Despite a population immunity level estimated at ∼95%, an outbreak of measles responsible for 94 cases occurred in Quebec, Canada. Unlike previous outbreaks in which most unvaccinated children ...belonged to a single community, this outbreak had cases coming from several unrelated networks of unvaccinated persons dispersed in the population. No epidemiological link was found for about one-third of laboratory-confirmed cases. This outbreak demonstrated that minimal changes in the level of aggregation of unvaccinated individuals can lead to sustained transmission in highly vaccinated populations. Mathematical work is needed regarding the level of aggregation of unvaccinated individuals that would jeopardize elimination
The cytolethal distending toxin (CDT) is produced by several Gram-negative pathogenic bacteria. In addition to inflammation, experimental evidences are in favor of a protumoral role of CDT-harboring ...bacteria such as
Escherichia coli
,
Campylobacter jejuni
, or
Helicobacter hepaticus
. CDT may contribute to cell transformation
in vitro
and carcinogenesis in mice models, through the genotoxic action of CdtB catalytic subunit. Here, we investigate the mechanism of action by which CDT leads to genetic instability in human cell lines and colorectal organoids from healthy patients’ biopsies. We demonstrate that CDT holotoxin induces a replicative stress dependent on CdtB. The slowing down of DNA replication occurs mainly in late S phase, resulting in the expression of fragile sites and important chromosomic aberrations. These DNA abnormalities induced after CDT treatment are responsible for anaphase bridge formation in mitosis and interphase DNA bridge between daughter cells in G1 phase. Moreover, CDT-genotoxic potential preferentially affects human cycling cells compared to quiescent cells. Finally, the toxin induces nuclear distension associated to DNA damage in proliferating cells of human colorectal organoids, resulting in decreased growth. Our findings thus identify CDT as a bacterial virulence factor targeting proliferating cells, such as human colorectal progenitors or stem cells, inducing replicative stress and genetic instability transmitted to daughter cells that may therefore contribute to carcinogenesis. As some CDT-carrying bacterial strains were detected in patients with colorectal cancer, targeting these bacteria could be a promising therapeutic strategy.
Please cite this paper as: Van Buynder et al. (2013). Increased reactions to pediatric influenza vaccination following concomitant pneumococcal vaccination Influenza and Other Respiratory Viruses ...7(2) 184–190.
Background Influenza in children causes significant morbidity and hospitalizations and also some mortality particularly in children <5 years of age. Influenza vaccination in children has been shown to be safe and effective, but in 2010 the pediatric influenza vaccination program was suspended in Western Australia after the rate of febrile convulsions observed (9/1000 doses) was 55 times the previously reported rate.
In 2009, over 80% of all children in New Brunswick were vaccinated with an adjuvanted monovalent H1N1 vaccine shown to have very high effectiveness, raising the prospect of potential hyper‐responsiveness because of residual protection. We conducted enhanced post‐marketing surveillance to monitor local and general reactions.
Methods Parents of participating children seen at dedicated vaccination clinics were given influenza vaccine survey kits to record local and general symptoms up to 3 days following receipt of season influenza vaccine.
Results Febrile reactions of ≥38° occurred in <10% of children who received a first dose of seasonal influenza vaccine (n = 660) and severe febrile incidents with fever ≥39° were uncommon. Concurrent administration of other vaccine(s) including conjugated pneumococcal vaccine appeared to increase reactogenicity. No child in the study had a febrile convulsion.
Conclusion Influenza vaccines in children are safe, and this study provides a baseline for rapid assessment studies at the start of a vaccine season. Parents should be aware of increased fevers with concurrent vaccine administration, and antipyretics should be considered.
We conducted a case-control study to describe the clinical and epidemiologic characteristics of an outbreak of pandemic (H1N1) 2009 at a Canadian military cadet training center. We found that asthma ...and obesity confer greater risk for infection. Viral shedding was detected by PCR up to 18 days after symptom onset.
A multi-province outbreak of listeriosis occurred in Canada from June to November 2008. Fifty-seven persons were infected with 1 of 3 similar outbreak strains defined by pulsed-field gel ...electrophoresis, and 24 (42%) individuals died. Forty-one (72%) of 57 individuals were residents of long-term care facilities or hospital inpatients during their exposure period. Descriptive epidemiology, product traceback, and detection of the outbreak strains of Listeria monocytogenes in food samples and the plant environment confirmed delicatessen meat manufactured by one establishment and purchased primarily by institutions was the source of the outbreak. The food safety investigation identified a plant environment conducive to the introduction and proliferation of L. monocytogenes and persistently contaminated with Listeria spp. This outbreak demonstrated the need for improved listeriosis surveillance, strict control of L. monocytogenes in establishments producing ready-to-eat foods, and advice to vulnerable populations and institutions serving these populations regarding which high-risk foods to avoid.
This research is a qualitative case study of graduate certificate programs offered in college counseling in the United States. This study presents historical and current information about eight ...different college counseling certificate programs and seven themes that describe these programs in the context of national college access and college readiness goals. Eight programs were identified at four schools in California, one school in Michigan, one school in Minnesota, and one school in Massachusetts. These certificate programs have a bifurcated history and have existed since 1990. Results of the study revealed: the two major types of college counseling certificate programs, their role in creating private counseling practices, the types of readings in the programs, as well as the variability of the courses, subjects, and instructional faculty. This research fills a gap in the literature, provides recommendations for advancing these certificate programs within the emerging academic discipline of college counseling, and suggests future related research that should be conducted. Overall, this study raises the visibility of this training pathway. Keywords: graduate coursework, college counseling, admission counseling, college access, certificate programs, college readiness.
Le Québec est le théâtre de nombreux glissements de terrain chaque année. Ces glissements de terrain peuvent être une menace pour les vies humaines ainsi que pour les infrastructures comme l'ont ...démontré l'évènement de Saint-Jean-Vianney en 1971 ayant causé la mort de 31 personnes ainsi que celui de Saint-Jude en 2010 ayant causé la mort de quatre personnes. Les glissements de terrain peuvent être influencés par le climat, mais des études récentes démontrent que le lien entre climat et stabilité des pentes est encore flou et méconnu. Une meilleure compréhension entre les évènements climatiques et les glissements de terrain est donc nécessaire. L'objectif de la présente étude est d'évaluer, par modélisation numérique, les conséquences de la variation des précipitations sur l'écoulement de l'eau souterraine et la stabilité d'une pente argileuse située dans le secteur de Saint-Luc-de-Vincennes dans un contexte de changements climatiques. Ces conséquences sont la variation de la recharge en sommet de talus, la variation du niveau d'eau dans la rivière Champlain à la base de la pente ainsi que l'érosion par cette même rivière à la base de la pente. Pour ce faire, une pente du secteur a été modélisée à l'aide des logiciels SEEP/W et SLOPE/W en régimes permanent et transitoire de manière à obtenir des charges hydrauliques semblables à celles observées sur le terrain. Les données de charges hydrauliques sur le terrain ont été mesurées à partir de trois nids de piézomètres contenant chacun quatre piézomètres à différentes profondeurs. Une fois le modèle de base bien calibré, les trois conséquences à l'étude ont pu être évaluées en modifiant les conditions limites et la géométrie du modèle. La variation de la recharge a été évaluée en faisant varier la condition de recharge en sommet de talus et dans la pente, la variation du niveau d'eau dans la rivière a été testée en faisant varier la condition de charge à la base de la pente au niveau de la rivière et l'érosion a été testée via deux géométries d'érosion. Les résultats de cette étude montrent que l'augmentation de la recharge ainsi que l'érosion ont un effet négatif sur la stabilité de la pente, tandis que la variation du niveau d'eau dans la rivière a un effet qui peut être positif et négatif. C'est cette dernière variable qui a d'ailleurs le plus d'effet sur la stabilité de la pente, suivi par l'érosion et la variation de la recharge. De récentes études indiquent que les précipitations et les évènements de précipitation devraient augmenter dans les années à venir dans l'est du Canada tandis que les débits moyens des rivières du sud du Québec devraient augmenter en hiver et diminuer au printemps, en été et à l'automne. Ces changements influenceront les dynamiques de recharge, de variation du niveau d'eau dans les rivières et d'érosion. Il est donc attendu que la stabilité de la pente à l'étude en soit influencée négativement.
Microglia are brain-resident immune cells with a repertoire of functions in the brain. However, the extent of their interactions with the vasculature and potential regulation of vascular physiology ...has been insufficiently explored. Here, we document interactions between ramified CX3CR1
myeloid cell somata and brain capillaries. We confirm that these cells are bona fide microglia by molecular, morphological and ultrastructural approaches. Then, we give a detailed spatio-temporal characterization of these capillary-associated microglia (CAMs) comparing them with parenchymal microglia (PCMs) in their morphological activities including during microglial depletion and repopulation. Molecularly, we identify P2RY12 receptors as a regulator of CAM interactions under the control of released purines from pannexin 1 (PANX1) channels. Furthermore, microglial elimination triggered capillary dilation, blood flow increase, and impaired vasodilation that were recapitulated in P2RY12
and PANX1
mice suggesting purines released through PANX1 channels play important roles in activating microglial P2RY12 receptors to regulate neurovascular structure and function.
Increasing global temperatures are having a profound impact in the Arctic, including the dramatic loss of multiyear sea ice in 2007 that has continued to the present. The majority of life in the ...Arctic is microbial and the consequences of climate-mediated changes on microbial marine food webs, which are responsible for biogeochemical cycling and support higher trophic levels, are unknown. We examined microbial communities over time by using high-throughput sequencing of microbial DNA collected between 2003 and 2010 from the subsurface chlorophyll maximum (SCM) layer of the Beaufort Sea (Canadian Arctic). We found that overall this layer has freshened and concentrations of nitrate, the limiting nutrient for photosynthetic production in Arctic seas, have decreased. We compared microbial communities from before and after the record September 2007 sea ice minimum and detected significant differences in communities from all three domains of life. In particular, there were significant changes in species composition of Eukarya, with ciliates becoming more common and heterotrophic marine stramenopiles (MASTs) accounting for a smaller proportion of sequences retrieved after 2007. Within the Archaea, Marine Group I Thaumarchaeota, which earlier represented up to 60% of the Archaea sequences in this layer, have declined to <10%. Bacterial communities overall were less diverse after 2007, with a significant decrease of the Bacteroidetes. These significant shifts suggest that the microbial food webs are sensitive to physical oceanographic changes such as those occurring in the Canadian Arctic over the past decade.
γ-Aminobutyric acid (GABA)ergic inputs are strategically positioned to gate synaptic integration along the dendritic arbor of pyramidal cells. However, their spatiotemporal dynamics during behavior ...are poorly understood. Using an optical-tagging electrophysiological approach to record and label somatostatin-expressing (Sst) interneurons (GABAergic neurons specialized for dendritic inhibition), we discovered a layer-specific modulation of their activity in behaving mice. Sst interneuron subtypes, residing in different cortical layers and innervating complementary laminar domains, exhibited opposite activity changes during transitions to active wakefulness. The relative weight of vasoactive intestinal peptide–expressing (Vip) interneuron–mediated inhibition of distinct Sst interneurons and cholinergic modulation determined their in vivo activity. These results reveal a state-dependent laminar influence of Sst interneuron–mediated inhibition, with implications for the compartmentalized regulation of dendritic signaling in the mammalian neocortex.
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