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1.
Viruses ; 15(4)2023 03 26.
Article in English | MEDLINE | ID: mdl-37112832

ABSTRACT

Dengue transmission is determined by a complex set of interactions between the environment, Aedes aegypti mosquitoes, dengue viruses, and humans. Emergence in new geographic areas can be unpredictable, with some regions having established mosquito populations for decades without locally acquired transmission. Key factors such as mosquito longevity, temperature-driven extrinsic incubation period (EIP), and vector-human contact can strongly influence the potential for disease transmission. To assess how these factors interact at the edge of the geographical range of dengue virus transmission, we conducted mosquito sampling in multiple urban areas located throughout the Arizona-Sonora desert region during the summer rainy seasons from 2013 to 2015. Mosquito population age structure, reflecting mosquito survivorship, was measured using a combination of parity analysis and relative gene expression of an age-related gene, SCP-1. Bloodmeal analysis was conducted on field collected blood-fed mosquitoes. Site-specific temperature was used to estimate the EIP, and this predicted EIP combined with mosquito age were combined to estimate the abundance of "potential" vectors (i.e., mosquitoes old enough to survive the EIP). Comparisons were made across cities by month and year. The dengue endemic cities Hermosillo and Ciudad Obregon, both in the state of Sonora, Mexico, had higher abundance of potential vectors than non-endemic Nogales, Sonora, Mexico. Interestingly, Tucson, Arizona consistently had a higher estimated abundance of potential vectors than dengue endemic regions of Sonora, Mexico. There were no observed city-level differences in species composition of blood meals. Combined, these data offer insights into the critical factors required for dengue transmission at the ecological edge of the mosquito's range. However, further research is needed to integrate an understanding of how social and additional environmental factors constrain and enhance dengue transmission in emerging regions.


Subject(s)
Aedes , Dengue Virus , Dengue , Animals , Humans , Arizona/epidemiology , Temperature , Mosquito Vectors , Infectious Disease Incubation Period
2.
BMC Med ; 20(1): 293, 2022 09 07.
Article in English | MEDLINE | ID: mdl-36068517

ABSTRACT

BACKGROUND: Onchocerciasis is a disease caused by infection with Onchocerca volvulus, which is transmitted to humans via the bite of several species of black fly, and is responsible for permanent blindness or vision loss, as well as severe skin disease. Predominantly endemic in parts of Africa and Yemen, preventive chemotherapy with mass drug administration of ivermectin is the primary intervention recommended for the elimination of its transmission. METHODS: A dataset of 18,116 geo-referenced prevalence survey datapoints was used to model annual 2000-2018 infection prevalence in Africa and Yemen. Using Bayesian model-based geostatistics, we generated spatially continuous estimates of all-age 2000-2018 onchocerciasis infection prevalence at the 5 × 5-km resolution as well as aggregations to the national level, along with corresponding estimates of the uncertainty in these predictions. RESULTS: As of 2018, the prevalence of onchocerciasis infection continues to be concentrated across central and western Africa, with the highest mean estimates at the national level in Ghana (12.2%, 95% uncertainty interval [UI] 5.0-22.7). Mean estimates exceed 5% infection prevalence at the national level for Cameroon, Central African Republic, Democratic Republic of the Congo (DRC), Guinea-Bissau, Sierra Leone, and South Sudan. CONCLUSIONS: Our analysis suggests that onchocerciasis infection has declined over the last two decades throughout western and central Africa. Focal areas of Angola, Cameroon, the Democratic Republic of the Congo, Ethiopia, Ghana, Guinea, Mali, Nigeria, South Sudan, and Uganda continue to have mean microfiladermia prevalence estimates exceeding 25%. At and above this level, the continuation or initiation of mass drug administration with ivermectin is supported. If national programs aim to eliminate onchocerciasis infection, additional surveillance or supervision of areas of predicted high prevalence would be warranted to ensure sufficiently high coverage of program interventions.


Subject(s)
Onchocerciasis , Bayes Theorem , Ghana , Humans , Ivermectin/therapeutic use , Nigeria , Onchocerciasis/drug therapy , Onchocerciasis/epidemiology , Onchocerciasis/prevention & control , Prevalence , Yemen/epidemiology
3.
PLoS Negl Trop Dis ; 15(7): e0008824, 2021 07.
Article in English | MEDLINE | ID: mdl-34319976

ABSTRACT

Recent evidence suggests that, in some foci, elimination of onchocerciasis from Africa may be feasible with mass drug administration (MDA) of ivermectin. To achieve continental elimination of transmission, mapping surveys will need to be conducted across all implementation units (IUs) for which endemicity status is currently unknown. Using boosted regression tree models with optimised hyperparameter selection, we estimated environmental suitability for onchocerciasis at the 5 × 5-km resolution across Africa. In order to classify IUs that include locations that are environmentally suitable, we used receiver operating characteristic (ROC) analysis to identify an optimal threshold for suitability concordant with locations where onchocerciasis has been previously detected. This threshold value was then used to classify IUs (more suitable or less suitable) based on the location within the IU with the largest mean prediction. Mean estimates of environmental suitability suggest large areas across West and Central Africa, as well as focal areas of East Africa, are suitable for onchocerciasis transmission, consistent with the presence of current control and elimination of transmission efforts. The ROC analysis identified a mean environmental suitability index of 0·71 as a threshold to classify based on the location with the largest mean prediction within the IU. Of the IUs considered for mapping surveys, 50·2% exceed this threshold for suitability in at least one 5 × 5-km location. The formidable scale of data collection required to map onchocerciasis endemicity across the African continent presents an opportunity to use spatial data to identify areas likely to be suitable for onchocerciasis transmission. National onchocerciasis elimination programmes may wish to consider prioritising these IUs for mapping surveys as human resources, laboratory capacity, and programmatic schedules may constrain survey implementation, and possibly delaying MDA initiation in areas that would ultimately qualify.


Subject(s)
Disease Eradication , Onchocerciasis/epidemiology , Africa/epidemiology , Environment , Forecasting , Humans , Ivermectin/administration & dosage , Mass Drug Administration , Onchocerciasis/drug therapy , Onchocerciasis/transmission , ROC Curve
4.
Nat Commun ; 11(1): 2408, 2020 05 15.
Article in English | MEDLINE | ID: mdl-32415113

ABSTRACT

Uveal melanoma (UM) is the most common intraocular tumour in adults and despite surgical or radiation treatment of primary tumours, ~50% of patients progress to metastatic disease. Therapeutic options for metastatic UM are limited, with clinical trials having little impact. Here we perform whole-genome sequencing (WGS) of 103 UM from all sites of the uveal tract (choroid, ciliary body, iris). While most UM have low tumour mutation burden (TMB), two subsets with high TMB are seen; one driven by germline MBD4 mutation, and another by ultraviolet radiation (UVR) exposure, which is restricted to iris UM. All but one tumour have a known UM driver gene mutation (GNAQ, GNA11, BAP1, PLCB4, CYSLTR2, SF3B1, EIF1AX). We identify three other significantly mutated genes (TP53, RPL5 and CENPE).


Subject(s)
Iris Neoplasms/genetics , Iris Neoplasms/pathology , Melanoma/genetics , Melanoma/pathology , Uveal Neoplasms/genetics , Uveal Neoplasms/pathology , Cell Line, Tumor , Chromosome Aberrations , Computational Biology , DNA Mutational Analysis , Disease Progression , Disease-Free Survival , Gene Dosage , Genome, Human , Genomics , Humans , Kaplan-Meier Estimate , Markov Chains , Melanocytes/metabolism , Mutation , Phenotype , Prognosis , Tumor Suppressor Protein p53/genetics , Ultraviolet Rays
5.
Parasit Vectors ; 11(1): 267, 2018 Apr 25.
Article in English | MEDLINE | ID: mdl-29695282

ABSTRACT

BACKGROUND: Transmission dynamics of mosquito-borne viruses such as dengue, Zika and chikungunya are affected by the longevity of the adult female mosquito. Environmental conditions influence the survival of adult female Aedes mosquitoes, the primary vectors of these viruses. While the association of temperature with Aedes mortality has been relatively well-explored, the role of humidity is less established. The current study's goals were to compile knowledge of the influence of humidity on adult survival in the important vector species Aedes aegypti and Ae. albopictus, and to quantify this relationship while accounting for the modifying effect of temperature. METHODS: We performed a systematic literature review to identify studies reporting experimental results informing the relationships among temperature, humidity and adult survival in Ae. aegypti and Ae. albopictus. Using a novel simulation approach to harmonize disparate survival data, we conducted pooled survival analyses via stratified and mixed effects Cox regression to estimate temperature-dependent associations between humidity and mortality risk for these species across a broad range of temperatures and vapor pressure deficits. RESULTS: After screening 1517 articles, 17 studies (one in semi-field and 16 in laboratory settings) met inclusion criteria and collectively reported results for 192 survival experiments. We review and synthesize relevant findings from these studies. Our stratified model estimated a strong temperature-dependent association of humidity with mortality in both species, though associations were not significant for Ae. albopictus in the mixed effects model. Lowest mortality risks were estimated around 27.5 °C and 21.5 °C for Ae. aegypti and Ae. albopictus, respectively, and mortality increased non-linearly with decreasing humidity. Aedes aegypti had a survival advantage relative to Ae. albopictus in the stratified model under most conditions, but species differences were not significant in the mixed effects model. CONCLUSIONS: Humidity is associated with mortality risk in adult female Ae. aegypti in controlled settings. Data are limited at low humidities, temperature extremes, and for Ae. albopictus, and further studies should be conducted to reduce model uncertainty in these contexts. Desiccation is likely an important factor in Aedes population dynamics and viral transmission in arid regions. Models of Aedes-borne virus transmission may be improved by more comprehensively representing humidity effects.


Subject(s)
Aedes/physiology , Longevity , Mosquito Vectors/physiology , Stress, Physiological , Animals , Female , Humidity , Survival Analysis , Temperature
6.
JMIR Mhealth Uhealth ; 5(10): e142, 2017 Oct 09.
Article in English | MEDLINE | ID: mdl-28993302

ABSTRACT

BACKGROUND: The See Me Smoke-Free (SMSF) mobile health (mHealth) app was developed to help women quit smoking by targeting concerns about body weight, body image, and self-efficacy through cognitive behavioral techniques and guided imagery audio files addressing smoking, diet, and physical activity. A feasibility trial found associations between SMSF usage and positive treatment outcomes. This paper reports a detailed exploration of program use among eligible individuals consenting to study participation and completing the baseline survey (participants) and ineligible or nonconsenting app installers (nonparticipants), as well as the relationship between program use and treatment outcomes. OBJECTIVE: The aim of this study was to determine whether (1) participants were more likely to set quit dates, be current smokers, and report higher levels of smoking at baseline than nonparticipants; (2) participants opened the app and listened to audio files more frequently than nonparticipants; and (3) participants with more app usage had a higher likelihood of self-reported smoking abstinence at follow up. METHODS: The SMSF feasibility trial was a single arm, within-subjects, prospective cohort study with assessments at baseline and 30 and 90 days post enrollment. The SMSF app was deployed on the Google Play Store for download, and basic profile characteristics were obtained for all app installers. Additional variables were assessed for study participants. Participants were prompted to use the app daily during study participation. Crude differences in baseline characteristics between trial participants and nonparticipants were evaluated using t tests (continuous variables) and Fisher exact tests (categorical variables). Exact Poisson tests were used to assess group-level differences in mean usage rates over the full study period using aggregate Google Analytics data on participation and usage. Negative binomial regression models were used to estimate associations of app usage with participant baseline characteristics after adjustment for putative confounders. Associations between app usage and self-reported smoking abstinence were assessed using separate logistic regression models for each outcome measure. RESULTS: Participants (n=151) were more likely than nonparticipants (n=96) to report female gender (P<.02) and smoking in the 30 days before enrollment (P<.001). Participants and nonparticipants opened the app and updated quit dates at the same average rate (rate ratio [RR] 0.98; 95% CI 0.92-1.04; P=.43), but participants started audio files (RR 1.07; 95% CI 1.00-1.13; P<.04) and completed audio files (RR 1.11; 95% CI 1.03-1.18; P<.003) at significantly higher rates than nonparticipants. Higher app usage among participants was positively associated with some smoking cessation outcomes. CONCLUSIONS: This study suggests potential efficacy of the SMSF app, as increased usage was generally associated with higher self-reported smoking abstinence. A planned randomized controlled trial will assess the SMSF app's efficacy as an intervention tool to help women quit smoking.

7.
Science ; 357(6350): 512-515, 2017 08 04.
Article in English | MEDLINE | ID: mdl-28774930

ABSTRACT

By 4000 years ago, people had introduced maize to the southwestern United States; full agriculture was established quickly in the lowland deserts but delayed in the temperate highlands for 2000 years. We test if the earliest upland maize was adapted for early flowering, a characteristic of modern temperate maize. We sequenced fifteen 1900-year-old maize cobs from Turkey Pen Shelter in the temperate Southwest. Indirectly validated genomic models predicted that Turkey Pen maize was marginally adapted with respect to flowering, as well as short, tillering, and segregating for yellow kernel color. Temperate adaptation drove modern population differentiation and was selected in situ from ancient standing variation. Validated prediction of polygenic traits improves our understanding of ancient phenotypes and the dynamics of environmental adaptation.


Subject(s)
Acclimatization/genetics , Zea mays/genetics , Zea mays/physiology , Cold Temperature , Flowers/genetics , Flowers/physiology , Genome, Plant , Genomics , Multifactorial Inheritance , North America , Phenotype
8.
Mol Phylogenet Evol ; 103: 143-154, 2016 10.
Article in English | MEDLINE | ID: mdl-27450781

ABSTRACT

Ants in the genera Anochetus and Odontomachus belong to one of the largest clades in the subfamily Ponerinae, and are one of four lineages of ants possessing spring-loaded "trap-jaws." Here we present results from the first global species-level molecular phylogenetic analysis of these trap-jaw ants, reconstructed from one mitochondrial, one ribosomal RNA, and three nuclear protein-coding genes. Bayesian and likelihood analyses strongly support reciprocal monophyly for the genera Anochetus and Odontomachus. Additionally, we found strong support for seven trap-jaw ant clades (four in Anochetus and three in Odontomachus) mostly concordant with geographic distribution. Ambiguity remains concerning the closest living non-trap-jaw ant relative of the Anochetus+Odontomachus clade, but Bayes factor hypothesis testing strongly suggests that trap-jaw ants evolved from a short mandible ancestor. Ponerine trap-jaw ants originated in the early Eocene (52.5Mya) in either South America or Southeast Asia, where they have radiated rapidly in the last 30million years, and subsequently dispersed multiple times to Africa and Australia. These results will guide future taxonomic work on the group and act as a phylogenetic framework to study the macroevolution of extreme ant mouthpart specialization.


Subject(s)
Ants/classification , Africa , Animals , Ants/genetics , Asia, Southeastern , Australia , Bayes Theorem , Cytochromes b/classification , Cytochromes b/genetics , Cytochromes b/metabolism , Genetic Variation , Phylogeny , Phylogeography , RNA, Ribosomal, 28S/classification , RNA, Ribosomal, 28S/genetics , RNA, Ribosomal, 28S/metabolism , South America
9.
PLoS Curr ; 82016 Mar 16.
Article in English | MEDLINE | ID: mdl-27066299

ABSTRACT

INTRODUCTION: An ongoing Zika virus pandemic in Latin America and the Caribbean has raised concerns that travel-related introduction of Zika virus could initiate local transmission in the United States (U.S.) by its primary vector, the mosquito Aedes aegypti. METHODS: We employed meteorologically driven models for 2006-2015 to simulate the potential seasonal abundance of adult Aedes aegypti for fifty cities within or near the margins of its known U.S. range. Mosquito abundance results were analyzed alongside travel and socioeconomic factors that are proxies of viral introduction and vulnerability to human-vector contact.     RESULTS: Meteorological conditions are largely unsuitable for Aedes aegypti over the U.S. during winter months (December-March), except in southern Florida and south Texas where comparatively warm conditions can sustain low-to-moderate potential mosquito abundance. Meteorological conditions are suitable for Aedes aegypti across all fifty cities during peak summer months (July-September), though the mosquito has not been documented in all cities. Simulations indicate the highest mosquito abundance occurs in the Southeast and south Texas where locally acquired cases of Aedes-transmitted viruses have been reported previously. Cities in southern Florida and south Texas are at the nexus of high seasonal suitability for Aedes aegypti and strong potential for travel-related virus introduction. Higher poverty rates in cities along the U.S.-Mexico border may correlate with factors that increase human exposure to Aedes aegypti.     DISCUSSION: Our results can inform baseline risk for local Zika virus transmission in the U.S. and the optimal timing of vector control activities, and underscore the need for enhanced surveillance for Aedes mosquitoes and Aedes-transmitted viruses.

10.
Zygote ; 24(2): 266-76, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26099992

ABSTRACT

Thyroid hormones (THs) have been shown to improve in vitro embryo production in cattle by increasing blastocyst formation rate, and the average cell number of blastocysts and by significantly decreasing apoptosis rate. To better understand those genetic aspects that may underlie enhanced early embryo development in the presence of THs, we characterized the bovine embryonic transcriptome at the blastocyst stage, and examined differential gene expression profiles using a bovine-specific microarray. We found that 1212 genes were differentially expressed in TH-treated embryos when compared with non-treated controls (>1.5-fold at P < 0.05). In addition 23 and eight genes were expressed uniquely in control and treated embryos, respectively. The expression of genes specifically associated with metabolism, mitochondrial function, cell differentiation and development were elevated. However, TH-related genes, including those encoding TH receptors and deiodinases, were not differentially expressed in treated embryos. Furthermore, the over-expression of 52 X-chromosome linked genes in treated embryos suggested a delay or escape from X-inactivation. This study highlights the significant impact of THs on differential gene expression in the early embryo; the identification of TH-responsive genes provides an insight into those regulatory pathways activated during development.


Subject(s)
Blastocyst/drug effects , Gene Expression Regulation, Developmental/drug effects , Thyroid Hormones/pharmacology , Transcriptome/drug effects , Animals , Blastocyst/cytology , Blastocyst/metabolism , Cattle , Embryonic Development/drug effects , Embryonic Development/genetics , Female , Fertilization in Vitro/methods , Fertilization in Vitro/veterinary , Gene Expression Profiling/methods , Gene Expression Profiling/veterinary , Male , Oligonucleotide Array Sequence Analysis/methods , Oligonucleotide Array Sequence Analysis/veterinary , Reproducibility of Results , Reverse Transcriptase Polymerase Chain Reaction/methods , Reverse Transcriptase Polymerase Chain Reaction/veterinary
11.
Pigment Cell Melanoma Res ; 28(3): 281-94, 2015 May.
Article in English | MEDLINE | ID: mdl-25645385

ABSTRACT

Advancements in high-resolution HPLC and mass spectrometry have reinvigorated the application of this technology to identify peptides eluted from immunopurified MHC class I molecules. Three melanoma cell lines were assessed using w6/32 isolation, peptide elution and HPLC purification; peptides were identified by mass spectrometry. A total of 13,829 peptides were identified; 83-87% of these were 8-11 mers. Only approximately 15% have been described before. Subcellular locations of the source proteins showed even sampling; mRNA expression and total protein length were predictive of the number of peptides detected from a single protein. HLA-type binding prediction for 10,078 9/10 mer peptides assigned 88-95% to a patient-specific HLA subtype, revealing a disparity in strength of predicted binding. HLA-B*27-specific isolation successfully identified some peptides not found using w6/32. Sixty peptides were selected for immune screening, based on source protein and predicted HLA binding; no new peptides recognized by antimelanoma T cells were discovered. Additionally, mass spectrometry was unable to identify several epitopes targeted ex vivo by one patient's T cells.


Subject(s)
Histocompatibility Antigens Class I/metabolism , Melanoma/immunology , Peptides/metabolism , Algorithms , Amino Acid Sequence , Antibodies/metabolism , Antigens, Neoplasm/metabolism , Cell Line, Tumor , Epitopes , Gene Expression Regulation, Neoplastic , Humans , Immunity , Mass Spectrometry , Melanoma/genetics , Molecular Sequence Data , Peptides/chemistry , Peptides/isolation & purification , Protein Binding , Protein Processing, Post-Translational , RNA, Messenger/genetics , RNA, Messenger/metabolism , Reproducibility of Results , Subcellular Fractions/metabolism
12.
BMC Bioinformatics ; 14: 302, 2013 Oct 07.
Article in English | MEDLINE | ID: mdl-24098943

ABSTRACT

BACKGROUND: Residual Dipolar Couplings (RDCs) have emerged in the past two decades as an informative source of experimental restraints for the study of structure and dynamics of biological macromolecules and complexes. The REDCAT software package was previously introduced for the analysis of molecular structures using RDC data. Here we report additional features that have been included in this software package in order to expand the scope of its analyses. We first discuss the features that enhance REDCATs user-friendly nature, such as the integration of a number of analyses into one single operation and enabling convenient examination of a structural ensemble in order to identify the most suitable structure. We then describe the new features which expand the scope of RDC analyses, performing exercises that utilize both synthetic and experimental data to illustrate and evaluate different features with regard to structure refinement and structure validation. RESULTS: We establish the seamless interaction that takes place between REDCAT, VMD, and Xplor-NIH in demonstrations that utilize our newly developed REDCAT-VMD and XplorGUI interfaces. These modules enable visualization of RDC analysis results on the molecular structure displayed in VMD and refinement of structures with Xplor-NIH, respectively. We also highlight REDCAT's Error-Analysis feature in reporting the localized fitness of a structure to RDC data, which provides a more effective means of recognizing local structural anomalies. This allows for structurally sound regions of a molecule to be identified, and for any refinement efforts to be focused solely on locally distorted regions. CONCLUSIONS: The newly engineered REDCAT software package, which is available for download via the WWW from http://ifestos.cse.sc.edu, has been developed in the Object Oriented C++ environment. Our most recent enhancements to REDCAT serve to provide a more complete RDC analysis suite, while also accommodating a more user-friendly experience, and will be of great interest to the community of researchers and developers since it hides the complications of software development.


Subject(s)
Molecular Structure , Nuclear Magnetic Resonance, Biomolecular , Proteins/chemistry , Software , Models, Molecular , United States , User-Computer Interface
13.
PLoS One ; 8(6): e64388, 2013.
Article in English | MEDLINE | ID: mdl-23750209

ABSTRACT

Mammosphere and breast tumoursphere culture have gained popularity as in vitro assays for propagating and analysing normal and cancer stem cells. Whether the spheres derived from different sources or parent cultures themselves are indeed single entities enriched in stem/progenitor cells compared to other culture formats has not been fully determined. We surveyed sphere-forming capacity across 26 breast cell lines, immunophenotyped spheres from six luminal- and basal-like lines by immunohistochemistry and flow cytometry and compared clonogenicity between sphere, adherent and matrigel culture formats using in vitro functional assays. Analyses revealed morphological and molecular intra- and inter-sphere heterogeneity, consistent with adherent parental cell line phenotypes. Flow cytometry showed sphere culture does not universally enrich for markers previously associated with stem cell phenotypes, although we found some cell-line specific changes between sphere and adherent formats. Sphere-forming efficiency was significantly lower than adherent or matrigel clonogenicity and constant over serial passage. Surprisingly, self-renewal capacity of sphere-derived cells was similar/lower than other culture formats. We observed significant correlation between long-term-proliferating-cell symmetric division rates in sphere and adherent cultures, suggesting functional overlap between the compartments sustaining them. Experiments with normal primary human mammary epithelia, including sorted luminal (MUC1(+)) and basal/myoepithelial (CD10(+)) cells revealed distinct luminal-like, basal-like and mesenchymal entities amongst primary mammospheres. Morphological and colony-forming-cell assay data suggested mammosphere culture may enrich for a luminal progenitor phenotype, or induce reversion/relaxation of the basal/mesenchymal in vitro selection occurring with adherent culture. Overall, cell line tumourspheres and primary mammospheres are not homogenous entities enriched for stem cells, suggesting a more cautious approach to interpreting data from these assays and careful consideration of its limitations. Sphere culture may represent an alternative 3-dimensional culture system which rather than universally 'enriching' for stem cells, has utility as one of a suite of functional assays that provide a read-out of progenitor activity.


Subject(s)
Breast Neoplasms/pathology , Mammary Glands, Human/pathology , Spheroids, Cellular/pathology , Cell Adhesion , Cell Line, Tumor , Flow Cytometry , Humans , Phenotype
14.
Zootaxa ; 3647: 201-50, 2013.
Article in English | MEDLINE | ID: mdl-26295106

ABSTRACT

Recent molecular phylogenetic studies of ants (Hymenoptera: Formicidae) have revolutionized our understanding of how these ecologically dominant organisms diversified, but detailed phylogenies are lacking for most major ant subfamilies. I report the results of the first detailed phylogenetic study of the ant subfamily Ponerinae, a diverse cosmopolitan lineage whose properties make it an attractive model system for investigating social and ecological evolution in ants. Molecular sequence data were obtained from four nuclear genes (wingless, long-wavelength rhodopsin, rudimentary [CAD], 28S rDNA; total of ~3.3 kb) for 86 ponerine taxa, representing all three ponerine tribes, 22 of the 28 currently recognized genera, and 14 of the 18 informal subgenera of Pachycondyla, a heterogeneous grouping whose monophyly is doubtful on morphological grounds. Phylogenetic reconstructions using maximum likelihood and Bayesian inference support the monophyly of Ponerinae and tribe Platythyreini, but fail to support the monophyly of the large tribe Ponerini due to its inclusion of the unusual genus Thaumatomyrmex. Pachycondyla is inferred to be broadly non-monophyletic. Numerous novel generic and suprageneric relationships are inferred within Ponerini, which was found to consist of four major multi-generic clades (the Ponera, Pachycondyla, Plectroctena and Odontomachus genus groups) plus the single genera Hypoponera and Harpegnathos. Uncertainty remains in some regions of the phylogeny, including at the base of Ponerini, possibly reflecting rapid radiation. Divergence dating using a Bayesian relaxed clock method estimates an origin for stem Ponerinae in the upper Cretaceous, a major burst of diversification near the K/T boundary, and a rich and continual history of diversification during the Cenozoic. These results fail to support the predictions of the "dynastic-succession hypothesis" previously developed to explain the high species diversity of Ponerinae. Though model-based reconstructions of historical biogeography and trait evolution were not attempted in this study, the phylogeny suggests that ponerine evolution was marked by regionalized radiations and frequent faunal exchange between major biogeographic provinces. The reported results also imply multiple origins of cryptobiotic foraging, mass raiding behavior, and gamergate reproduction within Ponerinae, highlighting the value of the subfamily as a model for studying the incipient evolution of these and other ecological and behavioral traits.


Subject(s)
Ants/classification , Ants/genetics , Animals , Ants/anatomy & histology , Ants/physiology , Databases, Genetic , Ecosystem , Phylogeny , Phylogeography , Social Behavior , Species Specificity , Time Factors
15.
PLoS One ; 7(12): e52692, 2012.
Article in English | MEDLINE | ID: mdl-23285151

ABSTRACT

Breast cancer is a heterogeneous disease, composed of tumour cells with differing gene expressions and phenotypes. Very few antigens have been identified and a better understanding of tumour initiating-cells as targets for therapy is critically needed. Recently, a rare subpopulation of cells within tumours has been described with the ability to: (i) initiate and sustain tumour growth; (ii) resist traditional therapies and allow for secondary tumour dissemination; and (iii) display some of the characteristics of stem cells such as self-renewal. These cells are termed tumour-initiating cells or cancer stem cells, or alternatively, in the case of breast cancer, breast cancer stem cells. Previous studies have demonstrated that breast cancer stem cells can be enriched for in "tumoursphere" culture. Proteomics represents a novel way to investigate protein expression between cells. We hypothesise that characterisation of the proteome of the breast cancer line MCF-7 tumourspheres compared to adherent/differentiated cells identifies proteins of novel interest for further isolating or targeting breast cancer stem cells. We present evidence that: (i) the proteome of adherent cells is different to the proteome of cells grown in sphere medium from either early passage (passage 2) or late passage (passage 5) spheres; (ii) that spheres are enriched in expression of a variety of tumour-relevant proteins (including MUC1 and Galectin-3); and (iii) that targeting of one of these identified proteins (galectin-3) using an inhibitor (N-acetyllactosamine) decreases sphere formation/self-renewal of MCF-7 cancer stem cells in vitro and tumourigenicity in vivo. Hence, proteomic analysis of tumourspheres may find use in identifying novel targets for future therapy. The therapeutic targeting of breast cancer stem cells, a highly clinically relevant sub-population of tumour cells, has the potential to eliminate residual disease and may become an important component of a multi-modality treatment of cancer.


Subject(s)
Breast Neoplasms/metabolism , Proteome , Proteomics , Breast Neoplasms/genetics , Cell Transformation, Neoplastic/genetics , Cell Transformation, Neoplastic/metabolism , Female , Galectin 1/genetics , Galectin 1/metabolism , Galectin 3/genetics , Galectin 3/metabolism , Humans , MCF-7 Cells , Mucin-1/genetics , Mucin-1/metabolism , Neoplastic Stem Cells/metabolism , Phenotype , Spheroids, Cellular , Tumor Cells, Cultured
16.
Clin Infect Dis ; 50(6): e34-7, 2010 Mar 15.
Article in English | MEDLINE | ID: mdl-20156061

ABSTRACT

We describe a unique case of fulminant infectious mononucleosis and recurrent Epstein-Barr virus reactivation presenting in an adolescent. Detailed assays of Epstein-Barr virus-specific T cell immunity revealed defects in the patient's T cell receptor signalling pathway characterized by a lack of interleukin-2 and CD25 expression, which may have contributed to her clinical course. Allogeneic stem cell transplantation reversed the clinical and laboratory phenotype.


Subject(s)
Herpesvirus 4, Human/immunology , Herpesvirus 4, Human/isolation & purification , Infectious Mononucleosis/diagnosis , Infectious Mononucleosis/immunology , Virus Activation , Adolescent , Child , Humans , Infectious Mononucleosis/therapy , Interleukin-2/deficiency , Interleukin-2 Receptor alpha Subunit/deficiency , Receptors, Antigen, T-Cell/deficiency , Recurrence , Stem Cell Transplantation , T-Lymphocytes/immunology , Young Adult
17.
Hum Reprod ; 25(2): 334-44, 2010 Feb.
Article in English | MEDLINE | ID: mdl-19920067

ABSTRACT

BACKGROUND: Early embryo development (EED) forms the basis of assisted reproductive technologies (ARTs), which are used to treat human infertility and to propagate other mammalian species. Thyroid hormones (THs) play an important role in the post-implantation development of the embryo in mammals; however, the effects of THs on pre-attachment embryos are not known. Currently utilized in-vitro embryo production media are devoid of THs and hence our main objective was to examine whether THs affected EED in a bovine model. METHODS: To determine if THs are present at the site of fertilization and EED in cattle, we evaluated the presence of the hormones in oviductal and uterine horn tissues. To assess the outcome of free TH supplementation (50 ng/ml of each hormone: triiodothyronine-T3 and thyroxin-T4), embryos were followed through standard and TH-supplemented in-vitro procedures, and evaluated for the cleavage rates, blastocyst formation rate and hatching rates. Embryo quality was assessed using TUNEL assay and post-cryopreservation survival was also evaluated. RESULTS: Although TH levels in in-vitro culture media were found to be approximately 60% of the administered doses, the TH-treated embryos exhibited significant increases in blastocyst formation and hatching rates (P < 0.05). Embryo quality was significantly improved in the treated groups as demonstrated by greater total cell counts and reduced proportions of apoptotic cells (P < 0.05). Finally, TH supplementation was associated with improved post-cryopreservation viability, defined by blastocyst re-expansion and hatching rates after frozen embryos had been thawed and cultured (P < 0.05). CONCLUSIONS: These findings not only provide a way of optimizing ART efficiency, but also further our understanding of how THs influence embryonic development in mammals.


Subject(s)
Embryo, Mammalian/drug effects , Embryonic Development/drug effects , Reproductive Techniques, Assisted/veterinary , Thyroid Hormones/pharmacology , Animals , Biological Availability , Cattle , Cryopreservation/veterinary , Embryo Culture Techniques , Female , Pregnancy , Thyroxine/pharmacology , Triiodothyronine/pharmacology
18.
Curr Opin Drug Discov Devel ; 12(4): 458-67, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19562642

ABSTRACT

PDE10A is a dual substrate PDE that is highly expressed in medium spiny neurons of the striatal complex. The inhibition of PDE10A produces effects that modulate basal ganglia function in ways that suggest a particular therapeutic utility in the treatment of psychosis in schizophrenia. Significant understanding of PDE10A at the molecular level has helped to guide efforts in inhibitor design, and many different inhibitor classes have now been discovered. At least one PDE10A inhibitor has been advanced into clinical trials to begin to test the hypothesis that such agents may be useful in the treatment of psychosis.


Subject(s)
Antipsychotic Agents/pharmacology , Drug Discovery , Phosphodiesterase Inhibitors/pharmacology , Phosphoric Diester Hydrolases/metabolism , Animals , Antipsychotic Agents/chemistry , Antipsychotic Agents/therapeutic use , Basal Ganglia/drug effects , Basal Ganglia/enzymology , Humans , Ligands , Models, Molecular , Molecular Structure , Neurons/drug effects , Neurons/enzymology , Phosphodiesterase Inhibitors/chemistry , Phosphodiesterase Inhibitors/therapeutic use , Protein Binding , Schizophrenia/drug therapy
19.
Vaccine ; 27(23): 3053-62, 2009 May 18.
Article in English | MEDLINE | ID: mdl-19428919

ABSTRACT

Ingenol-3-angelate is a new local chemotherapeutic agent in clinical trails that induces primary necrosis of tumour cells and transient local inflammation. Here we show that cure of subcutaneous tumours with ingenol-3-angelate (PEP005) resulted in the generation of anti-cancer CD8 T cells that could regress metastases. Furthermore, PEP005-mediated cure synergized with several CD8 T cell-based immunotherapies to regress further distant metastases. PEP005 was shown to have adjuvant properties, being able to upregulate CD80 and CD86 expression on dendritic cells in vivo, and to promote CD8 T cell induction when co-delivered with a protein antigen. PEP005 thus emerges as a unique local chemotherapeutic immunostimulatory debulking agent that could be used in conjunction with immunotherapies to promote regression of metastases.


Subject(s)
Cancer Vaccines/therapeutic use , Diterpenes/therapeutic use , Immunization/methods , Neoplasms/drug therapy , Adjuvants, Immunologic/therapeutic use , Animals , Cancer Vaccines/immunology , Carcinoma, Lewis Lung/drug therapy , Carcinoma, Lewis Lung/immunology , Cell Culture Techniques , Chickens , Colonic Neoplasms/drug therapy , Colonic Neoplasms/immunology , Dendritic Cells/immunology , Female , Humans , Lung Neoplasms/drug therapy , Lung Neoplasms/immunology , Lung Neoplasms/secondary , Melanoma, Experimental/drug therapy , Melanoma, Experimental/immunology , Mice , Neoplasm Transplantation , Neoplasms/immunology , T-Lymphocytes/immunology
20.
Breast Cancer Res ; 10(4): 210, 2008.
Article in English | MEDLINE | ID: mdl-18671830

ABSTRACT

The concept of cancer stem cells responsible for tumour origin, maintenance, and resistance to treatment has gained prominence in the field of breast cancer research. The therapeutic targeting of these cells has the potential to eliminate residual disease and may become an important component of a multimodality treatment. Recent improvements in immunotherapy targeting of tumour-associated antigens have advanced the prospect of targeting breast cancer stem cells, an approach that might lead to more meaningful clinical remissions. Here, we review the role of stem cells in the healthy breast, the role of breast cancer stem cells in disease, and the potential to target these cells.


Subject(s)
Breast Neoplasms/diagnosis , Breast Neoplasms/pathology , Neoplastic Stem Cells/cytology , Antigens, Neoplasm/metabolism , Breast/pathology , Cell Differentiation , Dendritic Cells/cytology , Female , Humans , Immunotherapy/methods , Neoplasm Metastasis , Neoplastic Stem Cells/pathology , Signal Transduction , Stem Cells/cytology , Time Factors , Treatment Outcome
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