Mosquito Fauna And Prevalence Of Avian Malaria In The Turtle Mountains, North Dakota

Avian malaria is a disease caused by intracellular parasites transmitted by mosquitoes and is detrimental to individual birds and their populations. Although it is sub-lethal in most instances, avian malaria can result in anemia, lower fertility, and reduced migration ability. The Turtle Mountains is a unique ecoregion in North Dakota and provides habitat for various bird and mosquito species that differ from other parts of the state. Previous research has defined the mosquito fauna and occurrence of avian malaria in the Red River Valley region of eastern North Dakota and Northwest Minnesota; however, no research has been conducted in the Turtle Mountains. Mosquito population dynamics are vital to understanding the transmission dynamics of malaria. This research had three objectives. First, the species composition, seasonal abundances, and malaria infection status of host-seeking mosquitoes were determined throughout two summer seasons. Abundances and species compositions of mosquitoes differed from 2019 to 2020, but there were no haemosporidian infections identified. Second, blood from local and migrating birds in the Turtle Mountains was collected to establish the occurrence of avian malaria in the region. This study determined the prevalence of avian haemosporidian parasites in both migratory birds and birds that remain permanent residents throughout the seasons. Avian haemosporidians were present in both local and migratory birds captured in the Turtle Mountains. Based on this research in the Turtle Mountains, it appears that the avian haemosporidian transmission occurs for migratory birds prior to their arrival the Turtle Mountain ecoregion. Third, laboratory studies determined the relative competencies of different mosquito species to support the development of Plasmodium. Despite successful infection of Plasmodium in some Culex pipiens, the parasite was unable to fully develop into sporozoites within the vector. Plasmodium was unable to develop into oocysts in Aedes aegypti or Culex tarsalis. Future studies should focus on climate change and its impact on the mosquito populations of the Turtle Mountains. The introduction of a new competent vector or the increase of a current competent vector would greatly influence the transmission of avian parasites. Increased transmission of current parasites or the introduction of a new parasite species would negatively impact bird populations of the area

Differential susceptibilities of Anopheles albimanus and Anopheles stephensi mosquitoes to ivermectin

Background Vector control is a crucial element of anti-malaria campaigns and works best when there is a thorough knowledge of the biology and behaviour of the Anopheles vector species responsible for transmitting malaria within a given locale. With the push to eradicate malaria stronger than ever, there is a growing need to develop and deploy control strategies that exploit the behavioural attributes of local vector species. This is especially true in regions where the vectors are exophagic (i.e., prefer to bite outdoors), exophilic (i.e., prefer to remain outdoors), and zoophagic (i.e., as likely to feed on non-humans as humans). One promising strategy targeting vectors with these behavioural traits is the administration of avermectin-based endectocides, such as ivermectin, to humans and livestock. When ingested in a blood meal, ivermectin has been shown to reduce mosquito survivorship and fecundity in a number of Anopheles species. In this study, the relative toxicity of ivermectin was compared between two zoophagic, exophilic malaria vectors—Anopheles albimanus and Anopheles stephensi. Results Toxicity of ivermectin was assessed using membrane feedings, intrathoracic injections, and mosquito feedings on treated mice. When ingested in a blood meal, ivermectin was much less toxic to An. albimanus (4-day oral LC50 = 1468 ng/ml) than to An. stephensi (4-day oral LC50 = 7 ng/ml). However when injected into the haemocoel of An. albimanus, ivermectin was much more toxic (3-day parenteral LC50 = 188 ng/ml). Because the molecular targets of ivermectin (i.e., glutamate-gated chloride channels) reside outside the midgut in nerves and muscles, this suggests that ingested ivermectin was not readily absorbed across the midgut of An. albimanus. In contrast, ivermectin was considerably more toxic to An. stephensi when ingested (4-day oral LC50 = 7 ng/ml) than when injected (3-day parenteral LC50 = 49 ng/ml). This suggests that metabolic by-products from the digestion of ivermectin may play a role in the oral toxicity of ivermectin to An. stephensi. Blood meal digestion and subsequent oviposition rates were significantly hindered in both species by ingested ivermectin but only at concentrations at or above their respective oral LC50 concentrations. To test mosquitocidal activity of ivermectin in a live host system, two groups of three mice each received subcutaneous injections of either ivermectin (600 µg/kg BW) or saline (control). One day after injection, the ivermectin-treated mice (n = 3) exhibited significant mosquitocidal activity against both An. stephensi (85% mortality vs 0% in control-fed) and, to a lesser degree, An. albimanus (44% mortality vs 11% in control-fed). At 3 days, the mosquitocidal activity of ivermectin-treated mice waned and was effective only against An. stephensi (31% mortality vs 3% in control-fed). Conclusions Ivermectin was not uniformly toxic to both Anopheles species. Previous studies indicate that ivermectin is a good choice of endectocide to use against malaria vectors in southeast Asia and Africa. However, these data suggest that ivermectin may not be the optimal endectocide to use in Central America or the Caribbean where An. albimanus is a major malaria vector species. If endectocides are to be used to help eradicate malaria, then additional efficacy data will be needed to define the activity of specific endectocides against the major malaria vector species of the world

Performance-based financing as a health system reform : mapping the key dimensions for monitoring and evaluation

Peer reviewedPublisher PD

Best practice for motor imagery: a systematic literature review on motor imagery training elements in five different disciplines

<p>Abstract</p> <p>Background</p> <p>The literature suggests a beneficial effect of motor imagery (MI) if combined with physical practice, but detailed descriptions of MI training session (MITS) elements and temporal parameters are lacking. The aim of this review was to identify the characteristics of a successful MITS and compare these for different disciplines, MI session types, task focus, age, gender and MI modification during intervention.</p> <p>Methods</p> <p>An extended systematic literature search using 24 databases was performed for five disciplines: Education, Medicine, Music, Psychology and Sports. References that described an MI intervention that focused on motor skills, performance or strength improvement were included. Information describing 17 MITS elements was extracted based on the PETTLEP (physical, environment, timing, task, learning, emotion, perspective) approach. Seven elements describing the MITS temporal parameters were calculated: study duration, intervention duration, MITS duration, total MITS count, MITS per week, MI trials per MITS and total MI training time.</p> <p>Results</p> <p>Both independent reviewers found 96% congruity, which was tested on a random sample of 20% of all references. After selection, 133 studies reporting 141 MI interventions were included. The locations of the MITS and position of the participants during MI were task-specific. Participants received acoustic detailed MI instructions, which were mostly standardised and live. During MI practice, participants kept their eyes closed. MI training was performed from an internal perspective with a kinaesthetic mode. Changes in MI content, duration and dosage were reported in 31 MI interventions. Familiarisation sessions before the start of the MI intervention were mentioned in 17 reports. MI interventions focused with decreasing relevance on motor-, cognitive- and strength-focused tasks. Average study intervention lasted 34 days, with participants practicing MI on average three times per week for 17 minutes, with 34 MI trials. Average total MI time was 178 minutes including 13 MITS. Reporting rate varied between 25.5% and 95.5%.</p> <p>Conclusions</p> <p>MITS elements of successful interventions were individual, supervised and non-directed sessions, added after physical practice. Successful design characteristics were dominant in the Psychology literature, in interventions focusing on motor and strength-related tasks, in interventions with participants aged 20 to 29 years old, and in MI interventions including participants of both genders. Systematic searching of the MI literature was constrained by the lack of a defined MeSH term.</p

A Meta-Synthesis of Disability Research in Western Africa

Most disability research is conducted in high-income countries, despite much of the world’s population living in low- and middle-income countries. Given the flexible nature of qualitative research, studies using this methodology have the potential to provide important insights into how disability is perceived across the globe. The aim of the current study was to synthesize the results of disability research in Western Africa to elucidate prominent themes and identify methodological and participant characteristics. Secondary purposes were to evaluate the quality of included studies. A total of 223 studies were included in this meta-synthesis. Findings reveal a diversity of disability-related themes and a need to increase transparency in reporting qualitative research. Implications and suggestions for future research are discussed

The Montreal Antenatal Well-Being Study (MAWS): a prospective longitudinal study of perinatal mental health.

Objective: This prospective longitudinal cohort aims to identify biological, psychological, and social factors that contribute to maternal perinatal mental health, family well-being, and child development. Method: Pregnant individuals (N=1130) were recruited between 8-20 gestation weeks. Questionnaire data were collected through a web-based platform together with biosamples for genetic analysis. Baseline characteristics of the cohort are described. A Bayesian model explored potential pandemic-associated changes in baseline maternal mental health symptoms throughout recruitment. Results: At baseline, 28.3% and 11.6% of pregnant participants reported clinically significant symptoms of anxiety (Spielberger Trait Anxiety Inventory ≥ 40) or depression (Edinburgh Postnatal Depression Scale ≥ 13). The onset of the COVID-19 pandemic was associated with increased likelihood of elevated scores on brief screening instruments for anxiety and depression. There was insufficient evidence for such effects using other screening tools. Conclusion(s): We further highlight anxiety and depression as common complications of pregnancy but find a modest impact of the pandemic on mental health within this cohort. Leveraging the unique data collected through this study we seek to inform screening practices and health policy to improve the well-being of mothers and families

Synthetic high-density lipoprotein nanoparticles for the treatment of Niemann–Pick diseases

Abstract Background Niemann–Pick disease type C is a fatal and progressive neurodegenerative disorder characterized by the accumulation of unesterified cholesterol in late endosomes and lysosomes. We sought to develop new therapeutics for this disorder by harnessing the body’s endogenous cholesterol scavenging particle, high-density lipoprotein (HDL). Methods Here we design, optimize, and define the mechanism of action of synthetic HDL (sHDL) nanoparticles. Results We demonstrate a dose-dependent rescue of cholesterol storage that is sensitive to sHDL lipid and peptide composition, enabling the identification of compounds with a range of therapeutic potency. Peripheral administration of sHDL to Npc1 I1061T homozygous mice mobilizes cholesterol, reduces serum bilirubin, reduces liver macrophage size, and corrects body weight deficits. Additionally, a single intraventricular injection into adult Npc1 I1061T brains significantly reduces cholesterol storage in Purkinje neurons. Since endogenous HDL is also a carrier of sphingomyelin, we tested the same sHDL formulation in the sphingomyelin storage disease Niemann–Pick type A. Utilizing stimulated Raman scattering microscopy to detect endogenous unlabeled lipids, we show significant rescue of Niemann–Pick type A lipid storage. Conclusions Together, our data establish that sHDL nanoparticles are a potential new therapeutic avenue for Niemann–Pick diseases.https://deepblue.lib.umich.edu/bitstream/2027.42/152143/1/12916_2019_Article_1423.pd