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1.
Dalton Trans ; 49(18): 5823-5831, 2020 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-32297888

RESUMO

Herein, a simple green co-precipitation route for Mn4+-activated fluorides has been realized via individually using the aqueous acidic salt NH4HF2 as a solvent. The systematic explorations of ionization, erosion, solvent concentration, solvency on reactants, and reaction with an extra weak acid disclosed that the near-saturated aqueous NH4HF2, ionizing into abundant HF2-, H+, and F- ions, exhibited large dissolving capacity and good stabilization on Mn4+ without obvious toxicity. The green synthesized example of Cs2GeF6:Mn4+ emitted a typical narrow band red light at 633 nm with normal optimal doping at ∼8 at%. Compared with its contrast prepared from the HF system, it experienced only ∼10% reduction in quantum efficiency and slight emission attenuation below 150 °C as the more humidity-sensitive weaker acid surface aroused lattice thermal vibration. The further action as red component fabricated a high-quality warm white light-emitting diode (W-LED) with a high color rendering index (Ra ∼ 91), high luminous efficacy (∼149 lm W-1), low correlated color temperature (∼3211 K), and good color stability against the operating environment. Combined with the universal synthesis of A2XF6:Mn4+ (A = K, Rb, Cs; X = Si, Ge), our findings can probably open up a simple and feasible green synthetic strategy for efficient Mn4+-doped fluorides using acidic salts.

2.
Dalton Trans ; 46(30): 9925-9933, 2017 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-28725900

RESUMO

Herein, a Mn4+ ion doped complex ternary-alkaline fluoride red phosphor K2NaAlF6:Mn4+ has been synthesized through a facile two-step co-precipitation method at room temperature. The crystal structure, morphological properties and influence of the dopant concentration, temperature and humidity on luminescence properties as well as the performance of the as-synthesized phosphor used in white light emitting diodes (WLEDs) were investigated carefully. Intense absorption in the blue region (∼460 nm) and bright narrow-band red emission (∼630 nm) with high color purity were observed from this resultant powder. Temperature-dependent investigation and reliability examination in a HTHH environment (85 °C high temperature and 85% high humidity) indicate that the obtained ternary-alkaline fluoride phosphor K2NaAlF6:Mn4+ presents more exceptional thermal quenching behavior and longevity compared to some other binary-alkaline fluorides. Moreover, using K2NaAlF6:Mn4+ as a red light component, a warm WLED with a preferable color rendering index (Ra = 85.5) and luminous efficacy (LE = 91.2 lm W-1) as well as a low corresponding color temperature (CCT = 3650 K) is easily achieved, further revealing the great potential of the as-prepared ternary-alkaline fluoride red phosphor K2NaAlF6:Mn4+ for WLED applications.

3.
Zhonghua Yu Fang Yi Xue Za Zhi ; 51(1): 65-69, 2017 Jan 06.
Artigo em Chinês | MEDLINE | ID: mdl-28056273

RESUMO

Objective: To determine the contribution of follow-up formula (FUF) to the nutrient intake of 7-24-month-old infants and young children. Methods: The cluster random sampling method and the convenience sampling method were used in combination, and geographic and economic factors were taken into consideration. Four areas of China (Beijing, Hebei, Guangxi, Guangdong) were selected, with 120 infants chosen from each of these areas (half of which were 7-12 months old, and half were 13-24 months old). A dietary survey was completed by a continuous 24-hour weighing method over two days. Questionnaires were completed by their caregivers which included weighing the FUF and supplementary food given to the infant, and recording the frequency of breast feeding and any supplementary nutrients. A total of 518 questionnaires were distributed, and 472 questionnaires qualified for inclusion. Nutrient intake was calculated using the China food composition, infant formula food nutrient content and infant nutrition supplement brand-label information databases, and then the nutrient intake proportion (the percentage of estimated energy requirement (EER%), recommended nutrient intake (RNI%) or adequate intake (AI%)), and the contribution rate of FUF were analyzed. Results: A total of 472 infants were investigated (227 infants aged 7-12 months old, 245 infants aged 13-24 months old). The findings revealed that the median energy intake of 7- 12-month-old and 13- 24-month-old infants were 2 530.08 kJ and 3 445.48 kJ, respectively, which accounted for 85.18% and 94.14% of EER, respectively; and the median intake of protein reached 91.50% and 105.88% of their RNI/AI, respectively. For micronutrients, the median intake of vitamin B1, vitamin B2, niacin, vitamin E, potassium, zinc and manganese in 7- 12-month-old infants and vitamin B2, vitamin E, potassium, magnesium, iron and manganese in 13-24-month-old children accounted for 82.00% and 114.29% of RNI/AI (RNI%/AI%), respectively. The intake of vitamin B6, iron and selenium in 7-12-month-old infants and vitamin B1, vitamin B6, vitamin C, calcium and selenium in 13-24-month-old children was less than 80% RNI/AI. Furthermore, some nutrients showed higher intake levels, such as vitamin A, calcium, phosphorus and magnesium in 7-12-month-old infants and vitamin A and phosphorus in 13-24-month-old children, which were higher than 130% RNI/AI. In total, 40.53% (92) of infants aged 7-12 months and 52.65% (129) of children aged 13- 24 months were fed FUF as part of their diet, and its contribution rate to macronutrients was 29.69% for carbohydrates and 51.77% for fats, and to micronutrients was 2.04% for manganese and 74.24% for vitamin C. Conclusion: FUF contributes to the nutrient intake of infants and young children aged from 7-24 months old at different rates depending on the macronutrient or micronutrient analyzed.


Assuntos
Inquéritos sobre Dietas , Ingestão de Energia , Comportamento Alimentar , Fórmulas Infantis , Pequim , Pré-Escolar , China , Dieta , Suplementos Nutricionais , Feminino , Seguimentos , Humanos , Lactente , Fenômenos Fisiológicos da Nutrição do Lactente , Masculino , Micronutrientes/administração & dosagem , Necessidades Nutricionais
4.
Zhonghua Yi Xue Za Zhi ; 96(20): 1597-601, 2016 May 31.
Artigo em Chinês | MEDLINE | ID: mdl-27266691

RESUMO

OBJECTIVE: To explore the effect of CD40 knock out on the cytotoxic function of CD8(+) T cell of mice with cigarette smoke-induced emphysema. METHODS: A total of 40 male C57 mice were divided into four groups according to the random number table, including CD40(+ /+) control group, CD40(+ /+) smoke-exposure group, CD40(-/-)control group, CD40(-/-)smoke-exposure group. The smoke-exposure groups were exposed to cigarette smoke for 24 weeks to establish emphysema model. Morphological changes were evaluated by linear intercepts. The percentages of CD8, perforin, granzyme B positive cells were evaluated by immunohistochemistry. The mRNA expressions of perforin, granzyme B, interleukin (IL) -27 were measured by fluorescent real time quantitative polymerase chain reaction (RT-PCR). The IL-27 cytokine level was tested by enzyme-linked immunosorbent assay (ELISA). RESULTS: The mean linear intercepts in CD40(+ /+) smoke-exposure group was significantly higher than CD40(+ /+) control group, CD40(-/-)control group, and CD40(-/-)smoke-exposure group [(37.2±3.6) vs (24.0±3.4), (22.5±2.4), (29.9±1.7) µm] (all P<0.05). CD40(-/-)smoke-exposure group was higher than CD40(+ /+) control group, CD40(-/-)control group (all P<0.05). The percentages of CD8 positive, perforin positive and granzyme B positive cells in CD40(+ /+) smoke-exposure group [(16.3±2.3)%, (11.4±2.1)%, (10.7±1.9)%] were significantly higher than CD40(+ /+) control group [(8.3±1.6)%, (5.1±1.2)%, (4.6±1.0)%], CD40(-/-)control group [ (6.4±1.5)%, (4.3±1.0)%, (4.2±1.0)%] and CD40(-/-)smoke-exposure group [(8.6±1.7)%, (5.6±1.3)%, (5.5±1.3)%] (all P<0.05). RT-PCR results showed that the mRNA expressions of perforin, granzyme B and IL-27 in CD40(+ /+) smoke-exposure group [(20.3±7.3), (18.3±12.3), (2.2±0.7)] were significantly higher than CD40(+ /+) control group [(9.4±4.8), (10.6±3.8), (1.3±0.6)], CD40(-/-)control group [ (8.1±3.1), (7.7±3.5), (1.1±0.5)] and CD40(-/-)smoke-exposure group [(12.9±6.2), (10.4±4.6), (1.5±0.4)] (all P<0.05). ELISA results showed that the level of IL-27 in CD40(+ /+) smoke-exposure group was significantly higher than CD40(+ /+) control group, CD40(-/-)control group and CD40(-/-)smoke-exposure group [(3 242±754) vs (1 627±710), (1 600±680), (1 850±583) ng/L] (all P<0.05). CONCLUSION: Knockout the CD40 gene can inhibit the cytotoxic effector function in CD8(+) T cells of mice with cigarette smoke-induced emphysema, and alleviate the degree of emphysema.


Assuntos
Antígenos CD40 , Linfócitos T CD8-Positivos/metabolismo , Enfisema Pulmonar/metabolismo , Fumaça/efeitos adversos , Fumar/efeitos adversos , Animais , Citocinas , Modelos Animais de Doenças , Enfisema , Ensaio de Imunoadsorção Enzimática , Granzimas , Interleucinas , Pulmão/fisiopatologia , Masculino , Camundongos , Camundongos Knockout , Enfisema Pulmonar/induzido quimicamente , RNA Mensageiro , Nicotiana
5.
Zhonghua Yi Xue Za Zhi ; 96(14): 1139-43, 2016 Apr 12.
Artigo em Chinês | MEDLINE | ID: mdl-27095786

RESUMO

OBJECTIVE: To evaluate the effect of CD40 on Foxp3(+) Treg cell in the lung of cigarette smoke exposure mice. METHODS: According to the random number table, 20 wild type (WT) C57 BL/6 mice and 20 CD40(-/-)C57 BL/6 mice were randomly divided into two groups: WT control group, WT smoke-exposure group (24 weeks) and CD40(-/-) control group, CD40(-/-) smoke-exposure group (24 weeks) (n=10 each). Alveolar airspace enlargement was observed by HE staining. Morphological change was evaluated by mean linear intercepts (MLI). Immunohistochemical method was used to detect the quantity of Foxp3(+) cell in the lung. The mRNA expression of Foxp3 was measured by fluorescence quantitative real-time polymerase chain reaction (qRT-PCR). The protein level of Foxp3 was measured by Western blot. Interleukin (IL)-10 and IL-35 levels in the lung were tested by enzyme-linked immunosorbent assay (ELISA). RESULTS: The MLI in CD40(-/-) smoke-exposure group was significantly lower than the WT smoke-exposure group[(30.0±1.7) vs (37.3±3.7) µm], but higher than the CD40(-/-) control group[(23.2±2.5) µm], WT smoke-exposure group was significantly higher than the WT control group[(22.2±1.7) µm](all P<0.05). The percentage of Foxp3(+) cell in the lungs of CD40(-/-) smoke-exposure group was significantly higher than the WT smoke-exposure group and CD40(-/-) control group[(16.89±0.75)% vs (9.65±0.74)% and (13.58±0.51)%], WT smoke-exposure group was significantly lower than WT control group[(12.13±0.81)%](all P<0.05). In the lungs, Foxp3 mRNA and protein expression in CD40(-/-) smoke-exposure group were increased compared to WT-smoke-exposure group and CD40(-/-) control group, WT smoke-exposure group were decreased compared to WT control group (all P<0.05). In the lungs, the level of IL-10 in CD40(-/-) smoke-exposure group was higher than the WT smoke-exposure group and CD40(-/-) control group[(231±25) vs (80±31) and (183±29) ng/L], WT smoke-exposure group was lower than the WT control group[(192±37) ng/L](all P<0.05). The level of IL-35 in CD40(-/-) smoke-exposure group was higher than the CD40(-/-) control group, WT control group and WT smoke-exposure group[(208±29) vs (118±29) , (148±36), (137±37) ng/L, all P<0.05]. CONCLUSION: Knockout the CD40 gene can promote the differentiation of Foxp3(+) Treg cell in the lung of cigarette smoke exposure mice, indicating that blocking the CD40-CD40 ligand pathway may contribute to alleviate the smoking-induced pulmonary emphysema.


Assuntos
Antígenos CD40 , Fatores de Transcrição Forkhead/genética , Enfisema Pulmonar/imunologia , Linfócitos T Reguladores , Poluição por Fumaça de Tabaco/efeitos adversos , Animais , Diferenciação Celular , Ensaio de Imunoadsorção Enzimática , Fatores de Transcrição Forkhead/metabolismo , Interleucina-10/sangue , Interleucina-10/metabolismo , Pulmão/fisiopatologia , Camundongos , Camundongos Knockout , Enfisema Pulmonar/induzido quimicamente , Enfisema Pulmonar/patologia , Distribuição Aleatória , Reação em Cadeia da Polimerase em Tempo Real , Fumaça , Fumar/efeitos adversos , Nicotiana
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