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1.
Environ DNA ; 6(1): 1-12, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38784600

RESUMO

The economic and methodological efficiencies of environmental DNA (eDNA) based survey approaches provide an unprecedented opportunity to assess and monitor aquatic environments. However, instances of inadequate communication from the scientific community about confidence levels, knowledge gaps, reliability, and appropriate parameters of eDNA-based methods have hindered their uptake in environmental monitoring programs and, in some cases, has created misperceptions or doubts in the management community. To help remedy this situation, scientists convened a session at the Second National Marine eDNA Workshop to discuss strategies for improving communications with managers. These include articulating the readiness of different eDNA applications, highlighting the strengths and limitations of eDNA tools for various applications or use cases, communicating uncertainties associated with specified uses transparently, and avoiding the exaggeration of exploratory and preliminary findings. Several key messages regarding implementation, limitations, and relationship to existing methods were prioritized. To be inclusive of the diverse managers, practitioners, and researchers, we and the other workshop participants propose the development of communication workflow plans, using RACI (Responsible, Accountable, Consulted, Informed) charts to clarify the roles of all pertinent individuals and parties and to minimize the chance for miscommunications. We also propose developing decision support tools such as Structured Decision-Making (SDM) to help balance the benefits of eDNA sampling with the inherent uncertainty, and developing an eDNA readiness scale to articulate the technological readiness of eDNA approaches for specific applications. These strategies will increase clarity and consistency regarding our understanding of the utility of eDNA-based methods, improve transparency, foster a common vision for confidently applying eDNA approaches, and enhance their benefit to the monitoring and assessment community.

2.
J Interpers Violence ; : 8862605241254140, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38770803

RESUMO

This research reports findings from a study to explore the efficacy of a video-based training with college students to determine the extent to which the training shifted student perceptions of hazing, increased willingness and ability to intervene in situations where hazing is occurring, and altered student perceptions of hazing social norms. The study included two experimental groups and a control group at each of the three data-gathering sessions at three U.S. universities. Each of the universities belonged to the Hazing Prevention Consortium and had demonstrated a willingness to prevent hazing on their campuses. The 17-minute hazing prevention documentary We Don't Haze, developed using a bystander intervention framework, was administered in two experimental conditions: video-only and video plus facilitated discussion. Participants (n = 318) were members of a leadership development program, resident advisors, and club sport athletes and were randomly assigned to one of the two treatment groups or the control group. Students who viewed the video-based training and students who viewed the video and engaged in a follow-up facilitated discussion significantly shifted their perceptions of hazing and indicated an increased willingness and ability to intervene and help others who are experiencing or have experienced hazing, compared to students who viewed a general leadership video. The results of this study indicate that the tested hazing prevention trainings-both the stand-alone video, We Don't Haze, and the video plus discussion-hold promise for strengthening knowledge of the full range of harm associated with hazing, while amplifying perceptions that support hazing prevention and diminishing perceptions that contribute to normalizing hazing.

3.
J Wildl Dis ; 59(4): 545-556, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37791744

RESUMO

Improving rapid detection methods for pathogens is important for research as we collectively aim to improve the health of ecosystems globally. In the northern hemisphere, the success of salmon (Oncorhynchus spp.) populations is vitally important to the larger marine, aquatic, and terrestrial ecosystems they inhabit. This has led to managers cultivating salmon in hatcheries and aquaculture to bolster their populations, but young salmon face many challenges, including diseases such as bacterial kidney disease (BKD). Early detection of the BKD causative agent, Renibacterium salmoninarum, is useful for managers to avoid outbreaks in hatcheries and aquaculture stocks to enable rapid treatment with targeted antibiotics. Isothermal amplification and CRIPSR-Cas12a systems may enable sensitive, relatively rapid, detection of target DNA molecules from environmental samples compared to quantitative PCR (qPCR) and culture methods. We used these technologies to develop a sensitive and specific rapid assay to detect R. salmoninarum from water samples using isothermal recombinase polymerase amplification (RPA) and an AsCas12a RNA-guided nuclease detection. The assay was specific to R. salmoninarum (0/10 co-occurring or closely related bacteria detected) and sensitive to 0.0128 pg/µL of DNA (approximately 20-40 copies/µL) within 10 min of Cas activity. This assay successfully detected R. salmoninarum environmental DNA in 14/20 water samples from hatcheries with known quantification for the pathogen via previous qPCR (70% of qPCR-positive samples). The RPA-CRISPR/AsCas12a assay had a limit of detection (LOD) of >10 copies/µL in the hatchery water samples and stochastic detection below 10 copies/µL, similar to but slightly higher than the qPCR assay. This LOD enables 37 C isothermal detection, potentially in the field, of biologically relevant levels of R. salmoninarum in water. Further research is needed to develop easy-to-use, cost-effective, sensitive RPA/CRISPR-AsCas12a assays for rapidly detecting low concentrations of wildlife pathogens in environmental samples.


Assuntos
DNA Ambiental , Doenças dos Peixes , Nefropatias , Micrococcaceae , Animais , Animais Selvagens , Sistemas CRISPR-Cas , Ecossistema , Micrococcaceae/genética , Nefropatias/microbiologia , Nefropatias/veterinária , Salmão/genética , Salmão/microbiologia , Água , Doenças dos Peixes/diagnóstico , Doenças dos Peixes/microbiologia
4.
Ecol Appl ; 33(8): e2914, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37641194

RESUMO

Environmental laws around the world require some version of an environmental-impact assessment surrounding construction projects and other discrete instances of human development. Information requirements for these assessments vary by jurisdiction, but nearly all require an analysis of the biological elements of ecosystems. Amplicon-sequencing-also called metabarcoding-of environmental DNA (eDNA) has made it possible to sample and amplify the genetic material of many species present in those environments, providing a tractable, powerful, and increasingly common way of doing environmental-impact analysis for development projects. Here, we analyze an 18-month time series of water samples taken before, during, and after two culvert removals in a salmonid-bearing freshwater stream. We also sampled multiple control streams to develop a robust background expectation against which to evaluate the impact of this discrete environmental intervention in the treatment stream. We generate calibrated, quantitative metabarcoding data from amplifying the 12s MiFish mtDNA locus and complementary species-specific quantitative PCR data to yield multispecies estimates of absolute eDNA concentrations across time, creeks, and sampling stations. We then use a linear mixed effects model to reveal patterns of eDNA concentrations over time, and to estimate the effects of the culvert removal on salmonids in the treatment creek. We focus our analysis on four common salmonid species: cutthroat trout (Oncorhynchus clarkii), coho salmon (Oncorhynchus kisutch), rainbow trout (Oncorhynchus mykiss), and sockeye salmon (Oncorhynchus nerka). We find that one culvert in the treatment creek seemed to have no impact while the second culvert had a large impact on fish passage. The construction itself seemed to have only transient effects on salmonid species during the two construction events. In the context of billions of dollars of court-mandated road culvert replacements taking place in Washington State, USA, our results suggest that culvert replacement can be conducted with only minimal impact of construction to key species of management concern. Furthermore, eDNA methods can be an effective and efficient approach for monitoring hundreds of culverts to prioritize culverts that are required to be replaced. More broadly, we demonstrate a rigorous, quantitative method for environmental-impact reporting using eDNA that is widely applicable in environments worldwide.


Assuntos
DNA Ambiental , Oncorhynchus kisutch , Oncorhynchus mykiss , Animais , Humanos , Ecossistema , Oncorhynchus mykiss/genética , Rios , Salmão
5.
Cell Chem Biol ; 30(10): 1191-1210.e20, 2023 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-37557181

RESUMO

KAT6A, and its paralog KAT6B, are histone lysine acetyltransferases (HAT) that acetylate histone H3K23 and exert an oncogenic role in several tumor types including breast cancer where KAT6A is frequently amplified/overexpressed. However, pharmacologic targeting of KAT6A to achieve therapeutic benefit has been a challenge. Here we describe identification of a highly potent, selective, and orally bioavailable KAT6A/KAT6B inhibitor CTx-648 (PF-9363), derived from a benzisoxazole series, which demonstrates anti-tumor activity in correlation with H3K23Ac inhibition in KAT6A over-expressing breast cancer. Transcriptional and epigenetic profiling studies show reduced RNA Pol II binding and downregulation of genes involved in estrogen signaling, cell cycle, Myc and stem cell pathways associated with CTx-648 anti-tumor activity in ER-positive (ER+) breast cancer. CTx-648 treatment leads to potent tumor growth inhibition in ER+ breast cancer in vivo models, including models refractory to endocrine therapy, highlighting the potential for targeting KAT6A in ER+ breast cancer.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/genética , Histonas/metabolismo , Histona Acetiltransferases/genética , Histona Acetiltransferases/metabolismo , Transdução de Sinais , Linhagem Celular Tumoral
6.
PLoS One ; 18(5): e0285674, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37167310

RESUMO

Metabarcoding is a powerful molecular tool for simultaneously surveying hundreds to thousands of species from a single sample, underpinning microbiome and environmental DNA (eDNA) methods. Deriving quantitative estimates of underlying biological communities from metabarcoding is critical for enhancing the utility of such approaches for health and conservation. Recent work has demonstrated that correcting for amplification biases in genetic metabarcoding data can yield quantitative estimates of template DNA concentrations. However, a major source of uncertainty in metabarcoding data stems from non-detections across technical PCR replicates where one replicate fails to detect a species observed in other replicates. Such non-detections are a special case of variability among technical replicates in metabarcoding data. While many sampling and amplification processes underlie observed variation in metabarcoding data, understanding the causes of non-detections is an important step in distinguishing signal from noise in metabarcoding studies. Here, we use both simulated and empirical data to 1) suggest how non-detections may arise in metabarcoding data, 2) outline steps to recognize uninformative data in practice, and 3) identify the conditions under which amplicon sequence data can reliably detect underlying biological signals. We show with both simulations and empirical data that, for a given species, the rate of non-detections among technical replicates is a function of both the template DNA concentration and species-specific amplification efficiency. Consequently, we conclude metabarcoding datasets are strongly affected by (1) deterministic amplification biases during PCR and (2) stochastic sampling of amplicons during sequencing-both of which we can model-but also by (3) stochastic sampling of rare molecules prior to PCR, which remains a frontier for quantitative metabarcoding. Our results highlight the importance of estimating species-specific amplification efficiencies and critically evaluating patterns of non-detection in metabarcoding datasets to better distinguish environmental signal from the noise inherent in molecular detections of rare targets.


Assuntos
Código de Barras de DNA Taxonômico , DNA Ambiental , Código de Barras de DNA Taxonômico/métodos , DNA/genética , Reação em Cadeia da Polimerase/métodos , Incerteza , Biodiversidade
7.
Health Educ Behav ; 50(5): 604-612, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-35707982

RESUMO

This case study examined community readiness in a cohort of U.S. universities. Drawing on the Community Readiness Model (CRM), the extent to which a campus was ready to implement a comprehensive hazing prevention plan was assessed. The study was designed to help build the knowledge base using the CRM to systematically assess the cohort's work to prevent hazing. Methods. Utilizing the CRM, key informants were interviewed. Interview data were scored using CRM rating scales and then coded following basic interpretive methods of qualitative analysis. Scores determined levels of readiness while data were analyzed for emergent themes related to a comprehensive approach to hazing prevention. Results. The CRM assessment revealed preplanning stages of readiness, meaning campus staff considered hazing prevention to be important and asking what should be done. Emergent themes that may strengthen and sustain hazing prevention in higher education are identified and discussed. Conclusions. Indications that the CRM may be useful for hazing prevention research and practice can contribute to the development of a knowledge base to support efficacy and assist campus communities in focusing their work while directing efforts toward higher levels of readiness.


Assuntos
Serviços de Saúde Comunitária , Pesquisa sobre Serviços de Saúde , Humanos , Universidades
8.
Ecology ; 104(2): e3906, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36320096

RESUMO

Amplicon-sequence data from environmental DNA (eDNA) and microbiome studies provide important information for ecology, conservation, management, and health. At present, amplicon-sequencing studies-known also as metabarcoding studies, in which the primary data consist of targeted, amplified fragments of DNA sequenced from many taxa in a mixture-struggle to link genetic observations to the underlying biology in a quantitative way, but many applications require quantitative information about the taxa or systems under scrutiny. As metabarcoding studies proliferate in ecology, it becomes more important to develop ways to make them quantitative to ensure that their conclusions are adequately supported. Here we link previously disparate sets of techniques for making such data quantitative, showing that the underlying polymerase chain reaction mechanism explains the observed patterns of amplicon data in a general way. By modeling the process through which amplicon-sequence data arise, rather than transforming the data post hoc, we show how to estimate the starting DNA proportions from a mixture of many taxa. We illustrate how to calibrate the model using mock communities and apply the approach to simulated data and a series of empirical examples. Our approach opens the door to improve the use of metabarcoding data in a wide range of applications in ecology, public health, and related fields.


Assuntos
Código de Barras de DNA Taxonômico , Microbiota , Código de Barras de DNA Taxonômico/métodos , DNA/genética , Ecologia , Biodiversidade
9.
Cell Death Dis ; 13(7): 627, 2022 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-35853868

RESUMO

Histone acetylation is essential for initiating and maintaining a permissive chromatin conformation and gene transcription. Dysregulation of histone acetylation can contribute to tumorigenesis and metastasis. Using inducible cre-recombinase and CRISPR/Cas9-mediated deletion, we investigated the roles of the histone lysine acetyltransferase TIP60 (KAT5/HTATIP) in human cells, mouse cells, and mouse embryos. We found that loss of TIP60 caused complete cell growth arrest. In the absence of TIP60, chromosomes failed to align in a metaphase plate during mitosis. In some TIP60 deleted cells, endoreplication occurred instead. In contrast, cell survival was not affected. Remarkably, the cell growth arrest caused by loss of TIP60 was independent of the tumor suppressors p53, INK4A and ARF. TIP60 was found to be essential for the acetylation of H2AZ, specifically at lysine 7. The mRNA levels of 6236 human and 8238 mouse genes, including many metabolism genes, were dependent on TIP60. Among the top 50 differentially expressed genes, over 90% were downregulated in cells lacking TIP60, supporting a role for TIP60 as a key co-activator of transcription. We propose a primary role of TIP60 in H2AZ lysine 7 acetylation and transcriptional activation, and that this fundamental role is essential for cell proliferation. Growth arrest independent of major tumor suppressors suggests TIP60 as a potential anti-cancer drug target.


Assuntos
Histonas , Lisina Acetiltransferase 5 , Lisina , Proteína Supressora de Tumor p53 , Acetilação , Animais , Pontos de Checagem do Ciclo Celular/fisiologia , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Histona Acetiltransferases/genética , Histona Acetiltransferases/metabolismo , Histonas/genética , Histonas/metabolismo , Humanos , Lisina/metabolismo , Lisina Acetiltransferase 5/deficiência , Lisina Acetiltransferase 5/genética , Lisina Acetiltransferase 5/metabolismo , Camundongos , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
10.
J Am Coll Health ; : 1-10, 2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35080477

RESUMO

Objective: The present report describes a comprehensive, public health approach to hazing prevention on a university campus and evaluates its impact over time. Participants: Two different surveys (PULSE and MASCOT) were administered to college undergraduate students, in April 2013 (PULSE n = 6,190; MASCOT n = 3,117) and March 2015 (PULSE n = 4,892; MASCOT n = 2,259). Methods: A public health model of hazing prevention was implemented between 2011-2015. The MASCOT Survey assessed experiences of hazing and non-hazing behaviors, and the PULSE Survey measured beliefs and perceptions of social norms related to hazing. Results: Survey results showed lower levels of hazing experiences reported by students in 2011-2015 compared to 2009-2013 and increased endorsement of a positive normative belief about hazing from 2013 to 2015. Conclusions: The findings represent the first measurable decrease in hazing associated with prevention efforts in the literature, though design limitations preclude clear causal inferences. The results suggest that the university's strategies may have been effective at reducing hazing, and therefore serve as an important step forward in the field of hazing prevention research.

11.
Malar J ; 20(1): 433, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34758840

RESUMO

BACKGROUND: Insecticide-treated nets and indoor residual spraying of insecticides are used as the vector control interventions in the fight against malaria. Measuring the actual amount of deposits of insecticides on bed nets and walls is essential for evaluating the quality and effectiveness of the intervention. A colorimetric "Test Kit" designed for use as a screening tool, able to detect the type II pyrethroids on fabrics and sprayed walls, was used for the first time to detect deltamethrin on long-lasting insecticidal nets (LLINs) deployed on Bioko Island, Equatorial Guinea. METHODS: LLINs were analysed using the colorimetric Test Kit performed in situ, which leads to the formation of an orange-red solution whose depth of colour indicates the amount of type II pyrethroid on the net. The kit results were validated by measuring the amount of extracted insecticide using high-performance liquid chromatography (HPLC) with diode array detection (DAD). RESULTS: Deltamethrin concentration was determined for 130 LLINs by HPLC-DAD. The deltamethrin concentration of these nets exhibited a significant decrease with the age of the net from 65 mg/m2 (< 12 months of use) to 31 mg/m2 (> 48 months; p < 0.001). Overall, 18% of the nets being used in households had < 15 mg/m2 of deltamethrin, thus falling into the "Fail" category as assessed by the colorimetric Test Kit. This was supported by determining the bio-efficacy of the nets using the WHO recommended cone bioassays. The Test Kit was field evaluated in situ and found to be rapid, accurate, and easy to use by people without laboratory training. The Test Kit was shown to have a reliable linear relationship between the depth of colour produced and deltamethrin concentration (R2 = 0.9135). CONCLUSION: This study shows that this colorimetric test was a reliable method to assess the insecticidal content of LLINs under operational conditions. The Test Kit provides immediate results and offers a rapid, inexpensive, field-friendly alternative to the complicated and costly methods such as HPLC and WHO cone bioassays which also need specialist staff. Thus, enabling National Malaria Control Programmes to gain access to effective and affordable monitoring tools for use in situ.


Assuntos
Colorimetria/normas , Mosquiteiros Tratados com Inseticida/normas , Inseticidas/análise , Nitrilas/análise , Piretrinas/análise , Animais , Bioensaio , Cromatografia Líquida de Alta Pressão , Guiné Equatorial , Feminino , Humanos , Ilhas , Reprodutibilidade dos Testes , Fatores de Tempo
12.
Sci Rep ; 11(1): 21273, 2021 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-34711868

RESUMO

Increasingly, researchers are using innovative methods to census marine life, including identification of environmental DNA (eDNA) left behind by organisms in the water column. However, little is understood about how eDNA is distributed in the ocean, given that organisms are mobile and that physical and biological processes can transport eDNA after release from a host. Particularly in the vast mesopelagic ocean where many species vertically migrate hundreds of meters diurnally, it is important to link the location at which eDNA was shed by a host organism to the location at which eDNA was collected in a water sample. Here, we present a one-dimensional mechanistic model to simulate the eDNA vertical distribution after its release and to compare the impact of key biological and physical parameters on the eDNA vertical and temporal distribution. The modeled vertical eDNA profiles allow us to quantify spatial and temporal variability in eDNA concentration and to identify the most important parameters to consider when interpreting eDNA signals. We find that the vertical displacement by advection, dispersion, and settling has limited influence on the eDNA distribution, and the depth at which eDNA is found is generally within tens of meters of the depth at which the eDNA was originally shed from the organism. Thus, using information about representative vertical migration patterns, eDNA concentration variability can be used to answer ecological questions about migrating organisms such as what depths species can be found in the daytime and nighttime and what percentage of individuals within a species diurnally migrate. These findings are critical both to advance the understanding of the vertical distribution of eDNA in the water column and to link eDNA detection to organism presence in the mesopelagic ocean as well as other aquatic environments.

13.
Sci Rep ; 11(1): 11809, 2021 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-34083578

RESUMO

The Cookiecutter shark (Isistius brasiliensis) is an ectoparasitic, mesopelagic shark that is known for removing plugs of tissue from larger prey, including teleosts, chondrichthyans, cephalopods, and marine mammals. Although this species is widely distributed throughout the world's tropical and subtropical oceanic waters, like many deep-water species, it remains very poorly understood due to its mesopelagic distribution. We used a suite of biochemical tracers, including stable isotope analysis (SIA), fatty acid analysis (FAA), and environmental DNA (eDNA), to investigate the trophic ecology of this species in the Central Pacific around Hawaii. We found that large epipelagic prey constituted a relatively minor part of the overall diet. Surprisingly, small micronektonic and forage species (meso- and epipelagic) are the most important prey group for Cookiecutter sharks across the studied size range (17-43 cm total length), with larger mesopelagic species or species that exhibit diel vertical migration also being important prey. These results were consistent across all the tracer techniques employed. Our results indicate that Cookiecutter sharks play a unique role in pelagic food webs, feeding on prey ranging from the largest apex predators to small, low trophic level species, in particular those that overlap with the depth distribution of the sharks throughout the diel cycle. We also found evidence of a potential shift in diet and/or habitat with size and season. Environmental DNA metabarcoding revealed new prey items for Cookiecutter sharks while also demonstrating that eDNA can be used to identify recent prey in stomachs frozen for extended periods. Integrating across chemical tracers is a powerful tool for investigating the ecology of elusive and difficult to study species, such as meso- and bathypelagic chondrichthyans, and can increase the amount of information gained from small sample sizes. Better resolving the foraging ecology of these mesopelagic predators is critical for effective conservation and management of these taxa and ecosystems, which are intrinsically vulnerable to overfishing and exploitation.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Ecossistema , Cadeia Alimentar , Tubarões , Animais , Biologia Computacional/métodos , DNA Ambiental , Ecologia , Meio Ambiente , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Masculino , Dinâmica Populacional , Traçadores Radioativos , Estações do Ano
14.
Eval Program Plann ; 75: 61-68, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31121390

RESUMO

Researchers argue that hazing can contribute to an abusive school climate and interfere with a positive learning environment for students. National efforts exist for establishing policies, protocols, evaluation, and education for students, administrators, and staff to prevent hazing at the college level, but this work has yet to be applied broadly in a high school context. In response to this gap, researchers implemented a pilot project at two high schools in Maine that consisted of hazing prevention training and assessment. This paper discusses the design, methods, and lessons learned through this collaborative, utilization-focused, and mixed-method training and evaluation with school personnel and high school student participants.


Assuntos
Bullying/prevenção & controle , Avaliação de Programas e Projetos de Saúde , Estudantes , Adolescente , Estudos de Avaliação como Assunto , Feminino , Humanos , Masculino , Projetos Piloto , Avaliação de Programas e Projetos de Saúde/métodos , Pesquisa Qualitativa
15.
BMJ Glob Health ; 2(4): e000409, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29082025

RESUMO

INTRODUCTION: Poor-quality artemisinin-containing antimalarials (ACAs), including falsified and substandard formulations, pose serious health concerns in malaria endemic countries. They can harm patients, contribute to the rise in drug resistance and increase the public's mistrust of health systems. Systematic assessment of drug quality is needed to gain knowledge on the prevalence of the problem, to provide Ministries of Health with evidence on which local regulators can take action. METHODS: We used three sampling approaches to purchase 677 ACAs from 278 outlets on Bioko Island, Equatorial Guinea as follows: convenience survey using mystery client (n=16 outlets, 31 samples), full island-wide survey using mystery client (n=174 outlets, 368 samples) and randomised survey using an overt sampling approach (n=88 outlets, 278 samples). The stated active pharmaceutical ingredients (SAPIs) were assessed using high-performance liquid chromatography and confirmed by mass spectrometry at three independent laboratories. RESULTS: Content analysis showed 91.0% of ACAs were of acceptable quality, 1.6% were substandard and 7.4% falsified. No degraded medicines were detected. The prevalence of medicines without the SAPIs was higher for ACAs purchased in the convenience survey compared with the estimates obtained using the full island-wide survey-mystery client and randomised-overt sampling approaches. Comparable results were obtained for full island survey-mystery client and randomised overt. However, the availability of purchased artesunate monotherapies differed substantially according to the sampling approach used (convenience, 45.2%; full island-wide survey-mystery client, 32.6%; random-overt sampling approach, 21.9%). Of concern is that 37.1% (n=62) of these were falsified. CONCLUSION: Falsified ACAs were found on Bioko Island, with the prevalence ranging between 6.1% and 16.1%, depending on the sampling method used. These findings underscore the vital need for national authorities to track the scale of ineffective medicines that jeopardise treatment of life-threatening diseases and value of a representative sampling approach to obtain/measure the true prevalence of poor-quality medicines.

16.
J Biol Chem ; 292(24): 9975-9987, 2017 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-28438838

RESUMO

Immunoglobulin E and its interactions with receptors FcϵRI and CD23 play a central role in allergic disease. Omalizumab, a clinically approved therapeutic antibody, inhibits the interaction between IgE and FcϵRI, preventing mast cell and basophil activation, and blocks IgE binding to CD23 on B cells and antigen-presenting cells. We solved the crystal structure of the complex between an omalizumab-derived Fab and IgE-Fc, with one Fab bound to each Cϵ3 domain. Free IgE-Fc adopts an acutely bent structure, but in the complex it is only partially bent, with large-scale conformational changes in the Cϵ3 domains that inhibit the interaction with FcϵRI. CD23 binding is inhibited sterically due to overlapping binding sites on each Cϵ3 domain. Studies of omalizumab Fab binding in solution demonstrate the allosteric basis for FcϵRI inhibition and, together with the structure, reveal how omalizumab may accelerate dissociation of receptor-bound IgE from FcϵRI, exploiting the intrinsic flexibility and allosteric potential of IgE.


Assuntos
Antiasmáticos/farmacologia , Imunoglobulina E/metabolismo , Modelos Moleculares , Omalizumab/farmacologia , Receptores de IgE/antagonistas & inibidores , Sítio Alostérico , Substituição de Aminoácidos , Cristalografia por Raios X , Transferência Ressonante de Energia de Fluorescência , Humanos , Imunoglobulina E/química , Imunoglobulina E/genética , Fragmentos Fab das Imunoglobulinas/química , Fragmentos Fab das Imunoglobulinas/genética , Fragmentos Fab das Imunoglobulinas/metabolismo , Fragmentos Fab das Imunoglobulinas/farmacologia , Fragmentos Fc das Imunoglobulinas/química , Fragmentos Fc das Imunoglobulinas/genética , Fragmentos Fc das Imunoglobulinas/metabolismo , Fragmentos Fc das Imunoglobulinas/farmacologia , Omalizumab/química , Omalizumab/genética , Omalizumab/metabolismo , Maleabilidade , Mutação Puntual , Conformação Proteica , Domínios e Motivos de Interação entre Proteínas , Redobramento de Proteína , Receptores de IgE/química , Receptores de IgE/metabolismo , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Recombinantes de Fusão/farmacologia , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacologia , Solubilidade , Ressonância de Plasmônio de Superfície
17.
Am J Trop Med Hyg ; 96(5): 1117-1123, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28219992

RESUMO

AbstractPoor-quality medicines are a major problem for health-care systems in resource-poor settings as identifying falsified medicines requires a complex laboratory infrastructure such as a Medicines Quality Control Laboratory. We report here an evaluation of a low-cost, handheld near-infrared spectrometer (NIRS) device by analyzing a library of artemisinin-based combination therapy (ACT) medicines to determine its usefulness as a drug-screening tool. The "SCiO" research prototype device was used to collect NIR spectra of a library of ACT and artesunate monotherapy medicine samples previously collected in Bioko Island and Equatorial Guinea and Kintampo, Ghana. The quality of these samples had been categorized as falsified, substandard, and quality assured based on the amount of stated active pharmaceutical ingredients detected using high-performance liquid chromatography photodiode array. Numerical analyses were performed on the NIR spectra to assess the usefulness of NIR to identify falsified and substandard medicines. The NIRS device was successful at detecting falsified medicines in all cases where the library contained both quality assured and falsified medicines of the same stated brand of medicines. The NIRS device was successful at identifying substandard amounts of artesunate but not amodiaquine in the ACT samples (N = 15) of artesunate-amodiaquine. This work reveals that this low-cost, portable NIRS device is promising for screening ACTs for falsified samples and could enable widespread drug screening at all points of the health system.


Assuntos
Amodiaquina/análise , Antimaláricos/análise , Artemisininas/análise , Computadores de Mão , Medicamentos Falsificados/análise , Artesunato , Cromatografia Líquida de Alta Pressão , Combinação de Medicamentos , Contaminação de Medicamentos/prevenção & controle , Guiné Equatorial , Gana , Humanos , Aplicativos Móveis , Controle de Qualidade , Sensibilidade e Especificidade , Espectrofotometria Infravermelho/instrumentação , Espectrofotometria Infravermelho/métodos
18.
Biodivers Data J ; (4): e8051, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27660527

RESUMO

BACKGROUND: The cicadas of the Indian subcontinent, like many other insects in the region, have remained understudied since the early part of the 20th Century, and await modern taxonomic, systematic and phylogenetic treatment. This paper presents an updated systematic catalogue of cicadas (Hemiptera: Cicadidae) from India, Bangladesh, Bhutan, Myanmar, Nepal and Sri Lanka, the first in over a century. NEW INFORMATION: This paper treats 281 species, including: India and Bangladesh (189 species), Bhutan (19 species), Myanmar (81 species), Nepal (46 species) and Sri Lanka (22 species). For each species all recognized junior synonyms are included with information on the type material and additional specimens where relevant. The global distributional range and notes on the taxonomy of each species are included where appropriate. Two lists are provided: (1) species known to occur in India and Bangladesh (treated as a geographic unit), Bhutan, Myanmar, Nepal and Sri Lanka; and (2) species previously listed from these countries in error. A bibliography of species descriptions is provided, with the papers containing the original descriptions provided where copyright allows.

19.
Am J Trop Med Hyg ; 94(5): 993-1001, 2016 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-26951346

RESUMO

Poor quality antimalarials, including falsified, substandard, and degraded drugs, are a serious health concern in malaria-endemic countries. Guidelines are lacking on how to distinguish between substandard and degraded drugs. "Forced degradation" in an oven was carried out on three common artemisinin-based combination therapy (ACT) brands to detect products of degradation using liquid chromatography mass spectrometry and help facilitate classification of degraded drugs. "Natural aging" of 2,880 tablets each of ACTs artemether/lumefantrine and artesunate/amodiaquine was undertaken to evaluate their long-term stability in tropical climates. Samples were aged in the presence and absence of light on-site in Ghana and in a stability chamber (London), removed at regular intervals, and analyzed to determine loss of the active pharmaceutical ingredients (APIs) over time and detect products of degradation. Loss of APIs in naturally aged tablets (both in Ghana and the pharmaceutical stability chamber) was 0-7% over 3 years (∼12 months beyond expiry) with low levels of degradation products detected. Using this developed methodology, it was found that a quarter of ACTs purchased in Enugu, Nigeria (concurrent study), that would have been classified as substandard, were in fact degraded. Presence of degradation products together with evidence of insufficient APIs can be used to classify drugs as degraded.


Assuntos
Antimaláricos/química , Artemisininas/química , Temperatura Alta , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Fatores de Tempo , Clima Tropical
20.
PLoS One ; 10(5): e0125577, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26018221

RESUMO

BACKGROUND: Artemisinin-based combination therapies are recommended by the World Health Organisation (WHO) as first-line treatment for Plasmodium falciparum malaria, yet medication must be of good quality for efficacious treatment. A recent meta-analysis reported 35% (796/2,296) of antimalarial drug samples from 21 Sub-Saharan African countries, purchased from outlets predominantly using convenience sampling, failed chemical content analysis. We used three sampling strategies to purchase artemisinin-containing antimalarials (ACAs) in Enugu metropolis, Nigeria, and compared the resulting quality estimates. METHODS: ACAs were purchased using three sampling approaches--convenience, mystery clients and overt, within a defined area and sampling frame in Enugu metropolis. The active pharmaceutical ingredients were assessed using high-performance liquid chromatography and confirmed by mass spectrometry at three independent laboratories. Results were expressed as percentage of APIs stated on the packaging and used to categorise each sample as acceptable quality, substandard, degraded, or falsified. RESULTS: Content analysis of 3024 samples purchased from 421 outlets using convenience (n=200), mystery (n=1,919) and overt (n=905) approaches, showed overall 90.8% ACAs to be of acceptable quality, 6.8% substandard, 1.3% degraded and 1.2% falsified. Convenience sampling yielded a significantly higher prevalence of poor quality ACAs, but was not evident by the mystery and overt sampling strategies both of which yielded results that were comparable between each other. Artesunate (n=135; 4 falsified) and dihydroartemisinin (n=14) monotherapy tablets, not recommended by WHO, were also identified. CONCLUSION: Randomised sampling identified fewer falsified ACAs than previously reported by convenience approaches. Our findings emphasise the need for specific consideration to be given to sampling frame and sampling approach if representative information on drug quality is to be obtained.


Assuntos
Antimaláricos/normas , Antimaláricos/uso terapêutico , Antimaláricos/química , Artemisininas/análise , Artesunato , Cromatografia Líquida de Alta Pressão , Humanos , Malária Falciparum/tratamento farmacológico , Nigéria , Farmácias , Setor Privado , Logradouros Públicos , Controle de Qualidade , Fatores de Risco , Comprimidos
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