Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 61
Filtrar
1.
J Biol Chem ; 299(6): 104812, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37172724

RESUMO

T-cell acute lymphoblastic leukemia (T-ALL) is one of the deadliest and most aggressive hematological malignancies, but its pathological mechanism in controlling cell survival is not fully understood. Oculocerebrorenal syndrome of Lowe is a rare X-linked recessive disorder characterized by cataracts, intellectual disability, and proteinuria. This disease has been shown to be caused by mutation of oculocerebrorenal syndrome of Lowe 1 (OCRL1; OCRL), encoding a phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2] 5-phosphatase involved in regulating membrane trafficking; however, its function in cancer cells is unclear. Here, we uncovered that OCRL1 is overexpressed in T-ALL cells, and knockdown of OCRL1 results in cell death, indicating the essential role of OCRL in controlling T-ALL cell survival. We show OCRL is primarily localized in the Golgi and can translocate to plasma membrane (PM) upon ligand stimulation. We found OCRL interacts with oxysterol-binding protein-related protein 4L, which facilitates OCRL translocation from the Golgi to the PM upon cluster of differentiation 3 stimulation. Thus, OCRL represses the activity of oxysterol-binding protein-related protein 4L to prevent excessive PI(4,5)P2 hydrolysis by phosphoinositide phospholipase C ß3 and uncontrolled Ca2+ release from the endoplasmic reticulum. We propose OCRL1 deletion leads to accumulation of PI(4,5)P2 in the PM, disrupting the normal Ca2+ oscillation pattern in the cytosol and leading to mitochondrial Ca2+ overloading, ultimately causing T-ALL cell mitochondrial dysfunction and cell death. These results highlight a critical role for OCRL in maintaining moderate PI(4,5)P2 availability in T-ALL cells. Our findings also raise the possibility of targeting OCRL1 to treat T-ALL disease.


Assuntos
Membrana Celular , Fosfatidilinositol 4,5-Difosfato , Monoéster Fosfórico Hidrolases , Leucemia-Linfoma Linfoblástico de Células T Precursoras , Linfócitos T , Humanos , Membrana Celular/metabolismo , Sobrevivência Celular , Hidrólise , Síndrome Oculocerebrorrenal/enzimologia , Síndrome Oculocerebrorrenal/genética , Fosfatidilinositol 4,5-Difosfato/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/imunologia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Linfócitos T/citologia , Linfócitos T/imunologia , Monoéster Fosfórico Hidrolases/biossíntese , Monoéster Fosfórico Hidrolases/deficiência , Monoéster Fosfórico Hidrolases/genética , Monoéster Fosfórico Hidrolases/metabolismo , Complexo de Golgi/metabolismo , Ligantes , Transporte Proteico , Sinalização do Cálcio , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Citosol/metabolismo
2.
Chemistry ; 30(12): e202303717, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38072903

RESUMO

Organic-inorganic hybrid multifunctional materials have shown significant application in lighting and sensor fields, owing to their prominent performance and diversity structures. Herein, we synthesized two multifunctional compounds: (propyl-quinuclidone)2 CdBr4 (1) and (F-butyl-quinuclidone)2 CdBr4 (2). By introducing light-emitting organic cation with flexible long chain, 1 and 2 exhibit excellent transition properties and bright blue-white fluorescence. Then, combine fluorescence lifetime and first-principal calculation, providing evidence for the electron transfer emission. Subsequently, investigated the impact of substituent carbon chain length (methyl to butyl), structural rigidity (C-C to C-F) and halide framework (Cl to I) on the fluorescence properties. Results indicate that Cd⋅⋅⋅Cd distance and structural rigidity play an important role in fluorescence. Overall, our research provides valuable insight and example for chemical modifications enhance compound performance.

3.
Inorg Chem ; 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39255341

RESUMO

Advances in materials science are increasingly dependent on the development of multifunctional materials capable of improving system efficiency and reducing the environmental impact. In this study, two zero-dimensional (0D) cadmium-based organic-inorganic hybrid materials (BEMPD)2CdBr4 (BEMPD-Br, 1) and (BEMPD)2CdBr2Cl2 (BEMPD-ClBr, 2) (BEMPD = 1-(2-bromoethyl)-1-methylpiperidine) were prepared by halogen doping. Compound 2 is a mixed halide in which there are two halogen sites, Cl and Br, and in a disordered state, which has a regulatory effect on the structural distortion and properties of the compound. The Curie temperatures of compounds 1 and 2 are 348 and 390 K, respectively, and the UV-vis absorption spectra showed that the direct band gaps of compounds 1 and 2 were 4.68 and 4.8 eV, respectively. In addition, room-temperature photoluminescence experiments show broadband emission peaks at 717 and 683 nm for compounds 1 and 2, respectively, with fluorescence lifetimes of 2.414 and 3.915 µs. These 0D hybrids provide an avenue for the development of smart materials and optoelectronic devices, and also provide positive clues for manipulating the properties of organic-inorganic hybrid compounds.

4.
Inorg Chem ; 63(6): 3083-3090, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38278552

RESUMO

Two-dimensional double perovskites have experienced rapid development due to their outstanding optoelectronic properties and diverse structural characteristics. However, the synthesis of high-performance multifunctional compounds and the regulation of their properties still lack relevant examples. Herein, we synthesized two multifunctional compounds, (C6H14N)4AgSbBr8 (1) and (F2-C6H12N)4AgSbBr8 (2), which exhibit high solid-state phase transition temperature, bistable dielectric constant switching, second harmonic generation (SHG), and bright emission. Through H/F substitution, the transition temperature increases and achieves a smaller band gap attributed to reduced interlayer spacing. Furthermore, we investigated the broad emission mechanism of the compounds through first-principles calculation and variable-temperature fluorescence, confirming the presence of the STE1 emission. Our work provides insight into the further development of multifunctional compounds and chemical modification that enhances compound properties.

5.
Inorg Chem ; 63(7): 3411-3417, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38311915

RESUMO

In the past decade, metal halide materials have been favored by many researchers because of their excellent physical and chemical properties under thermal, electrical, and light stimuli, such as ferroelectricity, dielectric, nonlinearity, fluorescence, and semiconductors, greatly promoting their application in optoelectronic devices. In this study, we successfully constructed an unleaded organic-inorganic hybrid perovskite crystal: [Cl-C6H4-(CH2)2NH3]3SbBr6 (1), which underwent a high-temperature reversible phase transition near Tp = 368 K. The phase transition behavior of 1 was characterized by differential scanning calorimetry, accompanied by a thermal hysteresis of 6 K. In addition, variable-temperature Raman spectroscopy analysis and PXRD further verified the sensitivity of 1 to temperature and the phase transition from low symmetry to high symmetry. Temperature-dependent dielectric testing shows that 1 can be a sensitive switching dielectric constant switching material. Remarkably, 1 exhibits strong photoluminescence emission with a wavelength of 478 nm and a narrow band gap of 2.7 eV in semiconductors. As the temperature increases and decreases, fluorescence undergoes significant changes, especially near Tc, which further confirms the reversible phase transition of 1. All of these findings provide new avenues for designing and assembling new phase change materials with high Tp and photoluminescence properties.

6.
Chemistry ; 29(17): e202203893, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36579748

RESUMO

One dimensional (1D) organic-inorganic halide hybrid perovskites have the advantages of excellent organic cation modifiability and diversity of inorganic framework structures, which cannot be ignored in the development of multi-functional phase-transition materials in photoelectric and photovoltaic devices. Here, we have successfully modified and synthesized an organic-inorganic hybrid perovskite photoelectric multifunctional phase-transition material: [C7 H13 ONCH2 F]⋅PbBr3 (1). The synergistic effect of the order double disorder transition of organic cations and the change of the degree of distortion of the inorganic framework leads to its high temperature reversible phase-transition point of Tc =374 K/346 K and its ultra-low loss high-quality dielectric switch response. Through in-depth research and calculation, compound 1 also has excellent semiconductor characteristics with a band gap of 3.06 eV and the photoluminescence characteristics of self-trapped exciton (STE) broadband emission. Undoubtedly, this modification strategy provides a new choice for the research field of organic-inorganic hybrid perovskite reversible phase-transition photoelectric multifunctional materials with rich coupling properties.

7.
Chemistry ; 29(57): e202301499, 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37493075

RESUMO

The combination of chirality and phase-transition materials has broad application prospects. Therefore, based on the quasi-spherical theory and the thought strategy of introducing chirality, we have successfully synthesized a pair of chiral enantiomeric ligands (R/S)-triethyl-(2-hydroxypropyl)ammonium iodide, which can be combined with a tin hexachloride anion to obtain a pair of new organic-inorganic hybrid enantiomeric high-temperature plastic phase-transition materials: (R/S)-[CH3 CH(OH)CH2 N(CH2 CH3 )3 ]2 SnCl6 (1-R/1-S), which have a high temperature phase transition of Tc =384 K, crystallize in the P21 chiral space group at room temperature, and have obvious CD signals. In addition, compounds 1-R and 1-S have a good low-loss dielectric switch and broadband gap. This work is conducive to the research into chiral high-temperature reversible plastic phase-transition materials, and promotes the development of multi-functional phase-transition materials.

8.
Inorg Chem ; 62(31): 12525-12533, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37494604

RESUMO

Switchable materials have gained significant attention due to their potential applications in data storage, sensors, and switching devices. Two-dimensional (2D) hybrid perovskites have demonstrated promising prospects for designing switchable materials, where the dynamic motion of the organic components coupled with the distortion of the inorganic framework provides the driving force for triggering multifunctional switchable properties. Herein, through the H/F substitution strategy, we report a polar 2D hybrid lead-based perovskite, (4,4-DCA)2PbBr4 (4,4-DCA = 4,4-difluorocyclohexylammonium) (1), which exhibits dual-stable behavior in a dielectric and second harmonic generation (SHG) response during the reversible phase transition process near the high Curie temperature Tc ∼ 409 K. The phase transition temperature is significantly increased by 41 K compared to the corresponding non-fluorinated (CHA)2PbBr4 (CHA = cyclohexylammonium). Remarkably, the material shows rare broad-band yellow emission under UV excitation, attributed to the induction of self-trapped exciton emission by the distortion of the [PbBr6]4- octahedra, as confirmed by the first-principles analysis. 1 also exhibited ferroelectricity with a saturation polarization value and a small coercive field. This study provides a new insight into the modification of multifunctional switchable materials through the H/F substitution strategy.

9.
Inorg Chem ; 62(27): 10847-10853, 2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37366025

RESUMO

Hybrid organic-inorganic perovskites (HOIPs) have attracted much attention due to their excellent properties and easy synthesis. As far as we know, most documented ferroelastics mainly focus on the 3D (three-dimensional) perovskites, the 2D monolayer perovskite ferroelastics are rarely reported before. In this work, we synthesized a 2D lead-based perovskite (C5NH13Br)2PbBr4 (1) (C5NH13Br = 5-bromoamylamine cation) by introducing flexible chain organic cations. The evolution of ferroelastic domains observed by a polarized light microscope confirms that compound 1 undergoes a ferroelastic phase transition at 392/384 K. In addition, its direct band gap is 2.877 eV. Interestingly, the material emits an attractive blue light (quantum yield 5.06%) under UV light. Three structural descriptors are introduced to quantitatively analyze the relationship between structural distortion and the shape of emission peak. This work provides a way to design multifunctional perovskite-type materials.

10.
Inorg Chem ; 62(15): 6189-6195, 2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-37014228

RESUMO

Since the switchable spontaneous polarization of ferroelectric materials endows it with many useful properties such as a large pyroelectric coefficient, switchable spontaneous polarization, and semiconductor, it has a wide range of application prospects, and the research of high-performance molecular ferroelectric materials has become a hot spot. We obtained a 0D organic-inorganic hybrid ferroelectric [(CH3)3NCH2CH2CH3]2FeCl4 (1) with well-defined ferroelectric domains and excellent domain inversion and exhibited a relatively large spontaneous polarization (Ps = 9 µC/m-2) and a Curie temperature (Tc) of 394 K. Furthermore, compound 1 belongs to the non-centrosymmetrical space group Cmc21 and has a strong second-harmonic generation signal. Interestingly, we also performed magnetic tests on 1, which confirmed that it is a magnetic material. This work provides clues for exploring the application of high-performance molecular ferroelectric materials in future multifunctional smart devices.

11.
Cell Biol Toxicol ; 39(4): 1297-1317, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36070022

RESUMO

Autophagy is typically activated in cancer cells as a rescue strategy in response to cellular stress (e.g., chemotherapy). Herein, we found that Berbamine Hydrochloride (Ber) can act as an effective inhibitor of the late stage of autophagic flux, thereby potentiating the killing effect of chemotherapy agents. Lung carcinoma cells exposed to Ber exhibited increased autophagosomes, marked by LC3-II upregulation. The increased level of p62 after Ber treatment indicated that the autophagic flux was blocked at the late stage. The lysosome staining assay and cathepsin maturation detection indicated impaired lysosomal acidification. We found that Nox2 exhibited intensified co-localization with lysosomes in Ber-treated cells. Nox2 is a key enzyme for superoxide anion production capable of transferring electrons into the lysosomal lumen, thereby neutralizing the inner protons; this might explain the aberrant acidification. This hypothesis is further supported by the observed reversal of lysosomal cathepsin maturation by Nox2 inhibitors. Finally, Ber combined with cisplatin exhibited a synergistic killing effect on lung carcinoma cells. Further data suggested that lung carcinoma cells co-treated with Ber and cisplatin accumulated excessive reactive oxygen species (ROS), which typically activated MAPK-mediated mitochondria-dependent apoptosis. The enhanced anti-cancer effect of Ber combined with cisplatin was also confirmed in an in vivo xenograft mouse model. These findings indicate that Ber might be a promising adjuvant for enhancing the cancer cell killing effect of chemotherapy via the inhibition of autophagy. In this process, Nox2 might be a significant mediator of Ber-induced aberrant lysosomal acidification.


Assuntos
Antineoplásicos , Carcinoma , Neoplasias Pulmonares , Humanos , Animais , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Cisplatino/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Autofagia , Apoptose , Lisossomos/metabolismo , Pulmão/metabolismo , Concentração de Íons de Hidrogênio , Catepsinas/metabolismo , Catepsinas/farmacologia , Catepsinas/uso terapêutico , Carcinoma/tratamento farmacológico , Carcinoma/metabolismo
12.
Inorg Chem ; 61(50): 20608-20615, 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36459153

RESUMO

Plastic crystals, as a molecular material with multiple functions, have become a research hotspot in the exploration of new ferroelectric crystal compounds, especially due to their unique solid-solid phase transition properties. Based on this, we synthesized a new 0D organic-inorganic hybrid Fe-based plastic ferroelectric [(CH3)3NCH2CHCH2]FeCl4 (1), which has a high-temperature phase transition point of 393 K, obvious ferroelectric domains, and spontaneous polarization and has been tested by dielectric and piezoelectric power microscopy (PFM) and ultraviolet absorption (UV-vis). At room temperature, it crystallizes in the space group Cmc21 and has an obvious SHG switch. In addition, compound 1 also has an optical narrow band gap of 2.45 eV, indicating that compound 1 is a high-quality semiconductor material. This work advances the development of plastic ferroelectrics and provides an avenue for exploring the frequency-doubling response and optoelectronic properties of high-temperature plastic ferroelectrics.

13.
Inorg Chem ; 61(27): 10454-10460, 2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35762569

RESUMO

Multifunctional materials have always been an attractive research area, but how to combine multiple excellent properties in one compound remains a considerable challenge. Organic-inorganic hybrid compounds are widely used in the design of such materials due to their rich properties and flexible assembly. Herein, two new manganese(II)-based organic-inorganic hybrid compounds, (C6NH16)2MnBr4 (1) and (C7NH18)2MnBr4 (2), are prepared by the solution method. Compounds 1 and 2 both emit extremely strong green light under UV excitation, with high quantum yields of 45.93 and 50.98%, respectively. In addition, reversible solid-state phase transitions and obvious switchable dielectric properties are shown at 378/366 and 361/352 K, respectively. The coexistence of the dual stimulus-response characteristics of temperature and light in compounds 1 and 2 opens a new path for exploring more multifunctional phase transition materials.

14.
Chemistry ; 27(63): 15716-15721, 2021 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-34498317

RESUMO

The multifunctional two-dimensional (2D) organic-inorganic hybrid perovskites have potential applications in many fields, such as, semiconductor, energy storage and fluorescent device etc. Here, a 2D Ruddlesden-Popper (RP) perovskite (IPA)2 (FA)Pb2 I7 (1, IPA+ =C3 H9 NI+ , FA+ =CN2 H5 + ) is determined for its photophysical properties. Strikingly, 1 reveals a solid reversible phase transition with Tc of 382 K accompanied by giant entropy change of 40 J mol-1 K-1 . Further optical investigations indicate that 1 reveals a narrow direct bandgap (2.024 eV) attributed to the slight bending of I-Pb-I edge and inorganic [Pb2 I7 ]n layer and a superior photoluminescence (PL) emission with super long lifetime of 0.1607 ms. It is believed that this work will pave an avenue to further design multifunctional semiconductors that combines energy storage and photoelectric materials.

15.
Inorg Chem ; 60(24): 18918-18923, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34872246

RESUMO

A novel organic-inorganic hybrid perovskite crystal, [ClC6H4(CH2)2NH3]2CuBr4 (1), having experienced an invertible high-temperature phase transition near Tc (the Curie temperature Tc = 355 K), has been successfully synthesized. The phase-transition characteristics for compound 1 are thoroughly revealed by specific heat capacity (Cp), differential thermal analysis, and differential scanning calorimetry tests, possessing 16 K broad thermal hysteresis. Multiple-temperature powder X-ray diffraction analysis further proves the phase-transition behavior of compound 1. Moreover, compound 1 exhibits a significant steplike dielectric response near Tc, revealing that it can be deemed to be a promising dielectric switching material. The variable-temperature fluorescence experiments show distinct photoluminescence (PL) changes of compound 1. Further investigation and calculation disclose that the fluorescence lifetime of compound 1 can reach as long as 55.46 µs, indicating that it can be a potential PL material. All of these researches contribute a substitutable avenue in the design and construction of neoteric phase-transition compounds combining high Curie temperature and PL properties.

16.
Inorg Chem ; 60(2): 1195-1201, 2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33356190

RESUMO

Due to the existence of some cross properties such as SHG (second-harmonic generation), ferroelectricity, piezoelectricity, and thermoelectricity, molecular ferroelectrics have been widely used as a composite multipurpose material. Particularly, organic-inorganic molecular ferroelectrics have received much interest recently because of their unique flexible structures, friendly environment, ease of synthesis, etc. Also, these hybrids show great flexibility in band-gap engineering. Here we report a new molecular halide, [C6H13N3SbBr5]n (1; C6H13N3 = 1-(3-aminopropyl)imidazole), which experiences a unique ferroelectric to paraelectric phase transition at around 230 K from space group P21 to P21/c. Significantly, compound 1 exhibits a narrow band gap with a value of 2.52 eV, large pronounced SHG-active, perfect rectangle hysteresis loops with a large spontaneous polarization of 6.86 µC/cm2. DSC (differential scanning calorimetry) and dielectric dependence on temperature tests and the volume change before and after the phase transition show that compound 1 is characterized by a second-order phase transition. These findings will contribute to the multifunctional materials field of organic-inorganic hybrids.

17.
Chemistry ; 26(26): 5887-5892, 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32040218

RESUMO

Smart multifunctional molecular ferroelectrics bearing high Curie temperatures and diverse excellent physical properties, such as second harmonic generation (SHG) responses, luminescence, and semiconductivity, among others, have significant applications but have seldom been documented. Herein, the rare-earth metals Nd and Pr are introduced into a simple molecular system (nBu4 N)3 [M(NO3 )x (SCN)y ] (nBu4 N= tetrabutyl ammonium, M=rare-earth metal, nBu=CH3 CH2 CH2 CH2 ), and two new multifunctional molecular ferroelectrics are obtained: (nBu4 N)3 [Nd(NO3 )4 (SCN)2 ] (1) and (nBu4 N)3 [Pr(NO3 )4 (SCN)2 ] (2). Their distinct heat and dielectric anomaly dependence on temperature verifies that compounds 1 and 2 experience high-temperature para-ferroelectric phase transitions at 408 and 413 K, respectively. Strikingly, both molecular ferroelectrics possess large spontaneous polarization with Ps values of 9.05 and 8.50 µC cm-2 , respectively, and are further characterized by the appearance of multiple intersecting non-180° domains and polarization switching behavior. In particular, compounds 1 and 2 show good stability with only a small decrease in SHG intensity after switching cycles, suggesting that they have great potential for application in nonlinear optical (NLO) switches. Simultaneously, the rare-earth compounds 1 and 2 present bright yellow-red and bright green fluorescence, respectively, at room temperature.

18.
Mol Carcinog ; 58(6): 875-886, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30644610

RESUMO

The protein EPHB4 plays a vital role in various tumor types. However, few studies into the function of circ-EPHB4 (hsa_circ_0001730) in tumors have been conducted. This study aimed to investigate the functions of circ-EPHB4 and the underlying mechanism of circ-EPHB4 in regulating hepatocellular carcinoma (HCC). The expression of circ-EPHB4 was found to be downregulated in HCC tumor tissues, whereas circ-EPHB4 overexpression suppressed cell viability, induced apoptosis, and inhibited cell migration and invasion in Huh7 and HepG2 cells. circ-EPHB4 levels were negatively correlated with tumor weight, size, and metastasis foci in nude mouse models, suggesting circ-EPHB4 inhibits tumorigenesis, tumor development, and metastasis. In addition, HIF-1α and PI3K-AKT pathways were markedly affected by circ-EPHB4 overexpression. HIF-1α could potentially be the target of circ-EPHB4. By overexpressing both HIF-1α and circ-EPHB4, the antitumor effect of circ-EPHB4 should be most probably correlated with HIF-1α. In conclusion, circ-EPHB4 is a tumor inhibitor in HCC and functions by inhibiting HIF-1α expression.


Assuntos
Carcinoma Hepatocelular/patologia , Perfilação da Expressão Gênica/métodos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Neoplasias Hepáticas/patologia , RNA/genética , Animais , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Masculino , Camundongos , Camundongos Nus , Transplante de Neoplasias , RNA Circular
19.
Inorg Chem ; 58(15): 9733-9737, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31283197

RESUMO

The hybrid organic-inorganic materials have received extraordinary attention from the academic community not only because of their natural chemical tunability but also because of their potential in producing exotic physical properties. However, these characteristics are usually caused by the phase transition of materials under changing of external terms, and it is crucial to fully understand their origins. Here, we research an unusual phase transition near room temperature between two ordered phases in a one-dimensional (1D) hybrid organic-inorganic material of Sb|||-based [(CH2)3NH2S]2SbCl5 (1). This phase transition is caused by collective actions, including the primary variation in the bonds of inorganic five-coordinated tetragonal pyramids, displacement and rotation of organic and inorganic components, along with concurrent hydrogen bonds transformation. Afterward, we observe a significant dielectric anomaly at low frequencies between low and high temperatures. This attributed to the fact that two phases coexist with the lessening temperature, which means that a small number of high-temperature features remained but did not occur during the heating process. These findings offer an avenue for inventing a fresh phase transition and dielectric switch hybrid materials, which further open up the prospect for their practical application.

20.
Int J Mol Sci ; 20(14)2019 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-31336784

RESUMO

The main mechanistic function of most chemotherapeutic drugs is mediated by inducing mitochondria-dependent apoptosis. Tumor cells usually respond to upregulate autophagy to eliminate impaired mitochondria for survival. Hypothetically, inhibiting autophagy might promote mitochondria-dependent apoptosis, thus enhancing the efficacy of chemotherapeutic therapies. We previously identified N-methylparoxetine (NMP) as an inducer of mitochondrial fragmentation with subsequent apoptosis in non-small cell lung cancer (NSCLC) cells. We discovered that ROS was accumulated in NMP-treated NSCLC cells, followed by c-Jun N-terminal kinase (JNK) and p38 MAP kinase (p38) activation. This was reversed by the application of a reactive oxygen species (ROS) scavenger, N-acetylcysteine (NAC), leading to a reduction in apoptosis. Our data suggested that NMP induced apoptosis in NSCLC cells by activating mitogen-activated protein kinase (MAPK) pathway. We further speculated that the remarkable increase of ROS in NMP-treated NSCLC cells might result from an inhibition of autophagy. Our current data confirmed that NMP blocked autophagy flux at late stage wherein lysosomal acidification was inhibited. Taken together, this study demonstrated that NMP could exert dual apoptotic functions-mitochondria impairment and, concomitantly, autophagy inhibition. NMP-related excessive ROS accumulation induced apoptosis by activating the MAPK pathway in NSCLC cells.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Neoplasias Pulmonares/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Paroxetina/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Lisossomos/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Estrutura Molecular , Paroxetina/análogos & derivados , Paroxetina/química , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa