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2.
J Control Release ; 372: 810-828, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38968969

RESUMEN

Cancer is a serious threat to human health because of its high annual mortality rate. It has attracted significant attention in healthcare, and identifying effective strategies for the treatment and relief of cancer pain requires urgency. Drug delivery systems (DDSs) offer the advantages of excellent efficacy, low cost, and low toxicity for targeting drugs to tumor sites. In recent decades, copolymer carriers based on poly(phenylalanine) (PPhe) and poly(3,4-dihydroxy-L-phenylalanine) (PDopa) have been extensively investigated owing to their good biocompatibility, biodegradability, and controllable stimulus responsiveness, which have resulted in DDSs with loading and targeted delivery capabilities. In this review, we introduce the synthesis of PPhe and PDopa, highlighting the latest proposed synthetic routes and comparing the differences in drug delivery between PPhe and PDopa. Subsequently, we summarize the various applications of PPhe and PDopa in nanoscale-targeted DDSs, providing a comprehensive analysis of the drug release behavior based on different stimulus-responsive carriers using these two materials. In the end, we discuss the challenges and prospects of polypeptide-based DDSs in the field of cancer therapy, aiming to promote their further development to meet the growing demands for treatment.


Asunto(s)
Portadores de Fármacos , Humanos , Portadores de Fármacos/química , Animales , Sistemas de Liberación de Medicamentos , Péptidos/química , Péptidos/administración & dosificación , Nanopartículas/química , Neoplasias/tratamiento farmacológico , Polímeros/química , Liberación de Fármacos , Fenilalanina/química , Fenilalanina/administración & dosificación , Antineoplásicos/administración & dosificación , Antineoplásicos/química , Materiales Biocompatibles/química
3.
Molecules ; 29(13)2024 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-38998932

RESUMEN

Microbial contamination has profoundly impacted human health, and the effective eradication of widespread microbial issues is essential for addressing serious hygiene concerns. Taking polystyrene (PS) membrane as an example, we herein developed report a robust strategy for the in situ preparation of chlorine-regenerable antimicrobial polymer molecular sieve membranes through combining post-crosslinking and nucleophilic substitution reaction. The cross-linking PS membranes underwent a reaction with 5,5-dimethylhydantoin (DMH), leading to the formation of polymeric N-halamine precursors (PS-DMH). These hydantoinyl groups within PS-DMH were then efficiently converted into biocidal N-halamine structures (PS-DMH-Cl) via a simple chlorination process. ATR-FTIR and XPS spectra were recorded to confirm the chemical composition of the as-prepared PS-DMH-Cl membranes. SEM analyses revealed that the chlorinated PS-DMH-Cl membranes displayed a rough surface with a multitude of humps. The effect of chlorination temperature and time on the oxidative chlorine content in the PS-DMH-Cl membranes was systematically studied. The antimicrobial assays demonstrated that the PS-DMH-Cl membranes could achieve a 6-log inactivation of E. coli and S. aureus within just 4 min of contact time. Additionally, the resulting PS-DMH-Cl membranes exhibited excellent stability and regenerability of the oxidative chlorine content.


Asunto(s)
Cloro , Escherichia coli , Membranas Artificiales , Staphylococcus aureus , Cloro/química , Escherichia coli/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Antiinfecciosos/farmacología , Antiinfecciosos/química , Halogenación , Polímeros/química , Poliestirenos/química , Hidantoínas/química , Hidantoínas/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Aminas
4.
Langmuir ; 40(32): 16670-16689, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-38913990

RESUMEN

Waste polystyrene contributes considerably to environmental pollution due to its persistent nature, prompting a widespread consensus on the urgent need for viable recycling solutions. Owing to the aromatic groups structure of polystyrene, hyper-cross-linked polymers can be synthesized through the Friedel-Crafts cross-linking reaction using Lewis acids as catalysts. In addition, hyper-cross-linked polystyrene and its carbonaceous counterparts can be used in several important applications, which helps in their efficient recycling. This review systematically explores methods for preparing multifunctional hyper-cross-linked polymers from waste polystyrene and their applications in sustainable recycling. We have comprehensively outlined various synthetic approaches for these polymers and investigated their physical and chemical properties. These multifunctional polymers not only exhibit structural flexibility but also demonstrate diversity in performance, making them suitable for various applications. Through a systematic examination of synthetic methods, we showcase the cutting-edge positions of these materials in the field of hyper-cross-linked polymers. Additionally, we provide in-depth insights into the potential applications of these hyper-cross-linked polymers in intentional recycling, highlighting their important contributions to environmental protection and sustainable development. This research provides valuable references to the fields of sustainable materials science and waste management, encouraging further exploration of innovative approaches for the utilization of discarded polystyrene.

5.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 36(4): 353-357, 2024 Apr.
Artículo en Chino | MEDLINE | ID: mdl-38813627

RESUMEN

OBJECTIVE: To investigate the predictive value of left ventricular global longitudinal peak strain (GLPS) for the prognosis of septic patients. METHODS: A prospective cohort study was conducted. Patients diagnosed with sepsis and admitted to the intensive care unit (ICU) of the First Affiliated Hospital, Sun Yat-sen University from December 2018 to November 2019 were enrolled. The patient characteristics, cardiac ultrasound parameters [left ventricular ejection fraction (LVEF), right ventricular ejection fraction (RVEF), four-dimensional ejection fraction (4DEF), GLPS] and cardiac biomarkers [N-terminal pro-brain natriuretic peptide (NT-proBNP), cardiac troponin T (cTnT)] within 24 hours of ICU admission, organ support therapies, severity of illness, and prognostic indicators were documented. The differences in clinical parameters between patients with varying outcomes during ICU hospitalization were assessed. Pearson correlation analysis was employed to explore the correlation between GLPS and other cardiac systolic parameters, as well as the associations between various cardiac systolic parameters and sequential organ failure assessment (SOFA) score. Receiver operator characteristic curve (ROC curve) was drawn to analyze the predictive capacity of cardiac ultrasound parameters and cardiac biomarkers for death during ICU hospitalization in septic patients. RESULTS: A total of 50 septic patients were enrolled, with 40 surviving and 10 dying during ICU hospitalization, resulting in a mortality of 20.0%. All patients in the death group were male. Compared with the survival group, the patients in the death group were older, had a higher prevalence of diabetes mellitus, and received continuous renal replacement therapy (CRRT) more frequently, additionally, they exhibited more severe illness and had longer length of ICU stay. The levels of GLPS and cTnT in the death group were significantly elevated as compared with the survival group [GLPS: -7.1% (-8.5%, -7.0%) vs. -12.1% (-15.5%, -10.4%), cTnT (µg/L): 0.07 (0.05, 0.08) vs. 0.03 (0.02, 0.13), both P < 0.05]. However, no statistically significant difference was found in other cardiac ultrasound parameters or cardiac biomarkers between the two groups. Pearson correlation analysis revealed a negative correlation between GLPS and LVEF (r = -0.377, P = 0.014) and 4DEF (r = -0.697, P = 0.000), while no correlation was found with RVEF (r = -0.451, P = 0.069). GLPS demonstrated a positive correlation with SOFA score (r = 0.306, P = 0.033), while LVEF (r = 0.112, P = 0.481), RVEF (r = -0.134, P = 0.595), and 4DEF (r = -0.251, P = 0.259) showed no significant correlation with SOFA score. ROC curve analysis indicated that the area under the ROC curve (AUC) of GLPS for predicting death during ICU hospitalization in septic patients was higher than other cardiac systolic parameters, including LVEF, RVEF, and 4DEF, as well as cardiac biomarkers NT-proBNP and cTnT (0.737 vs. 0.628, 0.556, 0.659, 0.580 and 0.724). With an optimal cut-off value of -14.9% for GLPS, the sensitivity and negative predictive value reached to 100%. CONCLUSIONS: GLPS < -14.9% within 24 hours of ICU admission in septic patients indicated a reduced risk of death risk during ICU hospitalization, while also correlating with the severity of organ dysfunction in this patient population.


Asunto(s)
Unidades de Cuidados Intensivos , Sepsis , Humanos , Estudios Prospectivos , Pronóstico , Sepsis/diagnóstico , Sepsis/mortalidad , Sepsis/fisiopatología , Troponina T/sangre , Ventrículos Cardíacos/fisiopatología , Ventrículos Cardíacos/diagnóstico por imagen , Biomarcadores/sangre , Ecocardiografía , Función Ventricular Izquierda , Volumen Sistólico , Masculino , Femenino , Péptido Natriurético Encefálico/sangre , Curva ROC , Fragmentos de Péptidos/sangre , Valor Predictivo de las Pruebas , Persona de Mediana Edad
6.
Adv Sci (Weinh) ; 11(19): e2308668, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38477515

RESUMEN

Vanadium nitride (VN) is a potential cathode material with high capacity and high energy density for aqueous zinc batteries (AZIBs). However, the slow kinetics resulting from the strong electrostatic interaction of the electrode materials with zinc ions is a major challenge for fast storage. Here, VN clusters with nitrogen-vacancy embedded in carbon (C) (Nv-VN/C-SS-2) are prepared for the first time to improve the slow reaction kinetics. The nitrogen vacancies can effectively accelerate the reaction kinetics, reduce the electrochemical polarization, and improve the performance. The density functional theory (DFT) calculations also prove that the rapid adsorption and desorption of zinc ions on Nv-VN/C-SS-2 can release more electrons to the delocalized electron cloud of the material, thus adding more active sites. The Nv-VN/C-SS-2 exhibits a specific capacity and outstanding cycle life. Meanwhile, the quasi-solid-state battery exhibits a high capacity of 186.5 mAh g-1, ultra-high energy density of 278.9 Wh kg-1, and a high power density of 2375.1 W kg-1 at 2.5 A g-1, showing excellent electrochemical performance. This work provides a meaningful reference value for improving the comprehensive electrochemical performance of VN through interface engineering.

7.
J Mater Chem B ; 12(8): 2054-2069, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38305698

RESUMEN

Microporous organic polymers (MOPs) and metal oxide hybrid composites are considered valuable coating materials because of their versatility derived from the synergistic combination of MOPs' inherent dispersibility and the distinctive properties of metal oxides. In this study, we present the synthesis of sea-urchin-like MOPs hybridised with silver oxide nanoparticles (Ag2O NPs) to fabricate antibacterial composites suitable for potential antibacterial coating applications. Ag2O NP-decorated urchin-like MOPs (Ag2O@UMOPs) were synthesised by employing a combination of two methods: a one-pot Lewis acid-base interaction-mediated self-assembly and a straightforward impregnation process. The as-prepared Ag2O@UMOPs demonstrated high antibacterial efficacy against both E. coli (G-) and S. aureus (G+). The antibacterial mechanism of Ag2O@UMOPs mainly involved the synergistic effects of accumulation of Ag2O@UMOPs, the release of Ag+ ions, and the generation of reactive oxygen species. The exceptional processability and biosafety of Ag2O@UMOPs make them ideal organic coating materials for convenient application on various substrates. These remarkable features of Ag2O@UMOPs provide an effective platform for potential antibacterial applications in biological sciences.


Asunto(s)
Escherichia coli , Compuestos de Plata , Staphylococcus aureus , Óxidos/química , Antibacterianos/farmacología , Antibacterianos/química
8.
FASEB J ; 37(8): e23063, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37401890

RESUMEN

Sepsis-induced myocardial depression (SIMD) is common in pediatric intensive care units and seriously threatens children's health. Recently, long noncoding RNAs (lncRNAs) have been showed to play important roles in various diseases; however, its role in SIMD is unclear. In this study, we used lipopolysaccharide (LPS)-treated rats and H9c2 cardiomyocytes to mimic SIMD in vivo and in vitro. We found that the expression of a novel lncRNA, we named lncRNA-AABR07066529.3, was elevated in LPS-induced rat heart tissue and H9c2 cardiomyocytes. In addition, LPS-induced inflammation, apoptosis, and pyroptosis were significantly exacerbated after lncRNA-AABR07066529.3 knockdown. Moreover, we found that myeloid differentiation factor 88 (MyD88) was upregulated in LPS-treated groups and was inhibited by lncRNA-AABR07066529.3. Besides, MyD88 knockdown abolished lncRNA-AABR07066529.3 silencing effects on inflammation, apoptosis, and pyroptosis induced by LPS in H9c2 cardiomyocytes. In our study, we found lncRNA-AABR07066529.3 exerted protective effects on LPS-induced cardiomyocytes by regulating MyD88 and might serve as a potential treatment target for SIMD.


Asunto(s)
Cardiomiopatías , MicroARNs , ARN Largo no Codificante , Animales , Ratas , Apoptosis , Cardiomiopatías/metabolismo , Depresión , Inflamación/inducido químicamente , Inflamación/genética , Inflamación/metabolismo , Lipopolisacáridos/farmacología , MicroARNs/genética , Factor 88 de Diferenciación Mieloide/genética , Factor 88 de Diferenciación Mieloide/metabolismo , Miocitos Cardíacos/metabolismo , Piroptosis/genética , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo
9.
Front Cell Infect Microbiol ; 13: 1173362, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37249974

RESUMEN

Background: Children with influenza B virus infection have a higher susceptibility and higher severity of illness. The activation and disorder of immune function play an important role in the severity of influenza virus infection. This study aims to investigate whether early lymphocyte count and cytokines can provide predictive value for the progression in children with influenza B virus pneumonia. Methods: A retrospective cohort study was conducted to analyze the clinical data of children with influenza B virus pneumonia from December 1, 2021, to March 31, 2022, in the National Children's Regional Medical Center (Shengjing Hospital of China Medical University). According to the severity of the disease, the children were divided into a mild group and a severe group, and the clinical characteristics, routine laboratory examination, lymphocyte subsets, and cytokines were compared. Results: A total of 93 children with influenza B virus pneumonia were enrolled, including 70 cases in the mild group and 23 cases in the severe group. Univariate analysis showed that drowsiness, dyspnea, white blood cell (WBC), lymphocytes, monocytes, procalcitonin, alanine aminotransferase (ALT), aspartate aminotransferase (AST), creatine kinase-MB (CK-MB), lactate dehydrogenase (LDH), fibrinogen (FIB), Immunoglobulin M (IgM), lung consolidation, total T cell count, CD4+ T cell count, CD8+ T cell count, NK cell count, NK cell % and B cell % had statistical differences between the mild and severe groups (P<0.05). In multivariate logistic regression analysis, reduced ALT (OR = 1.016), FIB (OR = 0.233), CD8+ T cell count (OR = 0.993) and NK cell count (OR = 0.987) were independently associated with the development of severe influenza B virus pneumonia. Conclusions: The levels of T lymphocytes and NK cells were related to the progression of influenza B virus pneumonia in children, and the reduction of CD8+ T cell count and NK cell count can be used as independent risk factors for predicting the severity of influenza B virus pneumonia.


Asunto(s)
Gripe Humana , Neumonía , Humanos , Niño , Citocinas , Virus de la Influenza B , Gripe Humana/diagnóstico , Estudios Retrospectivos , Neumonía/diagnóstico , Subgrupos Linfocitarios , Recuento de Linfocitos
10.
Front Pediatr ; 11: 997163, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37056947

RESUMEN

Background: We studied the causative pathogens, clinical characteristics, and outcome of bacterial meningitis in children with an abnormal craniocerebral structure. Methods: A retrospective single-center study was conducted on children aged in the range of 29 days to 14 years by using data obtained from the pediatric intensive care unit in Shengjing Hospital between January 2014 and August 2021. All children were diagnosed with bacterial meningitis. They were divided into complex and simple groups by taking into account the presence of an abnormal craniocerebral structure before they contracted bacterial meningitis. We collected data on demographics, clinical presentations, laboratory results, imaging studies, treatments, and outcomes. Results: A total of 207 patients were included in the study (46 in the complex group and 161 in the simple group). Patients in the complex group had a lower mortality rate (6.5% vs. 11.2%, p < 0.05), positive blood culture (13.0% vs. 34.8%; p < 0.05), multiple organ dysfunction syndrome (0% vs. 9.3%; p < 0.05), and shock (2.2% vs. 9.3%; p = 0.11). These patients were more often detected with neurological sequelae (80.4% vs. 53.4%; p < 0.05), cerebrospinal fluid drainage (50% vs. 15.5%; p < 0.05), nosocomial infection (54.3% vs. 3.1%; p < 0.05), and multidrug-resistant bacteria (62.5% vs. 55.6%, p = 0.501). In patients in the simple group, infection was mostly confined to the nervous system. Conclusion: Bacterial meningitis patients with an abnormal craniocerebral structure had fewer bloodstream infections, lower mortality rates, and higher incidence rates of neurological sequelae. Pathogens were more likely to be nosocomial and multidrug-resistant bacteria.

11.
Chem Commun (Camb) ; 59(32): 4794-4797, 2023 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-37000566

RESUMEN

A metal-organic framework (MOF) is used to thermally grow cobalt selenophosphide (CoSeP) nanoparticles on an N-doped 2-dimensional carbon matrix (CoSeP@N-C), resulting in an assembled unique 3-dimensional bean sprout-like nanosheet composite with massive defects as an advanced anode material of sodium ion batteries. The results indicate that the massive defects in the CoSeP@N-C sprout-like 3-D structure can offer high density of reaction sites and well accommodate the volume change during the sodiation/desodiation process, while rendering abundant channels for rapid transport of sodium ions, thereby synergistically making the CoSeP@N-C anode much more reversible for the sodium ion storage process and producing higher rate performance than those of CoP2 and CoSe2@N-C. The ex situ X-ray diffraction, ex situ Raman and ex situ TEM analyses further confirm the mechanism of sodium storage intercalation and transformation in CoSeP@N-C. This work vividly demonstrates a rational design of metal selenophosphide anodes as an effective strategy to accomplish fast and high sodium-ion storage.

13.
Behav Sci (Basel) ; 13(2)2023 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-36829356

RESUMEN

Students' behaviors have a close relationship with their learning efficiencies, particularly about professional knowledge. Different types of behaviors should have different influences. Disclosing the special relationship between undergraduate students' conscious safety behaviors in their laboratory experiments with their learning efficiencies is important for fostering them into professional talents. In this study, a course entitled "Advanced Methods of Materials Characterization" was arranged to contain three sections: theoretical learning in the classroom, eight characterization experiments in the laboratory in sequence, and self-training to apply the knowledge. In the final examination, eighteen percent was allocated to the examination questions about safety issues. The students' scores for this section were associated with their total roll scores. Two quantitative relationships are disclosed. One is between the students' final examination score (y) and their subjective consciousness of safety behaviors (x) in their laboratory experiments, as y = 5.56 + 4.83 x (R = 0.9192). The other is between their grade point average (y) and safety behavior evaluation (x) as y = 0.51 + 0.15 x (R = 0.7296). Undergraduate students' behaviors in scientific laboratories need to be verified to have a close and positive relationship with their professional knowledge learning efficiencies. This offers a hint that improving students' safety behaviors and enhancing their subjective safety awareness are conducive to improving their learning efficiency for professional knowledge.

14.
Pharmaceutics ; 15(2)2023 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-36839691

RESUMEN

Nanomedicine is a broad field that focuses on the development of nanocarriers to deliver specific drugs to targeted sites. A synthetic polypeptide is a kind of biomaterial composed of repeating amino acid units that are linked by peptide bonds. The multiplied amphiphilicity segment of the polypeptide could assemble to form polypeptide vesicles (PVs) under suitable conditions. Different from polypeptide vesicles, outer membrane vesicles (OMVs) are spherical buds of the outer membrane filled with periplasmic content, which commonly originate from Gram-negative bacteria. Owing to their biodegradability and excellent biocompatibility, both PVs and OMVs have been utilized as carriers in delivering drugs. In this review, we discuss the recent drug delivery research based on PVs and OMVs. These related topics are presented: (1) a brief introduction to the production methods for PVs and OMVs; (2) a thorough explanation of PV- and OMV-related applications in drug delivery including the vesicle design and biological assessment; (3) finally, we conclude with a discussion on perspectives and future challenges related to the drug delivery systems of PVs and OMVs.

15.
Front Med (Lausanne) ; 10: 1337403, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38264034

RESUMEN

Background: Myoglobin is an important biomarker for monitoring critically ill patients. However, the relationship between its dynamic changes and prognosis remains unclear. Methods: We retrospectively enrolled 11,218 critically ill patients from a general and surgical intensive care unit (ICU) of a tertiary hospital between June 2016 and May 2020. Patients with acute cardiovascular events, cardiac and major vascular surgeries, and rhabdomyolysis were excluded. To investigate the early myoglobin distribution, the critically ill patients were stratified according to the highest myoglobin level within 48 h after ICU admission. Based on this, the critically ill patients with more than three measurements within 1 week after ICU admission were included, and latent class trajectory modeling was used to classify the patients. The characteristics and outcomes were compared among groups. Sensitivity analysis was performed to exclude patients who had died within 72 h after ICU admission. Restricted mean survival time regression model based on pseudo values was used to determine the 28-day relative changes in survival time among latent classes. The primary outcome was evaluated with comparison of in-hospital mortality among each Trajectory group, and the secondary outcome was 28-day mortality. Results: Of 6,872 critically ill patients, 3,886 (56.5%) had an elevated myoglobin level (≥150 ng/mL) at admission to ICU, and the in-hospital mortality significantly increased when myoglobin level exceeded 1,000 µg/mL. In LCTM, 2,448 patients were unsupervisedly divided into four groups, including the steady group (n = 1,606, 65.6%), the gradually decreasing group (n = 523, 21.4%), the slowly rising group (n = 272, 11.1%), and the rapidly rising group (n = 47, 1.9%). The rapidly rising group had the largest proportion of sepsis (59.6%), the highest median Sequential Organ Failure Assessment (SOFA) score (10), and the highest in-hospital mortality (74.5%). Sensitivity analysis confirmed that 98.2% of the patients were classified into the same group as in the original model. Compared with the steady group, the rapidly rising group and the slowly rising group were significantly related to the reduction in 28-day survival time (ß = -12.08; 95% CI -15.30 to -8.86; ß = -4.25, 95% CI -5.54 to -2.97, respectively). Conclusion: Elevated myoglobin level is common in critically ill patients admitted to the ICU. Dynamic monitoring of myoglobin levels offers benefit for the prognosis assessment of critically ill patients.

16.
Circulation ; 146(19): 1444-1460, 2022 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-36073366

RESUMEN

BACKGROUND: Proliferation of vascular smooth muscle cells (VSMCs) is a hallmark of arterial diseases, especially in arterial restenosis after angioplasty or stent placement. VSMCs reprogram their metabolism to meet the increased requirements of lipids, proteins, and nucleotides for their proliferation. De novo purine synthesis is one of critical pathways for nucleotide synthesis. However, its role in proliferation of VSMCs in these arterial diseases has not been defined. METHODS: De novo purine synthesis in proliferative VSMCs was evaluated by liquid chromatography-tandem mass spectrometry. The expression of ATIC (5-aminoimidazole-4-carboxamide ribonucleotide formyltransferase/inosine monophosphate cyclohydrolase), the critical bifunctional enzyme in the last 2 steps of the de novo purine synthesis pathway, was assessed in VSMCs of proliferative arterial neointima. Global and VSMC-specific knockout of Atic mice were generated and used for examining the role of ATIC-associated purine metabolism in the formation of arterial neointima and atherosclerotic lesions. RESULTS: In this study, we found that de novo purine synthesis was increased in proliferative VSMCs. Upregulated purine synthesis genes, including ATIC, were observed in the neointima of the injured vessels and atherosclerotic lesions both in mice and humans. Global or specific knockout of Atic in VSMCs inhibited cell proliferation, attenuating the arterial neointima in models of mouse atherosclerosis and arterial restenosis. CONCLUSIONS: These results reveal that de novo purine synthesis plays an important role in VSMC proliferation in arterial disease. These findings suggest that targeting ATIC is a promising therapeutic approach to combat arterial diseases.


Asunto(s)
Aterosclerosis , Transferasas de Hidroximetilo y Formilo , Humanos , Ratones , Animales , Neointima , Purinas , Proliferación Celular , Miocitos del Músculo Liso , Aterosclerosis/genética
17.
Biomolecules ; 12(8)2022 08 12.
Artículo en Inglés | MEDLINE | ID: mdl-36009003

RESUMEN

The purpose of this work is to develop a novel ultrathin fibrous membrane with a core-sheath structure as antibacterial food packaging film. Coaxial electrospinning was exploited to create the core-sheath structure, by which the delivery regulation of the active substance was achieved. Resveratrol (RE) and silver nanoparticles (AgNPs) were loaded into electrospun zein/polyethylene oxide ultrathin fibers to ensure a synergistic antibacterial performance. Under the assessments of a scanning electron microscope and transmission electron microscope, the ultrathin fiber was demonstrated to have a fine linear morphology, smooth surface and obvious core-sheath structure. X-ray diffraction and Fourier transform infrared analyses showed that RE and AgNPs coexisted in the ultrathin fibers and had good compatibility with the polymeric matrices. The water contact angle experiments were conducted to evaluate the hydrophilicity and hygroscopicity of the fibers. In vitro dissolution tests revealed that RE was released in a sustained manner. In the antibacterial experiments against Staphylococcus aureus and Escherichia coli, the diameters of the inhibition zone of the fiber were 8.89 ± 0.09 mm and 7.26 ± 0.10 mm, respectively. Finally, cherry tomatoes were selected as the packaging object and packed with fiber films. In a practical application, the fiber films effectively reduced the bacteria and decreased the quality loss of cherry tomatoes, thereby prolonging the fresh-keeping period of cherry tomatoes to 12 days. Following the protocols reported here, many new food packaging films can be similarly developed in the future.


Asunto(s)
Nanopartículas del Metal , Zeína , Antibacterianos/química , Antibacterianos/farmacología , Escherichia coli , Embalaje de Alimentos/métodos , Nanopartículas del Metal/química , Polietilenglicoles , Plata/química , Plata/farmacología , Zeína/química
18.
Front Med (Lausanne) ; 9: 953103, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35991659

RESUMEN

Background: Immunosuppression is a risk factor for poor prognosis of critically ill patients, but current monitoring of the immune status in clinical practice is still inadequate. Absolute lymphocyte count (ALC) is not only a convenient biomarker for immune status monitoring but is also suitable for clinical application. In this study, we aimed to explore different trajectories of ALC, and evaluate their relationship with prognosis in critically ill patients. Methods: We retrospectively enrolled 10,619 critically ill patients admitted to a general intensive care unit (ICU) with 56 beds from February 2016 to May 2020. Dynamic ALC was defined as continuous ALC from before ICU admission to 5 days after ICU admission. Initial ALC was defined as the minimum ALC within 48 h after ICU admission. Group-based trajectory modeling (GBTM) was used to group critically ill patients according to dynamic ALC. Multivariate cox regression model was used to determine the independent association of trajectory endotypes with death and persistent inflammation, immunosuppression, catabolism syndrome (PICS). Results: A total of 2022 critically ill patients were unsupervisedly divided into four endotypes based on dynamic ALC, including persistent lymphopenia endotype (n = 1,211; 58.5%), slowly rising endotype (n = 443; 22.6%), rapidly decreasing endotype (n = 281; 14.5%) and normal fluctuation endotype (n = 87; 4.4%). Among the four trajectory endotypes, the persistent lymphopenia endotype had the highest incidence of PICS (24.9%), hospital mortality (14.5%) and 28-day mortality (10.8%). In multivariate cox regression model, persistent lymphopenia was associated with increased risk of 28-day mortality (HR: 1.54; 95% CI: 1.06-2.23), hospital mortality (HR: 1.66; 95% CI: 1.20-2.29) and PICS (HR: 1.79; 95% CI: 1.09-2.94), respectively. Sensitivity analysis further confirmed that the ALC trajectory model of non-infected patients and non-elderly patients can accurately distinguished 91 and 90% of critically ill patients into the same endotypes as the original model, respectively. Conclusion: The ALC trajectory model is helpful for grouping critically ill patients, and early persistent lymphopenia is associated with poor prognosis. Notably, persistent lymphopenia may be a robust signal of immunosuppression in critically ill patients.

19.
J Control Release ; 349: 963-982, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35944751

RESUMEN

Stimuli-responsive drug delivery systems based on polymeric nanovehicles are among the most promising treatment regimens for malignant cancers. Such intelligent systems that release payloads in response to the physiological characteristics of tumor sites have several advantages over conventional drug carriers, offering, in particular, enhanced therapeutic effects and decreased toxicity. The tumor microenvironment (TME) is acidic, suggesting the potential of pH-responsive nanovehicles for enhancing treatment specificity and efficacy. The synthetic polypeptide poly(l-histidine) (PLH) is an appropriate candidate for the preparation of pH-responsive nanovehicles because the pKa of PLH (approximately 6.0) is close to the pH of the acidic TME. In addition, the pendent imidazole rings of PLH yield pH-dependent hydrophobic-to-hydrophilic phase transitions in the acidic TME, triggering the destabilization of nanovehicles and the subsequent release of encapsulated chemotherapeutic agents. Herein, we highlight the state-of-the-art design and construction of pH-responsive nanovehicles based on PLH and discuss the future challenges and perspectives of this fascinating biomaterial for targeted cancer treatment and "benchtop-to-clinic" translation.


Asunto(s)
Doxorrubicina , Portadores de Fármacos , Materiales Biocompatibles , Histidina , Concentración de Iones de Hidrógeno , Imidazoles , Péptidos
20.
Biomater Sci ; 10(19): 5369-5390, 2022 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-35861101

RESUMEN

Porous organic polymers have received considerable attention in recent years because of their applicability as biomaterials. In particular, their hierarchical pore structures, variable morphologies, and tunable biological properties make them suitable as drug-delivery systems. In this review, the synthetic and post forming/control methods including templated methods, template-free methods, mechanical methods, electrospun methods, and 3D printing methods for controlling the hierarchical structures and morphologies of porous organic polymers are discussed, and the different methods affecting their specific surface areas, hierarchical structures, and unique morphologies are highlighted in detail. In addition, we discuss their applications in drug encapsulation and the development of stimuli (pH, heat, light, and dual-stimuli)-responsive materials, focusing on their use for targeted drug release and as therapeutic agents. Finally, we present an outlook concerning the research directions and applications of porous polymer-based drug delivery systems.


Asunto(s)
Sistemas de Liberación de Medicamentos , Polímeros , Materiales Biocompatibles/química , Sistemas de Liberación de Medicamentos/métodos , Liberación de Fármacos , Polímeros/química , Porosidad
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