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1.
J Colloid Interface Sci ; 588: 401-417, 2021 Apr 15.
Article in English | MEDLINE | ID: mdl-33422789

ABSTRACT

HYPOTHESIS: The implementation of the proposal from the European Chemical Agency (ECHA) to restrict the use of nanoplastics (NP) and microplastics (MP) in consumer products will require reliable methods to perform size and mass-based concentration measurements. Analytical challenges arise at the nanometre to micrometre interface, e.g., 800 nm-10 µm, where techniques applicable at the nanometre scale reach their upper limit of applicability and approaches applicable at the micrometre scale must be pushed to their lower limits of detection. EXPERIMENTS: Herein, we compared the performances of nine analytical techniques by measuring the particle size distribution and mass-based concentration of polystyrene mixtures containing both nano and microparticles, with the educational aim to underline applicability and limitations of each technique. FINDINGS: Light scattering-based measurements do not have the resolution to distinguish multiple populations in polydisperse samples. Nanoparticle tracking analysis (NTA), nano-flowcytometry (nFCM) and asymmetric flow field flow fractionation hyphenated with multiangle light scattering (AF4-MALS) cannot measure particles in the micrometre range. Static light scattering (SLS) is not able to accurately detect particles below 200 nm, and similarly to transmission electron microscopy (TEM) and flow cytometry (FCM), is not suitable for accurate mass-based concentration measurements. Alternatives for high-resolution sizing and concentration measurements in the size range between 60 nm and 5 µm are tunable resistive pulse sensing (TRPS) and centrifugal liquid sedimentation (CLS), that can bridge the gap between the nanometre and micrometre range.

2.
J Appl Microbiol ; 130(2): 504-515, 2021 Feb.
Article in English | MEDLINE | ID: mdl-32737913

ABSTRACT

AIMS: The study was aimed to understand the depuration process of Cryptosporidium parvum and Toxoplasma gondii oocysts by zebra mussel (Dreissena polymorpha), to consider the use of the zebra mussel as a bioremediation tool. MATERIALS AND METHODS: Two experiments were performed: (i) individual exposure of mussel to investigate oocyst transfers between bivalves and water and (ii) in vivo exposure to assess the ability of the zebra mussel to degrade oocysts. RESULTS: (i) Our results highlighted a transfer of oocysts from the mussels to the water after 3 and 7 days of depuration; however, some oocysts were still bioaccumulated in mussel tissue. (ii) Between 7 days of exposure at 1000 or 10 000 oocysts/mussel/day and 7 days of depuration, the number of bioaccumulated oocysts did not vary but the number of infectious oocysts decreased. CONCLUSION: Results show that D. polymorpha can release oocysts in water via (pseudo)faeces in depuration period. Oocysts remain bioaccumulated and infectious oocyst number decreases during the depuration period in zebra mussel tissues. Results suggest a degradation of bioaccumulated C. parvum and T. gondii oocysts. SIGNIFICANCE AND IMPACT OF THE STUDY: This study highlighted the potential use of D. polymorpha as a bioremediation tool to mitigate of protozoan contamination in water resources.


Subject(s)
Cryptosporidium parvum/physiology , Dreissena/physiology , Toxoplasma/physiology , Animals , Biodegradation, Environmental , Dreissena/parasitology , Oocysts/physiology , Water/parasitology
3.
Int J Parasitol ; 49(7): 515-522, 2019 06.
Article in English | MEDLINE | ID: mdl-31108097

ABSTRACT

In cattle, antibodies to Toxoplasma gondii infection are frequently detected, but evidence for the presence of T. gondii tissue cysts in cattle is limited. To study the concordance between the presence of anti-T. gondii IgG and viable tissue cysts of T. gondii in cattle, serum, liver and diaphragm samples of 167 veal calves and 235 adult cattle were collected in Italy, the Netherlands, Romania and the United Kingdom. Serum samples were tested for anti-T. gondii IgG by the modified agglutination test and p30 immunoblot. Samples from liver were analyzed by mouse bioassay and PCR after trypsin digestion. In addition, all diaphragms of cattle that had tested T. gondii-positive (either in bioassay, by PCR on trypsin-digested liver or serologically by MAT) and a selection of diaphragms from cattle that had tested negative were analyzed by magnetic capture quantitative PCR (MC-PCR). Overall, 13 animals were considered positive by a direct detection method: seven out of 151 (4.6%) by MC-PCR and six out of 385 (1.6%) by bioassay, indicating the presence of viable parasites. As cattle that tested positive in the bioassay tested negative by MC-PCR and vice-versa, these results demonstrate a lack of concordance between the presence of viable parasites in liver and the detection of T. gondii DNA in diaphragm. In addition, the probability to detect T. gondii parasites or DNA in seropositive and seronegative cattle was comparable, demonstrating that serological testing by MAT or p30 immunoblot does not provide information about the presence of T. gondii parasites or DNA in cattle and therefore is not a reliable indicator of the risk for consumers.


Subject(s)
Antibodies, Protozoan/blood , Cattle Diseases/diagnosis , Diagnostic Tests, Routine/methods , Toxoplasma/isolation & purification , Toxoplasmosis, Animal/diagnosis , Animals , Cattle , Cattle Diseases/parasitology , Diaphragm/parasitology , Europe , Immunoassay/methods , Immunoglobulin G/blood , Liver/parasitology , Molecular Diagnostic Techniques/methods , Sensitivity and Specificity , Serum/immunology , Serum/parasitology , Toxoplasmosis, Animal/parasitology
4.
Food Waterborne Parasitol ; 14: e00034, 2019 Mar.
Article in English | MEDLINE | ID: mdl-32095604

ABSTRACT

Preventing foodborne pathogen contamination of raw fruit and vegetables in the field is critically important for public health. Specifically, it involves preventing faecal deposit by wildlife or domestic animals in fields of crops and kitchen gardens. The present study aims to identify the drivers of fox, dog and cat faecal deposits in kitchen gardens in order to mitigate the risk of contamination of raw produce with parasites shed in carnivore faeces. The focus was on Echinococcus multilocularis, ranked highest in the importance of foodborne parasites in Europe, but attention was also paid to other parasites of major concern - Toxoplasma gondii and Toxocara spp. During the winters of 2014 to 2016, faecal samples were collected from 192 kitchen gardens located in north-eastern France. From these samples, 77% contained scat of carnivores. Molecular analyses revealed that 59% of the 1016 faeces collected were from cats, 31% from foxes, and 10% from dogs. The ease of accessibility to kitchen gardens, the presence of food in the vicinity, and the composition of the surrounding vegetation were used to explain the distribution of fox and cat faeces. Generalized Linear Mixed Effects modelling showed that: i) fencing was not efficient in reducing cat faecal deposits, but drastically decreases those of foxes; ii) the abundance of Microtus sp. indicates a reason for the presence of both fox and cat faecal deposits, iii) the abundance of Arvicola terrestris, the proximity of fruit trees or farms and the predominance of forest and grassland around the village are all drivers of fox faecal deposits. These results point to the importance of fencing around kitchen gardens located in E. multilocularis endemic areas, particularly those surrounded by forest and grassland or close to fruit trees or farms.

5.
Bone ; 120: 411-422, 2019 03.
Article in English | MEDLINE | ID: mdl-30529011

ABSTRACT

The two SIBLING (Small Integrin Binding Ligand N-linked Glycoproteins), bone sialoprotein (BSP) and osteopontin (OPN) are expressed in osteoblasts and osteoclasts. In mature BSP knockout (KO, -/-) mice, both bone formation and resorption as well as mineralization are impaired. OPN-/- mice display impaired resorption, and OPN is described as an inhibitor of mineralization. However, OPN is overexpressed in BSP-/- mice, complicating the understanding of their phenotype. We have generated and characterized mice with a double KO (DKO) of OPN and BSP, to try and unravel their respective contributions. Despite the absence of OPN, DKO bones are still hypomineralized. The SIBLING, matrix extracellular phosphoglycoprotein with ASARM motif (MEPE) is highly overexpressed in both BSP-/- and DKO and may impair mineralization through liberation of its ASARM (Acidic Serine-Aspartate Rich MEPE associated) peptides. DKO mice also display evidence of active formation of trabecular, secondary bone as well as primary bone in the marrow-ablation repair model. A higher number of osteoclasts form in DKO marrow cultures, with higher resorption activity, and DKO long bones display a localized and conspicuous cortical macroporosity. High bone formation and resorption parameters, and high cortical porosity in DKO mice suggest an active bone modeling/remodeling, in the absence of two key regulators of bone cell performance. This first double KO of SIBLING proteins thus results in a singular, non-trivial phenotype leading to reconsider the interpretation of each single KO, concerning in particular matrix mineralization and the regulation of bone cell activity.


Subject(s)
Bone Remodeling/physiology , Bone and Bones/physiopathology , Calcification, Physiologic/physiology , Gene Deletion , Integrin-Binding Sialoprotein/deficiency , Osteopontin/deficiency , Animals , Biomarkers/metabolism , Bone Marrow/pathology , Bone Matrix/physiopathology , Cancellous Bone/physiopathology , Cell Differentiation , Extracellular Matrix Proteins/metabolism , Gene Expression Regulation , Integrin-Binding Sialoprotein/metabolism , Mice, Knockout , Osteoblasts/metabolism , Osteoclasts/metabolism , Osteogenesis , Osteopontin/metabolism , Reproducibility of Results
6.
Int J Parasitol ; 48(9-10): 751-762, 2018 08.
Article in English | MEDLINE | ID: mdl-29782830

ABSTRACT

Chickens, especially if free-range, are frequently exposed to Toxoplasma gondii, and may represent an important reservoir for T. gondii. Poultry products may pose a risk to humans, when consumed undercooked. In addition, chickens are regarded as sensitive indicators for environmental contamination with T. gondii oocysts and have been used as sentinels. The aim of the present study was to determine the suitability of commonly used antibody detection methods, i.e. the modified agglutination test (MAT), IFAT and ELISA to detect T. gondii-infected chickens. Samples of experimentally and naturally infected chickens were used. The infection state of all chickens was determined by Magnetic-Capture (MC-) real-time PCR (RT PCR). Naturally exposed chickens were additionally examined by mouse bioassay and conventional RT PCR on acidic pepsin digests (PD-RT PCR). Blood serum and meat juice of various sources were tested for antibodies to T. gondii. In naturally infected chickens, there was substantial agreement between the mouse bioassay and MC-RT PCR or the mouse bioassay and conventional PD-RT PCR. PD-RT PCR was slightly more sensitive than MC-RT PCR, as all (26/26) bioassay-positive chickens also tested positive in at least one of the tissues tested (heart, drumstick). By MC-RT PCR, 92.3% (24/26) of the naturally infected bioassay-positive chickens were positive. The diagnostic sensitivity of MC-RT PCR was clearly related to the organ examined. Based on a quantitative assessment of the MC-RT PCR results in experimentally infected chickens, brain and heart tissues harbored an at least 100 times higher parasite concentration than breast, thigh or drumstick musculature. In naturally infected chickens, only three out of 24 birds, which were MC-RT PCR-positive in heart samples, also tested positive in drumstick musculature. Under experimental conditions, the agreement between MC-RT PCR and the serological techniques revealed 100% diagnostic sensitivity and specificity. Under field conditions, examinations of sera by ELISA, IFAT and MAT showed good performance in identifying chickens that were positive in either a mouse bioassay, MC-RT PCR, or PD-RT PCR as illustrated by diagnostic sensitivities of 87.5%, 87.5% and 65.2%, respectively, and diagnostic specificities of 86.2%, 82.8% and 100%, respectively. The examination of meat juice samples from breast, drumstick or heart musculature revealed similar or even better results in the ELISA. The results in the MAT with meat juice from breast musculature were less consistent than those of ELISA and IFAT because a number of negative chickens tested false-positive in the MAT. The MAT performed similar to ELISA and IFAT when applied to test meat juice samples collected from heart, thigh or drumstick musculature.


Subject(s)
Biological Assay/methods , DNA, Protozoan/isolation & purification , Meat/parasitology , Poultry Diseases/parasitology , Toxoplasma , Toxoplasmosis, Animal/blood , Animals , Chickens , DNA, Protozoan/genetics , Food Parasitology , Mice , Poultry Diseases/blood , Poultry Diseases/diagnosis
7.
Int J Parasitol ; 47(6): 357-367, 2017 05.
Article in English | MEDLINE | ID: mdl-28315671

ABSTRACT

Little information is available on the relationship between the spatial distribution of zoonotic parasites in soil and the pattern of hosts' faeces deposition at a local scale. In this study, the spatial distribution of soil contaminated by the parasite Toxoplasma gondii was investigated in relation to the distribution and use of the defecation sites of its definitive host, the domestic cat (Felis catus). The study was conducted on six dairy farms with a high number of cats (seven to 30 cats). During regular visits to the farms over a 10month period, the cat population and cat defecation sites (latrines and sites of scattered faeces) on each farm were systematically surveyed. During the last visit, 561 soil samples were collected from defecation sites and random points, and these samples were searched for T. gondii DNA using real-time quantitative PCR. Depending on the farm, T. gondii DNA was detected in 37.7-66.3% of the soil samples. The proportion of contaminated samples at a farm was positively correlated with the rate of new cat latrines replacing former cat latrines, suggesting that inconstancy in use of a latrine by cats affects the distribution of T. gondii in soil. On the farms, known cat defecation sites were significantly more often contaminated than random points, but 25-62.5% of the latter were also found to be contaminated. Lastly, the proportion of positive T. gondii samples in latrines was related to the proximity of the cats' main feeding and resting sites on the farms. This study demonstrates that T. gondii can be widely distributed in farm soil despite the heterogeneous distribution of cat faeces. This supports the hypothesis that farms are hotspot areas for the risk of T. gondii oocyst-induced infection in rural environments.


Subject(s)
Cat Diseases/parasitology , Soil/parasitology , Toxoplasma/isolation & purification , Toxoplasmosis, Animal/transmission , Animals , Cats , Cattle , Chi-Square Distribution , Cluster Analysis , DNA, Protozoan/isolation & purification , Dairying , Defecation , Farms , Feces/parasitology , France , Humans , Logistic Models , Oocysts/isolation & purification , Real-Time Polymerase Chain Reaction/veterinary , Spatial Analysis
8.
Parasitology ; 143(5): 557-67, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26928081

ABSTRACT

The aim of this study was to assess the seroprevalence of the Toxoplasma gondii parasite in pork produced in France, and to determine infection risk factors. An innovative survey was designed based on annual numbers of slaughtered pigs from intensive and outdoor farms in France. A total of 1549 samples of cardiac fluids were collected from pig hearts to determine seroprevalence using a Modified Agglutination Test. Of those, 160 hearts were bio-assayed in mice to isolate live parasites. The overall seroprevalence among fattening pigs was 2·9%. The adjusted seroprevalence in pigs from intensive farms was 3·0%; the highest in sows (13·4%); 2·9% in fattening pigs and 2·6% in piglets. Adjusted seroprevalence in fattening animals from outdoor farms was 6·3%. Strains were isolated from 41 animals and all were genotyped by Restriction Fragment Length Polymorphism as type II. Risk-factor analysis showed that the risk of infection was more than three times higher for outdoor pigs, and that sows' risk was almost five times higher than that of fattening animals. This study provides further evidence of extensive pork infection with T. gondii regardless of breeding systems, indicating that farm conditions are still insufficient to guarantee 'Toxoplasma-free pork'.


Subject(s)
Meat/parasitology , Swine Diseases/epidemiology , Toxoplasmosis, Animal/epidemiology , Age Factors , Animals , Antibodies, Protozoan/blood , Breeding/methods , Cross-Sectional Studies , France/epidemiology , Risk Factors , Seroepidemiologic Studies , Swine , Swine Diseases/parasitology , Toxoplasma/immunology , Toxoplasma/isolation & purification
9.
J Appl Microbiol ; 120(2): 498-508, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26551548

ABSTRACT

AIMS: The objective of this study was to evaluate if freshwater bivalves can be used to detect the presence of Toxoplasma gondii in water bodies. METHODS AND RESULTS: Zebra mussels (Dreissena polymorpha) were caged for 1 month upstream and downstream of the discharge points of wastewater treatment plants (WWTPs). Physiological status was assessed to assure good health of bivalves during transplantation. The presence of T. gondii was investigated in mussel tissues by qPCR. In autumn, T. gondii was detected in mussels caged downstream of the discharge points of two WWTPs. In spring, it was detected upstream of one WWTP. CONCLUSIONS: For the first time, T. gondii DNA has been shown in a continental mollusc in environmental conditions. This highlights the interest of an active approach that could be applied independently of the presence or accessibility of autochthonous populations, and underlines the presence of T. gondii in natural waters under pressure of WWTP discharge at a certain time of the year. SIGNIFICANCE AND IMPACT OF THE STUDY: This study shows that transplanted zebra mussels could be used as biosamplers to reveal contamination of freshwater systems by T. gondii.


Subject(s)
Dreissena/parasitology , Fresh Water/parasitology , Toxoplasma/isolation & purification , Animals , Seasons , Toxoplasma/classification , Toxoplasma/genetics , Water Pollution/analysis
10.
Environ Sci Pollut Res Int ; 22(18): 13693-701, 2015 Sep.
Article in English | MEDLINE | ID: mdl-25772876

ABSTRACT

Water quality is a public health concern that calls for relevant biomonitoring programs. Molecular tools such as polymerase chain reaction (PCR) are progressively becoming more sensitive and more specific than conventional techniques to detect pathogens in environmental samples such as water and organisms. The zebra mussel (Dreissena polymorpha) has already been demonstrated to accumulate and concentrate various human waterborne pathogens. In this study, first, a spiking experiment to evaluate detection levels of Toxoplasma gondii DNA in zebra mussel organs using real-time PCR was conducted. Overall, lower DNA levels in the hemolymph, digestive gland, and remaining tissues (gonad and foot) were detected compared to mantle, muscle, and gills. Second, an in vivo experiment with 1000 T. gondii oocysts per mussel and per day for 21 consecutive days, followed by 14 days of depuration time in protozoa-free water was performed. T. gondii DNA was detected in all organs, but greatest concentrations were observed in hemolymph and mantle tissues compared to the others organs at the end of the depuration period. These results suggest that (i) the zebra mussel is a potential new tool for measuring T. gondii concentrations and (ii) real-time PCR is a suitable method for pathogen detection in complex matrices such as tissues.


Subject(s)
Dreissena/parasitology , Toxoplasma/genetics , Animals , DNA, Protozoan/genetics , Host Specificity , Real-Time Polymerase Chain Reaction , Toxoplasma/isolation & purification , Water Quality
11.
J Gynecol Obstet Biol Reprod (Paris) ; 44(9): 848-54, 2015 Nov.
Article in French | MEDLINE | ID: mdl-25604153

ABSTRACT

OBJECTIVE: Evaluate neonatal management and outcome of neonates with either a prenatal or a post-natal diagnosis of EA type III. STUDY DESIGN: Population-based study using data from the French National Register for EA from 2008 to 2010. We compared children with prenatal versus post-natal diagnosis in regards to prenatal, maternal and neonatal characteristics. We define a composite variable of morbidity (anastomotic esophageal leaks, recurrent fistula, stenosis) and mortality at 1 year. RESULTS: Four hundred and eight live births with EA type III were recorded with a prenatal diagnosis rate of 18.1%. Transfer after birth was lower in prenatal subset (32.4% versus 81.5%, P<0.001). Delay between birth and first intervention was not significantly different. Defect size (2cm vs 1.4cm, P<0.001), gastrostomy (21.6% versus 8.7%, P<0.001) and length in neonatal unit care were higher in prenatal subset (47.9 days versus 33.6 days, P<0.001). The composite variables were higher in prenatal diagnosis subset (38.7% vs 26.1%, P=0.044). CONCLUSION: Despite the excellent survival rate of EA, cases with antenatal detection have a higher morbidity related to the EA type (longer gap). Even if it does not modify neonatal management and 1-year outcome, prenatal diagnosis allows antenatal parental counseling and avoids post-natal transfer.


Subject(s)
Esophageal Atresia/diagnosis , Esophageal Atresia/therapy , Prenatal Diagnosis , Age Factors , Esophageal Atresia/classification , Female , Humans , Infant, Newborn , Pregnancy , Prospective Studies , Treatment Outcome
12.
Epidemiol Infect ; 143(3): 586-99, 2015 Feb.
Article in English | MEDLINE | ID: mdl-24838220

ABSTRACT

Leptospira interrogans, hantaviruses (particularly Seoul virus), hepatitis E virus (HEV), and Toxoplasma gondii are rat-associated zoonoses that are responsible for human morbidity and mortality worldwide. This study aimed to describe the infection patterns of these four pathogens in wild rats (Rattus norvegicus) across socioeconomic levels in neighbourhoods in Lyon, France. The infection or exposure status was determined using polymerase chain reaction or serology for 178 wild rats captured in 23 locations; additionally, confirmatory culture or mouse inoculation was performed. Multivariate logistic regression analyses were used to investigate whether morphological and socioeconomic data could predict the infection status of the rats. This study revealed that the rat colony's age structure may influence the prevalence of L. interrogans, hantavirus, and HEV. In addition, areas with high human population densities and low incomes may be associated with a greater number of infected rats and an increased risk of disease transmission.


Subject(s)
Hepatitis E virus/isolation & purification , Leptospira interrogans/isolation & purification , Orthohantavirus/isolation & purification , Rodent Diseases/epidemiology , Toxoplasma/isolation & purification , Zoonoses/epidemiology , Animals , Data Collection , Female , France/epidemiology , Humans , Male , Polymerase Chain Reaction , Population Density , Rats , Rodent Diseases/microbiology , Rodent Diseases/parasitology , Rodent Diseases/virology , Serologic Tests , Socioeconomic Factors , Zoonoses/microbiology , Zoonoses/parasitology , Zoonoses/virology
13.
Rev Sci Instrum ; 85(11): 11D620, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25430196

ABSTRACT

Commissariat à l'Énergie Atomique et aux Énergies Alternatives has developed the ARGOS X-ray framing camera to perform two-dimensional, high-timing resolution imaging of an imploding target on the French high-power laser facility Laser MegaJoule. The main features of this camera are: a microchannel plate gated X-ray detector, a spring-loaded CCD camera that maintains proximity focus in any orientation, and electronics packages that provide remotely-selectable high-voltages to modify the exposure-time of the camera. These components are integrated into an "air-box" that protects them from the harsh environmental conditions. A miniaturized X-ray generator is also part of the device for in situ self-testing purposes.

14.
Environ Geochem Health ; 36(5): 995-1014, 2014 Oct.
Article in English | MEDLINE | ID: mdl-24737418

ABSTRACT

In order to calculate budgets of particulate matter and sediment-bound contaminants leaving the continental shelf of the Gulf of Lion (GoL), settling particles were collected in March 2011 during a major storm, using sediment traps. The collecting devices were deployed in the Cap de Creus submarine canyon, which represents the main export route. Particulate matter samples were analyzed to obtain mass fluxes and contents in organic carbon, Al, Cr, Co, Ni, Cu, Zn, Cd, Pb and La, Nd and Sm. The natural or anthropogenic origin of trace metals was assessed using enrichment factors (EFs). Results are that Zn, Cu and Pb appeared to be of anthropogenic origin, whereas Ni, Co and Cr appeared to be strictly natural. The anthropogenic contribution of all elements (except Cd) was refined by acid-leaching (HCl 1 N) techniques, confirming that Zn, Cu and Pb are the elements that are the most enriched. However, although those elements are highly labile (59-77%), they do not reflect severe enrichment (EFs <4). Most particles originate from the Rhone River. This has been confirmed by two different tracing procedures using rare earth elements ratios and concentrations of acid-leaching residual trace metals. Our results hence indicate that even in this western extremity of the GoL, storm events mainly export Rhone-derived particles via the Cap de Creus submarine canyons to the deep-sea environments. This export of material is significant as it represents about a third of the annual PTM input from the Rhone River.


Subject(s)
Environmental Monitoring , Metals/analysis , Particulate Matter/analysis , Water Pollutants, Chemical/analysis , Weather , Mediterranean Sea , Rivers , Water Pollution/statistics & numerical data
15.
Gene Ther ; 21(2): 168-74, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24285217

ABSTRACT

Adenoviral (AdV) and Adenovirus-associated viral (AAV) vectors both are used for in vivo gene therapy of inherited liver disorders, such as Crigler-Najjar syndrome type 1. In a relevant animal model, the Gunn rat, both vectors efficiently correct the severe hyperbilirubinemia characteristic of this liver disorder. Although the clinical use of AAV is more advanced, as demonstrated by the successful phase 1 trial in hemophilia B patients, because of its large cloning capacity AdV remains an attractive option. A direct comparison of the efficacy of these two vectors in the liver in a relevant disease model has not been reported. Aim of this study was to compare the efficiency of clinically applicable doses of both vectors in the Gunn rat. AdV or scAAV (self-complimentary AAV) ferrying identical liver-specific expression cassettes of the therapeutic gene, UGT1A1, were injected into the tail vein. As the titration methods of these two vectors are very different, a comparison based on vector titers is not valid. Therefore, their efficacy was compared by determining the amount of vector genomes delivered to the liver required for therapeutic correction of serum bilirubin. Like AAV, the liver-specific first-generation AdV also provided sustained correction in this relevant disease model. UGT1A1 mRNA expression provided per genome was comparable for both vectors. Flanking the expression cassette in AdV with AAV-ITRs (inverted terminal repeats), increased UGT1A1 mRNA expression eightfold which resulted in a significant improvement of efficacy. Compared with AAV, less AdV genomes were needed for complete correction of hyperbilirubinemia.


Subject(s)
Adenoviridae/genetics , Dependovirus/genetics , Genetic Vectors/adverse effects , Glucuronosyltransferase/genetics , Liver/metabolism , Liver/virology , Animals , Bilirubin/metabolism , Crigler-Najjar Syndrome/genetics , Crigler-Najjar Syndrome/therapy , Disease Models, Animal , Gene Transfer Techniques , Genetic Therapy , Genetic Vectors/administration & dosage , Glucuronosyltransferase/metabolism , HEK293 Cells , Humans , Liver/pathology , Male , RNA, Messenger/genetics , Rats , Rats, Gunn
16.
Water Res ; 48: 148-55, 2014 Jan 01.
Article in English | MEDLINE | ID: mdl-24112626

ABSTRACT

Cryptosporidium parvum, Giardia duodenalis and Toxoplasma gondii are ubiquitous pathogens, which waterborne transmission has been largely demonstrated. Since they can be found in various watercourses, interactions with aquatic organisms are possible. Protozoan detection for watercourses biomonitoring is currently based on large water filtration. The zebra mussel, Dreissena polymorpha, is a choice biological model in ecotoxicological studies which are already in use to detect chemical contaminations in watercourses. In the present study, the zebra mussel was tested as a new tool for detecting water contamination by protozoa. In vivo exposures were conducted in laboratory experiments. Zebra mussel was exposed to various protozoan concentrations for one week. Detection of protozoa was realized by Taqman real time qPCR. Our experiments evidenced C. parvum, G. duodenalis and T. gondii oocyst bioaccumulation by mussels proportionally to ambient contamination, and significant T. gondii prevalence was observed in muscle tissue. To our knowledge, this is the first study that demonstrates T. gondii oocyst accumulation by zebra mussel. The results from this study highlight the capacity of zebra mussels to reveal ambient biological contamination, and thus to be used as a new effective tool in sanitary biomonitoring of water bodies.


Subject(s)
Bivalvia/parasitology , Cryptosporidium parvum/isolation & purification , Environmental Monitoring , Giardia lamblia/isolation & purification , Toxoplasma/isolation & purification , Animals , Real-Time Polymerase Chain Reaction
17.
Sci Total Environ ; 463-464: 91-101, 2013 Oct 01.
Article in English | MEDLINE | ID: mdl-23792251

ABSTRACT

For centuries, many Mediterranean catchments were covered with vineyards in which copper was widely applied to protect grapevines against fungus. In the Mediterranean-type flow regime, brief and intense flood events increase the stream water discharge by up to 10 times and cause soil leaching and storm runoff. Because vineyards are primarily cultivated on steep slopes, high Cu fluxes are discharged by surface water runoff into the rivers. The purpose of this work was to investigate the riverine behavior and transport of anthropogenic Cu by coupling a sequential chemical extraction (SCE) procedure, used to determine Cu partitioning between residual and non-residual fractions, with δ(65)Cu isotopic measurements in each fraction. In the Baillaury catchment, France, we sampled soils (cultivated and abandoned), river bed sediments (BS), suspended particulate matter (SPM), and river water during the flash flood event of February 2009. Copper partitioning using SCE show that most of Cu in abandoned vineyard soil was in the residual phase (>60%) whereas in cultivated soil, BS and SPM, Cu was mostly (>25%) in non-residual fractions, mainly adsorbed onto iron oxide fractions. A small fraction of Cu was associated with organic matter (5 to 10%). Calculated enrichment factors (EF) are higher than 2 and the anthropogenic contribution was estimated between 50 to 85%. Values for δ(65)Cu in bulk samples were similar to bedrock therefore; δ(65)Cu on SCE fractions of superficial soils and SPM allowed for discrimination between Cu origin and distribution. Copper in residual fractions was of natural mineral origin (δ(65)Cu close to local bedrock, +0.07‰). Copper in water soluble fraction of SPM (δ(65)Cu=+0.26‰) was similar to dissolved river Cu (δ(65)Cu=+0.31‰). Copper from fungicide treatment (δ(65)Cu=-0.35‰) was bound to organic matter (δ(65)Cu=-0.20‰) without or with slight isotopic fractioning. A preferential adsorption of (65)Cu onto iron oxides (δ(65)Cu=+0.5‰) is shown.


Subject(s)
Copper/analysis , Fungicides, Industrial/analysis , Vitis , Agriculture/methods , France , Isotopes/analysis , Soil/chemistry
18.
J Plast Reconstr Aesthet Surg ; 66(12): e373-5, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23721627

ABSTRACT

Giant omphalocele is associated to morbidity and mortality because of the strain the reintegrated herniated mass places on the hemodynamic equilibrium and breathing functions of affected infants. Currently, care management consists in a reintegration in one time or progressive reintegration. We report here a multicenter retrospective study about alternative management by VAC® therapy for giant omphaloceles. The study included three patients (1 girl, 2 boys) presenting with giant omphaloceles, born at full term in three different University Hospitals (prenatal diagnosis, normal karyotype). VAC® therapy was implemented at different times according to the cases (at Day 11, Month 1 and Month 5 after birth). The initial pressure applied was -10 mmHg progressively increased to -50 mmHg. A middle size VAC GranuFoam Silver® Dressing was used in all cases. Wound healing occurred at Month 4 for the first case, Month 6 and Month 8 for the other two. VAC® therapy is a good alternative for the care management of giant omphaloceles with more advantages especially when using prosthetic material. We also aimed at refining the most adapted indications in these specific situations, and finally we envisioned a harmonization of care for these children.


Subject(s)
Negative-Pressure Wound Therapy , Female , Hernia, Umbilical , Humans , Infant, Newborn , Male , Negative-Pressure Wound Therapy/methods , Retrospective Studies , Wound Healing
19.
Gene Ther ; 20(7): 779-84, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23364314

ABSTRACT

Delivery of recombinant adeno-associated virus (rAAV) vectors to the newborn liver is followed by a rapid loss of episomal vector copies because of hepatocyte proliferation. In selected hepatocytes, integration of rAAV genomes can lead to a sustained expression of the transgene. The safety of in vivo gene therapy with single-stranded AAV vectors has been questioned in a study reporting a high incidence of hepatocellular carcinoma, associated with provirus integration events in mice that receive an single-stranded AAV injection at birth. To investigate the tumour-initiating potential of the newly established self-complementary AAV (scAAV) vectors in the liver, groups of newborn rats received intravenous injection of a scAAV vector encoding the green fluorescent protein (GFP), or were injected with phosphate-buffered saline (PBS) or diethylnitrosamine (DEN), a well-known liver tumour initiator. The rats were fed on a diet containing 2-acetylaminofluorene, a potent liver tumour-promoting agent to accelerate the carcinogenic process. After 2 months, the animals were killed and their livers analysed. Preneoplastic nodules were identified by glutathion S-transferase-p (GSTp) staining, and GFP expression was detected by immunohistochemistry. Vector genome integration events were analysed. The numbers of GSTp-positive foci were comparable in the PBS and the scAAV-GFP groups and significantly higher in the DEN group. The proportion of GSTp-positive foci that also expressed GFP was low and in the range expected for random occurrence. No specific integration hot spots were detected by linear amplification-mediated-PCR in transduced liver. In conclusion, scAAV transduction of newborn rat liver does not trigger preneoplastic lesions suggesting an absence of liver tumourigenesis.


Subject(s)
Dependovirus/genetics , Genetic Therapy/adverse effects , Genetic Vectors , Hepatocytes/pathology , Liver/pathology , Animals , Green Fluorescent Proteins , Hepatocytes/virology , Liver/metabolism , Liver/virology , Mice , Neoplasms/genetics , Neoplasms/pathology , Neoplasms/virology , Rats , Transduction, Genetic
20.
Environ Sci Pollut Res Int ; 20(2): 778-89, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23001759

ABSTRACT

Toxoplasma gondii, Cryptosporidium parvum, and Giardia duodenalis are human waterborne protozoa. These worldwide parasites had been detected in various watercourses as recreational, surface, drinking, river, and seawater. As of today, water protozoa detection was based on large water filtration and on sample concentration. Another tool like aquatic invertebrate parasitism could be used for sanitary and environmental biomonitoring. In fact, organisms like filter feeders could already filtrate and concentrate protozoa directly in their tissues in proportion to ambient concentration. So molluscan shellfish can be used as a bioindicator of protozoa contamination level in a site since they were sedentary. Nevertheless, only a few researches had focused on nonspecific parasitism like protozoa infection on aquatic invertebrates. Objectives of this review are twofold: Firstly, an overview of protozoa in worldwide water was presented. Secondly, current knowledge of protozoa parasitism on aquatic invertebrates was detailed and the lack of data of their biological impact was pointed out.


Subject(s)
Environmental Monitoring/methods , Invertebrates/parasitology , Water/parasitology , Animals , Aquatic Organisms/parasitology , Cryptosporidium/physiology , Giardia/pathogenicity , Giardia/physiology , Groundwater/parasitology , Shellfish/parasitology , Toxoplasma/pathogenicity , Toxoplasma/physiology
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