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1.
Sci Total Environ ; 915: 170144, 2024 Mar 10.
Article de Anglais | MEDLINE | ID: mdl-38242468

RÉSUMÉ

Streams are susceptible to pesticide pollutants which are transported outside of the intended area of application from surrounding agricultural fields. It is essential to monitor the occurrence and levels of pesticides in aquatic ecosystems to comprehend their effects on the aquatic environment. The common sampling strategy used for monitoring pesticides in stream ecosystems is through the collection and analysis of grab water samples. However, grab water sampling may not effectively monitor pesticides due to its limited ability to capture temporal and spatial variability, potentially missing fluctuations and uneven distribution of pesticides in aquatic environments. Monitoring using periphyton and sediment sampling may offer a more comprehensive approach by accounting for accumulative processes and temporal variations. Periphyton are a collective of microorganisms that grow on hard surfaces in aquatic ecosystems. They are responsive to chemical and biological changes in the environment, and therefore have the potential to act as a cost-effective, integrated sampling tool to monitor pesticide exposures in aquatic ecosystems. The objective of this study was to assess pesticides detected through periphyton, suspended sediment, and conventional grab water sampling methods and identify the matrix that offers a more comprehensive characterization of a stream's pesticide exposure profile. Ten streams across Southern Ontario were sampled in 2021 and 2022. At each stream site, water, sediment and periphyton, colonizing both artificial and natural substrates, were collected and analyzed for the presence of ~500 pesticides. Each of the three matrices detected distinctive pesticide exposure profiles. The frequency of detection in periphyton, sediment and water matrices were related to pesticides' log Kow and log Koc (P < 0.05). In addition, periphyton bioconcentrated 22 pesticides above levels observed in the ambient water. The bioconcentration factors of pesticides in periphyton can be predicted from their log Kow (simple linear regressions, P < 0.05). The results demonstrate that sediment and periphyton accumulate pesticides in stream environments. This highlights the importance of monitoring pesticide exposure using these matrices to ensure a complete and comprehensive characterization of exposure in stream ecosystems.


Sujet(s)
Périphyton , Pesticides , Polluants chimiques de l'eau , Pesticides/analyse , Écosystème , Rivières/composition chimique , Polluants chimiques de l'eau/analyse , Eau/analyse , Sédiments géologiques , Surveillance de l'environnement/méthodes
2.
Am J Gastroenterol ; 118(5): 905-908, 2023 05 01.
Article de Anglais | MEDLINE | ID: mdl-36689730

RÉSUMÉ

INTRODUCTION: This study evaluates the potential association of pentosan polysulfate (PPS) with inflammatory bowel disease (IBD) or dysplasia. METHODS: We searched electronic medical records to identify patients with IBD using PPS. RESULTS: Ten of 30 identified patients (33.3%) had colonic dysplasia. Six of them (60%) underwent colectomy for endoscopically unresectable dysplasia. Three (10%) discontinued PPS, each with an apparent benefit. DISCUSSION: Patients with IBD at 2 institutions who had taken PPS had high rates of colonic dysplasia leading to surgery. Patients who stopped PPS showed improvement in their colitis. PPS may play a causal role in the development of colitis and dysplasia.


Sujet(s)
Colite , Maladies inflammatoires intestinales , Humains , Pentosane polysulfate/effets indésirables , Maladies inflammatoires intestinales/traitement médicamenteux
3.
Pediatr Blood Cancer ; 69(10): e29773, 2022 10.
Article de Anglais | MEDLINE | ID: mdl-35615775

RÉSUMÉ

BACKGROUND: Children develop symptomatic coronavirus disease 2019 (COVID-19) more rarely than adults upon infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Pediatric oncology and hematology patients may be at increased risk of severe COVID-19 due to their underlying disease or treatment. We investigated COVID-19 and seroprevalence of anti-SARS-CoV-2 antibodies, respectively, in a Swedish cohort of pediatric oncology and hematology patients. PROCEDURE: Patients (n = 136) were recruited between June 2020 and September 2021 at Uppsala University Children's Hospital, Sweden. Up to six consecutive blood samples per patient were analyzed for wild-type anti-S1 IgM and IgG antibodies (including after vaccination, n = 4). Clinical data on COVID-19 (including polymerase chain reaction [PCR] test results) were collected from electronic medical records. A questionnaire was completed at recruitment. RESULTS: A cumulative seroprevalence (IgM and IgG) of 33% (45/136 patients, 95% confidence interval: 25%-41%) was observed in this patient cohort, of whom 66% (90/136 patients) were under severe immunosuppressive treatment during the study period. Increasing patient age (p = .037) and PCR test results (p < .002) were associated with seropositivity in nonvaccinated cases. Most seropositive, nonvaccinated cases (32/43, 74%) were never PCR-verified for SARS-CoV-2 infection. Of the 13 patients with PCR-verified infection, nine (69%) reported mild disease. A majority (63%) reported continued school attendance during the pandemic. CONCLUSIONS: Swedish pediatric oncology and hematology patients developed antibodies against SARS-CoV-2, despite their diagnosis and/or treatment, and the observed seroprevalence was similar to that in national pediatric outpatients. PCR-verified cases underestimate the true incidence of COVID-19 in this patient cohort.


Sujet(s)
COVID-19 , Hématologie , Tumeurs , Adulte , Anticorps antiviraux , COVID-19/épidémiologie , Enfant , Humains , Immunoglobuline G , Immunoglobuline M , Tumeurs/épidémiologie , SARS-CoV-2 , Études séroépidémiologiques , Suède/épidémiologie
4.
J Neuroeng Rehabil ; 19(1): 31, 2022 Mar 21.
Article de Anglais | MEDLINE | ID: mdl-35313892

RÉSUMÉ

Electrical stimulation has shown to be a promising approach for promoting osseointegration in bone anchoring implants, where osseointegration defines the biological bonding between the implant surface and bone tissue. Bone-anchored implants are used in the rehabilitation of hearing and limb loss, and extensively in edentulous patients. Inadequate osseointegration is one of the major factors of implant failure that could be prevented by accelerating or enhancing the osseointegration process by artificial means. In this article, we reviewed the efforts to enhance the biofunctionality at the bone-implant interface with electrical stimulation using the implant as an electrode. We reviewed articles describing different electrode configurations, power sources, and waveform-dependent stimulation parameters tested in various in vitro and in vivo models. In total 55 English-language and peer-reviewed publications were identified until April 2020 using PubMed, Google Scholar, and the Chalmers University of Technology Library discovery system using the keywords: osseointegration, electrical stimulation, direct current and titanium implant. Thirteen of those publications were within the scope of this review. We reviewed and compared studies from the last 45 years and found nonuniform protocols with disparities in cell type and animal model, implant location, experimental timeline, implant material, evaluation assays, and type of electrical stimulation. The reporting of stimulation parameters was also found to be inconsistent and incomplete throughout the literature. Studies using in vitro models showed that osteoblasts were sensitive to the magnitude of the electric field and duration of exposure, and such variables similarly affected bone quantity around implants in in vivo investigations. Most studies showed benefits of electrical stimulation in the underlying processes leading to osseointegration, and therefore we found the idea of promoting osseointegration by using electric fields to be supported by the available evidence. However, such an effect has not been demonstrated conclusively nor optimally in humans. We found that optimal stimulation parameters have not been thoroughly investigated and this remains an important step towards the clinical translation of this concept. In addition, there is a need for reporting standards to enable meta-analysis for evidence-based treatments.


Sujet(s)
Interface os-implant , Ostéo-intégration , Animaux , Stimulation électrique , Humains , Ostéo-intégration/physiologie , Prothèses et implants , Propriétés de surface , Titane
5.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 4600-4604, 2021 11.
Article de Anglais | MEDLINE | ID: mdl-34891537

RÉSUMÉ

In research on lower limb prostheses, safety during testing and training is paramount. Lower limb prosthesis users risk unintentional loss of balance that can result in injury, fear of falling, and overall decreased confidence in their prosthetic leg. Here, we present a protocol for managing the risks during evaluation of active prosthetic legs with modifiable control systems. We propose graded safety levels, each of which must be achieved before advancing to the next one, from laboratory bench testing to independent ambulation in real-world environments.


Sujet(s)
Chutes accidentelles , Membres artificiels , Chutes accidentelles/prévention et contrôle , Humains , Membre inférieur , Équilibre postural , Gestion du risque
7.
Environ Sci Pollut Res Int ; 28(16): 20883-20893, 2021 Apr.
Article de Anglais | MEDLINE | ID: mdl-33405173

RÉSUMÉ

Firefighting water additives are used to increase the rate at which fires can be extinguished. The majority of ecotoxicological research has focused on firefighting formulations containing perfluorinated compounds as additives, due to the persistence and bioaccumulative nature of the perfluorinated constituents. A number of relatively new additives have come on the market to replace the products containing perfluorinated compounds. The potential effect of these new additives on the environment has been largely unstudied. This study investigated the toxicity of six firefighting water additives: Eco-Gel™, ThermoGel 200L™, FireAde™, Fire-Brake™, Novacool Foam™, and F-500™ to terrestrial biota. Terrestrial organisms could be exposed to firefighting water additives through leaching into soil and/or runoff following a firefighting event or through direct aerial application during a forest fire. Toxicity to three plant species was assessed through seedling germination and emergence tests: Fagopyrum esculentum (buckwheat), Raphanus raphanistrum subsp. sativus (radish), and Rudbeckia hirta (black-eyed Susan). The effects of firefighting water additives on three soil invertebrates, the collembolan Folsomia candida, the earthworms Eisenia andrei, and Dendrodrilus rubidus, were also investigated using static acute tests to estimate EC50/LC50s. The concentration that resulted in a 50% reduction in survival (LC50) for the acute toxicity tests conducted with F. candida ranged from 3 (Eco-Gel) to 0.175% (Novacool) by volume. Comparatively, the acute toxicity of two firefighting water additives to D. rubidus could not be determined, as a 50% reduction in survival was not observed. A number of firefighting water additives were found to pose a hazard to terrestrial organisms based on a worst-case exposure scenario of direct application at the greatest recommended application rate for a class A fire (e.g., wood, paper). The firefighting water additive F-500 was found to pose a hazard (HQ ≥ 1) for all species tested, except for the acute test conducted with D. rubidus. Comparatively, Eco-Gel posed a hazard for only the acute and chronic tests with F. candida. This study represents the first comparative deterministic risk assessment of firefighting water additives to terrestrial ecosystems.


Sujet(s)
Arthropodes , Oligochaeta , Polluants du sol , Animaux , Écosystème , Appréciation des risques , Sol , Polluants du sol/analyse , Eau
8.
Front Immunol ; 9: 301, 2018.
Article de Anglais | MEDLINE | ID: mdl-29535712

RÉSUMÉ

Systems biology approaches have recently provided new insights into the mechanisms of action of human vaccines and adjuvants. Here, we investigated early transcriptional signatures induced in whole blood of healthy subjects following vaccination with a recombinant HIV-1 envelope glycoprotein subunit CN54gp140 adjuvanted with the TLR4 agonist glucopyranosyl lipid adjuvant-aqueous formulation (GLA-AF) and correlated signatures to CN54gp140-specific serum antibody responses. Fourteen healthy volunteers aged 18-45 years were immunized intramuscularly three times at 1-month intervals and whole blood samples were collected at baseline, 6 h, and 1, 3, and 7 days post first immunization. Subtle changes in the transcriptomic profiles were observed following immunization, ranging from over 300 differentially expressed genes (DEGs) at day 1 to nearly 100 DEGs at day 7 following immunization. Functional pathway analysis revealed blood transcription modules (BTMs) related to general cell cycle activation, and innate immune cell activation at early time points, as well as BTMs related to T cells and B cell activation at the later time points post-immunization. Diverse CN54gp140-specific serum antibody responses of the subjects enabled their categorization into high or low responders, at early (<1 month) and late (up to 6 months) time points post vaccination. BTM analyses revealed repression of modules enriched in NK cells, and the mitochondrial electron chain, in individuals with high or sustained antigen-specific antibody responses. However, low responders showed an enhancement of BTMs associated with enrichment in myeloid cells and monocytes as well as integrin cell surface interactions. Flow cytometry analysis of peripheral blood mononuclear cells obtained from the subjects revealed an enhanced frequency of CD56dim NK cells in the majority of vaccines 14 days after vaccination as compared with the baseline. These results emphasize the utility of a systems biology approach to enhance our understanding on the mechanisms of action of TLR4 adjuvanted human vaccines.


Sujet(s)
Vaccins contre le SIDA/pharmacologie , Adjuvants immunologiques/pharmacologie , Transcriptome/effets des médicaments et des substances chimiques , Vaccins contre le SIDA/immunologie , Adolescent , Adulte , Femelle , Anticorps anti-VIH/sang , Infections à VIH/immunologie , Infections à VIH/prévention et contrôle , VIH-1 (Virus de l'Immunodéficience Humaine de type 1) , Humains , Activation des lymphocytes/effets des médicaments et des substances chimiques , Mâle , Adulte d'âge moyen , Protéines recombinantes/immunologie , Protéines recombinantes/pharmacologie , Biologie des systèmes/méthodes , Récepteur de type Toll-4/agonistes , Jeune adulte , Produits du gène env du virus de l'immunodéficience humaine/immunologie , Produits du gène env du virus de l'immunodéficience humaine/pharmacologie
9.
Sci Rep ; 6: 39097, 2016 12 13.
Article de Anglais | MEDLINE | ID: mdl-27958370

RÉSUMÉ

A better understanding of the mechanisms of action of human adjuvants could inform a rational development of next generation vaccines for human use. Here, we exploited a genome wide transcriptomics analysis combined with a systems biology approach to determine the molecular signatures induced by four clinically tested vaccine adjuvants, namely CAF01, IC31, GLA-SE and Alum in mice. We report signature molecules, pathways, gene modules and networks, which are shared by or otherwise exclusive to these clinical-grade adjuvants in whole blood and draining lymph nodes of mice. Intriguingly, co-expression analysis revealed blood gene modules highly enriched for molecules with documented roles in T follicular helper (TFH) and germinal center (GC) responses. We could show that all adjuvants enhanced, although with different magnitude and kinetics, TFH and GC B cell responses in draining lymph nodes. These results represent, to our knowledge, the first comparative systems analysis of clinically tested vaccine adjuvants that may provide new insights into the mechanisms of action of human adjuvants.


Sujet(s)
Adjuvants immunologiques/administration et posologie , Réseaux de régulation génique/effets des médicaments et des substances chimiques , Centre germinatif/immunologie , Glucosides/administration et posologie , Lipide A/administration et posologie , Oligodésoxyribonucléotides/administration et posologie , Oligopeptides/administration et posologie , Lymphocytes T auxiliaires/immunologie , Immunité acquise , Adjuvants immunologiques/pharmacologie , Animaux , Association médicamenteuse , Analyse de profil d'expression de gènes , Régulation de l'expression des gènes/effets des médicaments et des substances chimiques , Centre germinatif/effets des médicaments et des substances chimiques , Glucosides/pharmacologie , Humains , Lipide A/pharmacologie , Oligodésoxyribonucléotides/pharmacologie , Oligopeptides/pharmacologie , Analyse des systèmes , Biologie des systèmes , Lymphocytes T auxiliaires/effets des médicaments et des substances chimiques , Vaccination
10.
Vaccine ; 32(49): 6614-21, 2014 Nov 20.
Article de Anglais | MEDLINE | ID: mdl-25312275

RÉSUMÉ

Bluetongue virus (BTV) infections in ruminants pose a permanent agricultural threat since new serotypes are constantly emerging in new locations. Clinical disease is mainly observed in sheep, but cattle were unusually affected during an outbreak of BTV seroype 8 (BTV-8) in Europe. We previously developed an experimental vaccine based on recombinant viral protein 2 (VP2) of BTV-8 and non-structural proteins 1 (NS1) and NS2 of BTV-2, mixed with an immunostimulating complex (ISCOM)-matrix adjuvant. We demonstrated that bovine immune responses induced by this vaccine were as good or superior to those induced by a classic commercial inactivated vaccine. In this study, we evaluated the protective efficacy of the experimental vaccine in cattle and, based on the detection of VP7 antibodies, assessed its DIVA compliancy following virus challenge. Two groups of BTV-seronegative calves were subcutaneously immunized twice at a 3-week interval with the subunit vaccine (n=6) or with adjuvant alone (n=6). Following BTV-8 challenge 3 weeks after second immunization, controls developed viremia and fever associated with other mild clinical signs of bluetongue disease, whereas vaccinated animals were clinically and virologically protected. The vaccine-induced protection was likely mediated by high virus-neutralizing antibody titers directed against VP2 and perhaps by cellular responses to NS1 and NS2. T lymphocyte responses were cross-reactive between BTV-2 and BTV-8, suggesting that NS1 and NS2 may provide the basis of an adaptable vaccine that can be varied by using VP2 of different serotypes. The detection of different levels of VP7 antibodies in vaccinated animals and controls after challenge suggested a compliancy between the vaccine and the DIVA companion test. This BTV subunit vaccine is a promising candidate that should be further evaluated and developed to protect against different serotypes.


Sujet(s)
Virus de la langue bleue/immunologie , Fièvre catarrhale du mouton/prévention et contrôle , Vaccins antiviraux/immunologie , Virémie/prévention et contrôle , Adjuvants immunologiques/administration et posologie , Animaux , Anticorps neutralisants/sang , Anticorps antiviraux/sang , Fièvre catarrhale du mouton/immunologie , Fièvre catarrhale du mouton/anatomopathologie , Virus de la langue bleue/classification , Bovins , Cholestérol/administration et posologie , Association médicamenteuse , Femelle , Injections sous-cutanées , Phospholipides/administration et posologie , Saponines/administration et posologie , Sérogroupe , Vaccination/méthodes , Vaccins sous-unitaires/administration et posologie , Vaccins sous-unitaires/immunologie , Protéines virales non structurales/immunologie , Vaccins antiviraux/administration et posologie , Virémie/immunologie
11.
J Neurosci Methods ; 235: 123-9, 2014 Sep 30.
Article de Anglais | MEDLINE | ID: mdl-25004204

RÉSUMÉ

BACKGROUND: Evidence point to vascular dysfunction and hypoperfusion as early abnormalities in Alzheimer's disease (AD); probing their mechanistic bases can lead to new therapeutic approaches. We tested the hypotheses that ß-amyloid peptide induces endothelial dysfunction and oxidative stress in human microvasculature and that response will be similar between peripheral adipose and brain leptomeningeal arterioles. NEW METHOD: Abdominal subcutaneous arterioles from living human subjects (n=17) and cadaver leptomeningeal arterioles (n=6) from rapid autopsy were exposed to Aß1-42 (Aß) for 1-h and dilation response to acetylcholine/papaverine were measured and compared to baseline response. Adipose arteriole reactive oxygen species (ROS) production and nitrotyrosine content were measured. COMPARISON WITH EXISTING METHODS: Methods described allow direct investigation of human microvessel functional response that cannot be replicated by human noninvasive imaging or post-mortem histology. RESULTS: Adipose arterioles exposed to 2 µM Aß showed impaired dilation to acetylcholine that was reversed by antioxidant polyethylene glycol superoxide dismutase (PEG-SOD) (Aß-60.9 ± 6%, control-93.2 ± 1.8%, Aß+PEGSOD-84.7 ± 3.9%, both p<0.05 vs. Aß). Aß caused reduced dilation to papaverine. Aß increased adipose arteriole ROS production and increased arteriole nitrotyrosine content. Leptomeningeal arterioles showed similar impaired response to acetylcholine when exposed to Aß (43.0 ± 6.2% versus 81.1 ± 5.7% control, p<0.05). CONCLUSION: Aß exposure induced adipose arteriole endothelial and non-endothelial dysfunction and oxidative stress that were reversed by antioxidant treatment. Aß-induced endothelial dysfunction was similar between peripheral adipose and leptomeningeal arterioles. Ex vivo living adipose and cadaver leptomeningeal arterioles are viable, novel and practical human tissue models to study Alzheimer's vascular pathophysiology.


Sujet(s)
Tissu adipeux/vascularisation , Peptides bêta-amyloïdes , Artérioles/physiopathologie , Cellules endothéliales/physiologie , Méninges/vascularisation , Fragments peptidiques , Abdomen/vascularisation , Acétylcholine/pharmacologie , Sujet âgé , Sujet âgé de 80 ans ou plus , Maladie d'Alzheimer/physiopathologie , Femelle , Humains , Mâle , Adulte d'âge moyen , Stress oxydatif/physiologie , Papavérine/pharmacologie , Espèces réactives de l'oxygène/métabolisme , Tyrosine/analogues et dérivés , Tyrosine/métabolisme , Vasodilatateurs/pharmacologie
12.
Clin Vaccine Immunol ; 21(3): 443-52, 2014 Mar.
Article de Anglais | MEDLINE | ID: mdl-24451327

RÉSUMÉ

Bluetongue virus (BTV) causes bluetongue disease, a vector-borne disease of ruminants. The recent northerly spread of BTV serotype 8 in Europe resulted in outbreaks characterized by clinical signs in cattle, including unusual teratogenic effects. Vaccination has been shown to be crucial for controlling the spread of vector-borne diseases such as BTV. With the aim of developing a novel subunit vaccine targeting BTV-8 that allows differentiation of infected from vaccinated animals, five His-tagged recombinant proteins, VP2 and VP5 of BTV-8 and NS1, NS2, and NS3 of BTV-2, were expressed in baculovirus or Escherichia coli expression systems for further study. Optimized purification protocols were determined for VP2, NS1, NS2, and NS3, which remained stable for detection for at least 560 to 610 days of storage at +4°C or -80°C, and Western blotting using sera from vaccinated or experimentally infected cattle indicated that VP2 and NS2 were recognized by BTV-specific antibodies. To characterize murine immune responses to the four proteins, mice were subcutaneously immunized twice at a 4-week interval with one of three protein combinations plus immunostimulating complex ISCOM-Matrix adjuvant or with ISCOM-Matrix alone (n = 6 per group). Significantly higher serum IgG antibody titers specific for VP2 and NS2 were detected in immunized mice than were detected in controls. VP2, NS1, and NS2 but not NS3 induced specific lymphocyte proliferative responses upon restimulation of spleen cells from immunized mice. The data suggest that these recombinant purified proteins, VP2, NS1, and NS2, could be an important part of a novel vaccine design against BTV-8.


Sujet(s)
Antigènes viraux/immunologie , Antigènes viraux/isolement et purification , Virus de la langue bleue/immunologie , Protéines virales/immunologie , Protéines virales/isolement et purification , Vaccins antiviraux/isolement et purification , Adjuvants immunologiques/administration et posologie , Animaux , Anticorps antiviraux/sang , Antigènes viraux/composition chimique , Baculoviridae/génétique , Bovins , Prolifération cellulaire , Cholestérol/administration et posologie , Association médicamenteuse , Escherichia coli/génétique , Expression des gènes , Immunoglobuline G/sang , Injections sous-cutanées , Lymphocytes/immunologie , Souris , Phospholipides/administration et posologie , Stabilité protéique , Saponines/administration et posologie , Vaccination/méthodes , Vaccins marqueurs/composition chimique , Vaccins marqueurs/immunologie , Vaccins marqueurs/isolement et purification , Vaccins sous-unitaires/composition chimique , Vaccins sous-unitaires/immunologie , Vaccins sous-unitaires/isolement et purification , Vaccins synthétiques/composition chimique , Vaccins synthétiques/immunologie , Vaccins synthétiques/isolement et purification , Protéines virales/composition chimique , Vaccins antiviraux/composition chimique , Vaccins antiviraux/immunologie
13.
Clin Vaccine Immunol ; 20(8): 1115-22, 2013 Aug.
Article de Anglais | MEDLINE | ID: mdl-23720365

RÉSUMÉ

Bluetongue virus (BTV), the causative agent of bluetongue in ruminants, is an emerging virus in northern Europe. The 2006 outbreak of BTV serotype 8 (BTV-8) in Europe was marked by an unusual teratogenic effect and a high frequency of clinical signs in cattle. Conventional control strategies targeting small ruminants were therefore extended to include cattle. Since cattle were not routinely vaccinated before 2006, the immune responses to BTV have not been studied extensively in this species. With the aims of developing a subunit vaccine against BTV-8 for differentiation between infected and vaccinated animals based on viral protein 7 (VP7) antibody detection and of improving the current understanding of the immunogenicity of BTV proteins in cattle, the immune responses induced by recombinant VP2 (BTV-8) and nonstructural protein 1 (NS1) and NS2 (BTV-2) were studied. Cows were immunized twice (with a 3-week interval) with the experimental vaccine, a commercial inactivated vaccine, or a placebo. The two vaccines induced similar neutralizing antibody responses to BTV-8. Furthermore, the antibody responses detected against VP2, NS1, and NS2 were strongest in the animals immunized with the experimental vaccine, and for the first time, a serotype cross-reactive antibody response to NS2 was shown in cattle vaccinated with the commercial vaccine. The two vaccines evoked measurable T cell responses against NS1, thereby supporting a bovine cross-reactive T cell response. Finally, VP7 seroconversion was observed after vaccination with the commercial vaccine, as in natural infections, but not after vaccination with the experimental vaccine, indicating that the experimental vaccine may allow the differentiation of vaccinated animals from infected animals regardless of BTV serotype. The experimental vaccine will be further evaluated during a virulent challenge in a high-containment facility.


Sujet(s)
Antigènes viraux/immunologie , Virus de la langue bleue/immunologie , Fièvre catarrhale du mouton/immunologie , Fièvre catarrhale du mouton/prévention et contrôle , Vaccins marqueurs/immunologie , Vaccins antiviraux/immunologie , Animaux , Anticorps neutralisants/sang , Anticorps antiviraux/sang , Antigènes viraux/administration et posologie , Bovins , Maladies des bovins/immunologie , Maladies des bovins/prévention et contrôle , Lymphocytes T/immunologie , Vaccins marqueurs/administration et posologie , Vaccins sous-unitaires/administration et posologie , Vaccins sous-unitaires/immunologie , Protéines virales/administration et posologie , Protéines virales/immunologie , Vaccins antiviraux/administration et posologie
14.
Vaccine ; 29(47): 8719-30, 2011 Nov 03.
Article de Anglais | MEDLINE | ID: mdl-21864616

RÉSUMÉ

Bovine respiratory syncytial virus (BRSV) is a major cause of bronchiolitis and pneumonia in cattle and causes yearly outbreaks with high morbidity in Europe. Commercial vaccines against this virus needs improvement of efficacy, especially in calves with BRSV-specific maternally derived antibodies (MDA). We previously reported that an experimental BRSV-ISCOM vaccine, but not a commercial vaccine, induced strong clinical and virological protection in calves with MDA, immunized at 7-15 weeks of age. The aim of the present study was to characterize the immune responses, as well as to investigate the efficacy and safety in younger animals, representing the target population for vaccination. Four groups of five 3-8 week old calves with variable levels of BRSV-specific MDA were immunized s.c. twice at a 3 weeks interval with (i) BRSV immunostimulating complexes (BRSV-ISCOMs), (ii) BRSV-protein, (iii) adjuvant, or (iv) PBS. All calves were challenged with virulent BRSV by aerosol 2 weeks later and euthanized on day 6 after infection. The cellular and humoral responses were monitored as well as the clinical signs, the viral excretion and the pathology following challenge. Despite presence of MDA at the time of the immunization, only a minimum of clinical signs were observed in the BRSV-ISCOM group after challenge. In contrast, in all control groups, clinical signs of disease were observed in most of the animals (respiratory rates up to 76min(-1) and rectal temperatures up to 41°C). The clinical protection was associated to a highly significant reduction of virus replication in the upper and lower respiratory tract of calves, rapid systemic and local antibody responses and T helper cell responses dominated by IFNγ production. Animals that did not shed virus detectable by PCR or cell culture following challenge possessed particularly high levels of pulmonary IgA. The protective immunological responses to BRSV proteins and the ability to overcome the inhibiting effect of MDA were dependent on ISCOM borne antigen presentation.


Sujet(s)
Maladies des bovins/prévention et contrôle , Vecteurs de médicaments/administration et posologie , Complexes immunostimulants/administration et posologie , Infections à virus respiratoire syncytial/médecine vétérinaire , Virus respiratoire syncytial bovin/immunologie , Vaccins antiviraux/effets indésirables , Vaccins antiviraux/immunologie , Animaux , Anticorps antiviraux/sang , Bronchiolite/anatomopathologie , Bronchiolite/prévention et contrôle , Bronchiolite/médecine vétérinaire , Bovins , Maladies des bovins/anatomopathologie , Europe , Rappel de vaccin/méthodes , Immunoglobuline A/analyse , Immunoglobuline G/sang , Injections sous-cutanées , Agranulocytes/immunologie , Pneumopathie virale/anatomopathologie , Pneumopathie virale/prévention et contrôle , Pneumopathie virale/médecine vétérinaire , Infections à virus respiratoire syncytial/anatomopathologie , Infections à virus respiratoire syncytial/prévention et contrôle , Appareil respiratoire/immunologie , Appareil respiratoire/anatomopathologie , Appareil respiratoire/virologie , Indice de gravité de la maladie , Vaccination/méthodes , Vaccins antiviraux/administration et posologie
15.
J Adolesc ; 28(4): 523-33, 2005 Aug.
Article de Anglais | MEDLINE | ID: mdl-16022886

RÉSUMÉ

First-year college students were asked to complete alcohol consumption and identity status questionnaires-currently and retrospectively. Trend analyses of the retrospective data and current data revealed somewhat similar inverse linear trends for identity status on absolute annual alcohol consumption. In both cases, identity sophistication was associated with lower levels of consumption. Of the students who reported an increase in consumption from the junior year of high school to the first year of college, those displaying progressive identity development reported a relatively lower increase in consumption than those displaying stable identity status. This difference approached the conventional level of significance. The implications of these findings are explored.


Sujet(s)
Consommation d'alcool/épidémiologie , Concept du soi , Identification sociale , Étudiants/statistiques et données numériques , Universités , Adolescent , Adulte , Femelle , Humains , Mâle , Études rétrospectives
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