Parasites & Vectors最新文献

{"title":"Seasonal variation of anti-Leishmania infantum antibodies and laboratory abnormalities in dogs with leishmaniosis.","authors":"Maria Alfonsa Cavalera, Annamaria Uva, Mariaelisa Carbonara, Jairo Alfonso Mendoza-Roldan, Xavier Roura, José Joaquín Cerón, Domenico Otranto, Andrea Zatelli","doi":"10.1186/s13071-025-06940-7","DOIUrl":"10.1186/s13071-025-06940-7","url":null,"abstract":"<p><strong>Background: </strong>In dogs affected by leishmaniosis, laboratory abnormalities and anti-Leishmania antibody titers are crucial for initial and relapse diagnosis, as well as for informing therapeutic decisions. This study aimed to evaluate laboratory findings in L. infantum seropositive dogs during and after the transmission season on the basis of the evidence that anti-L. infantum antibody titers vary between sand fly and nonsand fly transmission periods in dogs from areas where leishmaniosis is endemic.</p><p><strong>Methods: </strong>In September 2021 (transmission season; T1) and January 2022 (nontransmission season; T2), L. infantum seropositive dogs were physically examined, and blood sampling was performed for laboratory tests. At both time points, dogs underwent routine hematology, a complete biochemical panel including acute phase proteins (i.e., C-reactive protein [CRP] and ferritin), erythrocyte sedimentation rate [ESR] measurement, serum capillary electrophoresis, and serology for L. infantum. Potential coinfections with other arthropod-borne (Anaplasma phagocythophilum, Ehrlichia canis, Dirofilaria spp.) and snail-borne (Angiostrongylus vasorum) pathogens were also excluded.</p><p><strong>Results: </strong>Total protein and CRP levels were slightly reduced in T2 compared with T1, although the difference was not statistically significant. Antibody titers also decreased in 10 out of 18 dogs (55.5%), with two (20%) becoming seronegative, while they remained constant in eight out of 18 dogs (44.4%). Furthermore, a statistically significant reduction was observed in globulin percentage, ferritin, and ESR, whereas albumin percentage and total iron levels significantly increased.</p><p><strong>Conclusions: </strong>Anti-L. infantum antibody titers and laboratory abnormalities in seropositive dogs living in endemic areas for leishmaniosis may vary. This variation may be related to vector seasonality and, consequently, dogs' exposure to sand fly saliva and potential reinfections. These results reinforce the importance of considering the sampling season in the clinical evaluation and management of dogs affected by leishmaniosis to avoid misdiagnosis and unnecessary antileishmanial treatments.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"18 1","pages":"319"},"PeriodicalIF":3.5,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12315306/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144765142","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Insecticide resistance status and high frequency of kdr mutations in Aedes aegypti in Tegucigalpa, Honduras.","authors":"Cindy Reyes-Perdomo, Denis Escobar, Luis Galo, Oscar Urrutia, Rita Lucrecia Vizcaino, Audrey Lenhart, Gustavo Fontecha","doi":"10.1186/s13071-025-06953-2","DOIUrl":"10.1186/s13071-025-06953-2","url":null,"abstract":"<p><strong>Background: </strong>Aedes aegypti is the main vector of arboviruses in the Americas. Insecticide use remains the primary method for outbreak control, but prolonged application exerts selective pressure that promotes resistance. This study aimed to assess insecticide resistance and characterize key knockdown resistance (kdr) mutations in Ae. aegypti populations from the Central District of Honduras.</p><p><strong>Methods: </strong>Larvae were collected from four localities between May and June 2023. Susceptibility to four insecticides was evaluated via bioassays. Frequencies of the F1534C and V1016I kdr alleles and their haplotypes were determined, and sequencing of the vgsc gene was performed for further genotyping.</p><p><strong>Results: </strong>A total of 1592 Ae. aegypti females were phenotyped. All populations were resistant to permethrin and malathion, and two were resistant to deltamethrin; all were susceptible to bendiocarb. The 1534C mutant allele was fixed (1.0), and 1016I had an overall frequency of 0.89, with local variation from 0.48 to 1.0.</p><p><strong>Conclusions: </strong>Widespread resistance to commonly used insecticides was detected in Ae. aegypti from the Central District. High frequencies of kdr mutations underscore the need for continuous resistance monitoring to guide effective vector control strategies in Honduras.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"18 1","pages":"321"},"PeriodicalIF":3.5,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12317443/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144765140","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact on the Leishmania mexicana transcriptome due to knockout of genes encoding orthologs of methyltransferases involved in m1A and m5C mRNA modifications.","authors":"Angela Moreira Bezerra, Ariely Barbosa Leite, Christian Robson de Souza Reis, João Luiz de Lemos Padilha Pitta, Suellen Rodrigues Maran, Nilmar Silvio Moretti, Danielle Maria Nascimento Moura, Antonio Mauro Rezende","doi":"10.1186/s13071-025-06969-8","DOIUrl":"10.1186/s13071-025-06969-8","url":null,"abstract":"<p><strong>Background: </strong>Chemical modifications of mRNAs constitute an alternative mechanism for gene expression regulation, which involves proteins responsible for adding, recognizing and removing these modifications. While orthologs of enzymes involved in adding m1A (TRMT6/TRMT61A) and m5C (NSUN2) modifications are present in trypanosomatid species, a clear understanding of their biological role in these parasites is necessary.</p><p><strong>Methods: </strong>To shed light on this, we genetically manipulated the TRMT61A and NSUN2 protein-encoding genes in the Leishmania mexicana species using the CRISPR-Cas9 editing technique and analyzed the impact on cell growth and differentiation as well as the global gene expression profile.</p><p><strong>Results: </strong>Deletion of the genes investigated here caused changes in the normal pattern of L. mexicana differentiation, and functional analyses of differentially expressed genes in the mutants unveiled significant biological effects. For the TRMT61A gene, transcripts related to nucleotide metabolism, translation, protein folding and refolding were affected. For the NSUN2 genes, enrichment analysis indicated impacts on biological processes mostly related to nucleotide metabolism and DNA binding.</p><p><strong>Conclusions: </strong>Our findings provide insights into the role of these methyltransferases orthologs in the regulation of trypanosomatid transcriptome, contributing to our understanding of gene expression control in this parasite.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"18 1","pages":"315"},"PeriodicalIF":3.5,"publicationDate":"2025-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12315365/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144760760","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Senegalese and Brazilian strains of Schistosoma mansoni exhibit high compatibility with Biomphalaria pfeifferi and Biomphalaria glabrata.","authors":"Mbéré Sarr, Malick Diop, Abdoulaye Jacque Bakhoum, Souleymane Doucoure, Doudou Sow, Cheikh Tidiane Bâ, Cheikh Sokhna, Jérôme Boissier, Bruno Senghor","doi":"10.1186/s13071-025-06918-5","DOIUrl":"10.1186/s13071-025-06918-5","url":null,"abstract":"<p><strong>Background: </strong>Intestinal schistosomiasis, caused by Schistosoma mansoni, is endemic in both Africa and South America. In Senegal and Brazil, S. mansoni is transmitted by Biomphalaria pfeifferi and Biomphalaria glabrata, respectively. With increasing human migration from Senegal to the Americas, there is a potential risk of transferring parasite strains across continents. Understanding the compatibility between Schistosoma species and strains, and snail hosts is therefore essential. This study investigated the compatibility of two S. mansoni strains from Senegal (SmSEN) and Brazil (SmBRA) with both B. pfeifferi (BpSEN) and B. glabrata (BgBRA) originating from Senegal and Brazil, respectively.</p><p><strong>Methods: </strong>Four infection combinations were performed: (1) SmSEN + BpSEN (2) SmSEN + BgBRA (3) SmBRA + BgBRA, and (4) SmBRA + BpSEN. A minimum of 72 snails were individually exposed to five miracidia per combination.</p><p><strong>Results: </strong>The data show high compatibility between Brazilian and Senegalese S. mansoni with B. pfeifferi (92.4% and 77.3%, respectively). In contrast, both strains showed a low compatibility with B. glabrata, with rates of 67.3 and 48% for the Brazilian and Senegalese S. mansoni, respectively.</p><p><strong>Conclusions: </strong>The high compatibility between S. mansoni and Biomphalaria species from Senegal and Brazil highlights the adaptability of S. mansoni to infect different Biomphalaria species across geographically distinct regions. These findings emphasize the importance of monitoring areas at risk of schistosomiasis emergence, particularly in the context of human migration and the invasive spread of Biomphalaria species into novel environments.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"18 1","pages":"314"},"PeriodicalIF":3.5,"publicationDate":"2025-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12315208/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144760763","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The β-triketone, nitisinone, kills insecticide-resistant mosquitoes through cuticular uptake.","authors":"Zachary Thomas Stavrou-Dowd, George Parsons, Clair Rose, Faye Brown, Rosemary Susan Lees, Álvaro Acosta-Serrano, Lee Rafuse Haines","doi":"10.1186/s13071-025-06939-0","DOIUrl":"10.1186/s13071-025-06939-0","url":null,"abstract":"<p><strong>Background: </strong>Insecticide resistance in disease-transmitting arthropods of agricultural, veterinary, and public health significance poses a significant threat to vector control programs worldwide. Previous studies demonstrated that blood-feeding arthropod vectors experience high mortality when ingesting blood containing inhibitors of 4-hydroxyphenylpyruvate dioxygenase (HPPD), the second enzyme in tyrosine metabolism. This study investigated the mosquitocidal efficacy of HPPD inhibitors from the β-triketone class of herbicides against both susceptible and pyrethroid-resistant strains of three major disease vector species, including mosquitoes that transmit historical diseases such as malaria, reemerging infections such as dengue and Zika, and emerging viral threats such as Oropouche and Usutu viruses.</p><p><strong>Methods: </strong>Four HPPD inhibitors (nitisinone, mesotrione, sulcotrione, and tembotrione) were screened using glass plate tarsal bioassays at 125 mg/m² against bloodfed Anopheles gambiae s.s. Kisumu. Nitisinone was selected for evaluation against susceptible and pyrethroid-resistant strains of An. gambiae s.s. Kisumu, An. gambiae s.l. Tiassalé 13, An. coluzzii VK7 2014, Culex quinquefasciatus Muhezha, and Aedes aegypti New Orleans. Mosquitocidal activity was assessed using glass plate tarsal contact bioassays, topical application assays (0.0001% to 1% w/v), and modified Centers for Disease Control and Prevention (CDC) bottle bioassays (0-30 μg per bottle). Female mosquitoes aged 3-5 days were bloodfed within 1 h before exposure. Mortality was recorded at 30 min and 24, 48, and 72 h post-exposure under controlled conditions. A total of 3 biological replicates of 30 mosquitoes per treatment were used.</p><p><strong>Results: </strong>Only nitisinone, and not mesotrione, sulcotrione, or tembotrione, exhibited significant mosquitocidal activity when bloodfed mosquitoes were exposed to treated surfaces. No significant differences in susceptibility to nitisinone were observed between insecticide-susceptible An. gambiae and strains harboring multiple insecticide-resistance mechanisms. The compound demonstrated consistent efficacy across all three mosquito species tested, indicating broad-spectrum activity against major disease vectors.</p><p><strong>Conclusions: </strong>This study demonstrates that nitisinone exhibits a novel mode of action distinct from current Insecticide Resistance Action Committee (IRAC) classifications by specifically targeting blood digestion processes. Its efficacy against resistant strains and potential for integration into existing vector control interventions, such as treated bednets and indoor residual spraying, highlight nitisinone as a promising candidate for expanding strategies against malaria, dengue, Zika, and other emerging viral diseases.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"18 1","pages":"316"},"PeriodicalIF":3.5,"publicationDate":"2025-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12315382/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144760764","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Catechin gallate triggers metabolomic and lipidomic alteration in Toxoplasma gondii.","authors":"Jazmyn R Greggs, Homa Nath Sharma, Daniel A Abugri","doi":"10.1186/s13071-025-06869-x","DOIUrl":"10.1186/s13071-025-06869-x","url":null,"abstract":"&lt;p&gt;&lt;strong&gt;Background: &lt;/strong&gt;Toxoplasma gondii is a zoonotic parasite, the causative agent of toxoplasmosis, which has global importance owing to its significant socioeconomic, public health, and veterinary burdens. Toxoplasmosis is currently treated with a combination of pyrimethamine and sulfadiazine. These drugs have treatment failures and toxicity and are ineffective against the bradyzoite stage. Hence, there is a need for new inhibitors against T. gondii. Catechin gallate (CG) is a known antioxidant with demonstrated antiparasitic properties. However, little is known about its anti-Toxoplasma gondii activity and mechanism of action.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Methods: &lt;/strong&gt;Here, we assess the effect of CG on human telomerase reverse transcriptase immortalized foreskin fibroblast (hTERT) cells, cytotoxicity, and inhibitory activity of the RH-RFP (type I) strain of T. gondii tachyzoite. Inhibitory and cytotoxicity activities were measured by a fluorescent plate reader, and the data were analyzed using Graph Pad Prism software. In addition, to predict the possible mechanism of CG action, hTERT cells were cultured in a T25 flask and infected with RH-RFP parasites, followed by CG administration and incubation for 48 h. Parasites were quenched under ice, and the parasites were purified from host cells and extracted with chloroform-methanol. The extracts containing the lipids and metabolites were analyzed using liquid chromatography-mass spectrometry (LC-MS).&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Results: &lt;/strong&gt;To address this research question, we tested the in vitro inhibitory activity of CG against parasite growth at 48 h and 72 h. The half-maximal inhibitory concentration (IC&lt;sub&gt;50&lt;/sub&gt;) values against tachyzoite growth were calculated to be 10.07 (8.31-12.20) µM and 7.057 (5.98-8.32) µM for 48 h and 72 h, respectively. We identified 5-formyl-tetrahydromethanopterin; 5-(6-hydroxy-6-methyloctyl)-2,5-dihydrofuran-2-one; trans-3-indoleacrylic acid; 5,5-dimethyl-2-{[(2-phenylacetyl)amino]methyl}-1,3-thiazolane-4-carboxylic acid; 5'-S-Ethyl-5'-thioadenosine; L-Norleucine; and norepinephrine sulfate as the most produced during the CG treatment. For the lipidomics analysis, we identified the production of several sphingolipid species, including ceramides, dihydroceramide, and sphingosine, which are associated with apoptosis and autophagy. The limited number of sphingomyelin and sphingosine-1-phosphate identified, which are known to promote proliferation, suggests that CG may be affecting T. gondii parasites' proliferation. In addition, oxidized fatty acids (3-hydroxypropyl stearate and (R)-3-hydroxy myristic acid) were observed in both treatments with low production, which confers oxidative stress induction on parasites.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Conclusions: &lt;/strong&gt;The study showed that CG had inhibitory activity against T. gondii growth and caused metabolite and lipid alterations in T. gondii. This requires future studies on the enzymes associated with the biosynthesis of these metab","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"18 1","pages":"317"},"PeriodicalIF":3.5,"publicationDate":"2025-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12315274/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144760759","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigating the role of stable flies (Stomoxys calcitrans) and biting midges of the genus Culicoides as potential mechanical vectors of African swine fever virus in Lithuania, Poland and Romania.","authors":"Sofie Dhollander, Oana-Maria Balmoș, Eleonora Cattaneo, José Abrahantes Cortiñas, Anette Ella Boklund, Anna Szczotka-Bochniarz, Andrei Daniel Mihalca, Lina Mur, Maciej Frant, Anna Gal-Cisoń, Malgorzata Kwasnik, Wojciech Rozek, Alvydas Malakauskas, Marius Masiulis, Jurga Turcinaviciene, Theodora Chesnoiu, Krzysztof Jazdzewski, Jerzy Rola, Florica Barbuceanu, Miguel Ángel Miranda, Jan Arend Stegeman","doi":"10.1186/s13071-025-06816-w","DOIUrl":"10.1186/s13071-025-06816-w","url":null,"abstract":"<p><strong>Background: </strong>Since its emergence in Georgia in 2007, the seasonal pattern of African swine fever virus (ASFV) genotype II outbreaks in European pig populations has been evident. It is hypothesized that summer-related farming practices, along with the increased activity and abundance of arthropod vectors during warmer months, contribute to the increased incidence of these outbreaks during this period. This study investigated the potential role of stable flies (Stomoxys calcitrans) and biting midges of the genus Culicoides as mechanical vectors of ASFV. In addition, the potential distribution and abundance of different species of Culicoides biting midges on pig farms was investigated.</p><p><strong>Methods: </strong>From August 2021 to August 2023, vector surveillance was conducted as part of a case-control study on 42 outbreak farms and 70 control farms across Romania, Lithuania, and Poland. Collected insect specimens were pooled and tested for ASFV DNA using real-time polymerase chain reaction (PCR).</p><p><strong>Results: </strong>A total of 8604 biting midges of the genus Culicoides specimens and 742 S. calcitrans flies were collected, with ASF DNA detected in 27 out of 1219 insect pools. Positive pools were predominantly observed in Culicoides punctatus, C. newsteadi, and the Obsoletus complex, with most detections occurring in August. However, ASFV isolation was unsuccessful. Statistical analyses revealed no significant association between farm status (outbreak versus control) and ASFV DNA detection in pools of biting midges of the genus Culicoides, likely due to limited sample size. Additionally, two ASFV-positive S. calcitrans pools were identified, supporting their potential role as mechanical vehicles for ASFV. The findings highlight the affinity of C. punctatus, C. newsteadi, and the Obsoletus complex and S. calcitrans for pig farms - an aspect that was previously undocumented. This association may increase the likelihood of ASFV acquisition and dissemination by these species. Environmental factors, such as pig farm density and proximity to other hosts, likely influence this risk.</p><p><strong>Conclusions: </strong>These results emphasize the importance of vector control strategies, including insect netting, to mitigate ASFV transmission risks. Further research is needed to understand the dynamics of ASFV infection in arthropods. Notably, this study also reports the first identification of Culicoides riethi and Culicoides salinarius in Lithuania.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"18 1","pages":"312"},"PeriodicalIF":3.5,"publicationDate":"2025-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12312455/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144760761","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pulmonary hypertension and NT-proBNP dynamics during the course of adulticide treatment in dogs naturally infected by Dirofilaria immitis.","authors":"Noelia Costa-Rodríguez, Daniel Julio Vera-Rodríguez, Soraya Falcón-Cordón, Beatriz Regina Morales, José Alberto Montoya-Alonso, Rodrigo Morchón, Elena Carretón","doi":"10.1186/s13071-025-06945-2","DOIUrl":"10.1186/s13071-025-06945-2","url":null,"abstract":"<p><strong>Background: </strong>Pulmonary hypertension (PH) is a frequent complication in dogs with heartworm disease caused by Dirofilaria immitis. Although echocardiography remains the main diagnostic tool, its operator- and preload-dependence may limit accuracy. N-terminal pro-B-type natriuretic peptide (NT-proBNP) is a cardiac biomarker that increases in response to ventricular wall stress and may be useful for monitoring right-sided heart disease. This study aimed to evaluate NT-proBNP concentrations in dogs with precapillary PH due to heartworm disease during adulticide treatment.</p><p><strong>Methods: </strong>In total, 90 dogs diagnosed with heartworm disease were prospectively enrolled and classified according to the presence of PH based on echocardiographic criteria. NT-proBNP concentrations were measured on days 0, 30, 60, and 90 of adulticide treatment. Additional data collected included the presence/absence of microfilariae, clinical signs, parasite burden, and renal values. Dogs received adulticidal therapy following current international guidelines. Statistical analyses assessed correlations between NT-proBNP levels, epidemiological, clinical and echocardiographic classification, and treatment progression.</p><p><strong>Results: </strong>Dogs with PH had significantly higher NT-proBNP concentrations at baseline compared with those without PH (2038 ± 1671 versus 583 ± 185 pmol/L, P < 0.001). NT-proBNP levels were also positively correlated with parasite burden (r = 0.530, P < 0.05), presence of clinical signs (r = 0.456, P < 0.05), and age (r = 0.29, P < 0.05). During treatment, a progressive decrease in NT-proBNP concentrations was observed in dogs with PH, while levels remained stable in dogs without PH. Receiver operating characteristic (ROC) analysis identified a cut-off of 1524.8 pmol/L for detecting moderate-to-severe PH (sensitivity: 99%, specificity: 87%).</p><p><strong>Conclusions: </strong>NT-proBNP is a valuable noninvasive biomarker for detecting and monitoring PH in dogs with heartworm disease. Its concentrations seem to reflect parasite burden, clinical status, and echocardiographic severity, and decline progressively with adulticide therapy. Integration of NT-proBNP into diagnostic and therapeutic protocols may enhance management of heartworm-infected dogs with suspected PH.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"18 1","pages":"313"},"PeriodicalIF":3.5,"publicationDate":"2025-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12312376/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144760762","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Individual host factors and co-infections affect the probability and excretion intensity of endoparasite infections in dairy cows.","authors":"Anna Sophie Hecker, Marie-Kristin Raulf, Sven König, Katharina May, Christina Strube","doi":"10.1186/s13071-025-06974-x","DOIUrl":"10.1186/s13071-025-06974-x","url":null,"abstract":"<p><strong>Background: </strong>Endoparasite infections cause economic losses in dairy farming. Understanding the factors that influence endoparasite prevalence and egg/oocyst excretion is essential for effective parasite control. Environmental and management factors play an important role at herd level; however, factors related to the individual cow, such as the parity number or lactation stage, also contribute to infection. In addition, it is still unclear to what extent co-infections with other endoparasites influence prevalence and egg/oocyst excretion rates.</p><p><strong>Methods: </strong>Faecal samples from 1,126 cows from 24 dairy herds were copromicroscopically examined for endoparasite infections. Hurdle models were applied to test the effect of parity number, lactation stage and co-infections on the probability and intensity of egg/oocyst excretion of strongyles, Fasciola hepatica, rumen flukes and coccidia.</p><p><strong>Results: </strong>Strongyle eggs were present in all herds and 45.9% of individual cows, F. hepatica eggs in 75.0% of herds and 9.9% of cows, rumen fluke eggs in 62.5% of herds and 26.5% of cows and coccidian oocysts in 91.7% of herds and 18.7% of cows. Eggs of Moniezia spp., Trichuris spp. and Capillaria spp. were detected sporadically. Model analysis revealed that the probability of strongyle egg excretion decreased after the first parity, presumably as a result of developing immunity, yet an increase was observed after the fourth parity. With increasing parity number, excretion probability of F. hepatica and excretion intensity of rumen flukes increased. Coccidian oocysts excretion was highest in first-parity cows. The lactation stage affected strongyle egg excretion, with the highest probability in early lactation, possibly linked to the negative energy balance in this period. Strongyle co-infections increased the probability of coccidian oocyst excretion (P = 0.008), and coccidian co-infections increased both the probability (P = 0.011) and intensity (P = 0.007) of strongyle egg excretion. Furthermore, coccidian co-infections were associated with a decreased excretion intensity of rumen fluke eggs (P = 0.022).</p><p><strong>Conclusions: </strong>The identification of age groups that are more susceptible to or more likely to spread certain endoparasite taxa and the synergism between strongyle egg and coccidian oocyst excretion can help to implement effective targeted monitoring and control strategies to optimise parasite management in dairy herds.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"18 1","pages":"311"},"PeriodicalIF":3.5,"publicationDate":"2025-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12309137/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144753974","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Proline dehydrogenase, a rate-limiting catabolic enzyme, affecting the growth and pathogenicity of Toxoplasma gondii tachyzoites by regulating the proline metabolism and mitochondrial function of the parasite.","authors":"Xiao-Ling Geng, Jing-Yu Li, Huan-Yu Xu, Jiang-Ping Wu, De-Liang Tao, Jin-Ming Chen, Ying-Ying Fan, Xin Yang, Jun-Ke Song, Guang-Hui Zhao","doi":"10.1186/s13071-025-06966-x","DOIUrl":"10.1186/s13071-025-06966-x","url":null,"abstract":"<p><strong>Background: </strong>The pathogenicity of Toxoplasma gondii is closely associated with its intracellular lytic cycle in host cells. Currently, the mechanisms by which T. gondii completes the lytic cycle remain unclear. The proline metabolism has been reported to be crucial for intracellular growth of pathogens by providing energy and nutrients. However, it remains unclear whether the intracellular growth and pathogenicity of T. gondii are related to proline metabolism.</p><p><strong>Methods: </strong>The gene-edited strains of proline dehydrogenase (Tgprodh) were constructed by using clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9 (CRISPR-Cas9) technology. The effects of the Tgprodh gene on the growth in vitro and pathogenicity in vivo of the tachyzoites for T. gondii were studied through proliferation, plaque, invasion, egress and virulence assays. The effects of the Tgprodh gene on mitochondrial function were studied by using reactive oxygen species (ROS), mitochondrial membrane potential (∆Ψm), adenosine triphosphate (ATP) assay kits, mitochondrial DNA (mtDNA) copy numbers, transmission electron microscopy (TEM) analysis, and reverse transcriptase quantitative polymerase chain reaction (RT-qPCR). The effects of the Tgprodh gene on proline metabolism were studied by using L-proline (L-Pro), L-glutamic acid (L-Glu), L-glutamine (L-Gln) assay kits, and RT-qPCR.</p><p><strong>Results: </strong>TgPRODH, the first rate-limiting enzyme in proline metabolism, was identified to be encoded by T. gondii and localized in the cytoplasm of T. gondii. Deletion of the Tgprodh gene resulted in significant growth inhibition in vitro and reduced pathogenicity in vivo of T. gondii. Further study found that deletion of the Tgprodh gene caused damage to the mitochondrial morphology, decreased membrane potential, mtDNA copy numbers, and the production of ATP and ROS. The expression of genes for maintaining mitochondrial integrity was downregulated in the Tgprodh-knockout strain of T. gondii, while complementation of the Tgprodh gene restored these defects in this parasite. Meantime, the deletion of the Tgprodh gene resulted in the accumulation of proline, reduced the contents of glutamate and glutamine, and affected the expression of genes related to proline catabolism in T. gondii.</p><p><strong>Conclusions: </strong>The present study found the significance of the Tgprodh gene for the intracellular growth and pathogenicity of T. gondii through regulating mitochondrial function and the proline metabolism and provided a novel insight to reveal intracellular survival strategies of T. gondii.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"18 1","pages":"309"},"PeriodicalIF":3.5,"publicationDate":"2025-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12308898/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144743918","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}