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1.
Int J Biol Macromol ; : 132811, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38825282

RESUMO

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

2.
BMC Gastroenterol ; 23(1): 78, 2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36932326

RESUMO

BACKGROUND: To develop a new modality of colorectal cancer screening based on chronic disease management (CDM) to improve the participation rate of screening, and maximize the benefits of limited resources. METHODS: Patients under CDM were assigned to screening intervention group (SI) and screening control group1 (SC1), residents from natural community were assigned to screening control group2 (SC2). A parallel controlled community intervention study was performed. Only SI would achieve "one-to-one" intervention services. Meanwhile, 200 subjects were selected from each of the three groups for the Knowledge-Attitude-Practice (KAP) questionnaire before and after intervention, named questionnaire intervention group(QI), questionnaire control group1(QC1) and questionnaire control group2(QC2). The outcome of the intervention was evaluated using the difference-in-differences method and multiple regression analysis. RESULTS: The preliminary screening participation rate was 43.63%(473/1084) in SI, 14.32%(132/922) in SCI, and 5.87%(105/1789) in SC2. The baseline questionnaire showed low knowledge scores in the three questionnaire groups with no statistically significant differences, while attitude scores in QI and QC1 were significantly higher than QC2. The differences between baseline and terminal showed QI increased larger in knowledge and attitude scores than QC1 and QC2, while no difference was detected between QC1 and QC2. CONCLUSION: The colorectal cancer screening model based on chronic disease management effectively improved the screening participation rate, and the "one-to-one" intervention and the inherent characteristics of the patient population under CDM were the core elements of the new modality.


Assuntos
Neoplasias Colorretais , Detecção Precoce de Câncer , Humanos , Detecção Precoce de Câncer/métodos , Neoplasias Colorretais/epidemiologia , Conhecimentos, Atitudes e Prática em Saúde , Análise Multivariada , Gerenciamento Clínico , Programas de Rastreamento
3.
ACS Appl Mater Interfaces ; 14(48): 54225-54232, 2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36441914

RESUMO

Nylon-cotton (NC) blend fabrics are widely used in military and industrial applications, but their high flammability still remains a serious problem. In an effort to effectively and quickly impart flame retardancy to the NC fabric, it was treated by simply blade coating with a Cu2+-doped polyelectrolyte complex (CPEC) that consists of ammonium polyphosphate (APP), polyethylenimine (PEI), and copper sulfate. The viscosity of the CPEC can be adjusted by altering the content of CuSO4, which controls the amount of extrinsic and intrinsic ion pairs. By adjusting the proportion and content of PEI, APP, and CuSO4, CPEC suitable for treating the NC fabric was obtained. Only 0.067 wt % Cu2+ was needed to adjust the viscosity and impart self-extinguishing behavior in a vertical burning test. This simple two-step treatment provides a promising technology to protect flammable polymeric substrates with ultralow metal-doped polyelectrolyte complexes.

4.
Zhongguo Zhong Yao Za Zhi ; 46(17): 4360-4366, 2021 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-34581038

RESUMO

Diosgenin is widely distributed in many plants, such as Polygonatum sibiricum, Paris polyphylla, Dioscorea oppositifolia, Trigonella foenum-graecum, Costus speciosus, Tacca chantrieri, which has good anti-tumor activity and preferable effects on preventing atherosclerosis, protecting the heart, treating diabetes, etc. This review combed through the anti-tumor mechanisms of diosgenin encompassing lung, breast, gallbladder, liver, oral cavity, stomach, bladder, bone marrow, etc. Besides, it was discovered that diosgenin mainly exerts its effect by inhibiting tumor cell migration, suppressing tumor cell proliferation and growth, and inducing cell apoptosis. However, problems like low yield and bioavailability frequently exist in natural diosgenin. This review introduced methods such as structural modification, dosage form optimization and combination medication to improve the yield and anti-tumor activity of diosgenin. Via the summary of this paper, it is expected to provide theoretical basis for the rational exploitation and utilization of diosgenin.


Assuntos
Produtos Biológicos , Diosgenina , Trigonella , Apoptose , Proliferação de Células , Diosgenina/farmacologia
5.
Medicine (Baltimore) ; 98(18): e15140, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31045757

RESUMO

RATIONALE: Idiopathic pulmonary fibrosis (IPF) is a special form of spontaneous, chronic, progressive interstitial fibrotic pneumonia of unknown cause, and treatments for IPF have shown a poor prognosis. This study reports a new treatment, traditional Chinese medicine (TCM) therapy, for tonifying Qi-deficiency of lung-kidney in a 64-year-old patient with IPF. PATIENT CONCERNS: A 64-year-old man, who complained of cough and asthma, was diagnosed as IPF with mild impairment in lung function by thoracic high-resolution computed tomography and pulmonary function test. He received an 18-month N-acetylcysteine monotherapy but had no improvement in lung function. DIAGNOSES: IPF with mild impairment in lung function was diagnosed. INTERVENTIONS: The Chinese herbal medicine composition was decocted in 300 ml water for oral administration with 150 ml decoction twice daily in June 2017. OUTCOMES: The pulmonary function test showed that diffusing capacity for carbon monoxide had increased to 81% of predicted back to normal after 2-month TCM monotherapy. And diffusing capacity for carbon monoxide had increased to 89% of predicted, and forced expiratory volume in 1 s/forced vital capacity ratio increased to 92% at 14-month follow-up. No adverse events occurred during the 14 months of therapy and observation. LESSONS: The treatment by TCM therapy of tonifying lung-kidney's Qi-deficiency for IPF can improve the pulmonary function and reverse disease progression; it may be considered as a complementary treatment for IPF with mild-to-moderate impairment. However, the insights provided in this case report require further exploration and verification.


Assuntos
Fibrose Pulmonar Idiopática/terapia , Rim/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Medicina Tradicional Chinesa/métodos , Acetilcisteína/uso terapêutico , Monóxido de Carbono/metabolismo , Progressão da Doença , Expectorantes/uso terapêutico , Volume Expiratório Forçado/efeitos dos fármacos , Humanos , Fibrose Pulmonar Idiopática/diagnóstico por imagem , Fibrose Pulmonar Idiopática/mortalidade , Fibrose Pulmonar Idiopática/fisiopatologia , Rim/fisiopatologia , Pulmão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Capacidade de Difusão Pulmonar/efeitos dos fármacos , Testes de Função Respiratória/métodos , Resultado do Tratamento , Capacidade Vital/efeitos dos fármacos , Deficiência da Energia Yin
6.
Materials (Basel) ; 12(1)2019 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-30621247

RESUMO

Polypropylene (PP) is currently widely used in areas requiring lightweight materials because of its low density. Due to the intrinsic flammability, the application of PP is restricted in many conditions. Aluminum trihydroxide (ATH) is reported as a practical flame retardant for PP, but the addition of ATH often diminishes the lightweight advantage of PP. Therefore, in this work, glass bubbles (GB) and octacedylamine-modified zirconium phosphate (mZrP) are introduced into the PP/ATH composite in order to lower the material density and simultaneously maintain/enhance the flame retardancy. A series of PP composites have been prepared to explore the formulation which can endow the composite with balanced flame retardancy, good mechanical properties, and low density. The morphology, thermal stability, flame retardancy, and mechanical properties of the composites were characterized. The results indicated the addition of GB could reduce the density, but decreased the flame retardancy of PP composites at the same time. To overcome this defect, ATH and mZrP with synergetic effect of flame retardancy were added into the composite. The dosage of each additive was optimized for achieving a balance of flame retardancy, good mechanical properties, and density. With 47 wt % ATH, 10 wt % GB, and 3 wt % mZrP, the peak heat release rate (pHRR) and total smoke production (TSP) of the composite PP-4 were reduced by 91% and 78%, respectively. At the same time, increased impact strength was achieved compared with neat PP and the composite with ATH only. Maintaining the flame retardancy and mechanical properties, the density of composite PP-4 (1.27 g·cm-3) is lower than that with ATH only (PP-1, 1.46 g·cm-3). Through this research, we hope to provide an efficient approach to designing flame retardant polypropylene (PP) composites with low density.

7.
Carbohydr Polym ; 206: 609-615, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30553364

RESUMO

Self-cross-linked aerogel based on pectin and melamine-formaldehyde resin (MF) was fabricated via freeze-drying method using water as solvent, where pectin is structural material meanwhile acting as acid to catalyse the cross-linking of MF. The cross-linking reaction easily occurs without additional additives, which can be significantly accelerated at elevated temperatures, with a critical value of about 55 °C. The obtained aerogel shows network microstructures as observed with SEM. With increasing pectin content, the aerogel shows significantly increased compressive modulus. The compressive modulus of M10Pe5 arrives 23.2 MPa, the specific modulus of which arrives 188 MPa cm3/g, while pure MF aerogel are too fragile to keep intact after freeze-dried. The resulting aerogel has good thermal stability, excellent water resistance (can be second dried with limited strength loss) and low flammability. This partially bio-based novel aerogel with impressive properties is promising in many applications.

8.
ACS Appl Mater Interfaces ; 7(3): 1780-6, 2015 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-25588129

RESUMO

Ammonium polyphosphates (APP) modified with piperazine (PA-APP) was used to improve the flame retardancy of poly(vinyl alcohol) (PVA)/montmorillonite (MMT) aerogels, which were prepared via an environmentally friendly freeze-drying method. The thermal stabilities of the samples were evaluated by thermogravimetric analysis (TG); the flammability behaviors of samples were investigated by limiting oxygen index (LOI), vertical burning test (UL-94) and cone calorimeter (CC) tests. TG test results showed that the 5% weight loss temperature (T5%) of PVA/MMT/PA-APP was 10 °C higher than that of PVA/MMT/APP. In combustion testing, all of PVA/MMT/PA-APP aerogels achieved V-0 ratings and have a higher LOI values than the unmodified PVA/MMT aerogel. Moreover, the aerogel with 1% PA-APP5, which means that the content of piperazine is 5% in PA-APP, decreased the cone calorimetry THR value to 5.71 MJ/m(2), and increased the char residue to 52%. The compressive modulus of PVA/MMT/PA-APP was increased by 93.4% compared with PVA/MMT/APP because of the increase in interfacial adhesion between matrix and PA-APP fillers. The densities of the PVA/MMT/PA-APP samples were slightly lower than those of the unmodified aerogels because of reduced shrinkage in the presence of PA-APP. All the tests results indicated that the incorporation of PA-APP not only improved the thermal stability and flame retardancy of aerogels but also maintained their mechanical properties.

9.
Nat Prod Res ; 28(19): 1544-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24941113

RESUMO

Penifupyrone (1), a new funicone derivative, has been isolated from the endophytic fungus Penicillium sp. HSZ-43, along with three known analogues, funicone (2), deoxyfunicone (3) and 3-O-methylfunicone (4). These structures were identified by using spectroscopic methods, including UV, MS, 1D and 2D NMR experiments. The structure of 1 was confirmed by single-crystal X-ray diffraction analysis. All the isolated compounds were evaluated for cytotoxicity against human oral epidermoid carcinoma KB cells, and compound 1 exhibited moderate cytotoxic activity with IC50 value of 4.7 µM.


Assuntos
Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Penicillium/química , Antineoplásicos/química , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Concentração Inibidora 50 , Células KB , Conformação Molecular , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Pironas , Tripterygium/microbiologia
10.
ACS Appl Mater Interfaces ; 6(10): 7363-70, 2014 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-24742305

RESUMO

We found in our previous study that ethylenediamine- or ethanolamine-modified ammonium polyphosphates could be used alone as an intumescent flame retardant for polypropylene (PP), but their flame-retardant efficiency was not very high. In this present work, a novel highly-efficient mono-component polymeric intumescent flame retardant, piperazine-modified ammonium polyphosphate (PA-APP) was prepared. The oxygen index value of PP containing 22 wt % of PA-APP reached 31.2%, which increased by 58.4% compared with that of PP with equal amount of APP, and the vertical burning test (UL-94) could pass V-0 rating. Cone calorimeter (CC) results indicated that PP/PA-APP composite exhibited superior performance compared with PP/APP composite. For PP containing 25 wt % of PA-APP, fire growth rate (FGR) and smoke production rate (SPR) peak were reduced by 86.4% and 78.2%, respectively, compared with PP blended with 25 wt % APP. The relevant flame-retardant mechanism of PA-APP was investigated by Fourier transform infrared spectroscopy etc. The P-N-C structure with the alicyclic amine was formed during the thermal decomposition of piperazine salt (-NH2(+)-O-P-), and the rich P-N-C structure facilitated the formation of stable char layer at the later stage, consequently improving the flame-retardant efficiency of APP.

11.
Ying Yong Sheng Tai Xue Bao ; 22(11): 3039-46, 2011 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-22303685

RESUMO

Isaria farinosa is an important entomopathogenic fungus. By using ISSR, this paper studied the genetic heterogeneity of six I. farinosa populations at different localities of Anhui Province, East China. A total of 98.5% polymorphic loci were amplified with ten polymorphic primers, but the polymorphism at population level varied greatly, within the range of 59.6%-93.2%. The genetic differentiation index (G(st)) between the populations based on Nei's genetic heterogenesis analysis was 0.3365, and the gene flow (N(m)) was 0.4931. The genetic differentiation between the populations was lower than that within the populations, suggesting that the genetic variation of I. farinosa mainly come from the interior of the populations. The UPGMA clustering based on the genetic similarities between the isolates revealed that the Xishan population was monophylectic, while the other five populations were polyphylectic, with the Yaoluoping population being the most heterogenic and the Langyashan population being the least heterogenic. No correlations were observed between the geographic distance and the genetic distance of the populations. According to the UPGMA clustering based on the genetic distance between the populations, the six populations were classified into three groups, and this classification was accorded with the clustering based on geographic environment, suggesting the effects of environmental heterogeneity on the population heterogeneity.


Assuntos
Heterogeneidade Genética , Hypocreales/classificação , Hypocreales/genética , Repetições de Microssatélites , Animais , China , Furanos , Polimorfismo Genético , Dinâmica Populacional
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