Database : MEDLINE
Search on : D02.675.276.102 [DeCS Category]
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  1 / 132 MEDLINE  
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PMID:26537290
Author:Lisiecki K; Krawczyk KK; Roszkowski P; Maurin JK; Czarnocki Z
Address:Faculty of Chemistry, University of Warsaw, Pasteura 1, Warsaw 02-093, Poland. czarnoz@chem.uw.edu.pl.
Title:Formal synthesis of (-)-podophyllotoxin through the photocyclization of an axially chiral 3,4-bisbenzylidene succinate amide ester--a flow photochemistry approach.
Source:Org Biomol Chem; 14(2):460-469, 2016 Jan 14.
ISSN:1477-0539
Country of publication:England
Language:eng
Abstract:We have developed a strategy for the stereoselective synthesis of cyclolignans related to podophyllotoxin and its derivatives. The crucial step of the synthesis is the photocyclization of a chiral atropoisomeric 1,2-bisbenzylidenesuccinate amide ester, which can be prepared from suitable aromatic aldehydes, diethyl succinate and l-prolinol. The photocyclization was found to be more efficient when irradiation was performed in a home-built continuous flow photochemical reactor. The in-flow irradiation also allowed us to perform the reaction on a multigram scale. The chiral auxiliary was removed by reductive cleavage with the Schwartz's reagent to give the cytotoxic 1R,2R-cis-podophyllic aldehyde, which in turn could be easily reduced to the corresponding alcohol, completing the formal synthesis of (-)-podophyllotoxin.
Publication type:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
Name of substance:0 (3,4-bisbenzylidene succinate amide ester); 0 (Bephenium Compounds); 0 (Succinates); L36H50F353 (Podophyllotoxin)


  2 / 132 MEDLINE  
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PMID:23562945
Author:Robertson AP; Buxton SK; Martin RJ
Address:Department Biomedical Science, College of Veterinary Medicine, Iowa State University, Ames, USA. Electronic address: alanr@iastate.edu.
Title:Whole-cell patch-clamp recording of nicotinic acetylcholine receptors in adult Brugia malayi muscle.
Source:Parasitol Int; 62(6):616-8, 2013 Dec.
ISSN:1873-0329
Country of publication:Netherlands
Language:eng
Abstract:Lymphatic filariasis is a debilitating disease caused by clade III parasites like Brugia malayi and Wuchereria bancrofti. Current recommended treatment regimen for this disease relies on albendazole, ivermectin and diethylcarbamazine, none of which targets the nicotinic acetylcholine receptors in these parasitic nematodes. Our aim therefore has been to develop adult B. malayi for electrophysiological recordings to aid in characterizing the ion channels in this parasite as anthelmintic target sites. In that regard, we recently demonstrated the amenability of adult B. malayi to patch-clamp recordings and presented results on the single-channel properties of nAChR in this nematode. We have built on this by recording whole-cell nAChR currents from adult B. malayi muscle. Acetylcholine, levamisole, pyrantel, bephenium and tribendimidine activated the receptors on B. malayi muscle, producing robust currents ranging from >200 pA to ~1.5 nA. Levamisole completely inhibited motility of the adult B. malayi within 10 min and after 60 min, motility had recovered back to control values.
Publication type:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL
Name of substance:0 (Anthelmintics); 0 (Bephenium Compounds); 0 (Ion Channels); 0 (Nicotinic Agonists); 0 (Phenylenediamines); 0 (Receptors, Nicotinic); 115103-15-6 (tribendimidine); 2880D3468G (Levamisole); 4QIH0N49E7 (Pyrantel); N9YNS0M02X (Acetylcholine)


  3 / 132 MEDLINE  
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PMID:22526556
Author:Charvet CL; Robertson AP; Cabaret J; Martin RJ; Neveu C
Address:INRA, UMR1282 Infectiologie et Santé Publique, Centre de Recherches de Tours, 37380 Nouzilly, France. claude.charvet@tours.inra.fr
Title:Selective effect of the anthelmintic bephenium on Haemonchus contortus levamisole-sensitive acetylcholine receptors.
Source:Invert Neurosci; 12(1):43-51, 2012 Jun.
ISSN:1439-1104
Country of publication:Germany
Language:eng
Abstract:Acetylcholine receptors (AChRs) are pentameric ligand-gated ion channels involved in the neurotransmission of both vertebrates and invertebrates. A number of anthelmintic compounds like levamisole and pyrantel target the AChRs of nematodes producing spastic paralysis of the worms. The muscle AChRs of nematode parasites fall into three pharmacological classes that are preferentially activated by the cholinergic agonists levamisole (L-type), nicotine (N-type) and bephenium (B-type), respectively. Despite a number of studies of the B-type AChR in parasitic species, this receptor remains to be characterized at the molecular level. Recently, we have reconstituted and functionally characterized two distinct L-AChR subtypes of the gastro-intestinal parasitic nematode Haemonchus contortus in the Xenopus laevis oocyte expression system by providing the cRNAs encoding the receptor subunits and three ancillary proteins (Boulin et al. in Br J Pharmacol 164(5):1421-1432, 2011). In the present study, the effect of the bephenium drug on Hco-L-AChR1 and Hco-L-AChR2 subtypes was examined using the two-microelectrode voltage-clamp technique. We demonstrate that bephenium selectively activates the Hco-L-AChR1 subtype made of Hco-UNC-29.1, Hco-UNC-38, Hco-UNC-63, Hco-ACR-8 subunits that is more sensitive to levamisole than acetylcholine. Removing the Hco-ACR-8 subunit produced the Hco-L-AChR2 subtype that is more sensitive to pyrantel than acetylcholine and partially activated by levamisole, but which was bephenium-insensitive indicating that the bephenium-binding site involves Hco-ACR-8. Attempts were made to modify the subunit stoichiometry of the Hco-L-AChR1 subtype by injecting five fold more cRNA of individual subunits. Increased Hco-unc-29.1 cRNA produced no functional receptor. Increasing Hco-unc-63, Hco-unc-38 or Hco-acr-8 cRNAs did not affect the pharmacological characteristics of Hco-L-AChR1 but reduced the currents elicited by acetylcholine and the other agonists. Here, we provide the first description of the molecular composition and functional characteristics of any invertebrate bephenium-sensitive receptor.
Publication type:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T
Name of substance:0 (Anthelmintics); 0 (Bephenium Compounds); 0 (Helminth Proteins); 0 (Receptors, Cholinergic); 2880D3468G (Levamisole)


  4 / 132 MEDLINE  
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PMID:18710918
Author:Kopp SR; Coleman GT; McCarthy JS; Kotze AC
Address:School of Veterinary Science, University of Queensland, Brisbane, Australia.
Title:Phenotypic characterization of two Ancylostoma caninum isolates with different susceptibilities to the anthelmintic pyrantel.
Source:Antimicrob Agents Chemother; 52(11):3980-6, 2008 Nov.
ISSN:1098-6596
Country of publication:United States
Language:eng
Abstract:The anthelmintic pyrantel plays an important role in the control of gastrointestinal helminths of humans and domestic animals. Despite the demonstration of pyrantel resistance in several helminth species over the last 20 years, the resistance mechanism remains unclear. It has been hypothesized that resistance may arise as a consequence of changes to the relative proportions of subpopulations of nicotinic acetylcholine receptors (nAchRs). To test this hypothesis, we examined the responses of two isolates of the canine hookworm Ancylostoma caninum with low-level resistance (isolate NT) and high-level resistance (isolate PR) to pyrantel to nicotinic agonist drugs reported to be selective for three nAchR subtypes. We used larval motility and conformation assays and force transduction experiments with adult worms. Pyrantel and levamisole were less potent against larvae of isolate PR than larvae of isolate NT (up to an 18-fold increase in the 50% inhibitory concentration); on the other hand, bephenium was more potent against larvae of isolate PR than larvae of isolate NT (twofold) and nicotine had the same potency against larvae of both isolates. In adults, pyrantel, levamisole, and nicotine were less potent against isolate PR than isolate NT (two- to threefold), but the potency of bephenium against the two isolates was equivalent. Our data indicate a complex pattern of nAchRs in this species and suggest that the two isolates differ in their relative sensitivities to agonists targeting different nAchRs.
Publication type:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
Name of substance:0 (Antinematodal Agents); 0 (Bephenium Compounds); 0 (Nicotinic Agonists); 0 (Receptors, Nicotinic); 2880D3468G (Levamisole); 4QIH0N49E7 (Pyrantel); 6M3C89ZY6R (Nicotine)


  5 / 132 MEDLINE  
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PMID:17056760
Author:Qian H; Martin RJ; Robertson AP
Address:Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, Iowa 50011-1250, USA.
Title:Pharmacology of N-, L-, and B-subtypes of nematode nAChR resolved at the single-channel level in Ascaris suum.
Source:FASEB J; 20(14):2606-8, 2006 Dec.
ISSN:1530-6860
Country of publication:United States
Language:eng
Abstract:Pharmacological experiments on Ascaris suum have demonstrated the presence of three (N-, L-, and B-) subtypes of cholinergic receptor mediating contraction of body wall muscle in parasitic nematodes. In the present study, these ionotropic acetylcholine (ACh) receptors (nAChRs) were activated by levamisole and bephenium under patch-clamp conditions and competitively antagonized by paraherquamide and 2-desoxoparaherquamide. A number of recordings exhibited three separate current amplitude levels, indicating the presence of small, intermediate, and large conductance subtypes of receptor. The mean conductance of the small conductance subtype, G25, was 22 +/- 1 pS; the intermediate conductance channel, G35, was 33 +/- 1 pS; and the large conductance channel, G45, was 45 +/- 1 pS. The small channel was not antagonized significantly by paraherquamide and was identified as the N-subtype. The intermediate channel was preferentially activated by levamisole rather than bephenium and antagonized by paraherquamide: the intermediate channel was identified as the L-subtype. The large conductance channel was preferentially activated by bephenium, antagonized more by 2-desoxoparaherquamde than by paraherquamide and was identified as the B-subtype. These observations reveal that the three channel subtypes have different selectivity for cholinergic anthelmintics. The different selectivity of these compounds should be considered when dealing with drug resistant infections.
Publication type:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL
Name of substance:0 (2-desoxoparaherquamide A); 0 (Anthelmintics); 0 (Bephenium Compounds); 0 (Indolizines); 0 (Pyridines); 0 (Receptors, Cholinergic); 0 (Spiro Compounds); 114-91-0 (methyridine); 2880D3468G (Levamisole); R72VB4E4KC (paraherquamide)


  6 / 132 MEDLINE  
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PMID:15610819
Author:Trailovic SM; Clark CL; Robertson AP; Martin RJ
Address:Department of Biomedical Sciences, Iowa State University, Ames, IA 50010, USA.
Title:Brief application of AF2 produces long lasting potentiation of nAChR responses in Ascaris suum.
Source:Mol Biochem Parasitol; 139(1):51-64, 2005 Jan.
ISSN:0166-6851
Country of publication:Netherlands
Language:eng
Abstract:Resistance of parasitic nematodes to the cholinergic anthelmintic levamisole is associated with a reduction in the proportion of time that acetylcholine receptor ion-channels are in the open state decreasing the response of nematode parasites to the drug. Here we examine electrophysiological and contractile responses to acetylcholine and the cholinergic agonist, levamisole, in Ascaris suum muscle looking for a pharmacological approach that may be developed to increase the response to cholinergic agonists. We found that short application of the FMRFamide, AF2, produced modulation (long lasting potentiation) of the peak membrane potential response to acetylcholine but not to levamisole. Since levamisole preferentially activates L-type acetylcholine receptors, we also tested the effect of nicotine (selective activator of N-type acetylcholine receptors) and bephenium (selective activator of B-type acetylcholine receptors) and found again no effect of AF2 on peak membrane potential responses. We then tested atropine on the AF2 potentiation of acetylcholine and found it to inhibit the peak potentiation suggesting that AF2 receptors interact with muscarinic receptors to produce the potentiation of acetylcholine. We saw similar atropine sensitive potentiation of acetylcholine responses in our muscle contraction experiments. The potentiation of the acetylcholine responses shows that nematode acetylcholine receptors are capable of a level of plasticity. A model involving calcium release from the sarcoplasmic reticulum, CaM Kinase, calcineurin, muscarinic receptors and AF2 receptors is proposed to explain our observations. These observations are important because they point to a pharmacological approach that may be developed to counter resistance to cholinergic anthelmintics.
Publication type:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, U.S. GOV'T, P.H.S.
Name of substance:0 (Antinematodal Agents); 0 (Bephenium Compounds); 0 (Receptors, Muscarinic); 0 (Receptors, Nicotinic); 054NR2135Y (Furylfuramide); 2880D3468G (Levamisole); 6M3C89ZY6R (Nicotine); 7C0697DR9I (Atropine); EC 2.7.11.17 (Calcium-Calmodulin-Dependent Protein Kinases); N9YNS0M02X (Acetylcholine); SY7Q814VUP (Calcium)


  7 / 132 MEDLINE  
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PMID:14581174
Author:Martin RJ; Bai G; Clark CL; Robertson AP
Address:Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, IA 50010, USA. rjmartin@iastate.edu
Title:Methyridine (2-[2-methoxyethyl]-pyridine]) and levamisole activate different ACh receptor subtypes in nematode parasites: a new lead for levamisole-resistance.
Source:Br J Pharmacol; 140(6):1068-76, 2003 Nov.
ISSN:0007-1188
Country of publication:England
Language:eng
Abstract:1. The development of resistance to all chemotherapeutic agents increases and needs to be addressed. We are interested in resistance in parasitic nematodes to the anthelmintic levamisole. During studies on methyridine, we found that it gave us a new insight into pharmacological changes associated with levamisole resistance. Initially, electrophysiological investigation using a two-micropipette current-clamp recording technique revealed that methyridine acts as a cholinergic agonist on nematode muscle receptors (Ascaris suum). Methyridine (>30 microm) produced reversible concentration-dependent depolarizations and increases in input conductance. Mecamylamine (30 microm) and paraherquamide (0.3 microm) produced reversible antagonism of the depolarization and conductance responses to methyridine. These observations suggest that methyridine, like acetylcholine and levamisole, gates ion channels on the muscle of parasitic nematodes. 2. The antagonistic effects of dihydro-beta-erythroidine and paraherquamide on methyridine-induced contractions of A. suum muscle flaps were then examined to determine if methyridine showed subtype selectivity for N-subtype (nicotine-sensitive) or L-subtype (levamisole-sensitive) acetylcholine receptors. Dihydro-beta-erythroidine weakly antagonized the effects of methyridine (but had no effect on levamisole responses). The antagonism of methyridine (pA2, 5.9) and nicotine (pA2, 6.1) by paraherquamide was similar, but was less than the antagonism of levamisole (pA2, 7.0). The antagonist profiles suggested that methyridine has a selective action on the N-subtype rather than on the L-subtype. 3. A novel use for a larval inhibition migration assay was made using L3 larvae of Oesophagostomum dentatum. Inhibitory effects of nicotine, levamisole, pyrantel and methyridine on the migration of larvae of levamisole-sensitive (SENS) and levamisole-resistant (LEV-R) isolates were tested at different concentrations. Levamisole and pyrantel (putative L-subtype-selective agonists) concentration-response plots were displaced to the right in LEV-R isolates. Nicotine (an N-subtype-selective agonist) and methyridine produced little shift in concentration-response plots in the LEV-R isolates. Resistance dose ratios were used to calculate the relative selectivity, rhoL, for the L-type receptor (levamisole rhoL=1.0; pyrantel rhoL=0.93; methyridine rhoL=0.17; nicotine rhoL=0.06). These observations reveal an N-subtype-selective action of methyridine and suggest that levamisole resistance may be associated with a loss of the L-subtype, but not the N-subtype receptors. The pharmacology of methyridine suggests an approach for the treatment of levamisole-resistant parasites.
Publication type:COMPARATIVE STUDY; JOURNAL ARTICLE; RESEARCH SUPPORT, U.S. GOV'T, P.H.S.
Name of substance:0 (Antinematodal Agents); 0 (Bephenium Compounds); 0 (Indolizines); 0 (Nicotinic Antagonists); 0 (Protein Isoforms); 0 (Pyridines); 0 (Receptors, Nicotinic); 0 (Spiro Compounds); 114-91-0 (methyridine); 23255-54-1 (Dihydro-beta-Erythroidine); 2880D3468G (Levamisole); 4QIH0N49E7 (Pyrantel); 6EE945D3OK (Mecamylamine); 6M3C89ZY6R (Nicotine); R72VB4E4KC (paraherquamide)


  8 / 132 MEDLINE  
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PMID:8168249
Author:Tang CM; Huang JJ
Address:Institute of Parasitic Diseases Control, Guangxi Zhuang Autonomous Region, Nanning.
Title:[Field studies on different control schemes for hookworm infection].
Source:Zhongguo Ji Sheng Chong Xue Yu Ji Sheng Chong Bing Za Zhi; 11(3):219-23, 1993.
ISSN:1000-7423
Country of publication:China
Language:chi
Abstract:Three different control schemes including selective chemotherapy, a combination of selective chemotherapy and management of fecal disposal and mass treatment with mebendazole-medicated salt were implemented for the control of hookworm infection in Luwo Town and Taiping Village, Wuming County, Guangxi Zhuang Autonomous Region during 1971-1990. Through ten years of selective chemotherapy, the results showed that the hookworm infection rate dropped from 42.6% to 3.9% and the infection intensity from 425.6 eggs per gram faeces to 1.6 eggs per gram faeces. After seven years of selective chemotherapy combined with management of fecal, the hookworm infection rate dropped from 58.7% to 10.9% and the infection intensity from 111.5 eggs per gram faeces to 8.5 eggs per gram faeces. However, 3 years after the termination of the combined treatment, the hookworm infection rate increased to 14.5%. As for the implementation of the third scheme, mebendazole-medicated salt was given at 100 mg daily for 30 consecutive days or at 50 mg daily for 30 consecutive days. Stool examination was made one year after the treatment, the results showed that the infection rate of the inhabitants dropped from 36% and 36% to 2% and 1.3%, respectively, and the infection intensity dropped from 110.3 and 246 eggs per gram faeces to 1.3 and 0.24 eggs per gram faeces. After three years, the infection rate of inhabitants remained under 2% and the infection intensity under 1 egg per gram faeces. It was concluded that mass treatment with mebendazole-medicated salt might be the most practical scheme for the control of hookworm infection.
Publication type:COMPARATIVE STUDY; ENGLISH ABSTRACT; JOURNAL ARTICLE
Name of substance:0 (Bephenium Compounds); 2880D3468G (Levamisole); 81BK194Z5M (Pyrantel Pamoate); 81G6I5V05I (Mebendazole)


  9 / 132 MEDLINE  
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PMID:1758363
Author:Blagov NA; Miagkova MA; Firsov VN; Zhuravleva TB; Petrova IV
Title:Morfologicheskie izmeneniia slizistoi obolochki zheludka i tonkoi kishki krys pod deistviem mebendazola. [Morphological changes in the mucosa of the stomach and the small intestine of rats under the action of mebendazole].
Source:Med Parazitol (Mosk); (5):41-4, 1991 Sep-Oct.
ISSN:0025-8326
Country of publication:Russia (Federation)
Language:rus
Abstract:The effect of mebendazole on the gastric and intestinal mucosa was studied in 52 intact white rats. It was shown that the drug caused a significant damage to the mucosa, especially of goblet cells of villi and crypts and interfere with the mucoid secretion. The alterations after mebendazole administration were more severe than those caused by naphthamon. On the 13-15th day after the treatment the complete restoration of the damage was not seen.
Publication type:COMPARATIVE STUDY; ENGLISH ABSTRACT; JOURNAL ARTICLE
Name of substance:0 (Anthelmintics); 0 (Bephenium Compounds); 47RU9546DX (bephenium hydroxynaphthoate); 81G6I5V05I (Mebendazole)


  10 / 132 MEDLINE  
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PMID:2779491
Author:Blagov NA; Firsov VN
Title:Mikroparazitotsenoz kishechnika i aktivnost' kishechnykh fermentov u bol'nykh trikhotsefalezom v protsesse lecheniia. [Microparasitocenosis of the intestines and the activity of intestinal enzymes in patients with trichocephaliasis during treatment].
Source:Med Parazitol (Mosk); (3):49-53, 1989 May-Jun.
ISSN:0025-8326
Country of publication:Russia (Federation)
Language:rus
Abstract:Results of the studies of large intestine microflora, enterokinase and alkaline phosphatase activity in the feces of 298 children and adults suffering from trichocephaliasis are presented. Intestinal dysbacteriosis was observed in 51.7% cases, increased enterokinase activity, in 57.6% cases and increased alkaline phosphatase activity, in 55% cases. Enteric enzyme activity relation to the state of enteric microflora is demonstrated. Specific bephenium hydroxynaphthoate and mebendazole treatment was followed by increased dysbacteriosis and higher intestinal enzyme activity, especially in case of bephenium hydroxynaphthoate treatment. Normalization of the above-mentioned parameters was observed 90-120 days after the end of the treatment.
Publication type:COMPARATIVE STUDY; ENGLISH ABSTRACT; JOURNAL ARTICLE
Name of substance:0 (Anthelmintics); 0 (Bephenium Compounds); 47RU9546DX (bephenium hydroxynaphthoate); 81G6I5V05I (Mebendazole); EC 3.1.3.1 (Alkaline Phosphatase); EC 3.4.21.9 (Enteropeptidase)



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