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1.
Small ; 20(16): e2306989, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38032164

RESUMO

Hybrid organic-inorganic perovskite (HOIP) ferroelectric materials have great potential for developing self-powered electronic transducers owing to their impressive piezoelectric performance, structural tunability and low processing temperatures. Nevertheless, their inherent brittle and low elastic moduli limit their application in electromechanical conversion. Integration of HOIP ferroelectrics and soft polymers is a promising solution. In this work, a hybrid organic-inorganic rare-earth double perovskite ferroelectric, [RM3HQ]2RbPr(NO3)6 (RM3HQ = (R)-N-methyl-3-hydroxylquinuclidinium) is presented, which possesses multiaxial nature, ferroelasticity and satisfactory piezoelectric properties, including piezoelectric charge coefficient (d33) of 102.3 pC N-1 and piezoelectric voltage coefficient (g33) of 680 × 10-3 V m N-1. The piezoelectric generators (PEG) based on composite films of [RM3HQ]2RbPr(NO3)6@polyurethane (PU) can generate an open-circuit voltage (Voc) of 30 V and short-circuit current (Isc) of 18 µA, representing one of the state-of-the-art PEGs to date. This work has promoted the exploration of new HOIP ferroelectrics and their development of applications in electromechanical conversion devices.

2.
Dalton Trans ; 52(44): 16406-16412, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37870776

RESUMO

Organic-inorganic hybrid perovskites (OIHPs) with dielectric switching functions have aroused comprehensive scientific interest, benefitting from their promising applications in sensors and information storage. However, to date, most of these materials discovered thus far possess a single function and are limited in their applicability, failing to meet the requirements of diverse applications. Moreover, the discovery of these materials has been largely serendipitous. Building multifunctional OIHPs with dielectric switching and semiconductors remains a daunting task. In this context, by introducing [C7H16N]+ as cations and in combination with lead halide with semiconducting properties, two OIHPs [C7H16N]PbI3 (1) and [C7H16N]PbBr3 (2) ([C7H16N]+ = (cyclopropylmethyl) trimethylammonium) have been successfully designed. They have dielectric switching properties close to 253 and 279 K and semiconducting behavior with band gaps of 2.67 and 3.22 eV. The phase transition temperature increased by 26 K through halogen substitution. In summary, our findings in this study provide insights into the application of the halogen substitution regulation strategy and open up new possibilities for designing perovskite semiconductors with dielectric switching functionality.

3.
World J Clin Cases ; 10(10): 3232-3240, 2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35647137

RESUMO

BACKGROUND: IgA nephropathy (IgAN) is a common primary glomerular disease that leads to end-stage renal disease with poor therapy efficacy. Traditional Chinese medicine (TCM) is effective in the treatment of IgAN and has the potential to become an alternative treatment for IgAN. Professor Yan-Qin Zou is a nephropathy expert, a National Chinese Medicine Master, and an heir to the Menghe School of Medicine. CASE SUMMARY: A 28-year-old man had positive urinary protein and elevated serum creatinine (Scr) results and was diagnosed with IgAN 2-3 years prior to the outpatient department visit at our hospital in 2017. Professor Zou used the following methods to treat the patient: Invigorating the spleen and tonifying the kidney, removing dampness and clearing turbidity, quickening the blood and transforming stasis, and freeing vessels and regulating collaterals. She adjusted the prescription in accordance with the patient's symptoms. After 6 mo of treatment, the symptoms had resolved and serological indexes were also decreased [Scr from 288.5 to 188.6 µmol/L, blood urea nitrogen (BUN) from 10.9 to 9.5 mmol/L, serum uric acid (UA) from 612 to 503 µmol/L]. During follow-up, BUN, Scr, and UA levels remained stable. CONCLUSION: Professor Zou's therapeutic strategy to treat IgAN using TCM was efficacious and a good reference for application.

4.
Orthop Surg ; 11(6): 923-931, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31823499

RESUMO

To compare the effectiveness and safety of dynamic fixation (DF) and static fixation (SF) in distal tibiofibular syndesmosis injuries (DTSI) by a system review and meta-analysis. PubMed, Cochrane, and EMBASE were systematically searched by computer to select clinical randomized controlled trials (RCT) and cohort trials comparing DF and SF in treating patients with DTSI. RCT and cohort trials comparing DF and SF for patients with DTSI were included. Inclusion criteria: (i) prospective or retrospective study of patients with DTSI; (ii) patients were diagnosed as having DTSI by imageology and only received DF treatment or SF treatment; (iii) the study compared DF and SF in DTSI; and (iv) one or more of the following outcomes were reported: ankle joint functional score, surgical complications, malreduction of syndesmosis, and second operations. Exclusion criteria: (i) non-human studies; (ii) DTSI patients accompanied with other complications or other joints injuries; and (iii) full text unavailable. RevMan V5.3 software was used to perform the statistical analysis. Outcomes analyzed by Revman software showed that there were no statistically significant differences between DF and SF in the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score (MD, 1.90; 95% CI, -0.23 to 4.03; P = 0.08; I2 = 0%), Olerud-Molander (OM) score (MD, 1.92; 95% CI, -7.96 to 11.81; P = 0.70; I2 = 55%), incidence of syndesmotic malreduction (RR, 0.19; 95% CI, 0.03 to 1.09; P = 0.06; I2 = 0%), and overall postoperative complication rate (RR, 0.30; 95% CI, 0.09 to 0.99; P = 0.05, I2 = 75%) and the rate of second procedure was significantly lower with DF (RR, 0.17; 95% CI, 0.07 to 0.43; P = 0.0002, I2 = 54%). Compared to SF, DF has an advantage, with a low rate of second procedures to treat DTSI.


Assuntos
Traumatismos do Tornozelo/cirurgia , Fixação Interna de Fraturas/métodos , Instabilidade Articular/cirurgia , Parafusos Ósseos , Avaliação da Deficiência , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Técnicas de Sutura , Resultado do Tratamento
5.
Science ; 360(6393): 1087-1092, 2018 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-29880681

RESUMO

A high concentration of low-density lipoprotein cholesterol (LDL-C) is a major risk factor for cardiovascular disease. Although LDL-C levels vary among humans and are heritable, the genetic factors affecting LDL-C are not fully characterized. We identified a rare frameshift variant in the LIMA1 (also known as EPLIN or SREBP3) gene from a Chinese family of Kazakh ethnicity with inherited low LDL-C and reduced cholesterol absorption. In a mouse model, LIMA1 was mainly expressed in the small intestine and localized on the brush border membrane. LIMA1 bridged NPC1L1, an essential protein for cholesterol absorption, to a transportation complex containing myosin Vb and facilitated cholesterol uptake. Similar to the human phenotype, Lima1-deficient mice displayed reduced cholesterol absorption and were resistant to diet-induced hypercholesterolemia. Through our study of both mice and humans, we identify LIMA1 as a key protein regulating intestinal cholesterol absorption.


Assuntos
Povo Asiático/genética , LDL-Colesterol/metabolismo , Proteínas do Citoesqueleto/metabolismo , Mutação da Fase de Leitura , Absorção Intestinal/genética , Mucosa Intestinal/metabolismo , Animais , China , LDL-Colesterol/sangue , Proteínas do Citoesqueleto/genética , Variação Genética , Células Hep G2 , Humanos , Cazaquistão/etnologia , Proteínas de Membrana/metabolismo , Proteínas de Membrana Transportadoras , Camundongos , Camundongos Knockout , Cadeias Pesadas de Miosina/metabolismo , Miosina Tipo V/metabolismo , Linhagem , Ligação Proteica , Transporte Proteico
6.
Cell Rep ; 19(13): 2823-2835, 2017 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-28658628

RESUMO

Proper intracellular cholesterol trafficking is critical for cellular function. Two lysosome-resident proteins, NPC1 and NPC2, mediate the egress of low-density lipoprotein-derived cholesterol from lysosomes. However, other proteins involved in this process remain largely unknown. Through amphotericin B-based selection, we isolated two cholesterol transport-defective cell lines. Subsequent whole-transcriptome-sequencing analysis revealed two cell lines bearing the same mutation in the vacuolar protein sorting 53 (Vps53) gene. Depletion of VPS53 or other subunits of the Golgi-associated retrograde protein (GARP) complex impaired NPC2 sorting to lysosomes and caused cholesterol accumulation. GARP deficiency blocked the retrieval of the cation-independent mannose 6-phosphate receptor (CI-MPR) to the trans-Golgi network. Further, Vps54 mutant mice displayed reduced cellular NPC2 protein levels and increased cholesterol accumulation, underscoring the physiological role of the GARP complex in cholesterol transport. We conclude that the GARP complex contributes to intracellular cholesterol transport by targeting NPC2 to lysosomes in a CI-MPR-dependent manner.


Assuntos
Colesterol/metabolismo , Lisossomos/metabolismo , Proteínas de Membrana/genética , Proteínas de Transporte Vesicular/metabolismo , Animais , Transporte Biológico , Humanos , Proteínas de Membrana/metabolismo , Camundongos
7.
Int J Med Mushrooms ; 17(1): 33-41, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25746404

RESUMO

In this study, the compositions of Ophiocordyceps longissima mycelia, synnemata, and fruiting bodies were first analyzed in order to clarify its chemical basis for development as a health food or medicine. We found that the contents of crude protein, polysaccharides, and macroelements were highest in mycelia, whereas effective components, including mannitol, ergosterol, adenosine, inosine, Zn, and Se, were lowest in mycelia. Polysaccharide, mannitol, and ergosterol levels in synnemata (2.33, 4.54, and 0.66 g/100 g, respectively) were similar to those in fruiting bodies, but was significantly different from those of mycelia (4.79, 1.77, and 0.43 g/100 g). Trehalose content in fruiting bodies (2.15 g/100 g) was >4 times higher than that in synnemata (0.5 g/100 g). Adenosine content in fruiting bodies (0.024 g/100 g) was 3-4 times higher than that of synnemata, whereas inosine, cytosine, guanosine, and uridine (0.093, 0.145, 0.053, and 0.073 g/100 g) were highest in synnemata. Cu and Se were lower in mycelia (3.30 × 10⁻4 and 3.1 × 10⁻5 g/100 g) than in synnemata (1.85 × 10⁻³ and 7.2 × 10⁻5 g/100 g) and fruiting bodies (1.67 × 10⁻³ and 4.3 × 10⁻5 g/100 g). As, Hg, Cd, and Pb in mycelia were under the limit of edible fungus health standard; Pb was not found, but Cd, Hg, and As were detected in fruiting bodies. These findings suggest that O. longissima could be utilized in different culture methods according to market demand and might be a possible health food or medicinal resource.


Assuntos
Hypocreales/química , Extratos Vegetais/análise , Cobre/análise , Carpóforos/química , Carpóforos/crescimento & desenvolvimento , Hypocreales/crescimento & desenvolvimento , Micélio/química , Micélio/crescimento & desenvolvimento , Valor Nutritivo , Proteínas de Plantas/análise , Polissacarídeos/análise
8.
J Pharmacol Exp Ther ; 352(1): 166-74, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25378375

RESUMO

It has been reported that ophiopogonin D (OP-D), a steroidal glycoside and an active component extracted from Ophiopogon japonicas, promotes antioxidative protection of the cardiovascular system. However, it is unknown whether OP-D exerts protective effects against doxorubicin (DOX)-induced autophagic cardiomyocyte injury. Here, we demonstrate that DOX induced excessive autophagy through the generation of reactive oxygen species (ROS) in H9c2 cells and in mouse hearts, which was indicated by a significant increase in the number of autophagic vacuoles, LC3-II/LC3-I ratio, and upregulation of the expression of GFP-LC3. Pretreatment with OP-D partially attenuated the above phenomena, similar to the effects of treatment with 3-methyladenine. In addition, OP-D treatment significantly relieved the disruption of the mitochondrial membrane potential by antioxidative effects through downregulating the expression of both phosphorylated c-Jun N-terminal kinase and extracellular signal-regulated kinase. The ability of OP-D to reduce the generation of ROS due to mitochondrial damage and, consequently, to inhibit autophagic activity partially accounts for its protective effects in the hearts against DOX-induced toxicity.


Assuntos
Autofagia/efeitos dos fármacos , Citoproteção/efeitos dos fármacos , Doxorrubicina/efeitos adversos , Mitocôndrias/efeitos dos fármacos , Saponinas/farmacologia , Espirostanos/farmacologia , Animais , Regulação para Baixo/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Mitocôndrias/metabolismo , Miócitos Cardíacos/citologia , Miócitos Cardíacos/efeitos dos fármacos , Ratos , Espécies Reativas de Oxigênio/metabolismo
9.
Yao Xue Xue Bao ; 49(8): 1117-23, 2014 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-25322552

RESUMO

This study aimed to examine whether ophiopogonin D (OP-D) is capable of protecting cardiomyocytes against DOX-induced injury and the mechanisms involved. H9c2 cells were cultured. MTT assay was used to evaluate cell viability and toxicity. Mito-tracker as fluorescence probe was used to measure ROS content raised from mitochondria. The mRNA and protein expression of ATF6alpha, GRP78 and CHOP were analyzed using real-time PCR and Western blotting, respectively. The results showed that a significant endoplasmic reticulum stress (ERS) was induced upon exposure of H9c2 cells to DOX as indicated by the increase in the expression of ERS related proteins, which was paralleled with the accumulation of reactive oxygen species (ROS) and decrease in the viability of H9c2 cells. Whereas, DOX-induced ROS accumulation and up-regulation of ERS related proteins were partially abolished by pretreatment with OP-D. Consequently, a DOX-induced ERS was mitigated by application of OP-D. Similarly, DOX-induced decrease in cell viability was partially attenuated by either inhibiting CHOP or pretreatment with N-acetylcysteine (NAC), an antioxidant. Moreover, cardiac ultrastructural abnormalities seen in mouse receiving DOX injections were obviously ameliorated by pretreatment of OP-D. Taken together, the present study proved that OP-D protects cardiomyocytes against DOX-induced injury, at least in part, through reducing ROS accumulation and alleviating ERS.


Assuntos
Doxorrubicina/efeitos adversos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Saponinas/farmacologia , Espirostanos/farmacologia , Acetilcisteína , Fator 6 Ativador da Transcrição/metabolismo , Animais , Antioxidantes , Linhagem Celular , Sobrevivência Celular , Chaperona BiP do Retículo Endoplasmático , Proteínas de Choque Térmico/metabolismo , Camundongos , Mitocôndrias/metabolismo , Ratos , Espécies Reativas de Oxigênio/metabolismo , Fator de Transcrição CHOP/metabolismo , Regulação para Cima
10.
Nat Med ; 20(1): 80-6, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24336247

RESUMO

Hypercholesterolemia, typically due to excessive cholesterol uptake, is a major risk factor for cardiovascular disease, which is responsible for ∼50% of all deaths in developed societies. Although it has been shown that intestinal cholesterol absorption is mediated by vesicular endocytosis of the Niemann-Pick C1-like 1 (NPC1L1) protein, the mechanism of sterol-stimulated NPC1L1 internalization is still mysterious. Here, we identified an endocytic peptide signal, YVNXXF (where X stands for any amino acid), in the cytoplasmic C-terminal tail of NPC1L1. Cholesterol binding on the N-terminal domain of NPC1L1 released the YVNXXF-containing region of NPC1L1 from association with the plasma membrane and enabled Numb binding. We also found that Numb, a clathrin adaptor, specifically recognized this motif and recruited clathrin for internalization. Disrupting the NPC1L1-Numb interaction decreased cholesterol uptake. Ablation of Numb in mouse intestine significantly reduced dietary cholesterol absorption and plasma cholesterol level. Together, these data show that Numb is a pivotal protein for intestinal cholesterol absorption and may provide a therapeutic target for hypercholesterolemia.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Colesterol/metabolismo , Hipercolesterolemia/fisiopatologia , Absorção Intestinal/fisiologia , Proteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/fisiologia , Análise de Variância , Animais , Linhagem Celular Tumoral , Fluorescência , Transferência Ressonante de Energia de Fluorescência , Humanos , Immunoblotting , Proteínas de Membrana/fisiologia , Proteínas de Membrana Transportadoras/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Proteínas do Tecido Nervoso/fisiologia , Interferência de RNA , RNA Interferente Pequeno/genética , Ratos , Técnicas do Sistema de Duplo-Híbrido
11.
Cell Stress Chaperones ; 16(3): 287-96, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21080136

RESUMO

It has been reported that pretreatment of rats with lipopolysaccharide (LPS) increases myocardial functional recovery in ischemia/reperfusion (I/R) hearts. However, the mechanisms by which LPS induces cardioprotection against I/R injury have not been fully elucidated. In this study, we pretreated rats with LPS (1.0 mg/kg) 24 h before they were subjected to I/R injury, and then examined the roles of heat shock protein-70 (HSP70) and nucleus factor-κB (NF-κB) in LPS-induced cardioprotection. We observed that pretreatment with low-dose LPS resulted in significantly increased levels of HSP70 in the myocardium, which could dramatically inhibit NF-κB translocation and reduce degradation of inhibitory κB. Inhibition of NF-κB, in turn, attenuated release of inflammatory cytokines (tumor necrosis factor-α, interleukin (IL)-1ß, and IL-6) and reduced apoptosis of myocardium and infarct area following I/R injury. Moreover, HSP70 could ameliorate oxidative stress following I/R injury. To further investigate whether increase of HSP70 might be responsible for protection of the myocardium against I/R injury, we co-administered the HSP70 inhibitor, quercetin, with LPS before I/R injury. We found that LPS-induced cardioprotection was attenuated by co-administration with quercetin. Herein, we concluded that increased levels of HSP70 through LPS pretreatment led to inhibition of NF-κB activity in the myocardium after I/R injury. Our results indicated that LPS-induced cardioprotection was mediated partly through inhibition of NF-κB via increase of HSP70, and LPS pretreatment could provide a means of reducing myocardial I/R injury.


Assuntos
Proteínas de Choque Térmico HSP70/metabolismo , Lipopolissacarídeos/farmacologia , NF-kappa B/antagonistas & inibidores , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/prevenção & controle , Animais , Apoptose/efeitos dos fármacos , Proteínas I-kappa B/metabolismo , Inflamação/complicações , Inflamação/patologia , Masculino , Miocárdio/patologia , NF-kappa B/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Ratos , Ratos Wistar , Traumatismo por Reperfusão/complicações , Traumatismo por Reperfusão/patologia
12.
Biorheology ; 45(5): 587-98, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19065007

RESUMO

There is evidence that hyperlipidemia can induce hemorheological and microcirculatory disturbances. Myakuryu, a Chinese traditional medicine is efficacious in promoting lipid metabolism and protecting oxidative stress, but whether this drug can ameliorate rheologic disturbances caused by hyperlipidemia is still unknown. The present study was conducted to investigate the effects of myakuryu on hemorheological and microcirculatory disturbances induced by hyperlipidemia. Wistar rats were divided into a group on control diet (n=8) and a group on high-fat diet (HFD, n=44). Eight weeks later, plasma triglyceride (TG) and total cholesterol (TC) were determined. Sixteen animals with the highest levels of hyperlipidemia from the HFD group were randomly divided into two sub-groups: the untreated hyperlipidemia group (n=8) and the group treated with myakuryu (n=8). At the end of the sixteenth week, rheological and microcirculatory parameters were measured. Chemical analysis showed that myakuryu treatment caused significant reductions of plasma TG and TC levels (P<0.01), and the cholesterol/phospholipid ratio in the erythrocyte membrane (P<0.05). Rheological and microcirculatory measurements showed that myakuryu treatment led to a significant decrease in the erythrocyte aggregation index, plasma viscosity and blood viscosity at shear rates of 50, 100 and 150 s(-1) and in adherent leukocytes in mesenteric venules. There was a significant increase in erythrocyte deformation, electrophoretic mobility, membrane fluidity and F-actin content in the erythrocyte membrane as well as in red cell velocity in mesenteric venules. Our findings suggest that myakuryu treatment can improve blood flow and reduce adherent leukocytes in the venules of rats fed with HFD by ameliorating blood viscosity, erythrocyte deformability and aggregation, and other hemorheological characteristics.


Assuntos
Hemorreologia/efeitos dos fármacos , Hiperlipidemias/sangue , Fitoterapia/métodos , Preparações de Plantas/farmacologia , Actinas/sangue , Animais , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Viscosidade Sanguínea/efeitos dos fármacos , Peso Corporal , Adesão Celular/efeitos dos fármacos , Gorduras na Dieta/administração & dosagem , Avaliação Pré-Clínica de Medicamentos/métodos , Agregação Eritrocítica/efeitos dos fármacos , Membrana Eritrocítica/metabolismo , Hiperlipidemias/tratamento farmacológico , Hiperlipidemias/fisiopatologia , Leucócitos/efeitos dos fármacos , Lipídeos/sangue , Fluidez de Membrana/efeitos dos fármacos , Veias Mesentéricas/efeitos dos fármacos , Veias Mesentéricas/fisiopatologia , Microcirculação/efeitos dos fármacos , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Preparações de Plantas/uso terapêutico , Ratos , Ratos Wistar
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