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1.
Molecules ; 28(7)2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-37049729

RESUMO

In recent years, there have been significant developments in plant proteins production for meat and fish analogues. Some of the key developments include the use of new plant protein sources such as soy, legumes, grains, potatoes, and seaweed, as well as insect proteins, leaf proteins, mushrooms, and microbial proteins. Furthermore, to improve the technological and functional properties of plant proteins, they can be subjected to traditional and unconventional treatments such as chemical (glycosylation, deamidation, phosphorylation, and acylation), physical (pulsed electric fields, ultrasound, high hydrostatic pressure, dynamic high-pressure treatment, and cold plasma), and biological (fermentation and enzymatic modification). To obtain the high quality and the desired texture of the food product, other ingredients besides proteins, such as water, fat, flavors, binders, dyes, vitamins, minerals, and antioxidants, also have to be used. The final product can be significantly influenced by the matrix composition, variety of ingredients, and water content, with the type of ingredients playing a role in either enhancing or constraining the desired texture of the food. There are several types of technologies used for meat and fish analogues production, including extrusion, shear cell technology, spinning, 3D printing, and others. Overall, the technologies used for meat and fish analogues production are constantly evolving as new innovations are developed and existing methods are improved. These developments have led to the creation of plant-based products that have a similar texture, taste, and nutritional profile to meat and fish, making them more appealing to consumers seeking alternatives to animal-based products.


Assuntos
Produtos da Carne , Proteínas de Plantas , Animais , Proteínas de Plantas/química , Carne/análise , Manipulação de Alimentos , Antioxidantes , Verduras
2.
Int J Mol Sci ; 24(2)2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36675037

RESUMO

Regulatory T cells (Tregs) play an important role in maintaining immune tolerance and homeostasis by modulating how the immune system is activated. Several studies have documented the critical role of Tregs in suppressing the functions of effector T cells and antigen-presenting cells. Under certain conditions, Tregs can lose their suppressive capability, leading to a compromised immune system. For example, mutations in the Treg transcription factor, Forkhead box P3 (FOXP3), can drive the development of autoimmune diseases in multiple organs within the body. Furthermore, mutations leading to a reduction in the numbers of Tregs or a change in their function facilitate autoimmunity, whereas an overabundance can inhibit anti-tumor and anti-pathogen immunity. This review discusses the characteristics of Tregs and their mechanism of action in select autoimmune skin diseases, transplantation, and skin cancer. We also examine the potential of Tregs-based cellular therapies in autoimmunity.


Assuntos
Doenças Autoimunes , Dermatopatias , Neoplasias Cutâneas , Humanos , Linfócitos T Reguladores , Doenças Autoimunes/etiologia , Doenças Autoimunes/terapia , Autoimunidade , Neoplasias Cutâneas/etiologia , Neoplasias Cutâneas/terapia , Dermatopatias/etiologia , Dermatopatias/terapia , Fatores de Transcrição Forkhead
3.
STAR Protoc ; 4(1): 101932, 2023 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-36574340

RESUMO

We present a protocol to detect extracellular traps (ETs) induced by Cutibacterium acnes in cultured TH17 clones. We first describe the isolation of C. acnes-specific TH17 clones by sterile cell sorting. We then detail the in vitro induction of ETs in TH17 clones stimulated by C. acnes and the imaging of released ETs using scanning electron microscopy. This protocol can be applied to the study of other ETs released by other T cell subsets. For complete details on the use and execution of this protocol, please refer to Agak et al. (2021).1.


Assuntos
Armadilhas Extracelulares , Linfócitos T , Humanos , Microscopia Eletrônica de Varredura , Separação Celular , Linfócitos T CD4-Positivos
4.
Proc Biol Sci ; 289(1970): 20220042, 2022 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-35259992

RESUMO

Adaptive radiation is an important mechanism of organismal diversification and can be triggered by new ecological opportunities. Although poorly studied in this regard, parasites are an ideal group in which to study adaptive radiations because of their close associations with host species. Both experimental and comparative studies suggest that the ectoparasitic wing lice of pigeons and doves have adaptively radiated, leading to differences in body size and overall coloration. Here, we show that long-distance dispersal by dove hosts was central to parasite diversification because it provided new ecological opportunities for parasites to speciate after host-switching. We further show that among extant parasite lineages host-switching decreased over time, with cospeciation becoming the more dominant mode of parasite speciation. Taken together, our results suggest that host dispersal, followed by host-switching, provided novel ecological opportunities that facilitated adaptive radiation by parasites.


Assuntos
Parasitos , Ftirápteros , Animais , Columbidae , Interações Hospedeiro-Parasita , Filogenia
5.
Int J Mol Sci ; 23(2)2022 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-35054800

RESUMO

Hypoxic-Ischemic Encephalopathy (HIE) in the brain is the leading cause of morbidity and mortality in neonates and can lead to irreparable tissue damage and cognition. Thus, investigating key mediators of the HI response to identify points of therapeutic intervention has significant clinical potential. Brain repair after HI requires highly coordinated injury responses mediated by cell-derived extracellular vesicles (EVs). Studies show that stem cell-derived EVs attenuate the injury response in ischemic models by releasing neuroprotective, neurogenic, and anti-inflammatory factors. In contrast to 2D cell cultures, we successfully isolated and characterized EVs from whole brain rat tissue (BEV) to study the therapeutic potential of endogenous EVs. We showed that BEVs decrease cytotoxicity in an ex vivo oxygen glucose deprivation (OGD) brain slice model of HI in a dose- and time-dependent manner. The minimum therapeutic dosage was determined to be 25 µg BEVs with a therapeutic application time window of 4-24 h post-injury. At this therapeutic dosage, BEV treatment increased anti-inflammatory cytokine expression. The morphology of microglia was also observed to shift from an amoeboid, inflammatory phenotype to a restorative, anti-inflammatory phenotype between 24-48 h of BEV exposure after OGD injury, indicating a shift in phenotype following BEV treatment. These results demonstrate the use of OWH brain slices to facilitate understanding of BEV activity and therapeutic potential in complex brain pathologies for treating neurological injury in neonates.


Assuntos
Isquemia Encefálica/terapia , Encéfalo/metabolismo , Encéfalo/patologia , Vesículas Extracelulares/metabolismo , Animais , Animais Recém-Nascidos , Biomarcadores/metabolismo , Forma Celular , Sobrevivência Celular , Vesículas Extracelulares/ultraestrutura , Feminino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley
6.
Ecohealth ; 18(4): 421-428, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34970712

RESUMO

We investigated the prevalence of coronaviruses in 44 bats from four families in northeastern Eswatini using high-throughput sequencing of fecal samples. We found evidence of coronaviruses in 18% of the bats. We recovered full or near-full-length genomes from two bat species: Chaerephon pumilus and Afronycteris nana, as well as additional coronavirus genome fragments from C. pumilus, Epomophorus wahlbergi, Mops condylurus, and Scotophilus dinganii. All bats from which we detected coronaviruses were captured leaving buildings or near human settlements, demonstrating the importance of continued surveillance of coronaviruses in bats to better understand the prevalence, diversity, and potential risks for spillover.


Assuntos
Quirópteros , Infecções por Coronavirus , Coronavirus , Metagenômica , Animais , Quirópteros/virologia , Coronavirus/genética , Infecções por Coronavirus/veterinária , Essuatíni , Variação Genética , Genoma Viral , Filogenia
7.
Nat Genet ; 52(9): 891-897, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32807987

RESUMO

Extrachromosomal DNA (ecDNA) amplification promotes intratumoral genetic heterogeneity and accelerated tumor evolution1-3; however, its frequency and clinical impact are unclear. Using computational analysis of whole-genome sequencing data from 3,212 cancer patients, we show that ecDNA amplification frequently occurs in most cancer types but not in blood or normal tissue. Oncogenes were highly enriched on amplified ecDNA, and the most common recurrent oncogene amplifications arose on ecDNA. EcDNA amplifications resulted in higher levels of oncogene transcription compared to copy number-matched linear DNA, coupled with enhanced chromatin accessibility, and more frequently resulted in transcript fusions. Patients whose cancers carried ecDNA had significantly shorter survival, even when controlled for tissue type, than patients whose cancers were not driven by ecDNA-based oncogene amplification. The results presented here demonstrate that ecDNA-based oncogene amplification is common in cancer, is different from chromosomal amplification and drives poor outcome for patients across many cancer types.


Assuntos
Cromossomos/genética , DNA/genética , Amplificação de Genes/genética , Neoplasias/genética , Oncogenes/genética , Linhagem Celular Tumoral , Cromatina/genética , Humanos
9.
Nat Commun ; 11(1): 550, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31992716

RESUMO

Many cellular models aimed at elucidating cancer biology do not recapitulate pathobiology including tumor heterogeneity, an inherent feature of cancer that underlies treatment resistance. Here we introduce a cancer modeling paradigm using genetically engineered human pluripotent stem cells (hiPSCs) that captures authentic cancer pathobiology. Orthotopic engraftment of the neural progenitor cells derived from hiPSCs that have been genome-edited to contain tumor-associated genetic driver mutations revealed by The Cancer Genome Atlas project for glioblastoma (GBM) results in formation of high-grade gliomas. Similar to patient-derived GBM, these models harbor inter-tumor heterogeneity resembling different GBM molecular subtypes, intra-tumor heterogeneity, and extrachromosomal DNA amplification. Re-engraftment of these primary tumor neurospheres generates secondary tumors with features characteristic of patient samples and present mutation-dependent patterns of tumor evolution. These cancer avatar models provide a platform for comprehensive longitudinal assessment of human tumor development as governed by molecular subtype mutations and lineage-restricted differentiation.


Assuntos
Engenharia Genética , Glioblastoma/genética , Glioblastoma/patologia , Células-Tronco Pluripotentes/patologia , Animais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Diferenciação Celular , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica , Genoma , Glioblastoma/metabolismo , Glioma/genética , Glioma/patologia , Humanos , Camundongos , Camundongos SCID , Mutação , Transplante de Neoplasias , Células-Tronco Neoplásicas/patologia , Neurofibromina 1/genética , PTEN Fosfo-Hidrolase/genética , Transplante Heterólogo , Proteína Supressora de Tumor p53/genética
10.
Nat Commun ; 10(1): 392, 2019 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-30674876

RESUMO

Focal oncogene amplification and rearrangements drive tumor growth and evolution in multiple cancer types. We present AmpliconArchitect (AA), a tool to reconstruct the fine structure of focally amplified regions using whole genome sequencing (WGS) and validate it extensively on multiple simulated and real datasets, across a wide range of coverage and copy numbers. Analysis of AA-reconstructed amplicons in a pan-cancer dataset reveals many novel properties of copy number amplifications in cancer. These findings support a model in which focal amplifications arise due to the formation and replication of extrachromosomal DNA. Applying AA to 68 viral-mediated cancer samples, we identify a large fraction of amplicons with specific structural signatures suggestive of hybrid, human-viral extrachromosomal DNA. AA reconstruction, integrated with metaphase fluorescence in situ hybridization (FISH) and PacBio sequencing on the cell-line UPCI:SCC090 confirm the extrachromosomal origin and fine structure of a Forkhead box E1 (FOXE1)-containing hybrid amplicon.


Assuntos
Amplificação de Genes , Neoplasias/genética , Algoritmos , Linhagem Celular , Linhagem Celular Tumoral , Duplicação Cromossômica , Cromossomos Humanos/genética , Computadores Moleculares , Fatores de Transcrição Forkhead/genética , Genes Virais , Humanos , Hibridização in Situ Fluorescente
11.
PeerJ ; 7: e6142, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30627489

RESUMO

Aligning sequences for phylogenetic analysis (multiple sequence alignment; MSA) is an important, but increasingly computationally expensive step with the recent surge in DNA sequence data. Much of this sequence data is publicly available, but can be extremely fragmentary (i.e., a combination of full genomes and genomic fragments), which can compound the computational issues related to MSA. Traditionally, alignments are produced with automated algorithms and then checked and/or corrected "by eye" prior to phylogenetic inference. However, this manual curation is inefficient at the data scales required of modern phylogenetics and results in alignments that are not reproducible. Recently, methods have been developed for fully automating alignments of large data sets, but it is unclear if these methods produce alignments that result in compatible phylogenies when compared to more traditional alignment approaches that combined automated and manual methods. Here we use approximately 33,000 publicly available sequences from the hepatitis B virus (HBV), a globally distributed and rapidly evolving virus, to compare different alignment approaches. Using one data set comprised exclusively of whole genomes and a second that also included sequence fragments, we compared three MSA methods: (1) a purely automated approach using traditional software, (2) an automated approach including by eye manual editing, and (3) more recent fully automated approaches. To understand how these methods affect phylogenetic results, we compared resulting tree topologies based on these different alignment methods using multiple metrics. We further determined if the monophyly of existing HBV genotypes was supported in phylogenies estimated from each alignment type and under different statistical support thresholds. Traditional and fully automated alignments produced similar HBV phylogenies. Although there was variability between branch support thresholds, allowing lower support thresholds tended to result in more differences among trees. Therefore, differences between the trees could be best explained by phylogenetic uncertainty unrelated to the MSA method used. Nevertheless, automated alignment approaches did not require human intervention and were therefore considerably less time-intensive than traditional approaches. Because of this, we conclude that fully automated algorithms for MSA are fully compatible with older methods even in extremely difficult to align data sets. Additionally, we found that most HBV diagnostic genotypes did not correspond to evolutionarily-sound groups, regardless of alignment type and support threshold. This suggests there may be errors in genotype classification in the database or that HBV genotypes may need a revision.

12.
Biol Lett ; 14(5)2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29794007

RESUMO

The diversification of parasite groups often occurs at the same time as the diversification of their hosts. However, most studies demonstrating this concordance only examine single host-parasite groups. Multiple diverse lineages of ectoparasitic lice occur across both birds and mammals. Here, we describe the evolutionary history of lice based on analyses of 1107 single-copy orthologous genes from sequenced genomes of 46 species of lice. We identify three major diverse groups of lice: one exclusively on mammals, one almost exclusively on birds and one on both birds and mammals. Each of these groups radiated just after the Cretaceous-Paleogene (K-Pg) boundary, the time of the mass extinction event of the dinosaurs and rapid diversification of most of the modern lineages of birds and mammals.


Assuntos
Evolução Biológica , Aves/parasitologia , Mamíferos/parasitologia , Ftirápteros/classificação , Animais , Genoma de Inseto/genética , Interações Hospedeiro-Parasita , Ftirápteros/genética , Filogenia
13.
Nucleic Acids Res ; 46(7): 3309-3325, 2018 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-29579309

RESUMO

The integration of viral sequences into the host genome is an important driver of tumorigenesis in many viral mediated cancers, notably cervical cancer and hepatocellular carcinoma. We present ViFi, a computational method that combines phylogenetic methods with reference-based read mapping to detect viral integrations. In contrast with read-based reference mapping approaches, ViFi is faster, and shows high precision and sensitivity on both simulated and biological data, even when the integrated virus is a novel strain or highly mutated. We applied ViFi to matched genomic and mRNA data from 68 cervical cancer samples from TCGA and found high concordance between the two. Surprisingly, viral integration resulted in a dramatic transcriptional upregulation in all proximal elements, including LINEs and LTRs that are not normally transcribed. This upregulation is highly correlated with the presence of a viral gene fused with a downstream human element. Moreover, genomic rearrangements suggest the formation of apparent circular extrachromosomal (ecDNA) human-viral structures. Our results suggest the presence of apparent small circular fusion viral/human ecDNA, which correlates with indiscriminate and unregulated expression of proximal genomic elements, potentially contributing to the pathogenesis of HPV-associated cervical cancers. ViFi is available at https://github.com/namphuon/ViFi.


Assuntos
DNA Circular/química , Papillomaviridae/genética , Neoplasias do Colo do Útero/genética , Integração Viral/genética , Biologia Computacional/instrumentação , DNA Circular/genética , DNA Viral/química , DNA Viral/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Genoma Humano/genética , Humanos , Elementos Nucleotídeos Longos e Dispersos/genética , Papillomaviridae/patogenicidade , RNA Mensageiro/química , RNA Mensageiro/genética , Sequências Repetidas Terminais/genética , Transcrição Gênica , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/virologia
14.
Mol Biol Evol ; 34(7): 1743-1757, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28419279

RESUMO

Insects with restricted diets rely on symbiotic bacteria to provide essential metabolites missing in their diet. The blood-sucking lice are obligate, host-specific parasites of mammals and are themselves host to symbiotic bacteria. In human lice, these bacterial symbionts supply the lice with B-vitamins. Here, we sequenced the genomes of symbiotic and heritable bacterial of human, chimpanzee, gorilla, and monkey lice and used phylogenomics to investigate their evolutionary relationships. We find that these symbionts have a phylogenetic history reflecting the louse phylogeny, a finding contrary to previous reports of symbiont replacement. Examination of the highly reduced symbiont genomes (0.53-0.57 Mb) reveals much of the genomes are dedicated to vitamin synthesis. This is unchanged in the smallest symbiont genome and one that appears to have been reorganized. Specifically, symbionts from human lice, chimpanzee lice, and gorilla lice carry a small plasmid that encodes synthesis of vitamin B5, a vitamin critical to the bacteria-louse symbiosis. This plasmid is absent in an old world monkey louse symbiont, where this pathway is on its primary chromosome. This suggests the unique genomic configuration brought about by the plasmid is not essential for symbiosis, but once obtained, it has persisted for up to 25 My. We also find evidence that human, chimpanzee, and gorilla louse endosymbionts have lost a pathway for synthesis of vitamin B1, whereas the monkey louse symbiont has retained this pathway. It is unclear whether these changes are adaptive, but they may point to evolutionary responses of louse symbionts to shifts in primate biology.


Assuntos
Anoplura/genética , Pediculus/genética , Simbiose/genética , Animais , Bactérias/genética , Evolução Biológica , Evolução Molecular , Genoma Bacteriano , Genômica/métodos , Hominidae/genética , Humanos , Pan troglodytes/genética , Filogenia , Plasmídeos/genética , Primatas/genética , Análise de Sequência de DNA/métodos
15.
Syst Biol ; 66(6): 896-911, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-28108601

RESUMO

Parasitic "wing lice" (Phthiraptera: Columbicola) and their dove and pigeon hosts are a well-recognized model system for coevolutionary studies at the intersection of micro- and macroevolution. Selection on lice in microevolutionary time occurs as pigeons and doves defend themselves against lice by preening. In turn, behavioral and morphological adaptations of the lice improve their ability to evade host defense. Over macroevolutionary time wing lice tend to cospeciate with their hosts; yet, some species of Columbicola have switched to new host species. Understanding the ecological and evolutionary factors that influence coadaptation and codiversification in this system will substantially improve our understanding of coevolution in general. However, further work is hampered by the lack of a robust phylogenetic framework for Columbicola spp. and their hosts. Previous attempts to resolve the phylogeny of Columbicola based on sequences from a few genes provided limited support. Here, we apply a new approach, target restricted assembly, to assemble 977 orthologous gene sequences from whole-genome sequence data generated from very small, ethanol-preserved specimens, representing up to 61 species of wing lice. Both concatenation and coalescent methods were used to estimate the species tree. These two approaches yielded consistent and well-supported trees with 90% of all relationships receiving 100% support, which is a substantial improvement over previous studies. We used this new phylogeny to show that biogeographic ranges are generally conserved within clades of Columbicola wing lice. Limited inconsistencies are probably attributable to intercontinental dispersal of hosts, and host switching by some of the lice. [aTRAM; coalescent; coevolution; concatenation; species tree.].


Assuntos
Genoma/genética , Ftirápteros/classificação , Ftirápteros/genética , Filogenia , Animais , Columbidae/parasitologia , Especificidade de Hospedeiro , Interações Hospedeiro-Parasita , Ftirápteros/fisiologia
16.
Syst Biol ; 66(5): 786-798, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28123117

RESUMO

Novel sequencing technologies are rapidly expanding the size of data sets that can be applied to phylogenetic studies. Currently the most commonly used phylogenomic approaches involve some form of genome reduction. While these approaches make assembling phylogenomic data sets more economical for organisms with large genomes, they reduce the genomic coverage and thereby the long-term utility of the data. Currently, for organisms with moderate to small genomes ($<$1000 Mbp) it is feasible to sequence the entire genome at modest coverage ($10-30\times$). Computational challenges for handling these large data sets can be alleviated by assembling targeted reads, rather than assembling the entire genome, to produce a phylogenomic data matrix. Here we demonstrate the use of automated Target Restricted Assembly Method (aTRAM) to assemble 1107 single-copy ortholog genes from whole genome sequencing of sucking lice (Anoplura) and out-groups. We developed a pipeline to extract exon sequences from the aTRAM assemblies by annotating them with respect to the original target protein. We aligned these protein sequences with the inferred amino acids and then performed phylogenetic analyses on both the concatenated matrix of genes and on each gene separately in a coalescent analysis. Finally, we tested the limits of successful assembly in aTRAM by assembling 100 genes from close- to distantly related taxa at high to low levels of coverage.Both the concatenated analysis and the coalescent-based analysis produced the same tree topology, which was consistent with previously published results and resolved weakly supported nodes. These results demonstrate that this approach is successful at developing phylogenomic data sets from raw genome sequencing reads. Further, we found that with coverages above $5-10\times$, aTRAM was successful at assembling 80-90% of the contigs for both close and distantly related taxa. As sequencing costs continue to decline, we expect full genome sequencing will become more feasible for a wider array of organisms, and aTRAM will enable mining of these genomic data sets for an extensive variety of applications, including phylogenomics. [aTRAM; gene assembly; genome sequencing; phylogenomics.].


Assuntos
Classificação/métodos , Genômica/métodos , Filogenia , Análise de Sequência
17.
Emerg Microbes Infect ; 5(8): e90, 2016 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-27530749

RESUMO

Outbreaks of zoonotic diseases in humans and livestock are not uncommon, and an important component in containment of such emerging viral diseases is rapid and reliable diagnostics. Such methods are often PCR-based and hence require the availability of sequence data from the pathogen. Rattus norvegicus (R. norvegicus) is a known reservoir for important zoonotic pathogens. Transmission may be direct via contact with the animal, for example, through exposure to its faecal matter, or indirectly mediated by arthropod vectors. Here we investigated the viral content in rat faecal matter (n=29) collected from two continents by analyzing 2.2 billion next-generation sequencing reads derived from both DNA and RNA. Among other virus families, we found sequences from members of the Picornaviridae to be abundant in the microbiome of all the samples. Here we describe the diversity of the picornavirus-like contigs including near-full-length genomes closely related to the Boone cardiovirus and Theiler's encephalomyelitis virus. From this study, we conclude that picornaviruses within R. norvegicus are more diverse than previously recognized. The virome of R. norvegicus should be investigated further to assess the full potential for zoonotic virus transmission.


Assuntos
Reservatórios de Doenças , Fezes/virologia , Microbioma Gastrointestinal , Variação Genética , Genoma Viral , Infecções por Picornaviridae/epidemiologia , Picornaviridae/genética , Ratos/virologia , Sequência de Aminoácidos , Animais , Dinamarca/epidemiologia , Sequenciamento de Nucleotídeos em Larga Escala , Hong Kong/epidemiologia , Humanos , Malásia/epidemiologia , Metagenômica , Filogenia , Picornaviridae/classificação , Picornaviridae/isolamento & purificação , Infecções por Picornaviridae/transmissão , RNA Viral , Proteínas Virais/química , Proteínas Virais/genética , Zoonoses
18.
Inj Prev ; 22(4): 233-8, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26728008

RESUMO

BACKGROUND: Vietnam's 2007 comprehensive motorcycle helmet policy increased helmet use from about 30% of riders to about 93%. We aimed to simulate the effect that this legislation might have on: (a) road traffic deaths and non-fatal injuries, (b) individuals' direct acute care injury treatment costs, (c) individuals' income losses from missed work and (d) individuals' protection against medical impoverishment. METHODS AND FINDINGS: We used published secondary data from the literature to perform a retrospective extended cost-effectiveness analysis simulation study of the policy. Our model indicates that in the year following its introduction a helmet policy employing standard helmets likely prevented approximately 2200 deaths and 29 000 head injuries, saved individuals US$18 million in acute care costs and averted US$31 million in income losses. From a societal perspective, such a comprehensive helmet policy would have saved $11 000 per averted death or $830 per averted non-fatal injury. In terms of financial risk protection, traffic injury is so expensive to treat that any injury averted would necessarily entail a case of catastrophic health expenditure averted. CONCLUSIONS: The high costs associated with traffic injury suggest that helmet legislation can decrease the burden of out-of-pocket payments and reduced injuries decrease the need for access to and coverage for treatment, allowing the government and individuals to spend resources elsewhere. These findings suggest that comprehensive motorcycle helmet policies should be adopted by low-income and middle-income countries where motorcycles are pervasive yet helmet use is less common.


Assuntos
Acidentes de Trânsito/economia , Lesões Encefálicas Traumáticas/prevenção & controle , Traumatismos Craniocerebrais/prevenção & controle , Dispositivos de Proteção da Cabeça , Gastos em Saúde/estatística & dados numéricos , Motocicletas/legislação & jurisprudência , Acidentes de Trânsito/estatística & dados numéricos , Lesões Encefálicas Traumáticas/economia , Lesões Encefálicas Traumáticas/epidemiologia , Análise Custo-Benefício , Traumatismos Craniocerebrais/economia , Traumatismos Craniocerebrais/epidemiologia , Regulamentação Governamental , Dispositivos de Proteção da Cabeça/estatística & dados numéricos , Política de Saúde , Humanos , Renda , Pobreza , Estudos Retrospectivos , Vietnã/epidemiologia
19.
BMC Genomics ; 17(Suppl 10): 765, 2016 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-28185571

RESUMO

BACKGROUND: Given a new biological sequence, detecting membership in a known family is a basic step in many bioinformatics analyses, with applications to protein structure and function prediction and metagenomic taxon identification and abundance profiling, among others. Yet family identification of sequences that are distantly related to sequences in public databases or that are fragmentary remains one of the more difficult analytical problems in bioinformatics. RESULTS: We present a new technique for family identification called HIPPI (Hierarchical Profile Hidden Markov Models for Protein family Identification). HIPPI uses a novel technique to represent a multiple sequence alignment for a given protein family or superfamily by an ensemble of profile hidden Markov models computed using HMMER. An evaluation of HIPPI on the Pfam database shows that HIPPI has better overall precision and recall than blastp, HMMER, and pipelines based on HHsearch, and maintains good accuracy even for fragmentary query sequences and for protein families with low average pairwise sequence identity, both conditions where other methods degrade in accuracy. CONCLUSION: HIPPI provides accurate protein family identification and is robust to difficult model conditions. Our results, combined with observations from previous studies, show that ensembles of profile Hidden Markov models can better represent multiple sequence alignments than a single profile Hidden Markov model, and thus can improve downstream analyses for various bioinformatic tasks. Further research is needed to determine the best practices for building the ensemble of profile Hidden Markov models. HIPPI is available on GitHub at https://github.com/smirarab/sepp .


Assuntos
Algoritmos , Proteínas/classificação , Biologia Computacional , Bases de Dados de Proteínas , Internet , Cadeias de Markov , Proteínas/química , Proteínas/metabolismo , Alinhamento de Sequência , Interface Usuário-Computador
20.
NPJ Biofilms Microbiomes ; 2: 16004, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28721243

RESUMO

The standard pipeline for 16S amplicon analysis starts by clustering sequences within a percent sequence similarity threshold (typically 97%) into 'Operational Taxonomic Units' (OTUs). From each OTU, a single sequence is selected as a representative. This representative sequence is annotated, and that annotation is applied to all remaining sequences within that OTU. This perspective paper will discuss the known shortcomings of this standard approach using results obtained from the Human Microbiome Project. In particular, we will show that the traditional approach of using pairwise sequence alignments to compute sequence similarity can result in poorly clustered OTUs. As OTUs are typically annotated based upon a single representative sequence, poorly clustered OTUs can have significant impact on downstream analyses. These results suggest that we need to move beyond simple clustering techniques for 16S analysis.

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