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1.
Plant Cell ; 36(6): 2310-2327, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38442314

RESUMO

The dynamic changes in membrane phospholipids affect membrane biophysical properties and cell signaling, thereby influencing numerous biological processes. Nonspecific phospholipase C (NPC) enzymes hydrolyze common phospholipids to release diacylglycerol (DAG), which is converted to phosphatidic acid (PA) and other lipids. In this study, 2 Arabidopsis (Arabidopsis thaliana) tandemly arrayed genes, NPC3 and NPC4, were identified as critical factors modulating auxin-controlled plant growth and tropic responses. Moreover, NPC3 and NPC4 were shown to interact with the auxin efflux transporter PIN-FORMED2 (PIN2). The loss of NPC3 and NPC4 enhanced the endocytosis and vacuolar degradation of PIN2, which disrupted auxin gradients and slowed gravitropic and halotropic responses. Furthermore, auxin-triggered activation of NPC3 and NPC4 is required for the asymmetric PA distribution that controls PIN2 trafficking dynamics and auxin-dependent tropic responses. Collectively, our study reveals an NPC-derived PA signaling pathway in Arabidopsis auxin fluxes that is essential for fine-tuning the balance between root growth and environmental responses.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos , Fosfolipases Tipo C , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Endocitose , Gravitropismo , Ácidos Indolacéticos/metabolismo , Ácidos Fosfatídicos/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Raízes de Plantas/genética , Plantas Geneticamente Modificadas , Transdução de Sinais , Fosfolipases Tipo C/metabolismo , Fosfolipases Tipo C/genética
2.
J Virol ; 98(1): e0162523, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38084960

RESUMO

Porcine epidemic diarrhea virus (PEDV) is an enteric coronavirus that causes high mortality in piglets, thus posing a serious threat to the world pig industry. Porcine epidemic diarrhea (PED) is related to the imbalance of sodium absorption by small intestinal epithelial cells; however, the etiology of sodium imbalanced diarrhea caused by PEDV remains unclear. Herein, we first proved that PEDV can cause a significant decrease in Na+/H+ exchanger 3 (NHE3) expression on the cell membrane, in a viral dose-dependent manner. Further study showed that the PEDV nucleocapsid (N) protein participates in the regulation of NHE3 activity through interacting with Ezrin. Flame atomic absorption spectroscopy results indicated a serious imbalance in Na+ concentration inside and outside cells following overexpression of PEDV N. Meanwhile, molecular docking technology identified that the small molecule drug Pemetrexed acts on the PEDV N-Ezrin interaction region. It was confirmed that Pemetrexed can alleviate the imbalanced Na+ concentration in IPEC-J2 cells and the diarrhea symptoms of Rongchang pigs caused by PEDV infection. Overall, our data suggest that the interaction between PEDV N and Ezrin reduces the level of phosphorylated Ezrin, resulting in a decrease in the amount of NHE3 protein on the cell membrane. This leads to an imbalance of intracellular and extracellular Na+, which causes diarrhea symptoms in piglets. Pemetrexed is effective in relieving diarrhea caused by PEDV. Our results provide a reference to screen for anti-PEDV targets and to develop drugs to prevent PED.IMPORTANCEPorcine epidemic diarrhea (PED) has caused significant economic losses to the pig industry since its initial outbreak, and the pathogenic mechanism of porcine epidemic diarrhea virus (PEDV) is still under investigation. Herein, we found that the PEDV nucleocapsid protein interacts with Ezrin to regulate Na+/H+ exchanger 3 activity. In addition, we screened out Pemetrexed, a small molecule drug, which can effectively alleviate pig diarrhea caused by PEDV. These results provide support for further exploration of the pathogenesis of PEDV and the development of drugs to prevent PED.


Assuntos
Infecções por Coronavirus , Vírus da Diarreia Epidêmica Suína , Doenças dos Suínos , Animais , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/veterinária , Diarreia/tratamento farmacológico , Diarreia/veterinária , Simulação de Acoplamento Molecular , Proteínas do Nucleocapsídeo/metabolismo , Pemetrexede/metabolismo , Vírus da Diarreia Epidêmica Suína/fisiologia , Sódio/metabolismo , Trocador 3 de Sódio-Hidrogênio/metabolismo , Suínos , Doenças dos Suínos/tratamento farmacológico
3.
New Phytol ; 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39044442

RESUMO

Plants delicately regulate endogenous auxin levels through the coordination of transport, biosynthesis, and inactivation, which is crucial for growth and development. While it is well-established that the actin cytoskeleton can regulate auxin levels by affecting polar transport, its potential role in auxin biosynthesis has remained largely unexplored. Using LC-MS/MS-based methods combined with fluorescent auxin marker detection, we observed a significant increase in root auxin levels upon deletion of the actin bundling proteins AtFIM4 and AtFIM5. Fluorescent observation, immunoblotting analysis, and biochemical approaches revealed that AtFIM4 and AtFIM5 affect the protein abundance of the key auxin synthesis enzyme YUC8 in roots. AtFIM4 and AtFIM5 regulate the auxin synthesis enzyme YUC8 at the protein level, with its degradation mediated by the 26S proteasome. This regulation modulates auxin synthesis and endogenous auxin levels in roots, consequently impacting root development. Based on these findings, we propose a molecular pathway centered on the 'actin cytoskeleton-26S proteasome-YUC8-auxin' axis that controls auxin levels. Our findings shed light on a new pathway through which plants regulate auxin synthesis. Moreover, this study illuminates a newfound role of the actin cytoskeleton in regulating plant growth and development, particularly through its involvement in maintaining protein homeostasis via the 26S proteasome.

4.
Plant Cell ; 33(9): 3004-3021, 2021 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-34129038

RESUMO

Nitrate is both an important nutrient and a critical signaling molecule that regulates plant metabolism, growth, and development. Although several components of the nitrate signaling pathway have been identified, the molecular mechanism of nitrate signaling remains unclear. Here, we showed that the growth-related transcription factors HOMOLOG OF BRASSINOSTEROID ENHANCED EXPRESSION2 INTERACTING WITH IBH1 (HBI1) and its three closest homologs (HBIs) positively regulate nitrate signaling in Arabidopsis thaliana. HBI1 is rapidly induced by nitrate through NLP6 and NLP7, which are master regulators of nitrate signaling. Mutations in HBIs result in the reduced effects of nitrate on plant growth and ∼22% nitrate-responsive genes no longer to be regulated by nitrate. HBIs increase the expression levels of a set of antioxidant genes to reduce the accumulation of reactive oxygen species (ROS) in plants. Nitrate treatment induces the nuclear localization of NLP7, whereas such promoting effects of nitrate are significantly impaired in the hbi-q and cat2 cat3 mutants, which accumulate high levels of H2O2. These results demonstrate that HBI-mediated ROS homeostasis regulates nitrate signal transduction through modulating the nucleocytoplasmic shuttling of NLP7. Overall, our findings reveal that nitrate treatment reduces the accumulation of H2O2, and H2O2 inhibits nitrate signaling, thereby forming a feedback regulatory loop to regulate plant growth and development.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/fisiologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Homeostase , Nitratos/metabolismo , Espécies Reativas de Oxigênio , Transdução de Sinais , Proteínas de Arabidopsis/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo
5.
Org Biomol Chem ; 22(32): 6443-6484, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39041389

RESUMO

Alkynes are important in organic synthesis. This review mainly focuses on recent advances (2013-2023) on alkynes with C-S bond formation, based on more than 30 types of sulfur reagents. The reactions of alkynes with various sulfur-containing compounds including RSSR (disulfides), RSH (thiols), S8 (elemental sulphur), alkynyl thioethers, RSCN, AgSCF3, K2S, Na2S, dithiane, RSCl, NFSI, RNCS, EtOCS2K, thiocarbamate, RSONH2, thiourea, sulfoxide, RSO2N3, CS2, RSO2NH2, RSO2NHNH2, RSO2Cl, RSO2Oar, RSO2SR', DABCO·(SO2)2, Na2S2O5, K2S2O5, RSO2H, RSO2Na and related compounds are discussed. Diverse mechanisms such as radical, electrophilic/nucleophilic addition, rearrangement, C-C bond cleavage, and CuAAC are discussed. The content is organized by substrates and reactivity patterns. We hope it will help in future research in this area.

6.
BMC Public Health ; 24(1): 322, 2024 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-38287333

RESUMO

BACKGROUND: Self-monitoring is crucial for behavioral weight loss. However, few studies have examined the role of self-monitoring using mixed methods, which may hinder our understanding of its impact. METHODS: This study examined self-monitoring data from 61 Chinese adults who participated in a 5-week online group intervention for weight loss. Participants reported their baseline Body Mass Index (BMI), weight loss motivation, and engaged in both daily quantitative self-monitoring (e.g., caloric intake, mood, sedentary behavior, etc.) and qualitative self-monitoring (e.g., daily log that summarizes the progress of weight loss). The timeliness of participants' daily self-monitoring data filling was assessed using a scoring rule. One-way repeated measurement ANOVA was employed to analyze the dynamics of each self-monitoring indicator. Correlation and regression analyses were used to reveal the relationship between baseline data, self-monitoring indicators, and weight change. Content analysis was utilized to analyze participants' qualitative self-monitoring data. Participants were categorized into three groups based on their weight loss outcomes, and a chi-square test was used to compare the frequency distribution between these groups. RESULTS: After the intervention, participants achieved an average weight loss of 2.52 kg (SD = 1.36) and 3.99% (SD = 1.96%) of their initial weight. Daily caloric intake, weight loss satisfaction, frequency of daily log, and the speed of weight loss showed a downward trend, but daily sedentary time gradually increased. Moreover, regression analysis showed that baseline BMI, weight loss motivation, and timeliness of daily filling predicted final weight loss. Qualitative self-monitoring data analysis revealed four categories and nineteen subcategories. A significant difference in the frequency of qualitative data was observed, with the excellent group reporting a greater number of daily logs than expected in all categories and most subcategories, and the moderate and poor groups reporting less than expected in all categories and most subcategories. CONCLUSION: The self-monitoring data in short-term online group intervention exhibited fluctuations. Participants with higher baseline BMI, higher levels of weight loss motivation, and timely self-monitoring achieved more weight loss. Participants who achieved greater weight loss reported a higher quantity of qualitative self-monitoring data. Practitioners should focus on enhancing dieters' weight loss motivation and promote adherence to self-monitoring practices.


Assuntos
Comportamentos Relacionados com a Saúde , Redução de Peso , Adulto , Humanos , Índice de Massa Corporal , Terapia Comportamental/métodos , Ingestão de Energia
7.
Actas Esp Psiquiatr ; 52(5): 724-732, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39403912

RESUMO

BACKGROUND: Schisandra extract has therapeutic and preventive effects on Alzheimer's disease (AD). Therefore, this study evaluated the anti-AD potential of Schisandrin A (SCH A) using an in vitro cell model. METHODS: SH-SY5Y and SK-N-SH cells were treated with 20 µM amyloid ß-protein (Aß)25-35. The Aß25-35-induced cells were then exposed to different concentrations of SCH A (1, 5, 10, 15 µg/mL). Moreover, to further explore the role of the extracellular signal-regulated kinase (ERK)/mitogen-activated protein kinase (MAPK) pathway in the anti-AD effects of SHC A, SH-SY5Y cells were treated with SCH A following incubation with ERK activator LM22B-10. The impact of SCH A on cell viability and apoptosis was evaluated using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) and flow cytometry. Furthermore, the oxidative stress markers and inflammatory cytokine levels were also assessed. The reactive oxygen species (ROS) levels were examined using 2',7'-Dichlorodihydrofluorescein Diacetate (DCFH-DA) method. Finally, Western blot analysis was employed to evaluate the phospho-ERK1/2 (p-ERK1/2) and ERK1/2. RESULTS: We observed that SCH A treatment (5, 10, 15 µg/mL) substantially increased the cell viability (p < 0.05), and reduced the apoptosis rate (10 and 15 µg/mL) in SH-SY5Y and SK-N-SH cells (p < 0.05). SCH A significantly ameliorated oxidative stress and reduced inflammatory cytokine levels in Aß25-35-induced cells (p < 0.05). Furthermore, SCH A up-regulated the p-ERK1/2 to ERK1/2 ratio in Aß25-35-induced cells. However, LM22B-10 treatment was found to exacerbate this effect of SCH A (p < 0.05). CONCLUSION: SCH A reduces the Aß25-35-induced inflammatory response and oxidative stress in SH-SY5Y and SK-N-SH cells, and the activation of the ERK/MAPK signaling pathway was related to its potential mechanism.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Ciclo-Octanos , Inflamação , Lignanas , Estresse Oxidativo , Fragmentos de Peptídeos , Compostos Policíclicos , Estresse Oxidativo/efeitos dos fármacos , Lignanas/farmacologia , Humanos , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Fragmentos de Peptídeos/metabolismo , Compostos Policíclicos/farmacologia , Compostos Policíclicos/uso terapêutico , Ciclo-Octanos/farmacologia , Ciclo-Octanos/uso terapêutico , Inflamação/tratamento farmacológico , Inflamação/induzido quimicamente , Inflamação/metabolismo , Células Tumorais Cultivadas
8.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(4): 394-402, 2024 Apr 15.
Artigo em Zh | MEDLINE | ID: mdl-38660904

RESUMO

OBJECTIVES: To compare the repair effects of different doses of human umbilical cord mesenchymal stem cells (hUC-MSCs) on white matter injury (WMI) in neonatal rats. METHODS: Two-day-old Sprague-Dawley neonatal rats were randomly divided into five groups: sham operation group, WMI group, and hUC-MSCs groups (low dose, medium dose, and high dose), with 24 rats in each group. Twenty-four hours after successful establishment of the neonatal rat white matter injury model, the WMI group was injected with sterile PBS via the lateral ventricle, while the hUC-MSCs groups received injections of hUC-MSCs at different doses. At 14 and 21 days post-modeling, hematoxylin and eosin staining was used to observe pathological changes in the tissues around the lateral ventricles. Real-time quantitative polymerase chain reaction was used to detect the quantitative expression of myelin basic protein (MBP) and glial fibrillary acidic protein (GFAP) mRNA in the brain tissue. Immunohistochemistry was employed to observe the expression levels of GFAP and neuron-specific nuclear protein (NeuN) in the tissues around the lateral ventricles. TUNEL staining was used to observe cell apoptosis in the tissues around the lateral ventricles. At 21 days post-modeling, the Morris water maze test was used to observe the spatial learning and memory capabilities of the neonatal rats. RESULTS: At 14 and 21 days post-modeling, numerous cells with nuclear shrinkage and rupture, as well as disordered arrangement of nerve fibers, were observed in the tissues around the lateral ventricles of the WMI group and the low dose group. Compared with the WMI group, the medium and high dose groups showed alleviated pathological changes; the arrangement of nerve fibers in the medium dose group was relatively more orderly compared with the high dose group. Compared with the WMI group, there was no significant difference in the expression levels of MBP and GFAP mRNA in the low dose group (P>0.05), while the expression levels of MBP mRNA increased and GFAP mRNA decreased in the medium and high dose groups. The expression level of MBP mRNA in the medium dose group was higher than that in the high dose group, and the expression level of GFAP mRNA in the medium dose group was lower than that in the high dose group (P<0.05). Compared with the WMI group, there was no significant difference in the protein expression of GFAP and NeuN in the low dose group (P>0.05), while the expression of NeuN protein increased and GFAP protein decreased in the medium and high dose groups. The expression of NeuN protein in the medium dose group was higher than that in the high dose group, and the expression of GFAP protein in the medium dose group was lower than that in the high dose group (P<0.05). Compared with the WMI group, there was no significant difference in the number of apoptotic cells in the low dose group (P>0.05), while the number of apoptotic cells in the medium and high dose groups was less than that in the WMI group, and the number of apoptotic cells in the medium dose group was less than that in the high dose group (P<0.05). Compared with the WMI group, there was no significant difference in the escape latency time in the low dose group (P>0.05); starting from the third day of the latency period, the escape latency time in the medium dose group was less than that in the WMI group (P<0.05). The medium and high dose groups crossed the platform more times than the WMI group (P<0.05). CONCLUSIONS: Low dose hUC-MSCs may yield unsatisfactory repair effects on WMI in neonatal rats, while medium and high doses of hUC-MSCs have significant repair effects, with the medium dose demonstrating superior efficacy.


Assuntos
Animais Recém-Nascidos , Transplante de Células-Tronco Mesenquimais , Ratos Sprague-Dawley , Cordão Umbilical , Substância Branca , Animais , Ratos , Humanos , Cordão Umbilical/citologia , Substância Branca/patologia , Substância Branca/metabolismo , Proteína Glial Fibrilar Ácida/metabolismo , Proteína Glial Fibrilar Ácida/genética , Proteína Glial Fibrilar Ácida/análise , Células-Tronco Mesenquimais , Proteína Básica da Mielina/genética , Proteína Básica da Mielina/análise , Proteína Básica da Mielina/metabolismo , Masculino , Apoptose , Feminino , RNA Mensageiro/análise , RNA Mensageiro/metabolismo
9.
Plant Biotechnol J ; 21(4): 839-853, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36597709

RESUMO

Phased, small interfering RNAs (phasiRNAs) are important for plant anther development, especially for male sterility. PhasiRNA biogenesis is dependent on genes like RNA polymerase 6 (RDR6), DICER-LIKE 4 (DCL4), or DCL5 to produce 21- or 24 nucleotide (nt) double-strand small RNAs. Here, we generated mutants of DCL4, DCL5 and RDR6 using CRISPR/Cas9 system and studied their effects on plant reproductive development and phasiRNA production in wheat. We found that RDR6 mutation caused sever consequence throughout plant development starting from seed germination and the dcl4 mutants grew weaker with thorough male sterility, while dcl5 plants developed normally but exhibited male sterility. Correspondingly, DCL4 and DCL5, respectively, specified 21- and 24-nt phasiRNA biogenesis, while RDR6 contributed to both. Also, the three key genes evolved differently in wheat, with TaDCL5-A/B becoming non-functioning and TaRDR6-A being lost after polyploidization. Furthermore, we found that PHAS genes (phasiRNA precursors) identified via phasiRNAs diverged rapidly among sub-genomes of polyploid wheat. Despite no similarity being found among phasiRNAs of grasses, their targets were enriched for similar biological functions. In light of the important roles of phasiRNA pathways in gametophyte development, genetic dissection of the function of key genes may help generate male sterile lines suitable for hybrid wheat breeding.


Assuntos
Infertilidade Masculina , Triticum , Masculino , Humanos , Triticum/genética , Triticum/metabolismo , Sistemas CRISPR-Cas/genética , Melhoramento Vegetal , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , RNA Interferente Pequeno/genética , Mutagênese/genética , Plantas/genética , Infertilidade Masculina/genética , RNA de Plantas/genética , Regulação da Expressão Gênica de Plantas
10.
J Virol ; 96(22): e0147322, 2022 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-36342433

RESUMO

Transmissible gastroenteritis virus (TGEV) is member of the family Coronaviridae and mainly causes acute diarrhea. TGEV infection is characterized by vomiting, watery diarrhea, and severe dehydration, resulting in high mortality rates in neonatal piglets. TGEV infection symptoms are related to an imbalance of sodium absorption in small intestinal epithelial cells; however, the etiology of sodium imbalance diarrhea caused by TGEV remains unclear. In this study, we performed transcriptomic analysis of intestinal tissues from infected and healthy piglets and observed that the expression of NHE3, encoding Na+/H+ exchanger 3 (NHE3), the main exchanger of electroneutral sodium in intestinal epithelial cells, was significantly reduced upon TGEV infection. We also showed that specific inhibition of intestinal NHE3 activity could lead to the development of diarrhea in piglets. Furthermore, we revealed an interaction between TGEV N protein and NHE3 near the nucleus. The binding of TGEV N to NHE3 directly affected the expression and activity of NHE3 on the cell surface and affected cellular electrolyte absorption, leading to diarrhea. Molecular docking and computer-aided screening techniques were used to screen for the blocker of the interaction between TGEV N and NHE3, which identified irinotecan. We then demonstrated that irinotecan was effective in relieving TGEV-induced diarrhea in piglets. These findings provide new insights into the mechanism of TGEV-induced sodium imbalance diarrhea and could lead to the design of novel antiviral strategies against TGEV. IMPORTANCE A variety of coronaviruses have been found to cause severe diarrhea in hosts, including TGEV; however, the pathogenic mechanism is not clear. Therefore, prompt determination of the mechanism and identification of efficient therapeutic agents are required, both for public health reasons and for economic development. In this study, we demonstrated that NHE3 is the major expressed protein of NHEs in the intestine, and its expression decreased by nearly 70% after TGEV infection. Also, specific inhibition of intestinal NHE3 resulted in severe diarrhea in piglets. This demonstrated that NHE3 plays an important role in TGEV-induced diarrhea. In addition, we found that TGEV N directly regulates NHE3 expression and activity through protein-protein interaction, which is essential to promote diarrhea. Molecular docking and other techniques demonstrated that irinotecan could block the interaction and diarrhea caused by TGEV. Thus, our results provide a basis for the development of novel therapeutic agents against TGEV and guidance for the development of drugs for other diarrhea-causing coronaviruses.


Assuntos
Infecções por Coronavirus , Coronavirus , Vírus da Gastroenterite Transmissível , Animais , Suínos , Vírus da Gastroenterite Transmissível/fisiologia , Trocador 3 de Sódio-Hidrogênio/genética , Trocador 3 de Sódio-Hidrogênio/metabolismo , Proteínas do Nucleocapsídeo/metabolismo , Irinotecano , Simulação de Acoplamento Molecular , Diarreia/veterinária , Trocadores de Sódio-Hidrogênio/metabolismo , Coronavirus/metabolismo , Sódio/metabolismo
11.
Mol Phylogenet Evol ; 181: 107704, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36657625

RESUMO

The present study aimed to apply bioinformatic methods to analyze the structure of the S protein of human respiratory coronaviruses, including severe respiratory disease syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV), human coronavirus HKU1 (HCoV-HKU1), and severe respiratory disease syndrome coronavirus type 2 (SARS-CoV-2). We predicted and analyzed the physicochemical properties, hydrophilicity and hydrophobicity, transmembrane regions, signal peptides, phosphorylation and glycosylation sites, epitopes, functional domains, and motifs of the S proteins of human respiratory coronaviruses. All four S proteins contain a transmembrane region, which enables them to bind to host cell surface receptors. All four S proteins contain a signal peptide, phosphorylation sites, glycosylation sites, and epitopes. The predicted phosphorylation sites might mediate S protein activation, the glycosylation sites might affect the cellular orientation of the virus, and the predicted epitopes might have implications for the design of antiviral inhibitors. The S proteins of all four viruses have two structural domains, S1 (C-terminal and N-terminal domains) and S2 (homology region 1 and 2). Our bioinformatic analysis of the structural and functional domains of human respiratory coronavirus S proteins provides a basis for future research to develop broad-spectrum antiviral drugs, vaccines, and antibodies.


Assuntos
COVID-19 , Coronavírus da Síndrome Respiratória do Oriente Médio , Humanos , SARS-CoV-2 , Filogenia , Coronavírus da Síndrome Respiratória do Oriente Médio/metabolismo , Biologia Computacional
12.
Langmuir ; 39(6): 2312-2321, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36720635

RESUMO

Immobilization of enzymes within metal-organic frameworks is a powerful strategy to enhance the long-term usability of labile enzymes. However, the thus-confined enzymes suffer from the trade-off between enhanced stability and reduced activity because of the contradiction between the high crystallinity and the low accessibility. Here, by taking laccase and zeolitic imidazolate framework-8 (ZIF-8) as prototypes, we disclosed an observation that the stability-activity trade-off could be solved by controlling the defects via competitive coordination. Owing to the presence of competitive coordination between laccase and the ligand precursor of ZIF-8, there existed a three-stage process in the de novo encapsulation: nucleation-crystallization-recrystallization. Our results show that the biocomposites collected before the occurrence of recrystallization possessed both increased activity and enhanced stability. The findings here shed new light on the control of defects through the subtle use of competitive coordination, which is of great significance for the engineering application of biomacromolecules.


Assuntos
Estruturas Metalorgânicas , Zeolitas , Lacase , Enzimas Imobilizadas/química , Estruturas Metalorgânicas/química , Zeolitas/química
13.
Environ Sci Technol ; 57(15): 6188-6195, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-37011377

RESUMO

The coexistence of selenite (Se(IV)) and acetylacetone (AA) generated a synergistic effect on the growth inhibition of a bloom-forming cyanobacterium, Microcystis aeruginosa. The mechanism behind this phenomenon is of great significance in the control of harmful algal blooms. To elucidate the role of Se(IV) in this effect, the reactions in ternary solutions composed of Se(IV), AA (or two other similar hydrogen donors), and quinones, especially benzoquinone (BQ), were investigated. The transformation kinetic results demonstrate that Se(IV) played a catalytic role in the reactions between AA (or ascorbic acid) and quinones. By comparison with five other oxyanions (sulfite, sulfate, nitrite, nitrate, and phosphate) and two AA derivatives, the formation of an AA-Se(IV) complexation intermediate was confirmed as a key step in the accelerated reactions between BQ and AA. To our knowledge, this is the first report on Se(IV) as a catalyst for quinone-involved reactions. Since both quinones and Se are essential in cells and there are many other chemicals of similar electron-donating properties to that of AA, the finding here shed light on the regulation of electron transport chains in a variety of processes, especially the redox balances that are tuned by quinones and glutathione.


Assuntos
Microcystis , Ácido Selenioso/farmacologia , Benzoquinonas/farmacologia , Catálise
14.
BMC Infect Dis ; 23(1): 76, 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36747139

RESUMO

INTRODUCTION: Sepsis has the characteristics of high incidence, high mortality of ICU patients. Early assessment of disease severity and risk stratification of death in patients with sepsis, and further targeted intervention are very important. The purpose of this study was to develop machine learning models based on sequential organ failure assessment (SOFA) components to early predict in-hospital mortality in ICU patients with sepsis and evaluate model performance. METHODS: Patients admitted to ICU with sepsis diagnosis were extracted from MIMIC-IV database for retrospective analysis, and were randomly divided into training set and test set in accordance with 2:1. Six variables were included in this study, all of which were from the scores of 6 organ systems in SOFA score. The machine learning model was trained in the training set and evaluated in the validation set. Six machine learning methods including linear regression analysis, least absolute shrinkage and selection operator (LASSO), Logistic regression analysis (LR), Gaussian Naive Bayes (GNB) and support vector machines (SVM) were used to construct the death risk prediction models, and the accuracy, area under the receiver operating characteristic curve (AUROC), Decision Curve Analysis (DCA) and K-fold cross-validation were used to evaluate the prediction performance of developed models. RESULT: A total of 23,889 patients with sepsis were enrolled, of whom 3659 died in hospital. Three feature variables including renal system score, central nervous system score and cardio vascular system score were used to establish prediction models. The accuracy of the LR, GNB, SVM were 0.851, 0.844 and 0.862, respectively, which were better than linear regression analysis (0.123) and LASSO (0.130). The AUROCs of LR, GNB and SVM were 0.76, 0.76 and 0.67, respectively. K-fold cross validation showed that the average AUROCs of LR, GNB and SVM were 0.757 ± 0.005, 0.762 ± 0.006, 0.630 ± 0.013, respectively. For the probability threshold of 5-50%, LY and GNB models both showed positive net benefits. CONCLUSION: The two machine learning-based models (LR and GNB models) based on SOFA components can be used to predict in-hospital mortality of septic patients admitted to ICU.


Assuntos
Escores de Disfunção Orgânica , Sepse , Humanos , Adulto , Prognóstico , Estudos Retrospectivos , Teorema de Bayes , Unidades de Terapia Intensiva , Sepse/diagnóstico , Curva ROC , Mortalidade Hospitalar , Aprendizado de Máquina
15.
Eur J Nutr ; 62(7): 2991-3007, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37460822

RESUMO

PURPOSE: Prebiotics, including fructo-oligosaccharides (FOS) and galacto-oligosaccharides (GOS), stimulate beneficial gut bacteria and may be helpful for patients with Alzheimer's disease (AD). This study aimed to compare the effects of FOS and GOS, alone or in combination, on AD mice and to identify their underlying mechanisms. METHODS: Six-month-old APP/PS1 mice and wild-type mice were orally administered FOS, GOS, FOS + GOS or water by gavage for 6 weeks and then subjected to relative assays, including behavioral tests, biochemical assays and 16S rRNA sequencing. RESULTS: Through behavioral tests, we found that GOS had the best effect on reversing cognitive impairment in APP/PS1 mice, followed by FOS + GOS, while FOS had no effect. Through biochemical techniques, we found that GOS and FOS + GOS had effects on multiple targets, including diminishing Aß burden and proinflammatory IL-1ß and IL-6 levels, and changing the concentrations of neurotransmitters GABA and 5-HT in the brain. In contrast, FOS had only a slight anti-inflammatory effect. Moreover, through 16S rRNA sequencing, we found that prebiotics changed composition of gut microbiota. Notably, GOS increased relative abundance of Lactobacillus, FOS increased that of Bifidobacterium, and FOS + GOS increased that of both. Furthermore, prebiotics downregulated the expression levels of proteins of the TLR4-Myd88-NF-κB pathway in the colons and cortexes, suggesting the involvement of gut-brain mechanism in alleviating neuroinflammation. CONCLUSION: Among the three prebiotics, GOS was the optimal one to alleviate cognitive impairment in APP/PS1 mice and the mechanism was attributed to its multi-target role in alleviating Aß pathology and neuroinflammation, changing neurotransmitter concentrations, and modulating gut microbiota.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Camundongos , Animais , Eixo Encéfalo-Intestino , Prebióticos , RNA Ribossômico 16S/genética , Doenças Neuroinflamatórias , Disfunção Cognitiva/terapia , Doença de Alzheimer/terapia , Oligossacarídeos/farmacologia
16.
Phys Chem Chem Phys ; 25(7): 5785-5794, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36744652

RESUMO

High-quality Mn2-xCrxSb (x = 0.01, 0.04, and 0.1) epitaxial thin films were grown on SrTiO3 (STO) (001) single-crystal substrates using molecular beam epitaxy. Magnetotransport and magnetic measurements reveal that the x = 0.01 sample undergoes a quasi-ferrimagnetic (I) [Q-FIM(I)]-to-ferrimagnetic (II) [FIM(II)] spin reorientation (SR) transition and a giant magnetoresistance (MR) associated first-order ferrimagnetic(II)-to-antiferromagnetic (AFM) phase transition upon cooling, resulting in the AFM ground state with a weak in-plane net moment. Upon increasing the doping level from x = 0.01 to 0.1, both the SR transition and the first-order magnetic transition are suppressed. For x = 0.1, the former transition is suppressed, leaving only the Q-FIM(I)-to-AFM transition within the whole temperature region. TAFM-FIM shows almost similar changes upon the application of either in-plane or out-of-plane magnetic fields. TAFM-FIM values of the x = 0.01 and 0.04 samples are much higher than those of the Mn2-xCrxSb bulk with similar doping levels, which can be understood by the clamping effect from STO substrates. For each thin-film sample, the MR effect is observed near TAFM-FIM and disappears in the high temperature Q-FIM(I) phase and low temperature AFM phase, indicating that MR is related to the spin-dependent electron scattering during the first-order magnetic phase transition. Based on the magnetotransport and magnetic data, a magnetic phase diagram is established for the Mn2-xCrxSb films in the low doping level region.

17.
Phys Chem Chem Phys ; 25(10): 7550, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36848140

RESUMO

Correction for 'Magnetotransport and magnetic properties of Cr-modified Mn2Sb epitaxial thin films' by Ting-Wei Chen et al., Phys. Chem. Chem. Phys., 2023, 25, 5785-5794, https://doi.org/10.1039/D2CP05442F.

18.
J Obstet Gynaecol Res ; 49(11): 2753-2760, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37614048

RESUMO

OBJECTIVE: To investigate the association between carbohydrate antigen 125 (CA125) level and adenomyosis treatment failure (TF) after uterine artery embolization (UAE). METHODS: We evaluated 224 patients with symptomatic adenomyosis who underwent UAE between January 2016 and December 2020. Improvements in dysmenorrhea and menorrhagia were assessed on the basis of symptom relief criteria. The factors associated with TF were investigated using a multivariate logistic regression model. Patients were analyzed for preoperative CA125 levels, postoperative CA125 levels, and the normalization of postoperative CA125 levels. Long-term symptom relief and quality of life after UAE were compared between the groups. RESULTS: During the 24-month follow-up, 50 patients (22.3%) experienced TF. Compared to patients in the non-TF group, those in the TF group had significantly higher preoperative and postoperative CA125 levels (p < 0.05). Multivariate analysis revealed that failure to normalize postoperative CA125 levels was independently associated with an increased risk of TF (34.7% vs. 8.5%, p < 0.001; hazard ratio 3.953, 95% confidence interval 1.567-9.973, p = 0.004). After a 3-month follow-up period, patients who normalized their CA125 levels were more likely to achieve complete necrosis on magnetic resonance imaging than those who did not (82.1% vs. 56.8%, p < 0.001). Normalization of postoperative CA125 levels was significantly associated with fewer symptoms and better quality of life 12 months after UAE (p < 0.05). CONCLUSIONS: Following UAE, normalization of postoperative CA125 levels, rather than absolute values, was the strongest predictive marker of TF.


Assuntos
Adenomiose , Embolização da Artéria Uterina , Neoplasias Uterinas , Feminino , Humanos , Adenomiose/cirurgia , Adenomiose/complicações , Embolização da Artéria Uterina/métodos , Qualidade de Vida , Resultado do Tratamento , Falha de Tratamento , Antígeno Ca-125 , Carboidratos , Neoplasias Uterinas/diagnóstico
19.
BMC Biotechnol ; 22(1): 30, 2022 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-36303174

RESUMO

BACKGROUND: An important conceptual advance in health and the environment has been recognized that enzymes play a key role in the green processing industries. Of particular interest, chitosanase is beneficial for recycling the chitosan resource and producing chitosan oligosaccharides. Also, chitosan gene expression and molecular characterization will promote understanding of the biological function of bacterial chitosanase as well as explore chitosanase for utilizing chitosan resources. RESULTS: A chitosanase-producing bacterium TY24 was isolated and identified as Bacillus cereus. Moreover, the chitosanase gene was cloned and expressed in Escherichia coli. Sequence analysis reveals that the recombinant chitosanase (CHOE) belongs to the glycoside hydrolases 8 family. The purified CHOE has a molecular weight of about 48 kDa and the specific activity of 1150 U/mg. The optimal pH and temperature of CHOE were 5.5 and 65 °C, respectively. The enzyme was observed stable at the pH range of 4.5-7.5 and the temperature range of 30-65 °C. Especially, the half-life of CHOE at 65 °C was 161 min. Additionally, the activity of CHOE was remarkably enhanced in the presence of Mn2+, Cu2+, Mg2+ and K+, beside Ca2+ at 5 mM. Especially, the activity of CHOE was enhanced to more than 120% in the presence of 1% of various surfactants. CHOE exhibited the highest substrate specificity toward colloid chitosan. CONCLUSION: A bacterial chitosanase was cloned from B. cereus and successfully expressed in E. coli (BL21) DE3. The recombinant enzyme displayed good stability under acid pH and high-temperature conditions.


Assuntos
Bacillus cereus , Quitosana , Bacillus cereus/genética , Bacillus cereus/metabolismo , Quitosana/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Glicosídeo Hidrolases/química , Clonagem Molecular , Concentração de Íons de Hidrogênio
20.
Environ Sci Technol ; 56(13): 9683-9692, 2022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35696645

RESUMO

The regulation of photosynthetic machinery with a nonoxidative approach is a powerful but challenging strategy for the selective inhibition of bloom-forming cyanobacteria. Acetylacetone (AA) was recently found to be a target-selective cyanocide for Microcystis aeruginosa, but the cause and effect in the studied system are still unclear. By recording of the chemical fingerprints of the cells at two treatment intervals (12 and 72 h with 0.1 mM AA) with omics assays, the molecular mechanism of AA in inactivating Microcystis aeruginosa was elucidated. The results clearly reveal the effect of AA on ferredoxin and the consequent effects on the physiological and biochemical processes of Microcystis aeruginosa. In addition to its role as an electron acceptor of photosystem I, ferredoxin plays pivotal roles in the assimilation of nitrogen in cyanobacterial cells. The effect of AA on ferredoxin and on nonheme iron of photosystem II first cut off the photosynthetic electron transfer flow and then interrupted the synthesis of adenosine triphosphate (ATP) and reduced nicotinamide adenine dinucleotide phosphate (NADPH), which ultimately might affect carbon fixation and nitrogen assimilation metabolisms. The results here provide missing pieces in the current knowledge on the selective inhibition of cyanobacteria, which should shed light on the better control of harmful blooms.


Assuntos
Cianobactérias , Microcystis , Carbono , Elétrons , Ferredoxinas , Nitrogênio , Pentanonas
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