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1.
Chin J Integr Med ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38990478

RESUMO

Atrial fibrillation (AF) is the most common arrhythmia in clinical practice. It has a high prevalence and poor prognosis. The application of antiarrhythmic drugs and even surgery cannot completely treat the disease, and there are many sequelae. AF can be classified into the category of "palpitation" in Chinese medicine according to its symptoms. Acupuncture has a significant effect on AF. The authors find that an important mechanism of acupuncture in AF treatment is to regulate the cardiac vagus nerve. Therefore, this article intends to review the distribution and function of vagus nerve in the heart, the application and the regulatroy effect for the treatment of AF.

2.
J Pharm Biomed Anal ; 249: 116339, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-39024794

RESUMO

Codonopsis Radix (CR), a traditional tonic medicinal material in China, has been proven to possess a variety of bioactive functions. However, its chemical composition and in vivo metabolic pattern have not been fully elucidated. In this study, AB-8 macroporous resin column chromatography was employed for the enrichment of small molecular components in CR. Furthermore, a method combining ultra-performance liquid chromatography-quadrupole-orbitrap mass spectrometry with Acquire X intelligent data acquisition technology software was developed for the preliminary screening and identification of the chemical composition of CR in vitro and their metabolites in vivo. As a result, a total of 116 components were preliminarily characterized in the CR extract, including 28 polyacetylenes, 33 organic acids, 4 amino acids, 23 alkaloids, 9 phenylpropanoids, 6 terpenoids, 2 nucleosides, and 11 others. Additionally, a total of 84 compounds, including 37 prototype components and 47 metabolites, were identified in the plasma, urine, and feces of rats after oral administration of CR. Specifically, 11, 24, 19, 32, and 25 constituents were identified in the heart, liver, spleen, lung, and kidney, respectively. Of note, the lung and spleen are the organs with the highest distribution of CR compounds. These findings will serve as valuable data for future research on the correlation between the chemical composition and pharmacological effects of CR.

3.
J Chromatogr A ; 1730: 465173, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39025024

RESUMO

A dipeptide-based bifunctional material immobilized with Ti4+ (denoted as APE-MBA-VPA-Ti4+) was developed using precipitation polymerization. This polymer combines hydrophilic interaction liquid chromatography (HILIC) and immobilized metal affinity chromatography (IMAC) enrichment strategies, allowing for the individual and simultaneous enrichment of glycopeptides and phosphopeptides. It demonstrated high sensitivity (0.1 fmol µL-1 for glycopeptides, 0.005 fmol µL-1 for phosphopeptides), strong selectivity (molar ratio HRP: BSA = 1:1000, ß-casein: BSA = 1:2500), consistent reusability (10 cycles) and satisfactory recovery rate (93.5 ± 1.8 % for glycopeptides, 91.6 ± 0.6 % for phosphopeptides) in the individual enrichment. Utilizing nano LC-MS/MS technology, the serum of liver cancer patients was analyzed after enrichment individually, resulting in the successful capture of 333 glycopeptides covering 262 glycosylation sites, corresponding to 131 glycoproteins, as well as 67 phosphopeptides covering 57 phosphorylation sites, related to 48 phosphoproteins. In comparison, the serum of normal healthy individuals yielded a total of 283 glycopeptides covering 244 glycosylation sites corresponding to 126 glycoproteins, as well as 66 phosphopeptides covering 56 phosphorylation sites related to 37 phosphoproteins. Label-free quantification identified 10 differentially expressed glycoproteins and 8 differentially expressed phosphoproteins in the serum of liver cancer patients. Among them, glycoproteins (HP, BCHE, AGT, C3, and PROC) and phosphoproteins (ZYX, GOLM1, GP1BB, CLU, and TNXB) showed upregulation and displayed potential as biomarkers for liver cancer.

4.
Int J Nanomedicine ; 19: 6377-6397, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38952677

RESUMO

Background: How to ingeniously design multi-effect photosensitizers (PSs), including multimodal imaging and multi-channel therapy, is of great significance for highly spatiotemporal controllable precise phototherapy of malignant tumors. Methods: Herein, a novel multifunctional zinc(II) phthalocyanine-based planar micromolecule amphiphile (ZnPc 1) was successfully designed and synthesized, in which N atom with photoinduced electron transfer effect was introduced to enhance the near-infrared absorbance and nonradiative heat generation. After simple self-assembling into nanoparticles (NPs), ZnPc 1 NPs would exhibit enhanced multimodal imaging properties including fluorescence (FL) imaging (FLI) /photoacoustic (PA) imaging (PAI) /infrared (IR) thermal imaging, which was further used to guide the combined photodynamic therapy (PDT) and photothermal therapy (PTT). Results: It was that under the self-guidance of the multimodal imaging, ZnPc 1 NPs could precisely pinpoint the tumor from the vertical and horizontal boundaries achieving highly efficient and accurate treatment of cancer. Conclusion: Accordingly, the integration of FL/PA/IR multimodal imaging and PDT/PTT synergistic therapy pathway into one ZnPc 1 could provide a blueprint for the next generation of phototherapy, which offered a new paradigm for the integration of diagnosis and treatment in tumor and a promising prospect for precise cancer therapy.


Assuntos
Indóis , Isoindóis , Imagem Multimodal , Nanopartículas , Fotoquimioterapia , Fármacos Fotossensibilizantes , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Imagem Multimodal/métodos , Animais , Humanos , Indóis/química , Indóis/farmacologia , Fotoquimioterapia/métodos , Nanopartículas/química , Camundongos , Compostos de Zinco/química , Compostos Organometálicos/química , Compostos Organometálicos/farmacologia , Linhagem Celular Tumoral , Técnicas Fotoacústicas/métodos , Terapia Fototérmica/métodos , Neoplasias/diagnóstico por imagem , Neoplasias/terapia , Neoplasias/tratamento farmacológico , Camundongos Endogâmicos BALB C , Fototerapia/métodos , Feminino
5.
Int J Food Microbiol ; 422: 110808, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38955022

RESUMO

Salmonella contamination of pork products is a significant public health concern. Temperature abuse scenarios, such as inadequate refrigeration or prolonged exposure to room temperature, can enhance Salmonella proliferation. This study aimed to develop and validate models for Salmonella growth considering competition with background microbiota in raw ground pork, under isothermal and dynamic conditions of temperature abuse between 10 and 40 °C. The maximum specific growth rate (µmax) and maximum population density (MPD) were estimated to quantitatively describe the growth behavior of Salmonella. To reflect more realistic microbial interactions in Salmonella-contaminated product, our model considered competition with the background microbiota, measured as mesophilic aerobic plate counts (APC). Notably, the µmax of Salmonella in low-fat samples (∼5 %) was significantly higher (p < 0.05) than that in high-fat samples (∼25 %) at 10, 20, and 30 °C. The average doubling time of Salmonella was 26, 4, 2, 1.5, 0.8, and 1.1 h at 10, 15, 20, 25, 30, and 40 °C, respectively. The initial concentration of Salmonella minimally impacted its growth in ground pork at any temperature. The MPD of APC consistently exceeded that of Salmonella, indicating the growth of APC without competition from Salmonella. The competition model exhibited excellent fit with the experimental data, as 95 % (627/660) of residual errors fell within the desired acceptable prediction zone (pAPZ >0.70). The theoretical minimum and optimum growth temperatures for Salmonella ranged from 5 to 6 °C and 35 to 36 °C, respectively. The dynamic model displayed strong predictive performance, with 90 % (57/63) of residual errors falling within the APZ. Dynamic models could be valuable tools for validating and refining simpler static or isothermal models, ultimately improving their predictive capabilities to enhance food safety.

6.
Proteins ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958516

RESUMO

The ongoing global pandemic of the coronavirus 2019 (COVID-19) disease is caused by the virus SARS-CoV-2, with very few highly effective antiviral treatments currently available. The machinery responsible for the replication and transcription of viral RNA during infection is made up of several important proteins. Two of these are nsp12, the catalytic subunit of the viral polymerase, and nsp9, a cofactor of nsp12 involved in the capping and priming of viral RNA. While several recent studies have determined the structural details of the interaction of nsp9 with nsp12 in the context of RNA capping, very few biochemical or biophysical details are currently available. In this study, we have used a combination of surface plasmon resonance (SPR) experiments, size exclusion chromatography (SEC) experiments, and biochemical assays to identify specific nsp9 residues that are critical for nsp12 binding as well as RNAylation, both of which are essential for the RNA capping process. Our data indicate that nsp9 dimerization is unlikely to play a significant functional role in the virus. We confirm that a set of recently discovered antiviral peptides inhibit nsp9-nsp12 interaction by specifically binding to nsp9; however, we find that these peptides do not impact RNAylation. In summary, our results have important implications for future drug discovery efforts to combat SARS-CoV-2 and any newly emerging coronaviruses.

7.
Beijing Da Xue Xue Bao Yi Xue Ban ; 56(4): 640-645, 2024 Dec 18.
Artigo em Chinês | MEDLINE | ID: mdl-39041559

RESUMO

OBJECTIVE: To investigate the feasibility, safety and effectiveness of robot-assisted laparoscopic buccal mucosa graft ureteroplasty in the treatment of complex long proximal ureteral stricture. METHODS: The clinical data of 20 patients with proximal ureteral stricture undergoing robot-assisted laparoscopic buccal mucosa graft ureteroplasty admitted to the Department of Urology, Peking University First Hospital and Beijing Jiangong Hospital from July 2022 to January 2023 were prospectively collected and analyzed. Intraoperative conditions, postoperative complications and follow-up data were also recorded and analyzed. RESULTS: The operations under robot-assisted laparoscopy were performed successfully in all the 20 patients without conversion to traditional laparoscopic surgery or open surgery. The study included 14 males and 6 females with a mean age of (41±11) years (range: 19 to 60 years) and a mean body mass index of (24.3±3.6) kg/m2 (range: 18.2 to 31.8 kg/m2). There were 9 cases on the left side and 11 cases on the right side. The strictures of all the patients were located in the proximal segment of the ureter (including the ureteropelvic junction). The mean preoperative serum creatinine was (92.2±23.3) µmol/L (range: 49.2 to 138.9 µmol/L), and the mean length of ureteral stricture was (2.8±0.9) cm (range: 1.0 to 4.0 cm). Ten patients had previously undergone unsuccessful reconstructive surgery. During the operation, 12 patients received posteriorly augmented anastomosis with ventral onlay. The mean length of the buccal mucosa graft harvested during the operation was (3.1±0.6) cm (range: 2.0 to 4.3 cm), and the median width was 1.5 cm (range: 1.0 to 2.0 cm). The omentum flap was used to wrap the reconstructed ureteral segment in all the 20 cases. The median operative time was 154 min (range: 113 to 300 min), and the median estimated blood loss was 45 mL (range: 0 to 100 mL). The median postoperative hospital stay was 4 d (range: 4 to 14 d). The mean postoperative follow-up time was (15.0±1.7) months (range: 12.5 to 17.9 months), and the surgical success rate was 100.0% in this study. After surgery, 11 patients reported mild discomfort at the oral donor site, 2 patients deve-loped urinary tract infection, and no postoperative complications were reported in the other 7 patients. The mean serum creatinine was (90.9±23.9) µmol/L (range: 60.0 to 153.0 µmol/L) six months after surgery. CONCLUSION: Robot-assisted laparoscopic buccal mucosa graft ureteroplasty for the treatment of complex long proximal ureteral stricture has satisfactory efficacy without severe complications, which has shown good feasibility, safety and effectiveness. However, large sample studies and long-term follow-up are still needed to evaluate its long-term efficacy.


Assuntos
Laparoscopia , Mucosa Bucal , Procedimentos Cirúrgicos Robóticos , Ureter , Obstrução Ureteral , Humanos , Masculino , Feminino , Adulto , Mucosa Bucal/transplante , Pessoa de Meia-Idade , Laparoscopia/métodos , Procedimentos Cirúrgicos Robóticos/métodos , Obstrução Ureteral/cirurgia , Ureter/cirurgia , Adulto Jovem , Constrição Patológica , Procedimentos Cirúrgicos Urológicos/métodos , Duração da Cirurgia , Complicações Pós-Operatórias/etiologia , Procedimentos de Cirurgia Plástica/métodos
8.
Nucleic Acids Res ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38989619

RESUMO

The type III-A (Csm) CRISPR-Cas systems are multi-subunit and multipronged prokaryotic enzymes in guarding the hosts against viral invaders. Beyond cleaving activator RNA transcripts, Csm confers two additional activities: shredding single-stranded DNA and synthesizing cyclic oligoadenylates (cOAs) by the Cas10 subunit. Known Cas10 enzymes exhibit a fascinating diversity in cOA production. Three major forms-cA3, cA4 and cA6have been identified, each with the potential to trigger unique downstream effects. Whereas the mechanism for cOA-dependent activation is well characterized, the molecular basis for synthesizing different cOA isoforms remains unclear. Here, we present structural characterization of a cA6-producing Csm complex during its activation by an activator RNA. Analysis of the captured intermediates of cA6 synthesis suggests a 3'-to-5' nucleotidyl transferring process. Three primary adenine binding sites can be identified along the chain elongation path, including a unique tyrosine-threonine dyad found only in the cA6-producing Cas10. Consistently, disrupting the tyrosine-threonine dyad specifically impaired cA6 production while promoting cA4 production. These findings suggest that Cas10 utilizes a unique enzymatic mechanism for forming the phosphodiester bond and has evolved distinct strategies to regulate the cOA chain length.

9.
Mol Cell Proteomics ; : 100810, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38977202

RESUMO

Transcriptionally and translationally silent sperm undergo functional maturation during epididymis traverse, which provides sperm ability to move and is crucial for successful fertilization. However, the molecular mechanisms governing sperm maturation remain poorly understood, especially at protein post-translational modification level. In this study, we conducted a comprehensive quantitative phosphoproteomic analysis of mouse epididymal sperm from different regions (caput, corpus, and cauda) to unveil the dynamics of protein phosphorylation during sperm maturation. We identified 6,447 phosphorylation sites in 1,407 phosphoproteins, and 345 phosphoproteins were differentially phosphorylated between caput and cauda sperm. Gene ontology and KEGG pathway analyses showed enrichment of differentially phosphorylated proteins in energy metabolism, sperm motility and fertilization. Kinase substrate network analysis followed by inhibition assay and quantitative phosphoproteomics analysis showed that TSSK2 kinase is important for sperm motility and progressive motility. This study systemically characterized the intricate phosphorylation regulation during sperm maturation in the mouse epididymis, which can be a basis to elucidate sperm motility acquisition, and to offer potential targets for male contraception and the treatment of male infertility.

10.
Artigo em Inglês | MEDLINE | ID: mdl-38949761

RESUMO

BACKGROUND: Sjogren's Syndrome (SS) plays important roles in the development of essential hypertension. Nevertheless, with the limitation of reverse causality and confounder in observational studies, such a relationship remains unclear. We aimed to assess the causal relationship of SS and hypertension by the Mendelian randomization (MR) approach. METHODS: We used MR to investigate a causal association between SS and essential hypertension. Inverse variance weighted (IVW), MR Egger regression, Maximum likelihood, Weighted median, and MR pleiotropy residual sum and outlier test (MR-PRESSO) were used in this MR analysis. RESULTS: In this study, we found that the ratio of IVW is 1.00024 (95% CI: 1.00013- 1.00036, P=0.0387), This result was also confirmed by sensitivity analysis methods such as Maximum likelihood is 1.00025 (95% CI: 1.00013-1.00037, P=0.036), MR Egger is 1.00071 (95% CI: 1.00047-1.00095, P=0.0045), and Weighted median is 1.00040 (95% CI: 1.00021- 1.00059, P=0.0322). And MR-Egger intercept method revealed the absence of horizontal pleiotropy in this investigation (P>0.05). The Cochran's Q Test indicated an absence of heterogeneity among them (P>0.05). Heterogeneity and horizontal pleiotropy tests further demonstrate that the results of MR are relatively stable. The above results all suggest that pSS may promote the risk of hypertension. CONCLUSIONS: Our study provides evidence of a causal relationship of SS and hypertension. It is suggested to pay attention to early screening for hypertension, reduce disability and mortality rates, and improve patient prognosis in patients with SS.

11.
Artigo em Inglês | MEDLINE | ID: mdl-39052538

RESUMO

Anti-counterfeiting technology has always been a key issue in the field of information security. Physical Unclonable Function (PUF) labels, which are random patterns produced by a stochastic process, emerge as an effective anti-counterfeiting strategy due to the inherent randomness of their physical patterns. In this study, we developed a high-throughput droplet array generation technique based on surface tension confinement to prepare perovskite crystal films with controllable shapes and sizes. We utilized the random distribution of perovskite nanocrystal particles to construct the PUF textures of the labels. Compared to other anti-counterfeiting labels, our labels not only possess fluorescent properties but also feature microscale dimensions (less than 5.3 × 10-2mm2), low cost (less than 3 × 10-4 USD), and high encoding capacity (1.7 × 101956), providing support for multilevel anti-counterfeiting protection. Additionally, we introduce an innovative PUF recognition method based on a Partial Convolutional Network (PaCoNet), effectively addressing the limitations of previous methods, in terms of recognition accuracy and speed. Experimental validation on a data set of perovskite nanocrystal films with up to 60 different macroscopic shapes and unique microscopic textures demonstrates that our method achieves a recognition accuracy of up to 99.65% and significantly reduces the recognition time per image to just 0.177 s, highlighting the potential application of these labels in the field of anti-counterfeiting.

12.
Int Immunopharmacol ; 139: 112738, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39053232

RESUMO

BACKGROUND: Rheumatoid arthritis, a condition characterized by inflammation, has a substantial influence on both the worldwide economy and public health. Prior studies indicate that probiotics have the potential to enhance the composition of gut microbiota in instances of intestinal dysbiosis resulting from different disorders and contribute to the regulation of inflammation. The objective of this study is to investigate the impact of Saccharomyces boulardii on the gut microbiome in arthritis and its implications on inflammation. METHODS: The study utilized the Collagen Induced Arthritis (CIA) Sprague-Dawley (SD) rat model. After administering Saccharomyces boulardii (150 mg/kg/day) six days a week and Methotrexate (MTX) (0.2 mg/week) treatment for eight weeks, microbial DNA from the feces was sequenced using 16S rRNA. The evaluation of histopathology, bone loss, and cartilage degradation was conducted using histology, immunohistology assays, and micro-computed tomography (µCT) examinations. The enzyme-linked immunosorbent assay (ELISA) was used to analyze proinflammatory cytokines, while the western blot technique was applied to detect protein in the gut and in cell lines. The quantification of gene expression in gut,joint and cell lines was performed using real-time polymerase chain reaction. The cell lines were activated and then treated with the culture supernatant of S. boulardii for an in vitro investigation. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test was utilized to assess cell proliferationand viability. Cellular motility was measured in a wound healing experiment, whereas apoptotic proteins were analyzed using Western blotting. RESULTS: S. boulardii has been found to enhance bone and joint integrity, modulate gut microbiota, and mitigate proinflammatory cytokine levels in rats with arthritis. It decreases the permeability of the intestines and promotes the production of gut tight-junction proteins. The administration of S. boulardii inhibits the proliferation of T-helper-17 (Th17) and Type 3 innate lymphoid cells (ILC3). Additionally, it elicits apoptosis in MH7A cell lines and hinders their migratory activity. CONCLUSION: This study provides valuable insights into the therapeutic potential of S. boulardii for treating and preventing arthritis in rats with collagen-induced arthritis by modulating gut microbiota and inflammation.

13.
Environ Res ; : 119641, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39053757

RESUMO

Mercury (Hg), especially methylmercury (MeHg), is a pervasive contaminant that poses significant risks to birds occupying high trophic levels. However, we have little knowledge about the mercury exposure and its risks for birds in Poyang Lake basin, China. Therefore, during 2020-2021, we investigated MeHg concentrations in breast feathers of wintering migratory birds (n=430 from 43 species belonging to 9 orders) in Poyang Lake Nanji Wetland and Jiangxi Nanfengmian National Nature Reserve, China. MeHg concentrations in breast feathers varied greatly by species, foraging guilds and taxonomic orders, among which the highest concentration was detected in great egret (8849 ± 5975 ng g-1 dw). Comparing with studies worldwide, high MeHg concentrations in feathers of Ardeidae from Pelecaniformes were found in this area. Moreover, herons migrating between northern and southern China had lower MeHg concentration than residents in southern China related to habitat Hg. Considering the applicability and sensitivity of the equations for the transformation of MeHg concentrations in feathers to blood-equivalent total Hg (THg) values, method CJ that the equation based on songbirds was used for the transformation of the songbirds and the equation based on seabirds for the others performed better than other three for risk assessment of bird Hg in this study. 23.1% of birds from Poyang Lake were at risk of Hg exposure based on the method CJ. Carnivorous birds from Pelecaniformes had the highest risk levels, with 37.2% categorized as no risk (≤ 200 ng g-1 ww), 48.9% as low risk (200∼1000 ng g-1 ww), 11.1% as moderate risk (1000∼3000 ng g-1 ww), 1.1% as high risk (3000∼4000 ng g-1 ww), and 1.7% as severe risk (> 4000 ng g-1 ww). These risks suggest long-term monitoring and further advanced studies about freshwater waterbirds Hg exposure is necessary.

14.
Sci Prog ; 107(3): 368504241266559, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39043384

RESUMO

Ceramic-added air lime mortars have been used since ancient times owing to the pozzolanic effect provided by crushed ceramic particles that impart hydraulic properties. This work reviews the historical use, composition, reaction mechanisms, characterization techniques, and performance properties of ceramic-added air lime mortars. The fine ceramic powder composed of silica and alumina phases reacts with calcium hydroxide released during lime hydration to form calcium silicate hydrates (CSH) and calcium aluminate hydrates (CAH) via pozzolanic reaction. This provides hydraulicity and reduces setting time compared to pure air lime mortars. The coarser ceramic particles also serve as aggregate and refine the microstructure as filler. The reactivity depends on the ceramic composition, amorphous phase content, particle size distribution, and firing temperature. Optimal proportioning of the fine ceramic powder and coarse ceramic aggregate is necessary to achieve desired properties. Ceramic addition enhances the durability of air lime mortars against weathering while maintaining compatibility with lime-based masonry structures. Key novelties of this review include: (i) in-depth analysis of the influence of ceramic characteristics (mineralogy, particle size, pozzolanicity) and processing on reaction kinetics and phase evolution; (ii) systematic assessment of mechanical, physical and durability properties in comparison to conventional air lime mortars and cement-based grouts; (iii) elucidation of microstructural mechanisms governing performance using advanced characterization techniques; (iv) critical appraisal of test methods and standards for evaluation; and (v) rigorous discussion on potential applications in construction, conservation and repair, with case studies.

15.
Mol Med Rep ; 30(3)2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39054969

RESUMO

Following the publication of this paper, it was drawn to the Editors' attention by a concerned reader that certain of the JC­1 staining images in Fig. 2C were strikingly similar to data appearing in different form in other articles written by different authors at different research institutes that had either already been published elsewhere prior to the submission of this paper to Molecular Medicine Reports, or were under consideration for publication at around the same time (a small number of which have been retracted). In addition, the Snail western blot data in Fig. 3E bore a close similarity to certain of the Mfn2 data shown in Fig. 4A. In view of the fact that certain of the contentious data had already apparently been published previously, and owing to a lack of confidence in the presentation of certain of the data in this paper, the Editor of Molecular Medicine Reports has decided that this paper should be retracted from the Journal. The authors were asked for an explanation to account for these concerns, but the Editorial Office did not receive a reply. The Editor apologizes to the readership for any inconvenience caused. [Molecular Medicine Reports 22: 398­404, 2020; DOI: 10.3892/mmr.2020.11098].

16.
ACS Sustain Chem Eng ; 12(26): 9822-9832, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38966239

RESUMO

Oxalate esters and isosorbide serve as intriguing polymer building blocks, as they can be sourced from renewable resources, such as CO2 and glucose, and the resulting polyesters offer outstanding material properties. However, the low reactivity of the secondary hydroxyl groups makes it difficult to generate high-molecular-weight polymers from isosorbide. Combining diaryl oxalates with isosorbide appears to be a promising approach to produce high-molecular-weight isosorbide-based polyoxalates (PISOX). This strategy seems to be scalable, has a short polymerization time (<5 h), and uniquely, there is no need for a catalyst. PISOX demonstrates outstanding thermal, mechanical, and barrier properties; its barrier to oxygen is 35 times better than PLA, it possesses mechanical properties comparable to high-performance thermoplastics, and the glass transition temperature of 167 °C can be modified by comonomer incorporation. What makes this high-performance material truly exceptional is that it decomposes into CO2 and biomass in just a few months in soil under home-composting conditions and it hydrolyzes without enzymes present in less than a year in 20 °C water. This unique combination of properties has the potential to be utilized in a range of applications, such as biomedical uses, water-resistant coatings, compostable plastic bags for gardening and agriculture, and packaging plastics with diminished environmental impact.

18.
J Environ Manage ; 366: 121594, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38971061

RESUMO

In the management of urban drainage networks, great interest has been generated in the removal of sediments from sewer systems. The unsteady three-dimensional (3D) flow and turbulent coherent structures surrounding sediment reduction plates in a sewer system are investigated by means of the detached-eddy simulation (DES). Particular emphasis is given to detailing the instantaneous velocity and vorticity fields within the grooves, along with an examination of the three-dimensional, long-term, average flow structure at a Reynolds number of approximately 105. Velocity vectors demonstrate continuous flapping of the flow on the groove wall, periodically interacting with ejections of positive and negative vorticity originating from the grooves. The interaction between the three-dimensional groove flow and the shear flow leads to the downstream transport of patches of positive and negative vorticity, which significantly influence sediment transport. The high-velocity shear flows and strong vortices generated in undulating topography, as identified by the Q-criteria, are the key factors contributing to the efficient sediment reduction capabilities of the sediment reduction plates. The sediment reduction plates with partially enclosed structures exhibit low sedimentation rates in grooves on the plate, a broader acceleration region, and a lesser impact on the flow capacity. The results improve the understanding of the hydrodynamics and turbulent coherent structures surrounding the sediment reduction plates while elucidating the driving factors behind the enhancement of sediment scouring and suspension capacities. These results indicate that the redesign of the plates as partially enclosed structures contributes to further improving their sediment reduction performance.

19.
Environ Sci Technol ; 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39012186

RESUMO

Atmospheric transport drives the widespread distribution of microplastic (MP) in various ecosystems, posing a growing potential threat to environmental safety and human health. Understanding the source and fate of atmospheric MPs is thus crucial to constrain MP's widespread exposure. However, the source-sink dynamics of atmospheric MPs, especially in remote areas, are uncertain, and their transport routes have yet to be identified. Here, we conducted a 13-month monitoring of the atmospheric MPs in the uninhabited area of Mount Taibai, estimated the potential risk of MP exposure to the environment, and modeled the MP trajectory to analyze their transportation. We first found that as many as 15 polymer types of MPs, whose shapes mainly include fiber, fragments, films, and granules, maintained abundance (0.7 and 0.3 particle/m3 for PM10 and PM2.5, respectively) in the mountain atmosphere at respirable sizes. It is worth noting that the risk assessment results that comprehensively consider the influences of abundance and morphological characteristics suggest that the exposure level of MPs exhibits a risk even in this remote mountainous area that is not disturbed by frequent human activities. Backward trajectories revealed the likely source of MPs in the sparsely populated Liupan Mountains and Qinling Mountains of short-range transport. Further, polymer characteristics of MPs and airflow-based source analysis indicated the emission source of MPs in southern Xianyang in a longer-range transport. MPs were directionally transported to Mount Taibai through atmospheric transport under the premise of stable climate and geographical conditions. These suggest that MPs inevitably occur in remote mountainous areas driven by atmospheric transport, and the mountainous areas are persistently bearing the environmental impact of MP exposure. This study reveals the risk impacts of MP exposure and the transport dynamics of atmospheric MPs in a mountain ecosystem.

20.
Bioorg Med Chem Lett ; : 129890, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39004317

RESUMO

This study reports the design, synthesis, and comprehensive biological evaluation of 13 benzodioxolane derivatives, derived from the core structure of piperine, a natural product with established antitumor properties. Piperine, primarily found in black pepper, has been noted for its diverse pharmacological activities, including anti-inflammatory, antioxidant, and anticancer effects. Leveraging piperine's antitumor potential, we aimed to enhance its efficacy through structural modifications. Among the synthesized compounds, HJ1 emerged as the most potent, exhibiting a 4-fold and 10-fold increase in inhibitory effects on HeLa and MDA-MB-231 cell lines, respectively, compared to piperine. Furthermore, HJ1 demonstrated a favorable safety profile, characterized by significantly lower cytotoxicity towards the human normal cell line 293T. Mechanistic investigations revealed that HJ1 markedly inhibited clonogenicity, migration, and adhesion of HeLa cells. In vivo studies utilizing the chick embryo chorioallantoic membrane (CAM) model substantiated the robust antitumor activity of HJ1, evidenced by its ability to suppress tumor angiogenesis and reduce tumor weight. These results suggest that HJ1 holds significant promise as a lead compound for the development of novel antitumor therapies.

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