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Enhancing a search for traditional medicinal plants with anthelmintic action by using wild type and stress reporter Caenorhabditis elegans strains as screening tools

Kumarasingha R, Palombo EA, Bhave M, Yeo TC, Lim DS, Tu CL, et al.

Int J Parasitol, 2014 Apr;44(5):291-8.
PMID: 24583111 DOI: 10.1016/j.ijpara.2014.01.008

Traditional healers in Sarawak, Malaysia, use plants such as Picria fel-terrae, Linariantha bicolor and Lansium domesticum to treat gastrointestinal infections. This study aimed to test whether their nematocidal activities could be confirmed in vitro using highly standardised Caenorhabditis elegans models. We applied eight different ethanol solubilised plant extracts and two commercial anthelmintic drugs to larval and adult stages of C. elegans in vitro. Seven C. elegans strains were evaluated, one wild type and six strains with GFP-tagged stress response pathways to help characterise and compare the pathways affected by plant extracts. Our in vitro screen confirmed that both of the commercial anthelmintic drugs and five of the eight traditionally used plant extracts had significant nematocidal activity against both larval and adult C. elegans. The most effective extracts were from P. fel-terrae. The plant extracts triggered different stress response pathways from the commercial anthelmintic drugs. This study showed that using traditional knowledge of plant medicinal properties in combination with a C. elegans in vitro screen provided a rapid and economical test with a high hit rate compared with the random screening of plants for nematocidal activities. The use of transgenic C. elegans strains may allow this approach to be refined further to investigate the mode of action of active extracts.

Matched MeSH terms: Larva/drug effects
Mosquitocidal activity of a native Bacillus thuringiensis isolate Bt ReX02 from Gunung Jerai Forest, Malaysia against Culex quinquefasciatus and Aedes albopictus

Lakxmy AP, Xavier R, Reenajosephine CM, Lee YW, Marimuthu K, Kathiresan S, et al.

Eur Rev Med Pharmacol Sci, 2011 Feb;15(2):149-55.
PMID: 21434481

To evaluate the mosquito larvicidal potential of the native Bacillus thuringiensis isolate BtReXO2, which was isolated from a tropical rain forest ecosystem in Malaysia. This study also aimed at determining the phenotypic and biochemical characteristics of the isolate.

Matched MeSH terms: Larva/drug effects
Bioefficacy of Insect Growth Regulators Against Aedes albopictus (Diptera: Culicidea) From Sarawak, Malaysia: A Statewide Survey

Lau KW, Chen CD, Lee HL, Low VL, Sofian-Azirun M

J Econ Entomol, 2018 05 28;111(3):1388-1394.
PMID: 29617840 DOI: 10.1093/jee/toy071

The susceptibility status of Aedes albopictus (Skuse; Diptera: Culicidea) larvae collected from 13 districts in Sarawak state, Malaysia was evaluated against five insect growth regulators (IGRs) namely, methoprene, pyriproxyfen, diflubenzuron, cyromazine, and novaluron. Field populations of Ae. albopictus were susceptible to methoprene, pyriproxyfen, cyromazine and novaluron with resistance ratios (RRs) ranging from 0.19-0.38, 0.05-0.14, 0.50-0.95, and 0.75-1.00, respectively. Nevertheless, tolerance towards diflubenzuron (0.33-1.33) was observed in this study. In general, these IGRs exhibited promising results and can be used as alternative control agents against field populations of Ae. albopictus in Sarawak, Malaysia.

Matched MeSH terms: Larva/drug effects
Toxicity of phenol on Macrobrachium rosenbergii (de Man) eggs, larvae, and post-larvae

Law AT, Yeo ME

Bull Environ Contam Toxicol, 1997 Mar;58(3):469-74.
PMID: 9008059
Matched MeSH terms: Larva/drug effects
Fulltext Glutathion S-transferase activity and DDT-susceptibility of Malaysian mosquitos

Lee HL, Chong WL

Southeast Asian J. Trop. Med. Public Health, 1995 Mar;26(1):164-7.
PMID: 8525405

Comparative DDT-susceptibility status and glutathion s-transferase (GST) activity of Malaysian Anopheles maculatus, Culex quinquefasciatus and Aedes aegypti was investigated to ascertain the role of this enzyme in DDT resistance. The standardised WHO dose-mortality bioassay tests were used to determine DDT susceptibility in these mosquitos, whilst GST microassay (Brogdon and Barber, 1990) was conducted to measure the activity of this enzyme in mosquito homogenate. It appeared that DDT susceptibility status of Malaysian mosquitos was not correlated with GST activity.

Matched MeSH terms: Larva/drug effects
Aedes aegypti(Linnaeus) larvae from dengue outbreak areas in Selangor showing resistance to pyrethroids but susceptible to organophosphates

Leong CS, Vythilingam I, Wong ML, Wan Sulaiman WY, Lau YL

Acta Trop, 2018 Sep;185:115-126.
PMID: 29758171 DOI: 10.1016/j.actatropica.2018.05.008

The resistance status of Selangor Aedes aegypti (Linnaeus) larvae against four major groups of insecticides (i.e., organochlorines, carbamates, organophosphates and pyrethroids) was investigated. Aedes aegypti were susceptible against temephos (organophosphate), although resistance (RR50 = 0.21-2.64) may be developing. The insecticides susceptibility status of Ae. aegypti larvae were found heterogeneous among the different study sites. Results showed that Ae. aegypti larvae from Klang, Sabak Bernam and Sepang were susceptible against all insecticides tested. However, other study sites exhibited low to high resistance against all pyrethroids (RR50 = 1.19-32.16). Overall, the application of synergists ethacrynic acid, S.S.S.- tributylphosphorotrithioate and piperonyl butoxide increased the toxicity of insecticides investigated. However, the application failed to increase the mortality to susceptible level (>97%) for certain populations, therefore there are chances of alteration of target site resistance involved. Biochemical assays revealed that α-esterase, (Gombak, Kuala Langat, Kuala Selangor and Sabak Bernam strains) β-esterase (Klang and Sabak Bernam strains), acetylcholinesterase (Kuala Selangor and Sabak Bernam strains), glutathione-S-transferase (Kuala Selangor and Sabak Bernam strains) and mono-oxygenases (Gombak, Hulu Langat, Hulu Selangor and Kuala Langat strains) were elevated. Spearman rank-order correlation indicated a significant correlation between resistance ratios of: DDT and deltamethrin (r = 0.683, P = 0.042), cyfluthrin and deltamethrin (r = 0.867, P =0.002), cyflyuthrin and lambdacyhalothrin (r = 0.800, P =0.010), cyfluthrin and permethrin (r = 0.770, P =0.015) deltamethrin and permethrin (r = 0.803, P =0.088), propoxur and malathion (r = 0.867, P = 0.002), malathion and temephos (r = 0.800, P = 0.010), etofenprox and MFO enzyme (r = 0.667, P =0.050). The current study provides baseline information for vector control programs conducted by local authorities. The susceptibility status of Ae. aegypti should be monitored sporadically to ensure the effectiveness of current vector control strategy in Selangor.

Matched MeSH terms: Larva/drug effects*
Fulltext Evaluation of Sumithion L-40 against Aedes aegypti (L.) and Aedes albopictus Skuse

Loke SR, Sing KW, Teoh GN, Lee HL

Trop Biomed, 2015 Mar;32(1):76-83.
PMID: 25801256 MyJurnal

Space spraying of chemical insecticides is still an important mean of controlling Aedes mosquitoes and dengue transmission. For this purpose, the bioefficacy of space-sprayed chemical insecticide should be evaluated from time to time. A simulation field trial was conducted outdoor in an open field and indoor in unoccupied flat units in Kuala Lumpur, to evaluate the adulticidal and larvicidal effects of Sumithion L-40, a ULV formulation of fenitrothion. A thermal fogger with a discharge rate of 240 ml/min was used to disperse Sumithion L-40 at 3 different dosages (350 ml/ha, 500 ml/ha, 750 ml/ha) against lab-bred larvae and adult female Aedes aegypti and Aedes albopictus. An average of more than 80% adult mortality was achieved for outdoor space spray, and 100% adult mortality for indoor space spray, in all tested dosages. Outdoor larvicidal effect was noted up to 14 days and 7 days at a dosage of 500 and 750 ml/ha for Ae. aegypti and Ae. albopictus, respectively. Indoor larvicidal effect was up to 21 days (500 ml/ha) and 14 days (750 ml/ha), respectively, after spraying with larval mortality > 50% against Ae. aegypti. This study concluded that the effective dosage of Sumithion L-40 thermally applied against adult Ae. aegypti and Ae. albopictus indoor and outdoor is 500 and 750 ml/ha. Based on these dosages, effective indoor spray volume is 0.4 - 0.6 ml/m³. Additional indoor and outdoor larvicidal effect will be observed at these application dosages, in addition to adult mortality.

Matched MeSH terms: Larva/drug effects
Fulltext Susceptibility of field-collected Aedes aegypti (L.) (Diptera: Culicidae) to Bacillus thuringiensis israelensis and temephos

Loke SR, Andy-Tan WA, Benjamin S, Lee HL, Sofian-Azirun M

Trop Biomed, 2010 Dec;27(3):493-503.
PMID: 21399591 MyJurnal

The susceptibility status of field-collected Aedes aegypti (L.) from a dengue endemic area to Bacillus thuringiensis israelensis (Bti) and temephos was determined. Since August 2007, biweekly ovitrap surveillance (OS) was conducted for 12 mo in 2 sites, A & B, in Shah Alam, Selangor. Site A was treated with a Bti formulation, VectoBac® WG at 500 g/ha, from December 2007 - June 2008 while Site B was subjected to routine dengue vector control activities conducted by the local municipality. Aedes aegypti larvae collected from OS in both sites were bred until F3 and evaluated for their susceptibility. The larvae were pooled according to 3 time periods, which corresponded to Bti treatment phases in site A: August - November 2007 (Bti pre-treatment phase); December 2007 - June 2008 (Bti treatment phase); and July - September 2008 (Bti post-treatment phase). Larvae were bioassayed against Bti or temephos in accordance with WHO standard methods. Larvae collected from Site A was resistant to temephos, while incipient temephos resistant was detected in Site B throughout the study using WHO diagnostic dosage of 0.02 mg/L. The LC50 of temephos ranged between 0.007040 - 0.03799 mg/L throughout the year in both sites. Resistance ratios (LC50) indicated that temephos resistance increased with time, from 1.2 - 6.7 folds. The LC50 of Ae. aegypti larvae to Bti ranged between 0.08890 - 0.1814 mg/L throughout the year in both sites, showing uniform susceptibility of field larvae to Bti, in spite of Site A receiving 18 Bti treatments over a period of 7 mo. No cross-resistance of Ae. aegypti larvae from temephos to Bti was detected.

Matched MeSH terms: Larva/drug effects
Influence of paraquat on Chrysomya megacephala (Fabricius) (Diptera: Calliphoridae) infesting minced-beef substrates in Kelantan, Malaysia

Mahat NA, Yin CL, Jayaprakash PT

J Forensic Sci, 2014 Mar;59(2):529-32.
PMID: 24745083

This study investigated the influence of paraquat, a prevalent poison used by suicides, on initial oviposition and development of Chrysomya megacephala (Fabricius) using minced-beef substrates. Paraquat in lethal dose for human (40 mg/kg), two times the lethal dose (80 mg/kg) and five times the lethal dose (200 mg/kg) were mixed thoroughly with respective minced-beef substrates (1 kg each) that were decomposed in a shaded habitat fully protected from rain. Results of four replications of the above experiment revealed that the presence of paraquat neither delayed initial oviposition nor prolonged the developmental stages of C. megacephala. Therefore, estimation of postmortem interval (PMI) based on empirical baseline data obtained using animal models devoid of any poisons would still be appropriate for estimating PMI in paraquat-related deaths.

Matched MeSH terms: Larva/drug effects
Fulltext Malathion extraction from larvae of Chrysomya megacephala (Fabricius) (Diptera: Calliphoridae) for determining death due to malathion

Mahat NA, Jayaprakash PT, Zafarina Z

Trop Biomed, 2012 Mar;29(1):9-17.
PMID: 22543598 MyJurnal

The use of Chrysomya megacephala larvae for detecting malathion for diagnosing the cause of death was investigated. This could prove useful when the visceral organs have become liquefied during decomposition and therefore cannot be sampled. A field experiment was conducted in which C. megacephala were allowed to colonise naturally the corpses of rabbits that had died of malathion poisoning. The concentration of malathion increased gradually during the larval stages of C. megacephala reaching the maximum concentration in the third instar larvae. The concentration of malathion declined during prepupal stage and reached its lowest level among tenerals. The average malathion concentrations in C. megacephala growing in poisoned rabbit corpses left in a sunlit habitat were significantly higher (p<0.05) than those growing on poisoned rabbits left in a shaded habitat. The concentrations of malathion in the different stages of development of C. megacephala were moderately correlated (r = 0.51-0.69) with the administered doses as well as with those estimated in visceral organs. Thus, it would not be reliable to suggest the formulation of mathematical algorithms for relating the concentration of malathion found in the different stages of development of C. megacephala with those found in the visceral organs. However, in the context of forensic investigation, the qualitative detection of malathion in C. megacephala may prove useful in diagnosing the cause of death, since malathion is a common cause of accidental and suicidal deaths.

Matched MeSH terms: Larva/drug effects
Fulltext Toxicity of buprofezin on the survival of embryo and larvae of African catfish, Clarias gariepinus (Bloch)

Marimuthu K, Muthu N, Xavier R, Arockiaraj J, Rahman MA, Subramaniam S

PLoS One, 2013;8(10):e75545.
PMID: 24098390 DOI: 10.1371/journal.pone.0075545

Buprofezin is an insect growth regulator and widely used insecticide in Malaysia. The present study evaluated the toxic effects of buprofezin on the embryo and larvae of African catfish (Clarias gariepinus) as a model organism. The embryos and larvae were exposed to 7 different concentrations (0, 0.05, 0.5, 5, 25, 50 and 100 mg/L) of buprofezin. Each concentration was assessed in five replicates. Eggs were artificially fertilized and 200 eggs and larvae were subjected to a static bath treatment for all the concentrations. The mortality of embryos was significantly increased with increasing buprofezin concentrations from 5 to 100 mg/L (p< 0.05). However, the mortality was not significantly different (p<0.05) among the following concentrations: 0 (control), 0.05, 0.5 and 5 mg/L. Data obtained from the buprofezin acute toxicity tests were evaluated using probit analysis. The 24 h LC50 value (with 95% confidence limits) of buprofezin for embryos was estimated to be 6.725 (3.167-15.017) mg/L. The hatching of fish embryos was recorded as 68.8, 68.9, 66.9, 66.4, 26.9, 25.1 and 0.12% in response to 7 different concentrations of buprofezin, respectively. The mortality rate of larvae significantly (p<0.05) increased with increasing buprofezin concentrations exposed to 24-48 h. The 24 and 48 h LC50 values (with 95% confidence limits) of buprofezin for the larvae was estimated to be 5.702 (3.198-8.898) and 4.642 (3.264-6.287) mg/L respectively. There were no significant differences (p>0.05) in the LC50 values obtained at 24 and 48 h exposure times. Malformations were observed when the embryos and larvae exposed to more than 5 mg/L. The results emerged from the study suggest that even the low concentration (5 mg/L) of buprofezin in the aquatic environment may have adverse effect on the early embryonic and larval development of African catfish.

Matched MeSH terms: Larva/drug effects
Fulltext Long-Term Resistance of Drosophila melanogaster to the Mushroom Toxin Alpha-Amanitin

Mitchell CL, Yeager RD, Johnson ZJ, D'Annunzio SE, Vogel KR, Werner T

PLoS One, 2015;10(5):e0127569.
PMID: 25978397 DOI: 10.1371/journal.pone.0127569

Insect resistance to toxins exerts not only a great impact on our economy, but also on the ecology of many species. Resistance to one toxin is often associated with cross-resistance to other, sometimes unrelated, chemicals. In this study, we investigated mushroom toxin resistance in the fruit fly Drosophila melanogaster (Meigen). This fruit fly species does not feed on mushrooms in nature and may thus have evolved cross-resistance to α-amanitin, the principal toxin of deadly poisonous mushrooms, due to previous pesticide exposure. The three Asian D. melanogaster stocks used in this study, Ama-KTT, Ama-MI, and Ama-KLM, acquired α-amanitin resistance at least five decades ago in their natural habitats in Taiwan, India, and Malaysia, respectively. Here we show that all three stocks have not lost the resistance phenotype despite the absence of selective pressure over the past half century. In response to α-amanitin in the larval food, several signs of developmental retardation become apparent in a concentration-dependent manner: higher pre-adult mortality, prolonged larva-to-adult developmental time, decreased adult body size, and reduced adult longevity. In contrast, female fecundity nearly doubles in response to higher α-amanitin concentrations. Our results suggest that α-amanitin resistance has no fitness cost, which could explain why the resistance has persisted in all three stocks over the past five decades. If pesticides caused α-amanitin resistance in D. melanogaster, their use may go far beyond their intended effects and have long-lasting effects on ecosystems.

Matched MeSH terms: Larva/drug effects
Fulltext Sterilisation of Lucilia cuprina Wiedemann maggots used in therapy of intractable wounds

Mohd Masri S, Nazni WA, Lee HL, T Rogayah TA, Subramaniam S

Trop Biomed, 2005 Dec;22(2):185-9.
PMID: 16883286 MyJurnal

Three new techniques of sterilising maggots of Lucilia cuprina for the purpose of debriding intractable wounds were studied. These techniques were utilisation of ultra-violet C (UVC) and maggot sterilisation with disinfectants. The status of sterility was checked on nutrient agar and blood agar and confirmed with staining. The indicators for the effectiveness of the methods were sterility and survival rate of the eggs or larvae. Egg sterilisation with UVC had the lowest hatching rate (16+/-0.00%) while egg sterilisation with disinfectants showed high hatching rate (36.67+/-4.41%) but low maggot survival rate (31.67+/-1.67%). Sterilisation of the maggots was the most suitable, since the survival rate was the highest (88.67+/-0.88%). Complete sterility was achieved in all cases, except that Proteus mirabilis was consistently found. However, the presence of this microorganism was considered beneficial.

Matched MeSH terms: Larva/drug effects
Hydrothermal synthesis of titanium dioxide nanoparticles: mosquitocidal potential and anticancer activity on human breast cancer cells (MCF-7)

Murugan K, Dinesh D, Kavithaa K, Paulpandi M, Ponraj T, Alsalhi MS, et al.

Parasitol Res, 2016 Mar;115(3):1085-96.
PMID: 26621285 DOI: 10.1007/s00436-015-4838-8

Mosquito vectors (Diptera: Culicidae) are responsible for transmission of serious diseases worldwide. Mosquito control is being enhanced in many areas, but there are significant challenges, including increasing resistance to insecticides and lack of alternative, cost-effective, and eco-friendly products. To deal with these crucial issues, recent emphasis has been placed on plant materials with mosquitocidal properties. Furthermore, cancers figure among the leading causes of morbidity and mortality worldwide, with approximately 14 million new cases and 8.2 million cancer-related deaths in 2012. It is expected that annual cancer cases will rise from 14 million in 2012 to 22 million within the next two decades. Nanotechnology is a promising field of research and is expected to give major innovation impulses in a variety of industrial sectors. In this study, we synthesized titanium dioxide (TiO2) nanoparticles using the hydrothermal method. Nanoparticles were subjected to different analysis including UV-Vis spectrophotometry, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), zeta potential, and energy-dispersive spectrometric (EDX). The synthesized TiO2 nanoparticles exhibited dose-dependent cytotoxicity against human breast cancer cells (MCF-7) and normal breast epithelial cells (HBL-100). After 24-h incubation, the inhibitory concentrations (IC50) were found to be 60 and 80 μg/mL on MCF-7 and normal HBL-100 cells, respectively. Induction of apoptosis was evidenced by Acridine Orange (AO)/ethidium bromide (EtBr) and 4',6-diamidino-2-phenylindole dihydrochloride (DAPI) staining. In larvicidal and pupicidal experiments conducted against the primary dengue mosquito Aedes aegypti, LC50 values of nanoparticles were 4.02 ppm (larva I), 4.962 ppm (larva II), 5.671 ppm (larva III), 6.485 ppm (larva IV), and 7.527 ppm (pupa). Overall, our results suggested that TiO2 nanoparticles may be considered as a safe tool to build newer and safer mosquitocides and chemotherapeutic agents with little systemic toxicity.

Matched MeSH terms: Larva/drug effects
Seaweed-synthesized silver nanoparticles: an eco-friendly tool in the fight against Plasmodium falciparum and its vector Anopheles stephensi?

Murugan K, Samidoss CM, Panneerselvam C, Higuchi A, Roni M, Suresh U, et al.

Parasitol Res, 2015 Nov;114(11):4087-97.
PMID: 26227141 DOI: 10.1007/s00436-015-4638-1

Malaria, the most widespread mosquito-borne disease, affects 350-500 million people each year. Eco-friendly control tools against malaria vectors are urgently needed. This research proposed a novel method of plant-mediated synthesis of silver nanoparticles (AgNP) using a cheap seaweed extract of Ulva lactuca, acting as a reducing and capping agent. AgNP were characterized by UV-vis spectrophotometry, Fourier transform infrared (FTIR) spectroscopy, energy-dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), and X-ray diffraction (XRD). The U. lactuca extract and the green-synthesized AgNP were tested against larvae and pupae of the malaria vector Anopheles stephensi. In mosquitocidal assays, LC50 values of U. lactuca extract against A. stephensi larvae and pupae were 18.365 ppm (I instar), 23.948 ppm (II), 29.701 ppm (III), 37.517 ppm (IV), and 43.012 ppm (pupae). LC50 values of AgNP against A. stephensi were 2.111 ppm (I), 3.090 ppm (II), 4.629 ppm (III), 5.261 ppm (IV), and 6.860 ppm (pupae). Smoke toxicity experiments conducted against mosquito adults showed that U. lactuca coils evoked mortality rates comparable to the permethrin-based positive control (66, 51, and 41%, respectively). Furthermore, the antiplasmodial activity of U. lactuca extract and U. lactuca-synthesized AgNP was evaluated against CQ-resistant (CQ-r) and CQ-sensitive (CQ-s) strains of Plasmodium falciparum. Fifty percent inhibitory concentration (IC50) values of U. lactuca were 57.26 μg/ml (CQ-s) and 66.36 μg/ml (CQ-r); U. lactuca-synthesized AgNP IC50 values were 76.33 μg/ml (CQ-s) and 79.13 μg/ml (CQ-r). Overall, our results highlighted out that U. lactuca-synthesized AgNP may be employed to develop newer and safer agents for malaria control.

Matched MeSH terms: Larva/drug effects
Fulltext Adult and larval insecticide susceptibility status of Culex quinquefasciatus (Say) mosquitoes in Kuala Lumpur Malaysia

Nazni WA, Lee HL, Azahari AH

Trop Biomed, 2005 Jun;22(1):63-8.
PMID: 16880755 MyJurnal

The susceptibility of Culex quinquefasciatus to chemical insecticides in two field sites in Kuala Lumpur was evaluated using the WHO standard susceptibility test. Less then 7 days old female mosquitos, reared from wild caught females were exposed to discriminating dosages of insecticides at recommended exposure periods. The larval bioassay were conducted using the multiple concentrations and the LC50 value was determined. The results indicated that cyfluthrin is the most effective among all the insecticides tested with LT50 value of 29.95 min and 28.59 min, for the strain from Ampang Hill and Pantai Dalam, respectively. It was surprisingly to note that both these field strains showed 0% mortality when tested against malathion and DDT. The LC50 value indicated that both strains were highly resistant to malathion with resistance ratio of 17,988 folds and 14,053 folds, respectively. This concludes that resistance at larval stages is extremely high compared to adult stages.

Matched MeSH terms: Larva/drug effects
Clostridium bifermentans serovar malaysia: characterization of putative mosquito larvicidal proteins

Nicolas L, Charles JF, de Barjac H

FEMS Microbiol Lett, 1993 Oct 01;113(1):23-8.
PMID: 8243978

The toxicity of Clostridium bifermentans serovar malaysia to mosquito larvae is due to protein toxins, belonging to a novel class of insecticidal toxins. Toxic extracts contains three major proteins of 66, 18 and 16 kDa. The 18-kDa and 16-kDa proteins are probably involved in toxicity. They are synthesised during sporulation, concomitant with activity. They are absent from non-toxic strains of C. bifermentans and are present at very low levels in non-toxic C. bifermentans serovar malaysia cultures produced at 42 degrees C. The 66-kDa protein is present throughout the growth phases of C. bifermentans serovar malaysia, and an immunologically related 66-kDa protein is present in non-toxic C. bifermentans strains.

Matched MeSH terms: Larva/drug effects
Fulltext New Marine Antifouling Compounds from the Red Alga Laurencia sp

Oguri Y, Watanabe M, Ishikawa T, Kamada T, Vairappan CS, Matsuura H, et al.

Mar Drugs, 2017 Aug 28;15(9).
PMID: 28846653 DOI: 10.3390/md15090267

Six new compounds, omaezol, intricatriol, hachijojimallenes A and B, debromoaplysinal, and 11,12-dihydro-3-hydroxyretinol have been isolated from four collections of Laurencia sp. These structures were determined by MS and NMR analyses. Their antifouling activities were evaluated together with eight previously known compounds isolated from the same samples. In particular, omaezol and hachijojimallene A showed potent activities (EC50 = 0.15-0.23 µg/mL) against larvae of the barnacle Amphibalanus amphitrite.

Matched MeSH terms: Larva/drug effects*
Cadmium, copper, and zinc toxicity to the clam, Donax faba C., and the blood cockle, Anadara granosa L

Ong ES, Din ZB

Bull Environ Contam Toxicol, 2001 Jan;66(1):86-93.
PMID: 11080341
Matched MeSH terms: Larva/drug effects
Spray coverage and pest management efficacy of a solid set canopy delivery system in high density apples

Owen-Smith P, Perry R, Wise J, Jamil RZR, Gut L, Sundin G, et al.

Pest Manag Sci, 2019 Nov;75(11):3050-3059.
PMID: 30895726 DOI: 10.1002/ps.5421

BACKGROUND: Air blast sprayers are not optimized for spraying the short statured trees in modern apple orchards, resulting in off target drift and variable coverage. A solid set canopy delivery system (SSCDS) consisting of a microsprayer array distributed throughout the orchard was investigated as a replacement agrochemical application method in this study. SSCDS's have the potential to optimize coverage, rapidly spray applications, and remove the operator and tractor from the orchard.
RESULTS: Air blast and SSCDS applications were compared using water sensitive paper, bioassays, and pest damage assessments. Pest management and coverage were compared using application volumes of 700 and 795 L ha-1 , respectively. In 2013, adaxial coverage measurements showed no difference between the treatments, but air blast sprayers had higher coverage levels on the abaxial surfaces. There were no significant differences in coverage in 2014. Bioassays using Choristoneura rosaceana fed on leaf discs treated by the SSCDS displayed 95.8% mortality in 2013 and 94.2% mortality in 2014, and air blast treated larval mortality was 95% in 2013 and 100% in 2014. Damage evaluations in both years generally showed no significant differences between the air blast plots and the SSCDS plots, but significant differences between the treated plots and untreated control.
CONCLUSIONS: The prototype SSCDS was an effective pest management tool in high density apples, and offered a number of advantages over an air blast. Further engineering and research into coverage optimization would offer producers a novel tool for foliar agrochemical applications. © 2019 Society of Chemical Industry.

Matched MeSH terms: Larva/drug effects

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