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1.
Nucleic Acids Res ; 2024 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-39470718

RESUMO

The field of plant non-coding RNAs (ncRNAs) has seen significant advancements in recent years, with many ncRNAs recognized as important regulators of gene expression during plant development and stress responses. Moreover, the coding potential of these ncRNAs, giving rise to ncRNA-encoded peptides (ncPEPs), has emerged as an essential area of study. However, existing plant ncRNA databases lack comprehensive information on ncRNA-encoded peptides (ncPEPs) and cell type-specific interactions. To address this gap, we present ncPlantDB (https://bis.zju.edu.cn/ncPlantDB), a comprehensive database integrating ncRNA and ncPEP data across 43 plant species. ncPlantDB encompasses 353 140 ncRNAs, 3799 ncPEPs and 4 647 071 interactions, sourced from established databases and literature mining. The database offers unique features including translational potential data, cell-specific interaction networks derived from single-cell RNA sequencing and Ribo-seq analyses, and interactive visualization tools. ncPlantDB provides a user-friendly interface for exploring ncRNA expression patterns at the single-cell level, facilitating the discovery of tissue-specific ncRNAs and potential ncPEPs. By integrating diverse data types and offering advanced analytical tools, ncPlantDB serves as a valuable resource for researchers investigating plant ncRNA functions, interactions, and their potential coding capacity. This database significantly enhances our understanding of plant ncRNA biology and opens new avenues for exploring the complex regulatory networks in plant genomics.

2.
Plant Physiol ; 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39250762

RESUMO

Chromosome doubling-induced polyploidization is a popular tool for crop breeding. Polyploidy crops commonly have multiple advantages, including increased biomass and stress tolerance. However, little is known about the genes responsible for these advantages. We found kiwifruit (Actinidia chinensis cv. Hongyang) PECTIN METHYLESTERASE 2 (AcPME2)is substantially upregulated in artificially created tetraploid plants that show increased biomass and enhanced tolerance to osmotic stress. Overexpression (OE) of AcPME2 led to increased biomass and enhanced stress tolerance in Arabidopsis (Arabidopsis thaliana), tomato (Solanum lycopersicum), and kiwifruit. Upon short-term osmotic stress treatment, AcPME2-OE plants showed higher levels of demethylesterified pectins and more Ca2+ accumulation in the cell wall than Col-0 plants, which led to increased cell wall stiffness. The stress-induced plasmolysis assays indicated that AcPME2 dynamically mediated the cell wall stiffness in response to osmotic stress, which is dependent on Ca2+ accumulation. Transcriptomic analysis discovered that dozens of stress-responsive genes were significantly upregulated in the AcPME2-OE plants under osmotic stress. Besides, AcPME2-mediated cell wall reinforcement prevented cell wall collapse and deformation under osmotic stress. Our results revealed a single gene contributes to two advantages of polyploidization (increased biomass and osmotic stress tolerance) and that AcPME2 dynamically regulates cell wall stiffness in response to osmotic stress.

3.
J Neuroinflammation ; 21(1): 169, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38961424

RESUMO

BACKGROUND: Understanding the mechanism behind sepsis-associated encephalopathy (SAE) remains a formidable task. This study endeavors to shed light on the complex cellular and molecular alterations that occur in the brains of a mouse model with SAE, ultimately unraveling the underlying mechanisms of this condition. METHODS: We established a murine model using intraperitoneal injection of lipopolysaccharide (LPS) in wild type and Anxa1-/- mice and collected brain tissues for analysis at 0-hour, 12-hour, 24-hour, and 72-hour post-injection. Utilizing advanced techniques such as single-nucleus RNA sequencing (snRNA-seq) and Stereo-seq, we conducted a comprehensive characterization of the cellular responses and molecular patterns within the brain. RESULTS: Our study uncovered notable temporal differences in the response to LPS challenge between Anxa1-/- (annexin A1 knockout) and wild type mice, specifically at the 12-hour and 24-hour time points following injection. We observed a significant increase in the proportion of Astro-2 and Micro-2 cells in these mice. These cells exhibited a colocalization pattern with the vascular subtype Vas-1, forming a distinct region known as V1A2M2, where Astro-2 and Micro-2 cells surrounded Vas-1. Moreover, through further analysis, we discovered significant upregulation of ligands and receptors such as Timp1-Cd63, Timp1-Itgb1, Timp1-Lrp1, as well as Ccl2-Ackr1 and Cxcl2-Ackr1 within this region. In addition, we observed a notable increase in the expression of Cd14-Itgb1, Cd14-Tlr2, and Cd14-C3ar1 in regions enriched with Micro-2 cells. Additionally, Cxcl10-Sdc4 showed broad upregulation in brain regions containing both Micro-2 and Astro-2 cells. Notably, upon LPS challenge, there was an observed increase in Anxa1 expression in the mouse brain. Furthermore, our study revealed a noteworthy increase in mortality rates following Anxa1 knockdown. However, we did not observe substantial differences in the types, numbers, or distribution of other brain cells between Anxa1-/- and wildtype mice over time. Nevertheless, when comparing the 24-hour post LPS injection time point, we observed a significant decrease in the proportion and distribution of Micro-2 and Astro-2 cells in the vicinity of blood vessels in Anxa1-/- mice. Additionally, we noted reduced expression levels of several ligand-receptor pairs including Cd14-Tlr2, Cd14-C3ar1, Cd14-Itgb1, Cxcl10-Sdc4, Ccl2-Ackr1, and Cxcl2-Ackr1. CONCLUSIONS: By combining snRNA-seq and Stereo-seq techniques, our study successfully identified a distinctive cellular colocalization, referred to as a special pathological niche, comprising Astro-2, Micro-2, and Vas-1 cells. Furthermore, we observed an upregulation of ligand-receptor pairs within this niche. These findings suggest a potential association between this cellular arrangement and the underlying mechanisms contributing to SAE or the increased mortality observed in Anxa1 knockdown mice.


Assuntos
Astrócitos , Encéfalo , Modelos Animais de Doenças , Lipopolissacarídeos , Camundongos Knockout , Microglia , Encefalopatia Associada a Sepse , Animais , Camundongos , Lipopolissacarídeos/toxicidade , Encefalopatia Associada a Sepse/patologia , Encefalopatia Associada a Sepse/genética , Encefalopatia Associada a Sepse/metabolismo , Microglia/metabolismo , Microglia/patologia , Encéfalo/patologia , Encéfalo/metabolismo , Astrócitos/metabolismo , Astrócitos/patologia , Análise de Sequência de RNA/métodos , Camundongos Endogâmicos C57BL , Transcriptoma , Masculino
4.
Small ; 20(27): e2310908, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38279585

RESUMO

The high potassization/depotassization energy barriers and lack of efficient ion diffusion pathways are two serious obstacles for carbon-based materials to achieve satisfactory potassium ion storage performance. Herein, a facile and controllable one-step exfoliation-doping-etching strategy is proposed to construct heteroatoms (N, O, and S)-doped mesoporous few-layer carbon nanosheets (NOS-C). The mixed molten salts of KCl/K2SO4 are innovatively used as the exfoliators, dopants, and etching agents, which enable NOS-C with expanded interlayer spacing and uniformly distributed mesopores with the adjusted electronic structure of surrounding carbon atoms, contributing efficient dual (vertical and horizontal) K-ion diffusion pathways, low potassization/depotassization energy barriers and abundant active sites. Thus, the NOS anodes achieve a high reversible capacity of 516.8 mAh g-1 at 0.05 A g-1, superior rate capability of 202.8 mAh g-1 at 5 A g-1 and excellent long-term cyclic stability, and their practical application potential is demonstrated by the assembled potassium-ion full batteries. Moreover, a surface-interlayer synergetic K+ storage mechanism is revealed by a combined theoretical and experimental approach including in situ EIS, in situ Raman, ex situ XPS, and SEM analysis. The proposed K+ storage mechanism and unique structural engineering provide a new pathway for potassium-ion storage devices and even beyond.

5.
Eur Radiol ; 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38992109

RESUMO

OBJECTIVES: To establish and validate scoring models for predicting vessels encapsulating tumor clusters (VETC) in hepatocellular carcinoma (HCC) using computed tomography (CT) and magnetic resonance imaging (MRI), and to intra-individually compare the predictive performance between the two modalities. METHODS: We retrospectively included 324 patients with surgically confirmed HCC who underwent preoperative dynamic CT and MRI with extracellular contrast agent between June 2019 and August 2020. These patients were then divided into a discovery cohort (n = 227) and a validation cohort (n = 97). Imaging features and Liver Imaging Reporting and Data System (LI-RADS) categories of VETC-positive HCCs were evaluated. Logistic regression analyses were conducted on the discovery cohort to identify clinical and imaging predictors associated with VETC-positive cases. Subsequently, separate CT-based and MRI-based scoring models were developed, and their diagnostic performance was compared using generalized estimating equations. RESULTS: On both CT and MRI, VETC-positive HCCs exhibited a higher frequency of size > 5.0 cm, necrosis or severe ischemia, non-smooth tumor margin, targetoid appearance, intratumor artery, and heterogeneous enhancement with septations or irregular ring-like structure compared to VETC-negative HCCs (all p < 0.05). Regarding LI-RADS categories, VETC-positive HCCs were more frequently categorized as LR-M than VETC-negative cases (all p < 0.05). In the validation cohort, the CT-based model showed similar sensitivity (76.7% vs. 86.7%, p = 0.375), specificity (83.6% vs. 74.6%, p = 0.180), and area under the curve value (0.80 vs. 0.81, p = 0.910) to the MRI-based model in predicting VETC-positive HCCs. CONCLUSION: Preoperative CT and MRI demonstrated comparable performance in the identification of VETC-positive HCCs, thus displaying promising predictive capabilities. CLINICAL RELEVANCE STATEMENT: Both computed tomography and magnetic resonance imaging demonstrated promise in preoperatively identifying the vessel-encapsulating tumor cluster pattern in hepatocellular carcinoma, with no statistically significant difference between the two modalities, potentially adding additional prognostic value. KEY POINTS: Computed tomography (CT) and magnetic resonance imaging (MRI) show promise in the preoperative identification of vessels encapsulating tumor clusters-positive hepatocellular carcinoma (HCC). HCC with vessels encapsulating tumor cluster patterns were more frequently LR-M compared to those without. These CT and MRI models showed comparable ability in identifying vessels encapsulating tumor clusters-positive HCC.

6.
Nanotechnology ; 35(40)2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-38991504

RESUMO

Although the photoresponse cut-off wavelength of Si is about 1100 nm due to the Si bandgap energy, the internal photoemission effect (IPE) of the Au/Si junction in Schottky detector can extend the absorption wavelength, which makes it a promising candidate for the Si-based infrared detector. However, due to low light absorption, low photon-electron interaction, and poor electron injection efficiency, the near-infrared light detection efficiency of the Schottky detector is still insufficient. The synergistic effect of Si nano/microstructures with a strong light trapping effect and nanoscale Au films with surface plasmon enhanced absorption may provide an effective solution for improving the detection efficiency. In this paper, a large-area periodic Si microcone array covered by an Au film has successfully been fabricated by one-time dry etching based on the mature polystyrene microspheres lithography technique and vacuum thermal deposition, and its properties for hot electron-based near infrared photodetection are investigated. Optical measurements show that the 20 nm-thick Au covered Si microcone array exhibits a low reflectance and a strong absorption (about 85%) in wide wavelength range (900-2500 nm), and the detection responsivity can reach a value as high as 17.1 and 7.0 mA W-1at 1200 and 1310 nm under the front illumination, and 35.9 mA W-1at 1310 nm under the back illumination respectively. Three-dimensional finite difference time domain (3D-FDTD) simulation results show that the enhanced local electric field in the Au layer distributes near the air/Au interface under the front illumination and close to the Au/Si interface under the back illumination. The back illumination favors the injection of photo-generated hot electrons in Au layer into Si, which can explain the higher responsivity under the back illumination. Our research is expected to promote the practical application of Schottky photodetectors to Si-compatible near infrared photodetectors.

7.
Bioorg Med Chem ; 97: 117544, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-38071943

RESUMO

It's urgent to discover new antibiotics along with the increasing emergence and dissemination of multidrug resistant (MDR) bacterial pathogens. In the present investigation, morusin exhibited rapid bactericidal activity against methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE) by targeting the phospholipid of bacterial inner membrane, increasing membrane rigidity and disrupting bacterial homeostasis together with the membrane permeability, which caused fundamental metabolic disorders. Furthermore, morusin can also accumulate ROS, suppress H2S production, and aggravate oxidative damage in bacteria. Importantly, morusin also inhibited the spread of wounds and reduced the bacterial burden in the mouse model of skin infection caused by MRSA. It's a chance to meet the challenge of existing antibiotic resistance and avoid the development of bacterial resistance, given the multiple targets of morusin.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Morus , Animais , Camundongos , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana
8.
J Nat Prod ; 87(10): 2366-2375, 2024 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-39388644

RESUMO

Vancomycin-resistant Enterococcus (VRE) is an important nosocomial opportunistic pathogen that is associated with multidrug resistance. Here, we demonstrate that morellic acid inhibits VRE by restoring its sensitivity to vancomycin and ampicillin with low drug resistance and efficient biofilm clearance effects. Morellic acid binds to inner membrane phospholipids, such as phosphatidylethanolamine (PE), phosphatidylglycerol (PG), and cardiolipin (CL) of VRE, such that the fluidity and proton-motive force (PMF) interfere with the damaged inner membrane, causing intracellular reactive oxygen species (ROS) accumulation and bacterial death. Transcriptional analyses supported this effect on inner membrane-related pathways such as fatty acid biosynthesis and glycerophospholipid metabolism. Moreover, morellic acid significantly eliminated residual bacteria in the spleen, liver, kidneys, and abdominal effusion in mice. Our findings indicate the potential applications of morellic acid as an antibacterial agent or adjuvant for treating VRE infections.


Assuntos
Antibacterianos , Enterococos Resistentes à Vancomicina , Vancomicina , Xantonas , Enterococos Resistentes à Vancomicina/efeitos dos fármacos , Animais , Antibacterianos/farmacologia , Antibacterianos/química , Camundongos , Vancomicina/farmacologia , Xantonas/farmacologia , Xantonas/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Biofilmes/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Espécies Reativas de Oxigênio/metabolismo
9.
Qual Life Res ; 33(10): 2869-2880, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39046616

RESUMO

PURPOSE: The Functional Assessment of Cancer Therapy item (FACT-GP5) has the potential to provide an understanding of global treatment tolerability from the patient perspective. Longitudinal evaluations of the FACT-GP5 and challenges posed by data missing-not-at-random (MNAR) have not been explored. Robustness of the FACT-GP5 to missing data assumptions and the responsiveness of the FACT-GP5 to key side-effects are evaluated. METHODS: In a randomized, double-blind study (NCT00065325), postmenopausal women (n = 618) with hormone receptor-positive (HR+), advanced breast cancer received either fulvestrant or exemestane and completed FACT measures monthly for seven months. Cumulative link mixed models (CLMM) were fit to evaluate: (1) the trajectory of the FACT-GP5 and (2) the responsiveness of the FACT-GP5 to CTCAE grade, Eastern Cooperative Oncology Group (ECOG) Performance Status scale, and key side-effects from the FACT. Sensitivity analyses of the missing-at-random (MAR) assumption were conducted. RESULTS: Odds of reporting worse side-effect bother increased over time. There were positive within-person relationships between level of side-effect bother (FACT-GP5) and severity of other FACT items, as well as ECOG performance status and Common Terminology Criteria for Adverse Events (CTCAE) grade. The number of missing FACT-GP5 assessments impacted the trajectory of the FACT-GP5 but did not impact the relationships between the FACT-GP5 and other items (except for nausea [FACT-GP2]). CONCLUSIONS: Results support the responsiveness of the FACT-GP5. Generally speaking, the responsiveness of the FACT-GP5 is robust to missing assessments. Missingness should be considered, however, when evaluating change over time of the FACT-GP5. TRIAL REGISTRATION: NCT00065325. TRIAL REGISTRATION YEAR: 2003.


Researchers have been exploring the use of a single question, FACT-GP5 ("I am bothered by side effects of treatment"), as a quick way to learn about drug tolerability from the patients' perspective. This study explores if this single question can capture changes in tolerability during treatment, and if the assessment is missed by patients, whether that impacts the interpretation of tolerability. In our study, we found that the FACT-GP5 can be used to understand how tolerability changes during treatment. Missing assessments of the FACT-GP5 are important to account for when interpreting results. The FACT-GP5 may be a useful question for capturing the patient experience of drug tolerability.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Método Duplo-Cego , Neoplasias da Mama/tratamento farmacológico , Pessoa de Meia-Idade , Idoso , Androstadienos/uso terapêutico , Androstadienos/administração & dosagem , Fulvestranto/uso terapêutico , Fulvestranto/administração & dosagem , Qualidade de Vida , Inquéritos e Questionários , Pós-Menopausa
10.
BMC Public Health ; 24(1): 365, 2024 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-38310254

RESUMO

BACKGROUND: Anxiety and depression can influence adherence to Pre-exposure Prophylaxis (PrEP). However, there is limited research on the temporal dynamics of anxiety and depression among men who have sex with men (MSM) using PrEP. METHODS: From December 2018 to November 2020, we administered the Hospital Anxiety and Depression Scale (HADS) to participants in the China Real-World Oral Intake of PrEP (CROPrEP) to measure their anxiety and depression levels. The group-based trajectory model (GBTM) depicted the dynamic changes of anxiety and depression scores over time. RESULTS: A total of 1023 MSM were included, with 4523 follow-up assessments. The GBTM categorized the trajectories into three distinct patterns: consistently low (54.8% for anxiety, 60.7% for depression), consistently moderate (39.3% for anxiety, 31.4% for depression), and high but bell-shaped (5.9% for anxiety, 7.9% for depression). Higher anxiety levels were associated with being aged 18-30 years old, earning less than US$619 per month, female-identifying, adopting the bottom sexual role with men, and having two or more anal sex partners in the past three months; similarly, higher depression levels correlated with a monthly income under US$619, female-identifying, sexual behavior as bottom and a positive syphilis at baseline. PrEP adherence was notably lower in the high but bell-shaped anxiety and depression group compared to the other groups, particularly at the 12th-month follow-up. CONCLUSIONS: Close monitoring of anxiety and depression levels in MSM on PrEP is crucial. Provision of targeted mental health support is essential to enhance PrEP effectiveness.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Profilaxia Pré-Exposição , Minorias Sexuais e de Gênero , Masculino , Humanos , Feminino , Adolescente , Adulto Jovem , Adulto , Homossexualidade Masculina , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Infecções por HIV/tratamento farmacológico , Tenofovir/uso terapêutico , Depressão/epidemiologia , Fármacos Anti-HIV/uso terapêutico , Adesão à Medicação , Comportamento Sexual , Ansiedade/epidemiologia , China/epidemiologia
11.
Biomed Chromatogr ; 38(3): e5802, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38110194

RESUMO

Bicuculline is a natural isoquinoline alkaloid that works as a gamma-aminobutyric acid receptor antagonist. It is widely found in Papaveraceae plants used in traditional Chinese medicines. Bicuculline not only has been shown to have favorable analgesic, memory-improving, and anxiolytic effects but may also cause adverse effects such as convulsions and epilepsy. A simple, rapid, and sensitive method was developed and validated for the determination of bicuculline in the plasma and tissue samples in rats by ultra-high-performance liquid chromatography-tandem mass spectrometry (MS/MS). The chromatographic separation was performed on a Thermo Scientific C18 column. The MS/MS system was operated in the positive multiple reaction monitoring mode, and the precursor-product ion transitions were optimized as m/z 368.0 → 307.1 for bicuculline and as 354.1 → 188.1 for protopine (internal standard). The linearity, accuracy, precision, recovery, and matrix effect were within acceptable limits. The experimental data showed that bicuculline was rapidly absorbed and eliminated in rats, with a moderate plasma protein binding ratio and low bioavailability. The main tissues of distribution were the kidney, liver, and brain; bicuculline could exert its pharmacological effects across the blood-brain barrier. This study has positive implications for the clinical use of herbal medicines containing bicuculline and for further development.


Assuntos
Espectrometria de Massas em Tandem , Ratos , Animais , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Bicuculina , Ratos Sprague-Dawley , Distribuição Tecidual , Ligação Proteica , Administração Intravenosa , Reprodutibilidade dos Testes
12.
J Med Internet Res ; 26: e58591, 2024 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-39471367

RESUMO

BACKGROUND: To date, no randomized controlled trials have specifically addressed behavior changes after HIV self-testing (HIVST) among transgender women. OBJECTIVE: This study aims to evaluate the effects of HIVST on changes in HIV testing behavior, frequency of condomless sex, and partner numbers among transgender women in China. METHODS: Participants were recruited from 2 Chinese cities using both online and offline methods. Transgender women were randomly assigned to receive an HIVST intervention. Data from the previous 3 months were collected at baseline, 3 months, and 6 months. The primary outcome was the mean change in the number of HIV tests among transgender women during the 6-month follow-up. An intention-to-treat analysis was conducted. The statistical analysis used analysis of covariance and linear mixed-effects models. RESULTS: From February to June 2021, and 255 transgender women were recruited, of which only 36.5% (93/255) had a steady job, and 27.1% (69/255) earned less than US $414.9 of income per month. They were randomly assigned to the intervention (n=127) and control (n=128) groups. At 6 months, the mean number of HIV tests was 2.14 (95% CI 1.80-2.48) in the intervention group and 1.19 (95% CI 0.99-1.40) in the control group (P<.001), with increases of 0.84 (95% CI 0.54-1.14) and 0.11 (95% CI -0.19-0.41) over 6 months, respectively. The net increase was 0.73 (95% CI 0.31-1.15; P<.001), with a similar adjusted result. No significant differences in the frequency of condomless sex or partner numbers were observed between the 2 groups. CONCLUSIONS: HIVST is an effective strategy for enhancing regular HIV testing behavior among transgender women in China. This strategy should be combined with measures to address the financial vulnerability of the transgender women community to reduce subsequent risk behaviors, including condomless sex. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR2000039766; https://www.chictr.org.cn/showproj.html?proj=61402.


Assuntos
Infecções por HIV , Autoteste , Pessoas Transgênero , Humanos , Pessoas Transgênero/psicologia , Pessoas Transgênero/estatística & dados numéricos , Feminino , China , Adulto , Infecções por HIV/diagnóstico , Infecções por HIV/prevenção & controle , Infecções por HIV/psicologia , Masculino , Comportamento de Redução do Risco , Adulto Jovem , Teste de HIV/métodos , Teste de HIV/estatística & dados numéricos
13.
Chem Biodivers ; 21(7): e202400634, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38726746

RESUMO

Molybdenum disulfide nanoflowers (MoS2 NFs) were prepared by hydrothermal method. The prepared MoS2 NFs was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), specific surface areas, Raman and X-ray photoelectron spectroscopy (XPS). The characterization results show that the flower-like spherical MoS2 is composed of many ultra-thin nanosheets with an average diameter of about 300-400 nm. MoS2 NFs also exhibits excellent UV-vis absorption and high fluorescence intensity. In order to explore the biological behavior of MoS2 NFs, the interaction between MoS2 NFs and bovine serum albumin (BSA) was studied by UV-Vis absorption, fluorescence, synchronous fluorescence spectra, and cyclic voltammetry. The results of absorption and fluorescence show that MoS2 NFs and BSA interact strongly through the formation of complexes in the ground state, and the static quenching is the main mechanism. The Stern-Volmer constant and the quenching constant was calculated about 3.79×107 L mol-1 and 3.79×1015 L mol-1 s-1, respectively. The synchronous fluorescence implied that MoS2 in the complex may mainly bind to tryptophan residues of BSA. The cyclic voltammograms indicated that the addition of BSA makes electron reduction of MoS2 NFs more difficult than the corresponding free state. The results show that hydrophobic forces play a major role in the binding interaction between BSA and MoS2 NFs.


Assuntos
Dissulfetos , Molibdênio , Nanoestruturas , Soroalbumina Bovina , Espectrometria de Fluorescência , Soroalbumina Bovina/química , Soroalbumina Bovina/metabolismo , Molibdênio/química , Dissulfetos/química , Animais , Bovinos , Nanoestruturas/química , Espectrofotometria Ultravioleta , Tamanho da Partícula , Espectroscopia Fotoeletrônica , Propriedades de Superfície
14.
Molecules ; 29(18)2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39339282

RESUMO

Three-dimensional plasma nanostructures with high light-thermal conversion efficiency show the prospect of industrialization in various fields and have become a research hotspot in areas of light-heat utilization, solar energy capture, and so on. In this paper, a simple chemical synthesis method is proposed to prepare gold nanoparticles, and the electrophoretic deposition method is used to assemble large-area three-dimensional gold nanostructures (3D-GNSs). The light-thermal water evaporation monitoring and surface-enhanced Raman scattering (SERS) measurements of 3D-GNSs were performed via theoretical simulation and experiments. We reveal the physical processes of local electric field optical enhancement and the light-thermal conversion of 3D-GNSs. The results show that with the help of the efficient optical trapping and super-hydrophilic surface properties of 3D-GNSs, they have a significant effect in accelerating water evaporation, which was increased by nearly eight times. At the same time, the three-dimensional SERS substrates based on gold nanosphere particles (GNSPs) and gold nanostar particles (GNSTs) had limited sensitivities of 10-10 M and 10-12 M to R6G molecules, respectively. Therefore, 3D-GNSs show strong competitiveness in the fields of solar-energy-induced water purification and the Raman trace detection of organic molecules.

15.
Molecules ; 29(19)2024 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-39407562

RESUMO

Three novel ent-kaurane diterpenes, namely sigesbeckin A-C (1-3), in conjunction with eight previously identified analogues (4-11), were isolated from Sigesbeckia orientalis. Their chemical structures were resolved through multiple spectroscopic analyses. All compounds were assessed for antimicrobial bioactivity against methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE) strains. In particular, compounds 1 and 5 demonstrated moderate efficacy, with MIC values of 64 µg/mL. Moreover, compounds 3, 5, and 11 were found to synergize with doxorubicin hydrochloride (DOX) and vancomycin (VAN) against MRSA and VRE. The aforementioned findings offer valuable insights for the development of novel alternatives to antibiotics, which can effectively tackle the escalating issue of antibiotic resistance.


Assuntos
Antibacterianos , Diterpenos do Tipo Caurano , Staphylococcus aureus Resistente à Meticilina , Testes de Sensibilidade Microbiana , Diterpenos do Tipo Caurano/farmacologia , Diterpenos do Tipo Caurano/química , Diterpenos do Tipo Caurano/isolamento & purificação , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Asteraceae/química , Enterococos Resistentes à Vancomicina/efeitos dos fármacos , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Vancomicina/farmacologia , Vancomicina/química , Doxorrubicina/farmacologia , Sinergismo Farmacológico , Sigesbeckia
16.
Virol J ; 20(1): 38, 2023 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-36849974

RESUMO

BACKGROUND: As a result of antigenic drift, current influenza vaccines provide limited protection against circulating influenza viruses, and vaccines with broad cross protection are urgently needed. Hemagglutinin stalk domain and ectodomain of matrix protein 2 are highly conserved among influenza viruses and have great potential for use as a universal vaccine. METHODS: In this study, we co-expressed the stalk domain and M2e on the surface of cell membranes and generated chimeric and standard virus-like particles of influenza to improve antigen immunogenicity. We subsequently immunized BALB/c mice through intranasal and intramuscular routes. RESULTS: Data obtained demonstrated that vaccination with VLPs elicited high levels of serum-specific IgG (approximately 30-fold higher than that obtained with soluble protein), induced increased ADCC activity to the influenza virus, and enhanced T cell as well as mucosal immune responses. Furthermore, mice immunized by VLP had elevated level of mucosal HA and 4M2e specific IgA titers and cytokine production as compared to mice immunized with soluble protein. Additionally, the VLP-immunized group exhibited long-lasting humoral antibody responses and effectively reduced lung viral titers after the challenge. Compared to the 4M2e-VLP and mHA-VLP groups, the chimeric VLP group experienced cross-protection against the lethal challenge with homologous and heterologous viruses. The stalk domain specific antibody conferred better protection than the 4M2e specific antibody. CONCLUSION: Our findings demonstrated that the chimeric VLPs anchored with the stalk domain and M2e showed efficacy in reducing viral loads after the influenza virus challenge in the mice model. This antibody can be used in humans to broadly protect against a variety of influenza virus subtypes. The chimeric VLPs represent a novel approach to increase antigen immunogenicity and are promising candidates for a universal influenza vaccine.


Assuntos
Vacinas contra Influenza , Influenza Humana , Vacinas de Partículas Semelhantes a Vírus , Animais , Humanos , Camundongos , Deriva e Deslocamento Antigênicos , Membrana Celular , Camundongos Endogâmicos BALB C , Vacinas de Partículas Semelhantes a Vírus/metabolismo , Vacinas de Partículas Semelhantes a Vírus/farmacologia
17.
Eur Radiol ; 33(8): 5801-5811, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36894754

RESUMO

OBJECTIVES: To evaluate the value of using enhancing capsule (EC) or modified capsule appearance as a major feature in LI-RADS for diagnosing HCC ≤ 3.0 cm on gadoxetate disodium-enhanced MRI (Gd-EOB-MRI), and to explore the relationship between the imaging features and the histological fibrous capsule. METHODS: This retrospective study enrolled 342 hepatic lesions ≤ 3.0 cm in 319 patients that underwent Gd-EOB-MRIs from January 2018 to March 2021. During dynamic phases and hepatobiliary phase, the modified capsule appearance added the nonenhancing capsule (NEC) (modified LI-RADS + NEC) or corona enhancement (CoE) (modified LI-RADS + CoE) to EC as an alternative capsule appearance. Inter-reader agreement of imaging features was assessed. The diagnostic performances of LI-RADS, LI-RADS with EC ignored, and two modified LI-RADS were compared, followed by Bonferroni correction. Multivariable regression analysis was performed to identify the independent features associated with the histological fibrous capsule. RESULTS: The inter-reader agreement on EC (0.64) was lower than that on the NEC alternative (0.71) but better than that on CoE alternative (0.58). For HCC diagnosis, compared to LI-RADS, LI-RADS with EC ignored showed significantly lower sensitivity (72.7% vs. 67.4%, p < 0.001) with comparable specificity (89.3% vs. 90.7%, p = 1.000). Two modified LI-RADS showed slightly higher sensitivity and lower specificity than LI-RADS, without statistical significance (all p ≥ 0.006). The AUC was highest with modified LI-RADS + NEC (0.82). Both EC and NEC were significantly associated with the fibrous capsule (p < 0.05). CONCLUSION: EC appearance improved the diagnostic sensitivity of LI-RADS for HCC ≤ 3.0 cm on Gd-EOB-MRI. Considering NEC as an alternative capsule appearance allowed for better inter-reader reliability and comparable diagnostic ability. KEY POINTS: • Using the enhancing capsule as a major feature in LI-RADS significantly improved the sensitivity of diagnosing HCC ≤ 3.0 cm without reducing specificity on gadoxetate disodium-enhanced MRI. • Compared to the corona enhancement, the nonenhancing capsule might be a preferable alternative capsule appearance for diagnosing HCC ≤ 3.0 cm. • Capsule appearance should be considered a major feature in LI-RADS for diagnosing HCC ≤ 3.0 cm, regardless whether the capsule appears to be enhancing or nonenhancing.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Meios de Contraste/farmacologia , Estudos Retrospectivos , Reprodutibilidade dos Testes , Gadolínio DTPA , Imageamento por Ressonância Magnética/métodos , Sensibilidade e Especificidade
18.
Macromol Rapid Commun ; 44(17): e2300176, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37071857

RESUMO

The kinetic paths of structural evolution and formation of block copolymer (BCP) particles are explored using dynamic self-consistent field theory (DSCFT). It is shown that the process-directed self-assembly of BCP immersed in a poor solvent leads to the formation of striped ellipsoids, onion-like particles and double-spiral lamellar particles. The theory predicts a reversible path of shape transition between onion-like particles and striped ellipsoidal ones by regulating the temperature (related to the Flory-Huggins parameter between the two components of BCP, χAB ) and the selectivity of solvent toward one of the two BCP components. Furthermore, a kinetic path of shape transition from onion-like particles to double-spiral lamellar particles, and then back to onion-like particles is demonstrated. By investigating the inner-structural evolution of a BCP particle, it is identified that changing the intermediate bi-continuous structure into a layered one is crucial for the formation of striped ellipsoidal particles. Another interesting finding is that the formation of onion-like particles is characterized by a two-stage microphase separation. The first is induced by the solvent preference, and the second is controlled by the thermodynamics. The findings lead to an effective way of tailoring nanostructure of BCP particles for various industrial applications.


Assuntos
Nanoestruturas , Poliestirenos , Poliestirenos/química , Polímeros/química , Temperatura , Nanoestruturas/química , Solventes/química
19.
J Sep Sci ; 46(17): e2200843, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37349854

RESUMO

Monoterpene indole alkaloids exhibit structural diversity in herbal resources and have been developed as promising drugs owing to their significant biological activities. Confidential identification and quantification of monoterpene indole alkaloids is the key to quality control of target plants in industrial production but has rarely been reported. In this study, quantitative performance of three data acquisition modes of ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry including full scan, auto-MS2 and target-MS2 , was evaluated and compared for specificity, sensitivity, linearity, precision, accuracy, and matrix effect using five monoterpene indole alkaloids (scholaricine, 19-epi-scholaricine, vallesamine, picrinine, and picralinal). Method validations indicated that target-MS2 mode showed predominant performance for simultaneous annotation and quantification of analytes, and was then applied to determine monoterpene indole alkaloids in Alstonia scholaris (leaves, barks) after extraction procedures optimization using Box-Behnken design of response surface methodology. The variations of A. scholaris monoterpene indole alkaloids in different plant parts, harvest periods, and post-handling processes, were subsequently investigated. The results indicated that target-MS2 mode could improve the quantitative capability of ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry for structure-complex monoterpene indole alkaloids in herbal matrices. Alstonia scholaris, monoterpene indole alkaloids, quadrupole time of flight mass spectrometry, qualitative and quantitative analysis, ultra-high-performance liquid chromatography.


Assuntos
Alstonia , Alcaloides de Triptamina e Secologanina , Cromatografia Líquida de Alta Pressão , Alstonia/química , Alcaloides Indólicos/química , Espectrometria de Massas/métodos , Monoterpenos
20.
Ecotoxicol Environ Saf ; 259: 115027, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37207578

RESUMO

Our previous study showed 1-Nitropyrene (1-NP) exposure disrupted testicular testosterone synthesis in mouse, but the exact mechanism needs further investigation. The present research found 4-phenylbutyric acid (4-PBA), an endoplasmic reticulum (ER) stress inhibitor, recovered 1-NP-induced ER stress and testosterone synthases reduction in TM3 cells. GSK2606414, a protein kinase-like ER kinase (PERK) kinase inhibitor, attenuated 1-NP-induced PERK-eukaryotic translation initiation factor 2α (eIF2α) signaling activation and downregulation of steroidogenic proteins in TM3 cells. Both 4-PBA and GSK2606414 attenuated 1-NP-induced steroidogenesis disruption in TM3 cells. Further studies used N-Acetyl-L-cysteine (NAC) as a classical antioxidant to explore whether oxidative stress-activated ER stress mediated 1-NP-induced testosterone synthases reduction and steroidogenesis disruption in TM3 cells and mouse testes. The results showed NAC pretreatment mitigated oxidative stress, and subsequently attenuated ER stress, particularly PERK-eIF2α signaling activation, and downregulation of testosterone synthases in 1-NP-treated TM3 cells. More importantly, NAC extenuated 1-NP-induced testosterone synthesis in vitro and in vivo. The current work indicated that oxidative stress-caused ER stress, particularly PERK-eIF2α pathway activation, mediates 1-NP-downregulated steroidogenic proteins and steroidogenesis disruption in TM3 cells and mouse testes. Significantly, the current study provides a theoretical basis and demonstrates the experimental evidence for the potential application of antioxidant, such as NAC, in public health prevention, particularly in 1-NP-induced endocrine disorder.


Assuntos
Antioxidantes , Testículo , Masculino , Camundongos , Animais , Testículo/metabolismo , Antioxidantes/metabolismo , Fator de Iniciação 2 em Eucariotos/metabolismo , Estresse do Retículo Endoplasmático/fisiologia , Testosterona/metabolismo , Estresse Oxidativo , Acetilcisteína/farmacologia , Acetilcisteína/metabolismo
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