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Efficiently fabricating a cavity that can achieve strong interactions between terahertz waves and matter would allow researchers to exploit the intrinsic properties due to the long wavelength in the terahertz waveband. Here we show a terahertz detector embedded in a Tamm cavity with a record Q value of 1017 and a bandwidth of only 469 MHz for direct detection. The Tamm-cavity detector is formed by embedding a substrate with an Nb5N6 microbolometer detector between an Si/air distributed Bragg reflector (DBR) and a metal reflector. The resonant frequency can be controlled by adjusting the thickness of the substrate layer. The detector and DBR are fabricated separately, and a large pixel-array detector can be realized by a very simple assembly process. This versatile cavity structure can be used as a platform for preparing high-performance terahertz devices and opening up the study of the strong interactions between terahertz waves and matter.
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Classical and quantum space-to-ground communications necessitate highly sensitive receivers capable of extracting information from modulated photons to extend the communication distance from near-earth orbits to deep space explorations. To achieve gigabit data rates while mitigating strong background noise photons and beam drift in a highly attenuated free-space channel, a comprehensive design of a multi-functional detector is indispensable. In this study, we present an innovative compact multi-pixel superconducting nanowire single-photon detector array that integrates near-unity detection efficiency (91.6%), high photon counting rate (1.61 Gcps), large dynamic range for resolving different photon numbers (1-24), and four-quadrant position sensing function all within one device. Furthermore, we have constructed a communication testbed to validate the advantages offered by such an architecture. Through 8-PPM (pulse position modulation) format communication experiments, we have achieved an impressive maximum data rate of 1.5 Gbps, demonstrating sensitivities surpassing previous benchmarks at respective speeds. By incorporating photon number information into error correction codes, the receiver can tolerate maximum background noise levels equivalent to 0.8 photons/slot at a data rate of 120 Mbps-showcasing a great potential for daylight operation scenarios. Additionally, preliminary beam tracking tests were conducted through open-loop scanning techniques, which revealed clear quantitative dependence indicating sensitivity variations based on beam location. Based on the device characterizations and communication results, we anticipate that this device architecture, along with its corresponding signal processing and coding techniques, will be applicable in future space-to-ground communication tasks.
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Scaling up superconducting nanowire single-photon detectors (SNSPDs) into a large array for imaging applications is the current pursuit. Although various readout architectures have been proposed, they cannot resolve multiple-photon detections (MPDs) currently, which limits the operation of the SNSPD arrays at high photon flux. In this study, we focused on the readout ambiguity of a superconducting nanowire single-photon imager applying time-of-flight multiplexing readout. The results showed that image distortion depended on both the incident photon flux and the imaging object. By extracting multiple-photon detections on idle pixels, which were virtual because of the incorrect mapping from the ambiguous readout, a correction method was proposed. An improvement factor of 1.3~9.3 at a photon flux of µ = 5 photon/pulse was obtained, which indicated that joint development of the pixel design and restoration algorithm could compensate for the readout ambiguity and increase the dynamic range.
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We propose a simulation method for a multireflector terahertz imaging system. The description and verification of the method are based on an existing active bifocal terahertz imaging system at 0.22 THz. Using the phase conversion factor and angular spectrum propagation, the computation of the incident and received fields requires only a simple matrix operation. The phase angle is used to calculate the ray tracking direction, and the total optical path is used to calculate the scattering field of defective foams. Compared with the measurements and simulations of aluminum disks and defective foams, the validity of the simulation method is confirmed in the field of view of 50â cm × 90â cm at 8 m. This work aims to develop better imaging systems by predicting their imaging behavior for different targets before manufacturing.
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OBJECTIVE: Acute myeloid leukemia (AML) is a highly heterogeneous and recurrent hematological malignancy. Despite the emergence of novel chemotherapy drugs, AML patients' complete remission (CR) remains unsatisfactory. Consequently, it is imperative to discover new therapeutic targets or medications to treat AML. Such epigenetic changes like DNA methylation and histone modification play vital roles in AML. Peptidylarginine deminase (PAD) is a protein family of histone demethylases, among which the PAD2 and PAD4 expression have been demonstrated to be elevated in AML patients, thus suggesting a potential role of PADs in the development or maintenance of AML and the potential for the identification of novel therapeutic targets. METHODS: AML cells were treated in vitro with the pan-PAD inhibitor BB-Cl-Amidine (BB-Cl-A). The AML cell lines were effectively induced into apoptosis by BB-Cl-A. However, the PAD4-specific inhibitor GSK484 did not. RESULTS: PAD2 played a significant role in AML. Furthermore, we found that BB-Cl-A could activate the endoplasmic reticulum (ER) stress response, as evidenced by an increase in phosphorylated PERK (p-PERK) and eIF2α (p-eIF2α). As a result of the ER stress activation, the BB-Cl-A effectively induced apoptosis in the AML cells. CONCLUSION: Our findings indicated that PAD2 plays a role in ER homeostasis maintenance and apoptosis prevention. Therefore, targeting PAD2 with BB-Cl-A could represent a novel therapeutic strategy for treating AML.
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Leucemia Mieloide Aguda , Ornitina , Humanos , Histona Demetilasas , Leucemia Mieloide Aguda/tratamiento farmacológico , Ornitina/farmacología , Desiminasas de la Arginina Proteica/genética , Desiminasas de la Arginina Proteica/metabolismo , Estrés del Retículo EndoplásmicoRESUMEN
A superconducting nanowire single-photon imager (SNSPI) uses a time-multiplexing method to reduce the readout complexity. However, due to the serial connection, the nanowire should be uniform so that a common bias can set all segments of the nanowire to their maximum detection efficiency, which becomes more challenging as the scalability (i.e., the length of the nanowire) increases. Here, we have developed a 64-pixel SNSPI based on amorphous Mo80Si20 film, which yielded a uniform nanowire and slow transmission line. Adjacent detectors were separated by delay lines, giving an imaging field of 270 µm × 240 µm. Benefiting from the high kinetic inductance of Mo80Si20 films, the delay line gave a phase velocity as low as 4.6 µm/ps. The positions of all pixels can be read out with a negligible electrical cross talk of 0.02% by using cryogenic amplifiers. The timing jitter was 100.8 ps. Saturated internal quantum efficiency was observed at a wavelength of 1550â nm. These results demonstrate that amorphous film is a promising material for achieving SNSPIs with large scalability and high efficiency.
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Many classic and quantum devices need to operate at cryogenic temperatures, demanding advanced cryogenic digital electronics for processing the input and output signals on a chip to extend their scalability and performance. Here, we report a superconducting binary encoder with ultralow power dissipation and ultracompact size. We introduce a multigate superconducting nanowire cryotron (nTron) that functions as an 8-input OR gate within a footprint of approximately 0.5 µm2. Four cryotrons compose a 4-bit encoder that has a bias margin of 18.9%, an operation speed greater than 250 MHz, an average switching jitter of 75 ps, and a power dissipation of less than 1 µW. We apply this encoder to read out a superconducting-nanowire single-photon detector array whose pixel location is digitized into a 4-bit binary address. The small size of the nanowire combined with the low power dissipation makes nTrons promising for future monolithic integration.
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Scalable superconducting nanowire single photon detector (SNSPDs) arrays require cryogenic digital circuits for multiplexing the output detection pulses. Among existing superconducting digital devices, superconducting nanowire cryotron (nTron) is a three-terminal device with an ultra-compact size, which is promising for large scale monolithic integration. In this report, in order to evaluate the potential and possibility of using nTrons for reading and digitizing SNSPD signals, we characterized the grey zone, speed, timing jitter and power dissipation of a proper designed nTron. With a DC bias on the gate, the nTron can be triggered by a few µA high and nanoseconds wide input signal, showing the nTron was capable of reading an SNSPD pulse at the same signal level. The timing jitter depended on the input signal level. For a 20 µA high and 5 ns wide input pulse, the timing jitter was 33.3 ps, while a typical SNSPD's jitter was around 50 ps. With removing the serial inductors and operating it in an AC bias mode. The nTron was demonstrated to be operated at a clock frequency of 615.4 MHz, which was faster than the maximum counting rate of a typical SNSPD. In additional, with a 50 Ω bias resistor and biased at 17.6 µA, the nTron had a total power dissipation of 19.7 nW. Although RSFQ circuits are faster than nTrons, for reading SNSPD or other detector arrays that demands less operation speed, our results suggest a digital circuit made from nTrons could be another promising alternative.
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PURPOSE: This study was designed to determine the safety and clinical efficacy of metronomic chemotherapy combined with aromatase inhibitors (AIs) for hormone receptor (HR)-positive advanced breast cancer (ABC) patients who cannot tolerate conventional-dose chemotherapy. METHODS: Postmenopausal patients with HR-positive ABC, who exhibited disease progression after first-line AIs treatment and who could not tolerate or rejected conventional chemotherapy, were enrolled in this study. Patients received capecitabine 500 mg PO TID (could be reduced to 500 mg QD in case of adverse effects) and exemestane 25 mg QD (after PD with letrozole) or letrozole 2.5 mg QD (after PD with exemestane). The primary endpoints were safety and tolerance, the secondary endpoints were objective response rate (ORR), clinical benefit rate (CBR), progression-free survival (PFS), and time to treatment failure (TTF). RESULTS: In our analysis of 44 patients, the median age was 64 years (range 38-90) and 68.2% patients had at least two recurrences or metastatic lesions. Grade 3 toxicities (hand-foot syndrome) were observed only in 4 of the patients. Most patients exhibited no or mild toxicities. After a median follow-up of 14.8 months, ORR was 70.5%, CBR-77.3%, PFS-16.2 months, and TTF-14.4 months. CONCLUSIONS: Metronomic oral capecitabine combined with AIs showed good efficacy, minimal toxicities, and good tolerance in HR-positive patients with ABC. It is a potential treatment option especially for postmenopausal HR-positive ABC patients in poor general condition who cannot tolerate conventional chemotherapy. TRIAL REGISTRATION: Clinicaltrials.gov NCT01924078.
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Administración Metronómica , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Inhibidores de la Aromatasa/administración & dosificación , Neoplasias de la Mama/tratamiento farmacológico , Capecitabina/administración & dosificación , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Supervivencia sin Progresión , Estudios ProspectivosRESUMEN
OBJECTIVE: The purpose of this study is to explore the correlation between serum dipeptidyl peptidase IV (DPPIV) and chronic obstructive pulmonary disease (COPD) at its various disease states, analyze its applications in the prediction and diagnosis of COPD and test the possibility of DPPIV as the serologic marker for COPD screening. MATERIALS AND METHODS: Samples from 74 patients (42 cases with acute exacerbation of COPD or acute exacerbation COPD (AECOPD) and 32 cases with stable COPD) and 29 control subjects were collected in this study. Those patients with AECOPD were classified as COPD remission group if their clinical symptoms relieved after nonintravenous or oral hormone therapy for 7 ± 3 days. DPPIV concentration was measured by enzyme-linked immunosorbent assay, and the difference in serum concentration of DPPIV was compared among different groups. The correlation between DPPIV concentration and age, sex or smoking history was analyzed, and the diagnostic value of DPPIV was evaluated by receiver-operating characteristic (ROC) curve analysis. RESULTS: Serum DPPIV concentration was significantly lower in all COPD groups as compared with that in healthy control group (P < 0.001). Serum DPPIV concentration in AECOPD group was increased after treatment (P < 0.001). There was no significant correlation between DPPIV concentration and age, sex or smoking history (P > 0.05). ROC analysis indicated that serum DPPIV concentration in all groups showed a good diagnostic accuracy, especially in stable COPD and AECOPD groups. The area under the ROC curve values were 0.901 and 0.906, respectively, with a high specificity of 0.931 for both groups and a high sensitivity of 0.75 for stable COPD and 0.875 for AECOPD. CONCLUSIONS: Serum DPPIV concentration in patients with COPD is decreased significantly, and there is no correlation between serum DPPIV concentration and sex or age. Serum DPPIV not only is an independent predictive factor, but also of high value as a good serologic marker for the diagnosis of COPD.
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Dipeptidil Peptidasa 4/sangre , Regulación Enzimológica de la Expresión Génica , Enfermedad Pulmonar Obstructiva Crónica/sangre , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Estudios de Casos y Controles , Dipeptidil Peptidasa 4/genética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Fumar/sangre , Fumar/epidemiologíaRESUMEN
BACKGROUND: To determine the potential value of serum tumor markers in predicting pCR (pathological complete response) during neoadjuvant chemotherapy. MATERIALS AND METHODS: We retrospectively monitored the pro-, mid-, and post- neoadjuvant treatment serum tumor marker concentrations in patients with locally advanced breast cancer (stage II-III) who accepted pre-surgical chemotherapy or chemotherapy in combination with targeted therapy at Fudan University Shanghai Cancer Center between September 2011 and January 2014 and investigated the association of serum tumor marker levels with therapeutic effect. Core needle biopsy samples were assessed using immunohistochemistry (IHC) prior to neoadjuvant treatment to determine hormone receptor, human epidermal growth factor receptor 2(HER2), and proliferation index Ki67 values. In our study, therapeutic response was evaluated by pCR, defined as the disappearance of all invasive cancer cells from excised tissue (including primary lesion and axillary lymph nodes) after completion of chemotherapy. Analysis of variance of repeated measures and receiver operating characteristic (ROC) curves were employed for statistical analysis of the data. RESULTS: A total of 348 patients were recruited in our study after excluding patients with incomplete clinical information. Of these, 106 patients were observed to have acquired pCR status after treatment completion, accounting for approximately 30.5% of study individuals. In addition, 147patients were determined to be Her-2 positive, among whom the pCR rate was 45.6% (69 patients). General linear model analysis (repeated measures analysis of variance) showed that the concentration of cancer antigen (CA) 15-3 increased after neoadjuvant chemotherapy in both pCR and non-pCR groups, and that there were significant differences between the two groups (P=0.008). The areas under the ROC curves (AUCs) of pre-, mid-, and post-treatment CA15-3 concentrations demonstrated low-level predictive value (AUC=0.594, 0.644, 0.621, respectively). No significant differences in carcinoembryonic antigen (CEA) or CA12-5 serum levels were observed between the pCR and non-pCR groups (P=0.196 and 0.693, respectively). No efficient AUC of CEA or CA12-5 concentrations were observed to predict patient response toward neoadjuvant treatment (both less than 0.7), nor were differences between the two groups observed at different time points. We then analyzed the Her-2 positive subset of our cohort. Significant differences in CEA concentrations were identified between the pCR and non-pCR groups (P=0.039), but not in CA15-3 or CA12-5 levels (p=0.092 and 0.89, respectively). None of the ROC curves showed underlying prognostic value, as the AUCs of these three markers were less than 0.7. The ROC-AUCs for the CA12-5 concentrations of inter-and post-neoadjuvant chemotherapy in the estrogen receptor negative HER2 positive subgroup were 0.735 and 0.767, respectively. However, the specificity and sensitivity values were at odds with each other which meant that improving either the sensitivity or specificity would impair the efficiency of the other. CONCLUSIONS: Serum tumor markers CA15-3, CA12-5, and CEA might have little clinical significance in predicting neoadjuvant treatment response in locally advanced breast cancer.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biomarcadores de Tumor/sangre , Neoplasias de la Mama/sangre , Neoplasias de la Mama/tratamiento farmacológico , Terapia Neoadyuvante , Recurrencia Local de Neoplasia/sangre , Recurrencia Local de Neoplasia/tratamiento farmacológico , Adulto , Anciano , Neoplasias de la Mama/patología , Femenino , Estudios de Seguimiento , Humanos , Técnicas para Inmunoenzimas , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Pronóstico , Curva ROC , Receptor ErbB-2/metabolismo , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismo , Estudios Retrospectivos , Adulto JovenRESUMEN
OBJECTIVE: Studies have indicated that p53 protein accumulation exerts an adverse effect on the survival of breast cancer patients; however, the prognostic value of p53 protein accumulation for aromatase inhibitor (AI) resistance in ER-positive breast cancer is uncertain. METHODS: The expression level of p53 protein was detected by immunohistochemistry in primary early-stage ER-positive breast tumor specimens from 293 postmenopausal breast cancer patients who received first-line AI treatment (letrozole, anastrozole, or exemestane) until relapse, and analysis was performed to determine whether expression of p53 protein affected the response to endocrine therapy. RESULTS: Of the 293 invasive ductal carcinomas, 65.4% were positive for p53 protein expression. All patients received AI therapy as first-line treatment until relapse. The 5-year disease-free survival rates in p53-positive and p53-negative patients were 78% and 89%, respectively. Patients with primary breast tumors that had p53 protein accumulation showed significantly more resistance to AI treatment (hazard ratio=1.729, 95% confidence interval=1.038-2.880, P=0.035). CONCLUSION: This study demonstrated that p53 protein accumulation was helpful in choosing patients who may benefit from AI treatment and is a prognostic marker in ER-positive early-stage breast cancer.
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A multifunctional organic-inorganic hybrid nanocapsule based on Bi2S3-embedded poly (lactic-co-glycolic acid) (PLGA) nanocapsule has been elaborately designed to combine the merits of both polymeric shell structure and Bi2S3 nanoparticles. Hydrophobic Bi2S3 nanoparticles were successfully introduced into the PLGA nanocapsules via a facile and efficient water/oil/water (W/O/W) emulsion strategy. The elastic polymeric PLGA shell provides the excellent capability of ultrasound contrast imaging to the Bi2S3/PLGA. Meanwhile, the potential of these microcapsules to enhance the high intensity focused ultrasound (HIFU) therapy was demonstrated. Importantly, this research provided the first example of both in vitro and in vivo to demonstrate the radiosensitization effect of Bi2S3-embedded PLGA hybrid nanocapsules against prostate cancer under external X-ray irradiation. Thus, the successful integration of the Bi2S3 and PLGA nanocapsules provided an alternative strategy for the highly efficient ultrasound guided HIFU/RT synergistic therapy.
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Materiales Biocompatibles/química , Bismuto/química , Ácido Láctico/química , Ácido Poliglicólico/química , Sulfuros/química , Animales , Apoptosis , Línea Celular , Proliferación Celular , Medios de Contraste/química , Elasticidad , Humanos , Masculino , Ratones , Ratones Desnudos , Nanocápsulas/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Polímeros/química , Neoplasias de la Próstata/terapia , Conejos , Fármacos Sensibilizantes a Radiaciones/química , Temperatura , Ultrasonografía , Rayos XRESUMEN
OBJECTIVE: To construct a lentiviral expression vector of the PIAS-NY gene, and establish a mouse spermatocyte-derived cell line with a stable overexpression of PIAS-NY. METHODS: PIAS-NY was synthesized, amplified by PCR and cloned into the lentiviral vector expression plasmid pGC-FU. After digestion and sequencing, pGC-FU-PIAS-NY, pHelper 1.0 and pHelper 2.0 were co-transfected into 293T cells. Then the lentiviral particles were used to transfect the mouse spermatocyte-derived cells. The expression of the PIAS-NY protein was detected by Western blot. RESULTS: We successfully constructed the lentiviral expression vector pGC-FU-PIAS-NY and established a mouse spermatocyte-derived cell line with a stable overexpression of PIAS-NY. CONCLUSION: The construction of the lentiviral expression vector pGC-FU-PIAS-NY and the obtainment of stably transfected mouse spermatocyte-derived cells have paved the way for further studies on the roles of the PIAS-NY gene in spermatogenesis.
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Línea Celular , Proteínas Inhibidoras de STAT Activados/genética , Espermatocitos/citología , Transfección , Animales , Vectores Genéticos , Lentivirus/genética , Masculino , Ratones , PlásmidosRESUMEN
OBJECTIVE: To study the voice function rehabilitation by mucosa tube performed in operation of late laryngocarcinoma and to improve the survival quality of patients with late laryngocarcinoma. METHODS: Forty-six patients were treated between Oct. 1991 and May 2006, including 41 males and 5 females. The average age of the patients was 54. Seventeen cases were glottic carcinomas (T3N0M0 12, T3N1M0 5), 27 cases were supraglottic carcinomas (T3N1M0 16, T4N1M0 5, T3N0M0 6), 2 cases were pyriform sinus cancer (T4N1M0 2). For those patients with late laryngocarcinoma, who had lost the chance of partial laryngectomy, mucosa tube shaping during the operation could realize voice functional rehabilitation. Only the survive arytenoids of healthy side was preserved, in order to rehabilitate voice, a mucosa tube was sutured using healthy survive arytenoids and a mucosa strip was connected to the trachea and the mucosa of hypopharynx. Survival analysis was performed by using Kaplan-Meier method. RESULTS: Forty-one out of 46 patients obtained almost normal voice and swallow function. The 5-years survival was 76%. CONCLUSIONS: The operation of voice function rehabilitation by mucosa tube performed can get good voice and swallow function to patients with late laryngo carcinoma.
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Neoplasias Laríngeas , Laringectomía , Cartílago Aritenoides/cirugía , Humanos , Neoplasias Laríngeas/cirugía , Membrana Mucosa , Análisis de SupervivenciaRESUMEN
OBJECTIVE: To evaluate the effect of ethyl pyruvate (EP) in improving the survival and ameliorating distant organ damage and to investigate the role of high-mobility group box (HMGB) 1 in rats with established severe acute pancreatitis (SAP). METHODS: Severe acute pancreatitis was induced by retrograde infusion of sodium taurodeoxycholate (5%, 1 mL/kg) into the biliopancreatic ducts in male Wistar rats. The rats were infused intravenously with EP of 40 mg/kg, 4 mg/kg, and 0.4 mg/kg initiating 12 hours, and EP of 40 mg/kg was administered beginning 2 hours before surgery (-2 hours) and 12, 24, and 36 hours after induction of SAP; then, the mortality was recorded. Serum tumor necrosis factor alpha, interleukin (IL) 6, and IL-1beta were measured using enzyme-linked immunosorbent assay. High-mobility group box 1 levels were measured using Western immunoblotting analysis. RESULTS: Serum HMGB1 levels were increased dramatically after 12 hours, remained at high levels for 72 hours, and were significantly higher in rats with SAP than in those with mild and moderate pancreatitis (P < 0.01). Treatment with EP (40 mg/kg) conferred protection from lethality of SAP (EP survival [63%] vs vehicle survival [6.3%]; P < 0.001). No survival advantage occurred when treatment was initiated 36 hours after surgery, but administration beginning 2 hours before operation (-2 hours) and 12 and 24 hours after induction of SAP significantly increased survival. Ethyl pyruvate treatment significantly decreased serum HMGB1, tumor necrosis factor alpha, IL-1beta, and IL-6 levels and ameliorated extrapancreatic organ dysfunction in rats with SAP. CONCLUSIONS: Ethyl pyruvate improves survival and ameliorates distant organ injury of SAP. These beneficial effects of EP are because of the modulation of HMGB1 and other inflammatory cytokine responses.
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Antiinflamatorios no Esteroideos/uso terapéutico , Proteínas del Grupo de Alta Movilidad/sangre , Riñón/patología , Hígado/patología , Pancreatitis/tratamiento farmacológico , Piruvatos/uso terapéutico , Proteínas Represoras/sangre , Enfermedad Aguda , Animales , Antiinflamatorios no Esteroideos/administración & dosificación , Biomarcadores , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Evaluación Preclínica de Medicamentos , Proteína HMGB1 , Interleucina-1beta/sangre , Interleucina-6/sangre , Riñón/efectos de los fármacos , Hígado/efectos de los fármacos , Masculino , Pancreatitis/sangre , Pancreatitis/inducido químicamente , Pancreatitis/patología , Piruvatos/administración & dosificación , Distribución Aleatoria , Ratas , Ratas Wistar , Ácido Taurodesoxicólico/toxicidad , Factor de Necrosis Tumoral alfa/análisisRESUMEN
AIM: To study the effect of NS-398, a selective cyclooxygenase-2 (COX-2) inhibitor, on invasion of colon cancer cell line HT-29 in vitro and to explore its mechanisms. METHODS: Invasive behaviors of the malignant colon cancer cell line HT-29 were investigated in this study. Expressions of COX-2 and CD44v6 in HT-29 cells were detected by flow cytometry. Cellular survival rate was determined by MTT assay. The invasive capacity was quantified by a modified Boyden chamber model. Alterations of cytoskeleton component F-actin were observed by confocal laser scanning microscope. RESULTS: Flow cytometry analysis showed that COX-2 was highly expressed in HT-29 cells. The invasive capability of HT-29 cells could be greatly inhibited by NS-398 at the experimental concentrations of 0.1, 1.0 and 10 micormol/L with an inhibitory rate of 22.74%, 42.35% and 58.61% (P<0.01), respectively. MTT assay showed that NS-398 at the experimental concentrations had no significant influence on cellular viability, indicating that such anti-invasive effects had no relationship with cytotoxicity. F-actin was mainly distributed around nuclei forming annular structure in HT-29 cells. After exposure to NS-398 of 10 micromol/L, the annular structure around nuclei disappeared and the fluorescence intensity of F-actin decreased obviously. Treatment with NS-398 could down-regulate the expression of CD44v6 as well. CONCLUSION: NS-398 has anti-invasive effects on colon cancer HT-29 cells in vitro, which may be mediated by a novel mechanism of disruption of cytoskeleton. Down-regulation of CD44v6 expression may be related to alterations of cytoskeleton.
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Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , Inhibidores de la Ciclooxigenasa/farmacología , Nitrobencenos/farmacología , Sulfonamidas/farmacología , Actinas/efectos de los fármacos , Ciclooxigenasa 2 , Inhibidores de la Ciclooxigenasa 2 , Citoesqueleto/ultraestructura , Regulación hacia Abajo , Glicoproteínas/metabolismo , Células HT29 , Humanos , Receptores de Hialuranos/metabolismo , Isoenzimas/metabolismo , Proteínas de la Membrana , Invasividad Neoplásica/prevención & control , Prostaglandina-Endoperóxido Sintasas/metabolismoRESUMEN
OBJECTIVE: To investigate the fat decreasing effects of fenofibrate on alcoholic fatty liver and drug-induced fatty liver in rats. METHODS: Alcoholic fatty liver and drug-induced fatty liver rats models were established. The two kinds of rats with fatty liver were seperatedly divided into fenofibrate treatment group (80 mg/kg daily) and control group without treatment. Rats were killed after four weeks, then the levels of serum triglycerides (TG), total cholesterol (TC), high density lipoprotein (HDL) and malondialdehyde (MDA), hepatic lipase (HL), lipoprotein lipase (LPL) both in serum and liver tissue were measured according to the Test Kits. Histopathological changes in liver was dyed with HE and observed under light microscope. RESULTS: After treatment by fenofibrate, in the serum of rats with alcoholic fatty liver, the level of TG decreased significantly (1.07 mmol/L 0.06 mmol/L vs 1.56 mmol/L 0.29 mmol/L, t=5.115, p<0.001), while the level of TC had no alteration. The levels of MDA both in serum and liver tissue decreased (1.10 nmol/L 0.22 nmol/L vs 1.26 nmol/L 0.21 nmol/L, t=0.592, p<0.05; 5.92 nmol/g 1.24 nmol/g vs 7.42 nmol/g 1.22 nmol/g, t=3.477, p<0.05, respectively), while the levels of HL, LPL in serum and liver tissue increased significantly (Serum: 0.053muEq/ml/h 0.006muEq/ml/h vs 0.037 muEq/ml/h 0.006muEq/ml/h, t=-5.086, p<0.001; 0.018 muEq/ml/h 0.004 muEq/ml/h vs 0.014muEq/ml/h 0.004muEq/ml/h, t=-2.485, p<0.05. Liver tissue: 0.075muEq/ml/h 0.010muEq/ml/h vs 0.065muEq/ml/h 0.007muEq/ml/h, t=-2.437, p<0.05; 0.022 muEq/ml/h 0.014 muEq/ml/h vs 0.008 muEq/ml/h 0.002 muEq/ml/h, t=-2.876, p<0.05). Fat content in liver decreased (26.01 mg/g 1.69 mg/g vs 71.45 mg/g 2.66 mg/g, t=-43.224, p<0.001). The pathological changes of liver in fenofibrate-treated rats with alcoholic fatty liver were improved. For the drug-induced fatty liver rats, fenofibrate treatment group had no difference from the untreated control group. CONCLUSION: Fenofibrate can significantly decrease the fat content in liver tissue of rats with alcoholic fatty liver, as well as ameliorating liver pathological changes. But fenofibrate has no effect on drug-induced fatty liver.