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1.
Med Mycol ; 62(1)2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38142226

RESUMO

Aspergillosis of the newborn remains a rare but severe disease. We report four cases of primary cutaneous Aspergillus flavus infections in premature newborns linked to incubators contamination by putative clonal strains. Our objective was to evaluate the ability of matrix-assisted laser desorption/ionisation time of flight (MALDI-TOF) coupled to convolutional neural network (CNN) for clone recognition in a context where only a very small number of strains are available for machine learning. Clinical and environmental A. flavus isolates (n = 64) were studied, 15 were epidemiologically related to the four cases. All strains were typed using microsatellite length polymorphism. We found a common genotype for 9/15 related strains. The isolates of this common genotype were selected to obtain a training dataset (6 clonal isolates/25 non-clonal) and a test dataset (3 clonal isolates/31 non-clonal), and spectra were analysed with a simple CNN model. On the test dataset using CNN model, all 31 non-clonal isolates were correctly classified, 2/3 clonal isolates were unambiguously correctly classified, whereas the third strain was undetermined (i.e., the CNN model was unable to discriminate between GT8 and non-GT8). Clonal strains of A. flavus have persisted in the neonatal intensive care unit for several years. Indeed, two strains of A. flavus isolated from incubators in September 2007 are identical to the strain responsible for the second case that occurred 3 years later. MALDI-TOF is a promising tool for detecting clonal isolates of A. flavus using CNN even with a limited training set for limited cost and handling time.


Cutaneous aspergillosis is a rare but potentially fatal disease of the prematurely born infant. We described here several cases due to Aspergillus flavus and have linked them to environnemental strains using MLP genotyping and MALDI-TOF mass spectrometry coupled with artificial intelligence.


Assuntos
Aspergilose , Infecção Hospitalar , Animais , Aspergillus flavus/genética , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/veterinária , Infecção Hospitalar/veterinária , Unidades de Terapia Intensiva Neonatal , Aspergilose/diagnóstico , Aspergilose/veterinária
2.
J Clin Microbiol ; 61(10): e0035423, 2023 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-37728898

RESUMO

This study aimed to evaluate different serological strategies for the postnatal diagnosis of congenital toxoplasmosis (CT) and establish a biological algorithm for CT diagnosis. The study analyzed serological data of immunoglobulins M, A, and G (IgM, IgA, IgG) performed by immunoenzymatic and compared immunological profile (CIP) assays in 668 newborns with CT diagnosis across four testing periods: P1 (D0- D10), P2 (D11-D35), P3 (D36-D45), and P4 (>D45). Forty-nine percent of the 668 CT cases were diagnosed during P1 and 34%, 4%, and 12% during P2, P3, and P4, respectively. CIP assays detected neosynthetized IgMs/IgGs in 98% of CT cases diagnosed during P1, while IgMs and IgAs were detected in 90% and 57% of CT cases diagnosed during P2 and in 88% and 67% of diagnoses made during P3, respectively. Detection of neosynthesized IgMs/IgGs, IgMs, and IgAs by immunoassay contributed to CT diagnosis in 81%, 77%, and 60% of cases, respectively. In total, 46% of serum samples were positive for all three parameters, 27% for two, and 27% for one of the three. The study recommends using the CIP assay as standard during P1 for CT diagnosis and IgM and IgA immunoassays after P1. A clinical and biological follow-up in a specialized center with a close collaboration between biologists and clinicians is highly recommended to increase the chances of early diagnosis. Overall, this study provides useful information for the development of a biological algorithm for CT diagnosis, which can aid in early detection and appropriate treatment of this disease.


Assuntos
Toxoplasma , Toxoplasmose Congênita , Recém-Nascido , Humanos , Toxoplasmose Congênita/diagnóstico , Estudos Retrospectivos , Anticorpos Antiprotozoários , Imunoglobulina M , Imunoglobulina G , Imunoglobulina A
3.
Antimicrob Agents Chemother ; 66(1): e0109821, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-34633849

RESUMO

Toxoplasmosis is a worldwide parasitosis that affects one-third of the population. People at risk, such as immunocompromised patients (AIDS, chemotherapy treatment) or fetuses (maternal-fetal transmission) can develop severe forms of the disease. The antiparasitic activity of extracts of different polarities (n-heptane, MeOH, MeOH/H2O) of 10 tree species endemic to temperate regions was investigated against Toxoplasma gondii infection in vitro. Our results showed that the n-heptane extract of the black alder (Alnus glutinosa) exhibited a significant antiparasitic activity without any cytotoxicity at the tested concentrations, with an IC50 of up to 25.08 µg/mL and a selectivity index higher than 3.99. The chemical profiling of this extract revealed triterpenes as major constituents. The ability of commercially available triterpene (betulin, betulinic acid, and betulone) to inhibit the growth of T. gondii was evaluated and showed growth inhibition rates of 44%, 49%, and 99% at 10 µM, respectively.


Assuntos
Alnus , Toxoplasma , Triterpenos , Antiparasitários/farmacologia , Humanos , Casca de Planta , Extratos Vegetais/farmacologia , Triterpenos/farmacologia
4.
J Appl Microbiol ; 132(1): 736-746, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34152060

RESUMO

AIMS: The protozoan parasites Cryptosporidium spp., Giardia duodenalis and Toxoplasma gondii are identified as public health priorities and are present in a wide variety of environments including the marine ecosystem. The objective of this study was to demonstrate that the marine bivalve blue mussel (Mytilus edulis) can be used as a tool to monitor the contamination of marine waters by the three protozoa over time. METHODS AND RESULTS: In order to achieve a proof of concept, mussels were exposed to three concentrations of G. duodenalis cysts and Cryptosporidium parvum/T. gondii oocysts for 21 days, followed by 21 days of depuration in clear water. Then, natural contamination by these protozoa was sought for in wild marine blue mussels along the northwest coast of France to validate their relevance as bioindicators in the field. Our results highlighted that: (a) blue mussels bioaccumulated the parasites for 21 days, according to the conditions of exposure, and parasites could still be detected during the depuration period (until 21 days); (b) the percentage of protozoa-positive M. edulis varied under the degree of protozoan contamination in water; (c) mussel samples from eight out of nine in situ sites were positive for at least one of the protozoa. CONCLUSIONS: The blue mussel M. edulis can bioaccumulate protozoan parasites over long time periods, according to the degree of contamination of waters they are inhabiting, and can highlight recent but also past contaminations (at least 21 days). SIGNIFICANCE AND IMPACT OF THE STUDY: Mytilus edulis is a relevant bioaccumulators of protozoan (oo)cysts in laboratory and field conditions, hence its potential use for monitoring parasite contamination in marine waters.


Assuntos
Criptosporidiose , Cryptosporidium , Mytilus edulis , Animais , Ecossistema , Biomarcadores Ambientais , Laboratórios , Água
5.
Food Microbiol ; 102: 103870, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34809958

RESUMO

The protozoan parasites Cryptosporidium spp., Giardia duodenalis and Toxoplasma gondii can be transmitted to humans through shellfish consumption. No standardized methods are available for their detection in these foods, and the performance of the applied methods are rarely described in occurrence studies. Through spiking experiments, we characterized different performance criteria (e.g. sensitivity, estimated limit of detection (eLD95METH), parasite DNA recovery rates (DNA-RR)) of real-time qPCR based-methods for the detection of the three protozoa in mussel's tissues and hemolymph. Digestion of mussels tissues by trypsin instead of pepsin and the use of large buffer volumes was the most efficient for processing 50g-sample. Trypsin digestion followed by lipids removal and DNA extraction by thermal shocks and a BOOM-based technique performed poorly (e.g. eLD95METH from 30 to >3000 parasites/g). But trypsin digestion and direct DNA extraction by bead-beating and FastPrep homogenizer achieved higher performance (e.g. eLD95METH: 4-400 parasites/g, DNA-RR: 19-80%). Direct DNA recovery from concentrated hemolymph, by thermal shocks and cell lysis products removal was not efficient to sensitively detect the protozoa (e.g. eLD95METH: 10-1000 parasites/ml, DNA-RR ≤ 24%). The bead-beating DNA extraction based method is a rapid and simple approach to sensitively detect the three protozoa in mussels using tissues, that can be standardized to different food matrices. However, quantification in mussels remains an issue.


Assuntos
Cryptosporidium parvum , DNA de Protozoário/isolamento & purificação , Giardia lamblia , Mytilus edulis , Toxoplasma , Animais , Cryptosporidium parvum/genética , DNA de Protozoário/genética , Giardia lamblia/genética , Hemolinfa , Mytilus edulis/parasitologia , Alimentos Marinhos/parasitologia , Toxoplasma/genética , Tripsina
6.
Parasitol Res ; 120(2): 593-603, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33415386

RESUMO

Toxoplasma gondii is a widespread zoonotic protozoan that infects most species of mammals and birds, including poultry. This study aimed to investigate the course of T. gondii infection and the efficacy of diclazuril and Artemisia annua in preventing infection in experimentally infected chickens. Seventy-five 1-month-old chickens, female and male, were randomly divided into five groups (n = 15 each) as follows: (1) uninfected untreated (negative control, NC); (2) infected with T. gondii genotype II/III isolated from a wild cat (group WC); (3) infected with T. gondii genotype II isolated from a domestic cat (group DC); (4) infected with T. gondii domestic cat strain and treated with the anticoccidial diclazuril (group DC-D); and (5) infected with T. gondii domestic cat strain and treated with the medicinal plant Artemisia annua (group DC-A). Clinical signs, body temperature, mortality rate, weight gain, feed conversion ratio, hematological parameters, and the presence of T. gondii-specific IgY antibodies were recorded in all groups. Five chickens per group were euthanized 28 days post-infection (p.i.) and their brains, hearts, and breast muscle tested for T. gondii by mouse bioassay and polymerase chain reaction (PCR). No clinical signs related to the experimental infection were observed throughout the study period. T. gondii-specific antibodies were detected by day 28 p.i., but not in all infected chickens. Overall, T. gondii DNA was detected (bioassay or tissue digests) in all infected and untreated chickens (10/10), while viable parasite (bioassay) was isolated from 7 out of 10 chickens. The parasite was most frequently identified in the brain (7/10). There were no differences in the T. gondii strains regarding clinical infection and the rate of T. gondii detection in tissues. However, higher antibody titers were obtained in chickens infected with T. gondii WC strain (1:192) comparing with T. gondii DC strain (1:48). A. annua reduced replication of the parasite in 3 out of 5 chickens, while diclazuril did not. In conclusion, broiler chickens were resistant to clinical toxoplasmosis, irrespective of the strain (domestic or wild cat strain). The herb A. annua presented prophylactic efficacy by reduced parasite replication. However, further studies are required aiming at the efficacy of diclazuril and A. annua for the prevention of T. gondii infection in chickens using quantitative analysis methods.


Assuntos
Anticorpos Antiprotozoários/imunologia , Artemisia annua , Coccidiostáticos/farmacologia , Nitrilas/farmacologia , Doenças das Aves Domésticas/prevenção & controle , Toxoplasma/imunologia , Toxoplasmose Animal/prevenção & controle , Triazinas/farmacologia , Animais , Encéfalo/parasitologia , Gatos , Galinhas , Feminino , Genótipo , Coração/parasitologia , Masculino , Camundongos , Músculos Peitorais/parasitologia , Plantas Medicinais , Doenças das Aves Domésticas/tratamento farmacológico , Doenças das Aves Domésticas/parasitologia , Distribuição Aleatória , Soroconversão , Distribuição Tecidual , Toxoplasma/genética , Toxoplasma/fisiologia , Toxoplasmose Animal/tratamento farmacológico , Toxoplasmose Animal/parasitologia
7.
Euro Surveill ; 26(5)2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33541484

RESUMO

BackgroundToxoplasmosis during pregnancy can result in congenital anomalies or fetal death. Universal antenatal screening is recommended in France, a strategy in place since the 1970s.AimWe determined the seroprevalence of toxoplasmosis among pregnant women participating in the 2016 national perinatal survey (ENP), compared results with previous ENPs, and investigated factors associated with Toxoplasma gondii infection.MethodsUsing the 2016 ENP data, which contain sociodemographic and clinical information from all women giving birth during a one week period, we calculated adjusted prevalence ratios (aPR) by sociodemographic factors. Using available data from prior ENPs (1995, 2003 and 2010), we calculated age-standardised seroprevalences and aPRs for French women.ResultsIn 2016, seroprevalence was 31.3% overall. Among French women, associations with increasing age (aPR: 1.54; 95% CI: 1.39-1.70), residence in Paris (aPR: 1.19; 95% CI: 1.08-1.31) or south-western regions (aPR: 1.19; 95% CI: 1.08-1.31), and higher professional status (aPR: 1.12; 95%CI 1.04-1.21) were observed. An association with increasing age was also evident among women from North Africa and sub-Saharan Africa. Age-standardised seroprevalence decreased from 55.0% in 1995 to 33.7% in 2016. Among French women, significant associations with age, Paris and south-west regions persisted across all ENPs.ConclusionHigher prevalences in older women may reflect a higher past risk of exposure while persistent geographical differences may reflect dietary or environmental differences. Toxoplasma seroprevalence among pregnant women continues to fall and will impact screening effectiveness. This warrants a comprehensive review to determine the appropriate future of prevention in France.


Assuntos
Toxoplasma , Toxoplasmose , África do Norte , Idoso , Anticorpos Antiprotozoários , Estudos Transversais , Feminino , França/epidemiologia , Humanos , Paris , Políticas , Gravidez , Gestantes , Fatores de Risco , Estudos Soroepidemiológicos , Toxoplasmose/diagnóstico , Toxoplasmose/epidemiologia
8.
Int J Mol Sci ; 22(14)2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34299110

RESUMO

Molecular docking is widely used in computed drug discovery and biological target identification, but getting fast results can be tedious and often requires supercomputing solutions. AMIDE stands for AutoMated Inverse Docking Engine. It was initially developed in 2014 to perform inverse docking on High Performance Computing. AMIDE version 2 brings substantial speed-up improvement by using AutoDock-GPU and by pulling a total revision of programming workflow, leading to better performances, easier use, bug corrections, parallelization improvements and PC/HPC compatibility. In addition to inverse docking, AMIDE is now an optimized tool capable of high throughput inverse screening. For instance, AMIDE version 2 allows acceleration of the docking up to 12.4 times for 100 runs of AutoDock compared to version 1, without significant changes in docking poses. The reverse docking of a ligand on 87 proteins takes only 23 min on 1 GPU (Graphics Processing Unit), while version 1 required 300 cores to reach the same execution time. Moreover, we have shown an exponential acceleration of the computation time as a function of the number of GPUs used, allowing a significant reduction of the duration of the inverse docking process on large datasets.


Assuntos
Algoritmos , Ensaios de Triagem em Larga Escala/métodos , Simulação de Acoplamento Molecular , Preparações Farmacêuticas/química , Proteínas/química , Software , Gráficos por Computador , Humanos , Ligantes , Reprodutibilidade dos Testes , Fluxo de Trabalho
9.
Parasitology ; 147(5): 516-532, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31965956

RESUMO

One of the ways of human parasitic infection is the accidental ingestion of vegetables contaminated with parasites, which represents a major human health hazard. This non-exhaustive review aims to evaluate studies carried out on five types of vegetables (lettuce, parsley, coriander, carrot and radish) since 2000, particularly the methods used for recovery, concentration, detection and identification of protozoan parasites such as Toxoplasma gondii, Giardia duodenalis and Cryptosporidium spp., and the results of each work. Various studies have determined the presence of pathogenic parasites in fresh vegetables with different rates; this variation in rate depends particularly on the detection method used which is related to each parasite and each vegetable type. The variation in parasitic prevalence in food could be due to different factors such as the geographical location, the size of analysed samples and the methods used for parasite detection.


Assuntos
Contaminação de Alimentos , Doenças Parasitárias/transmissão , Verduras/parasitologia , Animais , Criptosporidiose/transmissão , Cryptosporidium/isolamento & purificação , Giardia/isolamento & purificação , Giardíase/transmissão , Parasitos/isolamento & purificação , Prevalência , Toxoplasma/isolamento & purificação , Toxoplasmose/transmissão
10.
Prenat Diagn ; 40(13): 1741-1752, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32506432

RESUMO

OBJECTIVE: To describe the lesions detected by prenatal ultrasound examination in congenital toxoplasmosis (CT). METHODS: We retrospectively analyzed all cases of fetal infection with Toxoplasma gondii with ultrasound anomalies described by fetal medicine experts in 2009 to 2019 in 30 French centers. RESULTS: Eighty-eight cases of CT were included. Forty-five (51.1%) had one or more cerebral signs only, 35 (39.8%) had cerebral plus extracerebral signs and 8 (9.1%) had extracerebral signs only. The main cerebral signs were intracranial hyperechogenic nodular foci (n = 60) of which 20 were isolated, ventriculomegalies (n = 44) which generally increased during follow-up, and periventricular abscesses (n = 12). The main extracerebral signs were hepatomegaly and/or splenomegaly (n = 14), small for gestational age (n = 14), ascites (n = 14, including 2 with hydrops), and hyperechogenic bowel (n = 11). Maternal infection occurred mostly in the first or second trimester (81 cases), periconceptionally in one and in the third trimester in six cases. The first ultrasound signs were detected after a median of 7 weeks (range: 1.4; 24.0) following maternal toxoplasmosis seroconversion. CONCLUSION: While no sign was specific of CT, there were typical associations of cerebral signs with or without extracerebral signs. Detailed ultrasound examination could improve prognostic evaluation, as well as diagnosis of CT in settings lacking serological screening.


Assuntos
Doenças Fetais/diagnóstico por imagem , Complicações Infecciosas na Gravidez/diagnóstico por imagem , Toxoplasmose Congênita/diagnóstico por imagem , Ultrassonografia Pré-Natal , Feminino , Humanos , Gravidez , Estudos Retrospectivos
11.
Planta Med ; 86(4): 294-302, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31994148

RESUMO

Toxoplasma gondii, belonging to the Apicomplexa phylum, is a cosmopolitan protozoan parasite that affects at least 30% of the world's population. In West Africa, the leaves and bark of the tree species Anogeissus leiocarpa (DC.) Guill. & Perr. are used against zoonosis in traditional medicine and play a key role in controlling diseases induced by Apicomplexans such as malaria. In this study, extracts, fractions, and pure compounds obtained from an ethanol extract of the bark of A. leiocarpa were evaluated against T. gondii infection in vitro and in vivo. The crude bark extract showed significant activity on tachyzoites from the T. gondii RH strain (IC50 = 59.30 µg/mL). The crude bark extract without tannins and pure trachelosperogenin E purified by centrifugal partition chromatography showed the highest activity (IC50s = 12.83 and 26.63 µg/mL, respectively) with satisfying selectivity indexes of 9.61 and 9.75, respectively. The crude bark extract without tannins and pure trachelosperogenin E were able to significantly inhibit host cell invasion by the parasite in vitro, while the crude bark extract without tannins was able to increase mice survival in our murine model of chronic toxoplasmosis. These results provide new biological data for natural compounds that could enhance the current panoply of treatments against toxoplasmosis.


Assuntos
Malária , Toxoplasma , Animais , Camundongos , Casca de Planta , Extratos Vegetais , Folhas de Planta
12.
Appl Environ Microbiol ; 85(20)2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31399406

RESUMO

Toxoplasma gondii is a ubiquitous foodborne protozoan that can infect humans at low dose and displays different prevalences among countries in the world. Ingestion of food or water contaminated with small amounts of T. gondii oocysts may result in human infection. However, there are no regulations for monitoring oocysts in food, mainly because of a lack of standardized methods to detect them. The objectives of this study were (i) to develop a reliable method, applicable in biomonitoring, for the rapid detection of infectious oocysts by cell culture of their sporocysts combined with quantitative PCR (sporocyst-CC-qPCR) and (ii) to adapt this method to blue and zebra mussels experimentally contaminated by oocysts with the objective to use these organisms as sentinels of aquatic environments. Combining mechanical treatment and bead beating leads to the release of 84% ± 14% of free sporocysts. The sporocyst-CC-qPCR detected fewer than ten infectious oocysts in water within 4 days (1 day of contact and 3 days of cell culture) compared to detection after 4 weeks by mouse bioassay. For both mussel matrices, oocysts were prepurified using a 30% Percoll gradient and treated with sodium hypochlorite before cell culture of their sporocysts. This assay was able to detect as few as ten infective oocysts. This sporocyst-based CC-qPCR appears to be a good alternative to mouse bioassay for monitoring infectious T. gondii oocysts directly in water and also using biological sentinel mussel species. This method offers a new perspective to assess the environmental risk for human health associated with this parasite.IMPORTANCE The ubiquitous protozoan Toxoplasma gondii is the subject of renewed interest due to the spread of oocysts in water and food causing endemic and epidemic outbreaks of toxoplasmosis in humans and animals worldwide. Displaying a sensitivity close to animal models, cell culture represents a real alternative to assess the infectivity of oocysts in water and in biological sentinel mussels. This method opens interesting perspectives for evaluating human exposure to infectious T. gondii oocysts in the environment, where oocyst amounts are considered to be very small.


Assuntos
Oocistos/genética , Oocistos/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real/métodos , Toxoplasma/genética , Toxoplasma/isolamento & purificação , Toxoplasmose/parasitologia , Animais , Bioensaio , Bivalves , Técnicas de Cultura de Células/métodos , DNA de Protozoário/análise , Modelos Animais de Doenças , Monitoramento Ambiental , Feminino , Alimentos , Camundongos , Água/parasitologia , Doenças Transmitidas pela Água/parasitologia
13.
Parasitol Res ; 118(3): 999-1010, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30729299

RESUMO

Information on the viability of Toxoplasma gondii oocysts is crucial to establish the public health significance of this environmental transmission stage that can contaminate water and foods. Interest for molecular-based methods to assess viability is growing and the aim of our study was to assess, for the first time, a propidium monoazide (PMA)-qPCR approach to determine the viability of T. gondii oocysts. Untreated and heat-killed (99 °C, 5 min) oocysts were incubated with PMA, a photoreactive DNA binding dye, and analyzed by confocal microscopy and flow cytometry to characterize oocysts' dye permeability. Different PMA concentrations (50 to 150 µM), incubation temperatures (22, 37, and 45 °C), amplicon length, selected targeted gene, and dyes (PMA, PMAxx™) were evaluated to define optimal conditions to discriminate specifically viable oocysts by PMA-qPCR. In theory, PMA binding to DNA would inhibit PCR amplification in dead but not in viable oocysts. Incubation at 22 °C with 100 µM PMA coupled to qPCR targeting a 123-bp sequence of the 529-bp repeat element allowed the distinction between viable and heated oocysts. However, the reduction of viability following heating of oocysts at high temperature was slight and, contrarily to reverse transcriptase-qPCR, the qPCR signal was not totally suppressed in heated suspensions. Therefore, PMA-qPCR is able to assess the impact of heating on T. gondii oocysts' viability but underestimates the efficacy of this treatment. The relevance of this technique to evaluate the efficacy of other inactivation processes and assess exposure of humans to this pathogen requires further investigations.


Assuntos
Azidas/química , Oocistos/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Propídio/análogos & derivados , Toxoplasma/isolamento & purificação , Corantes , Humanos , Viabilidade Microbiana , Propídio/química , Coloração e Rotulagem , Toxoplasma/fisiologia
14.
Emerg Infect Dis ; 24(8): 1497-1504, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30014843

RESUMO

Transplantation activity is increasing, leading to a growing number of patients at risk for toxoplasmosis. We reviewed toxoplasmosis prevention practices, prevalence, and outcomes for hematopoietic stem cell transplant (HSCT) and solid organ transplant (SOT; heart, kidney, or liver) patients in Europe. We collected electronic data on the transplant population and prevention guidelines/regulations and clinical data on toxoplasmosis cases diagnosed during 2010-2014. Serologic pretransplant screening of allo-hematopoietic stem cell donors was performed in 80% of countries, screening of organ donors in 100%. SOT recipients were systematically screened in 6 countries. Targeted anti-Toxoplasma chemoprophylaxis was heterogeneous. A total of 87 toxoplasmosis cases were recorded (58 allo-HSCTs, 29 SOTs). The 6-month survival rate was lower among Toxoplasma-seropositive recipients and among allo-hematopoietic stem cell and liver recipients. Chemoprophylaxis improved outcomes for SOT recipients. Toxoplasmosis remains associated with high mortality rates among transplant recipients. Guidelines are urgently needed to standardize prophylactic regimens and optimize patient management.


Assuntos
Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Órgãos/efeitos adversos , Toxoplasmose/epidemiologia , Toxoplasmose/etiologia , Adulto , Europa (Continente)/epidemiologia , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Transplantados
15.
Artigo em Inglês | MEDLINE | ID: mdl-29133550

RESUMO

Toxoplasma gondii is a cosmopolitan protozoan parasite which affects approximately 30% of the population worldwide. The drugs currently used against toxoplasmosis are few in number and show several limitations, such as drug intolerance, poor bioavailability, or drug resistance mechanism developed by the parasite. Thus, it is important to find new compounds able to inhibit parasite invasion or proliferation. In this study, the 400 compounds of the open-access Pathogen Box, provided by the Medicines for Malaria Venture (MMV) foundation, were screened for their anti-Toxoplasma gondii activity. A preliminary in vitro screening performed over 72 h by an enzyme-linked immunosorbent assay (ELISA) revealed 15 interesting compounds that were effective against T. gondii at 1 µM. Their cytotoxicity was estimated on Vero cells, and their 50% inhibitory concentrations (IC50) were further calculated. As a result, eight anti-Toxoplasma gondii compounds with an IC50 of less than 2 µM and a selectivity index (SI) value of greater than 4 were identified. The most active was MMV675968, showing an IC50 of 0.02 µM and a selectivity index value equal to 275. Two other compounds, MMV689480 and MMV687807, also showed a good activity against T. gondii, with IC50s of 0.10 µM (SI of 86.6) and 0.15 µM (SI of 11.3), respectively. Structure-activity relationships for the eight selected compounds also were discussed on the basis of fingerprinting similarity measurements using the Tanimoto method. The anti-Toxoplasma gondii compounds highlighted here represent potential candidates for the development of new drugs that could be used against toxoplasmosis.


Assuntos
Antiparasitários/farmacologia , Toxoplasma/efeitos dos fármacos , Toxoplasmose/tratamento farmacológico , Animais , Linhagem Celular , Chlorocebus aethiops , Concentração Inibidora 50 , Relação Estrutura-Atividade , Toxoplasmose/parasitologia , Células Vero
16.
Am J Obstet Gynecol ; 219(4): 386.e1-386.e9, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29870736

RESUMO

BACKGROUND: The efficacy of prophylaxis to prevent prenatal toxoplasmosis transmission is controversial, without any previous randomized clinical trial. In France, spiramycin is usually prescribed for maternal seroconversions. A more potent pyrimethamine + sulfadiazine regimen is used to treat congenital toxoplasmosis and is offered in some countries as prophylaxis. OBJECTIVE: We sought to compare the efficacy and tolerance of pyrimethamine + sulfadiazine vs spiramycin to reduce placental transmission. STUDY DESIGN: This was a randomized, open-label trial in 36 French centers, comparing pyrimethamine (50 mg qd) + sulfadiazine (1 g tid) with folinic acid vs spiramycin (1 g tid) following toxoplasmosis seroconversion. RESULTS: In all, 143 women were randomized from November 2010 through January 2014. An amniocentesis was later performed in 131 cases, with a positive Toxoplasma gondii polymerase chain reaction in 7/67 (10.4%) in the pyrimethamine + sulfadiazine group vs 13/64 (20.3%) in the spiramycin group. Cerebral ultrasound anomalies appeared in 0/73 fetuses in the pyrimethamine + sulfadiazine group, vs 6/70 in the spiramycin group (P = .01). Two of these pregnancies were terminated. Transmission rates, excluding 18 children with undefined status, were 12/65 in the pyrimethamine + sulfadiazine group (18.5%), vs 18/60 in the spiramycin group (30%, P = .147), equivalent to an odds ratio of 0.53 (95% confidence interval, 0.23-1.22) and which after adjustment tended to be stronger (P = .03 for interaction) when treatment started within 3 weeks of seroconversion (95% confidence interval, 0.00-1.63). Two women had severe rashes, both with pyrimethamine + sulfadiazine. CONCLUSION: There was a trend toward lower transmission with pyrimethamine + sulfadiazine, but it did not reach statistical significance, possibly for lack of statistical power because enrollment was discontinued. There were also no fetal cerebral toxoplasmosis lesions in the pyrimethamine + sulfadiazine group. These promising results encourage further research on chemoprophylaxis to prevent congenital toxoplasmosis.


Assuntos
Antiprotozoários/uso terapêutico , Complicações Infecciosas na Gravidez/tratamento farmacológico , Toxoplasmose/tratamento farmacológico , Adulto , Antiprotozoários/administração & dosagem , Quimioterapia Combinada , Feminino , França , Humanos , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Gravidez , Cuidado Pré-Natal , Pirimetamina/administração & dosagem , Pirimetamina/uso terapêutico , Sulfadiazina/administração & dosagem , Sulfadiazina/uso terapêutico , Toxoplasmose/transmissão , Toxoplasmose Congênita/prevenção & controle , Resultado do Tratamento
17.
Mycopathologia ; 183(3): 573-577, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28681316

RESUMO

We report here a case of possible donor-derived Candida stellimalicola infection after pancreas transplantation. Candida stellimalicola, an environmental non-filamentous yeast, was isolated from both the peritoneal fluid of the graft donor and the preservation fluid of the transplanted pancreas. Interestingly, this strain exhibited high minimum inhibitory concentrations to azoles. These results justified the use of echinocandins as therapy instead of fluconazole. This switch permitted a favorable outcome. To our knowledge, this is the first report of C. stellimalicola from clinical samples and therefore the first reported case of a possible human infection. This case report highlights the need for standardized microbiological procedures in solid organ transplant settings. Moreover, it underlines the importance of using molecular identification technique when routine techniques do not allow successful identification of the pathogen. It is of utmost importance to determine sensitivity profile, even in the absence of species-level identification, because resistance to fluconazole is not uncommon, especially in emergent species.


Assuntos
Candida/isolamento & purificação , Candidíase/diagnóstico , Candidíase/transmissão , Transmissão de Doença Infecciosa , Transplante de Pâncreas/efeitos adversos , Adulto , Antifúngicos/administração & dosagem , Antifúngicos/farmacologia , Líquido Ascítico/microbiologia , Candida/classificação , Candidíase/microbiologia , Candidíase/patologia , Feminino , Humanos , Testes de Sensibilidade Microbiana , Doadores de Tecidos , Transplantados , Resultado do Tratamento
18.
Folia Parasitol (Praha) ; 652018 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-29528299

RESUMO

The faeces of the red fox, Vulpes vulpes (Linnaeus), and the domestic cat, Felis catus (Linnaeus), can be responsible for spreading eggs of Echinococcus multilocularis Leuckart, 1863 and oocysts of Toxoplasma gondii (Nicolle et Manceaux, 1908) into the environment. The accidental ingestion of these eggs or oocysts, through consumption of raw fruits or vegetables grown in or in contact with contaminated soil, can lead to alveolar echinococcosis (AE) or toxoplasmosis in humans. The present study provides a quantitative assessment of the faecal deposition by foxes and cats in kitchen gardens where fruits and vegetables are grown and its consequences for zoonosis transmission. The density of definitive host faeces is considered as one of the main factors in infection risk for intermediate hosts. The density of fox and cat faeces, as well as the prevalence of both AE and toxoplasmosis in rodent populations (contaminated by ingestion of eggs or oocysts), were compared within and outside kitchen gardens. Our results showed that the mean density of fox faeces did not significantly differ between kitchen gardens and habitat edges (0.29 ± 0.04 faeces/m2 vs 0.22 ± 0.02 faeces/m2), the latter being known as an area of high fox faeceal densities. The density of cat faeces was significantly higher within the kitchen garden than outside (0.86 ± 0.22 faeces/m2 vs 0.04 ± 0.02 faeces/m2). The sampled kitchen gardens might therefore be considered as possible hotspots for both fox and cat defecation. Of the 130 rodents trapped, 14% were infected by at least one species of fox or cat intestinal parasite. These rodents were significantly more often infected when they were exposed to a kitchen garden. These results suggest that the deposit of fox and cat faeces in kitchen gardens would significantly impact the risk of human exposure to E. multilocularis and T. gondii. and should be prevented using effective means.


Assuntos
Arvicolinae , Equinococose/veterinária , Fezes/parasitologia , Murinae , Doenças dos Roedores/epidemiologia , Toxoplasmose Animal/epidemiologia , Animais , Gatos , Equinococose/epidemiologia , Equinococose/parasitologia , Echinococcus multilocularis/isolamento & purificação , Feminino , Raposas , França/epidemiologia , Jardins , Masculino , Prevalência , Doenças dos Roedores/parasitologia , Toxoplasma/isolamento & purificação , Toxoplasmose Animal/parasitologia
19.
Foodborne Pathog Dis ; 14(5): 269-281, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28186826

RESUMO

Ingestion of undercooked meat has been proposed as an important source of human Toxoplasma gondii infection. To ascertain the contribution of meat consumption to the risk of human infection, estimates of the prevalence of infection in meat-producing animals are required. A cross-sectional study was conducted to assess T. gondii infection in pigs raised in England, to identify risk factors for infection, and to compare performance of two serological tests: modified agglutination test (MAT) and enzyme-linked immunosorbent assay (ELISA). Blood samples from 2071 slaughter pigs originating from 131 farms were collected and 75 (3.6%) were found to be positive by MAT. Positive pigs originated from 24 farms. A subset of samples (n = 492) were tested using ELISA, and a significant disagreement (p < 0.001) was found between the two tests. An empirical Bayes approach was used to estimate the farm-level prevalence and the probability of each individual farm having at least one positive animal, considering the uncertainty arising from the sampling strategy and the imperfect test performance. The adjusted farm-level prevalence was 11.5% (95% credible interval of positive farms 8.4-16.0%). Two different criteria were used for classifying farms as infected: (1) ≥50% probability of having at least one infected pig (n = 5, 6.8%) and (2) ≥10% probability (n = 15, 20.5%). Data on putative risk factors were obtained for 73 farms. Using a 10% cutoff, the relative risk (RR) of infection was higher in farms where cats have direct access to pigs' food (RR = 2.6; p = 0.04), pigs have outdoor access (RR = 3.0; p = 0.04), and farms keeping ≤200 pigs (RR = 3.9; p = 0.02), with strong collinearity between the three variables. The findings suggest a low level of T. gondii infection in the farms studied, most of which are likely to send to slaughter batches comprising 100% uninfected pigs. These results provide key inputs to quantitatively assess the T. gondii risk posed by pork to consumers.


Assuntos
Doenças Transmitidas por Alimentos/epidemiologia , Doenças dos Suínos/epidemiologia , Toxoplasma/isolamento & purificação , Toxoplasmose Animal/epidemiologia , Animais , Anticorpos Antiprotozoários/sangue , Teorema de Bayes , Estudos Transversais , Inglaterra/epidemiologia , Feminino , Contaminação de Alimentos , Parasitologia de Alimentos , Doenças Transmitidas por Alimentos/parasitologia , Masculino , Carne Vermelha/parasitologia , Fatores de Risco , Suínos , Doenças dos Suínos/parasitologia
20.
Bioconjug Chem ; 27(4): 1067-81, 2016 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-26930394

RESUMO

The development of chemically designed matrix metalloprotease (MMP) inhibitors has advanced the understanding of the roles of MMPs in different diseases. Most MMP probes designed are fluorogenic substrates, often suffering from photo- and chemical instability and providing a fluorescence signal of moderate intensity, which is difficult to detect and analyze when dealing with crude biological samples. Here, an inhibitor that inhibits MMP-2 more selectively than Galardin has been synthesized and used for enzyme labeling and detection of the MMP-2 activity. A complete MMP-2 recognition complex consisting of a biotinylated MMP inhibitor tagged with the streptavidin-quantum dot (QD) conjugate has been prepared. This recognition complex, which is characterized by a narrow fluorescence emission spectrum, long fluorescence lifetime, and negligible photobleaching, has been demonstrated to specifically detect MMP-2 in in vitro sandwich-type biochemical assays with sensitivities orders of magnitude higher than those of the existing gold standards employing organic dyes. The approach developed can be used for specific in vitro visualization and testing of MMP-2 in cells and tissues with sensitivities significantly exceeding those of the best existing fluorogenic techniques.


Assuntos
Metaloproteinase 2 da Matriz/efeitos dos fármacos , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , Pontos Quânticos , Desenho de Fármacos
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