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1.
Semina cienc. biol. saude ; 45(2): 45-56, jul./dez. 2024. tab; ilus
Artigo em Inglês | LILACS | ID: biblio-1554899

RESUMO

Enteroparasitosis are diseases caused by parasitic agents present in the environment and in the gastrointestinal tract of living beings. In addition, they are still considered neglected diseases, but of great importance for public health, especially when they are related to secondary infections and currently their co-infection profile with COVID-19. The interaction of protozoa and/or helminths with the SARS-CoV-2 virus is timely and its signs and symptoms are confused with other pathogen relationships. In this way, this study aims to correlate the incidence of enteroparasitosis and COVID-19, in the pandemic period from 2020 to April 2022. This is a documentary and exploratory study of secondary data from laboratory tests of patients who were treated and diagnosed with COVID-19 and enteroparasitosis at Hospital Doutor Cloves Bezerra Cavalcante, Municipal Hospital of Bananeiras, Paraíba, Brazil. In the analysis of the database, a significant increase of approximately 48.85% in the incidence of COVID-19 cases from 2020 to 2021 stands out, remaining high until 2022. In contrast, cases of enteroparasites peaked at 48.74% in 2021, followed by an average reduction of 23.12%, with a deviation of 1.49%, in relation to the years 2020 and 2022. It was concluded that COVID-19 is predominantly associated with an increase in secondary infections, highlighting the crucial need to promote health education, improve basic sanitation and guarantee access to health services as essential components in combating the increase in parasitic infections, especially those related to viral pathologies.


As enteroparasitoses são enfermidades originadas por agentes parasitários presentes no meio ambiente e no trato gastrointestinal dos seres vivos. Ademais, ainda são consideradas doenças negligenciadas, porém de grande importância para a saúde pública, em especial, quando estão relacionadas com infecções secundárias e atualmente seu perfil de coinfecção com a COVID-19. A interação de protozoários e/ou helmintos com o vírus SARS-CoV-2 é oportuna e seus sinais e sintomas são confundidos com outras relações de patógenos. Desta maneira, este estudo visa correlacionar a incidência de enteroparasitoses e COVID-19, no período pandêmico de 2020 a abril de 2022. Trata--se de uma pesquisa documental e exploratória, de dados secundários dos exames laboratoriais de pacientes que foram atendidos e diagnosticados com COVID-19 e enteroparasitoses no Hospital Doutor Cloves Bezerra Cavalcante, Hospital Municipal de Bananeiras, Paraíba, Brasil. Na análise da base de dados, destaca-se um aumento significativo de aproximadamente 48,85% na incidência de casos de COVID-19 de 2020 a 2021, mantendo-se elevado até 2022. Em contraste, os casos de enteroparasitas atingiram um pico de 48,74% em 2021, seguido por uma redução média de 23,12%, com um desvio de 1,49%, em relação aos anos de 2020 e 2022. Conclui-se que a COVID-19 está predominantemente associada ao aumento de infecções secundárias, destacando a necessidade crucial de promover a educação em saúde, melhorar o saneamento básico e garantir o acesso aos serviços de saúde como componentes essenciais no combate ao aumento de infecções parasitárias, especialmente aquelas relacionadas a patologias virais.


Assuntos
Humanos , Masculino , Feminino
2.
Infect Drug Resist ; 17: 3769-3775, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39229329

RESUMO

Purpose: The incidence of visceral leishmaniasis (VL), a global infectious disease, has been on the rise in China's Hebei province. When patients achieve clinical cure, they often do not reach an etiological cure, which may lead to recurrence of the disease. Here, we report a case of visceral leishmaniasis with a negative blood smear and bone marrow cytology. Patients and Methods: A 65-year-old man and bronchoalveolar lavage fluid mNGS. Results: A 65-year-old man developed a chronic fever, anorexia, splenomegaly, and pancytopenia. The blood metagenomic second-generation sequencing (mNGS) revealed Leishmania sequence readings, which led to the diagnosis of VL. After sodium antimony gluconate treatment, the blood smear and bone marrow cytology revealed no Leishmania bodies. However, pancytopenia and respiratory failure did not fully subside, and cardiotoxic damage emerged. The bronchoalveolar lavage fluid (BALF) mNGS was performed to detect the pathogen. Through BALF mNGS, Leishmania sequence was still detectable. Therefore, after the ECG returned to normal, antimony sodium gluconate was administered as a next course of treatment. Conclusion: BALF mNGS may assist in evaluating the therapeutic efficacy of VL with respiratory failure, especially in patients with negative blood and bone marrow cytology.


Accurate detection of visceral leishmaniasis is essential for clinical diagnosis.It is uncommon to use alveolar lavage fluid mNGS in etiological diagnosis.Patient with negative bone marrow cytology may refer to alveolar lavage fluid mNGS.

3.
J Fish Dis ; : e14013, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39239791

RESUMO

Parasites pose significant challenges to aquaculture and fisheries industries. Our study focuses on the Polyonchobothrium magnum and African catfish to address a potential health issue in aquaculture, explore host-parasite interactions that can help develop effective management practices to ensure fish health and industry sustainability. P. magnum was isolated from the stomach of African catfish (Clarias gariepinus) as the primary site of infection, with a prevalence of 10%. Most affected fish were heavily infected (8 out of 10). Infection was confirmed by sequencing the PCR-targeted region of the nicotinamide adenine dinucleotide dehydrogenase subunit 1 (ND1) gene, along with light and scanning electron microscopes. The parasite had an elongated scolex with deep bothria, a prominent apical disc wider than the scolex itself, and a four-lobed appearance. The scolex contained a central rostellum divided into two semicircles, bearing 26-30 hooks, with an average of 28. The apical disc had large hooks arranged in four quadrants, with 6-8 hooks each, averaging 7 per quadrant. No neck was observed. Phylogenetic analysis of our sequence showed a 100% match with isolates from Guangzhou, China. In infected fish, the anterior kidney showed increased expression levels of nuclear factor kappa B and lysozyme, but decreased levels of in major histocompatibility complex antigen II. Plasma analysis revealed a significant drop in superoxide dismutase, a rise in interleukin-1 beta, and lower IgM levels compared to non-infected controls. Non-infected fish displayed greater gut microbiota diversity, with dominant families including Moraxellaceae, Enterobacteriaceae, Fusobacteriaceae, and Caulobacteraceae, and prevalent genera such as Acinetobacter, Cetobacterium, and Brevundimonas. In contrast, infected fish exhibited very low diversity, with significantly higher proportions of Enterobacteriaceae (45.99%) and Aeromonadaceae (41.79%) compared to non-infected fish, which had 13.76% and 3.64% respectively. Cetobacterium somerae was prevalent in non-infected fish, while infected fish harboured Aeromonas fluvialis, Plesiomonas shigelloides, and Gallaecimonas xiamenensis. Overall, P. magnum disrupted the immune status and gut microbiota of the host, thereby impacting its health.

4.
Parasit Vectors ; 17(1): 381, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39242536

RESUMO

BACKGROUND: Trypanosoma cruzi is transmitted to humans by hematophagous bugs belonging to the Triatominae subfamily. Its intra-vectorial cycle is complex and occurs exclusively in the insect's midgut. Dissecting the elements involved in the cross-talk between the parasite and its vector within the digestive tract should provide novel targets for interrupting the parasitic life cycle and affecting vectorial competence. These interactions are shaped by the strategies that parasites use to infect and exploit their hosts, and the host's responses that are designed to detect and eliminate parasites. The objective of the current study is to characterize the impact of T. cruzi establishment within its vector on the dynamics of its midgut. METHODS: In this study, we evaluated the impact of T. cruzi infection on protein expression within the anterior midgut of the model insect Rhodnius prolixus at 6 and 24 h post-infection (hpi) using high-throughput quantitative proteomics. RESULTS: Shortly after its ingestion, the parasite modulates the proteome of the digestive epithelium by upregulating 218 proteins and negatively affecting the expression of 11 proteins involved in a wide array of cellular functions, many of which are pivotal due to their instrumental roles in cellular metabolism and homeostasis. This swift response underscores the intricate manipulation of the vector's cellular machinery by the parasite. Moreover, a more in-depth analysis of proteins immediately induced by the parasite reveals a pronounced predominance of mitochondrial proteins, thereby altering the sub-proteomic landscape of this organelle. This includes various complexes of the respiratory chain involved in ATP generation. In addition to mitochondrial metabolic dysregulation, a significant number of detoxifying proteins, such as antioxidant enzymes and P450 cytochromes, were immediately induced by the parasite, highlighting a stress response. CONCLUSIONS: This study is the first to illustrate the response of the digestive epithelium upon contact with T. cruzi, as well as the alteration of mitochondrial sub-proteome by the parasite. This manipulation of the vector's physiology is attributable to the cascade activation of a signaling pathway by the parasite. Understanding the elements of this response, as well as its triggers, could be the foundation for innovative strategies to control the transmission of American trypanosomiasis, such as the development of targeted interventions aimed at disrupting parasite proliferation and transmission within the triatomine vector.


Assuntos
Doença de Chagas , Insetos Vetores , Mitocôndrias , Rhodnius , Trypanosoma cruzi , Animais , Rhodnius/parasitologia , Rhodnius/metabolismo , Trypanosoma cruzi/fisiologia , Trypanosoma cruzi/metabolismo , Insetos Vetores/parasitologia , Mitocôndrias/metabolismo , Doença de Chagas/transmissão , Doença de Chagas/parasitologia , Trato Gastrointestinal/parasitologia , Proteômica , Interações Hospedeiro-Parasita , Proteoma
5.
Sci Rep ; 14(1): 20785, 2024 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-39242861

RESUMO

Most host-parasite associations are explained by phylogenetically conservative capabilities for host utilization, and therefore parasite switches between distantly related hosts are rare. Here we report the first evidence of a parasitic spillover of the burrowing sea anemone Edwardsiella carnea from the invasive ctenophore Mnemiopsis leidyi to two scyphozoan hosts: the native Mediterranean barrel jellyfish Rhizostoma pulmo and the invasive Indo-Pacific nomad jellyfish Rhopilema nomadica, collected from the Eastern Mediterranean Sea. Edwardsiella carnea planulae found in these jellyfish were identified using molecular analyses of the mitochondrial 16S and nuclear 18S rRNA genes. Overall, 93 planulae were found on tentacles, oral arms, and inside of the gastrovascular canals of the scyphomedusae, whereas no infection was observed in co-occurring ctenophores. DNA metabarcoding approach indicated seasonal presence of Edwardsiella sp. in the Eastern Mediterranean mesozooplankton, coinciding with jellyfish blooms in the region. Our findings suggest a non-specific parasitic relationship between Edwardsiella carnea and various gelatinous hosts based on shared functionality rather than evolutionary history, potentially driven by shifts in host availability due to jellyfish blooms. This spillover raises questions about the ecological impacts of parasitism on native and invasive scyphozoan hosts and the potential role of Edwardsiella in controlling their populations.


Assuntos
Ctenóforos , Filogenia , Cifozoários , Anêmonas-do-Mar , Animais , Ctenóforos/genética , Cifozoários/microbiologia , Cifozoários/parasitologia , Anêmonas-do-Mar/parasitologia , Interações Hospedeiro-Parasita , RNA Ribossômico 18S/genética , Mar Mediterrâneo , RNA Ribossômico 16S/genética
6.
J Emerg Med ; 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-39245612
7.
Mol Ecol ; : e17523, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39248016

RESUMO

Genetic analyses of host-specific parasites can elucidate the evolutionary histories and biological features of their hosts. Here, we used population-genomic analyses of ectoparasitic seal lice (Echinophthirius horridus) to shed light on the postglacial history of seals in the Arctic Ocean and the Baltic Sea region. One key question was the enigmatic origin of relict landlocked ringed seal populations in lakes Saimaa and Ladoga in northern Europe. We found that that lice of four postglacially diverged subspecies of the ringed seal (Pusa hispida) and Baltic gray seal (Halichoerus grypus), like their hosts, form genetically differentiated entities. Using coalescent-based demographic inference, we show that the sequence of divergences of the louse populations is consistent with the geological history of lake formation. In addition, local effective population sizes of the lice are generally proportional to the census sizes of their respective seal host populations. Genome-based reconstructions of long-term effective population sizes revealed clear differences among louse populations associated with gray versus ringed seals, with apparent links to Pleistocene and Holocene climatic variation as well as to the isolation histories of ringed seal subspecies. Interestingly, our analyses also revealed ancient gene flow between the lice of Baltic gray and ringed seals, suggesting that the distributions of Baltic seals overlapped to a greater extent in the past than is the case today. Taken together, our results demonstrate how genomic information from specialized parasites with higher mutation and substitution rates than their hosts can potentially illuminate finer scale population genetic patterns than similar data from their hosts.

8.
J Hered ; 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39248324

RESUMO

Polyergus kidnapper ants are widely distributed, but relatively uncommon, throughout the Holarctic, spanning an elevational range from sea level to over 3000 m. These species are well known for their obligate social parasitism with various Formica ant species, which they kidnap in dramatic, highly coordinated raids. Kidnapped Formica larvae and pupae become integrated into the Polyergus colony where they develop into adults and perform nearly all of the necessary colony tasks for the benefit of their captors. In California, Polyergus mexicanus is the most widely distributed Polyergus, but recent evidence has identified substantial genetic polymorphism within this species, including genetically divergent lineages associated with the use of different Formica host species. Given its unique behavior and genetic diversity, Polyergus mexicanus plays a critical role in maintaining ecosystem balance by influencing the population dynamics and genetic diversity of its host ant species, Formica, highlighting its conservation value and importance in the context of biodiversity preservation. Here, we present a high-quality genome assembly of P. mexicanus from a sample collected in Plumas County, CA, USA, in the foothills of the central Sierra Nevada. This genome assembly consists of 364 scaffolds spanning 252.31 Mb, with contig N50 of 481,250 kb, scaffold N50 of 10.36 Mb, and BUSCO completeness of 95.4%. We also assembled the genome of the Wolbachia endosymbiont of P. mexicanus - a single, circular contig spanning 1.23 Mb. These genome sequences provide essential resources for future studies of conservation genetics, population genetics, speciation, and behavioral ecology in this charismatic social insect.

9.
Microbiology (Reading) ; 170(9)2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39234940

RESUMO

Queuosine (Q) stands out as the sole tRNA modification that can be synthesized via salvage pathways. Comparative genomic analyses identified specific bacteria that showed a discrepancy between the projected Q salvage route and the predicted substrate specificities of the two identified salvage proteins: (1) the distinctive enzyme tRNA guanine-34 transglycosylase (bacterial TGT, or bTGT), responsible for inserting precursor bases into target tRNAs; and (2) queuosine precursor transporter (QPTR), a transporter protein that imports Q precursors. Organisms such as the facultative intracellular pathogen Bartonella henselae, which possess only bTGT and QPTR but lack predicted enzymes for converting preQ1 to Q, would be expected to salvage the queuine (q) base, mirroring the scenario for the obligate intracellular pathogen Chlamydia trachomatis. However, sequence analyses indicate that the substrate-specificity residues of their bTGTs resemble those of enzymes inserting preQ1 rather than q. Intriguingly, MS analyses of tRNA modification profiles in B. henselae reveal trace amounts of preQ1, previously not observed in a natural context. Complementation analysis demonstrates that B. henselae bTGT and QPTR not only utilize preQ1, akin to their Escherichia coli counterparts, but can also process q when provided at elevated concentrations. The experimental and phylogenomic analyses suggest that the Q pathway in B. henselae could represent an evolutionary transition among intracellular pathogens - from ancestors that synthesized Q de novo to a state prioritizing the salvage of q. Another possibility that will require further investigations is that the insertion of preQ1 confers fitness advantages when B. henselae is growing outside a mammalian host.


Assuntos
Bartonella henselae , Nucleosídeo Q , Nucleosídeo Q/metabolismo , Nucleosídeo Q/genética , Bartonella henselae/genética , Bartonella henselae/metabolismo , Bartonella henselae/enzimologia , RNA de Transferência/genética , RNA de Transferência/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Evolução Molecular , Especificidade por Substrato , Guanina/análogos & derivados
10.
Parasitol Res ; 123(9): 317, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39235636

RESUMO

The spotted seatrout, Cynoscion nebulosus, is a popular game fish in the southeastern USA. It is estimated that nearly 90% of the adult population in South Carolina estuaries are infected in their skeletal muscle by the myxosporean, Kudoa inornata. However, little is known about this parasite's biology, including the distribution and densities of myxospores within tissues of infected fish, which we expect affect the physiology of their hosts. In order to correlate densities with physiological parameters in future studies, we quantified the myxospores density in muscle and characterized the variation among individual fish. Naïve juvenile seatrout was experimentally infected via presumed K. inornata actinospores exposure to raw seawater. A plug of muscle was extracted from two bilaterally symmetrical regions in the epaxial fillet from fresh and frozen carcasses. Variation in density data was calculated both within and among individuals. Within individuals, density counts were compared between left- and right-side biopsies. There was no significant difference between fresh and frozen plugs, and variation among individuals accounted for the greatest proportion of variation at 68.8%, while variation within individuals was substantial at 25.6%. Simulation and correlation tests confirmed that bilaterally symmetrical replicates varied significantly within individuals. When sampled from areas surrounding the initial biopsies, myxospore density estimates were more similar than between sides. Our findings have important implications for sampling design, particularly for studies investigating physiological parameters at the cellular or molecular level in association with parasite infection.


Assuntos
Doenças dos Peixes , Myxozoa , Doenças Parasitárias em Animais , Animais , Myxozoa/fisiologia , Myxozoa/isolamento & purificação , Doenças dos Peixes/parasitologia , Doenças Parasitárias em Animais/parasitologia , South Carolina , Músculo Esquelético/parasitologia , Perciformes/parasitologia , Esporos , Carga Parasitária , Brancos
11.
Infect Dis Poverty ; 13(1): 65, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39256885

RESUMO

BACKGROUND: Combating infectious diseases and halting biodiversity loss are intertwined challenges crucial to ensure global health. Biodiversity can constrain the spread of vector-borne pathogens circulation, necessitating a deeper understanding of ecological mechanisms underlying this pattern. Our study evaluates the relative importance of biodiversity and the abundance of Bulinus truncatus, a major intermediate host for the trematode Schistosoma haematobium on the circulation of this human pathogen at aquatic transmission sites. METHODS: We combined mathematical modelling and a molecular based empirical study to specifically assess the effect of co-infections between S. haematobium and other trematodes within their B. truncatus snail hosts; and B. truncatus abundance at transmission sites, on the production of S. haematobium infective cercariae stages released into the aquatic environment. RESULTS: Our modelling approach shows that more competitive trematode species exploiting B. truncatus as an intermediate host at the transmission site level leads to higher co-infection rates within snail hosts, subsequently reducing the production of S. haematobium cercariae. Conversely, an increase in B. truncatus abundance results in lower co-infection rates, and a higher proportion of S. haematobium cercariae released into the environment. Our empirical data from the field support these findings, indicating a significant negative effect of local trematode species richness (P-value = 0.029; AIC = 14.9) and co-infection rates (P-value = 0.02, AIC = 17.4) on the dominance of S. haematobium based on our GLMM models, while B. truncatus abundance positively influences S. haematobium dominance (P-value = 0.047, AIC = 20.1). CONCLUSIONS: Our study highlights the importance of biodiversity in influencing the transmission of S. haematobium through the effect of antagonistic interactions between trematodes within bulinid snail hosts. This effect intensifies when B. truncatus populations are low, promoting co-infections within snails. In line with the One Health concept, our results suggest that maintaining high level of freshwater biodiversity to sustain global trematode diversity at transmission sites can help reducing the circulation of Schistosoma species locally.


Assuntos
Interações Hospedeiro-Parasita , Schistosoma haematobium , Trematódeos , Animais , Schistosoma haematobium/fisiologia , Trematódeos/fisiologia , Humanos , Esquistossomose Urinária/transmissão , Esquistossomose Urinária/parasitologia , Bulinus/parasitologia , Caramujos/parasitologia , Biodiversidade , Coinfecção/parasitologia , Modelos Teóricos , Cercárias/fisiologia
12.
Int J Parasitol Parasites Wildl ; 25: 100974, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39257917

RESUMO

The Argentine shortfin squid Illex argentinus is one of the most important commercial species for the Argentine fisheries. The understanding of its stock structure is therefore necessary to ensure fishery sustainability and, given the relevance of squids in the regional food web, for biodiversity conservation. An overlap between parasitology and fisheries lies in the use of parasites as biological tags to identify the stock composition of exploited resources, however, the efficiency of this methodology has been questioned for stock assessment in cephalopods. In this work, the value of parasite assemblages of I. argentinus to discriminate between the co-occurring summer spawning stock (SSS) and south patagonic stock (SPS) in a mixing area over the Patagonian continental shelf during summer was evaluated for two cohorts. Five shortfin squid samples corresponding to SSS and SPS were examined for metazoan parasites. The squid size affected the parasite assemblage similarities, conversely, no gender effect on the infracommunities was observed. Multivariate analysis evidenced similarity in parasite assemblage composition and structure between both stocks captured in the mixing area on the same date. This similarity was related to the presence of short-lived trophically transmitted parasites, which are associated with their recently consumed food items and, indirectly, to the oceanographic conditions. The same set of host and environmental variables were identified as the most probable causes of the temporal variability observed in parasite assemblages between SPS cohorts and even intra-cohort. Despite the value of parasites as tags for discriminating squid stocks may have little value when cohabiting stocks are analysed, their variability could serve as a valuable indicator of environmental conditions. The use of parasites as biological tags to discriminate stocks needs to be verified at different spatiotemporal scales, including samples from other non-sympatric stocks in the analyses.

13.
Front Cell Infect Microbiol ; 14: 1451063, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39258252

RESUMO

Background: Transmission-blocking vaccines (TBVs) can effectively prevent the community's spread of malaria by targeting the antigens of mosquito sexual stage parasites. At present, only a few candidate antigens have demonstrated transmission-blocking activity (TBA) potential in P. vivax. Quiescin-sulfhydryl oxidase (QSOX) is a sexual stage protein in the rodent malaria parasite Plasmodium berghei and is associated with a critical role in protein folding by introducing disulfides into unfolded reduced proteins. Here, we reported the immunogenicity and transmission-blocking potency of the PvQSOX in P. vivax. Methods and findings: The full-length recombinant PvQSOX protein (rPvQSOX) was expressed in the Escherichia coli expression system. The anti-rPvQSOX antibodies were generated following immunization with the rPvQSOX in rabbits. A parasite integration of the pvqsox gene into the P. berghei pbqsox gene knockout genome was developed to express full-length PvQSOX protein in P. berghei (Pv-Tr-PbQSOX). In western blot, the anti-rPvQSOX antibodies recognized the native PvQSOX protein expressed in transgenic P. berghei gametocyte and ookinete. In indirect immunofluorescence assays, the fluorescence signal was detected in the sexual stages, including gametocyte, gamete, zygote, and ookinete. Anti-rPvQSOX IgGs obviously inhibited the ookinetes and oocysts development both in vivo and in vitro using transgenic parasites. Direct membrane feeding assays of anti-rPvQSOX antibodies were conducted using four field P. vivax isolates (named isolates #1-4) in Thailand. Oocyst density in mosquitoes was significantly reduced by 32.00, 85.96, 43.52, and 66.03% with rabbit anti-rPvQSOX antibodies, respectively. The anti-rPvQSOX antibodies also showed a modest reduction of infection prevalence by 15, 15, 20, and 22.22%, respectively, as compared to the control, while the effect was insignificant. The variation in the DMFA results may be unrelated to the genetic polymorphisms. Compared to the P.vivax Salvador (Sal) I strain sequences, the pvqsox in isolate #1 showed no amino acid substitution, whereas isolates #2, #3, and #4 all had the M361I substitution. Conclusions: Our results suggest that PvQSOX could serve as a potential P. vivax TBVs candidate, which warrants further evaluation and optimization.


Assuntos
Anticorpos Antiprotozoários , Vacinas Antimaláricas , Malária Vivax , Plasmodium berghei , Plasmodium vivax , Proteínas Recombinantes , Plasmodium vivax/imunologia , Plasmodium vivax/genética , Plasmodium vivax/enzimologia , Animais , Coelhos , Vacinas Antimaláricas/imunologia , Anticorpos Antiprotozoários/imunologia , Malária Vivax/prevenção & controle , Malária Vivax/transmissão , Malária Vivax/imunologia , Plasmodium berghei/imunologia , Plasmodium berghei/genética , Plasmodium berghei/enzimologia , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Camundongos , Escherichia coli/genética , Antígenos de Protozoários/imunologia , Antígenos de Protozoários/genética , Proteínas de Protozoários/imunologia , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Feminino , Humanos , Imunogenicidade da Vacina , Camundongos Endogâmicos BALB C
14.
Ecology ; : e4397, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39223438

RESUMO

Most organisms are at risk of being consumed by a predator or getting infected by a parasite at some point in their life. Theoretical constructs such as the landscape of fear (perception of risk) and nonconsumptive effects (NCEs, costly responses sans predation or infection) have been proposed to describe and quantify antipredator and antiparasite responses. How prey/host species identify and respond to these risks determines their survival, reproductive success and, ultimately, fitness. Most studies to date have focused on either predator-prey or parasite-host interactions, yet habitats and ecosystems contain both parasitic and/or predatory species that represent a complex and heterogenous mosaic of risk factors. Here, we experimentally investigated the behavioral responses of a cactophilic fruit fly, Drosophila nigrospiracula, exposed to a range of species that include parasites (ectoparasitic mite), predators (jumping spiders), as well as harmless heterospecifics (nonparasitic mites, ants, and weevils). We demonstrate that D. nigrospiracula can differentiate between threat and non-threat species, increase erratic movements and decrease velocity in the presence of parasites, but decrease erratic movements and time spent grooming in the presence of predators. Of particular importance, flies could distinguish between parasitic female mites and nonparasitic male mites of the same species, and respond accordingly. We also show that the direction of these NCEs differs when exposed to parasitic mites (i.e., risk of infection) versus spiders (i.e., risk of predation). Given the opposing effects of predation versus infection risk on fly behavior, we discuss potential trade-offs between parasite and predator avoidance behaviors. Our findings illustrate the complexity of risk assessment in a landscape of fear and the fine-tuned NCEs that arise in response. Moreover, this study is the first to examine these behavioral NCEs in a terrestrial system.

15.
Acta Parasitol ; 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39225734

RESUMO

BACKGROUND: Toxoplasma gondii (T. gondii) infects one third of the world's population with significant illness, mainly among immunocompromised individuals and pregnant women. Treatment options for toxoplasmosis are limited which signifies the need for novel, potent, and safe therapeutic options. The goal of this study was to assess the effectiveness of the ethanolic extract of Zingiber officinale (Z. officinale) in treating mice infected with the RH T. gondii strain. MATERIALS AND METHODS: Gas Chromatography/Mass Spectrometry (GC/MS) was used to identify components of ethanolic extract of Z. officinale. A total of 80 mice were randomly allocated into four experimental groups that contained 20 mice each. The first group was left uninfected (uninfected control), while three groups were infected with T. gondii RH virulent strain tachyzoites at 2500 tachyzoites/mouse. One infected group was left untreated (infected, untreated), whereas the other two groups were treated orally with either spiramycin (positive control) or Z. officinale ethanolic extract at doses of 200 mg/kg and 500 mg/kg, respectively for 5 days, starting the day of infection. Ten mice from each group were used to assess mice survival in different groups, whereas the other ten mice in each group were sacrificed on the 5th day post-infectin (dpi) to estimate the treatment efficacy by quantifying liver parasite load, liver function, nitric oxide (NO) production, and levels of antioxidant enzymes. Additionally, histopathological studies were performed to evaluate the therapeutic effect of Z. officinale treatment on toxoplasmosis-induced pathological alterations in liver, brain, and spleen. RESULTS: Treatment with Z. officinale ethanolic extract extended the survival of mice till 9th dpi compared to 7th dpi in infected untreated mice. Higher percentage of mice survived in Z. officinale-treated group compared to spiramycin-treatment group at different time points. Liver parasite loads were significantly lower in Z. officinale extract-treated mice and spiramycin-treated mice compared to infected untreated mice which correlated with significantly lower levels of serum liver enzymes (ALT, AST) and nitric oxide (NO), as well as significantly higher catalase (CAT) antioxidant enzyme activity. Scanning electron microscopy (SEM) examination of tachyzoites from the peritoneal fluid revealed marked damage in tachyzoites from Z. officinale-treated group compared to that from infected untreated mice. Moreover, treatment with Z. officinale ethanolic extract alleviated infection-induced pathological alterations and restored normal tissue morphology of liver, brain, and spleen. CONCLUSION: Our results demonstrated that Z. officinale treatment reduced parasite burden and reversed histopathological and biochemical alterations in acute murine toxoplasmosis. These findings support the potential utility of Z. officinale as a future effective natural therapeutic for toxoplasmosis. Further studies are needed to determine the effective active ingredient in Z. officinale extract that can be further optimized for treatment of toxoplasmosis.

16.
Ecology ; : e4394, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39234933

RESUMO

Parasite-host systems are a good study model for answering ecological and evolutionary questions. In this regard, mistletoes have been increasingly studied in recent decades in both temperate and tropical zones. The genus Phoradendron is a group of American mistletoes that has been studied from different evolutionary and ecological approaches as a model of parasite-host systems. Currently, however, no systematic compilation of the plant species parasitized by these mistletoes is available. To address this issue, we conducted a thorough search and compilation of interactions between mistletoe species of the genus Phoradendron and their hosts. This involved consulting multiple sources, including monographs, digitized herbaria material, and scientific publications. Additionally, we incorporated information regarding the presence records of Phoradendron from the most authoritative databases at the national, continental, and global levels. This process yielded a comprehensive dataset consisting of two independent tables, offering information on the interactions and occurrences of Phoradendron throughout its distribution range in the Americas. The dataset includes the interactions between 159 mistletoe species and 118 hosts at the family level, 379 hosts at the genus level, and 544 hosts at the species level, totaling 2929 interactions between species of the genus Phoradendron and their hosts. This data paper represents an updated compilation of a genus of parasitic plants, with the purpose of making this database of interactions accessible for researchers to address questions at multiple scales and from disciplines as varied as biogeography, ecology, evolution, and epidemiology. We plan to use and expand this database with subsequent studies from the authors. There are no copyright restrictions on the dataset; please cite this data paper when using data from this publication. We also encourage you to contact the authors if you are interested in contributing to this database.

17.
Malar J ; 23(1): 267, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39223522

RESUMO

BACKGROUND: The spread of antimalarial drug resistance parasites is a major obstacle in eliminating malaria in endemic areas. This increases the urgency for developing novel antimalarial drugs with improved profiles to eliminate both sensitive and resistant parasites in populations. The invention of the drug candidates needs a model for sensitive and resistant parasites on a laboratory scale. METHODS: Repeated Incomplete Treatment (RIcT) method was followed in raising the rodent malaria parasite, Plasmodium berghei, resistant to sulfadoxine. Plasmodium berghei were exposed to an adequate therapeutic dose of sulfadoxine without finishing the treatment to let the parasite recover. Cycles of drug treatment and parasite recovery were repeated until phenotypic resistance appeared. RESULTS: After undergoing 3-4 cycles, phenotypic resistance was not yet found in mice treated with sulfadoxine. Nevertheless, the molecular biology of dhps gene (the target of sulfadoxine) was analyzed at the end of the RIcT cycle. There was no mutations found in the gene target. Interestingly, the appearance of gametocytes at the end of every cycle of drug treatment and parasite recovery was observed. These gametocytes later on would no longer extend their life in the RBC stage, unless mosquitoes bite the infected host. This phenomenon is similar to the case in human malaria infections treated with sulfadoxine-pyrimethamine (SP). CONCLUSIONS: In this study, the antimalarial drug sulfadoxine induced gametocytogenesis in P. berghei, which could raise the risk factor for malaria transmission.


Assuntos
Antimaláricos , Plasmodium berghei , Sulfadoxina , Plasmodium berghei/efeitos dos fármacos , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Animais , Sulfadoxina/farmacologia , Sulfadoxina/uso terapêutico , Camundongos , Resistência a Medicamentos/genética , Gametogênese/efeitos dos fármacos , Feminino , Malária/tratamento farmacológico , Malária/parasitologia
18.
Parasitol Res ; 123(9): 329, 2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39316149

RESUMO

Aggregation is a fundamental feature of parasite distribution in the host population, but the biological implications of the aggregation indices used to describe the relationships between the populations of parasites and hosts are not evident. It is speculated that the form of distribution in each case is predicated on the host's varying resistance to the infection, which is hard to control, making it difficult to adequately interpret the index values. This paper examines several cases from trout farms in Russian Karelia to explore the monogenean Gyrodactylus spp. infection in rainbow trout of varying ages. The genetic homogeneity of cage-reared fish and the direct life cycle of the helminths make the relationship between the species more lucid than in natural host-parasite systems. The results give no ground to speak of any specific patterns: as well as in the natural systems, the infection rates in trout vary widely, i.e., the helminth distribution has not become more uniform; the observed distributions in all cases are adequately approximated by the negative binomial model; the positive abundance-occupancy relationships (AORs) and abundance-variance relationships (AVRs) common for parasitic systems apply to the basic infection parameters. The form of the negative binomial distribution is shaped by two parameters-k and θ, the former being a metric of the infection variability, which depends on the host's individual resistance, and the latter representing the parasites' reproduction and establishment success rates. A rise in the parameter k indicates increased aggregation and a higher parameter θ points to a more uniform frequency distribution. These parameters can be used as a representative tool for monitoring the parasite communities in salmonid fishes, including in aquaculture.


Assuntos
Doenças dos Peixes , Interações Hospedeiro-Parasita , Oncorhynchus mykiss , Trematódeos , Infecções por Trematódeos , Animais , Oncorhynchus mykiss/parasitologia , Doenças dos Peixes/parasitologia , Infecções por Trematódeos/veterinária , Infecções por Trematódeos/parasitologia , Trematódeos/fisiologia , Trematódeos/genética , Trematódeos/classificação , Trematódeos/isolamento & purificação , Federação Russa , Platelmintos/fisiologia , Platelmintos/genética , Platelmintos/classificação
19.
Open Biol ; 14(9): 240141, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39317333

RESUMO

Gregarines are a large and diverse subgroup of Apicomplexa, a lineage of obligate animal symbionts including pathogens such as Plasmodium, the malaria parasite. Unlike Plasmodium, however, gregarines are poorly studied, despite the fact that as early-branching apicomplexans they are crucial to our understanding of the origin and evolution of all apicomplexans and their parasitic lifestyle. Exemplifying this, the earliest branch of gregarines, the archigregarines, are particularly poorly studied: around 80 species have been described from marine invertebrates, but almost all of them were assigned to a single genus, Selenidium. Most are known only from light micrographs and largely unresolved rDNA phylogenies, where they exhibit a great deal of sequence variation, and fall into four subclades. To resolve the relationships within archigregarines, we sequenced 12 single-cell transcriptomes from species representing all four known subclades, as well as one blastogregarine (which frequently branch with Selenidium). A 190-gene phylogenomic tree confirmed four maximally supported individual clades of archigregarines and blastogregarines. These clades are discrete and distantly related, and also correlate with host identity. We propose the establishment of three novel genera of archigregarines to reflect their phylogenetic diversity and host range, and nine novel species isolated from a range of marine invertebrates.


Assuntos
Apicomplexa , Filogenia , Apicomplexa/genética , Apicomplexa/classificação , Animais , Transcriptoma , Variação Genética
20.
Trop Med Infect Dis ; 9(9)2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-39330884

RESUMO

The United States of America (US) has the highest annual number of human babesiosis cases caused by Babesia microti (Bm). Babesia, like malaria-causing Plasmodium, are protozoan parasites that live within red blood cells (RBCs). Both infectious diseases can be associated with hemolysis and organ damage, which can be fatal. Since babesiosis was made a nationally notifiable condition by the Centers for Disease Control and Prevention (CDC) in January 2011, human cases have increased, and drug-resistant strains have been identified. Both the Bm ligand(s) and RBC receptor(s) needed for invasion are unknown, partly because of the difficulty of developing a continuous in vitro culture system. Invasion pathways are relevant for therapies (e.g., RBC exchange) and vaccines. We hypothesize that there is at least one RBC surface antigen that is essential for Bm invasion and that all Bm hosts express this. Because most RBC surface antigens that impact Plasmodium invasion are in human blood group (hBG) systems, which are generated by 51 genes, they were the focus of this study. More than 600 animals with at least one hBG system gene ortholog were identified using the National Center for Biotechnology Information (NCBI) command-line tools. Google Scholar searches were performed to determine which of these animals are susceptible to Bm infection. The literature review revealed 28 Bm non-human hosts (NHH). For 5/51 (9.8%) hBG system genes (e.g., RhD), no NHH had orthologs. This means that RhD is unlikely to be an essential receptor for invasion. For 24/51 (47.1%) hBG system genes, NHH had 4-27 orthologs. For the ABO gene, 15/28 NHH had an ortholog, meaning that this gene is also unlikely to generate an RBC antigen, which is essential for Bm invasion. Our prior research showed that persons with blood type A, B, AB, O, RhD+, and RhD- can all be infected with Bm, supporting our current study's predictions. For 22/51 (43.1%) hBG system genes, orthologs were found in all 28 NHH. Nineteen (37.3%) of these genes encode RBC surface proteins, meaning they are good candidates for generating a receptor needed for Bm invasion. In vitro cultures of Bm, experimental Bm infection of transgenic mice (e.g., a CD44 KO strain), and analyses of Bm patients can reveal further clues as to which RBC antigens may be essential for invasion.

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