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1.
Ann Vasc Surg ; 93: 216-223, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36805427

RESUMEN

BACKGROUND: This retrospective study aimed to evaluate the safety and efficacy of cutting balloon angioplasty and conventional balloon angioplasty in supra-aortic arterial lesions caused by Takayasu arteritis. METHODS: A total of 46 patients with supra-aortic arterial lesions between January 2011 and December 2018 were included. Cutting balloon angioplasty was applied for 17 patients with 24 supra-aortic arterial lesions (group A), while 29 patients with 36 supra-aortic arterial lesions received conventional balloon angioplasty (group B). The preoperative clinical manifestation, operation result, and postoperative outcomes were recorded and compared in the 2 groups. RESULTS: Dizziness, visual disturbance, and unequal/absent pulses were the most common manifestations. The technical success of revascularization was 93.5% (43/46) in patients and 93.3% (56/60) in lesions. The stent implantation rate in group A was significantly lower than that in group B (4.2% vs. 50% in lesions, P < 0.05). Restenosis was the most common complication in both groups. Although the early (≤30 days) and late (>30 days) complications in group A were less than those in group B, there was no significant difference between the 2 groups (P > 0.05). Moreover, the primary-assisted patency of cutting balloon angioplasty and conventional balloon angioplasty at 1, 2, and 5 years were 66.7%, 62.5%, and 62.5% and 61.1%, 58.2%, and 49.8%, there was no significant difference between the 2 groups (P > 0.05), respectively. CONCLUSIONS: Compared with conventional balloon angioplasty, cutting balloon angioplasty could be considered a safe and effective alternative for supra-aortic arterial lesions caused by Takayasu arteritis, demonstrating better patency and clinical benefit.


Asunto(s)
Angioplastia de Balón , Arteritis de Takayasu , Humanos , Estudios Retrospectivos , Arteritis de Takayasu/complicaciones , Arteritis de Takayasu/diagnóstico por imagen , Arteritis de Takayasu/terapia , Resultado del Tratamiento , Stents , Angioplastia , Angioplastia de Balón/efectos adversos
2.
Biochem Biophys Res Commun ; 523(1): 220-225, 2020 02 26.
Artículo en Inglés | MEDLINE | ID: mdl-31848048

RESUMEN

Pentatricopeptide repeat (PPR) proteins are one of the largest protein families in land plants. PPR proteins exhibit sequence-specific RNA-binding activity and are implicated in plant growth and development related processes. In this study, we report that the radicleless 1 (rl1) mutant in rice (Oryza sativa L.) exhibited defective radicle emergence in embryos and compromised grain filling in endosperms. Gene cloning and confirmation via genetic complementation analyses showed that RL1 encodes a P-type PPR protein, which is localized to mitochondria. The RL1 protein was specifically involved in the splicing of intron 1 of the mitochondrial nad4 transcript, which encodes a subunit of the mitochondrial NADH dehydrogenase complex. Consistent with this observation, the rl1 mutant exhibited altered mitochondrial morphology and lower ATP accumulation compared with the wild type. Thus, our findings suggest that RL1-mediated nad4 splicing is crucial for embryo and endosperm development in rice.


Asunto(s)
Endospermo/crecimiento & desarrollo , Intrones/genética , Oryza/crecimiento & desarrollo , Oryza/genética , Proteínas de Plantas/genética , Empalme del ARN/genética , ARN de Planta/genética , Endospermo/genética , Regulación de la Expresión Génica de las Plantas/genética , Oryza/embriología
4.
Opt Express ; 24(11): 11950-60, 2016 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-27410117

RESUMEN

In this paper, we propose the idea of dynamic beam waist adjustment for laser inter-satellite communications, and study the performance of this dynamic-beam scheme. The beam waist adjustment is based on continuous detection of the instantaneous pointing error angle, which is performed at the transmitter side. Using a square to approximate the circular detector region, we obtain a closed-form expression for calculating the proportion of power that can be collected by the receiver aperture, and derive a simple algebraic solution for the optimum dynamic beam waist. Due to its simple form, the dynamic beam waist value can be computed in real time at the transmitter, and therefore, the adjustment is practically implementable. It is shown that the performance of laser inter-satellite links with dynamic beam waist is better than that with fixed beam waist.

5.
Opt Express ; 23(18): 23710-25, 2015 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-26368467

RESUMEN

Perceptual quality measurement of three-dimensional (3D) visual signals has become a fundamental challenge in 3D imaging fields. This paper proposes a novel no-reference (NR) 3D visual quality measurement (VQM) metric that uses simulations of the primary visual cortex (V1) of binocular vision. As the major technical contribution of this study, perceptual properties of simple and complex cells are considered for NR 3D-VQM. More specifically, the metric simulates the receptive fields of simple cells (one class of V1 neurons) using Gaussian derivative functions, and the receptive fields of complex cells (the other class of V1 neurons) using disparity energy responses and binocular rivalry responses. Subsequently, various quality-aware features are extracted from the primary visual cortex; these will change in the presence of distortions. Finally, those features are mapped to the subjective quality score of the distorted 3D visual signal by using support vector regression (SVR). Experiments on two publicly available 3D databases confirm the effectiveness of our proposed metric, compared to the relevant full-reference (FR) and NR metrics.

6.
Pharm Biol ; 53(7): 1016-21, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25471124

RESUMEN

CONTEXT: Overexpression of SIRT1 is considered to enhance the resistance of HepG2 cells to irradiation. Shikonin, a naturally occurring naphthoquinone compound, displays anticancer effects and circumvents cancer drug resistance. OBJECTIVES: This study investigated the MDR reversal effect of shikonin induced by the overexpression of SIRT1. MATERIALS AND METHODS: The overexpression of SIRT1 in HepG2 cells was established by lentivirus infection. Five days after transduction, real-time quantitative polymerase chain reaction and western blotting were used to detect the expression of SIRT1 and MDR1/P-gp. Drug resistance was also evaluated by flow cytometry after rhodamine-123 staining. On day 5, the multidrug resistance cells were treated by shikonin (10(-7), 10(-6), and 10(-5) µmol/L) one time. The cell viability was detected by the MTT assay, and apoptosis was evaluated by Hoechst 33342 staining and caspase-3 activity 24 h after shikonin treatment. RESULTS: Overexpression of SIRT1 decreased rhodamine-123 staining and successfully produced the R-HepG2 cell line. Compared with HepG2, the expression of MDR1/P-gp mRNA (3.45 ± 0.35) and protein (1.40 ± 0.05) were both upregulated in R-HepG2. Shikonin inhibited cell viability (from 93.9 ± 2.1 to 66.7 ± 1.5%), induced apoptosis of R-HepG2 (apoptotic ratio from 3.5 ± 0.8 to 47.5 ± 2.7%, caspase-3 activity from 103.5 ± 1.9 to 329.2 ± 14.9%, respectively), downregulated the mRNA and protein expression of SIRT1 and MDR1/P-gp, and decreased rhodamin 123 efflux. DISCUSSION AND CONCLUSION: In the present study, we demonstrated that shikonin is able to overcome drug resistance in hepatocellular carcinoma cells, and the mechanism is related to the SIRT1-MDR1/P-gp signaling pathway.


Asunto(s)
Resistencia a Múltiples Medicamentos/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Naftoquinonas/farmacología , Sirtuina 1/fisiología , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Resistencia a Múltiples Medicamentos/fisiología , Resistencia a Antineoplásicos/fisiología , Células Hep G2 , Humanos
7.
Comput Biol Chem ; 103: 107825, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36773520

RESUMEN

Regarding the importance of N-degron pathway in protein degradation network, the adaptor protein ClpS recognizes the substrates bearing classical N-degrons, and delivers them to caseinolytic protease complex ClpAP for degradation. Interestingly, the majority of N-degrons located near the N-terminus of protein substrate are belonged to the hydrophobic type amino acids. Chloroplast, an important organelle for plant photosynthesis, contain a diversified Clp degradation system. Despite several studies have confirmed that chloroplastic ClpS is able to interact with classical N-degrons derived from prokaryotes, whereas, the molecular mechanism underlying how the chloroplastic ClpS protein could recognize the substrate tagged by N-degrons is still unclear until now. Chlamydomonas reinhardtii is a kind of unicellular model organism for photosynthesis researches, which possesses a large cup-shaped chloroplast, and the corresponding genome data indicates that it owns bacterial homologous adaptor protein, named CrClpS1. However, the relevant biochemical knowledges, and protein structure researches for CrClpS1 adaptor aren't reported up to date. The molecular interactions between CrClpS1 and possible N-degrons are undefined as well. Here, we build a reliable homology model of CrClpS1 and find a hydrophobic pocket for N-degron binding. We combine molecular docking, molecular dynamic simulations, and MM/PBSA, MM/GBSA binding free energy estimations to elucidate the molecular properties of CrClpS1-N-degron interactions. Besides, we investigate the conformational changes for CrClpS1-apo in water-solvent environment and analyze its possible biological significances through a long time molecular dynamic simulation. Specifically, the adaptor CrClpS1 displays the stronger interactions with Phe, Trp, Tyr, His and Ile with respect to other amino acids. Using the residue decomposition analysis, the interactions between CrClpS1 and N-degrons are heavily depended on several conservative residues, which are located around the hydrophobic pocket, implying that chloroplast isolated from Chlamydomonas reinhadtii adopts a relatively conservative N-degron recognition mode. Besides, the opening-closure of hydrophobic pocket of CrClpS1 might be beneficial for the N-degron selectivity.


Asunto(s)
Chlamydomonas reinhardtii , Simulación del Acoplamiento Molecular , Chlamydomonas reinhardtii/metabolismo , Unión Proteica , Cloroplastos , Aminoácidos/metabolismo , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteolisis , Proteínas Bacterianas/metabolismo , Especificidad por Sustrato
8.
J Oral Maxillofac Surg ; 70(10): 2466-79, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22285335

RESUMEN

PURPOSE: To increase the understanding of head and neck Castleman disease (CD) and to improve its diagnosis and management. PATIENTS AND METHODS: A retrospective study was performed on the medical records of 14 patients with cervical CD treated at the Sun Yat-sen University Cancer Center from January 2000 through December 2009. The predictor variables were age, gender, site, size, and treatment modality. The outcome variables were survival time and recurrence. RESULTS: Neck level II (9/14) was the most common site for CD. On computed tomogram, all 14 cases appeared as nodular and cylindrical-shaped lesions growing along the neck. Computed tomogram showed a uniform density and clear margins of the lesions. Thirteen cases with hyaline-vascular type CD showed significant enhancement on enhancing computed tomographic scans. One case with plasma-cell type CD accompanied by Hodgkin lymphoma showed mild heterogeneous enhancement and a strong vascular shadow inside the lesion. Thirteen patients with unicentric CD underwent regional resection. Follow-up time ranged from 14 to 132 months, during which none of the patients relapsed. CONCLUSIONS: The results of this study suggest that head and neck CD has a low incidence and that the most common site is unilateral level II. Regional resection was the first choice for the treatment of unicentric CD. Overall, chemotherapy was associated with a poor prognosis in patients with multicentric CD. Future studies will focus on the early diagnosis and treatment of multicentric CD. Long-term follow-up is also necessary.


Asunto(s)
Enfermedad de Castleman/diagnóstico , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Enfermedad de Castleman/cirugía , Quimioterapia Adyuvante , Medios de Contraste , Femenino , Estudios de Seguimiento , Cabeza/patología , Humanos , Hialina , Cadenas kappa de Inmunoglobulina/análisis , Cadenas lambda de Inmunoglobulina/análisis , Factores Inmunológicos/análisis , Yohexol/análogos & derivados , Antígeno Ki-1/análisis , Masculino , Persona de Mediana Edad , Cuello/patología , Disección del Cuello , Células Plasmáticas/patología , Intensificación de Imagen Radiográfica/métodos , Receptores de Complemento 3d/análisis , Recurrencia , Estudios Retrospectivos , Tasa de Supervivencia , Tomografía Computarizada Espiral/métodos , Resultado del Tratamiento , Adulto Joven
9.
Annu Rev Plant Biol ; 73: 255-291, 2022 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-35226815

RESUMEN

The persistent triploid endosperms of cereal crops are the most important source of human food and animal feed. The development of cereal endosperms progresses through coenocytic nuclear division, cellularization, aleurone and starchy endosperm differentiation, and storage product accumulation. In the past few decades, the cell biological processes involved in endosperm formation in most cereals have been described. Molecular genetic studies performed in recent years led to the identification of the genes underlying endosperm differentiation, regulatory network governing storage product accumulation, and epigenetic mechanism underlying imprinted gene expression. In this article, we outline recent progress in this area and propose hypothetical models to illustrate machineries that control aleurone and starchy endosperm differentiation, sugar loading, and storage product accumulations. A future challenge in this area is to decipher the molecular mechanisms underlying coenocytic nuclear division, endosperm cellularization, and programmed cell death.


Asunto(s)
Grano Comestible , Endospermo , Diferenciación Celular , Grano Comestible/genética , Grano Comestible/metabolismo , Endospermo/genética , Endospermo/metabolismo , Regulación de la Expresión Génica de las Plantas , Almidón/metabolismo
10.
Materials (Basel) ; 15(16)2022 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-36013618

RESUMEN

Powder metallurgy (PM) has been widely used to produce various steels in industry, mainly due to its capabilities for manufacturing nearly net-shaped products and mass production. To improve the performances of PM stainless steels, the roles of 0.6 wt% B additive in the microstructures, mechanical properties, and corrosion resistances of PM 304L austenitic, 410L ferritic, and 410 martensitic stainless steels were investigated. The results showed that adding 0.6 wt% B significantly improved the sintered densities of the three kinds of stainless steels due to the liquid phase sintering (LPS) phenomenon. The borides in 304L + 0.6B, 410L + 0.6B, and 410 + 0.6B were rich in B and Cr atoms but deficient in Fe, Ni, or C atoms, as analyzed by electron probe micro-analysis. Furthermore, the B additive contributed to the improved apparent hardness and corrosion resistance of PM stainless steels. In the 410L stainless steel, the 0.6 wt% B addition increased the corrosion voltage from -0.43 VSCE to -0.24 VSCE and reduced the corrosion current density from 2.27 × 10-6 A/cm2 to 1.93 × 10-7 A/cm2. The effects of several factors, namely: porosity; the generation of boride; the matrix/boride interfacial areas; Cr depletion; and the microstructure on the corrosion performances are discussed. The findings clearly indicate that porosity plays a predominant role in the corrosion resistances of PM austenitic, ferritic, and martensitic stainless steels.

11.
Materials (Basel) ; 14(21)2021 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-34772059

RESUMEN

Powder metallurgy (PM) is a versatile process to manufacture nearly net-shaped metallic materials in industry. In this study, the PM process was used to fabricate two Fe-based laminated metal composites (LMCs), Fe-4Ni-3Cr-0.5Mo-0.5C/Fe and 410/304L. The results showed that after sintering, the LMCs were free of interfacial cracks and distortion, indicating that the PM process is a feasible means for producing these LMCs. In the Fe-4Ni-3Cr-0.5Mo-0.5C/Fe LMC, the diffusion of C resulted in the generation of a continuous pearlite layer between the Fe-4Ni-3Cr-0.5Mo-0.5C and Fe layers and a ferrite/pearlite mixture in the Fe layer. In the 410/304L LMC, the difference in the chemical potentials of C between the 304L and 410 layers led to the uphill diffusion of C from the 410 layer to the 304L layer. A continuous ferrite layer was thus formed near the interface of the 410 layer. Furthermore, a martensite layer of about 50 µm thickness was generated at the interface due to the high Cr and Ni content.

12.
Materials (Basel) ; 14(22)2021 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-34832447

RESUMEN

In this study, the wear behavior of a heat-treatable Al-7Si-0.5Mg-0.5Cu alloy fabricated by selective laser melting was investigated systematically. Compared with the commercial homogenized AA2024 alloy, the fine secondary phase of the SLM Al-Cu-Mg-Si alloy leads to a low specific wear rate (1.8 ± 0.11 × 10-4 mm3(Nm)-1) and a low average coefficient of friction (0.40 ± 0.01). After the T6 heat treatment, the SLM Al-Cu-Mg-Si alloy exhibits a lower specific wear rate (1.48 ± 0.02 × 10-4 mm3(Nm)-1), but a similar average coefficient of friction (0.34 ± 0.01) as the heat-treated AA2024 alloy. Altogether, the SLM Al-3.5Cu-1.5Mg-1Si alloy is suitable for the achievement of not only superior mechanical performance, but also improved tribological properties.

13.
Electrophoresis ; 31(11): 1862-72, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20506420

RESUMEN

For therapeutic antibody production Protein A chromatography is often replaced by non-affinity-based purification sequences, which are considered as more economical. 2-D DIGE was applied for evaluation of scale-up of non-affinity based process of a humanized monoclonal antibody, anti-Rh(D) IgG(1), in comparison with other conventional analytical methods, like SDS-PAGE, Western blot, or SEC. Due to a high sensitivity of this technique (125 pg protein/spot) and high dynamic range of five orders of magnitude, low molecular weight impurities were detected in purified samples. Cation exchange chromatography was efficient capture step for IgG(1) purification in laboratory and pilot scale. The differences between samples after first purification step in laboratory and pilot scale were compensated with second purification step where almost the same protein pattern was observed. 2-D DIGE is a helpful tool for monitoring of purification effects and for scale-up verification of downstream processes.


Asunto(s)
Anticuerpos Monoclonales/aislamiento & purificación , Electroforesis en Gel Bidimensional/métodos , Proteínas Recombinantes/aislamiento & purificación , Animales , Anticuerpos Monoclonales/inmunología , Western Blotting/métodos , Células CHO , Cromatografía en Gel/métodos , Cromatografía por Intercambio Iónico , Cricetinae , Cricetulus , Electroforesis en Gel de Poliacrilamida/métodos , Fluorescencia , Colorantes Fluorescentes , Humanos , Inmunoglobulina G/inmunología , Inmunoglobulina G/aislamiento & purificación , Proyectos Piloto , Proteínas Recombinantes/inmunología , Reproducibilidad de los Resultados , Sistema del Grupo Sanguíneo Rh-Hr/inmunología , Espectrometría de Fluorescencia
14.
Appl Opt ; 48(36): 6940-5, 2009 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-20029596

RESUMEN

Although barcodes can be used to manage data conveniently, they cannot be applied to small areas. Therefore, pointcodes are used to overcome the issue in this article. A pointcode uses a pointcode pattern to encode data and uses a pointcode image to decode data. A pointcode pattern is composed of many grating dots with different specified grating pitches and grating orientations. Moreover, there are two grating-dot sizes generated. When a laser beam illuminates a pointcode pattern with correct illuminating conditions, a pointcode image corresponding to the hidden data is diffractively reconstructed. A pointcode image is composed of many bright points with different positions. There are two possible bright-point sizes generated. A bright point or two bright points at specified positions are used to denote a number. Small pointcode patterns are enough to diffractively form pointcode images.

15.
IEEE Trans Image Process ; 27(5): 2086-2095, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29432092

RESUMEN

The blind quality evaluation of screen content images (SCIs) and natural scene images (NSIs) has become an important, yet very challenging issue. In this paper, we present an effective blind quality evaluation technique for SCIs and NSIs based on a dictionary of learned local and global quality features. First, a local dictionary is constructed using local normalized image patches and conventional -means clustering. With this local dictionary, the learned local quality features can be obtained using a locality-constrained linear coding with max pooling. To extract the learned global quality features, the histogram representations of binary patterns are concatenated to form a global dictionary. The collaborative representation algorithm is used to efficiently code the learned global quality features of the distorted images using this dictionary. Finally, kernel-based support vector regression is used to integrate these features into an overall quality score. Extensive experiments involving the proposed evaluation technique demonstrate that in comparison with most relevant metrics, the proposed blind metric yields significantly higher consistency in line with subjective fidelity ratings.

16.
Exp Hematol ; 34(9): 1249-61, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16939818

RESUMEN

OBJECTIVE: Clock genes are known to mediate circadian rhythms in the central nervous system and peripheral organs. Although they are expressed in mouse hematopoietic progenitor and stem cells, it is unknown if they are related to circadian rhythms in these cells. We therefore investigated the 24-hour patterns in the activity of several clock genes in the bone marrow (BM) side population (SP) primitive stem cells, and compared these 24-hour patterns to clock gene variations in the whole BM and liver. METHODS: Cells were obtained from 84 B6D2F(1) mice in three replicate experiments on the second day after release into constant darkness from a standardizing light-dark schedule. mRNA expression of clock genes was measured with quantitative reverse transcriptase polymerase chain reaction. RESULTS: mPer2 displayed circadian rhythms in SP cells, whole BM, and liver cells. mPer1 and mRev-erb alpha showed a circadian rhythm in whole BM and liver, but not SP cells. mBmal1 was not expressed rhythmically in SP cells, nor in the whole BM, contrary to rhythms observed in the liver. CONCLUSIONS: With the exception of mPer2, most clock genes studied in primitive hematopoietic SP stem cells were not oscillating in a fully organized circadian manner, which is similar to immature cells in rapidly proliferating organs, such as the testis and thymus. These findings indicate that circadian clock gene expression variations in BM are developmentally regulated.


Asunto(s)
Relojes Biológicos/fisiología , Ritmo Circadiano/fisiología , Regulación de la Expresión Génica/fisiología , Células Madre Hematopoyéticas/fisiología , Proteínas Nucleares/biosíntesis , Factores de Transcripción/biosíntesis , Animales , Proteínas de Ciclo Celular , Femenino , Perfilación de la Expresión Génica/métodos , Células Madre Hematopoyéticas/citología , Masculino , Ratones , Proteínas Nucleares/genética , Especificidad de Órganos/fisiología , Proteínas Circadianas Period , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Factores de Transcripción/genética
17.
Cancer Res ; 64(21): 7879-85, 2004 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-15520194

RESUMEN

Frequent transmeridian flights or predominant work at night can increase cancer risk. Altered circadian rhythms also predict for poor survival in cancer patients, whereas physical destruction of the suprachiasmatic nuclei (SCN), the hypothalamic circadian pacemaker, accelerates tumor growth in mice. Here we tested the effect of functional disruption of circadian system on tumor progression in a novel experimental model of chronic jet lag. B6D2F(1) mice were synchronized with 12 hours of light and 12 hours of darkness or underwent repeat 8-hour advances of the light/dark cycle every 2 days before inoculation of Glasgow osteosarcoma. The 24-hour changes were assessed for plasma corticosterone, clock protein mPER1 expression in the SCN, and mRNA expression of clock genes mPer2 and mRev-erbalpha in liver and tumor. Time series were analyzed by spectral analysis and/or Cosinor. Differences were compared with analysis of variance (ANOVA). The 24-hour rest/activity cycle was ablated, and the rhythms of body temperature, serum corticosterone, and mPER1 protein expression in the SCN were markedly altered in jet-lagged mice as compared with controls (ANOVA, P < 0.001 for corticosterone and P = 0.01 for mPER1). Tumor grew faster in the jet-lagged animals as compared with controls (ANOVA, P < 0.001), whereas exposure to constant light or darkness had no effect (ANOVA, P = 0.66 and P = 0.8, respectively). The expression of mPer2 and mRev-erbalpha mRNAs in controls showed significant circadian rhythms in the liver (P = 0.006 and P = 0.003, respectively, Cosinor) and in the tumor (P = 0.04 and P < 0.001). Both rhythms were suppressed in the liver (P = 0.2 and P = 0.1, respectively, Cosinor) and in the tumor (P = 0.5) of jet-lagged mice. Altered environmental conditions can disrupt circadian clock molecular coordination in peripheral organs including tumors and play a significant role in malignant progression.


Asunto(s)
Síndrome Jet Lag/complicaciones , Neoplasias/patología , Animales , Enfermedad Crónica , Ritmo Circadiano , Progresión de la Enfermedad , Expresión Génica , Masculino , Ratones , Núcleo Supraquiasmático/fisiología
18.
Chronobiol Int ; 22(4): 741-54, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16147904

RESUMEN

Dihydropyrimidine dehydrogenase (DPD) is a rate-limiting enzyme of 5-fluorouracil (5-FU) catabolism. Glutathione (GSH) is a tripeptide involved in platinum complex detoxification. This study explored the circadian rhythms of DPD activity and GSH concentration in the peripheral blood of 16 patients with histologically proven nasopharyngeal carcinoma (NPC) in order to guide the establishment of chronotherapeutic schedules for this cancer. DPD activity and GSH concentration were determined by high performance liquid chromatography (HPLC). Both variables displayed significant circadian rhythms (Cosinor analysis: p = 0.009 and 0.012, respectively). Peak DPD activity occurred at about 02:30 h; whereas, peak GSH concentration occurred around 12:40 h. The differences between the peak and nadir mean values were 25.5% and 38.7%, respectively. The study showed that the circadian rhythms in DPD activity and GSH concentration in Chinese NPC are similar to those reported for western patients with colorectal cancer, despite the differences in race and kinds of cancer. These findings imply that the chronotherapeutic schedule of 5-FU and platinum used to treat European colorectal cancer patients probably is applicable to Chinese NPC patients.


Asunto(s)
Carcinoma/sangre , Ritmo Circadiano , Dihidrouracilo Deshidrogenasa (NADP)/sangre , Glutatión/sangre , Neoplasias Nasofaríngeas/sangre , Adulto , Anciano , Carcinoma/enzimología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Nasofaríngeas/enzimología
19.
Chin Med J (Engl) ; 125(24): 4338-43, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23253698

RESUMEN

BACKGROUND: Treatment for malignant glioma generally consists of cytoreductive surgery followed by radiotherapy and chemotherapy. In this study, we intended to investigate the effects of 2-propylpentanoic acid (VPA), a histone deacetylase inhibitor, on chemosensitivity and radiosensitivity in human glioma cell lines. METHODS: Human glioma cell lines, T98-G, and SF295, were treated with temozolomide (TMZ) or irradiation (IR), with or without VPA (1.0 mmol/L). Then, cytotoxicity and clonogenic survival assay was performed. Cell cycle stage, apoptosis, and autophagy were also detected using flow cytometry and dansyl monocadaverin (MDC) incorporation assay. One-way analysis of variance (ANOVA) and t-test were used to analyze the differences among variant groups. RESULTS: Mild cytotoxicity of VPA was revealed in both cell lines, T98-G and SF295, with the 50% inhibiting concentration (IC50) value of (3.85 ± 0.58) mmol/L and (2.15 ± 0.38) mmol/L, respectively; while the IC50 value of TMZ was (0.20 ± 0.09) mmol/L for T98-G and (0.08 ± 0.02) mmol/L for SF295. Moreover, if combined with VPA (1.0 mmol/L) for 96 hours, the sensitivity of glioma cells to TMZ was significant increased (P < 0.05). The surviving fractions at 2 Gy (SF2) of T98-G and SF295 cells exposed to IR alone were 0.52 and 0.58. However, when VPA was combined with IR, the SF2 of T98-G and SF295 dropped to 0.39 (P = 0.047) and 0.49 (P = 0.049), respectively. Treatment with VPA plus TMZ or IR also resulted in a significant decrease in the proportion of cells in the G2 phase and increased apoptotic rates as well as autophagy in T98-G and SF295 cell lines (P < 0.01). CONCLUSION: VPA may enhance the activities of TMZ and IR on glioma cells possibly through cell cycle block and promote autophagy, and thus could be a potential sensitizer of glioma treatment.


Asunto(s)
Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/efectos de la radiación , Inhibidores de Histona Desacetilasas/farmacología , Ácido Valproico/farmacología , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Western Blotting , Línea Celular Tumoral , Dacarbazina/análogos & derivados , Dacarbazina/farmacología , Citometría de Flujo , Glioma/metabolismo , Humanos , Temozolomida
20.
Med Oncol ; 28 Suppl 1: S360-6, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21069476

RESUMEN

COX-2 induces the proliferation and invasion of oral squamous cell carcinoma. In the present study, the role of the COX-2 gene in the tongue cancer cell proliferation and invasion was investigated. A short hairpin RNA (shRNA)method was used to knock down COX-2 gene expression and investigate the relationship between COX-2 and VEGF-C, and the role of the COX-2 gene for proliferation and invasion was also investigated in the tongue cancer cell Tca8113. COX-2 gene overexpressed in tongue cancer cell line. Suppressing the expression of COX-2 by shRNA could decrease cell proliferation comparing with control shRNA. Nevertheless, depressing COX-2 gene expression by shRNA reduced VEGF-C expression on both mRNA and protein levels. VEGF-C gene expression could be regulated by COX-2 gene. Our results suggested that COX-2 played essential roles in the proliferation and metastasis of tongue cancer, and COX-2 could serve as a potential chemotherapy target for tongue cancer.


Asunto(s)
Proliferación Celular , Ciclooxigenasa 2/metabolismo , Transducción de Señal , Neoplasias de la Lengua/metabolismo , Factor C de Crecimiento Endotelial Vascular/metabolismo , Línea Celular Tumoral , Humanos , Invasividad Neoplásica , Neoplasias de la Lengua/patología
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