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1.
J Fungi (Basel) ; 10(5)2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38786685

RESUMO

Camellia oleifera is a woody, edible-oil plant native to China. Anthracnose is the major disease of Ca. oleifera, and Colletotrichum fructicola is the main epidemic pathogen. Our previous research indicated that CfHac1 (homologous to ATF/CREB1) and CfGcn5 (general control nonderepressible 5, Gcn5) are integral to key cellular processes that govern fungal development and pathogenesis. Further transcriptomic analyses of the CfHac1 and CfGcn5 mutants, particularly under conditions of endoplasmic reticulum (ER) stress, hold the potential to unveil additional genes implicated in this critical cellular response. We identified all OST/PMT (oligosaccharyltransferase/Protein O-Mannosyltransferases) genes in C. fructicola and analyzed their expression levels. To elucidate novel glycosylation-related genes that may be important for the virulence of C. fructicola, we took an unbiased transcriptomic approach comparing wild-type and the ∆Cfhac1 mutant. Notably, all OST/PMT genes were induced by dithiothreitol and down-regulated in the ΔCfhac1 mutant, yet only the CfPMT4 (Protein O-Mannosyltransferases 4) gene (A04626) was unaffected in the ΔCfgcn5. The results of targeted gene deletion experiments indicate that CfPMT4 plays a crucial role in both vegetative growth and conidiation. Additionally, our investigation revealed that the ΔCfpmt4 exhibits deficiencies in appressorium formation, as well as in its response to cell wall integrity and endoplasmic reticulum stresses. Furthermore, the mutant displayed impaired glycogen metabolism, which may contribute to reduced penetration ability. Overall, CfPmt4, an O-mannosyltransferase, controls the growth, development, and pathogenicity of Colletotrichum fructicola. Understanding the function of the CfPMT4 homolog could provide a potential molecular target for controlling Ca. oleifera anthracnose.

2.
Front Oncol ; 14: 1324392, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38567153

RESUMO

Background: Significant advancements in systemic treatment for hepatocellular carcinoma have been made in recent years. However, the optimal timing of systemic treatment before or after surgery remains unknown. This study aims to evaluate the impact of sequencing systemic treatment and surgical intervention on the long-term prognosis of hepatocellular carcinoma patients. Methods: In our study, we analyzed data from patients diagnosed with primary liver cancer (2004-2015) extracted from the SEER database. Patients who underwent both systemic treatment and surgical intervention were selected, divided into preoperative and postoperative systemic therapy groups. The primary endpoint of the study is overall survival(OS), and the secondary endpoint is cancer-specific survival (CSS). Propensity score matching (PSM) reduced the influence of confounding factors, while Kaplan-Meier curves and a multivariable Cox proportional hazards model accounted for variables during survival analysis. Results: A total of 1918 eligible HCC patients were included, with 1406 cases in the preoperative systemic treatment group and 512 cases in the postoperative systemic treatment group. Survival analysis showed that both the preoperative group demonstrated longer median overall survival (OS) and median cancer-specific survival (CSS) before and after PSM. After conducting multivariate COX regression analysis with stepwise adjustment of input variables, the postoperative systemic treatment group continued to exhibit a higher risk of all-cause mortality (HR: 1.84, 95% CI: 1.55-2.1) and cancer-specific mortality (HR: 2.10, 95% CI: 1.73-2.54). Subgroup analysis indicated consistent results for overall survival (OS) across different subgroups. Conclusions: Hepatocellular carcinoma patients from the SEER database who received preoperative systemic therapy had superior OS and CSS compared to those who received postoperative systemic therapy.

3.
Clin Ther ; 46(3): 275-284, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38360447

RESUMO

PURPOSE: The co-existence of Parkinson disease (PD) and myasthenia gravis (MG) in an individual should be exceptionally rare. The purpose of this study was to systematically review the current literature regarding the therapeutic effect and side effects of pharmacotherapy on patients with PD and MG. METHODS: Five bioscience and engineering databases (MEDLINE via PubMed, Cochrane Library, Scopus, EMBASE, and China National Knowledge Infrastructure) were searched from inception through February 21, 2022. Case reports and case series studies investigating pharmacotherapy in patients with PD and MG were included. Procedures were followed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. The methodologic quality of included studies was evaluated by using the National Institutes of Health Quality Assessment Tool for Case Series Studies. FINDINGS: Sixteen case reports and 5 case series studies with 32 participants met the inclusion criteria. Eight studies were rated as good quality, 10 were fair quality, and 3 were poor quality. The side effects of pharmacotherapy for PD or MG led to another disease, indicating an imbalance between dopamine and acetylcholine within human bodies. IMPLICATIONS: When treating a patient who has PD or MG, health providers should be cautious about the occurrence of another disease. Timely treatment must rely on monitoring new symptoms as soon as the pharmacotherapy for PD or MG is initiated. Physical therapy may be helpful in decreasing the side effects of pharmacotherapy in patients with PD and MG. A new treatment pattern of pharmacotherapy + physical therapy for patients with PD and MG warrants further research. International Prospective Register of Systematic Reviews identifier: CRD42022308066.


Assuntos
Miastenia Gravis , Doença de Parkinson , Estados Unidos , Humanos , Doença de Parkinson/tratamento farmacológico , Miastenia Gravis/tratamento farmacológico , Pesquisa , China
4.
Phytomedicine ; 126: 155437, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38394735

RESUMO

BACKGROUND: In diabetic liver injury, nonalcoholic fatty liver disease (NAFLD) is the most prevalent chronic liver disease. Rutin is a bioflavonoid produced by the hydrolysis of glucosidases to quercetin. Its biological activities include lowering blood glucose, regulating insulin secretion, regulating dyslipidemia, and exerting anti-inflammatory effects have been demonstrated. However, its effect on diabetic NAFLD is rarely reported. PURPOSE: Our study aimed to investigate the protective effects of Rutin on diabetic NAFLD and potential pharmacological mechanism. METHODS: We used db/db mice as the animal model to investigate diabetic NAFLD. Oleic acid-treated (OA) HeLa cells were examined whether Rutin had the ability to ameliorate lipid accumulation. HepG2 cells treated with 30 mM/l d-glucose and palmitic acid (PA) were used as diabetic NAFLD in vitro models. Total cholesterol (TC) and Triglycerides (TG) levels were determined. Oil red O staining and BODIPY 493/503 were used to detect lipid deposition within cells. The indicators of inflammation and oxidative stress were detected. The mechanism of Rutin in diabetic liver injury with NAFLD was analyzed using RNA-sequence and 16S rRNA, and the expression of fat-synthesizing proteins in the 5' adenosine monophosphate-activated protein kinase (AMPK) pathway was investigated. Compound C inhibitors were used to further verify the relationship between AMPK and Rutin in diabetic NAFLD. RESULTS: Rutin ameliorated lipid accumulation in OA-treated HeLa. In in vitro and in vivo models of diabetic NAFLD, Rutin alleviated lipid accumulation, inflammation, and oxidative stress. 16S analysis showed that Rutin could reduce gut microbiota dysregulation, such as the ratio of Firmicutes to Bacteroidetes. RNA-seq showed that the significantly differentially genes were mainly related to liver lipid metabolism. And the ameliorating effect of Rutin on diabetic NAFLD was through AMPK/SREBP1 pathway and the related lipid synthesis proteins was involved in this process. CONCLUSION: Rutin ameliorated diabetic NAFLD by activating the AMPK pathway and Rutin might be a potential new drug ingredient for diabetic NAFLD.


Assuntos
Diabetes Mellitus , Hepatopatia Gordurosa não Alcoólica , Humanos , Camundongos , Animais , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Metabolismo dos Lipídeos , Proteínas Quinases Ativadas por AMP/metabolismo , Rutina/farmacologia , Células HeLa , RNA Ribossômico 16S , Fígado , Inflamação/metabolismo , Dieta Hiperlipídica/efeitos adversos , Lipídeos , Camundongos Endogâmicos C57BL
5.
PLoS One ; 19(2): e0298456, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38359015

RESUMO

INTRODUCTION: Alcohol intent (the susceptibility to initiating alcohol use) and alcohol sips (the initiation of alcohol) in youth are a multifactorial puzzle with many components. This research aims to examine the connection between genetic and environmental factors across sex, race and ethnicity. METHODS: Data was obtained from the twin hub of the Adolescent Brain Cognitive Development (ABCD) study at baseline (2016-2018). Variance component models were conducted to dissect the additive genetic (A), common (C) and unique environmental (E) effects on alcohol traits. The proportion of the total alcohol phenotypic variation attributable to additive genetic factors is reported as heritability (h2). RESULTS: The sample (n = 1,772) included an approximately equal male-female distribution. The 886 same-sex twin pairs were 60.4% dizygotic (DZ), 39.6% monozygotic (MZ), 65.4% non-Hispanic Whites, 13.9% non-Hispanic Blacks, 10.8% of Hispanics with a mean age of 121.2 months. Overall, genetic predisposition was moderate for alcohol intent (h2 = 28%, p = .006) and low for alcohol initiation (h2 = 4%, p = 0.83). Hispanics (h2 = 53%, p < .0001) and Blacks (h2 = 48%, p < .0001) demonstrated higher alcohol intent due to additive genetic factors than Whites (h2 = 34%, p < .0001). Common environmental factors explained more variation in alcohol sips in females (c2 = 63%, p = .001) than in males (c2 = 55%, p = .003). Unique environmental factors largely attributed to alcohol intent, while common environmental factors explained the substantial variation in alcohol initiation. CONCLUSION: Sex and racial/ethnic disparities in genetic and environmental risk factors for susceptibility to alcohol initiation can lead to significant health disparities. Certain populations may be at greater risk for alcohol use due to their genetic and ecological factors at an early age.


Assuntos
Consumo de Bebidas Alcoólicas , Etnicidade , Grupos Raciais , Adolescente , Criança , Feminino , Humanos , Masculino , Consumo de Bebidas Alcoólicas/genética , Etnicidade/genética , Gêmeos
6.
Chin Med ; 19(1): 27, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38365794

RESUMO

BACKGROUND: Diabetic kidney disease (DKD) is a prevalent complication of diabetes and the leading cause of end-stage renal disease. Recent evidence suggests that total flavonoids of Astragalus (TFA) has promising effects on diabetes; however, its influence on DKD and the underlying mechanism remains unclear. METHODS: In this study, we induced the DKD model using streptozotocin (STZ) in male C57BL/6J mice and utilized glomerular endothelial cell (GEC) lines for in vitro investigations. We constructed a network pharmacology analysis to understand the mechanism of TFA in DKD. The mechanism of TFA action on DKD was investigated through Western blot analysis and multi-immunological methods. RESULTS: Our findings revealed that TFA significantly reduced levels of urinary albumin (ALB). Network pharmacology and intracellular pathway experiments indicated the crucial involvement of the PI3K/AKT signaling pathway in mediating these effects. In vitro experiments showed that TFA can preserve the integrity of the glomerular filtration barrier by inhibiting the expression of inflammatory factors TNF-alpha and IL-8, reducing oxidative stress. CONCLUSION: Our findings demonstrated that TFA can ameliorates the progression of DKD by ameliorating renal fibrosis and preserving the integrity of the kidney filtration barrier. These results provide pharmacological evidence supporting the use of TFA in the treatment of kidney diseases.

7.
Endocr Res ; 49(1): 46-58, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37950485

RESUMO

Diabetes mellitus is a multifactorial metabolic disease, of which type 2 diabetes (T2D) is one of the most common. The complications of diabetes are far more harmful than diabetes itself. Type 2 diabetes complications include diabetic nephropathy (DN), diabetic heart disease, diabetic foot ulcers (DFU), diabetic peripheral neuropathy (DPN), and diabetic retinopathy (DR) et al. Many animal models have been developed to study the pathogenesis of T2D and discover an effective strategy to treat its consequences. In this sense, it is crucial to choose the right animal model for the corresponding diabetic complication. This paper summarizes and classifies the animal modeling approaches to T2D complications and provides a comprehensive review of their advantages and disadvantages. It is hopeful that this paper will provide theoretical support for animal trials of diabetic complications.


Assuntos
Diabetes Mellitus Tipo 2 , Pé Diabético , Nefropatias Diabéticas , Neuropatias Diabéticas , Animais , Diabetes Mellitus Tipo 2/complicações , Pé Diabético/complicações , Nefropatias Diabéticas/etiologia , Nefropatias Diabéticas/metabolismo , Neuropatias Diabéticas/etiologia , Neuropatias Diabéticas/metabolismo , Neuropatias Diabéticas/patologia , Modelos Animais , Fatores de Risco
8.
Tob Prev Cessat ; 9: 34, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38026821

RESUMO

INTRODUCTION: Nicotine-containing products (NCPs) such as electronic nicotine delivery systems (ENDS) are increasingly common throughout the landscape of youth use of nicotine-containing products (NCP), and have overtaken traditional cigarette smoking modalities. This study seeks to examine the genetic and environmental influences on liability for susceptibility and initiation of ENDS and other NCPs among US children. METHODS: Data were drawn from 886 monozygotic (MZ) and dizygotic (DZ) twin pairs aged 9-10 years in the Adolescent Brain & Cognitive Development (ABCD) study at the baseline during 2016-2018. Heritability (h2) measured the proportion of the total phenotypic variation attributable to genes. Variance component models were utilized to analyze influences from the common environment (c2) and unique environmental factors (e2), taking into account correlations within twin pairs. RESULTS: The national sample included 50% females, 69.5% of non-Hispanic Whites, 12.8% of non-Hispanic Blacks, and 11.6% of Hispanics, with a mean age of 121.5 months. The twin sets were 60% DZ and 40% MZ. Heritability was low for NCP susceptibility (h2=0) and moderate for NCP initiation (h2=39%, p=0.02). The variance associated with NCP susceptibility was primarily influenced by environmental factors, especially one's unique factors (c2=37%, p<0.0001 vs e2=63%, p<0.0001). In contrast, the variance associated with NCP initiation was split across common and unique environmental factors (c2=32%, p=0.02 vs e2=29%, p=0.02). CONCLUSIONS: In the era with ENDS use surging among youth, NCP initiation remains to be a heritable trait with joint influence from the environment. NCP susceptibility is largely influenced by environmental factors, especially unique environments. Continued assessment of gene × environment interaction can better inform future youth NCP interventions.

9.
Sheng Wu Gong Cheng Xue Bao ; 39(8): 3253-3272, 2023 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-37622359

RESUMO

As a branched chain amino acid, L-valine is widely used in the medicine and feed sectors. In this study, a microbial cell factory for efficient production of L-valine was constructed by combining various metabolic engineering strategies. First, precursor supply for L-valine biosynthesis was enhanced by strengthening the glycolysis pathway and weakening the metabolic pathway of by-products. Subsequently, the key enzyme in the L-valine synthesis pathway, acetylhydroxylate synthase, was engineered by site-directed mutation to relieve the feedback inhibition of the engineered strain. Moreover, promoter engineering was used to optimize the gene expression level of key enzymes in L-valine biosynthetic pathway. Furthermore, cofactor engineering was adopted to change the cofactor preference of acetohydroxyacid isomeroreductase and branched-chain amino acid aminotransferase from NADPH to NADH. The engineered strain C. glutamicum K020 showed a significant increase in L-valine titer, yield and productivity in 5 L fed-batch bioreactor, up to 110 g/L, 0.51 g/g and 2.29 g/(L‧h), respectively.


Assuntos
Corynebacterium glutamicum , Valina , Corynebacterium glutamicum/genética , Engenharia Metabólica , Aminoácidos de Cadeia Ramificada , Reatores Biológicos
10.
Macromol Rapid Commun ; 44(23): e2300338, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37585284

RESUMO

The molecular order and vertical component distribution are critical to enhance the charge transport in layer-by-layer (LbL) processed active layer. However, the excessive inter-diffusion between donor and acceptor layers during LbL processing irrepressibly reduces their ordered packing. Herein, a novel tactic to optimize the molecular order and vertical morphology of the active layer through suppressing the deep penetration of (5Z,5'Z)-5,5'-((7,7'-(4,4,9,9-tetraoctyl-4,9-dihydro-s-indaceno[1,2-b:5,6 -b']dithiophene-2,7-diyl)bis(benzo[c][1,2,5]thiadiazole-7,4-diyl))bis(methanylylidene)) bis(3-ethyl-2-thioxothiazolidin-4-one) (O-IDTBR) to poly(3-hexylthiophene) (P3HT) film during LbL processing is proposed. This is enabled by inducing the formation of P3HT nanofibers through ultraviolet (UV) irradiation and solution aging. During the LbL processing, these nanofibers with high crystallinity reduce the damage of O-IDTBR solution to P3HT film and restrict the penetration of O-IDTBR into P3HT matrix. As a result, the P3HT nanofibers are preserved and the degree of vertical phase separation is enlarged in the LbL-processed film. Meanwhile, the molecular order of both components is enhanced. The resulting morphology that featured as intertwined P3HT nanofibers/O-IDTBR network efficiently promotes charge transport and extraction, boosting the power conversion efficiency (PCE) of the devices from 6.70 ± 0.12% to 7.71 ± 0.10%.


Assuntos
Nanofibras , Tiadiazóis , Bandagens , Difusão , Raios Ultravioleta
11.
PLoS One ; 18(5): e0285694, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37220118

RESUMO

BACKGROUND: Adherence to antiretroviral therapy (ART) remains the main predictor of sustained HIV virologic suppression for people with HIV (PWH). Mail-order pharmacy services are often offered to patients as an alternative option to traditional pharmacy services. Some payers mandate ART to be dispensed from specific mail-order pharmacies regardless of patient choice complicating ART adherence for patients affected by social disparities. Yet, little is known about patient perspectives regarding mail-order mandates. METHODS: Eligible patients of the HIV program at University of Nebraska Medical Center with experience receiving ART from both a local and mail-order pharmacy were invited to complete a 20-question survey with three core sections: experiences/perspectives on local and mail-order pharmacy settings; pharmacy attributes rankings; and pharmacy preference. Paired t-tests and Mann-Whitney tests were used to compare the agreement scores of pharmacy attributes. RESULTS: Sixty patients (N = 146; 41.1%) responded to the survey. Mean age was 52 years. Most were male (93%) and White (83%). The majority of participants were on ART for HIV treatment (90%) and 60% were using mail-order pharmacies for their prescription services. Significant scoring differences (p<0.05) were observed for all pharmacy attributes favoring local pharmacies. Refilling ease was the most important attribute noted. More respondents (68%) preferred local pharmacies versus mail-order pharmacies. Payer associated mail-order pharmacy mandates were experienced by 78% with half believing the mandates impacted their medical care negatively. CONCLUSIONS: In this cohort study, respondents preferred local pharmacies compared to mail-order pharmacy for ART prescription services and noted ease of refilling as the most important pharmacy attribute. Two-thirds of respondents believed mail-order pharmacy mandates negatively affected their health. Insurance payers should consider the removal of mail-order pharmacy mandates to allow patient choice of pharmacy, which may help remove barriers to ART adherence and improve long-term health outcomes.


Assuntos
Assistência Farmacêutica , Farmácias , Farmácia , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Estudos de Coortes , Estudos Transversais , Antirretrovirais
12.
Heliyon ; 9(3): e14171, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36938470

RESUMO

Aim: Diabetic nephropathy (DN) is the primary cause of end-stage renal disease worldwide. Although etiology for DN is complex and still needs to be fully understood, lipid metabolism disorder is found to play a role in it. Previously, we found Yishen Huashi (YSHS) granule could inhibit diabetic damage and reduce level of microalbuminuria (mALB) in DN animals. To explore its role and mechanism in lipid metabolism under DN settings, this study was designed. Materials and methods: DN rats were induced by streptozotocin (STZ), HepG2 and CaCO2 cells were applied for in vitro study. Hematoxylin-Eosin (HE), periodic acid-Schiff (PAS) staining, and Transmission Electron Microscopy (TEM) were applied for histological observation; 16s Sequencing was used for intestinal microbiota composition analysis; western blotting (WB) and immunofluorescence were carried out for molecular biological study, and enzyme-linked immunosorbent assay (ELISA) was used for lipid determination. Results: YSHS administration significantly reduced levels of total cholesterol (TC), triglyceride (TG), and low-density lipoprotein (LDL-C), while increased level of high-density lipoprotein (HDL-C); meanwhile, histological changes and steatosis of the liver was ameliorated, integrity of the intestinal barrier was enhanced, and dysbacteriosis within intestinal lumen was ameliorated. Mechanism study found that YSHS modulated mitophagy within hepatocytes and inhibited mTOR/AMPK/PI3K/AKT signaling pathway. Conclusion: In conclusion, we found in the present study that YSHS administration could ameliorate lipid metabolism disorder in DN animals, and its modulation on intestinal-liver axis played a significant role in it.

13.
Phytomedicine ; 112: 154700, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36774842

RESUMO

BACKGROUND: Diabetic kidney disease (DKD) is a primary microvascular complication of diabetes. However, a complete cure for DKD has not yet been found. Although there is evidence that Rutin can delay the onset of DKD, the underlying mechanism remains unclear. PURPOSE: To investigate the renoprotective effect of Rutin in the process of DKD and to explore its potential molecular mechanisms. METHODS: Db/db mice and high glucose (HG)-induced human renal glomerular endothelial cells (GEnCs) were used as in vivo and in vitro models, respectively. Western blot (WB), Immunohistochemistry (IHC)and Immunofluorescence (IF) staining were used to identify the expression level of proteins associated with endothelial-to-mesenchymal transition (EndMT) and autophagy. Tandem Mass Tag (TMT)-based proteomics analysis was utilized to reveal the mechanism of Rutin in DKD. Transfection with small interfering RNA (siRNA) to reveal the role of histone deacetylase 1 (HDAC1) in HG-induced GEnCs. RESULTS: Following 8 weeks of Rutin administration, db/db mice's kidney function and structure significantly improved. In HG-induced GEnCs, activation of autophagy attenuates cellular EndMT. Rutin could alleviate EndMT and restore autophagy in vivo and in vitro models. Proteomics analysis results showed that HDAC1 significantly downregulated in the 200 mg/kg/d Rutin group compared with the db/db group. Transfection with si-HDAC1 in GEnCs partially blocked HG-induced EndMT and restored autophagy. Furthermore, Rutin inhibits the phosphorylation of the PI3K / AKT/ mTOR pathway. HDAC1 overexpression was suppressed in HG-induced GEnCs after using Rapamycin, a specific mTOR inhibitor, verifying the correlation between mTOR and HDAC1. CONCLUSION: Rutin alleviates EndMT by restoring autophagy through inhibiting HDAC1 via the PI3K/AKT/mTOR pathway in DKD.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , Camundongos , Animais , Humanos , Nefropatias Diabéticas/tratamento farmacológico , Nefropatias Diabéticas/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais , Células Endoteliais/metabolismo , Histona Desacetilase 1/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Autofagia
14.
Chemistry ; 29(18): e202203702, 2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-36656133

RESUMO

Construction of sub-5 nm long-range ordered structures through self-assembly has received increasing attention. Herein, a series of ODMS-based thermotropic liquid crystals (LCs) containing perylene diimide (PDI) were designed and synthesized. These LCs can form ordered nanostructures with periodic sizes around 5 nm including smectic J (SmJ), oblique columnar (Colob ), and hexagonal columnar (Colh ) phases with change in the volume fraction of ODMS, where the layer spacing of the SmJ phase is less than 5 nm. Thin films with parallel oriented nanolines with line width less than 5 nm can be obtained on PDMS-modified silicon substrates by spin-casting and simple thermal annealing processes. Moreover, owing to the strong π-π interaction between PDI cores, these nanolines are long-range ordered with uniaxial orientation in relatively large areas (1.5×1.5 µm2 ) with over 300 continuous microdomains without pre-patterning. These nanostructures provide the possibility of preparing nanotemplates by oxygen plasma etching.

15.
ACS Appl Mater Interfaces ; 14(39): 44685-44696, 2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36153967

RESUMO

The morphology with strong molecular packing order and gradient vertical composition distribution associated with efficient charge transport and collection is critical to achieve high performance in nonfullerene solar cells. However, the rapid solidification process of the active layer upon the fast removal of solvent usually results in a kinetically trapped state with undesired morphology. Herein, we proposed a strategy to extend the crystal growth time of the acceptor via a high-boiling-point additive that selectively dissolved the acceptor. This was enabled by adding dibenzyl ether (DBE) to the poly(3-hexylthiophene) (P3HT):O-IDTBR blend in chlorobenzene (CB) solution. The combination of the kinetic study by time-resolved ultraviolet-visible (UV-vis) absorption spectra and detailed morphological characterization allows us to correlate the crystallization kinetics with the microstructural transition. The results show that the crystal growth time of O-IDTBR increases from 3 to 60 s upon the addition of 0.75% DBE, leading to further evolution of the molecular order of O-IDTBR during the DBE-dominated drying period. Meanwhile, O-IDTBR has more time to migrate toward the substrate owing to the larger surface energy. In addition, the onset of the crystallization process of P3HT is brought forward from 8 to 6 s due to the reduced solvent quality, which favors P3HT to crystallize into a fibril network. As a result, an optimized morphology that features the enhanced molecular packing order of P3HT and O-IDTBR as well as the vertical compositional gradient of O-IDTBR is obtained. Devices based on the optimized blend show more balanced charge transport and suppressed bimolecular recombination, giving rise to an improved power conversion efficiency (PCE) from 4.29 ± 0.04 to 7.30 ± 0.12%.

16.
Nat Plants ; 8(7): 828-839, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35851622

RESUMO

At present, a cooperative process hypothesis is used to explain the supply of enzyme (class III peroxidases and/or laccases) and substrates during lignin polymerization. However, it remains elusive how xylem cells meet the needs of early lignin rapid polymerization during secondary cell wall formation. Here we provide evidence that a mitochondrial ascorbate peroxidase (PtomtAPX) is responsible for autonomous lignification during the earliest stage of secondary cell wall formation in Populus tomentosa. PtomtAPX was relocated to cell walls undergoing programmed cell death and catalysed lignin polymerization in vitro. Aberrant phenotypes were caused by altered PtomtAPX expression levels in P. tomentosa. These results reveal that PtomtAPX is crucial for catalysing lignin polymerization during the early stages of secondary cell wall formation and xylem development, and describe how xylem cells provide autonomous enzymes needed for lignin polymerization during rapid formation of the secondary cell wall by coupling with the programmed cell death process.


Assuntos
Populus , Regulação da Expressão Gênica de Plantas , Lignina , Peroxidase/genética , Peroxidase/metabolismo , Peroxidases/genética , Peroxidases/metabolismo , Xilema/metabolismo
17.
Nat Commun ; 13(1): 2663, 2022 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-35562359

RESUMO

Recent studies have suggested that transcriptional protein condensates (or clusters) may play key roles in gene regulation and cell fate determination. However, it remains largely unclear how the gene regulation function is quantitatively tuned by transcription factor (TF) clustering and whether TF clustering may confer emergent behaviors as in cell fate control systems. Here, to address this, we construct synthetic TFs whose clustering behavior can be chemically controlled. Through single-parameter tuning of the system (i.e., TF clustering propensity), we provide lines of evidence supporting the direct transcriptional activation and amplification of target genes by TF clustering. Single-gene imaging suggests that such amplification results from the modulation of transcriptional dynamics. Importantly, TF clustering propensity modulates the gene regulation function by significantly tuning the effective TF binding affinity and to a lesser extent the ultrasensitivity, contributing to bimodality and sustained response behavior that are reminiscent of canonical cell fate control systems. Collectively, these results demonstrate that TF clustering can modulate the gene regulation function to enable emergent behaviors, and highlight the potential applications of chemically controlled protein clustering.


Assuntos
Regulação da Expressão Gênica , Fatores de Transcrição , Análise por Conglomerados , Fenótipo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Ativação Transcricional
18.
RSC Adv ; 12(10): 5732-5742, 2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-35424534

RESUMO

GPR120, also called FFAR4, is preferentially expressed in the intestines, and can be stimulated by long-chain free fatty acids to increase the secretion of glucagon-like peptide-1 (GLP-1) from intestinal endocrine cells. It is known that GLP-1, as an incretin, can promote the insulin secretion from pancreatic cells in a glucose-dependent manner. Therefore, GPR120 is a potential drug target to treat type 2 diabetes. In this study, thiazolidinedione derivatives were found to be novel potent GPR120 agonists. Compound 5g, with excellent agonistic activity, selectivity, and metabolic stability, improved oral glucose tolerance in normal C57BL/6 mice in a dose-dependent manner. Moreover, compound 5g exhibited anti-diabetic activity by promoting insulin secretion in diet-induced obese mice. In summary, compound 5g might be a promising drug candidate for the treatment of type 2 diabetes.

19.
Int J Mol Sci ; 23(6)2022 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-35328760

RESUMO

Chloroplasts are the most major producers of reactive oxygen species (ROS) during photosynthesis. However, the function of thylakoid ascorbate peroxidase (tAPX) in response to oxidative stress in wood trees is largely unknown. Our results showed that PtotAPX of Populus tomentosa could effectively utilize ascorbic acid (AsA) to hydrolyze hydrogen peroxide (H2O2) in vitro. The overexpression or antisense of PtotAPX (OX-PtotAPX or anti-PtotAPX, respectively) in Populus tomentosa plants did not significantly affect plant morphology during plant growth. When treated with methyl viologen (MV), the OX-PtotAPX plants exhibited less morphological damage under stress conditions compared to WT plants. OX-PtotAPX plants maintained lower H2O2 levels and malondialdehyde (MDA) contents, but more reduced AsA levels, a higher photosynthetic rate (Pn), and the maximal photochemical efficiency of PSII (Fv/Fm), whereas anti-PtotAPX plants showed the opposite phenotype. Furthermore, the activity of APX was slightly higher in OX-PtotAPX under normal growth conditions, and this activity significantly decreased after stress treatment, which was the lowest in anti-P. Based on these results, we propose that PtotAPX is important for protecting the photosynthetic machinery under severe oxidative stress conditions in P. tomentosa, and is a potential genetic resource for regulating the stress tolerance of woody plants.


Assuntos
Populus , Tilacoides , Ascorbato Peroxidases/metabolismo , Cloroplastos/metabolismo , Regulação da Expressão Gênica de Plantas , Peróxido de Hidrogênio/metabolismo , Estresse Oxidativo , Fotossíntese/genética , Plantas Geneticamente Modificadas/genética , Populus/genética , Populus/metabolismo , Tilacoides/metabolismo
20.
Biotechnol Bioeng ; 119(3): 983-993, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34936092

RESUMO

Tryptophan, an essential aromatic amino acid, is widely used in animal feed, food additives, and pharmaceuticals. Although sustainable and environmentally friendly, microbial tryptophan production from renewable feedstocks is limited by low biosynthesis and transport rates. Here, an Escherichia coli strain capable of efficient tryptophan production was generated by improving and balancing the supply of precursors and by engineering membrane transporters. Tryptophan biosynthesis was increased by eliminating negative regulatory factors, blocking competing pathways, and preventing tryptophan degradation. Promoter engineering balanced the supply of the precursors erythrose-4-phosphate and phosphoenolpyruvate, as well as the availability of serine. Finally, the engineering of tryptophan transporters prevented feedback inhibition and growth toxicity. Fed-batch fermentation of the final strain (TRP12) in a 5 L bioreactor produced 52.1 g·L-1 of tryptophan, with a yield of 0.171 g·g-1 glucose and productivity of 1.45 g·L-1 ·h-1 . The metabolic engineering strategy described here paves the way for high-performance microbial cell factories aimed at the production of tryptophan as well as other valuable chemicals.


Assuntos
Proteínas de Escherichia coli , Escherichia coli , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Fermentação , Engenharia Metabólica , Triptofano/metabolismo
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