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1.
Adv Mater ; 35(8): e2208568, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36482821

RESUMO

Future electronic skin systems require stretchable conductors and low-temperature integration of external components, which remains challenging for traditional metal films. Herein, a bioinspired design concept is reported to endow metal films with 200% stretchability as well as room-temperature integration capability with diverse components. It is revealed that by controllable implantation of defects, distinctive venation-mimicking cracking modes can be induced in strained metal films, leading to profound stretchability regulation. An intriguing exponential-to-linear transition of the film electromechanical performance is observed, which is elucidated by a unified model covering the essence of all modes. Combined with room-temperature integration capability, an integrated electronic skin is constructed with metal films serving as stretchable electrodes, diverse sensors, and "tapes" to attach subcomponents, showing prospects in helping disabled people. This one-step, defect implantation strategy is applicable to common metals without special substrate treatments, which enables fascinating ultrastretchable metal film conductors with low-temperature integration capability to spark more sophisticated flexible electronic systems.

2.
Am J Chin Med ; 49(2): 461-485, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33641653

RESUMO

Traditional Chinese Medicine (TCM) is a practical medicine based on thousands of years of medical practice in China. Arsenic dispensing powder (ADP) has been used as a treatment for MDS patients with a superior efficacy on anemia at Xiyuan Hospital of China Academy of Chinese Medical Sciences. In this study, we retrospectively analyzed MDS patients that received ADP treatment in the past 9 years and confirmed that ADP improves patients' anemia and prolongs overall survival in intermediate-risk MDS patients. Then, we used the MDS transgenic mice model and cell line to explore the drug mechanism. In normal and MDS cells, ADP does not show cellular toxicity but promotes differentiation. In mouse MDS models, we observed that ADP showed significant efficacy on promoting erythropoiesis. In the BFU-E and CFU-E assays, ADP could promote erythropoiesis not only in normal clones but also in MDS clones. Mechanistically, we found that ADP could downregulate HIF1A in MDS clones through upregulation of VHL, P53 and MDM2, which is involved in two parallel pathways to downregulate HIF1A. We also confirmed that ADP upregulates GATA factors in normal clones. Thus, our clinical and experimental studies indicate that ADP is a promising drug to promote erythropoiesis in both MDS and normal clones with a superior outcome than current regular therapies. ADP promotes erythropoiesis in myelodysplastic syndromes via downregulation of HIF1A and upregulation of GATA factors.


Assuntos
Arsenicais/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Eritropoese/efeitos dos fármacos , Fatores de Transcrição GATA/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Síndromes Mielodisplásicas/tratamento farmacológico , Animais , Linhagem Celular , Regulação para Baixo , Humanos , Camundongos , Pós , Estudos Retrospectivos , Regulação para Cima
3.
Nanoscale ; 12(37): 19413-19419, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32955077

RESUMO

Silver (Ag)-based materials have shown great application potential in the oxygen reduction reaction (ORR) and hydrogen peroxide (H2O2) detection. The porous structures of Ag have attracted a lot of research interest due to their large specific surface area and high electrochemical activity. In this work, nanoporous Ag structures composed of nano-sized particles were prepared by a one-step pulsed laser deposition (PLD) under controlled background gas pressure. The porous PLD-Ag showed a high ORR performance (Eonset: 1.007 V vs. RHE, E1/2: 0.863 V vs. RHE), high sensitivity (613.1 µA cm-2 mM-1 at -0.2 V vs. SCE) and selectivity for H2O2 detection. The PLD technique provided a new, yet universal approach to producing high-performance, metal-based electrochemical electrodes.

4.
ACS Appl Mater Interfaces ; 12(14): 16743-16752, 2020 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-32174102

RESUMO

Ag-Cu bimetallic nanoparticles, combining the advantages of both Ag and Cu, are a promising material for power electronic packaging. In this work, a supersaturated Ag-7.3 wt % Cu alloy nanoparticle film was developed by using pulsed laser deposition. Unlike Cu nanoparticles, the supersaturated Ag-Cu alloy nanoparticles can conduct bonding in air without the assistance of a reduction agent. The shear strength was >20 MPa when the bonding temperature reached 300 °C, which was above the die shear standard (MIL-STD-883 K, 7.8 MPa) and compatible with the typical die attach process. The Cu separating behavior was accompanied by the bonding process at 250-400 °C, which was discussed systematically. Neck formation was delayed to about 250 °C because of the hindering effect of the thin oxide shell of the Ag-Cu alloy. The necking networks provide volume diffusion paths despite the growth of surface oxide, resulting in compact densification. The bondline under the SiC die consisted of a porous Ag-Cu alloy matrix with a dispersed secondary phase of Cu2O/CuO, which is supposed to have improved electrochemical migration resistance.

5.
Chin J Integr Med ; 25(6): 409-415, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29619748

RESUMO

OBJECTIVES: To investigate the relationship between gene mutations and response to Compound Qinghuang Powder (, CQHP) in patients with myelodysplastic syndrome (MDS). METHODS: Forty-three MDS patients were genotyped by ultra-deep targeted sequencing and the clinical data of patients were collected and the relationship between them was analyzed. RESULTS: Up to 41.86% of patients harbored genet mutations, in most cases with more than one mutation. The most common mutations were in SF3B1, U2AF1, ASXL1, and DNMT3A. After treatment with CQHP, about 88.00% of patients no longer required blood transfusion, or needed half of prior transfusions. CONCLUSIONS: CQHP is an effective treatment for patients with MDS, especially those with gene mutations in SF3B1, DNMT3A, U2AF1, and/or ASXL1.


Assuntos
Arsênio/uso terapêutico , Arsenicais/uso terapêutico , Medicamentos de Ervas Chinesas/uso terapêutico , Estudos de Associação Genética , Mutação/genética , Síndromes Mielodisplásicas/tratamento farmacológico , Síndromes Mielodisplásicas/genética , Adulto , Transfusão de Sangue , Feminino , Humanos , Cariótipo , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
6.
ACS Appl Mater Interfaces ; 11(18): 16972-16980, 2019 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-30945537

RESUMO

Decreasing the interconnecting temperature is essential for 3D and heterogeneous device integrations, which play indispensable roles in the coming era of "more than Moore". Although nanomaterials exhibit a decreased onset temperature for interconnecting, such an effect is always deeply impaired because of organic additives in practical integrations. Meanwhile, current organic-free integration strategies suffer from roughness and contaminants at the bonding interface. Herein, a novel bilayer nanoarchitecture simultaneously overcomes the drawbacks of organics and is highly tolerant to interfacial morphology, which exhibits universal applicability for device-level integrations at even room temperature, with the overall performance outperforming most counterparts reported. This nanoarchitecture features a loose nanoparticle layer with unprecedented deformability for interfacial gap-filling, and a compact one providing firm bonding with the component surface. The two distinct nanoparticle layers cooperatively enhance the interconnecting performance by 73-357%. Apart from the absence of organics, the internal abundant lattice disorders profoundly accelerate the interconnecting process, which is supported by experiments and molecular dynamics simulation. This nanoarchitecture is successfully demonstrated in diversified applications including paper-based light-emitting diodes, Cu-Cu micro-bonding, and SiC power modules. The strategy proposed here can open a new paradigm for device integrations and provide a fresh understanding on interconnecting mechanisms.

7.
Chin J Integr Med ; 25(7): 497-501, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31278627

RESUMO

OBJECTIVE: To investigate the relation of blood arsenic concentration (BAC) with clinical effect and safety of arsenic-containing Qinghuang Powder (, QHP) in patients with myelodysplastic syndrome (MDS). METHODS: Totally 163 patients with MDS were orally treated with QHP for 2 courses of treatment, 3 months as 1 course. The BACs of patients were detected by atomic fluorescence spectrophotometry at 1, 3, and 6 months during the treatment, and the effective rate, hematological improvement and safety in patients after treatment with QHP were analyzed. RESULTS: After 2 courses of treatment, the total effective rate was 89.6% (146/163), with 31.3% (51/163) of hematological improvement and 58.3% (95/163) of stable disease. The hemoglobin increased from 73.48 ± 19.30 g/L to 80.39 ± 26.56 g/L (P<0.05), the absolute neutrophil count increased from 0.81 ± 0.48 × 109/L to 1.08 ± 0.62 × 109/L (P<0.05), and no significant changes were observed in platelet counts (P>0.05). Among 46 patients previously depended on blood transfusion, 28.3% (13/46) completely got rid of blood transfusion and 21.7% (10/46) reduced the volume of blood transfusion by more than 50% after treatment. The BACs were significantly increased in patients treated for 1 month with 32.17 ± 18.04 µ g/L (P<0.05), 3 months with 33.56 ± 15.28 µ g/L (P<0.05), and 6 months with 36.78 ± 11.92 µ g/L (P<0.05), respectively, as compared with those before treatment (4.08 ± 2.11 µ g/L). There were no significant differences of BACs among the patients treated for 1, 3 and 6 months (P>0.05). The adverse reactions of digestive tract during the treatment were mild abdominal pain and diarrhea in 14 cases (8.6%), and no patients discontinued the treatment. The BACs of patients with gastrointestinal adverse reactions were significantly lower than those without gastrointestinal adverse reactions (22.39 ± 10.38 vs. 37.89 ± 11.84, µ g/L, P<0.05). The BACs of patients with clinical effect were significantly higher than those failed to treatment (40.41 ± 11.69 vs. 23.84 ± 12.03, µ g/L, P<0.05). CONCLUSION: QHP was effective and safe in the treatment of patients with MDS and the effect was associated with BACs of patients.


Assuntos
Arsênio/sangue , Arsenicais/efeitos adversos , Arsenicais/uso terapêutico , Medicamentos de Ervas Chinesas/efeitos adversos , Medicamentos de Ervas Chinesas/uso terapêutico , Síndromes Mielodisplásicas/sangue , Síndromes Mielodisplásicas/tratamento farmacológico , Contagem de Células Sanguíneas , Transfusão de Sangue , Humanos , Cariótipo , Pós , Fatores de Risco
8.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 26(2): 522-527, 2018 Apr.
Artigo em Zh | MEDLINE | ID: mdl-29665926

RESUMO

OBJECTIVE: To analyze the imbalance of pro-inflammatory and anti-inflammatory cytokines in the patients of immune thrombocytopenia (ITP). METHODS: Thirty-five patients with ITP were enrolled in ITP group, while 28 healthy persons were included in control group. The expressions of IL-8, IL-17A, IL-22, TNF-α, IFN-γ, IL-4, CD40, CD40L, TGF-ß and IL-10 were detected by flow cytometry with aimPlex multiple immunoassay Flow. RESULTS: The expressions of pro-inflammatory factors IL-8, IL-17A, IL-22, IFN-γ and TNF-α in ITP group all were significantly higher than that in the control group (P<0.05), however the expressions of anti-inflammatory factors IL-4, CD40L, TGF-ß and IL-10 in ITP group all were significantly lower than that in the control group (P<0.05). The expression of CD40 was not significantly different between ITP group and control group (P>0.05). Expressions of TNF-α significantly related with platelet counts in both ITP group and control group (ITP group, r=0.64, P<0.05; control group, r=-0.41, P<0.05). However the expression of CD40, TGF-ß, CD40L, IL-8, IL-17A, IL-22, IL-10, IL-1ß, IFN-γ and IL-4 significantly did not relate with platelet counts in both ITP and control group. CONCLUSIONS: The secretory imbalance between pro-inflammatory and anti-inflammatory cytokines exists in the patients of ITP. The decrease of Plt regulated may be regulated by the abnormal expression of TNF-α.


Assuntos
Púrpura Trombocitopênica Idiopática , Citocinas , Humanos
9.
Artigo em Inglês | MEDLINE | ID: mdl-29348764

RESUMO

OBJECTIVE: To establish the clinical safe and effective methods of arsenic-containing compound-Qinghuang Powder (compound-QHP) in the treatment of myelodysplastic syndrome (MDS). METHODS: 200 patients with MDS were treated with compound-QHP (daily dose of 0.1 g realgar). The blood arsenic concentrations (BACs) were detected by atomic fluorescence spectrophotometry (HF-AFS). After treatment for 1 month, the patients were randomly divided into group A and group B when the BACs were less than 20 µg/L. Daily dose of realgar was maintained in group A and it was increased to that when the BACs were more than 20 µg/L in group B. The BAC and clinical efficacy and safety in two groups were compared at the end of the treatment with compound-QHP. RESULTS: The average BAC of group B was significantly higher than that of group A (P < 0.01). The rates of hematology improvement and reduced transfusion were significantly higher in group B than in group A (P < 0.05). The HGB, ANC, and PLT significantly increased in group B after treatment (P > 0.05). CONCLUSIONS: Monitoring the BAC and adjusting the daily dose of realgar to increase the effective BAC and then improving efficacy without increasing the clinical toxicity are the clinical safe and effective methods in the treatment of MDS.

10.
Bioresour Technol ; 162: 115-22, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24747389

RESUMO

To evaluate the potential of Chlorococcum pamirum for producing biodiesel, the effects of nitrogen, phosphate, initial cell concentrations and NaCl on lipid accumulation and growth were studied. The highest specific growth rate (µ(max)), biomass productivity and lipid content achieved was 1.888 d(-1), 350.1 mg L(-1) day(-1), and 64.9%, respectively. Under nitrogen-deficient condition, the cells accumulated lipids faster at low initial cell concentration. Additional NaCl to nitrogen-deficient media accelerated the lipid accumulation. When adding 10 g L(-1) NaCl to nitrogen-deficient media, the lipid content and productivity of cells cultured outdoors with high initial cell concentration increased from 38.2% and 153 mg L(-1) day(-1) to 54.3% and 192 mg L(-1) day(-1) respectively. Moreover, NaCl enhanced the saturated fatty acids content from 56.40% to 73.41% of total fatty acids. The results show that C. pamirum is a promising organism for biofuel production.


Assuntos
Biocombustíveis , Clorófitas/metabolismo , Biomassa , Reatores Biológicos/microbiologia , Clorófitas/citologia , Clorófitas/efeitos dos fármacos , Clorófitas/crescimento & desenvolvimento , Lipídeos/biossíntese , Nitratos/farmacologia , Nitrogênio/farmacologia , Fosfatos/farmacologia , Fósforo/farmacologia , Compostos de Potássio/farmacologia , Cloreto de Sódio/farmacologia
11.
J Agric Food Chem ; 61(19): 4639-45, 2013 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-23614832

RESUMO

Oil-in-water (O/W) emulsions have been used as a delivery system to protect conjugated linoleic acid (CLA), a polyunsaturated fatty acid, from oxidation. Conventional gum arabic (GA) and two matured gum arabic samples (EM2 and EM10) were used as emulsifiers to prepare CLA-in-water emulsions. The emulsions have optimal physical and chemical stability at gum concentrations of 5% for all three gums. Emulsions with higher gum concentrations are more susceptible to lipid oxidation. This is attributed to reduced physical stability at higher gum concentrations because of the coalescence and depletion-induced flocculation of the emulsion droplets. The prooxidants iron and copper intrinsically contained in the gums could also contribute to this instability. Among the three gums, EM10 provides the most effective protection for CLA both physically and chemically, because of its superior interfacial properties over GA and EM2.


Assuntos
Fenômenos Químicos , Goma Arábica/química , Ácidos Linoleicos Conjugados/química , Cobre/química , Estabilidade de Medicamentos , Emulsificantes/química , Emulsões/química , Ferro/química , Microscopia , Oxirredução , Tamanho da Partícula , Água/química
12.
J Biosci Bioeng ; 114(4): 405-10, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22698727

RESUMO

To evaluate the potential of the green agla Chlorella zofingiensis as a feedstock for biodiesel production, the effects of nitrogen and phosphate on lipid accumulation and growth of C. zofingiensis were studied. The maximum specific growth rate (µ(max)) reached 2.15 day⁻¹ when the concentration of NaNO3 and K2HPO4·3H2O was 1.0 g L⁻¹ and 0.01 g L⁻¹, respectively. The lipid contents of C. zofingiensis grown in media deficient of nitrogen (65.1%) or phosphate (44.7%) were both higher than that obtained from cells grown in full medium (33.5%). The highest lipid productivity (87.1 mg L⁻¹ day⁻¹) was also obtained from cells grown in nitrogen deficient media, indicating nitrogen deficiency was more effective than phosphate deficiency for inducing lipid accumulation in C. zofingiensis. In addition, the feasibility of cultivating the alga in 60 L flat plate photobioreactors and 10 L bottles outdoors for biodiesel was also tested. It was found that C. zofingiensis could adapt to fluctuating temperatures and irradiance of outdoors and the highest µ(max) and lipid productivity could reach 0.362 day⁻¹ and 26.6 mg L⁻¹ day⁻¹ outdoors, respectively. The lipid production potential of C. zofingiensis is projected to be 31.1 kg ha⁻¹ day⁻¹ in outdoor culture. These results suggested that C. zofingiensis is a promising organism for feedstock production of biofuel and can be used in scaled up culture outdoors.


Assuntos
Biocombustíveis , Chlorella/crescimento & desenvolvimento , Processos Autotróficos , Chlorella/metabolismo , Luz , Lipídeos/biossíntese , Nitratos/metabolismo , Nitrogênio/metabolismo , Fosfatos/metabolismo , Fotobiorreatores , Compostos de Potássio/metabolismo , Temperatura
13.
Bioresour Technol ; 102(22): 10577-84, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21955881

RESUMO

Culturing microalgae using natural sunlight is an effective way to reduce the cost of microalgae-based biodiesel production. In order to evaluate the feasibility of culturing Chlorella zofingiensis outdoors for biodiesel production, effects of nitrogen limitation and initial cell concentration on growth and lipid accumulation of this alga were investigated in 60 L flat plate photobioreactors outdoors. The highest µmax and biomass productivity obtained was 0.994 day(-1) and 58.4 mg L(-1)day(-1), respectively. The lipid content was much higher (54.5% of dry weight) under nitrogen limiting condition than under nitrogen sufficient condition (27.3%). With the increasing initial cell concentrations, the lipid contents declined, while lipid concentrations and productivities increased. The highest lipid content, lipid concentration, and lipid productivity obtained was 54.5%, 536 mg L(-1) and 22.3 mg L(-1)day(-1), respectively. This study demonstrated that it was possible to culture C. zofingiensis under outdoor conditions for producing biodiesel feedstock.


Assuntos
Biotecnologia/instrumentação , Chlorella/crescimento & desenvolvimento , Chlorella/metabolismo , Metabolismo dos Lipídeos , Fotobiorreatores , Biomassa , Chlorella/efeitos dos fármacos , Chlorella/efeitos da radiação , Cinética , Luz , Metabolismo dos Lipídeos/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos da radiação , Nitrogênio/farmacologia , Temperatura
14.
Biotechnol Lett ; 30(10): 1741-6, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18661109

RESUMO

Nostoc sphaeroides Kützing was cultivated in paddlewheel-driven raceway ponds and the growth kinetics of 1-2 mm and 3-4 mm colonies of N. sphaeroides was studied. The biomass productivities in 2.5 m(2) raceway ponds inoculated with 1-2 mm and 3-4 mm colonies were 5.2 and 0.25 g dry wt m(-2) d(-1), respectively. Furthermore, differently sized colonies showed different relative water content, total soluble carbohydrates, chlorophyll a content and density of filaments. This is the first report on mass culture of N. sphaeroides under outdoor conditions.


Assuntos
Nostoc/crescimento & desenvolvimento , Biomassa , Cinética
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