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1.
Front Microbiol ; 15: 1296059, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38322313

RESUMO

Objective: This study aimed to evaluate the clinical value of dynamic monitoring of neutrophil/lymphocyte ratio (NLR), APACHE II (Acute Physiology and Chronic Health Evaluation II) score, and Sequential Organ Failure Assessment (SOFA) score in predicting 28-day prognosis and drug resistance in patients with bloodstream infection with Acinetobacter baumannii-calcoaceticus complex (Abc complex). Patients and methods: In this research, individuals admitted to Tianjin Medical University General Hospital from January 2017 to March 2023 with bloodstream infections and a minimum of one Abc complex positive blood culture were chosen. The risk factors for the 28-day prognosis and drug resistance were analyzed using logistic regression. The NLR, APACHE II score, and SOFA score were evaluated for predicting 28-day prognosis and drug resistance using an ROC curve analysis. The data were analyzed using R Studio to find correlations and conduct survival analysis with the Kaplan-Meier method. Results: The final statistical analysis included a total of 129 patients with bloodstream infections caused by Abc complex. Independent risk factors predicting mortality within 28 days were identified as follows: the SOFA score and APACHE II scores at 24 h, and APACHE II scores at 72 h after the onset of blood infection (p < 0.05). NLR, SOFA score, and APACHE II score did not predict drug resistance. Patients with Carbapenem-resistant Acinetobacter baumannii-calcoaceticus complex (CRAB) had shorter survival times than those with carbapenem-sensitive strains (40.77 days vs. 47.65 days, respectively, p = 0.0032). Conclusion: The prognosis of Abc complex bloodstream infection is affected by both SOFA and APACHE II scores. Both scoring systems have similar prognostic values at different time points after infection, but for computational convenience, it is recommended to use the SOFA score. NLR exhibits limited effectiveness in predicting mortality within 28 days. Carbapenem-resistant individuals with Abc complex experience significantly reduced survival time. None of the three factors-SOFA score, APACHE II score, and NLR-can early predict the occurrence of CRAB infections effectively.

2.
Phys Rev Lett ; 132(5): 056203, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38364171

RESUMO

Friction is responsible for about one-third of the primary energy consumption in the world. So far, a thorough atomistic understanding of the frictional energy dissipation mechanisms is still lacking. The Amontons' law states that kinetic friction is independent of the sliding velocity while the Prandtl-Tomlinson model suggests that damping is proportional to the relative sliding velocity between two contacting objects. Through careful analysis of the energy dissipation process in atomic force microscopy measurements, here we propose that damping force is proportional to the tip oscillation speed induced by friction. It is shown that a physically well-founded damping term can better reproduce the multiple peaks in the velocity-dependent friction force observed in both experiments and molecular dynamics simulations. Importantly, the analysis gives a clear physical picture of the dynamics of energy dissipation in different friction phases, which provides insight into long-standing puzzles in sliding friction, such as velocity weakening and spring-stiffness-dependent friction.

3.
Int J Biol Macromol ; 263(Pt 2): 130435, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38408585

RESUMO

Currently, it has long been considered a challenge to provide sustainable additives for polylactide (PLA) in green way to endow it excellent comprehensive properties. Given the flammability and unsatisfactory crystallization performance of PLA, a furan-based phosphate furfurylamine trimethylphosphate (FATMP) was synthesized from 2-furfurylamine and amino trimethylphosphonic acid by a simple hydration reaction, and the PLA/FATMP composites were prepared by melting blending process. The tensile performance, crystallization behaviors, flame retardancy, and flame-retardant mechanism received special attention. Results showed that the incorporation of only 3 wt% FATMP could indeed increase the LOI value of PLA from 19.8 to 27.3 %, and simultaneously acquired V-0 rating in the vertical burning test owing to the favorable synergistic effect between the vapor phase and the condensed phase. Additionally, the half-crystallization time of PLA was decreased from 12.4 to 5.1 mins with the addition of FATMP, which acted as a nucleating agent. More appealingly, the tensile performance of PLA/FATMP composites was also well maintained. In general, the PLA/FATMP composites we proposed could be promising candidates in application fields where favorable flame retardancy and crystallization ability are required.


Assuntos
Organofosfatos , Fosfatos , Poliésteres , Aminoácidos , Furanos
4.
Int J Biol Macromol ; 261(Pt 2): 129871, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38309396

RESUMO

The packaging industry demands improved eco-friendly materials with new and enhanced properties. In this context, bio-nanocomposite films with antimicrobial and UV-shielding properties based on modified cellulose nanocrystals/polycaprolactone (MCNC/PCL) were fabricated via solution casting method, and then food packaging simulation was carried out. CNCs were obtained by acid hydrolysis followed by successful functionalization with Quaternary ammonium surfactant, confirmed by FTIR, XPS, XRD, TEM, and DLS analyses. Furthermore, the morphological, physical, antibacterial, and food packaging properties of all prepared films were investigated. Results showed that the mechanical, UV blocking, barrier properties, and antibacterial activity of all composite films were remarkably improved. Particularly, the addition of 3 wt% MCNC increased the tensile strength and elongation at break by 27.5 % and 20.0 %, respectively. Moreover, the permeability of O2, CO2, and water vapor dramatically reduced by 97.6 %, 96.7 %, and 49.8% compared to the Neat PCL. Further, the UV-blocking properties of the composite films were significantly improved. The antimicrobial properties of MCNC/PCL films showed good antimicrobial properties against S. aureus. Finally, cherry packaged with 1 and 3 wt% MCNC films exhibited satisfactory freshness after 22 days of preservation. Overall, the fabricated PCL nanocomposite films can be utilized in the food packaging industry.


Assuntos
Anti-Infecciosos , Nanocompostos , Nanopartículas , Poliésteres , Embalagem de Alimentos , Staphylococcus aureus , Celulose/química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Nanopartículas/química , Antibacterianos/farmacologia , Nanocompostos/química
5.
Int J Biol Macromol ; 254(Pt 1): 127701, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37907179

RESUMO

3D-printing provides a feasible technique for realizing new materials into structural and intelligent parts. In this work, biomass furan-based polyesters poly (ethylene furanoate) (PEF), poly (trimethylene furanoate) (PTF), and poly (butylene furanoate) (PBF) were successfully synthesized in a 5 L reactor through the melt polycondensation process and fabricated into 3D-printing feedstocks. It was demonstrated that the three furan-based polyesters were additively-manufactured into complicated structures. Besides, the mechanical and thermal properties of furan-based polyesters could be tailored by the chain length of diol monomer. The mechanical performance of 3D-printed PEF, PTF and PBF were characterized and compared with commercial filaments. The tensile strength of PEF and PTF could reach 74.6 and 63.8 MPa respectively, which exhibited superior tensile property to poly(ether-ether-ketone) (PEEK), polyamide (PA) and polylactic acid (PLA). Meanwhile, the compression results demonstrated that the PEF and PTF possessed comparable energy absorption capacity with PEEK and PLA respectively, which indicated excellent mechanical properties of furan-based polyesters. It was interesting to find that the 3D-printed structures including solid cube, bionic flower and lattice structures were employed to prove that the PTF possessed excellent shape memory properties. Therefore, the proposed biomass furan-based polymers would offer more freedom in the field of 3D-printing.


Assuntos
Poliésteres , Polímeros , Biomassa , Éteres , Impressão Tridimensional
6.
PLoS One ; 18(11): e0289912, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38019761

RESUMO

BACKGROUND: The BushenHuoxue formula (BSHX) has been previously demonstrated to ameliorate osteoporosis, but the mechanisms underlying this phenomenon are currently unclear. The present study aims at investigating the mechanisms that BSHX induces osteogenesis. METHODS: We established an osteoporosis model in rats by bilateral ovariectomy and then treated the rats with an osteogenic inducer (dexamethasone, ß-sodium glycerophosphate and Vitamin C) and BSHX. After that, bone marrow density and histopathological bone examination were evaluated by using HE staining and immunohistochemistry, respectively. We also assessed the differentiation of bone marrow mesenchymal stem cells (BMSCs) into osteoblasts by using immunofluorescence staining. ALP, BMP, and COL1A1 levels were determined by ELISA. We identified genes involved in pathogenesis of osteoporosis through Gene Expression Omnibus (GEO) database and subsequently selected Hedgehog signaling-related genes Shh, Ihh, Gli2, and Runx2 for assessment via qRT-PCR and ELISA, Western blotting. Network pharmacology analysis was performed to identify bioactive metabolites of BSHX. RESULTS: BSHX treatment in osteoporosis model rats promoted tightening of the morphological structure of the trabecular bone and increased the bone mineral density (BMD). BSHX also increased levels of osteoblast makers ALP, BMP, and COL1A1. Additionally, bioinformatics analysis of the GEO dataset showed that Hedgehog signaling pathway was involved in pathogenesis of osteoporosis, especially related genes Shh, Ihh, Gli2, and Runx2. Remarkably, BHSX upregulated these genes indispensably involved in the osteogenesis-related Hedgehog signaling pathway in both bone tissue and BMSCs. Importantly, we identified that quercetin was the active compounds that involved in the mechanism of BSHX-improved OP via affecting Hedgehog-related genes. CONCLUSION: Our results indicate that BSHX promotes osteogenesis by improving BMSC differentiation into osteoblasts via increased expression of Hedgehog signaling-related genes Shh, Ihh, Gli2, and Runx2, and quercetin was the bioactive compound of BSHX.


Assuntos
Osteogênese , Osteoporose , Feminino , Ratos , Animais , Proteínas Hedgehog/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Quercetina/metabolismo , Células Cultivadas , Osteoporose/etiologia , Diferenciação Celular , Células da Medula Óssea/metabolismo
7.
Biomacromolecules ; 24(11): 5105-5115, 2023 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-37800273

RESUMO

The reluctance of a polyester with high glass transition temperature (Tg) and mechanical properties to hydrolyze is a well-known fact, for instance, the high hydrolysis resistance of aromatic polyesters based on terephthalic acid and 2,5-furandicarboxylic acid (FDCA). The synthesis of polyesters that have a high Tg (>100 °C) and a fast hydrolytic degradation quality at the same time is a valuable topic. Herein, a renewable rigid diester, N,N'-trans-1,4-cyclohexane-bis(pyrrolidone-4-methyl carboxylate) (CBPC), was obtained via Michael addition. CBPC was copolymerized with FDCA and ethylene glycol to prepare a series of copolyesters PECxEFy with a high Mn over 30 kDa. PECxEFy showed a Tg range of 75.2-109.2 °C which outdistanced the most biobased polyesters. The thermal stability of all PECxEFy remained unchanged with the introduction of CBPC. Moreover, PECxEFy presented superior mechanical performances which were matching or exceeding those of commercial polyethylene terephthalate (PET) and polylactic acid (PLA). PECxEFy was stable in air but was able to undergo noticeable hydrolytic degradation, proving their enhanced degradability. And the regulation between CBPC and FDCA composition can be leveraged to adjust the degradation and environmental durability of PECxEFy, up to practical applications. Computational studies systematically revealed the relationship between CBPC with a tricyclic structure and the improved Tg and hydrolyzation properties. The outstanding thermal and mechanical performances and hydrolysis of these copolyesters appear to be promising candidates for renewable alternatives to industrial petrochemical polyesters.


Assuntos
Ácidos Dicarboxílicos , Poliésteres , Temperatura de Transição , Hidrólise , Poliésteres/química , Ácidos Dicarboxílicos/química
8.
ACS Appl Mater Interfaces ; 15(38): 45516-45525, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37722024

RESUMO

Applying external vibrations at the resonant frequencies of the frictional system has been a highly effective approach to suppress friction but usually requires additional energy consumption. In this study, we find that in addition to exerting the vibration at the resonant frequency of the frictional system, the friction force on the atomically flat silicon surface can also present a local minimum when the oscillation frequency of the vertical vibrational excitation equals the washboard frequency with respect to the sliding velocity. Moreover, compared with the additional energy consumption at the resonant frequency, applying vertical vibrational excitation at the washboard frequency requires much less energy consumption. The study further shows that the friction force under the washboard frequency can be effectively mediated depending on how the initial phase angle of the vertical vibrational excitation affects the effective substrate potential barrier at the slip moment of the tip. We have also extended the proposed friction modulation technique on atomically flat surfaces to periodic textured surfaces and confirmed its practicality and great potential for controlling friction.

9.
Front Oncol ; 13: 1220435, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37409253

RESUMO

Objective: The purpose of this study was to analyze the trends by year, country, institution, journal, reference and keyword in publications on the autophagy of pancreatic cancer (PC) and to predict future research hotspots. Methods: The Web of Science Core Collection was used to search for publications. The contributions of various countries/regions, institutes, authors, identified research hotspots, and promising future trends were analyzed using the VOSviewer1.6.16 and CiteSpace6.6.R2 programs. We also summarized autophagy relevant clinical trials of PC. Results: A total of 1293 papers on the autophagy of PC published between 2013 and 2023 were included in the study. The average number of citations per article was 33.76. The China had the most publications, followed by USA, and a total of 50 influential articles were identified through co-citation analysis. Clustering analysis revealed clusters of keywords: metabolic reprogramming and ER stress, mTOR-mediated apoptosis, extracellular trap as the most concerned clusters. The co-occurrence cluster analysis showed pancreatic stellate cell, autophagy-dependent ferroptosis, autophagy-related pathway, metabolic rewiring, on-coding RNA as the highly concerned research topics in recently. Conclusion: The number of publications and research interest have generally increased over the past few years. The China and USA have made prominent contributions to the study of the autophagy of PC. The current research hotspots mainly focus not only on the related modulation, metabolic reprogramming, ferroptosis of tumor cells themselves, but also on tumor microenvironments such as autophagy associated pancreatic stellate cells and new treatments targeting autophagy.

10.
Macromol Rapid Commun ; 44(19): e2300263, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37435986

RESUMO

Non-isocyanate polyurethanes (NIPUs) are widely studied as sustainability potential, because they can be prepared without using toxic isocyanates in the synthesis process. The aminolysis of cyclic carbonate to form NIPUs is a promising route. In this work, a series of NIPUs is prepared from renewable bis(6-membered cyclic carbonates) (iEbcc) and amines. The resulting NIPUs possess excellent mechanical properties and thermal stability. The NIPUs can be remolded via transcarbamoylation reactions, and iEbcc-TAEA-10 (the molar ratio of tris(2-aminoethyl)amine in amines is 10%) still get a recovery ratio of 90% in tensile stress after three cycles of remolding. In addition, the obtained materials can be chemically degraded into bi(1,3-diol) precursors with high purity (>99%) and yield (>90%) through alcoholysis. Meanwhile, the degraded products can be used to regenerate NIPUs with similar structures and properties as the original samples. The synthetic strategy, isocyanate-free and employing isoeugenol and carbon dioxide (CO2 ) as building blocks, makes this approach an attractive pathway to NIPU networks taking a step toward a circular economy.

11.
Front Plant Sci ; 14: 1124046, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36760645

RESUMO

Vitis adenoclada is a wild grape unique to China. It exhibits well resistance to heat, humidity, fungal disease, drought, and soil infertility. Here, we report the high-quality, chromosome-level genome assembly of GH6 (V. adenoclada). The 498.27 Mb genome contained 221.78 Mb of transposable elements, 28,660 protein-coding genes, and 481.44 Mb of sequences associated with 19 chromosomes. GH6 shares a common ancestor with PN40024 (Vitis vinifera) from approximately 4.26-9.01 million years ago, whose divergence occurred later than Vitis rotundifolia and Vitis riparia. Widely-targeted metabolome and transcriptome analysis revealed that the profiles and metabolism of phenolic compounds in V. adenoclada varieties significantly were differed from other grape varieties. Specifically, V. adenoclada varieties were rich in phenolic acids and flavonols, whereas the flavan-3-ol and anthocyanin content was lower compared with other varieties that have V. vinifera consanguinity in this study. In addition, ferulic acid and stilbenes content were associated with higher expressions of COMT and STSs in V. adenoclada varieties. Furthermore, MYB2, MYB73-1, and MYB73-2 were presumably responsible for the high expression level of COMT in V. adenoclada berries. MYB12 (MYBF1) was positively correlated with PAL, CHS, FLS and UFGT.Meanwhile, MYB4 and MYBC2-L1 may inhibit the synthesis of flavan-3-ols and anthocyanins in two V. adenoclada varieties (YN2 and GH6). The publication of the V. adenoclada grape genome provides a molecular foundation for further revealing its flavor and quality characteristics, is also important for identifying favorable genes of the East Asian species for future breeding.

12.
ACS Appl Mater Interfaces ; 15(1): 2246-2255, 2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36563296

RESUMO

In the current context of sustainable chemistry development and new regulations, aminolysis of cyclic carbonate is one of the most promising routes to nonisocyanate polyurethanes, also called polyhydroxyurethanes (PHU). In this study, a new kind of shape memory PHU vitrimers with outstanding mechanical properties and chemical recyclability is prepared. The monomer employed for aminolysis to form the PHUs is bis(six-membered cyclic carbonate) of 4,4'-biphenol (BCC-BP), which is synthesized by bi(1,3-diol) precursors and CO2. The synthetic strategy, isocyanate-free and employing CO2 as a building block, is environmentally friendly and suits the concept of carbon neutrality. The thermal properties, mechanical properties, and dynamic behaviors of the PHUs are explored. The maximum breaking strength and elongation at break of the resultant PHUs reach 65 MPa and 452%, respectively, exceeding other reported PHU-based materials in combined performance. Such a PHU material can also lift up a load 4700 times heavier than its own weight by a shape recovery process. Finally, the bi(1,3-diol) can be regenerated through the alcoholysis of PHUs to realize chemical recycling. This work provides a feasibility study for a green synthetic approach and for designing a novel PHU material with outstanding properties.

13.
Int J Biol Macromol ; 225: 1599-1606, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36427622

RESUMO

Adding nucleating agents has been a successful strategy to boost the heat resistance of poly(L-lactic acid) (PLLA) by increasing the crystallinity. In this study, a new series of bio-based complexes as nucleating agents for PLLA, including twelve combinations of three eco-friendly metal ions (Zn, Mg, Ca) and four biomass-derived α-hydroxy acids, were successfully synthesized to respectively investigate the effects of metal ions as well as ligands on nucleation capacity of complexes. By investigating the non-isothermal and isothermal crystallization at 135 °C of PLLA with 0.3 wt% loading of complexes, both zinc and magnesium salts of L-mandelic acid showed excellent nucleation capacities. And magnesium L-mandelate performed better, raising the crystallinity of PLLA to 44.4 % as well as minimizing its crystallization half-time from 73 min to 2.7 min. The growth and denser distribution of PLLA spherulites on the salt surface were also observed by POM, reflecting epitaxial nucleation as the possible mechanism. A novel inspiration, utilizing VESTA software to simulate the crystal structure of zinc L-mandelate (Zn(L-MA)2), was proposed to determine the nucleation mechanism. Also, using polyethylene terephthalate (PET) as a test protocol, the rationality of the model could be approved by checking the fitness of nucleating prediction and experiment results.


Assuntos
Polímeros , Sais , Polímeros/química , Magnésio , Biomassa , Ácido Láctico/química , Polietilenotereftalatos , Zinco
14.
Front Microbiol ; 13: 1051364, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36439789

RESUMO

Objective: Acinetobacter baumannii is one of the most important pathogenic bacteria causing nosocomial infections and has a high mortality rate. Assessment of the microbiological characteristics and risk factors on prognosis associated with A.baumannii is essential. In this study, we aimed to investigate the clinical characteristics and prognostic risk factors of patients with A.baumannii bacteremia. Patients and Methods: This study retrospectively analyzed the antibiotic resistance of pathogens based on the clinical data of A.baumannii bacteremia patients presented in a tertiary teaching hospital from 2017 to 2022. Logistic regression and decision tree identified the prognostic risk factors for patients with baumannemia. Kaplan-Meier method was used for survival analysis between MDR and Non-MDR groups. The area under receiver-operating characteristic curve (ROC curve) was used to compare the predictive value of the APACHE II score and Sequential Organ Failure Assessment (SOFA) score. Results: A total of 110 patients with positive A. Baumannii blood cultures were included. Most of the patients were from intensive care unit (ICU) wards. The drug sensitivity results showed that the resistance rate of A. baumannii to colistin was the lowest (1.1%), followed by tigecycline (3.6%).The survival time of MDR group was significantly shorter than that of Non-MDR group. Multivariate analysis showed that, APACHE II score and SOFA score were independent risk factors affecting the prognosis of 28 days of A.baumannii bacteremia. And both scores displayed excellent AUROCs (SOFA: 0.909, APACHE II: 0.895 in predicting 28-day mortality). The two scoring systems were highly correlated and predicted no significant difference (r 2 = 0.4410, P < 0.001). We found that SOFA > 7 and APACHE II > 21 are associated with significantly higher mortality rates. Conclusion: A.baumannii bacteremia have the highest incidence in the ICU, with high drug resistance and mortality rates. The survival time of patients with MDR A. Baumannii bacteremia was significantly shortened. The SOFA score and APACHE II score can reflect the severity of A.baumannii bacteremia patients and evaluate the 28-day prognosis. In addition, for the convenience of calculation, the SOFA score may be more clinically useful than the APACHE II score in predicting the mortality rate of A.baumannii bacteremia.

15.
Transl Cancer Res ; 11(9): 3421-3425, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36237249

RESUMO

Background: Endometrial stromal sarcoma (ESS) is a uterine stromal tumor with a very low incidence, accounting for 10-15% of all uterine stromal malignancies and 0.2% of all uterine malignancies. The most common extrauterine location of ESS is the ovary, and it is relatively rare outside the uterus. Although most recurrences occur within the pelvis, distant metastases can occur. Case Description: We report a rare case of low-grade ESS (LG-ESS) metastatic to the inferior vena cava (IVC) which is difficult to distinguish from leiomyoma clinically. A 56-year-old woman attended outpatient complaining right thigh pain. She underwent a surgery of hysterectomy and bilateral adnexectomy 12 years ago. Abdominal contrast-enhanced computed tomography (CT) demonstrated that the vaginal stump was thick, with peripheral multiple nodular shadow. Soft tissue shadow in the right pelvic cavity. Thickening and enhancement of soft tissue shadow were observed in the peripheral blood vessels of the vaginal stump, the right internal iliac vein and the external iliac vein to the IVC of the liver segment. Malignancy (recurrence or metastasis) were considered. After multidisciplinary consultant, a preoperative diagnosis of leiomyomatosis of the IVC was made and surgical treatment was performed. Surgeons performed laparotomy, resection of tumor in IVC, right common iliac vein, right external iliac vein, right internal iliac vein and left common iliac vein. Post-operative pathology of dissected tumor demonstrated LG-ESS. The source may be the ovarian venous stump left after surgery 12 years ago. After a gynecological consultant, chemotherapy is recommended and is currently under follow-up. Conclusions: We report a rare case of LG-ESS metastatic to the IVC, which was probably a lesion derived from the ovarian venous stump remaining after surgery 12 years ago.

16.
Micromachines (Basel) ; 13(7)2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35888961

RESUMO

The assessment of the biodegradability of nanomaterials is of pragmatic importance for understanding the interactions between nanomaterials and biological systems and for the determination of ultimate fate of these materials as well as their potential use. We recently developed carbon-based biconcave nanodisks (CBBNs) serving as a versatile nanocarrier for enhanced accumulation in tumors and combined photothermal-chemotherapy. Here, we investigate both the enzymatic and cellular degradation of CBBNs by monitoring their cellular response with electron microscopy, near-infrared absorbance spectroscopy, and cell viability and oxidative stress assessments. Our results show that CBBNs underwent significant degradation in solutions catalyzed by horseradish peroxidase (HRP) and hydrogen peroxide (H2O2), or in the presence of macrophage cells. The ability of CBBNs to be degraded in biological systems provides suitability for their future biomedical applications.

17.
Biomacromolecules ; 23(4): 1733-1744, 2022 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-35107271

RESUMO

The lack of selectivity between tumor and healthy cells, along with inefficient reactive oxygen species production in solid tumors, are two major impediments to the development of anticancer Ru complexes. The development of photoinduced combination therapy based on biodegradable polymers that can be light activated in the "therapeutic window" would be beneficial for enhancing the therapeutic efficacy of Ru complexes. Herein, a biodegradable Ru-containing polymer (poly(DCARu)) is developed, in which two different therapeutics (the drug and the Ru complex) are rationally integrated and then conjugated to a diblock copolymer (MPEG-b-PMCC) containing hydrophilic poly(ethylene glycol) and cyano-functionalized polycarbonate with good degradability and biocompatibility. The polymer self-assembles into micelles with high drug loading capacity, which can be efficiently internalized into tumor cells. Red light induces the generation of singlet oxygen and the release of anticancer drug-Ru complex conjugates from poly(DCARu) micelles, hence inhibiting tumor cell growth. Furthermore, the phototherapy of polymer micelles demonstrates remarkable inhibition of tumor growth in vivo. Meanwhile, polymer micelles exhibit good biocompatibility with blood and healthy tissues, which opens up opportunities for multitherapeutic agent delivery and enhanced phototherapy.


Assuntos
Antineoplásicos , Neoplasias , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Portadores de Fármacos , Humanos , Micelas , Neoplasias/tratamento farmacológico , Fototerapia , Cimento de Policarboxilato , Polietilenoglicóis/uso terapêutico , Polímeros
18.
Front Immunol ; 13: 1060612, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36591259

RESUMO

Background: The maintenance of blood pressure is pivotal in preventing sepsis with acute kidney injury (AKI). Especially in sepsis patients treated with vasopressors. The optimal the blood pressure has been controversial to maintain renal perfusion. This study aims to explore the blood pressure target in sepsis with AKI. Methods: We retrieved patient data from the MIMIC IV and eICU databases. The Lasso regression model was used to identify the relationship between blood pressure and sepsis in patients with AKI and remove collinearity among variables. Generalized additive models were used to estimate the blood pressure range in patients with sepsis with AKI. Statistical methods such as multivariable logistic regression, propensity score analysis, inversion probability-weighting, and doubly robust model estimation were used to verify the target blood pressure for patients with sepsis and AKI. Results: In total, 17874 patients with sepsis were included in this study. the incidence of AKI may be related to the level of mean article pressure (MAP) and diastolic blood pressure (DBP) in sepsis patients. The range of MAPs and DBPs may be 65-73 mmHg and 50-60 mmHg in AKI patients without hypertension. The range of MAPs and DBPs may be 70-80 mmHg and 54-62 mmHg in AKI patients with hypertension. The prognosis of sepsis with AKI was unaffected by MAP or DBP. Systolic blood pressure is not associated with sepsis in patients with AKI. Conclusions: To ensure renal perfusion, AKI patients with hypertension may require a higher MAP [70-80] versus (65-73), mmHg] and DBP [(54-62) vs (50-60), mmHg] than patients without hypertension.


Assuntos
Injúria Renal Aguda , Hipertensão , Sepse , Humanos , Pressão Sanguínea , Sepse/complicações , Estudos de Coortes , Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/etiologia , Hipertensão/complicações
19.
Polymers (Basel) ; 13(21)2021 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-34771313

RESUMO

Biodegradable polymers have been rapidly developed for alleviating excessive consumption of non-degradable plastics. Additive manufacturing is also a green energy-efficiency and environment-protection technique to fabricate complicated structures. Herein, biodegradable polyesters, polyglycolic acid (PGA) and poly (butyleneadipate-co-terephthalate) (PBAT) were blended and developed into feedstock for 3D printing. Under a set of formulations, PGA/PBAT blends exhibited a tailored stiffness-toughness mechanical performance. Then, PGA/PBAT (85/15 in weight ratio) with good thermal stability and mechanical property were extruded into filaments with a uniform wire diameter. Mechanical testing clearly indicated that FDM 3D-printed exhibited comparable tensile, flexural and impact properties with injection-molded samples of PGA/PBAT (85/15). Furthermore, uniform and graded Diamond-Triply Periodic Minimal Surfaces (D-TPMS) structures were designed and successfully manufactured via the fused deposition modeling (FDM) technique. Computer tomography (CT) was employed to confirm the internal three-dimensional structures. The compressive test results showed that PGA/PBAT (85/15) D-surface structures bear better load-carrying capacity than that of neat PGA, giving an advantage of energy absorption. Additionally, typical industrial parts were manufactured with excellent dimension-stability, no-wrapping and fine quality. Collectively, biodegradable PGA/PBAT material with good printability has great potentials in application requiring stiffer structures.

20.
Adv Sci (Weinh) ; 8(23): e2103334, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34664422

RESUMO

The synergistic combination of chemotherapy and photodynamic therapy has attracted considerable attention for its enhanced antitumoral effects; however, it remains challenging to successfully delivery photosensitizers and anticancer drugs while minimizing drug leakage at off-target sites. A red-light-activatable metallopolymer, Poly(Ru/PTX), is synthesized for combined chemo-photodynamic therapy. The polymer has a biodegradable backbone that contains a photosensitizer Ru complex and the anticancer drug paclitaxel (PTX) via a singlet oxygen (1 O2 ) cleavable linker. The polymer self-assembles into nanoparticles, which can efficiently accumulate at the tumor sites during blood circulation. The distribution of the therapeutic agents is synchronized because the Ru complex and PTX are covalently conjugate to the polymer, and off-target toxicity during circulation is also mostly avoided. Red light irradiation at the tumor directly cleaves the Ru complex and produces 1 O2 for photodynamic therapy. Sequentially, the generated 1 O2 triggers the breakage of the linker to release the PTX for chemotherapy. Therefore, this novel sequential dual-model release strategy creates a synergistic chemo-photodynamic therapy while minimizing drug leakage. This study offers a new platform to develop smart delivery systems for the on-demand release of therapeutic agents in vivo.

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