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Water use efficiency (WUE) is crucial for apple tree fitness and survival, especially in response to climatic changes. The receptor-like kinase FERONIA is reportedly an essential regulator of plant stress responses, but its role in regulating WUE under water deficit conditions is unclear. Here, we found that overexpressing the apple FERONIA receptor kinase gene, MdMRLK2, enhanced apple WUE under long-term water deficit conditions. Under drought treatment, 35S::MdMRLK2 apple plants exhibited higher photosynthetic capacity and antioxidant enzyme activities than wild-type (WT) plants. 35S::MdMRLK2 apple plants also showed increased biomass accumulation, root activity, and water potential compared to WT plants. Moreover, MdMRLK2 physically interacts with and phosphorylates cinnamoyl-CoA reductase 1, MdCCR1, an enzyme essential for lignin synthesis, at position Ser260. This interaction likely contributed to increased vessel density, vascular cylinder area, and lignin content in 35S::MdMRLK2 apple plants under drought conditions. Therefore, our findings reveal a novel function of MdMRLK2 in regulating apple WUE under water deficit conditions.
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Cold is one of the main abiotic stresses in temperate fruit crops, affecting the yield and fruit quality of apple in China and European countries. The plant receptor-like kinase FERONIA is widely reported to be involved in abiotic stresses. However, its function in apple cold resistance remains unknown. Modification of cell wall components and accumulation of soluble sugars and amino acids are important strategies by which plants cope with cold. In this study, expression of the apple FERONIA receptor-like kinase gene MdMRLK2 was rapidly induced by cold. Apple plants overexpressing MdMRLK2 (35S:MdMRLK2) showed enhanced cold resistance relative to the wild type. Under cold conditions, 35S:MdMRLK2 apple plants had higher amounts of water insoluble pectin, lignin, cellulose, and hemicellulose, which may have resulted from reduced activities of polygalacturonase, pectinate lyase, pectinesterase, and cellulase. More soluble sugars and free amino acids and less photosystem damage were also observed in 35S:MdMRLK2 apple plants. Intriguingly, MdMRLK2 interacted with the transcription factor MdMYBPA1 and promoted its binding to MdANS and MdUFGT promoters, leading to more anthocyanin biosynthesis, particularly under cold conditions. These findings complemented the function of apple FERONIA MdMRLK2 responding to cold resistance.
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Malus , Malus/metabolismo , Proteínas de Plantas/metabolismo , Frutas/genética , Frutas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , China , Regulação da Expressão Gênica de Plantas , Temperatura BaixaRESUMO
BACKGROUND: Stroke often damages the basal ganglia, leading to atypical and transient aphasia, indicating that post-stroke basal ganglia aphasia (PSBGA) may be related to different anatomical structural damage and functional remodeling rehabilitation mechanisms. The basal ganglia contain dense white matter tracts (WMTs). Hence, damage to the functional tract may be an essential anatomical structural basis for the development of PSBGA. METHODS: We first analyzed the clinical characteristics of PSBGA in 28 patients and 15 healthy controls (HCs) using the Western Aphasia Battery and neuropsychological test batteries. Moreover, we investigated white matter injury during the acute stage using diffusion magnetic resonance imaging scans for differential tractography. Finally, we used multiple regression models in correlation tractography to analyze the relationship between various language functions and quantitative anisotropy (QA) of WMTs. RESULTS: Compared with HCs, patients with PSBGA showed lower scores for fluency, comprehension (auditory word recognition and sequential commands), naming (object naming and word fluency), reading comprehension of sentences, Mini-Mental State Examination, and Montreal Cognitive Assessment, along with increased scores in Hamilton Anxiety Scale-17 and Hamilton Depression Scale-17 within 7 days after stroke onset (P < 0.05). Differential tractography revealed that patients with PSBGA had damaged fibers, including in the body fibers of the corpus callosum, left cingulum bundles, left parietal aslant tracts, bilateral superior longitudinal fasciculus II, bilateral thalamic radiation tracts, left fornix, corpus callosum tapetum, and forceps major, compared with HCs (FDR < 0.02). Correlation tractography highlighted that better comprehension was correlated with a higher QA of the left inferior fronto-occipital fasciculus (IFOF), corpus callosum forceps minor, and left extreme capsule (FDR < 0.0083). Naming was positively associated with the QA of the left IFOF, forceps minor, left arcuate fasciculus, and uncinate fasciculus (UF) (FDR < 0.0083). Word fluency of naming was also positively associated with the QA of the forceps minor, left IFOF, and thalamic radiation tracts (FDR < 0.0083). Furthermore, reading was positively correlated with the QA of the forceps minor, left IFOF, and UF (FDR < 0.0083). CONCLUSION: PSBGA is primarily characterized by significantly impaired word fluency of naming and preserved repetition abilities, as well as emotional and cognitive dysfunction. Damaged limbic pathways, dorsally located tracts in the left hemisphere, and left basal ganglia pathways are involved in PSBGA pathogenesis. The results of connectometry analysis further refine the current functional localization model of higher-order neural networks associated with language functions.
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Afasia , Gânglios da Base , Imagem de Tensor de Difusão , Acidente Vascular Cerebral , Substância Branca , Humanos , Masculino , Feminino , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Pessoa de Meia-Idade , Idoso , Imagem de Tensor de Difusão/métodos , Gânglios da Base/diagnóstico por imagem , Gânglios da Base/patologia , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/patologia , Afasia/diagnóstico por imagem , Afasia/etiologia , Afasia/fisiopatologia , Afasia/patologia , Idioma , Adulto , Imagem de Difusão por Ressonância MagnéticaRESUMO
Fusarium spp., a necrotrophic soil-borne pathogen, causes root rot disease on many crops. CERK1, as a typical pattern recognition receptor, has been widely studied. However, the function of CERK1 during plant-Fusarium interaction has not been well described. We determined that MdCERK1 is a susceptibility gene in the apple-Fusarium solani (Fs) interaction, and jasmonic acid (JA) plays a crucial role in this process. MdCERK1 directly targets and phosphorylates the lipoxygenase MdLOX2.1, an enzyme initiating the JA biosynthesis, at positions Ser326 and Thr327. These phosphorylations inhibit its translocation from the cytosol to the chloroplasts, leading to a compromised JA biosynthesis. Fs upregulates MdCERK1 expression during infection. In turn, when the JA level is low, the apple MdWRKY71, a transcriptional repressor of MdCERK1, is markedly upregulated and phosphorylated at Thr99 and Thr102 residues by the MAP kinase MdMMK2. The phosphorylation of MdWRKY71 enhances its transcription inhibition on MdCERK1. Taken together, MdCERK1 plays a novel role in limiting JA biosynthesis. There seems to be an arms race between apple and Fs, in which Fs activates MdCERK1 expression to reduce the JA level, while apple senses the low JA level and activates the MdMMK2-MdWRKY71 module to elevate JA level by inhibiting MdCERK1 expression.
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Ciclopentanos , Fusarium , Regulação da Expressão Gênica de Plantas , Malus , Oxilipinas , Doenças das Plantas , Proteínas de Plantas , Ciclopentanos/metabolismo , Oxilipinas/metabolismo , Malus/microbiologia , Malus/genética , Malus/metabolismo , Fusarium/fisiologia , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Doenças das Plantas/microbiologia , Retroalimentação Fisiológica , Resistência à Doença/genética , Fosforilação , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genéticaRESUMO
Lymphatic system distributes in almost all vertebrate tissues and organs, and plays important roles in the regulation of body fluid balance, lipid absorption and immune monitoring. Although CuNPs or AgNPs accumulation has been reported to be closely associated with delayed hatching and motor dysfunction in zebrafish embryos, their biological effects on lymphangiogenesis remain unknown. In this study, thoracic duct was observed to be partially absent in both CuNPs and AgNPs stressed zebrafish larvae. Specifically, CuNPs stress induced hypermethylation of E2F7/8 binding sites on CCBE1 promoters via their producing ROS, thereby leading to the reduction of binding enrichment of E2F7/8 on CCBE1 promoter and its subsequently reduced expression, then resulting in defective lymphatic vessel formation. Differently, AgNPs stress induced down-regulated CCBE1 expression via down-regulating mRNA and protein levels of E2F7/8 transcription factors, thereby resulting in defective lymphatic vessel formation. This study may be the first to demonstrate that CuNPs and AgNPs damaged lymphangiogenesis during zebrafish embryogenesis, mechanistically, CuNPs epigenetically regulated the expression of lymphangiogenesis regulator CCBE1 via hypermethylating its promoter binding sites of E2F7/8, while AgNPs via regulating E2F7/8 expression. Meanwhile, overexpression of ccbe1 mRNA effectively rescued the lymphangiogenesis defects in both AgNPs and CuNPs stressed larvae, while overexpression of e2f7/8 mRNA effectively rescued the lymphangiogenesis defects in AgNPs rather than CuNPs stressed larvae. The results in this study will shed some light on the safety assessment of nanomaterials applied in medicine and on the ecological security assessments of nanomaterials. Video Abstract.
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Nanopartículas Metálicas , Peixe-Zebra , Animais , Peixe-Zebra/metabolismo , Linfangiogênese/genética , Cobre/química , Prata/farmacologia , Prata/química , Prata/metabolismo , RNA Mensageiro/metabolismoRESUMO
As part of the central nervous system (CNS), the retina senses light and also conducts and processes visual impulses. The damaged development of the retina not only causes visual damage, but also leads to epilepsy, dementia and other brain diseases. Recently, we have reported that copper (Cu) overload induces retinal developmental defects and down-regulates microtubule (MT) genes during zebrafish embryogenesis, but whether the down-regulation of microtubule genes mediates Cu stress induced retinal developmental defects is still unknown. In this study, we found that microtubule gene stmn4 exhibited obviously reduced expression in the retina of Cu overload embryos. Furthermore, stmn4 deficiency (stmn4-/-) resulted in retinal defects similar to those seen in Cu overload embryos, while overexpression of stmn4 effectively rescued retinal defects and cell apoptosis occurred in the Cu overload embryos and larvae. Meanwhile, stmn4 deficient embryos and larvae exhibited reduced mature retinal cells, the down-regulated expression of microtubules and cell cycle-related genes, and the mitotic cell cycle arrests of the retinal cells, which subsequently tended to apoptosis independent on p53. The results of this study demonstrate that Cu stress might lead to retinal developmental defects via down-regulating expression of microtubule gene stmn4, and stmn4 deficiency leads to impaired cell cycle and the accumulation of retinal progenitor cells (RPCs) and their subsequent apoptosis. The study provides a certain referee for copper overload in regulating the retinal development in fish.
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Cobre , Retina , Estatmina , Peixe-Zebra , Animais , Apoptose/genética , Ciclo Celular , Cobre/efeitos adversos , Larva , Retina/patologia , Peixe-Zebra/genética , Estatmina/genética , Proteínas de Peixe-Zebra/genéticaRESUMO
With the rapid development of society, it is of paramount importance to expeditiously assess environmental pollution and provide early warning of toxicity risks. Microbial fuel cell-based self-powered biosensors (MFC-SPBs) have emerged as a pivotal technology, obviating the necessity for external power sources and aligning with the prevailing trends toward miniaturization and simplification in biosensor development. In this case, vigorous advancements in MFC-SPBs have been acquired in past years, irrespective of whether the target identification event transpires at the anode or cathode. The present article undertakes a comprehensive review of developed MFC-SPBs, categorizing them into substrate effect and microbial activity effect based on the nature of the target identification event. Furthermore, various enhancement strategies to improve the analytical performance like accuracy and sensitivity are also outlined, along with a discussion of future research trends and application prospects of MFC-SPBs for their better developments.
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Fontes de Energia Bioelétrica , Técnicas Biossensoriais , Eletrodos , Técnicas Biossensoriais/métodos , Técnicas Biossensoriais/instrumentaçãoRESUMO
BACKGROUND: Neutrophil percentage-to-albumin ratio (NPAR) was significantly correlated with diabetes-related complications. There are little data about NPAR and mortality risk in individuals with diabetes. METHODS: This study included 3858 diabetes patients from the National Health and Nutrition Examination Survey (NHANES) conducted from 1988 to 2018. Using a restricted cubic spline (RCS), the relationship between the NPAR and mortality risk was shown. Multivariable Cox regression models were used to evaluate the relationship between the NPAR and diabetes-cause and all-cause death. An examination of the time-dependent receiver operating characteristic curve (ROC) was used to assess how well the NPAR predicted survival outcomes. RESULTS: Among 3858 diabetes individuals, a total of 1198 (31.1%) died over a mean follow-up of 7.86 years; of these, 326 (8.4%) had diabetes-related deaths and 872 (22.6%) had deaths from other causes. The RCS regression analysis showed a positive linear association between the NPAR and all-cause and diabetes-cause mortality. High NPAR group had a significantly higher risk of all-cause and diabetes-cause mortality in univariate and multivariate analysis. Compared with low NPAR group, high NPAR group had a low survival rate of diabetes cases in all-cause death and diabetes-cause mortality with area under the curve of the 3-, 5-, and 10-year ROC curve being 0.725, 0.739, and 0.734 for all-cause mortality and 0.754, 0.752, and 0.745 for diabetes-cause mortality, respectively. CONCLUSION: In summary, we examined 3858 diabetes patients from NHANES database (1998-2018) and suggested NPAR as a biomarker for all-cause and diabetes-cause mortality prediction.
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This study systematically combed the randomized controlled trial(RCT) of Chinese patent medicines in treatment of type 2 diabetes mellitus(T2DM) in recent five years by using the method of evidence map. It understood the distribution and quality of evidence in this field and found the existing Chinese patent medicines in treatment of T2DM and the problems in its research. The study collected the commonly used Chinese patent medicines for the treatment of T2DM from three drug catalogs, retrieved Chinese and English databases to obtain RCT literature related to Chinese patent medicines in recent five years, and extracted information such as sample size, study drug, combination medication, course of treatment, and outcome indicators from the literature. It also conducted quality evaluation based on the Cochrane collaborative network bias risk assessment tool and used charts to display the analysis results. A total of 19 kinds of Chinese patent medicines are collected, of which 13 kinds of Chinese patent medicines are mentioned in 131 articles related to RCT. The literature concerning Shenqi Jiangtang Capsules/Granules, Jinlida Granules, and Xiaoke Pills accounts for a large proportion. Outcome indicators include blood glucose, blood lipids, pancreatic islet cell function, and clinical symptoms. In terms of literature quality, 75 articles have correct random methods, and 1 article performs allocation hiding and blind methods. Therefore, the clinical orientation of Chinese patent medicines for the treatment of T2DM is broad, failing to reflect their own characteristics and lacking safety information. Insufficient attention has been paid to TCM syndrome scores, quality of life, and blood lipid outcome indicators that reflect the characteristics of traditional Chinese medicine(TCM). The number of studies on the treatment of T2DM by Chinese patent medicines varies greatly among varieties, and the quality of the studies is low. It is suggested that the holders of the marketing license of T2DM Chinese patent medicines should carry out a post-marketing re-evaluation of the varieties of traditional Chinese patent medicines for treating T2DM according to the relevant requirements of the State Food and Drug Administration, standardize the clinical positioning, and revise and improve the safety information in the instructions. It is recommended that researchers construct a core indicator dataset for Chinese patent medicine treatment of T2DM, improve the efficacy evaluation system, and develop an experimental plan based on CONSORT before conducting RCT.
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Diabetes Mellitus Tipo 2 , Medicamentos de Ervas Chinesas , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Medicamentos de Ervas Chinesas/efeitos adversos , Medicina Tradicional Chinesa , Medicamentos sem Prescrição/uso terapêutico , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
Human leukocyte antigen (HLA) plays a vital role in immunomodulatory function. Studies have shown that immunotherapy based on non-classical HLA has essential applications in cancer, COVID-19, and allergic diseases. However, there are few deep learning methods to predict non-classical HLA alleles. In this work, an adaptive dual-attention network named DapNet-HLA is established based on existing datasets. Firstly, amino acid sequences are transformed into digital vectors by looking up the table. To overcome the feature sparsity problem caused by unique one-hot encoding, the fused word embedding method is used to map each amino acid to a low-dimensional word vector optimized with the training of the classifier. Then, we use the GCB (group convolution block), SENet attention (squeeze-and-excitation networks), BiLSTM (bidirectional long short-term memory network), and Bahdanau attention mechanism to construct the classifier. The use of SENet can make the weight of the effective feature map high, so that the model can be trained to achieve better results. Attention mechanism is an Encoder-Decoder model used to improve the effectiveness of RNN, LSTM or GRU (gated recurrent neural network). The ablation experiment shows that DapNet-HLA has the best adaptability for five datasets. On the five test datasets, the ACC index and MCC index of DapNet-HLA are 4.89% and 0.0933 higher than the comparison method, respectively. According to the ROC curve and PR curve verified by the 5-fold cross-validation, the AUC value of each fold has a slight fluctuation, which proves the robustness of the DapNet-HLA. The codes and datasets are accessible at https://github.com/JYY625/DapNet-HLA.
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COVID-19 , Aprendizado Profundo , Humanos , Antígenos de Histocompatibilidade Classe I/metabolismo , Antígenos HLA , Sítios de LigaçãoRESUMO
A self-powered ultraviolet (UV) photodetector (PD) with a position-controlled array based on zinc oxide (ZnO) nanoclusters (NCs) has been proposed. The structure of the special array makes it possible to reduce the light loss and improve the light trap. The PD innovatively modifies the structure of ZnO PDs, which is distinguished from other traditional devices. The results demonstrate that the ZnO NC array can spontaneously generate the carrier and successfully achieve the detection at zero bias under the radiation of UV light. In this study, the structure is fabricated with two different substrates of silicon (Si) and GaN. At zero bias voltage, the Si-based PD under 365 nm shows the responsivity and external quantum efficiency (EQE) reaching up to 14.1 mA/W and 4.79%, respectively, and the responsivity of the GaN-based detector can be obtained up to 59.9 mA/W; its parameter of EQE is 20.04%, the photocurrent is 10-5A, and the on/off ratio is 174. Our findings indicate that this structure of the device has potential for applications that require detection of light.
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PURPOSE: To investigate the risk factors for residual dizziness (RD) in patients with benign paroxysmal positional vertigo (BPPV) after successful repositioning. METHODS: Searches were performed in PubMed, Embase, Cochrane library, Web of Science, Chinese National Knowledge Infrastructure, and Sino Med up to March 7, 2021 and references of relevant articles were screened. Data from eligible studies were meta-analyzed using Stata version 16.0 and Review Manager 5.4. RESULTS: In this systematic review and meta-analysis of 4487 patients from 31 studies, the prevalence of RD was 43.0% (95% CI 39.0-48.0%). Age (MD 4.17; 95% CI 2.13-6.21, P = 0.000), female gender (OR = 1.28, 95% CI 1.11-1.47, P = 0.001), secondary BPPV (OR 1.88; 95% CI 1.27-2.77, P = 0.001), a longer duration of BPPV before treatment (MD 3.45; 95% CI 1.87-5.02, P = 0.000), abnormal ocular vestibular evoked myogenic potential (OVEMP, OR 4.34; 95% CI 2.78-6.78, P = 0.000), abnormal cervical vestibular evoked myogenic potential (CVEMP, OR 2.48; 95% CI 1.54-3.99, P = 0.000), higher Dizziness Handicap Index (DHI) score before treatment (MD 10.88; 95% CI 5.96-15.80, P = 0.000), anxiety (OR 9.58; 95% CI 6.32-14.52, P = 0.000), osteopenia (OR = 4.40, 95% CI 2.17-8.96, P = 0.000), onset in winter (OR 7.27; 95% CI 2.38-22.24, P = 0.001) and with a history of BPPV (OR 1.79; 95% CI 1.06-3.04, P = 0.03) are the risk factors for RD in patients with BPPV after successful repositioning. The affected side, location or type of semicircular involvement, hyperlipidemia, diabetes, hypertension, heart disease, migraine, sleep disorders, canalolithiasis/cupulolithiasis, the number of times the canalith repositioning procedures (CRPs) were performed and number of vertigo attacks did not correlate with the occurrence of RD. CONCLUSIONS: Despite successful treatment, nearly half of the BPPV patients developed RD. RD seems to be a syndrome caused by multiple factors. The pathogenesis of most factors can be explained by psychological and/or physical disorders. Early recognition of these risk factors contributes to the prevention and treatment of RD.
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Transtornos de Enxaqueca , Potenciais Evocados Miogênicos Vestibulares , Vertigem Posicional Paroxística Benigna/epidemiologia , Vertigem Posicional Paroxística Benigna/etiologia , Vertigem Posicional Paroxística Benigna/terapia , Progressão da Doença , Tontura , Feminino , Humanos , Posicionamento do Paciente , Fatores de Risco , Potenciais Evocados Miogênicos Vestibulares/fisiologiaRESUMO
Introduction: The coexistence of hepatitis B virus (HBV) and hepatitis B surface antibodies (anti-HBs) in occult hepatitis B virus infection (OBI) is a contradictory phenomenon, and the underlying mechanism is not fully understood. The characteristics of pre-S/S mutations in OBI genotypes B and C (OBIB and OBIC) in the presence or absence of anti-HBs were analyzed extensively in this study. Methodology. The amino acid substitutions of envelope proteins of 21 OBI strains, including 4 HBs (+) OBIB, 6 HBs (-) OBIB, 6 HBs (+) OBIc, and 5 HBs (-) OBIC samples, were analyzed and fully compared among groups of HBV genotypes and the presence of anti-HBs. Results: The mutation rates in pre-S1, pre-S2, and S proteins of OBIC were significantly higher than wild-type HBV (wt-HBV) genotype C strains, but only the mutation rate of S protein in OBIB was significantly higher compared to wild-type HBV genotype B. The mutation rates in S protein of anti-HBs (-) OBI were higher than anti-HBs(+) OBI samples (4.40% vs. 2.43% in genotype B, P > 0.05; 6.81% vs. 3.47% in genotype C, P < 0.05). For these high-frequency substitutions in the pre-S/S region, the mutations sN40S and sK122R were found in 27.3% and 45.5% of anti-HBs (-) OBI strains, respectively. 7 substitutions were uniquely found in OBIC strains and 9 substitutions were commonly detected in OBIB and OBIC strains. Conclusions: These results suggested that the mutations might occur randomly and were not selected by antibody pressure.
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OBJECTIVE: To analyze the factors affecting the long-term prognosis of tinnitus accompanied by unilateral idiopathic sudden sensorineural hearing loss (SSNHL). METHODS: A total of 161 patients with sudden hearing loss (HL) accompanied by tinnitus were enrolled. All patients had two separate telephone follow-ups and were asked about changes in tinnitus. The severity of tinnitus at admission and the outcome at discharge were assessed in terms of the patients' sex, age, level of HL, type of audiogram, etc. Results: The prognosis of tinnitus after SSNHL had no relationship with grades of HL or hearing recovery. Initial tinnitus level was remarkably associated with tinnitus improvement at discharge and was an independent risk factor for the long-term prognosis of residual tinnitus after SSNHL (odds ratio 0.722, 95% confidence interval 0.550-0.949, p = 0.019), and the median recovery time was 23.00 ± 3.80 months. CONCLUSIONS: Residual tinnitus after SSNHL has a tendency of self-recovery. The short-term prognosis of tinnitus may be related to psychological changes caused by hearing recovery, while the long-term prognosis of residual tinnitus after SSNHL is related only to the initial tinnitus level, with a median recovery time of approximately 2 years.
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Perda Auditiva Neurossensorial , Perda Auditiva Súbita , Zumbido , Perda Auditiva Neurossensorial/complicações , Perda Auditiva Súbita/complicações , Humanos , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Zumbido/complicaçõesRESUMO
INTRODUCTION: Small open reading frames (sORFs) with potential protein-coding capacity have been disclosed in various transcripts, including long noncoding RNAs (LncRNAs), mRNAs (5'-upstream, coding domain, and 3'-downstream), circular RNAs, pri-miRNAs, and ribosomal RNAs (rRNAs). Recent characterization of several sORF-encoded peptides (SEPs or micropeptides) revealed their important roles in many fundamental biological processes in a broad range of species from yeast to human. The success in the mining of micropeptides attributes to the advanced bioinformatics and high-throughput sequencing techniques. Areas covered: sORFs and SEPs were overlooked for their tiny size and the difficulty of identification by bioinformatics analyses. With more and more sORFs and SEPs have been identified, this field has attracted more attention. This review covers recent advances in the strategies for the detection and identification of sORFs and SEPs. Expert commentary: The advantages and drawbacks of the strategies for detection and identification of sORFs and SEPs are discussed, as well as the techniques that are used to decipher the roles of micropeptides in organisms are described.
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Fases de Leitura Aberta/genética , Peptídeos/genética , Proteômica , Biologia Computacional , Humanos , RNA Circular/genética , RNA Longo não Codificante/genética , RNA Mensageiro/genética , RNA Ribossômico/genéticaRESUMO
The hydrogenation of ethyl acetate to ethanol catalyzed by SNS pincer ruthenium complexes was computationally investigated by using DFT. Different from a previously proposed mechanism with fac-[(SNS)Ru(PPh3 )(H)2 ] (5') as the catalyst, an unexpected direct hydride transfer mechanism with a mer-SNS ruthenium complex as the catalyst, and two cascade catalytic cycles for hydrogenations of ethyl acetate to aldehyde and aldehyde to ethanol, is proposed base on our calculations. The new mechanism features ethanol-assisted proton transfer for H2 cleavage, direct hydride transfer from ruthenium to the carbonyl carbon, and C-OEt bond cleavage. Calculation results indicate that the rate-determining step in the whole catalytic reaction is the transfer of a hydride from ruthenium to the carbonyl carbon of ethyl acetate, with a total free energy barrier of only 26.9â kcal mol-1 , which is consistent with experimental observations and significantly lower than the relative free energy of an intermediate in a previously postulated mechanism with 5' as the catalyst.
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Inspired by the active-site structure of the [NiFe] hydrogenase, we have computationally designed the iron complex [P(tBu) 2 N(tBu) 2 )Fe(CN)2 CO] by using an experimentally ready-made diphosphine ligand with pendant amines for the hydrogenation of CO2 to methanol. Density functional theory calculations indicate that the rate-determining step in the whole catalytic reaction is the direct hydride transfer from the Fe center to the carbon atom in the formic acid with a total free energy barrier of 28.4â kcal mol(-1) in aqueous solution. Such a barrier indicates that the designed iron complex is a promising low-cost catalyst for the formation of methanol from CO2 and H2 under mild conditions. The key role of the diphosphine ligand with pendent amine groups in the reaction is the assistance of the cleavage of H2 by forming a Fe-H(δ-) â â â H(δ+) -N dihydrogen bond in a fashion of frustrated Lewis pairs.
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Aminas/química , Dióxido de Carbono/química , Complexos de Coordenação/química , Ferro/química , Metanol/química , Catálise , Domínio Catalítico , Formiatos/química , Hidrogênio/química , Hidrogenase/química , Hidrogenase/metabolismo , Hidrogenação , Conformação Molecular , Fosfinas/química , TermodinâmicaRESUMO
A series of cobalt complexes with acylmethylpyridinol and aliphatic PNP pincer ligands are proposed based on the active site structure of [Fe]-hydrogenase. Density functional theory calculations indicate that the total free energy barriers of the hydrogenation of CO2 and dehydrogenation of formic acid catalyzed by these Co complexes are as low as 23.1 kcal/mol in water. The acylmethylpyridinol ligand plays a significant role in the cleavage of H2 by forming a strong Co-Hδ-···Hδ+-O dihydrogen bond in a fashion of frustrated Lewis pairs.
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By combining molecule dynamics (MD) simulation and quantum chemistry computation, we calculate the surface sum-frequency vibrational spectroscopy (SFVS) of R-limonene molecules at the gas-liquid interface for SSP, PPP, and SPS polarization combinations. The distributions of the Euler angles are obtained using MD simulation, the ψ-distribution is between isotropic and Gaussian. Instead of the MD distributions, different analytical distributions such as the δ-function, Gaussian and isotropic distributions are applied to simulate surface SFVS. We find that different distributions significantly affect the absolute SFVS intensity and also influence on relative SFVS intensity, and the δ-function distribution should be used with caution when the orientation distribution is broad. Furthermore, the reason that the SPS signal is weak in reflected arrangement is discussed.
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Cicloexenos/química , Simulação de Dinâmica Molecular , Análise Espectral , Terpenos/química , Algoritmos , Gases/química , Limoneno , Propriedades de Superfície , VibraçãoRESUMO
BACKGROUND: The novel coronavirus pneumonia (COVID-19) outbreak in late 2019 killed millions worldwide. Coronaviruses cause diseases such as severe acute respiratory syndrome (SARS-Cov) and SARS-COV-2. Many peptides in the host defense system have antiviral activity. How to establish a set of efficient models to identify anti-coronavirus peptides is a meaningful study. METHODS: Given this, a new prediction model EACVP is proposed. This model uses the evolutionary scale language model (ESM-2 LM) to characterize peptide sequence information. The ESM model is a natural language processing model trained by machine learning technology. It is trained on a highly diverse and dense dataset (UR50/D 2021_04) and uses the pre-trained language model to obtain peptide sequence features with 320 dimensions. Compared with traditional feature extraction methods, the information represented by ESM-2 LM is more comprehensive and stable. Then, the features are input into the convolutional neural network (CNN), and the convolutional block attention module (CBAM) lightweight attention module is used to perform attention operations on CNN in space dimension and channel dimension. To verify the rationality of the model structure, we performed ablation experiments on the benchmark and independent test datasets. We compared the EACVP with existing methods on the independent test dataset. RESULTS: Experimental results show that ACC, F1-score, and MCC are 3.95%, 35.65% and 0.0725 higher than the most advanced methods, respectively. At the same time, we tested EACVP on ENNAVIA-C and ENNAVIA-D data sets, and the results showed that EACVP has good migration and is a powerful tool for predicting anti-coronavirus peptides. CONCLUSION: The results prove that this model EACVP could fully characterize the peptide information and achieve high prediction accuracy. It can be generalized to different data sets. The data and code of the article have been uploaded to https://github.- com/JYY625/EACVP.git.