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1.
Cell ; 167(1): 187-202.e17, 2016 Sep 22.
Article in English | MEDLINE | ID: mdl-27662089

ABSTRACT

Inflammasome complexes function as key innate immune effectors that trigger inflammation in response to pathogen- and danger-associated signals. Here, we report that germline mutations in the inflammasome sensor NLRP1 cause two overlapping skin disorders: multiple self-healing palmoplantar carcinoma (MSPC) and familial keratosis lichenoides chronica (FKLC). We find that NLRP1 is the most prominent inflammasome sensor in human skin, and all pathogenic NLRP1 mutations are gain-of-function alleles that predispose to inflammasome activation. Mechanistically, NLRP1 mutations lead to increased self-oligomerization by disrupting the PYD and LRR domains, which are essential in maintaining NLRP1 as an inactive monomer. Primary keratinocytes from patients experience spontaneous inflammasome activation and paracrine IL-1 signaling, which is sufficient to cause skin inflammation and epidermal hyperplasia. Our findings establish a group of non-fever inflammasome disorders, uncover an unexpected auto-inhibitory function for the pyrin domain, and provide the first genetic evidence linking NLRP1 to skin inflammatory syndromes and skin cancer predisposition.


Subject(s)
Adaptor Proteins, Signal Transducing/genetics , Apoptosis Regulatory Proteins/genetics , Carcinoma/genetics , Genetic Predisposition to Disease , Inflammasomes/metabolism , Keratosis/genetics , Skin Neoplasms/genetics , Adaptor Proteins, Signal Transducing/chemistry , Amino Acid Sequence , Apoptosis Regulatory Proteins/chemistry , Carcinoma/pathology , Chromosomes, Human, Pair 17/genetics , Epidermis/pathology , Germ-Line Mutation , Humans , Hyperplasia/genetics , Hyperplasia/pathology , Inflammasomes/genetics , Interleukin-1/metabolism , Keratosis/pathology , NLR Proteins , Paracrine Communication , Pedigree , Protein Domains , Pyrin/chemistry , Signal Transduction , Skin Neoplasms/pathology , Syndrome
2.
BMC Med ; 22(1): 41, 2024 01 29.
Article in English | MEDLINE | ID: mdl-38281908

ABSTRACT

BACKGROUND: Conventional vector control strategies have significantly reduced the malaria burden. The sustainability of these methods is currently challenged. Odour-based traps are emerging technologies that can complement the existing tools. Implementation of odour-based traps for mass trapping is limited due to the restricted range of vectors caught with available carbon dioxide-dependent lures, and the lack of comprehensive field studies. The objective of this study was to assess the impact of odour-mediated mass trapping targeting outdoor vectors, using a synthetic cattle urine lure that attracts a wide range of vector species in a variety of physiological states, on malaria prevalence and entomological parameters to determine malaria transmission intensities. METHODS: A controlled before-and-after study was conducted in two rural communities in southern Ethiopia. Baseline monthly entomological and seasonal cross-sectional malaria prevalence surveys were conducted in both communities for a year. Then, mass trapping of mosquitoes was conducted in one of the villages, while the monthly entomological surveillance and seasonal malaria prevalence surveys continued in both villages. Generalised linear mixed models were constructed and tested to determine which factors were significantly affected by the intervention. RESULTS: Mass trapping contributed to the reduction of the population of the principal malaria vector, Anopheles arabiensis, and the associated entomological indicators, the human bite rate (HBR) and the entomological inoculation rate (EIR), in the intervention village compared to the control village. The intervention village had an average HBR by An. arabiensis of 3.0 (95% CI 1.4-4.6) during the peak malaria transmission season, compared to 10.5 (95% CI - 0.5-21.5; P < 0.0001) in the control village. The intervention village (mean 0.02, 95% CI - 0.05-0.4.8) had a daily EIR eight times lower than the control village (mean 0.17, 95% CI), which likely contributed to the reduced malaria prevalence in the intervention community following its introduction by ca. 60% (95% CI 55-63). CONCLUSIONS: The combined use of odour-based mass trapping and conventional control strategies coincided with a reduction of human-vector contact and malaria prevalence, providing support for odour-baited technologies as a viable option for next-generation vector control tools. Further cluster-randomised control studies are recommended in different eco-epidemiological settings with varying malaria transmission intensities.


Subject(s)
Anopheles , Malaria , Humans , Animals , Cattle , Malaria/epidemiology , Malaria/prevention & control , Anopheles/physiology , Odorants , Cross-Sectional Studies , Mosquito Vectors , Mosquito Control/methods
3.
Med Vet Entomol ; 37(4): 683-692, 2023 12.
Article in English | MEDLINE | ID: mdl-37265439

ABSTRACT

Vector control is still the recommended approach to avoid arbovirus outbreaks. Herein, we investigate oviposition preferences of Aedes aegypti (Diptera: Culicidae) females under a semi-field structure Rio de Janeiro, Brazil. For that, in Experiment 1, we used two settings: 'Single items', which included as containers drain, beer bottle, bucket, car tyre, water tank, and a potted Peace Lily (Spathiphyllum wallisii) in a saucer with water, or 'Multiple containers', as an urban simulation, in which one drain, two additional beer bottles, and an extra plant pot saucer were added. Experiment 2 (sensory cues) used five variations of potted plant, each one varying in the range of sensory cues known to attract gravid females to oviposition containers. Our results indicate that gravid Ae. aegypti prefer to oviposit close to the ground and in open water containers with organic compounds from plant watering. Domestic large artificial containers containing tap water received significantly fewer eggs, except for the car tyre, which exhibited as many eggs as the potted plant. We also show that visual (potted plant shape) and olfactory clues (odour of the plant or from water containing organic matter) were equally attractive separately as were these stimuli together.


Subject(s)
Aedes , Female , Animals , Oviposition , Mosquito Vectors , Brazil , Water
4.
Mol Ther ; 29(2): 734-743, 2021 02 03.
Article in English | MEDLINE | ID: mdl-33038324

ABSTRACT

Advanced, late-stage Epstein-Barr virus (EBV)-positive nasopharyngeal carcinoma (NPC) is incurable, and its treatment remains a clinical and therapeutic challenge. Results from a phase II clinical trial in advanced NPC patients employing a combined chemotherapy and EBV-specific T cell (EBVST) immunotherapy regimen showed a response rate of 71.4%. Longitudinal analysis of patient samples showed that an increase in EBV DNA plasma concentrations and the peripheral monocyte-to-lymphocyte ratio negatively correlated with overall survival. These parameters were combined into a multivariate analysis to stratify patients according to risk of death. Immunophenotyping at serial time points showed that low-risk individuals displayed significantly decreased amounts of monocytic myeloid-derived suppressor cells postchemotherapy, which subsequently influenced successful cytotoxic T-lymphocyte (CTL) immunotherapy. Examination of the low-risk group, 2 weeks post-EBVST infusion, showed that individuals with a greater overall survival possessed an increased frequency of CD8 central and effector memory T cells, together with higher levels of plasma interferon (IFN)-γ, and cytotoxic lymphocyte-associated transcripts. These results highlight the importance of the rational selection of chemotherapeutic agents and consideration of their impact on both systemic immune responses and downstream cellular immunotherapy outcomes.


Subject(s)
Immunotherapy, Adoptive , Myeloid-Derived Suppressor Cells/immunology , Nasopharyngeal Carcinoma/immunology , Nasopharyngeal Carcinoma/therapy , T-Lymphocytes/immunology , Epstein-Barr Virus Infections/immunology , Herpesvirus 4, Human/immunology , Humans , Immunotherapy, Adoptive/methods , Myeloid-Derived Suppressor Cells/metabolism , Nasopharyngeal Carcinoma/pathology , T-Lymphocytes/metabolism , T-Lymphocytes, Cytotoxic/immunology , T-Lymphocytes, Cytotoxic/metabolism , Treatment Failure , Treatment Outcome
6.
J Med Internet Res ; 22(8): e17019, 2020 08 13.
Article in English | MEDLINE | ID: mdl-32788150

ABSTRACT

BACKGROUND: Improving recovery from acute symptoms and preventing relapse are two significant challenges in severe mental illness. We developed a personalized smartphone-based app to monitor symptoms in real time and validated its acceptance, reliability, and validity. OBJECTIVE: To assess (i) acceptability of continuous monitoring to SMI patients and health professionals over 3 months; (ii) impact of active self-monitoring on positive psychotic symptoms assessed at 6 and 12 weeks; and (iii) the feasibility of detecting early warning signs of relapse. METHODS: The active symptom monitoring smartphone app was built into an end-to-end system in two NHS Trusts to enable real-time symptom self-monitoring and detection by the clinical team of early signs of relapse in people with severe mental illness. We conducted an open randomized controlled trial of active symptom monitoring compared to usual management to assess: (i) acceptability and safety of continuous monitoring over 3 months; (ii) impact of active self-monitoring on positive psychotic symptoms assessed at 6 and 12 weeks; (iii) feasibility of detecting early warning signs of relapse communicated to the healthcare staff via an app streaming data to the electronic health record. Eligible participants with a Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (DSM-IV) diagnosis of schizophrenia and related disorders, and a history of relapse within the previous two years were enrolled from an early intervention team and a community mental health team. RESULTS: Of 181 eligible patients, 81 (45%) consented and were randomized to either active symptom monitoring or management as usual. At 12 weeks, 90% (33/36) of those in the active monitoring group continued to use the system and exhibited an adherence rate (defined as responding to >33% of alerts) of 84% (30/36}. Active symptom monitoring was associated with no difference on the empowerment scale in comparison to the usual management group at 12 weeks. The pre-planned intent-to-treat analysis of the primary outcome, a positive score on the Positive and Negative Syndrome Scale (PANSS) scale, showed a significant reduction in the active symptom monitoring group over 12 weeks in the early intervention center. Alerts for personalized early warning signs of relapse were built into the workflows of both NHS Trusts, and 100% of health professional staff used the system in a new digital workflow. Qualitative analyses supported the acceptability of the system to participants and staff. CONCLUSIONS: The active smartphone monitoring system is feasible and was accepted by users in a 3-month study of people with severe mental illness, with surprisingly high levels of adherence. App use was associated with psychotic symptom improvement in recent-onset participants, but not those with longstanding illness, supporting the notion of improved self-management. When built into clinical management workflows to enable personalized alerts of symptom deterioration, the app has demonstrated utility in promoting earlier intervention for relapse. TRIAL REGISTRATION: ISRCTN Registry ISRCTN88145142; http://www.isrctn.com/ISRCTN88145142.


Subject(s)
Mobile Applications/standards , Smartphone/standards , Telemedicine/methods , Adult , Female , Humans , Male , Middle Aged , Reproducibility of Results , Self-Management , Young Adult
7.
J Biol Chem ; 293(49): 18864-18878, 2018 12 07.
Article in English | MEDLINE | ID: mdl-30291141

ABSTRACT

The inflammasome is a critical molecular complex that activates interleukin-1 driven inflammation in response to pathogen- and danger-associated signals. Germline mutations in the inflammasome sensor NLRP1 cause Mendelian systemic autoimmunity and skin cancer susceptibility, but its endogenous regulation remains less understood. Here we use a proteomics screen to uncover dipeptidyl dipeptidase DPP9 as a novel interacting partner with human NLRP1 and a related inflammasome regulator, CARD8. DPP9 functions as an endogenous inhibitor of NLRP1 inflammasome in diverse primary cell types from human and mice. DPP8/9 inhibition via small molecule drugs and CRISPR/Cas9-mediated genetic deletion specifically activate the human NLRP1 inflammasome, leading to ASC speck formation, pyroptotic cell death, and secretion of cleaved interleukin-1ß. Mechanistically, DPP9 interacts with a unique autoproteolytic domain (Function to Find Domain (FIIND)) found in NLRP1 and CARD8. This scaffolding function of DPP9 and its catalytic activity act synergistically to maintain NLRP1 in its inactive state and repress downstream inflammasome activation. We further identified a single patient-derived germline missense mutation in the NLRP1 FIIND domain that abrogates DPP9 binding, leading to inflammasome hyperactivation seen in the Mendelian autoinflammatory disease Autoinflammation with Arthritis and Dyskeratosis. These results unite recent findings on the regulation of murine Nlrp1b by Dpp8/9 and uncover a new regulatory mechanism for the NLRP1 inflammasome in primary human cells. Our results further suggest that DPP9 could be a multifunctional inflammasome regulator involved in human autoinflammatory diseases.


Subject(s)
Adaptor Proteins, Signal Transducing/metabolism , Apoptosis Regulatory Proteins/metabolism , Dipeptidyl-Peptidases and Tripeptidyl-Peptidases/metabolism , Inflammasomes/metabolism , Adaptor Proteins, Signal Transducing/antagonists & inhibitors , Adaptor Proteins, Signal Transducing/genetics , Apoptosis Regulatory Proteins/antagonists & inhibitors , Apoptosis Regulatory Proteins/genetics , Boronic Acids/pharmacology , CARD Signaling Adaptor Proteins/metabolism , Dipeptides/pharmacology , Dipeptidyl-Peptidases and Tripeptidyl-Peptidases/antagonists & inhibitors , Enzyme Inhibitors/pharmacology , Germ-Line Mutation , HEK293 Cells , Humans , Inflammation/genetics , Mutation, Missense , NLR Proteins , Neoplasm Proteins/metabolism , Protein Binding , Protein Domains
8.
PLoS Pathog ; 12(8): e1005773, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27490374

ABSTRACT

The ecological context in which mosquitoes and malaria parasites interact has received little attention, compared to the genetic and molecular aspects of malaria transmission. Plant nectar and fruits are important for the nutritional ecology of malaria vectors, but how the natural diversity of plant-derived sugar sources affects mosquito competence for malaria parasites is unclear. To test this, we infected Anopheles coluzzi, an important African malaria vector, with sympatric field isolates of Plasmodium falciparum, using direct membrane feeding assays. Through a series of experiments, we then examined the effects of sugar meals from Thevetia neriifolia and Barleria lupilina cuttings that included flowers, and fruit from Lannea microcarpa and Mangifera indica on parasite and mosquito traits that are key for determining the intensity of malaria transmission. We found that the source of plant sugar meal differentially affected infection prevalence and intensity, the development duration of the parasites, as well as the survival and fecundity of the vector. These effects are likely the result of complex interactions between toxic secondary metabolites and the nutritional quality of the plant sugar source, as well as of host resource availability and parasite growth. Using an epidemiological model, we show that plant sugar source can be a significant driver of malaria transmission dynamics, with some plant species exhibiting either transmission-reducing or -enhancing activities.


Subject(s)
Culicidae , Feeding Behavior , Insect Vectors , Malaria, Falciparum/transmission , Plants , Animals , Humans
9.
Malar J ; 17(1): 351, 2018 Oct 05.
Article in English | MEDLINE | ID: mdl-30290799

ABSTRACT

BACKGROUND: Understanding the ecology of exophilic anophelines is a key step toward developing outdoor control strategies to complement existing indoor control tools against malaria vectors. This study was conducted to assess the movement pattern of exophilic Anopheles mosquitoes between blood meal sources and resting habitats, and the landscape factors dictating their resting habitat choice. RESULTS: Resting clay pots were placed at 5 m, 25 m, 50 m, 75 m and 100 m away from isolated focal houses, radiating from them in four directions. The locations of the clay pots represent heterogeneous land cover types at a relatively fine spatial scale in the landscape. The effect of the landscape characters on the number of both female and male anophelines caught was modelled using zero-inflated negative binomial regression with a log link function. A total of 420 Anopheles mosquitoes (353 females and 67 males) belonging to three species; Anopheles arabiensis, Anopheles pharoensis, and Anopheles tenebrosus were caught in the resting clay pots, with An. arabiensis being the dominant species. Canopy cover, distance from the house, and land cover type were the significant landscape characters influencing the aggregation of resting mosquitoes. Both the count and binary models showed that canopy cover was the strongest predictor variable on the counts and the presence of Anopheles mosquitoes in the clay pots. Female Anopheles were most frequently found resting in the pots placed in banana plantations, and at sampling points that were at the greater distances (75 m and 100 m) from the focal house. CONCLUSIONS: This study showed that exophilic Anopheles mosquitoes tend to rest in shaded areas some distance away from human habitation. These findings are important when targeting mosquitoes outdoors, complementing the existing effort being made to control malaria vectors indoors.


Subject(s)
Animal Distribution , Anopheles/physiology , Mosquito Vectors/physiology , Animals , Ethiopia , Female , Male , Mosquito Control , Movement , Species Specificity
10.
Proc Natl Acad Sci U S A ; 112(45): E6195-204, 2015 Nov 10.
Article in English | MEDLINE | ID: mdl-26512111

ABSTRACT

Glomerulonephritis is a common and debilitating feature of systemic lupus erythematosus (SLE). The precise immune mechanisms that drive the progression from benign autoimmunity to glomerulonephritis are largely unknown. Previous investigations have shown that a moderate increase of the innate Toll-like receptor 7 (TLR7) is sufficient for the development of nephritis. In these systems normalization of B-cell TLR7 expression or temporal depletion of plasmacytoid dendritic cells (pDCs) slow progression; however, the critical cell that is responsible for driving full immunopathology remains unidentified. In this investigation we have shown that conventional DC expression of TLR7 is essential for severe autoimmunity in the Sle1Tg7 model of SLE. We show that a novel expanding CD11b(+) conventional DC subpopulation dominates the infiltrating renal inflammatory milieu, localizing to the glomeruli. Moreover, exposure of human myeloid DCs to IFN-α or Flu increases TLR7 expression, suggesting they may have a role in self-RNA recognition pathways in clinical disease. To our knowledge, this study is the first to highlight the importance of conventional DC-TLR7 expression for kidney pathogenesis in a murine model of SLE.


Subject(s)
Dendritic Cells/metabolism , Lupus Nephritis/physiopathology , Toll-Like Receptor 7/metabolism , Up-Regulation , Analysis of Variance , Animals , Base Sequence , CD11b Antigen/metabolism , DNA Primers/genetics , Flow Cytometry , Gene Expression Profiling/methods , Humans , Image Processing, Computer-Assisted , Kidney Glomerulus/cytology , Kidney Glomerulus/pathology , Lupus Nephritis/metabolism , Mice , Microscopy, Confocal , Molecular Sequence Data , Real-Time Polymerase Chain Reaction , Sequence Analysis, RNA , Statistics, Nonparametric
11.
Malar J ; 16(1): 262, 2017 07 01.
Article in English | MEDLINE | ID: mdl-28668084

ABSTRACT

BACKGROUND: Utilization of long-lasting insecticidal nets (LLINs) is regarded as key malaria prevention and control strategy. However, studies have reported a large gap in terms of both ownership and utilization particularly in the sub-Saharan Africa (SSA). With continual efforts to improve the use of LLIN and to progress malaria elimination, examining the factors influencing the ownership and usage of LLIN is of high importance. Therefore, the current study was conducted to examine the level of ownership and use of LLIN along with identification of associated factors at household level. METHODS: A cross-sectional study was conducted in Mirab Abaya District, Southern Ethiopia in June and July 2014. A total of 540 households, with an estimated 2690 members, were selected in four kebeles of the district known to have high incidence of malaria. Trained data collectors interviewed household heads to collect information on the knowledge, ownership and utilization of LLINs, which was complemented by direct observation on the conditions and use of the nets through house-to-house visit. Bivariate and multivariable logistic regression analyses were used to determine factors associated to LLIN use. RESULTS: Of 540 households intended to be included in the survey, 507 responded to the study (94.24% response rate), covering the homes of 2759 people. More than 58% of the households had family size >5 (the regional average), and 60.2% of them had at least one child below the age of 5 years. The ownership of at least one LLIN among households surveyed was 89.9%, and using at least one LLIN during the night prior to the survey among net owners was 85.1% (n = 456). Only 36.7% (186) mentioned at least as the mean of correct scores of all participants for 14 possible malaria symptoms and 32.7% (166) knew at least as the mean of correct scores of all participants for possible preventive methods. Over 30% of nets owned by the households were out of use. After controlling for confounding factors, having two or more sleeping places (adjusted odds ratio [aOR] = 2.58, 95% CI 1.17, 5.73), knowledge that LLIN prevents malaria (aOR = 2.51, 95% CI 1.17, 5.37), the presence of hanging bed nets (aOR = 19.24, 95% CI 9.24, 40.07) and walls of the house plastered or painted >12 months ago (aOR = 0.09, 95% CI 0.01, 0.71) were important predictors of LLIN utilization. CONCLUSIONS: This study found a higher proportion of LLIN ownership and utilization by households than had previously been found in similar studies in Ethiopia, and in many studies in SSA. However, poor knowledge of the transmission mechanisms and the symptoms of malaria, and vector control measures to prevent malaria were evident. Moderate proportions of nets were found to be out of use or in poor repair. Efforts should be in place to maintain the current rate of utilization of LLIN in the district and improve on the identified gaps in order to support the elimination of malaria.


Subject(s)
Insecticide-Treated Bednets/statistics & numerical data , Malaria/prevention & control , Malaria/psychology , Mosquito Control/methods , Ownership/statistics & numerical data , Adolescent , Adult , Aged , Cross-Sectional Studies , Ethiopia , Family Characteristics , Female , Humans , Male , Middle Aged , Young Adult
12.
Malar J ; 16(1): 65, 2017 02 07.
Article in English | MEDLINE | ID: mdl-28173804

ABSTRACT

BACKGROUND: The reproductive success and population dynamics, of Anopheles malaria mosquitoes is strongly influenced by the oviposition site selection of gravid females. Mosquitoes select oviposition sites at different spatial scales, starting with selecting a habitat in which to search. This study utilizes the association of larval abundance in the field with natural breeding habitats, dominated by various types of wild grasses, as a proxy for oviposition site selection by gravid mosquitoes. Moreover, the role of olfactory cues emanating from these habitats in the attraction and oviposition stimulation of females was analysed. METHODS: The density of Anopheles larvae in breeding sites associated with Echinochloa pyramidalis, Echinochloa stagnina, Typha latifolia and Cyperus papyrus, was sampled and the larvae identified to species level. Headspace volatile extracts of the grasses were collected and used to assess behavioural attraction and oviposition stimulation of gravid Anopheles arabiensis and Anopheles coluzzii mosquitoes in wind tunnel and two-choice oviposition assays, respectively. The ability of the mosquitoes to differentiate among the grass volatile extracts was tested in multi-choice tent assays. RESULTS: Anopheles arabiensis larvae were the most abundant species found in the various grass-associated habitats. The larval densities described a hierarchical distribution, with Poaceae (Echinochloa pyramidalis and Echinochloa stagnina)-associated habitat sites demonstrating higher densities than that of Typha-associated sites, and where larvae were absent from Cyperus-associated sites. This hierarchy was maintained by gravid An. arabiensis and An. coluzzii mosquitoes in attraction, oviposition and multi-choice assays to grass volatile extracts. CONCLUSIONS: The demonstrated hierarchical preference of gravid An. coluzzii and An. arabiensis for grass volatiles indicates that vegetation cues associated with larval habitats are instrumental in the oviposition site choice of the malaria mosquitoes. Identifying volatile cues from grasses that modulate gravid malaria mosquito behaviours has distinct potential for the development of tools to be used in future monitoring and control methods.


Subject(s)
Anopheles/physiology , Chemotaxis , Oviposition , Volatile Organic Compounds/metabolism , Animals , Anopheles/growth & development , Cyperus/chemistry , Echinochloa/chemistry , Ecosystem , Female , Larva/growth & development , Larva/physiology , Population Density , Smell , Species Specificity , Typhaceae/chemistry
13.
J Insect Sci ; 17(5)2017 Sep 01.
Article in English | MEDLINE | ID: mdl-28922900

ABSTRACT

Nutrients in breeding sites are critical for the survival and development of malaria mosquitoes, having a direct impact on vectorial capacity. Yet, there is a limited understanding about the natural larval diet and its impact on the individual fitness of mosquitoes. Recent studies have shown that gravid Anopheles arabiensis Patton (Diptera: Culicidae) are attracted by and oviposit in grass-associated habitats. The pollen provided by these grasses is a potential source of nutrients for the larvae. Here, we assess the effect of Typha latifolia L. (Poales: Typhaceae), Echinochloa pyramidalis Lamarck, Pennisetum setaceum Forsskål, and Zea mays L. pollen on larval survival and rate of development in An. arabiensis under laboratory conditions. In addition, we characterize the carbon to nitrogen ratio and the size of pollen grains as a measure of diet quality. Carbon-rich pollen with a small grain size (T. latifolia and P. setaceum; 9.7 ± 0.3 × 103 and 5.5 ± 0.2 × 104 µm3, respectively) resulted in enhanced rates of development of An. arabiensis. In contrast, the larva fed on the nitrogen-rich control diet (TetraMin) was slower to develop, but demonstrated the highest larval survival. Larvae fed on carbon-rich and large-grained Z. mays pollen (4.1 ± 0.2 × 105 µm3) survived at similar levels as those fed on the control diet and also took a longer time to develop compared with larvae fed on the other pollens. While males and females did not appear to develop differently on the different pollen diets, males consistently emerged faster than their female counterparts. These results are discussed in relation to integrated vector management.


Subject(s)
Anopheles/physiology , Diet , Longevity , Nutritive Value , Poaceae , Pollen/chemistry , Typhaceae/chemistry , Animals , Anopheles/growth & development , Female , Larva/growth & development , Male
14.
Biochem Biophys Res Commun ; 478(2): 831-7, 2016 09 16.
Article in English | MEDLINE | ID: mdl-27501759

ABSTRACT

Wharton's jelly mesenchymal stem cells (WJMSCs) are being increasingly recognized for their ectodermal differentiation potential. Previously, we demonstrated that when WJMSC were seeded onto an acellular matrix material derived from Wharton's jelly and cultured in osteogenic induction media, generated CK19 positive cells and hair-like structures indicative of ectodermal differentiation of WJMSCs. In this manuscript, we examine the underlying mechanism behind this observation using a variety of microscopy and molecular biology techniques such as western blotting and qPCR. We demonstrate that these hair-like structures are associated with live cells that are positive for epithelial and mesenchymal markers such as cytokeratin-19 and α-smooth muscle actin, respectively. We also show that up-regulation of ß-catenin and noggin, along with the expression of TGF-ß and SMAD and inhibition of BMP4 could be the mechanism behind this ectodermal differentiation and hair-like structure formation.


Subject(s)
Gene Expression Regulation , Keratin-19/genetics , Mesenchymal Stem Cells/metabolism , Osteogenesis/genetics , Wharton Jelly/metabolism , Actins/genetics , Actins/metabolism , Biomarkers/metabolism , Bone Morphogenetic Protein 4/genetics , Bone Morphogenetic Protein 4/metabolism , Carrier Proteins/genetics , Carrier Proteins/metabolism , Cell Differentiation , Humans , Keratin-19/metabolism , Mesenchymal Stem Cells/cytology , Phenotype , Primary Cell Culture , Smad Proteins/genetics , Smad Proteins/metabolism , Transforming Growth Factor beta/genetics , Transforming Growth Factor beta/metabolism , Umbilical Cord/cytology , Umbilical Cord/metabolism , Wharton Jelly/cytology , beta Catenin/genetics , beta Catenin/metabolism
15.
Malar J ; 15(1): 253, 2016 May 04.
Article in English | MEDLINE | ID: mdl-27142303

ABSTRACT

BACKGROUND: Mosquito habitat-association studies are an important basis for disease control programmes and/or vector distribution models. However, studies do not explicitly account for incomplete detection during larval presence and abundance surveys, with potential for significant biases because of environmental influences on larval behaviour and sampling efficiency. METHODS: Data were used from a dip-sampling study for Anopheles larvae in Ethiopia to evaluate the effect of six factors previously associated with larval sampling (riparian vegetation, direct sunshine, algae, water depth, pH and temperature) on larval presence and detectability. Comparisons were made between: (i) a presence-absence logistic regression where samples were pooled at the site level and detectability ignored, (ii) a success versus trials binomial model, and (iii) a presence-detection mixture model that separately estimated presence and detection, and fitted different explanatory variables to these estimations. RESULTS: Riparian vegetation was consistently highlighted as important, strongly suggesting it explains larval presence (-). However, depending on how larval detectability was estimated, the other factors showed large variations in their statistical importance. The presence-detection mixture model provided strong evidence that larval detectability was influenced by sunshine and water temperature (+), with weaker evidence for algae (+) and water depth (-). For larval presence, there was also some evidence that water depth (-) and pH (+) influenced site occupation. The number of dip-samples needed to determine if larvae were likely present at a site was condition dependent: with sunshine and warm water requiring only two dips, while cooler water and cloud cover required 11. CONCLUSIONS: Environmental factors influence true larval presence and larval detectability differentially when sampling in field conditions. Researchers need to be more aware of the limitations and possible biases in different analytical approaches used to associate larval presence or abundance with local environmental conditions. These effects can be disentangled using data that are routinely collected (i.e., multiple dip samples at each site) by employing a modelling approach that separates presence from detectability.


Subject(s)
Anopheles/growth & development , Ecosystem , Larva/growth & development , Mosquito Vectors/physiology , Animals , Entomology/methods , Environment , Ethiopia
16.
Cell Mol Neurobiol ; 34(2): 173-81, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24213248

ABSTRACT

Cell-penetrating peptides (CPPs) are small peptides (typically 5-25 amino acids), which are used to facilitate the delivery of normally non-permeable cargos such as other peptides, proteins, nucleic acids, or drugs into cells. However, several recent studies have demonstrated that the TAT CPP has neuroprotective properties. Therefore, in this study, we assessed the TAT and three other CPPs (penetratin, Arg-9, Pep-1) for their neuroprotective properties in cortical neuronal cultures following exposure to glutamic acid, kainic acid, or in vitro ischemia (oxygen-glucose deprivation). Arg-9, penetratin, and TAT-D displayed consistent and high level neuroprotective activity in both the glutamic acid (IC50: 0.78, 3.4, 13.9 µM) and kainic acid (IC50: 0.81, 2.0, 6.2 µM) injury models, while Pep-1 was ineffective. The TAT-D isoform displayed similar efficacy to the TAT-L isoform in the glutamic acid model. Interestingly, Arg-9 was the only CPP that displayed efficacy when washed-out prior to glutamic acid exposure. Neuroprotection following in vitro ischemia was more variable with all peptides providing some level of neuroprotection (IC50; Arg-9: 6.0 µM, TAT-D: 7.1 µM, penetratin/Pep-1: >10 µM). The positive control peptides JNKI-1D-TAT (JNK inhibitory peptide) and/or PYC36L-TAT (AP-1 inhibitory peptide) were neuroprotective in all models. Finally, in a post-glutamic acid treatment experiment, Arg-9 was highly effective when added immediately after, and mildly effective when added 15 min post-insult, while the JNKI-1D-TAT control peptide was ineffective when added post-insult. These findings demonstrate that different CPPs have the ability to inhibit neurodamaging events/pathways associated with excitotoxic and ischemic injuries. More importantly, they highlight the need to interpret neuroprotection studies when using CPPs as delivery agents with caution. On a positive note, the cytoprotective properties of CPPs suggests they are ideal carrier molecules to deliver neuroprotective drugs to the CNS following injury and/or potential neuroprotectants in their own right.


Subject(s)
Cell-Penetrating Peptides/pharmacology , Cerebral Cortex/pathology , Glutamic Acid/toxicity , Ischemia/pathology , Kainic Acid/toxicity , Neurons/pathology , Neuroprotective Agents/pharmacology , Amino Acid Sequence , Animals , Carrier Proteins/chemistry , Carrier Proteins/pharmacology , Cell Survival/drug effects , Cell-Penetrating Peptides/chemistry , Cells, Cultured , Cysteamine/analogs & derivatives , Cysteamine/chemistry , Cysteamine/pharmacology , Gene Products, tat/chemistry , Gene Products, tat/pharmacology , Inhibitory Concentration 50 , Models, Biological , Molecular Sequence Data , Neurons/drug effects , Neurons/metabolism , Neurotoxins/toxicity , Oligopeptides/chemistry , Oligopeptides/pharmacology , Peptides/chemistry , Peptides/pharmacology , Rats , Rats, Sprague-Dawley
17.
J Immunol ; 189(12): 5786-96, 2012 Dec 15.
Article in English | MEDLINE | ID: mdl-23150717

ABSTRACT

Systemic lupus erythematosus (SLE) is a chronic systemic autoimmune disease characterized by the production of antinuclear autoantibodies. Antinuclear autoantibody development is recognized as one of the initial stages of disease that often results in systemic inflammation, kidney disease, and death. The etiology is complex, but it is clear that innate pathways may play an important role in disease progression. Recent data have highlighted an important role for the TLR family, particularly TLR7, in both human disease and murine models. In this study, we have presented a low copy conditional TLR7 transgenic (Tg7) mouse strain that does not develop spontaneous autoimmunity. When we combine Tg7 with the Sle1 lupus susceptibility locus, the mice develop severe disease. Using the CD19(Cre) recombinase system, we normalized expression of TLR7 solely within the B cells. Using this method we demonstrated that overexpression of TLR7 within the B cell compartment reduces the marginal zone B cell compartment and increases B and T cell activation but not T follicular helper cell development. Moreover, this enhanced B cell TLR7 expression permits the specific development of Abs to RNA/protein complexes and exacerbates SLE disease.


Subject(s)
Autoantibodies/biosynthesis , B-Lymphocyte Subsets/immunology , B-Lymphocyte Subsets/pathology , Gene Expression Regulation, Developmental/immunology , Genetic Predisposition to Disease , Lupus Erythematosus, Systemic/immunology , Membrane Glycoproteins/genetics , Toll-Like Receptor 7/genetics , Animals , Autoantibodies/adverse effects , B-Lymphocyte Subsets/metabolism , Disease Progression , Epistasis, Genetic/immunology , Female , Humans , Lupus Erythematosus, Systemic/genetics , Lupus Erythematosus, Systemic/pathology , Male , Membrane Glycoproteins/biosynthesis , Membrane Glycoproteins/physiology , Mice , Mice, 129 Strain , Mice, Inbred C57BL , Mice, Transgenic , Multiprotein Complexes/genetics , Multiprotein Complexes/immunology , Toll-Like Receptor 7/biosynthesis , Toll-Like Receptor 7/physiology , Transgenes/immunology
18.
J Heart Valve Dis ; 23(3): 259-70, 2014 May.
Article in English | MEDLINE | ID: mdl-25296447

ABSTRACT

BACKGROUND AND AIM OF THE STUDY: Native, allograft, xenograft and bioprosthetic semilunar valves are all susceptible to calcific degeneration. However, intrinsic differences in baseline calcium and phosphorus tissue concentrations within mammalian normal valve structural components (e.g., cusps, sinus, vessel wall) additionally subdivided by tripartite regions (e.g., right-, left- and non-coronary leaflets) have never been systematically measured and reported. It was originally hypothesized that variations in normative tissue concentrations of calcium and phosphorus may correspond to subsequent clinical patterns of acquired dystrophic calcification; decellularization was also expected to reduce the tissue concentrations of these elements. METHODS: Native semilunar valves were freshly harvested from 12 juvenile sheep. Half of the valves were decellularized (six aortic and six pulmonary), while the other valves were flash-frozen at -80 degrees C within minutes of euthanasia as native valves. Elemental calcium and phosphorus concentrations were measured in the great vessels, sinus walls and cusps using inductively coupled plasma optical emission spectrometry (ICP-OES), and analyzed with non-parametric statistical tests. RESULTS: Calcium concentrations (microg/mg tissue; median (range) were similar in aortic native cusps (0.37 (0.21)), sinus walls (0.37 (0.09)) and aorta (0.37 (0.08)) (p = 0.8298). Pulmonary calcium concentrations were similar in cusps, but 10-25% higher in the native sinus (p = 0.0018) and pulmonary artery (p < 0.0001) compared to analogous aortic structures. All cusps had higher phosphorus concentrations than their respective conduit tissues. No tripartite regional variations were observed. Decellularization did not reduce the calcium content of cusps, but removed 50-55% of vessel and sinus wall calcium. However, up to 85% of phosphorus was removed from all valve tissues (p < 0.001). CONCLUSION: There were no significant differences in normal tissue concentrations of calcium between aortic valve functional structures, and no semilunar tripartite regional differences in either semilunar valve complex. Thus, the distribution of baseline tissue calcium content of healthy young valves is not inherently predictive of selective or asymmetric anatomical patterns of valve degenerative calcification. Native semilunar cusps contain the highest phosphorus concentrations. Decellularization reduces all elemental concentrations except for cuspal calcium.


Subject(s)
Aortic Valve/chemistry , Calcium/analysis , Phosphorus/analysis , Pulmonary Valve/chemistry , Allografts , Animals , Aorta/chemistry , Aorta/cytology , Aortic Valve/cytology , Bioprosthesis , Calcinosis/prevention & control , Cryopreservation , DNA/isolation & purification , Heart Valve Prosthesis , Heterografts , Pulmonary Artery/chemistry , Pulmonary Artery/cytology , Pulmonary Valve/cytology , Sheep
19.
STAR Protoc ; 5(3): 103180, 2024 Jul 08.
Article in English | MEDLINE | ID: mdl-38980798

ABSTRACT

Mosquito behavioral assays are an important component in vector research and control tool development. Here, we present a protocol for rearing Anopheles mosquitoes, performing host-seeking behavioral bioassays, and collecting 3D flight tracks in a large wind tunnel. We describe steps for setting up host-seeking landing assays, both as a non-choice and as a dual-choice assay, and analyzing flight tracks. This protocol can be applied in the research of several behavioral traits, including nectar seeking, resting, mating, and oviposition behavior. For complete details on the use and execution of this protocol, please refer to Carnaghi et al.1.

20.
iScience ; 27(1): 108578, 2024 Jan 19.
Article in English | MEDLINE | ID: mdl-38155768

ABSTRACT

Malaria prevention relies on mosquito control interventions that use insecticides and exploit mosquito behavior. The rise of insecticide resistance and changing transmission dynamics urgently demand vector control innovation. To identify behavioral traits that could be incorporated into such tools, we investigated the flight and landing response of Anopheles coluzzii to human-like host cues. We show that landing rate is directly proportional to the surface area of thermal stimulus, whereas close-range orientation is modulated by both thermal and visual inputs. We modeled anopheline eye optics to theorize the distance at which visual targets can be detected under a range of conditions, and experimentally established mosquito preference for landing on larger targets, although landing density is greater on small targets. Target orientation does not affect landing rate; however, vertical targets can be resolved at greater distance than horizontal targets of the same size. Mosquito traps for vector control could be significantly enhanced by incorporating these features.

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