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1.
Phys Chem Chem Phys ; 24(13): 7713-7722, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-34909807

RESUMO

Novel carbon based "X-type" graphene nanoribbons (GNRs) with azulenes were designed for applications in nonlinear optics in the present work, and the second order nonlinear optical (NLO) properties of those X-type GNRs were predicted using the sum-over-states (SOS) model. The GNRs with edge states are feasibly polarized. The effects of zigzag edges on the NLO properties of GNRs are scrutinized by passivation, and the electronic structures of GNRs are modulated with heteroatoms at the zigzag edges for improved stability and NLO properties. Those nanomaterials were further functionalized with electron-donating and electron-withdrawing groups (NH2/NO2) to enhance the NLO responses, and the connection of those functional groups at the azulene ends play a determinant role in the enhancement of the NLO properties of those X-type nanoribbons, e.g., the static first hyperpolarizability (〈ß0〉) changes from -783.23 × 10-30 esu to -1421.98 × 10-30 esu. The mechanism of such an enhancement has been investigated. Through two-dimensional second order NLO spectra simulations, particularly besides the strong electro-optical Pockels effect and optical rectification responses, strong electronic sum frequency generations and difference frequency generations are observed in those GNRs. The strong second order NLO responses of those GNRs in the visible light region bring about potential applications of these carbon nanomaterials in nonlinear nanophotonic devices and biological nonlinear optics.

2.
Phys Chem Chem Phys ; 24(31): 18529-18542, 2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-35899847

RESUMO

The recently synthesized triangulenes with non-bonding edge states could have broad potential applications in magnetics, spintronics and electro-optics if they have appropriate electronic structure modulation. In the present work, strategies based on molecular orbital theory through heteroatom doping are proposed to redistribute, reduce or eliminate the spin of triangulenes for novel functional materials design, and the role of B, N, NBN, and BNB in such intended electronic structure manipulation is scrutinized. π-Extended triangulenes with tunable electronic properties could be potential nonlinear optical (NLO) materials with appropriate inhibition of their polyradical nature. The elimination of spin is achieved by B, N, NBN, and BNB doping with the intended geometric arrangement for enhanced polarity. Intended doping of BNB results in an optimal structure with large static first hyperpolarizability (〈ß0〉) as well as strong Hyper-Rayleigh scattering (HRS) ßHRS(-2ω; ω, ω) (ω = 1064.0 nm), TG7-BNB-ba with a large 〈ß0〉 (18.85 × 10-30 esu per heavy atom) and ßHRS (1.15 × 10-28 esu per heavy atom) much larger than that of a synthesized triangular molecule (1.12 × 10-30 esu of 〈ß0〉 per heavy atom and 5.04 × 10-30 esu of ßHRS per heavy atom). The strong second order NLO responses in the near-infrared and visible regions, particularly the strong sum frequency generation, make these B or (and) N doped triangulenes promising candidates for the fabrication of novel carbon-based optoelectronic devices and micro-NLO devices.

3.
Phys Chem Chem Phys ; 22(25): 14225-14235, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32555864

RESUMO

The third order static and dynamic nonlinear optical (NLO) responses of Ih symmetry fullerenes (C60, C240, and C540) and fullerene onions (C60@C240 and C60@C240@C540) are predicted using the ZINDO method and the sum-over-states model. The static second hyperpolarizability of Ih symmetry fullerenes increases exponentially with fullerene size [from 10.00 × 10-34 esu in C60 to 3266.74 × 10-34 esu ≈ γ0(C60) × 92.63 in C540]. The external fields of strong third order NLO responses of Ih symmetry fullerenes change from ultra-violet (C60) to the visible region (C540) as the fullerene size increases. The outer layer fullerene in the fullerene onions has dominant contributions to the third order NLO properties of the fullerene onions, and the inter-shell charge-transfer excitations have conspicuous contributions to the third order NLO properties. The two-dimensional two-photon absorption spectra of C60 and C240 show that those fullerenes have strong two-photon absorptions in the visible region with short wavelength and in the ultra-violet region.

4.
Acta Pharmacol Sin ; 41(9): 1223-1233, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32242118

RESUMO

Receptor-interacting protein 1 (RIP1, also known as RIPK1) is not only a tumor-promoting factor in several cancers but also mediates either apoptosis or necroptosis in certain circumstances. In this study we investigated what role RIP1 plays in human ovarian cancer cells. We showed that knockout (KO) of RIP1 substantially suppressed cell proliferation, accompanied by the G2/M checkpoint arrest in two human ovarian cancer cell lines SKOV3 and A2780. On the other hand, RIP1 KO remarkably attenuated cisplatin-induced cytotoxicity, which was associated with reduction of the apoptosis markers PARP cleavage and the necroptosis marker phospho-MLKL. We found that RIP1 KO suppressed cisplatin-induced ROS accumulation in both SKOV3 and A2780 cells. ROS scavenger BHA, apoptosis inhibitor Z-VAD or necroptosis inhibitor NSA could effectively suppress cisplatin's cytotoxicity in the control cells, suggesting that ROS-mediated apoptosis and necroptosis were involved in cisplatin-induced cell death. In addition, blocking necroptosis with MLKL siRNA effectively attenuated cisplatin-induced cytotoxicity. In human ovarian cancer A2780 cell line xenograft nude mice, RIP1 KO not only significantly suppressed the tumor growth but also greatly attenuated cisplatin's anticancer activity. Our results demonstrate a dual role of RIP1 in human ovarian cancer: it acts as either a tumor-promoting factor to promote cancer cell proliferation or a tumor-suppressing factor to facilitate anticancer effects of chemotherapeutics such as cisplatin.


Assuntos
Apoptose/fisiologia , Proliferação de Células/fisiologia , Pontos de Checagem da Fase G2 do Ciclo Celular/fisiologia , Necroptose/fisiologia , Neoplasias Ovarianas/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/deficiência , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Cisplatino/farmacologia , Feminino , Técnicas de Inativação de Genes , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Necroptose/efeitos dos fármacos , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Paclitaxel/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/genética
5.
Immunol Cell Biol ; 97(2): 165-177, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30242904

RESUMO

Interleukin (IL)-25 is a cytokine that has previously been shown to have a protective role against nonalcoholic fatty liver disease (NAFLD), which is associated with the induction of M2 macrophage differentiation. However, the direct relationships between IL-25 expression regulation, M2 induction and NAFLD remain unknown. In this study, we demonstrate that IL-25 promotes hepatic macrophage differentiation into M2a macrophages both in vivo and in vitro via the IL-13/STAT6 pathway. M2 macrophages that were differentiated in vitro were able to ameliorate high-fat diet HFD-induced hepatic steatosis. Furthermore, we found that IL-25 treatment, both in vitro and in vivo, promotes direct binding of STAT6 to the IL-25 gene promoter region. This binding of STAT6 in response to IL-25 treatment also resulted in the increase of IL-25 expression in hepatocytes. Together, these findings identify IL-25 as a protective factor against HFD-induced hepatic steatosis by inducing an increase of IL-25 expression in hepatocytes and through promotion of M2a macrophage production.


Assuntos
Fígado Gorduroso/prevenção & controle , Interleucina-17/metabolismo , Ativação de Macrófagos/efeitos dos fármacos , Fator de Transcrição STAT6/genética , Fator de Transcrição STAT6/metabolismo , Transdução de Sinais/fisiologia , Animais , Dieta Hiperlipídica , Fígado Gorduroso/etiologia , Fígado Gorduroso/metabolismo , Hepatócitos/metabolismo , Interleucina-13/metabolismo , Interleucina-17/farmacologia , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/metabolismo , Proteínas Recombinantes/farmacologia
7.
Yao Xue Xue Bao ; 51(1): 75-9, 2016 Jan.
Artigo em Zh | MEDLINE | ID: mdl-27405165

RESUMO

The study was designed to explore the drug-drug interactions mechanisms mediated by OATP1B1 between traditional Chinese medicine Danshensu and rosuvastatin. First, the changes of rosuvastatin pharmacokinetics were investigated in presence of Danshensu in rats. Then, the primary rat hepatocytes model was established to explore the effects of Danshensu on the uptake of rosuvastatin by hepatocytes. Finally, HEK293T cells with overexpression of OATP1B1*a and OATP1B1*5 were established using a lentiviral delivery system to explore the effects of Danshensu on the uptake of rosuvastatin. Rosuvastatin pharmacokinetic parameters of C(max0, AUCO(0-t), AUC(0-∞) were increased about 123%, 194% and 195%, by Danshensu in rats, while the CL z/F value was decreased by 60%. Uptake of rosuvastatin in the primary rat hepatocytes was decreased by 3.13%, 41.15% and 74.62%, respectively in the presence of 20, 40 and 80 µmol x L(-1) Danshensu. The IC50 parameters was (53.04 ± 2.43) µmol x L(-1). The inhibitory effect of Danshensu on OATP1B1 mediated transport of rosuvastatin was related to the OATP1B1 gene type. In OATP1B1*5-HEK293T mutant cells, transport of rosuvastatin were reduced by (39.11 ± 4.94)% and (63.61 ± 3.94)%, respectively, by Danshensu at 1 and 10 µmol x L(-1). While transport of rosuvastatin was reduced by (8.22 ± 2.40)% and (11.56 ± 3.04)% and in OATP1B1*1a cells, respectively. Danshensu significantly altered the pharmacokinetics of rosuvastatin in rats, which was related to competitive inhibition of transport by OATPJBI. Danshensu exhibited a significant activity in the inhibition of rosuvastatin transport by OATP1B1*5-HEK293T, but not by OATP1B1*1a, suggesting a dependence on OATP1B1 sequence.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Hepatócitos/efeitos dos fármacos , Lactatos/farmacologia , Transportadores de Ânions Orgânicos/metabolismo , Rosuvastatina Cálcica/farmacologia , Animais , Interações Medicamentosas , Células HEK293 , Hepatócitos/metabolismo , Humanos , Transportador 1 de Ânion Orgânico Específico do Fígado , Ratos
8.
Int J Mol Sci ; 15(2): 2761-72, 2014 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-24552875

RESUMO

Multidrug-resistant breast cancers have limited and ineffective clinical treatment options. This study aimed to develop PLGA nanoparticles containing a synergistic combination of vincristine and verapamil to achieve less toxicity and enhanced efficacy on multidrug-resistant breast cancers. The 1:250 molar ratio of VCR/VRP showed strong synergism with the reversal index of approximately 130 in the multidrug-resistant MCF-7/ADR cells compared to drug-sensitive MCF-7 cells. The lyophilized nanoparticles could get dispersed quickly with the similar size distribution, zeta potential and encapsulation efficiency to the pre-lyophilized nanoparticles suspension, and maintain the synergistic in vitro release ratio of drugs. The co-encapsulated nanoparticle formulation had lower toxicity than free vincristine/verapamil combinations according to the acute-toxicity test. Furthermore, the most effective tumor growth inhibition in the MCF-7/ADR human breast tumor xenograft was observed in the co-delivery nanoparticle formulation group in comparison with saline control, free vincristine, free vincristine/verapamil combinations and single-drug nanoparticle combinations. All the data demonstrated that PLGANPs simultaneously loaded with chemotherapeutic drug and chemosensitizer might be one of the most potential formulations in the treatment of multidrug-resistant breast cancer in clinic.


Assuntos
Antineoplásicos/química , Portadores de Fármacos/química , Ácido Láctico/química , Nanopartículas/química , Ácido Poliglicólico/química , Animais , Antineoplásicos/toxicidade , Apoptose/efeitos dos fármacos , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Células MCF-7 , Camundongos Endogâmicos BALB C , Camundongos Nus , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Transplante Heterólogo , Verapamil/química , Verapamil/toxicidade , Vincristina/química , Vincristina/toxicidade
9.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 45(6): 893-7, 2014 Nov.
Artigo em Zh | MEDLINE | ID: mdl-25571710

RESUMO

OBJECTIVE: To explore the reversal effect of (- )-5-N-acetylardeemin on adriamycin resistance in multidrug-resistant cancer cells including human breast cancer cells MCF-7/Adr and human non-small cell lung cancer cells A549/Adr in vitro. METHODS: The multidrug-resistant cancer cells MCF-7/Adr, A549/Adr and their respective parental cells were treated with different concentrations of (- )-5-N-acetylardeemin and adriamycin individually or in combination. Cell death was detected based on the release of lactate dehydrogenase (LDH) using a cytotoxicity detection kit. Intracellular accumulation of adriamycin was measured by the detection of fluorescence intensity of cell lysates using microplate reader. The expression of P-glycoprotein (P-gp) was evaluated by Western blot. RESULTS: (-)-5-N-acetylardeemin significantly reversed the adriamycin resistance in MCF-7/Adr and A549/ Adr in a dose-dependent manner, and the reversal folds were 10. 8 in MCF-7/Adr cells and 20.1 in A549/Adr cells with the treatment of 10 µmol/L (-)-5-N acetylardeemin. (- )-5-N-acetylardeemin also enhanced the sensitivity of parental MCF-7 and A549 cells to adriamycin. The fluorescence intensity in both MCF-7/Adr and A549/Adr cells, which reflected the intracellular accumulation of adriamycin, were significantly enhanced by ( -)5-N- acetylardeemin in a dose-dependent manner. The expressions of P-gp in MCF-7/Adr and A549/Adr cells were significantly inhibited by (- )-5-N-acetylardeemin. CONCLUSION: (- )5-N-acetylardeemin could reverse the multidrug resistance in cancer cells through inhibiting the expression of P-gp and enhancing the intracellular accumulation of cytotoxic drug.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Doxorrubicina/farmacologia , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral/efeitos dos fármacos , Humanos , Pirimidinonas/farmacologia
10.
Spectrochim Acta A Mol Biomol Spectrosc ; 323: 124890, 2024 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-39098295

RESUMO

Porphyrins are widely used as potential nonlinear optical (NLO) materials because of their highly delocalized π electrons and feasible synthesis and functionalization with broad biological applications. A variety of linear and cyclic porphyrin derivatives have been synthesized, and the correlation between their structures and NLO properties awaits being disclosed. In this work, the electronic structures and third-order NLO properties of linear and cyclic butadiyne-linked zinc porphyrin oligomers have been studied by quantum chemical methods and sum-over-states model. The static second hyperpolarizability (<γ0>) increases exponentially with the number of zinc porphyrin units ([<γ0>n] = 0.67[<γ0>1]n2.63, n = 2 âˆ¼ 6) in linear π-conjugated oligomers, and the <γ0> of the linear hexamer is about 74 times that of the monomer. Such enhancement of <γ0> in linear oligomers originates from closely-lying frontier molecular orbitals available for low energy electron excitations and strong charge transfer-based excitations across porphyrins. The <γ0>s of cyclic porphyrins are lower than that of the linear hexamer, though the interaction between the ring and the ligand enhances the <γ0> of some cyclic zinc porphyrin complexes. The large two-photon absorption cross sections confer on these zinc porphyrin derivatives excellent candidates for two-photon absorption applications.

11.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 44(6): 859-64, 2013 Nov.
Artigo em Zh | MEDLINE | ID: mdl-24490490

RESUMO

OBJECTIVE: To investigate the effect of recombinant soluble CD40 ligand (rsCD40L) on Wogonin mediated antitumor activity in cancer cells and the underlying molecular mechanisms. METHODS: Cell death was detected based on the release of lactate dehydrogenase (LDH) using a cytotoxicity detection kit. For morphological study of cell death, cells were stained with 50 microg/mL of acridine orange and 50 microg/mL of ethidium bromide and observed and photographed under a fluorescence microscope. Activation of apoptosis pathway was evaluated by Western blot. The effects of pan-caspase inhibitor Z-VAD-FMK and tumor necrosis factor alpha (TNF-alpha) neutralizing antibody on cell death induced by rsCD40L and Wogonin co-treatment were also investigated. RESULTS: rsCD40L significantly enhanced Wogonin-induced cell death of ovarian cancer cells SKOV3. A dose-dependent synergism was found with a fixed rsCD40L dose (1 microg/mL) and increased concentrations of Wogonin (5 micromol/L-15 micromol/L). rsCD40L and Wogonin co-treated cells showed typical apoptotic morphologies and enhanced activation of caspases pathway. As expected, the pan-caspase inhibitor Z-VAD-FMK inhibited synergistic cell death of rsCD40L and Wogonin co-treated SKOV3 cells. Interestingly, the TNF-alpha neutralizing antibody that blocks TNF-alpha binding to its receptor also significantly suppressed the cell death enhancing effect, indicating that autocrine TNF-alpha played a role of sensitization. CONCLUSION: rscCD40L sensitizes cancer cells to wogonin-mediated apoptosis, which may involve autocrine of TNF-alpha, and the combination of rsCD40L and Wogonin may have a potential for cancer therapy.


Assuntos
Apoptose/efeitos dos fármacos , Ligante de CD40/farmacologia , Flavanonas/farmacologia , Neoplasias Ovarianas/patologia , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Feminino , Humanos , Neoplasias Ovarianas/metabolismo , Proteínas Recombinantes/farmacologia , Scutellaria/química , Fator de Necrose Tumoral alfa/metabolismo
12.
Cancer Sci ; 103(2): 197-202, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22010829

RESUMO

Activation of CD40, a member of the tumor necrosis factor receptor (TNF-R) family, results in growth inhibition or apoptosis in some tumor cells, making CD40 a potential antitumor therapeutic target. Although it is known that CD40 is able to induce tumor necrosis factor-alpha (TNF-α) secretion and potentiate cisplatin's anticancer activity, whether TNF-α induction is involved in sensitizing cisplatin by CD40 has not been addressed. In this report, we provide evidence substantiating an important role of autocrine TNF-α in potentiation of cisplatin-induced apoptosis by recombinant soluble CD40 ligand (rsCD40L) in different human cancer cell lines. Activation of CD40 by rsCD40L induces two phases of autocrine TNF-α: the rapid early phase involving p38 MAP kinase and the robust and persistent late phase through enhanced tnf-α gene transcription. Blocking TNF-α with either a specific TNFR1 siRNA or a neutralizing anti-TNF-α antibody dramatically attenuated the potentiation effect of rsCD40L on cisplatin-induced cancer cell death. These results reveal an important role of TNF-α induction in CD40's chemosensitization activity and suggest that modulating TNF-α autocrine from cancer cells is an effective option for increasing the anticancer value of chemotherapeutics such as cisplatin.


Assuntos
Antineoplásicos/farmacologia , Apoptose , Antígenos CD40/metabolismo , Cisplatino/farmacologia , Neoplasias/patologia , Fator de Necrose Tumoral alfa/metabolismo , Anticorpos Neutralizantes , Ligante de CD40/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Neoplasias/metabolismo , Interferência de RNA , RNA Interferente Pequeno , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
13.
Antioxidants (Basel) ; 11(2)2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-35204170

RESUMO

Cellular redox homeostasis is crucial for normal plant growth and development. Each developmental stage of plants has a specific redox mode and is maintained by various environmental cues, oxidants, and antioxidants. Reactive oxygen species (ROS) and reactive nitrogen species are the chief oxidants in plant cells and participate in cell signal transduction and redox balance. The production and removal of oxidants are in a dynamic balance, which is necessary for plant growth. Especially during reproductive development, pollen development depends on ROS-mediated tapetal programmed cell death to provide nutrients and other essential substances. The deviation of the redox state in any period will lead to microspore abortion and pollen sterility. Meanwhile, pollens are highly sensitive to environmental stress, in particular to cell oxidative burst due to its peculiar structure and function. In this regard, plants have evolved a series of complex mechanisms to deal with redox imbalance and oxidative stress damage. This review summarizes the functions of the main redox components in different stages of pollen development, and highlights various redox protection mechanisms of pollen in response to environmental stimuli. In continuation, we also discuss the potential applications of plant growth regulators and antioxidants for improving pollen vigor and fertility in sustaining better agriculture practices.

14.
Acta Pharmacol Sin ; 32(12): 1529-36, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21986580

RESUMO

AIM: To investigate the anticancer effect of crocetin, a major ingredient in saffron, and its underlying mechanisms. METHODS: Cervical cancer cell line HeLa, non-small cell lung cancer cell line A549 and ovarian cancer cell line SKOV3 were treated with crocetin alone or in combination with vincristine. Cell proliferation was examined using MTT assay. Cell cycle distribution and sub-G(1) fraction were analyzed using flow cytometric analysis after propidium iodide staining. Apoptosis was detected using the Annexin V-FITC Apoptosis Detection Kit with flow cytometry. Cell death was measured based on the release of lactate dehydrogenase (LDH). The expression levels of p53 and p21(WAF1/Cip1) as well as caspase activation were examined using Western blot analysis. RESULTS: Treatment of the 3 types of cancer cells with crocetin (60-240 µmol/L) for 48 h significantly inhibited their proliferation in a concentration-dependent manner. Crocetin (240 µmol/L) significantly induced cell cycle arrest through p53-dependent and -independent mechanisms accompanied with p21(WAF1/Cip1) induction. Crocetin (120-240 µmol/L) caused cytotoxicity in the 3 types of cancer cells by enhancing apoptosis in a time-dependent manner. In the 3 types of cancer cells, crocetin (60 µmol/L) significantly enhanced the cytotoxicity induced by vincristine (1 µmol/L). Furthermore, this synergistic effect was also detected in the vincristine-resistant breast cancer cell line MCF-7/VCR. CONCLUSION: Ccrocetin is a potential anticancer agent, which may be used as a chemotherapeutic drug or as a chemosensitizer for vincristine.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Carotenoides/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Vincristina/farmacologia , Linhagem Celular Tumoral , Sinergismo Farmacológico , Citometria de Fluxo , Humanos , Vitamina A/análogos & derivados
15.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 42(3): 303-7, 2011 May.
Artigo em Zh | MEDLINE | ID: mdl-21826987

RESUMO

OBJECTIVE: To investigate the effect of heat shock protein 90 (HSP90) inhibitor 17-dimethylaminoethylaminogeldanamycin (17DMAG) on tumor necrosis factor alpha (TNFalpha) mediated apopotosis in cancer cells and the underlying molecular mechanisms. METHODS: Cell death treated with different concentration of 17DMAG and TNFalpha was detected based on the release of lactate dehydrogenase (LDH) using a cytotoxicity detection kit. For morphological study of cell death, cells were stained with 50 microg/mL of acridine orange and 50 microg/mL of ethidium bromide and observed and photographed under a fluorescence microscope. Activation of apoptosis and NF-kappaB pathway were evaluated on the change of caspase-8, caspase-3, poly (ADP-ribose) polymerase (PARP), receptor-interaction protein (RIP), IkappaB kinase beta (IKKbeta) and inhibitor of IkappaB (IkappaBalpha) by Western blot. RESULTS: 17DMAG sensitized cervical cancer cells HeLa and ovarian cancer cells SKOV3 to TNFalpha-induced cell death in a dose-dependent manner, which was accompanied with degradation of RIP and Ikappakappabeta, and consequent blockage of TNFalpha-induced NFkappaB activation. 17DMAG and TNFalpha cotreated cells showed typical apoptotic morphologies and enhancing of activation of caspases. CONCLUSION: 17DMAG sensitizes cancer cells to TNFalpha-mediated apoptosis through blockage of TNF-induced NF-kappaB activation, and disabling this survival signal with 17DMAG followed by TNF treatment could be an effective new therapeutic strategy for improving the anti-cancer value of TNFalpha.


Assuntos
Apoptose/efeitos dos fármacos , Benzoquinonas/farmacologia , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Lactamas Macrocíclicas/farmacologia , NF-kappa B/metabolismo , Neoplasias Ovarianas/patologia , Fator de Necrose Tumoral alfa/farmacologia , Linhagem Celular Tumoral , Feminino , Células HeLa , Humanos
16.
PLoS One ; 16(4): e0238873, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33914776

RESUMO

Organic acids and sugars are the primary components that determine the quality and flavor of loquat fruits. In the present study, major organic acids, sugar content, enzyme activities, and the expression of related genes were analyzed during fruit development in two loquat cultivars, 'JieFangZhong' (JFZ) and 'BaiLi' (BL). Our results showed that the sugar content increased during fruit development in the two cultivars; however, the organic acid content dramatically decreased in the later stages of fruit development. The differences in organic acid and sugar content between the two cultivars primarily occured in the late stage of fruit development and the related enzymes showed dynamic changes in activies during development. Phosphoenolpyruvate carboxylase (PEPC) and mNAD malic dehydrogenase (mNAD-MDH) showed higher activities in JFZ at 95 days after flowering (DAF) than in BL. However, NADP-dependent malic enzyme (NADP-ME) activity was the lowest at 95 DAF in both JFZ and BL with BL showing higher activity compared with JFZ. At 125 DAF, the activity of fructokinase (FRK) was significantly higher in JFZ than in BL. The activity of sucrose synthase (SUSY) in the sucrose cleavage direction (SS-C) was low at early stages of fruit development and increased at 125 DAF. SS-C activity was higher in JFZ than in BL. vAI and sucrose phosphate synthase (SPS) activities were similar in the two both cultivars and increased with fruit development. RNA-sequencing was performed to determine the candidate genes for organic acid and sugar metabolism. Our results showed that the differentially expressed genes (DEGs) with the greated fold changes in the later stages of fruit development between the two cultivars were phosphoenolpyruvate carboxylase 2 (PEPC2), mNAD-malate dehydrogenase (mNAD-MDH), cytosolic NADP-ME (cyNADP-ME2), aluminum-activated malate transporter (ALMT9), subunit A of vacuolar H+-ATPase (VHA-A), vacuolar H+-PPase (VHP1), NAD-sorbitol dehydrogenase (NAD-SDH), fructokinase (FK), sucrose synthase in sucrose cleavage (SS-C), sucrose-phosphate synthase 1 (SPS1), neutral invertase (NI), and vacuolar acid invertase (vAI). The expression of 12 key DEGs was validated by quantitative reverese transcription PCR (RT-qPCR). Our findings will help understand the molecular mechanism of organic acid and sugar formation in loquat, which will aid in breeding high-quality loquat cultivars.


Assuntos
Eriobotrya/genética , Frutas/genética , Regulação da Expressão Gênica de Plantas , Ácidos/metabolismo , Metabolismo dos Carboidratos , Carboidratos/genética , Eriobotrya/crescimento & desenvolvimento , Eriobotrya/metabolismo , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Perfilação da Expressão Gênica , Genes de Plantas , Transcriptoma
17.
Clin Transl Gastroenterol ; 11(12): e00285, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33512812

RESUMO

INTRODUCTION: Compared with endoscopic variceal ligation (EVL), cap-assisted endoscopic sclerotherapy (CAES) improves efficacy in the treatment of small esophageal varices (EVs) but has not been evaluated in the management of medium EVs. The aim of this study was to compare CAES with EVL in the long-term management of patients exhibiting cirrhosis with medium EVs and a history of esophageal variceal bleeding (EVB), with respect to variceal eradication and recurrence, adverse events, rebleeding, and survival. METHODS: Cirrhotic patients with medium EVs and a history of EVB were divided randomly into EVL and CAES groups. EVL or CAES was repeated each month until variceal eradication. Lauromacrogol was used as a sclerosant. Patients were followed up until 1 year after eradication. RESULTS: In total, 240 patients (age: 51.1 ± 10.0 years; men: 70.8%) were included and randomized to the EVL and CAES groups. The recurrence rate of EVs was much lower in the CAES group than in the EVL group (13.0% vs 30.7%, P = 0.001). The predictors for variceal recurrence were eradication by EVL (hazard ratio [HR]: 2.37, P = 0.04), achievement of complete eradication (HR: 0.27, P < 0.001), and nonselective ß-blocker response (HR: 0.32, P = 0.003). There was no significant difference in the rates of eradication, rebleeding, requirement for alternative therapy, and mortality or the incidence of complications between groups. DISCUSSION: CAES reduces the recurrence rate of EVs with comparable safety to that of EVL in the long-term management of patients presenting cirrhosis with medium EVs and a history of EVB.


Assuntos
Varizes Esofágicas e Gástricas/terapia , Esofagoscopia/métodos , Ligadura/métodos , Complicações Pós-Operatórias/epidemiologia , Escleroterapia/métodos , Adulto , Varizes Esofágicas e Gástricas/diagnóstico , Varizes Esofágicas e Gástricas/etiologia , Esofagoscopia/efeitos adversos , Humanos , Incidência , Ligadura/efeitos adversos , Cirrose Hepática/complicações , Cirrose Hepática/terapia , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Estudos Prospectivos , Recidiva , Escleroterapia/efeitos adversos , Prevenção Secundária , Índice de Gravidade de Doença , Resultado do Tratamento
18.
J Dig Dis ; 21(3): 170-178, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32031737

RESUMO

OBJECTIVES: To investigate whether second-look endoscopy (SLE)-guided therapy could be used to prevent post-endoscopic variceal ligation (EVL) early bleeding. METHODS: Consecutive cirrhotic patients with large esophageal varices (EV) receiving successful EVL for acute variceal bleeding (AVB) or secondary prophylaxis were enrolled. The patients were randomized into a SLE group and a non-SLE group (NSLE) 10 days after EVL. Additional endoscopic interventions as well as proton pump inhibitors and octreotide administration were applied based on the SLE findings. The post-EVL early rebleeding and mortality rates were compared between the two groups. RESULTS: A total of 252 patients were included in the final analysis. Post-EVL early rebleeding (13.5% vs 4.8%, P = 0.016) and bleeding-caused mortality (4.8% vs 0%, P = 0.013) were more frequently observed in the NSLE group than in the SLE group. However, post-EVL early rebleeding and mortality rates were reduced by SLE in patients receiving EVL for AVB only but not in those receiving secondary prophylaxis. Patients with Child-Pugh classification B to C at randomization (hazard ratio [HR] 8.77, P = 0.034), AVB at index EVL (HR 3.62, P = 0.003), discontinuation of non-selective ß-blocker after randomization (HR 4.68, P = 0.001) and non-SLE (HR 2.63, P = 0.046) were more likely to have post-EVL early rebleeding. No serious adverse events occurred during SLE. CONCLUSION: SLE-guided therapy reduces post-EVL early rebleeding and mortality rates in cirrhotic patients with large EV receiving EVL for AVB.


Assuntos
Sedação Consciente , Endoscopia/mortalidade , Hemorragia Gastrointestinal/cirurgia , Hemorragia Pós-Operatória/cirurgia , Cirurgia de Second-Look/mortalidade , Doença Aguda , Adulto , Endoscopia/métodos , Varizes Esofágicas e Gástricas/cirurgia , Feminino , Hemorragia Gastrointestinal/mortalidade , Hemorragia Gastrointestinal/prevenção & controle , Humanos , Ligadura/efeitos adversos , Cirrose Hepática/complicações , Masculino , Pessoa de Meia-Idade , Hemorragia Pós-Operatória/mortalidade , Hemorragia Pós-Operatória/prevenção & controle , Recidiva , Cirurgia de Second-Look/métodos , Prevenção Secundária , Índice de Gravidade de Doença , Resultado do Tratamento
19.
Mitochondrial DNA B Resour ; 5(1): 269-270, 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-33366516

RESUMO

Eriobotrya japonica is an evergreen fruit tree originating in southeastern China. Its fruit is juicy with a pleasant taste and considerable medical value. However, there is no complete mitochondrial (cmt) genome resource for this species. This is the first report of the cmt genome of Eriobotrya japonica from southeastern China. The whole cmt genome was 434,980 bp in size with 37.80% GC content. The cmt genome of Eriobotrya japonica contains 41 protein-coding genes, 22 tRNA genes, and 3 rRNA genes. A phylogenetic maximum-likelihood (ML) tree was constructed based on 22 mitochondrial genomes from plant species. Eriobotrya japonica grouped closely with other Rosaceae species, which provides strong support for the traditional classification.

20.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 39(2): 298-301, 2008 Mar.
Artigo em Zh | MEDLINE | ID: mdl-18630708

RESUMO

OBJECTIVE: To research the reliable method for the isolation and culture of Kupffer cell in BALB/c mouse by mixed enzyme. METHODS: Kupffer cells were isolated from liver by in situ perfusion and digestion with 0.1% IV collagenase, 0.2% pronase and 0.01% Dnase I, and by percoll density gradient centrifugation. Kupffer cells were identified by fluorescence microscope, immunohistochemistry and cell endocytosis effect. RESULTS: Kupffer cells were isolated successfully with high purity, the yield of (2-3) 10(6)/per mouse liver and the identification that 0.4% trypan blue indicated that the cells survival rate and purity were more than 96% and more than 92% respectively. The shape of Kupffer cell appeared to be multiplicity, irregularity, polygon and multiangular. Kupffer cells showed lysozyme positive by immunohistochemistry staining. And particles of India ink were found in cytoplasm. CONCLUSION: Here described technique for isolation and culture of Kupffer cells is simple and reliable, and can be used for preparing Kupffer cells with high yield, activity and purity.


Assuntos
Separação Celular/métodos , Células de Kupffer/citologia , Animais , Forma Celular , Sobrevivência Celular , Células Cultivadas , Colagenases/metabolismo , Imuno-Histoquímica , Células de Kupffer/enzimologia , Fígado/citologia , Camundongos , Camundongos Endogâmicos BALB C , Muramidase/metabolismo , Pronase/metabolismo , Reprodutibilidade dos Testes
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