Studies with Brugia pahangi 12. The activity of levamisole

1976 ◽  
Vol 50 (1) ◽  
pp. 21-28 ◽  
Author(s):  
Rosemary Rogers ◽  
D. A. Denham
Keyword(s):  
Aedes Aegypti ◽  
Developmental Stages ◽  
Brugia Pahangi ◽  
Infective Larvae ◽  
Vector Mosquito ◽  
Third Stage ◽  
Dose Levels

AbstractThe effects of levamisole on adults, third stage infective larvae, and microfilariae of Brugia pahangi were studied in in vitro culture and in vivo against developing stages in the vector mosquito and in infected cats. In vitro the drug was effective only at dose levels much higher than can be tolerated by mammals. It was active against the developmental stages of the worm in the vector Aedes aegypti.The drug was strongly microfilaricidal in cats but less effective against adult worms.

scholarly journals In vitro chemotactic responses of Brugia pahangi infective larvae to sodium ions

2011 ◽  
Vol 86 (4) ◽  
pp. 406-409 ◽  
Author(s):  
Y. Mitsui ◽  
M. Miura ◽  
D.A. Bome ◽  
Y. Aoki
Keyword(s):  
Deionized Water ◽  
Sodium Ions ◽  
Brugia Pahangi ◽  
Low Concentration ◽  
Infective Larvae ◽  
Significant Tendency ◽  
Third Stage

AbstractIn vitro chemotactic responses of infective third-stage larvae (L3) of Brugia pahangi to NaCl, Na2HPO4, KCl, K2HPO4, MgCl2 and CaCl2 were assessed. Compared to deionized water as a control, 200 mm NaCl and 100 mm Na2HPO4 significantly attracted L3 (P < 0.01 and P < 0.01), whereas L3 were likely to avoid 200 mm KCl and 100 mm K2HPO4 (P < 0.05 and P < 0.05). L3 showed no significant tendency to avoid or to be attracted to 200 mm CaCl2 and 200 mm MgCl2. Furthermore, NaCl exhibited a significant chemoattractant activity for L3 at a low concentration of 100 mm.

scholarly journals Anthelminthic effects of extracts of indigenous browses from mid rift valley of Ethiopia

2021 ◽  
Vol 25 (2) ◽  
pp. 132-143
Author(s):  
Amsalu Sisay ◽  
Tegene Negesse ◽  
Ajebu Nurfeta
Keyword(s):  
Developmental Stages ◽  
Negative Control ◽  
In Vitro Assays ◽  
Inhibition Assay ◽  
Egg Hatching ◽  
Acacia Senegal ◽  
Egg Hatch ◽  
Infective Larvae

This study was conducted to evaluate the potential anthelminthic properties of extracts of leaves of indigenous browses (Acacia seyal, Acacia senegal, Acacia tortilis, Millettia ferruginea, and Vernonia amygadalina) based on three in vitro assays. Acetone extracts of browses at different concentrations (75 to 1200 μg/ml, for egg and larvae and 100mg/ml for an adult) were tested on three developmental stages of Haemonchus contortus (eggs, infective larvae, and adult worms) using egg hatch assay (EHA), larval migration inhibition assay (LMIA) and adult worm motility inhibition assay (AMIA). Significant effects were obtained with all five browses but differences were observed depending on the parasitic stages. The effects of five browse extracts on egg hatching were concentration-dependent, the highest (P<0.05) egg hatch inhibition rate was observed at 1200 μg/ml concentration for all browses. All extracts had a higher effect (P<0.01) than that of the negative control, phosphate buffer saline (PBS). In contrast, no concentration-response relationship was found for infective larvae and adult worms, although more potent effects were observed with the highest concentrations. The LMI rate (70%) induced by Vernonia  amygadalina extract, at a concentration of 300 μg/ml, was the highest (P<0.05) of all other browses, even at higher concentrations. The highest LMI rate (62%) induced by Acacia senegal extract at higher concentration, was lower than that of LMI rate (70%) induced by Vernonia amygadalina, at 300 μg/ml concentration. Vernonia amygadalina was found to be highly and rapidly effective against adult worms inducing the highest mortality rate (90%) as soon as 4 hrs after incubation. Overall, the in vitro results suggest that these five  browses do possess anti-parasitic properties and Vernonia amygadalina showed the most effective anti-parasitic property. These effects remain to be confirmed through in vivo study.

In vitro development of Terranova decipiens (Nematoda) (Krabbe, 1878)

1974 ◽  
Vol 52 (4) ◽  
pp. 471-479 ◽  
Author(s):  
G. McClelland ◽  
K. Ronald
Keyword(s):  
Developmental Stages ◽  
Infective Stage ◽  
In Vitro Development ◽  
Infective Larvae ◽  
Complete Development ◽  
Vitro Development

Eggs of Terranova decipiens were dissected from the vagina and uterus of adult worms from seals and incubated in seawater at 15C. Freshly hatched larvae were cultivated to preadults in Eagle's medium (MEM) with 20% fetal-calf serum.At 15C, 70% of the larvae exsheathed and grew to the infective stage without further molts. Infective larvae were 31.3 (27.7–33.3) mm in length after 52 weeks of cultivation and were similar in morphology to larvae from fish.At 35C, 80%. of cultivated larvae (5.0–24.2 mm in length) molted to preadult. There was a 25% increase in length over a 6-week, period. Cultivated preadults (6.1–36.8 mm in length) were morphologically similar to preadults from seals. They did not, however, complete development to adulthood, and an attempt to infect a seal with cultivated infective larvae was unsuccessful.The described in vitro developmental stages of T. decipiens form a useful guide to the in vivo identification of this important economic nematode.

scholarly journals Condensed tannins and gastro-intestinal parasites in sheep

1999 ◽  
pp. 57-61 ◽  
Author(s):  
A.L. Molan ◽  
G.C. Waghorn ◽  
W.C. Mcnabb
Keyword(s):  
Condensed Tannins ◽  
Intestinal Parasites ◽  
In Vitro Assays ◽  
Trichostrongylus Colubriformis ◽  
Egg Hatching ◽  
Infective Larvae ◽  
Third Stage ◽  
Principal Method

As the effectiveness of current anthelmintic drenches is being reduced by the emergence of drench resistance and significant production losses may still occur as a result of continuing larval challenge, strategies for nematode control should focus on preventing the build-up of infective larvae on pasture rather than treating the infection. This paper reports the effects of condensed tannins (CT) extracted from Lotus pedunculatus, Lotus corniculatus, sulla (Hedysarum coronarium) and sainfoin (Onobrychus viciifolia) on in vitro viability of eggs, first stage larvae (L1) and third stage larvae (L3) of the sheep nematode, Trichostrongylus colubriformis. When in vitro assays contained CT in a similar concentrations to that in the digestive tract of sheep fed these forages, the CT reduced the development of eggs to L3 larvae as well as the proportion of eggs hatching. The CT also reduced the development of L1 larvae to L3 larvae and decreased the motility of L3 larvae when assessed by the larval migration inhibition assay and this may reduce their infective capacity in vivo. If these forages are fed to grazing sheep, then it may be possible to reduce contamination of pasture with infective larvae and reduce our dependence on anthelmintics as the principal method for controlling internal parasites. Keywords: condensed tannins, drench resistance, egg hatching, larval development, Lotus, parasites, sainfoin, sulla, Trichostrongylus colubriformis

scholarly journals The Lethal(2)-Essential-for-Life [L(2)EFL] Gene Family Modulates Dengue Virus Infection in Aedes aegypti

2020 ◽  
Vol 21 (20) ◽  
pp. 7520
Author(s):  
Lucky R. Runtuwene ◽  
Shuichi Kawashima ◽  
Victor D. Pijoh ◽  
Josef S. B. Tuda ◽  
Kyoko Hayashida ◽  
...  
Keyword(s):  
Aedes Aegypti ◽  
Dengue Virus ◽  
Cell Line ◽  
Dengue Infection ◽  
Fruit Fly ◽  
Initiation Factor ◽  
Poly I:C ◽  
Gene Products ◽  
Vector Mosquito

Efforts to determine the mosquito genes that affect dengue virus replication have identified a number of candidates that positively or negatively modify amplification in the invertebrate host. We used deep sequencing to compare the differential transcript abundances in Aedes aegypti 14 days post dengue infection to those of uninfected A. aegypti. The gene lethal(2)-essential-for-life [l(2)efl], which encodes a member of the heat shock 20 protein (HSP20) family, was upregulated following dengue virus type 2 (DENV-2) infection in vivo. The transcripts of this gene did not exhibit differential accumulation in mosquitoes exposed to insecticides or pollutants. The induction and overexpression of l(2)efl gene products using poly(I:C) resulted in decreased DENV-2 replication in the cell line. In contrast, the RNAi-mediated suppression of l(2)efl gene products resulted in enhanced DENV-2 replication, but this enhancement occurred only if multiple l(2)efl genes were suppressed. l(2)efl homologs induce the phosphorylation of eukaryotic initiation factor 2α (eIF2α) in the fruit fly Drosophila melanogaster, and we confirmed this finding in the cell line. However, the mechanism by which l(2)efl phosphorylates eIF2α remains unclear. We conclude that l(2)efl encodes a potential anti-dengue protein in the vector mosquito.

scholarly journals Genome-Wide Transcriptomic Identification and Functional Insight of Lily WRKY Genes Responding to Botrytis Fungal Disease

Plants ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 776
Author(s):  
Shipra Kumari ◽  
Bashistha Kumar Kanth ◽  
Ju young Ahn ◽  
Jong Hwa Kim ◽  
Geung-Joo Lee
Keyword(s):  
Abiotic Stress ◽  
Biotic Stress ◽  
Developmental Stages ◽  
Expression Patterns ◽  
Lilium Longiflorum ◽  
Biotic And Abiotic Stress ◽  
Biotic Stresses ◽  
Genome Wide

Genome-wide transcriptome analysis using RNA-Seq of Lilium longiflorum revealed valuable genes responding to biotic stresses. WRKY transcription factors are regulatory proteins playing essential roles in defense processes under environmental stresses, causing considerable losses in flower quality and production. Thirty-eight WRKY genes were identified from the transcriptomic profile from lily genotypes, exhibiting leaf blight caused by Botrytis elliptica. Lily WRKYs have a highly conserved motif, WRKYGQK, with a common variant, WRKYGKK. Phylogeny of LlWRKYs with homologous genes from other representative plant species classified them into three groups- I, II, and III consisting of seven, 22, and nine genes, respectively. Base on functional annotation, 22 LlWRKY genes were associated with biotic stress, nine with abiotic stress, and seven with others. Sixteen unique LlWRKY were studied to investigate responses to stress conditions using gene expression under biotic and abiotic stress treatments. Five genes—LlWRKY3, LlWRKY4, LlWRKY5, LlWRKY10, and LlWRKY12—were substantially upregulated, proving to be biotic stress-responsive genes in vivo and in vitro conditions. Moreover, the expression patterns of LlWRKY genes varied in response to drought, heat, cold, and different developmental stages or tissues. Overall, our study provides structural and molecular insights into LlWRKY genes for use in the genetic engineering in Lilium against Botrytis disease.

The anterior and posterior ‘stomach’ regions of larval Aedes aegypti midgut: regional specialization of ion transport and stimulation by 5-hydroxytryptamine

1999 ◽  
Vol 202 (3) ◽  
pp. 247-252 ◽  
Author(s):  
T.M. Clark ◽  
A. Koch ◽  
D.F. Moffett
Keyword(s):  
Steady State ◽  
Aedes Aegypti ◽  
Ion Transport ◽  
Malpighian Tubules ◽  
Transport Mechanisms ◽  
Regional Specialization ◽  
Negative Deflection ◽  
Electrical Polarity

The ‘stomach’ region of the larval mosquito midgut is divided into histologically distinct anterior and posterior regions. Anterior stomach perfused symmetrically with saline in vitro had an initial transepithelial potential (TEP) of −66 mV (lumen negative) that decayed within 10–15 min to a steady-state TEP near −10 mV that was maintained for at least 1 h. Lumen-positive TEPs were never observed in the anterior stomach. The initial TEP of the perfused posterior stomach was opposite in polarity, but similar in magnitude, to that of the anterior stomach, measuring +75 mV (lumen positive). This initial TEP of the posterior stomach decayed rapidly at first, then more slowly, eventually reversing the electrical polarity of the epithelium as lumen-negative TEPs were recorded in all preparations within 70 min. Nanomolar concentrations of the biogenic amine 5-hydroxytryptamine (5-HT, serotonin) stimulated both regions, causing a negative deflection of the TEP of the anterior stomach and a positive deflection of the TEP of the posterior stomach. Phorbol 12,13-diacetate also caused a negative deflection of the TEP of the anterior stomach, but had no effect on the TEP of the posterior stomach. These data demonstrate that 5-HT stimulates region-specific ion-transport mechanisms in the stomach of Aedes aegypti and suggest that 5-HT coordinates the actions of the Malpighian tubules and midgut in the maintenance of an appropriate hemolymph composition in vivo.

PROTEÍNA NÃO-ESTRUTURAL (NS1) COMO FERRAMENTA DIAGNÓSTICA PRECOCE E ALVO TERAPÊUTICO NA DENGUE

2021 ◽  
Author(s):  
Ana Vitória Gomes Alves
Keyword(s):  
Aedes Aegypti

Introdução: A dengue é uma arbovirose tropical negligenciada mundialmente, transmitida pelo Aedes aegypti. A proteína não-estrutural 1 (NS1) está presente nos quatro sorotipos da dengue, e é um importante marcador de viremia na fase inicial da doença por ser secretada na circulação durante a replicação viral, está associada a doença clínica grave que se manifesta como febre hemorrágica da dengue (DHF) ou síndrome do choque da dengue pela indução de interleucina (IL) ‐10 e tem sido estudada além de biomarcador para diagnóstico, como alvo terapêutico. Objetivos: Descrever o uso da proteína não estrutural (NS1) para diagnóstico precoce da dengue e como potencial alvo terapêutico. Material e métodos: Foi realizado uma revisão da literatura, onde os artigos foram consultados nas bases de dados científicos: NCBI e Scielo, com os termos: “Dengue”, “NS1”, “Patogênese”, publicados entre 2014 e 2020. Resultados: Estudos mostram que a NS1 contribui na patogênese da doença, ao interagir com o endotélio e induzir vazamento vascular, uma característica clínica da dengue grave, também ativando o sistema complemento e induzindo citocinas imunossupressoras. Por isso, sua detecção precoce contribui para o diagnóstico/tratamento imediato, prevenindo a evolução para formas mais agressivas da doença. Essa proteína também pode ser utilizada para identificar quais pacientes tem chances de desenvolver febre hemorrágica, pois durante a fase inicial da doença os níveis de NS1 são mais altos. Tem sido recomendada a combinação da detecção do antígeno NS1 na circulação e dos anticorpos anti-NS1 para melhorar a sensibilidade e a especificidade do diagnóstico. Em estudos em camundongos, os anticorpos anti-NS1 podem reduzir a replicação viral de células infectadas, bloquear os efeitos patogênicos desencadeados por NS1 in vitro e em in vivo. Conclusão: É necessário o desenvolvimento de novos testes que aumentem a sensibilidade e especificidade do diagnóstico da NS1 e também tratamentos direcionados à NS1 que podem ser úteis na redução da gravidade da doença.

scholarly journals Translation initiation in Drosophila melanogaster is reduced by mutations upstream of the AUG initiator codon.

1991 ◽  
Vol 11 (4) ◽  
pp. 2149-2153 ◽  
Author(s):  
Y Feng ◽  
L E Gunter ◽  
E L Organ ◽  
D R Cavener
Keyword(s):  
Translation Initiation ◽  
Larval Stage ◽  
Developmental Stages ◽  
Germ Line ◽  
Adult Stage ◽  
Mutant Gene ◽  
Start Codon ◽  
Fold Reduction

The importance to in vivo translation of sequences immediately upstream of the Drosophila alcohol dehydrogenase (Adh) start codon was examined at two developmental stages. Mutations were introduced into the Adh gene in vitro, and the mutant gene was inserted into the genome via germ line transformation. An A-to-T substitution at the -3 position did not affect relative translation rates of the ADH protein at the second-instar larval stage but resulted in a 2.4-fold drop in translation of ADH at the adult stage. A second mutant gene, containing five mutations in the region -1 to -9, was designed to completely block translation initiation. However, transformant lines bearing these mutations still exhibit detectable ADH, albeit at substantially reduced levels. The average fold reduction at the second-instar larval stage was 5.9, while at the adult stage a 12.5-fold reduction was observed.

scholarly journals In vitro and in vivo anthelmintic activity of extracts from Artemisia parviflora and A. sieversiana

2017 ◽  
Vol 54 (3) ◽  
pp. 218-224 ◽  
Author(s):  
S. Irum ◽  
H. Ahmed ◽  
B. Mirza ◽  
K. Donskow-Łysoniewska ◽  
A. Muhammad ◽  
...  
Keyword(s):  
Adult Worm ◽  
Plant Extracts ◽  
Small Ruminants ◽  
Anthelmintic Activity ◽  
Gastrointestinal Nematodes ◽  
Economic Losses ◽  
Egg Hatching ◽  
Infective Larvae

SummaryIn the northern areas of Pakistan, the use of Artemisia based therapeutics is a common practice. Plants of genus Artemisia are known to possess anthelmintic and therapeutic effect. Infections caused by gastrointestinal nematodes are major threat to livestock industry across the world resulting in loss of production and indirect economic losses due to high cost of anthelmintic drugs. Present study was carried out to evaluate in vitro and in vivo effect of Artemisia sieversiana and Artemisia parviflora on Haemonchus contortus, a parasitic nematode of small ruminants. Methanolic plant extract was tested against three different developmental stages using an egg hatch assay, infective larvae and adult worm motility assay. Different concentrations were used for the bioassays and post exposure mortality was recorded after 8 hr for adult worms and infective larvae, while egg inhibition percentage was observed after 27 hr. A highly significant ability to inhibit the egg hatching (100 %) was recorded for both plant extracts while, the highest activity for adult worm assay and larvicidal assay was 90 % for A. sieversiana. The highest activity for adult motility and larvicidal assay for A. parviflora was 89 % and 86.6 % respectively. For in vivo trials maximum parentage reduction was 77.0 % for A. sieversiana and 73.6 % for A. parviflora. It is concluded that selected plant extracts were effective in reducing worm burden in animals.

Sign in / Sign up

Export Citation Format

Share Document