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1.
J Hazard Mater ; 445: 130479, 2023 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-36455330

RESUMO

In recent years, metal-free catalysts for persulfate-mediated oxidation processes have been widely applied to remove contaminants in the aquatic environment. Herein, a simple pyrolysis approach was used to synthesize the boron doped biochars (B@TBCs) derived from boric acid mixed with tea seed shells powders. The obtained B@TBCs exhibited fantastic capability to boost PMS (0.5 mM) activation for 90%∼ removal of oxytetracycline (OTC) within 20 min. Through the correlation analysis and DFT calculations, it was concluded that the apparent rate constant of pollutants removal was greatly related to the -O-B-O- groups on the biochars, which could improve the electron-donating capacity of the biochar. In addition, the degradation process of OTC was pH-dependent because of the changed roles of ROSs under different pH. Finally, according to the DFT calculation, LC-MS and toxicological analysis, the degradation pathways of pollutants and the toxicity changes during the degradation process were obtained. These findings consolidated the theoretical basis for further boosting the catalytic activity of B-doped biochars and expanded the imagination for the modification of other metal-free biochar catalysts for PMS activation.


Assuntos
Poluentes Ambientais , Oxitetraciclina , Boro , Carvão Vegetal , Metais , Peróxidos
2.
Nat Commun ; 13(1): 4390, 2022 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-35906240

RESUMO

Lipid remodeling is crucial for malignant cell transformation and tumorigenesis, but the precise molecular processes involved and direct evidences for these in vivo remain elusive. Here, we report that oxysterol-binding protein (OSBP)-related protein 4 L (ORP4L) is expressed in adult T-cell leukemia (ATL) cells but not normal T-cells. In ORP4L knock-in T-cells, ORP4L dimerizes with OSBP to control the shuttling of OSBP between the Golgi apparatus and the plasma membrane (PM) as an exchanger of phosphatidylinositol 4-phosphate [PI(4)P]/cholesterol. The PI(4)P arriving at the PM via this transport machinery replenishes phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2] and phosphatidylinositol (3,4,5) trisphosphate [PI(3,4,5)P3] biosynthesis, thus contributing to PI3K/AKT hyperactivation and T-cell deterioration in vitro and in vivo. Disruption of ORP4L and OSBP dimerization disables PI(4)P transport and T-cell leukemogenesis. In summary, we identify a non-vesicular lipid transport machinery between Golgi and PM maintaining the oncogenic signaling competence initiating T-cell deterioration and leukemogenesis.


Assuntos
Fosfatidilinositol 3-Quinases , Receptores de Esteroides , Carcinogênese , Humanos , Fosfatidilinositol 4,5-Difosfato , Fosfatos de Fosfatidilinositol/metabolismo , Fosfatidilinositóis , Receptores de Esteroides/metabolismo , Linfócitos T/metabolismo
3.
Sci Transl Med ; 14(629): eabh2548, 2022 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-35080912

RESUMO

Leukemia stem cells (LSCs) propagate leukemia and are responsible for the high frequency of relapse of treated patients. The ability to target LSCs remains elusive, indicating a need to understand the underlying mechanism of LSC formation. Here, we report that miR-31-5p is reduced or undetectable in human LSCs compared to hematopoietic stem progenitor cells (HSPCs). Inhibition of miR-31-5p in HSPCs promotes the expression of its target gene FIH, encoding FIH [factor inhibiting hypoxia-inducing factor 1α (HIF-1α)], to suppress HIF-1α signaling. Increased FIH resulted in a switch from glycolysis to oxidative phosphorylation (OXPHOS) as the predominant mode of energy metabolism and increased the abundance of the oncometabolite fumarate. Increased fumarate promoted the conversion of HSPCs to LSCs and initiated myeloid leukemia-like disease in NOD-Prkdcscid IL2rgtm1/Bcgen (B-NDG) mice. We further demonstrated that miR-31-5p inhibited long- and short-term hematopoietic stem cells with a high frequency of LSCs. In combination with the chemotherapeutic agent Ara-C (cytosine arabinoside), restoration of miR-31-5p using G7 poly (amidoamine) nanosized dendriplex encapsulating miR-31-5p eliminated LSCs and inhibited acute myeloid leukemia (AML) progression in patient-derived xenograft mouse models. These results demonstrated a mechanism of HSC malignant transformation through altered energy metabolism and provided a potential therapeutic strategy to treat patients with AML.


Assuntos
Leucemia Mieloide Aguda , MicroRNAs , Animais , Fumaratos , Células-Tronco Hematopoéticas/metabolismo , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Camundongos , Camundongos Endogâmicos NOD , MicroRNAs/genética , MicroRNAs/metabolismo , Células-Tronco Neoplásicas/patologia
4.
Bioresour Technol ; 345: 126523, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34896530

RESUMO

Immobilized microorganism technology has attracted increasing attention for high concentration of microbes, low cell loss and high resistance to impact of environment. The microbial reduction of nitrate in the presence of sediment-based biochar (SBC) and nanoscale zero-valent iron (nZVI) was investigated in four different free systems. NZVI-SBC/bacteria system realized the best nitrate removal of 97.61% within 3 days through the synergistic effect of SBC and nZVI on denitrifying bacteria. Accumulation of nitrite and ammonium in nZVI-SBC/bacteria system also decreased. High-throughput sequencing results showed that the proportion of denitrifying bacteria in microbial community structure increased after adding nZVI-SBC. The performance of nitrate removal was then studied through PVA/SA-immobilization. Immobilized active pellets performed better nitrate removal (98.89%) and stronger tolerance under different conditions than the free bacterial cells. Overall, this study provided a promising approach by utilizing SBC and nZVI for the bio-remediation of nitrate-contaminated water in practical application.


Assuntos
Nitratos , Poluentes Químicos da Água , Carvão Vegetal , Ferro , Óxidos de Nitrogênio , Poluentes Químicos da Água/análise
5.
Blood ; 139(7): 1052-1065, 2022 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-34797912

RESUMO

Human T-cell leukemia virus 1 (HTLV-1) causes adult T-cell leukemia (ATL), but the mechanism underlying its initiation remains elusive. In this study, ORP4L was expressed in ATL cells but not in normal T-cells. ORP4L ablation completely blocked T-cell leukemogenesis induced by the HTLV-1 oncoprotein Tax in mice, whereas engineering ORP4L expression in T-cells resulted in T-cell leukemia in mice, suggesting the oncogenic properties and prerequisite of ORP4L promote the initiation of T-cell leukemogenesis. For molecular insight, we found that loss of miR-31 caused by HTLV-1 induced ORP4L expression in T-cells. ORP4L interacts with PI3Kδ to promote PI(3,4,5)P3 generation, contributing to AKT hyperactivation; NF-κB-dependent, p53 inactivation-induced pro-oncogene expression; and T-cell leukemogenesis. Consistently, ORP4L ablation eliminates human ATL cells in patient-derived xenograft ATL models. These results reveal a plausible mechanism of T-cell deterioration by HTLV-1 that can be therapeutically targeted.


Assuntos
Carcinogênese/patologia , Regulação Leucêmica da Expressão Gênica , Infecções por HTLV-I/complicações , Vírus Linfotrópico T Tipo 1 Humano/isolamento & purificação , Leucemia-Linfoma de Células T do Adulto/patologia , Receptores de Esteroides/metabolismo , Linfócitos T/imunologia , Animais , Apoptose , Carcinogênese/imunologia , Carcinogênese/metabolismo , Proliferação de Células , Produtos do Gene tax , Infecções por HTLV-I/virologia , Humanos , Leucemia-Linfoma de Células T do Adulto/genética , Leucemia-Linfoma de Células T do Adulto/metabolismo , Leucemia-Linfoma de Células T do Adulto/virologia , Camundongos , Prognóstico , Receptores de Esteroides/genética , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
6.
FASEB J ; 34(11): 14671-14694, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32914503

RESUMO

Oxysterol-binding protein-related protein 2 (ORP2), a cholesterol-PI(4,5)P2 countercurrent transporter, was recently identified as a novel regulator of plasma membrane (PM) cholesterol and PI(4,5)P2 content in HeLa cells. Here, we investigate the role of ORP2 in endothelial cell (EC) cholesterol and PI(4,5)P2 distribution, angiogenic signaling, and angiogenesis. We show that ORP2 knock-down modifies the distribution of cholesterol accessible to a D4H probe, between late endosomes and the PM. Depletion of ORP2 from ECs inhibits their angiogenic tube formation capacity, alters the gene expression of angiogenic signaling pathways such as VEGFR2, Akt, mTOR, eNOS, and Notch, and reduces EC migration, proliferation, and cell viability. We show that ORP2 regulates the integrity of VEGFR2 at the PM in a cholesterol-dependent manner, the depletion of ORP2 resulting in proteolytic cleavage by matrix metalloproteinases, and reduced activity of VEGFR2 and its downstream signaling. We demonstrate that ORP2 depletion increases the PM PI(4,5)P2 coincident with altered F-actin morphology, and reduces both VEGFR2 and cholesterol in buoyant raft membranes. Moreover, ORP2 knock-down suppresses the expression of the lipid raft-associated proteins VE-cadherin and caveolin-1. Analysis of the retinal microvasculature in ORP2 knock-out mice generated during this study demonstrates the subtle alterations of morphology characterized by reduced vessel length and increased density of tip cells and perpendicular sprouts. Gene expression changes in the retina suggest disturbance of sterol homeostasis, downregulation of VE-cadherin, and a putative disturbance of Notch signaling. Our data identifies ORP2 as a novel regulator of EC cholesterol and PI(4,5)P2 homeostasis and cholesterol-dependent angiogenic signaling.


Assuntos
Células Endoteliais da Veia Umbilical Humana/metabolismo , Neovascularização Fisiológica , Receptores de Esteroides/metabolismo , Transdução de Sinais , Actinas/metabolismo , Antígenos CD/metabolismo , Caderinas/metabolismo , Caveolinas/metabolismo , Membrana Celular/metabolismo , Movimento Celular , Endossomos/metabolismo , Células Endoteliais da Veia Umbilical Humana/fisiologia , Humanos , Metaloproteinases da Matriz/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Fosfatidilinositol 4,5-Difosfato/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores Notch/metabolismo , Receptores de Esteroides/genética , Receptores de Fatores de Crescimento do Endotélio Vascular/metabolismo , Serina-Treonina Quinases TOR/metabolismo
7.
Zhongguo Gu Shang ; 33(5): 440-4, 2020 May 25.
Artigo em Chinês | MEDLINE | ID: mdl-32452182

RESUMO

OBJECTIVE: To assess the curative effects of injured vertebra pedicle fixation combined with vertebroplasty and short-segment pedicle screw fixation combined with vertebroplasty in treatment of osteoporotic thoracolumbar burst fractures. METHODS: Seventy patients with osteoporotic thoracolumbar burst fractures who met the inclusion criteria were collected in the study from January 2015 to December 2017. Among them, 35 patients were treated with injured vertebra pedicle fixation combined with vertebroplasty (group A), including 20 males and 15 females, aged from 55 to 74 years with an average of (64.03± 7.82) years. Twenty-six cases were type A3 and 9 cases were type A4 according to the AO typing;another 35 patients were treated with short segment pedicle screw fixation combined with vertebroplasty (group B), including 18 males and 17 females, aged from 54 to 72 years with an average of (62.78±6.40) years. Twenty-eight cases were type A3 and 7 cases were type A4 according to AO typing. Operation length, intraoperative bleeding volume, complication, imaging parameters and clinical effects were compared between the two groups. RESULTS: All the patients were followed up for at least 12 months. There were no significant differences in gender, age, injury site, preoperative VAS, Cobb angle, and injured vertebral height before surgery. There were no significant differences in operation length, intraoperative bleeding volume between two groups. In terms of VAS scores before surgery, 1 week after surgery, and at the final follow up, group A was 5.5 ±2.5, 1.8 ±0.8, 0.9 ±0.4, group B was 5.4 ± 2.3, 1.7±0.6, 1.2±1.8, respectively;injured vertebral height was (40.4±8.8)%, (92.0±4.9)%, (87.1±3.8)% in group A, and (41.2±6.6)%, (93.2±4.6)%, (80.0±4.3)% in group B;Cobb angle was (18.4±6.9) °, (2.8±2.2) °, (4.2±2.6) ° in group A, and (16.8±7.2) °, (2.7±2.5) °, (6.0±2.4) ° in group B. There were significant differences in the 3 parameters above before the operation and at the final follow up in all groups (P<0.05). There were significant differences in the Cobb angle and injured vertebral height between 1 week after operation and at the final follow up (P<0.05). At the final follow up, injured vertebral height in group A was obviously better than that in group B (P<0.05). Internal fixation failure occurred in 2 cases from the group A, and occurred in 4 cases from the group B. There were no neurological complications in both groups. CONCLUSION: For osteoporotic thoracolumbar vertebral burst fractures, injured vertebra pedicle fixation combined with vertebroplasty and vertebra pedicle screw fixation combined with vertebroplasty can achieve good clinical effects. However, injured vertebra pedicle fixation combined with vertebroplasty is better at maintaining postoperative vertebral height and sagittal arrangement, and reducing internal fixation related complications. The treatment strategy is worthy of application and promotion.


Assuntos
Parafusos Pediculares , Fraturas da Coluna Vertebral , Vertebroplastia , Idoso , Feminino , Fixação Interna de Fraturas , Humanos , Vértebras Lombares , Masculino , Pessoa de Meia-Idade , Vértebras Torácicas , Resultado do Tratamento
8.
FASEB J ; 33(12): 13852-13865, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31648575

RESUMO

Oxysterol-binding protein-related protein (ORP) 4L acts as a scaffold protein assembling CD3-ε, G-αq/11, and PLC-ß3 into a complex at the plasma membrane that mediates inositol (1,4,5)-trisphosphate (IP3)-induced endoplasmic reticulum (ER) Ca2+ release and oxidative phosphorylation in T-cell acute lymphoblastic leukemia cells. Here, we offer new evidence that ORP4L interacts with the carboxyl terminus of the IP3 receptor type 1 (ITPR1) in Jurkat T cells. ORP4L enables IP3 binding to ITPR1; a truncated construct that lacks the ITPR1-binding region retains the ability to increase IP3 production but fails to mediate IP3 and ITPR1 binding. In association with this ability of ORP4L, it enhances Ca2+ release from the ER and subsequent cytosolic and mitochondrial parallel Ca2+ spike oscillations that stimulate mitochondrial energetics and thus maintains cell survival. These data support a novel model in which ORP4L is a cofactor of ITPR1, which increases ITPR1 sensitivity to IP3 and enables ER Ca2+ release.-Cao, X., Chen, J., Li, D., Xie, P., Xu, M., Lin, W., Li, S., Pan, G., Tang, Y., Xu, J., Olkkonen, V. M., Yan, D., Zhong, W. ORP4L couples IP3 to ITPR1 in control of endoplasmic reticulum calcium release.


Assuntos
Cálcio/metabolismo , Retículo Endoplasmático/metabolismo , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Receptores de Esteroides/metabolismo , Linhagem Celular Tumoral , Membrana Celular/metabolismo , Sobrevivência Celular/fisiologia , Citosol/metabolismo , Humanos , Inositol 1,4,5-Trifosfato/metabolismo , Células Jurkat , Mitocôndrias/metabolismo , Fosforilação Oxidativa , Fosfolipase C beta/metabolismo
9.
Cell Rep ; 26(8): 2166-2177.e9, 2019 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-30784597

RESUMO

Leukemia stem cells (LSCs) are a rare subpopulation of abnormal hematopoietic stem cells (HSCs) that propagates leukemia and are responsible for the high frequency of relapse in therapies. Detailed insights into LSCs' survival will facilitate the identification of targets for therapeutic approaches. Here, we develop an inhibitor, LYZ-81, which targets ORP4L with high affinity and specificity and selectively eradicates LCSs in vitro and in vivo. ORP4L is expressed in LSCs but not in normal HSCs and is essential for LSC bioenergetics and survival. It extracts PIP2 from the plasma membrane and presents it to PLCß3, enabling IP3 generation and subsequent Ca2+-dependent bioenergetics. LYZ-81 binds ORP4L competitively with PIP2 and blocks PIP2 hydrolysis, resulting in defective Ca2+ signaling. The results provide evidence that LSCs can be eradicated through the inhibition of ORP4L by LYZ-81, which may serve as a starting point of drug development for the elimination of LSCs to eventually cure leukemia.


Assuntos
Células-Tronco Hematopoéticas/efeitos dos fármacos , Leucemia/metabolismo , Células-Tronco Neoplásicas/efeitos dos fármacos , Fosfatidilinositol 4,5-Difosfato/metabolismo , Receptores de Esteroides/metabolismo , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Membrana Celular/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Humanos , Leucemia/sangue , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Células-Tronco Neoplásicas/metabolismo , Fosfolipase C beta/metabolismo , Receptores de Esteroides/antagonistas & inibidores
10.
FASEB J ; 33(1): 545-556, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30004795

RESUMO

The enhanced expression of miR-31 has been observed in many human malignancies including lung cancer, and this microRNA regulates several aspects of oncogenesis. However, the role of miR-31-5p in energy metabolism remains elusive. Here, we confirm that H1299 and A549 cells, 2 lung cancer cell lines, relay on aerobic glycolysis as main source of ATP. Inhibition of miR-31-5p leads to decreased glycolysis and ATP production, while miR-31-5p overexpression increases them. Hypoxia inducible factor 1 (HIF-1) up-regulates the expression of glycolytic enzymes, and the HIF-1α inhibitor (FIH) inhibits HIF-1 activity. Because FIH is a direct target of miR-31-5p, inhibition of miR-31-5p results in enhanced FIH expression and suppression of HIF-1 signaling, while overexpression of miR-31-5p has the opposite effects. Via this mechanism, miR-31-5p up-regulates aerobic glycolytic genes and maintains energy homeostasis. To further validate the mechanism of miR-31-5p in glycolysis regulation, we show that overexpression or knockdown of FIH rescued the effects of miR-31-5p or miR-31-5p inhibitor on HIF activation and its target gene expression, respectively. Finally, by means of an A549 cell xenograft mouse model, we demonstrate that the miR-31-5p promotes cell proliferation via enhancing glycolysis. In summary, this study reveals that miR-31-5p promotes the Warburg effect via direct targeting of FIH.-Zhu, B., Cao, X., Zhang, W., Pan, G., Yi, Q., Zhong, W., Yan, D. MicroRNA-31-5p enhances the Warburg effect via targeting FIH.


Assuntos
Glicólise , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Ácido Láctico/metabolismo , Neoplasias Pulmonares/patologia , MicroRNAs/genética , Oxigenases de Função Mista/metabolismo , Ácido Pirúvico/metabolismo , Proteínas Repressoras/metabolismo , Animais , Apoptose , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Oxigenases de Função Mista/genética , Proteínas Repressoras/genética , Transdução de Sinais , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
11.
J Biol Chem ; 293(45): 17430-17441, 2018 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-30237164

RESUMO

Phosphoinositide phospholipases C (PLCs) are a family of eukaryotic intracellular enzymes with important roles in signal transduction. In addition to their location at the plasma membrane, PLCs also exist within the cell nucleus where they are stored. We previously demonstrated that OSBP-related protein 4L (ORP4L) anchors cluster of differentiation 3ϵ (CD3ϵ) to the heterotrimeric G protein subunit (Gαq/11) to control PLCß3 relocation and activation. However, the underlying mechanism by which ORP4L facilitates PLCß3 translocation remains unknown. Here, using confocal immunofluorescence microscopy and coimmunoprecipitation assays, we report that ORP4L stimulates PLCß3 translocation from the nucleus to the plasma membrane in Jurkat T-cells in two steps. First, we found that ORP4L is required for the activation of Ras-related nuclear protein (RAN), a GTP-binding nuclear protein that binds to exportin 1 and eventually promotes the nuclear export of PLCß3. Second, we also observed that ORP4L interacts with vesicle-associated membrane protein-associated protein A (VAPA) through its two phenylalanines in an acidic tract (FFAT) motif. This complex enabled PLCß3 movement to the plasma membrane, indicating that PLCß3 translocation occurs in a VAPA-dependent manner. This study reveals detailed mechanistic insight into the role of ORP4L in PLCß3 redistribution from storage within the nucleus to the plasma membrane via RAN activation and interaction with VAPA in Jurkat T-cells.


Assuntos
Membrana Celular/metabolismo , Núcleo Celular/metabolismo , Fosfolipase C beta/metabolismo , Receptores de Esteroides/metabolismo , Linfócitos T/metabolismo , Transporte Ativo do Núcleo Celular/fisiologia , Membrana Celular/genética , Núcleo Celular/genética , Subunidades alfa de Proteínas de Ligação ao GTP/genética , Subunidades alfa de Proteínas de Ligação ao GTP/metabolismo , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/genética , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/metabolismo , Células HeLa , Células Hep G2 , Humanos , Células Jurkat , Células K562 , Fosfolipase C beta/genética , Receptores de Esteroides/genética , Linfócitos T/citologia , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/metabolismo , Proteína ran de Ligação ao GTP/genética , Proteína ran de Ligação ao GTP/metabolismo
12.
Cell Calcium ; 72: 62-69, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29748134

RESUMO

Oxysterol-binding protein related-protein 5 and 8 (ORP5/8) localize to the membrane contact sites (MCS) of the endoplasmic reticulum (ER) and the mitochondria, as well as to the ER-plasma membrane (PM) MCS. The MCS are emerging as important regulators of cell signaling events, including calcium (Ca2+) signaling. ORP5/8 have been shown to interact with phosphatidylinositol-4,5-bisphosphate (PIP2) in the PM, and to modulate mitochondrial respiration and morphology. PIP2 is the direct precursor of inositol trisphosphate (IP3), a key second messenger responsible for Ca2+-release from the intracellular Ca2+ stores. Further, mitochondrial respiration is linked to Ca2+ transfer from the ER to the mitochondria. Hence, we asked whether ORP5/8 would affect Ca2+ signaling in these cell compartments, and employed genetically engineered aequorin Ca2+ probes to investigate the effect of ORP5/8 in the regulation of mitochondrial and caveolar Ca2+. Our results show that ORP5/8 overexpression leads to increased mitochondrial matrix Ca2+ as well as to increased Ca2+ concentration at the caveolar subdomains of the PM during histamine stimulation, while having no effect on the cytoplasmic Ca2+. Also, we found that ORP5/8 overexpression increases cell proliferation. Our results show that ORP5/8 regulate Ca2+ signaling at specific MCS foci. These local ORP5/8-mediated Ca2+ signaling events are likely to play roles in processes such as mitochondrial respiration and cell proliferation.


Assuntos
Sinalização do Cálcio , Compartimento Celular , Receptores de Esteroides/metabolismo , Sinalização do Cálcio/efeitos dos fármacos , Compartimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Citosol/efeitos dos fármacos , Citosol/metabolismo , Regulação para Baixo/efeitos dos fármacos , Células HeLa , Histamina/farmacologia , Humanos , Inositol 1,4,5-Trifosfato/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo
13.
Sci Rep ; 7(1): 6132, 2017 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-28733653

RESUMO

Tungsten-doped VO2 thin films have been synthesized by a modified sol-gel process and followed by a post annealing. Vanadium pentoxide and tungstic acid as raw materials with the addition of hydrogen peroxide, concentrated hydrochloric acid (catalyst) and oxalic acid used as reducing agent were reacted in isobutanol. Finally, the uniform sol of vanadyl oxalate in isobutanol solvent was obtained as precursor. Detailed study suggested that W doped in VO2 introduces additional electron carriers and induces the formation of V3+. Post annealing under vacuum promotes the releasing of chemical stress and generates oxygen vacancies in the samples. Temperature dependent transmittance study revealed that the releasing of chemical stress and deliberately introducing oxygen vacancies in W-doped VO2 films have positive effects on enhancing its switching ability in the infrared transmittance as the metal-insulator transition (MIT) occurs. The largest switching of transmittance was obtained about 48% in the infrared range at 43 °C in 1.5%W doped VO2 films, which is significantly larger than the reported ones. The findings in this work open a new way to synthesize the novel and thermochromic W doped VO2 films with facility and low cost. Therefore, it has extensive application to construct smart windows and electronic devices.

14.
Circ Res ; 119(12): 1296-1312, 2016 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-27729467

RESUMO

RATIONALE: Macrophage survival within the arterial wall is a central factor contributing to atherogenesis. Oxysterols, major components of oxidized low-density lipoprotein, exert cytotoxic effects on macrophages. OBJECTIVE: To determine whether oxysterol-binding protein-related protein 4 L (ORP4L), an oxysterol-binding protein, affects macrophage survival and the pathogenesis of atherosclerosis. METHODS AND RESULTS: By hiring cell biological approaches and ORP4L-/- mice, we show that ORP4L coexpresses with and forms a complex with Gαq/11 and phospholipase C (PLC)-ß3 in macrophages. ORP4L facilitates G-protein-coupled ligand-induced PLCß3 activation, IP3 production, and Ca2+ release from the endoplasmic reticulum. Through this mechanism, ORP4L sustains antiapoptotic Bcl-XL expression through Ca2+-mediated c-AMP responsive element binding protein transcriptional regulation and thus protects macrophages from apoptosis. Excessive stimulation with the oxysterol 25-hydroxycholesterol disassembles the ORP4L/Gαq/11/PLCß3 complexes, resulting in reduced PLCß3 activity, IP3 production, and Ca2+ release, as well as decreased Bcl-XL expression and increased apoptosis. Overexpression of ORP4L counteracts these oxysterol-induced defects. Mice lacking ORP4L exhibit increased apoptosis of macrophages in atherosclerotic lesions and a reduced lesion size. CONCLUSIONS: ORP4L is crucial for macrophage survival. It counteracts the cytotoxicity of oxysterols/oxidized low-density lipoprotein to protect macrophage from apoptosis, thus playing an important role in the development of atherosclerosis.


Assuntos
Aterosclerose/metabolismo , Aterosclerose/prevenção & controle , Macrófagos/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Esteroides/metabolismo , Transdução de Sinais/fisiologia , Animais , Aterosclerose/patologia , Sobrevivência Celular/fisiologia , Células Cultivadas , Humanos , Macrófagos/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
15.
J Nanosci Nanotechnol ; 13(8): 5580-5, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23882798

RESUMO

Highly ordered TiO2 nano-tube arrays (TNTAs) photoelectrodes were prepared through anodization method, followed by annealing treatment. Morphologies and structures of the as-prepared TNTAs samples were investigated through scanning electron microscopy (SEM) and X-ray diffraction (XRD). In addition, the optical and photoelectrochemical (PECH) properties were investigated through ultraviolet-visible diffuse reflectance spectroscopy (UV-vis DRS) and transient photocurrent response. Furthermore, the photodecomposition performances were investigated through the yield of hydroxyl (*OH) radicals and photocatalytic (PC) degradation of RhB under Xenon light irradiation. Results indicated that the TNTAs samples annealed at 723 K exhibited the highest photocurrent response, PC performance and yield of *OH radicals, in which 60.8% of RhB could be degraded by PC degradation within 60 min. The high PC performance could mainly be attributed to the anatase structure, high crystallinity and highly ordered nano-tubular structure, which favored the transfer and separation of photoinduced charge carriers. This study suggests that highly ordered nano-structure could provide superior pathway for the charge transfer and separation.

16.
Zhongguo Gu Shang ; 25(11): 953-6, 2012 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-23427601

RESUMO

OBJECTIVE: To analyze the manifestation and investigate the value of MRI in the diagnosis of giant cell tumor of tendon sheath (GCTTS). METHODS: Twenty patients with GCTTS proved by operation and pathology were retrospectively analyzed. There were 8 males and 12 females. The average age was 35.5 years, range from 15 to 61 years. All the patients underwent MRI examination. RESULTS: Among the 20 cases, 16 patients had the tumor in knee joint, 2 patients had the tumor in interphalangeal articulation of foot and ankle joint respectively. Nineteen patients had limited tumor and 1 patient had diffuse tumor. The soft tissue mass localized beside lower extremity osteoarticulation was displayed on MRI images. On T1WI, the signal intensities of GCTTS almost equaled to those of skeletal muscle in 15 cases and were slightly lower than those of skeletal muscle in 5 cases. On T2WI, the signal intensities tended to range between those of skeletal muscle and fat in 4 cases, almost equaled to those of skeletal muscle in 13 cases, and were slightly lower than those of skeletal muscle in 3 cases. In the 16 patients with gadolinium-enhanced images on T1WI, 5 patients showed homogeneous enhancement and 11 patients showed inhomogeneous enhancement. Four patients had adjacent bone destruction. CONCLUSION: The location, shape and inner signal characteristic of GCTTS localized beside lower extremity osteoarticulation could be demonstrated clearly by MRI examination, which is valuable for clinical diagnosis, guiding treatment and follow-up visit.


Assuntos
Tumores de Células Gigantes/patologia , Imageamento por Ressonância Magnética/métodos , Tendões/patologia , Adolescente , Adulto , Feminino , Humanos , Extremidade Inferior , Masculino , Pessoa de Meia-Idade
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