Experimental parasitology最新文献

{"title":"Immune modulation of goat monocytes by Fasciola gigantica Legumain-1 protein (Fg-LGMN-1)","authors":"Muhammad Ehsan ,&nbsp;Rui-Si Hu ,&nbsp;Meng Wang ,&nbsp;Jun-Ling Hou ,&nbsp;Muhammad Rashid ,&nbsp;Muhammad Irfan Malik","doi":"10.1016/j.exppara.2023.108671","DOIUrl":"10.1016/j.exppara.2023.108671","url":null,"abstract":"<div><p>Legumains belonging to C_13 peptidase family of proteins, and are ubiquitously disseminated among all vertebrate and invertebrate organisms, and have been implicated in innumerable biological and cellular functionality. Herein, we characterized and evaluated immunoregulatory characteristics of Legumain-1 from <span><em>Fasciola gigantica</em></span><span> (Fg-LGMN-1) during its interaction with host immune cells<span>. The isopropyl-ß-d-thiogalactopyranoside (IPTG) stimulated RFg-LGMN-1 protein was positively detected by rat serum containing anti-RFg-LGMN-1 polyclonal antibodies<span>. Furthermore, the uptake of RFg-LGMN-1 by goat monocytes was successfully confirmed using Immunofluorescence Assay (IFA). The immunohistochemical analysis revealed the native localization of LGMN-1 protein on the periphery and internal structures such as suckers, pharynx, and genital pore of the adult parasite, thereby validating its presence in excretory-secretory (ES) products of </span></span></span><em>F. gigantica</em><span><span><span>. The RFg-LGMN-1 co-incubated with concanavalin-A (Con-A) stimulated the increase of interleukin 2 (IL-2), IL-10, and IL-17 in monocytes derived from </span>peripheral blood mononuclear cells (PBMCs) in the concentration-dependent manner. However, the IL-4 cytokine in response to the RFg-LGMN-1 protein declined. These results illuminated the role of LGMN-1 during the parasite-host interface. Our findings elaborated additional evidence that Legumain protein play a role in the manipulating </span>host immune responses during parasite infections. However, further evaluation of RFg-LGMN-1 protein in context of its immunomodulatory roles should be conducted to enhance our understandings of the mechanisms employed by </span><em>F. gigantica</em> to evade host immune responses.</p></div>","PeriodicalId":12117,"journal":{"name":"Experimental parasitology","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2023-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138567369","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biological evaluation of 1,3-benzodioxole acids points to 3,4-(methylenedioxy) cinnamic acid as a potential larvicide against Aedes aegypti (Diptera: Culicidae)","authors":"Mariza Severina de Lima Silva ,&nbsp;Marcilene Souza da Silva ,&nbsp;Rômulo Carlos Dantas da Cruz ,&nbsp;Bruno de Oliveira Veras ,&nbsp;Ivone Antonia de Souza ,&nbsp;Rafael Matos Ximenes ,&nbsp;Thiago Mendonça de Aquino ,&nbsp;Alexandre José da Silva Góes","doi":"10.1016/j.exppara.2023.108657","DOIUrl":"10.1016/j.exppara.2023.108657","url":null,"abstract":"<div><p><span><em>Aedes aegypti</em></span><span> serves as the primary vector for viruses<span> like dengue, Chikungunya, Zika, and yellow fever, posing a significant public health challenge in Brazil. Given the absence of approved vaccines for these diseases, effective mosquito control becomes paramount in preventing outbreaks. However, currently available chemical insecticides face issues related to toxicity and the emergence of resistance, necessitating the exploration of new active compounds. Drawing inspiration from natural products, we identified the 1,3-benzodioxole group as a key pharmacophore associated with insecticidal activity. Therefore, this study aimed to synthesize and assess the larvicidal activity of 1,3-benzodioxole acids against </span></span><em>Ae. aegypti</em>, as well as their toxicity in mammals. Among the compounds evaluated, 3,4-(methylenedioxy) cinnamic acid (compound 4) demonstrated larvicidal activity. It exhibited LC₅₀ and LC₉₀ values of 28.9 ± 5.6 and 162.7 ± 26.2 μM, respectively, after 24 h of exposure. For reference, the positive control, temephos, displayed both LC₅₀ and LC₉₀<span> values below 10.94 μM. These findings underline the significance of the 3,4-methylenedioxy substituent on the aromatic ring and the presence of a double bond in the aliphatic chain for biological activity. Furthermore, compound 4 exhibited no cytotoxicity towards human peripheral blood mononuclear cells, even at concentrations up to 5200 μM. Lastly, in mice treated with 2000 mg kg</span>⁻¹, compound 4 showed mild behavioral effects and displayed no structural signs of toxicity in vital organs such as the kidney, liver, spleen, and lungs.</p></div>","PeriodicalId":12117,"journal":{"name":"Experimental parasitology","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2023-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138477050","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Single and combination treatment of Toxoplasma gondii infections with a bumped kinase inhibitor and artemisone in vitro and with artemiside in experimentally infected mice","authors":"Carling Schlange ,&nbsp;Joachim Müller ,&nbsp;Dennis Imhof ,&nbsp;Kai Pascal Alexander Hänggeli ,&nbsp;Ghalia Boubaker ,&nbsp;Luis-Miguel Ortega-Mora ,&nbsp;Ho Ning Wong ,&nbsp;Richard K. Haynes ,&nbsp;Wesley C. Van Voorhis ,&nbsp;Andrew Hemphill","doi":"10.1016/j.exppara.2023.108655","DOIUrl":"10.1016/j.exppara.2023.108655","url":null,"abstract":"<div><p>In previous studies, the artemisinin derivatives artemisone, its pro-drug artemiside and the bumped-kinase inhibitor BKI-1748 were effective against <em>T. gondii</em> via different modes of action. This suggests that they may act synergistically resulting in improved efficacies <em>in vitro</em> and <em>in vivo.</em> To test this hypothesis, the compounds were applied alone and in combination to <em>T. gondii</em> infected human fibroblast host cells in order to determine their inhibition constants and effects on cellular ultrastructure. In addition, the efficacy of either single- or combined treatments were assessed in an acute TgShSp1-oocyst infection model based on CD1 outbred mice. Whereas the IC₅₀ of the compounds in combination (42 nM) was close to the IC₅₀ of BKI-1748 alone (46 nM) and half of the IC₅₀ of artemisone alone (92 nM), the IC₉₀ of the combination was half of the values found with the single compounds (138 nM vs. ca. 270 nM). Another indication for synergistic effects <em>in vitro</em> were distinct alterations of the cellular ultrastructure of tachyzoites observed in combination, but not with the single compounds. These promising results could not be reproduced <em>in vivo</em>. There was no decrease in number of <em>T. gondii</em> positive brains by either treatment. However, the levels of infection in these brains, i. e. the number of tachyzoites, was significantly decreased upon BKI-1748 treatment alone, and the combination with artemiside did not produce any further decrease. The treatment with artemiside alone had no significant effects. A vertical transmission model could not be established since artemiside strongly interfered with pregnancy and caused abortion. These results show that is difficult to extrapolate from promising <em>in vitro</em> results to the situation <em>in vivo</em>.</p></div>","PeriodicalId":12117,"journal":{"name":"Experimental parasitology","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2023-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0014489423001960/pdfft?md5=4cfa3e2ce4988b18b32bcbe8db1382a5&pid=1-s2.0-S0014489423001960-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138046630","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development and evaluation of the in vitro schistosomicidal activity of solid dispersions based on 2-(-5-bromo-1-H-indole-3-yl-methylene)-N-(naphthalene-1-ylhydrazine-carbothiamide","authors":"Thâmara Carollyne de Luna Rocha ,&nbsp;Maria Joanellys dos Santos Lima ,&nbsp;Jéfferson Luan Nunes do Nascimento ,&nbsp;Jamerson Ferreira de Oliveira ,&nbsp;Emerson de Oliveira Silva ,&nbsp;Victor Hugo Barbosa dos Santos ,&nbsp;André de Lima Aires ,&nbsp;Victor de Albuquerque Wanderley Sales ,&nbsp;Talita Atanazio Rosa ,&nbsp;Pedro José Rolim Neto ,&nbsp;Mônica Camelo Pessôa de Azevedo Albuquerque ,&nbsp;Maria do Carmo Alves de Lima ,&nbsp;Rosali Maria Ferreira da Silva","doi":"10.1016/j.exppara.2023.108626","DOIUrl":"10.1016/j.exppara.2023.108626","url":null,"abstract":"<div><p><span><span><span>Among all the neglected diseases, schistosomiasis is considered the second most important parasitic infection after malaria. Praziquantel is the most widely used drug for this disease, but its exclusive use may result in the development of drug-resistant schistosomiasis. To increase the control of the disease, new drugs have been developed as alternative treatments, among them 2-(-5-bromo-1-h-indole-3-yl-methylene)-N-(naphthalene-1-ylhydrazine-carbothiamide (LQIT/LT-50), which showed promising schistosomicidal activity in </span>nonclinical studies. However, LQIT/LT-50 presents low solubility in water, resulting in reduced bioavailability. To overcome this solubility problem, the present study aimed to develop LQIT/LT-50 solid dispersions for the treatment of schistosomiasis. Solid dispersions were prepared through the solvent method using Soluplus©, polyethylene glycol (PEG) or polyvinylpyrrolidone (PVP K-30) as hydrophilic carriers. The formulations with the best results in the compatibility tests, aqueous solubility and preliminary stability studies have undergone solubility tests and physicochemical characterizations by Fourier-transform infrared spectroscopy (FTIR), x-ray diffractometry (XRD), exploratory differential calorimetry (DSC), thermogravimetry (TG) and </span>Raman spectroscopy. Finally, the schistosomicidal activity was evaluated </span><em>in vitro</em>. The phycochemical analyzes showed that when using PVP K-30, there was an interaction between the PVP K-30 and LQIT/LT-50, proving the successful development of the solid dispersion. Furthermore, an increase in the solubility of the new system was observed (LQIT/LT-50:PVP K-30) in addition to the improvement in the <em>in vitro</em> shistosomidal activity at 1:4 (w/w) molar ratio (i.e., 20% drug loading) when compared to LQIT/LT-50 alone. The development of the LQIT/LT-50:PVP K-30 1:4 solid dispersion is encouraging for the future development of new pharmaceutical solid formulations, aiming the schistosomicidal treatment.</p></div>","PeriodicalId":12117,"journal":{"name":"Experimental parasitology","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2023-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135764762","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microencapsulation of Bacillus thuringiensis strains for the control of Aedes aegypti","authors":"Juliete L. Viana ,&nbsp;Joelma S. da Silva ,&nbsp;Gabriela C. de Mattos ,&nbsp;Martina C.C. Pinto ,&nbsp;Luciana da S. Dutra ,&nbsp;Larissa L. de A. Carvalho ,&nbsp;José Carlos C. da S. Pinto ,&nbsp;Valéria Cristina S. Pinheiro ,&nbsp;Rosemary A. Roque","doi":"10.1016/j.exppara.2023.108654","DOIUrl":"10.1016/j.exppara.2023.108654","url":null,"abstract":"<div><p><span>In this study, we investigated the microencapsulation<span> of two strains of the entomopathogenic bacteria </span></span><span><em>Bacillus thuringiensis</em></span> (<em>B. thuringiensis</em>) (BtMA-750 and BtMA-1114), which are biopesticides of high toxicity for the mosquito vector <span><em>Aedes aegypti</em></span>. The encapsulation of different concentrations of microorganisms in starch microparticles was evaluated, and the inverse suspension polymerization technique was explored. It was possible to observe that the higher amounts of the biopesticide caused a slight decrease in the diameter of the particles; however, even when encapsulated, the biopesticide still presents an average diameter that is able to be consumed by the larvae of <em>Aedes aegypti</em>. Furthermore, it was noticed that the presence of both of the <em>B. thuringiensis</em><span> strains did not affect the thermal stability<span> of the particles. The microencapsulated bacterial strains<span> presented a high number of viable spores and preserved the expression of proteins with molecular masses corresponding to the insecticidal toxins Cry and Cyt, indicating that the encapsulation process was conducted satisfactorily. Finally, the encapsulated strains were tested against </span></span></span><em>Ae. aegypti</em> larvae and maintained 100% larval mortality even after 35 days. Therefore, microencapsulation of <em>B. thuringiensis</em><span> not only guarantees the bacterial activity, but also prolongs the action of the biopesticide. Collectively, such findings highlight the great potential of the new biopesticides, which may help to reduce the population indices of the mosquito vector </span><em>Ae. aegypti</em> via a sustainable and environment-friendly route.</p></div>","PeriodicalId":12117,"journal":{"name":"Experimental parasitology","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2023-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"92153360","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The common bed bug Cimex lectularius synthesizes hemozoin as an essential defense against the toxic effects of heme","authors":"Vladimir Fazito do Vale ,&nbsp;Brenda Hevillin Rocha Simtob ,&nbsp;Luccas Gabriel Ferreira Malta ,&nbsp;Ezequias Pessoa de Siqueira","doi":"10.1016/j.exppara.2023.108653","DOIUrl":"10.1016/j.exppara.2023.108653","url":null,"abstract":"<div><p><span>The common bed bug </span><em>Cimex lectularius</em><span><span> (Linnaeus 1758) is an ectoparasite that feeds preferably on human blood, being considered an important public health issue. Blood-feeding is a challenging process for </span>hematophagous organisms, and one of the inherent risks with this kind of diet is the liberation of high doses of free heme after the digestion of hemoglobin. In order to deal with this potent cytotoxic agent, such organisms have acquired different defense mechanisms. Here, we use UV–visible spectrophotometry and infrared spectroscopy to show that </span><em>C</em>. <em>lectularius</em><span><span> crystalizes free heme to form the much less dangerous compound, hemozoin. According to our results, the peak of formation of hemozoin in the intestinal contents occurred 4–5 days after the blood meal, primarily in the posterior midgut. The quantification of the rate of conversion of heme to hemozoin revealed that at the end of digestion all the heme was in the form of hemozoin. Inhibition of the synthesis of hemozoin using the anti-malarial drug quinine led to an increase in both catalase activity in the intestinal epithelium and the mortality of the </span>bed bugs<span>, indicating that the insects were unable to cope with the oxidative stress generated by the overload of free heme. The data presented here show for the first time how </span></span><em>C. lectularius</em> deals with free heme, and how the process of formation of hemozoin is essential for the survival of these insects. Since resistance to insecticides is a common feature among field populations of bed bugs, there is an urgent need to develop alternative control methods. Thus, targeting the synthesis of hemozoin emerges as a possible novel strategy to fight bed bugs.</p></div>","PeriodicalId":12117,"journal":{"name":"Experimental parasitology","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2023-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89717544","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ribonucleotide reductase as a therapeutic target for drug repurposing as anthelmintics","authors":"Marcelo Pasa Panesso ,&nbsp;Martin Cancela ,&nbsp;Renato Kulakowski Corá ,&nbsp;Jéssica Andrade Paes ,&nbsp;Gabriela Prado Paludo ,&nbsp;Henrique Bunselmeyer Ferreira","doi":"10.1016/j.exppara.2023.108641","DOIUrl":"10.1016/j.exppara.2023.108641","url":null,"abstract":"<div><p><span><span>Visceral cestodiases, like echinococcoses<span> and cysticercoses<span>, are zoonoses of worldwide distribution and are responsible for public health problems in many countries, especially in underdeveloped regions. Current treatments have low efficiency and there are few drugs currently in use for chemotherapy, making the development of new </span></span></span>anthelmintics<span> an urgent matter. The nucleotide salvage pathways are the only ones available for nucleotide synthesis<span> in cestodes and other parasitic helminths, and, here, we used </span></span></span><em>in silico</em> approaches to assess the potential of the enzymes in these pathways as targets for drug repurposing as anthelminthics. First, a genomic survey allowed to identify a repertoire of 28 enzymes of the purine and pyrimidine salvage pathways from the cestode <span><em>Echinococcus granulosus</em></span><span> sensu stricto. Regarding purines, the parasite relies on salvaging free bases rather than salvaging nucleosides. Pyrimidines, on the other hand, can be salvaged from both bases and nucleosides. Druggability of the parasite enzymes was assessed, as well as the availability of commercial inhibitors for them. Druggable enzymes were then ranked according to their potential for drug repurposing and the 17 most promising enzymes were selected for evolutionary analyses. The constructed phylogenetic trees<span> allowed to assess the degree of conservation among ortholog enzymes from parasitic helminths and their mammalian hosts. Positive selection is absent in all assessed flatworm enzymes. A potential target enzyme for drug repurposing, ribonucleotide reductase (RNR), was selected for further assessment. RNR 3D-modelling showed structural similarities between the </span></span><em>E. granulosus</em> and the human orthologs suggesting that inhibitors of the human RNR should be effective against the <em>E. granulosus</em> enzyme. In line with that, <em>E. granulosus</em> protoscolices treated <em>in vitro</em><span> with the inhibitor hydroxyurea had their viability and DNA synthesis reduced. These results are consistent with nucleotide synthesis inhibition and confirm the potential of a nucleotide salvage inhibitors for repurposing as an anthelmintic.</span></p></div>","PeriodicalId":12117,"journal":{"name":"Experimental parasitology","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2023-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72208972","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of Brown and red seaweeds-extracts as a novel larvicidal agent against the deadly human diseases-vectors, Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus","authors":"Annamalai Aravinth ,&nbsp;Sundaramoorthy Dhanasundaram ,&nbsp;Pachiappan Perumal ,&nbsp;Chinnaperumal Kamaraj ,&nbsp;Safir Ullah Khan ,&nbsp;Amir Ali ,&nbsp;Chinnasamy Ragavendran ,&nbsp;Vadivel Amutha ,&nbsp;Rajendran Rajaram ,&nbsp;Perumal Santhanam ,&nbsp;Juan Pedro Luna-Arias ,&nbsp;Zia-ur-Rehman Mashwani","doi":"10.1016/j.exppara.2023.108651","DOIUrl":"10.1016/j.exppara.2023.108651","url":null,"abstract":"<div><p>Infectious diseases such as malaria, dengue, and yellow fever are predominantly transmitted by insect vectors like <span><em>Anopheles stephensi</em><span><em>, </em><em>Aedes aegypti</em></span></span>, and <span><em>Culex quinquefasciatus</em></span> in tropical regions like India and Africa. In this study, we assessed the larvicidal activity of commonly found seaweeds, including <span><em>Padina gymnospora, P. pavonica, </em><em>Gracilaria</em><em> crassa, Amphiroa fragilissima</em></span>, and <em>Spatoglossum marginatum</em>, against these mosquito vectors. Our findings indicate that extracts from <em>P. gymnospora</em> Ethyl Acetate (PgEA), <em>P. pavonica Hexane</em> (PpH), and <em>A. fragilissima</em> Ethyl Acetate (AfEA) displayed the highest larval mortality rates for <em>A. stephensi</em>, with LC50 values of 10.51, 12.43, and 6.43 μg/mL, respectively. Additionally, the PgEA extract from <em>P. gymnospora</em> exhibited the highest mortality rate for <em>A. aegypti</em>, with an LC50 of 27.0 μg/mL, while the PgH extract from the same seaweed showed the highest mortality rate for <em>C. quinquefasciatus</em><span>, with an LC50 of 9.26 μg/mL. Phytochemical analysis of the seaweed extracts revealed the presence of 71 compounds in the solvent extracts. Fourier-transform infrared spectra of the selected seaweeds indicated the presence of functional groups such as alkanes, alcohols, and phenols. Gas chromatography–mass spectrometry analysis of the seaweeds identified major compounds, including hexadecanoic acid in PgEA, tetradecene (e)- in PpEA, octadecanoic acid in GcEA, and 7-hexadecene, (z)-, and trans-7-pentadecene in SmEA.</span></p></div>","PeriodicalId":12117,"journal":{"name":"Experimental parasitology","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2023-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72014038","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of synergism in essential oils against the cattle tick Rhipicephalus microplus in Burkina Faso","authors":"Anass Coulibaly ,&nbsp;Abel S. Biguezoton ,&nbsp;Delphine M. Hema ,&nbsp;Firmin F. Dah ,&nbsp;Ignace Sawadogo ,&nbsp;Rémy K. Bationo ,&nbsp;Moussa Compaoré ,&nbsp;Martin Kiendrebeogo ,&nbsp;Roger C.H. Nébié","doi":"10.1016/j.exppara.2023.108643","DOIUrl":"10.1016/j.exppara.2023.108643","url":null,"abstract":"<div><p>The cattle tick <em>Rhipicephalus microplus</em> affects animal production economically by reducing weight gain and milk production and causing diseases, such as babesiosis and anaplasmosis. Using synthetic acaricides to reduce their incidence has caused the emergence of resistant tick populations. The present study aimed to assess the <em>in vitro</em> acaricidal activity of combinations of essential oils (EOs) from <em>Ocimum americanum</em>, <em>Ocimum gratissimum</em>, and <em>Lippia multiflora</em> against <em>R. microplus</em> larvae. In fact, numerous biological properties have been reported on EOs from these three plants, including acaricidal properties. Hence, a larval immersion test was performed using a population of <em>R. microplus</em> resistant to synthetic acaricides used in Burkina Faso. Results revealed that EO from <em>O. gratissimum</em> was the most effective on <em>R. microplus</em> larvae with LC₅₀ and LC₉₀ values at 10.36 and 15.51 mg/mL, respectively. For EO combinations, the most significant synergistic effect was obtained by combination 6 (1/3 <em>O. americanum</em> + 2/3 <em>O. gratissimum</em> +1/6 <em>L. multiflora</em>), with a combination index value of 0.44. All combinations presented dose reduction index &gt;1, indicating a favorable dose reduction. According to the literature, this is the first study to determine the combination effect of EOs from the abovementioned plants in controlling <em>R. microplus</em> activity <em>in vitro.</em> Thus, the combination of these EOs is an alternative to control the resistant populations of invasive cattle ticks.</p></div>","PeriodicalId":12117,"journal":{"name":"Experimental parasitology","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2023-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72208971","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"TLR2, TLR3, TLR4, TLR9 and TLR11 expression on effector CD4+ T-cell subsets in Leishmania donovani infection","authors":"Ashok Patidar ,&nbsp;Divanshu Shukla ,&nbsp;Neelam Bodhale,&nbsp;Bhaskar Saha","doi":"10.1016/j.exppara.2023.108645","DOIUrl":"10.1016/j.exppara.2023.108645","url":null,"abstract":"<div><p>T-cells play a central role in cell-mediated immunity. While activation of T-cells is major histocompatibility-restricted, the Toll-like receptors (TLRs)- a family of proteins that recognize conserved molecular patterns present on the pathogens-are not well-studied for their expression and function in T-cells. As any association of TLR expression profiles with an effector T-cell subset is unknown, we analyze BALB/c mice-derived CD4⁺ and CD8⁺ T-cells’ TLR expression profiles. We report: CD4⁺t-bet⁺<span> T-cells are frequent in TLR2</span>^Low<span>TLR3</span>^High<span>TLR4</span>^Low subpopulation, CD4⁺<span>GATA3</span>⁺ T-cells are frequent within the cells with intermediate expression of TLR2, TLR3, TLR4 and TLR11, CD4⁺FoxP3⁺ T-cells in TLR2^HighTLR3^High cells whereas CD4⁺RORγt ⁺ T-cells are frequent in TLR2^LowTLR3^LowTLR4^LowTLR11^Low cells. CD4⁺ effector T-cell subsets may therefore show association with TLRs- TLR3, in particular-expression. In <span><em>Leishmania donovani</em></span> infection in BALB/c mice, TLR3 expression on both CD4⁺ and CD8⁺ T-cells is reduced. Poly-I:C, a TLR3 ligand, do not have any distinctive effects on the CD4⁺ effector T-cell subsets. These data suggest that TLRs on T-cells may not function as a primary receptor that controls T-cell function but their distinctive expression profiles on different T-cell subsets suggest plausible immunomodulatory role.</p></div>","PeriodicalId":12117,"journal":{"name":"Experimental parasitology","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2023-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72208973","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}