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1.
Addict Behav ; 155: 108025, 2024 08.
Artigo em Inglês | MEDLINE | ID: mdl-38593596

RESUMO

BACKGROUND: People in substance use disorder (SUD) treatment have a smoking prevalence that is five times higher than the national average. California funded the Tobacco Free for Recovery Initiative, designed to support programs in implementing tobacco-free grounds and increasing smoking cessation services. In the first cohort of the initiative (2018-2020) client smoking prevalence decreased from 54.2% to 26.6%. The current study examined whether similar findings would be replicated with a later cohort of programs (2020-2022). METHOD: Cross-sectional survey data were collected from clients in 11 residential SUD treatment programs at baseline (n = 185) and at post intervention (n = 227). Multivariate logistic regression assessed change over time in smoking prevalence, tobacco use behaviors, and receipt of cessation services across the two timepoints. RESULTS: Client smoking prevalence decreased from 60.3 % to 40.5 % (Adjusted Odds Ratio [AOR] = 0.46, 95 % CI = 0.27, 0.78; p = 0.004). Current smokers and those who quit while in treatment reported an increase in nicotine replacement therapy (NRT)/pharmacotherapy from baseline to post intervention (31.9 % vs 45.6 %; AOR = 2.22, 95 % CI = 1.08, 4.58; p = 0.031). CONCLUSIONS: Like the first cohort, the Tobacco Free for Recovery initiative was associated with decreased client smoking prevalence and an increase in NRT/pharmacotherapy. These findings strengthen the evidence that similar initiatives may be effective in reducing smoking prevalence among people in SUD treatment.


Assuntos
Abandono do Hábito de Fumar , Transtornos Relacionados ao Uso de Substâncias , Humanos , California/epidemiologia , Masculino , Feminino , Adulto , Abandono do Hábito de Fumar/métodos , Abandono do Hábito de Fumar/estatística & dados numéricos , Estudos Transversais , Pessoa de Meia-Idade , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/terapia , Prevalência , Dispositivos para o Abandono do Uso de Tabaco/estatística & dados numéricos , Tratamento Domiciliar
2.
Nature ; 627(8002): 196-203, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38355805

RESUMO

It is well established that neutrophils adopt malleable polymorphonuclear shapes to migrate through narrow interstitial tissue spaces1-3. However, how polymorphonuclear structures are assembled remains unknown4. Here we show that in neutrophil progenitors, halting loop extrusion-a motor-powered process that generates DNA loops by pulling in chromatin5-leads to the assembly of polymorphonuclear genomes. Specifically, we found that in mononuclear neutrophil progenitors, acute depletion of the loop-extrusion loading factor nipped-B-like protein (NIPBL) induced the assembly of horseshoe, banded, ringed and hypersegmented nuclear structures and led to a reduction in nuclear volume, mirroring what is observed during the differentiation of neutrophils. Depletion of NIPBL also induced cell-cycle arrest, activated a neutrophil-specific gene program and conditioned a loss of interactions across topologically associating domains to generate a chromatin architecture that resembled that of differentiated neutrophils. Removing NIPBL resulted in enrichment for mega-loops and interchromosomal hubs that contain genes associated with neutrophil-specific enhancer repertoires and an inflammatory gene program. On the basis of these observations, we propose that in neutrophil progenitors, loop-extrusion programs produce lineage-specific chromatin architectures that permit the packing of chromosomes into geometrically confined lobular structures. Our data also provide a blueprint for the assembly of polymorphonuclear structures, and point to the possibility of engineering de novo nuclear shapes to facilitate the migration of effector cells in densely populated tumorigenic environments.


Assuntos
Movimento Celular , Forma do Núcleo Celular , Neutrófilos , Pontos de Checagem do Ciclo Celular , Proteínas de Ciclo Celular/deficiência , Proteínas de Ciclo Celular/metabolismo , Cromatina/química , Cromatina/metabolismo , Cromossomos/química , Cromossomos/metabolismo , Neutrófilos/citologia , Neutrófilos/metabolismo , Conformação de Ácido Nucleico , Diferenciação Celular/genética , Inflamação/genética , Elementos Facilitadores Genéticos , Linhagem da Célula/genética
3.
Sci Rep ; 13(1): 21033, 2023 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-38030652

RESUMO

Transitions to physically different environments, such as the water-to-land transition, proved to be the main drivers of relevant evolutionary events. Brachyuran crabs evolved remarkable morphological, behavioral, and physiological adaptations to terrestrial life. Terrestrial species evolved new respiratory structures devoted to replace or support the gills, a multifunctional organ devoted to gas exchanges, ion-regulation and nitrogen excretion. It was hypothesized that microorganisms associated with respiratory apparatus could have facilitated the processes of osmoregulation, respiration, and elimination of metabolites along this evolutionary transition. To test if crab species with different breathing adaptations may host similar microbial communities on their gills, we performed a comparative targeted-metagenomic analysis, selecting two marine and six terrestrial crabs belonging to different families and characterised by different breathing adaptations. We analysed anterior and posterior gills separately according to their different and specific roles. Regardless of their terrestrial or marine adaptations, microbial assemblages were strongly species-specific indicating a non-random association between the host and its microbiome. Significant differences were found in only two terrestrial species when considering posterior vs. anterior gills, without any association with species-specific respiratory adaptations. Our results suggest that all the selected species are strongly adapted to the ecological niche and specific micro-habitat they colonise.


Assuntos
Braquiúros , Microbiota , Humanos , Animais , Braquiúros/fisiologia , Brânquias/metabolismo , Respiração , Taxa Respiratória
4.
Front Microbiol ; 14: 1113617, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37378290

RESUMO

Microorganisms are ubiquitous in the environment and provide genetic and physiological functions to multicellular organisms. Knowledge on the associated microbiota is becoming highly relevant to understand the host's ecology and biology. Among invertebrates, many examples of endosymbiosis have been described, such as those in corals, ants, and termites. At present, however, little is known on the presence, diversity, and putative roles of the microbiota associated to brachyuran crabs in relation to their environment. In this work we investigated the associated microbiota of three populations of the terrestrial brachyuran crab Chiromantes haematocheir to find evidence of a conserved organ-specific microbiome unrelated to the population of origin and dissimilar from environmental microbial assemblages. Bacterial 16S rRNA gene and fungal ITS sequences were obtained from selected crab organs and environmental matrices to profile microbial communities. Despite the presence of truly marine larval stages and the absence of a gregarious behaviour, favouring microbiota exchanges, we found common, organ-specific microbiota, associated with the gut and the gills of crabs from the different populations (with more than 15% of the genera detected specifically enriched only in one organ). These findings suggest the presence of possible functional roles of the organ-specific microbiota.

5.
Viruses ; 15(2)2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36851631

RESUMO

Of the 12 million people who inject drugs worldwide, 13% live with HIV. Whether opioid use impacts HIV pathogenesis and latency is an outstanding question. To gain insight into whether opioid use influences the proviral landscape and latent HIV reservoir, we performed intact proviral DNA assays (IPDA) on peripheral blood mononuclear cells (PBMCs) from antiretroviral therapy (ART)-suppressed people living with HIV (PWH) with or without current opioid use. No differences were observed between PWH with and without opioid use in the frequency of HIV intact and defective proviral genomes. To evaluate the latent reservoir, we activated PBMCs from ART-suppressed PWH with or without opioid use and assessed the induction of HIV RNA. PWH using opioids had diminished responses to ex vivo HIV reactivation, suggesting a smaller reversible reservoir of HIV-1 latently infected cells. However, in vitro studies using primary CD4+ T cells treated with morphine showed no effect of opioids on HIV-1 infection, replication or latency establishment. The discrepancy in our results from in vitro and clinical samples suggests that while opioids may not directly impact HIV replication, latency and reactivation in CD4+ T cells, opioid use may indirectly shape the HIV reservoir in vivo by modulating general immune functions.


Assuntos
Infecções por HIV , HIV-1 , Humanos , Analgésicos Opioides/farmacologia , Infecções por HIV/tratamento farmacológico , Leucócitos Mononucleares , Latência Viral , Provírus/genética
6.
Nat Commun ; 13(1): 6275, 2022 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-36271092

RESUMO

The use of iPSC derived brain organoid models to study neurodegenerative disease has been hampered by a lack of systems that accurately and expeditiously recapitulate pathogenesis in the context of neuron-glial interactions. Here we report development of a system, termed AstTau, which propagates toxic human tau oligomers in iPSC derived neuron-astrocyte assembloids. The AstTau system develops much of the neuronal and astrocytic pathology observed in tauopathies including misfolded, phosphorylated, oligomeric, and fibrillar tau, strong neurodegeneration, and reactive astrogliosis. Single cell transcriptomic profiling combined with immunochemistry characterizes a model system that can more closely recapitulate late-stage changes in adult neurodegeneration. The transcriptomic studies demonstrate striking changes in neuroinflammatory and heat shock protein (HSP) chaperone systems in the disease process. Treatment with the HSP90 inhibitor PU-H71 is used to address the putative dysfunctional HSP chaperone system and produces a strong reduction of pathology and neurodegeneration, highlighting the potential of AstTau as a rapid and reproducible tool for drug discovery.


Assuntos
Doenças Neurodegenerativas , Tauopatias , Humanos , Astrócitos/metabolismo , Proteínas tau/genética , Proteínas tau/metabolismo , Doenças Neurodegenerativas/metabolismo , Transcriptoma , Tauopatias/metabolismo , Neurônios/metabolismo , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo
7.
Am J Physiol Endocrinol Metab ; 323(2): E123-E132, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35723225

RESUMO

Fibroblast growth factor 21 (FGF21) is increased acutely by carbohydrate ingestion and is elevated in patients with type 2 diabetes (T2D). However, the physiological significance of increased FGF21 in humans remains largely unknown. We examined whether FGF21 contributed to the metabolic improvements observed following treatment of patients with T2D with either triple (metformin/pioglitazone/exenatide) or conventional (metformin/insulin/glipizide) therapy for 3 yr. Forty-six patients with T2D were randomized to receive either triple or conventional therapy to maintain HbA1c < 6.5%. A 2-h 75-g oral glucose tolerance test (OGTT) was performed at baseline and following 3 years of treatment to assess glucose tolerance, insulin sensitivity, and ß-cell function. Plasma total and bioactive FGF21 levels were quantitated before and during the OGTT at both visits. Patients in both treatment arms experienced significant improvements in glucose control, but insulin sensitivity and ß-cell function were markedly increased after triple therapy. At baseline, FGF21 levels were regulated acutely during the OGTT in both groups. After treatment, fasting total and bioactive FGF21 levels were significantly reduced in patients receiving triple therapy, but there was a relative increase in the proportion of bioactive FGF21 compared with that observed in conventionally treated subjects. Relative to baseline studies, triple therapy treatment also significantly modified FGF21 levels in response to a glucose load. These changes in circulating FGF21 were correlated with markers of improved glucose control and insulin sensitivity. Alterations in the plasma FGF21 profile may contribute to the beneficial metabolic effects of pioglitazone and exenatide in human patients with T2D.NEW & NOTEWORTHY In patients with T2D treated with a combination of metformin/pioglitazone/exenatide (triple therapy), we observed reduced total and bioactive plasma FGF21 levels and a relative increase in the proportion of circulating bioactive FGF21 compared with that in patients treated with metformin and sequential addition of glipizide and basal insulin glargine (conventional therapy). These data suggest that FGF21 may contribute, at least in part, to the glycemic benefits observed following combination therapy in patients with T2D.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Metformina , Tiazolidinedionas , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Exenatida , Fatores de Crescimento de Fibroblastos , Glipizida , Hemoglobinas Glicadas/metabolismo , Humanos , Hipoglicemiantes/uso terapêutico , Metformina/uso terapêutico , Peptídeos , Pioglitazona , Peçonhas
8.
PLoS Genet ; 17(11): e1009854, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34723967

RESUMO

The forkhead box (Fox) family of transcription factors are highly conserved and play essential roles in a wide range of cellular and developmental processes. We report an individual with severe neurological symptoms including postnatal microcephaly, progressive brain atrophy and global developmental delay associated with a de novo missense variant (M280L) in the FOXR1 gene. At the protein level, M280L impaired FOXR1 expression and induced a nuclear aggregate phenotype due to protein misfolding and proteolysis. RNAseq and pathway analysis showed that FOXR1 acts as a transcriptional activator and repressor with central roles in heat shock response, chaperone cofactor-dependent protein refolding and cellular response to stress pathways. Indeed, FOXR1 expression is increased in response to cellular stress, a process in which it directly controls HSPA6, HSPA1A and DHRS2 transcripts. The M280L mutant compromises FOXR1's ability to respond to stress, in part due to impaired regulation of downstream target genes that are involved in the stress response pathway. Quantitative PCR of mouse embryo tissues show Foxr1 expression in the embryonic brain. Using CRISPR/Cas9 gene editing, we found that deletion of mouse Foxr1 leads to a severe survival deficit while surviving newborn Foxr1 knockout mice have reduced body weight. Further examination of newborn Foxr1 knockout brains revealed a decrease in cortical thickness and enlarged ventricles compared to littermate wild-type mice, suggesting that loss of Foxr1 leads to atypical brain development. Combined, these results suggest FOXR1 plays a role in cellular stress response pathways and is necessary for normal brain development.


Assuntos
Encéfalo/crescimento & desenvolvimento , Fatores de Transcrição Forkhead/fisiologia , Estresse Fisiológico , Animais , Feminino , Fatores de Transcrição Forkhead/genética , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Knockout , Mutação de Sentido Incorreto , Fenótipo
9.
BMC Ecol Evol ; 21(1): 180, 2021 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-34556035

RESUMO

BACKGROUND: Mangroves are tropical and subtropical intertidal forests colonising sheltered coasts across the world. They host a unique faunal community, dominated by brachyuran crabs and gastropods. These invertebrates strongly contribute to the functionality of the entire forest. The reliable assessment of mangrove faunal diversity is, thus, a crucial step for efficient management and conservation plans, but it is hindered by difficulties in species identification. Here we provide a verified DNA barcode library for brachyuran crabs and gastropods inhabiting the mangroves of the Greater Bay Area, Southern China. In particular, we collected and morphologically identified 1100 specimens of mangrove associated brachyuran crabs and gastropods. The partial sequences of the mtDNA cytochrome oxidase subunit I gene were obtained from 275 specimens. Barcode sequences were then used to delineate Molecular Operational Taxonomic Units (MOTUs), employing three different delimitation methods: the automatic barcode gap discovery (ABGD) method, the general mixed Yule coalescent (GMYC) model and a Bayesian implementation of the Poisson tree processes (bPTP) model. RESULTS: By integrating DNA barcodes with morphology, we identified 44 gastropod species and 58 brachyuran species associated with Hong Kong mangroves, with five and seven new records, for gastropods and crabs, respectively, for the Greater Bay Area. The delineation of MOTUs based on barcode sequences revealed a strong congruence between morphological and molecular identification for both taxa, showing the high reliability of the barcode library. CONCLUSIONS: This study provides the first reference barcode library for mangrove-associated macrobenthic fauna in the Greater Bay Area and represents a reliable tool to management and conservation plans. Our molecular analyses resolved long lasting taxonomic misidentifications and inconsistencies and updated the knowledge on the geographical distribution of Asian mangrove associated fauna, ultimately highlighting a level of biodiversity higher than previously thought for Southern China.


Assuntos
Braquiúros , Gastrópodes , Animais , Teorema de Bayes , Braquiúros/genética , China , Código de Barras de DNA Taxonômico , Florestas , Gastrópodes/genética , Hong Kong , Filogenia , Reprodutibilidade dos Testes
10.
J Clin Invest ; 131(12)2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34003802

RESUMO

Tirzepatide (LY3298176), a dual GIP and GLP-1 receptor (GLP-1R) agonist, delivered superior glycemic control and weight loss compared with GLP-1R agonism in patients with type 2 diabetes. However, the mechanism by which tirzepatide improves efficacy and how GIP receptor (GIPR) agonism contributes is not fully understood. Here, we show that tirzepatide is an effective insulin sensitizer, improving insulin sensitivity in obese mice to a greater extent than GLP-1R agonism. To determine whether GIPR agonism contributes, we compared the effect of tirzepatide in obese WT and Glp-1r-null mice. In the absence of GLP-1R-induced weight loss, tirzepatide improved insulin sensitivity by enhancing glucose disposal in white adipose tissue (WAT). In support of this, a long-acting GIPR agonist (LAGIPRA) was found to enhance insulin sensitivity by augmenting glucose disposal in WAT. Interestingly, the effect of tirzepatide and LAGIPRA on insulin sensitivity was associated with reduced branched-chain amino acids (BCAAs) and ketoacids in the circulation. Insulin sensitization was associated with upregulation of genes associated with the catabolism of glucose, lipid, and BCAAs in brown adipose tissue. Together, our studies show that tirzepatide improved insulin sensitivity in a weight-dependent and -independent manner. These results highlight how GIPR agonism contributes to the therapeutic profile of dual-receptor agonism, offering mechanistic insights into the clinical efficacy of tirzepatide.


Assuntos
Tecido Adiposo Branco/metabolismo , Polipeptídeo Inibidor Gástrico/farmacologia , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Resistência à Insulina , Obesidade/metabolismo , Tecido Adiposo Branco/patologia , Aminoácidos de Cadeia Ramificada/genética , Aminoácidos de Cadeia Ramificada/metabolismo , Animais , Peso Corporal/efeitos dos fármacos , Peso Corporal/genética , Receptor do Peptídeo Semelhante ao Glucagon 1/genética , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Camundongos , Camundongos Knockout , Obesidade/tratamento farmacológico , Obesidade/genética , Obesidade/patologia
11.
Ann Pharmacother ; 55(10): 1185-1194, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33384014

RESUMO

BACKGROUND: The US Food and Drug Administration (FDA) recommends using only FDA-reviewed pharmacogenetic information to make prescribing decisions based on genetic test results. Such information is available in drug labeling and in the Table of Pharmacogenetic Associations ("Associations table"). OBJECTIVE: To compile a list of drug-gene pairs from drug labeling and the Associations table and categorize the pharmacogenetic information and clinical outcome associated with each drug-gene pair. METHODS: This was a cross-sectional analysis of pharmacogenetic information in the Associations table and individual drug labeling in March 2020. We used the Table of Pharmacogenomic Biomarkers in Drug Labeling to identify drug labels to review. We categorized the pharmacogenetic information for each drug-gene pair according to whether the purpose was to describe (1) polymorphisms affecting drug disposition (metabolism or transport), (2) polymorphisms affecting a direct drug target, (3) variants associated with adverse drug reaction (ADR) susceptibility, (4) variants associated with therapeutic failure, (5) a biomarker-defined indication, or (6) a biomarker-defined ADR. We also categorized the clinical outcome-efficacy, safety, or unknown-associated with each drug-gene pair. We reported counts and proportions of drug-gene pairs in each pharmacogenetic information and clinical outcome category. RESULTS: We identified 308 drug-gene pairs, of which 36% were associated with a biomarker-defined drug indication, 33% with polymorphic drug metabolism, and 28% with ADR susceptibility. Most drug-gene pairs (n = 267, 87%) were associated with an efficacy or safety-related outcome. CONCLUSION AND RELEVANCE: FDA-reviewed pharmacogenetic information is available for more than 300 drug-gene pairs and can help guide prescribing decisions.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Farmacogenética , Estudos Transversais , Rotulagem de Medicamentos , Humanos , Estados Unidos , United States Food and Drug Administration
12.
Nat Commun ; 11(1): 2611, 2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32457298

RESUMO

Chronic opioid usage not only causes addiction behavior through the central nervous system, but also modulates the peripheral immune system. However, how opioid impacts the immune system is still barely characterized systematically. In order to understand the immune modulatory effect of opioids in an unbiased way, here we perform single-cell RNA sequencing (scRNA-seq) of peripheral blood mononuclear cells from opioid-dependent individuals and controls to show that chronic opioid usage evokes widespread suppression of antiviral gene program in naive monocytes, as well as in multiple immune cell types upon stimulation with the pathogen component lipopolysaccharide. Furthermore, scRNA-seq reveals the same phenomenon after a short in vitro morphine treatment. These findings indicate that both acute and chronic opioid exposure may be harmful to our immune system by suppressing the antiviral gene program. Our results suggest that further characterization of the immune modulatory effects of opioid is critical to ensure the safety of clinical opioids.


Assuntos
Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Transtornos Relacionados ao Uso de Opioides/imunologia , Viroses/imunologia , Adulto , Antivirais/farmacologia , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Interferons/farmacologia , Leucócitos Mononucleares , Lipopolissacarídeos/farmacologia , Masculino , Pessoa de Meia-Idade , Morfina/farmacologia , Análise de Célula Única , Adulto Jovem
13.
Int J Obes (Lond) ; 44(2): 544-547, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31455871

RESUMO

Fibroblast growth factor 21 (FGF21) is an important regulator of energy metabolism. FGF21 is inactivated by fibroblast activation protein (FAP). We investigated whether FGF21 and/or FAP are secreted from human white adipose tissue of individuals with obesity by measuring total FGF21, active FGF21, and FAP concentrations in arterialized blood and venous blood draining the subcutaneous abdominal adipose tissue (scAT). Measurements were performed under fasting conditions and after a high fat meal before and after diet-induced weight loss in 16 adults with BMI 27-35 kg/m2. FGF21 was not released from scAT, neither before nor after weight loss in agreement with an undetectable gene expression of FGF21 in this tissue. Although scAT showed significant gene expression of FAP, no release of FAP from the tissue could be detected. The high fat meal increased postprandial circulating FGF21 but not FAP. Circulating levels of FAP but not FGF21 were significantly reduced after weight loss. On the other hand, FAP expression in scAT was increased. In conclusion, release from scAT does not appear to contribute to circulating concentrations of FGF21 and FAP and their responses to ingestion of a high fat meal or weight loss, respectively, in individuals with obesity.


Assuntos
Fatores de Crescimento de Fibroblastos/sangue , Gelatinases/sangue , Proteínas de Membrana/sangue , Obesidade , Serina Endopeptidases/sangue , Gordura Subcutânea Abdominal/metabolismo , Adulto , Dieta Redutora , Endopeptidases , Humanos , Obesidade/sangue , Obesidade/dietoterapia , Obesidade/metabolismo
14.
J Vis Exp ; (145)2019 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-30958473

RESUMO

ATAC-seq has become a widely used methodology in the study of epigenetics due to its rapid and simple approach to mapping genome-wide accessible chromatin. In this paper we present an improved ATAC-seq protocol that reduces contaminating mitochondrial DNA reads. While previous ATAC-seq protocols have struggled with an average of 50% contaminating mitochondrial DNA reads, the optimized lysis buffer introduced in this protocol reduces mitochondrial DNA contamination to an average of 3%. This improved ATAC-seq protocol allows for a near 50% reduction in the sequencing cost. We demonstrate how these high-quality ATAC-seq libraries can be prepared from activated CD4+ lymphocytes, providing step-by-step instructions from CD4+ lymphocyte isolation from whole blood through data analysis. This improved ATAC-seq protocol has been validated in a wide range of cell types and will be of immediate use to researchers studying chromatin accessibility.


Assuntos
Linfócitos T CD4-Positivos/metabolismo , Cromatina/genética , Contaminação por DNA , DNA Mitocondrial/genética , Análise de Sequência de DNA/métodos , Transposases/metabolismo , Mapeamento Cromossômico , Humanos
15.
Methods Cell Biol ; 148: 161-176, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30473068

RESUMO

For many engineering applications such as manipulating two phase flows, generating single and double emulsions, and passively propelling liquids through channels, control over the surface energy of microfluidic channels is essential. In particular, double emulsion formation, which benefits from alternating hydrophobic and hydrophilic sections of channel, represents a challenge in fabricating controlled microfluidic channel surface properties. As double emulsions find further applications in single-cell handling and analysis, straightforward methods for generating them increase in value. Here, we present a method for generating double emulsions in microfluidic channels fabricated from modular fluidic blocks. By using a vapor-phase polymer coating technology-initiated chemical vapor deposition-we are able to fabricate blocks with varying surface properties. Assembling these blocks together then creates step-like changes in surface energy within a microchannel.


Assuntos
Emulsões/química , Técnicas Analíticas Microfluídicas/métodos , Propriedades de Superfície
16.
Nat Genet ; 50(8): 1140-1150, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29988122

RESUMO

Over 90% of genetic variants associated with complex human traits map to non-coding regions, but little is understood about how they modulate gene regulation in health and disease. One possible mechanism is that genetic variants affect the activity of one or more cis-regulatory elements leading to gene expression variation in specific cell types. To identify such cases, we analyzed ATAC-seq and RNA-seq profiles from stimulated primary CD4+ T cells in up to 105 healthy donors. We found that regions of accessible chromatin (ATAC-peaks) are co-accessible at kilobase and megabase resolution, consistent with the three-dimensional chromatin organization measured by in situ Hi-C in T cells. Fifteen percent of genetic variants located within ATAC-peaks affected the accessibility of the corresponding peak (local-ATAC-QTLs). Local-ATAC-QTLs have the largest effects on co-accessible peaks, are associated with gene expression and are enriched for autoimmune disease variants. Our results provide insights into how natural genetic variants modulate cis-regulatory elements, in isolation or in concert, to influence gene expression.


Assuntos
Linfócitos T CD4-Positivos/fisiologia , Cromatina/genética , Polimorfismo de Nucleotídeo Único , Adulto , Doenças Autoimunes/genética , Feminino , Regulação da Expressão Gênica , Genótipo , Humanos , Masculino , Sequências Reguladoras de Ácido Nucleico
17.
Cell ; 174(3): 744-757.e24, 2018 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-29887377

RESUMO

Eukaryotic genomes are packaged into a 3-dimensional structure in the nucleus. Current methods for studying genome-wide structure are based on proximity ligation. However, this approach can fail to detect known structures, such as interactions with nuclear bodies, because these DNA regions can be too far apart to directly ligate. Accordingly, our overall understanding of genome organization remains incomplete. Here, we develop split-pool recognition of interactions by tag extension (SPRITE), a method that enables genome-wide detection of higher-order interactions within the nucleus. Using SPRITE, we recapitulate known structures identified by proximity ligation and identify additional interactions occurring across larger distances, including two hubs of inter-chromosomal interactions that are arranged around the nucleolus and nuclear speckles. We show that a substantial fraction of the genome exhibits preferential organization relative to these nuclear bodies. Our results generate a global model whereby nuclear bodies act as inter-chromosomal hubs that shape the overall packaging of DNA in the nucleus.


Assuntos
Núcleo Celular/ultraestrutura , Mapeamento Cromossômico/métodos , Cromossomos/fisiologia , Nucléolo Celular , Núcleo Celular/fisiologia , Cromossomos/genética , DNA/fisiologia , Eucariotos , Genoma/genética , Genoma/fisiologia , Humanos , Relação Estrutura-Atividade
18.
Angew Chem Int Ed Engl ; 57(31): 9670-9674, 2018 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-29870587

RESUMO

Toward nitrogen functionalization, reactive terminal transition metal nitrides with high d-electron counts are of interest. A series of terminal MoIV nitride complexes were prepared within the context of exploring nitride/carbonyl coupling to cyanate. Reduction affords the first MoII nitrido complex, an early metal nitride with four valence d-electrons. The binding mode of the para-terphenyl diphosphine ancillary ligand changes to stabilize an electronic configuration with a high electron count and a formal M-N bond order of three. Even with an intact Mo≡N bond, this low-valent nitrido complex proves to be highly reactive, readily undergoing N-atom transfer upon addition of CO, releasing cyanate anion.

19.
Nat Commun ; 9(1): 2068, 2018 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-29802342

RESUMO

Transient activation of Src oncoprotein in non-transformed, breast epithelial cells can initiate an epigenetic switch to the stably transformed state via a positive feedback loop that involves the inflammatory transcription factors STAT3 and NF-κB. Here, we develop an experimental and computational pipeline that includes 1) a Bayesian network model (AccessTF) that accurately predicts protein-bound DNA sequence motifs based on chromatin accessibility, and 2) a scoring system (TFScore) that rank-orders transcription factors as candidates for being important for a biological process. Genetic experiments validate TFScore and suggest that more than 40 transcription factors contribute to the oncogenic state in this model. Interestingly, individual depletion of several of these factors results in similar transcriptional profiles, indicating that a complex and interconnected transcriptional network promotes a stable oncogenic state. The combined experimental and computational pipeline represents a general approach to comprehensively identify transcriptional regulators important for a biological process.


Assuntos
Neoplasias da Mama/genética , Transformação Celular Neoplásica/genética , Epigênese Genética , Regulação Neoplásica da Expressão Gênica/genética , Fatores de Transcrição/metabolismo , Mama/citologia , Mama/patologia , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Perfilação da Expressão Gênica , Redes Reguladoras de Genes/genética , Genoma Humano/genética , Humanos , Modelos Genéticos , Fatores de Transcrição/genética
20.
J Am Med Inform Assoc ; 25(7): 872-884, 2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-29800453

RESUMO

Objective: To extract drug indications from a commercial drug knowledgebase and determine to what extent drug indications can discriminate between look-alike-sound-alike (LASA) drugs. Methods: We extracted drug indications disease concepts from the MedKnowledge Indications module from First Databank Inc. (South San Francisco, CA) and associated them with drugs on the Institute for Safe Medication Practices (ISMP) list of commonly confused drug names. We used high-level concepts (rather than granular concepts) to represent the general indications for each drug. Two pharmacists reviewed each drug's association with its high-level indications concepts for accuracy and clinical relevance. We compared the high-level indications for each commonly confused drug pair and categorized each pair as having a complete overlap, partial overlap or no overlap in high-level indications. Results: Of 278 LASA drug pairs, 165 (59%) had no overlap and 58 (21%) had partial overlap in high-level indications. Fifty-five pairs (20%) had complete overlap in high-level indications; nearly half of these were comprised of drugs with the same active ingredient and route of administration (e.g., Adderall, Adderall XR). Conclusions: Drug indications data from a drug knowledgebase can discriminate between many LASA drugs.


Assuntos
Bases de Conhecimento , Erros de Medicação/prevenção & controle , Preparações Farmacêuticas , Terminologia como Assunto , Prescrições de Medicamentos , Humanos
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