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New cyanogenic and alkyl glycoside constituents from Phyllagathis rotundifolia

Ling SK, Tanaka T, Kouno I

J Nat Prod, 2002 Feb;65(2):131-5.
PMID: 11858743

Methanolic extracts of the leaves, stems, and roots of Phyllagathis rotundifolia collected in Malaysia yielded seven galloylated cyanogenic glucosides based on prunasin, with six of these being new compounds, prunasin 2',6'-di-O-gallate (3), prunasin 3',6'-di-O-gallate (4), prunasin 4',6'-di-O-gallate (5), prunasin 2',3',6'-tri-O-gallate (6), prunasin 3',4',6'-tri-O-gallate (7), and prunasin 2',3',4',6'-tetra-O-gallate (8). Also obtained was a new alkyl glycoside, oct-1-en-3-yl alpha-arabinofuranosyl-(1-->6)-beta-glucopyranoside (9). For compounds 3-8, the galloyl groups were individually linked to the sugar moieties via ester bonds. All new structures were established on the basis of NMR and MS spectroscopic studies. In addition, prunasin (1), gallic acid and its methyl ester, beta-glucogallin, 3,6-di-O-galloyl-D-glucose, 1,2,3,6-tetra-O-galloyl-beta-D-glucose, strictinin, 6-O-galloyl-2,3-O-(S)-hexahydroxydiphenoyl-D-glucose, praecoxin B, and pterocarinin C were isolated and identified. The isolation of 1 and its galloyl derivatives (3-8) from a Melastomataceous plant are described for the first time.

Matched MeSH terms: Nitriles/isolation & purification; Nitriles/chemistry
The influence of genetic polymorphisms on the efficacy and side effects of anastrozole in postmenopausal breast cancer patients

Abubakar MB, Wei K, Gan SH

Pharmacogenet Genomics, 2014 Dec;24(12):575-81.
PMID: 25203739 DOI: 10.1097/FPC.0000000000000092

Breast cancer is a common cause of cancer mortality among women. Several genetic factors have been implicated in its development. Current treatment guidelines for estrogen receptor-positive breast cancer recommend that anastrozole [or any of the other two aromatase inhibitors (letrozole and exemestane)] is used as an alternative to tamoxifen or following several years of tamoxifen treatment. Nevertheless, this approach is still associated with many challenges, ranging from the recurrence of breast cancer to considerable interindividual variability in the tolerability of anastrozole, which may cause adverse effects, such as musculoskeletal symptoms, and lead to the withdrawal of many patients from treatment. Variabilities in the genes encoding the drug target (aromatase) or its metabolizing enzymes (CYP3A and UGT1A) contribute toward the interindividual variability in anastrozole's pharmacokinetics and/or pharmacodynamics. This paper reviews the role of genetic polymorphisms of CYP19A1, CYP3A4, and UGT1A4 in the responses of female hormone receptor-positive postmenopausal breast cancer patients to anastrozole. Many reviews in the literature have suggested that the study of functional polymorphisms and investigation of relevant genetic markers may provide valuable information in predicting responses to anastrozole in terms of its therapeutic and adverse effects. Nevertheless, more studies are required before the knowledge of its pharmacogenomics can be applied to the individualization of treatment to ensure that patients receive the maximum benefits. Therefore, future analyses, including but not limited to genome-wide association studies, are encouraged to address some of the gray areas in the pharmacogenomics of anastrozole therapy in postmenopausal breast cancer cases; this will help in providing guidance for future pharmacogenomics protocols when anastrozole is utilized in patients' management.

Matched MeSH terms: Nitriles/adverse effects; Nitriles/pharmacokinetics*
Correlation of Serum Estradiol and Duration of Anastrazole Therapy with Treatment Related Adverse Effects Among Postmenopausal Breast Cancer Women: A Cross-sectional Study

Abubakar MB, Gan SH

Niger J Physiol Sci, 2017 Dec 30;32(2):219-225.
PMID: 29485645

Although anastrozole (Anas) plays a key role in the management of endocrine sensitive post-menopausal (PM) breast cancer (BC), there is much variability in its efficacy and tolerability. Anas-associated musculoskeletal symptoms (MS) and other adverse reactions, such as hot flashes (HF) and vaginal dryness/dyspareunia (VDD), are common and can affect the quality of life of BC patients, even sometimes leading to treatment withdrawal. The aim of this study was to determine the clinical and demographic factors associated with these adverse events. This is a cross-sectional study in estrogen receptor (ER) positive PM women (n = 92) with stages I to III BC receiving Anas. Multivariate analyses were performed to investigate the factors associated with Anas-induced adverse effects such as MS, HF and VDD. A serum estradiol concentration was undetectable (< 36.7 pmol/L) in 68.1% of patients but was detectable within a normal range (>36.7-88.1 pmol/L) in the other 31.9% of patients, and this group was found to have a lower odds of having at least one adverse effect (AE) compared to those with undetectable levels [adjusted odds ratio (AOR) 0.12, 95% confidence interval (CI) 0.02 to 0.64, p = 0.013]. Women with grades II and III tumors and a family history of BC had a higher odds of AE (grade II: AOR 12.22, CI 1.48 to 100.80, p = 0.020; grade III: AOR 12.95, CI 1.25 to 134.33, p = 0.032) and VDD (AOR 5.99, CI 1.30 to 27.52, p = 0.021), respectively. Patients who received Anas treatment for more than one year had a higher odds of VDD (one to three years: AOR 34.57, CI 3.86, 309.50, p = 0.002; more than 3 years: AOR 27.90, CI 2.21 to 351.84, p = 0.010). Advanced age also lowered the odds of HF (AOR 0.90, CI 0.83 to 1.00, p = 0.049). In conclusion, patients' hormonal environments and durations of Anas treatment may play a role in developing Anas-induced adverse effects.

Matched MeSH terms: Nitriles/adverse effects*; Nitriles/pharmacology
Fulltext Bioactive 2-(Methyldithio)Pyridine-3-Carbonitrile from Persian Shallot (Allium stipitatum Regel.) Exerts Broad-Spectrum Antimicrobial Activity

Karunanidhi A, Ghaznavi-Rad E, Jeevajothi Nathan J, Joseph N, Chigurupati S, Mohd Fauzi F, et al.

Molecules, 2019 Mar 13;24(6).
PMID: 30871159 DOI: 10.3390/molecules24061003

Antibiotic resistance is a problem that continues to challenge the healthcare sector, especially in clinically significant pathogens like methicillin-resistant Staphylococcus aureus (MRSA). Herein is described the isolation and structure elucidation of a bioactive compound from Allium stipitatum with antimicrobial activity. Crude Allium stipitatum dichloromethane extract (ASDE) was subjected to systematic purification by chromatographic procedures to afford various bioactive fractions. A fraction that exhibited anti-MRSA activity (4 µg·mL-1) was further characterized to determine the structure. The structure of the compound was elucidated as 2-(methyldithio)pyridine-3-carbonitrile (2-Medpy-3-CN). The 2-Medpy-3-CN compound, which was screened for antimicrobial activity, exhibited minimum inhibitory concentrations (MICs) in the range of 0.5 to >64 µg·mL-1 for tested bacterial species and 0.25 to 2 µg·mL-1 for Candida spp. Further studies are important to confirm the drug target and mechanism of action.

Matched MeSH terms: Nitriles/isolation & purification; Nitriles/chemistry
Usage of vildagliptin among patients with type 2 diabetes mellitus attending a public primary healthcare clinics in Kuala Selangor District, Selangor

Farhani S, Sulizah S, Siti Khalimah R, Jasrinjeet Kaur K, Nur Hidayah Z, Nur Athirah R, et al.

Med J Malaysia, 2024 Jan;79(1):68-73.
PMID: 38287760

INTRODUCTION: Studies showed that vildagliptin can lower HbA1c levels by 0.8%-1%. However, there is limited data looking at vildagliptin use among suburban populations. The efficacy of vildagliptin use may differ among different populations, especially those with low socio-economic status. Thus, this study aimed to assess the HbA1c reduction after vildagliptin initiation, treatment patterns and the reason for its initiation among patients with type 2 diabetes mellitus attending outpatient clinics in Kuala Selangor District, Selangor.
MATERIALS AND METHODS: This is a cross-sectional, retrospective study design. All patients who received vildagliptin in the Pharmacy Integrated Health System (PHIS) registry database from 2016 to 2021 were included as study samples. The exclusion criteria were being less than 18 years old and having type 1 diabetes mellitus. Patients' medical records were retrieved after sampling, and data were collected. One medical record was missing, thus SPSS analysis were performed on 144 vildagliptin users.
RESULTS: In total, 84 females (58.3%) and 60 males (41.7%) with a mean age of 62.1 (±10.1) years were analysed in this study. Mean HbA1c pre-therapy was 8.5 ± 2.1%; while posttherapy 6 months demonstrated a mean HbA1c of 7.9 ± 1.8%. Use of vildagliptin alone or as an adjunct was associated with a mean reduction of 0.6% in HbA1c (p = 0.01). Factors influencing this HbA1c reduction were advancing age, specifically individuals aged 62 years and older (p = 0.02), patients who are already receiving insulin therapy (p=0.00) and those who express a willingness to commence insulin treatment during the counselling session prior to initiating the treatment plan (p = 0.00). Reasons for vildagliptin initiation documented by prescribers were non-insulin acceptance (n = 59, 40.97%), frequent hypoglycaemia (n = 6, 4.1%) and non-compliance with medications (n = 23, 15.9%). There was no association between demographic, medical background and reason for starting vildagliptin variables and HbA1c reduction (p < 0.001).
CONCLUSION: This study showed that initiating vildagliptin alone or as an adjunct therapy significantly reduced HbA1c and is beneficial for uncontrolled diabetes patients. While advancing age, concurrent administration of insulin and the patients' willingness to accept insulin treatment prior to the commencement of therapy were the factors that influenced HbA1c reduction among patients receiving vildagliptin therapy, we recommend primary care providers prioritise all of the significant variables discovered before initiating vildagliptin for their patients.

Matched MeSH terms: Nitriles/adverse effects; Nitriles/therapeutic use
Fulltext Studies on the effect of lambdacyhalothrin on Anopheles maculatus Theobald and its response to residual spraying at Jeram Kedah, Negeri Sembilan, Malaysia

Vythilingam I, Chiang GL, Mahadevan S, Eng KL, Chan ST, Singh KI

Southeast Asian J. Trop. Med. Public Health, 1993 Mar;24(1):138-42.
PMID: 8362288

A field trial was carried out to study the effect of lambdacyhalothrin on Anopheles maculatus in trap huts in Jeram Kedah, Negeri Sembilan, Malaysia. Two trap huts were built, of which one was sprayed with lambdacyhalothrin at a dosage of 25 mg ai/m2 and the other served as control. Eight collectors commenced collecting mosquitos from 1900 to 2400 hours, two each indoors and outdoors. Bioassay was also carried out in the treated and control huts to determine susceptibility of adult mosquitos to lambdacyhalothrin. In the treated hut more mosquitos were present during the pre- spraying period. Lambdacyhalothrin gave a mortality of 100% against An. maculatus for 8 months.

Matched MeSH terms: Nitriles
Field evaluation of alphacypermethrin and lambda-cyhalothrin against Aedes aegypti and Aedes albopictus in Malaysia

Sulaiman S, Karim MA, Omar B, Omar S

J Am Mosq Control Assoc, 1995 Mar;11(1):54-8.
PMID: 7616191

Alphacypermethrin (Fendona) and lambda-cyhalothrin (Icon) were evaluated against sentinel bloodfed adults and 4th-instar larvae of Aedes aegypti in a housing estate in Malaysia. The impact of both pyrethroids on field populations of Ae. aegypti and Aedes albopictus were monitored weekly using oviposition trap samples. Both alphacypermethrin and lambda-cyhalothrin showed adulticidal and larvicidal effects.

Matched MeSH terms: Nitriles
A urea precursor to synthesize carbon nitride with mesoporosity for enhanced activity in the photocatalytic removal of phenol

Lee SC, Lintang HO, Yuliati L

Chem Asian J, 2012 Sep;7(9):2139-44.
PMID: 22733646 DOI: 10.1002/asia.201200383

A urea precursor was used for the first time to prepare mesoporous carbon nitride (MCN) by a thermal polymerization process with silica nanospheres as a hard template. Although the prepared MCN samples have similar structures and optical properties, it was revealed that the specific surface area, pore-size distribution, and morphology of the MCN samples depend on the initial mass ratio of urea to silica. Compared to the bulk carbon nitride (BCN) that only gave 20% phenol removal (6 h of irradiation), the activities can be enhanced up to 74% on MCN samples for photocatalytic removal of phenol under visible-light irradiation. The highest conversion was obtained on MCN with an initial mass ratio of urea to silica of 5, which has high surface area of 191 m(2) g(-1) and a nanoporous structure with uniform pore-size distribution of 7 nm. In addition to the high activity, the MCN sample also showed high photocatalytic stability.

Matched MeSH terms: Nitriles
Electrochemical Characteristics of a Polymer/Garnet Trilayer Composite Electrolyte for Solid-State Lithium-Metal Batteries

Walle KZ, Musuvadhi Babulal L, Wu SH, Chien WC, Jose R, Lue SJ, et al.

ACS Appl Mater Interfaces, 2021 Jan 20;13(2):2507-2520.
PMID: 33406841 DOI: 10.1021/acsami.0c17422

Although solid-state Li-metal batteries (LMBs) featuring polymer-based solid electrolytes might one day replace conventional Li-ion batteries, the poor Li-ion conductivity of solid polymer electrolytes at low temperatures has hindered their practical applications. Herein, we describe the first example of using a co-precipitation method in a Taylor flow reactor to produce the metal hydroxides of both the Ga/F dual-doped Li7La3Zr2O12 (Ga/F-LLZO) ceramic electrolyte precursors and the Li2MoO4-modified Ni0.8Co0.1Mn0.1O2 (LMO@T-LNCM 811) cathode materials for LMBs. The Li/Nafion (LiNf)-coated Ga/F-LLZO (LiNf@Ga/F-LLZO) ceramic filler was finely dispersed in the poly(vinylidene fluoride)/polyacrylonitrile/lithium bis(trifluoromethanesulfonimide)/succinonitrile matrix to give a trilayer composite polymer electrolyte (denoted "Tri-CPE") through a simple solution-casting. The bulk ionic conductivity of the Tri-CPE at room temperature was approximately 4.50 × 10-4 S cm-1 and exhibited a high Li+ ion transference number (0.84). It also exhibits a broader electrochemical window of 1-5.04 V versus Li/Li+. A full cell based on a CR2032 coin cell containing the LMO@T-LNCM811-based composite cathode, when cycled under 1 C/1 C at room temperature for 300 cycles, achieved an average Columbic efficiency of 99.4% and a capacity retention of 89.8%. This novel fabrication strategy for Tri-CPE structures has potential applications in the preparation of highly safe high-voltage cathodes for solid-state LMBs.

Matched MeSH terms: Nitriles
Green carbonaceous material‒fibrous silica-titania composite photocatalysts for enhanced degradation of toxic 2-chlorophenol

Azami MS, Jalil AA, Hassan NS, Hussain I, Fauzi AA, Aziz MAA

J Hazard Mater, 2021 07 15;414:125524.
PMID: 33647620 DOI: 10.1016/j.jhazmat.2021.125524

In this work, fibrous silica-titania (FST) was successfully prepared by the microemulsion method prior to the addition of three types of carbonaceous materials: graphitic-carbon nitride, g-C3N4 (CN), graphene nanoplatelets (GN), and multi-wall carbon nanotubes, MWCNT (CNT), via a solid-state microwave irradiation technique. The catalysts were characterized using XRD, FESEM, TEM, FTIR, UV-Vis DRS, N2 adsorption-desorption, XPS and ESR, while their photoactivity was examined on the degradation of toxic 2-chlorophenol (2-CP). The result demonstrated that the initial reaction rate was in the following order: CNFST (5.1 × 10-3 mM min-1) > GNFST (2.5 × 10-3 mM min-1) > CNTFST (2.3 × 10-3 mM min-1). The best performance was due to the polymeric structure of g-C3N4 with a good dispersion of C and N on the surface FST. This dispersion contributed towards an appropriate quantity of defect sites, as a consequence of the greater interaction between g-C3N4 and the FST support, that led to narrowed of band gap energy (2.98 eV to 2.10 eV). The effect of scavenger and ESR studies confirmed that the photodegradation over CNFST occurred via a Z-scheme mechanism. It is noteworthy that the addition of green carbonaceous materials on the FST markedly enhanced the photodegradation of toxic 2-CP.

Matched MeSH terms: Nitriles
Fulltext The Synthesis, Characterization, Cytotoxic Activity Assessment and Structure-Activity Relationship of 4-Aryl-6-(2,5-dichlorothiophen-3-yl)-2-methoxypyridine-3-carbonitriles

Al-Refai M, Ibrahim MM, Azmi MN, Osman H, Bakar MHA, Geyer A

Molecules, 2019 Nov 10;24(22).
PMID: 31717690 DOI: 10.3390/molecules24224072

A series of 2-methoxypyridine-3-carbonitrile (5a-i)-bearing aryl substituents were successfully synthesized in good yields by the condensation of chalcones (4a-i) with malononitrile in basic medium. The condensation process, in most cases, offers a route to a variety of methoxypyridine derivatives (6a-g) as side products in poor yields. All new compounds were fully characterized using different spectroscopic methods. Mass ESI-HMRS measurements were also performed. Furthermore, these compounds were screened for their in vitro cytotoxicity activities against three cancer cell lines; namely, those of the liver (line HepG2), prostate (line DU145) and breast (line MBA-MB-231). The cytotoxicity assessment revealed that compounds 5d, 5g, 5h and 5i exhibit promising antiproliferative effects (IC50 1-5 µM) against those three cancer cell lines.

Matched MeSH terms: Nitriles
Utilization of gum polysaccharide of Araucaria heterophylla and Azadirachta indica for encapsulation of cyfluthrin loaded super paramagnetic iron oxide nanoparticles for mosquito larvicidal activity

Samrot AV, Bhavya KS, Angalene JLA, Roshini SM, Preethi R, Steffi SM, et al.

Int J Biol Macromol, 2020 Jun 15;153:1024-1034.
PMID: 31751703 DOI: 10.1016/j.ijbiomac.2019.10.232

Surface engineering of super paramagnetic iron oxide nanoparticles (SPIONs) favor the tagging of any molecule or compound onto it, encapsulating them with a biopolymer make them biocompatible and favor slow release of loaded molecules. Recovery of SPIONs is easier as they obey to external magnetic field. In this study, SPIONS were used for mosquito larvicidal activity after surface engineered with oleic acid to favor the tagging of Cyfluthrin (mosquito larvicidal agent), it was then encapsulated with gum polysaccharide derived from Azadirachta indica and Araucaria heterophylla. Every stage of coreshell formation was microscopically and spectroscopically characterized. The coreshell SPIONs produced using Azadirachta indica and Araucaria heterophylla gum derived polysaccharide encapsulation were found to be the size around 80 nm. Thus, prepared coreshell SPIONs was subjected for mosquito larvicidal activity against Culex sp. The coreshell SPIONs was efficiently killing the mosquito larva and its impact was studied by percentage mortality studies.

Matched MeSH terms: Nitriles
Computational evaluation of unsaturated carbonitriles as neutral receptor model for beryllium(II) recognition

Rosli AN, Ahmad MR, Alias Y, Zain SM, Lee VS, Woi PM

J Mol Model, 2014 Dec;20(12):2533.
PMID: 25433601 DOI: 10.1007/s00894-014-2533-9

Design of neutral receptor molecules (ionophores) for beryllium(II) using unsaturated carbonitrile models has been carried out via density functional theory, G3, and G4 calculations. The first part of this work focuses on gas phase binding energies between beryllium(II) and 2-cyano butadiene (2-CN BD), 3-cyano propene (3-CN P), and simpler models with two separate fragments; acrylonitrile and ethylene. Interactions between beryllium(II) and cyano nitrogen and terminal olefin in the models have been examined in terms of geometrical changes, distribution of charge over the entire π-system, and rehybridization of vinyl carbon orbitals. NMR shieldings and vibrational frequencies probed charge centers and strength of interactions. The six-membered cyclic complexes have planar structures with the rehybridized carbon slightly out of plane (16° in 2-CN BD). G3 results show that in 2-CN BD complex participation of vinyl carbon further stabilizes the cyclic adduct by 16.3 kcal mol(-1), whereas, in simpler models, interaction between beryllium(II) and acetonitrile is favorable by 46.4 kcal mol(-1) compared with that of ethylene. The terminal vinyl carbon in 2-CN BD rehybridizes to sp (3) with an increase of 7 % of s character to allow interaction with beryllium(II). G4 calculations show that the Be(II) and 2-CN BD complex is more strongly bound than those with Mg(II) and Ca(II) by 98.5 and 139.2 kcal mol(-1) (-1), respectively. QST2 method shows that the cyclic and acyclic forms of Be(II)-2-CN BD complexes are separated by 12.3 kcal mol(-1) barrier height. Overlap population analysis reveals that Ca(II) can be discriminated based on its tendency to form ionic interaction with the receptor models.

Matched MeSH terms: Nitriles/chemistry*
Persistence of cyfluthrin in three Malaysian agricultural soils under laboratory conditions

Lee-Yin C, Ismaill BS, Salmijah S, Halimah M

J Environ Biol, 2013 Sep;34(5):957-61.
PMID: 24558812

The influence of temperature, moisture and organic matter on the persistence of cyfluthrin was determined using three types of Malaysian soils, namely clay, clay loam and sandy clay loam obtained from a tomato farm in Cameron Highlands, Pahang. The persistence of cyfluthrin was observed in the laboratory at two temperature levels of 25 and 35 degreeC and field water capacity of 30 and 80%. Treated soil samples were incubated in a growth chamber for 1, 2, 3, 5, 7, 10, 14, 21 and 28 days. The results from the incubation studies showed that temperature and organic matter content significantly reduced the half-life (t1/2) values of cyfluthrin in the three soil types, but moisture content had very little effect. It was observed that cyfluthrin persisted longer at lower temperature and moisture content and higher organic matter content in all the three soil types. The present study demonstrated that under the tropical conditions of Malaysia, cyfluthrin dissipated rapidly in soils compared to its dissipation in soils of temperate regions, evidently due to high temperature.

Matched MeSH terms: Nitriles/metabolism*
Mesoporous carbon nitride for adsorption and fluorescence sensor of N-nitrosopyrrolidine

Sam MS, Lintang HO, Sanagi MM, Lee SL, Yuliati L

Spectrochim Acta A Mol Biomol Spectrosc, 2014 Apr 24;124:357-64.
PMID: 24503155 DOI: 10.1016/j.saa.2013.12.113

A metal-free mesoporous carbon nitride (MCN) was investigated for the first time as an adsorbent for N-nitrosopyrrolidine (NPYR), which is one of the nitrosamine pollutants. Under the same condition, the adsorption capability of the MCN was found to be higher than that of the MCM-41. Since the adsorption isotherm was consistent with Langmuir and Freundlich model equations, it was suggested that the adsorption of NPYR molecules on the MCN occurred in the form of mono-molecular layer on the heterogeneous surface sites. It was proposed that MCN with suitable adsorption sites was beneficial for the adsorption of NPYR. The evidence on the interaction between the NPYR molecules and the MCN was supported by fluorescence spectroscopy. Two excitation wavelengths owing to the terminal N-C and N=C groups were used to monitor the interactions between the emission sites of the MCN and the NPYR molecules. It was confirmed that the intensity of the emission sites was quenched almost linearly with the concentration of NPYR. This result obviously suggested that the MCN would be applicable as a fluorescence sensor for detection of the NPYR molecules. From the Stern-Volmer plot, the quenching rate constant of terminal N-C groups was determined to be ca. two times higher than that of the N=C groups on MCN, suggesting that the terminal N-C groups on MCN would be the favoured sites interacted with the NPYR. Since initial concentration can be easily recovered, the interactions of NPYR on MCN were weak and might only involve electrostatic interactions.

Matched MeSH terms: Nitriles/chemistry*
Permethrin resistance in Aedes albopictus (Diptera: Culicidae) and associated fitness costs

Chan HH, Zairi J

J Med Entomol, 2013 Mar;50(2):362-70.
PMID: 23540125

Insecticide resistance has become a serious issue in vector management programs. Information on insecticidal resistance and its associated mechanisms is important for successful insecticide resistance management. The selection of a colony of permethrin-resistant Aedes albopictus (Skuse) (Diptera: Culicidae), originating from Penang Island, Malaysia, yielded high larval-specific resistance to permethrin and cross-resistance to deltamethrin. Synergism assays showed that the major mechanism underlying this resistance involves cytochrome P450 monooxygenase. The resistance is autosomal, polygenically inherited and incompletely dominant (D = 0.26). Resistant larvae were reared under different conditions to assess the fitness costs. Under high larval density, larval development time of the resistant SGI strain was significantly longer than the susceptible VCRU strain. In both high- and low-density conditions SGI showed a lower rate of emergence and survival compared with the VCRU strain. Resistant larvae were more susceptible to predation by Toxorhynchites splendens (Wiedemann) (Diptera: Culicidae) larvae. The body size of SGI females reared under high-density conditions was larger compared with females of the susceptible strain. SGI females survived longer when starved than did VCRU females. The energy reserve upon eclosion was positively correlated with the size of the adults.

Matched MeSH terms: Nitriles/pharmacology*
Alkyl amides and nitriles as novel tracers for biomass burning

Rushdi AI, bin Abas MR, Didyk BM

Environ Sci Technol, 2003 Jan 1;37(1):16-21.
PMID: 12542285

The occurrence of n-alkanoic acids, amides, and nitriles in samples of aerosol particulate matter from Kuala Lumpur and Santiago suggests that emissions from cooking and biomass burning are the primary sources of these organic markers in the atmosphere. It is proposed that fatty acids react with ammonia during biomass burning or combustion to produce amides and nitriles, which can be applied as useful biomarker tracers. To test this hypothesis, nonadecanoic acid and hexadecanamide were used as reactants in hydrous pyrolysis experiments. These experiments produced amides and nitriles and indicated that ammonia is an essential agent in their formation. Thus amides and nitriles are of utility as indicators for input from combustion and biomass burning in the ambient atmosphere.

Matched MeSH terms: Nitriles/analysis*
Adulticidal Susceptibility Evaluation of Aedes albopictus Using New Diagnostic Doses in Penang Island, Malaysia

Rahim J, Ahmad AH, Ahmad H, Ishak IH, Rus AC, Maimusa HA

J Am Mosq Control Assoc, 2017 Sep;33(3):200-208.
PMID: 28854111 DOI: 10.2987/16-6607R.1

Insecticide-based vector control approaches are facing challenges due to the development of resistance in vector mosquitoes. Therefore, a proper resistance surveillance program using baseline lethal concentrations is crucial for resistance management strategies. Currently, the World Health Organization's (WHO) diagnostic doses established for Aedes aegypti and Anopheles species are being used to study the resistance status of Aedes albopictus. In this study, we established the diagnostic doses for permethrin, deltamethrin, and malathion using a known susceptible reference strain. Five field-collected populations were screened against these doses, following the WHO protocol. This study established the diagnostic dose of malathion at 2.4%, permethrin at 0.95%, and deltamethrin at 0.28%, which differ from the WHO doses for Aedes aegypti and Anopheles spp. Among the insecticides tested on the 5 wild populations, only deltamethrin showed high effectiveness. Different susceptibility and resistance patterns were observed with permethrin, malathion, and dichloro-diphenyl-trichloroethane (DDT) at 4%. This study may assist the health authorities to improve future chemical-based vector control operations in dengue-endemic areas.

Matched MeSH terms: Nitriles/pharmacology*
Photocatalytic degradation of oilfield produced water using graphitic carbon nitride embedded in electrospun polyacrylonitrile nanofibers

Alias NH, Jaafar J, Samitsu S, Yusof N, Othman MHD, Rahman MA, et al.

Chemosphere, 2018 Aug;204:79-86.
PMID: 29653325 DOI: 10.1016/j.chemosphere.2018.04.033

Separation and purification of oilfield produced water (OPW) is a major environmental challenge due to the co-production of the OPW during petroleum exploration and production operations. Effective capture of oil contaminant and its in-situ photodegradation is one of the promising methods to purify the OPW. Based on the photocatalytic capability of graphitic carbon nitride (GCN) which was recently rediscovered, photodegradation capability of GCN for OPW was investigated in this study. GCN was synthesized by calcination of urea and further exfoliated into nanosheets. The GCNs were incorporated into polyacrylonitrile nanofibers using electrospinning, which gave a liquid-permeable self-supporting photocatalytic nanofiber mat that can be handled by hand. The photocatalytic nanofiber demonstrated 85.4% degradation of OPW under visible light irradiation, and improved the degradation to 96.6% under UV light. Effective photodegradation of the photocatalytic nanofiber for OPW originates from synergetic effects of oil adsorption by PAN nanofibers and oil photodegradation by GCNs. This study provides an insight for industrial application on purification of OPW through photocatalytic degradation under solar irradiation.

Matched MeSH terms: Nitriles/chemistry*
Sonophotocatalytic degradation of bisphenol A and its intermediates with graphitic carbon nitride

Sunasee S, Leong KH, Wong KT, Lee G, Pichiah S, Nah I, et al.

Environ Sci Pollut Res Int, 2019 Jan;26(2):1082-1093.
PMID: 28290089 DOI: 10.1007/s11356-017-8729-7

Since bisphenol A (BPA) exhibits endocrine disrupting action and high toxicity in aqueous system, there are high demands to remove it completely. In this study, the BPA removal by sonophotocatalysis coupled with nano-structured graphitic carbon nitride (g-C3N4, GCN) was conducted with various batch tests using energy-based advanced oxidation process (AOP) based on ultrasound (US) and visible light (Vis-L). Results of batch tests indicated that GCN-based sonophotocatalysis (Vis-L/US) had higher rate constants than other AOPs and especially two times higher degradation rate than TiO2-based Vis-L/US. This result infers that GCN is effective in the catalytic activity in Vis-L/US since its surface can be activated by Vis-L to transport electrons from valence band (VB) for utilizing holes (h+VB) in the removal of BPA. In addition, US irradiation exfoliated the GCN effectively. The formation of BPA intermediates was investigated in detail by using high-performance liquid chromatography-mass spectrometry (HPLC/MS). The possible degradation pathway of BPA was proposed.

Matched MeSH terms: Nitriles/chemistry*

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