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Arsenic, a toxicant widely distributed in the environment, is considered as a risk factor for liver fibrosis. At present, the underlying mechanism still needs to be explored. In the present study, we found that, for mice, chronic exposure to arsenic induced liver fibrosis, activated the NLRP3 inflammasome, and increased the levels of reactive oxygen species (ROS). After hepatocytes were co-cultured with hepatic stellate cells (HSCs), we observed the arsenic-activated NLRP3 inflammasome in hepatocytes, and the co-cultured HSCs were activated. Further, we found that, in livers of mice, arsenic disturbed GSH metabolism and promoted protein S-glutathionylation. A 3D molecular docking simulation suggested that NLRP3 binds with GSH, which was confirmed by immunoprecipitation experiments. N-acetylcysteine (NAC) increased the levels of GSH in hepatocytes, which suppressed the S-glutathionylation of NLRP3 and blocked arsenic-induced activation of the NLRP3 inflammasome. Mechanistically, an imbalance of the redox state induced by arsenic promotes the S-glutathionylation of NLRP3, which regulates activation of the NLRP3 inflammasome, leading into the activation of HSCs. Moreover, NAC increases the levels of GSH to block arsenic-induced S-glutathionylation of NLRP3, thereby blocking arsenic-induced liver fibrosis. Thus, via activating HSCs, the S-glutathionylation of NLRP3 in hepatocytes is involved in arsenic-induced liver fibrosis, and, for hepatocytes, NAC alleviates these effects by increasing the levels of GSH. These results reveal a new mechanism and provide a possible therapeutic target for the liver fibrosis induced by environmental factors.
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Arsênio , Glutationa , Hepatócitos , Inflamassomos , Cirrose Hepática , Proteína 3 que Contém Domínio de Pirina da Família NLR , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Cirrose Hepática/induzido quimicamente , Camundongos , Hepatócitos/efeitos dos fármacos , Animais , Inflamassomos/metabolismo , Glutationa/metabolismo , Arsênio/toxicidade , Acetilcisteína/farmacologia , Espécies Reativas de Oxigênio/metabolismoRESUMO
Zika virus (ZIKV) infection may lead to severe neurological consequences, including seizures, and early infancy death. However, the involved mechanisms are still largely unknown. TRPC channels play an important role in regulating nervous system excitability and are implicated in seizure development. We investigated whether TRPCs might be involved in the pathogenesis of ZIKV infection. We found that ZIKV infection increases TRPC4 expression in host cells via the interaction between the ZIKV-NS3 protein and CaMKII, enhancing TRPC4-mediated calcium influx. Pharmacological inhibition of CaMKII decreased both pCREB and TRPC4 protein levels, whereas the suppression of either TRPC4 or CaMKII improved the survival rate of ZIKV-infected cells and reduced viral protein production, likely by impeding the replication phase of the viral life cycle. TRPC4 or CaMKII inhibitors also reduced seizures and increased the survival of ZIKV-infected neonatal mice and blocked the spread of ZIKV in brain organoids derived from human-induced pluripotent stem cells. These findings suggest that targeting CaMKII or TRPC4 may offer a promising approach for developing novel anti-ZIKV therapies, capable of preventing ZIKV-associated seizures and death.
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Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina , Canais de Cátion TRPC , Infecção por Zika virus , Zika virus , Infecção por Zika virus/virologia , Infecção por Zika virus/metabolismo , Animais , Humanos , Zika virus/fisiologia , Zika virus/efeitos dos fármacos , Camundongos , Canais de Cátion TRPC/metabolismo , Canais de Cátion TRPC/antagonistas & inibidores , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/antagonistas & inibidores , Replicação Viral/efeitos dos fármacos , Células HEK293 , Proteínas Virais/metabolismo , Convulsões/virologia , Convulsões/metabolismo , Convulsões/tratamento farmacológico , Proteases Virais , Serina Endopeptidases , Nucleosídeo-Trifosfatase , RNA Helicases DEAD-boxRESUMO
Cryogenic Electron Tomography (CryoET) is a useful imaging technology in structural biology that is hindered by its need for manual annotations, especially in particle picking. Recent works have endeavored to remedy this issue with few-shot learning or contrastive learning techniques. However, supervised training is still inevitable for them. We instead choose to leverage the power of existing 2D foundation models and present a novel, training-free framework, CryoSAM. In addition to prompt-based single-particle instance segmentation, our approach can automatically search for similar features, facilitating full tomogram semantic segmentation with only one prompt. CryoSAM is composed of two major parts: 1) a prompt-based 3D segmentation system that uses prompts to complete single-particle instance segmentation recursively with Cross-Plane Self-Prompting, and 2) a Hierarchical Feature Matching mechanism that efficiently matches relevant features with extracted tomogram features. They collaborate to enable the segmentation of all particles of one category with just one particle-specific prompt. Our experiments show that CryoSAM outperforms existing works by a significant margin and requires even fewer annotations in particle picking. Further visualizations demonstrate its ability when dealing with full tomogram segmentation for various subcellular structures. Our code is available at: https://github.com/xulabs/aitom.
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The drivers of changes in gut microbiota under arsenic exposure and the mechanism by which microbiota affect arsenic metabolism are still unclear. Here, C57BL/6 mice were exposed to 0, 5, or 10 ppm NaAsO2 in drinking water for 6 months. The results showed that arsenic exposure induced liver injury and increased the abundance of folic acid (FA)/vitamin B12 (VB12)- and butyrate-synthesizing microbiota. Statistical analysis and in vitro cultures showed that microbiota were altered to meet the demand for FA/VB12 by arsenic metabolism and to resist the toxicity of unmetabolized arsenic. However, at higher arsenic levels, changes of these microbiota were inconsistent. A 3D molecular simulation showed that arsenic bound to methionine synthase (MTR), which was confirmed by SEC-UV-DAD (1 µM recombinant human MTR was purified with 0 or 2 µM NaAsO2 at room temperature for 1 h) and fluorescence-labeled arsenic co-localization (primary hepatocytes were exposed to 0, 0.5, or 1 µM ReAsH-EDT2 for 24 h) in non-cellular and cellular systems. Mechanistically, the arsenic-MTR interaction in the liver interferes with the utilization of FA/VB12, which increases arsenic retention and thus results in a substantial increase in the abundance of butyrate-synthesizing microbiota compared to FA/VB12-synthesizing microbiota. By exposing C57BL/6J mice to 0 or 10 ppm NaAsO2 with or without FA (6 mg/L) and VB12 (50 µg/L) supplementation in their drinking water for 6 months, we constructed an FA/VB12 intervention mouse model and found that FA/VB12 supplementation blocked the disturbance of gut microbiota, restored MTR levels, promoted arsenic metabolism, and alleviated liver injury. We demonstrate that the change of gut microbiota is a response to arsenic metabolism, a process influenced by the arsenic-MTR interaction. This study provides new insights for understanding the relationship between gut microbiota and arsenic metabolism and present therapeutic targets for arseniasis.
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5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase , Arsênio , Microbioma Gastrointestinal , Camundongos Endogâmicos C57BL , Animais , Microbioma Gastrointestinal/efeitos dos fármacos , Arsênio/metabolismo , Arsênio/toxicidade , Camundongos , 5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase/metabolismo , Fígado/metabolismo , Fígado/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Masculino , Ácido Fólico/metabolismo , Vitamina B 12/metabolismoRESUMO
As flexible electronics devices for energy storage, mechanical energy collection and self-powered sensing, stretchable flexible supercapacitor and triboelectric nanogenerator (TENG) have attracted extensive attention. However, it is difficult to satisfy the requirements of high safety and resistance to extreme conditions. Dual roles of mechanical and electrical enhancement of inorganic salt are put forward, and a carrageenan (CG) enhanced poly (N-hydroxyethyl acrylamide)/CG/lithium chloride/glycerol (PCLG) conductive gel is prepared by designing hydrogen bonding self-crosslinking and chain entanglement. A high concentration and rapid deposition strategy is proposed to prepare a PCLG gel-based stretchable flexible all-in-one supercapacitor for energy storage, and a single electrode PCLG gel-based TENG is designed for mechanical energy collection, self-powered strain and tactile sensing. The supercapacitor has high capacitance, excellent cycling stability. The TENG possesses efficient energy harvesting with high and stable output voltage and power density, and sensitive and stable self-powered strain and tactile sensing without external power supply. Even under extreme conditions such as low temperatures, self-healing after damage, prolonged placement, deformation, post-deformation, multiple continuous work, pinprick and burning, the supercapacitor and TENG still have excellent properties. Therefore, we provide novel ideas to design flexible supercapacitor and TENG used under extreme conditions for future wearable electronics.
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Carragenina , Capacitância Elétrica , Fontes de Energia Elétrica , Géis , Carragenina/química , Géis/química , Dispositivos Eletrônicos Vestíveis , NanotecnologiaRESUMO
BACKGROUND: Obesity, a chronic metabolic disorder, is related to cardiovascular diseases, diabetes, cancer, and reproductive disorders. The relationship between obesity and male infertility is now well recognized, but the mechanisms involved are unclear. We aimed to observe the effect of obesity on spermatogenesis and to investigate the role of histone ubiquitination and acetylation modifications in obesity-induced spermatogenesis disorders. METHODS: Thirty male C57BL/6J mice were randomly divided into two groups. The control group was fed with a general maintenance diet (12% fat), while a high-fat diet (HFD) group was fed with 40% fat for 10 weeks; then, they were mated with normal females. The fertility of male mice was calculated, testicular and sperm morphology were observed, and the expression levels of key genes and the levels of histone acetylation and ubiquitination modification during spermatogenesis were detected. RESULTS: The number of sperm was decreased, as well as the sperm motility, while the number of sperm with malformations was increased. In the testes, the mRNA and protein expression levels of gonadotropin-regulated testicular RNA helicase (GRTH/DDX25), chromosome region maintenance-1 protein (CRM1), high-mobility group B2 (HMGB2), phosphoglycerate kinase 2 (PGK2), and testicular angiotensin-converting enzyme (tACE) were decreased. Furthermore, obesity led to a decrease in ubiquitinated H2A (ubH2A) and reduced levels of histone H3 acetylation K18 (H3AcK18) and histone H4 acetylation K5, K8, K12, and K16 (H4tetraAck), which disrupted protamine 1 (Prm1) deposition in testis tissue. CONCLUSION: These results suggest that low levels of histone ubiquitination and acetylation are linked with obesity-induced disorders during spermatogenesis, contributing to a better understanding of obesity-induced damage to male reproduction.
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Bisabolene is a compound commonly found in essential oils of various plants. It has a broad application in sectors such as chemical, pharmaceutical, and health-care products. This study focuses on modifying the glycerol metabolism pathway to obtain a high bisabolene-producing strain of Saccharomyces cerevisiae. To achieve this, the glycerol transporter gene PtFPS2 from Pachysolen tannophilus and the glycerol dehydrogenase gene Opgdh from Ogataea parapolymorpha were overexpressed in engineered yeast YS036, which was equipped with a GAL promoters-enhanced mevalonic acid pathway. Additionally, the glucose-inhibiting transcription factor MIG1 was knocked out to reduce glucose inhibition. The results showed that the GAL promoter transcription levels of the recombinant yeast strains increased, and the co-utilization of sucrose and glycerol was further improved in MIG1-knockout strain. Moreover, the maximum yield of bisabolene in shaking flask fermentation increased to 866.7 mg/L, an 82.2% increase compared to that of the original strain. By modifying the metabolic pathway of carbon sources, the yield of bisabolene was considerably improved. This study offers an effective strategy for enhancing the yield of terpene compounds in engineered yeast.
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Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Glicerol/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Fermentação , Glucose/metabolismo , Engenharia MetabólicaRESUMO
BACKGROUND: Rapid eye movement (REM) sleep and three stages of non-REM (NREM) sleep comprise the full sleep cycle. The changes in sleep have been linked to depression risk. This study aimed to explore the association between sleep architecture and depressive symptoms. METHODS: A total of 3247 participants from the Sleep Heart Health Study (SHHS) were included in this cohort study. REM and NREM sleep were monitored by in-home polysomnography at SHHS visit 1. Depressive symptoms was reported as the first occurrence between SHHS visits 1 and 2 (mean follow-up of 5.3 years). Multivariable logistic regression was used to investigate the relationship between sleep stages and depressive symptoms. RESULTS: In total, 225 cases of depressive symptoms (6.9 %) were observed between SHHS visits 1 and 2. A significant linear association between NREM Stage 1 and depressive symptoms was found after adjusting for potential covariates. Multivariable logistic regression analysis showed that percentage in NREM Stage 1 was associated with the incidence of depressive symptoms (odds ratio [OR], 1.06; 95 % confidence interval [CI], 1.02-1.10; P = 0.001), as were time in NREM Stage 1 and depressive symptoms (OR, 1.02; 95 % CI, 1.01-1.03; P = 0.001). However, no significant association with depressive symptoms was found for other sleep stage. LIMITATIONS: The specific follow-up time for depressive symptoms diagnosis was missing. CONCLUSIONS: Increased time or percentage in NREM Stage 1 was associated with a higher risk of developing depressive symptoms. The early change in sleep architecture were important for incidence of depressive symptoms and warrants constant concerns.
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Depressão , Sono , Pessoa de Meia-Idade , Humanos , Idoso , Depressão/epidemiologia , Estudos de Coortes , Incidência , Sono REM , Fases do SonoRESUMO
The clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 system has been widely used to create animal models for biomedical and agricultural use owing to its low cost and easy handling. However, the occurrence of erroneous cleavage (off-targeting) may raise certain concerns for the practical application of the CRISPR-Cas9 system. In this study, we created a melanocortin 1 receptor (MC1R)-edited pig model through somatic cell nuclear transfer (SCNT) by using porcine kidney cells modified by the CRISPR-Cas9 system. We then carried out whole-genome sequencing of two MC1R-edited pigs and two cloned wild-type siblings, together with the donor cells, to assess the genome-wide presence of single-nucleotide variants and small insertions and deletions (indels) and found only one candidate off-target indel in both MC1R-edited pigs. In summary, our study indicates that the minimal off-targeting effect induced by CRISPR-Cas9 may not be a major concern in gene-edited pigs created by SCNT.
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Sistemas CRISPR-Cas , Receptor Tipo 1 de Melanocortina , Animais , Suínos/genética , Receptor Tipo 1 de Melanocortina/genética , Sistemas CRISPR-Cas/genética , Edição de Genes , Mutação , Mutação INDEL/genéticaRESUMO
Hydrogen-isotope storage materials are essential for the controlled nuclear fusion. However, the currently used smelting-ZrCo alloy suffers from rapid degradation of performance due to severe disproportionation. Here, we reveal a defect-derived disproportionation mechanism and report a nano-single-crystal strategy to solve ZrCo's problems. Single-crystal nano-ZrCo is synthesized by a wet-chemistry method and exhibits excellent comprehensive hydrogen-isotope storage performances, including ultrafast uptake/release kinetics, high anti-disproportionation ability, and stable cycling, far superior to conventional smelting-ZrCo. Especially, a further incorporation of Ti into nano-ZrCo can almost suppress the disproportionation reaction. Moreover, a mathematical relationship between dehydrogenation temperature and ZrCo particle size is established. Additionally, a microwave method capable of nondestructively detecting the hydrogen storage state of ZrCo is developed. The proposed disproportionation mechanism and anti-disproportionation strategy will be instructive for other materials with similar problems.
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AIM: Sphincter-sparing surgery can be achieved in most cases of low rectal cancer with the development of intersphincteric resection. However, abdominoperineal resection is still inevitable for patients with tumours located below the dentate line. To address this, we have developed a procedure called conformal sphincteric resection (CSR) in which the corresponding part of the subcutaneous portion of the external anal sphincter and the perianal skin on the tumour side is removed to achieve a safe distal resection margin and lateral resection margin while the dentate line and the internal anal sphincter on the tumour-free side are preserved as much as possible, to achieve sphincter preservation without compromising oncological safety and functional acceptability, and to render tumour location no longer a contraindication for sphincter-sparing surgery. This is the first study to describe the concept, indication and surgical procedure of CSR and to report its preliminary surgical, oncological and functional results. METHODS: This is a retrospective, single-centre, single-arm pilot study conducted at Huashan Hospital, Fudan University. Demographic, clinicopathological, oncological and functional follow-up data were collected from 20 consecutive patients with rectal tumours located below the dentate line who underwent laparoscopic CSR by the same surgical team from June 2018 to March 2022. RESULTS: The mean distance of the tumour's lower edge from the anal verge was 13.1 ± 6.0 mm. The mean distal resection margin was 10.6 ± 4.3 mm. All circumferential resection margins were negative. There were no instances of perioperative mortality. The complication rate was 25% but all were Clavien-Dindo Grade I. Among the 20 cases, 17 were diagnosed with adenocarcinoma, one with squamous cell carcinoma and two with adenoma featuring high-grade intraepithelial neoplasia. Pathological TNM staging revealed two, seven, five, five and one case(s) in Stages 0, I, II, III and IV, respectively. The median follow-up period was 20 months (interquartile range 22 months), with no withdrawals. The overall and disease-free survival rates were both 95%. The mean Wexner incontinence score and low anterior resection syndrome score recorded 18 months following diverting ileostomy closure were 6.3 ± 3.8 and 27.3 ± 3.6, respectively. CONCLUSIONS: This study has proposed the CSR procedure for the first time, which is a technically feasible, oncologically safe and functionally acceptable procedure for carefully selected patients with rectal tumours located below the dentate line.
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Neoplasias Retais , Humanos , Neoplasias Retais/cirurgia , Neoplasias Retais/patologia , Canal Anal/cirurgia , Canal Anal/patologia , Complicações Pós-Operatórias/patologia , Estudos Retrospectivos , Margens de Excisão , Projetos Piloto , Tratamentos com Preservação do Órgão , Síndrome , Resultado do TratamentoRESUMO
Structural variations have emerged as an important driving force for genome evolution and phenotypic variation in various organisms, yet their contributions to genetic diversity and adaptation in domesticated animals remain largely unknown. Here we constructed a pangenome based on 250 sequenced individuals from 32 pig breeds in Eurasia and systematically characterized coding sequence presence/absence variations (PAVs) within pigs. We identified 308.3-Mb nonreference sequences and 3438 novel genes absent from the current reference genome. Gene PAV analysis showed that 16.8% of the genes in the pangene catalog undergo PAV. A number of newly identified dispensable genes showed close associations with adaptation. For instance, several novel swine leukocyte antigen (SLA) genes discovered in nonreference sequences potentially participate in immune responses to productive and respiratory syndrome virus (PRRSV) infection. We delineated previously unidentified features of the pig mobilome that contained 490,480 transposable element insertion polymorphisms (TIPs) resulting from recent mobilization of 970 TE families, and investigated their population dynamics along with influences on population differentiation and gene expression. In addition, several candidate adaptive TE insertions were detected to be co-opted into genes responsible for responses to hypoxia, skeletal development, regulation of heart contraction, and neuronal cell development, likely contributing to local adaptation of Tibetan wild boars. These findings enhance our understanding on hidden layers of the genetic diversity in pigs and provide novel insights into the role of SVs in the evolutionary adaptation of mammals.
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Cruzamento , Genoma , Humanos , Animais , Suínos , Variação Genética , MamíferosRESUMO
CsPbBr3 all-inorganic perovskite solar cells (PSCs) have been extensively investigated due to their remarkable stability. However, their limited film quality and wide bandgap result in a low photoelectric conversion efficiency (PCE). In this study, BiI3 was incorporated into CsPbBr3 films to synergistically enhance light absorption and film quality. It was found that the partial substitution of Pb2+ and Br- with Bi3+ and I- in CsPbBr3 improved film quality, enhanced light absorption, and facilitated charge transfer and extraction. The device incorporating BiI3-incorporated CsPbBr3 as a light absorbing layer achieved an efficiency of 9.54%, exhibiting a significant enhancement of 19.4% compared to the undoped device. This work provides a new incorporating strategy that collaboratively improves light absorption and film quality.
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Heterogeneous nuclear ribonucleoproteins (hnRNPs) are a superfamily of RNA-binding proteins consisting of more than 20 members. These proteins play a crucial role in various biological processes by regulating RNA splicing, transcription, and translation through their binding to RNA. In the context of muscle development and regeneration, hnRNPs are involved in a wide range of regulatory mechanisms, including alternative splicing, transcription regulation, miRNA regulation, and mRNA stability regulation. Recent studies have also suggested a potential association between hnRNPs and muscle-related diseases. In this report, we provide an overview of our current understanding of how hnRNPs regulate RNA metabolism and emphasize the significance of the key members of the hnRNP family in muscle development. Furthermore, we explore the relationship between the hnRNP family and muscle-related diseases.
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Ribonucleoproteínas Nucleares Heterogêneas , MicroRNAs , Ribonucleoproteínas Nucleares Heterogêneas/genética , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Proteínas de Ligação a RNA/metabolismo , Splicing de RNA , MicroRNAs/genética , MicroRNAs/metabolismo , Desenvolvimento Muscular/genéticaRESUMO
BACKGROUND: Although dietary intake is believed to be associated with constipation, there is currently a lack of research exploring the relationship between niacin intake and constipation. Therefore, the aim of this study is to investigate the association between niacin intake in adults and constipation using data from the National Health and Nutrition Examination Survey (NHANES). METHODS: This study included 5170 participants (aged ≥ 20 years) from the NHANES survey conducted between 2009 and 2010. Participants who reported experiencing constipation "always", "most of the time", or "sometimes" in the past 12 months were defined as constipation cases. The daily niacin intake was obtained from dietary recall and dietary supplement recalls of the patients. Weighted multivariate logistic regression analysis, restricted cubic spline regression, subgroup analysis, and interaction analysis were used to assess the correlation between niacin intake and constipation. RESULTS: After adjustment for covariates, the multivariate logistic regression model showed that low niacin intake was associated with a higher risk of constipation (Model 1: OR: 0.917, 95% CI 0.854-0.985, P = 0.023; Model 2: OR: 0.871, 95% CI 0.794-0.955, P = 0.01). After dividing niacin intake into four groups, a daily intake of 0-18 mg niacin was associated with a higher risk of constipation (Model 1: OR: 1.059, 95% CI 1.012-1.106, P = 0.019; Model 2: OR: 1.073, 95% CI 1.025-1.123, P = 0.013). The restricted cubic spline regression analysis also showed a non-linear relationship between niacin intake and the risk of constipation. CONCLUSION: The findings of this study suggested that daily intake of 0-18 mg of niacin was associated with a higher risk of constipation compared to a daily intake of 18-27 mg of niacin.
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Niacina , Humanos , Adulto , Niacina/efeitos adversos , Inquéritos Nutricionais , Constipação Intestinal/induzido quimicamente , Constipação Intestinal/epidemiologia , Suplementos Nutricionais/efeitos adversos , Modelos LogísticosRESUMO
Mangroves as typical blue carbon ecosystems exhibit a high level of heavy metal accumulation capability. In this study, we investigated how extreme rainstorm effects the spatial variability and pollution risk of sediment heavy metals (i.e., Fe, Mn, Cr, Cu, Zn, Cd, Pb, As and Hg) at different compartments of a typical tidal flat, including the bare mudflat, mangrove zone, and tidal creek in Shenzhen Bay, China. The results showed that the extreme rainstorm can change the sediment particle size, which further regulated the spatial distribution, and source-sink pattern of heavy metals. Due to the strong rainstorm flushing, the concentrations of most heavy metals increased toward the sea and the comprehensive pollution level increased by 8.3 % after the extreme rainstorm. This study contributes to better understanding of how extreme rainstorm regulates heavy metal behavior in mangrove sediments to achieve sustainable development of mangroves under the pressures of extreme weather events.
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Mercúrio , Metais Pesados , Ecossistema , Carbono , ChinaRESUMO
Background: Postoperative recurrence was a life-threatening condition for patients with rectal cancer. Due to the heterogeneity of locally recurrent rectal cancer (LRRC) and controversy of the optimal treatment for patients, it was difficult to predict the prognosis of LRRC. This study aimed to develop and validate a nomogram that could accurately predict the survival probability of LRRC. Methods: Patients diagnosed with LRRC between 2004 and 2019 from the Surveillance, Epidemiology, and End Results (SEER) database were included in the analysis. Multiple imputations with chained equations were used for missing values. These patients were further randomized into training set and testing set. Cox regression was used for univariate and multivariate analysis. Potential predictors were screened by the least absolute shrinkage and selection operator (LASSO). The Cox hazards regression model was constructed and it was visualized by nomogram. C-index, calibration curve, and decision curve were used to evaluate the model's predictive ability. Then X-tile was used to calculate the optimal cut-off values for all patients and the cohort was divided into three groups. Results: A total of 744 LRRC patients were enrolled and allocated to the training set (n=503) and the testing set (n=241). Cox regression analysis of the training set yielded meaningfully clinicopathological variables. A survival nomogram was created based on the identification of ten clinicopathological features in the LASSO regression analyses of the training set. The C-index of 3-, 5-year survival probabilities were 0.756, 0.747 in training set, and 0.719, 0.726 in testing set, respectively. The calibration curve and decision curve both demonstrated the satisfactory performance of the nomogram for prognosis prediction. Moreover, the prognosis of LRRC could be well distinguished according to the grouping of risk scores (P<0.001 in three groups). Conclusions: This nomogram was the first prediction model to preliminarily evaluate the survival of LRRC patients, which could provide more accurate and efficient treatment in clinical practice.
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Visual Commonsense Reasoning (VCR), deemed as one challenging extension of Visual Question Answering (VQA), endeavors to pursue a higher-level visual comprehension. VCR includes two complementary processes: question answering over a given image and rationale inference for answering explanation. Over the years, a variety of VCR methods have pushed more advancements on the benchmark dataset. Despite significance of these methods, they often treat the two processes in a separate manner and hence decompose VCR into two irrelevant VQA instances. As a result, the pivotal connection between question answering and rationale inference is broken, rendering existing efforts less faithful to visual reasoning. To empirically study this issue, we perform some in-depth empirical explorations in terms of both language shortcuts and generalization capability. Based on our findings, we then propose a plug-and-play knowledge distillation enhanced framework to couple the question answering and rationale inference processes. The key contribution lies in the introduction of a new branch, which serves as a relay to bridge the two processes. Given that our framework is model-agnostic, we apply it to the existing popular baselines and validate its effectiveness on the benchmark dataset. As demonstrated in the experimental results, when equipped with our method, these baselines all achieve consistent and significant performance improvements, evidently verifying the viability of processes coupling.
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Passive radiative cooling involves the emission of thermal radiation into cold space and the reflection of solar radiation, which aims to cool and lower the temperature of objects. However, currently most radiative coolers have a white appearance which restricts their potential applications. We develop a coloured bilayer radiative cooling membrane using polyvinylidene fluoride/tetraethoxysilane (PVDF/TEOS) fibres, with incorporation of phase change materials (PCMs) and active dyes through a simple and large-area electrospinning process. In comparison to traditional emitters, PCM-incorporated colourful coolers provide energy storage capacity and colourful appearances. Our phase-transition-based colourful flexible film (PCFF) achieves a total solar reflectance of 0.81 and a mid-infrared (8-13µm) emissivity of 0.85 with superior mechanical strength and good hydrophobicity. We experimentally demonstrate that our PCFF can significantly reduce the temperature of objects exposed to direct sunlight, with a cooling effect of up to 9 °C compared to commercial fabrics of similar materials and colours. Our work provides a promising starting point for the design and manufacture of colourful and flexible thermal control films.
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The recurrent neural network architecture improves the processing ability of time-series data. However, issues such as exploding gradients and poor feature extraction limit its application in the automatic diagnosis of mild cognitive impairment (MCI). This paper proposed a research approach for building an MCI diagnostic model using a Bayesian-optimized bidirectional long short-term memory network (BO-BiLSTM) to address this problem. The diagnostic model was based on a Bayesian algorithm and combined prior distribution and posterior probability results to optimize the BO-BiLSTM network hyperparameters. It also used multiple feature quantities that fully reflected the cognitive state of the MCI brain, such as power spectral density, fuzzy entropy, and multifractal spectrum, as the input of the diagnostic model to achieve automatic MCI diagnosis. The results showed that the feature-fused Bayesian-optimized BiLSTM network model achieved an MCI diagnostic accuracy of 98.64% and effectively completed the diagnostic assessment of MCI. In conclusion, based on this optimization, the long short-term neural network model has achieved automatic diagnostic assessment of MCI, providing a new diagnostic model for intelligent diagnosis of MCI.