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1.
New Phytol ; 243(4): 1424-1439, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38922886

RESUMEN

Acyl-CoA-Binding Proteins (ACBPs) bind acyl-CoA esters and function in lipid metabolism. Although acbp3-1, the ACBP3 mutant in Arabidopsis thaliana ecotype Col-0, displays normal floral development, the acbp3-2 mutant from ecotype Ler-0 characterized herein exhibits defective adaxial anther lobes and improper sporocyte formation. To understand these differences and identify the role of ERECTA in ACBP3 function, the acbp3 mutants and acbp3-erecta (er) lines were analyzed by microscopy for anther morphology and high-performance liquid chromatography for lipid composition. Defects in Landsberg anther development were related to the ERECTA-mediated pathway because the progenies of acbp3-2 × La-0 and acbp3-1 × er-1 in Col-0 showed normal anthers, contrasting to that of acbp3-2 in Ler-0. Polymorphism in the regulatory region of ACBP3 enabled its function in anther development in Ler-0 but not Col-0 which harbored an AT-repeat insertion. ACBP3 expression and anther development in acbp3-2 were restored using ACBP3pro (Ler)::ACBP3 not ACBP3pro (Col)::ACBP3. SPOROCYTELESS (SPL), a sporocyte formation regulator activated ACBP3 transcription in Ler-0 but not Col-0. For anther development, the ERECTA-related role of ACBP3 is required in Ler-0, but not Col-0. The disrupted promoter regulatory region for SPL binding in Col-0 eliminates the role of ACBP3 in anther development.


Asunto(s)
Alelos , Proteínas de Arabidopsis , Arabidopsis , Flores , Regulación de la Expresión Génica de las Plantas , Regiones Promotoras Genéticas , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Inhibidor de la Unión a Diazepam/metabolismo , Inhibidor de la Unión a Diazepam/genética , Ecotipo , Flores/genética , Flores/crecimiento & desarrollo , Mutación/genética , Fenotipo , Polimorfismo Genético , Regiones Promotoras Genéticas/genética
2.
Chem Biol Interact ; 395: 111013, 2024 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-38663798

RESUMEN

Ulcerative colitis is a chronic disease with colonic mucosa injury. Nitazoxanide is an antiprotozoal drug in clinic. Nitazoxanide and its metabolite tizoxanide have been demonstrated to activate AMPK and inhibit inflammation, therefore, the aim of the present study is to investigate the effect of nitazoxanide on dextran sulfate sodium (DSS)-induced colitis and the underlying mechanism. Oral administration of nitazoxanide ameliorated the symptoms of mice with DSS-induced colitis, as evidenced by improving the increased disease activity index (DAI), the decreased body weight, and the shortened colon length. Oral administration of nitazoxanide ameliorated DSS-induced intestinal barrier dysfunction and reduced IL-6 and IL-17 expression in colon tissues. Mechanistically, nitazoxanide and its metabolite tizoxanide treatment activated AMPK and inhibited JAK2/STAT3 signals. Nitazoxanide and tizoxanide treatment increased caudal type homeobox 2 (CDX2) expression, increased alkaline phosphatase (ALP) activity and promoted tight junctions in Caco-2 cells. Nitazoxanide and tizoxanide treatment restored the decreased zonula occludens-1(ZO-1) and occludin protein levels induced by LPS or IL-6 in Caco-2 cells. On the other hand, nitazoxanide and tizoxanide regulated macrophage bias toward M2 polarization, as evidenced by the increased arginase-1expression in bone marrow-derived macrophages (BMDM). Nitazoxanide and tizoxanide reduced the increased IL-6, iNOS and CCL2 pro-inflammatory gene expressions and inhibited JAK2/STAT3 activation in BMDM induced by LPS. In conclusion, nitazoxanide protects against DSS-induced ulcerative colitis in mice through improving intestinal barrier and inhibiting inflammation and the underlying mechanism involves AMPK activation and JAK2/STAT3 inhibition.


Asunto(s)
Colitis Ulcerosa , Sulfato de Dextran , Mucosa Intestinal , Nitrocompuestos , Factor de Transcripción STAT3 , Tiazoles , Animales , Tiazoles/farmacología , Tiazoles/uso terapéutico , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/tratamiento farmacológico , Colitis Ulcerosa/patología , Colitis Ulcerosa/metabolismo , Nitrocompuestos/farmacología , Ratones , Humanos , Células CACO-2 , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Sulfato de Dextran/toxicidad , Factor de Transcripción STAT3/metabolismo , Masculino , Janus Quinasa 2/metabolismo , Proteínas Quinasas Activadas por AMP/metabolismo , Inflamación/tratamiento farmacológico , Colon/efectos de los fármacos , Colon/patología , Colon/metabolismo , Ratones Endogámicos C57BL , Transducción de Señal/efectos de los fármacos , Óxido Nítrico Sintasa de Tipo II/metabolismo , Interleucina-6/metabolismo , Modelos Animales de Enfermedad
3.
Sensors (Basel) ; 23(10)2023 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-37430637

RESUMEN

Telemetry data are the most important basis for ground operators to assess the status of satellites in orbit, and telemetry data-based anomaly detection has become a key tool to improve the reliability and safety of spacecrafts. Recent research on anomaly detection focuses on constructing a normal profile of telemetry data using deep learning methods. However, these methods cannot effectively capture the complex correlations between the various dimensions of telemetry data, and thus cannot accurately model the normal profile of telemetry data, resulting in poor anomaly detection performance. This paper presents CLPNM-AD, contrastive learning with prototype-based negative mixing for correlation anomaly detection. The CLPNM-AD framework first employs an augmentation process with random feature corruption to generate augmented samples. Following that, a consistency strategy is employed to capture the prototype of samples, and then prototype-based negative mixing contrastive learning is used to build a normal profile. Finally, a prototype-based anomaly score function is proposed for anomaly decision-making. Experimental results on public datasets and datasets from the actual scientific satellite mission show that CLPNM-AD outperforms the baseline methods, achieves up to 11.5% improvement based on the standard F1 score and is more robust against noise.

4.
Heliyon ; 9(4): e14812, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37025849

RESUMEN

Economic resilience has been a popular issue in recent years. Along with the consideration of severe shocks caused by the financial crisis of 2007-2008 and globalization of industry and the upgradation of knowledge and technology, economic resilience has brought in much attention. About 50 years of development of planned industrial parks in Taiwan has resulted in considerable economic scale; however, due to changes in interior demands and the exterior environment with time, rearrangement and industrial transformation have made the development of industrial parks difficult. Accordingly, the resilience of planned industrial parks in Taiwan, when encountering a variety of shocks, need to be reviewed and examined. This study selects 12 planned industrial parks from Tainan and Kaohsiung, in southern Taiwan, as subjects and had a complete understanding of economic resilience and factors that influence economic resilience from literature reviews. Four quadrant model constituted by the indicators of economic resistance and recovery as well as discriminant analysis are implemented to analyze the resilience of industrial parks with different backgrounds and various shocks, as well as the elements influencing the resilience. Analytical results indicate that planned industrial parks with industrial structures based on specialized variety or with a steady input of knowledge and innovation to research and development benefited the industrial parks in better resilience, while complete infrastructure planning and governance are fundamental conditions for resilience.

5.
Front Plant Sci ; 12: 632503, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33664761

RESUMEN

[This corrects the article DOI: 10.3389/fpls.2018.00002.].

6.
Sci Rep ; 9(1): 15838, 2019 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-31676873

RESUMEN

This study aimed to assess the prevalence and related factors of obesity-related hypertension among adults aged 40 to 79 years in Southwest China. From September 2013 to March 2014, a multi-stage, stratified sampling method was conducted on 10,589 people aged 40 to 79 years and living in Chengdu and Chongqing investigated by using a questionnaire and performing physical and biochemical measurements. The prevalence of obesity-related hypertension and hypertension overall (systolic ≥130 mmHg and/or diastolic ≥80 mmHg or treated hypertension) was 22.8% and 57.4%, respectively, among all participants. For obesity-related hypertension, the prevalence was higher in women than in men (24.7% versus 19.4%, p < 0.001). For people in the age ranges of 40-49, 50-59, 60-69, and ≥70, the prevalence of obesity-related hypertension were 11.8%, 22.6%, 30.7%, and 36.6%, respectively. Participants with obesity-related hypertension as opposed to those with non-obesity-related hypertension had a higher prevalence of hypertriglyceridemia, high low-density lipoprotein cholesterolemia, diabetes, and hyperuricemia (all p < 0.05). Multivariate logistic regression analysis showed that age, female gender, current smoking, hypertriglyceridemia, diabetes and family history of hypertension were all positively correlated with obesity-related hypertension, whereas higher education level and having spouse were negatively correlated with obesity-related hypertension. The prevalence of obesity-related hypertension was high among adults aged 40 to 79 years in Southwest China. Cardiometabolic abnormalities among participants with obesity-related hypertension were more serious and frequently present than in those with non-obesity-related hypertension. Aggressive and holistic strategies aiming at the prevention and treatment of obesity-related hypertension are needed.


Asunto(s)
Hipertensión , Obesidad , Adulto , Factores de Edad , Anciano , China/epidemiología , Femenino , Humanos , Hipertensión/epidemiología , Hipertensión/fisiopatología , Masculino , Persona de Mediana Edad , Obesidad/epidemiología , Obesidad/fisiopatología , Prevalencia , Factores Sexuales
7.
Chem Commun (Camb) ; 55(81): 12172-12175, 2019 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-31544179

RESUMEN

Phthalimide-based "D-N-A" emitters o-AI-Cz, m-AI-Cz and p-AI-Cz showed TADF and RTP properties due to their small ΔEST in both film and crystalline states. In particular, o-AI-Cz exhibited an ultralong RTP with a lifetime of 602 ms in air and remarkable afterglow, which could allow it to be used as a security ink for application in anti-counterfeiting materials. Moreover, o-AI-Cz showed intense intramolecular interaction between the donor and the acceptor subunits, while p-AI-Cz could form regular hexagonal pores with a diameter of 13.171 Å in the solid state, which might result in their different RTP properties.

8.
J Hazard Mater ; 357: 180-186, 2018 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-29886363

RESUMEN

This study evaluated the methanogens responsible for methanogenic degradation of tetramethylammonium hydroxide (TMAH) in a continuous flow bioreactor. The enriched methanogens attained an estimated maximum specific TMAH degradation rate and half-saturation constant of 39.5 mg TMAH/gVSS/h and 820 mg/L, following the Monod-type kinetic expression for methanogenic TMAH degradation. Presence of sulfide more than 20 mg/L significantly extended lag period and slowed down specific TMAH degradation rates. The results of terminal restriction fragment length polymorphism (T-RFLP), cloning/sequencing, and quantitative real-time PCR analyses targeting on the methyl coenzyme M reductase alpha subunit (mcrA) genes retrieved from the bioreactor and batch experiments indicated that Methanomethylovorans species were the dominant methanogens responsible for methanogenic degradation of TMAH. The isolated TMAH-degrading methanogen from the bioreactor, however, was identified closely related to Methanosarcina mazei. It is likely that a very low TMAH environment in the bioreactor favored the growth of Methanomethylovorans hollandica, while the much higher TMAH in the isolation growth medium proliferated Methanosarcina mazei.


Asunto(s)
Reactores Biológicos/microbiología , Metano/metabolismo , Methanosarcinaceae/metabolismo , Compuestos de Amonio Cuaternario/metabolismo , Proteínas Bacterianas/genética , Biodegradación Ambiental , Methanosarcinaceae/genética , Oxidorreductasas/genética
9.
Front Plant Sci ; 9: 2, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29422909

RESUMEN

Oxylipins are crucial components in plant wound responses that are mobilised via the plant vasculature. Previous studies have shown that the overexpression of an Arabidopsis acyl-CoA-binding protein, AtACBP3, led to an accumulation of oxylipin-containing galactolipids, and AtACBP3pro::BETA-GLUCURONIDASE (GUS) was expressed in the phloem of transgenic Arabidopsis. To investigate the role of AtACBP3 in the phloem, reverse transcription-polymerase chain reaction and western blot analysis of phloem exudates from the acbp3 mutant and wild type revealed that the AtACBP3 protein, but not its mRNA, was detected in the phloem sap. Furthermore, micrografting demonstrated that AtACBP3 expressed from the 35S promoter was translocated from shoot to root. Subsequently, AtACBP3 was localised to the companion cells, sieve elements and the apoplastic space of phloem tissue by immunogold electron microscopy using anti-AtACBP3 antibodies. AtACBP3pro::GUS was induced locally in Arabidopsis leaves upon wounding, and the expression of wound-responsive jasmonic acid marker genes (JASMONATE ZIM-DOMAIN10, VEGETATIVE STORAGE PROTEIN2, and LIPOXYGENASE2) increased more significantly in both locally wounded and systemic leaves of the wild type in comparison to acbp3 and AtACBP3-RNAi. Oxylipin-related fatty acid (FA) (C18:2-FA, C18:3-FA and methyl jasmonate) content was observed to be lower in acbp3 and AtACBP3-RNAi than wild-type phloem exudates using gas chromatography-mass spectrometry. Experiments using recombinant AtACBP3 in isothermal titration calorimetry analysis showed that medium- and long-chain acyl-CoA esters bind (His)6-AtACBP3 with KD values in the micromolar range. Taken together, these results suggest that AtACBP3 is likely to be a phloem-mobile protein that affects the FA pool and jasmonate content in the phloem, possibly by its binding to acyl-CoA esters.

10.
Phys Rev Lett ; 120(3): 030501, 2018 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-29400544

RESUMEN

We perform decoy-state quantum key distribution between a low-Earth-orbit satellite and multiple ground stations located in Xinglong, Nanshan, and Graz, which establish satellite-to-ground secure keys with ∼kHz rate per passage of the satellite Micius over a ground station. The satellite thus establishes a secure key between itself and, say, Xinglong, and another key between itself and, say, Graz. Then, upon request from the ground command, Micius acts as a trusted relay. It performs bitwise exclusive or operations between the two keys and relays the result to one of the ground stations. That way, a secret key is created between China and Europe at locations separated by 7600 km on Earth. These keys are then used for intercontinental quantum-secured communication. This was, on the one hand, the transmission of images in a one-time pad configuration from China to Austria as well as from Austria to China. Also, a video conference was performed between the Austrian Academy of Sciences and the Chinese Academy of Sciences, which also included a 280 km optical ground connection between Xinglong and Beijing. Our work clearly confirms the Micius satellite as a robust platform for quantum key distribution with different ground stations on Earth, and points towards an efficient solution for an ultralong-distance global quantum network.

11.
Oncogene ; 37(9): 1192-1204, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29238041

RESUMEN

Macrophages are a critical component in host immune responses against tumor. In this work we investigated the role of forkhead box O1 (FoxO1) in the transcriptional regulation in macrophages, which affects the anti-tumor functions of tumor-associated macrophages (TAMs). First, we showed that TAMs expressed reduced levels of FoxO1, which was associated with their protumoral M2 polarization state. The suppression of FoxO1 expression in TAM was induced by the hypoxic condition in the tumor microenviroment. Next, we confirmed that FoxO1 positively regulates MHC-II genes by binding to the promoter region of Ciita gene, the master activator of multiple MHC-II genes. Loss of FoxO1 in TAMs resulted in reduced MHC-II expression. Furthermore, we used FoxO1 conditional knockout mice to show that FoxO1 deficiency in myeloid cells exacerbates tumor growth. These results demonstrate that the protumoral property of TAMs is induced by the hypoxia-triggered FoxO1 deficiency, which could be a potential target of novel anti-tumor therapies.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Carcinoma Hepatocelular/patología , Proteína Forkhead Box O1/metabolismo , Proteína Forkhead Box O1/fisiología , Genes MHC Clase II , Macrófagos/patología , Melanoma/patología , Animales , Apoptosis , Biomarcadores de Tumor/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Proliferación Celular , Neoplasias del Colon/genética , Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , Proteína Forkhead Box O1/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Hipoxia/fisiopatología , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Macrófagos/metabolismo , Melanoma/genética , Melanoma/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Pronóstico , Regiones Promotoras Genéticas , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/metabolismo , Neoplasias Cutáneas/patología , Transactivadores/genética , Transactivadores/metabolismo , Células Tumorales Cultivadas
12.
Biol Pharm Bull ; 40(12): 2088-2095, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29199233

RESUMEN

This study aimed to investigate the effect of hematoporphyrin dimethylether (HDME)-mediated photodynamic therapy for laser-induced choroidal neovascularization (CNV) in adult Brown Norway rats. HDME was administered via tail vein at 14 d after the laser photocoagulation, and the rats received irradiance with a laser light at 570 nm at 15 min after injection. CNV was evaluated by fundus photography, fundus fluorescein angiography, optical coherence tomography, and hematoxylin and eosin staining. We found that CNV was occurred at 7 d after photocoagulation and reaching peak activity at 14 d after photocoagulation. There is a significant reduction in the total area of the fluorescein leakage and the number of strong fluorescein leakage spots on 7 d after HDME-mediated photodynamic therapy (PDT). The results suggest that HDME-mediated PDT inhibits laser-induced CNV in rats, representing a promising therapy for wet age-related macular degeneration.


Asunto(s)
Neovascularización Coroidal/tratamiento farmacológico , Hematoporfirinas/uso terapéutico , Éteres Metílicos/uso terapéutico , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/uso terapéutico , Animales , Permeabilidad Capilar , Neovascularización Coroidal/diagnóstico por imagen , Neovascularización Coroidal/etiología , Modelos Animales de Enfermedad , Angiografía con Fluoresceína , Fondo de Ojo , Hematoporfirinas/química , Humanos , Rayos Láser/efectos adversos , Masculino , Éteres Metílicos/química , Fármacos Fotosensibilizantes/química , Ratas , Ratas Endogámicas BN
13.
Nature ; 549(7670): 43-47, 2017 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-28825707

RESUMEN

Quantum key distribution (QKD) uses individual light quanta in quantum superposition states to guarantee unconditional communication security between distant parties. However, the distance over which QKD is achievable has been limited to a few hundred kilometres, owing to the channel loss that occurs when using optical fibres or terrestrial free space that exponentially reduces the photon transmission rate. Satellite-based QKD has the potential to help to establish a global-scale quantum network, owing to the negligible photon loss and decoherence experienced in empty space. Here we report the development and launch of a low-Earth-orbit satellite for implementing decoy-state QKD-a form of QKD that uses weak coherent pulses at high channel loss and is secure because photon-number-splitting eavesdropping can be detected. We achieve a kilohertz key rate from the satellite to the ground over a distance of up to 1,200 kilometres. This key rate is around 20 orders of magnitudes greater than that expected using an optical fibre of the same length. The establishment of a reliable and efficient space-to-ground link for quantum-state transmission paves the way to global-scale quantum networks.

14.
Biomed Pharmacother ; 92: 285-292, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28551549

RESUMEN

Photodynamic therapy (PDT) is emerging as a promising method for the treatment of various cancer diseases. However, the clinical application of PDT is limited due to the lack of effective photosensitizers. In this study, a novel chlorophyll derivative, N,N-bis(2-carboxyethyl)pyropheophorbide a (BPPA), had been synthesized and characterized. BPPA had a characteristic long wavelength absorption peak at 669nm and a singlet oxygen quantum yield of 0.54. To investigate the photodynamic ability of BPPA against cholangiocarcinoma (CCA), cellular uptake, subcellular location and bio-distribution, in vitro and in vivo PDT efficacy of BPPA were studied. The results showed that BPPA could rapidly accumulate in QBC-939 cells and localize in the cytoplasm. BPPA- PDT was effective in reducing the cell viability in a drug dose- and light dose-dependent manner in vitro. In CCA xenograft nude mouse model, the concentration of BPPA in the plasma lowered rapidly, and the fluorescence signal peaked at 0.5h and 2h after injection in the skin and tumor, respectively. Significant quantities could be observed in the tumor. BPPA followed by irradiation could significantly inhibit growth of tumors, and histological examination revealed necrotic damage in PDT-treated tumors. These results suggested that BPPA could be a promising drug candidate for photodynamic therapy in cholangiocarcinoma.


Asunto(s)
Neoplasias de los Conductos Biliares/tratamiento farmacológico , Clorofila/uso terapéutico , Colangiocarcinoma/tratamiento farmacológico , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/uso terapéutico , Animales , Neoplasias de los Conductos Biliares/patología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Clorofila/química , Clorofila/farmacología , Colangiocarcinoma/patología , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/farmacología , Distribución Aleatoria , Ensayos Antitumor por Modelo de Xenoinjerto/métodos
15.
Bioorg Chem ; 71: 299-304, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28267982

RESUMEN

A series of 2-morpholinetetraphenylporphyrins functionalized with various substituents (Cl, Me, MeO group) at 4-phenyl position were prepared via nucleophilic substitution of 2-nitroporphyrin copper derivatives with morpholine by refluxing under a nitrogen atmosphere and then demetalization. Their basic photophysical properties, intracellular localization, cytotoxicities in vitro and in vivo were also investigated. All synthesized photosensitizers exhibited longer maxima absorption wavelengths than Hematoporphyrin monomethyl ether (HMME). They showed low dark cytotoxicity compared with that of HMME and were more phototoxic than HMME against Eca-109 cells in vitro. M3 also exhibited better photodynamic antitumor efficacy on BALB/c nude mice at a lower concentration. Therefore, M3 is a promising antitumor photosensitizer in photodynamic therapy application.


Asunto(s)
Morfolinas/química , Morfolinas/uso terapéutico , Neoplasias/tratamiento farmacológico , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/uso terapéutico , Porfirinas/química , Porfirinas/uso terapéutico , Animales , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Femenino , Hematoporfirinas/farmacología , Humanos , Ratones Endogámicos BALB C , Ratones Desnudos , Morfolinas/síntesis química , Morfolinas/farmacología , Fotoquimioterapia , Fármacos Fotosensibilizantes/síntesis química , Fármacos Fotosensibilizantes/farmacología , Porfirinas/síntesis química , Porfirinas/farmacología
16.
J Photochem Photobiol B ; 165: 213-219, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27816643

RESUMEN

Photodynamic therapy (PDT) is a noninvasive therapeutic and promising procedure in cancer treatment and has attracted considerable attention in recent years. In the present paper, 2-piperidinetetraphenylporphyrin derivatives (P1-P3) conjugated with different substituents (Cl, Me, MeO group) at phenyl position were synthesized via nucleophilic substitution of 2-nitroporphyrin copper derivatives with piperidine by refluxing under a nitrogen atmosphere and then demetalization. The combination of 1H NMR, 13C NMR and HR-MS was used to elucidate the identities of them. Their photophysical and photochemical properties, intracellular localization, cytotoxicity in vitro and in vivo against QBC-939 cells were investigated. They have absorption at wavelength about 650nm. All synthesized photosensitizers showed low dark cytotoxicity and comparable with that of hematoporphyrin monomethyl ether (HMME). And they were more phototoxic than HMME to QBC-939 cells in vitro. In bearing QBC-939 tumor BALB/c nude mice, when it treated with 5mg/kg dose of PS and laser light (650nm, 100J/cm2, 180mW/cm2), the growth of tumor was inhibited compared to the control group. Among them, P3 exhibited better photodynamic antitumor efficacy on BALB/c nude mice at lower concentration. These results indicate that P3 is a new potential antitumor photosensitizer in photodynamic therapy and deserves further investigation.


Asunto(s)
Fotoquimioterapia , Fármacos Fotosensibilizantes/farmacología , Piperidinas/química , Porfirinas/farmacología , Animales , Línea Celular , Femenino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Fármacos Fotosensibilizantes/química , Porfirinas/química
17.
Plant Mol Biol ; 92(6): 717-730, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27645136

RESUMEN

Arabidopsis thaliana ACYL-COA-BINDING PROTEIN6 (AtACBP6) encodes a cytosolic 10-kDa AtACBP. It confers freezing tolerance in transgenic Arabidopsis, possibly by its interaction with lipids as indicated by the binding of acyl-CoA esters and phosphatidylcholine to recombinant AtACBP6. Herein, transgenic Arabidopsis transformed with an AtACBP6 promoter-driven ß-glucuronidase (GUS) construct exhibited strong GUS activity in the vascular tissues. Immunoelectron microscopy using anti-AtACBP6 antibodies showed AtACBP6 localization in the phloem especially in the companion cells and sieve elements. Also, the presence of gold grains in the plasmodesmata indicated its potential role in systemic trafficking. The AtACBP6 protein, but not its mRNA, was found in phloem exudate of wild-type Arabidopsis. Fatty acid profiling using gas chromatography-mass spectrometry revealed an increase in the jasmonic acid (JA) precursor, 12-oxo-cis,cis-10,15-phytodienoic acid (cis-OPDA), and a reduction in JA and/or its derivatives in acbp6 phloem exudates in comparison to the wild type. Quantitative real-time PCR showed down-regulation of COMATOSE (CTS) in acbp6 rosettes suggesting that AtACBP6 affects CTS function. AtACBP6 appeared to affect the content of JA and/or its derivatives in the sieve tubes, which is consistent with its role in pathogen-defense and in its wound-inducibility of AtACBP6pro::GUS. Taken together, our results suggest the involvement of AtACBP6 in JA-biosynthesis in Arabidopsis phloem tissues.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Proteínas Portadoras/metabolismo , Ciclopentanos/metabolismo , Oxilipinas/metabolismo , Floema/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas Portadoras/genética
18.
World J Surg Oncol ; 14(1): 10, 2016 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-26762567

RESUMEN

BACKGROUND: The invasion of colon cancer is associated with the tumor angiogenesis. Endostatin is an important anti-angiogenic agent, and the additive effect of endostatin with a chemotherapeutic agent, cyclophosphamide, on micrangium has not been established. METHODS: Male BALB/c strain nude mice were injected with human colorectal carcinoma cells (HCT-116). The mice were divided into four groups (n=15, each group) and were treated with different concentrations of endostatin (15, 10, and 5 mg/kg/day), cyclophosphamide (20, 10, and 5 mg/kg/day), and combination of endostatin/cyclophosphamide (15+20, 15+10, and 15+5 mg/kg/day). The tumor inhibition rate was evaluated, followed by the quantification of messenger ribonucleic acid (mRNA) and protein expression of notch signaling components NOTCH-1, NOTCH-3, NOTCH-4, JAG-1, DLL-4, Hes-1, and Hey-1 using quantitative polymerase chain reaction (qPCR). The protein expression of NOTCH-3, JAG-1, and DLL-4 was confirmed using western blotting. Microvessel density (MVD) was evaluated to detect micrangium following the treatment. RESULTS: The endostatin/cyclophosphamide-treated samples exhibited an additive effect on the tumor inhibition rate and the microvessel count. NOTCH-1, NOTCH-3, NOTCH-4, JAG-1, Hes-1, and Hey-1 expression levels were highly correlated and downregulated in the treated samples, whereas DLL-4 expression was upregulated that accounted for its anti-angiogenic property. CONCLUSIONS: The combination treatment of colon cancer with endostatin and a chemotherapeutic agent, cyclophosphamide proves to be an efficient therapeutic strategy to inhibit the rapid vasculature formation confirmed by the differential expression of notch signaling components.


Asunto(s)
Antineoplásicos/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Neoplasias del Colon/tratamiento farmacológico , Ciclofosfamida/farmacología , Endostatinas/farmacología , Microvasos/efectos de los fármacos , Neovascularización Patológica/tratamiento farmacológico , Animales , Antineoplásicos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biomarcadores de Tumor/metabolismo , Western Blotting , Línea Celular Tumoral , Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , Ciclofosfamida/uso terapéutico , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Endostatinas/uso terapéutico , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Reacción en Cadena de la Polimerasa , Distribución Aleatoria , Receptores Notch/metabolismo , Transducción de Señal/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
19.
Artículo en Inglés | MEDLINE | ID: mdl-24521497

RESUMEN

In this study, we sequenced the complete mitochondrial genome of Parazacco spilurus (Cypriniformes, Cyprinidae). This mitochondrial genome, consisting of 16,612 base pairs (bp), encoded 13 protein-coding genes, 2 ribosomal RNAs, 22 transfer RNAs, and a noncoding control region as those found in other vertebrates, with the gene synteny identical to that of typical vertebrates. Control region (D-Loop), of 926 bp in length, is located between tRNA(Pro) and tRNA(Phe). The overall base composition of the heavy strand shows T 26.91%, C 26.01%, A 30.45% and G 16.63%, with an AT bias of 57.36%.


Asunto(s)
Cyprinidae/genética , Genoma Mitocondrial/genética , Análisis de Secuencia de ADN , Animales , Genes de ARNr , Anotación de Secuencia Molecular , Datos de Secuencia Molecular , Sistemas de Lectura Abierta/genética , ARN de Transferencia/genética
20.
Appl Microbiol Biotechnol ; 99(3): 1485-97, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25261128

RESUMEN

This study investigated methanogenic communities involved in degradation of tetramethylammonium hydroxide (TMAH) in three full-scale bioreactors treating TMAH-containing wastewater. Based on the results of terminal-restriction fragment-length polymorphism (T-RFLP) and quantitative PCR analyses targeting the methyl-coenzyme M reductase alpha subunit (mcrA) genes retrieved from three bioreactors, Methanomethylovorans and Methanosarcina were the dominant methanogens involved in the methanogenic degradation of TMAH in the bioreactors. Furthermore, batch experiments were conducted to evaluate mcrA messenger RNA (mRNA) expression during methanogenic TMAH degradation, and the results indicated that a higher level of TMAH favored mcrA mRNA expression by Methansarcina, while Methanomethylovorans could only express considerable amount of mcrA mRNA at a lower level of TMAH. These results suggest that Methansarcina is responsible for methanogenic TMAH degradation at higher TMAH concentrations, while Methanomethylovorans may be important at a lower TMAH condition.


Asunto(s)
Bacterias/metabolismo , Reactores Biológicos/microbiología , Metano/metabolismo , Compuestos de Amonio Cuaternario/metabolismo , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Polimorfismo de Longitud del Fragmento de Restricción , Aguas del Alcantarillado/microbiología
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