodarski W
    Sains Malaysiana, 2013;42:213-217.
    Poly-vinyl-pyrrolidone (PVP)/polyaniline based surface acoustic wave (SAW) sensors were fabricated and characterized and their performances towards hydrogen gas were investigated. The PVP/polyaniline fibers composite were prepared by electrospinning of the composite aqueous solution deposited directly onto the active area of SAW transducers. Via scanning electron microscopy (SEM), the morphology of the deposited nanostructure material was observed. From the dynamic response, frequency shifts of 6.243 kHz (1% H2) and 8.051 kHz (1% H2) were recorded for the sensors deposited with PVP/ES and PVP/EB, respectively.
    Matched MeSH terms: Pyrrolidinones
  3. Knowlton ED, Kamath A
    Neotrop. Entomol., 2018 Dec;47(6):780-785.
    PMID: 30191403 DOI: 10.1007/s13744-018-0631-6
    Many organisms use chemicals to deter enemies. Some spiders can modify the composition of their silk to deter predators from climbing onto their webs. The Malaysian golden orb-weaver Nephila antipodiana (Walckenaer) produces silk containing an alkaloid (2-pyrrolidinone) that functions as a defense against ant invasion-ants avoid silk containing this chemical. In the present study, we test the generality of ants' silk avoidance behavior in the field. We introduced three ant species to the orb webs of Nephila clavipes (Linnaeus) in the tropical rainforest of La Selva, Costa Rica. We found that predatory army ants (Eciton burchellii Westwood) as well as non-predatory leaf-cutting ants (Atta cephalotes Linnaeus and Acromyrmex volcanus Wheeler) avoided adult N. clavipes silk, suggesting that an additional species within genus Nephila may possess ant-deterring silk. Our field assay also suggests that silk avoidance behavior is found in multiple ant species.
    Matched MeSH terms: Pyrrolidinones/chemistry*
  4. Sheshala R, Hong GC, Yee WP, Meka VS, Thakur RRS
    Drug Deliv Transl Res, 2019 04;9(2):534-542.
    PMID: 29484530 DOI: 10.1007/s13346-018-0491-y
    The objectives of this study were to develop biodegradable poly-lactic-co-glycolic acid (PLGA) based injectable phase inversion in situ forming system for sustained delivery of triamcinolone acetonide (TA) and to conduct physicochemical characterisation including in vitro drug release of the prepared formulations. TA (at 0.5%, 1% and 2.5% w/w loading) was dissolved in N-methyl-2-pyrrolidone (NMP) solvent and then incorporated 30% w/w PLGA (50/50 and 75/25) polymer to prepare homogenous injectable solution. The formulations were evaluated for rheological behaviour using rheometer, syringeability by texture analyser, water uptake and rate of implant formation by optical coherence tomography (OCT) microscope. Phase inversion in situ forming formulations were injected into PBS pH 7.3 to form an implant and release samples were collected and analysed for drug content using a HPLC method. All formulations exhibited good syringeability and rheological properties (viscosity: 0.19-3.06 Pa.s) by showing shear thinning behaviour which enable them to remain as free-flowing solution for ease administration. The results from OCT microscope demonstrated that thickness of the implants were increased with the increase in time and the rate of implant formation indicated the fast phase inversion. The drug release from implants was sustained over a period of 42 days. The research findings demonstrated that PLGA/NMP-based phase inversion in situ forming implants can improve compliance in patient's suffering from ocular diseases by sustaining the drug release for a prolonged period of time and thereby reducing the frequency of ocular injections.
    Matched MeSH terms: Pyrrolidinones/chemistry*
  5. Faidzal, O., Azmi, M.N., Kalavathi, R.
    MyJurnal
    Squamous cell carcinoma of the rectum is a very rare malignancy. In the literature, the incidence has been reported as 0.25 to 0.1 per 10000 colorectal carcinomas. Due to its rarity, the treatment and behavior of this tumor have only been discussed in case reports. As a result, several theories regarding their pathogenesis have been proposed. We will describe our experience in managing this rare malignancy in a 69-year-old man who presented with altered bowel habit. Surgery remains the mainstay of treatment. Issues regarding additional treatment have been presented in the literature. The rarity of this tumour also raises issues regarding criteria for diagnosis which we will try to highlight and discuss.
    Matched MeSH terms: Pyrrolidinones
  6. Niestanak, S. Abedi, Faieza, A.A., Sulaiman, S., Rosnah, M.Y.
    MyJurnal
    This study of the implementation of enterprise resource planning (ERP) in a customer driven environment analyzes the critical success factors throughout the initialization phase. The dynamic and stochastic nature of customer driven environments results in a massive workload of product structure configuration tasks related to new arrivals on one hand and a constant updating process on the other. Meanwhile, the development and implementation of an ERP system was studied from the very first step (i.e. the feasibly study for implementing an ERP) to the last step (i.e. testing the outputs of the implemented system) in an office furniture company for three years. The study involved analyzing of the data collected that were from a series of interviews, as well as direct observations and reviewing of the company’s documents. Based on the output of the analysis phase, a top-down hierarchical analysis of goals and CSFs were carried out according to the CSF analysis method. Three top level objectives included reducing project failure risk, project cost, and project time. Analysing the primary results of the study (i.e. activity model, data flow diagram DFD of different levels, system problems and potential solutions descriptions, etc.) revealed that the critical phase of the implementation project would be product structure initialization and this should be taken into consideration as the bottleneck of production planning in customer driven environment, which dramatically reduced the ERP efficiency in this kind of environment. Moreover, initializing issues of the same process is the main obstacle to the success of the ERP implementation, as it considerably raises the project failure risk and cost. Therefore, the simplification, facilitation, and automation of the PSCM process, which lead to acceleration of this process, are the most significant success factors for the ERP implementation projects in customer driven environment.
    Matched MeSH terms: Pyrrolidinones
  7. Johari SA, Mohtar M, Syed Mohamad SA, Mohammat MF, Sahdan R, Mohamed A, et al.
    Biomed Res Int, 2017;2017:8032865.
    PMID: 28536702 DOI: 10.1155/2017/8032865
    Previously we have discovered a synthetically derived pyrrolidone alkaloid, MFM501, exhibiting good inhibitory activity against 53 MRSA and MSSA isolates with low cytotoxicity against three normal cell-lines with IC50 values at >625 µg/ml. Time-kill assay, scanning electron microscopy (SEM) analysis, in vivo oral acute toxicity test, and mice peritonitis model were carried out in this study. In the time-kill study, MFM501 showed a less than 3 log10 decrease in bacterial colony concentration value (CFU/ml) which represented a bacteriostatic action while displaying a time-dependent inhibitory mechanism. Following that, SEM analysis suggested that MFM501 may exert its inhibitory activity via cytoplasmic membrane disruption. Moreover, MFM501 showed no toxicity effect on treated mice at an estimated median acute lethal dose (LD50) value of more than 300 mg/kg and less than 2000 mg/kg. For the efficacy test, a mean effective dose (ED50) of 87.16 mg/kg was obtained via a single dose oral administration. Our data demonstrated that MFM501 has the potential to be developed further as a new, safe, and effective oral-delivered antibacterial agent against MRSA isolates.
    Matched MeSH terms: Pyrrolidinones/administration & dosage*; Pyrrolidinones/pharmacology*; Pyrrolidinones/toxicity
  8. Yamamoto T, Tsunematsu Y, Hara K, Suzuki T, Kishimoto S, Kawagishi H, et al.
    Angew Chem Int Ed Engl, 2016 05 17;55(21):6207-10.
    PMID: 27072782 DOI: 10.1002/anie.201600940
    Geometric isomerization can expand the scope of biological activities of natural products. The observed chemical diversity among the pseurotin-type fungal secondary metabolites is in part generated by a trans to cis isomerization of an olefin. In vitro characterizations of pseurotin biosynthetic enzymes revealed that the glutathione S-transferase PsoE requires participation of the bifunctional C-methyltransferase/epoxidase PsoF to complete the trans to cis isomerization of the pathway intermediate presynerazol. The crystal structure of the PsoE/glutathione/presynerazol complex indicated stereospecific glutathione-presynerazol conjugate formation is the principal function of PsoE. Moreover, PsoF was identified to have an additional, unexpected oxidative isomerase activity, thus making it a trifunctional enzyme which is key to the complexity generation in pseurotin biosynthesis. Through the study, we identified a novel mechanism of accomplishing a seemingly simple trans to cis isomerization reaction.
    Matched MeSH terms: Pyrrolidinones
  9. Lim KH, Raja VJ, Bradshaw TD, Lim SH, Low YY, Kam TS
    J Nat Prod, 2015 May 22;78(5):1129-38.
    PMID: 25919190 DOI: 10.1021/acs.jnatprod.5b00117
    Six new indole alkaloids, viz., cononusine (1, a rare example of an iboga-pyrrolidone conjugate), ervaluteine (2), vincamajicine (3), tacamonidine (4), 6-oxoibogaine (5), and N(4)-chloromethylnorfluorocurarine chloride (6), and two new vobasinyl-iboga bisindole alkaloids, ervatensines A (7) and B (8), in addition to other known alkaloids, were isolated from the stem-bark extract of the Malayan Tabernaemontana corymbosa. The structures of these alkaloids were established on the basis of NMR and MS analyses and, in one instance (7), confirmed by X-ray diffraction analysis. Vincamajicine (3) showed appreciable activity in reversing multidrug resistance in vincristine-resistant KB cells (IC50 2.62 μM), while ervatensines A (7) and B (8) and two other known bisindoles displayed pronounced in vitro growth inhibitory activity against human KB cells (IC50 < 2 μM). Compounds 7 and 8 also showed good growth inhibitory activity against A549, MCF-7, MDA-468, HCT-116, and HT-29 cells (IC50 0.70-4.19 μM). Cell cycle and annexin V-FITC apoptosis assays indicated that compounds 7 and 8 inhibited proliferation of HCT-116 and MDA-468 cells, evoking apoptotic and necrotic cell death.
    Matched MeSH terms: Pyrrolidinones/isolation & purification*; Pyrrolidinones/pharmacology*; Pyrrolidinones/chemistry
  10. Gharibshahi E, Saion E, Johnston RL, Ashraf A
    Appl Radiat Isot, 2019 May;147:204-210.
    PMID: 30953937 DOI: 10.1016/j.apradiso.2019.02.015
    Platinum nanoparticles were synthesized using the gamma radiolytic technique in an aqueous solution containing Platinum tetraammine chloride in presence of poly vinyl pyrrolidone, isopropanol, tetrahydrofuran and deionized water. The gamma irradiation was carried out in a60Co gamma source chamber and the particle size was found to decrease from 4.88 to 3.14 nm on increasing the gamma radiation dose from 80 to 120 kGy. UV-visible absorption spectra were measured and revealed two steady absorption maxima at 216 and 264 nm in the UV region, which was blue shifted (i.e. toward lower wavelength) with decreasing particle size. By taking the conduction electrons of an isolated particle that are not entirely free, but instead bound to their respective quantum levels, the optical absorption of platinum nanoparticles can be calculated via intra-band quantum excitation for particle sizes similar to those measured experimentally. We found that the calculated absorption maxima of electronic excitations matched the measured absorption maxima well. This finding suggests that the optical absorption of metal nanoparticles commonly applied in nanoscience and nanotechnology can be described accurately by the quantum excitation of conduction electrons.
    Matched MeSH terms: Pyrrolidinones
  11. Sutirman ZA, Sanagi MM, Abd Karim J, Abu Naim A, Wan Ibrahim WA
    Int J Biol Macromol, 2018 Feb;107(Pt A):891-897.
    PMID: 28935540 DOI: 10.1016/j.ijbiomac.2017.09.061
    Crosslinked chitosan beads were grafted with N-vinyl-2-pyrrolidone (NVP) using ammonium persulfate (APS) as free radical initiator. Important variables on graft copolymerization such as temperature, reaction time, concentration of initiator and concentration of monomer were optimized. The results revealed optimum conditions for maximum grafting of NVP on 1g crosslinked chitosan as follows: reaction temperature, 60°C; reaction time, 2h and concentrations of APS and NVP of 2.63×10-1M and 26.99×10-1M, respectively. The modified chitosan beads were characterized by FTIR spectroscopy, 13C NMR, SEM and BET to provide evidence of successful crosslinking and grafting reactions. The resulting material (cts(x)-g-PNVP) was evaluated as adsorbent for the removal of Cu(II) ions from aqueous solutions in a batch experiment. The Langmuir and Freundlich adsorption models were also applied to describe the equilibrium isotherms. The results showed that the adsorption of the copper ions onto the beads agreed well with Langmuir model with the maximum capacity (qmax) of 122mgg-1.
    Matched MeSH terms: Pyrrolidinones/chemistry
  12. Hassan M, Baig AA, Attique SA, Abbas S, Khan F, Zahid S, et al.
    Daru, 2021 Jun;29(1):73-84.
    PMID: 33537864 DOI: 10.1007/s40199-020-00384-3
    PURPOSE: To predict potential inhibitors of alpha-enolase to reduce plasminogen binding of Streptococcus pneumoniae (S. pneumoniae) that may lead as an orally active drug. S. pneumoniae remains dominant in causing invasive diseases. Fibrinolytic pathway is a critical factor of S. pneumoniae to invade and progression of disease in the host body. Besides the low mass on the cell surface, alpha-enolase possesses significant plasminogen binding among all exposed proteins.

    METHODS: In-silico based drug designing approach was implemented for evaluating potential inhibitors against alpha-enolase based on their binding affinities, energy score and pharmacokinetics. Lipinski's rule of five (LRo5) and Egan's (Brain Or IntestinaL EstimateD) BOILED-Egg methods were executed to predict the best ligand for biological systems.

    RESULTS: Molecular docking analysis revealed, Sodium (1,5-dihydroxy-2-oxopyrrolidin-3-yl)-hydroxy-dioxidophosphanium (SF-2312) as a promising inhibitor that fabricates finest attractive charges and conventional hydrogen bonds with S. pneumoniae alpha-enolase. Moreover, the pharmacokinetics of SF-2312 predict it as a therapeutic inhibitor for clinical trials. Like SF-2312, phosphono-acetohydroxamate (PhAH) also constructed adequate interactions at the active site of alpha-enolase, but it predicted less favourable than SF-2312 based on binding affinity.

    CONCLUSION: Briefly, SF-2312 and PhAH ligands could inhibit the role of alpha-enolase to restrain plasminogen binding, invasion and progression of S. pneumoniae. As per our investigation and analysis, SF-2312 is the most potent naturally existing inhibitor of S. pneumoniae alpha-enolase in current time.

    Matched MeSH terms: Pyrrolidinones/pharmacokinetics; Pyrrolidinones/chemistry
  13. Basri M, Samsudin S, Ahmad MB, Razak CN, Salleh AB
    Appl Biochem Biotechnol, 1999 Sep;81(3):205-17.
    PMID: 15304777
    Lipase from Candida rugosa was immobilized by entrapment on poly(N-vinyl- 2-pyrrolidone-co-2-hydroxyethyl methacrylate) (poly[VP-co-HEMA]) hydrogel, and divinylbenzene was the crosslinking agent. The immobilized enzymes were used in the esterification reaction of oleic acid and butanol in hexane. The activities of the immobilized enzymes and the leaching ability of the enzyme from the support with respect to the different compositions of the hydrogels were investigated. The thermal, solvent, and storage stability of the immobilized lipases was also determined. Increasing the percentage of composition of VP from 0 to 90, which corresponds to the increase in the hydrophilicity of the hydrogels, increased the activity of the immobilized enzyme. Lipase immobilized on VP(%):HEMA(%) 90:10 exhibited the highest activity. Lipase immobilized on VP(%):HEMA(%) 50:50 showed the highest thermal, solvent, storage, and operational stability compared to lipase immobilized on other compositions of hydrogels as well as the native lipase.
    Matched MeSH terms: Pyrrolidinones
  14. Ahmad AL, Sugumaran J, Shoparwe NF
    Membranes (Basel), 2018 Dec 14;8(4).
    PMID: 30558199 DOI: 10.3390/membranes8040131
    In this study, the antifouling properties of polyethersulfone (PES) membranes blended with different amounts of ZnO nanoparticles and a fixed ratio of N-methyl-2-pyrrolidone (NMP)-acetone mixture as a solvent were investigated. The properties and performance of the fabricated membranes were examined in terms of hydrophilicity, porosity, pore size, surface and cross-section image using scanning electron microscopy (SEM), surface roughness using atomic force microscopy (AFM), pure water flux, and humic acid filtration. Addition of ZnO as expected was found to improve the hydrophilicity as well as to encourage pore formation. However, the agglomeration of ZnO at a higher concentration cannot be avoided even when dissolved in a mixed solvent. The presence of highly volatile acetone contributed to the tight skin layer of the membrane which shows remarkable antifouling ability with the highest flux recovery ratio and negligible irreversible fouling. ZnO NPs in acetone/NMP mixed solvent shows an improvement in flux and rejection, but, the fouling resistance was moderate compared to the pristine membrane.
    Matched MeSH terms: Pyrrolidinones
  15. Mashitah, M.D., Masitah, H., Ramachandran, K.B.
    MyJurnal
    Streptococcus zooepidemicus (SZ) is an aerotolerant bacteria and its ability to survive under reactive oxidant raises the question of the existence of a defense system against oxidative stress. As a characteristic of lactic acid bacteria, Streptococcus lacks an ordinary anti-oxidative stress enzyme, catalases and an electron transport chain. Whether this bacterium resists oxidative stress prior to an exposure to a higher level of an oxidizing agent H2O2 in hyaluronic acid fermentation is not known. This paper describes that Streptococcus cells, once treated with lower concentrations of H2O2 (i.e. 0.25, 0.50 and 1.0 mM) at least, were prepared for a subsequent higher concentrations of H2O2 such as 20.5 and 100 mM. At low concentrations (i.e. 0.25, 0.50 and 1.0 mM), H2O2 was found to act as a stimulant for HA synthesis, but it became toxic if presented at a very high level (100 mM H2O2). The highest HA yield to glucose consumed (YHAtotal/glu) was 0.017 gg-1 for the cells pre-treated with 0 mM of H2O2, and then exposed to 20.5 mM H2O2. Thus, this implied that this bacteria might possess a defense mechanism against oxidative stress and that this system was inducible.
    Matched MeSH terms: Pyrrolidinones
  16. Yamamoto T, Tsunematsu Y, Noguchi H, Hotta K, Watanabe K
    Org. Lett., 2015 Oct 16;17(20):4992-5.
    PMID: 26414728 DOI: 10.1021/acs.orglett.5b02435
    Successful activation of the pyranonigrin biosynthetic gene cluster and gene knockout in Aspergillus niger plus in vivo and in vitro assays led to isolation of six new products, including a spiro cyclobutane-containing dimeric compound, which served as the basis for the proposed comprehensive pyranonigrin biosynthetic pathway. Two redox enzymes are key to forming the characteristic fused γ-pyrone core, and a protease homologue performs the exo-methylene formation.
    Matched MeSH terms: Pyrrolidinones/chemistry*
  17. Stock I
    Med Monatsschr Pharm, 2014 Jan;37(1):4-10; quiz 11-2.
    PMID: 24490433
    Hand, foot and mouth disease (HFMD) is a highly contagious, world-wide distributed viral illness that affects predominantly children. It is caused by several enteroviruses, such as coxsackieviruses A6, A10, A16 and enterovirus 71. In most cases, HFMD follows a benign and self-limiting course. After an incubation period of 3 to 10 days, fever and sore throat, the first symptoms of the disease, appear. A few days later, maculopapular or vesicular eruptions form on the palms and soles as well as in the oral cavity. Since the year 2000, several large HFMD outbreaks have been reported in many Asian regions such as China, Malaysia and Vietnam. In some of these outbreaks, high incidences of severe progressive HFMD forms with some fatalities were observed. Such diseases have been caused primarily by enterovirus 71 strains and were characterized frequently by sudden onset of fever, encephalitis/meningitis and severe respiratory symptoms such as pulmonary edema. Further severe neurological and cardiac complications have also been observed during these outbreaks. Recently, some HFMD outbreaks caused by the coxsackievirus A6 have been reported in several parts of the world. These illnesses also affected adults and were characterized by more severe symptoms of "classical" HFMD. In addition, outbreaks of coxsackievirus-A6-associated HFMD in many countries were associated with onychomadesis, with the loss of nails occurring up to two months after initial symptoms. Treatment of "classical" HFMD is usually symptomatic, a generally recommended antiviral therapy does not exist. In severe HFMD cases, suitable treatment also encompasses mechanical ventilation, as well as the additional application of antiviral agents such as ribavirin. In the last years, several novel agents with good in vitro and in vivo activity against enteroviruses have been developed. A vaccine against HFMD is not yet available.
    Matched MeSH terms: Pyrrolidinones/therapeutic use
  18. Martin A, Moore C, Mallon PW, Hoy J, Emery S, Belloso W, et al.
    AIDS, 2013 Sep 24;27(15):2403-11.
    PMID: 23921615 DOI: 10.1097/01.aids.0000432534.47217.b4
    To compare changes over 48 weeks in bone mineral density (BMD) between participants randomized to lopinavir/ritonavir (LPV/r) + raltegravir (RAL) or LPV/r + 2-3 nucleoside/nucleotide reverse transcriptase inhibitors (N(t)RTIs) as second line therapy.
    Matched MeSH terms: Pyrrolidinones/adverse effects
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