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1.
Int J Biol Macromol ; 273(Pt 2): 132811, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38825282

RESUMO

Atmospheric drying method for fabricating aerogels is considered the most promising way for casting aerogels on a large scale. However, the organic solvent exchange, remaining environmental pollution risk, is a crucial step in mitigating the impact of surface tension during the atmospheric drying process, especially for wet gel formed through the alkoxy-derived sol-gel process, such as melamine-formaldehyde resin (MF) aerogel. Herein, a tough polymer-assisted in situ polymerization was proposed to fabricate MF resin aerogel with a combination of mechanical toughness and strength, enabling it to withstand the capillary force during water evaporation. The monolithic MF resin aerogel through the sol-gel method can be directly prepared without additional network strengthening or organic solvent exchange. The resulting MF resin aerogel exhibits a homogeneous as well as hierarchical structure with macropores and mesopores (~6 µm and ~5 nm), high compressive modulus of 31.8 MPa, self-extinguishing property, and high-temperature thermal insulation with 97 % heat decrease for butane flame combustion. This work presents a straightforward and environmentally friendly method for fabricating MF resin aerogels with nanostructures and excellent performance in open conditions, exhibiting various applications.


Assuntos
Retardadores de Chama , Géis , Triazinas , Triazinas/química , Géis/química , Pressão , Solventes/química , Resinas Sintéticas/química , Dessecação/métodos , Porosidade , Polimerização
2.
Ying Yong Sheng Tai Xue Bao ; 35(4): 985-996, 2024 Apr 18.
Artigo em Chinês | MEDLINE | ID: mdl-38884233

RESUMO

The southwestern region of China is the largest exposed karst area in the world and serves as an important ecological security barrier for the upstream of Yangtze River and Pearl River. Different from the critical zone of non-karst areas, the epikarst, formed by an interwoven network of denudation pores, is the core area of karst critical zone. Water is the most active component that participates in internal material cycle and energy flow within the critical zone. We reviewed relevant research conducted in the southwestern region from three aspects: the characte-rization of critical zone structure, the hydrological processes of soil-epikarst system, and their model simulations. We further proposed potential research hotpots. The main approach involved multi-scale and multi-method integrated observations, as well as interdisciplinary collaboration. Precisely characterizing the eco-hydrological processes of the vegetation-soil-epikarst coupling system was a new trend in the future research. This review would provide scientific reference for further studies on hydrological processes in critical zones and regional hydrological water resource management in karst areas.


Assuntos
Ecossistema , Hidrologia , China , Solo/química , Movimentos da Água , Rios , Água Subterrânea , Conservação dos Recursos Hídricos/métodos , Monitoramento Ambiental
3.
World J Clin Cases ; 12(17): 3144-3150, 2024 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-38898861

RESUMO

BACKGROUND: Myositis ossificans (MO) is a rare disease involving the formation of bone outside the musculoskeletal system. While surgical intervention is the main treatment approach, preventing recurrence and standardized rehabilitation are also crucial. Here, we present a surgical strategy to prevent the recurrence of MO. CASE SUMMARY: A 28-year-old female patient was admitted for the first time for a comminuted fracture of the left olecranon. However, incorrect postoperative rehabilitation resulted in the development of elbow joint stiffness with ectopic ossification, causing a loss of normal range of motion. The patient was diagnosed with MO based on physical examination, X-ray findings, and clinical presentation. We devised a surgical strategy to remove MO, followed by fixation with an Ilizarov frame, and implemented a scientifically reasonable rehabilitation plan. The surgery lasted for 3 h with an estimated blood loss of 45 mL. A drainage tube was placed after surgery, and fluid was aspirated through ultrasound-guided puncture. The patient experienced a significant reduction in joint stiffness after surgery. In the final follow-up at 9 mouths, there was evident improvement in the range of motion of the elbow joint, and no other symptoms were reported. CONCLUSION: The Ilizarov frame is an advantageous surgical technique for facilitating rehabilitation after MO removal. It offers benefits such as passive recovery, individualized treatment, and prompt recovery.

4.
Pest Manag Sci ; 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38877352

RESUMO

BACKGROUND: Understanding how parasitoids respond to temperature is crucial for improving biological control strategies under the context of global warming. This study examined the suitability of Myzus persicae and its parasitoid Aphidius gifuensis to varying temperature conditions, as well as the stage-specific response of A. gifuensis to high temperatures. RESULTS: High temperatures had a significant impact on the both M. persicae and A. gifuensis. When exposed to 36°C, M. persicae developed more slowly and produced smaller adults compared to control, regardless of the duration of exposure (2, 4 or 6 h); additionally, the survival rate of M. persicae nymphs sharply decreased under these conditions. Exposure to 36°C for 4 h negatively impacted the development of A. gifuensis. Female parasitoids exposed to 32°C developed into smaller adults, whereas males exposed to all three temperature levels were smaller compared to control group. Female parasitoids exposed to high temperatures, regardless of the specific heat level and duration, exhibited reduced longevity and decreased fecundity. None of the parasitoids exposed to 36°C for 6 h daily developed into adults. Heat treated during early developmental stages (2 and 4 days old) had a greater influence on parasitoid development, whereas heat treatment at 4 and 6 days old had a more significant impact on its fecundity. CONCLUSION: High temperatures not only directly affected the performance of A. gifuensis, but also exerted indirect effects by influencing the quality of the host aphids M. persicae. The deleterious effects of high temperature on larvae can persist into the adult stage, affecting the longevity and reproduction of adults. These findings are important for the utilization of A. gifuensis in the control of M. persicae in warming environments. © 2024 Society of Chemical Industry.

5.
World J Gastrointest Surg ; 16(4): 1030-1042, 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38690053

RESUMO

Blastomas, characterized by a mixture of mesenchymal, epithelial, and undifferentiated blastematous components, are rare malignant neoplasms originating from precursor blast cells. This review focuses on digestive system blastomas in adult patients, including gastroblastoma, hepatoblastoma, and pancreatoblastoma. Gastroblastoma is a biphasic, epitheliomesenchymal tumor, with only sixteen cases reported to date. In addition to the characteristic histology, metastasis-associated lung adenocarcinoma transcript 1 - glioma-associated oncogene homolog 1 gene fusion is typical, although recently novel ewing sarcoma breakpoint region 1 - c-terminal binding protein 1 and patched 1 - glioma-associated oncogene homolog 2 fusions have been described. Hepatoblastoma is exceptionally rare in adults and can show a variety of histologic patterns which may cause diagnostic difficulty. Pancreatoblastoma, primarily a pediatric tumor, displays acinar differentiation and squamoid nests with other lines of differentiation also present, especially neuroendocrine. Diagnostic approaches for these blastomas include a combination of imaging modalities, histopathological examination, and molecular profiling. The treatment generally involves surgical resection, which may be supplemented by chemotherapy or radiotherapy in some cases. Prognoses vary with gastroblastoma generally showing favorable outcomes post-surgery whereas hepatoblastoma and pancreatoblastoma often have poorer outcomes, particularly in the setting of metastases. This review highlights the complexity of diagnosing and managing these rare adult blastomas as well as the need for ongoing research to better understand their pathogenesis and improve treatment strategies.

6.
Chin J Traumatol ; 27(4): 200-210, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38763812

RESUMO

PURPOSE: Head injury criterion (HIC) companied by a rotation-based metric was widely believed to be helpful for head injury prediction in road traffic accidents. Recently, the Euro-New Car Assessment Program utilized a newly developed metric called diffuse axonal multi-axis general evaluation (DAMAGE) to explain test device for human occupant restraint (THOR) head injury, which demonstrated excellent ability in capturing concussions and diffuse axonal injuries. However, there is still a lack of comprehensive understanding regarding the effectiveness of using DAMAGE for Hybrid Ⅲ 50th percentile male dummy (H50th) head injury assessment. The objective of this study is to determine whether the DAMAGE could capture the risk of H50th brain injury during small overlap barrier tests. METHODS: To achieve this objective, a total of 24 vehicle crash loading curves were collected as input data for the multi-body simulation. Two commercially available mathematical dynamic models, namely H50th and THOR, were utilized to investigate the differences in head injury response. Subsequently, a decision method known as simple additive weighting was employed to establish a comprehensive brain injury metric by incorporating the weighted HIC and either DAMAGE or brain injury criterion. Furthermore, 35 sets of vehicle crash test data were used to analyze these brain injury metrics. RESULTS: The rotational displacement of the THOR head is significantly greater than that of the H50th head. The maximum linear and rotational head accelerations experienced by H50th and THOR models were (544.6 ± 341.7) m/s2, (2468.2 ± 1309.4) rad/s2 and (715.2 ± 332.8) m/s2, (3778.7 ± 1660.6) rad/s2, respectively. Under the same loading condition during small overlap barrier (SOB) tests, THOR exhibits a higher risk of head injury compared to the H50th model. It was observed that the overall head injury response during the small overlap left test condition is greater than that during the small overlap right test. Additionally, an equation was formulated to establish the necessary relationship between the DAMAGE values of THOR and H50th. CONCLUSION: If H50th rather than THOR is employed as an evaluation tool in SOB crash tests, newly designed vehicles are more likely to achieve superior performance scores. According to the current injury curve for DAMAGE and brain injury criterion, it is highly recommended that HIC along with DAMAGE was prioritized for brain injury assessment in SOB tests.


Assuntos
Acidentes de Trânsito , Lesão Axonal Difusa , Humanos , Masculino , Manequins , Aceleração
7.
Heliyon ; 10(9): e29896, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38707273

RESUMO

In this study, ionic liquids (ILs) were used as organic modifiers by introducing montmorillonite nanolayers containing potential C and N active sites between the montmorillonite nanolayers. Organically modified montmorillonite (ILs-Mt-p) was further prepared by high-temperature pyrolysis under N2 and used for the removal of ofloxacin (OFL) by activated peroxymonosulfate (PMS). Combined with XPS and other characterization analyses, it was found that the catalyst materials prepared from different organic modifiers had similar surface functional groups and graphitized structures, but contained differences in the types and numbers of C and N active sites. The catalyst (3CPC-Mt-p) obtained after pyrolysis of montmorillonite modified with cetylpyridinium chloride (CPC) had optimal catalytic performance, in which graphitic C, graphitic N, and carbonyl group (C[bond, double bond]O) could synergistically promote the activation of PMS by electron transfer, and 77.3 % of OFL could be removed within 60 min. The effects of OFL concentration, initial pH, and anions on the effects of OFL removal by the 3CPC-Mt-p/PMS system were further investigated. Satisfactory degradation results were obtained over a wide pH range. Cl- promoted the system to degrade OFL, while the presence of SO42-, H2PO4- and HA showed some inhibition, but overall the 3CPC-Mt-p catalysts had a strong anti-interference ability, showing good application prospects. The quenching experiments and EPR tests showed that O2-- and 1O2 in the 3CPC-Mt-p/PMS system were the main reactive oxygen species for the degradation of OFL, and •OH was also involved in the reaction. This study provides ideas for the construction and modulation of active sites in mineral materials such as montmorillonite and broadens the application of montmorillonite composite catalysts in advanced oxidation processes for the treatment of antibiotic wastewater.

8.
Adv Mater ; 36(28): e2400059, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38684087

RESUMO

Materials that can provide reliable electromagnetic interference (EMI) shielding in highly oxidative atmosphere at elevated temperature are indispensable in the fast-developing aerospace field. However, most of conductor-type EMI shielding materials such as metals can hardly withstand the high-temperature oxidation, while the conventional dielectric-type materials cannot offer sufficient shielding efficiency in gigahertz (GHz) frequencies. Here, a highly deficient medium-entropy (ME) perovskite ceramic as an efficient EMI shielding material in harsh environment, is demonstrated. The synergistic effect of entropy stabilization and aliovalent substitution on A-site generate abnormally high concentration of Ti and O vacancies that are stable under high-temperature oxidation. Due to the clustering of vacancies, the highly deficient perovskite ceramic exhibits giant complex permittivity and polarization loss in GHz, leading to the specific EMI shielding effectiveness above 30 dB/mm in X-band even after 100 h of annealing at 1000 °C in air. Along with the low thermal conductivity, the aliovalent ME perovskite can serve as a bifunctional shielding material for applications in aircraft engines and reusable rockets.

9.
Fitoterapia ; 176: 105973, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38663560

RESUMO

The growing incidence of Clostridium difficile associated diarrhea (CDAD) underscores the urgency for potent treatments. This research delves into the therapeutic potential of Scutellaria baicalensis Georgi (Lamiaceae) root (SR) in addressing CDAD and its influence on gut microbiota. Using a CDAD mouse model and fidaxomicin as a control, SR's impact was measured through diarrhea symptoms, colonic histopathology, and C. difficile toxin levels. Employing the PacBio platform, 16S rRNA full-length gene sequencing analyzed the gut microbial composition and the effect of SR. Results revealed SR considerably alleviated diarrhea during treatment and restoration phases, with a marked decrease in colonic inflammation. C. difficile toxin levels dropped significantly with SR treatment (P < 0.001). While SR didn't augment gut microbiota's overall abundance, it enhanced its diversity. It restored levels of Proteobacteria and Bacteroidetes, reduced Akkermansia spp. and Enterococcus spp. proportions, and modulated specific bacterial species' abundance. In essence, SR effectively mitigates CDAD symptoms, curtails inflammatory reactions, and beneficially restructures gut microbiota, suggesting its potential in advanced CDAD clinical intervention.


Assuntos
Clostridioides difficile , Diarreia , Microbioma Gastrointestinal , Extratos Vegetais , Scutellaria baicalensis , Microbioma Gastrointestinal/efeitos dos fármacos , Animais , Diarreia/microbiologia , Diarreia/tratamento farmacológico , Camundongos , Scutellaria baicalensis/química , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Masculino , Infecções por Clostridium/tratamento farmacológico , Modelos Animais de Doenças , RNA Ribossômico 16S/genética , Camundongos Endogâmicos C57BL , Colo/microbiologia
10.
Brain Pathol ; : e13261, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38602336

RESUMO

Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease, pathologically characterized by TDP-43 aggregates. Recent evidence has been indicated that phosphorylated TDP-43 (pTDP-43) is present not only in motor neurons but also in muscle tissues. However, it is unclear whether testing pTDP-43 aggregation in muscle tissue would assist in the diagnosis of ALS. We propose three key questions: (i) Is aggregation of pTDP-43 detectable in routine biopsied muscles? (ii) Can detection of pTDP-43 aggregation discriminate between ALS and non-ALS patients? (iii) Can pTDP-43 aggregation be observed in the early stages of ALS? We conducted a diagnostic study comprising 2 groups: an ALS group in which 18 cases underwent muscle biopsy screened from a registered ALS cohort consisting of 802 patients and a non-ALS control group, in which we randomly selected 54 muscle samples from a biospecimen bank of 684 patients. Among the 18 ALS patients, 3 patients carried pathological GGGGCC repeats in the C9ORF72 gene, 2 patients carried SOD1 mutations, and 7 patients were at an early stage with only one body region clinically affected. The pTDP-43 accumulation could be detected in routine biopsied muscles, including biceps brachii, deltoid, tibialis anterior, and quadriceps. Abnormal aggregation of pTDP-43 was present in 94.4% of ALS patients (17/18) compared to 29.6% of non-ALS controls (16/54; p < 0.001). The pTDP-43 aggregates were mainly close to the sarcolemma. Using a semi-quantified pTDP-43 aggregates score, we applied a cut-off value of 3 as a diagnostic biomarker, resulting in a sensitivity of 94.4% and a specificity of 83.3%. Moreover, we observed that accumulation of pTDP-43 occurred in muscle tissues prior to clinical symptoms and electromyographic lesions. Our study provides proof-of-concept for the detection of pTDP-43 accumulation via routine muscle biopsy which may serve as a novel biomarker for diagnosis of ALS.

11.
Zhongguo Zhong Yao Za Zhi ; 49(4): 1000-1006, 2024 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-38621907

RESUMO

This study aims to investigate the effect and mechanism of Maxingshigan Decoction on inflammation in the rat model of cough variant asthma(CVA). The SPF-grade SD rats of 6-8 weeks were randomized into normal, model, Montelukast sodium, and low-, medium-, and high-dose Maxing Shigan Decoction groups, with 8 rats in each group. The CVA rat model was induced by ovalbumin(OVA) and aluminum hydroxide sensitization and ovalbumin stimulation. The normal group and model group were administrated with equal volume of normal saline by gavage, and other groups with corresponding drugs by gavage. After the experiment, the number of white blood cells in blood and the levels of interleukin-6(IL-6), interleukin-10(IL-10), and tumor necrosis factor-α(TNF-α) in the serum were measured. The lung tissue was stained with hematoxylin-eosin(HE). Western blot was employed to determine the protein levels of nuclear factor-κB(NF-κB), Toll-like receptor 4(TLR4), myeloid differentiation protein(MyD88), and mitogen-activated protein kinase(MAPK) in the lung tissue. Real-time PCR was carried out to measure the mRNA levels of TLR4 and MyD88 in the lung tissue. Compared with the normal group, the model group showed increased white blood cells, elevated IL-6 and TNF-α levels(P<0.01), lowered IL-10 level(P<0.01), up-regulated protein levels of TLR4, MyD88, p-p65/NF-κB p65, and p-p38 MAPK/p38 MAPK(P<0.01) and mRNA levels of TLR4 and MyD88(P<0.01) in the lung tissue. HE staining showed obvious infiltration of inflammatory cells around the airway and cell disarrangement in the model group. Compared with the model group, Montelukast sodium and high-dose Maxing Shigan Decoction reduced the white blood cells, lowered the IL-6 and TNF-α levels(P<0.01), and elevated the IL-10 level(P<0.01). Moreover, they down-regulated the protein levels of TLR4, MyD88, p-p65/NF-κB p65, p-p38 MAPK/p38 MAPK in the lung tissue(P<0.01) and the mRNA levels of TLR4 and MyD88 in the lung tissue(P<0.01). HE staining showed that Montelukast sodium and high-dose Maxing Shigan Decoction reduced inflammatory cell infiltration and cell disarrangement. The number of white blood cells, the levels of IL-10 and TNF-α in the serum, the protein levels of TLR4, MyD88, p-p65/NF-κB p65, and p-p38 MAPK/p38 MAPK, and the mRNA levels of TLR4 and MyD88 in the lung tissue showed no significant differences between the Montelukast sodium group and high-dose Maxing Shigan Decoction group. Maxing Shigan Decoction can inhibit airway inflammation in CVA rats by inhibiting the activation of TLR4/MyD88/NF-κB and p38 MAPK signaling pathways.


Assuntos
Acetatos , Variante Tussígena da Asma , Ciclopropanos , NF-kappa B , Quinolinas , Sulfetos , Ratos , Animais , NF-kappa B/genética , NF-kappa B/metabolismo , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Interleucina-10/genética , Transdução de Sinais , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Ratos Sprague-Dawley , Ovalbumina , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Inflamação , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , RNA Mensageiro
12.
Heliyon ; 10(7): e28090, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38571596

RESUMO

Background: Lung adenocarcinoma (LUAD) has a complex tumor heterogeneity. Our research attempts to clearness LUAD subtypes and build a reliable prognostic signature according to the activity changes of the hallmark and immunologic gene sets. Methods: According to The Cancer Genome Atlas (TCGA) - LUAD dataset, changes in marker and immune gene activity were analyzed, followed by identification of prognosis-related differential gene sets (DGSs) and their related LUAD subtypes. Survival analysis, correlation with clinical characteristics, and immune microenvironment assessment for subtypes were performed. Moreover, the differentially expressed genes (DEGs) between different subtypes were identified, followed by the construction of a prognostic risk score (RS) model and nomogram model. The tumor mutation burden (TMB) and tumor immune dysfunction and exclusion (TIDE) of different risk groups were compared. Results: Two LUAD subtypes were determined according to the activity changes of the hallmark and immunologic gene sets. Cluster 2 had worse prognosis, more advanced tumor and clinical stages than cluster 1. Moreover, a prognostic RS signature was established using two LUAD subtype-related DEGs, which could stratify patients at different risk levels. Nomogram model incorporated RS and clinical stage exerted good prognostic performance in LUAD patients. A shorter survival time and higher TMB were observed in the high-risk patients. Conclusions: Our findings revealed that our constructed prognostic signature could exactly predict the survival status of LUAD cases, which was helpful in predicting the prognosis and guiding personalized therapeutic strategies for LUAD.

13.
Adv Sci (Weinh) ; 11(21): e2309348, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38498682

RESUMO

Tertiary lymphoid structure (TLS) can predict the prognosis and sensitivity of tumors to immune checkpoint inhibitors (ICIs) therapy, whether it can be noninvasively predicted by radiomics in hepatocellular carcinoma with liver transplantation (HCC-LT) has not been explored. In this study, it is found that intra-tumoral TLS abundance is significantly correlated with recurrence-free survival (RFS) and overall survival (OS). Tumor tissues with TLS are characterized by inflammatory signatures and high infiltration of antitumor immune cells, while those without TLS exhibit uncontrolled cell cycle progression and activated mTOR signaling by bulk and single-cell RNA-seq analyses. The regulators involved in mTOR signaling (RHEB and LAMTOR4) and S-phase (RFC2, PSMC2, and ORC5) are highly expressed in HCC with low TLS. In addition, the largest cohort of HCC patients is studied with available radiomics data, and a classifier is built to detect the presence of TLS in a non-invasive manner. The classifier demonstrates remarkable performance in predicting intra-tumoral TLS abundance in both training and test sets, achieving areas under receiver operating characteristic curve (AUCs) of 92.9% and 90.2% respectively. In summary, the absence of intra-tumoral TLS abundance is associated with mTOR signaling activation and uncontrolled cell cycle progression in tumor cells, indicating unfavorable prognosis in HCC-LT.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Transplante de Fígado , Transdução de Sinais , Serina-Treonina Quinases TOR , Estruturas Linfoides Terciárias , Humanos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Serina-Treonina Quinases TOR/metabolismo , Serina-Treonina Quinases TOR/genética , Prognóstico , Masculino , Estudos Retrospectivos , Transplante de Fígado/métodos , Pessoa de Meia-Idade , Feminino , Estruturas Linfoides Terciárias/genética , Transdução de Sinais/genética , Adulto , Idoso , Análise de Sobrevida
14.
Nat Commun ; 15(1): 2726, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38548723

RESUMO

Polymeric materials, rich in carbon, hydrogen, and oxygen elements, present substantial fire hazards to both human life and property due to their intrinsic flammability. Overcoming this challenge in the absence of any flame-retardant elements is a daunting task. Herein, we introduce an innovative strategy employing catalytic polymer auto-pyrolysis before combustion to proactively release CO2, akin to possessing responsive CO2 fire extinguishing mechanisms. We demonstrate that potassium salts with strong nucleophilicity (such as potassium formate/malate) can transform conventional polyurethane foam into materials with fire safety through rearrangement. This transformation results in the rapid generation of a substantial volume of CO2, occurring before the onset of intense decomposition, effectively extinguishing fires. The inclusion of just 1.05 wt% potassium formate can significantly raise the limiting oxygen index of polyurethane foam to 26.5%, increase the time to ignition by 927%, and tremendously reduce smoke toxicity by 95%. The successful application of various potassium salts, combined with a comprehensive examination of the underlying mechanisms, underscores the viability of this strategy. This pioneering catalytic approach paves the way for the efficient and eco-friendly development of polymeric materials with fire safety.

15.
Heliyon ; 10(5): e27112, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38449592

RESUMO

Thrombotic complications of atrial fibrillation continue to pose a significant challenge in clinical practice today. Left atrial appendage occlusion (LAAO) has emerged as a promising alternative to oral anticoagulation for high-risk patients with atrial fibrillation. However, despite the potential benefits, there is still the possibility of life-threatening complications such as device dislocation. In this case study, we present a patient who experienced severe hemodynamic disturbances due to the embolization of LAAO device into the left ventricular outflow tract, resulting in a torn mitral valve and secondary massive mitral regurgitation, just 3 hours after the procedure. As a result, emergent surgical intervention was required to remove the device and repair the mitral valve. We also conducted a review of previous studies on the retrieval of dislodged left atrial appendage occluders through surgical procedures. It is crucial to maintain vigilance, foster interdisciplinary collaboration, and respond promptly to ensure the safety and efficacy of LAAO procedures.

16.
Signal Transduct Target Ther ; 9(1): 33, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38369543

RESUMO

Pyrogen, often as a contaminant, is a key indicator affecting the safety of almost all parenteral drugs (including biologicals, chemicals, traditional Chinese medicines and medical devices). It has become a goal to completely replace the in vivo rabbit pyrogen test by using the in vitro pyrogen test based on the promoted 'reduction, replacement and refinement' principle, which has been highly considered by regulatory agencies from different countries. We used NF-κB, a central signalling molecule mediating inflammatory responses, as a pyrogenic marker and the monocyte line THP-1 transfected with a luciferase reporter gene regulated by NF-κB as an in vitro model to detect pyrogens by measuring the intensity of a fluorescence signal. Here, we show that this test can quantitatively and sensitively detect endotoxin (lipopolysaccharide from different strains) and nonendotoxin (lipoteichoic acid, zymosan, peptidoglycan, lectin and glucan), has good stability in terms of NF-κB activity and cell phenotypes at 39 cell passages and can be applied to detect pyrogens in biologicals (group A & C meningococcal polysaccharide vaccine; basiliximab; rabies vaccine (Vero cells) for human use, freeze-dried; Japanese encephalitis vaccine (Vero cells), inactivated; insulin aspart injection; human albumin; recombinant human erythropoietin injection (CHO Cell)). The within-laboratory reproducibility of the test in three independent laboratories was 85%, 80% and 80% and the interlaboratory reproducibility among laboratories was 83.3%, 95.6% and 86.7%. The sensitivity (true positive rate) and specificity (true negative rate) of the test were 89.9% and 90.9%, respectively. In summary, the test provides a novel alternative for pyrogen detection.


Assuntos
NF-kappa B , Pirogênios , Animais , Chlorocebus aethiops , Coelhos , Humanos , Pirogênios/farmacologia , Pirogênios/química , Células Vero , Reprodutibilidade dos Testes , Linhagem Celular
17.
World J Gastrointest Oncol ; 16(1): 1-7, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38292836

RESUMO

Four major studies (Checkmate577, Keynote-590, Checkmate649 and Attraction-4) of locally advanced esophageal cancer published in 2020 have established the importance of immunotherapy, represented by anti-programmed death protein (PD)-1 in postoperative adjuvant treatment and advanced first-line treatment of locally advanced or advanced esophageal cancer and esophagogastric junction cancer, from the aspects of proof of concept, long-term survival, overall survival rate and progression-free survival. For unresectable or inoperable nonmetastatic esophageal cancer, concurrent radiotherapy and chemotherapy is the standard treatment recommended by various guidelines. Because its curative effect is still not ideal, it is necessary to explore radical radiotherapy and chemotherapy in the future, and it is considered to be promising to combine them with immunotherapeutic drugs such as anti-PD-1. This paper mainly discusses how to combine radical concurrent radiotherapy and chemotherapy with immunotherapy for unresectable local advanced esophageal cancer.

18.
J Pharm Biomed Anal ; 239: 115911, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38091818

RESUMO

Polygonatum odoratum (Yu-Zhu) can be utilized to treat the digestive and respiratory illness. Previous studies have revealed that the underlying therapeutic mechanism of P. odoratum polysaccharides (POPs) is associated with remodeling the gut microbiota. However, POPs in terms of the chemical composition and fermentation activities have been understudied. Here we developed the three-level fingerprinting approaches to characterize the structures of POPs and probed into the beneficial effects on promoting the growth and fermentation of Lactobacillus johnsonii. POPs were prepared by water decoction followed by alcohol sedimentation, while trifluoroacetic acid under different conditions to prepare the hydrolyzed oligosaccharides and monosaccharides. POPs exhibited three main molecular distribution of 601-620 kDa, 4.12-6.09 kDa, and 3.57-6.02 kDa. Hydrolyzed oligosaccharides with degree of polymerization (DP) 2-13 got primarily characterized by analyzing the rich fragmentation information obtained by hydrophilic interaction chromatography/ion mobility-quadrupole time-of-flight mass spectrometry (HILIC/IM-QTOF-MS). Amongst them, the DP5 oligosaccharide was characterized as 1,6,6-kestopentaose. The molecular ratio of Fru: Ara: Glc: Gal: Xyl was 87.72: 0.30: 11.56: 0.19: 0.23. In vitro fermentation demonstrated that 4.5 mg/mL of POPs could significantly promote the growth of L. johnsonii. Co-cultivated with 4.5 mg/mL of POPs, L. johnsonii exhibited stronger antimicrobial activity against Klebsiella pneumoniae. The concentrations of short-chain fatty acids in the POPs-lactobacilli fermented products, including acetic acid, isobutyric acid, and isovaleric acid, were increased. Conclusively, POPs represent the promising prebiotic candidate to facilitate lactobacilli, which is associated with exerting the health benefits.


Assuntos
Microbioma Gastrointestinal , Lactobacillus johnsonii , Polygonatum , Polygonatum/química , Polissacarídeos/farmacologia , Polissacarídeos/química , Oligossacarídeos , Lactobacillus
19.
Nat Chem ; 16(1): 114-121, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37723258

RESUMO

Single-crystal X-ray diffraction is a powerful characterization technique that enables the determination of atomic arrangements in crystalline materials. Growing or retaining large single crystals amenable to it has, however, remained challenging with covalent organic frameworks (COFs), especially suffering from post-synthetic modifications. Here we show the synthesis of a flexible COF with interpenetrated qtz topology by polymerization of tetra(phenyl)bimesityl-based tetraaldehyde and tetraamine building blocks. The material is shown to be flexible through its large, anisotropic positive thermal expansion along the c axis (αc = +491 × 10-6 K-1), as well as through a structural transformation on the removal of solvent molecules from its pores. The as-synthesized and desolvated materials undergo single-crystal-to-single-crystal transformation by reduction and oxidation of its imine linkages to amine and amide ones, respectively. These redox-induced linkage conversions endow the resulting COFs with improved stability towards strong acid; loading of phosphoric acid leads to anhydrous proton conductivity up to ca. 6.0 × 10-2 S cm-1.

20.
Adv Mater ; 36(6): e2308153, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37939686

RESUMO

Memristor with low-power, high density, and scalability fulfills the requirements of the applications of the new computing system beyond Moore's law. However, there are still nonideal device characteristics observed in the memristor to be solved. The important observation is that retention and speed are correlated parameters of memristor with trade off against each other. The delicately modulating distribution and trapping level of defects in electron migration-based memristor is expected to provide a compromise method to address the contradictory issue of improving both switching speed and retention capability. Here, high-performance memristor based on the structure of ITO/Ni single-atoms (NiSAs/N-C)/Polyvinyl pyrrolidone (PVP)/Au is reported. By utilizing well-distributed trapping sites , small tunneling barriers/distance and high charging energy, the memristor with an ultrafast switching speed of 100 ns, ultralong retention capability of 106  s, a low set voltage (Vset ) of ≈0.7 V, a substantial ON/OFF ration of 103 , and low spatial variation in cycle-to-cycle (500 cycles) and device-to-device characteristics (128 devices) is demonstrated. On the premise of preserving the strengths of a fast switching speed, this memristor exhibits ultralong retention capability comparable to the commercialized flash memory. Finally, a memristor ratioed logic-based combinational memristor array to realize the one-bit full adder is further implemented.

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