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Determining protein levels in each tissue and how they compare with RNA levels is important for understanding human biology and disease as well as regulatory processes that control protein levels. We quantified the relative protein levels from over 12,000 genes across 32 normal human tissues. Tissue-specific or tissue-enriched proteins were identified and compared to transcriptome data. Many ubiquitous transcripts are found to encode tissue-specific proteins. Discordance of RNA and protein enrichment revealed potential sites of synthesis and action of secreted proteins. The tissue-specific distribution of proteins also provides an in-depth view of complex biological events that require the interplay of multiple tissues. Most importantly, our study demonstrated that protein tissue-enrichment information can explain phenotypes of genetic diseases, which cannot be obtained by transcript information alone. Overall, our results demonstrate how understanding protein levels can provide insights into regulation, secretome, metabolism, and human diseases.
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Proteoma/genética , Proteômica/métodos , Transcriptoma/genética , Expressão Gênica/genética , Perfilação da Expressão Gênica/métodos , Humanos , Proteoma/fisiologia , RNA/genética , RNA Mensageiro/metabolismo , Transcriptoma/fisiologiaRESUMO
I am deeply honored to be invited to write this scientific autobiography. As a physician-scientist, pediatrician, molecular biologist, and geneticist, I have authored/coauthored more than 600 publications in the fields of clinical medicine, biochemistry, biophysics, pharmacology, drug metabolism, toxicology, molecular biology, cancer, standardized gene nomenclature, developmental toxicology and teratogenesis, mouse genetics, human genetics, and evolutionary genomics. Looking back, I think my career can be divided into four distinct research areas, which I summarize mostly chronologically in this article: (a) discovery and characterization of the AHR/CYP1 axis, (b) pharmacogenomics and genetic prediction of response to drugs and other environmental toxicants, (c) standardized drug-metabolizing gene nomenclature based on evolutionary divergence, and (d) discovery and characterization of the SLC39A8 gene encoding the ZIP8 metal cation influx transporter. Collectively, all four topics embrace gene-environment interactions, hence the title of my autobiography.
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Genômica , Médicos , Humanos , Animais , Camundongos , Proteínas de Membrana Transportadoras , FarmacogenéticaRESUMO
Wildfires have become more frequent and intense due to climate change and outdoor wildfire fine particulate matter (PM2.5) concentrations differ from relatively smoothly varying total PM2.5. Thus, we introduced a conceptual model for computing long-term wildfire PM2.5 and assessed disproportionate exposures among marginalized communities. We used monitoring data and statistical techniques to characterize annual wildfire PM2.5 exposure based on intermittent and extreme daily wildfire PM2.5 concentrations in California census tracts (2006 to 2020). Metrics included: 1) weeks with wildfire PM2.5 < 5 µg/m3; 2) days with non-zero wildfire PM2.5; 3) mean wildfire PM2.5 during peak exposure week; 4) smoke waves (≥2 consecutive days with <15 µg/m3 wildfire PM2.5); and 5) mean annual wildfire PM2.5 concentration. We classified tracts by their racial/ethnic composition and CalEnviroScreen (CES) score, an environmental and social vulnerability composite measure. We examined associations of CES and racial/ethnic composition with the wildfire PM2.5 metrics using mixed-effects models. Averaged 2006 to 2020, we detected little difference in exposure by CES score or racial/ethnic composition, except for non-Hispanic American Indian and Alaska Native populations, where a 1-SD increase was associated with higher exposure for 4/5 metrics. CES or racial/ethnic × year interaction term models revealed exposure disparities in some years. Compared to their California-wide representation, the exposed populations of non-Hispanic American Indian and Alaska Native (1.68×, 95% CI: 1.01 to 2.81), white (1.13×, 95% CI: 0.99 to 1.32), and multiracial (1.06×, 95% CI: 0.97 to 1.23) people were over-represented from 2006 to 2020. In conclusion, during our study period in California, we detected disproportionate long-term wildfire PM2.5 exposure for several racial/ethnic groups.
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Poluentes Atmosféricos , Incêndios Florestais , Humanos , Material Particulado/efeitos adversos , Fumaça/efeitos adversos , California , Grupos Raciais , Exposição Ambiental , Poluentes Atmosféricos/efeitos adversosRESUMO
The diagnosis of primary lung adenocarcinomas with intestinal or mucinous differentiation (PAIM) remains challenging due to the overlapping histomorphological, immunohistochemical (IHC), and genetic characteristics with lung metastatic colorectal cancer (lmCRC). This study aimed to explore the protein biomarkers that could distinguish between PAIM and lmCRC. To uncover differences between the two diseases, we used tandem mass tagging-based shotgun proteomics to characterize proteomes of formalin-fixed, paraffin-embedded tumor samples of PAIM (n = 22) and lmCRC (n = 17).Then three machine learning algorithms, namely support vector machine (SVM), random forest, and the Least Absolute Shrinkage and Selection Operator, were utilized to select protein features with diagnostic significance. These candidate proteins were further validated in an independent cohort (PAIM, n = 11; lmCRC, n = 19) by IHC to confirm their diagnostic performance. In total, 105 proteins out of 7871 proteins were significantly dysregulated between PAIM and lmCRC samples and well-separated two groups by Uniform Manifold Approximation and Projection. The upregulated proteins in PAIM were involved in actin cytoskeleton organization, platelet degranulation, and regulation of leukocyte chemotaxis, while downregulated ones were involved in mitochondrial transmembrane transport, vasculature development, and stem cell proliferation. A set of ten candidate proteins (high-level expression in lmCRC: CDH17, ATP1B3, GLB1, OXNAD1, LYST, FABP1; high-level expression in PAIM: CK7 (an established marker), NARR, MLPH, S100A14) was ultimately selected to distinguish PAIM from lmCRC by machine learning algorithms. We further confirmed using IHC that the five protein biomarkers including CDH17, CK7, MLPH, FABP1 and NARR were effective biomarkers for distinguishing PAIM from lmCRC. Our study depicts PAIM-specific proteomic characteristics and demonstrates the potential utility of new protein biomarkers for the differential diagnosis of PAIM and lmCRC. These findings may contribute to improving the diagnostic accuracy and guide appropriate treatments for these patients.
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Adenocarcinoma de Pulmão , Biomarcadores Tumorais , Neoplasias Colorretais , Neoplasias Pulmonares , Proteômica , Humanos , Biomarcadores Tumorais/metabolismo , Proteômica/métodos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Adenocarcinoma de Pulmão/metabolismo , Adenocarcinoma de Pulmão/patologia , Masculino , Feminino , Diagnóstico Diferencial , Diferenciação Celular , Pessoa de Meia-Idade , Idoso , Adenocarcinoma/metabolismo , Adenocarcinoma/patologiaRESUMO
Foraging theory prescribes when optimal foragers should leave the current option for more rewarding alternatives. Actual foragers often exploit options longer than prescribed by the theory, but it is unclear how this foraging suboptimality arises. We investigated whether the upregulation of cholinergic, noradrenergic, and dopaminergic systems increases foraging optimality. In a double-blind, between-subject design, participants (N = 160) received placebo, the nicotinic acetylcholine receptor agonist nicotine, a noradrenaline reuptake inhibitor reboxetine, or a preferential dopamine reuptake inhibitor methylphenidate, and played the role of a farmer who collected milk from patches with different yield. Across all groups, participants on average overharvested. While methylphenidate had no effects on this bias, nicotine, and to some extent also reboxetine, significantly reduced deviation from foraging optimality, which resulted in better performance compared to placebo. Concurring with amplified goal-directedness and excluding heuristic explanations, nicotine independently also improved trial initiation and time perception. Our findings elucidate the neurochemical basis of behavioral flexibility and decision optimality and open unique perspectives on psychiatric disorders affecting these functions.
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Acetilcolina , Metilfenidato , Humanos , Nicotina/farmacologia , Norepinefrina , Reboxetina , Método Duplo-CegoRESUMO
The use of electronic (e)-cigarettes was initially considered a beneficial solution to conventional cigarette smoking cessation. However, paradoxically, e-cigarette use is rapidly growing among nonsmokers, including youth and young adults. In 2019, this rapid growth resulted in an epidemic of hospitalizations and deaths of e-cigarette users (vapers) due to acute lung injury; this novel disease was termed e-cigarette or vaping use-associated lung injury (EVALI). Pathophysiologic mechanisms of EVALI likely involve cytotoxicity and neutrophilic inflammation caused by inhaled chemicals, but further details remain unknown. The undiscovered mechanisms of EVALI are a barrier to identifying biomarkers and developing therapeutics. Furthermore, adverse effects of e-cigarette use have been linked to chronic lung diseases and systemic effects on multiple organs. In this comprehensive review, we discuss the diverse spectrum of vaping exposures, epidemiological and clinical reports, and experimental findings to provide a better understanding of EVALI and the adverse health effects of chronic e-cigarette exposure.
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Sistemas Eletrônicos de Liberação de Nicotina , Lesão Pulmonar , Pneumonia , Vaping , Adolescente , Biomarcadores , Humanos , Lesão Pulmonar/induzido quimicamente , Lesão Pulmonar/epidemiologia , Pneumonia/etiologia , Vaping/efeitos adversos , Vaping/epidemiologia , Adulto JovemRESUMO
BACKGROUND: Dietary acculturation, or adoption of dominant culture diet by migrant groups, influences human health. We aimed to examine dietary acculturation and its relationships with cardiovascular disease (CVD), gut microbiota, and blood metabolites among US Hispanic and Latino adults. METHODS: In the HCHS/SOL (Hispanic Community Health Study/Study of Latinos), US exposure was defined by years in the United States (50 states and Washington, DC) and US nativity. A dietary acculturation pattern was derived from 14 172 participants with two 24-hour dietary recalls at baseline (2008-2011) using least absolute shrinkage and selection operator regression, with food groups as predictors of US exposure. We evaluated associations of dietary acculturation with incident CVD across ≈7 years of follow-up (n=211/14 172 cases/total) and gut microbiota (n=2349; visit 2, 2014 to 2017). Serum metabolites associated with both dietary acculturation-related gut microbiota (n=694) and incident CVD (n=108/5256 cases/total) were used as proxy measures to assess the association of diet-related gut microbiome with incident CVD. RESULTS: We identified an empirical US-oriented dietary acculturation score that increased with US exposure. Higher dietary acculturation score was associated with higher risk of incident CVD (hazard ratio per SD, 1.33 [95% CI, 1.13-1.57]), adjusted for sociodemographic, lifestyle, and clinical factors. Sixty-nine microbial species (17 enriched from diverse species, 52 depleted mainly from fiber-utilizing Clostridia and Prevotella species) were associated with dietary acculturation, driven by lower intakes of whole grains, beans, and fruits and higher intakes of refined grains. Twenty-five metabolites, involved predominantly in fatty acid and glycerophospholipid metabolism (eg, branched-chain 14:0 dicarboxylic acid** and glycerophosphoethanolamine), were associated with both diet acculturation-related gut microbiota and incident CVD. Proxy association analysis based on these metabolites suggested a positive relationship between diet acculturation-related microbiome and risk of CVD (r=0.70, P<0.001). CONCLUSIONS: Among US Hispanic and Latino adults, greater dietary acculturation was associated with elevated CVD risk, possibly through alterations in gut microbiota and related metabolites. Diet and microbiota-targeted interventions may offer opportunities to mitigate CVD burdens of dietary acculturation.
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Aculturação , Doenças Cardiovasculares , Dieta , Microbioma Gastrointestinal , Hispânico ou Latino , Humanos , Masculino , Feminino , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/etnologia , Pessoa de Meia-Idade , Estados Unidos/epidemiologia , Adulto , Dieta/efeitos adversos , Fatores de Risco , IncidênciaRESUMO
BACKGROUND: Racism is highly prevalent in the United States. Few data exist about whether perceived interpersonal racism is associated with risk of coronary heart disease (CHD). METHODS: We followed 48 305 participants in the Black Women's Health Study through biennial mailed and Internet-based health questionnaires from 1997, when they provided information on perceived interpersonal racism and were free of cardiovascular disease and cancer, until the end of 2019. We averaged participant responses to 5 validated questions about perceived interpersonal racism in everyday activities, such as "people act as if they think you are dishonest." We summed the positive responses to 3 questions about perceived racism in interactions that involved jobs, housing, and police; scores ranged from 0 (no to all) to 3 (yes to all). CHD cases were defined as nonfatal myocardial infarctions confirmed through medical records, fatal cases identified through the National Death Index, and self-reported revascularization events. We used Cox proportional hazard models adjusting for major confounders to estimate hazard ratios (HRs). RESULTS: During 22 years of follow-up, we identified 1947 incident CHD cases. For women who reported experiences of racism in employment, housing, or involving the police relative to women who reported no such experiences, the age-adjusted HR for CHD was 1.35 (95% CI, 1.13-1.61; Ptrend=0.006), and the multivariable HR for CHD was 1.26 (95% CI, 1.05-1.51; Ptrend=0.05). For women in the highest quartile of perceived interpersonal racism in daily life relative to women in the lowest quartile, the age-adjusted HR for CHD was 1.25 (95% CI, 1.07-1.46; Ptrend=0.006). After multivariable adjustment, the HR was attenuated and no longer statistically significant. CONCLUSIONS: Perceived experiences of interpersonal racism in employment, in housing, and with the police were associated with higher incidence of CHD among Black women, whereas perceived racism in everyday life was not associated with higher risk.
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Doença das Coronárias , Infarto do Miocárdio , Racismo , Humanos , Feminino , Estados Unidos/epidemiologia , Doença das Coronárias/epidemiologia , População Negra , Saúde da Mulher , Infarto do Miocárdio/epidemiologia , Incidência , Fatores de Risco , Negro ou Afro-AmericanoRESUMO
Animals possess conserved mechanisms to detect pathogens and to improve survival in their presence by altering their own behavior and physiology. Here, we utilize Caenorhabditis elegans as a model host to ask whether bacterial volatiles constitute microbe-associated molecular patterns. Using gas chromatography-mass spectrometry, we identify six prominent volatiles released by the bacterium Pseudomonas aeruginosa. We show that a specific volatile, 1-undecene, activates nematode odor sensory neurons inducing both flight and fight responses in worms. Using behavioral assays, we show that worms are repelled by 1-undecene and that this aversion response is driven by the detection of this volatile through AWB odor sensory neurons. Furthermore, we find that 1-undecene odor can induce immune effectors specific to P. aeruginosa via AWB neurons and that brief pre-exposure of worms to the odor enhances their survival upon subsequent bacterial infection. These results show that 1-undecene derived from P. aeruginosa serves as a pathogen-associated molecular pattern for the induction of protective responses in C. elegans.
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Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/fisiologia , Pseudomonas aeruginosa/metabolismo , Animais , Interações Hospedeiro-Patógeno/fisiologia , Odorantes , Células Receptoras Sensoriais/metabolismo , Células Receptoras Sensoriais/fisiologia , Transdução de Sinais/fisiologiaAssuntos
Ginecologia , Infecções por Papillomavirus , Neoplasias do Colo do Útero , Feminino , Humanos , Estados Unidos/epidemiologia , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/prevenção & controle , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/prevenção & controle , Detecção Precoce de Câncer , Programas de RastreamentoRESUMO
Receptor usage defines cell tropism and contributes to cell entry and infection. Coxsackievirus B (CVB) engages coxsackievirus and adenovirus receptor (CAR), and selectively utilizes the decay-accelerating factor (DAF; CD55) to infect cells. However, the differential receptor usage mechanism for CVB remains elusive. This study identified VP3-234 residues (234Q/N/V/D/E) as critical population selection determinants during CVB3 virus evolution, contributing to diverse binding affinities to CD55. Cryoelectron microscopy (cryo-EM) structures of CD55-binding/nonbinding isolates and their complexes with CD55 or CAR were obtained under both neutral and acidic conditions, and the molecular mechanism of VP3-234 residues determining CD55 affinity/specificity for naturally occurring CVB3 strains was elucidated. Structural and biochemical studies in vitro revealed the dynamic entry process of CVB3 and the function of the uncoating receptor CAR with different pH preferences. This work provides detailed insight into the molecular mechanism of CVB infection and contributes to an in-depth understanding of enterovirus attachment receptor usage.
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Antígenos CD55/metabolismo , Infecções por Coxsackievirus/metabolismo , Infecções por Coxsackievirus/virologia , Enterovirus Humano B/fisiologia , Interações Hospedeiro-Patógeno , Receptores Virais/metabolismo , Sequência de Aminoácidos , Substituição de Aminoácidos , Sítios de Ligação , Enterovirus Humano B/ultraestrutura , Humanos , Modelos Moleculares , Ligação Proteica , Conformação Proteica , Domínios e Motivos de Interação entre Proteínas , Receptores Virais/química , Relação Estrutura-Atividade , Ligação ViralRESUMO
The L-type calcium currents conducted by the cardiac CaV1.2 calcium channel initiate excitation-contraction coupling and serve as a key regulator of heart rate, rhythm, and force of contraction. CaV1.2 is regulated by ß-adrenergic/protein kinase A (PKA)-mediated protein phosphorylation, proteolytic processing, and autoinhibition by its carboxyl-terminal domain (CT). The small guanosine triphosphatase (GTPase) RAD (Ras associated with diabetes) has emerged as a potent inhibitor of CaV1.2, and accumulating evidence suggests a key role for RAD in mediating ß-adrenergic/PKA upregulation of channel activity. However, the relative roles of direct phosphorylation of CaV1.2 channels and phosphorylation of RAD in channel regulation remain uncertain. Here, we investigated the hypothesis that these two mechanisms converge to regulate CaV1.2 channels. Both RAD and the proteolytically processed distal CT (dCT) strongly reduced CaV1.2 activity. PKA phosphorylation of RAD and phosphorylation of Ser-1700 in the proximal CT (pCT) synergistically reversed this inhibition and increased CaV1.2 currents. Our findings reveal that the proteolytically processed form of CaV1.2 undergoes convergent regulation by direct phosphorylation of the CT and by phosphorylation of RAD. These parallel regulatory pathways provide a flexible mechanism for upregulation of the activity of CaV1.2 channels in the fight-or-flight response.
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Canais de Cálcio Tipo L , Proteínas Monoméricas de Ligação ao GTP , Adrenérgicos , Cálcio/metabolismo , Canais de Cálcio Tipo L/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/genética , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Guanosina/metabolismo , Proteínas Monoméricas de Ligação ao GTP/metabolismo , FosforilaçãoRESUMO
Natural killer (NK) cells have become a powerful candidate for adoptive tumor immunotherapy, while their therapeutic efficacy in solid tumors remains unsatisfactory. Here, we developed a hybrid module with an injectable hydrogel and hydroxyapatite (HAp) nanobelts for the controlled delivery of NK cells to enhance the therapy of solid tumors. Surface-functionalized HAp nanobelts modified with agonistic antibodies against NKG2D and 4-1BB and cytokines IL-2 and IL-21 support survival and dynamic activation. Thus, the HAp-modified chitosan (CS) thermos-sensitive hydrogel not only improved the retention of NK cells for more than 20 days in vivo but also increased NK cell function by more than one-fold. The unique architecture of this biomaterial complex protects NK cells from the hostile tumor environment and improves antitumor efficacy. The generation of a transient inflammatory niche for NK cells through a biocompatible hydrogel reservoir may be a conversion pathway to prevent cancer recurrence of resectable tumors.
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Hidrogéis , Células Matadoras Naturais , Células Matadoras Naturais/imunologia , Animais , Camundongos , Hidrogéis/química , Humanos , Neoplasias/terapia , Neoplasias/imunologia , Imunoterapia/métodos , Durapatita/química , Linhagem Celular Tumoral , Quitosana/química , Subfamília K de Receptores Semelhantes a Lectina de Células NK , Interleucinas/imunologia , Interleucina-2/imunologiaRESUMO
BACKGROUND: Understanding the etiology of recurrent tuberculosis (rTB) is important for effective TB control. Prior to the advent of whole genome sequencing (WGS), attributing rTB to relapse or reinfection using genetic information was complicated by the limited resolution of conventional genotyping methods. METHODS: We applied a systematic method of evaluating whole genome single nucleotide polymorphism (wgSNP) distances and results of phylogenetic analyses to characterize the etiology of rTB in American Indian and Alaska Native (AIAN) persons in Alaska during 2008-2020. We contextualized our findings through descriptive analyses of surveillance data and results of a literature search for investigations that characterized rTB etiology using WGS. RESULTS: The percentage of TB cases in AIAN persons in Alaska classified as recurrent episodes (11.8%) was three times the national percentage (3.9%). Of 38 recurrent episodes included in genetic analyses, we attributed 25 (65.8%) to reinfection based on wgSNP distances and phylogenetic analyses; this proportion was the highest among 16 published point estimates identified through the literature search. By comparison, we attributed 11 of 38 (28.9%) and 6 of 38 (15.8%) recurrent episodes to reinfection based on wgSNP distances alone and on conventional genotyping methods, respectively. CONCLUSIONS: WGS and attribution criteria involving genetic distances and patterns of relatedness can provide an effective means of elucidating rTB etiology. Our findings indicate that rTB occurs at high proportions among AIAN persons in Alaska and is frequently attributable to reinfection, reinforcing the importance of active surveillance and control measures to limit the spread of TB disease in Alaskan AIAN communities.
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Cilia play a key role in the regulation of signaling pathways required for embryonic development, including the proper formation of the neural tube, the precursor to the brain and spinal cord. Forward genetic screens were used to generate mouse lines that display neural tube defects (NTD) and secondary phenotypes useful in interrogating function. We describe here the L3P mutant line that displays phenotypes of disrupted Sonic hedgehog signaling and affects the initiation of cilia formation. A point mutation was mapped in the L3P line to the gene Rsg1, which encodes a GTPase-like protein. The mutation lies within the GTP-binding pocket and disrupts the highly conserved G1 domain. The mutant protein and other centrosomal and IFT proteins still localize appropriately to the basal body of cilia, suggesting that RSG1 GTPase activity is not required for basal body maturation but is needed for a downstream step in axonemal elongation.
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Cílios , Tubo Neural , Animais , Camundongos , Cílios/metabolismo , Cílios/genética , Proteínas Hedgehog/metabolismo , Proteínas Hedgehog/genética , Tubo Neural/embriologia , Tubo Neural/metabolismo , Defeitos do Tubo Neural/genética , Defeitos do Tubo Neural/metabolismo , Mutação Puntual , Transdução de SinaisRESUMO
BACKGROUND: Technological advances have enabled the generation of unique and complementary types of data or views (e.g. genomics, proteomics, metabolomics) and opened up a new era in multiview learning research with the potential to lead to new biomedical discoveries. RESULTS: We propose iDeepViewLearn (Interpretable Deep Learning Method for Multiview Learning) to learn nonlinear relationships in data from multiple views while achieving feature selection. iDeepViewLearn combines deep learning flexibility with the statistical benefits of data and knowledge-driven feature selection, giving interpretable results. Deep neural networks are used to learn view-independent low-dimensional embedding through an optimization problem that minimizes the difference between observed and reconstructed data, while imposing a regularization penalty on the reconstructed data. The normalized Laplacian of a graph is used to model bilateral relationships between variables in each view, therefore, encouraging selection of related variables. iDeepViewLearn is tested on simulated and three real-world data for classification, clustering, and reconstruction tasks. For the classification tasks, iDeepViewLearn had competitive classification results with state-of-the-art methods in various settings. For the clustering task, we detected molecular clusters that differed in their 10-year survival rates for breast cancer. For the reconstruction task, we were able to reconstruct handwritten images using a few pixels while achieving competitive classification accuracy. The results of our real data application and simulations with small to moderate sample sizes suggest that iDeepViewLearn may be a useful method for small-sample-size problems compared to other deep learning methods for multiview learning. CONCLUSION: iDeepViewLearn is an innovative deep learning model capable of capturing nonlinear relationships between data from multiple views while achieving feature selection. It is fully open source and is freely available at https://github.com/lasandrall/iDeepViewLearn .
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Aprendizado Profundo , Análise por Conglomerados , Genômica , Conhecimento , MetabolômicaRESUMO
The accumulation of AMPARs to synapses is a fundamental step in Long-term potentiation (LTP) of synaptic transmission, a well-established cellular correlate of learning and memory. The discovery of a sizeable and highly mobile population of extrasynaptic AMPARs - randomly scanning the synaptic surface under basal conditions - provided a conceptual framework for a simplified model: LTP can be induced by the capture, and hence accumulation, of laterally diffusing extrasynaptic AMPARs. Here, we review the evidence supporting a rate-limiting role of AMPAR lateral diffusion in LTP and as consequence, in learning and memory. We propose that there are "multiple solutions" for achieving the diffusional trapping of AMPAR during LTP, mainly mediated by the interaction between interchangeable AMPAR auxiliary subunits and cell-adhesion molecules containing PDZ-binding domains and synaptic scaffolds containing PDZ-domains. We believe that this molecular degeneracy in the diffusional trapping of AMPAR during LTP serve to ensure the robustness of this crucial step in the making of memories. All in all, the role of AMPAR lateral diffusion in LTP is not only a conceptual leap in our understanding of memory, but it might also hold the keys for the development of therapeutics against disorders associated with memory deficits such as Alzheimer's disease.
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Potenciação de Longa Duração , Receptores de AMPA , Difusão , Receptores de AMPA/metabolismo , Sinapses/metabolismo , Transmissão SinápticaRESUMO
l-2-Hydroxyglutarate (l-2-HG) has been regarded as a tumor metabolite, and it plays a crucial role in adaptation of tumor cells to hypoxic conditions. However, the role of l-2-HG in tumor radioresistance and the underlying mechanism have not yet been revealed. Here, we found that l-2-HG exhibited to have radioresistance effect on U87 human glioblastoma cells, which could reduce DNA damage and apoptosis caused by irradiation, promote cell proliferation and migration, and impair G2/M phase arrest. Mechanistically, l-2-HG upregulated the protein level of hypoxia-inducible factor-1α (HIF-1α) and the expression levels of HIF-1α downstream target genes. The knockdown of l-2-hydroxyglutarate dehydrogenase (L2HGDH) gene promoted the tumor growth and proliferation of U87 cells in nude mice by increasing HIF-1α expression level in vivo. In addition, the low expression level of L2HGDH gene was correlated with the short survival of patients with glioma or kidney cancer. In conclusion, our study revealed the role and mechanism of l-2-HG in tumor radioresistance and may provide a new perspective for overcoming tumor radioresistance and broaden our comprehension of the role of metabolites in tumor microenvironment.
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Skin healing occurs through an intricate process called wound healing which comprises four phases: coagulation and hemostasis, inflammation, cellular proliferation, and remodeling. Chronic wounds often arise because of prolonged or excessive inflammation, which hinders the healing process and wound closure. Despite the recognized efficacy of Pogostemon cablin (patchouli) in wound healing, the precise mechanism of action of Pogostemon cablin extract (PCE) on inflammation and wound healing remains poorly understood. In this study, we investigated the effects of PCE on cell proliferation and wound healing, as well as its anti-inflammatory activity, using in vitro experiments. We found that PCE increased cell proliferation and expression of the cell proliferation marker Ki67 and accelerated wound healing in human keratinocytes through the activation of OR2AT4. Furthermore, PCE exhibited anti-inflammatory effects by decreasing the levels of pro-inflammatory cytokines interleukin-6 and -8 in lipopolysaccharide-treated and TNF-α-exposed THP-1 and HaCaT cells, respectively. Overall, these findings suggest that PCE holds therapeutic potential by promoting cell proliferation, facilitating wound healing, and exerting anti-inflammatory effects.
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BACKGROUND: Environmental toxicants may impact survival in children with cancer, but the literature investigating these associations remains limited. Because oil and gas developments emit several hazardous air pollutants, the authors evaluated the relationship between residential proximity to oil or gas development and survival across 21 different pediatric cancers. METHODS: The Texas Cancer Registry had 29,730 children (≤19 years old) diagnosed with a primary cancer between 1995 to 2017. Geocoded data were available for 285,266 active oil or gas wells and 109,965 horizontal wells. The authors calculated whether each case lived within 1000 m (yes/no) from each type of oil or gas development. Survival analyses were conducted using Cox regression, adjusting for potential confounders. RESULTS: A total of 14.2% of cases lived within 1000 m of an oil or gas well or horizontal well. Living within 1000 m of an oil or gas well was associated with risk of mortality in cases with acute myeloid leukemia (AML) (adjusted hazard ratio [aHR], 1.36; 95% confidence interval [CI], 1.01-1.84) and hepatoblastoma (aHR, 2.13; 95% CI, 1.03-4.39). An inverse association was observed with Ewing sarcoma (aHR, 0.35; 95% CI, 0.13-0.95). No associations were observed with horizontal well. There was evidence of a dose-response effect in children with AML or hepatoblastoma and residential proximity to oil or gas wells. In general, the magnitude of association increased with decreasing distance and with higher number of wells across the three distances. CONCLUSIONS: Residential proximity to oil or gas wells at diagnosis is associated with the risk of mortality in children with AML or hepatoblastoma.