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1.
Front Plant Sci ; 15: 1257882, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38567136

RESUMO

Introduction: An appropriate supply of ammonium (NH4+) in addition to nitrate (NO3-) can greatly improve plant growth and promote maize productivity. However, knowledge gaps exist regarding the mechanisms by which different nitrogen (N) fertilizer sources affect the enzymatic activity of nitrogen metabolism and non-structural carbohydrates during the post-anthesis period. Methods: A field experiment across 3-year was carried out to explore the effects of four nitrateammonium ratio (NO3-/NH4+ = 1:0 (N1), 1:1 (N2), 1:3 (N3), and 3:1 (N4)) on postanthesis dry matter (DM) and N accumulation, partitioning, transportation, and grain yield in maize. Results: NO3-/NH4+ ratio with 3:1 improved the enzymatic activity of N metabolism and non-structural carbohydrate accumulation, which strongly promoted the transfer of DM and N in vegetative organs to reproductive organs and improved the pre-anthesis DM and nitrogen translocation efficiency. The enzymatic activities of nitrate reductase, nitrite reductase, glutamine synthetase, glutamine oxoglutarate aminotransferase, and non-structural carbohydrate accumulation under N4 treatment were increased by 9.30%-32.82%, 13.19%-37.94%, 4.11%-16.00%, 11.19%-30.82%, and 14.89%-31.71% compared with the other treatments. Mixed NO3--N and NH4+-N increased the total DM accumulation at the anthesis and maturity stages, simultaneously decreasing the DM partitioning of stem, increasing total DM, DM translocation efficiency (DMtE), and contribution of pre-anthesis assimilates to the grain (CAPG) in 2015 and 2017, promoting the transfer of DM from stem to grain. Furthermore, the grain yield increased by 3.31%-9.94% (2015), 68.6%-26.30% (2016), and 8.292%-36.08% (2017) under the N4 treatment compared to the N1, N2, and N3 treatments. Conclusion: The study showed that a NO3-/NH4+ ratio of 3:1 is recommended for high-yield and sustainable maize management strategies in Northwestern China.

2.
Cell Stem Cell ; 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38593797

RESUMO

Many patient-derived tumor models have emerged recently. However, their potential to guide personalized drug selection remains unclear. Here, we report patient-derived tumor-like cell clusters (PTCs) for non-small cell lung cancer (NSCLC), capable of conducting 100-5,000 drug tests within 10 days. We have established 283 PTC models with an 81% success rate. PTCs contain primary tumor epithelium self-assembled with endogenous stromal and immune cells and show a high degree of similarity to the original tumors in phenotypic and genotypic features. Utilizing standardized culture and drug-response assessment protocols, PTC drug-testing assays reveal 89% overall consistency in prospectively predicting clinical outcomes, with 98.1% accuracy distinguishing complete/partial response from progressive disease. Notably, PTCs enable accurate prediction of clinical outcomes for patients undergoing anti-PD1 therapy by combining cell viability and IFN-γ value assessments. These findings suggest that PTCs could serve as a valuable preclinical model for personalized medicine and basic research in NSCLC.

3.
Int J Nanomedicine ; 19: 3217-3232, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38596410

RESUMO

Background: Skin wounds are a prevalent issue that can have severe health consequences if not treated correctly. Nanozymes offer a promising therapeutic approach for the treatment of skin wounds, owing to their advantages in regulating redox homeostasis to reduce oxidative damage and kill bacteria. These properties make them an effective treatment option for skin wounds. However, most of current nanozymes lack the capability to simultaneously address inflammation, oxidative stress, and bacterial infection during the wound healing process. There is still great potential for nanozymes to increase their therapeutic functional diversity and efficacy. Methods: Herein, copper-doped hollow mesopores cerium oxide (Cu-HMCe) nanozymes with multifunctional of antioxidant, antimicrobial and pro-vascularity is successfully prepared. Cu-HMCe can be efficiently prepared through a simple and rapid solution method and displays sound physiological stability. The biocompatibility, pro-angiogenic, antimicrobial, and antioxidant properties of Cu-HMCe were assessed. Moreover, a full-thickness skin defect infection model was utilized to investigate the wound healing capacity, as well as anti-inflammatory and pro-angiogenic properties of nanozymes in vivo. Results: Both in vitro and in vivo experiments have substantiated Cu-HMCe's remarkable biocompatibility. Moreover, Cu-HMCe possesses potent antioxidant enzyme-like catalytic activity, effectively clearing DPPH radicals (with a scavenging rate of 80%), hydroxyl radicals, and reactive oxygen species. Additionally, Cu-HMCe exhibits excellent antimicrobial and pro-angiogenic properties, with over 70% inhibition of both E. coli and S. aureus. These properties collectively promote wound healing, and the wound treated with Cu-HMCe achieved a closure rate of over 90% on the 14th day. Conclusion: The results indicate that multifunctional Cu-HMCe with antioxidant, antimicrobial, and pro-angiogenic properties was successfully prepared and exhibited remarkable efficacy in promoting wound healing. This nanozymes providing a promising strategy for skin repair.


Assuntos
Anti-Infecciosos , Antioxidantes , Antioxidantes/farmacologia , Cobre/farmacologia , Escherichia coli , Staphylococcus aureus , Anti-Infecciosos/farmacologia , Antibacterianos/farmacologia , Hidrogéis
4.
J Magn Reson Imaging ; 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38440902

RESUMO

BACKGROUND: Extracorporeal membrane oxygenation (ECMO), has partly improved congenital diaphragmatic hernia (CDH) outcomes, yet the overall morbidity and mortality remain high. Existing prenatal indicators for CDH fetuses are operator-dependent, time-consuming, or less accurate, a new simple and accurate indicator to indicate adverse events in CDH patients is needed. PURPOSE: To propose and assess the association of a new MRI parameter, the relative mediastinal displacement index (RMDI), with adverse events including in-hospital deaths or the need for ECMO in fetuses with isolated left CDH (iLCDH). STUDY TYPE: Retrospective analysis. SUBJECTS: One hundred thirty-nine fetuses were included in the iLCDH group (24 with adverse events and 115 without) and 257 fetuses were included in the control group from two centers in Guangzhou. FIELD STRENGTH/SEQUENCE: 3.0 T, T2WI-TRUFI; 1.5 T, T2WI-FIESTA. ASSESSMENT: Three operators independently measured the → DL $$ \underset{\mathrm{DL}}{\to } $$ , → DR $$ \underset{\mathrm{DR}}{\to } $$ , and DH on the axial images. The calculation formula of the RMDI was ( → DL $$ \underset{\mathrm{DL}}{\to } $$ + → DR $$ \underset{\mathrm{DR}}{\to } $$ )/DH . STATISTICAL TESTS: The independent sample t test, Mann-Whitney U test, Chi-square test, Chi-square test continuity correction, Fisher's test, linear regression analysis, logistic regression analysis, intraclass correlation coefficient, receiver operating characteristic curve analysis, and Delong test. A P value <0.05 was considered statistically significant. RESULTS: The RMDI did not change with gestational age in the iLCDH group (with [P = 0.189] and without [P = 0.567] adverse events) and the control group (P = 0.876). There were significant differences in RMDI between the iLCDH group (0.89 [0.65, 1.00]) and the control group (-0.23 [-0.34, -0.16]). In the iLCDH group, RMDI was the only indicator left for indicating adverse events, and the best cutoff value was 1.105. Moreover, there was a significant difference in diagnostic accuracy between the RMDI (AUC = 0.900) and MSA (AUC = 0.820), LHR (AUC = 0.753), o/e LHR (AUC = 0.709), and o/e TFLV (AUC = 0.728), respectively. DATA CONCLUSION: The RMDI is expected to be a simple and accurate tool for indicating adverse events in fetuses with iLCDH. EVIDENCE LEVEL: 4 TECHNICAL EFFICACY: Stage 1.

5.
ACS Biomater Sci Eng ; 10(4): 2414-2425, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38446137

RESUMO

Bone defects are a common and challenging orthopedic problem with poor self-healing ability and long treatment cycles. The difficult-to-heal bone defects cause a significant burden of medical expenses on patients. Currently, biomaterials with mechanical stability, long-lasting action, and osteogenic activity are considered as a suitable way to effectively heal bone defects. Here, an injectable double network (DN) hydrogel prepared using physical and chemical cross-linking methods is designed. The first rigid network is constructed using methylpropenylated hyaluronic acid (HAMA), while the addition of chitosan oligosaccharide (COS) forms a second flexible network by physical cross-linking. The mesoporous silica nanoparticles (MSN) loaded with bone morphogenetic protein-4 (BMP-4) were embedded into DN hydrogel, which not only enhanced the mechanical stability of the hydrogel, but also slowly released BMP-4 to achieve long-term skull repair. The designed composite hydrogel showed an excellent compression property and deformation resistance. In vitro studies confirmed that the HAMA/COS/MSN@BMP-4 hydrogel had good biocompatibility and showed great potential in supporting proliferation and osteogenic differentiation of mouse embryo osteoblast precursor (MC3T3-E1) cells. Furthermore, in vivo studies confirmed that the DN hydrogel successfully filled and closed irregular skull defect wounds, effectively promoted bone regeneration, and significantly promoted bone repair compared with the control group. In addition, HAMA/COS/MSN@BMP-4 hydrogel precursor solution can quickly form hydrogel in situ at the wound by ultraviolet light, which can be applied to the closure and repair of wounds of different shapes, which provides the new way for the treatment of bone defects.


Assuntos
Hidrogéis , Nanopartículas , Camundongos , Animais , Humanos , Hidrogéis/farmacologia , Hidrogéis/química , Osteogênese , Dióxido de Silício/farmacologia , Proteína Morfogenética Óssea 2/química , Proteína Morfogenética Óssea 2/farmacologia , Crânio/cirurgia , Crânio/lesões , Nanopartículas/química
6.
Int Immunopharmacol ; 131: 111912, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38522140

RESUMO

Water-soluble rhamnogalacturonan-I enriched citrus pectin (WRP) has promising effect on antimicrobial defense. We aim to determine whether the modified acidic (A) or neutral (B) WRP solutions can improve intestinal microbial dysbiosis in burn-injured mice. Male Balb/c mice were gavaged with WRPs at 80, 160, 320 mg/kg. Body weight daily for 21 days before exposed to thermal injury of 15 % total body surface area and mortality was monitored. Mice with 80 mg/kg WRPs were also subjected to fecal DNAs and T cell metabonomics analysis, intestinal and plasma glucagon-like peptide 1 (GLP-1) detection, plasma defensin, immunoglobin and intestinal barrier examinations at 1 and 3d postburn (p.b.). Burn-induced mortality was only improved by low dose WRP-A (P = 0.039). Both WRPs could prevent the dysbiosis of gut microbiota in burn injury by reducing the expansion of inflammation-promoting bacteria. Both WRPs suppressed ileum GLP-1 production at 1d p.b. (P = 0.002) and plasma GLP-1 levels at 3d p.b. (P = 0.013). Plasma GLP-1 level correlated closely with ileum GLP-1 production (P = 0.019) but negatively with microbiota diversity at 1d p.b. (P = 0.003). Intestinal T cell number was increased by both WRPs in jejunum at 3d p.b. However, the exaggerated splenic T cell metabolism in burn injury was reversed by both WRPs at 1d p.b. The burn-increased plasma defensin ß1 level was only reduced by WRP-B. Similarly, the intestinal barrier permeability was only rescued by WRP-B at 1d p.b. WRP-A rather than WRP-B could reduce burn-induced mortality in mice by suppressing intestinal GLP-1 secretion, restoring gut microbiota dysbiosis and improving adaptive immune response.


Assuntos
Queimaduras , Microbioma Gastrointestinal , Pectinas , Camundongos , Masculino , Animais , Peptídeo 1 Semelhante ao Glucagon , Disbiose/tratamento farmacológico , Imunidade , Queimaduras/tratamento farmacológico , Queimaduras/metabolismo , Defensinas
7.
J Environ Manage ; 356: 120642, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38503227

RESUMO

The polysilicate aluminum ferric (PSAF) was synthesized via copolymerization of polysilicic acid (PSi), AlCl3 and FeCl3 for treating oily wastewater from Daqing gas field. This study investigated the effects of key preparation factors such as the degree of PSi's preactivation and the ratio of (Fe + Al)/Si and Al/Fe on both polymerization and coagulation performance exhibited by PSAF. To determine the optimal timing for introducing Al3+ and Fe3+, zeta potential, viscosity and particle size were investigated. Additionally, infrared spectroscopy, X-ray powder diffraction, polarizing microscopy and scanning electron microscope analysis were employed to investigate the structure and morphology of PSAF. The results indicate that under conditions characterized by a SiO2 mass fraction of 2.5% and pH = 4.5, an optimal timing for introducing Al3+ and Fe3+ is at 100 min when PSi exhibits moderate polymerization along with sufficient stability. When considering molar ratios such as (Al + Fe)/Si being 6:4 and Al/Fe being 5:5, respectively, PSAF falls within a "stable zone" enabling storage period up to 32 days. Moreover, Jar test results demonstrate that at a dosage of 200 mg/L PSAF for oily wastewater treatment in gas fields could reach the maximum turbidity removal efficiency up to 99.5% while oil removal efficiency reach 88.6% without pH adjustment. The copolymerization facilitates the formation of larger PSAF aggregates with positive potential, thereby augmenting the coagulants' adsorption bridging and charge neutralization capabilities. As a result, PSAF has great potential as a practical coagulant for treating oil-containing wastewater in industrial settings.


Assuntos
Águas Residuárias , Purificação da Água , Alumínio/química , Dióxido de Silício , Polímeros , Ferro/química , Purificação da Água/métodos , Compostos Férricos/química
8.
Int J Biol Macromol ; 262(Pt 1): 129837, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38302023

RESUMO

Starch/cellulose composite is one of the most promising systems since both matrix and reinforce agent have same chemical unite glucose, which results in an excellent compatibility. In this work, edible starch film was developed by compositing starch with diverse fibrillary celluloses (FCs) derived from okara, employing a confluence of chemical interactions and mechanical influences. Since diameter of the FCs can be easily controlled by processing methodologies, it is the first time to systematically investigate the effect of diameter of the FCs from macro to nano-scales on the performances of starch-based film. The fabricated macro- and nano-fibrillar celluloses and reinforced starch films were characterized by scanning electron microscope, optical microscopy, Fourier transform infrared spectroscopy, Rheometer and contact angle. Results showed that the FCs increased modulus (about 170 %) and tensile strength (about 180 %) significantly as expected since they are well-compatible and some chemical interactions. It was found that nano-fibrillary celluloses (CNFs) improve the toughness (about 20 %) of the starch film more efficiently, which improved the well-recognized weakness of starch-based materials. The nano-scale roughness on the surface of the starch film caused by different shrinkage ratios between starch and CNFs during drying reduced water sensitivity, which is another well-recognized weakness of starch film.


Assuntos
Filmes Comestíveis , Amido , Amido/química , Permeabilidade , Resistência à Tração , Celulose/química
9.
J Cardiothorac Surg ; 19(1): 101, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38374106

RESUMO

BACKGROUND: Acupuncture, a traditional Chinese medical treatment, has been gaining popularity over the years. However, it also presents certain risks. We report a case of a patient who discovered a foreign body in their lung several years after undergoing acupuncture. CASE PRESENTATION: A middle-aged woman presented to our hospital with chest pain. An X-ray revealed a needle-like foreign body in the middle lobe of her right lung. The patient had previously undergone acupuncture treatment for local pain in her lower back and lower extremities many years prior. Based on the imaging findings and her medical history, we hypothesized that the foreign body in her lung was a result of a dislodged acupuncture needle. Through preoperative 3-dimensional reconstruction and indocyanine green localization, we were able to locate the foreign body in the lateral segment of the right middle lobe. We successfully removed the foreign body via wedge resection, and the patient made a smooth recovery post-surgery. CONCLUSION: Acupuncturists and surgeons should remain vigilant about the potential risks associated with acupuncture.


Assuntos
Terapia por Acupuntura , Corpos Estranhos , Migração de Corpo Estranho , Humanos , Pessoa de Meia-Idade , Feminino , Agulhas/efeitos adversos , Terapia por Acupuntura/efeitos adversos , Corpos Estranhos/diagnóstico por imagem , Corpos Estranhos/etiologia , Corpos Estranhos/cirurgia , Radiografia , Dor no Peito , Migração de Corpo Estranho/diagnóstico por imagem , Migração de Corpo Estranho/etiologia
10.
Foods ; 13(4)2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38397494

RESUMO

Chinese steamed bread (CSB), which is widely consumed in East Asia, usually undergoes storage before consumption, but it is unclear how different storage temperatures affect CSB starch retrogradation and digestion properties, which are important for consumers. CSB was stored for 2 days at 25 °C, 4 °C, -18 °C, 4 °C/25 °C temperature cycling (i.e., 24 h at 4 °C, followed by 24 h at 25 °C) and -18 °C/ 25 °C temperature cycling. The results revealed for the first time that more orderly starch double helices are formed when CSB was stored at 4 °C or 4 °C/25 °C. Storage under -18 °C produced lower amounts of, but more heterogenous, starch double helices, with fewer B-type, but more V-type, crystallites. Compared to other storage temperatures, more long-range intermolecular interactions formed between the starch and protein at 4 °C or 4 °C/25 °C. CSB samples showed the slowest starch digestibility when stored at 4 °C. The impact of storage temperature on the starch retrogradation properties and digestibility of CSB also depended on the wheat variety, attributed to differences in the starch molecular structure. These results have significance and practical applications to help the CSB food industry to control starch retrogradation and digestibility. For example, CSB could be stored at 4 °C for 2 days in order to reduce its starch digestibility.

11.
Eur J Pediatr ; 183(4): 1901-1910, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38337095

RESUMO

The aim of the study was to determine the relationship between flatfoot morphology and body mass and height in children aged 6-12 years. A total of 6471 Chinese children (mean age 9.0 ± 1.9 years, 41% female) were assessed for foot morphometry, body height, and body mass index. Foot morphology, including foot length, width, girth, arch height, hallux valgus angle, and rearfoot valgus angle, was measured using a 3D laser scanner. Flatfoot evaluations were conducted using the Sztriter-Godunov index (KY) from footprints. All measurements were analyzed by age and sex using the mean values of the left and right sides. Comparisons were performed between flatfoot groups, between body mass index (BMI) groups, and between body height groups. The study revealed a significant decrease in the incidence of bipedal flatfoot with age (p < 0.001), whereas the prevalence of obesity remained consistent (p > 0.05). Bipedal flatfoot was associated with distinct morphological changes, including lower arches, reduced instep height, diminished ankle heights and a greater rearfoot valgus angle (p < 0.05). When comparing the BMI groups, overweight children had larger and thicker feet (p < 0.05), but no differences were found in arch height and ankle height (p > 0.05). When comparing the body height groups, short-statured children had a shorter feet girth, shorter arches, and shorter ankle height (p < 0.05), but no differences were found in the rearfoot valgus angle (p > 0.05). CONCLUSION: The main characteristics of flat feet include lower arches and instep heights and ankle heights but higher rearfoot valgus angles. In general, overweight children's feet do not have the common features of flat feet. In contrast, short children had similar features of flatfoot except for rearfoot valgus. Assessment of posture, such as rearfoot valgus, can be critical in identifying children with flat feet. WHAT IS KNOWN: • The morphology of children's feet is associated with body growth, but the relationship between flatfeet and body mass and height remains controversial. WHAT IS NEW: • Three-dimensional foot measurement shows that body mass is generally not associated with flatfeet, while short children have lower arches but no rearfoot valgus.


Assuntos
Pé Chato , Criança , Humanos , Feminino , Masculino , Pé Chato/epidemiologia , Pé Chato/complicações , Sobrepeso , Estatura , Pé/anatomia & histologia , Obesidade/complicações
12.
Food Chem ; 442: 138412, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38241996

RESUMO

This study aims to investigate how alkali lignin inhibits protein digestion and explore thermal treatment as a potential solution. Solid alkali lignin species pre-heated at different temperatures (150, 200, and 250 °C) and soluble acid-differentiated fractions are subjected to in vitro protein digestion. A range of techniques, including Thermogravimetric Analysis (TGA), Size-Exclusion Chromatography (SEC), Zeta Potential Analyzer, 1H NMR, Isothermal Titration Calorimetry (ITC), and Molecular Docking, were used to investigate the inhibitory mechanism of alkali lignin on pancreatic proteases hydrolysis. Our results suggest that soluble alkali lignin inhibits pancreatic trypsin and chymotrypsin, with the acid-differentiated soluble fraction (LgpH<1) displaying the strongest inhibition and proteases' binding affinity due to the abundance of polar groups (e.g., -OH, -CHO), which facilitate hydrogen-bond formation. Furthermore, pre-heating lignin (200 °C) was confirmed effective for removing LgpH<1 and its negative nutritional influence, providing a feasible strategy for overcoming the negative impact of alkali lignin on protein digestion.


Assuntos
Álcalis , Lignina , Lignina/metabolismo , Álcalis/química , Simulação de Acoplamento Molecular , Hidrólise , Ácidos , Quimotripsina
13.
World J Surg Oncol ; 22(1): 26, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38263144

RESUMO

OBJECTIVE: To explore the risk factors for disease progression after initial treatment of type B thymomas using a predictive nomogram model. METHODS: A single-center retrospective study of patients with type B thymoma was performed. The Cox proportional hazard model was used for univariate and multivariate analyses. Variables with statistical and clinical significance in the multivariate Cox regression were integrated into a nomogram to establish a predictive model for disease progression. RESULTS: A total of 353 cases with type B thymoma were retrieved between January 2012 and December 2021. The median follow-up was 58 months (range: 1-128 months). The 10-year progression-free survival (PFS) was 91.8%. The final nomogram model included R0 resection status and Masaoka stage, with a concordance index of 0.880. Non-R0 resection and advanced Masaoka stage were negative prognostic factors for disease progression (p < 0.001). No benefits of postoperative radiotherapy (PORT) were observed in patients with advanced stage and non-R0 resection (p = 0.114 and 0.284, respectively). CONCLUSION: The best treatment strategy for type B thymoma is the detection and achievement of R0 resection as early as possible. Long-term follow-up is necessary, especially for patients with advanced Masaoka stage and who have not achieved R0 resection. No prognostic benefits were observed for PORT.


Assuntos
Timoma , Neoplasias do Timo , Humanos , Nomogramas , Estudos Retrospectivos , Prognóstico , Progressão da Doença
14.
Carbohydr Polym ; 329: 121768, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38286543

RESUMO

In the current study, the effects of extrusion using a haake rheometer with a twin-roll mixer, with and without FA addition, on the structures and in vitro digestibility of starches from different sources were investigated. After extruding for 15 min at 90 °C with a moisture content of 40 %, no matter FA was added or not, lager Ap molecules were preferentially debranched, while Am with longer CL were depolymerized simultaneously, resulting to reduced averaged molecular size of Ap and shortened Am chains. Of all starches, regardless of their botanical backgrounds, although synergic effects were found between extrusion and FA addition on reducing their relative crystallinity and the ordered structures, distinctly different effects on the in vitro digestibility of these starches have also been observed especially regarding the digestion of starch branches with DP > 10 Particularly, the Am chains with DP 10-1000 was remaining undigested when FA was added. This study provides important information concerning how to adjust starch digestibility into a healthy range through altering the starch structures using extrusion technique with the addition of phytochemicals or not.


Assuntos
Ácidos Cumáricos , Amido , Amido/química , Digestão
15.
Nanoscale ; 16(5): 2391-2401, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38226664

RESUMO

Two-dimensional (2D) transition metal dichalcogenides (TMDCs) have been attracting much attention due to their rich physical and chemical properties. At the end of the chemical vapor deposition growth of 2D TMDCs, the adsorption of excess precursor clusters onto the sample is unavoidable, which will have significant effects on the properties of TMDCs. This is a concern to the academic community. However, the structures of the supported precursor clusters and their effects on the properties of the prepared 2D TMDCs are still poorly understood. Herein, taking monolayer WSe2 as the prototype, we investigated the structure and electronic properties of SeN, WN (N = 1-8), and W8-NSeN (N = 1-7) clusters adsorbed on monolayer WSe2 to gain atomic insight into the precursor cluster adsorption. In contrast to W clusters that tightly bind to the WSe2 surface, Se clusters except for Se1 and Se2 are weakly adsorbed onto WSe2. The interaction between W8-NSeN (N = 1-7) clusters and the WSe2 monolayer decreases with the increase in the Se/W ratio and eventually becomes van der Waals interaction for W1Se7. According to the phase diagram, increasing the Se/W ratio by changing the experimental conditions will increase the ratio of SeN and W1Se7 clusters in the precursor, which can be removed by proper annealing after growth. W clusters induce lots of defect energy levels in the band gap region, while the adsorption of W1Se7 and SeN clusters (N = 3-6, 8) promotes the spatial separation of photo generated carriers at the interface, which is important for optoelectronic applications. Our results indicate that by controlling the Se/W ratio, the interaction between the precursor clusters and WSe2 as well as the electronic properties of the prepared WSe2 monolayer can be effectively tuned, which is significant for the high-quality growth and applications of WSe2.

16.
Artigo em Inglês | MEDLINE | ID: mdl-38062753

RESUMO

To investigate the effects and underlying molecular mechanisms of the interaction between the non-structural protein 1 (NS1) and nucleolar and coiled-body phosphoprotein 1 (NOLC1) on rRNA synthesis through nucleolar telomeric repeat-binding factor 2 (TRF2) under nucleolar stress in avian influenza A virus infection. The analysis of TRF2 ties into the exploration of ribosomal protein L11 (RPL11) and mouse double minute 2 (MDM2) because TRF2 has been found to interact with NOLC1, and the RPL11-MDM2 pathway plays an important role in nucleolar regulation and cellular processes. Both human embryonic kidney 293T cells and human lung adenocarcinoma A549 cells were transfected with the plasmids pCAGGS-HA and pCAGGS-HA-NS1, respectively. In addition, A549 cells were transfected with the plasmids pEGFP-N1, pEGFP-N1-NS1, and pDsRed2-N1-TRF2. The cell cycle was detected by flow cytometry, and coimmunoprecipitation was applied to examine the interactions between different proteins. The effect of NS1 on TRF2 was detected by immunoprecipitation, and the colocalization of NOLC1 and TRF2 or NS1 and TRF2 was visualized by immunofluorescence. Quantitative real-time PCR was conducted to detect the expression of the TRF2 and p21. There is a strong interaction between NOLC1 and TRF2, and the colocalization of NOLC1 and TRF2 in the nucleus. The protein expression of NOLC1 in A549-HA-NS1 cells was lower than that in A549-HA cells, which was accompanied by the upregulated protein expression of p53 in A549-HA-NS1 cells (all p < .05). TRF2 was scattered throughout the nucleus without clear nucleolar aggregation. RPL11 specifically interacted with MDM2 in the NS1 group, and expression of the p21 gene was significantly increased in the HA-NS1 group compared with the HA group (p < .01). NS1 protein can lead to the reduced aggregation of TRF2 in the nucleolus, inhibition of rRNA expression, and cell cycle blockade by interfering with the NOLC1 protein and generating nucleolar stress.

18.
Int J Biol Macromol ; 258(Pt 2): 129040, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38154711

RESUMO

Although texture of cooked rice has been investigated with regard to its relation to starch structure, it remains unclear how starch molecular structure and water content together affect its texture. Thus, the texture, and starch molecular structure of 10 rice varieties and their leachates during cooking were studied with a range of rice-to-water ratios. Although hardness of cooked rice decreased, no trend for the alteration of stickiness observed over the increase of water content. Generally, more amylopectin with DP 12-36 and amylose with DP 5000-20,000 in leachate, less starch molecules with DP > 36 in residual materials resulted in a higher stickiness of cooked rice, which is rationalized by their slower retrogradation tendency and higher amount of non-reducing ends available for binding to textural probe. Rice-to-water ratio was another crucial factor in determining relations between starch structures and cooked rice texture. For example, more leached amylopectin with DP 12-100 resulted in a higher stickiness of cooked rice, while this was not the case for rice cooked at rice-to-water ratios of 1: 1.2 and 1: 1.4. These results give new insights on the effects of starch molecular structure and water content on the cooked rice texture.


Assuntos
Oryza , Amido , Amido/química , Amilopectina/química , Estrutura Molecular , Oryza/química , Amilose/química , Água , Culinária/métodos
19.
Phys Chem Chem Phys ; 25(48): 33152-33158, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38047897

RESUMO

Magnetic Fe3O4 nanoparticles show promising applications in nanomedicine. However, the saturation magnetization (MS) of Fe3O4 nanoparticles synthesized in laboratory is usually not high enough, which greatly limits their application in drug delivery and magnetic hyperthermia. Here, by accurate hybrid density functional computation, the doping behavior of group III elements (including Al, Ga, and In) and the effects on magnetic and electronic properties are well studied. The results show that the doping behavior depends on the concentration of dopants. Interestingly, appropriate Ga and In doping concentrations can significantly increase the MS of Fe3O4. In addition, the doping of group III elements (Al, Ga and In) into Fe3O4 would not induce any defect states in the band gap but slightly increases the band gap. Our results provide a simple and feasible scheme for increasing the MS of magnetite, which is significant for the applications of Fe3O4 nanoparticles in drug delivery and magnetic hyperthermia.

20.
Xenobiotica ; 53(12): 670-680, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37971898

RESUMO

Maintaining proper blood flow is critical to promoting good health. Nattokinase is a serine protease from Bacillus subtilis that has significant in vitro thrombolytic activity, but its mechanism as a dietary supplement to prevent thrombosis through intestinal absorption and transport is still unclear.The purpose of this study is to study the transport and internalisation mechanism of NK in the small intestine using animal models and Caco-2 cell monolayer models.This study first evaluated the preventive effect of supplementing low dose (4000 FU (Fibrin Unit)/kg, n = 6), medium dose (8000 FU/kg, n = 6), and high dose (12000 FU/kg, n = 6) of nattokinase on carrageenan induced thrombosis in mice. Subsequently, we used the rat gut sac model, ligated intestinal loop model, and Caco-2 cell uptake model to study the intestinal transport mechanism of NK.Results indicate that NK is a moderately absorbed biomolecule whose transport through enterocytes is energy- and time-dependent. Chlorpromazine, nystatin and EIPA all inhibited the endocytosis of NK to varying degrees, indicating that the endocytosis of NK in Caco-2 cells involves macropinocytosis, clathrin-mediated and caveolae-mediated pathway. These findings offer a theoretical basis for investigating the mechanism of oral NK supplementation in greater depth.


Assuntos
Intestino Delgado , Trombose , Humanos , Ratos , Camundongos , Animais , Células CACO-2 , Suplementos Nutricionais
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