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1.
Environ Microbiol ; 26(2): e16560, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38234207

RESUMO

Some bacteria can degrade organic micropollutants (OMPs) as primary carbon sources. Due to typically low OMP concentrations, these bacteria may benefit from supplemental assimilation of natural substrates present in the pool of dissolved organic matter (DOM). The biodegradability of such auxiliary substrates and the impacts on OMP removal are tightly linked to biotransformation pathways. Here, we aimed to elucidate the biodegradability and effect of different DOM constituents for the carbofuran degrader Novosphingobium sp. KN65.2, using a novel approach that combines pathway prediction, laboratory experiments, and fluorescence spectroscopy. Pathway prediction suggested that ring hydroxylation reactions catalysed by Rieske-type dioxygenases and flavin-dependent monooxygenases determine the transformability of the 11 aromatic compounds used as model DOM constituents. Our approach further identified two groups with distinct transformation mechanisms amongst the four growth-supporting compounds selected for mixed substrate biodegradation experiments with the pesticide carbofuran (Group 1: 4-hydroxybenzoic acid, 4-hydroxybenzaldehyde; Group 2: p-coumaric acid, ferulic acid). Carbofuran biodegradation kinetics were stable in the presence of both Group 1 and Group 2 auxiliary substrates. However, Group 2 substrates would be preferable for bioremediation processes, as they showed constant biodegradation kinetics under different experimental conditions (pre-growing KN65.2 on carbofuran vs. DOM constituent). Furthermore, Group 2 substrates were utilisable by KN65.2 in the presence of a competitor (Pseudomonas fluorescens sp. P17). Our study thus presents a simple and cost-efficient approach that reveals mechanistic insights into OMP-DOM biodegradation.


Assuntos
Carbofurano , Sphingomonadaceae , Biodegradação Ambiental , Carbofurano/metabolismo , Espectrometria de Fluorescência , Carbono/metabolismo , Compostos Orgânicos , Sphingomonadaceae/metabolismo
2.
Environ Sci Technol ; 58(8): 3919-3930, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38353611

RESUMO

The microorganisms present in kindergartens are extremely important for children's health during their three-year preschool education. To assess the risk of outdoor dust in kindergartens, the antibiotic resistome and potential pathogens were investigated in dust samples collected from 59 kindergartens in Xiamen, southeast China in both the winter and summer. Both high-throughput quantitative PCR and metagenome analysis revealed a higher richness and abundance of antibiotic resistance genes (ARGs) in winter (P < 0.05). Besides, the bloom of ARGs and potential pathogens was evident in the urban kindergartens. The co-occurrence patterns among ARGs, mobile genetic elements (MGEs), and potential pathogens suggested some bacterial pathogens were potential hosts of ARGs and MGEs. We found a large number of high-risk ARGs in the dust; the richness and abundance of high-risk ARGs were higher in winter and urban kindergartens compared to in summer and peri-urban kindergartens, respectively. The results of the co-occurrence patterns and high-risk ARGs jointly reveal that urbanization will significantly increase the threat of urban dust to human beings and their risks will be higher in winter. This study unveils the close association between ARGs/mobile ARGs and potential pathogens and emphasizes that we should pay more attention to the health risks induced by their combination.


Assuntos
Bactérias , Genes Bacterianos , Criança , Humanos , Resistência Microbiana a Medicamentos/genética , Bactérias/genética , China , Urbanização , Antibacterianos/farmacologia
3.
Artigo em Inglês | MEDLINE | ID: mdl-36404720

RESUMO

BACKGROUND: The regulatory network of competing endogenous RNAs (ceRNAs) affects tumorigenesis. In this study, we aimed to investigate the mechanism by which long non-coding RNA (lncRNA) HOXA-AS2 promotes prostate cancer (PCa) progression. METHODS: The expression levels of HOXA-AS2, miR-885-5p, and KDM5B in PCa tissues and cell lines were evaluated by qRT-PCR or western blotting. CCK-8 assay, caspase-3 activity assay, flow cytometry, and scratch test revealed changes in cell proliferation, caspase-3 activity, apoptosis, and migration, respectively. Luciferase and radioimmunoprecipitation assays were used to evaluate the correlation among HOXA-AS2, miR-885-5p, and KDM5B expression profiles. RESULTS: HOXA-AS2 expression level was elevated in PCa tissues and cells. Silencing of HOXA-AS2 suppressed proliferation and migration and facilitated apoptosis in PCa cells. HOXA-AS2 competitively adsorbed miR-885-5p, thereby blocking the effect of HOXA-AS2 knockdown by the miR-885-5p inhibitor in PCa cells. Moreover, KDM5B, a target of miR-885-5p, neutralized the function of miR-885-5p in PCa cells. CONCLUSIONS: This study revealed a potential ceRNA regulatory pathway in which HOXA-AS2 affects KDM5B expression levels by sponging miR-885-5p to promote PCa development and progression.

4.
World J Surg Oncol ; 19(1): 241, 2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34389000

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most common malignancies in the world, and due to its complex pathogenic factors, its prognosis is poor. N6-methyladenosine (m6A) RNA methylation plays an important role in the tumorigenesis, progression, and prognosis of many tumors. The m6A RNA methylation regulator small nuclear ribonucleoprotein polypeptide C (SNRPC), which encodes one of the specific protein components of the U1 small nuclear ribonucleoprotein (snRNP) particle, has been proven to be related to the prognosis of patients with HCC. However, the effect of SNRPC on the tumor microenvironment and immunotherapy in HCC remains unclear. CASE PRESENTATION: The HCC RNA-seq profiles in The Cancer Genome Atlas (TCGA) and International Cancer Genome Consortium (ICGC) databases, including 421 LIHC and 440 LIRI-JP samples, respectively, were used in this study. Both the expression of SNRPC in HCC was upregulated in the TCGA and ICGC databases compared to normal tissues. Next, the expression of SNRPC was validated as a risk factor for prognosis by Kaplan-Meier analysis and employed to establish a nomogram with T pathologic stage. By gene set variation (GSVA) analysis and gene set enrichment (GSEA) analysis, we found that SNRPC was mainly related to protein metabolism and the immune process. Furthermore, the estimation of stromal and immune cells in malignant tumor tissues using expression (ESTIMATE), microenvironment cell population counter (MCP-counter), and single sample GSEA (ssGSEA) algorithms revealed that the high-SNRPC group had a lower stromal score, lower abundance of endothelial cells and fibroblasts, and lower immune infiltration. Ultimately, a tumor immune dysfunction and exclusion (TIDE) analysis revealed that patients in the low-SNRPC group may be more sensitive to immune checkpoint inhibitor therapy. CONCLUSION: SNRPC could serve as a promising prognostic and immunotherapeutic marker in HCC and might contribute to new directions and strategies for HCC treatment.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Adenosina/análogos & derivados , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/terapia , Células Endoteliais , Regulação Neoplásica da Expressão Gênica , Humanos , Imunoterapia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/terapia , Metilação , Prognóstico , RNA/genética , Microambiente Tumoral
6.
Environ Sci Technol ; 53(15): 8533-8542, 2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-31269402

RESUMO

Global paddy soil is the primary source of methane, a potent greenhouse gas. It is therefore highly important to understand the carbon cycling in paddy soil. Microbial reduction of iron, which is widely found in paddy soil, is likely coupled with the oxidation of dissolved organic matter (DOM) and suppresses methanogenesis. However, little is known about the biotransformation of small molecular DOM accumulated under flooded conditions and the effect of iron reduction on the biotransformation pathway. Here, we carried out anaerobic incubation experiments using field-collected samples amended with ferrihydrite and different short-chain fatty acids. Our results showed that less than 20% of short-chain fatty acids were mineralized and released to the atmosphere. Using Fourier transform ion cyclotron resonance mass spectrometry, we further found that a large number of recalcitrant molecules were produced during microbial consumption of these short-chain fatty acids. Moreover, the biotransformation efficiency of short-chain fatty acids decreased with the increasing length of carbon chains. Ferrihydrite addition promoted microbial assimilation of short-chain fatty acids as well as enhanced the activation and biotransformation of indigenous stable carbon in the soil replenished with formate. This study demonstrates the significance of ferrihydrite in the biotransformation of labile DOM and promotes a more comprehensive understanding of the coupling of iron reduction and carbon cycling in paddy soils.


Assuntos
Oryza , Solo , Carbono , Ciclo do Carbono , Ferro , Metano , Microbiologia do Solo
7.
Med Sci Monit ; 25: 6504-6511, 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31467263

RESUMO

BACKGROUND Lung cancer with intracranial metastasis requires concurrent treatment of the primary lung tumor and the secondary brain tumor. This study aimed to investigate the short-term clinical efficacy of concurrent bronchial artery and posterior inferior cerebellar artery microcatheter interventional chemotherapy for the treatment of adenocarcinoma of the lung with solitary cerebellar metastasis. MATERIAL AND METHODS Seventeen patients with adenocarcinoma of the lung with solitary cerebellar metastasis received concurrent microcatheter interventional chemotherapy via the bronchial artery and posterior inferior cerebellar artery. Two cycles of treatment with teniposide (VM-26), carmustine (BCNU), carboplatin (CBP), and pirarubicin (THP) were performed every four weeks. RESULTS Four patients (23.53%) achieved a complete response (CR), five patients (29.41%) achieved a partial response (PR), seven patients (41.18%) had stable disease (SD), and only one patient (5.88%) developed progressive disease (PD). The objective response rate (ORR) and disease control rate (DCR) were 52.94% (9/17) and 94.12% (16/17), respectively. Four patients (11.76%) developed grade 1/2 chemotherapy toxicity, which included three cases (8.82%) of gastrointestinal toxicity and one case (2.84%) of granulocytopenia, but no grade 3/4 toxicity was found. During microcatheter interventional chemotherapy, three patients (8.82%) developed intracranial complications, including two cases (5.88%) of cerebrovascular spasm and one case (2.94%) of cerebral edema. CONCLUSIONS In 17 patients with adenocarcinoma of the lung with solitary cerebellar metastasis, concurrent microcatheter interventional chemotherapy via the bronchial artery and posterior inferior cerebellar artery was safe and showed short-term efficacy.


Assuntos
Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/cirurgia , Neoplasias Encefálicas/secundário , Artérias Brônquicas/cirurgia , Catéteres , Artérias Cerebrais/cirurgia , Adenocarcinoma de Pulmão/diagnóstico por imagem , Adulto , Idoso , Neoplasias Encefálicas/diagnóstico por imagem , Artérias Brônquicas/diagnóstico por imagem , Artérias Brônquicas/patologia , Artérias Cerebrais/diagnóstico por imagem , Artérias Cerebrais/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
8.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 36(12): 1183-1186, 2019 Dec 10.
Artigo em Zh | MEDLINE | ID: mdl-31813143

RESUMO

OBJECTIVE: To identify the type and origin of ATP7B gene mutation in a family affected with Wilson disease by combined use of multiple methods. METHODS: Peripheral blood samples were collected from the proband, her parents and her brother. Sanger sequencing were used to detect point mutation and small deletion/insertion of the 21 exons and flanking sequences of the ATP7B gene in all family members. Array-based comparative genomic hybridization (aCGH) was performed to identify copy number variations (CNVs) of the ATP7B gene in the proband. The result was validated by quantitative PCR (qPCR) in other 3 members. RESULTS: Sanger sequencing indicated that the proband carried a heterozygous variation c.2668G>A (p.V890M) derived from her mother. In addition, 5 common SNPs were detected in her mother, three of which were also identified in her father and brother. The 5 SNPs in the proband were of the wide type. aCGH analysis demonstrated that the proband was heterozygous for a 4 kb deletion, which encompassed exons 2 and 3 of the ATP7B gene and 2 SNPs. qPCR showed that the copy number in her father and brother was about half of the control, indicating heterozygous loss of exons 2 and 3. CONCLUSION: The combined Sanger sequencing, array CGH and qPCR has identified a novel CNV involving the ATP7B gene. The strategy can improve the diagnostic rate for hereditary or rare diseases.


Assuntos
Hibridização Genômica Comparativa , ATPases Transportadoras de Cobre/genética , Variações do Número de Cópias de DNA , Degeneração Hepatolenticular/genética , Análise Mutacional de DNA , Feminino , Heterozigoto , Humanos , Masculino , Mutação , Reação em Cadeia da Polimerase
9.
Zhongguo Yi Liao Qi Xie Za Zhi ; 42(6): 428-430, 2018 Nov 30.
Artigo em Zh | MEDLINE | ID: mdl-30560622

RESUMO

A new concept and solution of architecture of the intelligent POCT network, based on Internet of Things and intelligent POCT devices, is proposed. This network's topology structure and components with basic requirements are introduced. Through the experience of clinical application scenario, the main characteristics of the network and superiority over traditional POCT device have been analyzed.


Assuntos
Internet , Sistemas Automatizados de Assistência Junto ao Leito
10.
J Theor Biol ; 406: 42-51, 2016 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-27338302

RESUMO

Pancreatic cancer is one of the most deadly types of cancer since it typically spreads rapidly and can seldom be detected in its early stage. Pancreatic cancer therapy is thus a challenging task, and appropriate prognosis or assessment for pancreatic cancer therapy is of critical importance. In this work, based on available clinical data in Niu et al. (2013) we develop a mathematical prognosis model that can predict the overall survival of pancreatic cancer patients who receive immunotherapy. The mathematical model incorporates pancreatic cancer cells, pancreatic stellate cells, three major classes of immune effector cells CD8+ T cells, natural killer cells, helper T cells, and two major classes of cytokines interleukin-2 (IL-2) and interferon-γ (IFN-γ). The proposed model describes the dynamic interaction between tumor and immune cells. In order for the model to be able to generate appropriate prognostic results for disease progression, the distribution and stability properties of equilibria in the mathematical model are computed and analysed in absence of treatments. In addition, numerical simulations for disease progression with or without treatments are performed. It turns out that the median overall survival associated with CIK immunotherapy is prolonged from 7 to 13months compared with the survival without treatment, this is consistent with the clinical data observed in Niu et al. (2013). The validity of the proposed mathematical prognosis model is thus verified. Our study confirms that immunotherapy offers a better prognosis for pancreatic cancer patients. As a direct extension of this work, various new therapy methods that are under exploration and clinical trials could be assessed or evaluated using the newly developed mathematical prognosis model.


Assuntos
Imunoterapia , Modelos Biológicos , Neoplasias Pancreáticas/imunologia , Neoplasias Pancreáticas/terapia , Linfócitos T CD8-Positivos/imunologia , Simulação por Computador , Citotoxicidade Imunológica , Humanos , Neoplasias Pancreáticas/patologia , Prognóstico
11.
Soft Matter ; 11(43): 8479-83, 2015 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-26364811

RESUMO

The controlled dissolution of microdroplets on a supporting substrate is an effective approach that can be used to tune the assembled microstructure of basic units suspended within the droplet. In this work, we studied the self-assembly of two-dimensional graphene oxide (GO) nanosheets driven by the dissolution of a microdroplet situated at the interface between a solid substrate and the surrounding liquid phase. We found that although uniform microstructures form at the liquid-liquid interface of the droplets, the contact between the droplet and the substrate can give rise to a variety of different morphologies near the base of the droplet. In particular, pinning effects at the boundary of the dissolving droplet on the substrate lead to non-spherical GO assemblies. The results in this work demonstrate the possibility that tailored three-dimensional architectures of nanosheets assembled in a dissolving droplet may be achieved through control of the wetting properties of the droplet on the supporting substrate.

12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(7): 1926-32, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26717754

RESUMO

The behavior of pesticide in soil is influenced by dissolved organic matter (DOM) through competition adsorption, adsorption, solubilization, accelerated degradation, and so on. Thus DOM and its components play an important role in the environmental risk in the soil ecosystem and groundwater environment. Currently, most studies focused on the short-term effect of high concentration of DOM on the pesticide residues. However, soil DOM is mainly at low level. Therefore, there is of some practical significance to probe into the environmental behavior of soil pesticides under natural level of DOM. Thus a site investigation was conducted in the farmland with long-term application history of pesticide. By using the three dimensional excitation-emission fluorescence matrix (3D-EEM) technology, together with the fluorescence regional integration (FRI) quantitative method, the long-term effects of pesticide residues under low concentration of natural DOM were analyzed. Results showed that: (1) The long-term effects of the natural DOM components on the environment behavior of most soil organochlorine pesticides were not significant except for a few pesticides such as y-HCH, p, p'-DDE, etc. (2) The influencing effects of DOM components on different type of pesticides were varied. Among which, the content of tyrosine component showed a significantly negative correlation (p < 0.05) with the concentration of y-HCH and p, p'-DDE. There were significant positive correlations (p < 0.05) between the byproducts of microbial degradation in DOM components and the concentration of heptachlor. There were also a significant positive correlation (p < 0.05) between the content of active humus component of humic acid in the DOM and the concentration of heptachlor epoxide. These results suggested that the distribution of different types of pesticides residue in the soil was influenced by different components at different levels of significance. (3) The humification degree of soil organic matter showed minor effect of DOM on the pesticide residues in the soil. In this study, 3D-EEM and FRI technology were firstly coupled in use for studying the influence of different components of DOM in soil on the environmental behavior of pesticides, which provides a new idea for the research on the mechanism of pesticides transportation and transformation in soil and groundwater environment.


Assuntos
Resíduos de Praguicidas/análise , Poluentes do Solo/análise , Solo/química , Espectrometria de Fluorescência , Adsorção , Ecossistema , Fluorescência , Água Subterrânea , Substâncias Húmicas
14.
Front Endocrinol (Lausanne) ; 15: 1372553, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38501105

RESUMO

Driven by the intricacy of the illness and the need for individualized treatments, targeted therapy and biomarker research in thyroid cancer represent an important frontier in oncology. The variety of genetic changes associated with thyroid cancer demand more investigation to elucidate molecular details. This research is clinically significant since it can be used to develop customized treatment plans. A more focused approach is provided by targeted therapies, which target certain molecular targets such as mutant BRAF or RET proteins. This strategy minimizes collateral harm to healthy tissues and may also reduce adverse effects. Simultaneously, patient categorization based on molecular profiles is made possible by biomarker exploration, which allows for customized therapy regimens and maximizes therapeutic results. The benefits of targeted therapy and biomarker research go beyond their immediate clinical impact to encompass the whole cancer landscape. Comprehending the genetic underpinnings of thyroid cancer facilitates the creation of novel treatments that specifically target aberrant molecules. This advances the treatment of thyroid cancer and advances precision medicine, paving the way for the treatment of other cancers. Taken simply, more study on thyroid cancer is promising for better patient care. The concepts discovered during this investigation have the potential to completely transform the way that care is provided, bringing in a new era of personalized, precision medicine. This paradigm shift could improve the prognosis and quality of life for individuals with thyroid cancer and act as an inspiration for advances in other cancer types.


Assuntos
Qualidade de Vida , Neoplasias da Glândula Tireoide , Humanos , Neoplasias da Glândula Tireoide/tratamento farmacológico , Neoplasias da Glândula Tireoide/genética , Prognóstico , Medicina de Precisão , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo
15.
Sci Rep ; 14(1): 8694, 2024 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622149

RESUMO

We aimed to investigate the expression and clinic significance of Rac GTPase Activating Protein 1 (RACGAP1) in human lung adenocarcinoma (LUAD). Online database analysis revealed a significant increase in RACGAP1 mRNA expression among 26 types of tumor tissues, including LUAD tissues. Online database and tissue microarray analyses indicated that RACGAP1 expression was significantly upregulated in LUAD tissues. Genetic variation analysis identified four different genetic variations of RACGAPs in LUAD. Moreover, online database analysis showed that RACGAP1 upregulation was correlated with shorter survival in patients with LUAD. After silencing RACGAP1 expression in A549 cells using siRNA and assessing its protein levels via Western blotting, we found that RACGAP1 knockdown inhibited cell growth and induced apoptosis determined using the Cell Counting Kit-8 assay, colony formation assay, and flow cytometry. Mechanistically, western blot analysis indicated that Bax expression increased, whereas Bcl-2 expression decreased. Moreover, RACGAP1 knockdown attenuated PI3K/AKT pathway activation in lung cancer cells. Taken together, our findings showed that RACGAP1 was overexpressed in LUAD tissues and played an important role in lung cancer by increasing cell growth through the PI3K/AKT signaling pathway. This study suggests recommends evaluating RACGAP1 in clinical settings as a novel biomarker and potential therapeutic target for lung cancer.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/patologia , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais , Adenocarcinoma de Pulmão/patologia , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Linhagem Celular Tumoral , Movimento Celular/genética
16.
Front Nutr ; 11: 1370472, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38978696

RESUMO

Background: Early enteral nutrition (EN) is recommended for sepsis management, but its optimal timing and clinical benefits remain uncertain. This study evaluates whether early EN improves outcomes compared to delayed EN in patients with sepsis. Methods: We analyzed data of septic patients from the MIMIC-IV 2.2 database, focusing on those in the Medical Intensive Care Unit (MICU) and Surgical Intensive Care Unit (SICU). Patients who initiated EN within 3 days were classified into the early EN group, while those who started EN between 3 and 7 days were classified into the delayed EN group. Propensity score matching was used to compare outcomes between the groups. Results: Among 1,111 patients, 786 (70.7%) were in the early EN group and 325 (29.3%) were in the delayed EN group. Before propensity score matching, the early EN group demonstrated lower mortality (crude OR = 0.694; 95% CI: 0.514-0.936; p = 0.018) and shorter ICU stays (8.3 [5.2, 12.3] vs. 10.0 [7.5, 14.2] days; p < 0.001). After matching, no significant difference in mortality was observed. However, the early EN group had shorter ICU stays (8.3 [5.2, 12.4] vs. 10.1 [7.5, 14.2] days; p < 0.001) and a lower incidence of AKI stage 3 (49.3% vs. 55.5%; p = 0.030). Subgroup analysis revealed that early EN significantly reduced the 28-day mortality rate in sepsis patients with lactate levels ≤4 mmol/L, with an adjusted odds ratio (aOR) of 0.579 (95% CI: 0.361, 0.930; p = 0.024). Conclusion: Early enteral nutrition may not significantly reduce overall mortality in sepsis patients but may shorten ICU stays and decrease the incidence of AKI stage 3. Further research is needed to identify specific patient characteristics that benefit most from early EN.

17.
Int J Biol Macromol ; 270(Pt 2): 132391, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38761914

RESUMO

Polysaccharides have a wide range of applications due to their excellent antioxidant activity. However, the low purity and unclear structure of polysaccharides have led some researchers to be skeptical about the antioxidant activity of polysaccharides. The current reports on the structure-activity relationship of polysaccharides are sporadic, so there is an urgent need to systematically summarize the antioxidant effects of polysaccharides with clear structures and the relationships between the structures to provide a scientific basis for the development and application of polysaccharides. This paper will systematically elucidate the structure-activity relationship of antioxidant polysaccharides, including the molecular weight, monosaccharide composition, glycosidic linkage, degree of branching, advanced conformation and chemical modification. For the first time, the antioxidant activity of polysaccharides is related to their chemical structure through histogram and radar map, and further studies using principal component analysis and cluster analysis. We critically discussed how the source, chemical structure and chemically modified groups of polysaccharides significantly contribute to their antioxidant activity and summarized the current research status and shortcomings of the structure-activity relationship of antioxidant polysaccharides. This review provides a theoretical basis and new perspective for further research on the structure-activity relationship of antioxidant polysaccharides and the development of natural antioxidants.


Assuntos
Antioxidantes , Polissacarídeos , Polissacarídeos/química , Polissacarídeos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Relação Estrutura-Atividade , Monossacarídeos/química , Peso Molecular
18.
J Cardiothorac Surg ; 19(1): 317, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38824602

RESUMO

BACKGROUND: To investigate the risk factors of pneumothorax of using computed tomography (CT) guidance to inject autologous blood to locate isolated lung nodules. METHODS: In the First Hospital of Putian City, 92 cases of single small pulmonary nodules were retrospectively analyzed between November 2019 and March 2023. Before each surgery, autologous blood was injected, and the complications of each case, such as pneumothorax and pulmonary hemorrhage, were recorded. Patient sex, age, position at positioning, and nodule type, size, location, and distance from the visceral pleura were considered. Similarly, the thickness of the chest wall, the depth and duration of the needle-lung contact, the length of the positioning procedure, and complications connected to the patient's positioning were noted. Logistics single-factor and multi-factor variable analyses were used to identify the risk factors for pneumothorax. The multi-factor logistics analysis was incorporated into the final nomogram prediction model for modeling, and a nomogram was established. RESULTS: Logistics analysis suggested that the nodule size and the contact depth between the needle and lung tissue were independent risk factors for pneumothorax. CONCLUSION: The factors associated with pneumothorax after localization are smaller nodules and deeper contact between the needle and lung tissue.


Assuntos
Neoplasias Pulmonares , Pneumotórax , Nódulo Pulmonar Solitário , Tomografia Computadorizada por Raios X , Humanos , Masculino , Estudos Retrospectivos , Pneumotórax/etiologia , Pneumotórax/diagnóstico por imagem , Feminino , Fatores de Risco , Tomografia Computadorizada por Raios X/métodos , Pessoa de Meia-Idade , Neoplasias Pulmonares/cirurgia , Nódulo Pulmonar Solitário/diagnóstico por imagem , Nódulo Pulmonar Solitário/cirurgia , Idoso , Adulto , Transfusão de Sangue Autóloga/métodos
19.
RSC Adv ; 14(24): 17202-17212, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38808232

RESUMO

Transition metal-based catalysts are widely used in electrocatalysis, especially in the field of water splitting, due to their excellent electrochemical performance, which focuses on improving the efficiency of the complex oxygen evolution reaction (OER) that occurs at the anode. Transition metal-based catalysts will undergo electrochemical surface reconstruction and form (oxy)hydroxide-based hybrids, which consider the actual active sites for OER. So many efforts have been made to know the origin of the effect of electrochemical surface reconstruction on the performance of the OER. Herein, NiCoFe-phosphide catalyst nanosheets were constructed by a simple one-step hydrothermal reaction by adding oleylamine and ethanol to water solvent during the preparation of the catalyst precursor and high-temperature gas-phase phosphating and significantly showed high effectiveness catalytic activity and conductivity in comparison to normal and traditional preparation methods. Electrochemical analysis, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and high-resolution transmission electron microscopy (HRTEM) demonstrate that the surface was constructed during the electrochemical reaction and formed an amorphous layer of MOx(OH)y active sites, which increased the electrochemical surface area and promoted charge transfer. As well, the synthesized NiCoFePx-PNSs catalyst nanosheets exhibit excellent catalytic activity with a low overpotential equal to 259 mV to achieve the OER at a current density of 10 mA cm-2 and a low Tafel slope of 50.47 mV dec-1 which is better than for most reported transition metal-based electrocatalysts. This work provides a new design for a transition metal-based catalyst for OER as well as further insights into the effect of electrochemical surface reconstruction on intrinsic activity and OER performance.

20.
RSC Adv ; 14(15): 10182-10190, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38544941

RESUMO

Transition metal-based catalysts are commonly used for water electrolysis and cost-effective hydrogen fuel production due to their exceptional electrochemical performance, particularly in enhancing the efficiency of the oxygen evolution reaction (OER) at the anode. In this study, a novel approach was developed for the preparation of catalysts with abundant active sites and defects. The MoCoFe-phosphide catalyst nanosheets were synthesized using a simple one-step hydrothermal reaction and chemical vapor deposition-based phosphorization. The resulting MoCoFe-phosphide catalyst nanosheets displayed excellent electrical conductivity and a high number of electrochemically active sites, leading to high electrocatalytic activities and efficient kinetics for the OER. The MoCoFe-phosphide catalyst nanosheets demonstrated remarkable catalytic activity, achieving a low overpotential of only 250 mV to achieve the OER at a current density of 10 mA cm-2. The catalyst also exhibited a low Tafel slope of 43.38 mV dec-1 and maintained high stability for OER in alkaline media, surpassing the performance of most other transition metal-based electrocatalysts. The outstanding OER performance can be attributed to the effects of Mo and Fe, which modulate the electronic properties and structures of CoP. The results showed a surface with abundant defects and active sites with a higher proportion of Co2+ active sites, a larger specific surface area, and improved interfacial charge transfer. X-ray photoelectron spectroscopy (XPS) analysis revealed that the catalyst's high activity originates from the presence of Mo6+/Mo4+ and Co2+/Co3+ redox couples, as well as the formation of active metal (oxy)hydroxide species on its surface.

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