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1.
J Parasitol ; 109(6): 592-602, 2023 12 01.
Article de Anglais | MEDLINE | ID: mdl-38109931

RÉSUMÉ

Trypanosome infections containing multiple morphologies have been described from all classes of vertebrates, including mammals, birds, non-avian reptiles, amphibians, and fish. These mixed infections make it challenging to evaluate trypanosome diversity, as it is not immediately clear whether the forms present in the bloodstream represent different species or a single pleomorphic species. Amphibians are common hosts for trypanosomes and are often infected by multiple trypanosome morphologies in the bloodstream. Based on morphological observations and life cycle studies, many authors have considered multiple trypanosome morphotypes found infecting the same frogs to be a single pleomorphic species. However, molecular evidence supporting pleomorphic trypanosome species in amphibians is lacking, primarily because linking sequence data to bloodstream trypanosome morphology in mixed infections is extremely challenging. Here we present methods to isolate individual trypanosome cells of 6 morphotypes from frog blood for nested PCR of the 18S rRNA and gGAPDH genes. Single trypanosome cells were isolated by dilution and 3 DNA extraction methods, and 5 nested PCR primer regimes were utilized to optimize amplification from very low starting concentrations. The success rates of extraction methods ranged from 29 to 50% with the use of a Direct PCR kit having the highest success rate. Although the success rate varied in the different combinations of extraction methods and primer regimes, multiple individuals of all 6 trypanosome morphotypes were sequenced for both genes in a novel way that links sequence data to cell morphology by observing isolated cells with a microscope before PCR amplification. All 6 morphologically distinguishable morphotypes coinfecting a frog were genetically distinct. The only other recent molecular study on amphibian trypanosomes also found genetic differences between morphotypes in multiple infections. Together these studies suggest that the occurrence of pleomorphism may be overestimated in amphibian trypanosomes. The methods presented here offer a promising solution to characterize trypanosome diversity within multiple morphotype infections.


Sujet(s)
Co-infection , Trypanosoma , Animaux , Co-infection/médecine vétérinaire , Phylogenèse , ARN ribosomique 18S/génétique , Oiseaux/génétique , Mammifères/génétique , Anura
2.
J Stroke Cerebrovasc Dis ; 31(8): 106508, 2022 Aug.
Article de Anglais | MEDLINE | ID: mdl-35605385

RÉSUMÉ

OBJECTIVES: We aimed to determine which factors influence recovery in stroke patients with pre-existing disability, as these patients are often excluded from acute treatment trials. MATERIALS AND METHODS: A prospective stroke center registry of admitted patients from 2019-2021 with acute stroke was queried for patients with pre-stroke modified Rankin Scale (mRS) of 0-4. Multivariable logistic regression was used to estimate odds of functional recovery at 90 days (mRS 0-2, or return to pre-stroke mRS). RESULTS: Of 1228 patients, 856 (70%) included patients had pre-stroke mRS 0-4 and 90-day follow-up mRS. The median age was 68y (IQR 59-78), with a median National Institutes of Health Stroke Scale (NIHSS) of 5 (IQR 2-17). Compared to those with mRS 0-1 (n = 596), patients with pre-stroke mRS of 2 (n = 126), 3 (n = 96), or 4 (n = 38) were less likely to achieve functional recovery in univariate analysis. After multivariable adjustment, odds of functional recovery were significantly lower for patients with pre-stroke mRS of 2 (adjusted odds ratio [ORadj] 0.45, 95% confidence interval [CI] 0.28-0.72), but not those with pre-stroke mRS of 3 (ORadj 1.14, 95%CI 0.66-1.97) or 4 (ORadj 0.50, 95%CI 0.21-1.19). Older age (ORadj per year 0.97, 95%CI 0.95-0.97) and higher NIHSS (ORadj per point 0.89, 95%CI 0.88-0.91) were associated with lower odds of functional recovery, while thrombolysis (ORadj 2.43, 95%CI 1.42-4.15) and a cryptogenic stroke mechanism (ORadj 1.57, 95%CI 1.07-2.31) were protective. CONCLUSIONS: Recovery of patients with pre-existing disability was driven by age and stroke severity. Thrombolysis remained predictive of recovery irrespective of age, stroke severity, and pre-stroke disability.


Sujet(s)
Encéphalopathie ischémique , Accident vasculaire cérébral , Sujet âgé , Évaluation de l'invalidité , Humains , Facteurs de risque , Accident vasculaire cérébral/diagnostic , Accident vasculaire cérébral/thérapie , Facteurs temps , Résultat thérapeutique
3.
J Stroke Cerebrovasc Dis ; 31(5): 106427, 2022 May.
Article de Anglais | MEDLINE | ID: mdl-35279004

RÉSUMÉ

INTRODUCTION: Ipsilateral nonstenotic (<50%) internal carotid artery (ICA) plaque, cardiac atriopathy, and patent foramen ovale (PFO) may account for a substantial proportion of embolic stroke of undetermined source (ESUS). METHODS: Consecutive stroke patients at our center (2019-2021) with unilateral, anterior circulation ESUS were categorized into the following mutually exclusive etiologies: (1) nonstenotic ipsilateral ICA plaque (NSP, ≥3mm in maximal axial diameter), (2) sex-adjusted mod-to-severe left atrial enlargement (LAE), (3) PFO, and (4) "occult ESUS" (patients who failed to meet criteria for these 3 groups). Descriptive statistics and multivariable logistic regression were used to model group characteristics. RESULTS: Of 132 included patients, the median age was 65 (IQR 56-73), 74 (56%) of whom were White, and 54 (41%) were female. Twenty-one patients (16%) had NSP proximal to the infarct territory, 17 (13%) had LAE, 9 (7%) had a PFO, and 85 (64%) had no other mechanism. Patients with LAE were older (p=0.004), and had more frequent intracranial occlusions of the internal carotid and proximal middle cerebral artery (p=0.048), while tobacco use was most commonly found among patients with NSP (75%) when compared to other ESUS groups (p=0.02). Five of 9 patients with LAE who underwent outpatient telemetry had paroxysmal atrial fibrillation (56%), while zero patients with PFO or NSP had paroxysmal atrial fibrillation (p=0.005). Older age (adjusted OR [aOR] 1.05, 95%CI 1.03-1.07), coronary artery disease (aOR 3.22, 95%CI 1.61-6.44) and hypertension (aOR 2.16, 95%CI 1.14-4.06) were independently associated with LAE, while only tobacco use was associated with NSP when compared to other ESUS subclassifiers (OR 3.18, 95%CI 1.08-0.42). Age and tobacco use were both inversely associated with PFO (aOR 0.93, 95%CI 0.88-0.98, and aOR 0.10, 95%CI 0.02-0.90, respectively). CONCLUSIONS: Certain clinical and radiographic features may be useful in predicting the proximal source of occult cerebral emboli, and can be used for cost-effective outpatient diagnostic testing.


Sujet(s)
Fibrillation auriculaire , Accident vasculaire cérébral embolique , Foramen ovale perméable , Embolie intracrânienne , Plaque d'athérosclérose , Accident vasculaire cérébral , Sujet âgé , Fibrillation auriculaire/complications , Femelle , Foramen ovale perméable/complications , Foramen ovale perméable/imagerie diagnostique , Humains , Embolie intracrânienne/complications , Embolie intracrânienne/étiologie , Mâle , Plaque d'athérosclérose/complications , Facteurs de risque , Accident vasculaire cérébral/diagnostic
4.
J Parasitol ; 107(5): 739-761, 2021 09 01.
Article de Anglais | MEDLINE | ID: mdl-34546335

RÉSUMÉ

The role of invertebrates in some acanthocephalan life cycles is unclear because juvenile acanthocephalans are difficult to identify to species using morphology. Most reports suggest acanthocephalans from turtle definitive hosts use ostracods as intermediate hosts and snails as paratenic hosts. However, laboratory studies of the life cycle suggest that ostracods and snails are both required hosts in the life cycle. To elucidate the role of ostracods and snails in acanthocephalan life cycles better, we collected 558 freshwater snails of 2 species, including Planorbella cf. Planorbella trivolvis and Physa acuta, from 23 wetlands in Oklahoma, U.S.A., and examined them for acanthocephalan infections. Additionally, we examined 37,208 ostracods of 4 species, Physocypria sp. (morphotype 1), Cypridopsis sp., Stenocypris sp., and Physocypria sp. (morphotype 2) for juvenile acanthocephalans from 2 wetlands in Oklahoma. Juvenile acanthocephalans were morphologically characterized, and the complete internal transcribed spacer (ITS) region of nuclear rDNA was sequenced from acanthocephalans infecting 11 ostracod and 13 snail hosts. We also sampled 10 red-eared slider turtles, Trachemys scripta elegans, and 1 common map turtle, Graptemys geographica, collected from Oklahoma, Arkansas, and Texas and recovered 1,854 adult acanthocephalans of 4 species. The ITS of 17 adult acanthocephalans of 4 species from turtle hosts were sequenced and compared to juvenile acanthocephalan sequences from ostracod and snail hosts from this study and GenBank to determine conspecificity. Of the 23 locations sampled for snails, 7 (30%) were positive for juvenile acanthocephalans in the genus Neoechinorhynchus. The overall prevalence and mean intensity of acanthocephalans in Planorbella cf. P. trivolvis and P. acuta were 20% and 2 (1-6) and 2% and 1 (1), respectively. In contrast, only 1 of 4 species of ostracods, Physocypria sp. (morphotype 1), was infected with larval/juvenile Neoechinorhynchus spp. with an overall prevalence of 0.1% and a mean intensity of 1 (1-2). Although 4 species of acanthocephalans infected turtle definitive hosts, including Neoechinorhynchus chrysemydis, Neoechinorhynchus emydis, Neoechinorhynchus emyditoides, and Neoechinorhynchus pseudemydis, all the ITS sequences from cystacanths infecting snail hosts were conspecific with N. emydis. In contrast, the ITS sequences from larval/juvenile acanthocephalans from ostracods were conspecific with 2 species of acanthocephalans from turtles (N. emydis and N. pseudemydis) and 1 species of acanthocephalan from fish (Neoechinorhynchus cylindratus). These results indicate that N. emydis infects freshwater snails, whereas other species of Neoechinorhynchus appear not to infect snail hosts. We document new ostracod and snail hosts for Neoechinorhynchus species, including the first report of an ostracod host for N. pseudemydis, and we provide novel molecular barcodes that can be used to determine larva, juvenile, and adult conspecificity of Neoechinorhynchus species.


Sujet(s)
Acanthocephala/génétique , Crustacea/parasitologie , Escargots/parasitologie , Tortues/parasitologie , Acanthocephala/anatomie et histologie , Acanthocephala/isolement et purification , Acanthocephala/pathogénicité , Animaux , ADN des helminthes/composition chimique , ADN des helminthes/isolement et purification , Femelle , Eau douce , Mâle , Saisons , Analyse spatiale
5.
Phys Rev Lett ; 127(25): 251303, 2021 Dec 17.
Article de Anglais | MEDLINE | ID: mdl-35029430

RÉSUMÉ

A cosmological first-order phase transition is expected to produce a stochastic gravitational wave background. If the phase transition temperature is on the MeV scale, the power spectrum of the induced stochastic gravitational waves peaks around nanohertz frequencies, and can thus be probed with high-precision pulsar timing observations. We search for such a stochastic gravitational wave background with the latest data set of the Parkes Pulsar Timing Array. We find no evidence for a Hellings-Downs spatial correlation as expected for a stochastic gravitational wave background. Therefore, we present constraints on first-order phase transition model parameters. Our analysis shows that pulsar timing is particularly sensitive to the low-temperature (T∼1-100 MeV) phase transition with a duration (ß/H_{*})^{-1}∼10^{-2}-10^{-1} and therefore can be used to constrain the dark and QCD phase transitions.

6.
Science ; 366(6462): 231-234, 2019 10 11.
Article de Anglais | MEDLINE | ID: mdl-31558577

RÉSUMÉ

Present-day galaxies are surrounded by cool and enriched halo gas extending for hundreds of kiloparsecs. This halo gas is thought to be the dominant reservoir of material available to fuel future star formation, but direct constraints on its mass and physical properties have been difficult to obtain. We report the detection of a fast radio burst (FRB 181112), localized with arcsecond precision, that passes through the halo of a foreground galaxy. Analysis of the burst shows that the halo gas has low net magnetization and turbulence. Our results imply predominantly diffuse gas in massive galactic halos, even those hosting active supermassive black holes, contrary to some previous results.

7.
Parasitol Res ; 117(2): 461-470, 2018 Feb.
Article de Anglais | MEDLINE | ID: mdl-29280071

RÉSUMÉ

Previous studies on Gyrinicola batrachiensis indicate that these pinworms have distinct reproductive strategies dependent on the development time to metamorphosis of their anuran tadpole hosts. In tadpoles of amphibian species with short developmental periods (a few weeks), female nematodes reproduce parthenogenetically, and only produce thick-shelled eggs used as transmission agents from tadpole to tadpole. In contrast, nematodes in tadpoles with longer larval developmental periods (months to years) reproduce by haplodiploidy, and females produce thick-shelled as well as autoinfective thin-shelled eggs. However, recent investigations on the haplodiploidy strain of G. batrachiensis indicate that plasticity exists in the ability of these nematodes to produce thin-shelled autoinfective eggs when these nematodes infect tadpoles of co-occurring amphibian species. Yet, little information is available on the potential mechanism for this reproductive plasticity because few co-occurring amphibian species have been examined for the reproductive strategies of these nematodes. Therefore, our goals were to document field host specificity and reproductive strategies of nematode populations in tadpoles of five co-occurring amphibian species that varied in their larval developmental periods. Additionally, we evaluated adult worm morphology from each infected amphibian species to assess any differences in worm development and reproductive strategy of pinworm populations in different amphibian species. Of the five amphibian species examined, four were infected with the haplodiploid strain of G. batrachiensis. Prevalence of G. batrachiensis ranged from a high of 83% in Acris blandchardi to a low of 15% in Pseudacris clarkii; whereas mean intensity was highest for Rana sphenocephala (10 ± 10.36) and lowest for Hyla chrysoscelis (3.23 ± 3.35). Prevalence appeared to be controlled by tadpole ecology and life history, while mean intensity appeared to be controlled by tadpole physiology and worm reproductive strategy, but not necessarily the developmental period of each anuran species. G. batrachiensis observed in long developing tadpoles of R. sphenocephala had high mean intensities and conformed to the haplodiploidy reproductive strategy with both male and female worms being present, and females produced thick-shelled and thin-shelled eggs. In contrast, tadpoles of A. blanchardi, H. chrysoscelis, and P. clarkii, which varied in their developmental times from long to short, had relatively low mean intensities and contained both male and female G. batrachiensis. However, female worms only produced thick-shelled eggs in these hosts. Importantly, morphological differences existed among female worms recovered from R. sphenocephala and female worms recovered from A. blanchardi tadpoles with long developmental periods. These data strongly suggest that when the haplodiploidy strain of G. batrachiensis is shared by tadpoles of different amphibian species, species-specific differences in interactions between these nematodes and their development in different amphibian host species have a strong influence on the reproductive plasticity of these nematodes.


Sujet(s)
Anura/parasitologie , Oxyurose/épidémiologie , Enterobius/croissance et développement , Larve/parasitologie , Ovule/physiologie , Animaux , Enterobius/physiologie , Femelle , Étapes du cycle de vie , Mâle , Métamorphose biologique , Parthénogenèse/physiologie , Prévalence , Reproduction/physiologie , Spécificité d'espèce
8.
J Am Anim Hosp Assoc ; 52(5): 269-76, 2016.
Article de Anglais | MEDLINE | ID: mdl-27487349

RÉSUMÉ

Chronic vomiting in cats is a common presenting problem seen in veterinary practice today. The initial step when presented with a vomiting patient is to differentiate between vomiting and regurgitation or dysphagia. There are numerous causes for chronic vomiting in cats, and therefore a detailed and comprehensive patient history and a systematic diagnostic approach are key steps in determining the cause for vomiting and the most appropriate treatment plan. Common causes for chronic vomiting in cats may include inflammatory bowel disease, food allergy, gastrointestinal motility disorders, neoplasia, and extra-gastrointestinal diseases, such as renal disease, hepatobiliary disease, and hyperthyroidism.


Sujet(s)
Maladies des chats/étiologie , Vomissement/médecine vétérinaire , Animaux , Maladies des chats/diagnostic , Chats , Maladie chronique , Vomissement/complications , Vomissement/diagnostic
9.
Zootaxa ; 4088(4): 515-30, 2016 Mar 11.
Article de Anglais | MEDLINE | ID: mdl-27394355

RÉSUMÉ

In this study, we sampled aquatic snails for the presence of hairworm cysts from 46 streams in Payne County, Oklahoma. Gordiid cysts were found at 70 % (32/46) of sites examined. Based on cyst morphology, we were able to identify three morphological types of gordiid cysts, including Paragordius, Gordius, and Chordodes/Neochordodes. Using our gordiid cyst presence data in conjunction with environmental variables, we developed an ecological niche model using Maxent to identify areas suitable for snail infections with gordiids. The model successfully predicted all presence localities of gordiid cysts in snails over a geographic area of 1,810 km2. We used this information, along with arthropod host infections and crowdsourcing, citizen scientists sampling for adult free-living worms during peak emergent times in areas predicted suitable by the model, to document Paragordius varius, Chordodes morgani, and a new species of gordiid (Gordius n. sp.). To our knowledge, this is the first ecological niche model attempted on such a narrow geographic scale (county level) that recovered known locations successfully. We provide new scanning electron micrographs and molecular data for these species. Our field data and ecological niche model clearly indicate that gordiid cysts are easy to detect in the environment and together these sampling techniques can be useful in discovering new species of gordiids, even in relatively well sampled areas for these cryptic parasites.


Sujet(s)
Helminthes/classification , Helminthes/croissance et développement , Répartition des animaux , Structures anatomiques de l'animal/anatomie et histologie , Structures anatomiques de l'animal/croissance et développement , Animaux , Biodiversité , Mensurations corporelles , Écosystème , Femelle , Helminthes/anatomie et histologie , Mâle , Taille d'organe , Escargots/parasitologie
10.
Healthc Q ; 18(3): 34-42, 2015.
Article de Anglais | MEDLINE | ID: mdl-26718252

RÉSUMÉ

Recent trends show an increase in the prevalence and costs associated with managing individuals with multimorbidities. Enabling better care for these individuals requires system-level changes such as the shift from a focus on a single disease or single service to multimorbidities and integrated systems of care. In this paper, a novel patient-centred redesign framework that was developed to support system-level process changes in four service areas has been discussed. The novelty of this framework is that it is embedded in patient perspectives and in the chronic care model as the theoretical foundation. The aims of this paper are to present an application of the framework in the context of four chronic disease prevention and management services, and to discuss early results from the pilot initiative along with an overview of the spread opportunities for this initiative.


Sujet(s)
Maladie chronique/thérapie , Comorbidité , Innovation organisationnelle , Soins centrés sur le patient/organisation et administration , Canada , Maladie chronique/prévention et contrôle , Prestations des soins de santé/organisation et administration , Humains , Modèles d'organisation , Amélioration de la qualité/organisation et administration
11.
Healthc Q ; 17(3): 48-54, 2014.
Article de Anglais | MEDLINE | ID: mdl-25591610

RÉSUMÉ

Chronic disease is a highly expensive but preventable problem to the healthcare system. Evidence suggests that impacting modifiable behaviours and risk management factors in the areas of physical inactivity, unhealthy diet, stress and obesity can alleviate the burden of chronic disease problem to a large extent. Despite this recognition, the challenge is embedding these recognized priorities into the community and in primary care in a sustainable and meaningful manner. Primary Health Care in Capital Health responded to this challenge by developing and implementing a free, interprofessional and community-based service, namely, the Community Health Teams (CHTs), that offers health and wellness, risk factor management, wellness navigation and behaviour-based programming. In this paper, the development and implementation of the CHTs are discussed. Preliminary outcomes for the model are significant and promising. Formal and large-scale studies are planned to validate these outcomes with additional research rigour.


Sujet(s)
Maladie chronique/prévention et contrôle , Services de santé communautaires/organisation et administration , Promotion de la santé/méthodes , Canada , Services de santé communautaires/méthodes , Exercice physique , Promotion de la santé/organisation et administration , Humains , Modèles d'organisation , Mise au point de programmes , Évaluation de programme , Facteurs de risque , Gestion du risque/méthodes , Gestion du risque/organisation et administration
12.
J Parasitol ; 99(3): 397-402, 2013 Jun.
Article de Anglais | MEDLINE | ID: mdl-23252693

RÉSUMÉ

Hairworms infect terrestrial arthropods and are 1 of the most understudied groups of parasites. Recently, life cycles of 2 gordiids (Paragordius varius and Paragordius obamai) have been domesticated in the laboratory. We tested the viability of laboratory reared and post-frozen larval and cyst stages of the North American gordiid, P. varius , frozen at -80 C for 7 mo, and the viability of field collected and post-frozen cysts of the African (P. obamai) and North American ( P. varius ) gordiid frozen at -20 C for 2 mo. All snails exposed to post-frozen or control P. varius larvae became infected with cysts, and there was no significant difference in prevalence or mean intensity of cysts among control or experimental snail groups. As with larvae, no significant differences were observed in prevalence or mean intensity of emerging worms from crickets infected with post-frozen or control P. obamai or P. varius cysts. All female P. obamai and P. varius worms from control and post-frozen cyst infections laid eggs and larvae hatched from some of these eggs. Survival and cyst formation of P. varius larvae exposed to different combinations of drying and/or freezing temperatures indicated that gordiid larvae have the ability to survive drying and freezing, but survival significantly increases during freezing at lower temperatures. The major contribution of our study is the demonstration that gordiid larval and cyst stages can survive freezing temperatures to infect and develop in the next host.


Sujet(s)
Congélation , Gryllidae/parasitologie , Helminthes/physiologie , Étapes du cycle de vie , Escargots/parasitologie , Animaux , Dessiccation , Femelle , Helminthes/croissance et développement , Larve/physiologie , Étapes du cycle de vie/physiologie , Mâle
13.
Healthc Q ; 16(2): 36-42, 2013.
Article de Anglais | MEDLINE | ID: mdl-24863448

RÉSUMÉ

Healthcare is in a constant state of change and evolution driven by a multitude of complex factors and interactions. Consequently, organizations, teams and individuals in healthcare have to habitually realign their working relationships. Furthermore, research has shown that "working together" relationships fail in the absence of a defined framework. In this research, a novel framework and a tool kit for working together have been developed and evaluated. The framework has a formal process to articulate the intended purpose/outcome, clearly align the type of working relationship with the purpose and identify the barriers and facilitators to working relationships in healthcare.


Sujet(s)
Comportement coopératif , Prestations des soins de santé/organisation et administration , Gestion du personnel/méthodes , Mise au point de programmes , Relations interprofessionnelles , Mise au point de programmes/méthodes , Évaluation de programme/méthodes
14.
J Pediatr Pharmacol Ther ; 13(4): 226-32, 2008 Oct.
Article de Anglais | MEDLINE | ID: mdl-23055881

RÉSUMÉ

OBJECTIVE: The purpose of this study was to determine if a prescription review service, at the time of discharge, enhances the accuracy and safety of prescriptions written at an academic pediatric hospital. METHODS: The study took place over a 30-day period and included prescriptions written for patients being discharged from the General Pediatric and Pediatric Intensive Care Services at the University of Maryland Hospital for Children, a 120-bed academic pediatric hospital. Discharge prescriptions were faxed to the Inpatient Pediatric Pharmacy where they were reviewed by a pediatric clinical pharmacist. Specific review criteria were aimed at detecting prescribing errors that included patient identification, medication selection, dosing, and therapy omission. A prescriber was notified via alpha page when errors were identified and advised on corrective measures. Interventions were compiled and analyzed to determine the overall impact of the discharge prescription review program. RESULTS: Over the 30-day period, 74 discharge prescriptions were reviewed by a pediatric clinical pharmacist. At least one prescribing error was detected in 81% of the prescriptions reviewed. Overall, 101 prescribing errors were documented and included patient identification, medication selection and dose calculation errors. The estimated cost-savings attributed to the interventions is approximately $7670. CONCLUSION: Through the discharge prescription review program, the pediatric clinical pharmacists were able to make interventions on the majority of prescriptions reviewed. The types of errors that required interventions have been identified as potential sources for major medication errors in the pediatric population. We concluded that the review of discharge prescriptions by a pediatric clinical pharmacist was an effective method of preventing prescribing errors in the pediatric environment.

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