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1.
Materials (Basel) ; 17(11)2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38893758

RESUMO

Negative thermal expansion (NTE) ceramics Sm0.85Zn0.15MnO3 (SZMO) and ZrMgMo3O12 (ZMMO) were selected to prepare Sm0.85Zn0.15MnO3-ZrMgMo3O12/Al-20Si (SZMO-ZMMO/Al-20Si) composites using ball milling and vacuum heating-press sintering processes in this study. The synergistic effect of the SZMO and ZMMO NTE ceramic reinforcements on the microstructure, mechanical properties, and coefficient of thermal expansion (CTE) of the composites was investigated. The results show that the processes of ball milling and sintering did not induce the decomposition of SZMO or ZMMO NTE ceramic reinforcements, nor did they promote a reaction between the Al-20Si matrix and SZMO or ZMMO NTE ceramic reinforcements. However, the excessive addition of SZMO and ZMMO NTE ceramics led to their aggregation within the composite. Adding a small amount of SZMO in combination with ZMMO effectively increased hardness and yield strength while reducing CTE in the Al-20Si alloy. The improvement in strength was primarily provided by SZMO, while the inhibition effect on CTE was primarily provided by ZMMO. An evaluation parameter denoted as α was proposed to evaluate the synergy effects of SZMO and ZMMO NTE ceramic reinforcements on the mechanical properties and CTE of the composites. Based on this parameter, among all composites fabricated, adding 2.5 vol% SZMO NTE ceramic and 10 vol% ZMMO NTE ceramic resulted in an optimal balance between CTE and strength for these composites with a compressive yield strength of 349.72 MPa and a CTE of 12.55 × 10-6/K, representing a significant increase in yield strength by 79.20% compared to that of Al-20Si alloy along with a notable reduction in CTE by 26.44%.

2.
Food Chem ; 456: 140064, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38878548

RESUMO

Cysteine (Cys) not only plays an indispensable role in maintaining the redox balance in organisms, but is also an important nutrient in the food industry. Fluorescence-based detection systems have emerged as an effective method to track the locations and concentrations of different species. To achieve efficient monitoring of Cys in both food samples and biological systems, a novel lipid droplet (LD) targeted fluorescent probe (namely NIT-Cys) was constructed for the turn-on detection of Cys, characterized by a large Stokes shift (142 nm), a short response time (<8 min), and a low Cys detection limit (39 nM). Furthermore, the NIT-Cys probe has been successfully used not only to quantify the amounts of Cys in selected food samples, but also to enable the visualization of endogenous Cys in acetaminophen (APAP)-induced drug-induced liver injury cells, zebrafish larvae and mice models. Consequently, the work presented here provides an efficient tool for monitoring Cys.

3.
World Neurosurg ; 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38871284

RESUMO

BACKGROUND: The fusion rate, clinical efficacy, and complications of minimally invasive fusion surgery and open fusion surgery in the treatment of lumbar degenerative disease are still unclear. METHODS: We conducted a literature search using PubMed, Embase, Cochrane Library, CNKI, and WANFANG databases. RESULTS: This study included 38 retrospective studies involving 3,097 patients. Five intervention modalities were considered: unilateral biportal endoscopic-lumbar interbody fusion (UBE-LIF), percutaneous endoscopic-lumbar interbody fusion (PE-LIF), minimally invasive-transforaminal lumbar interbody fusion (MIS-TLIF), transforaminal lumbar interbody fusion (TLIF), and posterior lumbar interbody fusion (PLIF). Quality assessment indicated that each study met acceptable quality standards. PE-LIF demonstrated reduced low back pain (OR=0.50, CI: 0.38-0.65) and lower complication rate (OR=0.46, CI: 0.25-0.87) compared to PLIF. However, in indirect comparisons, PE-LIF showed the lowest fusion rates, with the ranking as follows: UBE-LIF (83.2%) > MIS-TLIF (59.6%) > TLIF (44.3%) > PLIF (39.8%) > PE-LIF (23.1%). With respect to low back pain relief, PE-LIF yielded the best results, with the order of relief as follows: PE-LIF (96.4%) > MIS-TLIF (64.8%) > UBE-LIF (62.6%) > TLIF (23.0%) > PLIF (3.2%). Global and local consistency tests showed satisfactory results, and heterogeneity tests indicated good stability. CONCLUSIONS: Compared to conventional open surgery, minimally invasive fusion surgery offered better scores for low back pain and Oswestry Disability Index, lower complication rates, reduced bleeding, and shorter hospital stays. However, minimally invasive fusion surgery did not show a significant advantage in terms of fusion rate and had a longer operative time.

4.
Appl Radiat Isot ; 210: 111367, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38805984

RESUMO

In this paper, a comprehensive hybrid K-edge/XRF densitometer (HKED) device model is constructed using MCNP simulation. After the modeling process, a systematic simulation study is conducted to analyze the physical parameters and material selection of KED and XRF. The simulation results reveal that the optimal parameters for the X-ray tube are an X-ray source voltage of 160 kV and a 1 mm Fe filter. The sample should be placed in a vial with an inner diameter of 1.4 cm and an outer diameter of 2 cm. For the KED technique, the determined main parameters are a 1.9 cm Fe filter rod and an inner diameter of 0.08 cm for the collimator. For the XRF technique, the determined main parameters are a 0.01 cm Gd filter and an inner diameter of 0.3 cm for the collimator, with a detector angle of 150°. After selecting appropriate parameters, the average calibration factor Δµ of the KED technique was found to be 3.301 cm2 g-1, with a relative standard deviation (RSD) of 3.36%. Additionally, the comparison between the simulated and calculated values of uranium concentration revealed a minimum measurement error of 0.4%. The minimum detection concentration of KED for uranium solutions is approximately 1 g/L. For plutonium solutions ranging from 0.5 to 20 g/L, linear fitting of the Ka1 net peak area and plutonium concentration showed a coefficient of determination (R2) of 0.999. The detection limit of XRF for plutonium measurement was 2.33✕10-4 g/L. The linear fitting coefficients (R2) of uranium concentration versus K-edge transmission rate and plutonium concentration versus Ka1 net peak area for the hybrid technique in measuring uranium-plutonium mixed solutions are determined as 0.999 and 0.996, respectively, demonstrating the response relationship of the HKED device to uranium and plutonium under different concentrations.

5.
Int J Biol Macromol ; 269(Pt 1): 131990, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38704067

RESUMO

Animal-derived venom, like snake venom, has been proven to be valuable natural resources for the drug development. Previously, snake venom was mainly investigated in its pharmacological activities in regulating coagulation, vasodilation, and cardiovascular function, and several marketed cardiovascular drugs were successfully developed from snake venom. In recent years, snake venom fractions have been demonstrated with anticancer properties of inducing apoptotic and autophagic cell death, restraining proliferation, suppressing angiogenesis, inhibiting cell adhesion and migration, improving immunity, and so on. A number of active anticancer enzymes and peptides have been identified from snake venom toxins, such as L-amino acid oxidases (LAAOs), phospholipase A2 (PLA2), metalloproteinases (MPs), three-finger toxins (3FTxs), serine proteinases (SPs), disintegrins, C-type lectin-like proteins (CTLPs), cell-penetrating peptides, cysteine-rich secretory proteins (CRISPs). In this review, we focus on summarizing these snake venom-derived anticancer components on their anticancer activities and underlying mechanisms. We will also discuss their potential to be developed as anticancer drugs in the future.


Assuntos
Antineoplásicos , Venenos de Serpentes , Humanos , Venenos de Serpentes/química , Antineoplásicos/farmacologia , Antineoplásicos/química , Animais , Neoplasias/tratamento farmacológico , L-Aminoácido Oxidase/química , L-Aminoácido Oxidase/farmacologia , Apoptose/efeitos dos fármacos , Fosfolipases A2/metabolismo , Fosfolipases A2/química , Toxinas Biológicas/química , Toxinas Biológicas/farmacologia
6.
Front Optoelectron ; 17(1): 14, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38802674

RESUMO

In this paper, we report a coherent beam combining (CBC) system that involves two thulium-doped all-polarization maintaining (PM) fiber chirped pulse amplifiers. Through phase-locking the two channels via a fiber stretcher by using the stochastic parallel gradient descent (SPGD) algorithm, a maximum average power of 265 W is obtained, with a CBC efficiency of 81% and a residual phase error of λ/17. After de-chirping by a pair of diffraction gratings, the duration of the combined laser pulse is compressed to 690 fs. Taking into account the compression efficiency of 90% and the main peak energy proportion of 91%, the corresponding peak power is calculated to be 4 MW. The laser noise characteristics before and after CBC are examined, and the results indicate that the CBC would degrade the low frequency relative intensity noise (RIN), of which the integration is 1.74% in [100 Hz, 2 MHz] at the maximum combined output power. In addition, the effects of the nonlinear spectrum broadening during chirped pulse amplification on the CBC efficiency are also investigated, showing that a higher extent of pulse stretching is effective in alleviating the spectrum broadening and realizing a higher output power with decent combining efficiency.

7.
Ecotoxicol Environ Saf ; 276: 116296, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38593498

RESUMO

Microplastics (MPs), which are prevalent and increasingly accumulating in aquatic environments. Other pollutants coexist with MPs in the water, such as pesticides, and may be carried or transferred to aquatic organisms, posing unpredictable ecological risks. This study sought to assess the adsorption of lambda-cyhalothrin (LCT) by virgin and aged polyethylene MPs (VPE and APE, respectively), and to examine their influence on LCT's toxicity in zebrafish, specifically regarding acute toxicity, oxidative stress, gut microbiota and immunity. The adsorption results showed that VPE and APE could adsorb LCT, with adsorption capacities of 34.4 mg∙g-1 and 39.0 mg∙g-1, respectively. Compared with LCT exposure alone, VPE and APE increased the acute toxicity of LCT to zebrafish. Additionally, exposure to LCT and PE-MPs alone can induce oxidative stress in the zebrafish gut, while combined exposure can exacerbate the oxidative stress response and intensify intestinal lipid peroxidation. Moreover, exposure to LCT or PE-MPs alone promotes inflammation, and combined exposure leads to downregulation of the myd88-nf-κb related gene expression, thus impacting intestinal immunity. Furthermore, exposure to APE increased LCT toxicity to zebrafish more than VPE. Meanwhile, exposure to PE-MPs and LCT alone or in combination has the potential to affect gut microbiota function and alter the abundance and diversity of the zebrafish gut flora. Collectively, the presence of PE-MPs may affect the toxicity of pesticides in zebrafish. The findings emphasize the importance of studying the interaction between MPs and pesticides in the aquatic environment.


Assuntos
Microbioma Gastrointestinal , Microplásticos , Nitrilas , Estresse Oxidativo , Polietileno , Piretrinas , Poluentes Químicos da Água , Peixe-Zebra , Animais , Piretrinas/toxicidade , Nitrilas/toxicidade , Microplásticos/toxicidade , Poluentes Químicos da Água/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Microbioma Gastrointestinal/efeitos dos fármacos , Polietileno/toxicidade , Adsorção
8.
Chem Biodivers ; : e202400721, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38639576

RESUMO

Two new nervogenic acid derivatives liparisnervosides Q (1) and R (5), as well as five known nervogenic acid derivatives (2-4, 6, 7) and four phenanthrenes (8-11) were isolated from the whole plant of Liparis nervosa (Thunb. ex A. Murray) Lindl.. Their structures were detremined using extensive spectroscopic techniques, including 1D, 2D NMR, and HR-ESI-MS, and acid hydrolysis. Furthermore, their antimicrobial and immunosuppressive activities were evaluated. Nervosine VII (3) exhibited antimicrobial activity against Staphylococcus aureus with an MIC of 62.5 µg/mL and inhibited the proliferation of human T cells with an IC50 value of 9.67±0.96 µM. These findings contribute to our understanding of the potential pharmacological properties of these compounds.

9.
Environ Sci Pollut Res Int ; 31(22): 32016-32032, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38642228

RESUMO

The interprovincial circulation of goods and services has formed virtual water flows between regions, which can redistribute water resources. Based on previous virtual water trade research, this study further explored the multiple dependencies of virtual water, i.e., direct, indirect, and complete dependence. This study examined the direct, indirect, and complete dependence of virtual water between provinces in China by constructing multilayer dependence networks and identified the key regions and paths of virtual water trade network. The results showed direct dependence was the densest and had the largest overall dependence degree, but indirect dependence was the most stable and orderly. Second, the dominant provinces were Guangxi, Hunan, Sichuan, Xinjiang, and Anhui, referred to as "core‒five‒region," and the flow relevant to them accounted for approximately 30% of the virtual water. The seven provinces of Shanxi, Zhejiang, Shandong, Hubei, Guangdong, Shaanxi, and Gansu depend both directly and indirectly on the "core‒five‒region." Shanxi and Zhejiang have close direct and indirect dependence, with more than one of the "core‒five‒region." Guangdong was the province with the most direct and indirect input of virtual water from the "core‒five‒region." The study provides a scientific basis for multiregional identification for the collaborative management of water resources in China from the perspective of dependence.


Assuntos
Recursos Hídricos , China , Abastecimento de Água , Água , Conservação dos Recursos Hídricos
10.
J Transl Med ; 22(1): 393, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38685045

RESUMO

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is a lethal malignancy with high probability of recurrence and distant metastasis. Liver metastasis is the predominant metastatic mode developed in most pancreatic cancer cases, which seriously affects the overall survival rate of patients. Abnormally activated endoplasmic reticulum stress and lipid metabolism reprogramming are closely related to tumor growth and metastasis. This study aims to construct a prognostic model based on endoplasmic reticulum stress and lipid metabolism for pancreatic cancer, and further explore its correlation with tumor immunity and the possibility of immunotherapy. METHODS: Transcriptomic and clinical data are acquired from TCGA, ICGC, and GEO databases. Potential prognostic genes were screened by consistent clustering and WGCNA methods, and the whole cohort was randomly divided into training and testing groups. The prognostic model was constructed by machine learning method in the training cohort and verified in the test, TCGA and ICGC cohorts. The clinical application of this model and its relationship with tumor immunity were analyzed, and the relationship between endoplasmic reticulum stress and intercellular communication was further explored. RESULTS: A total of 92 characteristic genes related to endoplasmic reticulum stress, lipid metabolism and liver metastasis were identified in pancreatic cancer. We established and validated a prognostic model for pancreatic cancer with 7 signatures, including ADH1C, APOE, RAP1GAP, NPC1L1, P4HB, SOD2, and TNFSF10. This model is considered to be an independent prognosticator and is a more accurate predictor of overall survival than age, gender, and stage. TIDE score was increased in high-risk group, while the infiltration levels of CD8+ T cells and M1 macrophages were decreased. The number and intensity of intercellular communication were increased in the high ER stress group. CONCLUSIONS: We constructed and validated a novel prognostic model for pancreatic cancer, which can also be used as an instrumental variable to predict the prognosis and immune microenvironment. In addition, this study revealed the effect of ER stress on cell-cell communication in the tumor microenvironment.


Assuntos
Estresse do Retículo Endoplasmático , Regulação Neoplásica da Expressão Gênica , Metabolismo dos Lipídeos , Neoplasias Hepáticas , Neoplasias Pancreáticas , Análise de Célula Única , Transcriptoma , Humanos , Estresse do Retículo Endoplasmático/genética , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Metabolismo dos Lipídeos/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/patologia , Transcriptoma/genética , Prognóstico , Masculino , Feminino , Pessoa de Meia-Idade , Perfilação da Expressão Gênica , Reprodutibilidade dos Testes , Estudos de Coortes
12.
Int J Biol Macromol ; 266(Pt 1): 131232, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38554896

RESUMO

Inflammatory bowel diseases (IBD) are chronic inflammatory conditions characterized by disruptions in the colonic mucus barrier and gut microbiota. In this study, a novel soluble polysaccharide obtained from Boletus aereus (BAP) through water extraction was examined for its structure. The protective effects of BAP on colitis were investigated using a DSS-induced mice model. BAP was found to promote the expression of intestinal mucosal and tight junction proteins, restore the compromised mucus barrier, and suppress the activation of inflammatory signaling. Moreover, BAP reshape the gut microbiota and had a positive impact on the composition of the gut microbiota by reducing inflammation-related microbes. Additionally, BAP decreased cytokine levels through the MANF-BATF2 signaling pathway. Correlation analysis revealed that MANF was negatively correlated with the DAI and the level of cytokines. Furthermore, the depletion of gut microbiota using antibiotic partially inhabited the effect of BAP on the activation of MANF and Muc2, indicating the role of gut microbiota in its protective effect against colitis. In conclusion, BAP had an obvious activation on MANF under gut inflammation. This provides new insights into the prospective use of BAP as a functional food to enhance intestinal health.


Assuntos
Colite , Sulfato de Dextrana , Microbioma Gastrointestinal , Mucina-2 , Transdução de Sinais , Animais , Microbioma Gastrointestinal/efeitos dos fármacos , Mucina-2/metabolismo , Mucina-2/genética , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/metabolismo , Camundongos , Transdução de Sinais/efeitos dos fármacos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Modelos Animais de Doenças , Polissacarídeos/farmacologia , Polissacarídeos/química , Citocinas/metabolismo , Basidiomycota/química , Masculino , Polissacarídeos Fúngicos/farmacologia , Polissacarídeos Fúngicos/química
13.
J Orthop Surg Res ; 19(1): 113, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38308347

RESUMO

BACKGROUND: This study employs an innovative closed reduction approach to treat pediatric "Irreducible Supracondylar Humerus Fractures" with the goal of demonstrating its practical application compared to conventional methods. METHODS: This study sampled 146 surgically treated cases of "Irreducible Supracondylar Humerus Fractures" in our department. After applying inclusion and exclusion criteria, 120 children were selected and divided into two groups based on treatment methods. Group 1 underwent Closed Reduction and Percutaneous Pinning (CRPP), while Group 2 received treatment using the Kirschner Wire Prying and Leverage Technique alongside CRPP. The relevant data to the study were collected and assessed during the follow-up period. RESULTS: Results indicate that Group 2 demonstrated significantly shorter operative times and fewer instances of intraoperative fluoroscopy compared to Group 1. Furthermore, the percentage of cases requiring open reduction was notably higher in Group 1 than in Group 2. The analysis also identified age, BMI, time from injury to surgery, and the initial deviation of the distal fragment as independent risk factors associated with the failure of closed reduction. The integration of CRPP with the Kirschner Wire Prying and Leverage Technique emerges as a safe and effective strategy for managing "Irreducible Supracondylar Humerus Fractures." This innovative approach not only reduces operative time and intraoperative fluoroscopy needs but also diminishes the reliance on open reduction without compromising safety.


Assuntos
Fios Ortopédicos , Fraturas do Úmero , Criança , Humanos , Fixação Interna de Fraturas/métodos , Estudos Retrospectivos , Úmero/cirurgia , Fraturas do Úmero/diagnóstico por imagem , Fraturas do Úmero/cirurgia , Resultado do Tratamento
14.
J Plast Reconstr Aesthet Surg ; 90: 189-191, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38394832

RESUMO

Preoperative selection of perforator is one of the key steps for successful surgery. The purpose of this study is to simulate the selection process of the perforator of the flap using the 3D models of the deep inferior epigastric artery (DIEA). A retrospective study was performed of women who underwent deep inferior epigastric perforator flap breast reconstruction from January 2011 to July 2021. Construct 3D models of the DIEA using computerized tomography angiography images, and then computational fluid dynamics simulations were performed. Correlation and regression analyses were used to analyze the geometric and hemodynamic parameters. Statistical analysis suggested that the outlet flow was positively correlated with the inlet area (r = 0.338, p = 0.000), outlet area (r = 0.840, p = 0.000), the average radius of the perforator (r = 0.592, p = 0.000), and negatively correlated with the length of perforator(r = -0.210, p = 0.024). The results of linear regression analysis showed that the outlet area (p = 0.000), the average radius (p = 0.000), and the length (p = 0.044) of the perforator were the influencing factors on outlet flow. In multiple perforators analysis, there was a significant difference in the total outlet flow among single perforator, double perforators, and triple perforators (p = 0.002). The successful implementation of this experiment provides a new approach for the selection of dominant perforators in the future.


Assuntos
Etilaminas , Mamoplastia , Retalho Perfurante , Humanos , Feminino , Estudos Retrospectivos , Imageamento Tridimensional , Artérias Epigástricas/diagnóstico por imagem , Retalhos Cirúrgicos/irrigação sanguínea , Mamoplastia/métodos , Retalho Perfurante/irrigação sanguínea
15.
Bioresour Technol ; 396: 130431, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38342279

RESUMO

Organic matter concentration is a critical factor influencing the adaptability of anaerobic ammonium oxidation (anammox) bacteria to low-strength sewage treatment. To address this challenge and achieve stable anammox activity, a micro-aeration partial nitrification-anammox process was developed for continuous-flow municipal sewage treatment. Under limited ammonium conditions, the effective utilization of organics in denitrification promoted the stable accumulation of nitrite and enhanced anammox activity. This, in turn, led to enhanced nitrogen removal efficiency, reaching approximately 87.7%. During the start-up phase, the protein content of extracellular polymeric substances (EPS) increased. This enhanced EPS intensified the inhibitory effect of denitrifying bacteria (DNB) on nitrite-oxidizing bacteria through competition for nitrite, thereby facilitating the proliferation of anammox bacteria (AnAOB). Additionally, several types of DNB capable of utilizing slowly biodegradable organics contributed to the adaptability of AnAOB. These findings provide valuable insights for ensuring efficient anammox performance and robust nitrogen removal in the treatment of low-strength sewage.


Assuntos
Compostos de Amônio , Esgotos , Esgotos/microbiologia , Desnitrificação , Nitritos/metabolismo , Anaerobiose , Reatores Biológicos/microbiologia , Oxirredução , Nitrificação , Compostos de Amônio/metabolismo , Nitrogênio/metabolismo , Bactérias/metabolismo
16.
Cancer Lett ; 587: 216649, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38311052

RESUMO

Pancreatic cancer is a highly malignant solid tumor with a poor prognosis and a high mortality rate. Thus, exploring the mechanisms underlying the development and progression of pancreatic cancer is critical for identifying targets for diagnosis and treatment. Two important hallmarks of cancer-metabolic remodeling and epigenetic reprogramming-are interconnected and closely linked to regulate one another, creating a complex interaction landscape that is implicated in tumorigenesis, invasive metastasis, and immune escape. For example, metabolites can be involved in the regulation of epigenetic enzymes as substrates or cofactors, and alterations in epigenetic modifications can in turn regulate the expression of metabolic enzymes. The crosstalk between metabolic remodeling and epigenetic reprogramming in pancreatic cancer has gained considerable attention. Here, we review the emerging data with a focus on the reciprocal regulation of metabolic remodeling and epigenetic reprogramming. We aim to highlight how these mechanisms could be applied to develop better therapeutic strategies.


Assuntos
Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Epigênese Genética
17.
Artigo em Inglês | MEDLINE | ID: mdl-38329855

RESUMO

Fluid flows in spherical coordinates have raised the interest of the graphics community in recent years. The majority of existing works focus on 2D manifold flows on a spherical shell, and there are still many unresolved problems for 3D simulations in spherical coordinates, such as boundary conditions for arbitrary obstacles and flexible artistic controls. In this paper, we propose a practical spherical-coordinate simulator for flow motions in 3D domains. Based on a layer-by-layer structure and a boundary-aware pressure solving scheme, we are able to recover horizontal and vertical flow motions in the presence of arbitrary terrain shapes within a spherical shell of finite thickness. Our proposed method straightforwardly builds on the conventions of previous 2D-manifold spherical-coordinate simulations and provides flexible artistic control strategies for art design.

18.
J Org Chem ; 89(5): 3390-3402, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-38377557

RESUMO

The introduction of alkyne moieties into peptides remains in demand as it represents a promising approach for further structural diversification of peptides. Herein, we describe the Pd(II)-catalyzed C(sp3)-H alkynylation of Ala-Asn-embedded di- and tripeptides using Asn as the endogenous lead group. In addition, a key building block for the glycopeptide Tyc4PG-14 and Tyc4PG-15 was produced by our methodology.


Assuntos
Alanina , Alcinos , Glicopeptídeos , Catálise
19.
One Health ; 18: 100688, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38317850
20.
MedComm (2020) ; 5(2): e495, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38374872

RESUMO

Epigenetic modifications are defined as heritable changes in gene activity that do not involve changes in the underlying DNA sequence. The oncogenic process is driven by the accumulation of alterations that impact genome's structure and function. Genetic mutations, which directly disrupt the DNA sequence, are complemented by epigenetic modifications that modulate gene expression, thereby facilitating the acquisition of malignant characteristics. Principals among these epigenetic changes are shifts in DNA methylation and histone mark patterns, which promote tumor development and metastasis. Notably, the reversible nature of epigenetic alterations, as opposed to the permanence of genetic changes, positions the epigenetic machinery as a prime target in the discovery of novel therapeutics. Our review delves into the complexities of epigenetic regulation, exploring its profound effects on tumor initiation, metastatic behavior, metabolic pathways, and the tumor microenvironment. We place a particular emphasis on the dysregulation at each level of epigenetic modulation, including but not limited to, the aberrations in enzymes responsible for DNA methylation and histone modification, subunit loss or fusions in chromatin remodeling complexes, and the disturbances in higher-order chromatin structure. Finally, we also evaluate therapeutic approaches that leverage the growing understanding of chromatin dysregulation, offering new avenues for cancer treatment.

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