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1.
J Community Psychol ; 51(2): 560-583, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-35195287

RESUMO

Low-income families in urbsan China have been benefited from the Minimum Living Standard Guarantee Assistance (dibao) policy since 1999. However, little is known about how child-specific family expenditure patterns impact child outcomes. Based on 2531 children aged 8-16 years from the National Survey of Social Policy Support System for Low-Income Families in Urban and Rural China, this is the first study of its kind to (1) identify family expenditure patterns (food, apparel, housing, transportation, pocket money, after-school education, and other educational resources) among low-income families and (2) examine their relationship with child suicide risks and developmental outcomes (academic performance, mental health, and physical health) by sex and across the dibao and marginalized families (i.e., without dibao). Latent profile analysis identified two patterns. Profile 1 (97.59%) showed low expenditure on children. Profile 2 (2.41%) prioritized expenditure in after-school programs. Mixed-effects logistic regression showed male children from marginalized families in Profile 1 are 11 times (95% confidence interval 1.10-109.52) more likely to think about suicide than female children from dibao families in Profile 2. Social policies and interventions promoting educational expenditure support and addressing the social determinants of health have the potential to reduce child suicide and improve child developmental outcomes among the urban poor.


Assuntos
Desenvolvimento Infantil , Ideação Suicida , Masculino , Humanos , Feminino , Gastos em Saúde , Pobreza , China
2.
Molecules ; 27(21)2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36364481

RESUMO

Due to their high sensitivity to temperature and humidity, the applications of polylactic acid (PLA) products are limited. The stereo-complexation (SC) formed by poly(L-lactic acid) (PLLA) and its enantiomer poly(D-lactic acid) (PDLA) can effectively improve the heat resistance and hydrolysis resistance of PLA products. In this work, the blended melt-spinning process of PLLA/PDLA was carried out using a polyester fiber production line to obtain PLA fiber with a complete SC structure. The effects of high-temperature tension heat-setting on the crystalline structure, thermal properties, mechanical properties, and hydrolysis resistance were discussed. The results indicated that when the tension heat-setting temperature reached 190 °C, the fiber achieved an almost complete SC structure, and its melting point was 222.5 °C. An accelerated hydrolysis experiment in a 95 °C water bath proved that the SC crystallites had better hydrolysis resistance than homocrystallization (HC). The monofilament strength retention rate of SC-190 fiber reached as high as 78.5% after hydrolysis for 24 h, which was significantly improved compared with PLLA/PDLA drawn fiber.


Assuntos
Poliésteres , Polímeros , Polímeros/química , Hidrólise , Poliésteres/química , Ácido Láctico/química
3.
Polymers (Basel) ; 13(12)2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34208303

RESUMO

The melt blending of polylactic acid (PLA) and thermoplastic silicone polyurethane (TPSiU) elastomer was performed to toughen PLA. The molecular structure, crystallization, thermal properties, compatibility, mechanical properties and rheological properties of the PLA/TPSiU blends of different mass ratios (100/0, 95/5, 90/10, 85/15 and 80/20) were investigated. The results showed that TPSiU was effectively blended into PLA, but no chemical reaction occurred. The addition of TPSiU had no obvious effect on the glass transition temperature and melting temperature of PLA, but slightly reduced the crystallinity of PLA. The morphology and dynamic mechanical analysis results demonstrated the poor thermodynamic compatibility between PLA and TPSiU. Rheological behavior studies showed that PLA/TPSiU melt was typically pseudoplastic fluid. As the content of TPSiU increased, the apparent viscosity of PLA/TPSiU blends showed a trend of rising first and then falling. The addition of TPSiU had a significant effect on the mechanical properties of PLA/TPSiU blends. When the content of TPSiU was 15 wt%, the elongation at break of the PLA/TPSiU blend reached 22.3% (5.0 times that of pure PLA), and the impact strength reached 19.3 kJ/m2 (4.9 times that of pure PLA), suggesting the favorable toughening effect.

4.
Front Pharmacol ; 11: 569800, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33551795

RESUMO

Juglans mandshurica Maxim., also known as "Manchurian walnut" (Chinese) and "Onigurumi" (Japanese), is a medicinal plant widely distributed in Western and Central Asia, especially in China. It has been traditionally used to treat cancer, gastric ulcers, diarrhea, dysentery, dermatosis, uterine prolapse, and leukopenia. To date, more than 400 constituents including quinones (e.g. naphthoquinones, anthraquinones, naphthalenones, tetralones), phenolics, flavonoids, triterpenoids, coumarins, lignans, phenylpropanoids, diarylheptanoids, and steroids, were isolated and structurally identified from different plant parts of J. mandshurica. Among them, quinones, phenolics, triterpenoids, and diarylheptanoids, as the major bioactive substances, have been extensively studied and displayed significant bioactivity. Previous studies have demonstrated that J. mandshurica and a few of its active components exhibit a wide range of pharmacologically important properties, such as antitumor, immunomodulatory, anti-inflammatory, neuroprotective, anti-diabetic, antiviral, antimicrobial, and anti-melanogenesis activities. However, many investigations on biological activities were mainly based on crude extracts of this plant, and the major bioactive ingredients responsible for these bioactivities have not been well identified. Further in vitro and in vivo studies on the mechanisms of action of the pure bioactive compounds, and more elaborate toxicity studies as well as clinical studies are needed to ensure safety and effectiveness of the plant for human use. Taken together, the present review will provide some specific useful suggestions guide to further investigations and applications of this plant in the preparation of medicines and functional foods.

5.
Am J Chin Med ; 47(5): 959-1003, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31416340

RESUMO

The present review is aimed at providing a comprehensive summary of the botanical characteristics, ethnomedicinal uses, phytochemical, pharmacological, and toxicological studies of the genus Ajuga L. The extensive literature survey revealed Ajuga L. species to be a group of important medicinal plants used for the ethnomedical treatment of rheumatism, fever, gout, sclerosis, analgesia, inflammation, hypertension, hyperglycemia, joint pain, palsy, amenorrhea, etc., although only a few reports address the clinical use and toxicity of these plants. Currently, more than 280 chemical constituents have been isolated and characterized from these plants. Among these constituents, neo-clerodane diterpenes and diterpenoids, phytoecdysteroids, flavonoids, and iridoids are the major bioactive compounds, possessing wide-reaching biological activities both in vivo and in vitro, including anti-inflammatory, antinociceptive, antitumor, anti-oxidant, antidiabetic, antimicrobial, antifeedant, antidiarrhoeal, hypolipidemic, diuretic, hypoglycaemic, immunomodulatory, vasorelaxant, larvicidal, antimutagenic, and neuroprotective activity. This review is aimed at summarizing the current knowledge of the ethnomedicinal uses, phytochemistry, biological activities, and toxicities of the genus Ajuga L. to reveal its therapeutic potentials, offering opportunities for future researches. Therefore, more focus should be paid to gathering information about their toxicology data, quality-control measures, and the clinical application of the bioactive ingredients from Ajuga L. species.


Assuntos
Ajuga/química , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Compostos Fitoquímicos/farmacologia , Animais , Antidiarreicos/efeitos adversos , Antidiarreicos/química , Antidiarreicos/farmacologia , Antineoplásicos/efeitos adversos , Antineoplásicos/química , Antineoplásicos/farmacologia , Antioxidantes/efeitos adversos , Antioxidantes/química , Antioxidantes/farmacologia , Medicamentos de Ervas Chinesas/efeitos adversos , Humanos , Medicina Tradicional , Compostos Fitoquímicos/efeitos adversos , Compostos Fitoquímicos/química
6.
Polymers (Basel) ; 11(6)2019 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-31174406

RESUMO

Polylactic acid (PLA) is one of the most promising bio-based materials, but its inherent hydrophobicity limits its application. Although nanocellulose (NCC) is a desirable reinforcement for PLA, the poor interface compatibility between the two has been a challenge. In this work, hydroxyapatite (HAP) modified NCC was prepared, and the obtained NCC/HAP reinforcement was used to prepare PLA/NCC-HAP composites. Different ratios of NCC to HAP were studied to explore their effects on the mechanical and thermodynamic properties of the composites. When the ratio of NCC to HAP was 30/70, the tensile strength and tensile modulus of the composite film reached 45.6 MPa and 2.34 GPa, respectively. Thermogravimetric analysis results indicate that thermal stability of the composites was significantly improved compared with pure PLA, reaching 346.6 °C. The above revelations show that NCC/HAP significantly improved the interface compatibility with PLA matrix.

7.
Mol Immunol ; 108: 81-88, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30784766

RESUMO

High altitude cerebral edema (HACE), whose development process is associated with oxidative stress and inflammatory response, is a life-threatening condition caused by rapid ascent speed to high altitudes. Phenylethanoid glycosides (PhGCs) are primary active constituents isolated from Phlomis younghusbandii Mukerjee that reportedly exhibit potent anti-oxidant and anti-inflammatory activities. The present study aims to investigate the protective effect of phenylethanoid glycosides (PhGCs) from P. younghusbandii in acute hypobaric hypoxia (AHH) - stimulated HACE rats and its underlying mechanisms. The expression of pro-inflammatory cytokine levels (IL-1ß, TNF-α, and IL-6) was detected by RT-PCR and ELISA at mRNA and protein levels in brain tissues. Western blotting was carried out to measure the major protein levels (IL-1ß, TNF-α, and NF-κB) in brain tissues. The oxidative stress biomarkers (MDA, SOD, and GSH) were evaluated using kits. Results demonstrate that PhGCs significantly improved pathological changes in brain tissues, reduced the brain's water content, and attenuated the production and mRNA expression of pro-inflammatory cytokines. Furthermore, the increased oxidative stress and the decrease in anti-oxidant stress system under the AHH condition were also abrogated reversely through PhGCs treatment by elevating the levels of SOD and GSH and suppressing the accumulation of MDA. Simultaneously, there was also a significant reduction in NF-κB, IL-1ß, and TNF-α protein expression levels in brain tissues, suggesting that blocking the NF-κB signaling pathway activation prevented the production of pro-inflammatory cytokines. Taken together, these findings indicate that PhGCs may afford a protectively intervene in HACE through the suppression of oxidative stress and inflammatory response via the inhibition of the NF-κB signaling pathway, indicating that PhGCs are promising agents for the treatment of acute HACE.


Assuntos
Doença da Altitude/tratamento farmacológico , Edema Encefálico/tratamento farmacológico , Edema Encefálico/etiologia , Glicosídeos/uso terapêutico , Hipóxia/complicações , Álcool Feniletílico/uso terapêutico , Phlomis/química , Doença Aguda , Animais , Citocinas/genética , Citocinas/metabolismo , Glicosídeos/farmacologia , Mediadores da Inflamação/metabolismo , Masculino , NF-kappa B/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Álcool Feniletílico/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , Água
8.
Materials (Basel) ; 11(5)2018 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-29772669

RESUMO

Hypereutectic Al⁻Si (20 wt.%) alloy parts were fabricated by employing a powder injection moulding (PIM) technique with a developed multi-component binder system composed of high-density polyethylene (35 wt.%), carnauba wax (62 wt.%) and stearic acid (3 wt.%). The feedstocks contained 83 wt.% metal powders. The debinding process was carried out by a combination of solvent extraction and thermal decomposition. The effects of solvent debinding variables such as kind of solvents, debinding temperatures and time, and the bulk surface area to volume ratios on the debinding process were investigated. Thermal debinding and the subsequent sintering process were carried out in a heating sequence under a nitrogen atmosphere. The influences of sintering temperature and sintering time on the mechanical properties and structure were considered. Under the optimal sintering condition, sintering at 550 °C for 3 h, the final sintering parts were free of distortion and exhibited good mechanical properties. Relative sintered density, Brinell hardness, and tensile strength were ~95.5%, 58 HBW and ~154, respectively.

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