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1.
Genome Res ; 32(2): 389-402, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34949670

RESUMO

Accurate transcription start site (TSS) annotations are essential for understanding transcriptional regulation and its role in human disease. Gene collections such as GENCODE contain annotations for tens of thousands of TSSs, but not all of these annotations are experimentally validated nor do they contain information on cell type-specific usage. Therefore, we sought to generate a collection of experimentally validated TSSs by integrating RNA Annotation and Mapping of Promoters for the Analysis of Gene Expression (RAMPAGE) data from 115 cell and tissue types, which resulted in a collection of approximately 50 thousand representative RAMPAGE peaks. These peaks are primarily proximal to GENCODE-annotated TSSs and are concordant with other transcription assays. Because RAMPAGE uses paired-end reads, we were then able to connect peaks to transcripts by analyzing the genomic positions of the 3' ends of read mates. Using this paired-end information, we classified the vast majority (37 thousand) of our RAMPAGE peaks as verified TSSs, updating TSS annotations for 20% of GENCODE genes. We also found that these updated TSS annotations are supported by epigenomic and other transcriptomic data sets. To show the utility of this RAMPAGE rPeak collection, we intersected it with the NHGRI/EBI genome-wide association study (GWAS) catalog and identified new candidate GWAS genes. Overall, our work shows the importance of integrating experimental data to further refine TSS annotations and provides a valuable resource for the biological community.


Assuntos
Regulação da Expressão Gênica , Estudo de Associação Genômica Ampla , Humanos , Regiões Promotoras Genéticas , Sítio de Iniciação de Transcrição
2.
Hum Genet ; 142(8): 1091-1111, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36935423

RESUMO

Regulatory elements are the genomic regions that interact with transcription factors to control cell-type-specific gene expression in different cellular environments. A precise and complete catalog of functional elements encoded by the human genome is key to understanding mammalian gene regulation. Here, we review the current state of regulatory element annotation. We first provide an overview of assays for characterizing functional elements, including genome, epigenome, transcriptome, three-dimensional chromatin interaction, and functional validation assays. We then discuss computational methods for defining regulatory elements, including peak-calling and other statistical modeling methods. Finally, we introduce several high-quality lists of regulatory element annotations and suggest potential future directions.


Assuntos
Cromatina , Sequências Reguladoras de Ácido Nucleico , Animais , Humanos , Sequências Reguladoras de Ácido Nucleico/genética , Cromatina/genética , Regulação da Expressão Gênica , Genômica/métodos , Mamíferos/genética , Genoma Humano
3.
Opt Express ; 31(22): 36293-36303, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-38017784

RESUMO

We have theoretically investigated the size-dependent optoelectronic properties of InGaP/AlGaInP-based red micro-LEDs through an electro-optical-thermal coupling model. The model considers thermal effects due to current crowding near the electrodes, non-thermal efficiency droop due to electron leakage, and etch defects on the LED sidewall. Sidewall defects reduce the carrier concentration at the light-emitting surface's edge and exacerbate the current crowding effect. In addition, p-side electron leakage at high current densities is the leading cause of the efficiency droop of AlGaInP LEDs. In contrast, the effect of temperature on the overall efficiency degradation of LEDs is even more significant.

4.
Nucleic Acids Res ; 49(10): 5705-5725, 2021 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-33978759

RESUMO

Gene expression is controlled by regulatory elements within accessible chromatin. Although most regulatory elements are cell type-specific, a subset is accessible in nearly all the 517 human and 94 mouse cell and tissue types assayed by the ENCODE consortium. We systematically analyzed 9000 human and 8000 mouse ubiquitously-accessible candidate cis-regulatory elements (cCREs) with promoter-like signatures (PLSs) from ENCODE, which we denote ubi-PLSs. These are more CpG-rich than non-ubi-PLSs and correspond to genes with ubiquitously high transcription, including a majority of cell-essential genes. ubi-PLSs are enriched with motifs of ubiquitously-expressed transcription factors and preferentially bound by transcriptional cofactors regulating ubiquitously-expressed genes. They are highly conserved between human and mouse at the synteny level but exhibit frequent turnover of motif sites; accordingly, ubi-PLSs show increased variation at their centers compared with flanking regions among the ∼186 thousand human genomes sequenced by the TOPMed project. Finally, ubi-PLSs are enriched in genes implicated in Mendelian diseases, especially diseases broadly impacting most cell types, such as deficiencies in mitochondrial functions. Thus, a set of roughly 9000 mammalian promoters are actively maintained in an accessible state across cell types by a distinct set of transcription factors and cofactors to ensure the transcriptional programs of cell-essential genes.


Assuntos
Cromatina/metabolismo , Epigênese Genética , Regulação da Expressão Gênica/genética , Sequências Reguladoras de Ácido Nucleico , Fatores de Transcrição/metabolismo , Transcriptoma/genética , Motivos de Aminoácidos , Animais , Composição de Bases , Cromatina/genética , Metilação de DNA , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Bases de Dados Genéticas , Epigenômica , Ontologia Genética , Genes Essenciais , Componentes Genômicos , Genoma Humano , Humanos , Camundongos , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Especificidade de Órgãos/genética , Regiões Promotoras Genéticas , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , TATA Box , Fatores de Transcrição/genética
5.
Environ Sci Technol ; 56(9): 5960-5972, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35416037

RESUMO

Increasing global deoxygenation has widely formed oxygen-limited biotopes, altering the metabolic pathways of numerous microbes and causing a large greenhouse effect of nitrous oxide (N2O). Although there are many sources of N2O, denitrification is the sole sink that removes N2O from the biosphere, and the low-level oxygen in waters has been classically thought to be the key factor regulating N2O emissions from incomplete denitrification. However, through microcosm incubations with sandy sediment, we demonstrate here for the first time that the stress from oxygenated environments does not suppress, but rather boosts the complete denitrification process when the sulfur cycle is actively ongoing. This study highlights the potential of reducing N2O-driven greenhouse warming and fills a gap in pre-cognitions on the nitrogen cycle, which may impact our current understanding of greenhouse gas sinks. Combining molecular techniques and kinetic verification, we reveal that dominant inhibitions in oxygen-limited environments can interestingly undergo triple detoxification by cryptic sulfur and oxygen cycling, which may extensively occur in nature but have been long neglected by researchers. Furthermore, reviewing the present data and observations from natural and artificial ecosystems leads to the necessary revision needs of the global nitrogen cycle.


Assuntos
Desnitrificação , Oxigênio , Ecossistema , Ciclo do Nitrogênio , Enxofre
6.
Environ Res ; 213: 113674, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35700768

RESUMO

Pseudomonas sp. C27 can achieve the conversion of toxic sulfide to economical elemental sulfur (S0) with various electron acceptors. In this study the distribution pattern of S0 produced by C27 in denitrifying sulfide removal (DSR) process was explored. The SEM observation identified that the particle size of the biogenic S0 was at micron level. Strikingly, a novel distribution pattern of S0 was revealed that the produced S0 was not directly secreted extracellularly, but be stored temporarily in the cell interior. Pyrolysis at 65 °C for 20 min were recommended prior to S0 recovery, which could maximize the separation of extracellular polymeric substances (EPS) from C27. Furthermore, the effects of N/S molar ratio, initial sulfide concentration, and micro-oxygen condition were investigated to improve the production of S0 by C27. The highest S0 production was obtained at S/N of 3 and anaerobic condition seemed to favor the S0 production by C27. This study would provide a theoretical support for highly efficient sulfide removal as well as S0 recovery in sulfide-laden wastewater treatment.


Assuntos
Pseudomonas , Purificação da Água , Reatores Biológicos , Desnitrificação , Nitratos , Sulfetos , Enxofre
7.
Opt Express ; 29(13): 20217-20228, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34266115

RESUMO

In this article, 2000 PPI red silicon-based AlGaInP micro-LED arrays were fabricated and investigated. The AlGaInP epilayer was transferred onto the silicon substrate via the In-Ag bonding technique and an epilayer lift-off process. The silicon substrate with a high thermal conductivity could provide satisfactory heat dissipation, leading to micro-LED arrays that had a stable emission spectrum with increasing current density from 20 to 420 A/cm2 along with a red-shift of the peak position from 624.69 to 627.12 nm (Δλ = 2.43 nm). Additionally, increasing the injection current density had little effect on the CIE (x, y) of the micro-LED arrays. Further, the I-V characteristics and light output power of micro-LED arrays with different pixel sizes demonstrated that the AlGaInP red micro-LED array on a silicon substrate had excellent electrical stability and optical output.

8.
Nutr Metab Cardiovasc Dis ; 31(9): 2700-2706, 2021 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-34218986

RESUMO

BACKGROUND AND AIMS: Gender-specific differences were found in serum uric acid (SUA) levels and the risk of isolated distal deep vein thrombosis (IDDVT). This study aimed to explore the association among gender, SUA, and IDDVT in stroke patients. METHODS AND RESULTS: Finally, 3404 patients were recruited and divided into two groups: IDDVT (n = 1233) and Non-IDDVT (n = 2171) groups. Propensity score matching (PSM) was conducted to match the patients. Binary logistic regression was adopted to explore the association between SUA and IDDVT, with the SUA divided into quartiles. After PSM, 975 patients were included in each group. Non-IDDVT group had a larger proportion of male than IDDVT group (64.9% vs. 52.7%, p < 0.001). Moreover, males showed higher SUA levels than females (316.7 ± 102.1 vs. 261.8 ± 94.0 µmol/L, t = 12.1, p < 0.001). The highest quartile of SUA (≥346 µmol/L) showed a lower risk of IDDVT (OR = 0.629, p = 0.001), while the lowest quartile (≤225 µmol/L) showed a higher risk of IDDVT (OR = 1.361, p = 0.022). CONCLUSION: In patients with stroke, SUA played a protective role in IDDVT. Females had a higher risk of IDDVT, which may be owing to the lower SUA levels than males. In clinical practice, more attention should be paid to the risk of IDDVT in females, especially those with lower SUA levels.


Assuntos
Disparidades nos Níveis de Saúde , Acidente Vascular Cerebral/sangue , Ácido Úrico/sangue , Trombose Venosa/sangue , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Proteção , Medição de Risco , Fatores de Risco , Fatores Sexuais , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/epidemiologia , Trombose Venosa/diagnóstico por imagem , Trombose Venosa/epidemiologia
9.
Brain Behav Immun ; 88: 529-534, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32304881

RESUMO

Our previous study showed that metabolic abnormalities reduced the levels of brain-derived neurotrophic factor (BDNF) and deteriorated cognitive performance in patients with schizophrenia. Inflammation may play a key role in this process. Omega-3 fatty acids have been documented to ameliorate inflammation. Therefore, we hypothesized that omega-3 fatty acids may be of value in enhancing BDNF levels and improving cognitive function in patients with schizophrenia with metabolic syndrome (MetS). We recruited 80 patients with both schizophrenia and MetS who received long-term olanzapine monotherapy. The enzyme-linked immunosorbent assay was used to measure the plasma levels of C-reactive protein (CRP), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α). The patients were randomly assigned to the OMG-3 group (n = 40) or the placebo group (n = 40). Of the 80 patients who consented to the study, 72 completed this 12-week RCT. The primary outcome was the changes from baseline to 12 weeks in clinical characteristics and the levels of BDNF, CRP, IL-6 and TNF-α. There was a significant correlation between omega-3 fatty acid treatment and enhanced delayed memory factor in the RBANS assessment (Fgroup×time = 6.82; df = 1, 66; P = 0.01) when the patients completed this study. Along with cognitive improvement, omega-3 fatty acids enhanced BDNF (Fgroup×time = 4.93; df = 1, 66; P = 0.03) and reduced CRP (Fgroup×time = 17.11; df = 1, 66; P < 0.01), IL-6 (Fgroup×time = 9.71; df = 1, 66; P < 0.004) and TNF-α (Fgroup×time = 6.71; df = 1, 66; P = 0.012) levels after 12 weeks of treatment. The changes in BDNF levels are negatively correlated with the changes in TNF-α levels (r = -0.37, P = 0.03) but not with the changes in CRP and IL-6 levels. Our findings provide suggestive evidence that omega-3 fatty acids have beneficial effects on cognitive function in patients with MetS, which is paralleled by enhanced BDNF levels.


Assuntos
Disfunção Cognitiva , Ácidos Graxos Ômega-3/uso terapêutico , Síndrome Metabólica , Esquizofrenia , Disfunção Cognitiva/tratamento farmacológico , Humanos , Síndrome Metabólica/complicações , Síndrome Metabólica/tratamento farmacológico , Olanzapina/uso terapêutico , Esquizofrenia/complicações , Esquizofrenia/tratamento farmacológico
10.
BMC Psychiatry ; 20(1): 387, 2020 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-32723375

RESUMO

BACKGROUNDS: Major depressive disorder is an ordinary mental disorder, and suicide is considered to be a major concern among patients with MDD. Previous studies focused on the relationship between suicide attempts and metabolism in elderly patients with MDD, while ignore the young people. The aim of this study is to find the potential relationship between suicide attempts and metabolism in young patients with MDD to find a way to prevent and ultimately reduce suicide in young patients with MDD. METHODS: Cross-sectional design was employed in the study.740 patients aged between 18 and 45 years old with MDD had been consecutively recruited in this study between 2011 and 2017, 128 of whom had suicide attempts. Their serum samples used to monitor fasting blood glucose, serum lipids as well as socio-demographic characteristics were collected. Besides, some clinical scales were also employed to measure symptoms of anxiety, depression and other conditions. RESULTS: This study indicated that compared with non-suicide attempters, suicide attempters in young patients with MDD showed higher levels of FBG, TC, LDL-C (all p <  0.05) and lower levels of HDL-C(p <  0.001). Further logistic regression analysis suggested that suicide attempts were associated with increased FBG, decreased HDL-C, the course of disease, HAMD scores and obvious anxiety. CONCLUSIONS: Suicide attempts in young patients with MDD may be predicted by metabolic levels in the future. And our findings suggested that the level of FBG and HDL-C can be promising biomarkers to predict the occurrence of this event.


Assuntos
Transtorno Depressivo Maior , Preparações Farmacêuticas , Transtornos Psicóticos , Adolescente , Adulto , Idoso , Estudos Transversais , Transtorno Depressivo Maior/diagnóstico , Humanos , Pessoa de Meia-Idade , Tentativa de Suicídio , Adulto Jovem
11.
Nucleic Acids Res ; 46(21): 11184-11201, 2018 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-30137428

RESUMO

Enhancers are distal cis-regulatory elements that modulate gene expression. They are depleted of nucleosomes and enriched in specific histone modifications; thus, calling DNase-seq and histone mark ChIP-seq peaks can predict enhancers. We evaluated nine peak-calling algorithms for predicting enhancers validated by transgenic mouse assays. DNase and H3K27ac peaks were consistently more predictive than H3K4me1/2/3 and H3K9ac peaks. DFilter and Hotspot2 were the best DNase peak callers, while HOMER, MUSIC, MACS2, DFilter and F-seq were the best H3K27ac peak callers. We observed that the differential DNase or H3K27ac signals between two distant tissues increased the area under the precision-recall curve (PR-AUC) of DNase peaks by 17.5-166.7% and that of H3K27ac peaks by 7.1-22.2%. We further improved this differential signal method using multiple contrast tissues. Evaluated using a blind test, the differential H3K27ac signal method substantially improved PR-AUC from 0.48 to 0.75 for predicting heart enhancers. We further validated our approach using postnatal retina and cerebral cortex enhancers identified by massively parallel reporter assays, and observed improvements for both tissues. In summary, we compared nine peak callers and devised a superior method for predicting tissue-specific mouse developmental enhancers by reranking the called peaks.


Assuntos
Algoritmos , Cromatina/genética , Biologia Computacional/métodos , Elementos Facilitadores Genéticos/genética , Código das Histonas/genética , Animais , Sítios de Ligação , Cromatina/metabolismo , Histonas/metabolismo , Camundongos Transgênicos , Especificidade de Órgãos , Processamento de Proteína Pós-Traducional , Fatores de Transcrição/metabolismo
12.
J Proteome Res ; 16(8): 3019-3029, 2017 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-28707887

RESUMO

Spatial-temporal regulation among proteins forms dynamic networks in cells. Coexistence in common cell compartments can improve biological reliability of the protein-protein interactions. However, this is usually overlooked by most proteomic studies and leads to unrealistic discoveries. In this paper, we systematically characterize the interaction localization diversity in the human protein interactome using the localization coefficient, a novel metric proposed for assessing how diversely the interactions localize among cell compartments. Our analysis reveals the following: (1) the subcellular networks of the nucleus, cytosol, and mitochondrion are dense but the interactions tend to localize in specific cell compartments, whereas the subnetworks of the secretory-pathway, membrane, and extracellular region are sparse but the interactions are diversely localized; (2) the housekeeping proteins tend to appear in multiple compartments, while the tissue-specific proteins present a relatively flat profile of localization breadth; (3) the autophagy proteins tend to diversely localize in multiple compartments, especially those with high connectivity, compared with the apoptosis proteins; (4) the proteins targeted by small-molecule drugs show no preference for compartments, whereas the proteins directed by antibody-based drugs tend to belong to transmembrane regions with a strong diversity. In summary, our analysis provides a comprehensive view of the subcellular localization for interacting proteins, demonstrates that localization diversity is an important feature of protein interactions, and shows its ability to highlight meaningful biological functions.


Assuntos
Compartimento Celular , Mapas de Interação de Proteínas/fisiologia , Proteoma/análise , Frações Subcelulares/química , Humanos , Espaço Intracelular/química , Mapeamento de Interação de Proteínas , Proteômica/métodos , Análise Espaço-Temporal , Frações Subcelulares/fisiologia
13.
RNA ; 20(7): 989-93, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24803509

RESUMO

Transcriptomic analyses have revealed an unexpected complexity in the eukaryote transcriptome, which includes not only protein-coding transcripts but also an expanding catalog of noncoding RNAs (ncRNAs). Diverse coding and noncoding RNAs (ncRNAs) perform functions through interaction with each other in various cellular processes. In this project, we have developed RAID (http://www.rna-society.org/raid), an RNA-associated (RNA-RNA/RNA-protein) interaction database. RAID intends to provide the scientific community with all-in-one resources for efficient browsing and extraction of the RNA-associated interactions in human. This version of RAID contains more than 6100 RNA-associated interactions obtained by manually reviewing more than 2100 published papers, including 4493 RNA-RNA interactions and 1619 RNA-protein interactions. Each entry contains detailed information on an RNA-associated interaction, including RAID ID, RNA/protein symbol, RNA/protein categories, validated method, expressing tissue, literature references (Pubmed IDs), and detailed functional description. Users can query, browse, analyze, and manipulate RNA-associated (RNA-RNA/RNA-protein) interaction. RAID provides a comprehensive resource of human RNA-associated (RNA-RNA/RNA-protein) interaction network. Furthermore, this resource will help in uncovering the generic organizing principles of cellular function network.


Assuntos
Bases de Dados de Ácidos Nucleicos , Proteínas/metabolismo , RNA/metabolismo , Sítios de Ligação/genética , Previsões/métodos , Perfilação da Expressão Gênica/métodos , Redes Reguladoras de Genes , Humanos , Armazenamento e Recuperação da Informação/métodos , Ligação Proteica , Interface Usuário-Computador
14.
Phys Chem Chem Phys ; 17(19): 13129-36, 2015 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-25916946

RESUMO

A molecule or a molecular system always consists of excited states of different spin multiplicities. With conventional optical excitations, only the (bright) states with the same spin multiplicity of the ground state could be directly reached. How to reveal the dynamics of excited (dark) states remains the grand challenge in the topical fields of photochemistry, photophysics, and photobiology. For a singlet-triplet coupled molecular system, the (bright) singlet dynamics can be routinely examined by conventional femtosecond pump-probe spectroscopy. However, owing to the involvement of intrinsically fast decay channels such as intramolecular vibrational redistribution and internal conversion, it is very difficult, if not impossible, to single out the (dark) triplet dynamics. Herein, we develop a novel strategy that uses an ultrafast broadband white-light continuum as a excitation light source to enhance the probability of intersystem crossing, thus facilitating the population flow from the singlet space to the triplet space. With a set of femtosecond time-reversed pump-probe experiments, we report on a proof-of-concept molecular system (i.e., the malachite green molecule) that the pure triplet dynamics can be mapped out in real time through monitoring the modulated emission that occurs solely in the triplet space. Significant differences in excited-state dynamics between the singlet and triplet spaces have been observed. This newly developed approach may provide a useful tool for examining the elusive dark-state dynamics of molecular systems and also for exploring the mechanisms underlying molecular luminescence/photonics and solar light harvesting.


Assuntos
Escuridão , Teoria Quântica , Modelos Teóricos , Espectrometria de Fluorescência
15.
Science ; 383(6690): eabn3263, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38422184

RESUMO

Vocal production learning ("vocal learning") is a convergently evolved trait in vertebrates. To identify brain genomic elements associated with mammalian vocal learning, we integrated genomic, anatomical, and neurophysiological data from the Egyptian fruit bat (Rousettus aegyptiacus) with analyses of the genomes of 215 placental mammals. First, we identified a set of proteins evolving more slowly in vocal learners. Then, we discovered a vocal motor cortical region in the Egyptian fruit bat, an emergent vocal learner, and leveraged that knowledge to identify active cis-regulatory elements in the motor cortex of vocal learners. Machine learning methods applied to motor cortex open chromatin revealed 50 enhancers robustly associated with vocal learning whose activity tended to be lower in vocal learners. Our research implicates convergent losses of motor cortex regulatory elements in mammalian vocal learning evolution.


Assuntos
Elementos Facilitadores Genéticos , Eutérios , Evolução Molecular , Regulação da Expressão Gênica , Córtex Motor , Neurônios Motores , Proteínas , Vocalização Animal , Animais , Quirópteros/genética , Quirópteros/fisiologia , Vocalização Animal/fisiologia , Córtex Motor/citologia , Córtex Motor/fisiologia , Cromatina/metabolismo , Neurônios Motores/fisiologia , Laringe/fisiologia , Epigênese Genética , Genoma , Proteínas/genética , Proteínas/metabolismo , Sequência de Aminoácidos , Eutérios/genética , Eutérios/fisiologia , Aprendizado de Máquina
16.
J Am Chem Soc ; 135(33): 12468-74, 2013 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-23895410

RESUMO

Graphene oxide (GO) is an attractive alternative for large-scale production of graphene, but its general structure is still under debate due to its complicated nonstoichiometric nature. Here we perform a set of femtosecond pump-probe experiments on as-synthesized GO to extrapolate structural information in situ. Remarkably, it is observed that, in these highly oxidized GO samples, the ultrafast graphene-like dynamics intrinsic to pristine graphene is completely dominant over a wide energy region and can be modified by the localized impurity states and the electron-phonon coupling under certain conditions. These observations, combined with the X-ray photoelectron spectroscopy analysis and control experiments, lead to an important conclusion that GO consists of two types of domain, namely the carbon-rich graphene-like domain and the oxygen-rich domain. This study creates a new understanding of the realistic domain structure and properties of as-synthesized GO, offering useful guidance for future applications based on chemically modified/functionalized graphenes.


Assuntos
Arsênio/química , Grafite/química , Grafite/síntese química , Óxidos/química , Análise Espectral , Técnicas de Química Sintética , Oxigênio/química , Fatores de Tempo
17.
Environ Int ; 174: 107873, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36933304

RESUMO

Brominated flame retardants (BFRs) are persistent organic pollutants. Many bacteria are able to debrominate BFRs, but the underlying mechanism is unclear. Herein, we discovered that reactive sulfur species (RSS), which have strong reductive activity and are commonly present in bacteria, might be one of the reasons leading to such ability. Experiments performed with RSS (H2S and HSSH) and BFRs indicated that RSS can debrominate BFRs via two different mechanisms simultaneously: the substitutive debromination that generates thiol-BFRs and the reductive debromination that generates hydrogenated BFRs. Debromination reactions rapidly happened under neutral pH and ambient temperature, and the debromination degree was around 30% - 55% in one hour. Two Pseudomonas strains, Pseudomonas sp. C27 and Pseudomonas putida B6-2 both produced extracellular RSS and showed debromination activity. C27 debrominated HBCD, TBECH, and TBP by 5.4%, 17.7%, and 15.9% in two days. Whereas, B6-2 debrominated the three BFRs by 0.4%, 0.6%, and 0.3% in two days. The two bacteria produced different amounts and species of RSS, which were likely responsible for the contrasted degrees of the debromination. Our finding unveiled a novel, non-enzymatic debromination mechanism that many bacteria may possess. RSS producing bacteria have potentials to contribute to bioremediation of BFRs-polluted environments.


Assuntos
Retardadores de Chama , Hidrocarbonetos Bromados , Biodegradação Ambiental
18.
Antioxidants (Basel) ; 12(3)2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36979016

RESUMO

The definition of reactive sulfur species (RSS) is inspired by the reactivity and variable chemical valence of sulfur. Sulfur is an essential element for life and is a part of global geochemical cycles. Wastewater treatment bioreactors can be divided into two major categories: sulfur reduction and sulfur oxidation. We review the origins of the definition of RSS and related biotechnological processes in environmental management. Sulfate reduction, sulfide oxidation, and sulfur-based redox reactions are key to driving the coupled global carbon, nitrogen, and sulfur co-cycles. This shows the coupling of the sulfur cycle with the carbon and nitrogen cycles and provides insights into the global material-chemical cycle. We also review the biological classification and RSS metabolic mechanisms of functional microorganisms involved in the biological processes, such as sulfate-reducing and sulfur-oxidizing bacteria. Developments in molecular biology and genomic technologies have allowed us to obtain detailed information on these bacteria. The importance of RSS in environmental technologies requires further consideration.

19.
Heliyon ; 9(9): e19912, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37809845

RESUMO

Objectives: Cognitive impairment in schizophrenia patients with auditory hallucinations is more prominent compared to those without. Our study aimed to investigate the cognitive improvement effects of 10 Hz repetitive transcranial magnetic stimulation (rTMS) over the left dorsolateral prefrontal cortex (DLPFC) in schizophrenia with auditory hallucinations. Methods: A total of 60 schizophrenic patients with auditory hallucinations in this study were randomly assigned to sham or active group. Both groups received 10 Hz or sham rTMS targeted in left DLPFC for 20 sessions. The Positive and Negative Syndrome Scale (PANSS), the Auditory Hallucination Rating Scale (AHRS), the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), and the Udvalg for Kliniske Under-sogelser (UKU) side effect scale were used to measure psychiatric symptoms, auditory hallucinations, cognition, and side reaction, respectively. Results: Our results indicated that the active group experienced greater improvements in RBANS-total score (P = 0.043) and immediate memory subscale score (P = 0.001). Additionally, the PANSS-total score, negative and positive subscale score were obviously lower in the active group compared to the sham group (all P < 0.050). Furthermore, our study found that the improvement of RBANS-total score was positively associated with the decline of positive factor score, and the improvement of language score in RBANS was positively associated with the reduction in PANSS-total scale, negative and positive subscale score in the real stimulation group (all P < 0.050). Conclusion: Our results demonstrated that a four-week intervention of 10 Hz rTMS over the left DLPFC can improve cognition (particularly immediate memory) among schizophrenia patients with auditory hallucinations. Future studies with larger sample size are needful to verify our preliminary findings.

20.
Front Immunol ; 14: 1325495, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38235140

RESUMO

Objective: Increasing evidence indicated that schizophrenia and obesity are associated with altered mitochondrial and immune function. In this study, we investigated the levels of CRP (C-reactive protein) and mitochondrial lymphocytes in chronically treated schizophrenia patients with atypical antipsychotic medications and further explored the relationship between mitochondrial lymphocyte and weight gain as well as cognitive function in these patients. Methods: We evaluated the mitochondrial lymphocyte count of 97 patients (53 overweight, 44 non-overweight) and 100 healthy controls using mitochondrial fluorescence staining and flow cytometry (NovoCyte, Agilent Technologies, US). The serum CRP was measured by high-sensitivity enzyme-linked immunosorbent assay (ELISA). Clinical symptoms and cognitive function of the patients were assessed using the Positive and Negative Syndrome Scale (PANSS) and the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). Results: The results showed that mitochondrial lymphocyte counts of CD3+ T, CD3+CD4+ T, and CD3+CD8+ T cells in schizophrenia patients were higher than in the control group (p < 0.05). Additionally, overweight patients had significantly higher mitochondrial lymphocyte counts of CD3+ T and CD3+CD4+ T cells compared to schizophrenia patients with normal weight. Stratified analysis by gender revealed that there was a statistically significant difference in CD3+CD4+ mitochondrial lymphocyte count in male patients (p = 0.014) and a marginal trend toward significance in female patients (p = 0.058). Furthermore, the mitochondrial lymphocyte counts of CD3+ T and CD3+CD4+ T cells, as well as CRP levels, were positively correlated with BMI in schizophrenia patients, but the mitochondrial lymphocyte counts of CD3+CD4+ T cells were negatively correlated with the language scale in the RBANS. Conclusion: Our study results provide evidence for the association between altered mitochondrial T lymphocyte and weight gain as well as cognitive impairment in schizophrenia patients treated with atypical antipsychotic medications.


Assuntos
Antipsicóticos , Esquizofrenia , Humanos , Masculino , Feminino , Antipsicóticos/efeitos adversos , Esquizofrenia/tratamento farmacológico , Sobrepeso , Linfócitos T CD8-Positivos , Cognição , Aumento de Peso
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