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1.
Acta Trop ; 225: 106200, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34740636

RESUMO

Schistosomiasis, caused by a parasite with a wide range of mammalian hosts, remains one of the most prevailing parasitic diseases in the world. While numerous studies have reported that the growth and reproduction of schistosomes in immunodeficient mice was significantly retarded, the underlying molecular mechanisms have yet to be revealed. In this study, we comparatively analyzed the microRNA expression of Schistosoma japonicum derived from SCID and BALB/c mice on the 35th day post-infection by high-throughput RNA sequencing as prominent morphological abnormalities had been observed in schistosomes from SCID mice when compared with those from BALB/c mice. The results revealed that more than 72% and 61% of clean reads in the small RNA libraries of female and male schistosomes, respectively, could be mapped to the selected miRs in the miRBase or the sequences of species-specific genomes. Further analysis identified 122 miRNAs using TPM >0.01 as the threshold value, including 75 known and 47 novel miRNAs, 96 of which were commonly expressed across all the four tested schistosome libraries. Comparative analysis of the libraries of schistosomes from SCID and BALB/c mice identified 15 differentially expressed miRNAs (5 up-regulated and 10 down-regulated) among females and 16 among males (9 up-regulated and 7 down-regulated). Integrated analysis of the two sets of differentially expressed miRNAs of female and male worms identified 2 miRNAs (sja-miR-3488 and sja-miR-novel_29) that overlapped between female and male datasets. Prediction of miRNA targets and Gene Ontology (GO) term enrichment analysis of the predicted target genes revealed that these genes were involved in some important biological processes, such as nucleic acid metabolic process, macromolecule modification, and cellular aromatic compound metabolic process. The predicted target genes were further matched to the differentially expressed genes in male and female schistosomes from the above two hosts, obtaining 7 genes that may be responsible for regulating the growth, development and sex maturation of schistosomes. Taken together, this study provides the first identification of differentially expressed miRNAs in schistosomes from SCID and BALB/c mice. These miRNAs and their predicted target mRNAs are probably involved in the regulation of development, growth, and maturation of schistosomes. Therefore, this study expands our understanding of schistosome development regulation and host-parasite relationship, and also provides a valuable set of potential anti-schistosomal targets for prevention and control of schistosomiasis.


Assuntos
MicroRNAs , Parasitos , Schistosoma japonicum , Esquistossomose Japônica , Animais , Feminino , Crescimento e Desenvolvimento , Interações Hospedeiro-Parasita , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos SCID , MicroRNAs/genética , Schistosoma japonicum/genética
2.
Acta Trop ; 225: 106221, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34757042

RESUMO

We analyzed the peripheral blood lymphocyte subsets of cancer patients infected with intestinal parasites, with an aim to find out the relationship between the levels of different types of lymphocytes with the prognosis of patients. 201 cancer patients aged 18 and over were included. Stool samples of the patients were examined using native-lugol, trichrome, modified trichrome (Weber's Trichrome stain), and modified Ziehl-Neelsen staining methods. Microsporidia and Cryptosporidium parvum were investigated at the genus and species levels using PCR. Lymphocyte subsets were determined by flow cytometry in blood samples. One or more parasite species were detected in 115 (56.7%) patients. The most common parasite species were Microsporidia, Blastocystis and Entamoeba coli, respectively. The frequency of parasites was high in patients with low lymphocyte percentage, CD3+ T cell and CD3+ CD4+ T (Th) cell levels in blood samples studied by flow cytometry. Microsporidia infection was significantly higher in patients with low lymphocyte percentage and Th cell levels. Similarly, C. parvum infection was found to be significantly higher in patients with low T lymphocyte percentage and Th cell level. Finally, Blastocystis infection was significantly higher in patients with low lymphocyte percentage and CD4/CD8 ratio higher than 1. The decrease in lymphocyte percentage, CD3+ T cell and Th cell count, and low CD4/CD8 ratio in cancer patients increase the frequency of intestinal parasitic infections. Based on these results, lymphocyte subsets may help identify cancer patients at high risk of opportunistic parasites. We suggest that opportunistic parasitic infections affecting the clinical course of the disease should be considered by clinicians during the follow-up and treatment of patients.


Assuntos
Criptosporidiose , Cryptosporidium , Enteropatias Parasitárias , Parasitos , Adolescente , Adulto , Animais , Fezes , Humanos , Enteropatias Parasitárias/epidemiologia , Contagem de Linfócitos , Subpopulações de Linfócitos , Prevalência
3.
Acta Trop ; 225: 106182, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34627756

RESUMO

Leishmaniasis is a neglected tropical disease considered a public health problem that requires innovative strategies for its chemotherapeutic control. In the present investigation, a molecular docking approach was carried out using the protein cysteine synthase (CS) of Leishmania braziliensis (CSLb) and Leishmania major (CSLm) parasites to identify new compounds as potential candidates for the development of selective leishmaniasis therapy. CS protein sequence similarity, active site, structural modeling, molecular docking, and ADMET properties of compounds were analyzed using bioinformatics tools. Molecular docking analyses identified 1000 ligands with highly promising binding affinity scores for both CS proteins. A total of 182 compounds for CSLb and 173 for CSLm were selected for more detailed characterization based on the binding energy and frequency values and ADMET properties. Based on Principal Component Analysis (PCA) and K-means clusterization for both CS proteins, we classified compounds into 5 clusters for CSLb and 7 for CSLm, thus providing an excellent starting point for verification of enzyme inhibition in in vitro studies. We found the ZINC16524774 compound predicted to have a high affinity and stability for both CSLb and CSLm proteins, which was also evaluated through molecular dynamics simulations. Compounds within each of the five clusters also displayed pharmacological and structural properties that make them attractive drug candidates for the development of selective cutaneous leishmaniasis chemotherapy.


Assuntos
Leishmania braziliensis , Leishmania major , Parasitos , Animais , Cisteína , Cisteína Sintase , Simulação de Acoplamento Molecular
4.
Parasitol Int ; 86: 102486, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34710618

RESUMO

Various host characteristics (i. e., feeding habits, geographic distribution) and habitat characteristics (i.e., seasonality) influence the structure of parasite assemblages. To compare the parasite assemblages of hosts representatives of two genera of the same fish family, simultaneously occupying a geographic region, and to examine if seasonal variations influence parasite occurrence and abundance, we examined the parasite assemblages of two sympatric marine fish, Pagrus pagrus (n = 308) and Pagellus bogaraveo (n = 315) off the coast of Algeria in the western Mediterranean. Specimens were collected during summer and autumn over three consecutive years (2014-2016). Parasite assemblages were high in species richness and abundance. We compiled an inventory of 40 parasite taxa, including ectoparasitic monogeneans and crustaceans, and endoparasitic trematodes, cestodes, acanthocephalans, and nematodes. Endoparasite taxa primarily consisted of adult gastro-intestinal parasites and long lived larval helminths. Information on the parasite community structure and seasonal variations in parasite populations of these two hosts from the Mediterranean is here provided. Observed patterns of composition, diversity, dominance, and similarity indicate an overall consistency in assemblage structure. Although each host species harbored distinct parasite communities, they shared a high proportion of parasite species suggesting similar use of a common local pool of parasites. However, most shared species did not contribute to structuring the assemblages. Seasonal patterns in parasite abundance were observed for both hosts, with peak prevalence, abundance, and diversity in autumn. Results suggest that, regardless of a common pool of parasites being available to sympatric species, several ecological filters over time, led to distinct, independent variations in the parasite assemblages in each species.


Assuntos
Doenças dos Peixes/epidemiologia , Interações Hospedeiro-Parasita , Doenças Parasitárias em Animais/epidemiologia , Perciformes , Argélia/epidemiologia , Animais , Biodiversidade , Doenças dos Peixes/parasitologia , Mar Mediterrâneo/epidemiologia , Parasitos , Doenças Parasitárias em Animais/parasitologia , Estações do Ano , Especificidade da Espécie , Simpatria
5.
Wiad Lek ; 74(9 cz 1): 2232-2234, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34725307

RESUMO

Clonorchiasis is a parasitic disease caused by Clonorchis sinensis. Parasite colonies can develop not only in the bile and pancreatic ducts but also in the gastric wall. This is confirmed by the described clinical case of perforated gastric ulcer, the morphological study of which revealed parasite colonies in the wall of the organ.


Assuntos
Clonorquíase , Clonorchis sinensis , Parasitos , Animais , Bile , Clonorquíase/complicações , Clonorquíase/diagnóstico , Clonorquíase/tratamento farmacológico , Humanos
6.
J Helminthol ; 95: e64, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34753525

RESUMO

The round goby (Neogobius melanostomus) is a successful invader of the Great Lakes-St Lawrence River basin that harbours a number of local parasites. The most common are metacercariae of the genus Diplostomum. Species of Diplostomum are morphologically difficult to distinguish but can be separated using molecular techniques. While a few species have been sequenced from invasive round gobies in this study system, their relative abundance has not been documented. The purpose of this study was to determine the species composition of Diplostomum spp. and their relative abundance in round gobies in the St Lawrence River by sequencing the barcode region of cytochrome c oxidase I. In 2007-2011, Diplostomum huronense (=Diplostomum sp. 1) was the most common, followed in order by Diplostomum indistinctum (=Diplostomum sp. 4) and Diplostomum indistinctum sensu Galazzo, Dayanandan, Marcogliese & McLaughlin (2002). In 2012, the most common species infecting the round goby in the St Lawrence River was D. huronense, followed by D. indistinctum and Diplostomum gavium (=Diplostomum sp. 3). The invasion of the round goby in the St Lawrence River was followed by a decline of Diplostomum spp. in native fishes to low levels, leading to the previously published hypothesis that the presence of the round goby has led to a dilution effect. Herein, it is suggested that despite the low infection levels in the round goby, infections still may lead to spillback, helping to maintain Diplostomum spp. in native fishes, albeit at low levels.


Assuntos
Parasitos , Perciformes , Trematódeos , Animais , Peixes , Rios , Trematódeos/genética
7.
Dis Aquat Organ ; 147: 33-46, 2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34789586

RESUMO

The system formed by a still-unidentified rhizocephalan infecting the Patagonian stone crab Danielethus (Platyxanthus) patagonicus (A. Milne-Edwards, 1879) was analyzed in northern Patagonia. Out of 3222 crabs sampled, mean prevalence of externae was 2.1%, while corrected mean prevalence based on observations of externae, scars or other indicators of infection was slightly higher (3.01%; N = 2100). Prevalence was higher in males (4.47%) than in females (1.44%). Parasitized males were morphologically feminized, while females showed no hyper-feminization. Although most parasitized crabs showed only 1 externa, 2 externae were observed in some individuals. The parasite externae were only present in intermediate-sized crabs (26.6-99.7 cm carapace width). While scanning electron microscopy images allowed detection of the 'smooth-surface-balloon' type of retinacula on the inner surface of the externae, typical of the Sacculinidae and Peltogastridae, the position of the mantle opening relative to the stalk, the receptacle location and the shape of the externae suggest that the parasite belongs to either the genus Sacculina or to the recently erected Parasacculina (Polyascidae).


Assuntos
Braquiúros , Parasitos , Animais , Feminino , Interações Hospedeiro-Parasita , Masculino
8.
Toxicon ; 204: 37-43, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34756918

RESUMO

Adults of the ectoparasitic copepod Caligus fugu found on tetrodotoxin (TTX)-bearing pufferfish such as Takifugu alboplumbeus and Takifugu flavipterus are known to accumulate TTX in body tissues and parts other than the ovaries, oviducts, eggs, and cuticles. This study aimed to demonstrate, using immunoenzymatic staining techniques, that the TTX-free planktonic/infective copepodid stage of C. fugu could accumulate TTX in the tissues after molting into the parasitic stage (chalimus I) and then fed on mucus of host puffers. All the tissues of the planktonic copepodids were completely TTX-free, whereas chalimus I copepods accumulated TTX in parts other than the cuticles, guts, and some muscles. Chalimus IV and adult copepods retained TTX in these body parts but not in the reproductive organs, which were TTX-resistant, indicating that TTX was not vertically transmitted via eggs. Non-cellular TTX-positive contents found in the guts of some chalimi and adults indicated that the copepods potentially accumulated TTX by feeding on host mucus rather than skin tissues and blood. This study revealed that the presence or absence of TTX in some body parts differed among individuals of the parasite.


Assuntos
Copépodes , Parasitos , Animais , Feminino , Corpo Humano , Humanos , Muco , Takifugu , Tetrodotoxina
9.
Front Cell Infect Microbiol ; 11: 718028, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34737973

RESUMO

Host manipulation is a common strategy for invading pathogens. Trypanosoma cruzi, the causative agent of Chagas Disease, lives intracellularly within host cells. During infection, parasite-associated modifications occur to the host cell metabolism and morphology. However, little is known about the effect of T. cruzi infection on the host cell nucleus and nuclear functionality. Here, we show that T. cruzi can modulate host transcription and splicing machinery in non-professional phagocytic cells during infection. We found that T. cruzi regulates host RNA polymerase II (RNAPII) in a time-dependent manner, resulting in a drastic decrease in RNAPII activity. Furthermore, host cell ribonucleoproteins associated with mRNA transcription (hnRNPA1 and AB2) are downregulated concurrently. We reasoned that T. cruzi may hijack the host U2AF35 auxiliary factor, a key regulator for RNA processing, as a strategy to affect the splicing machinery activities directly. In support of our hypothesis, we carried out in vivo splicing assays using an adenovirus E1A pre-mRNA splicing reporter, showing that intracellular T. cruzi directly modulates the host cells by appropriating U2AF35. For the first time, our results provide evidence of a complex and intimate molecular relationship between T. cruzi and the host cell nucleus during infection.


Assuntos
Doença de Chagas , Parasitos , Trypanosoma cruzi , Animais , Núcleo Celular , Transcrição Genética , Trypanosoma cruzi/genética
10.
Front Cell Infect Microbiol ; 11: 751671, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34804994

RESUMO

Theileria parva is the causative agent of East Coast fever and Corridor disease, which are fatal, economically important diseases of cattle in eastern, central and southern Africa. Improved methods of control of the diseases are urgently required. The parasite transforms host lymphocytes, resulting in a rapid, clonal expansion of infected cells. Resistance to the disease has long been reported in cattle from T. parva-endemic areas. We reveal here that first- and second-generation descendants of a single Bos indicus bull survived severe challenge with T. parva, (overall survival rate 57.3% compared to 8.7% for unrelated animals) in a series of five field studies. Tolerant cattle displayed a delayed and less severe parasitosis and febrile response than unrelated animals. The in vitro proliferation of cells from surviving cattle was much reduced compared to those from animals that succumbed to infection. Additionally, some pro-inflammatory cytokines such as IL1ß, IL6, TNFα or TGFß which are usually strongly expressed in susceptible animals and are known to regulate cell growth or motility, remain low in tolerant animals. This correlates with the reduced proliferation and less severe clinical reactions observed in tolerant cattle. The results show for the first time that the inherited tolerance to T. parva is associated with decreased proliferation of infected lymphocytes. The results are discussed in terms of whether the reduced proliferation is the result of a perturbation of the transformation mechanism induced in infected cells or is due to an innate immune response present in the tolerant cattle.


Assuntos
Parasitos , Theileria parva , Theileriose , Animais , Bovinos , Proliferação de Células , Linfócitos , Masculino
11.
Braz J Biol ; 82: e242614, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34816974

RESUMO

Vegetables eating raw are a leading source of transmission of infective forms of pathogenic internal parasites among human beings. This research was conducted from April to October, 2017 to assess the parasitic contamination of vegetables sold at main vegetable markets in districts Lower Dir and Peshawar, Pakistan. Eight hundred specimens of different vegetables were purchased and soaked in physiological saline solution, shaken with a mechanical shaker for 20 minutes and processed by sedimentation concentration method. Results revealed that only 19.7% (n=158/800) of the vegetables were found to be contaminated with single or multiple parasite species. Ascaris lumbricoides (the large round worm) 12.3% (n=99/800) was the most commonly detected pathogen and Taenia saginata (the beef tapeworm) 1.62% (n=13/800) was the least frequently detected one. Interestingly, significant p value (p>0.05 at 95%CI) between the number of examined and contaminated for all the variables studied including education status of the vendors, markets location, type of vegetables, means of display, washed before display, washing source of water and market type. The findings of this study evidenced that consumption of raw vegetables possesses great risk of getting parasitic infections in Lower Dir and Peshawar districts, Pakistan. Instructing the sellers and the public about parasitic disease transfer and their hygiene can reduce the infection rate of parasites of human origin.


Assuntos
Nematoides , Parasitos , Animais , Bovinos , Contaminação de Alimentos/análise , Humanos , Saúde Pública , Verduras
12.
Front Cell Infect Microbiol ; 11: 769933, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34722348

RESUMO

Protozoans of the genus Leishmania are the causative agents of an important neglected tropical disease referred to as leishmaniasis. During their lifecycle, the parasites can colonize the alimentary tract of the sand fly vector and the parasitophorous vacuole of the mammalian host, differentiating into distinct stages. Motile promastigotes are found in the sand fly vector and are transmitted to the mammalian host during the insect blood meal. Once in the vertebrate host, the parasites differentiate into amastigotes and multiply inside macrophages. To successfully establish infection in mammalian hosts, Leishmania parasites exhibit various strategies to impair the microbicidal power of the host immune system. In this context, stage-specific class I nucleases play different and important roles related to parasite growth, survival and development. Promastigotes express 3'-nucleotidase/nuclease (3'-NT/NU), an ectoenzyme that can promote parasite escape from neutrophil extracellular traps (NET)-mediated death through extracellular DNA hydrolysis and increase Leishmania-macrophage interactions due to extracellular adenosine generation. Amastigotes express secreted nuclease activity during the course of human infection that may be involved in the purine salvage pathway and can mobilize extracellular nucleic acids available far from the parasite. Another nuclease expressed in amastigotes (P4/LmC1N) is located in the endoplasmic reticulum of the parasite and may be involved in mRNA stability and DNA repair. Homologs of this class I nuclease can induce protection against infection by eliciting a T helper 1-like immune response. These immunogenic properties render these nucleases good targets for the development of vaccines against leishmaniasis, mainly because amastigotes are the form responsible for the development and progression of the disease. The present review aims to present and discuss the roles played by different class I nucleases during the Leishmania lifecycle, especially regarding the establishment of mammalian host infection.


Assuntos
Armadilhas Extracelulares , Leishmania , Leishmaniose , Parasitos , Psychodidae , Animais , Humanos
13.
Front Cell Infect Microbiol ; 11: 774980, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34722349

RESUMO

Great progress has been made in the prevention and treatment of human parasitic diseases in China over the past six decades, but parasitic diseases are still one of the most serious public health problems in the world. The specific prevalence of parasitic diseases varies in different provinces due to their geographical environment and the dietary habits of people. In this study, a total of 4,428 patients suspected to have parasitic infection by clinicians or themselves from January 1, 2016, to December 31, 2020 were recommended to our laboratory for further testing. In total, 5,246 samples including fecal, blood, and other body fluids were detected by etiological and immunological methods. Approximately 15.20% (673/4,428) of all suspected patients were infected by at least one species of parasite, and the overall positive rate of suspected patients from Hunan Province was 15.10% (594/3,933). A total of 18 species of parasites, namely, nematodes (4 species), trematodes (5 species), cestodes (4 species), protozoa (2 species), and medical arthropods (3 species), and 3 of them were imported parasites outside of Hunan Province. There are 9 species of foodborne parasites, accounting for 89.92% (464/516) of patients infected by one species of parasite. Common parasites in Hunan Province include plerocercoid, Paragonimus westermani, Clonorchis sinensis, cysticercus, Toxoplasma gondii, and Schistosoma japonicum. In this study, we found that the incidence of soilborne nematode infections has decreased significantly. However, foodborne parasites gradually become the main parasitic infections as well as multiple infections are becoming more common. Therefore, we should not only continue the prevention and control of soil-derived nematodes but also focus on the prevention and control of foodborne parasites in the future.


Assuntos
Parasitos , Doenças Parasitárias , Animais , China/epidemiologia , Humanos , Doenças Parasitárias/epidemiologia , Prevalência , Solo
14.
Parasitol Res ; 120(12): 4067-4072, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34725733

RESUMO

Hepatozoon and Hemolivia are members of the haemogregarines and are reported in reptiles and reptile-associated ticks. However, no studies have reported on Hepatozoon and Hemolivia in Japanese reptile-associated ticks. This study aimed to molecularly identify and to characterize Hepatozoon and Hemolivia in Japanese reptile-associated ticks, Amblyomma geoemydae (Cantor, 1847) and Amblyomma nitidum (Hirst & Hirst, 1910). A total of 41 and 75 DNA samples from A. geoemydae and A. nitidum ticks, respectively, were used for screening of Hepatozoon and Hemolivia with polymerase chain reaction targeting 18S rDNA. As a result, Hemolivia and Hepatozoon were detected in two A. geoemydae and one A. nitidum, respectively. The sequences of Hemolivia spp. showed a 99.5% (1,050/1,055 bp) identity with Hemolivia parvula (KR069083), and the Hemolivia spp. were located in the same clade as H. parvula in the phylogenetic tree. The sequences of Hepatozoon sp. showed a 98.4% (1,521/1,545 bp) identity with Hepatozoon colubri (MN723844), and the Hepatozoon sp. was distinct from validated Hepatozoon species in the tree. Our findings highlight the first molecular record of Hemolivia in Japan and present the first detection of Hepatozoon in A. nitidum. Further investigations on these tick-borne protozoa are required to understand their life cycle and pathogenicity.


Assuntos
Parasitos , Carrapatos , Animais , Japão , Filogenia , RNA Ribossômico 18S/genética , Répteis
15.
Am Nat ; 198(6): 661-677, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34762573

RESUMO

AbstractInfection intensity can dictate disease outcomes but is typically ignored when modeling infection dynamics of microparasites (e.g., bacteria, virus, and fungi). However, for a number of pathogens of wildlife typically categorized as microparasites, accounting for infection intensity and within-host infection processes is critical for predicting population-level responses to pathogen invasion. Here, we develop a modeling framework we refer to as reduced-dimension host-parasite integral projection models (reduced IPMs) that we use to explore how within-host infection processes affect the dynamics of pathogen invasion and virulence evolution. We find that individual-level heterogeneity in pathogen load-a nearly ubiquitous characteristic of host-parasite interactions that is rarely considered in models of microparasites-generally reduces pathogen invasion probability and dampens virulence-transmission trade-offs in host-parasite systems. The latter effect likely contributes to widely predicted virulence-transmission trade-offs being difficult to observe empirically. Moreover, our analyses show that intensity-dependent host mortality does not always induce a virulence-transmission trade-off, and systems with steeper than linear relationships between pathogen intensity and host mortality rate are significantly more likely to exhibit these trade-offs. Overall, reduced IPMs provide a useful framework to expand our theoretical and data-driven understanding of how within-host processes affect population-level disease dynamics.


Assuntos
Interações Hospedeiro-Patógeno , Parasitos , Animais , Interações Hospedeiro-Parasita , Dinâmica Populacional , Virulência
16.
Zootaxa ; 4996(2): 363-373, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34810524

RESUMO

A new bopyrid, Pseudione chiesai n. sp., is herein described based on an ovigerous female and an adult male found in the right branchial chamber on a specimen of Munida spinosa Henderson, 1885. This parasite was collected in the Mar del Plata submarine canyon at 819 m depth during the expedition Talud Continental I carried out by the Argentine RV Puerto Deseado in 2012. P. chiesai n. sp. belongs to the Pseudione crels group sensu Bourdon (1972, 1976), which currently contains seven species, all of which have galatheoid crabs as hosts. P. chiesai n. sp. can be separated from the other species in the Pseudione crels group by the following combination of characters: (1) both sides of the body convex, (2) frontal lamina with a few, shallow indentations, (3) coxal plates 14 and tergal projections 14 with distinct irregular margins, mainly on the right side, (4) pereomeres 57 with single/branched lateral digitations, (5) maxilliped palp well-developed and setose, and (6) pleon with lateral plates 15 distally rounded and directed laterally. The taxonomic position of this new species is briefly discussed.


Assuntos
Anomuros , Braquiúros , Decápodes , Isópodes , Parasitos , Animais , Feminino , Masculino
17.
Zootaxa ; 5048(1): 99-117, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34810814

RESUMO

Previous work, using morphological characters, identified a generalist copepod parasite (Pharodes tortugensis) at high prevalence on two common gobies (Coryphopterus glaucofraenum and C. dicrus) in the British Virgin Islands (BVI). DNA barcoding subsequently revealed C. glaucofraenum to be three morphologically similar species (C. glaucofraenum, C. venezuelae and C. tortugae), casting doubt on host identities in the BVI and the classification of the parasite as a single species. Mitochondrial cytochrome c oxidase subunit I (COI) data from 67 gobies in the BVI showed that, in addition to C. dicrus, host gobies were a mix of C. glaucofraenum and C. venezuelae, while C. tortugae was unexpectedly absent from the study area. COI data (n = 70) indicated that the copepod infecting all three hosts was a single species, almost certainly P. tortugensis. The pharodes-coryphopterus interaction has a strong impact on host dynamics in the BVI, and a revised understanding of these dynamics must account for any differences among the three newly confirmed hosts in transmission of, and susceptibility to, the shared parasite. No other infected hosts were discovered at our sites, but P. tortugensis is reportedly widespread and infects 12 additional host species elsewhere. Further DNA barcoding is thus needed to test whether P. tortugensis is truly a widespread generalist, or instead represents a group of more specialized cryptic species.


Assuntos
Copépodes , Parasitos , Perciformes , Animais , Copépodes/genética , Código de Barras de DNA Taxonômico , Interações Hospedeiro-Parasita , Perciformes/genética , Filogenia
18.
Zootaxa ; 5039(4): 571-583, 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34811061

RESUMO

The article presents a brief review on the fauna of the axiidean and gebiidean burrowing mud shrimps and their external parasites in the northeastern coast of the Black Sea, where only two rather common species, Gilvossius candidus (Olivi, 1792) and Upogebia pusilla (Petagna, 1792) (Gebiidea: Upogebiidae), were previously recorded. Necallianassa truncata (Giard Bonnier, 1890) is confirmed and Gilvossius tyrrhenus (Petagna, 1792) (Axiidea: Callianassidae) is firstly recorded for the shallow waters of the northeastern Black Sea, where it was previously probably confused with common and widely distributed Gilvossius candidus (Olivi, 1792). Color photographs of the four species, enhancing the recognition of those species in fields, are provided.


Assuntos
Decápodes , Parasitos , Animais , Mar Negro , Crustáceos
19.
Front Cell Infect Microbiol ; 11: 748738, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34722338

RESUMO

Macrophage-Leishmania interactions are central to parasite growth and disease outcome. Macrophages have developed various strategies to fight invaders, including oxidative burst. While some microorganisms seem to survive and even thrive in an oxidative environment, others are susceptible and get killed. To counter oxidative stress, macrophages switch the expressions of cytoprotective and detoxifying enzymes, which are downstream targets of the nuclear factor erythroid 2-related factor 2 (Nrf2), to enhance cell survival. We have explored the transcription of NRF2 and of its target genes and compared the effect of the parasite on their transcription in bone marrow-derived macrophages (BMdMs) from Leishmania-resistant and Leishmania-susceptible mice. While heme oxygenase 1 (HO-1) transcription is independent of the genetic background, the transcription of glutathione reductase (Gsr) and of cysteine/glutamate exchange transporter (Slc7a11), involved in glutathione accumulation, was differentially regulated in BMdMs from both mouse strains. We also show that, except for HO-1, known to favor the survival of the parasite, the transcription of the selected genes, including Gsr, CD36, and catalase (CAT), was actively repressed, if not at all time points at least at the later ones, by the parasite, especially in Balb/c BMdMs. Consistent with these results, we found that the silencing of NRF2 in this study increases the survival and multiplication of the parasite.


Assuntos
Leishmania , Parasitos , Animais , Antioxidantes , Leishmania/genética , Macrófagos , Camundongos , Camundongos Endogâmicos BALB C , Estresse Oxidativo
20.
Planta ; 255(1): 4, 2021 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-34841446

RESUMO

MAIN CONCLUSION: Metabolites in Rafflesia-infected and non-infected Tetrastigma were compared which may have applications in Rafflesia propagation. Benzylisoquinoline alkaloids, here reported for the first time in Vitaceae, were abundant in non-infected shoots and may be a form of defense. In Rafflesia-infected shoots, oxylipins, which mediate immune response, were elevated. Endemic to the forests of Southeast Asia, Rafflesia (Rafflesiaceae) is a genus of holoparasitic plants producing the largest flowers in the world, yet completely dependent on its host, the tropical grape vine, Tetrastigma. Rafflesia species are threatened with extinction, making them an iconic symbol of plant conservation. Thus far, propagation has proved challenging, greatly decreasing efficacy of conservation efforts. This study compared the metabolites in the shoots of Rafflesia-infected and non-infected Tetrastigma loheri to examine how Rafflesia infection affects host metabolomics and elucidate the Rafflesia infection process. Results from LC-MS-based untargeted metabolomics analysis showed benzylisoquinoline alkaloids were naturally more abundant in non-infected shoots and are here reported for the first time in the genus Tetrastigma, and in the grape family, Vitaceae. These metabolites have been implicated in plant defense mechanisms and may prevent a Rafflesia infection. In Rafflesia-infected shoots, oxygenated fatty acids, or oxylipins, and a flavonoid, previously shown involved in plant immune response, were significantly elevated. This study provides a preliminary assessment of metabolites that differ between Rafflesia-infected and non-infected Tetrastigma hosts and may have applications in Rafflesia propagation to meet conservation goals.


Assuntos
Magnoliopsida , Parasitos , Vitaceae , Animais , Flores , Reprodução
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