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2.
Am J Hum Biol ; 35(11): e23943, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37358306

RESUMO

OBJECTIVES: Breastfeeding is an energetically costly and intense form of human parental investment, providing sole-source nutrition in early infancy and bioactive components, including immune factors. Given the energetic cost of lactation, milk factors may be subject to tradeoffs, and variation in concentrations have been explored utilizing the Trivers-Willard hypothesis. As human milk immune factors are critical to developing immune system and protect infants against pathogens, we tested whether concentrations of milk immune factors (IgA, IgM, IgG, EGF, TGFß2, and IL-10) vary in response to infant sex and maternal condition (proxied by maternal diet diversity [DD] and body mass index [BMI]) as posited in the Trivers-Willard hypothesis and consider the application of the hypothesis to milk composition. METHODS: We analyzed concentrations of immune factors in 358 milk samples collected from women residing in 10 international sites using linear mixed-effects models to test for an interaction between maternal condition, including population as a random effect and infant age and maternal age as fixed effects. RESULTS: IgG concentrations were significantly lower in milk produced by women consuming diets with low diversity with male infants than those with female infants. No other significant associations were identified. CONCLUSIONS: IgG concentrations were related to infant sex and maternal diet diversity, providing minimal support for the hypothesis. Given the lack of associations across other select immune factors, results suggest that the Trivers-Willard hypothesis may not be broadly applied to human milk immune factors as a measure of maternal investment, which are likely buffered against perturbations in maternal condition.


Assuntos
Leite Humano , Estado Nutricional , Feminino , Lactente , Masculino , Humanos , Lactação/fisiologia , Aleitamento Materno , Fatores Imunológicos , Imunoglobulina G
3.
J Proteome Res ; 21(4): 874-890, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35142523

RESUMO

The shell disorder models have predicted that SARS-CoV-2 is of a specific but peculiar evolutionary nature. All coronaviruses (CoVs) closely related to SARS-CoV-2 have been found to have the hardest outer shells (M protein) among CoVs. This hard shell (low M percentage of intrinsic disorder (PID)) is associated with burrowing animals, for example, pangolins, and is believed to be responsible for the high contagiousness of SARS-CoV-2 because it will be more resistant to antimicrobial enzymes found in saliva/mucus. Incoming clinical and experimental data do support this along with a prediction based on another aspect of the shell (N, inner shell) disorder models that SARS-CoV-1 is more virulent than SARS-CoV-2 because SARS-CoV-2 produces fewer virus copies in vital organs even if large amounts of infections particles are shed orally and nasally. A phylogenetic study using M reveals a closer relationship of SARS-CoV to pangolin-CoVs than the bat-RaTG13 found in Yunnan, China. Previous studies may have been confused by recombinations that were poorly handled. The shell disorder models suggest that a pangolin-CoV strain may have entered the human population in 2017 or before as an attenuated virus, which could explain why SARS-CoV is found to be highly adapted to humans.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , China , Filogenia , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética
4.
PLoS Genet ; 15(8): e1008315, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31425546

RESUMO

Cilia are evolutionarily conserved hair-like structures with a wide spectrum of key biological roles, and their dysfunction has been linked to a growing class of genetic disorders, known collectively as ciliopathies. Many strides have been made towards deciphering the molecular causes for these diseases, which have in turn expanded the understanding of cilia and their functional roles. One recently-identified ciliary gene is ARL2BP, encoding the ADP-Ribosylation Factor Like 2 Binding Protein. In this study, we have identified multiple ciliopathy phenotypes associated with mutations in ARL2BP in human patients and in a mouse knockout model. Our research demonstrates that spermiogenesis is impaired, resulting in abnormally shaped heads, shortened and mis-assembled sperm tails, as well as in loss of axonemal doublets. Additional phenotypes in the mouse included enlarged ventricles of the brain and situs inversus. Mouse embryonic fibroblasts derived from knockout animals revealed delayed depolymerization of primary cilia. Our results suggest that ARL2BP is required for the structural maintenance of cilia as well as of the sperm flagellum, and that its deficiency leads to syndromic ciliopathy.


Assuntos
Proteínas de Transporte/genética , Ciliopatias/genética , Infertilidade Masculina/genética , Proteínas de Membrana Transportadoras/genética , Fotofobia/genética , Adulto , Animais , Cílios/patologia , Ciliopatias/patologia , Modelos Animais de Doenças , Feminino , Humanos , Infertilidade Masculina/patologia , Masculino , Camundongos , Camundongos Knockout , Microtúbulos/metabolismo , Pessoa de Meia-Idade , Linhagem , Fotofobia/patologia , Motilidade dos Espermatozoides/genética , Cauda do Espermatozoide/patologia , Espermatogênese/genética , Síndrome , Fatores de Transcrição
5.
Genomics ; 113(4): 1867-1875, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33831438

RESUMO

Human milk oligosaccharides (HMO), the third most abundant component of human milk, are thought to be important contributors to infant health. Studies have provided evidence that geography, stage of lactation, and Lewis and secretor blood groups are associated with HMO profile. However, little is known about how variation across the genome may influence HMO composition among women in various populations. In this study, we performed genome-wide association analyses of 395 women from 8 countries to identify genetic regions associated with 19 different HMO. Our data support FUT2 as the most significantly associated (P < 4.23-9 to P < 4.5-70) gene with seven HMO and provide evidence of balancing selection for FUT2. Although polymorphisms in FUT3 were also associated with variation in lacto-N-fucopentaose II and difucosyllacto-N-tetrose, we found little evidence of selection on FUT3. To our knowledge, this is the first report of the use of genome-wide association analyses on HMO.


Assuntos
Estudo de Associação Genômica Ampla , Leite Humano , Oligossacarídeos , Feminino , Humanos , Lactação , Leite Humano/química , Oligossacarídeos/química
6.
J Proteome Res ; 19(11): 4355-4363, 2020 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-33006287

RESUMO

A model that predicts levels of coronavirus (CoV) respiratory and fecal-oral transmission potentials based on the shell disorder has been built using neural network (artificial intelligence, AI) analysis of the percentage of disorder (PID) in the nucleocapsid, N, and membrane, M, proteins of the inner and outer viral shells, respectively. Using primarily the PID of N, SARS-CoV-2 is grouped as having intermediate levels of both respiratory and fecal-oral transmission potentials. Related studies, using similar methodologies, have found strong positive correlations between virulence and inner shell disorder among numerous viruses, including Nipah, Ebola, and Dengue viruses. There is some evidence that this is also true for SARS-CoV-2 and SARS-CoV, which have N PIDs of 48% and 50%, and case-fatality rates of 0.5-5% and 10.9%, respectively. The underlying relationship between virulence and respiratory potentials has to do with the viral loads of vital organs and body fluids, respectively. Viruses can spread by respiratory means only if the viral loads in saliva and mucus exceed certain minima. Similarly, a patient is likelier to die when the viral load overwhelms vital organs. Greater disorder in inner shell proteins has been known to play important roles in the rapid replication of viruses by enhancing the efficiency pertaining to protein-protein/DNA/RNA/lipid bindings. This paper suggests a novel strategy in attenuating viruses involving comparison of disorder patterns of inner shells (N) of related viruses to identify residues and regions that could be ideal for mutation. The M protein of SARS-CoV-2 has one of the lowest M PID values (6%) in its family, and therefore, this virus has one of the hardest outer shells, which makes it resistant to antimicrobial enzymes in body fluid. While this is likely responsible for its greater contagiousness, the risks of creating an attenuated virus with a more disordered M are discussed.


Assuntos
Inteligência Artificial , Betacoronavirus , Infecções por Coronavirus , Pandemias , Pneumonia Viral , Vacinas Virais , Betacoronavirus/química , Betacoronavirus/genética , Betacoronavirus/metabolismo , Betacoronavirus/patogenicidade , COVID-19 , Vacinas contra COVID-19 , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Desenvolvimento de Medicamentos/métodos , Humanos , Proteínas Intrinsicamente Desordenadas/química , Proteínas Intrinsicamente Desordenadas/genética , Proteínas Intrinsicamente Desordenadas/metabolismo , Pandemias/prevenção & controle , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/prevenção & controle , Pneumonia Viral/transmissão , Pneumonia Viral/virologia , SARS-CoV-2 , Carga Viral , Proteínas Virais/química , Proteínas Virais/genética , Proteínas Virais/metabolismo
7.
J Proteome Res ; 19(11): 4543-4552, 2020 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-32790362

RESUMO

A model to predict the relative levels of respiratory and fecal-oral transmission potentials of coronaviruses (CoVs) by measuring the percentage of protein intrinsic disorder (PID) of the M (Membrane) and N (Nucleoprotein) proteins in their outer and inner shells, respectively, was built before the MERS-CoV outbreak. With MPID = 8.6% and NPID = 50.2%, the 2003 SARS-CoV falls into group B, which consists of CoVs with intermediate levels of both fecal-oral and respiratory transmission potentials. Further validation of the model came with MERS-CoV (MPID = 9%, NPID = 44%) and SARS-CoV-2 (MPID = 5.5%, NPID = 48%) falling into the groups C and B, respectively. Group C contains CoVs with higher fecal-oral but lower respiratory transmission potentials. Unlike SARS-CoV, SARS-CoV-2 with MPID = 5.5% has one of the hardest outer shells among CoVs. Because the hard shell is able to resist the antimicrobial enzymes in body fluids, the infected person is able to shed large quantities of viral particles via saliva and mucus, which could account for the higher contagiousness of SARS-COV-2. Further searches have found that high rigidity of the outer shell is characteristic for the CoVs of burrowing animals, such as rabbits (MPID = 5.6%) and pangolins (MPID = 5-6%), which are in contact with the buried feces. A closer inspection of pangolin-CoVs from 2017 to 2019 reveals that pangolins provided a unique window of opportunity for the entry of an attenuated SARS-CoV-2 precursor into the human population in 2017 or earlier, with the subsequent slow and silent spread as a mild cold that followed by its mutations into the current more virulent form. Evidence of this lies in both the genetic proximity of the pangolin-CoVs to SARS-CoV-2 (∼90%) and differences in N disorder. A 2017 pangolin-CoV strain shows evidence of higher levels of attenuation and higher fecal-oral transmission associated with lower human infectivity via having lower NPID (44.8%). Our shell disorder model predicts this to be a SARS-CoV-2 vaccine strain, as lower inner shell disorder is associated with the lesser virulence in a variety of viruses.


Assuntos
Betacoronavirus/química , Infecções por Coronavirus , Eutérios/virologia , Proteínas Intrinsicamente Desordenadas , Proteínas do Nucleocapsídeo , Pandemias , Pneumonia Viral , Animais , COVID-19 , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/veterinária , Infecções por Coronavirus/virologia , Proteínas do Nucleocapsídeo de Coronavírus , Humanos , Pandemias/veterinária , Fosfoproteínas , Pneumonia Viral/transmissão , Pneumonia Viral/veterinária , Pneumonia Viral/virologia , Coelhos/virologia , SARS-CoV-2 , Proteínas Virais
8.
Microb Pathog ; 144: 104177, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32244041

RESUMO

The coronavirus (CoV) family consists of viruses that infects a variety of animals including humans with various levels of respiratory and fecal-oral transmission levels depending on the behavior of the viruses' natural hosts and optimal viral fitness. A model to classify and predict the levels of respective respiratory and fecal-oral transmission potentials of the various viruses was built before the outbreak of MERS-CoV using AI and empirically-based molecular tools to predict the disorder level of proteins. Using the percentages of intrinsic disorder (PID) of the nucleocapsid (N) and membrane (M) proteins of CoV, the model easily clustered the viruses into three groups with the SARS-CoV (M PID = 8%, N PID = 50%) falling into Category B, in which viruses have intermediate levels of both respiratory and fecal-oral transmission potentials. Later, MERS-CoV (M PID = 9%, N PID = 44%) was found to be in Category C, which consists of viruses with lower respiratory transmission potential but with higher fecal-oral transmission capabilities. Based on the peculiarities of disorder distribution, the SARS-CoV-2 (M PID = 6%, N PID = 48%) has to be placed in Category B. Our data show however, that the SARS-CoV-2 is very strange with one of the hardest protective outer shell, (M PID = 6%) among coronaviruses. This means that it might be expected to be highly resilient in saliva or other body fluids and outside the body. An infected body is likelier to shed greater numbers of viral particles since the latter is more resistant to antimicrobial enzymes in body fluids. These particles are also likelier to remain active longer. These factors could account for the greater contagiousness of the SARS-CoV-2 and have implications for efforts to prevent its spread.


Assuntos
Líquidos Corporais/virologia , Infecções por Coronavirus/transmissão , Fezes/virologia , Pneumonia Viral/transmissão , Síndrome Respiratória Aguda Grave/transmissão , Betacoronavirus/metabolismo , COVID-19 , Humanos , Coronavírus da Síndrome Respiratória do Oriente Médio/metabolismo , Pandemias , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/metabolismo , SARS-CoV-2 , Saliva/virologia
9.
Microb Pathog ; 141: 103976, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31940461

RESUMO

The Nipah Virus (NiV) was first isolated during a 1998-9 outbreak in Malaysia. The outbreak initially infected farm pigs and then moved to humans from pigs with a case-fatality rate (CFR) of about 40%. After 2001, regular outbreaks occurred with higher CFRs (~71%, 2001-5, ~93%, 2008-12). The spread arose from drinking virus-laden palm date sap and human-to-human transmission. Intrinsic disorder analysis revealed strong correlation between the percentage of disorder in the N protein and CFR (Regression: r2 = 0.93, p < 0.01, ANOVA: p < 0.01). Distinct disorder and, therefore, genetic differences can be found in all three group of strains. The fact that the transmission modes of the Malaysia strain are different from those of the Bangladesh strains suggests that the correlations may also be linked to the modes of viral transmission. Analysis of the NiV and related viruses suggests links between modes of transmission and disorder of not just the N protein but, also, of M shell protein. The links among shell disorder, transmission modes, and virulence suggest mechanisms by which viruses are attenuated as they passed through different cell hosts from different animal species. These have implications for development of vaccines and epidemiological molecular analytical tools to contain outbreaks.


Assuntos
Infecções por Henipavirus/virologia , Vírus Nipah/patogenicidade , Sequência de Aminoácidos , Animais , Surtos de Doenças , Suscetibilidade a Doenças , Evolução Molecular , Genoma Viral , Infecções por Henipavirus/epidemiologia , Humanos , Modelos Biológicos , Mortalidade , Vírus Nipah/classificação , Vírus Nipah/genética , Filogenia , Conformação Proteica , Análise de Sequência de DNA , Suínos , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/virologia , Proteínas Virais/química , Proteínas Virais/genética , Virulência
10.
Am J Phys Anthropol ; 169(3): 526-539, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31012086

RESUMO

OBJECTIVES: Establishment and development of the infant gastrointestinal microbiome (GIM) varies cross-culturally and is thought to be influenced by factors such as gestational age, birth mode, diet, and antibiotic exposure. However, there is little data as to how the composition of infants' households may play a role, particularly from a cross-cultural perspective. Here, we examined relationships between infant fecal microbiome (IFM) diversity/composition and infants' household size, number of siblings, and number of other household members. MATERIALS AND METHODS: We analyzed 377 fecal samples from healthy, breastfeeding infants across 11 sites in eight different countries (Ethiopia, The Gambia, Ghana, Kenya, Peru, Spain, Sweden, and the United States). Fecal microbial community structure was determined by amplifying, sequencing, and classifying (to the genus level) the V1-V3 region of the bacterial 16S rRNA gene. Surveys administered to infants' mothers identified household members and composition. RESULTS: Our results indicated that household composition (represented by the number of cohabitating siblings and other household members) did not have a measurable impact on the bacterial diversity, evenness, or richness of the IFM. However, we observed that variation in household composition categories did correspond to differential relative abundances of specific taxa, namely: Lactobacillus, Clostridium, Enterobacter, and Klebsiella. DISCUSSION: This study, to our knowledge, is the largest cross-cultural study to date examining the association between household composition and the IFM. Our results indicate that the social environment of infants (represented here by the proxy of household composition) may influence the bacterial composition of the infant GIM, although the mechanism is unknown. A higher number and diversity of cohabitants and potential caregivers may facilitate social transmission of beneficial bacteria to the infant gastrointestinal tract, by way of shared environment or through direct physical and social contact between the maternal-infant dyad and other household members. These findings contribute to the discussion concerning ways by which infants are influenced by their social environments and add further dimensionality to the ongoing exploration of social transmission of gut microbiota and the "old friends" hypothesis.


Assuntos
Bactérias , Características da Família/etnologia , Microbioma Gastrointestinal/genética , Adolescente , Adulto , África , América , Antropologia Física , Bactérias/classificação , Bactérias/genética , Aleitamento Materno , Comparação Transcultural , Europa (Continente) , Fezes/microbiologia , Humanos , Lactente , Recém-Nascido , Mães , Irmãos , Adulto Jovem
11.
Biol Reprod ; 96(5): 993-1006, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-28430876

RESUMO

Intraflagellar transport (IFT) is a conserved mechanism essential for the assembly and maintenance of most eukaryotic cilia and flagella. However, IFT25, a component of the IFT complex, is not required for the formation of cilia in somatic tissues. In mice, the gene is highly expressed in the testis, and its expression is upregulated during the final phase when sperm flagella are formed. To investigate the role of IFT25 in sperm flagella formation, the gene was specifically disrupted in male germ cells. All homozygous knockout mice survived to adulthood and did not show any gross abnormalities. However, all homozygous knockout males were completely infertile. Sperm numbers were reduced and these sperm were completely immotile. Multiple morphological abnormalities were observed in sperm, including round heads, short and bent tails, with some tails showing branched flagella and others with frequent abnormal thicknesses, as well as swollen tips of the tail. Transmission electron microscopy revealed that flagellar accessory structures, including the fibrous sheath and outer dense fibers, were disorganized, and most sperm had also lost the "9+2" microtubule structure. In the testis, IFT25 forms a complex with other IFT proteins. In Ift25 knockout testes, IFT27, an IFT25 binding partner, was missing, and IFT20 and IFT81 levels were also reduced. Our findings suggest that IFT25, although not necessary for the formation of cilia in somatic cells, is indispensable for sperm flagellum formation and male fertility in mice.


Assuntos
Cílios/fisiologia , Flagelos/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Espermatozoides/fisiologia , Animais , Fertilidade/genética , Flagelos/ultraestrutura , Infertilidade Masculina/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Camundongos , Camundongos Knockout , Microtúbulos/ultraestrutura , Contagem de Espermatozoides , Motilidade dos Espermatozoides/genética , Espermatozoides/ultraestrutura , Testículo/metabolismo , Proteínas rab de Ligação ao GTP/genética , Proteínas rab de Ligação ao GTP/fisiologia
12.
Bioinformatics ; 31(11): 1830-2, 2015 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-25630378

RESUMO

MOTIVATION: We present a novel method and corresponding application, MetAmp, to combine amplicon data from multiple genomic markers into Operational Taxonomic Units (OTUs) for microbial community analysis, calibrating the markers using data from known microbial genomes. When amplicons for multiple markers such as the 16S rRNA gene hypervariable regions are available, MetAmp improves the accuracy of OTU-based methods for characterizing bacterial composition and community structure. MetAmp works best with at least three markers, and is applicable to non-bacterial analyses and to non 16S markers. Our application and testing have been limited to 16S analysis of microbial communities. RESULTS: We clustered standard test sequences derived from the Human Microbiome Mock Community test sets and compared MetAmp and other tools with respect to their ability to recover OTUs for these benchmark bacterial communities. MetAmp compared favorably to QIIME, UPARSE and Mothur using amplicons from one, two, and three markers. AVAILABILITY AND IMPLEMENTATION: MetAmp is available at http://izhbannikov.github.io/MetAmp/.


Assuntos
Metagenômica/métodos , Software , Algoritmos , Classificação/métodos , Marcadores Genéticos , Humanos , Microbiota , RNA Ribossômico 16S/genética
13.
Bioinformatics ; 31(4): 602-3, 2015 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-25332377

RESUMO

SUMMARY: In this article we present Simple Exploration of Ecological Data (Seed), a data exploration tool for microbial communities. Seed is written in R using the Shiny library. This provides access to powerful R-based functions and libraries through a simple user interface. Seed allows users to explore ecological datasets using principal coordinate analyses, scatter plots, bar plots, hierarchal clustering and heatmaps. AVAILABILITY AND IMPLEMENTATION: Seed is open source and available at https://github.com/danlbek/Seed. CONTACT: danlbek@gmail.com SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Bactérias/classificação , Bactérias/genética , Biologia Computacional/métodos , Gráficos por Computador , Ecologia , Software
14.
Adv Anat Embryol Cell Biol ; 220: 15-33, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27194348

RESUMO

The acrosome, a single exocytotic vesicle on the head of sperm, has an essential role in fertilization, but the exact mechanisms by which it facilitates sperm-egg interactions remain unresolved. The acrosome contains dozens of secretory proteins that are packaged into the forming structure during spermatogenesis; many of these proteins are localized into specific topographical areas of the acrosome, while others are more diffusely distributed. Acrosomal proteins can also be biochemically classified as components of the acrosomal matrix, a large, relatively insoluble complex, or as soluble proteins. This review focuses on recent findings using genetically modified mice (gene knockouts and transgenic "green acrosome" mice) to study the effects of eliminating acrosomal matrix-associated proteins on sperm structure and function. Some gene knockouts produce infertile phenotypes with obviously missing, specific activities that affect acrosome biogenesis during spermatogenesis or interfere with acrosome function in mature sperm. Mutations that delete some components produce fertile phenotypes with subtler effects that provide useful insights into acrosomal matrix function in fertilization. In general, these studies enable the reassessment of paradigms to explain acrosome formation and function and provide novel, objective insights into the roles of acrosomal matrix proteins in fertilization. The use of genetically engineered mouse models has yielded new mechanistic information that complements recent, important in vivo imaging studies.


Assuntos
Acrossomo/metabolismo , Fertilização/fisiologia , Infertilidade Masculina/genética , Proteínas de Membrana/genética , Peptídeo Hidrolases/genética , Acrossomo/química , Animais , Feminino , Regulação da Expressão Gênica , Técnicas de Inativação de Genes , Masculino , Fusão de Membrana , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Transgênicos , Mutação , Óvulo/citologia , Óvulo/fisiologia , Peptídeo Hidrolases/metabolismo , Maturação do Esperma/fisiologia
15.
Brief Bioinform ; 13(4): 420-9, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22308073

RESUMO

This article reviews recent advances in 'microbiome studies': molecular, statistical and graphical techniques to explore and quantify how microbial organisms affect our environments and ourselves given recent increases in sequencing technology. Microbiome studies are moving beyond mere inventories of specific ecosystems to quantifications of community diversity and descriptions of their ecological function. We review the last 24 months of progress in this sort of research, and anticipate where the next 2 years will take us. We hope that bioinformaticians will find this a helpful springboard for new collaborations with microbiologists.


Assuntos
DNA/química , Genômica/métodos , Metagenoma , Ecossistema
16.
Bioinformatics ; 28(7): 1045-7, 2012 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-22333246

RESUMO

MOTIVATION: The massive data produced by next-generation sequencing require advanced statistical tools. We address estimating the total diversity or species richness in a population. To date, only relatively simple methods have been implemented in available software. There is a need for software employing modern, computationally intensive statistical analyses including error, goodness-of-fit and robustness assessments. RESULTS: We present CatchAll, a fast, easy-to-use, platform-independent program that computes maximum likelihood estimates for finite-mixture models, weighted linear regression-based analyses and coverage-based non-parametric methods, along with outlier diagnostics. Given sample 'frequency count' data, CatchAll computes 12 different diversity estimates and applies a model-selection algorithm. CatchAll also derives discounted diversity estimates to adjust for possibly uncertain low-frequency counts. It is accompanied by an Excel-based graphics program. AVAILABILITY: Free executable downloads for Linux, Windows and Mac OS, with manual and source code, at www.northeastern.edu/catchall. CONTACT: jab18@cornell.edu.


Assuntos
Genética Populacional/métodos , Genética Populacional/estatística & dados numéricos , Modelos Estatísticos , Software , Algoritmos , Bacteriófagos/genética , Biologia Computacional/métodos , Funções Verossimilhança , Modelos Lineares
17.
Bioinformatics ; 28(16): 2198-9, 2012 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-22692220

RESUMO

UNLABELLED: Microbial communities have an important role in natural ecosystems and have an impact on animal and human health. Intuitive graphic and analytical tools that can facilitate the study of these communities are in short supply. This article introduces Microbial Community Analysis GUI, a graphical user interface (GUI) for the R-programming language (R Development Core Team, 2010). With this application, researchers can input aligned and clustered sequence data to create custom abundance tables and perform analyses specific to their needs. This GUI provides a flexible modular platform, expandable to include other statistical tools for microbial community analysis in the future. AVAILABILITY: The mcaGUI package and source are freely available as part of Bionconductor at http://www.bioconductor.org/packages/release/bioc/html/mcaGUI.html


Assuntos
Gráficos por Computador , Metagenoma , Software , Interface Usuário-Computador , Biodiversidade , Análise por Conglomerados , Análise Multivariada , Análise de Componente Principal , Análise de Sequência/métodos
18.
Bioinformatics ; 27(12): 1700-1, 2011 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-21498398

RESUMO

SUMMARY: OTUbase is an R package designed to facilitate the analysis of operational taxonomic unit (OTU) data and sequence classification (taxonomic) data. Currently there are programs that will cluster sequence data into OTUs and/or classify sequence data into known taxonomies. However, there is a need for software that can take the summarized output of these programs and organize it into easily accessed and manipulated formats. OTUbase provides this structure and organization within R, to allow researchers to easily manipulate the data with the rich library of R packages currently available for additional analysis. AVAILABILITY: OTUbase is an R package available through Bioconductor. It can be found at http://www.bioconductor.org/packages/release/bioc/html/OTUbase.html.


Assuntos
Análise de Sequência de DNA , Software , Classificação/métodos , Análise por Conglomerados
19.
Biomolecules ; 12(5)2022 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-35625559

RESUMO

Before the SARS-CoV-2 Omicron variant emergence, shell disorder models (SDM) suggested that an attenuated precursor from pangolins may have entered humans in 2017 or earlier. This was based on a shell disorder analysis of SARS-CoV-1/2 and pangolin-Cov-2017. The SDM suggests that Omicron is attenuated with almost identical N (inner shell) disorder as pangolin-CoV-2017 (N-PID (percentage of intrinsic disorder): 44.8% vs. 44.9%-lower than other variants). The outer shell disorder (M-PID) of Omicron is lower than that of other variants and pangolin-CoV-2017 (5.4% vs. 5.9%). COVID-19-related CoVs have the lowest M-PIDs (hardest outer shell) among all CoVs. This is likely to be responsible for the higher contagiousness of SARS-CoV-2 and Omicron, since hard outer shell protects the virion from salivary/mucosal antimicrobial enzymes. Phylogenetic study using M reveals that Omicron branched off from an ancestor of the Wuhan-Hu-1 strain closely related to pangolin-CoVs. M, being evolutionarily conserved in COVID-19, is most ideal for COVID-19 phylogenetic study. Omicron may have been hiding among burrowing animals (e.g., pangolins) that provide optimal evolutionary environments for attenuation and increase shell hardness, which is essential for fecal-oral-respiratory transmission via buried feces. Incoming data support SDM e.g., the presence of fewer infectious particles in the lungs than in the bronchi upon infection.


Assuntos
COVID-19 , Quirópteros , Animais , Filogenia , SARS-CoV-2
20.
AI Ethics ; 2(4): 635-643, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34870283

RESUMO

Today Artificial Intelligence (AI) supports difficult decisions about policy, health, and our personal lives. The AI algorithms we develop and deploy to make sense of information, are informed by data, and based on models that capture and use pertinent details of the population or phenomenon being analyzed. For any application area, more importantly in precision medicine which directly impacts human lives, the data upon which algorithms are run must be procured, cleaned, and organized well to assure reliable and interpretable results, and to assure that they do not perpetrate or amplify human prejudices. This must be done without violating basic assumptions of the algorithms in use. Algorithmic results need to be clearly communicated to stakeholders and domain experts to enable sound conclusions. Our position is that AI holds great promise for supporting precision medicine, but we need to move forward with great care, with consideration for possible ethical implications. We make the case that a no-boundary or convergent approach is essential to support sound and ethical decisions. No-boundary thinking supports problem definition and solving with teams of experts possessing diverse perspectives. When dealing with AI and the data needed to use AI, there is a spectrum of activities that needs the attention of a no-boundary team. This is necessary if we are to draw viable conclusions and develop actions and policies based on the AI, the data, and the scientific foundations of the domain in question.

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