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1.
Chem Commun (Camb) ; 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39046327

RESUMO

Sulfoxides have emerged as pivotal constituents in modern carbohydrate chemistry. As anomeric leaving groups, sulfinyl moieties may occupy positions directly at the anomeric position or at a more remote site. This feature article is focused on the evolution and notable advancements of glycosyl sulfoxide donors in glycosylation reactions. Its objective is to elucidate the obstacles and prospects within this evolving research domain, with the aim of enhancing comprehension and progress in the field of carbohydrate chemistry.

2.
Acad Radiol ; 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39043516

RESUMO

RATIONALE AND OBJECTIVES: To investigate the diagnostic performance of water-specific T1 mapping for staging liver fibrosis in a non-alcoholic fatty liver disease (NAFLD) rabbit model, in comparison to Modified Look-Locker Inversion recovery (MOLLI) T1 mapping. MATERIALS AND METHODS: 60 rabbits were randomly divided into the control group (12 rabbits) and NAFLD model groups (eight rabbits per subgroup) corresponding to different durations of high-fat high cholesterol diet feeding. All rabbits underwent MRI examination including MOLLI T1 mapping and 3D multi-echo variable flip angle (VFAME- GRE) sequences were acquired before and 20 min after the administration of Gd- EOB-DTPA. Histological assessments were performed to evaluate steatosis, inflammation, ballooning, and fibrosis. Statistical analysis included the intraclass correlation coefficient, analysis of variance, spearman correlation, multiple linear regression, and receiver operating characteristic curve. RESULTS: A moderate correlation was observed between conventional native T1 and MRI-PDFF (r = -0.513, P < 0.001), as well as between conventional native T1 and liver steatosis grades (r = -0.319, P = 0.016). However, no significant correlation was found between the native wT1 and PDFF (r = 0.137, P = 0.314), or between the native wT1 and steatosis grades (r = 0.106, P = 0.435). In the multiple regression analysis, liver fibrosis, and hepatocellular ballooning were identified as independent factors influencing native wT1 in this study (R2 =0.545, P < 0.05), while steatosis was independently associated with conventional native T1 (R2 =0.321, P < 0.05). The AUC values for native T1, native wT1, HBP T1, and HBP wT1 were 0.549(0.410-0.682), 0.811(0.684-0.903), 0.775(0.644-0.876), and 0.752(0.619-0.858) for F1 or higher, 0.581(0.441-0.711), 0.828(0.704-0.916), 0.832(0.708-0.919), and 0.854(0.734-0.934) for F2 or higher, respectively. CONCLUSION: The native wT1 may provide a more reliable assessment of early liver fibrosis in the context of NAFLD compared to conventional native T1.

3.
Org Lett ; 26(28): 6053-6058, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-38985301

RESUMO

We have developed a highly effective glycosylation method that involves the activation of 2-(2-propylsulfinyl)benzyl 1,2-orthoester glycosides using triflic anhydride (Tf2O). Our research indicates that half of the glycosyl donor is activated through Tf2O via an interrupted Pummerer reaction mechanism, while the remaining portion is activated by triflic acid (TfOH) generated in situ. As a result, as little as 0.5 equiv of Tf2O is adequate for activating the orthoester glycoside donors. This glycosylation procedure offers several benefits, such as high efficiency, wide applicability, and the utilization of a recyclable leaving group.

4.
Nano Lett ; 24(28): 8752-8762, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38953881

RESUMO

Acute methicillin-resistant Staphylococcus aureus (MRSA) pneumonia is a common and serious lung infection with high morbidity and mortality rates. Due to the increasing antibiotic resistance, toxicity, and pathogenicity of MRSA, there is an urgent need to explore effective antibacterial strategies. In this study, we developed a dry powder inhalable formulation which is composed of porous microspheres prepared from poly(lactic-co-glycolic acid) (PLGA), internally loaded with indocyanine green (ICG)-modified, heat-resistant phages that we screened for their high efficacy against MRSA. This formulation can deliver therapeutic doses of ICG-modified active phages to the deep lung tissue infection sites, avoiding rapid clearance by alveolar macrophages. Combined with the synergistic treatment of phage therapy and photothermal therapy, the formulation demonstrates potent bactericidal effects in acute MRSA pneumonia. With its long-term stability at room temperature and inhalable characteristics, this formulation has the potential to be a promising drug for the clinical treatment of MRSA pneumonia.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Animais , Camundongos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Microesferas , Terapia Fototérmica , Pneumonia Estafilocócica/terapia , Terapia por Fagos/métodos , Verde de Indocianina/química , Verde de Indocianina/farmacologia , Verde de Indocianina/uso terapêutico , Verde de Indocianina/administração & dosagem , Antibacterianos/química , Antibacterianos/farmacologia , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Administração por Inalação , Humanos , Bacteriófagos/química
5.
Cancer Med ; 13(12): e7328, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38924332

RESUMO

BACKGROUND: Sarcopenia is highly prevalent among patients with colorectal cancer (CRC). Computed tomography (CT)-based assessment of low skeletal muscle index (SMI) is widely used for diagnosing sarcopenia. However, there are conflicting findings on the association between low SMI and overall survival (OS) in CRC patients. The objective of this study was to investigate whether CT-determined low SMI can serve as a valuable prognostic factor in CRC. METHODS: We collected data from patients with CRC who underwent radical surgery at our institution between June 2020 and November 2021. The SMI at the third lumbar vertebra was calculated using CT scans, and the cutoff values for defining low SMI were determined using receiver operating characteristic curves. Univariate and multivariate analyses were performed to assess the associations between clinical characteristics and postoperative major complications. RESULTS: A total of 464 patients were included in the study, 229 patients (46.7%) were classified as having low SMI. Patients with low SMI were older and had a lower body mass index (BMI), a higher neutrophil to lymphocyte ratio (NLR), and higher nutritional risk screening 2002 (NRS2002) scores compared to those with normal SMI. Furthermore, patients with sarcopenia had a higher rate of major complications (10.9% vs. 1.3%; p < 0.001) and longer length of stay (9.09 ± 4.86 days vs. 8.25 ± 3.12 days; p = 0.03). Low SMI and coronary heart disease were identified as independent risk factors for postoperative major complications. Moreover, CRC patients with low SMI had significantly worse OS. Furthermore, the combination of low SMI with older age or TNM stage II + III resulted in the worst OS in each subgroup analysis. CONCLUSIONS: CT-determined low SMI is associated with poor prognosis in patients with CRC, especially when combined with older age or advanced TNM stage.


Assuntos
Neoplasias Colorretais , Músculo Esquelético , Sarcopenia , Tomografia Computadorizada por Raios X , Humanos , Masculino , Feminino , Neoplasias Colorretais/cirurgia , Neoplasias Colorretais/patologia , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/complicações , Neoplasias Colorretais/diagnóstico por imagem , Sarcopenia/diagnóstico por imagem , Idoso , Tomografia Computadorizada por Raios X/métodos , Prognóstico , Pessoa de Meia-Idade , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/patologia , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Índice de Massa Corporal , Curva ROC
6.
Water Res ; 259: 121851, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38851110

RESUMO

Overuse of antibiotics has led to their existence in nitrogen-containing water. The impacts of antibiotics on bio-denitrification and the metabolic response of denitrifiers to antibiotics are unclear. We systematically analyzed the effect of ciprofloxacin (CIP) on bio-denitrification and found that 5 mg/L CIP greatly inhibited denitrification with a model denitrifier (Paracoccus denitrificans). Nitrate reduction decreased by 32.89 % and nitrous oxide emission increased by 75.53 %. The balance analysis of carbon and nitrogen metabolism during denitrification showed that CIP exposure blocked electron transfer and reduced the flow of substrate metabolism used for denitrification. Proteomics results showed that CIP exposure induced denitrifiers to use the pentose phosphate pathway more for substrate metabolism. This caused a substrate preference to generate NADPH to prevent cellular damage rather than NADH for denitrification. Notably, despite denitrifiers having antioxidant defenses, they could not completely prevent oxidative damage caused by CIP exposure. The effect of CIP exposure on denitrifiers after removal of extracellular polymeric substances (EPS) demonstrated that EPS around denitrifiers formed a barrier against CIP. Fluorescence and infrared spectroscopy revealed that the binding effect of proteins in EPS to CIP prevented damage. This study shows that denitrifiers resist antibiotic stress through different intracellular and extracellular defense strategies.


Assuntos
Antibacterianos , Ciprofloxacina , Desnitrificação , Ciprofloxacina/farmacologia , Antibacterianos/farmacologia , Paracoccus denitrificans/metabolismo
7.
Bioresour Technol ; 406: 130959, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38876286

RESUMO

Despite the increased research efforts aimed at understanding iron-based conductive materials (CMs) for facilitating chain elongation (CE) to produce medium chain fatty acids (MCFAs), the impact of these materials on microbial community functions and the adaptation mechanisms to their biotoxicity remain unclear. This study found that the supply of zero-valent iron (ZVI) and magnetite enhanced the MCFAs carbon-flow distribution by 26 % and 52 %, respectively. Metagenomic analysis revealed the upregulation of fatty acid metabolism, pyruvate metabolism and ABC transporters with ZVI and magnetite. The predominant functional microorganisms were Massilibacterium and Tidjanibacter with ZVI, and were Petrimonas and Candidatus_Microthrix with magnetite. Furthermore, it was demonstrated that CE microorganisms respond and adapt to the biotoxicity of iron-based CMs by adjusting Two-component system and Quorum sensing for the first time. In summary, this study provided a new deep-insight on the feedback mechanisms of CE microorganisms on iron-based CMs.


Assuntos
Ferro , Ferro/farmacologia , Ferro/metabolismo , Adaptação Fisiológica/efeitos dos fármacos , Ácidos Graxos/metabolismo , Bactérias/metabolismo , Bactérias/efeitos dos fármacos , Óxido Ferroso-Férrico/química , Percepção de Quorum/efeitos dos fármacos
8.
Bioresour Technol ; 406: 130958, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38876284

RESUMO

To address the environmental hazards posed by high-yield soybean dreg (SD), a high-value strategy is firstly proposed by synthesizing caproate through chain elongation (CE). Optimized conditions for lactate-rich broth as intermediate, utilizing 50 % inoculum ratio, 40 g/L substrate concentration, and pH 5, resulting in 2.05 g/L caproate from direct fermentation. Leveraging lactate-rich broth supplemented with ethanol, caproate was optimized to 2.76 g/L under a refined electron donor to acceptor of 2:1. Furthermore, incorporating 20 g/L biochar elevated caproate production to 3.05 g/L and significantly shortened the lag phase. Mechanistic insights revealed that biochar's surface-existed quinone and hydroquinone groups exhibit potent redox characteristics, thereby facilitating electron transfer. Moreover, biochar up-regulated the abundance of key genes involved in CE process (especially fatty acids biosynthesis pathway), also enriching Lysinibacillus and Pseudomonas as an unrecognized cooperation to CE. This study paves a way for sustainable development of SD by upgrading to caproate.


Assuntos
Carvão Vegetal , Glycine max , Ácido Láctico , Glycine max/metabolismo , Carvão Vegetal/química , Ácido Láctico/metabolismo , Fermentação
9.
Bioresour Technol ; 406: 131041, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38925404

RESUMO

To effectively treat actual ammonia-rich Chinese medicine residue (CMR) resource utilization wastewater, we optimized an anaerobic-microaerobic two-stage expanded granular sludge bed (EGSB) and moving bed sequencing batch reactor (MBSBR) combined process. By controlling dissolved oxygen (DO) levels, impressive removal efficiencies were achieved. Microaeration, contrasting with anaerobic conditions, bolstered dehydrogenase activity, enhanced electron transfer, and enriched the functional microorganism community. The increased relative abundance of Synergistetes and Proteobacteria facilitated hydrolytic acidification and fostered nitrogen and phosphorus removal. Furthermore, we examined the impact of DO concentration in MBSBR on pollutant removal and microbial metabolic activity, pinpointing 2.5 mg/L as the optimal DO concentration for superior removal performance and energy conservation.


Assuntos
Amônia , Reatores Biológicos , Oxigênio , Águas Residuárias , Águas Residuárias/química , Oxigênio/metabolismo , Purificação da Água/métodos , Biodegradação Ambiental , Esgotos , Poluentes Químicos da Água , Eliminação de Resíduos Líquidos/métodos , Fósforo , Medicamentos de Ervas Chinesas/farmacologia , Nitrogênio
10.
Front Immunol ; 15: 1376276, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38745658

RESUMO

Background: Hepatic Inflammatory Pseudotumor (IPT) is an infrequent condition often masquerading as a malignant tumor, resulting in misdiagnosis and unnecessary surgical resection. The emerging concept of IgG4-related diseases (IgG4-RD) has gained widespread recognition, encompassing entities like IgG4-related hepatic IPT. Clinically and radiologically, corticosteroids and immunosuppressive therapies have proven effective in managing this condition. Case Presentation: A 3-year-old Chinese boy presented to the clinic with an 11-month history of anemia, fever of unknown origin, and a tender hepatic mass. Blood examinations revealed chronic anemia (Hb: 6.4 g/L, MCV: 68.6 fl, MCH: 19.5 pg, reticulocytes: 1.7%) accompanied by an inflammatory reaction and an elevated serum IgG4 level (1542.2 mg/L). Abdominal contrast-enhanced computed tomography unveiled a 7.6 cm low-density mass in the right lateral lobe, while magnetic resonance imaging demonstrated slight hypointensity on T1-weighted images and slight hyperintensity on T2-weighted images, prompting suspicion of hepatic malignancy. A subsequent liver biopsy revealed a mass characterized by fibrous stroma and dense lymphoplasmacytic infiltration. Immunohistochemical analysis confirmed the presence of IgG4-positive plasma cells, leading to the diagnosis of IgG4-related hepatic IPT. Swift resolution occurred upon initiation of corticosteroid and mycophenolate mofetil therapies. Conclusion: This study underscores the diagnostic approach to hepatic IPT, utilizing histopathology, immunostaining, imaging, serology, organ involvement, and therapeutic response. Early histological examination plays a pivotal role in clinical guidance, averting misdiagnosis as a liver tumor and unnecessary surgical interventions.


Assuntos
Granuloma de Células Plasmáticas , Doença Relacionada a Imunoglobulina G4 , Imunoglobulina G , Humanos , Masculino , Granuloma de Células Plasmáticas/diagnóstico , Granuloma de Células Plasmáticas/imunologia , Granuloma de Células Plasmáticas/tratamento farmacológico , Pré-Escolar , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Doença Relacionada a Imunoglobulina G4/diagnóstico , Hepatopatias/diagnóstico , Hepatopatias/imunologia , Diagnóstico Diferencial , Fígado/patologia , Fígado/diagnóstico por imagem , Fígado/imunologia , Tomografia Computadorizada por Raios X , Biópsia , Imunossupressores/uso terapêutico
11.
Adv Sci (Weinh) ; 11(28): e2400790, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38741381

RESUMO

Heterotopic ossification (HO), the pathological formation of bone within soft tissues such as tendon and muscle, is a notable complication resulting from severe injury. While soft tissue injury is necessary for HO development, the specific molecular pathology responsible for trauma-induced HO remains a mystery. The previous study detected abnormal autophagy function in the early stages of tendon HO. Nevertheless, it remains to be determined whether autophagy governs the process of HO generation. Here, trauma-induced tendon HO model is used to investigate the relationship between autophagy and tendon calcification. In the early stages of tenotomy, it is observed that autophagic flux is significantly impaired and that blocking autophagic flux promoted the development of more rampant calcification. Moreover, Gt(ROSA)26sor transgenic mouse model experiments disclosed lysosomal acid dysfunction as chief reason behind impaired autophagic flux. Stimulating V-ATPase activity reinstated both lysosomal acid functioning and autophagic flux, thereby reversing tendon HO. This present study demonstrates that autophagy-lysosomal dysfunction triggers HO in the stages of tendon injury, with potential therapeutic targeting implications for HO.


Assuntos
Autofagia , Modelos Animais de Doenças , Lisossomos , Camundongos Transgênicos , Ossificação Heterotópica , Tendões , Ossificação Heterotópica/metabolismo , Ossificação Heterotópica/genética , Ossificação Heterotópica/patologia , Animais , Autofagia/fisiologia , Camundongos , Lisossomos/metabolismo , Tendões/metabolismo , Tendões/patologia , Tendões/fisiopatologia , Tenotomia/métodos , Masculino , Traumatismos dos Tendões/fisiopatologia , Traumatismos dos Tendões/metabolismo , Traumatismos dos Tendões/patologia , Camundongos Endogâmicos C57BL
12.
Sci Total Environ ; 930: 172515, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38642759

RESUMO

The disposal of Chinese medicinal herbal residues (CMHRs) derived from Chinese medicine extraction poses a significant environmental challenge. Aerobic composting presents a sustainable treatment method, yet optimizing nutrient conversion remains a critical concern. This study investigated the effect and mechanism of biochar addition on nitrogen and phosphorus transformation to enhance the efficacy and quality of compost products. The findings reveal that incorporating biochar considerably enhanced the process of nutrient conversion. Specifically, biochar addition promoted the retention of bioavailable organic nitrogen and reduced nitrogen loss by 28.1 %. Meanwhile, adding biochar inhibited the conversion of available phosphorus to non-available phosphorus while enhancing its conversion to moderately available phosphorus, thereby preserving phosphorus availability post-composting. Furthermore, the inclusion of biochar altered microbial community structure and fostered organic matter retention and humus formation, ultimately affecting the modification of nitrogen and phosphorus forms. Structural equation modeling revealed that microbial community had a more pronounced impact on bioavailable organic nitrogen, while humic acid exerted a more significant effect on phosphorus availability. This research provides a viable approach and foundation for regulating the levels of nitrogen and phosphorus nutrients during composting, serving as a valuable reference for the development of sustainable utilization technologies pertaining to CMHRs.


Assuntos
Carvão Vegetal , Compostagem , Substâncias Húmicas , Nitrogênio , Fósforo , Fósforo/análise , Carvão Vegetal/química , Nitrogênio/análise , Compostagem/métodos , Microbiologia do Solo , Medicamentos de Ervas Chinesas/química , Solo/química
14.
Cell Death Dis ; 15(4): 300, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38684648

RESUMO

The treatment of hepatocellular carcinoma (HCC) is particularly challenging due to the inherent tumoral heterogeneity and easy resistance towards chemotherapy and immunotherapy. Arsenic trioxide (ATO) has emerged as a cytotoxic agent effective for treating solid tumors, including advanced HCC. However, its effectiveness in HCC treatment remains limited, and the underlying mechanisms are still uncertain. Therefore, this study aimed to characterize the effects and mechanisms of ATO in HCC. By evaluating the susceptibilities of human and murine HCC cell lines to ATO treatment, we discovered that HCC cells exhibited a range of sensitivity to ATO treatment, highlighting their inherent heterogeneity. A gene signature comprising 265 genes was identified to distinguish ATO-sensitive from ATO-insensitive cells. According to this signature, HCC patients have also been classified and exhibited differential features of ATO response. Our results showed that ATO treatment induced reactive oxygen species (ROS) accumulation and the activation of multiple cell death modalities, including necroptosis and ferroptosis, in ATO-sensitive HCC cells. Meanwhile, elevated tumoral immunogenicity was also observed in ATO-sensitive HCC cells. Similar effects were not observed in ATO-insensitive cells. We reported that ATO treatment induced mitochondrial injury and mtDNA release into the cytoplasm in ATO-sensitive HCC tumors. This subsequently activated the cGAS-STING-IFN axis, facilitating CD8+ T cell infiltration and activation. However, we found that the IFN pathway also induced tumoral PD-L1 expression, potentially antagonizing ATO-mediated immune attack. Additional anti-PD1 therapy promoted the anti-tumor response of ATO in ATO-sensitive HCC tumors. In summary, our data indicate that heterogeneous ATO responses exist in HCC tumors, and ATO treatment significantly induces immunogenic cell death (ICD) and activates the tumor-derived mtDNA-STING-IFN axis. These findings may offer a new perspective on the clinical treatment of HCC and warrant further study.


Assuntos
Trióxido de Arsênio , Carcinoma Hepatocelular , Morte Celular Imunogênica , Neoplasias Hepáticas , Proteínas de Membrana , Nucleotidiltransferases , Trióxido de Arsênio/farmacologia , Trióxido de Arsênio/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Nucleotidiltransferases/metabolismo , Nucleotidiltransferases/genética , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Humanos , Animais , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Camundongos , Morte Celular Imunogênica/efeitos dos fármacos , Linhagem Celular Tumoral , Interferons/metabolismo , Transdução de Sinais/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Camundongos Endogâmicos C57BL
15.
Front Genet ; 15: 1390924, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38655052

RESUMO

Objective: The objective of this study was to pinpoint pathogenic genes and assess the mutagenic pathogenicity in two pediatric patients with hereditary spherocytosis. Methods: We utilized whole-exome sequencing (WES) for individual analysis (case 1) and family-based trio analysis (case 2). The significance of the intronic mutation was validated through a Minigene splicing assay and supported by subsequent in vitro experiments. Results: Both probands received a diagnosis of hereditary spherocytosis. WES identified a novel ANK1 c.1504-9G>A mutation in both patients, causing the retention of seven nucleotides at the 5' end of intron 13, as substantiated by the Minigene assay. This variant results in a premature stop codon and the production of a truncated protein. In vitro studies indicated a reduced expression of the ANK1 gene. Conclusion: The novel ANK1 c.1504-9G>A variant is established as the causative factor for hereditary spherocytosis, with the c.1504-9G site functioning as a splicing receptor.

16.
Water Res ; 254: 121417, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38461597

RESUMO

Single-atom catalysts (SACs) have emerged as competitive candidates for Fenton-like oxidation of micro-pollutants in water. However, the impact of metal insertion on the intrinsic catalytic activity of carrier materials has been commonly overlooked, and the environmental risk due to metal leaching still requires attention. In contrast to previous reports, where metal sites were conventionally considered as catalytic centers, our study investigates, for the first time, the crucial catalytic role of the carbon carrier modulated through hetero-single-atom dispersion and the regulation of Fenton-like oxidation pathways. The inherent differences in electronic properties between Fe and Co can effectively trigger long-range electron rearrangement in the sp2-carbon-conjugated structure, creating more electron-rich regions for peroxymonosulfate (PMS) complexation and initiating the electron transfer process (ETP) for pollutant degradation, which imparts the synthesized catalyst (FeCo-NCB) with exceptional catalytic efficiency despite its relatively low metal content. Moreover, the FeCo-NCB/PMS system exhibits enduring decontamination efficiency in complex water matrices, satisfactory catalytic stability, and low metal leaching, signifying promising practical applications. More impressively, the spatial relationship between metal sites and electron density clouds is revealed to determine whether high-valent metal-oxo species (HVMO) are involved during the decomposition of surface complexes. Unlike single-type single-atom dispersion, where metal sites are situated within electron-rich regions, hetero-single-atom dispersion can cause the deviation of electron density clouds from the metal sites, thus hindering the in-situ oxidation of metal within the complexes and minimizing the contribution of HVMO. These findings provide new insights into the development of carbon-based SACs and advance the understanding of nonradical mechanisms underpinning Fenton-like treatments.


Assuntos
Carbono , Poluentes Ambientais , Peróxidos , Oxirredução , Transporte de Elétrons , Eletrônica , Água
17.
ISA Trans ; 148: 140-155, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38453581

RESUMO

The existing impulsive consensus algorithms for second-order Lipschitz nonlinear multi-agent systems require to apply the impulsive control to both position and velocity vectors at the same time. Such a requirement cannot be met in most of the real-world applications. To overcome the limitations of these impulsive algorithms, two kinds of new second-order impulsive consensus algorithms using only velocity regulation are proposed. Through developing a weighted discontinuous Lyapunov function-based approach that is able to leverage the spectral property of Laplacian matrix, impulse-dwell-time-dependent sufficient conditions for solving second-order impulsive consensus are derived in the form of linear matrix inequalities. Further, it is shown that if the impulsively controlled velocity subsystems are globally exponentially stable, the impulsive static consensus algorithm is able to ensure that all agents tend to an agreed position. Based on the consensus conditions, two convex optimization problems are formulated, by which the impulsive gain matrices for ensuring a prescribed exponential convergence rate can be designed. Finally, the effectiveness of the proposed distributed impulsive consensus algorithms is certified through numerical simulations.

18.
Nat Biomed Eng ; 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38491329

RESUMO

Dental calculi can cause gingival bleeding and periodontitis, yet the mechanism underlying the formation of such mineral build-ups, and in particular the role of the local microenvironment, are unclear. Here we show that the formation of dental calculi involves bacteria in local mature biofilms converting the DNA in neutrophil extracellular traps (NETs) from being degradable by the enzyme DNase I to being degradation resistant, promoting the nucleation and growth of apatite. DNase I inhibited NET-induced mineralization in vitro and ex vivo, yet plasma DNases were ineffective at inhibiting ectopic mineralization in the oral cavity in rodents. The topical application of the DNA-intercalating agent chloroquine in rodents fed with a dental calculogenic diet reverted NET DNA to its degradable form, inhibiting the formation of calculi. Our findings may motivate therapeutic strategies for the reduction of the prevalence of the deposition of bacteria-driven calculi in the oral cavity.

19.
Quant Imaging Med Surg ; 14(2): 1591-1601, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38415124

RESUMO

Background: Gadolinium ethoxybenzyl-diethylenetriaminepentaacetic acid (Gd-EOB-DTPA) has shown potential in reflecting the hepatic function alterations in nonalcoholic steatohepatitis (NASH). The purpose of this study was to evaluate whether Gd-EOB-DTPA combined with water-specific T1 (wT1) mapping can be used to detect liver inflammation in the early-stage of NASH in rats. Methods: In this study, 54 rats with methionine- and choline-deficient (MCD) diet-induced NASH and 10 normal control rats were examined. A multiecho variable flip angle gradient echo (VFA-GRE) sequence was performed and repeated 40 times after the injection of Gd-EOB-DTPA. The wT1 of the liver and the reduction rate of wT1 (rrT1) were calculated. All rats were histologically evaluated and grouped according to the NASH Clinical Research Network scoring system. Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to detect the expression of Gd-EOB-DTPA transport genes. Analysis of variance and least significant difference tests were used for multiple comparisons of quantitative results between all groups. Multiple regression analysis was applied to identify variables associated with precontrast wT1 (wT1pre), and receiver operating characteristic (ROC) analysis was performed to assess the diagnostic performance. Results: The rats were grouped according to inflammatory stage (G0 =4, G1 =15, G2 =12, G3 =23) and fibrosis stage (F0 =26, F1 =19, F2 =9). After the infusion of Gd-EOB-DTPA, the rrT1 showed significant differences between the control and NASH groups (P<0.05) but no difference between the different inflammation and fibrosis groups at any time points. The areas under curve (AUCs) of rrT1 at 10, 20, and 30 minutes were only 0.53, 0.58, and 0.61, respectively, for differentiating between low inflammation grade (G0 + G1) and high inflammation grade (G2 + G3). The MRI findings were verified by qRT-PCR examination, in which the Gd-EOB-DTPA transporter expressions showed no significant differences between any inflammation groups. Conclusions: The wT1 mapping quantitative method combined with Gd-EOB-DTPA was not capable of discerning the inflammation grade in a rat model of early-stage NASH.

20.
Adv Mater ; 36(16): e2311659, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38175183

RESUMO

Enamel repair is crucial for restoring tooth function and halting dental caries. However, contemporary research often overlooks the retention of organic residues within the repair layer, which hinders the growth of dense crystals and compromises the properties of the repaired enamel. During the maturation of natural enamel, the organic matrix undergoes enzymatic processing to facilitate further crystal growth, resulting in a highly mineralized tissue. Inspired by this process, a biomimetic self-maturation mineralization system is developed, comprising ribonucleic acid-stabilized amorphous calcium phosphate (RNA-ACP) and ribonuclease (RNase). The RNA-ACP induces initial mineralization in the form of epitaxial crystal growth, while the RNase present in saliva automatically triggers a biomimetic self-maturation process. The mechanistic study further indicates that RNA degradation prompts conformational rearrangement of the RNA-ACP, effectively excluding the organic matter introduced earlier. This exclusion process promotes lateral crystal growth, resulting in the generation of denser enamel-like apatite crystals that are devoid of organic residues. This strategy of eliminating organic residues from enamel crystals enhances the mechanical and physiochemical properties of the repaired enamel. The present study introduces a conceptual biomimetic mineralization strategy for effective enamel repair in clinical practice and offers potential insights into the mechanisms of biomineral formation.


Assuntos
Biomimética , Fosfatos de Cálcio , Cárie Dentária , Humanos , RNA , Ribonucleases , Esmalte Dentário
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