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1.
J Infect Dis ; 229(2): 558-566, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-37889572

RESUMO

Congenital toxoplasmosis in humans and in other mammalian species, such as small ruminants, is a well-known cause of abortion and fetal malformations. The calcium-dependent protein kinase 1 (CDPK1) inhibitor BKI-1748 has shown a promising safety profile for its use in humans and a good efficacy against Toxoplasma gondii infection in vitro and in mouse models. Ten doses of BKI-1748 given every other day orally in sheep at 15 mg/kg did not show systemic or pregnancy-related toxicity. In sheep experimentally infected at 90 days of pregnancy with 1000 TgShSp1 oocysts, the BKI-1748 treatment administered from 48 hours after infection led to complete protection against abortion and congenital infection. In addition, compared to infected/untreated sheep, treated sheep showed a drastically lower rectal temperature increase and none showed IgG seroconversion throughout the study. In conclusion, BKI-1748 treatment in pregnant sheep starting at 48 hours after infection was fully effective against congenital toxoplasmosis.


Assuntos
Aborto Espontâneo , Doenças Transmissíveis , Toxoplasma , Toxoplasmose Congênita , Toxoplasmose , Gravidez , Humanos , Feminino , Camundongos , Ovinos , Animais , Toxoplasmose Congênita/tratamento farmacológico , Toxoplasmose Congênita/prevenção & controle , Mamíferos
2.
Exp Parasitol ; 255: 108655, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37981259

RESUMO

In previous studies, the artemisinin derivatives artemisone, its pro-drug artemiside and the bumped-kinase inhibitor BKI-1748 were effective against T. gondii via different modes of action. This suggests that they may act synergistically resulting in improved efficacies in vitro and in vivo. To test this hypothesis, the compounds were applied alone and in combination to T. gondii infected human fibroblast host cells in order to determine their inhibition constants and effects on cellular ultrastructure. In addition, the efficacy of either single- or combined treatments were assessed in an acute TgShSp1-oocyst infection model based on CD1 outbred mice. Whereas the IC50 of the compounds in combination (42 nM) was close to the IC50 of BKI-1748 alone (46 nM) and half of the IC50 of artemisone alone (92 nM), the IC90 of the combination was half of the values found with the single compounds (138 nM vs. ca. 270 nM). Another indication for synergistic effects in vitro were distinct alterations of the cellular ultrastructure of tachyzoites observed in combination, but not with the single compounds. These promising results could not be reproduced in vivo. There was no decrease in number of T. gondii positive brains by either treatment. However, the levels of infection in these brains, i. e. the number of tachyzoites, was significantly decreased upon BKI-1748 treatment alone, and the combination with artemiside did not produce any further decrease. The treatment with artemiside alone had no significant effects. A vertical transmission model could not be established since artemiside strongly interfered with pregnancy and caused abortion. These results show that is difficult to extrapolate from promising in vitro results to the situation in vivo.


Assuntos
Antineoplásicos , Artemisininas , Toxoplasma , Toxoplasmose , Gravidez , Feminino , Camundongos , Humanos , Animais , Toxoplasmose/tratamento farmacológico , Artemisininas/farmacologia , Artemisininas/uso terapêutico , Transmissão Vertical de Doenças Infecciosas , Antineoplásicos/farmacologia
3.
BMC Anesthesiol ; 23(1): 398, 2023 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-38057754

RESUMO

BACKGROUND: Lung isolation is a technique used in a multitude of surgeries to ensure single-lung ventilation with collapse of the contralateral lung, as to achieve improved access and visualization of relevant anatomical structures. Despite being accepted and having favorable outcomes, bronchial blockers (BBs) are not to this day the main device of choice among anaesthesiologists. METHODS: In this retrospective and descriptive study, we analyzed the safety and efficacy of a BB in all types of thoracic surgeries in our centre between 2015 and 2022, excluding patients with massive hemoptysis or empyema, or who had undergone a prior pneumonectomy. RESULTS: One hundred and thirty-four patients were intervened due to lung cancer (67.9%), respiratory disease (23.9%), and non-respiratory disease (8.2%) undergoing lung surgeries (65.7%), pleural and mediastinal surgeries (29.9%), chest wall surgeries (3.0%) and other surgeries (1.5%). In most cases, lung collapse was considered excellent (63.9%) or good (33.1%) with only 4 cases (3.0%) of poor lung collapse. More than 90% of patients did not present intraoperative or immediate postoperative complications. No statistically significant differences were found between lung collapse and the demographic, clinical or BB-related variables (p > 0.05). However, we found a significatively higher proportion of excellent lung collapses in VATS surgeries and lateral decubitus positioning, as well as a significatively less proportion of poor lung collapses (p < 0.05). Moreover, there was a significantly higher proportion of excellent lung collapses when the BB was placed in the left bronchus (p < 0.05). CONCLUSIONS: With these results, in our experience BBs constitute an effective alternative, capable of achieving pulmonary collapse in all kinds of thoracic procedures with satisfactory safety rates due to their minimal complications.


Assuntos
Ventilação Monopulmonar , Atelectasia Pulmonar , Procedimentos Cirúrgicos Torácicos , Humanos , Ventilação Monopulmonar/métodos , Estudos Retrospectivos , Brônquios/cirurgia , Procedimentos Cirúrgicos Torácicos/métodos , Intubação Intratraqueal/métodos , Cirurgia Torácica Vídeoassistida/métodos
4.
Am J Forensic Med Pathol ; 44(4): 258-266, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37417473

RESUMO

ABSTRACT: In postmortem toxicology analysis, a variety of specimens consisting of fluids and tissues are often collected, each with an intrinsic value. Oral cavity fluid (OCF) is emerging as an alternative matrix in forensic toxicology for contributing to a diagnosis in postmortem cases; especially when blood is limited or not available. The aim of this study was to assess the analytical results obtained from OCF and compare them with blood, urine, and other traditional matrices collected from the same postmortem subjects. Of the 62 decedents studied (including 1 stillborn, 1 charred, and 3 decomposed subjects), 56 had quantifiable drugs and metabolites data in the OCF, blood, and urine. Notable findings were benzoylecgonine (24 cases), ethyl sulfate (23 cases), acetaminophen (21 cases), morphine (21 cases), naloxone (21 cases), gabapentin (20 cases), fentanyl (17 cases), and 6-acetylmorphine (15 cases), which were detected more frequently in OCF than in blood (heart, femoral, or body cavity) or urine. This study suggests that OCF is a suitable matrix for detecting and quantifying analytes in postmortem subjects compared with traditional matrices, particularly when other matrices are limited or difficult to collect because of body condition or putrefaction.


Assuntos
Morfina , Boca , Humanos , Autopsia , Mudanças Depois da Morte , Fentanila , Toxicologia Forense/métodos
5.
Proc Natl Acad Sci U S A ; 116(45): 22764-22773, 2019 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-31636194

RESUMO

Neospora caninum, a cyst-forming apicomplexan parasite, is a leading cause of neuromuscular diseases in dogs as well as fetal abortion in cattle worldwide. The importance of the domestic and sylvatic life cycles of Neospora, and the role of vertical transmission in the expansion and transmission of infection in cattle, is not sufficiently understood. To elucidate the population genomics of Neospora, we genotyped 50 isolates collected worldwide from a wide range of hosts using 19 linked and unlinked genetic markers. Phylogenetic analysis and genetic distance indices resolved a single genotype of N. caninum Whole-genome sequencing of 7 isolates from 2 different continents identified high linkage disequilibrium, significant structural variation, but only limited polymorphism genome-wide, with only 5,766 biallelic single nucleotide polymorphisms (SNPs) total. Greater than half of these SNPs (∼3,000) clustered into 6 distinct haploblocks and each block possessed limited allelic diversity (with only 4 to 6 haplotypes resolved at each cluster). Importantly, the alleles at each haploblock had independently segregated across the strains sequenced, supporting a unisexual expansion model that is mosaic at 6 genomic blocks. Integrating seroprevalence data from African cattle, our data support a global selective sweep of a highly inbred livestock pathogen that originated within European dairy stock and expanded transcontinentally via unisexual mating and vertical transmission very recently, likely the result of human activities, including recurrent migration, domestication, and breed development of bovid and canid hosts within similar proximities.


Assuntos
Genoma , Interações Hospedeiro-Parasita , Neospora/genética , Animais , Bovinos , Genótipo , Recombinação Genética
6.
Int J Mol Sci ; 23(4)2022 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-35216497

RESUMO

Neospora caninum is an apicomplexan parasite closely related to Toxoplasma gondii, and causes abortions, stillbirths and/or fetal malformations in livestock. Target-based drug development has led to the synthesis of calcium-dependent protein kinase 1 inhibitors, collectively named bumped kinase inhibitors (BKIs). Previous studies have shown that several BKIs have excellent efficacy against neosporosis in vitro and in vivo. However, several members of this class of compounds impair fertility in pregnant mouse models and cause embryonic malformation in a zebrafish (Danio rerio) model. Similar to the first-generation antiprotozoal drug quinine, some BKIs have a quinoline core structure. To identify common targets in both organisms, we performed differential affinity chromatography with cell-free extracts from N. caninum tachyzoites and D. rerio embryos using the 5-aminopyrazole-4-carboxamide (AC) compound BKI-1748 and quinine columns coupled to epoxy-activated sepharose followed by mass spectrometry. BKI-binding proteins of interest were identified in eluates from columns coupled to BKI-1748, or in eluates from BKI-1748 as well as quinine columns. In N. caninum, 12 proteins were bound specifically to BKI-1748 alone, and 105 proteins, including NcCDPK1, were bound to both BKI-1748 and quinine. For D. rerio, the corresponding numbers were 13 and 98 binding proteins, respectively. In both organisms, a majority of BKI-1748 binding proteins was involved in RNA binding and modification, in particular, splicing. Moreover, both datasets contained proteins involved in DNA binding or modification and key steps of intermediate metabolism. These results suggest that BKI-1748 interacts with not only specific targets in apicomplexans, such as CDPK1, but also with targets in other eukaryotes, which are involved in common, essential pathways.


Assuntos
Neospora/metabolismo , Inibidores de Proteínas Quinases/metabolismo , Quinolonas/metabolismo , Peixe-Zebra/metabolismo , Animais , Antiprotozoários/metabolismo , Células Cultivadas , Quinolinas/metabolismo
7.
Vet Res ; 52(1): 82, 2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-34112256

RESUMO

Toxoplasma gondii is an important zoonotic agent with high genetic diversity, complex epidemiology, and variable clinical outcomes in animals and humans. In veterinary medicine, this apicomplexan parasite is considered one of the main infectious agents responsible for reproductive failure in small ruminants worldwide. The aim of this study was to phenotypically characterize 10 Spanish T. gondii isolates recently obtained from sheep in a normalized mouse model and in an ovine trophoblast cell line (AH-1) as infection target cells. The panel of isolates met selection criteria regarding such parameters as genetic diversity [types II (ToxoDB #1 and #3) and III (#2)], geographical location, and sample of origin (aborted foetal brain tissues or adult sheep myocardium). Evaluations of in vivo mortality, morbidity, parasite burden and histopathology were performed. Important variations between isolates were observed, although all isolates were classified as "nonvirulent" (< 30% cumulative mortality). The isolates TgShSp16 (#3) and TgShSp24 (#2) presented higher degrees of virulence. Significant differences were found in terms of in vitro invasion rates and tachyzoite yield at 72 h post-inoculation (hpi) between TgShSp1 and TgShSp24 isolates, which exhibited the lowest and highest rates, respectively. The study of the CS3, ROP18 and ROP5 loci allelic profiles revealed only type III alleles in ToxoDB #2 isolates and type II alleles in the #1 and #3 isolates included. We concluded that there are relevant intra- and inter-genotype virulence differences in Spanish T. gondii isolates, which could not be inferred by genetic characterization using currently described molecular markers.


Assuntos
Genótipo , Doenças dos Ovinos/parasitologia , Toxoplasma/patogenicidade , Toxoplasmose Animal/parasitologia , Animais , Camundongos , Ovinos , Carneiro Doméstico , Espanha , Toxoplasma/genética , Virulência/genética
8.
Vet Res ; 52(1): 106, 2021 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-34294155

RESUMO

Breeding bulls infected with Besnoitia besnoiti may develop sterility during either acute or chronic infection. The aim of this study was to investigate the molecular pathogenesis of B. besnoiti infection with prognosis value in bull sterility. Accordingly, five well-characterized groups of naturally and experimentally infected males were selected for the study based on clinical signs and lesions compatible with B. besnoiti infection, serological results and parasite detection. A broad panel of molecular markers representative of endothelial activation and fibrosis was investigated and complemented with a histopathological approach that included conventional histology and immunohistochemistry. The results indicated the predominance of an intense inflammatory infiltrate composed mainly of resident and recruited circulating macrophages and to a lesser extent of CD3+ cells in infected bulls. In addition, a few biomarkers were associated with acute, chronic or subclinical bovine besnoitiosis. The testicular parenchyma showed a higher number of differentially expressed genes in natural infections (acute and chronic infections) versus scrotal skin in experimental infections (subclinical infection). In subclinical infections, most genes were downregulated except for the CCL24 and CXCL2 genes, which were upregulated. In contrast, the acute phase was mainly characterized by the upregulation of IL-1α, IL-6 and TIMP1, whereas in the chronic phase, the upregulation of ICAM and the downregulation of MMP13, PLAT and IL-1α were the most relevant findings. Macrophages could be responsible for the highest level of gene regulation in the testicular parenchyma of severely affected and sterile bulls, and all these genes could be prognostic markers of sterility.


Assuntos
Doenças dos Bovinos/fisiopatologia , Coccidiose/veterinária , Progressão da Doença , Sarcocystidae/isolamento & purificação , Doenças Testiculares/veterinária , Testículo/fisiopatologia , Animais , Biomarcadores/análise , Bovinos , Coccidiose/fisiopatologia , Masculino , Doenças Testiculares/fisiopatologia
9.
Parasitol Res ; 120(8): 2995-3000, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34292375

RESUMO

Neospora caninum is a major reproductive disease in cattle worldwide. In the Argentinian Humid Pampa, the seroprevalence, incidence of abortions, and economic losses due to neosporosis are considerably higher in dairy than in beef cattle. Despite this, we recently demonstrated that N. caninum subpopulations are indistinctly distributed in both dairy and beef production systems. The association between genotypic characteristics defined by microsatellite analysis and the virulence of the different strains-particularly with regard to the severity and extension of histological lesions-is largely unknown. Herein, we used a morphometric approach to analyze encephalic lesions in 62 bovine fetuses spontaneously infected by N. caninum. Morphometric parameters (average size of focal lesions, number of foci/cm2 and the percentage of the section affected by lesions) were compared according to the N. caninum subpopulations found in our previous microsatellite genotyping analysis, animal biotype (beef versus dairy), and fetal age (second stage of gestation versus third stage). The average size of the lesions differed significantly among fetuses with different gestational ages; however, no significant differences among animal biotypes or genotypic patterns were found. Further research into the genetic, molecular, and husbandry factors that could account for this greater impact in Argentinian dairy herds is needed.


Assuntos
Aborto Animal , Doenças dos Bovinos , Coccidiose , Neospora , Animais , Anticorpos Antiprotozoários , Argentina , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/parasitologia , Coccidiose/veterinária , Feminino , Feto/parasitologia , Feto/patologia , Neospora/genética , Neospora/imunologia , Gravidez , Estudos Soroepidemiológicos
10.
Plant Dis ; 2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33754851

RESUMO

Peanut (Arachis hypogaea L.) is the third most important oilseed crop in the world. The cultivated area in Mexico is currently 52,046 ha with a production of 91,109 ton in 2018 (FAO, 2020). Puebla state ranks third in the national production with 9,313 ton (SIAP, 2020). In September 2019, typical symptoms of charcoal rot (Macrophomina phaseolina (Tassi) Goid.) were observed in about 50% of cultivar Virginia Champs peanuts, and it affecting 1.5 ha located in Chietla (18° 27' 39" N; 98° 37' 11" W), Puebla, Mexico. Diseased plants showed brown discoloration in stem and root rot, with chlorotic foliage, dark microsclerotia were observed on the stem and premature dying. To isolate the causal agent of these symptoms, 20 infected plants were recovered and processed in the laboratory. Ten pieces of stem and root tissue were selected from each plant, cut into small pieces 5-mm in length, superficially disinfested with 1% sodium hypochlorite for 3 min, followed by three rinses with sterile distilled water. Later, dried on sterile paper and placed on Petri plates containing potato dextrose agar (PDA) medium, which were kept at 28°C for 7 days (12 h light and 12 h dark). Four colonies were purified via hyphal tip culture, fungus was consistently isolated from the analyzed tissues; additional microcultures were prepared to observe phenotypic characteristics. Colonies showed dense growth, with a gray initial mycelium, becoming black after 7 days. Microesclerotia with spherical to oblong in shape were observed after 5 days on PDA, with a black coloration, measuring an average of 74 µm width × 110 µm length (n=40). Phylogenetic analysis was conducted by amplification and sequencing of the internal transcribed spacer (ITS) region with the ITS5 and ITS4 primers (White et al. 1990). The obtained sequences were deposited in GenBank database under accession numbers: MW585378, MW585379, MW585380, and MW585381 containing approximately 601 bp of the ITS1-5.8S-ITS2 region (complete sequence); they were 99% identical with the reference sequence of Macrophomina phaseolina (GenBank accession KF951698) isolated in Phaseolus vulgaris from Mexico. Based on the symptoms in the field, colony morphology, color, and shape of the microsclerotia, and molecular identification, the fungus was identified as M. phaseolina (Tassi) Goid. The pathogenicity test was performed on peanut plants cultivar Virginia Champs grown on plastic pots with an autoclaved peat/soil mixture under greenhouse conditions (70% relative humidity and 28°C). Fifty two-month-old peanut plants were inoculated using the toothpick method. The toothpicks were previously sterilized and then placed in Petri plates with each of the four colonies of M. phaseolina until colonization. Small wounds were made with those toothpicks in the roots, and a sterile toothpick was used in the control plants, the assays were performed twice. After three weeks, the inoculated plants exhibited symptoms of wilting chlorosis on the leaves and brown to dark brown discoloration of the vascular ring, while control plants remained healthy. M. phaseolina was re-isolated from symptomatic root tissues and identified by phylogenetic approach, fulfilling Koch's postulates. To date, this fungus affects at least 372 hosts globally causing yield losses. Although in Mexico this fungus has been documented in Glycine max, Ipomoea batatas, Phaseolus vulgaris, Physalis ixocarpa, Saccharum officinarum, Sesamum indicum, Solanum melongena, S. tuberosum, and Sorghum bicolor (Farr and Rossman 2021). However, there are no reports of M. phaseolina as a potential pathogen on peanut; therefore, according to our knowledge, this is the first report of this fungus affecting A. hypogaea in Mexico.

11.
Sensors (Basel) ; 22(1)2021 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-35009837

RESUMO

The synthetic cathinones mephedrone (4-MMC) and 4-methylethcathinone (4-MEC) are two designer drugs that represent the rise and fall effect of this drug category within the stimulants market and are still available in several countries around the world. As a result, the qualitative and quantitative determination of 'legal highs', and their mixtures, are of great interest. This work explores for the first time the spectroelectrochemical response of these substances by coupling cyclic voltammetry (CV) with Raman spectroscopy in a portable instrument. It was found that the stimulants exhibit a voltammetric response on a gold screen-printed electrode while the surface is simultaneously electro-activated to achieve a periodic surface-enhanced Raman spectroscopy (SERS) substrate with high reproducibility. The proposed method enables a rapid and reliable determination in which both substances can be selectively analyzed through the oxidation waves of the molecules and the characteristic bands of the electrochemical SERS (EC-SERS) spectra. The feasibility and applicability of the method were assessed in simulated seized drug samples and spiked synthetic urine. This time-resolved spectroelectrochemical technique provides a cost-effective and user-friendly tool for onsite screening of synthetic stimulants in matrices with low concentration analytes for forensic applications.


Assuntos
Ouro , Análise Espectral Raman , Eletrodos , Reprodutibilidade dos Testes
12.
Molecules ; 26(7)2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33917445

RESUMO

The purpose of the study was to develop a novel, directly compressible, co-processed excipient capable of providing a controlled-release drug system for the pharmaceutical industry. A co-processed powder was formed by adsorption of solid lipid nanoparticles (SLN) as a controlled-release film onto a functional excipient, in this case, dicalcium phosphate dihydrate (DPD), for direct compression (Di-Tab®). The co-processed excipient has advantages: easy to implement; solvent-free; industrial scaling-up; good rheological and compressibility properties; and the capability to form an inert platform. Six different batches of Di-Tab®:SLN weight ratios were prepared (4:0.6, 3:0.6, 2:0.6, 1:0.6, 0.5:0.6, and 0.25:0.6). BCS class III ranitidine hydrochloride was selected as a drug model to evaluate the mixture's controlled-release capabilities. The co-processed excipients were characterized in terms of powder rheology and dissolution rate. The best Di-Tab®:SLN ratio proved to be 2:0.6, as it showed high functionality with good flow and compressibility properties (Carr Index = 16 ± 1, Hausner Index = 1.19 ± 0.04). This ratio could control release for up to 8 h, so it fits the ideal profile calculated based on biopharmaceutical data. The compressed systems obtained using this powder mixture behave as a matrix platform in which Fickian diffusion governs the release. The Higuchi model can explain their behavior.


Assuntos
Preparações de Ação Retardada/farmacologia , Excipientes/química , Lipídeos/química , Nanopartículas/química , Força Compressiva , Liberação Controlada de Fármacos , Nanopartículas/ultraestrutura , Tamanho da Partícula , Pós , Ranitidina/farmacologia , Reologia
13.
Molecules ; 26(21)2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34770802

RESUMO

The quinolone decoquinate (DCQ) is widely used in veterinary practice for the treatment of bacterial and parasitic infections, most notably, coccidiosis in poultry and in ruminants. We have investigated the effects of treatment of Toxoplasma gondii in infected human foreskin fibroblasts (HFF) with DCQ. This induced distinct alterations in the parasite mitochondrion within 24 h, which persisted even after long-term (500 nM, 52 days) treatment, although there was no parasiticidal effect. Based on the low half-maximal effective concentration (IC50) of 1.1 nM and the high selectivity index of >5000, the efficacy of oral treatment of pregnant mice experimentally infected with T. gondii oocysts with DCQ at 10 mg/kg/day for 5 days was assessed. However, the treatment had detrimental effects, induced higher neonatal mortality than T. gondii infection alone, and did not prevent vertical transmission. Thus, three quinoline-O-carbamate derivatives of DCQ, anticipated to have better physicochemical properties than DCQ, were assessed in vitro. One such compound, RMB060, displayed an exceedingly low IC50 of 0.07 nM, when applied concomitantly with the infection of host cells and had no impact on HFF viability at 10 µM. As was the case for DCQ, RMB060 treatment resulted in the alteration of the mitochondrial matrix and loss of cristae, but the changes became apparent at just 6 h after the commencement of treatment. After 48 h, RMB060 induced the expression of the bradyzoite antigen BAG1, but TEM did not reveal any other features reminiscent of bradyzoites. The exposure of infected cultures to 300 nM RMB060 for 52 days did not result in the complete killing of all tachyzoites, although mitochondria remained ultrastructurally damaged and there was a slower proliferation rate. The treatment of mice infected with T. gondii oocysts with RMB060 did reduce parasite burden in non-pregnant mice and dams, but vertical transmission to pups could not be prevented.


Assuntos
Antiprotozoários/farmacologia , Carbamatos , Decoquinato/farmacologia , Quinolinas/farmacologia , Toxoplasma/efeitos dos fármacos , Toxoplasmose Animal/tratamento farmacológico , Toxoplasmose Animal/parasitologia , Animais , Antiprotozoários/química , Carbamatos/química , Decoquinato/análogos & derivados , Decoquinato/química , Modelos Animais de Doenças , Feminino , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Camundongos , Estrutura Molecular , Oocistos/efeitos dos fármacos , Gravidez , Quinolinas/química , Toxoplasma/ultraestrutura
14.
Vet Res ; 51(1): 83, 2020 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-32552750

RESUMO

Neospora caninum is an apicomplexan cyst-forming parasite that is considered one of the main causes of abortion. The pathogenic mechanisms associated with parasite virulence at the maternal-foetal interface that are responsible for the outcome of infection are largely unknown. Here, utilizing placentomes from cattle experimentally infected with high-virulence (Nc-Spain7) and low-virulence (Nc-Spain1H) isolates, we studied key elements of the innate and adaptive immune responses, as well as components of the extracellular matrix (ECM), at 10 and 20 days post-infection (dpi). The low-virulence isolate elicited a robust immune response characterized by upregulation of genes involved in pathogen recognition, chemokines and pro-inflammatory cytokines, crucial for its adequate control. In addition, Nc-Spain1H triggered the expression of anti-inflammatory cytokines and other mechanisms implicated in the maintenance of ECM integrity to ensure foetal survival. In contrast, local immune responses were initially (10 dpi) impaired by Nc-Spain7, allowing parasite multiplication. Subsequently (20 dpi), a predominantly pro-inflammatory Th1-based response and an increase in leucocyte infiltration were observed. Moreover, Nc-Spain7-infected placentomes from animals carrying non-viable foetuses exhibited higher expression of the IL-8, TNF-α, iNOS and SERP-1 genes and lower expression of the metalloproteases and their inhibitors than Nc-Spain7-infected placentomes from animals carrying viable foetuses. In addition, profound placental damage characterized by an alteration in the ECM organization in necrotic foci, which could contribute to foetal death, was found. Two different host-parasite interaction patterns were observed at the bovine placenta as representative examples of different evolutionary strategies used by this parasite for transmission to offspring.


Assuntos
Imunidade Adaptativa , Doenças dos Bovinos/imunologia , Coccidiose/veterinária , Matriz Extracelular/imunologia , Interações Hospedeiro-Parasita , Imunidade Inata , Neospora/fisiologia , Animais , Bovinos , Coccidiose/imunologia , Feminino , Placenta/imunologia , Gravidez
15.
Vet Pathol ; 57(4): 545-549, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32452287

RESUMO

Early abortion in ovine toxoplasmosis has had limited investigation. This study evaluated the immune response in the placenta of sheep orally infected with Toxoplasma gondii and euthanized between 2 and 4 weeks postinfection. Toxoplasma infection of the placenta was only found at 4 weeks after infection. Parasitic debris in foci of necrosis were immunolabeled in the maternal caruncle, whereas well-preserved intracellular parasitic vacuole-like structures were found in trophoblasts of fetal cotyledon. Early abortions had increased macrophages in caruncular septa, whereas in later abortions the placentas containing the parasite had an increase of T lymphocytes and macrophages mainly in the fetal cotyledons. This study suggests that the immune response in both the fetal and maternal compartments of the placenta may contribute to the pathogenesis of ovine toxoplasmosis and that these responses differ between early and late presentations of the disease.


Assuntos
Aborto Animal , Macrófagos/patologia , Doenças dos Ovinos/patologia , Linfócitos T/patologia , Toxoplasmose Animal , Aborto Animal/parasitologia , Aborto Animal/patologia , Animais , Feminino , Imunidade , Imuno-Histoquímica/veterinária , Necrose/parasitologia , Necrose/patologia , Placenta/imunologia , Placenta/patologia , Gravidez , Ovinos , Toxoplasma/isolamento & purificação , Toxoplasma/patogenicidade , Toxoplasmose Animal/imunologia , Toxoplasmose Animal/patologia
16.
Vet Pathol ; 57(4): 535-544, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32406321

RESUMO

There is an unacknowledged clinical presentation of ovine toxoplasmosis characterized by early abortions and lesions of fetal leukoencephalomalacia. To investigate the pathogenesis of this condition, the extent and distribution of leukomalacia and the variations in the cell populations associated with it were characterized in 32 fetal brains from 2 previously published experimental studies of Toxoplasma gondii infection in pregnant sheep. Immunohistochemical labeling of ßAPP allowed for the detection of leukomalacia in 100/110 (91%) studied samples. There was no clear influence of the challenge dose or the area of the brain (frontal lobe, corpus callosum, midbrain, and cerebellum). In tissues with leukomalacia, there was loss of oligodendrocytes and increased number of astrocytes and microglia both in the areas of necrosis but also in the surrounding area. These findings were similar to those described in ovine experimental models (inflammation syndrome and hypoxic models) of periventricular leukomalacia in humans. Thus, a fetal inflammatory syndrome may be involved in the pathogenesis of early abortion in ovine toxoplasmosis. However, further studies are needed to determine the pathogenesis of this clinical presentation because placental thrombosis and resulting hypoxia could also be responsible for the leukomalacia.


Assuntos
Aborto Animal/patologia , Encéfalo/patologia , Feto/patologia , Doenças dos Ovinos/patologia , Toxoplasmose Animal/patologia , Aborto Animal/parasitologia , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Astrócitos/patologia , Feminino , Imuno-Histoquímica/veterinária , Leucoencefalopatias/veterinária , Microglia/patologia , Necrose/patologia , Necrose/veterinária , Gravidez , Ovinos , Toxoplasma/patogenicidade
17.
Parasitol Res ; 119(4): 1353-1362, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32157394

RESUMO

Recent studies have revealed extensive genetic variations among Neospora caninum, a cyst-forming protozoan parasite that is one of the main causes of bovine abortion in the cattle industry worldwide. Previous genetic studies based on multilocus microsatellite genotyping (MLGs) of different Ibero-American populations showed a high genetic diversity. These studies provided clear clues of a predominant clonal propagation in cattle and population sub-structuring partially associated with geographical origin. Although, these reports were limited to a reduced number of countries. In this study, the N. caninum isolates from aborted bovine fetuses and stillbirths and a goat abortion from Northern Italy were investigated genetically using 9 microsatellite markers. Complete or nearly complete isolate profiles were obtained from 30 fetuses and stillbirths. An extensive genetic diversity was also found in this Italian N. caninum population. The study of genetic relationships among Italian MLGs using network (eBURST) and principal component analyses based on the allele-sharing coefficient (PCoA) showed different clonal subpopulations disseminated throughout Northern Italy without apparent segregation depending on the geographic origin, cattle breed, or time of collection. The presence of linkage disequilibrium supports a predominant clonal propagation of Italian N. caninum. In addition, most of Italian MLGs segregated from other global populations including Spain, Argentina, Mexico, Brazil, Germany, and Scotland, suggesting the existence of specific N. caninum subpopulations in the Northern Italy and different subpopulations of N. caninum circulating in Europe.


Assuntos
Aborto Animal/parasitologia , Doenças dos Bovinos/parasitologia , Coccidiose/veterinária , Neospora/genética , Feto Abortado/parasitologia , Animais , Bovinos , Feminino , Feto/parasitologia , Variação Genética/genética , Geografia , Cabras/genética , Itália , Desequilíbrio de Ligação/genética , Repetições de Microssatélites/genética , Neospora/classificação , Neospora/isolamento & purificação , Gravidez
18.
Parasitol Res ; 119(8): 2679-2686, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32588173

RESUMO

Rodents and other micromammals constitute important reservoirs of infectious diseases; their role in the life cycle of apicomplexan parasites such as Toxoplasma gondii, Neospora caninum, and Sarcocystis spp. still needs clarification. In the present study, we analyzed by PCR and Sanger sequencing methods the presence of specific parasite DNA within brain and heart tissues of 313 individuals of five synanthropic small mammal species (Apodemus sylvaticus, Mus spretus, M. musculus, Rattus rattus, and Crocidura russula) collected in Barcelona metropolitan area (NE Spain). In addition, PCR-RFLP and microsatellites were also used as tools for genotypic characterization of T. gondii and N. caninum, respectively. Specific DNA of T. gondii, N. caninum, and Sarcocystis spp. was detected in 0.3% (n = 1), 1.3% (n = 4), and 3.8% (n = 12) of the animals, respectively. No mixed infections were observed. Crocidura russula stood out as the main host for Sarcocystis spp. Toxoplasma gondii-specific DNA detected in a house rat was genetically characterized by PCR-RFLP, presenting type II and III alleles (SAG1 [II], SAG3 [II], GRA6 [II], c22-8 [III], Apico [III]). Also, unsuccessful DNA sequencing and microsatellite typing were attempted in N. caninum-positive samples, which suggested a lack of PCR specificity and open avenues to speculate the host competence of rodents for N. caninum. Likewise, Sarcocystis spp. identity was studied by alignment and phylogenetic analyses of cox1 and 28S rRNA sequences from the 14 positive samples. It resulted in at least three unknown organisms closely similar (95.7-100% cox1-sequence homology) to Sarcocystis pantherophisi from the Eastern rat snake (Pantherophis alleghaniensis) (KU891603), suggesting together with 28S rRNA sequences analyses, three Sarcocystis sp. with a life cycle conformed by rodents as intermediate host (IH) and snakes as definitive hosts (DH) infecting the periurban micromammals surveyed. Prevalence figures found in this first survey carried out in Spain agree with other international studies focused on periurban areas. Further surveys should be conducted in farms and their surroundings in order to unravel the role of wild micromammals in the epidemiology of such protozoan parasites affecting our livestock, and therefore human population.


Assuntos
Coccidiose/veterinária , Mamíferos/parasitologia , Infecções Protozoárias em Animais/parasitologia , Sarcocystidae/genética , Animais , Coccidiose/epidemiologia , Coccidiose/parasitologia , DNA de Protozoário/genética , DNA de Protozoário/isolamento & purificação , Genótipo , Mamíferos/classificação , Encistamento de Parasitas , Filogenia , Infecções Protozoárias em Animais/epidemiologia , Sarcocystidae/classificação , Sarcocystidae/isolamento & purificação , Espanha/epidemiologia
19.
Parasitol Res ; 119(12): 4049-4059, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33057815

RESUMO

Neospora caninum is an apicomplexan protozoan and a major cause of abortion in cattle worldwide. In the Argentinian Humid Pampa, bovine neosporosis causes severe economic losses. Despite this, information on the genetic structure of N. caninum in this region is limited. Therefore, this study aimed to genetically characterize N. caninum isolates associated with bovine abortion in the Humid Pampa region. For this purpose, spontaneous bovine fetal tissues submitted for diagnosis to the Veterinary Diagnostic Service at INTA Balcarce during 2008-2019 were assessed by PCR, indirect fluorescent antibody test (IFAT), and histologic analysis. PCR-positive samples were tested by multilocus microsatellite genotyping (MLGs) using 9 microsatellite markers. Thirty-one different genotypes were identified from 32 samples with at least seven markers. Argentinian MLGs were grouped into two clonal clusters when analyzed using eBURST network and principal coordinate analysis. No segregation based on the year of collection, animal biotype, or geographic origin was observed. In addition, the presence of linkage disequilibrium supported the clonal propagation of Argentinian MLGs. One Argentinian subpopulation was associated with isolates from Spain, Uruguay, Brazil, and Mexico, and the other one was linked to isolates from Scotland, Spain, and Germany. These findings reveal the presence of two clonal subpopulations of N. caninum in the Humid Pampa.


Assuntos
Doenças dos Bovinos/parasitologia , Coccidiose/veterinária , Repetições de Microssatélites/genética , Neospora/genética , Animais , Argentina , Bovinos , Doenças dos Bovinos/genética , Feminino , Feto , Técnica Indireta de Fluorescência para Anticorpo , Variação Genética/genética , Genótipo , Desequilíbrio de Ligação/genética , Neospora/imunologia , Reação em Cadeia da Polimerase , Gravidez
20.
Emerg Infect Dis ; 25(6): 1226-1227, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31107232

RESUMO

Low antibody titers to Neospora caninum have been reported in humans, but infection has not been confirmed. We used N. caninum-specific PCR to test 600 clinical samples from patients with toxoplasmosis signs but Toxoplasma gondii-negative PCR results. We did not detect N. caninum DNA, demonstrating it is an unlikely opportunistic zoonotic agent.


Assuntos
Coccidiose/epidemiologia , Coccidiose/parasitologia , DNA de Protozoário , Neospora/genética , Humanos , Reação em Cadeia da Polimerase , Vigilância em Saúde Pública , Espanha/epidemiologia
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