Acta Parasitologica最新文献

{"title":"Molecular Detection of Filarioid Nematodes in Bats from the Western Brazilian Amazon","authors":"Jhonatan Henrique Lima da Rocha,&nbsp;Pedro Zanata Lima dos Santos,&nbsp;Cleyton Silva de Araújo,&nbsp;Guilherme Henrique Reckziegel,&nbsp;Deise Kelly Alves da Silva,&nbsp;Laura Kelly Teixeira Veras,&nbsp;Samyly Coutinho de Aguiar Silva,&nbsp;Sérgio Luiz Bessa Luz,&nbsp;Tamyres Izarelly Barbosa da Silva","doi":"10.1007/s11686-026-01398-8","DOIUrl":"10.1007/s11686-026-01398-8","url":null,"abstract":"<div><h3>Purpose</h3><p>Filarial nematodes (Onchocercidae) infect diverse mammals, but their occurrence and molecular diversity in Amazonian bats remain poorly documented. We investigated bat-associated filarioids in urban and peri-urban forest fragments in Rio Branco, Acre, western Brazilian Amazon.</p><h3>Methods</h3><p>Between December 2022 and October 2023, bats were captured with mist nets in five forest fragments and identified morphologically. Blood was screened for microfilariae by thin smear and microhematocrit. A mitochondrial 12 S rRNA fragment (~ 330 bp) was amplified, and PCR-positive products were Sanger sequenced. Consensus sequences were assessed by BLASTn; after alignment and trimming, 300 nucleotide positions were retained for pairwise p-distance analysis and maximum-likelihood phylogenetic inference (HKY + G; 1,000 bootstraps).</p><h3>Results</h3><p>Ninety bats representing 20 species, 13 genera, and four families were captured. Microfilariae were detected in 2/90 bats (2.2%): <i>Artibeus planirostris</i> and <i>Tonatia maresi</i>. UDV06 (PZ124269), from <i>A. planirostris</i>, showed strong affinity with <i>Litomosoides</i>, with ~ 98–99% BLASTn identity, complete query coverage, low divergence, and clustering within the genus. HF17 (PZ124268), from <i>T. maresi</i>, showed only ~ 87–88% identity to available <i>Litomosoides</i> sequences and a markedly divergent phylogenetic position, supporting its conservative treatment as an unresolved member of Onchocercidae.</p><h3>Conclusion</h3><p>These findings document bat-associated filarioid occurrence and molecular diversity in the western Brazilian Amazon. UDV06 is supported as <i>Litomosoides</i> at the genus level, whereas HF17 remains unresolved within Onchocercidae. Additional mitochondrial, particularly <i>cox1</i>, and nuclear markers are needed for improved taxonomic resolution.</p></div>","PeriodicalId":6932,"journal":{"name":"Acta Parasitologica","volume":"71 5","pages":""},"PeriodicalIF":1.5,"publicationDate":"2026-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13550097/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148904735","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Deferiprone Modulates Ferroptosis to Protect Macrophages and Liver during Neospora caninum Infection","authors":"Zijun Zhu,&nbsp;Xi Jiang,&nbsp;Rongsheng Huang,&nbsp;Xin Guo,&nbsp;Yiwen Wang,&nbsp;Tingting Liu,&nbsp;Jiaxuan Wang,&nbsp;Jing Huang,&nbsp;Wenlong Huang,&nbsp;Dezhi Zhang,&nbsp;Qianyong Li,&nbsp;Shengfeng Chen,&nbsp;Zhengtao Yang,&nbsp;Quan Liu,&nbsp;Zhengkai Wei","doi":"10.1007/s11686-026-01343-9","DOIUrl":"10.1007/s11686-026-01343-9","url":null,"abstract":"<div><h3>Background</h3><p><i>Neospora caninum</i> (<i>N. caninum</i>), an obligate intracellular apicomplexan parasite, infects nucleated cells across diverse mammalian hosts, resulting in severe clinical outcomes, including reproductive failure (abortion, stillbirth) and neurological impairment. Ferroptosis, an iron-dependent, non-apoptotic cell death pathway characterized by excessive lipid peroxidation, is closely associated with disrupted iron metabolism and oxidative stress. Deferiprone (DFP), a clinically approved iron chelator, is widely used in the treatment of iron overload disorders such as β-thalassemia, Alzheimer’s disease, and superficial hemosiderosis. While ferroptosis has been implicated in various disease states, its role in <i>N. caninum</i> infection remains unknown.</p><h3>Methods</h3><p>This study established in vitro and in vivo infection models to investigate the role of ferroptosis in <i>N. caninum</i> pathogenesis and the protective mechanism of DFP. In vitro, RAW 264.7 were infected with <i>N. caninum</i> and treated with DFP, followed by comprehensive assessment of reactive oxygen species (ROS), glutathione (GSH) levels, intracellular iron content, GPX4 expression, and parasite proliferation via qPCR. In vivo, C57BL/6 mice were intraperitoneally inoculated with 1 × 10^{^7} tachyzoites and orally administered DFP for seven days. Body weight, food intake, hepatic pathology, oxidative stress markers (GSH and MDA), iron levels, and ferroptosis-related gene expression (GPX4, FTH1, and TRF) were monitored.</p><h3>Results</h3><p>Our in vitro findings demonstrated that <i>N. caninum</i> infection significantly elevated ROS production and intracellular iron accumulation while depleting GSH and suppressing GPX4 transcription—hallmarks of ferroptosis. Remarkably, DFP treatment reversed these effects, restoring redox balance and protecting host tissue, not host control of infection. In vivo, DFP alleviated <i>N. caninum</i>-induced hepatic ferroptosis, as evidenced by normalized iron homeostasis, upregulated GPX4 and ferritin expression, and reduced histopathological damage. However, DFP exacerbated weight loss, suggesting a potential trade-off between ferroptosis inhibition and metabolic adaptation.</p><h3>Conclusions</h3><p>In summary, these results establish ferroptosis as a critical pathogenic mechanism in <i>N. caninum</i> infection and highlight DFP’s dual role in mitigating oxidative injury while possibly impairing host metabolic responses. Our findings provide novel insights into iron-targeted therapeutic strategies for combating intracellular parasitic infections, paving the way for future investigations into optimizing host-directed antiparasitic interventions.</p></div>","PeriodicalId":6932,"journal":{"name":"Acta Parasitologica","volume":"71 5","pages":""},"PeriodicalIF":1.5,"publicationDate":"2026-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148904580","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecular Characterization and Genetic Diversity of Ehrlichia canis in Naturally Infected Dogs from the Unaí Microregion, Minas Gerais, Brazil","authors":"Aroldo de Souza Junior,&nbsp;Jônathan David Ribas Chagas,&nbsp;Isadora dos Santos Dias,&nbsp;Ellen Meireles Brandão,&nbsp;Luiza Sena Chalub,&nbsp;Laura Marques Batista,&nbsp;Julia Oliveira Amaral,&nbsp;Jenevaldo Barbosa da Silva,&nbsp;Matheus Dias Cordeiro,&nbsp;Claudia Bezerra da Silva,&nbsp;Bruna de Azevedo Baêta","doi":"10.1007/s11686-026-01389-9","DOIUrl":"10.1007/s11686-026-01389-9","url":null,"abstract":"<div><p><i>Ehrlichia canis</i> is an obligate intracellular bacterium responsible for canine monocytic ehrlichiosis and is widely distributed in tropical and subtropical regions. This study investigated the occurrence and genetic diversity of <i>E. canis</i> in naturally infected dogs from the Unaí microregion, Minas Gerais, Brazil, using the <i>trp19</i>, <i>p28</i>, and <i>trp36</i> genes as molecular markers. A total of 386 whole blood samples were initially screened by conventional PCR targeting the Anaplasmataceae 16S rRNA gene, yielding 38 positive samples (9.8%). Subsequent PCR targeting the <i>E. canis trp19</i> gene confirmed infection in 21 samples (5.4%). Among these, 12 samples were positive for the p28 gene and eight for the <i>trp36</i> gene. Sequence analysis of <i>p28</i> revealed high nucleotide identity (99.27–99.88%) with reference strains and amino acid substitutions. Haplotype network analysis identified nine <i>p28</i> haplotypes, indicating substantial intraspecific genetic diversity. Analysis of the <i>trp36</i> gene demonstrated the co-circulation of Brazilian and American genogroups, with variation in tandem repeat copy number. These findings reveal a genetically heterogeneous <i>E. canis</i> population in the Unaí microregion and provide evidence of the co-circulation of distinct lineages. The combined use of multiple molecular markers improved the characterization of the circulating strains and contributes to a better understanding of the molecular epidemiology and population diversity of <i>E. canis</i> in Brazil.</p></div>","PeriodicalId":6932,"journal":{"name":"Acta Parasitologica","volume":"71 5","pages":""},"PeriodicalIF":1.5,"publicationDate":"2026-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13550018/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148904589","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Epidemiological and Clinical-Laboratorial Profile of Schistosomiasis in an Endemic Urban Area in Pernambuco, Brazil","authors":"Maria Eduarda da Silva Pereira,&nbsp;Walter Lins Barbosa Júnior,&nbsp;Diego Leandro Reis da Silva Fernandes,&nbsp;Ana Lúcia Coutinho Domingues,&nbsp;Virginia Maria Barros de Lorena,&nbsp;Elainne Christine de Souza Gomes","doi":"10.1007/s11686-026-01384-0","DOIUrl":"10.1007/s11686-026-01384-0","url":null,"abstract":"<div><p>In Brazil, although schistosomiasis mansoni is estimated to present positivity and severe infection rates below 5% in endemic states, there are inequalities among regions represented by municipalities showing moderate and high positivity rates. This study aimed to describe the epidemiological and clinical-laboratory profiles of an urban area. A cross-sectional ecological study was conducted in Novo Horizonte, Jaboatão dos Guararapes, state of Pernambuco, Brazil. The study area was mapped using a GPS receiver, a parasitological survey was performed (using Kato-Katz and Hoffman, Pons e Janer techniques), and clinical evaluations were conducted using upper abdominal ultrasonography (US) and socioenvironmental conditions related to household and peridomestic environments were performed. Based on parasitological techniques, 23.68% positivity rate was found, 66.67% male individuals, and a 284.5 eggs per gram mean. Using molecular biology techniques, the prevalence has increased to 28.94%. US was performed in 55 infected and 57 non-infected individuals, of which 31 and 19 presented periportal fibrosis (PPF), respectively. Infected individuals with PPF presented a larger portal vein diameter and had a higher frequency in males. The Novo Horizonte showed a moderate positivity rate within a municipality considered to have low endemicity. The results highlight the need to carry out frequent parasitological surveys, increased active case finding and the use of other more sensitive diagnosis methods. More targeted studies are needed to better understand the dynamics of schistosomiasis transmission in this locality, as well as the health consequences for exposed and infected individuals.</p></div>","PeriodicalId":6932,"journal":{"name":"Acta Parasitologica","volume":"71 5","pages":""},"PeriodicalIF":1.5,"publicationDate":"2026-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13550039/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148904575","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pathological Study on Differences in Growth Patterns Between Hepatic Alveolar Echinococcosis and Hepatocellular Carcinoma","authors":"Fuzhong Fang,&nbsp;Zhiyi Lin,&nbsp;Jiang Li,&nbsp;Fuxin Jiao,&nbsp;Yongguo Zhang,&nbsp;Qian Chen,&nbsp;Ming Wang,&nbsp;Zirui Xin,&nbsp;Yuan Yao,&nbsp;Chunxia Hu,&nbsp;Jiayu Zhou,&nbsp;Haofei Tian,&nbsp;Ningjun Xu,&nbsp;Peihang Yue,&nbsp;Yanyu Yang,&nbsp;Lola B. Makhmudova,&nbsp;Mahfuz Ali,&nbsp;Amit J. Pathar,&nbsp;Xinyu Peng,&nbsp;Hongwei Zhang","doi":"10.1007/s11686-026-01387-x","DOIUrl":"10.1007/s11686-026-01387-x","url":null,"abstract":"<div><h3>Background</h3><p>Hepatic alveolar echinococcosis (HAE) is frequently described as a “parasitic cancer” because of its tumor-like growth characteristics; however, whether it truly exhibits carcinoma-like invasive behavior remains unclear. In this study, we performed a systematic histopathological comparison of HAE and hepatocellular carcinoma (HCC) to delineate differences in their growth patterns. Our findings provide a new theoretical basis for optimizing clinical management strategies for HAE.</p><h3>Methods</h3><p>Lesional tissue samples were obtained from patients with HAE and HCC for histological slide preparation. The pathological features of both conditions were then systematically examined by light microscopy to assess differences in their growth patterns.</p><h3>Results</h3><p>(1) Within lesional tissues, vascular structures in HAE were predominantly residual vessels that were encased and compressed by the advancing lesion, rather than newly formed vessels; in contrast, clustered neovascularization predominated in HCC. Similarly, in HAE, bile ducts represent residual normal bile duct structures rather than newly formed bile ducts. In HCC, only a small percentage of cases show subtle proliferation of small bile ducts within the tumor stroma. Neural involvement was comparable between the two conditions: perineural encasement was observed in 12.6% of HAE cases versus 8.4% of HCC cases (<i>P</i> = 0.319), and neural invasion occurred in 3.9% and 1.9% of cases, respectively (<i>P</i> = 0.644). (2) At the interface between lesional and hepatic tissues, the fibrous capsule remained intact without evidence of infiltration in HAE. In contrast, cancer cell infiltration was observed in 80.4% of HCC cases (<i>P</i> &lt; 0.05). HAE showed no direct invasion of the hepatic parenchyma, consistent with preservation of fibrous septa, whereas septal disruption with direct parenchymal invasion along sinusoids was identified in 17.8% of HCC cases (<i>P</i> &lt; 0.05). The incidence of vascular compression was comparable between the two groups (HAE: 20.4% vs. HCC: 16.8%; <i>P</i> = 0.507). However, vascular invasion was rare in HAE (1.9%) but occurred in 31.8% of HCC cases (<i>P</i> &lt; 0.05). No significant differences were observed in bile duct compression (HAE: 16.5% vs. HCC: 10.3%; <i>P</i> = 0.185) or bile duct invasion (HAE: 1.9% vs. HCC: 3.7%; <i>P</i> = 0.714). (3) At the lesional surface, HAE lesions adjacent to the hepatic capsule were consistently covered by dense fibrous tissue, with no evidence of capsular invasion. In contrast, direct capsular invasion was observed in 17.8% of HCC cases (<i>P</i> &lt; 0.05).</p><h3>Conclusion</h3><p>From a pathological perspective, the growth pattern of HAE differs markedly from the invasive growth of HCC. HAE exhibits an expansive growth pattern, always encased by a fibrous capsule, which provides a theoretical foundation for the complete surgical resection of the lesion.</p></div>","PeriodicalId":6932,"journal":{"name":"Acta Parasitologica","volume":"71 5","pages":""},"PeriodicalIF":1.5,"publicationDate":"2026-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148904715","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Population and Component Community Descriptors of Monopisthocotyla Parasitizing Triportheus spp. (Actinopterygii: Triportheidae) in the Tocantins-Araguaia River Basin, Brazil","authors":"Dennisiane de Jesus Saraiva,&nbsp;Andréa Pereira da Costa,&nbsp;Diego Carvalho Viana,&nbsp;Rita de Maria Seabra Nogueira,&nbsp;Simone Chinicz Cohen","doi":"10.1007/s11686-026-01372-4","DOIUrl":"10.1007/s11686-026-01372-4","url":null,"abstract":"<div><h3>Purpose</h3><p>Monopisthocotyla constitute a diverse group of ectoparasites of Neotropical fish and are recognized as important bioindicators of environmental conditions in aquatic ecosystems. Despite the high biodiversity of the Tocantins–Araguaia basin, studies simultaneously describing the population descriptors and component communities of these parasites in fish of the genus <i>Triportheus</i> are still scarce. This study aimed to characterize the population and component community descriptors of Monopisthocotyla parasitizing <i>Triportheus albus</i> and <i>Triportheus trifurcatus</i> in the Tocantins River, Maranhão, Brazil. </p><h3>Methods</h3><p>A total of 262 hosts were examined (69 <i>T. albus</i> and 193 <i>T. trifurcatus</i>). Parasites were collected from the gills, morphologically identified, and evaluated for prevalence, mean intensity, mean abundance, and distribution pattern. Component communities were characterized using species richness, Shannon diversity, Pielou’s evenness, Simpson’s diversity and dominance, and Berger–Parker dominance. </p><h3>Results</h3><p><i>Triportheus trifurcatus</i> showed higher richness, diversity, and evenness, while <i>T. albus</i> displayed higher dominance, mainly due to the high proportional abundance of <i>Jainus</i> spp. Most parasite populations showed an aggregated distribution pattern, and host-related factors exerted limited influence on parasite abundance and richness. The findings demonstrate differences in the organization of component communities between the two host species. </p><h3>Conclusions</h3><p>The combined use of population and component community descriptors improved the understanding of the ecological organization of Monopisthocotyla communities parasitizing Neotropical fish. These findings provide baseline information for future biodiversity and environmental monitoring studies in the Tocantins-Araguaia River basin.</p></div>","PeriodicalId":6932,"journal":{"name":"Acta Parasitologica","volume":"71 5","pages":""},"PeriodicalIF":1.5,"publicationDate":"2026-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13550041/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148904796","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ticks Recovered from Opportunistically Examined Greater Grisons (Galictis vittata) in Veracruz, Mexico","authors":"Mariemma G. Escorcia-Quintana,&nbsp;Carlos D. Pérez-Brígido,&nbsp;Héctor M. Zazueta-Islas,&nbsp;Adair Caro-Macin,&nbsp;Marlene Solís-Cortés,&nbsp;Estefania Grostieta,&nbsp;Carlos I. Miranda-Caballero,&nbsp;Juan M. Pech-Canché,&nbsp;Víctor Sánchez-Cordero,&nbsp;Ángel Rodríguez-Moreno,&nbsp;Arturo Serrano-Solis,&nbsp;Celina Naval-Ávila,&nbsp;Beatriz Salceda-Sánchez,&nbsp;Roger I. Rodríguez-Vivas,&nbsp;José L. Bravo-Ramos,&nbsp;Sokani Sánchez-Montes","doi":"10.1007/s11686-026-01385-z","DOIUrl":"10.1007/s11686-026-01385-z","url":null,"abstract":"<div><h3>Background</h3><p>Information regarding ectoparasites associated with the greater grison (<i>Galictis vittata</i>) remains scarce throughout most of its geographic range, particularly in Mexico. Previous reports of tick parasitism in this mustelid are limited and restricted mainly to isolated records from Central and South America. In the present study, ticks recovered from two <i>G. vittata</i> individuals from Veracruz, Mexico, were identified using morphological and molecular approaches, and screened for selected bacterial microorganisms.</p><h3>Methods</h3><p>Two <i>G. vittata</i> from northern Veracruz, Mexico, were examined for ectoparasites. Ticks were morphologically identified and representative specimens were molecularly characterized by amplification and sequencing of a partial mitochondrial 16S rDNA fragment. Additionally, PCR assays targeting members of the genera <i>Anaplasma, Bartonella, Borrelia, Coxiella, Ehrlichia, Francisella,</i> and <i>Rickettsia</i> were performed.</p><h3>Results</h3><p>A total of 68 adult ticks was recovered, including <i>Amblyomma ovale</i> (4 males, 6 females), <i>Amblyomma mixtum</i> (1 male), and <i>Amblyomma auricularium (15</i> males, 42 females). Molecular analyses supported the identification of <i>A. mixtum</i> and <i>A. ovale</i>, whereas sequences obtained from specimens morphologically assigned to <i>A. auricularium</i> clustered within <i>Amblyomma parvum</i>. Two <i>A. ovale</i> specimens tested positive <i>for Francisella</i>-like endosymbionts showing 99% identity with sequences previously reported from South America. No DNA of <i>Anaplasma, Bartonella, Borrelia, Coxiella burnetii, Ehrlichia</i>, or <i>Rickettsia</i> was detected.</p><h3>Conclusion</h3><p>The present study expands the currently available information on ticks recovered from <i>G. vittata</i> in Mexico. Although based on opportunistic sampling, these findings provide baseline information for future studies on tick-host associations in wild carnivores from the Neotropical region.</p></div>","PeriodicalId":6932,"journal":{"name":"Acta Parasitologica","volume":"71 5","pages":""},"PeriodicalIF":1.5,"publicationDate":"2026-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148837983","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Parasitic Helminths Associated with Two Species of Serrasalmus Lacepède, 1803 in the Neotropical Region","authors":"Isabela Sales Quagliato,&nbsp;Wagner Toshio Hasuike,&nbsp;Reinaldo José da Silva,&nbsp;Daniel Rodrigues Blanco,&nbsp;Ricardo Massato Takemoto,&nbsp;Heleno Brandão","doi":"10.1007/s11686-026-01376-0","DOIUrl":"10.1007/s11686-026-01376-0","url":null,"abstract":"<div><h3>Objectives</h3><p>This study investigated the helminth fauna of <i>Serrasalmus maculatus</i> and <i>Serrasalmus marginatus</i> in a protected area (Santa Helena Biological Refuge) and in the lower São Francisco Falso River, Brazil. The main objective was to compare the parasitic helminth fauna of these species between the areas of occurrence and to develop an updated list of the recorded parasite species.</p><h3>Methods</h3><p>Fifty individuals of each host species were collected between November 2018 and November 2019 using gillnets.</p><h3>Results</h3><p>Twelve parasitic taxa were identified, two of which were recorded for the first time: <i>Spinoxyuris</i> sp. in <i>S. marginatus</i> and <i>Raphidascaris</i> sp. (larvae) in <i>S. maculatus</i>. The most abundant parasite species in both hosts and sampling areas were <i>Austrodiplostomum compactum</i> metacercariae and <i>Rhinoxenus arietinus</i>. The helminth fauna differed among the hosts, with <i>S. marginatus</i> parasitized with Philometridae gen. et sp., <i>Spinoxyuris</i> sp., Digenea gen. et sp.1 and et sp. 2, while <i>S. maculatus</i> hosted <i>Ichthyouris brasiliensis</i>, <i>Raphidascaris</i> sp., and exclusively <i>Anacanthorus</i> sp., <i>Notothecium</i> sp., and <i>Rhinoxenus euryxenus</i>.</p><h3>Conclusion</h3><p>This study provides a revised list of helminths associated with <i>S. maculatus</i> and <i>S. marginatus</i>, including new records of hosts and geographic regions. Comparative analysis highlights differences in the richness and composition of parasite communities between the two Serrasalmidae species, contributing to the understanding of host-parasite relationships in Neotropical freshwater ecosystems.</p></div>","PeriodicalId":6932,"journal":{"name":"Acta Parasitologica","volume":"71 5","pages":""},"PeriodicalIF":1.5,"publicationDate":"2026-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13503486/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148811712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Diversity of Dipteran Vectors Associated with Different Mammalian Hosts in a Peri-Urban Zoological Garden in NW Spain","authors":"Alejandro Polina,&nbsp;Yasmina Martínez-Barciela,&nbsp;Josefina Garrido","doi":"10.1007/s11686-026-01375-1","DOIUrl":"10.1007/s11686-026-01375-1","url":null,"abstract":"<div><h3>Purpose</h3><p>This study aims to characterise the different dipteran vector communities present at a peri-urban zoological and to explore differences in community composition among the different mammalian hosts, and to assess their potential epidemiological risk.</p><h3>Methods</h3><p>Five animal enclosures were sampled and compared using CDC light traps equipped with white lights (WL) and ultraviolet traps (UV), used alternatively over five weeks in the summer of 2025.</p><h3>Results</h3><p>A total of 598 dipteran vectors were collected in the present study: 495 mosquitoes belonging to nine species; 73 sand flies to one species; and 30 biting midges (<i>Culicoides</i> spp.) to six species. Generalized linear models (GLMs) showed a strong influence of larger mammals (sheep IRR = 7.28; bear IRR = 6.35) on mosquito abundance, registering more captures in comparison to meerkats (reference); as well as of the type of light, as UV captured up to 2.54 more specimens than WL. Sand fly abundance was mainly defined by the nearest host, as sheep (IRR = 49.52) and bear (IRR = 13.00) enclosures captured more specimens than the meerkat area. The non-metric multidimensional scaling ordination (nMDS) for the mosquito community showed that the animal enclosure explained 41% of the variance independently. Screening for bluetongue virus, epizootic haemorrhagic disease virus, and <i>Leishmania infantum</i> yielded negative results.</p><h3>Conclusions</h3><p>The zoological garden of Vigo provides suitable conditions for the development of different vector species of mosquitoes, sand flies and biting midges, including invasive species such as <i>Ae. albopictus</i>. In addition, differences in vector composition were observed among host enclosures, providing valuable insights into vector ecology.</p></div>","PeriodicalId":6932,"journal":{"name":"Acta Parasitologica","volume":"71 5","pages":""},"PeriodicalIF":1.5,"publicationDate":"2026-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13503408/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148811664","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Antibody Recognition and Functional Activity Against a Conserved Trypanosoma cruzi Peptide and Its Natural Variants in Kinetoplastids","authors":"Juan Diego Zuluaga,&nbsp;Fanny Guzmán,&nbsp;Juan Carlos Santos-Barbosa,&nbsp;Liseth Vanessa Gonzalez,&nbsp;M. Carmen Thomas,&nbsp;Manuel Carlos López,&nbsp;Adriana Cuéllar,&nbsp;Concepción J. Puerta,&nbsp;John M. González","doi":"10.1007/s11686-026-01381-3","DOIUrl":"10.1007/s11686-026-01381-3","url":null,"abstract":"<div><h3>Purpose</h3><p>The TcTLE peptide (TLEEFSAKL), located at the amino-terminus of the <i>Trypanosoma cruzi</i> Kinetoplastid Membrane Protein-11 (KMP-11), induces robust humoral and cellular immune responses, suggesting its potential for serological diagnostics or immunoprophylaxis. However, natural variants of this sequence exist in <i>Leishmania</i> spp. This study aims to assess the humoral specificity toward this epitope.</p><h3>Methods</h3><p>KMP-11 sequences were retrieved from the UniProtKB database. Multiple sequence alignment was conducted using the CLUSTALW alignment tool. In silico analysis of the peptides was performed using I-TASSER. Alanine scan derivates as well as chemically synthesized TcTLE, TcY (T<b><u>Y</u></b>EEFSAKL), and TcYA (T<b><u>Y</u></b>EEF<b><u>A</u></b>AKL) peptides were tested by ELISA using both a monoclonal antibody (mAb) and polyclonal rabbit sera raised against TcTLE. Additional analyses included indirect immunofluorescence assay (IFAT) and flow cytometry with <i>T. cruzi</i> epimastigotes (TcTLE), <i>Leishmania amazonensis</i> (TcY), and <i>Leishmania panamensis</i> (TcYA) promastigotes. Invasion assays were carried out with susceptible cells and <i>T. cruzi</i> trypomastigote CFSE labeling.</p><h3>Results</h3><p>By ELISA, both mAb and polyclonal sera recognized TcY but showed minimal reactivity to TcYA. Alanine scanning revealed that residue 2 is not critical for antibody recognition. In IFAT, the mAb failed to bind fixed parasites, whereas in flow cytometry it bound live <i>T. cruzi</i> epimastigotes but not <i>Leishmania</i> promastigotes. The anti-TcTLE mAb significantly reduced <i>T. cruzi</i> cell invasion in vitro.</p><h3>Conclusion</h3><p>Overall, although the TcY variant was recognized in vitro, antibodies to TcTLE did not detect parasites expressing the KMP-11 variants, indicating that true cross-reactivity with <i>Leishmania</i> is unlikely.</p></div>","PeriodicalId":6932,"journal":{"name":"Acta Parasitologica","volume":"71 5","pages":""},"PeriodicalIF":1.5,"publicationDate":"2026-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148811718","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}