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1.
Life Sci Alliance ; 6(7)2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37041017

RESUMO

A soluble ACE2 protein bioengineered for long duration of action and high affinity to SARS-CoV-2 was administered either intranasally (IN) or intraperitoneally (IP) to SARS-CoV-2-inoculated k18hACE2 mice. This decoy protein (ACE2 618-DDC-ABD) was given either IN or IP, pre- and post-inoculation, or IN, IP, or IN + IP but only post-inoculation. Survival by day 5 was 0% in untreated mice, 40% in the IP-pre, and 90% in the IN-pre group. In the IN-pre group, brain histopathology was essentially normal and lung histopathology significantly improved. Consistent with this, brain SARS-CoV-2 titers were undetectable and lung titers reduced in the IN-pre group. When ACE2 618-DDC-ABD was administered only post-inoculation, survival was 30% in the IN + IP, 20% in the IN, and 20% in the IP group. We conclude that ACE2 618-DDC-ABD results in markedly improved survival and provides organ protection when given intranasally as compared with when given either systemically or after viral inoculation, and that lowering brain titers is a critical determinant of survival and organ protection.


Assuntos
Enzima de Conversão de Angiotensina 2 , COVID-19 , Animais , Camundongos , SARS-CoV-2 , Encéfalo
4.
Proc Natl Acad Sci U S A ; 117(17): 9241-9243, 2020 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-32269081

RESUMO

In a phylogenetic network analysis of 160 complete human severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2) genomes, we find three central variants distinguished by amino acid changes, which we have named A, B, and C, with A being the ancestral type according to the bat outgroup coronavirus. The A and C types are found in significant proportions outside East Asia, that is, in Europeans and Americans. In contrast, the B type is the most common type in East Asia, and its ancestral genome appears not to have spread outside East Asia without first mutating into derived B types, pointing to founder effects or immunological or environmental resistance against this type outside Asia. The network faithfully traces routes of infections for documented coronavirus disease 2019 (COVID-19) cases, indicating that phylogenetic networks can likewise be successfully used to help trace undocumented COVID-19 infection sources, which can then be quarantined to prevent recurrent spread of the disease worldwide.


Assuntos
Betacoronavirus/genética , Infecções por Coronavirus/virologia , Pneumonia Viral/virologia , Animais , COVID-19 , Quirópteros/virologia , Genoma Viral , Humanos , Pandemias , Filogenia , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/genética , SARS-CoV-2
5.
Cancers (Basel) ; 12(2)2020 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-32046290

RESUMO

Personalized treatment vs. standard of care is much debated, especially in clinical practice. Here we investigated whether overall survival differences in metastatic colorectal cancer patients are explained by tumor mutation profiles or by treatment differences in real clinical practice. Our retrospective study of metastatic colorectal cancer patients of confirmed European ancestry comprised 54 Americans and 54 gender-matched Germans. The Americans received standard of care, and on treatment failure, 35 patients received individualized treatments. The German patients received standard of care only. Tumor mutations, tumor mutation burden and microsatellite status were identified by using the FoundationOne assay or the IDT Pan-Cancer assay. High-risk patients were identified according to the mutational classification by Schell and colleagues. Results: Kaplan-Meier estimates show the high-risk patients to survive 16 months longer under individualized treatments than those under only standard of care, in the median (p < 0.001). Tumor mutation profiles stratify patients by risk groups but not by country. Conclusions: High-risk patients appear to survive significantly longer (p < 0.001) if they receive individualized treatments after the exhaustion of standard of care treatments. Secondly, the tumor mutation landscape in Americans and Germans is congruent and thus warrants the transatlantic exchange of successful treatment protocols and the harmonization of guidelines.

6.
Artigo em Inglês | MEDLINE | ID: mdl-30709874

RESUMO

Whole-genome and whole-exome sequencing of individual patients allow the study of rare and potentially causative genetic variation. In this study, we sequenced DNA of a trio comprising a boy with very-early-onset inflammatory bowel disease (veoIBD) and his unaffected parents. We identified a rare, X-linked missense variant in the NAPDH oxidase NOX1 gene (c.C721T, p.R241C) in heterozygous state in the mother and in hemizygous state in the patient. We discovered that, in addition, the patient was homozygous for a common missense variant in the CYBA gene (c.T214C, p.Y72H). CYBA encodes the p22phox protein, a cofactor for NOX1. Functional assays revealed reduced cellular ROS generation and antibacterial capacity of NOX1 and p22phox variants in intestinal epithelial cells. Moreover, the identified NADPH oxidase complex variants affected NOD2-mediated immune responses, and p22phox was identified as a novel NOD2 interactor. In conclusion, we detected missense variants in a veoIBD patient that disrupt the host response to bacterial challenges and reduce protective innate immune signaling via NOD2. We assume that the patient's individual genetic makeup favored disturbed intestinal mucosal barrier function.


Assuntos
Doenças Inflamatórias Intestinais/genética , Mutação de Sentido Incorreto , NADPH Oxidase 1/genética , NADPH Oxidases/genética , Linhagem Celular Tumoral , Cromossomos Humanos X , Homozigoto , Humanos , Doenças Inflamatórias Intestinais/enzimologia , Masculino , Proteína Adaptadora de Sinalização NOD2/genética , Polimorfismo de Nucleotídeo Único , Sequenciamento do Exoma , Sequenciamento Completo do Genoma
8.
Proc Biol Sci ; 282(1803): 20142898, 2015 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-25694621

RESUMO

Men age and die, while cells in their germline are programmed to be immortal. To elucidate how germ cells maintain viable DNA despite increasing parental age, we analysed DNA from 24 097 parents and their children, from Europe, the Middle East and Africa. We chose repetitive microsatellite DNA that mutates (unlike point mutations) only as a result of cellular replication, providing us with a natural 'cell-cycle counter'. We observe, as expected, that the overall mutation rate for fathers is seven times higher than for mothers. Also as expected, mothers have a low and lifelong constant DNA mutation rate. Surprisingly, however, we discover that (i) teenage fathers already set out from a much higher mutation rate than teenage mothers (potentially equivalent to 77-196 male germline cell divisions by puberty); and (ii) ageing men maintain sperm DNA quality similar to that of teenagers, presumably by using fresh batches of stem cells known as 'A-dark spermatogonia'.


Assuntos
Mutação em Linhagem Germinativa , Repetições de Microssatélites , Adolescente , Adulto , África , Fatores Etários , Idoso , Criança , Europa (Continente) , Pai , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Oriente Médio , Mães , Fatores Sexuais , Espermatogônias/citologia , Espermatozoides/citologia
9.
Nat Commun ; 5: 5631, 2014 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-25463651

RESUMO

In 2012, a skeleton was excavated at the presumed site of the Grey Friars friary in Leicester, the last-known resting place of King Richard III. Archaeological, osteological and radiocarbon dating data were consistent with these being his remains. Here we report DNA analyses of both the skeletal remains and living relatives of Richard III. We find a perfect mitochondrial DNA match between the sequence obtained from the remains and one living relative, and a single-base substitution when compared with a second relative. Y-chromosome haplotypes from male-line relatives and the remains do not match, which could be attributed to a false-paternity event occurring in any of the intervening generations. DNA-predicted hair and eye colour are consistent with Richard's appearance in an early portrait. We calculate likelihood ratios for the non-genetic and genetic data separately, and combined, and conclude that the evidence for the remains being those of Richard III is overwhelming.


Assuntos
Cromossomos Humanos Y/genética , Impressões Digitais de DNA , DNA Mitocondrial/análise , Genética Forense , Sequência de Bases , Antropologia Forense , Haplótipos , Humanos , Masculino , Dados de Sequência Molecular , Paternidade
10.
Front Pharmacol ; 5: 232, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25374542

RESUMO

Multiple software programs are available for designing and running large scale system-level pharmacology models used in the drug development process. Depending on the problem, scientists may be forced to use several modeling tools that could increase model development time, IT costs and so on. Therefore, it is desirable to have a single platform that allows setting up and running large-scale simulations for the models that have been developed with different modeling tools. We developed a workflow and a software platform in which a model file is compiled into a self-contained executable that is no longer dependent on the software that was used to create the model. At the same time the full model specifics is preserved by presenting all model parameters as input parameters for the executable. This platform was implemented as a model agnostic, therapeutic area agnostic and web-based application with a database back-end that can be used to configure, manage and execute large-scale simulations for multiple models by multiple users. The user interface is designed to be easily configurable to reflect the specifics of the model and the user's particular needs and the back-end database has been implemented to store and manage all aspects of the systems, such as Models, Virtual Patients, User Interface Settings, and Results. The platform can be adapted and deployed on an existing cluster or cloud computing environment. Its use was demonstrated with a metabolic disease systems pharmacology model that simulates the effects of two antidiabetic drugs, metformin and fasiglifam, in type 2 diabetes mellitus patients.

11.
Nucleic Acids Res ; 41(1): e16, 2013 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-22965131

RESUMO

Scientists working with single-nucleotide variants (SNVs), inferred by next-generation sequencing software, often need further information regarding true variants, artifacts and sequence coverage gaps. In clinical diagnostics, e.g. SNVs must usually be validated by visual inspection or several independent SNV-callers. We here demonstrate that 0.5-60% of relevant SNVs might not be detected due to coverage gaps, or might be misidentified. Even low error rates can overwhelm the true biological signal, especially in clinical diagnostics, in research comparing healthy with affected cells, in archaeogenetic dating or in forensics. For these reasons, we have developed a package called pibase, which is applicable to diploid and haploid genome, exome or targeted enrichment data. pibase extracts details on nucleotides from alignment files at user-specified coordinates and identifies reproducible genotypes, if present. In test cases pibase identifies genotypes at 99.98% specificity, 10-fold better than other tools. pibase also provides pair-wise comparisons between healthy and affected cells using nucleotide signals (10-fold more accurately than a genotype-based approach, as we show in our case study of monozygotic twins). This comparison tool also solves the problem of detecting allelic imbalance within heterozygous SNVs in copy number variation loci, or in heterogeneous tumor sequences.


Assuntos
Variação Genética , Sequenciamento de Nucleotídeos em Larga Escala , Alinhamento de Sequência , Análise de Sequência de DNA , Software , Genômica , Humanos , Filogenia , Reprodutibilidade dos Testes , Gêmeos Monozigóticos/genética
14.
Science ; 334(6052): 94-8, 2011 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-21940856

RESUMO

We present an Aboriginal Australian genomic sequence obtained from a 100-year-old lock of hair donated by an Aboriginal man from southern Western Australia in the early 20th century. We detect no evidence of European admixture and estimate contamination levels to be below 0.5%. We show that Aboriginal Australians are descendants of an early human dispersal into eastern Asia, possibly 62,000 to 75,000 years ago. This dispersal is separate from the one that gave rise to modern Asians 25,000 to 38,000 years ago. We also find evidence of gene flow between populations of the two dispersal waves prior to the divergence of Native Americans from modern Asian ancestors. Our findings support the hypothesis that present-day Aboriginal Australians descend from the earliest humans to occupy Australia, likely representing one of the oldest continuous populations outside Africa.


Assuntos
Genoma Humano , Havaiano Nativo ou Outro Ilhéu do Pacífico/genética , Animais , Ásia , Povo Asiático/genética , População Negra , Simulação por Computador , DNA Mitocondrial/genética , Emigração e Imigração , Etnicidade/genética , Ásia Oriental , Fluxo Gênico , Frequência do Gene , Genética Populacional/métodos , Genoma Mitocondrial , Haplótipos , Hominidae/genética , Humanos , Desequilíbrio de Ligação , Masculino , Filogenia , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA , Austrália Ocidental , População Branca/genética
15.
J Cell Biochem ; 112(12): 3573-81, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21780162

RESUMO

Phosphatidylinositol-3-kinases (PI3Ks) exert a variety of signaling functions in eukaryotes. We suppressed the PI3K regulatory subunit p85α using a small interfering RNA (Pik3r1 siRNA) and examined the effects on embryoid body (EB) development in hanging drop culture. We observed a 150% increase in the volume of the treated EBs within 24 h, compared to the negative controls. Fluorescence Activated Cell Sorting (FACS) assays showed that this increase in volume is not due to increased cellular proliferation. Instead, the increase in volume appears to be due to reduced cellular aggregation and adherence. This is further shown by our observation that 40% of treated EBs form twin instead of single EBs, and that they have a significantly reduced ability to adhere to culture dishes when plated. A time course over the first 96 h reveals that the impaired adherence is transient and explained by an initial 12-hour delay in EB development. Quantitative PCR expression analysis suggests that the adhesion molecule integrin-ß1 (ITGB1) is transiently downregulated by the p85α suppression. In conclusion we found that suppressing p85α leads to a delay in forming compact EBs, accompanied by a transient inability of the EBs to undergo normal cell-cell and cell-substrate adhesion.


Assuntos
Adesão Celular , Corpos Embrioides/citologia , Inibidores de Fosfoinositídeo-3 Quinase , Western Blotting , Diferenciação Celular , Técnicas de Silenciamento de Genes , Fosfatidilinositol 3-Quinases/química , Fosfatidilinositol 3-Quinases/genética , Reação em Cadeia da Polimerase , RNA Interferente Pequeno
16.
Int J Legal Med ; 124(6): 617-22, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20830591

RESUMO

Horse mtDNA profiling can be useful in forensic work investigating degraded samples, hair shafts or highly dilute samples. Degraded DNA often does not allow sequencing of fragments longer than 200 nucleotides. In this study we therefore search for the most discriminatory sections within the hypervariable horse mtDNA control region. Among a random sample of 39 horses, 32 different sequences were identified in a stretch of 921 nucleotides. The sequences were assigned to the published mtDNA types A-G, and to a newly labelled minor type H. The random match probability within the analysed samples is 3.61%, and the average pairwise sequence difference is 15 nucleotides. In a "sliding window" analysis of 200-nucleotide sections of the mtDNA control region, we find that the known repetitive central motif divides the mtDNA control region into a highly diverse segment and a markedly less discriminatory segment.


Assuntos
Impressões Digitais de DNA/métodos , DNA Mitocondrial/análise , Genética Forense/métodos , Cabelo/química , Cavalos/classificação , Cavalos/genética , Animais , Cruzamento , Região de Controle de Locus Gênico , Sequências Repetitivas de Ácido Nucleico , Especificidade da Espécie
17.
Int J Legal Med ; 124(2): 133-42, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19937256

RESUMO

We present allelic data for three known and one new C-tract in the human mitochondrial DNA (mtDNA) control region, and we measure intergenerational mutation rates at such C-tracts. In detail, in a sample of 1,172 mtDNA sequences, we demonstrate the existence of an instability threshold of eight consecutive cytosines, at and above which the phenomenon of length heteroplasmy arises. To determine mutation rates, we draw on mtDNA sequences in up to four generations of 248 pedigrees for families living in high or low-radiation environmental conditions. The high-radiation sample gives the most conservative (fastest) mutation rate likely to be encountered in any forensic context. We find that the C-tract mutation rate is up to 6% per generation, and we observe an excess of cytosine gains over losses. Case studies and guidelines for evaluating mtDNA heteroplasmy are provided.


Assuntos
DNA Mitocondrial/genética , Região de Controle de Locus Gênico/genética , Polimorfismo Genético , Alelos , Radiação de Fundo , Criança , Feminino , Humanos , Mutação , Linhagem , Análise de Sequência de DNA
18.
Psychother Psychosom Med Psychol ; 60(2): 73-7, 2010 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-19753512

RESUMO

The influence of day nursery in early childhood on later mental and social development has been controversially discussed for a long time. Opponents of day nurseries express the considerable concern that serious negative mental consequences in later life result from early separation from the mother. A sample of n=383 respondents (54.2% women, aged 34.2 years on average) from the twenty-first wave of the Saxony Longitudinal Study (2007) was analyzed regarding the impact of day nursery in early childhood on different psychological indicators measured later. By applying standardized instruments several aspects were examined such as anxiety, depression, the occurrence of common somatic symptoms, attachment, confidence towards the future, experiences of menace, and common values towards political aspects. The findings show various gender differences, e. g. women report a worse mental health. Yet, only one of the examined indicators can be explained by day nursery in early childhood: respondents who had not been in day nursery felt more threatened by potential stressful life-events, e. g. unemployment. Furthermore the analysis of variance indicates some interaction effects between gender and day nursery in early childhood. Data doesn't support the critic that day nursery in early childhood negatively influences mental health at a later age. A particular positive impact of day nursery in early childhood on the examined aspects cannot be assumed, either. Facing the ongoing political debate on the expansion of day nursery facilities, further research is needed focusing more in detail on qualitative aspects of day nursery.


Assuntos
Creches , Desenvolvimento Infantil , Saúde Mental , Adulto , Pré-Escolar , Feminino , Humanos , Estudos Longitudinais , Masculino , Privação Materna , Transtornos Mentais/epidemiologia , Caracteres Sexuais , Estresse Psicológico
19.
Proc Biol Sci ; 275(1642): 1501-8, 2008 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-18364314

RESUMO

North Greenland Polar Eskimos are the only hunter-gatherer population, to our knowledge, who can offer precise genealogical records spanning several generations. This is the first report from Eskimos on two key parameters in population genetics, namely, generation time (T) and effective population size (Ne). The average mother-daughter and father-son intervals were 27 and 32 years, respectively, roughly similar to the previously published generation times obtained from recent agricultural societies across the world. To gain an insight for the generation time in our distant ancestors, we calculated maternal generation time for two wild chimpanzee populations. We also provide the first comparison among three distinct approaches (genealogy, variance and life table methods) for calculating Ne, which resulted in slightly differing values for the Eskimos. The ratio of the effective to the census population size is estimated as 0.6-0.7 for autosomal and X-chromosomal DNA, 0.7-0.9 for mitochondrial DNA and 0.5 for Y-chromosomal DNA. A simulation of alleles along the genealogy suggested that Y-chromosomal DNA may drift a little faster than mitochondrial DNA in this population, in contrast to agricultural Icelanders. Our values will be useful not only in prehistoric population inference but also in understanding the shaping of our genome today.


Assuntos
Características da Família/etnologia , Genética Populacional , Inuíte/genética , Pan troglodytes/genética , Animais , Deriva Genética , Groenlândia , Humanos , Densidade Demográfica
20.
Mol Biol Evol ; 25(6): 1209-18, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18359946

RESUMO

Modern humans have been living in Island Southeast Asia (ISEA) for at least 50,000 years. Largely because of the influence of linguistic studies, however, which have a shallow time depth, the attention of archaeologists and geneticists has usually been focused on the last 6,000 years--in particular, on a proposed Neolithic dispersal from China and Taiwan. Here we use complete mitochondrial DNA (mtDNA) genome sequencing to spotlight some earlier processes that clearly had a major role in the demographic history of the region but have hitherto been unrecognized. We show that haplogroup E, an important component of mtDNA diversity in the region, evolved in situ over the last 35,000 years and expanded dramatically throughout ISEA around the beginning of the Holocene, at the time when the ancient continent of Sundaland was being broken up into the present-day archipelago by rising sea levels. It reached Taiwan and Near Oceania more recently, within the last approximately 8,000 years. This suggests that global warming and sea-level rises at the end of the Ice Age, 15,000-7,000 years ago, were the main forces shaping modern human diversity in the region.


Assuntos
DNA Mitocondrial/genética , Emigração e Imigração , Efeito Estufa , Camada de Gelo , Sudeste Asiático , Sequência de Bases , DNA Mitocondrial/classificação , DNA Mitocondrial/história , Emigração e Imigração/história , Variação Genética , Haplótipos , História Antiga , Humanos , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA
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