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1.
Ann Oncol ; 29(2): 311-323, 2018 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-29216340

RESUMEN

Tissue biopsy is the standard diagnostic procedure for cancer. Biopsy may also provide material for genotyping, which can assist in the diagnosis and selection of targeted therapies but may fall short in cases of inadequate sampling, particularly from highly heterogeneous tumors. Traditional tissue biopsy suffers greater limitations in its prognostic capability over the course of disease, most obviously as an invasive procedure with potential complications, but also with respect to probable tumor clonal evolution and metastasis over time from initial biopsy evaluation. Recent work highlights circulating tumor DNA (ctDNA) present in the blood as a supplemental, or perhaps an alternative, source of DNA to identify the clinically relevant cancer mutational landscape. Indeed, this noninvasive approach may facilitate repeated monitoring of disease progression and treatment response, serving as a means to guide targeted therapies based on detected actionable mutations in patients with advanced or metastatic solid tumors. Notably, ctDNA is heralding a revolution in the range of genomic profiling and molecular mechanisms to be utilized in the battle against cancer. This review will discuss the biology of ctDNA, current methods of detection and potential applications of this information in tumor diagnosis, treatment, and disease prognosis. Conventional classification of tumors to describe cancer stage follow the TNM notation system, heavily weighting local tumor extent (T), lymph node invasion (N), and detectable metastasis (M). With recent advancements in genomics and bioinformatics, it is conceivable that routine analysis of ctDNA from liquid biopsy (B) may make cancer diagnosis, treatment, and prognosis more accurate for individual patients. We put forward the futuristic concept of TNMB tumor classification, opening a new horizon for precision medicine with the hope of creating better outcomes for cancer patients.


Asunto(s)
Biomarcadores de Tumor/sangre , ADN Tumoral Circulante/sangre , Biopsia Líquida/métodos , Estadificación de Neoplasias/métodos , Neoplasias/sangre , Humanos , Neoplasias/clasificación , Neoplasias/diagnóstico
2.
Int J Tuberc Lung Dis ; 16(12): 1674-9, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23131268

RESUMEN

OBJECTIVE: To determine whether the nucleic acid amplification (NAA) test on specimens collected by bronchoscopy improves the diagnostic accuracy of pulmonary tuberculosis (PTB) in sputum-negative patients. DESIGN: Bronchoscopy was performed among smear-negative PTB suspects to collect respiratory specimens to assess the efficacy and accuracy of the Amplified Mycobacterium Tuberculosis Direct (AMTD) test in the diagnosis of PTB. RESULTS: In 105 PTB suspects, 80 were finally excluded, of whom two were false-AMTD-positive. PTB (n = 25) was diagnosed in 10 patients culture-positive for Mycobacterium Tuberculosis (7/105 bronchial wash/bronchoalveolar lavage [BW/BAL] specimens, 6/315 expectorated sputum specimens [2 positive in 2 patients; 1 positive in 2 patients], and one with both), and in 15 patients with improvement after anti-tuberculosis treatment. Among the 25 PTB patients, 20 were AMTD-positive, of whom four were culture-positive. Three AMTD-negative patients were culture-positive. The sensitivity and specificity of AMTD were respectively 80.0% and 97.5%. The diagnostic yield was higher in respiratory specimens obtained at bronchoscopy and measured by AMTD than in conventional sputum or BW/BAL culture. CONCLUSION: NAA testing on specimens collected using bronchoscopy provides a highly efficient and reliable approach in the diagnosis of PTB in smear-negative PTB suspects.


Asunto(s)
Líquido del Lavado Bronquioalveolar/microbiología , Broncoscopía , ADN Bacteriano/aislamiento & purificación , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/aislamiento & purificación , Técnicas de Amplificación de Ácido Nucleico , Esputo/microbiología , Tuberculosis Pulmonar/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Distribución de Chi-Cuadrado , Reacciones Falso Positivas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Curva ROC , Juego de Reactivos para Diagnóstico , Sensibilidad y Especificidad , Tuberculosis Pulmonar/microbiología , Adulto Joven
3.
Oncogene ; 30(48): 4791-801, 2011 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-21625211

RESUMEN

14-3-3σ, a gene upregulated by p53 in response to DNA damage, exists as part of a positive-feedback loop, which activates p53 and is a human cancer epithelial marker downregulated in various cancer types. 14-3-3σ levels are critical for maintaining p53 activity in response to DNA damage and regulating signal mediators such as Akt. In this study, we identify mammalian constitutive photomorphogenic 1 (COP1) as a novel E3 ubiquitin ligase for targeting 14-3-3σ through proteasomal degradation. We show for the first time that COP9 signalosome subunit 6 (CSN6) associates with COP1 and is involved in 14-3-3σ ubiquitin-mediated degradation. Mechanistic studies show that CSN6 expression leads to stabilization of COP1 through reducing COP1 self-ubiquitination and decelerating COP1's turnover rate. We also show that CSN6-mediated 14-3-3σ ubiquitination is compromised when COP1 is knocked down. Thus, CSN6 mediates 14-3-3σ ubiquitination through enhancing COP1 stability. Subsequently, we show that CSN6 causes 14-3-3σ downregulation, thereby activating Akt and promoting cell survival. Also, CSN6 overexpression leads to increased cell growth, transformation and promotes tumorigenicity. Significantly, 14-3-3σ expression can correct the abnormalities mediated by CSN6 expression. These data suggest that the CSN6-COP1 axis is involved in 14-3-3σ degradation, and that deregulation of this axis will promote cell growth and tumorigenicity.


Asunto(s)
Proteínas 14-3-3/metabolismo , Biomarcadores de Tumor/metabolismo , Exonucleasas/metabolismo , Complejos Multiproteicos/fisiología , Péptido Hidrolasas/fisiología , Ubiquitina-Proteína Ligasas/metabolismo , Complejo del Señalosoma COP9 , Línea Celular , Exorribonucleasas , Citometría de Flujo , Humanos , Reacción en Cadena de la Polimerasa , Ubiquitinación
4.
Inflamm Res ; 56(5): 195-203, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17588135

RESUMEN

OBJECTIVE: The phagocytic recognition and clearance of the recruited inflammatory cells with prolonged survival play a pivotal role in relieving tissue inflammation and maintaining tissue homeostasis. Transgenic mice expressing Bcl-2 in mature neutrophils demonstrated that Bcl-2 attenuated neutrophil apoptosis, while the homeostasis of the neutrophil population was essentially unaffected. This result suggests that clearance of neutrophils with prolonged survival operates independently from apoptosis. Owing to the constitutive and inducible expression of Bcl-2 homologue, A1 in human neutrophils and the intolerance of preparation for the isolated human neutrophils with prolonged survival, the human promyelocytic HL60-A1 transfectants were established to study the mechanism of phagocytic recognition/clearance of the cells with prolonged survival. MATERIALS AND METHODS: The non-apoptotic cells with prolonged survival were enriched by serum withdrawal for five days and negatively isolated by annexin V-binding beads. Then, the cells were labeled with a fluorogenic marker. Monocyte-derived macrophages (MDM) were co-cultured to perform the phagocytosis assay, and flow cytometry was employed to determine the phagocytic index. RESULTS: In the serum-free condition, the phagocytic index of HL60-A1 transfectants was little different from that of the HL60-EGFP control, despite showing a significantly lower degree of apoptosis. While the phagocytic index of HL60-EGFP control was significantly correlated with the degree of apoptosis, the index of the HL60-A1 transfectants was less relevant to it. The phagocytic index for the annexin V-positive cells did not distinguish the two cell types. However, the phagocytic index for the annexin V-negative cells from the HL60-A1 transfectants was increased with age in days. Preincubation of MDM with the scavenger receptor inhibitor, Oxi-LDL, and the inhibitory antibodies against alphavbeta3, CD14 and CD36 surface molecules could attenuate the phagocytic recognition of the annexin V-positive HL60 cells but not the annexin V-negative A1 transfectants with prolonged survival. CONCLUSIONS: This study thus suggests that a mechanism unrelated to apoptosis exists, which mediates the phagocytic clearance of the non-apoptotic cells with prolonged survival and may be associated with A1 function in the myeloid cells.


Asunto(s)
Apoptosis/fisiología , Neutrófilos/patología , Fagocitosis/fisiología , Proteínas Proto-Oncogénicas c-bcl-2/genética , Apoptosis/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Células Cultivadas , Regulación de la Expresión Génica , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Células HL-60 , Humanos , Lipoproteínas LDL/farmacología , Macrófagos/metabolismo , Macrófagos/patología , Antígenos de Histocompatibilidad Menor , Neutrófilos/metabolismo , Fagocitosis/efectos de los fármacos , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Transfección
5.
Reprod Domest Anim ; 39(3): 146-53, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15182290

RESUMEN

The availability of cow ovaries from the slaughterhouse has been very limited in Taiwan. To maximize the use of cow ovaries for research purposes, whole ovary dissection was performed and the developmental competence of the oocytes derived from different sizes of follicles was assessed by the rates of in vitro maturation (IVM) and parthenogenetic activation of the oocytes in Experiment 1 (Exp 1). Cumulus-oocyte complexes (COCs) derived from small (1-2 mm) and large (3-8 mm) follicles were subjected to standard IVM culture for 24 h. Mature oocytes were selected and then parthenogenetically activated using A23187 (5 microm, 5 min) or thimerosal (200 microm, 10 min) alone or combined with 6-dimethylaminopurine (2.5 mm and 3.5 h, respectively). Activation rates of the oocytes, neither from the large nor small follicles, were affected by different activation treatments (single or combined stimuli). Whereas maturation rates for the oocytes from large follicles were superior to those from small follicles in both the single (59% vs 45%) and combined treatments (76% vs 40%; p < 0.05). To understand how prolonged heat shock (HS) influences cytoskeletal configurations of mature bovine oocytes, in Experiment 2 (Exp 2), matured oocytes derived from large follicles were randomly allocated to different durations of HS treatments at 41.5 degrees C for 0 (C0h, control, n = 12), 1 (HS1h, n = 28), 2 (HS2h, n = 31), and 4 h (HS4h, n = 30). An additional control group was cultured for 4 h without HS (38.5 degrees C, 4 h, n = 35). Alterations in nuclear structures, microtubules (MTs), and microfilaments (MFs) of the oocytes were examined. Abnormalities in the chromosomes, spindle MTs and the percentages of oocytes with cytoplasmic MTs increased with time of HS treatment. The intensity of the MF distribution in the HS oocytes was also altered. Significant changes in the cytoskeleton after HS may be associated with the reduced development under hyperthermia and, perhaps, with the low pregnancy rates of the animals during hot seasons.


Asunto(s)
Bovinos/fisiología , Citoesqueleto/fisiología , Respuesta al Choque Térmico/fisiología , Oocistos/fisiología , Folículo Ovárico/fisiología , Animales , Femenino
6.
Opt Lett ; 25(8): 524-6, 2000 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-18064099

RESUMEN

We demonstrate a method for spectrally shaping optical pulses that is readily reconfigurable and can produce variable filter functions. This practical technique relies on a compact and robust 3.86-m-long linearly chirped fiber Bragg grating that chromatically disperses the pulse to ~30 ns. We then shape the pulse envelope, and thus the pulse spectrum, with a programmable arbitrary waveform generator and an amplitude modulator to obtain several filter functions.

7.
Biol Cybern ; 76(4): 285-98, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9195745

RESUMEN

The goals of this research are: (1) to apply knowledge of human neuro-musculo-skeletal motion control to a biomechanically designed, neural controlled, 'anthroform' robotic arm system, (2) to demonstrate that such a system is capable of responses that match those of the human arm reasonably well in comparable experiments, and (3) to utilize the anthroform arm system to study some controversial issues and to predict new phenomena of the human motion control system. A physiologically analogous artificial neural network controller and an anatomically accurate robotic testing elbow are applied in this study. In order to build the physical elbow system to have mechanical properties as close as possible to the human arm, McKibben pneumatic artificial muscles, force sensors, and mechanical muscle spindles are integrated in the system with anatomically accurate muscle attachment points. A physiologically analogous, artificial neural network controller is used to emulate the behavior of spinal segmental reflex circuitry including Ia and Ib afferent feedbacks. Systematic experiments of elbow posture maintenance are performed and compared with physiological experimental data. New experiments are performed in which responses to torque perturbation are measured when selected afferent pathways are blocked. A 'covariance diagram' is introduced. And a linear model is used to help to analyze the roles of system components. The results show that muscle co-contraction and Ia afference with gamma dynamic motoneuron excitation are two efficient ways to increase joint stiffness and damping, which in turn reduces the mechanical sensitivity of the joint to external perturbation and shortens the settling time of the system.


Asunto(s)
Antebrazo/fisiología , Postura , Robótica , Vías Aferentes/fisiología , Fenómenos Biomecánicos , Humanos
8.
Cancer Chemother Pharmacol ; 30(4): 281-5, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1379522

RESUMEN

Neoadjuvant chemotherapy consisting of 2-3 courses of cisplatin, vincristine, and bleomycin was used in the primary treatment of 36 consecutive patients with locally advanced early-stage cervical carcinoma [International Federation of Gynecology and Obstetrics (FIGO) stages Ib or IIa; tumor size, greater than or equal to 4 cm]. The effectiveness of the preoperative chemotherapy was evaluated in the surgical specimens. Among the 33 evaluable patients, the overall clinical response rate was 84.8%, which included a complete response in 8 patients (24.2%) and a partial response in 20 subjects (60.6%). No residual tumor was found in the surgical specimens obtained from 2 complete responders. This therapy induced varying degrees of tumor shrinkage and rendered radical surgery feasible in all evaluable cases despite the initial bulky size of the lesions. No significant difference was observed in the response rate according to age and disease stage. Lymph-node metastases were found after chemotherapy in 18.2% (6/33) of the patients. Grade II and III hematological toxicities occurred in 23.3% of the 90 chemotherapy cycles completed. Nausea and vomiting occurred to a mild to moderate degree in 75 (83.3%) cycles. These preliminary results suggest that the administration of induction chemotherapy involving two to three courses of cisplatin, vincristine, and bleomycin prior to surgery is effective in reducing the tumor volume and in providing better circumstances for surgical removal of the early yet bulky cervical tumors and results in tolerable toxicity. This protocol is now undergoing prospective randomized trials to test its impact on long-term survival.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias del Cuello Uterino/tratamiento farmacológico , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Bleomicina/administración & dosificación , Cisplatino/administración & dosificación , Terapia Combinada , Esquema de Medicación , Estudios de Factibilidad , Femenino , Estudios de Seguimiento , Humanos , Ganglios Linfáticos/patología , Metástasis Linfática , Persona de Mediana Edad , Estadificación de Neoplasias , Proyectos Piloto , Neoplasias del Cuello Uterino/patología , Neoplasias del Cuello Uterino/cirugía , Vincristina/administración & dosificación
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