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1.
Molecules ; 29(7)2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38611743

RESUMO

Benzene is the typical volatile organic compound (VOC) of indoor and outdoor air pollution, which harms human health and the environment. Due to the stability of their aromatic structure, the catalytic oxidation of benzene rings in an environment without an external energy input is difficult. In this study, the efficient degradation of benzene at room temperature was achieved by constructing Ag and Ni bimetallic active site catalysts (AgNi/BCN) supported on boron-carbon-nitrogen aerogel. The atomic-scale Ag and Ni are uniformly dispersed on the catalyst surface and form Ag/Ni-C/N bonds with C and N, which were conducive to the catalytic oxidation of benzene at room temperature. Further catalytic reaction mechanisms indicate that benzene reacted with ·OH to produce R·, which reacted with O2 to regenerate ·OH. Under the strong oxidation of ·OH, benzene was oxidized to form alcohols, carboxylic acids, and eventually CO2 and H2O. This study not only significantly reduces the energy consumption of VOC catalytic oxidation, but also improves the safety of VOC treatment, providing new ideas for the low energy consumption and green development of VOC treatment.

2.
Environ Res ; 252(Pt 2): 118842, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38583656

RESUMO

This study investigates the distribution of rare earth elements (REEs) within the Beijing water system, specifically examining the Yongding, Chaobai, Beiyun, Jiyun, and Daqing rivers. Results indicate that the Beiyun River exhibits the highest REE concentrations, ranging from 35.95 to 59.78 µg/mL, while the Daqing River shows the lowest concentrations, ranging from 15.79 to 17.48 µg/mL. LREEs (La to Nd) predominate with a total concentration of 23.501 µg/mL, leading to a notable LREE/HREE ratio of 7.901. Positive Ce anomalies (0.70-1.11) and strong positive Eu anomalies (1.38-2.49) were observed. The study suggests that the Beijing water system's REEs may originate from geological and anthropogenic sources, such as mining and industrial activities in neighboring regions, including Inner Mongolia. These findings underscore the importance of ongoing monitoring and effective water management strategies to address REE-related environmental concerns.

3.
ACS Appl Bio Mater ; 7(4): 2544-2553, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38507285

RESUMO

The poor accumulation of antibiotics in the cytoplasm leads to the poor eradication of intracellular bacteria. Herein, a polyelectrolyte complex (PECs@Rif) allowing direct cytosolic delivery of rifampicin (Rif) was developed for the treatment of intracellular infections by complexation of poly(α-lipoic acid) (pLA) and oligosaccharide (COS) in water and loading Rif. Due to the thiol-mediated cellular uptake, PECs@Rif delivered 3.9 times higher Rif into the cytoplasm than that of the free Rif during 8 h of incubation. After entering cells, PECs@Rif released Rif by dissociating pLA into dihydrolipoic acid (DHLA) in the presence of intracellular thioredoxin reductase (TrxR). Notably, DHLA could reduce endogenous Fe(III) to Fe(II) and provide a catalyst for the Fenton reaction to produce a large amount of reactive oxygen species (ROS), which would assist Rif in eradicating intracellular bacteria. In vitro assay showed that PECs@Rif reduced almost 2.8 orders of magnitude of intracellular bacteria, much higher than 0.7 orders of magnitude of free Rif. The bacteremia-bearing mouse models showed that PECs@Rif reduced bacterial levels in the liver, spleen, and kidney by 2.2, 3.7, and 2.3 orders of magnitude, respectively, much higher than free Rif in corresponding tissues. The direct cytosolic delivery in a thiol-mediated manner and enhanced oxidative stress proposed a feasible strategy for treating intracellular bacteria infection.


Assuntos
Compostos Férricos , Rifampina , Camundongos , Animais , Rifampina/farmacologia , Polieletrólitos , Estresse Oxidativo , Bactérias
4.
Environ Sci Pollut Res Int ; 31(17): 26089-26098, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38492135

RESUMO

Polybrominated diphenyl ethers (PBDEs) are toxic to organisms with melatonin (MT) providing protection for tissues and cells against these. This study investigates the mechanism of damage of 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) and the cellular protection of MT on grass carp hepatocytes. Grass carp hepatocytes were exposed to 25 µmol/L BDE-47 and/or 40 µmol/L MT for 24 h before testing. Acridine orange/ethidium bromide (AO/EB) double fluorescence staining results showed that BDE-47 could induce cell apoptosis. The expression levels of the endoplasmic reticulum (ER) stress-related genes ire1, atf4, grp78, perk, and chop were also significantly up-regulated (P < 0.01). The levels of the apoptosis-related genes caspase3, bax, and caspase9 were significantly up-regulated (P < 0.0001), while the level of bcl-2 was significantly down-regulated (P < 0.01). Compared with the BDE-47 group, the BDE-47 + MT group showed reduced levels of ER and apoptosis of hepatocytes, while the expression of the ER stress-related genes ire1, atf4, grp78, perk, and chop and the apoptosis-related genes caspase3, bax, and caspase9 were down-regulated (P < 0.05), and the level of bcl-2 was up-regulated (P < 0.01). In conclusion, BDE-47 can activate ER and apoptosis in grass carp hepatocytes, while MT can reduce these responses.


Assuntos
Carpas , Melatonina , Animais , Éteres Difenil Halogenados/metabolismo , Melatonina/metabolismo , Proteína X Associada a bcl-2/metabolismo , Chaperona BiP do Retículo Endoplasmático , Hepatócitos/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Apoptose , Proteínas Serina-Treonina Quinases/metabolismo , Estresse do Retículo Endoplasmático
5.
Plant Physiol Biochem ; 208: 108463, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38442625

RESUMO

Floral organ development is one of the most vital events in flowering plants and is closely related to ornamental properties. The proliferate flower (a new branch or flower occurring in the centre of a flower) in plants is an interesting type, while the specific molecular mechanism remains largely unknown. Osmanthus fragrans 'Tianxiang Taige' has two different flower morphologies: normal flower and proliferate flower. Phenotypic observation suggested that a normal flower was composed of calyx, petal, stamen and pistil (reduced to leaf-like carpel). While in proliferate flower, the leaf-like carpel continued to grow and was replaced by a new branch. Paraffin section indicated that the re-growth of leaf carpels might be the main reason for proliferate flower formation. Transcriptome sequencing of normal and proliferate flower was performed, and the expression levels of related genes were analysed. Among the differentially expressed genes, OfBFT-a and OfBFT-b had differential expression during the proliferate flower formation process. The expression patterns revealed that both OfBFT-a and OfBFT-b were highly accumulated in carpels, and were significantly downregulated during the proliferate flower development process. Subcellular localization indicated that OfBFT-a and OfBFT-b proteins were located in the nucleus. Functional studies in 'Tianxiang Taige' and Arabidopsis showed that OfBFT-a and OfBFT-b had important roles in floral organ development, especially the proliferate flower formation process by downregulating the accumulation of AG and SEP3 homologous genes. These results may shed new light on the study of proliferate flower formation and flower morphology breeding in flowering plants.


Assuntos
Arabidopsis , Magnoliopsida , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Melhoramento Vegetal , Plantas/genética , Arabidopsis/genética , Magnoliopsida/genética , Flores/genética
6.
Comput Biol Med ; 172: 108315, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38503093

RESUMO

The incidence of blinding eye diseases is highly correlated with changes in retinal morphology, and is clinically detected by segmenting retinal structures in fundus images. However, some existing methods have limitations in accurately segmenting thin vessels. In recent years, deep learning has made a splash in the medical image segmentation, but the lack of edge information representation due to repetitive convolution and pooling, limits the final segmentation accuracy. To this end, this paper proposes a pixel-level retinal vessel segmentation network with multiple-dimension attention and adaptive feature fusion. Here, a multiple dimension attention enhancement (MDAE) block is proposed to acquire more local edge information. Meanwhile, a deep guidance fusion (DGF) block and a cross-pooling semantic enhancement (CPSE) block are proposed simultaneously to acquire more global contexts. Further, the predictions of different decoding stages are learned and aggregated by an adaptive weight learner (AWL) unit to obtain the best weights for effective feature fusion. The experimental results on three public fundus image datasets show that proposed network could effectively enhance the segmentation performance on retinal blood vessels. In particular, the proposed method achieves AUC of 98.30%, 98.75%, and 98.71% on the DRIVE, CHASE_DB1, and STARE datasets, respectively, while the F1 score on all three datasets exceeded 83%. The source code of the proposed model is available at https://github.com/gegao310/VesselSeg-Pytorch-master.


Assuntos
Algoritmos , Retina , Retina/diagnóstico por imagem , Vasos Retinianos/diagnóstico por imagem , Fundo de Olho , Software , Processamento de Imagem Assistida por Computador/métodos
7.
Dig Dis Sci ; 69(4): 1263-1273, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38451429

RESUMO

BACKGROUND: A grim prognosis of pancreatic cancer (PCa) was attributed to the difficulty in early diagnosis of the disease. AIMS: Identifying novel biomarkers for early detection of PCa is thus urgent to improve the overall survival rates of patients. METHODS: The study was performed firstly by identification of candidate microRNAs (miRNAs) in formalin-fixed, paraffin-embedded tissues using microarray profiles, and followed by validation in a serum-based cohort study to assess clinical utility of the candidates. In the cohorts, a total of 1273 participants from four centers were retrospectively recruited as two cohorts including training and validation cohort. The collected serum specimens were analyzed by real-time polymerase chain reaction. RESULTS: We identified 27 miRNAs expressed differentially in PCa tissues as compared to the benign. Of which, the top-four was selected as a panel whose diagnostic efficacy was fully assessed in the serum specimens. The panel exhibited superior to CA19-9, CA125, CEA and CA242 in discriminating patients with early stage PCa from healthy controls or non-PCa including chronic pancreatitis as well as pancreatic cystic neoplasms, with the area under the curves (AUC) of 0.971 (95% CI 0.956-0.987) and 0.924 (95% CI 0.899-0.949), respectively. Moreover, the panel eliminated interference from other digestive tumors with a specificity of 90.2%. CONCLUSIONS: A panel of four serum miRNAs was developed showing remarkably discriminative ability of early stage PCa from either healthy controls or other pancreatic diseases, suggesting it may be developed as a novel, noninvasive approach for early screening of PCa in clinic.


Assuntos
MicroRNAs , Neoplasias Pancreáticas , Humanos , MicroRNAs/genética , Estudos Retrospectivos , Estudos de Coortes , Biomarcadores Tumorais , Detecção Precoce de Câncer , Neoplasias Pancreáticas/patologia
8.
J Vasc Surg ; 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38460766

RESUMO

OBJECTIVE: Selection criteria for carotid duplex ultrasonography screening (DUS) before coronary artery bypass grafting (CABG) is primarily based on limited observational analysis, and the risks associated with carotid artery stenosis (CAS) detected by this approach to preoperative DUS are uncertain. This study aimed to determine the association of carotid DUS with stroke and mortality among patients undergoing CABG. METHODS: Adult patients with coronary artery disease who underwent isolated CABG or CABG with concomitant valvular or congenital procedure were identified. CHA2DS2-VASc score was assessed before CABG, and patients were recorded as high risk if they had a score of 3 or higher. The primary outcomes were stroke and all-cause mortality. Secondary outcomes included ischemic stroke, non-ischemic stroke, transient ischemic attack, and cardiovascular mortality. RESULTS: Among 8958 patients who underwent CABG, 70.9% (n = 6347) received carotid DUS preoperatively (low-risk, 57.3%; high-risk, 42.7%). In the low-risk cohort, there was no significant difference in the risk of stroke (20.7 per 1000 patient-years for CAS vs 13.1 per 1000 patient-years for no CAS; adjusted hazard ratio [aHR], 1.14; 95% confidence interval [CI], 0.78-1.68) or mortality (20.5 per 1000 patient-years for CAS vs 16.8 per 1000 patient-years for no CAS; aHR, 1.33; 95% CI, 0.97-1.83) at 15 years. In the high-risk cohort, CAS was associated with significantly higher risks of stroke at 30 days (433.2 vs 279.5 per 1000 patient-years; aHR, 1.92; 95% CI, 1.00-3.70) and mortality at 15 years (38.4 vs 32.7 per 1000 patient-years; aHR, 1.25; 95% CI, 1.01-1.57) compared with no CAS. CONCLUSIONS: CAS did not impact the incidence of stroke or mortality in the low-risk cohort who underwent CABG. However, in the high-risk cohort, CAS was associated with a significant increase in the risks of 30-day stroke and 15-year mortality, indicating selective carotid DUS is necessarily recommended for these patients.

9.
Sheng Wu Gong Cheng Xue Bao ; 40(3): 799-811, 2024 Mar 25.
Artigo em Chinês | MEDLINE | ID: mdl-38545978

RESUMO

Pseudouridine is the most abundant modified nucleoside found in non-coding RNA and is widely used in biological and pharmaceutical fields. However, current methods for pseudouridine production suffer from drawbacks such as complex procedures, low efficiency and high costs. This study presents a novel enzymatic cascade reaction route in Escherichia coli, enabling the whole-cell catalytic synthesis of pseudouridine from uridine. Initially, a metabolic pathway was established through plasmid-mediated overexpression of endogenous pseudouridine-5-phosphase glycosidase, ribokinase, and ribonucleoside hydrolase, resulting in the accumulation of pseudouridine. Subsequently, highly active endogenous ribonucleoside hydrolase was screened to enhance uridine hydrolysis and provide more precursors for pseudouridine synthesis. Furthermore, modifications were made to the substrates and products transport pathways to increase the pseudouridine yield while avoiding the accumulation of by-product uridine. The resulting recombinant strain Ψ-7 catalyzed the conversion of 30 g/L uridine into 27.24 g/L pseudouridine in 24 h, achieving a conversion rate of 90.8% and a production efficiency of 1.135 g/(L·h). These values represent the highest reported yield and production efficiency achieved by enzymatic catalysis methods to date.


Assuntos
Escherichia coli , Pseudouridina , Pseudouridina/genética , Pseudouridina/química , Pseudouridina/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Uridina/genética , Uridina/química , Uridina/metabolismo , Catálise , Hidrolases/metabolismo
10.
Adv Mater ; : e2312153, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38444205

RESUMO

The presence of bacteria in tumor results in chemotherapeutic drug resistance and weakens the immune response in colorectal cancer. To overcome bacterium-induced chemotherapeutic drug resistance and potentiate antitumor immunity, herein a novel molecule Biotin-Lys(SA-Cip-OH)-Lys(SA-CPT)-Phe-Phe-Nap (Biotin-Cip-CPT-Nap) is rationally designed containing four functional motifs (i.e., a biotin motif for targeting, Phe-Phe(-Nap) motif for self-assembly, ciprofloxacin derivative (Cip-OH) motif for antibacterial effect, and camptothecin (CPT) motif for chemotherapy). Using the designed molecule, a novel strategy of intracellular enzymatic nanofiber formation and synergistic antibacterium-enhanced chemotherapy and immunotherapy is achieved. Under endocytosis mediated by highly expressed biotin receptor in colorectal cancer cell membrane and the catalysis of highly expressed carboxylesterase in the cytoplasm, this novel molecule can be transformed into Biotin-Nap, which self-assembled into nanofibers. Meanwhile, antibiotic Cip-OH and chemotherapeutic drug CPT are released, overcoming bacterium-induced drug resistance and enhancing the therapeutic efficacy of immunotherapy towards colorectal cancer. This work offers a feasible strategy for the design of novel multifunctional prodrugs to improve the efficiency of colorectal cancer treatment.

11.
J Cell Biol ; 223(5)2024 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-38358348

RESUMO

Loss-of-function mutations in VPS13C are linked to early-onset Parkinson's disease (PD). While VPS13C has been previously studied in non-neuronal cells, the neuronal role of VPS13C in disease-relevant human dopaminergic neurons has not been elucidated. Using live-cell microscopy, we investigated the role of VPS13C in regulating lysosomal dynamics and function in human iPSC-derived dopaminergic neurons. Loss of VPS13C in dopaminergic neurons disrupts lysosomal morphology and dynamics with increased inter-lysosomal contacts, leading to impaired lysosomal motility and cellular distribution, as well as defective lysosomal hydrolytic activity and acidification. We identified Rab10 as a phospho-dependent interactor of VPS13C on lysosomes and observed a decreased phospho-Rab10-mediated lysosomal stress response upon loss of VPS13C. These findings highlight an important role of VPS13C in regulating lysosomal homeostasis in human dopaminergic neurons and suggest that disruptions in Rab10-mediated lysosomal stress response contribute to disease pathogenesis in VPS13C-linked PD.


Assuntos
Neurônios Dopaminérgicos , Lisossomos , Proteínas rab de Ligação ao GTP , Humanos , Neurônios Dopaminérgicos/citologia , Homeostase , Hidrólise , Células-Tronco Pluripotentes Induzidas , Proteínas , Proteínas rab de Ligação ao GTP/genética
12.
Curr Med Chem ; 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38310398

RESUMO

Cancer immunotherapy has demonstrated remarkable success in the treatment of multiple advanced malignancies, especially approaches to target the immune checkpoint. Nonetheless, the limited response rate remains a barrier to broader application. Identifying other ways to extend the beneficiaries to a large extent is needed. Emerging evidence has shown that mitogen-activated protein kinase-interacting kinases (MNKs) could be regarded as a novel, attractive target for cancer immunotherapy that is closely correlated with cancer biology and therapies. A comprehensive understanding of the role and mechanism of MNKs in cancer will shed light on the discovery of novel therapeutic strategies for cancer treatment. In this review, we outlined the structure of MNKs, their function and expression, and how MNKs affect tumor progression and elucidated the evidence supporting MNKs as a new promising treatment modality in human cancers.

13.
Mol Cancer ; 23(1): 23, 2024 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-38263157

RESUMO

BACKGROUND: Colorectal cancer (CRC) is a major cause of cancer-related deaths worldwide, and chemoresistance is a major obstacle in its treatment. Despite advances in therapy, the molecular mechanism underlying chemoresistance in CRC is not fully understood. Recent studies have implicated the key roles of long noncoding RNAs (lncRNAs) in the regulation of CRC chemoresistance. METHODS: In this study, we investigated the role of the lncRNA LINC01852 in CRC chemoresistance. LINC01852 expression was evaluated in multiple CRC cohorts using quantitative reverse transcription PCR. We conducted in vitro and in vivo functional experiments using cell culture and mouse models. RNA pull-down, RNA immunoprecipitation, chromatin immunoprecipitation, and dual luciferase assays were used to investigate the molecular mechanism of LINC01852 in CRC. RESULTS: Our findings revealed that a lncRNA with tumor-inhibiting properties, LINC01852, was downregulated in CRC and inhibited cell proliferation and chemoresistance both in vitro and in vivo. Further mechanistic investigations revealed that LINC01852 increases TRIM72-mediated ubiquitination and degradation of SRSF5, inhibiting SRSF5-mediated alternative splicing of PKM and thereby decreasing the production of PKM2. Overexpression of LINC01852 induces a metabolic switch from aerobic glycolysis to oxidative phosphorylation, which attenuates the chemoresistance of CRC cells by inhibiting PKM2-mediated glycolysis. CONCLUSIONS: Our results demonstrate that LINC01852 plays an important role in repressing CRC malignancy and chemoresistance by regulating SRSF5-mediated alternative splicing of PKM, and that targeting the LINC01852/TRIM72/SRSF5/PKM2 signaling axis may represent a potential therapeutic strategy for CRC.


Assuntos
Neoplasias Colorretais , RNA Longo não Codificante , Animais , Camundongos , Humanos , Processamento Alternativo , Resistencia a Medicamentos Antineoplásicos , Carcinogênese , Transformação Celular Neoplásica , Imunoprecipitação da Cromatina
14.
Pathol Res Pract ; 253: 155065, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38171082

RESUMO

Gastric cancer (GC) is a rising global health issue, with increasing incidence and mortality rates. The pathogenesis of GC is highly complex and involves a combination of genetic and environmental factors. Therefore, identifying new genes and pathways that contribute to the development and progression of GC is essential for improving diagnosis and treatment outcomes. Long noncoding RNAs (lncRNAs) have recently emerged as a promising area of research in understanding the molecular mechanisms underlying various cancers, including GC. These RNA molecules are longer than 200 nucleotides and do not code proteins. Although initially considered "junk DNA", lncRNAs have been demonstrated to play significant roles in various biological processes, including cell proliferation, differentiation, and apoptosis, as well as in the pathogenesis of various cancers. In this study, we screened clinical specimens for a novel lncRNA, LINC00853, which showed high expression in GC tissues and promoted the proliferation, migration, and invasion of GC cells. Furthermore, in vivo experiments confirmed its ability to facilitate the growth and metastasis of GC. These results suggest that LINC00853 plays a crucial role in the development and progression of GC.


Assuntos
RNA Longo não Codificante , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/patologia , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Transformação Celular Neoplásica/genética , Proliferação de Células/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/genética , Movimento Celular/genética
15.
Lab Chip ; 24(3): 594-603, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38175166

RESUMO

Developing a fluidic platform that combines high-throughput with reconfigurability is essential for a wide range of cutting-edge applications, but achieving both capabilities simultaneously remains a significant challenge. Herein, we propose a novel and unique method for droplet manipulation via drawing surface charge graphics on electrode-free papers in a contactless way. We find that opposite charge graphics can be written and retained on the surface layer of porous insulating paper by a controlled charge depositing method. The retained charge graphics result in high-resolution patterning of electrostatic potential wells (EPWs) on the hydrophobic porous surface, allowing for digital and high-throughput droplet handling. Since the charge graphics can be written/projected dynamically and simultaneously in large areas, allowing for on-demand and real-time reconfiguration of EPWs, we are able to develop a charge-graphic fluidic platform with both high reconfigurability and high throughput. The advantages and application potential of the platform have been demonstrated in chemical detection and dynamically controllable fluidic networks.

16.
Microb Biotechnol ; 17(2): e14394, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38226955

RESUMO

Corn straw is an abundant and renewable alternative for microbial biopolymer production. In this paper, an engineered Sphingomonas sanxanigenens NXG-P916 capable of co-utilising glucose and xylose from corn straw total hydrolysate to produce xanthan gum was constructed. This strain was obtained by introducing the xanthan gum synthetic operon gum as a module into the genome of the constructed chassis strain NXdPE that could mass produce activated precursors of polysaccharide, and in which the transcriptional levels of gum genes were optimised by screening for a more appropriate promoter, P916 . As a result, strain NXG-P916 produced 9.48 ± 0.34 g of xanthan gum per kg of fermentation broth (g/kg) when glucose was used as a carbon source, which was 2.1 times improved over the original engineering strain NXdPE::gum. Furthermore, in batch fermentation, 12.72 ± 0.75 g/kg xanthan gum was produced from the corn straw total hydrolysate containing both glucose and xylose, and the producing xanthan gum showed an ultrahigh molecular weight (UHMW) of 6.04 × 107 Da, which was increased by 15.8 times. Therefore, the great potential of producing UHMW xanthan gum by Sphingomonas sanxanigenens was proved, and the chassis NXdPE has the prospect of becoming an attractive platform organism producing polysaccharides derived from biomass hydrolysates.


Assuntos
Glucose , Polissacarídeos Bacterianos , Sphingomonas , Xilose , Sphingomonas/genética , Zea mays , Peso Molecular
17.
J Mol Model ; 30(2): 26, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38191945

RESUMO

CONTEXT: The reaction between Na and HF is a typical harpooning reaction which is of great interest due to its significance in understanding the elementary chemical reaction kinetics. This work aims to investigate the detailed reaction mechanisms of sodium with hydrogen fluoride and the adsorption of HF on the resultant NaF as well as the (NaF)4 tetramer. The results suggest that the reaction between Na and HF leads to the formation of sodium fluoride salt NaF and hydrogen gas. Na interacts with HF to form a complex HF···Na, and then the approaching of F atom of HF to Na results in a transition state H···F···Na. Accompanied by the broken of H-F bond, the bond forms between F and Na atoms as NaF, then the product NaF is yielded due to the removal of H atom. The resultant NaF can further form (NaF)4 tetramer. The interaction of NaF with HF leads to the complex NaF···HF; the form I as well as II of (NaF)4 can interact with HF to produce two complexes (i.e., (NaF)4(I-1)···HF, (NaF)4(I-2)···HF, (NaF)4(II-1)···HF and (NaF)4(II-2)···HF), but the form III of (NaF)4 can interact with HF to produce only one complex (NaF)4(III)···HF. These complexes were explored in terms of noncovalent interaction (NCI) and quantum theory of atoms in molecules (QTAIM) analyses. NCI analyses confirm the existences of attractive interactions in the complexes HF···Na, NaF···HF, (NaF)4(I-1)···HF, (NaF)4(I-2)···HF, (NaF)4(II-1)···HF and (NaF)4(II-2)···HF, and (NaF)4(III)···HF. QTAIM analyses suggest that the F···Na interaction forms in the HF···Na complex while the F···H hydrogen bonds form in NaF···HF, (NaF)4(I-1)···HF, (NaF)4(I-2)···HF, (NaF)4(II-1)···HF and (NaF)4(II-2)···HF, and (NaF)4(III)···HF complexes. Natural bond orbital (NBO) analyses were also applied to analyze the intermolecular donor-acceptor orbital interactions in these complexes. These results would provide valuable insight into the chemical reaction of Na and HF and the adsorption interaction between sodium fluoride salt and HF. METHODS: The calculations were carried out at the M06-L/6-311++G(2d,2p) level of theory which were performed using the Gaussian16 program. Intrinsic reaction coordinate (IRC) calculations were carried out at the same level of theory to confirm that the obtained transition state was true. The molecular surface electrostatic potential (MSEP) was employed to understand how the complex forms. Quantum theory of atoms in molecules (QTAIM) and noncovalent interaction (NCI) analysis was used to know the topology parameters at bond critical points (BCPs) and intermolecular interactions in the complex and intermediate. The topology parameters and the BCP plots were obtained by the Multiwfn software.

18.
Biomater Sci ; 12(3): 763-775, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38164004

RESUMO

The immune system of astronauts might become weakened in the microgravity environment in space, and the dormant varicella-zoster virus (VZV) in the body might be reactivated, seriously affecting their work and safety. For working in orbit for the long term, there is currently no efficient and durable delivery system of general vaccines in a microgravity environment. Accordingly, based on the previous foundation, we designed, modified, and synthesized a biodegradable and biocompatible copolymer, polyethylene glycol-polysulfamethazine carbonate urethane (PEG-PSCU) that could be mainly adopted to fabricate a novel sustained-release microneedle (S-R MN) patch. Compared with conventional biodegradable microneedles, this S-R MN patch could not only efficiently encapsulate protein vaccines (varicella-zoster virus glycoprotein E, VZV gE) but also further prolong the release time of VZV gE in a simulated microgravity (SMG) environment. Eventually, we verified the activation of dendritic cells by VZV gE released from the S-R MN patch in an SMG environment and the positive bioeffect of activated dendritic cells on lymphocytes using an in vitro lymph node model. This study is of great significance for the exploration of long-term specific immune responses to the VZV in an SMG environment.


Assuntos
Vacinas , Ausência de Peso , Herpesvirus Humano 3 , Preparações de Ação Retardada , Antígenos Virais
19.
Adv Healthc Mater ; 13(8): e2303216, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38156501

RESUMO

Bacterial cellulose is an extracellular polysaccharide produced by microorganisms, offering advantages such as high water-holding capacity, flexibility, and biocompatibility. However, its lack of bactericidal activity hampers its wide application. Usnic acid, a secondary metabolite derived from lichens of the Usnea genus, is recognized for its antibacterial and anti-biofilm efficiency, coupled with anti-inflammatory properties. Its water insolubility presents challenges for wide utilization and stable release. Sanxan gel, a novel polysaccharide, exhibits exceptional freeze-thaw stability, suspension properties, and high elasticity, rendering it effective as a suspending agent to improve the bioavailability of water-insoluble drugs. In this study, a hydrogel membrane is designed by combining bacterial cellulose and usnic acid suspended in sanxan gel through a simple in situ microorganism fermentation. The obtained membranes demonstrate excellent ability for sustained drug release, strong eradication capability against tested bacteria in both in vitro and in vivo experiments, effective inhibition of biofilm formation, and excellent hemocompatibility and cytocompatibility. Additionally, the composite membranes promote wound healing with reduced inflammation and bacterial infection in a full-thickness wound infection model in mice. This study provides innovative insights and strategies for the development of functional dressings for infected wounds in future clinical applications.


Assuntos
Celulose , Hidrogéis , Animais , Camundongos , Bactérias , Antibacterianos , Água
20.
Eur J Clin Pharmacol ; 80(3): 409-415, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38158395

RESUMO

PURPOSE: 10 mg rivaroxaban is widely used in the Chinese mainland. This study aims to explore the association between 10 mg once daily rivaroxaban and all-cause mortality in patients with nonvalvular atrial fibrillation (NVAF). METHODS: This observational study enrolled 1131 NVAF patients at the cardiovascular department of the First Affiliated Hospital of Xi'an Jiaotong University. One-year outcomes included all-cause mortality and bleeding were recorded. Cox proportional hazards models and Kaplan-Meier analysis were utilized in the study. RESULTS: In total, 1131 patients (402 no anticoagulants, and 729 rivaroxaban) were included. Cox proportional hazard analysis demonstrated that low-dose rivaroxaban (10 mg, HR: 0.14, 95% CI:(0.07-0.28), P<0.001; 15 mg, HR: 0.20, 95% CI:(0.09-0.43), P<0.001; 20 mg, HR: 0.22, 95% CI:(0.05-0.96), P = 0.044) exhibited lower mortality risk compared to untreated patients. CONCLUSIONS: 10 mg once daily rivaroxaban may provide survival benefits for elderly patients with NVAF.


Assuntos
Fibrilação Atrial , Acidente Vascular Cerebral , Humanos , Idoso , Rivaroxabana/efeitos adversos , Acidente Vascular Cerebral/tratamento farmacológico , Estudos Retrospectivos , Anticoagulantes/efeitos adversos , Fibrilação Atrial/complicações , China , Dabigatrana/uso terapêutico , Piridonas/efeitos adversos
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