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Precise control over how and where actin filaments are created leads to the construction of unique cytoskeletal arrays within a common cytoplasm. Actin filament nucleators are key players in this activity and include the conserved actin-related protein 2/3 (Arp2/3) complex as well as a large family of formins. In some eukaryotic cells, these nucleators compete for a common pool of actin monomers and loss of one favors the activity of the other. To test whether this mechanism is conserved, we combined the ability to image single filament dynamics in the homeostatic cortical actin array of living Arabidopsis (Arabidopsis thaliana) epidermal cells with genetic and/or small molecule inhibitor approaches to stably or acutely disrupt nucleator activity. We found that Arp2/3 mutants or acute CK-666 treatment markedly reduced the frequency of side-branched nucleation events as well as overall actin filament abundance. We also confirmed that plant formins contribute to side-branched filament nucleation in vivo. Surprisingly, simultaneous inhibition of both classes of nucleator increased overall actin filament abundance and enhanced the frequency of de novo nucleation events by an unknown mechanism. Collectively, our findings suggest that multiple actin nucleation mechanisms cooperate to generate and maintain the homeostatic cortical array of plant epidermal cells.
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Actinas , Arabidopsis , Actinas/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Forminas/metabolismo , Complexo 2-3 de Proteínas Relacionadas à Actina/genética , Complexo 2-3 de Proteínas Relacionadas à Actina/metabolismo , Citoesqueleto de Actina/metabolismo , Células Epidérmicas/metabolismoRESUMO
Anthracycline chemotherapy is associated with the left ventricular (LV) dysfunction, but the conventional echocardiographic parameter is insensitive in detecting subclinical cardiac dysfunction, and the role of echocardiography in children cancer survivors (CCSs) has not been well established. Here, the myocardial work (MW) was employed to evaluate the early effect of the anthracyclines on LV function in children lymphoma survivors, as well as to explore the clinical application value of this modality. 51 children lymphoma survivors treated with anthracyclines were included. During the treatments, the echocardiography was performed at baseline (T0 phase), the 3rd (T1 phase) and 6th (T2 phase) chemotherapeutic cycle, respectively. After that, the conventional echocardiographic parameters, LV global longitudinal strain (GLS), and global myocardial work (GMW) parameters were obtained. Finally, these echocardiographic parameters were compared to distinguish the differences among three groups, and correlation analysis was used to identify relationship between GMW parameters and LV GLS. Compared with the baseline, we found that there are no significant differences for LVEF and other conventional echocardiographic parameters after chemotherapy, but the value of LV lateral E/E' increased at T1 and T2 group. The GLS, global work index, global constructed work, and global work efficiency were decreased, while the global wasted work was increased after chemotherapy (all P < 0.05). The correlation analysis showed that the GLS has significant correlation with GMW parameters (all P < 0.001). The MW, as a new noninvasive echocardiography modality, could be used to quantitatively evaluate the LV MW in children lymphoma survivors treated with anthracyclines, which providing a sensitive method to early detect the children's LV dysfunction after the chemotherapy.
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AIMS: The increasing prevalence of inflammatory bowel disease is emerging as a significant global healthcare concern due to its recurrent episodes of intestinal inflammation. This study aims to explore the relationship between fear of progression and health-related quality of life in inflammatory bowel disease patients, investigating the sequential mediating roles of health literacy and self-care. DESIGN: A cross-sectional study. METHODS: Eligible participants diagnosed with inflammatory bowel disease were recruited through convenience sampling method at a tertiary hospital in Shenyang, China, between May 2022 and May 2023. A total of 241 participants completed the questionnaires regarding fear of progression, health literacy, self-care and quality of life. Data analysis was conducted using SPSS 25.0 and PROCESS plug-ins. RESULTS: (1) Fear of progression was found to be negatively associated with quality of life and had a directly predictive effect on quality of life. (2) Health literacy and self-care could independently mediate the relationship between fear of progression and quality of life. (3) There was a significant chain mediating effect of health literacy and self-care in the relationship between fear of progression and quality of life. CONCLUSION: Fear of progression could not only directly predict the quality of life in inflammatory bowel disease patients but also indirectly affect their quality of life through the chain mediation of health literacy and self-care. IMPACT: This study highlights the importance of nursing staff focusing on the interplay between fear of progression, health literacy, self-care and quality of life in caring for inflammatory bowel disease patients. Understanding the potential correlation mechanism underlying quality of life may help develop targeted care interventions to synergistically enhance health literacy and self-care in these patients. REPORTING METHOD: STROBE guidelines. PATIENT OR PUBLIC CONTRIBUTION: No public or patient contribution.
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Nonspecific amplification is a serious issue in DNA detection as it can lead to false-positive results and reduce specificity. It is very important to well understand its mechanism through sequencing nonspecific products. Here, an approach is developed using a nanopore sequencing technique after acquiring the long repetitive sequence of DNA products from nonspecific amplification. Based on the sequencing results, a new mechanism of nonspecific amplification designated as dynamic mismatched primer binding (DMPB) with the background DNA (bgDNA) is proposed. Unexpectedly, our findings show that the primers (â¼20 nt) can bind to bgDNA for primer extension when only 6-11 fully matched (9-14 mismatched) base pairs are formed. After the single-stranded DNAs (ssDNAs) attached to the first primer are produced, more interestingly, with the aid of DNA polymerase, the other primer can bind to these ssDNAs in the case that the fully matched base pairs formed between them are even shorter than 6 bp. As a result, perfect "seeds" for polymerase chain reaction with information on both primers are produced so that exponential nonspecific amplification can occur. The DMPB mechanism can explain nonspecific amplification in other approaches as well. Finally, a mini-hairpin DNA is used to effectively inhibit nonspecific amplification by preventing the formation of an unexpected primer-bgDNA complex.
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DNA Polimerase Dirigida por DNA , DNA , DNA/genética , Reação em Cadeia da Polimerase/métodos , Primers do DNA , Sequências Repetitivas de Ácido Nucleico , DNA de Cadeia Simples , Técnicas de Amplificação de Ácido Nucleico/métodosRESUMO
One of the strategies that plants adopt to cope with an unfavorable environment is to sacrifice their growth for tolerance. Although moderate salt stress can induce root growth inhibition, the molecular mechanisms regulating this process have yet to be elucidated. Here, we found that overexpression of a zinc finger-homeodomain family transcription factor, HOMEOBOX PROTEIN 24 (HB24), led to longer primary roots than in the wild-type in the presence of 125 mM NaCl, whereas this phenotype was reversed for the hb24 loss-of-function mutant, indicating a negative impact of HB24 on salt-induced root growth inhibition. We then found that salt stress triggered the degradation of HB24 via the ubiquitin-proteasome pathway, as mediated by a plant U-box type E3 ubiquitin ligase 30 (PUB30) that directly targets HB24. We verified that HB24 is able to directly bind to the promoters of Sugars Will Eventually be Exported Transporter 11/12 (SWEET11/12) to regulate their expression in roots. Through genetic and biochemical assays, we further demonstrated that the HB24-SWEET11 module plays a negative role in salt-induced root growth inhibition. Therefore, we propose that under salt stress, PUB30 mediates HB24's degradation, thereby downregulating the expression of SWEET11, resulting in reduced sucrose supply and root growth inhibition.
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Proteínas de Arabidopsis , Arabidopsis , Raízes de Plantas , Estresse Salino , Sacarose , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulação para Baixo/genética , Regulação para Baixo/fisiologia , Regulação da Expressão Gênica de Plantas , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Estresse Salino/genética , Estresse Salino/fisiologia , Estresse Fisiológico/genética , Sacarose/metabolismo , Ubiquitina-Proteína Ligases/metabolismoRESUMO
Abernethy malformation, also known as congenital extrahepatic shunt, is a rare anomaly, which is characterized by partial or complete diversion of the portal blood into the systemic venous circulation. The clinical manifestations of Abernethy malformation during childhood include neonatal cholestasis, failure to thrive, mental retardation, and other congenital defects. We report a case of Abernethy malformation Type II in a 9-year-old boy, whose left ventricle was slightly enlarged because of several major aortopulmonary collateral arteries (MAPCAs) but laboratory examinations were normal 5 years earlier. The characteristics of congenital heart disease in patients with Abernethy malformation are discussed. We propose that physicians should be aware of the possibility of Abernethy malformation in children with enlargement of the left ventricular due to systemic-pulmonary collateral circulation.
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Cardiopatias Congênitas , Malformações Vasculares , Masculino , Criança , Humanos , Recém-Nascido , Veia Porta/anormalidades , Malformações Vasculares/diagnóstico , Malformações Vasculares/diagnóstico por imagem , Cardiopatias Congênitas/complicações , Cardiopatias Congênitas/diagnóstico por imagemRESUMO
The rotational Doppler effect (RDE) provides an efficient way to measure rotational frequency using an optical vortex beam. Crucially, most research based on the RDE just involves a spinning object or a spinning object coupled with a longitudinal velocity along the beam propagation. We analyze the interaction mechanism between optical orbital angular momentum and a spinning object with circular procession and experimentally demonstrate simultaneous measurements of two rotational frequencies. This technique broadens application of the RDE in optical metrology and remote detection of targets with micro-motions.
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BACKGROUND: Chronic pain is a common disease; about 20% of people worldwide suffer from it. While compared with the research on the prevalence and management of chronic pain in developed countries, there is a relative lack of research in this field in China. This research aims to construct the China Pain Health Index (CPHI) to evaluate the current status of the prevalence and management of chronic pain in the Chinese population. METHODS: The dimensions and indicators of CPHI were determined through literature review, Delphi method, and analytical hierarchy process model, and the original values ââof relevant indicators were obtained by collecting multi-source data. National and sub-provincial scores of CPHI (2020) were calculated by co-directional transformation, standardization, percentage transformation of the aggregate, and weighted summation. RESULTS: The highest CPHI score in 2020 is Beijing, and the lowest is Tibet. The top five provinces are Beijing (67.64 points), Shanghai (67.04 points), Zhejiang (65.74 points), Shandong (61.16 points), and Tianjin (59.99 points). The last five provinces are Tibet (33.10 points), Ningxia (37.24 points), Guizhou (39.85 points), Xinjiang (39.92 points), and Hainan (40.38 points). The prevalence of chronic pain is severe in Heilongjiang, Chongqing, Guizhou, Sichuan, and Fujian. Guizhou, Hainan, Xinjiang, Beijing, and Guangdong display a high burden of chronic pain. The five provinces of Guangdong, Shanghai, Beijing, Jiangsu, and Zhejiang have better treatment for chronic pain, while Tibet, Qinghai, Jilin, Ningxia, and Xinjiang have a lower quality of treatment. Beijing, Shanghai, Qinghai, Guangxi, and Hunan have relatively good development of chronic pain disciplines, while Tibet, Sichuan, Inner Mongolia, Hebei, and Guizhou are relatively poor. CONCLUSION: The economically developed provinces in China have higher CPHI scores, while economically underdeveloped areas have lower scores. The current pain diagnosis and treatment situation in economically developed regions is relatively good, while that in financially underdeveloped areas is rather poor. According to the variations in the prevalence and management of chronic pain among populations in different provinces in China, it is necessary to implement chronic pain intervention measures adapted to local conditions.
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Dor Crônica , Humanos , China/epidemiologia , Prevalência , Dor Crônica/epidemiologia , Dor Crônica/terapiaRESUMO
Homozygous familial hypercholesterolemia (HoFH) is a rare, life-threatening genetic disorder characterized by an extremely elevated serum level of low-density lipoprotein cholesterol (LDL-C) and accelerated premature atherosclerotic cardiovascular diseases (ASCVD). However, the detailed mechanism of how the pathogenic mutations of HoFH trigger the acceleration of ASCVD is not well understood. Therefore, we performed high-throughput RNA and small RNA sequencing on the peripheral blood RNA samples of six HoFH patients and three healthy controls. The gene and miRNA expression differences were analyzed, and seven miRNAs and six corresponding genes were screened out through regulatory network analysis. Validation through quantitative PCR of genes and miRNAs from 52 HoFH patients and 20 healthy controls revealed that the expression levels of hsa-miR-486-3p, hsa-miR-941, and BIRC5 were significantly upregulated in HoFH, while ID1, PLA2G4C, and CACNA2D2 were downregulated. Spearman correlation analysis found that the levels of ID1, hsa-miR-941, and hsa-miR-486-3p were significantly correlated with additional ASCVD risk factors in HoFH patients. This study represents the first integrated analysis of transcriptome and miRNA expression profiles in patients with HoFH, a rare disease, and as a result, six differentially expressed miRNAs/genes that may be related to atherosclerosis in HoFH are reported. The miRNA-mRNA regulatory network may be the critical regulation mechanism by which ASCVD is accelerated in HoFH.
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Aterosclerose , Hipercolesterolemia Familiar Homozigota , MicroRNAs , Aterosclerose/complicações , Aterosclerose/genética , Hipercolesterolemia Familiar Homozigota/complicações , Hipercolesterolemia Familiar Homozigota/genética , Humanos , MicroRNAs/genética , RNA Mensageiro/genéticaRESUMO
Attention deficits (AD) and disruptive behavior (DB) are highly comorbid youth externalizing behaviors. This study aimed to study reliable functional brain networks shared by AD and DB in youth aged from 8 to 21 years from the Philadelphia Neurodevelopmental Cohort (PNC). The PNC study assessed AD and DB behaviors via Kiddie-Schedule for Affective Disorders and Schizophrenia (K-SADS). This study employed sparse canonical correlation analysis (SCCA) to examine the correlation of AD and DB behaviors with resting-state functional connectivity maps of the brain regions identified via activation likelihood estimation (ALE) meta-analyses on attention deficit/hyperactivity disorder (ADHD) and DB disorder (DBD). Our meta-analyses identified that the middle cingulate cortex, pre-supplementary motor area (pre-SMA), and striatum had a great consensus in existing ADHD studies and the amygdala and inferior parietal lobule were consistently found in existing DBD studies. Our SCCA analysis revealed that the AD and DB behavioral items relevant to inattention and delinquency were correlated with the functional connectivity of the pre-SMA with the ventral attentional and frontoparietal networks (FPN), and the striatum with the default mode (DMN) and dorsal attentional networks. The AD and DB behavioral items relevant to inattention and irritability were associated with the functional connectivity between the amygdala and the DMN and FPN. Our findings suggest that the functional organization of the ADHD- and DBD-related brain regions provides insights on the shared neural basis in AD and DB.
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Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico por imagem , Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Mapeamento Encefálico/métodos , Encéfalo/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Vias Neurais/fisiopatologia , Comportamento Problema , Adolescente , Criança , Feminino , Humanos , Masculino , Adulto JovemRESUMO
The role of lipocalin 2 (LCN2) in pulmonary hypertension (PH) in pediatric patients with congenital heart disease (CHD) remains unclear. We sought to investigate whether LCN2 could be a potential biomarker for PH in pediatric patients who underwent surgery for CHD. From December 2018 to February 2020, patients undergoing surgical repair for congenital defects with and without PH were identified. Healthy children without CHD and PH served as controls. A mean pulmonary artery pressure (mPAP) >20 mmHg was used as the definition of PH. Blood samples and echocardiograms were obtained in all patients and right heart catheterization was performed in 79 patients. Multivariable logistic regression analysis was used to determine potential predictors for PH. Among 102 patients, the median age was 10 [Interquartile range (IQR) 7.0-13] months, and 37.5% were female. Compared to non-PH patients and controls, PH patients showed elevated levels of LCN2 (P < 0.001). In addition, LCN2 levels positively correlated with the invasive haemodynamic indices of PH. In univariate regression, LCN2 (odds ratio = 2.69 [1.06-5.31], P < 0.001), N-Terminal pro Brain Natriuretic Peptide (NT-proBNP) (OR = 1.91 [1.21-7.56], P = 0.03) and high-sensitive troponin T (hsTnT) (OR = 1.36 [1.01-3.57], P = 0.01) were associated with PH; however, only LCN2 (OR = 1.68 [1.04-4.52], P = 0.03) was significantly associated with PH on multivariate analysis. In conclusion, children with PH had increased LCN2 expression. LCN2 levels positively correlated with invasive indices of PH. These results indicate LCN2 could be a useful biomarker for prediction of PH in pediatric CHD cases.
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Cardiopatias Congênitas , Hipertensão Pulmonar , Adolescente , Biomarcadores , Criança , Ecocardiografia , Feminino , Cardiopatias Congênitas/complicações , Cardiopatias Congênitas/diagnóstico , Cardiopatias Congênitas/cirurgia , Humanos , Hipertensão Pulmonar/diagnóstico , Hipertensão Pulmonar/etiologia , Lipocalina-2 , Masculino , Peptídeo Natriurético Encefálico , Fragmentos de PeptídeosRESUMO
We study the problem of stochastic multiple-arm identification, where an agent sequentially explores a size-k subset of arms (also known as a super arm) from given n arms and tries to identify the best super arm. Most work so far has considered the semi-bandit setting, where the agent can observe the reward of each pulled arm or assumed each arm can be queried at each round. However, in real-world applications, it is costly or sometimes impossible to observe a reward of individual arms. In this study, we tackle the full-bandit setting, where only a noisy observation of the total sum of a super arm is given at each pull. Although our problem can be regarded as an instance of the best arm identification in linear bandits, a naive approach based on linear bandits is computationally infeasible since the number of super arms K is exponential. To cope with this problem, we first design a polynomial-time approximation algorithm for a 0-1 quadratic programming problem arising in confidence ellipsoid maximization. Based on our approximation algorithm, we propose a bandit algorithm whose computation time is O(log K), thereby achieving an exponential speedup over linear bandit algorithms. We provide a sample complexity upper bound that is still worst-case optimal. Finally, we conduct experiments on large-scale data sets with more than 1010 super arms, demonstrating the superiority of our algorithms in terms of both the computation time and the sample complexity.
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We evaluated 26 microemulsion liquid chromatography (MELC) systems for their potential as high-throughput screening platforms capable of modeling the partitioning behaviors of drug compounds in an n-octanol-water system, and for predicting the lipophilicity of those compounds (i.e. logP values). The MELC systems were compared by cluster analysis and a linear solvation energy relationship (LSER)-based method, and the optimal system was identified by comparing their Euclidean distances with the LSER coefficients. The most effective MELC system had a mobile phase consisting of 6.0% (w/w) Brij35 (a detergent), 6.6% (w/w) butanol, 0.8% (w/w) cyclohexane, 86.6% (w/w) buffer solution and 8 mm cetyltrimethyl ammonium bromide. The reliability of the established platform was confirmed by the agreement between the experimental data and the predicted values. The logP values of the ingredients of danshen root (Salvia miltiorrhiza Radix et Rhizoma) were then predicted. Copyright © 2015 John Wiley & Sons, Ltd.
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Lipídeos/química , Raízes de Plantas/química , Salvia miltiorrhiza/química , Cromatografia Líquida , Análise por Conglomerados , Emulsões , Reprodutibilidade dos Testes , SolubilidadeRESUMO
The association between polymorphisms of the human ATP binding cassette subfamily B member 1 (ABCB1) gene and opioid response has attracted intense attention recently. As the ABCB1 gene encodes for the transporter P-glycoprotein in the brain and intestine involved in the pharmacokinetics of opioids, we investigated the effects of ABCB1 genetic polymorphisms on doses of opioids for pain relief and determined which pharmacokinetic process was affected in cancer pain patients. Sixty-eight cancer pain patients admitted for intrathecal therapy (ITT) were included. The association between ABCB1 genetic polymorphisms (C3435T, C1236T, G2677T/A and A61G) and systemic doses of opioids before ITT were investigated. Concentrations of oxycodone in plasma and cerebrospinal fluid (CSF) were determined by HPLC-MS/MS in 17 patients treated with oral oxycodone before ITT, and the influences of ABCB1 genetic polymorphisms on plasma-concentration to oral-dose ratios and CSF-concentration to plasma-concentration ratios of oral oxycodone were further analyzed. ABCB1 C3435T and G2677T/A polymorphisms were significantly associated with systemic doses of opioids before ITT, which coincided with the influences of ABCB1 C3435T and G2677T/A polymorphisms on the ratios of plasma-concentration to oral-dose. However, no significant difference was found in ratios of CSF-concentration to plasma-concentration among ABCB1 SNP genotypes. The present study provided the first evidence that ABCB1 C3435T and G2677T/A polymorphisms affect opioid requirement in cancer pain patients via altering transportation function of P-glycoprotein in the intestine, which will further expand our knowledge about pharmacokinetics of opioids and could contribute to the individualization of opioids use.
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Subfamília B de Transportador de Cassetes de Ligação de ATP , Analgésicos Opioides , Oxicodona , Polimorfismo de Nucleotídeo Único , Humanos , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Masculino , Feminino , Analgésicos Opioides/farmacocinética , Analgésicos Opioides/administração & dosagem , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Idoso , Oxicodona/farmacocinética , Oxicodona/administração & dosagem , Dor do Câncer/tratamento farmacológico , Dor do Câncer/genética , Adulto , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Mucosa Intestinal/metabolismo , GenótipoRESUMO
BACKGROUND: Polylactic acid (PLA), a biodegradable polymer, has the potential to replace (at least partially) traditional petroleum-based plastics, minimizing "white pollution". However, cost-effective production of optically pure L-lactic acid is needed to achieve the full potential of PLA. Currently, starch-based glucose is used for L-lactic acid fermentation by lactic acid bacteria. Due to its competition with food resources, an alternative non-food substrate such as cellulosic biomass is needed for L-lactic acid fermentation. Nevertheless, the substrate (sugar stream) derived from cellulosic biomass contains significant amounts of xylose, which is unfermentable by most lactic acid bacteria. However, the microorganisms that do ferment xylose usually carry out heterolactic acid fermentation. As a result, an alternative strain should be developed for homofermentative production of optically pure L-lactic acid using cellulosic biomass. RESULTS: In this study, an ethanologenic Escherichia coli strain, SZ470 (ΔfrdBC ΔldhA ΔackA ΔpflB ΔpdhR ::pflBp6-acEF-lpd ΔmgsA), was reengineered for homofermentative production of L-lactic acid from xylose (1.2 mole xylose = > 2 mole L-lactic acid), by deleting the alcohol dehydrogenase gene (adhE) and integrating the L-lactate dehydrogenase gene (ldhL) of Pediococcus acidilactici. The resulting strain, WL203, was metabolically evolved further through serial transfers in screw-cap tubes containing xylose, resulting in the strain WL204 with improved anaerobic cell growth. When tested in 70 g L-1 xylose fermentation (complex medium), WL204 produced 62 g L-1 L-lactic acid, with a maximum production rate of 1.631 g L-1 h-1 and a yield of 97% based on xylose metabolized. HPLC analysis using a chiral column showed that an L-lactic acid optical purity of 99.5% was achieved by WL204. CONCLUSIONS: These results demonstrated that WL204 has the potential for homofermentative production of L-lactic acid using cellulosic biomass derived substrates, which contain a significant amount of xylose.
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Escherichia coli/metabolismo , Ácido Láctico/biossíntese , Xilose/metabolismo , Álcool Desidrogenase/deficiência , Álcool Desidrogenase/genética , Proteínas de Bactérias/genética , Biomassa , Fermentação , Engenharia Genética , L-Lactato Desidrogenase/genética , Ácido Láctico/síntese química , Pediococcus/enzimologia , Pediococcus/genética , Plasmídeos/genética , Plasmídeos/metabolismo , Poliésteres , Polímeros/síntese química , EstereoisomerismoRESUMO
OBJECTIVE: In this study, we constructed a recombinant Escherichia coli strain for the production of high-purity L-lactic acid, using a homoethanol fermenting mutant E. coli SZ470 (deltafrdBC deltaldhA deltaackA deltafocA-pflB deltapdhR: :pflBp6-pflBrbs-aceEF-lpd) as the starting strain. METHODS: By using homologous recombination, we deleted the adhE gene from SZ470 to obtain a mutant Escherichia coli JH01, which could not grow under anaerobic conditions. Then we cloned the L-lactate dehydrogenase gene (ldhL) of Pediococcus acidilactici and inserted it into the chromosome of JH01 via electroporation to obtain a recombinant strain Escherichia coli JH12. We evaluated the L-lactic acid production of the recombinant strain in a 15 L fermenter. RESULTS: In 10 L LB medium supplemented with 6% glucose, JH12 maintained maximal cell growth and an efficient L-lactic acid production rate for 36 h. Glucose consumption rate achieved was 1.46 g/(L x h) and L-lactic acid production rate was 1.14 g/(L x h). The results also show that 41.13 g/L lactic acid was produced, achieving a purity of 95.69% (based on total fermentation products). Xylose consumption rate was 0.88 g/(L x h) and L-lactic acid production rate was 0.60 g/(L x h). The production of lactic acid was 34.73 g/L, achieving a purity of 98%. There were no succinic acid and formic acid detected and only little amount of acetic acid generated during the fermentation. CONCLUSION: We constructed a homolactic acid fermentation strain E. coli JH12, which could efficiently convert glucose and xylose into high-purity L-lactic acid. JH12 could have great potential in industrial fermentation for L-lactic acid production.
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Escherichia coli/genética , Escherichia coli/metabolismo , Ácido Láctico/biossíntese , Pentoses/metabolismo , Álcool Desidrogenase/genética , Álcool Desidrogenase/metabolismo , Aldeído Oxirredutases/genética , Aldeído Oxirredutases/metabolismo , Escherichia coli/crescimento & desenvolvimento , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Fermentação/genética , Fermentação/fisiologia , Engenharia Genética/métodos , Glucose/metabolismo , L-Lactato Desidrogenase/genética , L-Lactato Desidrogenase/metabolismo , Ácido Láctico/metabolismo , Pediococcus/genética , Pediococcus/metabolismo , Xilose/metabolismoRESUMO
Purpose: Few studies have explored factors that may account for potential mechanisms between perceived coronavirus disease 2019 (COVID-19) stress and online aggression. The current study examined a moderated mediation model with anxiety as a mediator and perceived anonymity as a moderator. Methods: A cross-sectional study was conducted. 3,069 participants across China completed scales assessing perceived COVID-19 stress, anxiety, online aggression, and perceived anonymity. Results: Perceived COVID-19 stress was positively related to online aggression. The association between perceived COVID-19 stress and online aggression was mediated by anxiety. Besides, the relationship between perceived COVID-19 stress and online aggression, as well as the relationship between anxiety and online aggression were moderated by perceived anonymity. Conclusion: This study explains the possible potential mechanisms for reducing online aggression in the context of COVID-19. In order to intervene in online aggression, psychological strategies are supposed to be drawn to reduce anxiety and perceived anonymity.
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The microtubule (MT) network is a highly dynamic subcellular structure playing an important role in the growth and development of plants, and it is able to respond to biotic and abiotic environmental signals. Recent literature shows that microtubules play a key role in the tolerance of plants to salt stress. For example, salt stress induces microtubules to undergo a process of depolymerization-repolymerization, which is necessary for Arabidopsis seedlings to survive under these conditions. However, the potential cellular and molecular mechanisms still need to be further studied. Here, we describe the protocol for salt treatment of Arabidopsis seedlings and imaging the MT array by confocal laser scanning microscopy. We also introduce the AnalyzeSkeleton (2D/3D) plugin for quantitative analysis of the microtubule array after salt stress. The application of such an image processing method can rapidly develop an appreciation of the role of microtubules in the salt stress response of plants.
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Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Microtúbulos/metabolismo , Estresse Salino , Plântula/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Regulação da Expressão Gênica de PlantasRESUMO
Purpose: Pharmacists are key members of the pain management interdisciplinary team in many developed countries. However, the implementation of clinical pharmacy services in pain management is impeded by the imbalance between the pain physicians and clinical pharmacists specializing in pain management in China. The purpose of this study was to elucidate the perceptions, expectations and current experience of Chinese pain physicians regarding clinical pharmacy services. Patients and Methods: An anonymous, self-administered questionnaire was designed according to previously published studies with minor modifications and distributed online to 1100 pain physicians selected randomly in hospitals across all 31 provinces of mainland China in 2021. Data were analyzed using descriptive and inferential statistics. Results: A total of 1071 valid questionnaires were included for analysis. The pain physicians were from all 31 provinces of mainland China and most of them were from tertiary hospitals holding an undergraduate degree. Among listed kinds of clinical pharmacy services, pain physicians were less comfortable with pharmacists treating minor illnesses (p < 0.001). Pain physicians' experiences with clinical pharmacy services were far less than their expectations (p < 0.001), which is in line with the results that most of pain physicians (65.9%) interacted with pharmacists at a frequency of less than once a week. Significant differences in the experiences were found among ages (p < 0.01) and among years of work experience (p < 0.05) of pain physicians. Pain physicians' expectations of pharmacists were positively correlated with their experiences with clinical pharmacy services (p < 0.001). Conclusion: Pain physicians in China had positive perceptions and high expectations, but relatively low experiences regarding clinical pharmacy services. Expanding clinical pharmacist pain management credentialing and increasing pain physicians' exposure to clinical pharmacy services are favourable to support the interdisciplinary collaboration in pain management in China.
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INTRODUCTION: Intrathecal therapy (ITT) via an implanted system was demonstrated for the treatment of refractory cancer pain for decades. Recently, the dissemination of ITT is enhanced in an external system way in Asia for a lower implantation cost. This study compares the efficacy, safety, and cost of the two ITT systems in refractory cancer pain patients in China. METHODS: One hundred and thirty-nine cancer pain patients who underwent implantation of the ITT system were included. One hundred and three patients received ITT via the external system (external group), while 36 patients received ITT via the implanted system (implanted group). A 1:2 propensity score matching procedure was used to yield a total of 89 patients for the final analysis. Medical records of included patients were retrospectively reviewed and pain scores, incidences of complications, and costs were compared. RESULTS: ITT via the external system provided pain relief as potent as ITT via the implanted system but was less time-consuming in the implantation phase (13 vs. 19 days, p < .01). Nausea/vomiting and urinary retention were the most frequent adverse events in both external and implanted groups (32.14%, 16.07% vs. 36.36%, 21.21%). No significant difference was found in the incidences of all kinds of complications. Compared to the implanted group, the external group cost less for the initial implantation (7268 vs. 26,275 US dollar [USD], p < .001) but had a significant higher maintenance cost (606.62 vs. 20.23 USD calculated monthly, p < .001). CONCLUSIONS: ITT via the external system is as effective and safe as that via the implanted system and has the advantage of being cheap in the upfront implantation but costs more during the maintenance process in China.