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1.
Cell Mol Life Sci ; 80(10): 305, 2023 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-37752383

RESUMEN

Self-renewing, damage-repair and differentiation of mammalian stratified squamous epithelia are subject to tissue homeostasis, but the regulation mechanisms remain elusive. Here, we investigate the esophageal squamous epithelial tissue homeostasis in vitro and in vivo. We establish a rat esophageal organoid (rEO) in vitro system and show that the landscapes of rEO formation, development and maturation trajectories can mimic those of rat esophageal epithelia in vivo. Single-cell RNA sequencing (scRNA-seq), snapshot immunostaining and functional analyses of stratified "matured" rEOs define that the epithelial pluripotent stem cell determinants, p63 and Sox2, play crucial but distinctive roles for regulating mammalian esophageal tissue homeostasis. We identify two cell populations, p63+Sox2+ and p63-Sox2+, of which the p63+Sox2+ population presented at the basal layer is the cells of origin required for esophageal epithelial stemness maintenance and proliferation, whereas the p63-Sox2+ population presented at the suprabasal layers is the cells of origin having a dual role for esophageal epithelial differentiation (differentiation-prone fate) and rapid tissue damage-repair responses (proliferation-prone fate). Given the fact that p63 and Sox2 are developmental lineage oncogenes and commonly overexpressed in ESCC tissues, p63-Sox2+ population could not be detected in organoids formed by esophageal squamous cell carcinoma (ESCC) cell lines. Taken together, these findings reveal that the tissue homeostasis is maintained distinctively by p63 and/or Sox2-dependent cell lineage populations required for the tissue renewing, damage-repair and protection of carcinogenesis in mammalian esophagi.


Asunto(s)
Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Ratas , Animales , Neoplasias Esofágicas/genética , Mamíferos , Homeostasis , Carcinogénesis
2.
Macromol Rapid Commun ; 44(10): e2200977, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37002780

RESUMEN

The development of high-performance and low-cost, flexible electronic devices is a crucial prerequisite for emerging applications of energy storage, conversion, and sensing system. Collagen as the most abundant structural protein in mammals, owing to the unique amino acid composition and hierarchical structure, the conversion of collagen into collagen-derived carbon materials with different nanostructures and abundant ideal heteroatom doping through the carbonization method is expected to be a promising candidate material for electrodes of energy storage devices. The excellent mechanical flexibility of collagen and the abundant functional groups on its molecular chain that are easy to modify provide the possibility to be used as a separator material. On this basis, the ideal biocompatibility and degradability provide unique conditions for it to match the flexible substrate material of the human body for wearable electronic skin. In this review, the unique characteristics and advantages of collagen for electronic devices are first summarized. Recent progress in designing and constructing collagen-based electronic devices for future applications of electrochemical energy storage and sensing are reviewed. Finally, the challenges and prospects for collagen-based flexible electronic devices are discussed.


Asunto(s)
Nanoestructuras , Dispositivos Electrónicos Vestibles , Animales , Humanos , Electrónica , Carbono/química , Nanoestructuras/química , Colágeno , Mamíferos
3.
Biomacromolecules ; 23(6): 2264-2271, 2022 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-35324155

RESUMEN

With the emergence of efficient green solvents, structural regulation of regenerated cellulose is highly desired in the solution process from an industrial perspective. Cellulose fiber and films are viewed as a "composite" comprising amorphous and crystalline fractions. The regulation of the crystalline structure is of great importance for the properties of cellulose materials. In this study, we found stretch-induced crystallization behavior during the transition from solution to gel via coagulation. The crystallinity index of the hydrogel fiber increases with the stretch ratio (SR). X-ray diffraction revealed that the cellulose II hydrate formed in the stretched hydrogel fibers. The mechanical properties and thermal stability of the dry fibers greatly improved against the SR. This crystallization behavior depends on the concentration of the solution and the type of ionic liquid. This stretch-induced crystallization provides an efficient method for structural regulation in cellulose solution processing.


Asunto(s)
Líquidos Iónicos , Celulosa/química , Cristalización , Hidrogeles , Líquidos Iónicos/química , Difracción de Rayos X
4.
Am Surg ; 90(4): 600-606, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37751620

RESUMEN

OBJECTIVE: The objective of this study is to investigate the epidemiological features, clinical characteristics, and pathological characteristics of acral lentiginous melanoma (ALM) and identify prognostic factors. METHODS: A total of 149 patients diagnosed with ALM between August 2008 and December 2019 at the National Cancer Center (NCC) of China were retrospectively analyzed. Follow-up data on patient survival status were collected. Survival curves were generated using the Kaplan-Meier method, and statistical significance was assessed using the log-rank test. Additionally, a Cox proportional hazards model was constructed to identify prognostic factors. RESULTS: All patients included in this study were of Chinese ethnicity, with an average age of 52.4 ± 14.8 years (range, 15-80 years) at the time of diagnosis. No gender predilection or genetic susceptibility was observed. The plantar region was the most frequently affected site among primary lesions. Notably, only 17 (11.4%) patients reported a history of trauma. Statistical analysis revealed that a lesion duration of ≤2.5 years, Breslow thickness >4.0 mm, high mitotic rate (>6 mm-2), presence of vascular invasion, and regional lymph node metastasis were identified as independent prognostic factors. CONCLUSION: Our findings indicate that a lesion duration of ≤2.5 years, Breslow thickness >4.0 mm, high mitotic rate (>6 mm-2), presence of vascular invasion, and regional lymph node metastasis are significantly associated with a poorer prognosis for patients with ALM.


Asunto(s)
Melanoma , Neoplasias Cutáneas , Adulto , Anciano , Humanos , Persona de Mediana Edad , Metástasis Linfática , Melanoma/diagnóstico , Estudios Retrospectivos , Adolescente , Adulto Joven , Anciano de 80 o más Años , Pueblos del Este de Asia
5.
Heliyon ; 10(9): e30457, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38720734

RESUMEN

Organoids are three-dimensional structures derived from primary tissue or tumors that closely mimic the architecture, histology, and function of the parental tissue. In recent years, patient-derived organoids (PDOs) have emerged as powerful tools for modeling tumor heterogeneity, drug screening, and personalized medicine. Although most cancer organoids are derived from primary tumors, the ability of organoids from metastatic cancer to serve as a model for studying tumor biology and predicting the therapeutic response is an area of active investigation. Recent studies have shown that organoids derived from metastatic sites can provide valuable insights into tumor biology and may be used to validate predictive models of the drug response. In this comprehensive review, we discuss the feasibility of culturing organoids from multiple metastatic cancers and evaluate their potential for advancing basic cancer research, drug development, and personalized therapy. We also explore the limitations and challenges associated with using metastasis organoids for cancer research. Overall, this review provides a comprehensive overview of the current state and future prospects of metastatic cancer-derived organoids.

6.
Food Chem ; 438: 138009, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-37983991

RESUMEN

In this work, a nontoxic crosslinking agent, citric acid (CA), was used to crosslink glycerol-plasticized SSPS films via a heat activated reaction. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy results confirmed the occurrence of esterification reaction between CA and SSPS. Microstructure of the CA-crosslinked SSPS films were characterized by scanning electron microscopy, atomic force microscopy and X-ray diffraction. The water resistance, mechanical, UV-barrier, water vapor barrier, antioxidant and thermal properties of SSPS films were enhanced by CA crosslinking. The SSPS film crosslinked with 5 % CA exhibited a maximum tensile strength of 6.5 MPa and a minimum water solubility of 34.3 %. The CA-crosslinked SSPS film also presented superior antibacterial properties against Gram-positive and Gram-negative bacteria. Application test results showed that the CA-crosslinked SSPS film can effectively delay the oxidative deterioration of lard during storage, suggesting that the developed CA-crosslinked SSPS film could be a promising candidate for active food packaging.


Asunto(s)
Antibacterianos , Glycine max , Antibacterianos/farmacología , Antibacterianos/química , Embalaje de Alimentos/métodos , Bacterias Gramnegativas , Bacterias Grampositivas , Polisacáridos/química , Permeabilidad
7.
J Hematol Oncol ; 17(1): 71, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39164791

RESUMEN

Osteosarcomas are intricate cellular ecosystems, where heterotypic interactions significantly influence disease progression and therapeutic outcomes. Despite their importance, a detailed understanding of their cellular composition and organizational structure remains elusive. In this study, we provide a comprehensive single-cell and spatially resolved transcriptomics analysis of human osteosarcomas. We construct a cellular meta-map to dissect spatial transcriptomic data, unveiling a detailed atlas of osteosarcoma compositional subgroups. We meticulously characterize the unique gene signatures and functional states of each subgroup and investigate the impact of chemotherapy on these cellular subpopulations. Additionally, our spatial transcriptomics analysis identifies a distinct spatial niche, located at the forefront of tumor necrotic zones, potentially associated with chemotherapy resistance. We also delve into the crosstalk between different cellular subgroups. This study furnishes a comprehensive transcriptional atlas of osteosarcoma's cellular architecture, enriching our comprehension of its complexity and laying the groundwork for more targeted therapeutic approaches.


Asunto(s)
Neoplasias Óseas , Osteosarcoma , Análisis de la Célula Individual , Humanos , Osteosarcoma/patología , Osteosarcoma/genética , Neoplasias Óseas/patología , Neoplasias Óseas/genética , Transcriptoma , Perfilación de la Expresión Génica , Microambiente Tumoral , Regulación Neoplásica de la Expresión Génica
8.
J Cancer Res Clin Oncol ; 150(7): 356, 2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-39033089

RESUMEN

PURPOSE: Neoadjuvant chemotherapy serves as an effective strategy for treating osteosarcoma (OS) not only by targeting cancerous cells but also by influencing the tumor's immune and stromal elements. Gaining insights into how chemotherapy reshapes the tumor's local environment is crucial for advancing OS treatment protocols. METHODS: Using single-cell RNA sequencing, this study analyzed tumor samples from patients with advanced osteosarcoma collected both before and after chemotherapy. RESULTS: The results revealed that chemotherapy caused the remaining OS cells to express higher levels of genes associated with stemness. Additionally, this process enhances the presence of cancer-associated fibroblasts, increasing their ability to modify the extracellular matrix (ECM). Chemotherapy also increases the number of endothelial cells, albeit with compromised differentiation capabilities. Importantly, the treatment reduced the immune cell population, including myeloid and T/NK cells, particularly impacting the subpopulations with tumor-fighting capabilities. CONCLUSION: These findings highlight the complex reaction of the tumor environment to chemotherapy, providing valuable insights into how chemotherapy influences OS cells and the tumor microenvironment (TME). This knowledge is essential for understanding OS resistance mechanisms to treatments, potentially guiding the development of novel therapies for managing advanced OS.


Asunto(s)
Neoplasias Óseas , Osteosarcoma , Análisis de la Célula Individual , Transcriptoma , Microambiente Tumoral , Osteosarcoma/tratamiento farmacológico , Osteosarcoma/patología , Osteosarcoma/genética , Microambiente Tumoral/efectos de los fármacos , Humanos , Neoplasias Óseas/tratamiento farmacológico , Neoplasias Óseas/patología , Neoplasias Óseas/genética , Análisis de la Célula Individual/métodos , Terapia Neoadyuvante , Fibroblastos Asociados al Cáncer/patología , Fibroblastos Asociados al Cáncer/metabolismo , Fibroblastos Asociados al Cáncer/efectos de los fármacos , Femenino , Masculino , Adulto
9.
Int J Biol Macromol ; 261(Pt 1): 129739, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38281529

RESUMEN

A hybrid hydrogel system (GSOHA) consisting of serotonin-grafted gelatin and oxidized hyaluronic acid (OHA) was developed in this study to efficiently control bleeding and prevent bacterial infections during surgery and trauma. The study results showed that the incorporation of serotonin successfully produced hydrogels with rapid hemostatic, antibacterial, and antioxidant properties. The GSOHA hydrogel exhibited considerably stronger tissue adhesion (15.55 ± 0.36 kPa) to porcine skin than the commercial fibrin glue (1.09 ± 0.04 kPa). In addition, the hydrogel could rapidly absorb blood cells and stimulate cell conjugation with serotonin addition. In vitro experiments using endothelial cells and erythrocytes demonstrated the excellent biocompatibility and hemocompatibility of the hydrogel. Most importantly, the GSOHA hydrogel accelerated the wound healing process in a full-thickness skin defect mice model, and the histological staining results demonstrated that GSOHA significantly promoted collagen deposition and vascularization. In conclusion, this study demonstrated the significant potential of the GSOHA hydrogel as an adhesive dressing for rapid hemostasis and wound healing.


Asunto(s)
Gelatina , Ácido Hialurónico , Animales , Ratones , Porcinos , Gelatina/farmacología , Ácido Hialurónico/farmacología , Hidrogeles/farmacología , Serotonina/farmacología , Células Endoteliales , Cicatrización de Heridas , Antibacterianos , Hemostasis
10.
Carbohydr Polym ; 330: 121776, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38368092

RESUMEN

The present work investigates the effects of nano-chitin with different charge, obtained by acid hydrolysis and TEMPO oxidation, on the structure and properties of borax crosslinked polyvinyl alcohol (PVA) hydrogels. In detail, nano-chitin prepared by acid hydrolysis (ACh) is positively charged (+28.8 mV). The electrostatic attraction between ACh and borax ions leads to a maximum tensile stress of composite hydrogel (ACh/PB), 54.25 KPa, 17 times of the borax crosslinked PVA (PB). In contrast, nano-chitin prepared by TEMPO-oxidation (TCh) shows negative charge (-59.0 mV). Due to the electrostatic repulsion with borax ions, the maximum tensile stress of composite hydrogel (TCh/PB) is only 9.25 KPa, a very limit reinforcing effect. However, TCh/PB showed better self-healing efficiency (96.0 %) as well as ionic conductivity (1.25 × 10-5 S/m). The present work shows that the charge state of the nano-chitin exerts great influence on the interaction with the crosslinking agent borax, therefore, affects the structure and properties of the final PVA composite hydrogels. The results could provide important information about making full use of nano-chitin as a reinforcement by adjusting its surface charge state.

11.
Int J Biol Macromol ; 277(Pt 2): 134222, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39074697

RESUMEN

In this work, carboxymethylated curdlan (CMCD) was utilized as a capping and stabilizing agent for the green synthesis of silver nanoparticles. Subsequently, quaternized curdlan (QCD) was introduced as the second capping layer through electrostatic attraction, leading to the preparation of double-capped silver nanoparticles (AgNPs@CQ). The successful synthesis of silver nanoparticles was characterized using UV-vis, FTIR, XRD, TEM, and DLS. AgNPs@CQ were incorporated into gelatin and a AgNPs@CQ/Gel composite hydrogel was obtained. The incorporation of AgNPs@CQ imparts excellent antibacterial properties to the composite hydrogel, thereby enhancing its antimicrobial efficacy. The presence of double-capping layers significantly retards the release rate of silver, contributing to prolonged antimicrobial activity. The MTT and live/dead fluorescence staining results demonstrate that the gelatin hydrogel incorporating double-capped AgNPs exhibits enhanced cell viability compared to the one incorporating single-capped AgNPs. Additionally, the composite hydrogel exhibits remarkable mechanical strength and adhesive performance. The AgNPs@CQ/Gel composite hydrogel demonstrates a cost-effective and facile preparation, showing significant potential in the field of dressings.


Asunto(s)
Antibacterianos , Gelatina , Hidrogeles , Nanopartículas del Metal , Plata , beta-Glucanos , Plata/química , beta-Glucanos/química , Gelatina/química , Nanopartículas del Metal/química , Antibacterianos/farmacología , Antibacterianos/química , Hidrogeles/química , Preparaciones de Acción Retardada , Pruebas de Sensibilidad Microbiana , Supervivencia Celular/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos
12.
Cancer Lett ; 588: 216813, 2024 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-38499266

RESUMEN

Rat model of N-nitrosomethylbenzylamine (NMBzA)-induced esophageal squamous cell carcinoma (ESCC) is routinely used to study ESCC initiation, progression and new therapeutic strategies. However, the model is time-consuming and malignant tumor incidences are low. Here, we report the usage of multi-kinase inhibitor sorafenib as a tumor promoter to establish an efficient two-stage NMBzA-induced rat ESCC carcinogenesis model, resulting in increments of tumor incidences and shortened tumor formation times. By establishing the model and applying whole-genome sequencing, we discover that benign papillomas and malignant ESCCs harbor most of the "driver" events found in rat ESCCs (e.g. recurrent mutations in Ras family, the Hippo and Notch pathways and histone modifier genes) and the mutational landscapes of rat and human ESCCs overlap extensively. We generate tumor cell lines derived from NMBzA-induced papillomas and ESCCs, showing that papilloma cells retain more characteristics of normal epithelial cells than carcinoma cells, especially their exhibitions of normal rat cell karyotypes and inabilities of forming tumors in immunodeficient mice. Three-dimensional (3-D) organoid cultures and single cell RNA sequencing (scRNA-seq) indicate that, when compared to control- and papilloma-organoids, ESCC-organoids display salient abnormalities at tissue and single-cell levels. Multi-omic analyses indicate that NMBzA-induced rat ESCCs are accompanied by progressive hyperactivations of the FAT-Hippo-YAP1 axis and siRNA or inhibitors of YAP1 block the growth of rat ESCCs. Taken together, these studies provide a framework of using an effective rat ESCC model to investigate multilevel functional genomics of ESCC carcinogenesis, which justify targeting YAP1 as a therapeutic strategy for ESCC.


Asunto(s)
Carcinoma de Células Escamosas , Dimetilnitrosamina/análogos & derivados , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Papiloma , Humanos , Ratas , Ratones , Animales , Carcinoma de Células Escamosas de Esófago/genética , Carcinoma de Células Escamosas de Esófago/metabolismo , Neoplasias Esofágicas/inducido químicamente , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Carcinoma de Células Escamosas/inducido químicamente , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Línea Celular Tumoral , Carcinogénesis
13.
Am Surg ; 90(6): 1456-1462, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38525950

RESUMEN

BACKGROUND: Bariatric surgery is an effective treatment for morbid obesity. However, a subset of individuals seeking bariatric surgery may exhibit a metabolically healthy obesity (MHO) phenotype, suggesting that they may not experience metabolic complications despite being overweight. OBJECTIVE: This study aimed to determine the prevalence and metabolic features of MHO in a population undergoing bariatric surgery. METHODS: A representative sample of 665 participants aged 14 or older who underwent bariatric surgery at our center from January 1, 2010 to January 1, 2020 was included in this cohort study. MHO was defined based on specific criteria, including blood pressure, waist-to-hip ratio, and absence of diabetes. RESULTS: Among the 665 participants, 80 individuals (12.0%) met the criteria for MHO. Female gender (P = .021) and younger age (P < .001) were associated with a higher likelihood of MHO. Smaller weight and BMI were observed in individuals with MHO. However, a considerable proportion of those with MHO exhibited other metabolic abnormalities, such as fatty liver (68.6%), hyperuricemia (55.3%), elevated lipid levels (58.7%), and abnormal lipoprotein levels (88%). CONCLUSION: Approximately 1 in 8 individuals referred for bariatric surgery displayed the phenotype of MHO. Despite being metabolically healthy based on certain criteria, a significant proportion of individuals with MHO still exhibited metabolic abnormalities, such as fatty liver, hyperuricemia, elevated lipid levels, and abnormal lipoprotein levels, highlighting the importance of thorough metabolic evaluation in this population.


Asunto(s)
Cirugía Bariátrica , Obesidad Metabólica Benigna , Obesidad Mórbida , Humanos , Femenino , Masculino , Adulto , Prevalencia , Factores de Riesgo , Persona de Mediana Edad , Obesidad Metabólica Benigna/epidemiología , Obesidad Mórbida/cirugía , Obesidad Mórbida/metabolismo , Estudios de Cohortes , Adulto Joven , Adolescente
14.
Int J Biol Macromol ; 239: 124361, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-37028629

RESUMEN

Soluble soybean polysaccharide (SSPS)-based composite films with the addition of nano zinc oxide (nZnO, 5 wt% based on SSPS) and tea tree essential oil (TTEO, 10 wt% based on SSPS) were developed by the casting method. The effect of the combination of nZnO and TTEO on the microstructure and physical, mechanical and functional properties of SSPS films was evaluated. The results showed that the SSPS/TTEO/nZnO film exhibited enhanced water vapor barrier properties, thermal stability, water resistance, surface wettability, and total color difference, and almost completely prevented ultraviolet light transmission. The addition of TTEO and nZnO had no significant effect on the tensile strength and elongation at break of the films, but decreased the percentage of light transmittance of the films at 600 nm from 85.5 % to 10.1 %. The DPPH radical scavenging activity of the films significantly increased from 46.8 % (SSPS) to 67.7 % (SSPS/TTEO/nZnO) due to the presence of TTEO. Scanning electron microscopy analysis indicated that nZnO and TTEO were evenly dispersed in the SSPS matrix. The synergistic effect of nZnO and TTEO endowed the SSPS film with excellent antibacterial activity against E. coli and S. aureus, suggesting that the SSPS/TTEO/nZnO film could be a promising material for active packaging applications.


Asunto(s)
Aceite de Árbol de Té , Óxido de Zinc , Aceite de Árbol de Té/farmacología , Glycine max/química , Árboles , Embalaje de Alimentos/métodos , Óxido de Zinc/farmacología , Óxido de Zinc/química , Escherichia coli , Staphylococcus aureus , Polisacáridos/farmacología , Polisacáridos/química ,
15.
Waste Manag ; 143: 105-115, 2022 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-35240446

RESUMEN

Management and safe disposal of chrome-tanned leather wastes generated in leather industry are of great importance due to their potential health risks and environmental hazards. Herein, an integrated strategy was proposed for disposing of chrome-tanned leather scrap (CTLS). This method involves the separation of chromium salts from CTLS with sulfuric acid for recycling purpose, followed by pyrolysis of the acid-treated CTLS in an inert atmosphere. SEM/EDX analysis was employed to characterize the changes in composition and morphology of CTLS after acid treatment. CO2 and H2O are main pyrolysis gases of CTLS, while the acid treatment increases the relative content of aliphatic hydrocarbons and NH3 in evolved gases. The pyrolysis characteristics and kinetics of the acid-treated CTLS were investigated by thermogravimetric analysis (TGA) at three different heating rates. After 3 and 6 days of acid treatment, the average activation energy of CTLS (450.9 kJ/mol) obtained from the Flynn-Wall-Ozawa method decreased to 369.6 and 351.0 kJ/mol, respectively. It is assumed that the CTLS consists of two pseudocomponents: low-crosslinked collagen (LCol) and highly-crosslinked collagen (HCol). Using the generalized master plots method, random nucleation and nuclei growth model (An model) was found to be the most probable kinetic model for the pyrolysis process of LCol and HCol. The kinetic exponent for pseudocomponent pyrolysis varied between 3.00 and 3.90, and the pre-exponential factor ranged from 5.83 × 1012 to 2.93 × 1013 min-1. The results of the present study provide an alternative route and useful information for recycling and disposing of chrome-containing leather wastes.


Asunto(s)
Pirólisis , Ácidos Sulfúricos , Gases , Cinética , Termogravimetría
16.
RSC Adv ; 12(12): 7506-7515, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-35424668

RESUMEN

Leather is widely used in daily necessities, such as shoes and bags. Traditional chrome tanning might produce leathers with excellent mechanical and thermal properties but gives rise to problems, such as environmental pollution. To find an ecological alternative for chrome-tanning agents, soluble soybean polysaccharide (SSPS) was oxidized by sodium periodate to yield dialdehyde soluble soybean polysaccharide (DPA). By the response surface methodology (RSM)-based optimization of the preparation process, DPA was obtained at the optimized condition at the mass ratio of 1 : 1.9, oxidation time of 0.53 h, and oxidation temperature of 20 °C, and the hydrothermal shrinkage temperature of the DPA-tanned leather reached 79 °C. The Fourier transform infrared (FT-IR) spectra and gel permeation chromatography (GPC) showed that the aldehyde group was successfully introduced, and the molecular weight was significantly reduced. The DPA-tanned leather has good collagen fiber dispersion and mechanical properties and thus is suggested to be a green tanning agent for leather making.

17.
Int J Biol Macromol ; 222(Pt B): 3155-3167, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36243153

RESUMEN

Herein, a strong and stable gelatin-based composite hydrogel was fabricated by incorporation of amino-functionalized microfibrillated cellulose (AMFC) into gelatin matrix along with genipin crosslinking. The hydrogel consists of chemical and physical crosslinks among gelatin chains and AMFC fibrils. The morphology, swelling behavior and compressive properties of the composite hydrogels were investigated. The results show that the mechanical properties and structural stability of the gelatin hydrogels were improved remarkably by the addition of AMFC due to the formation of a hybrid network structure. The composite hydrogel has a compressive strength up to 1.52 MPa at a strain of 80 %, which is 41.2 and 1.8 times higher than that of the conventional physical and genipin-crosslinked gelatin hydrogels, respectively. Moreover, the developed gelatin-based composite hydrogels reinforced with AMFC exhibit good enzymatic stability, high surface hydrophobicity, tunable swelling property and excellent biocompatibility, which are expected to have potential applications in biomedical and pharmaceutical fields.


Asunto(s)
Gelatina , Hidrogeles , Gelatina/química , Hidrogeles/química , Celulosa/química , Iridoides
18.
Asian J Surg ; 45(9): 1682-1687, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34642048

RESUMEN

BACKGROUND: Roux-en-Y gastric bypass (RYGB) is considered the gold standard procedure for bariatric surgery that leads to sustained weight loss and amelioration of obesity-related comorbidities. OBJECTIVES: To verify long-term efficacy and safety and to investigate the influence of early weight loss on post-RYGB long-term weight maintenance in obese Chinese with body mass index (BMI) < 35 kg/m2. METHODS: All patients were followed up for evaluating the variations in their BMI, percentage of excess weight loss (%EWL), and total body percentage weight loss (%TWL). Linear regression models were applied to evaluate the effects of early weight loss on successful weight maintenance. Optimal cutoff values were analyzed via plotting the receiver operative characteristic (ROC) curve. RESULTS: In the current study, 143 patients were recruited. Preoperative BMI and weight were recorded as 32.24 (29.39-33.12) kg/m2, and 88.90 ± 9.52 kg, respectively. At 1, 3, and 5 years, successful weight loss i.e., greater than 25% TWL was attained by 46.85%, 37.76%, and 37.06% of patients, respectively. The obtained data revealed that %TWL at 0.5 years was considerably associated with %TWL for up to 5 years (P-value <0.001). Based on the ROC curve, %TWL of 24.39% at 0.5 years best predicted effective weight loss at 5 years (sensitivity 71.70%, specificity 82.22%). CONCLUSION: RYGB is a safe and effective approach for weight loss and %TWL at 6 months might be used for predicting weight maintenance up to 5 years post-RYGB in obese Chinese with a BMI <35 kg/m2.


Asunto(s)
Derivación Gástrica , Laparoscopía , Obesidad Mórbida , Índice de Masa Corporal , China , Derivación Gástrica/métodos , Humanos , Obesidad/complicaciones , Obesidad/cirugía , Obesidad Mórbida/complicaciones , Obesidad Mórbida/cirugía , Estudios Retrospectivos , Resultado del Tratamiento , Pérdida de Peso
19.
Int J Biol Macromol ; 166: 567-577, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33144252

RESUMEN

In the present work, a facile and green synthesis approach for the production of monodispersed, small-sized (2.9 ± 0.7 nm) and stable silver nanoparticles (AgNPs) using soluble soybean polysaccharide (SSPS) was reported. SSPS was used as the reducing and stabilizing agent. The obtained SSPS-stabilized AgNPs (SA) were characterized by UV-vis absorption spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, energy dispersive X-ray spectroscopy and transmission electron microscopy. The antimicrobial activity of the SA colloidal dispersion (SACD) was evaluated based on the growth kinetics of bacteria E. coli and S. aureus. Afterwards, the colloidal dispersion was applied as a coating material to Kraft paper. The SACD-coated Kraft paper exhibited excellent antimicrobial activity against above bacteria strains and P. aeruginosa. The effects of SACD coating on surface wettability, barrier property and microstructure of the Kraft paper were also studied. The results suggested that the SSPS-stabilized AgNPs have great potential in antibacterial applications.


Asunto(s)
Antibacterianos/farmacología , Materiales Biocompatibles Revestidos/farmacología , Glycine max/química , Tecnología Química Verde , Nanopartículas del Metal/química , Polisacáridos/farmacología , Plata/química , Coloides/química , Escherichia coli/efectos de los fármacos , Escherichia coli/crecimiento & desarrollo , Nanopartículas del Metal/ultraestructura , Pruebas de Sensibilidad Microbiana , Papel , Tamaño de la Partícula , Pseudomonas aeruginosa/efectos de los fármacos , Solubilidad , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrollo , Agua/química , Humectabilidad , Difracción de Rayos X
20.
J Colloid Interface Sci ; 582(Pt B): 610-618, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-32911409

RESUMEN

Ethanol was used to induce coacervation in aqueous solutions of gelatin. Coacervation resulted from phase separation driven by ethanol as a poor solvent for gelatin, impacting aggregation of gelatin chains. Static coacervation was performed to investigate coacervate morphology, and gelatin concentration and ethanol temperature influenced the morphologies of the gelatin coacervates. High-concentration gelatin solutions (>4.8 wt%) treated with lower temperature ethanol (<25 °C) formed network morphologies, while low-concentration gelatin solution (<4.8 wt%) treated with ethanol near room temperature formed nanosphere assemblies. Dispersive nanospheres were obtained after treatment with higher temperature ethanol (~45 °C). Stirring the mixture of gelatin solution and ethanol resulted in dispersed nanospheres where the size was adjusted by changing the volume ratio of aqueous gelatin solution and ethanol (VGel:VEtOH) and the gelatin concentration. Turbidity and absorbance measurements were carried out to further investigate coacervation dynamics. The cocervation system reached dynamic equilibrium according to the VGel:VEtOH, suggesting phase separation and molecular arrangements were key. DLS results showed that reversible changes in coacervate radius could be attained by periodic heating and cooling cycles (25-60 °C). This work provides useful information for constructing gelatin-based materials using a facile coacervation method.

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