Acta Parasitologica

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Diagnosis of bovine neosporosis: Recent advances and perspectives
Acta Parasitologica - Tập 51 - Trang 1-14 - 2006
Luis M. Ortega-Mora, Aurora Fernández-García, Mercedes Gómez-Bautista
Neospora caninum is considered a major cause of abortion in cattle. Appropriate techniques for diagnosis of bovine neosporosis, both in vivo and in aborted foetuses, have been developed in the last ten years and some of them are commercially available. For diagnosis in live animals, detection of antibodies in serum or milk has been shown to be the best option both at the herd and the individual level. These techniques are excellent tools to examine N. caninum-associated abortion problems and to adopt some basic herd-control measures. Concerning foetal diagnosis, detection of compatible lesions by histological examination and parasites by PCR in brain (as well as heart and liver) are the best choices. Diagnostic criteria to distinguish foetal infection and Neospora-associated abortion are based not only on the demonstration of the parasite in the foetus but also on the extent and severity of the lesions in the foetus, foetal age and the assessment of neosporosis at the herd level. In the near future, new tools to diagnose infection should help to detect animals with parasite reactivation by testing the immune response to stage-specific antigens and lead to the development of molecular typing methods to characterise different parasite isolates. Finally, uniform diagnostic procedures need to be established between laboratories and countries in order to standardise result interpretation. The role of National or Regional Reference Laboratories is essential in countries or regions where control programmes for the disease are being developed.
In vitro observation of the stage conversion of transgenic Toxoplasma gondii RH strain expressing dual fluorescent proteins
Acta Parasitologica - Tập 61 - Trang 456-460 - 2016
Qijun Song, Ximeng Sun, Yongsheng Ji, Xinlei Yan, Jun Zou, Shiyun Zhao, Xun Suo, Xingquan Zhu, Xianyong Liu
Toxoplasma gondii converts from tachyzoites to bradyzoites after acute infection and thus survives the attack of the host immune responses. In this study, we observed the conversion of tachyzoites to bradyzoites in cell cultures using a transgenic T. gondii RH strain. The transgenic parasites continuously express yellow fluorescent protein (YFP) but only express red fluorescent protein (RFP) at the bradyzoite stage. Red fluorescent bradyzoite-containing cysts were found in transgenic parasite infected cells cultured with atmospheric CO2 supply, indicating the successful induction of the stage conversion. In cell culture with alkalic medium (pH 8.1) and atmospheric CO2 supply, only part of the YFP-expressing parasites in a cyst express RFP marker, suggesting the asynchronous development of T. gondii in vitro. This study provides a possibility for further studies of the gene expression profile during stage conversion and the genes involved.
Colonization of Rabbit Carcasses by Drain Fly Larvae, Psychoda sp. (Diptera: Psychodidae): The First Report
Acta Parasitologica - Tập 66 - Trang 706-709 - 2021
Nurul Azmiera, Van Lun Low, Chong Chin Heo
Psychoda sp. is often collected from patchy habitats such as sewers, drains and decomposing organic matters. The discovery of Psychoda sp. in forensic studies indicated that it might have noteworthy value in assisting death investigations. This study reports on the first finding of Psychoda larvae collected from decomposing rabbit carcasses placed in Cameron Highlands, Pahang, Malaysia. The larvae were first observed on rabbit carcasses and were collected using tweezers and carefully preserved in 70% ethanol. They were subsequently mounted on microscopy slides using Hoyer’s medium and identified as Psychoda sp. morphologically. The identification was also confirmed through a DNA barcoding analysis. Psychoda sp. larvae were collected on day-10 post-mortem where the rabbit carcasses were at the advanced decay stage of decomposition. The cytochrome c oxidase I (COI) gene sequences of the larvae had 90% similarity with the Psychoda spp. in the database. The finding of these larvae on carrion may provide additional valuable insights into forensic entomology and may assist in death investigations.
Phylogenetic Affinities and Infection Patterns of Goussia Infecting Sardina pilchardus from the NE Atlantic
Acta Parasitologica - Tập 66 - Trang 693-698 - 2021
Raquel Xavier, Ricardo Barroso, João Cardoso, Cristina Cruz, Ana Pereira, Aurélia Saraiva
European pilchard (Sardina pilchardus) is a highly valued fish in many European countries, particularly in Portugal. Despite current stock declines and the threats coccidia pose to European pilchards (e.g. castration), little is known about coccidian parasites infecting pilchards captured off the Portuguese coast. In this study, we analyzed the infection patterns, the morphology of oocysts and the phylogenetic relations of coccidian parasites from European pilchard captured in Northern Portugal. Only Goussia oocysts were detected in infected tissues and prevalence of infection was 64% (n = 61). Oocysts were detected primarily in the liver with fewer infections in the stomach, intestine and gonads. No differences were found in the prevalence between seasons. Phylogenetic analysis showed these parasites are closely related to Goussia clupearum, placing them within a recently described group of Goussia, the clupearum type. Our study provides more data on Goussia from the clupearum type with phylogenetic analysis indicating that these parasites cluster according to fish host taxonomy, thus suggesting some degree of co-evolution.
Prevalence of Giardia spp. in young dogs using a combination of two diagnostic methods
Acta Parasitologica - Tập 61 Số 2 - 2016
J. C. Alves, Ana Rita Ruas dos Santos
Abstract

In this study, prevalence of the protozoan parasites from the genus

Systematic revision of the feather mite genera Apexolichus Gaud et Atyeo and Titanolichus Gaud et Atyeo (Astigmata, Pterolichidae), parasites of parrots of the Old World (Psittaciformes, Psittacidae)
Acta Parasitologica - Tập 53 - Trang 46-80 - 2008
Jacek Dabert, Serge V. Mironov, Rainer Ehrnsberger
We present a systematic revision and phylogenetic analysis of feather mites of the closely related genera Apexolichus Gaud et Atyeo, 1996 and Titanolichus Gaud et Atyeo, 1996 (Pterolichidae, Pterolichinae). New diagnoses for Apexolichus and Titanolichus and keys to all known species are provided. We redescribe all species of the genus Protolichus Mégnin et Trouessart, 1884, described by E. Trouessart over a century ago, and which have been transferred to these genera. Two new species are described: Apexolichus psephoti sp. nov. from Psephotus varius Clark A.H., 1910 (type host) and P. haematonotus (Gould, 1838); and Titanolichus triangulifer sp. nov. from Barnardius zonaris (Shaw, 1805) (type host) and Northiella haematogaster (Gould, 1838). New synonymies are proposed: Apexolichus splendens (Favette et Trouessart, 1904) syn. nov. is a junior synonym of A. velifer (Trouessart, 1899); A. distensis (Favette et Trouessart, 1904) syn. nov. is a junior synonym of A. affinis (Mégnin et Trouessart, 1884). Apexolichus platycerci (Mironov, Dabert et Proctor, 2003) comb. nov. is a new combination for this species, which was formerly placed in the genus Titanolichus. Phylogenetic analysis (MP) confirms the monophyly of the genera Apexolichus and Titanolichus. Both of these genera, together with the monotypic genus Sideroferus Gaud et Atyeo, 1996 (being a sister group of Titanolichus), form a clade within the Protolichus generic group and are restricted in their host associations to parrots of the tribe Platycercini (Psittacidae, Psittacinae), members of which occur in the Australia and Indo-Malayan region. Representatives of each genus are restricted to a particular genus or a few genera of Platycercini. Host associations of these genera are briefly discussed.
Anti-Tumor Effect of Protoscolex Hydatid Cyst Somatic Antigen on Inhibition Cell Growth of K562
Acta Parasitologica - Tập 68 - Trang 385-392 - 2023
Atefe Asouli, Soheil Sadr, Hadi Mohebalian, Hassan Borji
Today, cancer is one of the most important causes of death in the world, and so far, many treatment methods have been used in this field. Immunotherapy is considered one of the newest developments in this science, and it is still being investigated in some forms in different cancers and with a variety of antigens as well. One of the subsets of cancer immunotherapy is its treatment using parasitic antigens. The present study evaluated the effect of using somatic antigens of protoscoleces of Echinococcus granulosus on K562 cancer cells. In this study, hydatid cysts’ protoscolex antigens were extracted, purified, and added to K562 cancer cells at three concentrations (0.1, 1, and 2 mg/ml) and on three times (24, 48, and 72 h). The number of apoptotic cells was compared to the control flask. The antigen concentration of 2 mg/ml was used as a control sample to investigate its cytotoxic effect on the growth of healthy HFF3 cells. Annexin V and PI tests were also performed to differentiate apoptosis from necrosis. In flasks treated with hydatid cyst protoscolex antigen, all three concentrations significantly reduced the growth of cancer cells compared with the control flask, and concentration 2 of crude antigen significantly caused the death of cancer cells. Furthermore, more cancer cells underwent apoptosis by increasing the time of exposure to the antigen. On the other hand, flow cytometry results also showed that the amount of apoptosis has increased compared to the control group. In fact, Protoscolex hydatid cyst somatic antigens induce programmed cell death in K562 cancer cells while not having a cytotoxic effect on normal cells. Therefore, it is suggested to do more research on the anti-cancer and therapeutic properties of the antigens of this parasite.
Parasitism of ectoparasitic flies on bats in the northern Brazilian cerrado
Acta Parasitologica - Tập 58 - Trang 207-214 - 2013
Ciro Líbio Caldas dos Santos, Agostinho Cardoso Nascimento Pereira, Vagner de Jesus Carneiro Bastos, Gustavo Graciolli, José Manuel Macário Rebêlo
In this work we record the highest number of bat flies species among those already performed in the Brazilian cerrado and discuss the associations and patterns of parasitism of these species and their hosts. A total of 1,390 ectoparasitic flies were collected, belonging to 24 species of Streblidae and one of Nycteribiidae, parasitizing 227 bats of 15 species. Among the species found, the presence of Trichobius sp. on Lonchophylla mordax and the first occurrence of Hershkovitzia sp. on Thyroptera devivoi are highlighted. Lophostoma species presented the highest proportion of individuals with infracommunities and the highest values of parasitological indexes. The high number of bat fly species and hosts, as well as the high values for rates of parasitism and infracommunities, suggests that this area of cerrado has good shelter conditions for these species. The abundance of species and high rates of parasitism detracts from the hypothesis that a higher mean intensity of ectoparasites results from lower competition among flies for hosts in areas with lower ectoparasite species richness. Biogeographical and historical factors of host populations, besides the number of host species and individuals sampled, may contribute to species number and intensity of parasitism.
Fasciola Infection Unexpectedly Found During Cholecystectomy: Review on How to Avoid Increasing Surgery Interventions in Non-human Endemic Areas
Acta Parasitologica - Tập 68 - Trang 891-902 - 2023
Gholamreza Mowlavi, María Dolores Bargues, Faezeh Najafi, Saied Reza Naddaf, Alireza Salehabadi, Amir Kazem Vejdan, Mahboobeh Salimi, Arezoo Fadavi, Zahra Arab-Mazar, Santiago Mas-Coma
Fascioliasis is caused by Fasciola hepatica of almost worldwide distribution and F. gigantica in wide regions of Asia and Africa. Their adult stage develops in the biliary canals and gallbladder. Infection follows an initial, 3–4 month long invasive, migratory or acute phase, and a several year-long biliary, chronic or obstructive phase. The unexpected finding of a fasciolid inside the gallbladder during a cholecystectomy for obstructive lithiasis suspicion in a patient is reported from an area of Iran where human infection had been never reported before and studies on fascioliasis in livestock are absent. The fluke obtained was phenotypically classified as F. hepatica by morphometry and genotypically as F. gigantica by mtDNA cox1 fragment sequencing, although with F. hepatica scattered mutations in species-differing nucleotide positions. The clinical, radiological, and biological signs observed at the acute and chronic phases often lead to some misdiagnosis. Serological methods may be useful in cases of negative coprology. Diagnostic techniques with insufficient resolution leading to unnecessary invasive interventions are analyzed. The way to avoid unnecessary surgery is described, including analyses to be made, diagnostic tools to be used, and aspects to be considered. Reaching a correct diagnosis in the confusing presentations avoids procedure delays and unnecessary surgery. A correct drug treatment may be sufficient. Except in extreme pathological presentations, lesions decrease in number and size and finally disappear or calcify after a successful treatment. Finally, the need to increase awareness of physicians about fascioliasis is highlighted, mainly in non-human endemic areas.
The First Report for the Presence of Spiroplasma and Rickettsia in Red Palm Weevil Rhynchophorus ferrugineus (Coleoptera: Curculionidae) in Egypt
Acta Parasitologica - Tập 66 - Trang 593-604 - 2021
Mona Awad, Abdoallah Sharaf, Tahany Abd Elrahman, Hassan Mohamed El-Saadany, Omnia Abdullah ElKraly, Sherif M. Elnagdy
The study of the Red Palm Weevil (RPW), Rhynchophorus ferrugineus (Olivier), as an invasive pest of palm trees. In this study, 36 RPW individuals were collected from 6 different locations in Egypt. The presences of endosymbionts in the RPW individuals were assayed. The phylogenetic analysis of the RPW inhabiting Egypt was conducted using Cytochrome c oxidase sub-unit 1 (CO1) gene. Spiroplasma was found, for the first time, in all individuals, while Rickettsia was found, for the first time, in individuals collected from only 3 of the 6 locations. Endosymbionts harbouring Egyptian RPW were closely related to those harbouring Diptera and\or Trombidiformes associated with palm trees. This may be due to horizontal transmission through palm sap or through ectoparasites living on the RPW. Finally, the phylogenetic analysis of the RPW inhabiting Egypt was conducted. The collected individuals were closely related to Saudi Arabia specimens collected from the eastern region. Thus, Saudi Arabia may be the origin of the RPW which invaded Egypt. Individuals from populations inhabiting the same geographical locations were closely related. This may be due to secondary invasion incidents that may have taken place through transportation of infested date palm trees and offshoots from infected to uninfected locations. This study reports the first incidence for the presence and coexistence of Spiroplasma and Rickettsia in RPW collected from Egypt. In addition, it was found that the collected individuals of RPW were closely related to a Saudi haplotype. Thus, Saudi Arabia may be the origin of infection which invaded Egypt.
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