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1.
Brief Bioinform ; 24(1)2023 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-36572655

RESUMO

The time since deposition (TSD) of a bloodstain, i.e., the time of a bloodstain formation is an essential piece of biological evidence in crime scene investigation. The practical usage of some existing microscopic methods (e.g., spectroscopy or RNA analysis technology) is limited, as their performance strongly relies on high-end instrumentation and/or rigorous laboratory conditions. This paper presents a practically applicable deep learning-based method (i.e., BloodNet) for efficient, accurate, and costless TSD inference from a macroscopic view, i.e., by using easily accessible bloodstain photos. To this end, we established a benchmark database containing around 50,000 photos of bloodstains with varying TSDs. Capitalizing on such a large-scale database, BloodNet adopted attention mechanisms to learn from relatively high-resolution input images the localized fine-grained feature representations that were highly discriminative between different TSD periods. Also, the visual analysis of the learned deep networks based on the Smooth Grad-CAM tool demonstrated that our BloodNet can stably capture the unique local patterns of bloodstains with specific TSDs, suggesting the efficacy of the utilized attention mechanism in learning fine-grained representations for TSD inference. As a paired study for BloodNet, we further conducted a microscopic analysis using Raman spectroscopic data and a machine learning method based on Bayesian optimization. Although the experimental results show that such a new microscopic-level approach outperformed the state-of-the-art by a large margin, its inference accuracy is significantly lower than BloodNet, which further justifies the efficacy of deep learning techniques in the challenging task of bloodstain TSD inference. Our code is publically accessible via https://github.com/shenxiaochenn/BloodNet. Our datasets and pre-trained models can be freely accessed via https://figshare.com/articles/dataset/21291825.


Assuntos
Manchas de Sangue , Teorema de Bayes , Aprendizado de Máquina
2.
Proc Natl Acad Sci U S A ; 119(49): e2214906119, 2022 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-36459640

RESUMO

The primary goal of protein science is to understand how proteins function, which requires understanding the functional dynamics responsible for transitions between different functional structures of a protein. A central concept is the exact reaction coordinates that can determine the value of committor for any protein configuration, which provide the optimal description of functional dynamics. Despite intensive efforts, identifying the exact reaction coordinates (RCs) in complex molecules remains a formidable challenge. Using the recently developed generalized work functional, we report the discovery of the exact RCs for an important functional process-the flap opening of HIV-1 protease. Our results show that this process has six RCs, each one is a linear combination of ~240 backbone dihedrals, providing the precise definition of collectivity and cooperativity in the functional dynamics of a protein. Applying bias potentials along each RC can accelerate flap opening by [Formula: see text] to [Formula: see text] folds. The success in identifying the RCs of a protein with 198 residues represents a significant progress beyond that of the alanine dipeptide, currently the only other complex molecule for which the exact RCs for its conformational changes are known. Our results suggest that the generalized work functional (GWF) might be the fundamental operator of mechanics that controls protein dynamics.


Assuntos
Alanina , Protease de HIV , Dipeptídeos
3.
Brief Bioinform ; 23(2)2022 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-35224615

RESUMO

The lack of a reliable and easy-to-operate screening pipeline for disease-related noncoding RNA regulatory axis is a problem that needs to be solved urgently. To address this, we designed a hybrid pipeline, disease-related lncRNA-miRNA-mRNA regulatory axis prediction from multiomics (DLRAPom), to identify risk biomarkers and disease-related lncRNA-miRNA-mRNA regulatory axes by adding a novel machine learning model on the basis of conventional analysis and combining experimental validation. The pipeline consists of four parts, including selecting hub biomarkers by conventional bioinformatics analysis, discovering the most essential protein-coding biomarkers by a novel machine learning model, extracting the key lncRNA-miRNA-mRNA axis and validating experimentally. Our study is the first one to propose a new pipeline predicting the interactions between lncRNA and miRNA and mRNA by combining WGCNA and XGBoost. Compared with the methods reported previously, we developed an Optimized XGBoost model to reduce the degree of overfitting in multiomics data, thereby improving the generalization ability of the overall model for the integrated analysis of multiomics data. With applications to gestational diabetes mellitus (GDM), we predicted nine risk protein-coding biomarkers and some potential lncRNA-miRNA-mRNA regulatory axes, which all correlated with GDM. In those regulatory axes, the MALAT1/hsa-miR-144-3p/IRS1 axis was predicted to be the key axis and was identified as being associated with GDM for the first time. In short, as a flexible pipeline, DLRAPom can contribute to molecular pathogenesis research of diseases, effectively predicting potential disease-related noncoding RNA regulatory networks and providing promising candidates for functional research on disease pathogenesis.


Assuntos
MicroRNAs , RNA Longo não Codificante , Biologia Computacional , Redes Reguladoras de Genes , MicroRNAs/genética , RNA Longo não Codificante/genética , RNA Mensageiro/genética
4.
J Autoimmun ; 146: 103232, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38692172

RESUMO

The link between type I IFN and adaptive immunity, especially T-cell immunity, in JDM still remained largely unclear. This study aimed to understand the effect of elevated type I IFN signaling on CD8+ T cell-associated muscle damage in juvenile dermatomyositis (JDM). This study used flow cytometry (FC) and RT‒PCR were used to examine the circulating cell ratio and type I IFN response. And scRNA-seq was used to examine peripheral immunity in 6 active JDM patients, 3 stable JDM patients, 3 juvenile IMNM patients and 3 age-matched healthy children. In vivo validation experiments were conducted using a mouse model induced by STING agonists and an experimental autoimmune myositis model (EAM). In vitro experiments were conducted using isolated CD8+ T-cells from JDM patients and mice. We found that active JDM patients showed an extensive type I IFN response and a decreased CD8+ T-cell ratio in the periphery (P < 0.05), which was correlated with muscle involvement (P < 0.05). Both new active JDM patients and all active JDM patients showed decreased CD8+ TCM cell ratios compared with age and gender matched stable JDM patients (P < 0.05). Compared with new pediatirc systemic lupus erythematosus (SLE) patients, new active JDM patients displayed decreased CD8+ T-cell and CD8+ TCM cell ratios (P < 0.05). Active JDM patient skeletal muscle biopsies displayed an elevated type I IFN response, upregulated MHC-I expression and CD8+ T-cell infiltration, which was validated in EAM mice. sc-RNAseq demonstrated that type I IFN signalling is the kinetic factor of abnormal differentiation and enhances the cytotoxicity of peripheral CD8+ T cells in active JDM patients, which was confirmed by in vivo and in vitro validation experiments. In summary, the elevated type I IFN signalling affected the differentiation and function of CD8+ T cells in active JDM patients. Skeletal muscle-infiltrating CD8+ T cells might migrate from the periphery under the drive of type I IFN and increased MHC I signals. Therapies targeting autoantigen-specific CD8+ T cells may represent a potential new treatment direction.


Assuntos
Autoantígenos , Linfócitos T CD8-Positivos , Dermatomiosite , Interferon Tipo I , Músculo Esquelético , Transdução de Sinais , Humanos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Interferon Tipo I/metabolismo , Animais , Músculo Esquelético/imunologia , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Camundongos , Transdução de Sinais/imunologia , Autoantígenos/imunologia , Feminino , Dermatomiosite/imunologia , Dermatomiosite/patologia , Dermatomiosite/metabolismo , Masculino , Criança , Modelos Animais de Doenças , Adolescente , Pré-Escolar
5.
Plant Physiol ; 191(2): 1122-1137, 2023 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-36494195

RESUMO

As essential organs of reproduction in angiosperms, flowers, and the genetic mechanisms of their development have been well characterized in many plant species but not in the woody tree yellowhorn (Xanthoceras sorbifolium). Here, we focused on the double flower phenotype in yellowhorn, which has high ornamental value. We found a candidate C-class gene, AGAMOUS1 (XsAG1), through bovine serum albumin sequencing and genetics analysis with a Long Interpersed Nuclear Elements 1 (LINE1) transposable element fragment (Xsag1-LINE1-1) inserted into its second intron that caused a loss-of-C-function and therefore the double flower phenotype. In situ hybridization of XsAG1 and analysis of the expression levels of other ABC genes were used to identify differences between single- and double-flower development processes. These findings enrich our understanding of double flower formation in yellowhorn and provide evidence that transposon insertions into genes can reshape plant traits in forest trees.


Assuntos
Magnoliopsida , Sapindaceae , Fenótipo , Sapindaceae/genética , Magnoliopsida/genética , Elementos de DNA Transponíveis/genética , Flores/genética , Regulação da Expressão Gênica de Plantas
6.
Ann Hematol ; 103(7): 2463-2473, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38758360

RESUMO

The combination of cladribine, cytarabine, and G-CSF (CLAG) has exhibited robust synergistic anti-leukemia activity as an induction therapy (IT) in acute myeloid leukemia (AML). However, the impact of CLAG as a bridging therapy (BT) administered between IT and allogeneic hematopoietic stem cell transplantation (allo-HSCT) for patients with relapsed or refractory (R/R) AML remains uncertain. In this retrospective study, we examined the efficacy of CLAG as a transitional strategy prior to allo-HSCT in R/R AML. We included 234 patients with R/R AML who received the modified busulfan plus cyclophosphamide conditioning regimen for allo-HSCT in our center during the past 6 years, performed a propensity-score matching analysis, partitioned them into four distinct cohorts, and further integrated them into the CLAG group and non-CLAG group based on response to IT and utilization of CLAG. Our cohorts encompassed 12 patients in Cohort A (modified composite complete remission (mCRc) after IT, CLAG), 31 in Cohort B (mCRc after IT, non-CLAG), 35 in Cohort C (non-complete remission (non-CR) after IT, CLAG), and 80 in Cohort D (non-CR after IT, non-CLAG). Intriguingly, among patients with non-CR status, the administration of CLAG correlated with a notably statistically diminished risk of relapse and improved survival at 2-year follow-up (Cohort C vs. Cohort D). Employing CLAG as a BT prior to allo-HSCT demonstrates substantial effectiveness, a relative degree of safety, and manageable toxicity in selected R/R AML cases.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Cladribina , Citarabina , Fator Estimulador de Colônias de Granulócitos , Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , Humanos , Citarabina/administração & dosagem , Citarabina/uso terapêutico , Leucemia Mieloide Aguda/terapia , Leucemia Mieloide Aguda/tratamento farmacológico , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Cladribina/uso terapêutico , Cladribina/administração & dosagem , Estudos Retrospectivos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Idoso , Adulto Jovem , Transplante Homólogo , Recidiva , Adolescente , Condicionamento Pré-Transplante/métodos , Aloenxertos
7.
Int J Colorectal Dis ; 39(1): 83, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38809459

RESUMO

BACKGROUND: Programmed cell death receptor 1 (PD-1) and programmed cell death ligand 1 (PD-L1) are important immune checkpoint molecules that contribute to tumor immune evasion. However, the main treatment modalities for patients with early and intermediate stage colorectal cancer (CRC) are surgery, and the role of PD-1/PD-L1 inhibitors in these patients is not yet clear. Therefore, this study aims to review the treatment progress of PD-1/PD-L1 inhibitors for early- and intermediate-stage microsatellite high-instability (MSI-H) and stable (MSS) colorectal cancer, in order to provide more options for patients with early- and intermediate-stage colorectal cancer. MATERIALS AND METHODS: A scoping review of clinical trial registries ( Clinicaltrials.gov and EU clinical trial registers) and PubMed/Medline database of trials on PD-1/PD-L1 Inhibitors for early and middle-stage MSI-H and MSS CRC was done up to March 2024. RESULTS: A total of 19 trials related to early to mid-stage MSH-I or MSS CRC were included. Among them, 6 trials are in recruiting status, 3 trials are in active, not recruiting status, 3 trials are completed, 1 trial is terminated, and 1 trial is unknown. Of these, 9 trials involve MSI-H type CRC, and 10 trials involve MSS type CRC. Preclinical phase I/II trials are predominant, with only 3 clinical phase III trials. In trials related to MSI-H type CRC, 4 studies involve PD-1/PD-L1 inhibitors combined with neoadjuvant therapy, and 5 studies involve combination therapy. In trials related to MSS type CRC, 3 studies involve PD-1/PD-L1 inhibitors combined with targeted therapy, 2 studies involve PD-1/PD-L1 inhibitors combined with chemotherapy, 1 study involves PD-1/PD-L1 inhibitor combined immunotherapy, 1 study involves PD-1/PD-L1 inhibitors combined with bacterial therapy, and 3 studies involve PD-1/PD-L1 inhibitors combined with comprehensive therapy. As for primary outcome measures, 4 trials select pathological complete response rates, 3 trials select progression-free survival rate, 3 trials select objective response rate, 3 trials select overall survival rate, 4 trials select disease-free survival rate, 1 trial selects clinical complete response rate, and 1 trial selects percentage of participants with a dose-limiting toxicity. CONCLUSION: For early- and middle-stage MSI-H and MSS CRC, PD-1/PD-L1 inhibitors have shown some therapeutic efficacy, as evidenced by phase I/II studies. However, contemporary trial designs exhibit heterogeneity, with relatively few inclusion criteria, the use of various drug combinations and regimens, and significant variations in reported endpoints. Nevertheless, more double-arm, multicenter, randomized controlled trials are still needed to confirm the efficacy of immunotherapy.


Assuntos
Antígeno B7-H1 , Neoplasias Colorretais , Inibidores de Checkpoint Imunológico , Instabilidade de Microssatélites , Estadiamento de Neoplasias , Receptor de Morte Celular Programada 1 , Humanos , Neoplasias Colorretais/genética , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Antígeno B7-H1/antagonistas & inibidores , Inibidores de Checkpoint Imunológico/uso terapêutico
8.
BMC Microbiol ; 23(1): 38, 2023 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-36765295

RESUMO

BACKGROUND: Microorganisms distribute and proliferate both inside and outside the body, which are the main mediators of decomposition after death. However, limited information is available on the postmortem microbiota changes of extraintestinal body sites in the early decomposition stage of mammalian corpses. RESULTS: This study investigated microbial composition variations among different organs and the relationship between microbial communities and time since death over 1 day of decomposition in male C57BL/6 J mice by 16S rRNA sequencing. During 1 day of decomposition, Agrobacterium, Prevotella, Bacillus, and Turicibacter were regarded as time-relevant genera in internal organs at different timepoints. Pathways associated with lipid, amino acid, carbohydrate and terpenoid and polyketide metabolism were significantly enriched at 8 h than that at 0.5 or 4 h. The microbiome compositions and postmortem metabolic pathways differed by time since death, and more importantly, these alterations were organ specific. CONCLUSION: The dominant microbes differed by organ, while they tended toward similarity as decomposition progressed. The observed thanatomicrobiome variation by body site provides new knowledge into decomposition ecology and forensic microbiology. Additionally, the microbes detected at 0.5 h in internal organs may inform a new direction for organ transplantation.


Assuntos
Microbiota , Mudanças Depois da Morte , Masculino , Animais , Camundongos , RNA Ribossômico 16S/genética , Camundongos Endogâmicos C57BL , Cadáver , Microbiota/genética , Mamíferos/genética
9.
BMC Cancer ; 23(1): 878, 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37723418

RESUMO

Colorectal cancer (CRC) is one of the malignant tumors with the highest morbidity and mortality and poor prognosis. The mammalian gene family of Cab45/reticulocalbin/ERC-45/calumenin (CREC) consists of RCN1, RCN2, RCN3, SDF4 and CALU. Although CREC family members have been associated with CRC, the expression pattern, prognostic value, and the role of CREC family in CRC remain unclear. In this study, the expression, survival and biological functions of CREC family in CRC were determined via bioinformatic datasets analysis and experimental verification on clinical CRC specimen. Bioinformatic analysis showed that the expression levels of most CREC family genes were higher in CRC tissues than in normal colorectal tissues. The qPCR and western blot results also revealed that the transcriptional and protein levels of CREC family were elevated in CRC tissues compared with adjacent tissues. Besides, CREC family was significantly correlated with advanced tumor stage and poor prognosis of CRC patients. The expression levels of CREC family had correlations with genomic mutation and methylation, and with the infiltration levels of CD4 + T cells, macrophages, neutrophils, and dendritic cells in the microenvironment of CRC. Functional networks enrichment analysis indicated that the genes of CREC family were essential factors for CRC metastasis. Collectively, these findings suggest that CREC family might be potential targets for the treatment of CRC and candidate prognostic markers for CRC patients.


Assuntos
Linfócitos T CD4-Positivos , Neoplasias Colorretais , Animais , Humanos , Prognóstico , Western Blotting , Biologia Computacional , Neoplasias Colorretais/genética , Mamíferos , Microambiente Tumoral , Proteínas de Ligação ao Cálcio
10.
RNA Biol ; 20(1): 359-367, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-37335045

RESUMO

OBJECTIVE: Often, alternative splicing is used by cancer cells to produce or increase proteins that promote growth and survival through alternative splicing. Although RNA-binding proteins are known to regulate alternative splicing events associated with tumorigenesis, their role in oesophageal cancer (EC) has rarely been explored. METHODS: We analysed the expression pattern of several relatively well characterized splicing regulators on 183 samples from TCGA cohort of oesophageal cancer; the effectiveness of the knockdown of SRSF2 was subsequently verified by immunoblotting; we measured the ability of cells treated with lenti-sh-SRSF2/lenti-sh2-SRSF2 to invade through an extracellular matrix coating by transwell invasion assay; using RNA-seq data to identify its potential target genes; we performed qRT-PCR to detect the changes of exon 2 usage in lenti-sh-SRSF2 transduced KYSE30 cells to determine the possible effect of SRSF2 on splicing regulation of IRF3; RNA Electrophoretic mobility shift assay (RNA-EMSA) was performed by the incubation of purified SRSF2 protein and biotinylated RNA probes; we performed luciferase assay to confirm the effect of SRSF2 on IFN1 promoter activity. RESULTS: We found upregulation of SRSF2 is correlated with the development of EC; Knock-down of SRSF2 inhibits EC cell proliferation, migration, and invasion; SRSF2 regulates the splicing pattern of IRF3 in EC cells; SRSF2 interacts with exon 2 of IRF3 to regulate its exclusion; SRSF2 inhibits the transcription of IFN1 in EC cells. CONCLUSION: This study identified a novel regulatory axis involved in EC from the various aspects of splicing regulation.


Assuntos
Processamento Alternativo , Neoplasias Esofágicas , Humanos , Fatores de Processamento de Serina-Arginina/genética , Fatores de Processamento de Serina-Arginina/metabolismo , Arginina/metabolismo , Fator Regulador 3 de Interferon/genética , Splicing de RNA , RNA/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Neoplasias Esofágicas/genética
11.
Int J Colorectal Dis ; 39(1): 7, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38127156

RESUMO

OBJECTIVE: This study aims to conduct a meta-analysis to evaluate the short-term and long-term therapeutic effects of robot-assisted laparoscopic treatment in patients with mid and low rectal cancer. METHODS: A comprehensive search strategy was employed to retrieve relevant literature from PubMed, NCBI, Medline, and Springer databases, spanning the database inception until August 2023. The focus of this systematic review was on controlled studies that compared the treatment outcomes of robot-assisted (Rob) and conventional laparoscopy (Lap) in the context of mid and low rectal cancer. Data extraction and literature review were meticulously conducted by two independent researchers (HMW and RKG). The synthesized data underwent rigorous analysis utilizing RevMan 5.4 software, adhering to established methodological standards in systematic reviews. The primary outcomes encompass perioperative outcomes and oncological outcomes. Secondary outcomes include long-term outcomes. RESULT: A total of 11 studies involving 2239 patients with mid and low rectal cancer were included (3 RCTs and 8 NRCTs); the Rob group consisted of 1111 cases, while the Lap group included 1128 cases. The Rob group exhibited less intraoperative bleeding (MD = -40.01, 95% CI: -57.61 to -22.42, P < 0.00001), a lower conversion rate to open surgery (OR = 0.27, 95% CI: 0.09 to 0.82, P = 0.02), a higher number of harvested lymph nodes (MD = 1.97, 95% CI: 0.77 to 3.18, P = 0.001), and a lower CRM positive rate (OR = 0.46, 95% CI: 0.23 to 0.95, P = 0.04). Additionally, the Rob group had lower postoperative morbidity rate (OR = 0.66, 95% CI: 0.53 to 0.82, P < 0.0001) and a lower occurrence rate of complications with Clavien-Dindo grade ≥ 3 (OR = 0.60, 95% CI: 0.39 to 0.90, P = 0.02). Further subgroup analysis revealed a lower anastomotic leakage rate (OR = 0.66, 95% CI: 0.45 to 0.97, P = 0.04). No significant differences were observed between the two groups in the analysis of operation time (P = 0.42), occurrence rates of protective stoma (P = 0.81), PRM (P = 0.92), and DRM (P = 0.23), time to flatus (P = 0.18), time to liquid diet (P = 0.65), total hospital stay (P = 0.35), 3-year overall survival rate (P = 0.67), and 3-year disease-free survival rate (P = 0.42). CONCLUSION: Robot-assisted laparoscopic treatment for mid and low rectal cancer yields favorable outcomes, demonstrating both efficacy and safety. In comparison to conventional laparoscopy, patients experience reduced intraoperative bleeding and a lower incidence of complications. Notably, the method achieves comparable short-term and long-term treatment results to those of conventional laparoscopic surgery, thus justifying its consideration for widespread clinical application.


Assuntos
Neoplasias , Robótica , Humanos , Fístula Anastomótica , Conversão para Cirurgia Aberta , Bases de Dados Factuais
12.
Acta Pharmacol Sin ; 44(5): 1083-1094, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36411339

RESUMO

Although several KRasG12C inhibitors have displayed promising efficacy in clinical settings, acquired resistance developed rapidly and circumvented the activity of KRasG12C inhibitors. To explore the mechanism rendering acquired resistance to KRasG12C inhibitors, we established a series of KRASG12C-mutant cells with acquired resistance to AMG510. We found that differential activation of receptor tyrosine kinases (RTKs) especially EGFR or IGF1R rendered resistance to AMG510 in different cellular contexts by maintaining the activation of MAPK and PI3K signaling. Simultaneous inhibition of EGFR and IGF1R restored sensitivity to AMG510 in resistant cells. PI3K integrates signals from multiple RTKs and the level of phosphorylated AKT was revealed to negatively correlate with the anti-proliferative activity of AMG510 in KRASG12C-mutant cells. Concurrently treatment of a novel PI3Kα inhibitor CYH33 with AMG510 exhibited a synergistic effect against parental and resistant KRASG12C-mutant cells in vitro and in vivo, which was accompanied with concomitant inhibition of AKT and MAPK signaling. Taken together, these findings revealed the potential mechanism rendering acquired resistance to KRasG12C inhibitors and provided a mechanistic rationale to combine PI3Kα inhibitors with KRasG12C inhibitors for therapy of KRASG12C-mutant cancers in future clinical trials.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas p21(ras) , Receptores ErbB/efeitos dos fármacos , Receptores ErbB/metabolismo , Mutação , Fosfatidilinositol 3-Quinases/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/antagonistas & inibidores , Proteínas Proto-Oncogênicas p21(ras)/genética , Inibidores de Checkpoint Imunológico/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética
13.
Plant Cell ; 31(3): 602-626, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30755461

RESUMO

Wood remains the world's most abundant and renewable resource for timber and pulp and is an alternative to fossil fuels. Understanding the molecular regulation of wood formation can advance the engineering of wood for more efficient material and energy productions. We integrated a black cottonwood (Populus trichocarpa) wood-forming cell system with quantitative transcriptomics and chromatin binding assays to construct a transcriptional regulatory network (TRN) directed by a key transcription factor (TF), PtrSND1-B1 (secondary wall-associated NAC-domain protein). The network consists of four layers of TF-target gene interactions with quantitative regulatory effects, describing the specificity of how the regulation is transduced through these interactions to activate cell wall genes (effector genes) for wood formation. PtrSND1-B1 directs 57 TF-DNA interactions through 17 TFs transregulating 27 effector genes. Of the 57 interactions, 55 are novel. We tested 42 of these 57 interactions in 30 genotypes of transgenic P. trichocarpa and verified that ∼90% of the tested interactions function in vivo. The TRN reveals common transregulatory targets for distinct TFs, leading to the discovery of nine TF protein complexes (dimers and trimers) implicated in regulating the biosynthesis of specific types of lignin. Our work suggests that wood formation may involve regulatory homeostasis determined by combinations of TF-DNA and TF-TF (protein-protein) regulations.


Assuntos
Cromatina/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/genética , Redes Reguladoras de Genes/genética , Populus/genética , Fatores de Transcrição/metabolismo , Parede Celular/metabolismo , Cromatina/genética , Regulação da Expressão Gênica de Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Populus/crescimento & desenvolvimento , Populus/fisiologia , Fatores de Transcrição/genética , Madeira/crescimento & desenvolvimento
14.
Nanotechnology ; 33(16)2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-34986468

RESUMO

Construction of metal selenides with a large specific surface area and a hollow structure is one of the effective methods to improve the electrochemical performance of supercapacitors. However, the nano-material easily agglomerates due to the lack of support, resulting in the loss of electrochemical performance. Herein, we successfully design a three-dimensional graphene (3DG) encapsulation-protected hollow nanoboxes (CoSe2-SnSe2) composite aerogel (3DG/CoSe2-SnSe2) via a co-precipitation method coupled with self-assembly route, followed by a high temperature selenidation strategy. The obtained aerogel possesses porous 3DG conductive network, large specific surface area and plenty of reactive active sites. It could be used as a flexible and binder-free electrode after a facile mechanical compression process, which provided a high specific capacitance of 460 F g-1at 0.5 A g-1, good rate capability of 212.7 F g-1at 10 A g-1The capacitance retention rate is 80% at 2 A g-1after 5000 cycles due to the fast electron/ion transfer and electrolyte diffusion. With the as-prepared 3DG/CoSe2-SnSe2as positive electrodes and the AC (activated carbon) as negative electrodes, an asymmetric supercapacitor (3DG/CoSe2-SnSe2//AC) was fabricated, which delivered a high specific capacity of 38 F g-1at 1 A g-1and an energy density of 11.89 Wh kg-1at 749.9 W kg-1, as well as excellent cycle stability. This work provides a new method for preparing electrode material.

15.
Int J Mol Sci ; 23(21)2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36362276

RESUMO

Trauma is one of the most common conditions in the biomedical field. It is important to identify it quickly and accurately. However, when evanescent trauma occurs, it presents a great challenge to professionals. There are few reports on the establishment of a rapid and accurate trauma identification and prediction model. In this study, Fourier transform infrared spectroscopy (FTIR) and microscopic spectroscopy (micro-IR) combined with chemometrics were used to establish prediction models for the rapid identification of muscle trauma in humans and rats. The results of the average spectrum, principal component analysis (PCA) and loading maps showed that the differences between the rat muscle trauma group and the rat control group were mainly related to biological macromolecules, such as proteins, nucleic acids and carbohydrates. The differences between the human muscle trauma group and the human control group were mainly related to proteins, polysaccharides, phospholipids and phosphates. Then, a partial least squares discriminant analysis (PLS-DA) was used to evaluate the classification ability of the training and test datasets. The classification accuracies were 99.10% and 93.69%, respectively. Moreover, a trauma classification and recognition model of human muscle tissue was constructed, and a good classification effect was obtained. The classification accuracies were 99.52% and 91.95%. In conclusion, spectroscopy and stoichiometry have the advantages of being rapid, accurate and objective and of having high resolution and a strong recognition ability, and they are emerging strategies for the identification of evanescent trauma. In addition, the combination of spectroscopy and stoichiometry has great potential in the application of medicine and criminal law under practical conditions.


Assuntos
Quimiometria , Doenças Musculares , Humanos , Ratos , Animais , Análise Discriminante , Análise dos Mínimos Quadrados , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise de Componente Principal , Músculos
16.
Int J Legal Med ; 135(6): 2385-2394, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34173849

RESUMO

The identification of antemortem and postmortem fractures is a critical and challenging task for forensic researchers. Based on our preliminary studies, we explored whether the combination of Fourier transform infrared spectroscopy (FTIR) and chemometrics can identify antemortem and postmortem fractures in complex environments. The impacts of the four environments on the bone spectrum were analyzed by principal component analysis (PCA). It was found that the bone degradation rate in the submerged and ground surface (GS) environments was higher than that in the buried and constant temperature and moisture (CTM) environments. Additionally, the bone degradation rate in buried environment higher than that in the CTM environment. The average spectrum, PCA and partial least squares discriminant analysis (PLS-DA) results all revealed that there were significant differences between the antemortem fracture and the remaining three groups in a complex environment. Compared with the antemortem fracture, the antemortem fracture control (AFC) and postmortem fracture control (PFC) tended to be more similar to the postmortem fracture. According to the loading plot, amide I and amide II were the main components that contributed to the identification of the antemortem fracture, AFC, postmortem fracture, and PFC. Finally, we established a differential model for the antemortem and postmortem fractures (an accuracy of 96.9%), and a differentiation model for the antemortem fracture, AFC, postmortem fracture, and PFC (an accuracy of 87.5%). In conclusion, FTIR spectroscopy is a reliable tool for the identification of antemortem and postmortem fractures in complex environments.


Assuntos
Meio Ambiente , Modelos Teóricos , Tíbia/química , Fraturas da Tíbia , Animais , Restos Mortais/química , Masculino , Modelos Animais , Mudanças Depois da Morte , Análise de Componente Principal , Coelhos , Espectroscopia de Infravermelho com Transformada de Fourier
17.
J Chem Inf Model ; 61(5): 2499-2508, 2021 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-33938221

RESUMO

Enzyme activity is affected by amino acid mutations, particularly mutations near the active site. Increasing evidence has shown that distal mutations more than 10 Å away from the active site may significantly affect enzyme activity. However, it is difficult to study the enzyme regulation mechanism of distal mutations due to the lack of a systematic collection of three-dimensional (3D) structures, highlighting distal mutation site and the corresponding enzyme activity change. Therefore, we constructed a distal mutation database, namely, D3DistalMutation, which relates the distal mutation to enzyme activity. As a result, we observed that approximately 80% of distal mutations could affect enzyme activity and 72.7% of distal mutations would decrease or abolish enzyme activity in D3DistalMutation. Only 6.6% of distal mutations in D3DistalMutation could increase enzyme activity, which have great potential to the industrial field. Among these mutations, the Y to F, S to D, and T to D mutations are most likely to increase enzyme activity, which sheds some light on industrial catalysis. Distal mutations decreasing enzyme activity in the allosteric pocket play an indispensable role in allosteric drug design. In addition, the pockets in the enzyme structures are provided to explore the enzyme regulation mechanism of distal mutations. D3DistalMutation is accessible free of charge at https://www.d3pharma.com/D3DistalMutation/index.php.


Assuntos
Domínio Catalítico , Catálise , Mutação
18.
BMC Surg ; 21(1): 284, 2021 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-34090388

RESUMO

BACKGROUND: Full-thickness rectal prolapse (FTRP) frequently occurs in elderly women, and more than 100 surgical procedures have been proposed to restore FTRP. The Gant-Miwa-Thiersch (GMT) procedure is the most used treatment in China. However, the recurrence rate of FTRP post-GMT, which is as high as 23.8%, is concerning. We described a new modified GMT combined with internal and external rectal sclerosant injection (nmGMTSI) procedure to address this problem. METHODS: The nmGMTSI was performed under spinal anesthesia in 34 frail, elderly female patients with FTRP. The surgical results of FTRP were assessed. Fecal incontinence and constipation were evaluated using the Wexner score, and anal canal rest pressure (ACRP), maximum anal systolic pressure (MASP), anorectal sensation thresholds (AST), and maximum rectal tolerance (MRT) using anorectal manometry preoperatively and postoperatively. The causes of recurrence and complications were analyzed. RESULTS: All patients were cured according to the clinical cure standard. The perioperative Wexner fecal incontinence score (WFIS) was 10.3 ± 3.31, which became 3.7 ± 2.43 (P < 0.0001) postoperatively. The perioperative ACRP was 2.0 ± 0.56 kPa, which became 8.5 ± 2.25 kPa (P < 0.0001) postoperatively. The perioperative MASP was 4.5 ± 1.16 kPa, which became 18.6 ± 2.50 kPa (P < 0.0001) postoperatively. However, no significant difference was observed between the preoperative and postoperative Wexner constipation scores (WCS) (17.3 ± 2.25 vs. 15.4 ± 2.89, P = 0.1047). The perioperative and postoperative AST were 38.1 ± 5.34 mL and 23.5 ± 3.61 mL, respectively (P = 0.0002). The maximum rectal tolerance (MRT) was 157.1 ± 16.73 mL, which became 121.2 ± 12.45 mL postoperatively (P = 0.0009). The patients developed no serious postoperative complications. The total relapse rate after nmGMTSI was 2.9% in the median two years follow-up period. The most common cause of relapse after nmGMTSI was the removal of infected threads used in the Thiersch procedure. CONCLUSION: The benefits of nmGMTSI include low rates of recurrence, complications, and mortality, cost-effectiveness, wide adaptation, minimal invasiveness, and technical simplicity. Hence, it should be considered the first option for the treatment of FTRP in frail elderly women.


Assuntos
Prolapso Retal , Soluções Esclerosantes , Idoso , China , Feminino , Humanos , Prolapso Retal/cirurgia , Reto/cirurgia , Escleroterapia
19.
J Chem Phys ; 153(9): 094109, 2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32891107

RESUMO

Protein conformational changes are activated processes essential for protein functions. Activation in a protein differs from activation in a small molecule in that it involves directed and systematic energy flows through preferred channels encoded in the protein structure. Understanding the nature of these energy flow channels and how energy flows through them during activation is critical for understanding protein conformational changes. We recently [W. Li and A. Ma, J. Chem. Phys. 144, 114103 (2016)] developed a rigorous statistical mechanical framework for understanding potential energy flows. Here, we complete this theoretical framework with a rigorous theory for kinetic energy flows: potential and kinetic energies interconvert when impressed forces oppose inertial forces, whereas kinetic energy transfers directly from one coordinate to another when inertial forces oppose each other. This theory is applied to analyzing a prototypic system for biomolecular conformational dynamics: the isomerization of an alanine dipeptide. Among the two essential energy flow channels for this process, dihedral ϕ confronts the activation barrier, whereas dihedral θ1 receives energy from potential energy flows. Intriguingly, θ1 helps ϕ to cross the activation barrier by transferring to ϕ via direct kinetic energy flow all the energy it received-an increase in θ̇1 caused by potential energy flow converts into an increase in ϕ̇. As a compensation, θ1 receives kinetic energy from bond angle α via a direct mechanism and bond angle ß via an indirect mechanism.


Assuntos
Fenômenos Mecânicos , Proteínas/metabolismo , Fenômenos Biomecânicos , Cinética , Modelos Moleculares
20.
Proc Natl Acad Sci U S A ; 114(45): E9722-E9729, 2017 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-29078399

RESUMO

Secondary cell wall (SCW) biosynthesis is the biological process that generates wood, an important renewable feedstock for materials and energy. NAC domain transcription factors, particularly Vascular-Related NAC-Domain (VND) and Secondary Wall-Associated NAC Domain (SND) proteins, are known to regulate SCW differentiation. The regulation of VND and SND is important to maintain homeostasis for plants to avoid abnormal growth and development. We previously identified a splice variant, PtrSND1-A2IR , derived from PtrSND1-A2 as a dominant-negative regulator, which suppresses the transactivation of all PtrSND1 family members. PtrSND1-A2IR also suppresses the self-activation of the PtrSND1 family members except for its cognate transcription factor, PtrSND1-A2, suggesting the existence of an unknown factor needed to regulate PtrSND1-A2 Here, a splice variant, PtrVND6-C1IR , derived from PtrVND6-C1 was discovered that suppresses the protein functions of all PtrVND6 family members. PtrVND6-C1IR also suppresses the expression of all PtrSND1 members, including PtrSND1-A2, demonstrating that PtrVND6-C1IR is the previously unidentified regulator of PtrSND1-A2 We also found that PtrVND6-C1IR cannot suppress the expression of its cognate transcription factor, PtrVND6-C1PtrVND6-C1 is suppressed by PtrSND1-A2IR Both PtrVND6-C1IR and PtrSND1-A2IR cannot suppress their cognate transcription factors but can suppress all members of the other family. The results indicate that the splice variants from the PtrVND6 and PtrSND1 family may exert reciprocal cross-regulation for complete transcriptional regulation of these two families in wood formation. This reciprocal cross-regulation between families suggests a general mechanism among NAC domain proteins and likely other transcription factors, where intron-retained splice variants provide an additional level of regulation.


Assuntos
Regulação da Expressão Gênica de Plantas/genética , Genes de Plantas , Família Multigênica , Populus/genética , Fatores de Transcrição/genética , Madeira/crescimento & desenvolvimento , Madeira/genética , Xilema/genética , Processamento Alternativo , Parede Celular/genética , Parede Celular/metabolismo , Clonagem Molecular , DNA de Plantas , Redes Reguladoras de Genes , Homeostase , Proteínas Nucleares , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Brotos de Planta/genética , Brotos de Planta/metabolismo , Populus/metabolismo , Proteínas Recombinantes/genética , Fatores de Transcrição/metabolismo , Ativação Transcricional/genética , Transcriptoma , Xilema/crescimento & desenvolvimento
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