African trypanosomatid parasites escape host acquired immune responses through periodic antigenic variation of their surface coat.In this study,we describe a mechanism by which the parasites counteract innate immune r...African trypanosomatid parasites escape host acquired immune responses through periodic antigenic variation of their surface coat.In this study,we describe a mechanism by which the parasites counteract innate immune responses.Two Tat D DNases were identified in each of Trypanosoma evansi and Trypanosoma brucei.These DNases are bivalent metal-dependent endonucleases localized in the cytoplasm and flagella of the parasites that can also be secreted by the parasites.These enzymes possess conserved functional domains and have efficient DNA hydrolysis activity.Host neutrophil extracellular traps(NETs)induced by the parasites could be hydrolyzed by native and recombinant Tat D DNases.NET disruption was prevented,and the survival rate of parasites was decreased,in the presence of the DNase inhibitor aurintricarboxylic acid.These data suggest that trypanosomes can counteract host innate immune responses by active secretion of Tat D DNases to degrade NETs.展开更多
Objective:To determine the presence of Trypanosoma eransi(T.evansi) and the effect of trypanosomosis on hemato-biochemical profile of dromedary camels in Semnan,Iran,which has not been reported yet.Methods:To perform ...Objective:To determine the presence of Trypanosoma eransi(T.evansi) and the effect of trypanosomosis on hemato-biochemical profile of dromedary camels in Semnan,Iran,which has not been reported yet.Methods:To perform this project,blood samples were collected by venipuncture into plain and EDTA-K2-containing vacutainer tubes from 21 dromedary camels(12 males and 9 females) aged3—18 years,from 4 different regions of Semnan.Results:Microscopic examination of stained thin blood smears revealed the presence of T.evansi in one of the samples.However,it should be noted that this sample showed a very high parasitemia(more than 5 trypomastigote were visible per microscopic field with MGG,1000×.This heavy parasitemia was associated with an 18-year-old female camel that showed symptoms of corneal opacity,intense emaciation and pale mucous membranes.Comparison of hematological and serum biochemical profiles between the camel infected by T.eransi and uninfected camels indicated anemia,leukocytosis,hyperproteinemia.hypoalbuminemia,hyperglobulinemia,reduction A/G ratio,increased a,,p and globulins and decreased of a,globulins and increased the concentration of gumma-glutamyl transferase enzyme.Conclusions:Results of the present study revealed that trypanosomosis was present in dromedary camels of Semnan,Iran(infection rate is 4.76%) and hemato-biochemical parameters were markedly affected by camel trypanosomosis.展开更多
Objective:To examine thein vitroandin vivoanti-Trypanosoma evansi(T.evansi)activity ofsaponins-rich fraction ofCalotropis procera(cpsf)leaves as well as the effect of the fraction onthe parasite-induced anemia.Methods...Objective:To examine thein vitroandin vivoanti-Trypanosoma evansi(T.evansi)activity ofsaponins-rich fraction ofCalotropis procera(cpsf)leaves as well as the effect of the fraction onthe parasite-induced anemia.Methods:A 60-minutes time course experiment was conductedwith various concentrations of the fraction using a 96-well microtiter plate technique,andsubsequently used to treat experimentallyT.evansiinfected rats at 100 and 200 mg/kg bodyweight.Index of anemia was analyzed in all animals during the experiment.Results:The cpsfdid not demonstrate anin vitroantitrypanosomal activity.Further,the cpsf treatments did notsignificantly(P>0.05)keep the parasites lower than the infected untreated groups.At the end ofthe experiment,allT.evansiinfected rats developed anemia whose severity was not significantly(P>0.05)ameliorated by the cpsf treatment.Conclusions:It was concluded that saponins derivedfromCalotropis proceraleaves could not elicitin vitroandin vivoactivities againstT.evansi.展开更多
Objective:To evaluate activity of methanol extract of Achillea fragrantissima(meth)(A.fragrantissima) alone or in combination with diminazine aceturate(DA) against Trypanosoma evansi in experimentally infected rats.Me...Objective:To evaluate activity of methanol extract of Achillea fragrantissima(meth)(A.fragrantissima) alone or in combination with diminazine aceturate(DA) against Trypanosoma evansi in experimentally infected rats.Methods:Sixty adult male Wister albino rats were divided equally into 6 groups(A-F).Rats in groups A-E were experimentally infected with T.evansi and those in group F were uninfected.The groups were treated respectively as follows:group A- with 3.5 mg/kg DA;group B- with 1 000 mg/kg meth,A.fragrantissima;group C-3.5mg/kg DA plus 500 mg/kg meth A.fragrantissima;group D-3.5 mg/kg DA plus 1 000 mg/kg meth A.fragrantissima.Group E was left untreated.Parasitaemia,survivability,packed cell volume,hemoglobin concentration,total leucocytes count,lymphocyte count,and serum malondialdehyde and reduced glutathione(GSH) levels were estimated.Phytochemical screening of meth A.fragrantissima was also performed.Results:The phytochemical analysis of the meth A.fragrantissima indicated a higher content from polyphenols tannins and non tannins and flavonoids.The efficacy percentage against trypanosomiasis in groups A to E was respectively as follows 80,40,90.100,0.The administration of meth-A.fragrantissima(1000)mg/kg b.wt.) produced a moderate efficacy against trypanosomiasis.Untreated rats in group E died between 25 and 30 d post infection.The rats given DA and meth A.fragrantissima combinations(C and D) showed faster and higher recovery rates than the uninfected control and groups A and B.The initial reduction in packed cell volume,hemoglobin,total leucocytes count,increases in serum malondialdehyde and decreases in GSH levels were reversed by the treatments.C onclusions:The administration of the methanol extracts of A.fragrantissima and DA combination therapy was more effective than each product alone in the treatment of rats infected with Trypanosoma evansi and further studies are required to isolate more active ingredients.展开更多
Trypanosoma evansi, an economically important haemoflagellate, infects many domestic and wild animals such as horses, camels, buffalo and deer, causing the trypanosomiasis called surra in these animals. This parasite ...Trypanosoma evansi, an economically important haemoflagellate, infects many domestic and wild animals such as horses, camels, buffalo and deer, causing the trypanosomiasis called surra in these animals. This parasite has an extremely wide geographical distribution in the continents of Asia, Africa and South America. Surra is also one of the most important endemic diseases of animals in China, especially展开更多
Spider mites(Tetranychidae)are destructive agricultural pests which have evolved strategies to overcome plant defenses,such as the ability to puncture the leaves of their hosts to feed.The expression of many genes wit...Spider mites(Tetranychidae)are destructive agricultural pests which have evolved strategies to overcome plant defenses,such as the ability to puncture the leaves of their hosts to feed.The expression of many genes with unknown functions is altered during feeding,but little is known about the role of these genes in plant–mite interactions.Here,we identified 3 novel gene families through analysis of genomic and transcriptomic data from 3 spider mite species.These GARP family genes encode glycine and alanine-rich proteins;they are present in mites(Acariformes)but absent in ticks(Parasitiformes)in the subclass Acari,indicating that these genes have undergone a significant expansion in spider mites and thus play important adaptive roles.Transcriptomic analysis revealed that the expression of GARP genes is strongly correlated with feeding and the transfer to new hosts.We used RNA interference to silence GARP1d in the two-spotted spider mite Tetranychus urticae,which inhibited feeding and egg laying and significantly increased mortality when the mites were transferred to soybean shoots;a similar effect was observed after TuVATPase was silenced.However,no changes in mite mortality were observed after TuGARP1d-silenced mites were placed on an artificial diet,which was different from the effect of TuVATPase silencing.Our results indicate that GARP family members play important roles in mite–plant interactions.Additional studies are needed to clarify the mechanisms underlying these interactions.展开更多
Emblica officinalis （E. oJficinalis） dried fruits were evaluated for its antitrypanosomal activity and cytotoxic effects. Vero cell line maintained in DMEM （Dubecco＇s Modified Eagle Medium） and incubated with Try...Emblica officinalis （E. oJficinalis） dried fruits were evaluated for its antitrypanosomal activity and cytotoxic effects. Vero cell line maintained in DMEM （Dubecco＇s Modified Eagle Medium） and incubated with Trypanosoma evansi for more than 12 h. MPE was added to the Vero cell culture medium at different concentrations （250-1,000 μg/mL） with trypanosomes concentration （1 × 106 trypanosomes/mL in each ELISA plate well） and incubated at appropriate conditions for 72 h. In-vitro cytotoxieity of MPE of E. officinalis was determined on Vero cells at concentrations （（1.56-100 ~tg/mL）. Acute toxicity and in-vivo infectivity tests were done in mice. Obtained MPE ofE. officinalis underwent process of purification via column chromatography, preparative chromatography and HPLC （higher performance liquid chromatography） with bioassay at different strata on Alsever＇s medium. In-vivo assay for trypanocidal activity, MPE and PPFs （partially purified fractions） of E. officinalis with two sets of mice, each mouse was inoculated with 1 × 104/mL oftrypanosomes and treated （48 h post inoculation） at concentrations （12.5, 25, 50, 100 and 200 mg/kg body weight） were administered at dose rate of 100 [tL per mouse via intraperitoneal route （in treating parassitemic mice） to different groups of mice, 6 mice per concentration. HPLC of partially purified fractions ofE. officinalis was carried out with mobile phase ofacetonitdle： water （40：60） in gradient mode. In vitro, MPE induced immobilization and killing of the parasites in concentration-time dependent manner. Significant reduction of trypanosomes counts from concentration of 250μg/mL and complete killing of trypanosomes at 5th hour of observation, which was statistically equivalent to 4th hour of Diminazine Aceturate （Berenil）, standard reference drug used. HPLC of the partially purified fractions revealed two major prominent peaks at retention time of 1-4 min. In vivo, both MPE and PPFs of test material did prolong lives 展开更多
It is well known that herbivore-induced plant defenses alter host plant quality and can affect the behavior and performance of later arriving herbivores.Effects of sequential attacks by herbivores that either suppress...It is well known that herbivore-induced plant defenses alter host plant quality and can affect the behavior and performance of later arriving herbivores.Effects of sequential attacks by herbivores that either suppress or induce plant defenses are less well studied.We sequentially infested leaves of tomato plants with a strain of the phytophagous spider mite Tetranychus urticae that induces plant defenses and the closely related Tetranychus evansi, which suppresses plant defenses.Plant quality was quantified through oviposifion of both spider mite species and by measuring proteinase inhibitor activity using plant material that had been sequentially attacked by both herbivore species.Spider-mite oviposifion data show that T.evansi could suppress an earlier induction of plant defenses by T.urticae,and T.urticae could induce defenses in plants previously attacked by T.evansi in 1 day.Longer attacks by the second species did not result in further changes in oviposifion.Proteinase inhibitor activity levels showed that T.evansi suppressed the high activity levels induced by T.urticae to constitutive levels in 1 day,and further suppressed activity to levels similar to those in plants attacked by T.evansi alone.Attacks by T.urticae induced proteinase inhibitor activity in plants previously attacked by T.evansi,eventually to similar levels as induced by T.urticae alone.Hence,plant quality and plant defenses were significantly affected by sequential attacks and the order of attack does not affect subsequent performance,but does affect proteinase inhibitor activity levels.Based on our results,we discuss the evolution of suppression of plant defenses.展开更多
基金supported by the Distinguished Scientist grant from Shenyang Agricultural University and Liaoning Province(8804880416076)Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences(CIFMS)(2019-I2M-5-042)。
文摘African trypanosomatid parasites escape host acquired immune responses through periodic antigenic variation of their surface coat.In this study,we describe a mechanism by which the parasites counteract innate immune responses.Two Tat D DNases were identified in each of Trypanosoma evansi and Trypanosoma brucei.These DNases are bivalent metal-dependent endonucleases localized in the cytoplasm and flagella of the parasites that can also be secreted by the parasites.These enzymes possess conserved functional domains and have efficient DNA hydrolysis activity.Host neutrophil extracellular traps(NETs)induced by the parasites could be hydrolyzed by native and recombinant Tat D DNases.NET disruption was prevented,and the survival rate of parasites was decreased,in the presence of the DNase inhibitor aurintricarboxylic acid.These data suggest that trypanosomes can counteract host innate immune responses by active secretion of Tat D DNases to degrade NETs.
基金Supported by research fund of Semnan University.Semnan.Iran(Grant No.266/92/3040)
文摘Objective:To determine the presence of Trypanosoma eransi(T.evansi) and the effect of trypanosomosis on hemato-biochemical profile of dromedary camels in Semnan,Iran,which has not been reported yet.Methods:To perform this project,blood samples were collected by venipuncture into plain and EDTA-K2-containing vacutainer tubes from 21 dromedary camels(12 males and 9 females) aged3—18 years,from 4 different regions of Semnan.Results:Microscopic examination of stained thin blood smears revealed the presence of T.evansi in one of the samples.However,it should be noted that this sample showed a very high parasitemia(more than 5 trypomastigote were visible per microscopic field with MGG,1000×.This heavy parasitemia was associated with an 18-year-old female camel that showed symptoms of corneal opacity,intense emaciation and pale mucous membranes.Comparison of hematological and serum biochemical profiles between the camel infected by T.eransi and uninfected camels indicated anemia,leukocytosis,hyperproteinemia.hypoalbuminemia,hyperglobulinemia,reduction A/G ratio,increased a,,p and globulins and decreased of a,globulins and increased the concentration of gumma-glutamyl transferase enzyme.Conclusions:Results of the present study revealed that trypanosomosis was present in dromedary camels of Semnan,Iran(infection rate is 4.76%) and hemato-biochemical parameters were markedly affected by camel trypanosomosis.
基金This study was supported,in part,by the Education Trust FundABU desk office with reference ETF/DESS/AST&D/ABU ZARIA
文摘Objective:To examine thein vitroandin vivoanti-Trypanosoma evansi(T.evansi)activity ofsaponins-rich fraction ofCalotropis procera(cpsf)leaves as well as the effect of the fraction onthe parasite-induced anemia.Methods:A 60-minutes time course experiment was conductedwith various concentrations of the fraction using a 96-well microtiter plate technique,andsubsequently used to treat experimentallyT.evansiinfected rats at 100 and 200 mg/kg bodyweight.Index of anemia was analyzed in all animals during the experiment.Results:The cpsfdid not demonstrate anin vitroantitrypanosomal activity.Further,the cpsf treatments did notsignificantly(P>0.05)keep the parasites lower than the infected untreated groups.At the end ofthe experiment,allT.evansiinfected rats developed anemia whose severity was not significantly(P>0.05)ameliorated by the cpsf treatment.Conclusions:It was concluded that saponins derivedfromCalotropis proceraleaves could not elicitin vitroandin vivoactivities againstT.evansi.
基金This project(No.BCS06)was financiully supported by Promising Research Center in Biological Control and Agricultural Information(BCARC).Qassim University,Al Qassim.Kingdom of Saudi Arabia
文摘Objective:To evaluate activity of methanol extract of Achillea fragrantissima(meth)(A.fragrantissima) alone or in combination with diminazine aceturate(DA) against Trypanosoma evansi in experimentally infected rats.Methods:Sixty adult male Wister albino rats were divided equally into 6 groups(A-F).Rats in groups A-E were experimentally infected with T.evansi and those in group F were uninfected.The groups were treated respectively as follows:group A- with 3.5 mg/kg DA;group B- with 1 000 mg/kg meth,A.fragrantissima;group C-3.5mg/kg DA plus 500 mg/kg meth A.fragrantissima;group D-3.5 mg/kg DA plus 1 000 mg/kg meth A.fragrantissima.Group E was left untreated.Parasitaemia,survivability,packed cell volume,hemoglobin concentration,total leucocytes count,lymphocyte count,and serum malondialdehyde and reduced glutathione(GSH) levels were estimated.Phytochemical screening of meth A.fragrantissima was also performed.Results:The phytochemical analysis of the meth A.fragrantissima indicated a higher content from polyphenols tannins and non tannins and flavonoids.The efficacy percentage against trypanosomiasis in groups A to E was respectively as follows 80,40,90.100,0.The administration of meth-A.fragrantissima(1000)mg/kg b.wt.) produced a moderate efficacy against trypanosomiasis.Untreated rats in group E died between 25 and 30 d post infection.The rats given DA and meth A.fragrantissima combinations(C and D) showed faster and higher recovery rates than the uninfected control and groups A and B.The initial reduction in packed cell volume,hemoglobin,total leucocytes count,increases in serum malondialdehyde and decreases in GSH levels were reversed by the treatments.C onclusions:The administration of the methanol extracts of A.fragrantissima and DA combination therapy was more effective than each product alone in the treatment of rats infected with Trypanosoma evansi and further studies are required to isolate more active ingredients.
基金Project supported by the National Education Committee of P. R. China
文摘Trypanosoma evansi, an economically important haemoflagellate, infects many domestic and wild animals such as horses, camels, buffalo and deer, causing the trypanosomiasis called surra in these animals. This parasite has an extremely wide geographical distribution in the continents of Asia, Africa and South America. Surra is also one of the most important endemic diseases of animals in China, especially
基金supported by the National Natural Science Foundation of China(32272525)the Chongqing Talent Program(cstc2022ycjh-bgzxm0008)+1 种基金the China Agriculture Research System(CARS-26)[Correction added on 27 Feb 2023,after first online publication:The funding number for National Natural Science Foundation of China has been changed from 322725535to32272525.]。
文摘Spider mites(Tetranychidae)are destructive agricultural pests which have evolved strategies to overcome plant defenses,such as the ability to puncture the leaves of their hosts to feed.The expression of many genes with unknown functions is altered during feeding,but little is known about the role of these genes in plant–mite interactions.Here,we identified 3 novel gene families through analysis of genomic and transcriptomic data from 3 spider mite species.These GARP family genes encode glycine and alanine-rich proteins;they are present in mites(Acariformes)but absent in ticks(Parasitiformes)in the subclass Acari,indicating that these genes have undergone a significant expansion in spider mites and thus play important adaptive roles.Transcriptomic analysis revealed that the expression of GARP genes is strongly correlated with feeding and the transfer to new hosts.We used RNA interference to silence GARP1d in the two-spotted spider mite Tetranychus urticae,which inhibited feeding and egg laying and significantly increased mortality when the mites were transferred to soybean shoots;a similar effect was observed after TuVATPase was silenced.However,no changes in mite mortality were observed after TuGARP1d-silenced mites were placed on an artificial diet,which was different from the effect of TuVATPase silencing.Our results indicate that GARP family members play important roles in mite–plant interactions.Additional studies are needed to clarify the mechanisms underlying these interactions.
文摘Emblica officinalis （E. oJficinalis） dried fruits were evaluated for its antitrypanosomal activity and cytotoxic effects. Vero cell line maintained in DMEM （Dubecco＇s Modified Eagle Medium） and incubated with Trypanosoma evansi for more than 12 h. MPE was added to the Vero cell culture medium at different concentrations （250-1,000 μg/mL） with trypanosomes concentration （1 × 106 trypanosomes/mL in each ELISA plate well） and incubated at appropriate conditions for 72 h. In-vitro cytotoxieity of MPE of E. officinalis was determined on Vero cells at concentrations （（1.56-100 ~tg/mL）. Acute toxicity and in-vivo infectivity tests were done in mice. Obtained MPE ofE. officinalis underwent process of purification via column chromatography, preparative chromatography and HPLC （higher performance liquid chromatography） with bioassay at different strata on Alsever＇s medium. In-vivo assay for trypanocidal activity, MPE and PPFs （partially purified fractions） of E. officinalis with two sets of mice, each mouse was inoculated with 1 × 104/mL oftrypanosomes and treated （48 h post inoculation） at concentrations （12.5, 25, 50, 100 and 200 mg/kg body weight） were administered at dose rate of 100 [tL per mouse via intraperitoneal route （in treating parassitemic mice） to different groups of mice, 6 mice per concentration. HPLC of partially purified fractions ofE. officinalis was carried out with mobile phase ofacetonitdle： water （40：60） in gradient mode. In vitro, MPE induced immobilization and killing of the parasites in concentration-time dependent manner. Significant reduction of trypanosomes counts from concentration of 250μg/mL and complete killing of trypanosomes at 5th hour of observation, which was statistically equivalent to 4th hour of Diminazine Aceturate （Berenil）, standard reference drug used. HPLC of the partially purified fractions revealed two major prominent peaks at retention time of 1-4 min. In vivo, both MPE and PPFs of test material did prolong lives
文摘It is well known that herbivore-induced plant defenses alter host plant quality and can affect the behavior and performance of later arriving herbivores.Effects of sequential attacks by herbivores that either suppress or induce plant defenses are less well studied.We sequentially infested leaves of tomato plants with a strain of the phytophagous spider mite Tetranychus urticae that induces plant defenses and the closely related Tetranychus evansi, which suppresses plant defenses.Plant quality was quantified through oviposifion of both spider mite species and by measuring proteinase inhibitor activity using plant material that had been sequentially attacked by both herbivore species.Spider-mite oviposifion data show that T.evansi could suppress an earlier induction of plant defenses by T.urticae,and T.urticae could induce defenses in plants previously attacked by T.evansi in 1 day.Longer attacks by the second species did not result in further changes in oviposifion.Proteinase inhibitor activity levels showed that T.evansi suppressed the high activity levels induced by T.urticae to constitutive levels in 1 day,and further suppressed activity to levels similar to those in plants attacked by T.evansi alone.Attacks by T.urticae induced proteinase inhibitor activity in plants previously attacked by T.evansi,eventually to similar levels as induced by T.urticae alone.Hence,plant quality and plant defenses were significantly affected by sequential attacks and the order of attack does not affect subsequent performance,but does affect proteinase inhibitor activity levels.Based on our results,we discuss the evolution of suppression of plant defenses.
