Search

Human babesiosis is a life-threatening infectious disease that causes societal and economic impact worldwide. Several species of Babesia cause babesiosis in terrestrial vertebrates, including humans. A one-day clinic was held in Ontario, Canada, to see if a red blood cell parasite, which is present in blacklegged ticks, Ixodes scapularis, is present in humans. Based on PCR testing and DNA sequencing of the 18S rRNA gene, we unveiled B. odocoilei in two of 19 participants. DNA amplicons from these two patients are almost identical matches with the type strains of B. odocoilei in GenBank. In addition, the same two human subjects had the hallmark symptoms of human babesiosis, including night sweats, chills, fevers, and profound fatigue. Based on symptoms and molecular identification, we provide substantive evidence that B. odocoilei is pathogenic to humans. Dataset reveals that B. odocoilei serologically cross-reacts with Babesia duncani. Clinicians must realize that there are more than two Babesia spp. in North America that cause human babesiosis. This discovery signifies the first report of B. odocoilei causing human babesiosis.

Tick-borne zoonotic diseases have an economic and societal impact on the well-being of people worldwide. In the present study, a high frequency of Babesia odocoilei, a red blood cell parasite, was observed in the Huronia area of Ontario, Canada. Notably, 71% (15/21) blacklegged ticks, Ixodes scapularis, collected from canine and feline hosts were infected with B. odocoilei. Consistent with U.S. studies, 12.5% (4/32) of questing I. scapularis adults collected by flagging in various parts of southwestern Ontario were positive for B. odocoilei. Our data show that all B. odocoilei strains in the present study have consistent genetic identity, and match type strains in the GenBank database. The high incidence of B. odocoilei in the Huronia area indicates that this babesial infection is established, and is cycling enzootically in the natural environment. Our data confirm that B. odocoilei has wide distribution in southern Ontario.

Songbirds widely disperse ticks that carry a diversity of pathogens, some of which are pathogenic to humans. Among ticks commonly removed from songbirds, the blacklegged tick, Ixodes scapularis, can harbor any combination of nine zoonotic pathogens, including Babesia species. From May through September 2019, a total 157 ticks were collected from 93 songbirds of 29 species in the Canadian provinces of Ontario and Québec. PCR testing for the 18S gene of Babesia species detected Babesia odocoilei in 12.63% of I. scapularis nymphs parasitizing songbirds in Ontario and Québec; none of the relatively small numbers of Ixodes muris, Ixodes brunneus, or Haemaphysalis leporispalustris were PCR-positive. For ticks at each site, the prevalence of B. odocoilei was 16.67% in Ontario and 8.89% and 5.26% in Québec. Of 31 live, engorged I. scapularis larvae and nymphs held to molt, 25 ticks completed the molt; five of these molted ticks were positive for B. odocoilei. PCR-positive ticks were collected from six bird species-namely, Common Yellowthroat, Swainson's Thrush, Veery, House Wren, Baltimore Oriole, and American Robin. Phylogenetic analysis documented the close relationship of B. odocoilei to Babesia canis canis and Babesia divergens, the latter a known pathogen to humans. For the first time in Canada, we confirm the transstadial passage of B. odocoilei in I. scapularis molting from larvae to nymphs. A novel host record reveals I. scapularis on a Palm Warbler. Our findings show that B. odocoilei is present in all mobile life stages of I. scapularis, and it is widely dispersed by songbirds in Ontario and Québec.

This study provides a novel method of documenting established populations of bird-feeding ticks. Single populations of the blacklegged tick, Ixodes scapularis, and the rabbit tick, Haemaphysalis leporispalustris, were revealed in southwestern Québec, Canada. Blacklegged tick nymphs and, similarly, larval and nymphal rabbit ticks were tested for the Lyme disease bacterium, Borrelia burgdorferi sensu lato (Bbsl), using PCR and the flagellin (flaB) gene, and 14 (42%) of 33 of blacklegged tick nymphs tested were positive. In contrast, larval and nymphal H. leporsipalustris ticks were negative for Bbsl. The occurrence of Bbsl in I. scapularis nymphs brings to light the presence of a Lyme disease endemic area at this songbird nesting locality. Because our findings denote that this area is a Lyme disease endemic area, and I. scapularis is a human-biting tick, local residents and outdoor workers must take preventive measures to avoid tick bites. Furthermore, local healthcare practitioners must include Lyme disease in their differential diagnosis.

Failure of central nervous system projection neurons to spontaneously regenerate long-distance axons underlies irreversibility of white matter pathologies. A barrier to axonal regenerative research is that the axons regenerating in response to experimental treatments stall growth before reaching postsynaptic targets. Here, we test the hypothesis that the interaction of regenerating axons with live oligodendrocytes, which were absent during developmental axon growth, contributes to stalling axonal growth. To test this hypothesis, first, we used single cell RNA-seq (scRNA-seq) and immunohistology to investigate whether post-injury born oligodendrocytes incorporate into the glial scar after optic nerve injury. Then, we administered demyelinationinducing cuprizone and stimulated axon regeneration by Pten knockdown (KD) after optic nerve crush. We found that postinjury born oligodendrocyte lineage cells incorporate into the glial scar, where they are susceptible to the demyelination diet, which reduced their presence in the glial scar. We further found that the demyelination diet enhanced Pten KD-stimulated axon regeneration and that localized cuprizone injection promoted axon regeneration. We also present a resource for comparing the gene expression of scRNA-seq-profiled normal and injured optic nerve oligodendrocyte lineage cells. [ABSTRACT FROM AUTHOR]

Background: Patients with colorectal cancer who seek to improve their knowledge of health and treatment options can now access in a few seconds data that would previously have required hours of research. Our aim was to evaluate the attitudes of patients toward Web browsing for information on colorectal cancer. Methods: We surveyed all patients attending a colorectal cancer follow-up clinic between January and August 2007 on their use of the Internet to obtain information on colorectal cancer. Results: In all, 439 patients with mean age of 68.6 years participated in the study. Of these, 24% reported using the Internet to obtain colorectal cancer information. Most participants used the Google search engine. Only 13% of participants confirmed that colorectal cancer information on the Internet was helpful in decision-making. Patients under the age of 65 years were more likely to have Internet access (p < 0.001), more likely to use the Internet to find colorectal cancer information (p = 0.005) and more likely to access a site recommended by a colorectal specialist (p = 0.002). Among Internet users, men were slightly more likely than women to use the Internet, although the difference was not significant (p = 0.20). Conclusion: The Internet is a useful tool for disseminating information about colorectal cancer. The best sites are still difficult for patients to distinguish from the thousands of sites returned by search engines. This study demonstrates that the level of potential interest is sufficient to justify the development of a departmental or regional colorectal cancer network of websites and indicates areas of interest for patients. Contexte : Les patients atteints d'un cancer colorectal qui souhaitent a mieux connaitre leur etat et les possibilites de traitement peuvent maintenant consulter en quelques secondes des donnees qu'il leur aurait fallu chercher pendant des heures auparavant. Nous voulions evaluer les attitudes des patients a l'egard de la recherche sur Internet d'information au sujet du cancer colorectal. Methodes : Nous avons sonde tous les patients qui se sont presentes a une clinique de suivi du cancer colorectal entre janvier et aout 2007 au sujet de l'utilisation d'Internet pour obtenir de l'information sur le cancer colorectal. Resultats : Au total, 439 patients qui avaient en moyenne 68,6 ans ont participe a l'etude et 24 % d'entre eux ont declare avoir cherche sur Internet de l'information au sujet du cancer colorectal. La plupart des participants ont utilise le moteur de recherche Google. Seulement 13% des participants ont confirme que l'information sur le cancer colorectal trouvee sur Internet les a aides a prendre une decision. Les patients de moins de 65 ans etaient plus susceptibles d'avoir acces a Internet (p < 0,001), plus susceptibles d'utiliser Internet pour trouver de l'information sur le cancer colorectal (p = 0,005) et plus susceptibles de consulter un site recommande par un specialiste du cancer colorectal (p = 0,002). Chez les internautes, les hommes etaient un peu plus susceptibles que les femmes d'utiliser Internet, meme si la difference n'etait pas significative (p = 0,20). Conclusion : Internet est un outil utile pour diffuser de l'information sur le cancer colorectal. Il demeure difficile pour les patients de distinguer les meilleurs sites parmi les milliers decouverts par les moteurs de recherche. Cette etude demontre que le niveau d'interet possible suffit pour justifier la creation d'un reseau de sites web sur le cancer colorectal au niveau du departement ou de la region et precise les domaines d'interet des patients., The Internet is becoming a widely accepted and accessible medium for the dissemination of information on colorectal cancer among patients, their relatives, the general public, allied health professionals and doctors. [...]