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1.
Plant Sci ; 349: 112258, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39277049

RESUMO

Starch and proteins are main storage product to determine the appearance, cooking, texture, and nutritional quality of rice (Oryza sativa L.). OsNAC20 and OsNAC26, as pivotal transcription factors, redundantly regulate the expression of genes responsible for starch and protein synthesis in the rice endosperm. Any knockout of OsNAC20 or OsNAC26 did not result in visible endosperm defects. In this study, we had isolated and characterized a mutant named as floury endosperm25 (flo25). The caryopsis of the flo25 mutant exhibits a floury endosperm, accompanied by reductions in both the 1000-grain weight and grain length, as well as diminished levels of total starch and protein. Through map-based cloning, it was determined that FLO25 encodes a NAM, ATAF, and CUC (NAC) transcription factors, namely OsNAC26, with a lysine to asparagine substitution at position 98 in the flo25 mutant. Remarkably, lysine 98 is conserved across plants species, and this mutation does not alter the subcellular localization of OsNAC26 but significantly attenuates its transcriptional activity and its ability to activate downstream target genes. Furthermore, the mutant protein encoded by OsNAC26-flo25 could interact with OsNAC20, disrupting the native interaction between OsNAC20 proteins. Additionally, when lysine 98 is substituted with asparagine in OsNAC20, the resulting mutant protein, OsNAC20(K98N), similarly disrupts the interaction between OsNAC26 proteins. Collectively, these findings underscore the pivotal role of Lysine 98 (K) in modulating the transcriptional activity of NAC20/NAC26 within the rice endosperm.

2.
Int J Biol Macromol ; 279(Pt 3): 135324, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39241996

RESUMO

Wound healing in diabetic patients is often complicated by issues like inflammation, infection, bleeding, and fluid retention. To tackle these challenges, it is essential to create hydrogel dressings with anti-inflammatory, antibacterial, and antioxidative properties. This study aimed to synthesize Phlorizin-Liposomes (PL) through the thin-film dispersion method and integrate them into an oxidized sodium alginate (OSA) and carboxymethyl chitosan (CMCS) hydrogel scaffold, resulting in an OSA/CMCS/PL (PLOCS) composite hydrogel via a Schiff base reaction. Characterization of the composite was performed using FTIR, TEM, and SEM techniques. The research assessed the swelling behavior, antibacterial effectiveness, and biocompatibility of the PLOCS composite hydrogel, while also investigating how PLOCS facilitates diabetic wound healing. The results demonstrated that PLOCS effectively controls drug release, possesses favorable swelling and degradation characteristics, and shows significant antioxidative properties along with in vitro biocompatibility. Histological analysis confirmed that PLOCS supports the proliferation of healthy epithelial tissue and collagen production. Western blotting indicated that PLOCS diminishes inflammation by inhibiting the TLR4/NF-κB/MyD88 pathway and activates Nrf2 to boost wound healing, increasing the levels of antioxidative enzymes such as HO-1, NQO1, and GCLC. In summary, PLOCS presents a promising new option for advanced wound dressings aimed at treating diabetic ulcers.

3.
Int J Hyperthermia ; 41(1): 2379983, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39013550

RESUMO

As the utilization of high-resolution imaging modalities, such as ultrasound, becomes increasingly prevalent, there has been a swift rise in the detection rates of malignant thyroid nodules (MTC). Surgery remains the cornerstone of standard treatment for these nodules. However, the advent and evolution of thermal ablation (TA) techniques, encompassing radiofrequency ablation, laser ablation, and microwave ablation, have emerged as a novel therapeutic avenue for patients with MTC, particularly for those deemed unsuitable for surgery due to high risks or for those who refuse surgery. Presently, TA has been validated as an efficacious and safe intervention for both benign thyroid nodules and a subset of MTC. An expanding body of research has been dedicated to broadening the applicability of TA, initially from recurrent thyroid cancer and lymph nodes to now encompass isolated papillary thyroid microcarcinomas (PTMC) alongside a comprehensive exploration into the expanded parameters such as size, number, and location of PTMC, and its applicability in other types of thyroid cancer. This review provides a detailed synthesis of the clinical evidence about the use of TA in the management of MTC, as endorsed by current guidelines. It further delves into the ongoing research efforts aimed at extending its indications and discusses the prospective implications and challenges of integrating TA into the clinical management paradigms for MTC.


Assuntos
Nódulo da Glândula Tireoide , Humanos , Nódulo da Glândula Tireoide/cirurgia , Técnicas de Ablação/métodos
4.
J Med Chem ; 67(11): 9431-9446, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38818879

RESUMO

Synthetic lethality has recently emerged as a new approach for the treatment of mutated genes that were previously considered undruggable. Targeting methionine adenosyltransferase 2A (MAT2A) in cancers with deletion of the methylthioadenosine phosphorylase (MTAP) gene leads to synthetic lethality and thus has attracted significant interest in the field of precise anticancer drug development. Herein, we report the discovery of a series of novel MAT2A inhibitors featuring a pyrazolo[3,4-c]quinolin-4-one skeleton based on structure-based drug design. Further optimization led to compound 39, which has a high potency for inhibiting MAT2A and a remarkable selectivity for MTAP-deleted cancer cell lines. Compound 39 has a favorable pharmacokinetic profile with high plasma exposure and oral bioavailability, and it exhibits significant efficacy in xenograft MTAP-depleted models. Moreover, 39 demonstrates excellent brain exposure with a Kpuu of 0.64 in rats.


Assuntos
Encéfalo , Desenho de Fármacos , Inibidores Enzimáticos , Metionina Adenosiltransferase , Metionina Adenosiltransferase/antagonistas & inibidores , Metionina Adenosiltransferase/metabolismo , Humanos , Animais , Relação Estrutura-Atividade , Ratos , Encéfalo/metabolismo , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacocinética , Inibidores Enzimáticos/síntese química , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Antineoplásicos/farmacocinética , Antineoplásicos/química , Antineoplásicos/síntese química , Camundongos , Masculino , Ratos Sprague-Dawley , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Exp Ther Med ; 27(6): 266, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38756909

RESUMO

Gestational hypertension (GH) is a common disorder during pregnancy that can cause adverse pregnancy outcomes. In the present study, magnesium sulfate (MgSO4) combined with labetalol was used for clinical treatment. Randomized controlled trial was conducted in 100 patients with GH, documented in the Department of Obstetrics and Gynecology (Taicang TCM Hospital) grouped into the experimental (Expt) and control (Ctrl) groups (n=50 cases/group). The Ctrl group was treated with MgSO4, whereas the Expt group was treated with MgSO4 + labetalol. The systolic blood pressure (SBP) and diastolic blood pressure (DBP) in the Expt group were not significantly different from those in the Ctrl group (P>0.05). By contrast, the SBP and DBP were significantly lower after treatment than those before treatment in both groups (P<0.05). Whole blood viscosity, plasma viscosity and hematocrit were significantly lower in the Expt group compared with those in the Ctrl group after treatment (P<0.05). High mobility group box-1 protein, homocysteine and serum cystatin C levels in the Expt group were also markedly lower than those in the Ctrl group after treatment (P<0.05). In the Expt group, the rate of spontaneous vaginal delivery was much higher, whereas the rates of cesarean section and postpartum hemorrhage were markedly lower than those in the Ctrl group (P<0.05). The occurrence of fetal intrauterine distress, placental abruption, neonatal asphyxia, premature birth and neonatal death were also significantly lower in the Expt group than those in the Ctrl group (P<0.05). In conclusion, MgSO4 + labetalol could improve inflammatory stress and the hemodynamics of patients with GH, and may have a marked antihypertensive effect. Thus, it may improve pregnancy outcome and reduce perinatal complications.

6.
J Biomater Sci Polym Ed ; 35(4): 519-534, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38265701

RESUMO

Considering the differences in pH between bacterial infection microenvironment and normal tissues, a series of pH-responsive drug-release amphiphilic polyurethane copolymers (DPU-g-PEG) have been prepared in this work. Fourier transform infrared (FT-IR) spectroscopy and 1H NMR was selected to detect the structure of the condensed polymers. The DPU-g-PEG amphiphilic copolymers could form stable micelles with a hydrophilic shell of polyethylene glycol (PEG) and a hydrophobic core of polylactic acid (PLA). We loaded a model drug called triclosan onto DPU-g-PEG micelles and studied how pH affects their particle size, Zeta potential, and drug release performance. The results revealed that when exposed to acidic conditions, the surface potential of DPU-g-PEG micelles changed, the micelles' particle size increased, and the drug release performance was significantly enhanced. These results suggested that the micelles prepared in this study can release more antibacterial substances at sites of bacterial infection. Meanwhile, we also investigated the impact of different ratios of soft and hard segments on the properties of micelles, and the results showed that the pH responsiveness of micelles was strongest when the ratio of soft segments (PLLA diol + PEG 2000): 1,6-hexamethylene diisocyanate (HDI): 2,6-Bis-(2-hydroxy-ethyl)-pyrrolo[3,4-f]isoindole-1,3,5,7-tetraone (DMA) = 1: 1.2: 0.2. Furthermore, the results of inhibition zone test, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) all confirmed the antibacterial activity of triclosan-load DPU-g-PEG micelles. In conclusion, the DPU-g-PEG micelles produced in this study have the potential to be used as intelligent drug delivery systems in the biomedical field.


Assuntos
Infecções Bacterianas , Triclosan , Humanos , Micelas , Poliuretanos/química , Portadores de Fármacos/química , Triclosan/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Polietilenoglicóis/química , Polímeros/química , Antibacterianos/farmacologia , Concentração de Íons de Hidrogênio
7.
Acta Pharmacol Sin ; 45(5): 1077-1092, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38267547

RESUMO

Sepsis, a life-threatening health issue, lacks effective medicine targeting the septic response. In China, treatment combining the intravenous herbal medicine XueBiJing with conventional procedures reduces the 28-day mortality of critically ill patients by modulating septic response. In this study, we identified the combined active constituents that are responsible for the XueBiJing's anti-sepsis action. Sepsis was induced in rats by cecal ligation and puncture (CLP). The compounds were identified based on their systemic exposure levels and anti-sepsis activities in CLP rats that were given an intravenous bolus dose of XueBiJing. Furthermore, the identified compounds in combination were assessed, by comparing with XueBiJing, for levels of primary therapeutic outcome, pharmacokinetic equivalence, and pharmacokinetic compatibility. We showed that a total of 12 XueBiJing compounds, unchanged or metabolized, circulated with significant systemic exposure in CLP rats that received XueBiJing. Among these compounds, hydroxysafflor yellow A, paeoniflorin, oxypaeoniflorin, albiflorin, senkyunolide I, and tanshinol displayed significant anti-sepsis activities, which involved regulating immune responses, inhibiting excessive inflammation, modulating hemostasis, and improving organ function. A combination of the six compounds, with the same respective doses as in XueBiJing, displayed percentage survival and systemic exposure in CLP rats similar to those by XueBiJing. Both the combination and XueBiJing showed high degrees of pharmacokinetic compatibility regarding interactions among the six active compounds and influences of other circulating XueBiJing compounds. The identification of XueBiJing's pharmacologically significant constituents supports the medicine's anti-sepsis use and provides insights into a polypharmacology-based approach to develop medicines for effective sepsis management.


Assuntos
Medicamentos de Ervas Chinesas , Ratos Sprague-Dawley , Sepse , Animais , Sepse/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/uso terapêutico , Medicamentos de Ervas Chinesas/farmacocinética , Masculino , Ratos , Administração Intravenosa
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 309: 123874, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38217992

RESUMO

Recognizing and quantifying enantiomers of chiral molecule is of great importance in chemical, biological and pharmaceutical fields. Herein, we presented one simple-yet-efficient method of sensing tyrosine (Tyr) enantiomers. In this sensing, silver triangular nanoplates (AgTNPs) were used as colorimetric probes. L-Tyr quickly induced the color of AgTNPs solution to change from dark blue to light gray, whereas D-Tyr induced no change of the AgTNPs solution color. The obvious color change enables the naked eye to recognize Tyr enantiomer. The visual method was used to detect the enantiometric excess value of L-Tyr in the whole range (-100 % ∼ 100 %). This chiral sensing can be finished within 5 min using one simple ultraviolet-visible spectrometer or naked eye. Furthermore, the mechanism of this chiral sensing was explored. It was confirmed that this chiral sensing was based on AgTNPs' intrinsic chirality. This chiral sensing is rapid, simple, and low-cost, and has great potential for chiral determination of Tyr.


Assuntos
Colorimetria , Nanopartículas Metálicas , Tirosina/química , Prata/química , Nanopartículas Metálicas/química , Estereoisomerismo
9.
New Phytol ; 241(4): 1794-1812, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38135652

RESUMO

The SWI/SNF complex is guided to the promoters of designated genes by its co-operator to activate transcription in a timely and appropriate manner to govern development, pathogenesis, and stress responses in fungi. Nevertheless, knowledge of the complexes and their co-operator in phytopathogenic fungi is still fragmented. We demonstrate that the heat shock transcription factor SsHsf1 guides the SWI/SNF complex to promoters of heat shock protein (hsp) genes and antioxidant enzyme genes using biochemistry and pharmacology. This is accomplished through direct interaction with the complex subunit SsSnf5 under heat shock and oxidative stress. This results in the activation of their transcription and mediates histone displacement to maintain reactive oxygen species (ROS) homeostasis. Genetic results demonstrate that the transcription module formed by SsSnf5 and SsHsf1 is responsible for regulating morphogenesis, stress tolerance, and pathogenicity in Sclerotinia sclerotiorum, especially by directly activating the transcription of hsp genes and antioxidant enzyme genes counteracting plant-derived ROS. Furthermore, we show that stress-induced phosphorylation of SsSnf5 is necessary for the formation of the transcription module. This study establishes that the SWI/SNF complex and its co-operator cooperatively regulate the transcription of hsp genes and antioxidant enzyme genes to respond to host and environmental stress in the devastating phytopathogenic fungi.


Assuntos
Ascomicetos , Proteínas de Ligação a DNA , Fatores de Transcrição , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Ligação a DNA/metabolismo , Espécies Reativas de Oxigênio , Antioxidantes , Virulência , Proteínas de Choque Térmico/metabolismo , Homeostase
10.
Pathogens ; 12(11)2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-38003764

RESUMO

Catabolite control protein A (CcpA), an important global regulatory protein, is extensively found in S. aureus. Many studies have reported that CcpA plays a pivotal role in regulating the tricarboxylic acid cycle and pathogenicity. Moreover, the CcpA-knockout Staphylococcus aureus (S. aureus) in diabetic mice, compared with the wild-type, showed a reduced colonization rate in the tissues and organs and decreased inflammatory factor expression. However, the effect of CcpA-knockout S. aureus on the host's energy metabolism in a high-glucose environment and its mechanism of action remain unclear. S. aureus, a common and major human pathogen, is increasingly found in patients with obesity and diabetes, as recent clinical data reveal. To address this issue, we generated CcpA-knockout S. aureus strains with different genetic backgrounds to conduct in-depth investigations. In vitro experiments with high-glucose-treated cells and an in vivo model study with type 1 diabetic mice were used to evaluate the unknown effect of CcpA-knockout strains on both the glucose and lipid metabolism phenotypes of the host. We found that the strains caused an abnormal metabolic phenotype in type 1 diabetic mice, particularly in reducing random and fasting blood glucose and increasing triglyceride and fatty acid contents in the serum. In a high-glucose environment, CcpA-knockout S. aureus may activate the hepatic STAT5/PDK4 pathway and affect pyruvate utilization. An abnormal metabolic phenotype was thus observed in diabetic mice. Our findings provide a better understanding of the molecular mechanism of glucose and lipid metabolism disorders in diabetic patients infected with S. aureus.

11.
Med Chem Res ; 32(6): 1039-1062, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37305209

RESUMO

Small molecule drugs that covalently bind irreversibly to their target proteins have several advantages over conventional reversible inhibitors. They include increased duration of action, less-frequent drug dosing, reduced pharmacokinetic sensitivity, and the potential to target intractable shallow binding sites. Despite these advantages, the key challenges of irreversible covalent drugs are their potential for off-target toxicities and immunogenicity risks. Incorporating reversibility into covalent drugs would lead to less off-target toxicity by forming reversible adducts with off-target proteins and thus reducing the risk of idiosyncratic toxicities caused by the permanent modification of proteins, which leads to higher levels of potential haptens. Herein, we systematically review electrophilic warheads employed during the development of reversible covalent drugs. We hope the structural insights of electrophilic warheads would provide helpful information to medicinal chemists and aid in designing covalent drugs with better on-target selectivity and improved safety.

12.
Anal Chem ; 95(14): 6107-6114, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-36995160

RESUMO

Chiral nanoparticles are one of the research hotspots in the field of materials science, chemistry, and biology. Understanding and controlling the chirality of nanoparticles is one key step toward their use, but the origin of nanoparticles' chirality and its determinative factor are not well understood. In this work, we studied the chirality of gold nanoparticles (AuNPs) prepared through the conventional citrate reduction method. Unexpectedly, it was found that small AuNPs (∼13 nm) exhibited opposite chirality to the large AuNPs (>30 nm). The origin of the AuNPs chirality was revealed by comparing the crystal structure between small AuNPs and large AuNPs. It was proposed that the lattice orientation of fivefold-twinned AuNPs may be responsible for the intrinsic chirality of AuNPs. This work provides a deep mechanistic understanding of the intrinsic chirality of the AuNPs and will boost the development of the structure-controlled synthesis and application of chiral AuNPs and other chiral nanomaterials. Furthermore, based on the unexpected size effect, chiral AuNP probes were rationally constructed to improve the precision of chiral recognition.

13.
Acta Pharmacol Sin ; 44(2): 321-331, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35655094

RESUMO

Metabolic cardiomyopathy (MC) is characterized by intracellular lipid accumulation and utilizing fatty acids as a foremost energy source, thereby leading to excess oxidative stress and mitochondrial dysfunction. There is no effective therapy available yet. In this study we investigated whether defective mitophagy contributed to MC and whether urolithin A (UA), a naturally occurring microflora-derived metabolite, could protect against MC in experimental obese mice. Mice were fed high fat diet for 20 weeks to establish a diet-induced obese model. We showed that mitochondrial autophagy or mitophagy was significantly downregulated in the heart of experimental obese mice. UA (50 mg·kg-1·d-1, for 4 weeks) markedly activated mitophagy and ameliorated MC in obese mice by gavage. In PA-challenged H9C2 cardiomyocytes, UA (5 µM) significantly increased autophagosomes and decreased autolysosomes. Furthermore, UA administration rescued PINK1/Parkin-dependent mitophagy and relieved mitochondrial defects in the heart of obese mice, which led to improving cardiac diastolic function and ameliorating cardiac remodelling. In PA-challenged primarily isolated cardiomyocytes, both application of mitophagy inhibitor Mdivi-1 (15 µM) and silencing of mitophagy gene Parkin blunted the myocardial protective effect of UA. In summary, our data suggest that restoration of mitophagy with UA ameliorates symptoms of MC, which highlights a therapeutic potential of UA in the treatment of MC.


Assuntos
Cardiomiopatias , Mitofagia , Camundongos , Animais , Camundongos Obesos , Proteínas Quinases/metabolismo , Cardiomiopatias/metabolismo , Miócitos Cardíacos/metabolismo , Obesidade/complicações , Obesidade/tratamento farmacológico , Obesidade/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
14.
Pharmacology ; 108(1): 47-60, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36423586

RESUMO

INTRODUCTION: Luteolin is a flavonoid polyphenolic compound exerting broad pharmacological and medicinal properties. Diabetes-related obesity increases the total blood volume and cardiac output and may increase the myocardial hypertrophy progression. However, the mechanism of luteolin in diabetic myocardial hypertrophy remains uncertain. Therefore, this study aimed to evaluate whether luteolin improved diabetic cardiomyopathy (DCM) by inhibiting the proteasome activity. METHODS: Cardiomyopathy was induced in streptozotocin-treated diabetes mellitus (DM) and db/db mice. Luteolin (20 mg kg-1·day-1) was administrated via gavage for 12 weeks. In vitro, high glucose and high insulin (HGI, glucose at 25.5 mM and insulin at 0.1 µM) inducing primary neonatal rat cardiomyocytes (NRCMs) were treated with or without luteolin for 48 h. Echocardiography, reverse transcription quantitative polymerase chain reaction, histology, immunofluorescence, and Western blotting were conducted. Proteasome activities were also detected using a fluorescent peptide substrate. RESULTS: Luteolin administration significantly prevented the onset of cardiac hypertrophy, fibrosis, and dysfunction in type 1 DM (T1DM) and type 2 DM (T2DM). Compared with DCM mice, luteolin groups showed lower serum triglyceride and total cholesterol levels. Furthermore, luteolin attenuated HGI-induced myocardial hypertrophy and reduced atrial natriuretic factor mRNA level in NRCMs. Proteasome activities were inhibited by luteolin in vitro. Luteolin also reduces the proteasome subunit levels (PSMB) 1, PSMB2, and PSMB5 of the 20S proteasome, as well as proteasome-regulated particles (Rpt) 1 and Rpt4 levels of 19S proteasome. Furthermore, luteolin treatment increased protein kinase B (AKT) and GSK-3α/ß (inactivation of GSK-3) phosphorylation. The phosphorylation level of AMPK activity was also reversed after the treatment with luteolin in comparison with the HGI-treated group. CONCLUSION: This study indicates that luteolin protected against DCM in mice, including T1DM and T2DM, by upregulating phosphorylated protein AMPK and AKT/GSK-3 pathways while decreasing the proteasome activity. These findings suggest that luteolin may be a potential therapeutic agent for DCM.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Cardiomiopatias Diabéticas , Insulinas , Ratos , Camundongos , Animais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Quinase 3 da Glicogênio Sintase/efeitos adversos , Quinase 3 da Glicogênio Sintase/metabolismo , Luteolina/farmacologia , Luteolina/uso terapêutico , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/tratamento farmacológico , Proteínas Quinases Ativadas por AMP/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Complexo de Endopeptidases do Proteassoma/uso terapêutico , Transdução de Sinais , Cardiomiopatias Diabéticas/tratamento farmacológico , Cardiomiopatias Diabéticas/metabolismo , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/tratamento farmacológico , Glucose , Cardiomegalia/tratamento farmacológico , Cardiomegalia/prevenção & controle , Insulinas/efeitos adversos
15.
Front Plant Sci ; 13: 1008896, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36544873

RESUMO

Rapid dehydration of maize grain is one of the main characteristics of cultivar selection for mechanical grain harvest; however, the dominant driving forces and mechanisms of grain dehydration before physiological maturity remain disputable and obscure. This study compared the grain moisture content and dehydration rate of coated treatment (no surface evaporation) and control grains. Meanwhile, the xylem-mobile dye was infused from stem and cob, and its movement was observed in cob, ear-stalk and stem xylem. The development dynamics of husk, grain and cob were analyzed to determine the mechanism of grain dehydration. The results showed that, from grain formation to 5-10 days before physiological maturity, the main driving force of grain dehydration of the early and middle-maturity maize cultivars was filling, followed by surface evaporation. In the dye movement experiment, the movement of the stem-infused xylem-mobile dye through the pedicel xylem was observed during but not after the grain formation period. Moreover, the cob-infused xylem-mobile dye moved to the ear- stalk and the stem via the xylem. There was a significantly positive correlation between grain filling rate and dehydration rate from grain formation to physiological maturity. According to these results, we proposed that in the grain dehydration phase driven by filling, the surplus water in the grain flows back to the cob via the pedicel xylem, of which some flowed back to the plant via the cob and ear- stalk xylem. This provides a new theoretical basis for selecting and breeding maize cultivars suitable for mechanical grain harvesting.

16.
J Pharm Anal ; 12(4): 664-682, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36105162

RESUMO

XueBiJing is an intravenous five-herb injection used to treat sepsis in China. The study aimed to develop a liquid chromatography-tandem mass spectrometry (LC-MS/MS)- or liquid chromatography-ultraviolet (LC-UV)-based assay for quality evaluation of XueBiJing. Assay development involved identifying marker constituents to make the assay therapeutically relevant and building a reliable one-point calibrator for monitoring the various analytes in parallel. Nine marker constituents from the five herbs were selected based on XueBiJing's chemical composition, pharmacokinetics, and pharmacodynamics. A selectivity test (for "similarity of response") was developed to identify and minimize interference by non-target constituents. Then, an intercept test was developed to fulfill "linearity through zero" for each analyte (absolute ratio of intercept to C response, <2%). Using the newly developed assays, we analyzed samples from 33 batches of XueBiJing, manufactured over three years, and found small batch-to-batch variability in contents of the marker constituents (4.1%-14.8%), except for senkyunolide I (26.5%).

17.
Nanoscale ; 14(31): 11179-11186, 2022 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-35904403

RESUMO

The performance of potassium (K)-ion batteries (KIBs) is not only dependent on electrode materials but also highly related to the electrolyte. In this work, we obtained a cobalt sulfide (CoS)-containing hybrid by the hydrothermal method and subsequent thermal treatment for K-ion storage. After ether-based electrolyte matching, the CoS-containing hybrid achieves a specific capacity of 229 mA h g-1 at 1 A g-1 after 300 cycles, and presents enhanced performance in the ether-based electrolyte. According to our measurement and calculation, the CoS-containing hybrid in the ether-based electrolyte promotes the formation of a highly anionic coordination solvated structure, which contributes to the enhancement of the stability of the electrolyte for K-ion storage. In addition, the strong coordination of anions also facilitates the rapid separation of the solvent during the potassiation process, which is also in favor of the decrease of the side reaction of the CoS@RGO hybrid for KIBs. We believe that our work will provide a new perspective on electrolyte engineering to boost the electrode material performance for K-ion storage.

18.
Polymers (Basel) ; 14(11)2022 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-35683870

RESUMO

As a new type of polymer, water-driven polyurethane (PU) has attracted increasing attention of researchers; however, with the popularization of its application, the following infection problems limit their applications, especially in the biomedical field. Herein, a series of novel cellulose nanocrystals (CNCs)-based PUs were first synthesized by chemical cross-linking CNCs with triblock copolymer polylactide-poly (ethylene glycol)-polylactide (CNC-PU). After covalent binding with tannic acid (TA-CNC-PU), the silver nanoparticles (Ag NPs) were further introduced into the material by a reduction reaction (Ag/TA-CNC-PU). Finally, the prepared serial CNCs-based PU nanocomposites were fully characterized, including the microstructure, water contact angle, water uptake, thermal properties as well as antibacterial activity. Compared with CNC-PU, the obtained TA-CNC-PU and Ag/TA-CNC-PU were capable of lower glass transition temperatures and improved thermal stability. In addition, we found that the introduction of tannic acid and Ag NPs clearly increased the material hydrophobicity and antibacterial activity. In particular, the Ag/TA-CNC-PU had a better antibacterial effect on E. coli, while TA-CNC-PU had better inhibitory effect on S. aureus over a 24 h time period. Therefore, these novel CNCs-based PUs may be more beneficial for thermal processing and could potentially be developed into a new class of smart biomaterial material with good antibacterial properties by adjusting the ratio of TA or Ag NPs in their structures.

19.
Diabetes ; 71(4): 795-811, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35043173

RESUMO

Methazolamide (MTZ), a carbonic anhydrase inhibitor, has been shown to inhibit cardiomyocyte hypertrophy and exert a hypoglycemic effect in patients with type 2 diabetes and diabetic db/db mice. However, whether MTZ has a cardioprotective effect in the setting of diabetic cardiomyopathy is not clear. We investigated the effects of MTZ in a mouse model of streptozotocin-induced type 1 diabetes mellitus (T1DM). Diabetic mice received MTZ by intragastric gavage (10, 25, or 50 mg/kg, daily for 16 weeks). In the diabetic group, MTZ significantly reduced both random and fasting blood glucose levels and improved glucose tolerance in a dose-dependent manner. MTZ ameliorated T1DM-induced changes in cardiac morphology and dysfunction. Mechanistic analysis revealed that MTZ blunted T1DM-induced enhanced expression of ß-catenin. Similar results were observed in neonatal rat cardiomyocytes (NRCMs) and adult mouse cardiomyocytes treated with high glucose or Wnt3a (a ß-catenin activator). There was no significant change in ß-catenin mRNA levels in cardiac tissues or NRCMs. MTZ-mediated ß-catenin downregulation was recovered by MG132, a proteasome inhibitor. Immunoprecipitation and immunofluorescence analyses showed augmentation of AXIN1-ß-catenin interaction by MTZ in T1DM hearts and in NRCMs treated with Wnt3a; thus, MTZ may potentiate AXIN1-ß-catenin linkage to increase ß-catenin degradation. Overall, MTZ may alleviate cardiac hypertrophy by mediating AXIN1-ß-catenin interaction to promote degradation and inhibition of ß-catenin activity. These findings may help inform novel therapeutic strategy to prevent heart failure in patients with diabetes.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Cardiomiopatias Diabéticas , Animais , Proteína Axina/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Cardiomiopatias Diabéticas/tratamento farmacológico , Cardiomiopatias Diabéticas/metabolismo , Cardiomiopatias Diabéticas/prevenção & controle , Glucose/metabolismo , Humanos , Metazolamida/metabolismo , Metazolamida/farmacologia , Metazolamida/uso terapêutico , Camundongos , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/metabolismo , Ratos , beta Catenina/metabolismo
20.
Chem Commun (Camb) ; 58(3): 427-430, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34897305

RESUMO

Rhombic dodecahedral gold nanoparticles (GNPs) are found to have inherent chirality and can be used as colorimetric probes for naked-eye recognition of histidine enantiomers. Our findings are helpful for developing new GNP-based chiral sensing systems through tuning of nanoparticle morphology.

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