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1.
Nucleic Acids Res ; 2024 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-39460617

RESUMO

The UCSC Genome Browser (https://genome.ucsc.edu) is a widely utilized web-based tool for visualization and analysis of genomic data, encompassing over 4000 assemblies from diverse organisms. Since its release in 2001, it has become an essential resource for genomics and bioinformatics research. Annotation data available on Genome Browser includes both internally created and maintained tracks as well as custom tracks and track hubs provided by the research community. This last year's updates include over 25 new annotation tracks such as the gnomAD 4.1 track on the human GRCh38/hg38 assembly, the addition of three new public hubs, and significant expansions to the Genome Archive[GenArk) system for interacting with the enormous variety of assemblies. We have also made improvements to our interface, including updates to the browser graphic page, such as a new popup dialog feature that now displays item details without requiring navigation away from the main Genome Browser page. GenePred tracks have been upgraded with right-click options for zooming and precise navigation, along with enhanced mouseOver functions. Additional improvements include a new grouping feature for track hubs and hub description info links. A new tutorial focusing on Clinical Genetics has also been added to the UCSC Genome Browser.

2.
Nucleic Acids Res ; 52(D1): D1082-D1088, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37953330

RESUMO

The UCSC Genome Browser (https://genome.ucsc.edu) is a web-based genomic visualization and analysis tool that serves data to over 7,000 distinct users per day worldwide. It provides annotation data on thousands of genome assemblies, ranging from human to SARS-CoV2. This year, we have introduced new data from the Human Pangenome Reference Consortium and on viral genomes including SARS-CoV2. We have added 1,200 new genomes to our GenArk genome system, increasing the overall diversity of our genomic representation. We have added support for nine new user-contributed track hubs to our public hub system. Additionally, we have released 29 new tracks on the human genome and 11 new tracks on the mouse genome. Collectively, these new features expand both the breadth and depth of the genomic knowledge that we share publicly with users worldwide.


Assuntos
Bases de Dados Genéticas , Genômica , RNA Viral , Animais , Humanos , Camundongos , Genoma Humano , Genoma Viral , Internet , Anotação de Sequência Molecular , Software
3.
Nucleic Acids Res ; 51(D1): D1188-D1195, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36420891

RESUMO

The UCSC Genome Browser (https://genome.ucsc.edu) is an omics data consolidator, graphical viewer, and general bioinformatics resource that continues to serve the community as it enters its 23rd year. This year has seen an emphasis in clinical data, with new tracks and an expanded Recommended Track Sets feature on hg38 as well as the addition of a single cell track group. SARS-CoV-2 continues to remain a focus, with regular annotation updates to the browser and continued curation of our phylogenetic sequence placing tool, hgPhyloPlace, whose tree has now reached over 12M sequences. Our GenArk resource has also grown, offering over 2500 hubs and a system for users to request any absent assemblies. We have expanded our bigBarChart display type and created new ways to visualize data via bigRmsk and dynseq display. Displaying custom annotations is now easier due to our chromAlias system which eliminates the requirement for renaming sequence names to the UCSC standard. Users involved in data generation may also be interested in our new tools and trackDb settings which facilitate the creation and display of their custom annotations.


Assuntos
Bases de Dados Genéticas , Genômica , Humanos , COVID-19/epidemiologia , COVID-19/genética , Genômica/métodos , Internet , Filogenia , SARS-CoV-2/genética , Software , Navegador
4.
Nucleic Acids Res ; 50(D1): D1115-D1122, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34718705

RESUMO

The UCSC Genome Browser, https://genome.ucsc.edu, is a graphical viewer for exploring genome annotations. The website provides integrated tools for visualizing, comparing, analyzing, and sharing both publicly available and user-generated genomic datasets. Data highlights this year include a collection of easily accessible public hub assemblies on new organisms, now featuring BLAT alignment and PCR capabilities, and new and updated clinical tracks (gnomAD, DECIPHER, CADD, REVEL). We introduced a new Track Sets feature and enhanced variant displays to aid in the interpretation of clinical data. We also added a tool to rapidly place new SARS-CoV-2 genomes in a global phylogenetic tree enabling researchers to view the context of emerging mutations in our SARS-CoV-2 Genome Browser. Other new software focuses on usability features, including more informative mouseover displays and new fonts.


Assuntos
Bases de Dados Genéticas , Navegador , Animais , Genoma Humano , Humanos , Filogenia , Reação em Cadeia da Polimerase , SARS-CoV-2/genética , Interface Usuário-Computador , Sequenciamento do Exoma
5.
BMC Public Health ; 24(1): 1346, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38762449

RESUMO

BACKGROUND: According to the Physical Activity Guidelines Advisory Committee Scientific Report, limited evidence is available on sedentary behaviors (screen time) and their joint associations with physical activity (steps) for cardiovascular health in adolescence. The objective of this study was to identify joint associations of screen time and physical activity categories with cardiovascular disease (CVD) risk factors (blood pressure, hemoglobin A1c, cholesterol) in adolescence. METHODS: This study analyzed data from the Adolescent Brain Cognitive Development (ABCD) Study, comprising a diverse sample of 4,718 U.S. adolescents aged 10-15 years between 2018 and 2021. Steps were measured by a Fitbit wearable device and levels were categorized as low (1,000-6,000), medium (> 6,000-12,000), and high (> 12,000) averaged daily step counts. Self-reported recreational screen time hours per day were classified as low (0-4), medium (> 4-8), and high (> 8) hours per day. CVD risk factors including blood pressure, hemoglobin A1c, and cholesterol (total and HDL) were measured. RESULTS: The analytical sample averaged 6.6 h of screen time per day and 9,722 steps per day. In models including both screen time and steps, the high screen time category was associated with a 4.27 higher diastolic blood pressure percentile (95% CI 1.83-6.73) and lower HDL cholesterol (B= -2.85, 95% CI -4.77 to -0.94 mg/dL) compared to the low screen time category. Medium (B = 3.68, 95% CI 1.24-6.11) and low (B = 7.64, 95% CI 4.07-11.20) step categories were associated with higher diastolic blood pressure percentile compared to the high step category. The medium step category was associated with lower HDL cholesterol (B= -1.99, 95% CI -3.80 to -0.19 mg/dL) compared to the high step category. Findings were similar when screen time and step counts were analyzed as continuous variables; higher continuous step count was additionally associated with lower total cholesterol (mg/dL). CONCLUSIONS: Combinations of low screen time and high steps were generally associated with favorable cardiovascular health markers including lower diastolic blood pressure and higher HDL cholesterol, which can inform future adolescent health guidelines.


Assuntos
Doenças Cardiovasculares , Exercício Físico , Tempo de Tela , Humanos , Adolescente , Masculino , Feminino , Exercício Físico/fisiologia , Criança , Fatores de Risco de Doenças Cardíacas , Estados Unidos , Comportamento Sedentário , Fatores de Risco , Pressão Sanguínea/fisiologia , Hemoglobinas Glicadas/análise
6.
J Gen Intern Med ; 38(8): 1821-1827, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36627526

RESUMO

BACKGROUND: Previous studies have analyzed the relationship between screen time and cardiometabolic disease risk factors among adolescents, but few have examined the longitudinal effects of screen time on cardiometabolic health into adulthood using nationally representative data. OBJECTIVE: To determine prospective associations between screen time and later cardiometabolic disease over a 24-year period using a nationally representative adolescent cohort. DESIGN: Longitudinal prospective cohort data from the National Longitudinal Study of Adolescent to Adult Health (Add Health) collected from 1994 to 2018. PARTICIPANTS: Adolescents aged 11-18 years old at baseline (1994-1995) followed for 24 years. MAIN MEASURES: Predictors: screen time (five repeated measures of self-reported television and video watching from adolescence to adulthood). OUTCOMES: Five repeated measures of body mass index (BMI); two repeated measures of waist circumference, hypertension, hyperlipidemia, and diabetes collected at 15- and 24-year follow-up exams. KEY RESULTS: For the 7105 adolescents in the sample (49.7% female, 35.0% non-white), the baseline adolescent average screen time per day was 2.86 ± 0.08 hours per day, which generally declined through 24-year follow-up. Average BMI at baseline was 22.57 ± 0.13 kg/m2, which increased to 30.27 ± 0.18 kg/m2 through follow-up. By 24-year follow-up, 43.4% of participants had obesity, 8.4% had diabetes, 31.8% had hypertension, and 14.9% had hyperlipidemia. In mixed-effects generalized linear models, each additional hour of screen time per day was associated with 0.06 (95% CI 0.04-0.09) within-person increase in BMI. Each additional hour of screen time per day was associated with higher within-person odds of high waist circumference (AOR 1.17, 95% CI 1.09-1.26), obesity (AOR 1.09, 95% CI 1.03-1.15), and diabetes (AOR 1.17, 95% CI 1.07-1.28). Screen time was not significantly associated with hypertension or hyperlipidemia. CONCLUSIONS: In this prospective cohort study, higher screen time in adolescence was associated with higher odds of select indicators of cardiometabolic disease in adulthood.


Assuntos
Hipertensão , Obesidade , Adulto , Humanos , Adolescente , Feminino , Criança , Masculino , Estudos Longitudinais , Estudos Prospectivos , Obesidade/epidemiologia , Obesidade/etiologia , Índice de Massa Corporal , Hipertensão/epidemiologia , Hipertensão/complicações
7.
Nucleic Acids Res ; 49(D1): D1046-D1057, 2021 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-33221922

RESUMO

For more than two decades, the UCSC Genome Browser database (https://genome.ucsc.edu) has provided high-quality genomics data visualization and genome annotations to the research community. As the field of genomics grows and more data become available, new modes of display are required to accommodate new technologies. New features released this past year include a Hi-C heatmap display, a phased family trio display for VCF files, and various track visualization improvements. Striving to keep data up-to-date, new updates to gene annotations include GENCODE Genes, NCBI RefSeq Genes, and Ensembl Genes. New data tracks added for human and mouse genomes include the ENCODE registry of candidate cis-regulatory elements, promoters from the Eukaryotic Promoter Database, and NCBI RefSeq Select and Matched Annotation from NCBI and EMBL-EBI (MANE). Within weeks of learning about the outbreak of coronavirus, UCSC released a genome browser, with detailed annotation tracks, for the SARS-CoV-2 RNA reference assembly.


Assuntos
COVID-19/prevenção & controle , Biologia Computacional/métodos , Bases de Dados Genéticas , Genoma/genética , Genômica/métodos , SARS-CoV-2/genética , Animais , COVID-19/epidemiologia , COVID-19/virologia , Curadoria de Dados/métodos , Epidemias , Humanos , Internet , Camundongos , Anotação de Sequência Molecular/métodos , SARS-CoV-2/fisiologia , Software
8.
Hum Mutat ; 43(8): 998-1011, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35088925

RESUMO

The UCSC Genome Browser has been an important tool for genomics and clinical genetics since the sequence of the human genome was first released in 2000. As it has grown in scope to display more types of data it has also grown more complicated. The data, which are dispersed at many locations worldwide, are collected into one view on the Browser, where the graphical interface presents the data in one location. This supports the expertise of the researcher to interpret variants in the genome. Because the analysis of single nucleotide variants and copy number variants require interpretation of data at very different genomic scales, different data resources are required. We present here several Recommended Track Sets designed to facilitate the interpretation of variants in the clinic, offering quick access to datasets relevant to the appropriate scale.


Assuntos
Bases de Dados Genéticas , Software , Variações do Número de Cópias de DNA , Genoma Humano/genética , Genômica , Humanos , Internet
9.
Nucleic Acids Res ; 48(D1): D756-D761, 2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31691824

RESUMO

The University of California Santa Cruz Genome Browser website (https://genome.ucsc.edu) enters its 20th year of providing high-quality genomics data visualization and genome annotations to the research community. In the past year, we have added a new option to our web BLAT tool that allows search against all genomes, a single-cell expression viewer (https://cells.ucsc.edu), a 'lollipop' plot display mode for high-density variation data, a RESTful API for data extraction and a custom-track backup feature. New datasets include Tabula Muris single-cell expression data, GeneHancer regulatory annotations, The Cancer Genome Atlas Pan-Cancer variants, Genome Reference Consortium Patch sequences, new ENCODE transcription factor binding site peaks and clusters, the Database of Genomic Variants Gold Standard Variants, Genomenon Mastermind variants and three new multi-species alignment tracks.


Assuntos
Bases de Dados Genéticas , Genoma Humano , Software , Genômica , Humanos , Internet
10.
J Gerontol Nurs ; 48(8): 26-32, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35914079

RESUMO

Despite the rapid aging of the world's population, comprehensive assessment tools to meet the mental health needs of older adults are lacking. The aim of the current study was to assess the multidimensionality of Chinese versions of U.S.-derived instruments designed to evaluate a broad spectrum of emotional, behavioral, social, and thought problems in older adults. The Older Adult Self-Report (OASR) and Older Adult Behavior Checklist (OABCL) were completed by 686 and 639 older adults, respectively, aged 60 to 99 years, from a sample of 755 older adults. Confirmatory factor analyses (CFAs) on the 97 OASR/OABCL problem items found that the models showed good fit according to our primary and secondary fit indices. None of the seven syndromes showed informant effects, whereas four showed small sex effects, and three showed small age effects. Overall, findings demonstrate the applicability of the seven syndrome OASR/OABCL model to Chinese older adults and support the use of these instruments to assess older adult mental health in Chinese clinical and research settings. These standardized tools can help health care professionals more comprehensively assess cognitive, behavioral, and mental health problems among Chinese-speaking older adult populations. [Journal of Gerontological Nursing, 48(8), 26-32.].


Assuntos
Lista de Checagem , Saúde Mental , Idoso , China/epidemiologia , Humanos , Autorrelato , Síndrome
11.
Nucleic Acids Res ; 47(D1): D853-D858, 2019 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-30407534

RESUMO

The UCSC Genome Browser (https://genome.ucsc.edu) is a graphical viewer for exploring genome annotations. For almost two decades, the Browser has provided visualization tools for genetics and molecular biology and continues to add new data and features. This year, we added a new tool that lets users interactively arrange existing graphing tracks into new groups. Other software additions include new formats for chromosome interactions, a ChIP-Seq peak display for track hubs and improved support for HGVS. On the annotation side, we have added gnomAD, TCGA expression, RefSeq Functional elements, GTEx eQTLs, CRISPR Guides, SNPpedia and created a 30-way primate alignment on the human genome. Nine assemblies now have RefSeq-mapped gene models.


Assuntos
Bases de Dados Genéticas , Genoma/genética , Genômica , Software , Animais , Mapeamento Cromossômico , Genoma Humano/genética , Humanos , Anotação de Sequência Molecular , Navegador
12.
J Neurosci ; 39(2): 256-270, 2019 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-30361396

RESUMO

Long-range descending projections from the auditory cortex play key roles in shaping response properties in the inferior colliculus. The auditory corticocollicular projection is massive and heterogeneous, with axons emanating from cortical layers 5 and 6, and plays a key role in directing plastic changes in the inferior colliculus. However, little is known about the cortical and thalamic networks within which corticocollicular neurons are embedded. Here, laser scanning photostimulation glutamate uncaging and photoactivation of channelrhodopsin-2 were used to probe the local and long-range network differences between preidentified layer 5 and layer 6 auditory corticocollicular neurons from male and female mice in vitro Layer 5 corticocollicular neurons were found to vertically integrate supragranular excitatory and inhibitory input to a substantially greater degree than their layer 6 counterparts. In addition, all layer 5 corticocollicular neurons received direct and large thalamic inputs from channelrhodopsin-2-labeled thalamocortical fibers, whereas such inputs were less common in layer 6 corticocollicular neurons. Finally, a new low-calcium/synaptic blockade approach to separate direct from indirect inputs using laser photostimulation was validated. These data demonstrate that layer 5 and 6 corticocollicular neurons receive distinct sets of cortical and thalamic inputs, supporting the hypothesis that they have divergent roles in modulating the inferior colliculus. Furthermore, the direct connection between the auditory thalamus and layer 5 corticocollicular neurons reveals a novel and rapid link connecting ascending and descending pathways.SIGNIFICANCE STATEMENT Descending projections from the cortex play a critical role in shaping the response properties of sensory neurons. The projection from the auditory cortex to the inferior colliculus is a massive, yet poorly understood, pathway emanating from two distinct cortical layers. Here we show, using a range of optical techniques, that mouse auditory corticocollicular neurons from different layers are embedded into different cortical and thalamic networks. Specifically, we observed that layer 5 corticocollicular neurons integrate information across cortical lamina and receive direct thalamic input. The latter connection provides a hyperdirect link between acoustic sensation and descending control, thus demonstrating a novel mechanism for rapid "online" modulation of sensory perception.


Assuntos
Córtex Auditivo/citologia , Córtex Auditivo/fisiologia , Colículos Inferiores/citologia , Colículos Inferiores/fisiologia , Neurônios/fisiologia , Tálamo/fisiologia , Animais , Vias Auditivas , Limiar Auditivo/fisiologia , Contagem de Células , Channelrhodopsins/genética , Feminino , Corpos Geniculados/fisiologia , Lasers , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Fibras Nervosas/fisiologia , Rede Nervosa/citologia , Rede Nervosa/fisiologia , Estimulação Luminosa
13.
Nucleic Acids Res ; 46(D1): D762-D769, 2018 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-29106570

RESUMO

The UCSC Genome Browser (https://genome.ucsc.edu) provides a web interface for exploring annotated genome assemblies. The assemblies and annotation tracks are updated on an ongoing basis-12 assemblies and more than 28 tracks were added in the past year. Two recent additions are a display of CRISPR/Cas9 guide sequences and an interactive navigator for gene interactions. Other upgrades from the past year include a command-line version of the Variant Annotation Integrator, support for Human Genome Variation Society variant nomenclature input and output, and a revised highlighting tool that now supports multiple simultaneous regions and colors.


Assuntos
Bases de Dados Genéticas , Genoma , Navegador , Sistemas CRISPR-Cas , Apresentação de Dados , Redes Reguladoras de Genes , Genoma Humano , Humanos , Anotação de Sequência Molecular , Terminologia como Assunto , Interface Usuário-Computador
14.
J Neurosci ; 38(31): 6967-6982, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29954851

RESUMO

Auditory cortex is essential for mammals, including rodents, to detect temporal "shape" cues in the sound envelope but it remains unclear how different cortical fields may contribute to this ability (Lomber and Malhotra, 2008; Threlkeld et al., 2008). Previously, we found that precise spiking patterns provide a potential neural code for temporal shape cues in the sound envelope in the primary auditory (A1), and ventral auditory field (VAF) and caudal suprarhinal auditory field (cSRAF) of the rat (Lee et al., 2016). Here, we extend these findings and characterize the time course of the temporally precise output of auditory cortical neurons in male rats. A pairwise sound discrimination index and a Naive Bayesian classifier are used to determine how these spiking patterns could provide brain signals for behavioral discrimination and classification of sounds. We find response durations and optimal time constants for discriminating sound envelope shape increase in rank order with: A1 < VAF < cSRAF. Accordingly, sustained spiking is more prominent and results in more robust sound discrimination in non-primary cortex versus A1. Spike-timing patterns classify 10 different sound envelope shape sequences and there is a twofold increase in maximal performance when pooling output across the neuron population indicating a robust distributed neural code in all three cortical fields. Together, these results support the idea that temporally precise spiking patterns from primary and non-primary auditory cortical fields provide the necessary signals for animals to discriminate and classify a large range of temporal shapes in the sound envelope.SIGNIFICANCE STATEMENT Functional hierarchies in the visual cortices support the concept that classification of visual objects requires successive cortical stages of processing including a progressive increase in classical receptive field size. The present study is significant as it supports the idea that a similar progression exists in auditory cortices in the time domain. We demonstrate for the first time that three cortices provide temporal spiking patterns for robust temporal envelope shape discrimination but only the ventral non-primary cortices do so on long time scales. This study raises the possibility that primary and non-primary cortices provide unique temporal spiking patterns and time scales for perception of sound envelope shape.


Assuntos
Córtex Auditivo/fisiologia , Percepção Auditiva/fisiologia , Percepção do Tempo/fisiologia , Estimulação Acústica , Potenciais de Ação , Animais , Córtex Auditivo/ultraestrutura , Discriminação Psicológica , Camundongos , Modelos Neurológicos , Técnicas de Patch-Clamp , Ratos , Ratos Endogâmicos BN
15.
Nucleic Acids Res ; 45(D1): D626-D634, 2017 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-27899642

RESUMO

Since its 2001 debut, the University of California, Santa Cruz (UCSC) Genome Browser (http://genome.ucsc.edu/) team has provided continuous support to the international genomics and biomedical communities through a web-based, open source platform designed for the fast, scalable display of sequence alignments and annotations landscaped against a vast collection of quality reference genome assemblies. The browser's publicly accessible databases are the backbone of a rich, integrated bioinformatics tool suite that includes a graphical interface for data queries and downloads, alignment programs, command-line utilities and more. This year's highlights include newly designed home and gateway pages; a new 'multi-region' track display configuration for exon-only, gene-only and custom regions visualization; new genome browsers for three species (brown kiwi, crab-eating macaque and Malayan flying lemur); eight updated genome assemblies; extended support for new data types such as CRAM, RNA-seq expression data and long-range chromatin interaction pairs; and the unveiling of a new supported mirror site in Japan.


Assuntos
Bases de Dados Genéticas , Ferramenta de Busca , Navegador , Animais , Biologia Computacional/métodos , Genoma , Genômica/métodos , Humanos , Anotação de Sequência Molecular , Software
16.
Plant Cell ; 26(6): 2601-2616, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24963054

RESUMO

In higher plants, cellulose is synthesized by plasma membrane-localized cellulose synthase complexes (CSCs). Arabidopsis thaliana GH9A1/KORRIGAN1 is a membrane-bound, family 9 glycosyl hydrolase that is important for cellulose synthesis in both primary and secondary cell walls. Most previously identified korrigan1 mutants show severe phenotypes such as embryo lethality; therefore, the role of GH9A1 in cellulose synthesis remains unclear. Here, we report a novel A577V missense mutation, designated jiaoyao1 (jia1), in the second of the glycosyl hydrolase family 9 active site signature motifs in GH9A1. jia1 is defective in cell expansion in dark-grown hypocotyls, roots, and adult plants. Consistent with its defect in cell expansion, this mutation in GH9A1 resulted in reduced cellulose content and reduced CSC velocity at the plasma membrane. Green fluorescent protein-GH9A1 is associated with CSCs at multiple locations, including the plasma membrane, Golgi, trans-Golgi network, and small CESA-containing compartments or microtubule-associated cellulose synthase compartments, indicating a tight association between GH9A1 and CSCs. GH9A1A577V abolishes the endoglucanase activity of GH9A1 in vitro but does not affect its interaction with CESAs in vitro, suggesting that endoglucanase activity is important for cellulose synthesis. Interestingly, jia1 results in both cellulose microfibril and microtubule disorganization. Our study establishes the important role of endoglucanase in cellulose synthesis and cellulose microfibril organization in plants.

17.
J Neurophysiol ; 115(4): 1886-904, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26843599

RESUMO

Mammals perceive a wide range of temporal cues in natural sounds, and the auditory cortex is essential for their detection and discrimination. The rat primary (A1), ventral (VAF), and caudal suprarhinal (cSRAF) auditory cortical fields have separate thalamocortical pathways that may support unique temporal cue sensitivities. To explore this, we record responses of single neurons in the three fields to variations in envelope shape and modulation frequency of periodic noise sequences. Spike rate, relative synchrony, and first-spike latency metrics have previously been used to quantify neural sensitivities to temporal sound cues; however, such metrics do not measure absolute spike timing of sustained responses to sound shape. To address this, in this study we quantify two forms of spike-timing precision, jitter, and reliability. In all three fields, we find that jitter decreases logarithmically with increase in the basis spline (B-spline) cutoff frequency used to shape the sound envelope. In contrast, reliability decreases logarithmically with increase in sound envelope modulation frequency. In A1, jitter and reliability vary independently, whereas in ventral cortical fields, jitter and reliability covary. Jitter time scales increase (A1 < VAF < cSRAF) and modulation frequency upper cutoffs decrease (A1 > VAF > cSRAF) with ventral progression from A1. These results suggest a transition from independent encoding of shape and periodicity sound cues on short time scales in A1 to a joint encoding of these same cues on longer time scales in ventral nonprimary cortices.


Assuntos
Potenciais Evocados Auditivos , Neurônios/fisiologia , Periodicidade , Animais , Córtex Auditivo/citologia , Córtex Auditivo/fisiologia , Percepção Auditiva , Masculino , Ratos , Tempo de Reação , Som
18.
Int J Mol Sci ; 17(3): 400, 2016 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-26999120

RESUMO

Patients with brain metastasis from renal cell carcinoma (RCC) or melanoma have historically had very poor prognoses of less than one year. Stereotactic radiosurgery (SRS) can be an effective treatment for patients with these tumors. This study analyzes the effect of pretreatment prognostic factors on overall survival (OS) for RCC and melanoma patients with metastasis to the brain treated with SRS. A total of 122 patients with brain metastases from either RCC or melanoma were grouped by age at brain metastasis diagnosis, whether they received whole brain radiation therapy (WBRT) in addition to SRS, or they underwent surgical resection, Karnofsky Performance Score (KPS), number of brain metastases, and primary tumor. Median survival times for melanoma patients and RCC patients were 8.20 ± 3.06 and 12.70 ± 2.63 months, respectively. Patients with >5 metastases had a significantly shorter median survival time (6.60 ± 2.45 months) than the reference group (1 metastasis, 10.70 ± 13.40 months, p = 0.024). Patients with KPS ≤ 60 experienced significantly shorter survival than the reference group (KPS = 90-100), with median survival times of 5.80 ± 2.46 months (p < 0.001) and 45.20 ± 43.52 months, respectively. We found a median overall survival time of 12.7 and 8.2 months for RCC and melanoma, respectively. Our study determined that a higher number of brain metastases (>5) and lower KPS were statistically significant predictors of a lower OS prognosis.


Assuntos
Neoplasias Encefálicas/radioterapia , Carcinoma de Células Renais/radioterapia , Neoplasias Renais/radioterapia , Melanoma/radioterapia , Idoso , Neoplasias Encefálicas/secundário , Carcinoma de Células Renais/patologia , Feminino , Humanos , Neoplasias Renais/patologia , Masculino , Melanoma/patologia , Pessoa de Meia-Idade , Radiocirurgia , Análise de Sobrevida
19.
Plant Physiol ; 163(2): 907-13, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23995148

RESUMO

Sum frequency generation (SFG) vibration spectroscopy can selectively detect crystalline cellulose without spectral interference from cell wall matrix components. Here, we show that the cellulose SFG spectrum is sensitive to cellulose microfibril alignment and packing within the cell wall. SFG intensity at 2,944 cm(-1) correlated well with crystalline cellulose contents of various regions of the Arabidopsis (Arabidopsis thaliana) inflorescence, while changes in the 3,320/2,944 cm(-1) intensity ratio suggest subtle changes in cellulose ordering as tissues mature. SFG analysis of two cellulose synthase mutants (irx1/cesa8 and irx3/cesa7) indicates a reduction in cellulose content without evidence of altered cellulose structure. In primary cell walls of Arabidopsis, cellulose exhibited a characteristic SFG peak at 2,920 and 3,320 cm(-1), whereas in secondary cell walls, it had peaks at 2,944 and 3,320 cm(-1). Starch (amylose) gave an SFG peak at 2,904 cm(-1) (CH methine) whose intensity increased with light exposure prior to harvest. Selective removal of matrix polysaccharides from primary cell walls by acid hydrolysis resulted in an SFG spectrum resembling that of secondary wall cellulose. Our results show that SFG spectroscopy is sensitive to the ordering of cellulose microfibrils in plant cell walls at the meso scale (nm to µm) that is important for cell wall architecture but cannot be probed by other spectroscopic or diffraction techniques.


Assuntos
Arabidopsis/citologia , Arabidopsis/metabolismo , Parede Celular/química , Celulose/química , Análise Espectral/métodos , Glucosiltransferases/genética , Inflorescência/metabolismo , Mutação/genética , Difração de Raios X
20.
Biomacromolecules ; 15(7): 2718-24, 2014 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-24846814

RESUMO

The crystallinity, allomorph content, and mesoscale ordering of cellulose produced by Gluconacetobacter xylinus cultured with different plant cell wall matrix polysaccharides were studied with vibrational sum frequency generation (SFG) spectroscopy and X-ray diffraction (XRD). Crystallinity and ordering were assessed as the intensity of SFG signals in the CH/CH2 stretch vibration region (and confirmed by XRD), while Iα content was assessed by the relative intensity of the OH stretch vibration at 3240 cm(-1). A key finding is that the presence of xyloglucan in the culture medium greatly reduced Iα allomorph content but with a relatively small effect on cellulose crystallinity, whereas xylan resulted in a larger decrease in crystallinity with a relatively small decrease in the Iα fraction. Arabinoxylan and various pectins had much weaker effects on cellulose structure as assessed by SFG and XRD. Homogalacturonan with calcium ion reduced the SFG signal, evidently by changing the ordering of cellulose microfibrils. We propose that the distinct effects of matrix polysaccharides on cellulose crystal structure result, at least in part, from selective interactions of the backbone and side chains of matrix polysaccharides with cellulose chains during the formation of the microfibril.


Assuntos
Parede Celular/química , Celulose/química , Pectinas/química , Configuração de Carboidratos , Celulose/ultraestrutura , Cristalização , Cristalografia por Raios X , Glucanos/química , Gluconacetobacter xylinus/química , Células Vegetais/química , Vibração , Xilanos/química
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