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1.
Parasit Vectors ; 17(1): 106, 2024 Mar 04.
Article in English | MEDLINE | ID: mdl-38439081

ABSTRACT

BACKGROUND: Although whole-genome sequencing (WGS) is the preferred genotyping method for most genomic analyses, limitations are often experienced when studying genomes characterized by a high percentage of repetitive elements, high linkage, and recombination deserts. The Asian tiger mosquito (Aedes albopictus), for example, has a genome comprising up to 72% repetitive elements, and therefore we set out to develop a single-nucleotide polymorphism (SNP) chip to be more cost-effective. Aedes albopictus is an invasive species originating from Southeast Asia that has recently spread around the world and is a vector for many human diseases. Developing an accessible genotyping platform is essential in advancing biological control methods and understanding the population dynamics of this pest species, with significant implications for public health. METHODS: We designed a SNP chip for Ae. albopictus (Aealbo chip) based on approximately 2.7 million SNPs identified using WGS data from 819 worldwide samples. We validated the chip using laboratory single-pair crosses, comparing technical replicates, and comparing genotypes of samples genotyped by WGS and the SNP chip. We then used the chip for a population genomic analysis of 237 samples from 28 sites in the native range to evaluate its usefulness in describing patterns of genomic variation and tracing the origins of invasions. RESULTS: Probes on the Aealbo chip targeted 175,396 SNPs in coding and non-coding regions across all three chromosomes, with a density of 102 SNPs per 1 Mb window, and at least one SNP in each of the 17,461 protein-coding genes. Overall, 70% of the probes captured the genetic variation. Segregation analysis found that 98% of the SNPs followed expectations of single-copy Mendelian genes. Comparisons with WGS indicated that sites with genotype disagreements were mostly heterozygotes at loci with WGS read depth < 20, while there was near complete agreement with WGS read depths > 20, indicating that the chip more accurately detects heterozygotes than low-coverage WGS. Sample sizes did not affect the accuracy of the SNP chip genotype calls. Ancestry analyses identified four to five genetic clusters in the native range with various levels of admixture. CONCLUSIONS: The Aealbo chip is highly accurate, is concordant with genotypes from WGS with high sequence coverage, and may be more accurate than low-coverage WGS.


Subject(s)
Aedes , Mosquito Vectors , Humans , Animals , Genotype , Mosquito Vectors/genetics , Heterozygote , Aedes/genetics
3.
Evol Appl ; 16(4): 849-862, 2023 Apr.
Article in English | MEDLINE | ID: mdl-37124090

ABSTRACT

The dengue mosquito, Aedes aegypti (Linnaeus, 1762), is a highly invasive and medically significant vector of dengue, yellow fever, chikungunya and Zika viruses, whose global spread can be attributed to increased globalization in the 15th through 20th century. Records of the invasion history of Ae. aegypti across Southeast Asia are sparse and there is little knowledge regarding the invasion routes that the species exploited to gain a foothold in the Indo-Pacific. Likewise, a broad and geographically thorough investigation of Ae. aegypti population genetics in the Indo-Pacific is lacking, despite this region being highly impacted by diseases transmitted by this species. We assess 11 nuclear microsatellites and mitochondrial COI sequences, coupled with widespread sampling through the Indo-Pacific region to characterise population structure at a broad geographic scale. We also perform a comprehensive literature search to collate documentation of the first known records of Ae. aegypti at various locations in the Indo-Pacific. We revealed additional spatial population genetic structure of Ae. aegypti in Southeast Asia, the Indo-Pacific and Australasia compared with previous studies and find differentiation between multiple Queensland and Torres Strait Islands populations. We also detected additional genetic breaks within Australia, Indonesia and Malaysia. Characterising the structure of previously unexplored populations through this region enhances the understanding of the population structure of Ae. aegypti in Australasia and Southeast Asia and may assist predictions of future mosquito movement, informing control strategies as well as assessing the risk of new invasion pathways.

4.
PLoS Negl Trop Dis ; 16(10): e0010786, 2022 10.
Article in English | MEDLINE | ID: mdl-36227923

ABSTRACT

Biological control of mosquito vectors using the endosymbiotic bacteria Wolbachia is an emerging strategy for the management of human arboviral diseases. We recently described the development of a strain of Aedes aegypti infected with the Wolbachia strain wAlbB (referred to as the wAlbB2-F4 strain) through simple backcrossing of wild type Australian mosquitoes with a wAlbB infected Ae. aegypti strain from the USA. Field releases of male wAlbB2-F4 mosquitoes resulted in the successful suppression of wild populations of mosquitoes in the trial sites by exploiting the strain's Wolbachia-induced cytoplasmic incompatibility. We now demonstrate that the strain is resistant to infection by dengue and Zika viruses and is genetically similar to endemic Queensland populations. There was a fourfold reduction in the proportion of wAlbB2-F4 mosquitoes that became infected following a blood meal containing dengue 2 virus (16.7%) compared to wild type mosquitoes (69.2%) and a 6-7 fold reduction in the proportion of wAlbB2-F4 mosquitoes producing virus in saliva following a blood meal containing an epidemic strain of Zika virus (8.7% in comparison to 58.3% in wild type mosquitoes). Restriction-site Associated DNA (RAD) sequencing revealed that wAlbB2-F4 mosquitoes have > 98% Australian ancestry, confirming the successful introduction of the wAlbB2 infection into the Australian genomic background through backcrossing. Genotypic and phenotypic analyses showed the wAlbB2-F4 strain retains the insecticide susceptible phenotype and genotype of native Australian mosquitoes. We demonstrate that the Wolbachia wAlbB2-F4, in addition to being suitable for population suppression programs, can also be effective in population replacement programs given its inhibition of virus infection in mosquitoes. The ease at which a target mosquito population can be transfected with wAlbB2, while retaining the genotypes and phenotypes of the target population, shows the utility of this strain for controlling the Ae. aegypti mosquitoes and the pathogens they transmit.


Subject(s)
Aedes , Dengue Virus , Dengue , Insecticides , Wolbachia , Zika Virus Infection , Zika Virus , Animals , Australia , DNA , Dengue/prevention & control , Dengue Virus/physiology , Humans , Male , Mosquito Vectors , Wolbachia/physiology , Zika Virus/genetics , Zika Virus Infection/prevention & control
5.
Proc Natl Acad Sci U S A ; 118(41)2021 10 12.
Article in English | MEDLINE | ID: mdl-34607949

ABSTRACT

Releasing sterile or incompatible male insects is a proven method of population management in agricultural systems with the potential to revolutionize mosquito control. Through a collaborative venture with the "Debug" Verily Life Sciences team, we assessed the incompatible insect technique (IIT) with the mosquito vector Aedes aegypti in northern Australia in a replicated treatment control field trial. Backcrossing a US strain of Ae. aegypti carrying Wolbachia wAlbB from Aedes albopictus with a local strain, we generated a wAlbB2-F4 strain incompatible with both the wild-type (no Wolbachia) and wMel-Wolbachia Ae. aegypti now extant in North Queensland. The wAlbB2-F4 strain was manually mass reared with males separated from females using Verily sex-sorting technologies to obtain no detectable female contamination in the field. With community consent, we delivered a total of three million IIT males into three isolated landscapes of over 200 houses each, releasing ∼50 males per house three times a week over 20 wk. Detecting initial overflooding ratios of between 5:1 and 10:1, strong population declines well beyond 80% were detected across all treatment landscapes when compared to controls. Monitoring through the following season to observe the ongoing effect saw one treatment landscape devoid of adult Ae. aegypti early in the season. A second landscape showed reduced adults, and the third recovered fully. These encouraging results in suppressing both wild-type and wMel-Ae. aegypti confirms the utility of bidirectional incompatibility in the field setting, show the IIT to be robust, and indicate that the removal of this arbovirus vector from human-occupied landscapes may be achievable.


Subject(s)
Aedes/microbiology , Arbovirus Infections/prevention & control , Infertility, Male , Mosquito Control/methods , Wolbachia/metabolism , Aedes/physiology , Animals , Arbovirus Infections/transmission , Arboviruses , Australia , Biological Control Agents , Female , Humans , Male , Mosquito Vectors/microbiology , Queensland
6.
NanoImpact ; 22: 100320, 2021 04.
Article in English | MEDLINE | ID: mdl-35559977

ABSTRACT

As businesses, specifically technology developers and industrial suppliers, strive to meet growing demand for higher quality drinking water, the use of engineered nanomaterials in commercial point-of-use (POU) in-home water purification devices are becoming an increasingly important option. Anecdotally, some businesses appear wary of developing and marketing nanomaterial-enabled devices because of concerns that they will face onerous regulation and consumer pushback. However, little of substance is known about business perceptions of and attitudes toward the use of engineered nanomaterials in POU water purification devices, or how these compare with consumer perceptions. To address this knowledge-gap, we administered a 14-question survey among 65 participants from US-based industrial companies focused on drinking water purification. Our results indicate that the dominant concerns for businesses are costs and public perceptions associated with nanomaterial-enabled POU devices for drinking water purification. Cost-specific barriers include competition from more conventional technologies, and tensions between operational versus capital costs. 57% of respondents were concerned or very concerned that public perceptions will influence the long-term viability of nanomaterial-enabled POU devices for drinking water purification. 49% of respondents stated that government regulation of nanomaterials would be the preferred approach to ensure public safety, followed by the certification of POU devices (28%). When asked about specific nanomaterials and their potential use in POU devices for drinking water purification, respondents ranked carbon nanotubes as the nanomaterial with highest concern for environmental health and safety, followed by silver, titanium dioxide, zinc oxide, and copper. Respondents ranked nanoclays as the nanomaterial with highest likelihood for public acceptance, followed by silica, cerium oxide, titanium dioxide, and aluminum oxide.


Subject(s)
Drinking Water , Nanostructures , Nanotubes, Carbon , Water Purification , Humans , Surveys and Questionnaires , Water Purification/methods
7.
J Med Internet Res ; 21(10): e16321, 2019 10 31.
Article in English | MEDLINE | ID: mdl-31674917

ABSTRACT

Advanced brain machine interfaces provide potentially transformative approaches to treating neurological conditions and enhancing the performance of users. Yet, as technological capabilities continue to progress in leaps and bounds, there is a possibility that these capabilities outstrip our collective understanding of how to ensure brain machine interfaces are developed and used ethically and responsibly. In this case, there is an overt danger of rapid technological developments leading to unanticipated harm through a lack of foresight including threats to privacy, autonomy, self-identity, and other areas of personal and social value which, while hard to quantify, represent substantial risks. There is also a very real likelihood of such risks undermining value creation around the technologies and the associated enterprises, as key stakeholders push back against perceived and actual threats to what they, in turn, hold to be of value. In order to successfully traverse the resulting risk landscape, researchers and developers will need to become increasingly adept at integrating a sophisticated understanding of ethical and socially responsible innovation into their enterprises. Here, we illustrate how a "risk innovation" approach may provide novel insights into mapping out this landscape and revealing potentially blindsiding risks. We show how this approach can be used to illuminate challenges and opportunities to the successful, ethical, and responsible development of advanced brain machine interfaces. In addition, we emphasize how success will ultimately depend on the willingness of innovators and others to take ethical and responsible innovation seriously and to draw on the interdisciplinary and transdisciplinary expertise that is necessary to translate good intentions into positive outcomes.


Subject(s)
Brain-Computer Interfaces , Humans , Privacy , Research Personnel , Technology
9.
Sci Rep ; 8(1): 10779, 2018 Jul 17.
Article in English | MEDLINE | ID: mdl-30018450

ABSTRACT

Kabuki Syndrome (KS) is a rare disorder characterized by distinctive facial features, short stature, skeletal abnormalities, and neurodevelopmental deficits. Previously, we showed that loss of function of RAP1A, a RAF1 regulator, can activate the RAS/MAPK pathway and cause KS, an observation recapitulated in other genetic models of the disorder. These data suggested that suppression of this signaling cascade might be of therapeutic benefit for some features of KS. To pursue this possibility, we performed a focused small molecule screen of a series of RAS/MAPK pathway inhibitors, where we tested their ability to rescue disease-relevant phenotypes in a zebrafish model of the most common KS locus, kmt2d. Consistent with a pathway-driven screening paradigm, two of 27 compounds showed reproducible rescue of early developmental pathologies. Further analyses showed that one compound, desmethyl-Dabrafenib (dmDf), induced no overt pathologies in zebrafish embryos but could rescue MEK hyperactivation in vivo and, concomitantly, structural KS-relevant phenotypes in all KS zebrafish models (kmt2d, kmd6a and rap1). Mass spectrometry quantitation suggested that a 100 nM dose resulted in sub-nanomolar exposure of this inhibitor and was sufficient to rescue both mandibular and neurodevelopmental defects. Crucially, germline kmt2d mutants recapitulated the gastrulation movement defects, micrognathia and neurogenesis phenotypes of transient models; treatment with dmDf ameliorated all of them significantly. Taken together, our data reinforce a causal link between MEK hyperactivation and KS and suggest that chemical suppression of BRAF might be of potential clinical utility for some features of this disorder.


Subject(s)
Abnormalities, Multiple/prevention & control , Face/abnormalities , Hematologic Diseases/prevention & control , Imidazoles/pharmacology , Oximes/pharmacology , Protein Kinase Inhibitors/pharmacology , Vestibular Diseases/prevention & control , Zebrafish/growth & development , Abnormalities, Multiple/pathology , Animals , Craniofacial Abnormalities/prevention & control , Face/pathology , Hematologic Diseases/pathology , Imidazoles/adverse effects , Imidazoles/chemistry , Jaw Abnormalities/prevention & control , MAP Kinase Signaling System , Oximes/adverse effects , Oximes/chemistry , Proto-Oncogene Proteins p21(ras)/metabolism , Toxicity Tests , Vestibular Diseases/pathology , Zebrafish/embryology , Zebrafish/genetics
11.
SAGE Open Med Case Rep ; 5: 2050313X17713912, 2017.
Article in English | MEDLINE | ID: mdl-28634542

ABSTRACT

OBJECTIVE: To describe the perioperative management of a patient with acquired angioedema (AAE). METHODS: A 66-year-old Caucasian male presented from an outside hospital with a history of acquired angioedema and gastrointestinal stromal tumor-related intractable urticaria and mastocytosis. He was admitted for urgent laparoscopic partial gastrectomy, secondary to gastric outlet obstruction symptomatology. Previous combined attacks were characterized by a widespread rash, abdominal pain and respiratory distress resulting in hospitalization. Following preoperative consultation with the patient's allergist and a hospital pharmacist, he was treated preoperatively with fresh frozen plasma and his home prednisone dose. C1-inhibitor (Berinert®) was on standby along with epinephrine, given that the underlying etiology (C1- inhibitor deficiency vs histaminergic) was not known. RESULTS: There were no intraoperative complications, and the patient was discharged home 3 days after the procedure. CONCLUSIONS: Optimization of perioperative outcomes in patients, especially during urgent or emergent surgery, with a history of angioedema requires the development of a patient-specific perioperative plan, including prophylaxis, rescue therapies and opioid-sparing strategies.

12.
PLoS Negl Trop Dis ; 11(4): e0005546, 2017 04.
Article in English | MEDLINE | ID: mdl-28410388

ABSTRACT

BACKGROUND: Within the last century, increases in human movement and globalization of trade have facilitated the establishment of several highly invasive mosquito species in new geographic locations with concurrent major environmental, economic and health consequences. The Asian tiger mosquito, Aedes albopictus, is an extremely invasive and aggressive daytime-biting mosquito that is a major public health threat throughout its expanding range. METHODOLOGY/PRINCIPAL FINDINGS: We used 13 nuclear microsatellite loci (on 911 individuals) and mitochondrial COI sequences to gain a better understanding of the historical and contemporary movements of Ae. albopictus in the Indo-Pacific region and to characterize its population structure. Approximate Bayesian computation (ABC) was employed to test competing historical routes of invasion of Ae. albopictus within the Southeast (SE) Asian/Australasian region. Our ABC results show that Ae. albopictus was most likely introduced to New Guinea via mainland Southeast Asia, before colonizing the Solomon Islands via either Papua New Guinea or SE Asia. The analysis also supported that the recent incursion into northern Australia's Torres Strait Islands was seeded chiefly from Indonesia. For the first time documented in this invasive species, we provide evidence of a recently colonized population (the Torres Strait Islands) that has undergone rapid temporal changes in its genetic makeup, which could be the result of genetic drift or represent a secondary invasion from an unknown source. CONCLUSIONS/SIGNIFICANCE: There appears to be high spatial genetic structure and high gene flow between some geographically distant populations. The species' genetic structure in the region tends to favour a dispersal pattern driven mostly by human movements. Importantly, this study provides a more widespread sampling distribution of the species' native range, revealing more spatial population structure than previously shown. Additionally, we present the most probable invasion history of this species in the Australasian region using ABC analysis.


Subject(s)
Aedes/classification , Aedes/growth & development , Genetic Variation , Aedes/genetics , Animals , Asia, Southeastern , Australasia , Electron Transport Complex IV/genetics , Indonesia , Microsatellite Repeats , Pacific Islands , Sequence Analysis, DNA , Spatio-Temporal Analysis
13.
J Dev Behav Pediatr ; 38(2): 155-160, 2017.
Article in English | MEDLINE | ID: mdl-27984419

ABSTRACT

: Family functioning is associated with obesity-related chronic illnesses and impedes effective treatment of weight-related conditions, such as nonalcoholic fatty liver disease (NAFLD). OBJECTIVES: Evaluate the utility of a brief screening measure of family functioning among youth aged 8 to 18 years being treated in a specialty care clinic for NAFLD. METHODS: Thirty-nine youths and their caregivers participated. Relations between family functioning and anthropometric and biochemical variables assessed 3 to 6 months later were evaluated using regression analyses, controlling for child age, gender, and ethnicity. RESULTS: Family functioning was related to significantly higher body mass index (BMI) and levels of cholesterol, HbA1c, and glucose, but not serum alanine aminotransferase (ALT)-a marker of NAFLD-controlling for baseline levels. The magnitudes of effects were medium for models of BMI (Cohen's f = 0.29), cholesterol (0.32), and blood glucose (0.30) and small to medium for HbA1c (0.23) and ALT (0.10). CONCLUSION: This is the first study to examine the role of family functioning in youth with NALFD. Treatment programs might consider screening for family functioning to identify families that could benefit from a family-centered behavioral intervention.


Subject(s)
Blood Glucose , Body Mass Index , Cholesterol/blood , Family Relations , Glycated Hemoglobin , Non-alcoholic Fatty Liver Disease/blood , Adolescent , Child , Female , Humans , Male
14.
Nat Nanotechnol ; 11(12): 998-1000, 2016 Dec 06.
Article in English | MEDLINE | ID: mdl-27920442
15.
Nat Nanotechnol ; 11(9): 734-5, 2016 09 07.
Article in English | MEDLINE | ID: mdl-27599878
16.
Nat Nanotechnol ; 11(6): 490-491, 2016 06 07.
Article in English | MEDLINE | ID: mdl-27272137
17.
Article in English | MEDLINE | ID: mdl-27030583

ABSTRACT

Infertility and adverse pregnancy outcomes are significant public health concerns with global prevalence. Over the past 35 years, research has addressed whether exposure to power-frequency magnetic fields is one of the etiologic factors attributed to these conditions. However, no apparent authoritative reviews on this topic have been published in the peer-reviewed literature for nearly 15 years. This review provides an overview and critical analysis of human studies that were published in the peer-reviewed literature between 2002 and July 2015. Using PubMed, 13 epidemiology studies published during this time frame that concern exposure to magnetic fields and adverse prenatal (e.g., miscarriage), neonatal (e.g., preterm birth or birth defects), and male fertility (e.g., poor semen quality) outcomes were identified. Some of these studies reported associations whereas others did not, and study design limitations may explain these inconsistencies. Future investigations need to be designed with these limitations in mind to address existing research gaps. In particular, the following issues are discussed: (1) importance of selecting the appropriate study population, (2) need for addressing confounding due to unmeasured physical activity, (3) importance of minimizing information bias from exposure measurement error, (4) consideration of alternative magnetic field exposure metrics, and (5) implications and applications of personal exposure data that are correlated within female-male couples. Further epidemiologic research is needed, given the near ubiquitous exposures to power-frequency magnetic fields in the general population.


Subject(s)
Environmental Exposure/adverse effects , Fetal Development/radiation effects , Infertility/etiology , Magnetic Fields/adverse effects , Pregnancy Outcome , Female , Humans , Infant, Newborn , Male , Pregnancy , Prenatal Exposure Delayed Effects , Research Design , Risk
19.
Environ Sci Nano ; 3(6): 1510-1520, 2016 Dec 01.
Article in English | MEDLINE | ID: mdl-28357114

ABSTRACT

Due to their widespread incorporation into a range of biomedical and consumer products, the ingestion of silver nanoparticles (AgNPs) is of considerable concern to human health. However, the extent to which AgNPs will be modified within the gastric compartment of the gastrointestinal tract is still poorly understood. Studies have yet to fully evaluate the extent of physicochemical changes to AgNPs in the presence of biological macromolecules, such as pepsin, the most abundant protein in the stomach, or the influence of AgNPs on protein structure and activity. Herein, AgNPs of two different sizes and surface coatings (20 and 110 nm, citrate or polyvinylpyrrolidone) were added to simulated gastric fluid (SGF) with or without porcine pepsin at three pHs (2.0, 3.5, and 5.0), representing a range of values between preprandial (fasted) and postprandial (fed) conditions. Rapid increases in diameter were observed for all AgNPs, with a greater increase in diameter in the presence of pepsin, indicating that pepsin facilitated AgNPs aggregation. AgNPs interaction with pepsin only minimally reduced the protein's proteolytic functioning capability, with the greatest inhibitory effect caused by smaller (20 nm) particles of both coatings. No changes in pepsin secondary structural elements were observed for the different AgNPs, even at high particle concentrations. This research highlights the size-dependent kinetics of nanoparticle aggregation or dissolution from interaction with biological elements such as proteins in the gastrointestinal tract. Further, these results demonstrate that, in addition to mass, knowing the chemical form and aggregation state of nanoparticles is critical when evaluating toxicological effects from nanoparticle exposure in the body.

20.
J Law Med Ethics ; 44(4): 657-659, 2016 12.
Article in English | MEDLINE | ID: mdl-28661244

ABSTRACT

Zika infection in pregnant women is associated with an elevated probability of giving birth to a child with microcephaly and multiple other disabilities. Public health messaging on Zika prevention has predominantly targeted women who know they are pregnant or intend to become pregnant, but not teenage females for whom unintended pregnancy is more likely. Vulnerabilities among this population to reproductive risks associated with Zika are further amplified by restrictive abortion laws in several Zika-impacted states. Key to prevention is enhanced, targeted public health messaging centered on teens nationally and particularly in certain high-risk regions.


Subject(s)
Pregnancy Complications, Infectious/prevention & control , Pregnancy in Adolescence , Zika Virus Infection/prevention & control , Adolescent , Female , Humans , Pregnancy , Pregnant Women , Public Health , Zika Virus
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