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1.
Neural Regen Res ; 18(3): 683-688, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36018194

RESUMEN

Percutaneous electrical nerve stimulation of an injured nerve can promote and accelerate peripheral nerve regeneration and improve function. When performing acupuncture and moxibustion, locating the injured nerve using ultrasound before percutaneous nerve stimulation can help prevent further injury to an already injured nerve. However, stimulation parameters have not been standardized. In this study, we constructed a multi-layer human forearm model using finite element modeling. Taking current density and activated function as optimization indicators, the optimal percutaneous nerve stimulation parameters were established. The optimal parameters were parallel placement located 3 cm apart with the injury site at the midpoint between the needles. To validate the efficacy of this regimen, we performed a randomized controlled trial in 23 patients with median nerve transection who underwent neurorrhaphy. Patients who received conventional rehabilitation combined with percutaneous electrical nerve stimulation experienced greater improvement in sensory function, motor function, and grip strength than those who received conventional rehabilitation combined with transcutaneous electrical nerve stimulation. These findings suggest that the percutaneous electrical nerve stimulation regimen established in this study can improve global median nerve function in patients with median nerve transection.

2.
Front Neurol ; 13: 903207, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36090881

RESUMEN

Introduction: Spinal cord injury causes permanent neurological deficits, which have devastating physical, social, and vocational consequences for patients and their families. Traditional Chinese medicine uses acupuncture to treat neuropathic pain and improve nerve conduction velocity. This treatment can also reduce peripheral nerve injury joint contracture and muscle atrophy in affected patients. And it's got a remarkable restoration when electrical stimulation therapy on impaired peripheral nerves in animal models and clinical trials. Case description: A 48-year-old woman was hit by a heavy object that injured her lower back. The patient had a T12-L1 vertebral flexion and stretch fracture with traumatic spinal stenosis. The patient was transferred to the rehabilitation department after posterior T12-L2-segment pedicle screw system distraction and reduction, internal fixation, decompression, and bone graft fusion. Ultrasound-guided electroacupuncture was used to stimulate the sacral nerve, the spinal nerve, and the head of the patient, accompanied by spinal joint loosening training, respiratory training, lumbar comprehensive sports training, paraplegic limbs comprehensive training, and other manipulative treatment. Outcomes: After the intervention, the patient showed significant improvements in sensory and motor scores, resulting in functional recovery according to ASIA and FIM. The patient gradually showed reasonable functional remission. Discussion: The sacral nerve, the spinal cord, and the head were electrically stimulated by ultrasound-guided electroacupuncture in terms of intervention, and various functions of the patient were alleviated to a certain extent. The efficacy of ultrasound-guided electroacupuncture stimulation in treating neurologic symptoms should be validated in future clinical trials.

3.
Nanoscale ; 14(18): 7049-7054, 2022 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-35475485

RESUMEN

The fabrication procedure for each layer of the device in monolithic three-dimensional (3D) integration still follows the design philosophy of traditional planar silicon-based circuits, and such integrated circuits will ultimately be limited by the same scaling constraints that face silicon field-effect transistors. We report the direct formation of laminated 3D integrated circuits by the layer-by-layer stacking of each component through two different techniques. One is to use carbon nanotubes (CNTs) as the channels of thin-film transistors because of their low-temperature fabrication and layer-to-layer transfer capabilities. The other is to use a suitable separator between every two layers to isolate them, because the separator is not only able to maintain the stability of the performance of each component after coating, but is also a good insulator that can prevent interlayer interactions. A 5-stage CNT ring oscillator laminated onto a single inverter is finally reported, which can reduce the device area by approximately 80%, and should be greatly helpful for the continuous improvement of device functionality and integration.

4.
Adv Mater ; 34(17): e2201298, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35226775

RESUMEN

As a rapidly growing family of 2D transition metal carbides and nitrides, MXenes are recognized as promising materials for the development of future electronics and optoelectronics. So far, the reported patterning methods for MXene films lack efficiency, resolution, and compatibility, resulting in limited device integration and performance. Here, a high-performance MXene image sensor array fabricated by a wafer-scale combination patterning method of an MXene film is reported. This method combines MXene centrifugation, spin-coating, photolithography, and dry-etching and is highly compatible with mainstream semiconductor processing, with a resolution up to 2 µm, which is at least 100 times higher than other large-area patterning methods reported previously. As a result, a high-density integrated array of 1024-pixel Ti3 C2 Tx /Si photodetectors with a detectivity of 7.73 × 1014 Jones and a light-dark current ratio (Ilight /Idark ) of 6.22 × 106 , which is the ultrahigh value among all reported MXene-based photodetectors, is fabricated. This patterning technique paves a way for large-scale high-performance MXetronics compatible with mainstream semiconductor processes.

5.
Nat Commun ; 12(1): 1798, 2021 03 19.
Artículo en Inglés | MEDLINE | ID: mdl-33741964

RESUMEN

The challenges of developing neuromorphic vision systems inspired by the human eye come not only from how to recreate the flexibility, sophistication, and adaptability of animal systems, but also how to do so with computational efficiency and elegance. Similar to biological systems, these neuromorphic circuits integrate functions of image sensing, memory and processing into the device, and process continuous analog brightness signal in real-time. High-integration, flexibility and ultra-sensitivity are essential for practical artificial vision systems that attempt to emulate biological processing. Here, we present a flexible optoelectronic sensor array of 1024 pixels using a combination of carbon nanotubes and perovskite quantum dots as active materials for an efficient neuromorphic vision system. The device has an extraordinary sensitivity to light with a responsivity of 5.1 × 107 A/W and a specific detectivity of 2 × 1016 Jones, and demonstrates neuromorphic reinforcement learning by training the sensor array with a weak light pulse of 1 µW/cm2.

6.
Zhongguo Zhong Yao Za Zhi ; 46(24): 6502-6510, 2021 Dec.
Artículo en Chino | MEDLINE | ID: mdl-34994143

RESUMEN

This study aimed to investigate the effect of methyl eugenol(ME) on hypoxia/reoxygenation(H/R)-induced injury of human renal tubular epithelial HK-2 cells and its mechanism. The viability of HK-2 cells cultured with different concentrations of ME and exposed to H/R was detected by cell counting kit-8(CCK-8) assay. The effect of ME on the morphology of HK-2 cells was observed under an inverted microscope. The content of intracellular reactive oxygen species in different groups was detected after 2',7'-dichlorodihydrofluorescein diacetate(DCFH-DA) fluorescence staining. Cell apoptosis was determined by flow cytometry. Changes in mitochondrial membrane potential were monitored by JC-1 dye. The concentrations of nuclear factor erythroid 2 related factor 2(Nrf2), heme oxygenase-1(HO-1), and nicotinamide adenine dinucleotide phosphatase oxidase 4(Nox4) were measured by Western blot, followed by the assay of Nrf2 concentration changes in cytoplasm and nucleus by confocal fluorescence staining. The results showed that when the concentration of ME was 0-40 µmol·L~(-1), the activity of HK-2 cells was not affected. Compared with the model group, ME enhanced the activity of HK-2 cells and the cell morphology was normal. As revealed by further experiments, ME inhibited the release of reactive oxygen species and the decline in mitochondrial membrane potential of HK-2 cells after H/R injury, promoted Nrf2/HO-1 expression and Nrf2 translocation to the nucleus, and down-regulated the expression of Nox4, thereby significantly reducing apoptosis. This protective effect of ME could be reversed by the specific Nrf2 inhibitor ML385. These findings have preliminarily proved that ME effectively protected HK-2 cells against H/R injury, which might be related to its promotion of Nrf2/HO-1 signaling pathway and inhibition of Nox4. Such exploration on the possible mechanism of ME in the treatment of renal ischemia-reperfusion injury(IRI) and protection of organ function from the perspective of antioxidant stress has provided reference for related research on the treatment of acute kidney injury with traditional Chinese medicine.


Asunto(s)
Eugenol , Daño por Reperfusión , Apoptosis , Células Epiteliales/metabolismo , Eugenol/análogos & derivados , Eugenol/farmacología , Hemo-Oxigenasa 1/metabolismo , Humanos , Hipoxia , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Estrés Oxidativo , Especies Reactivas de Oxígeno , Daño por Reperfusión/tratamiento farmacológico
7.
World J Clin Cases ; 8(14): 3097-3107, 2020 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-32775392

RESUMEN

BACKGROUD: Follicular dendritic cell (FDC) sarcomas are rare neoplasms that occur predominantly in the lymph nodes. They can also occur extranodally. Extranodal FDC sarcomas most commonly present as solitary masses. Inflammatory pseudotumor (IPT)-like FDC sarcomas, a subcategory of FDC sarcomas, are rarer than other sarcoma subtypes. They are composed of spindle or ovoid neoplastic cells and exhibit an admixture of plasma cells and prominent lymphoplasmacytic infiltration. Paraneoplastic pemphigus (PNP), also known as paraneoplastic autoimmune multiorgan syndrome, is a rare autoimmune bullous disease that is associated with underlying neoplasms. PNP has a high mortality, and its early diagnosis is usually difficult. CASE SUMMARY: We describe a 27-year-old woman who presented with stomatitis, conjunctivitis, and skin blisters and erosions as her first symptoms of PNP with an intra-abdominal IPT-like FDC sarcoma. The patient underwent surgical tumor resection and received tapering oral corticosteroid treatment. She showed no recurrence at the 1-year follow-up. CONCLUSION: IPT-like FDC sarcomas are rare underlying neoplasms that have an uncommon association with PNP. PNP-associated FDC sarcomas predominantly occur in intra-abdominal sites and suggest a poor prognosis. Surgical resection is an essential and effective treatment for PNP and primary and recurrent FDC sarcomas.

8.
Adv Mater ; 32(9): e1907288, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31977113

RESUMEN

In a modern electronics system, charge-coupled devices and data storage devices are the two most indispensable components. Although there has been rapid and independent progress in their development during the last three decades, a cofunctionality of both sensing and memory at single-unit level is yet premature for flexible electronics. For wearable electronics that work in ultralow power conditions and involve strains, conventional sensing-and-memory systems suffer from low sensitivity and are not able to directly transform sensed information into sufficient memory. Here, a new transformative device is demonstrated, which is called "sen-memory", that exhibits the dual functionality of sensing and memory in a monolithic integrated circuit. The active channel of the device is formed by a carbon nanotube thin film and the floating gate is formed by a controllably oxidized aluminum nanoparticle array for electrical- and optical-programming. The device exhibits a high on-off current ratio of ≈106 , a long-term retention of ≈108 s, and durable flexibility at a bending strain of 0.4%. It is shown that the device senses a photogenerated pattern in seconds at zero bias and memorizes an image for a couple of years.

9.
J Asian Nat Prod Res ; 22(8): 746-753, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31163996

RESUMEN

Zeaxanthin dipalmitate (3) and two zeaxanthin dipalmitate derivatives, including one new compound (1), were obtained from wolfberry [the fruit of Lycium barbarum L. (Solanaceae)]. Their structures were unambiguously elucidated by spectroscopic analyses. Compound 2 is isolated from the genus Lycium for the first time, and its 1D/2D NMR data are firstly reported. All the compounds belong to carotenoids which are a kind of major bioactive constituents in wolfberry and are also responsible for wolfberry's red color.


Asunto(s)
Lycium , Frutas , Estructura Molecular , Palmitatos , Xantófilas
10.
Phytochemistry ; 164: 60-66, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31096077

RESUMEN

Fifteen phenylpropanoid glycosides, including six undescribed compounds were isolated from the fruit of Lycium barbarum L. (Solanaceae) (goji or wolfberry). Their structures were identified by detailed spectroscopic analyses. Seven known compounds were firstly isolated from the genus Lycium, in which the 1D and 2D NMR data of one compound were reported for the first time. Notably, two undescribed compounds were a pair of rare tautomeric glycoside anomers characterized by the presence of free anomeric hydroxy. Antioxidant and hypoglycemic activities of all these compounds were assessed using DPPH radical scavenging, oxygen radical absorbance capacity (ORAC), and α-glucosidase inhibitory assays, respectively. These compounds showed different levels of oxygen radical absorbance capacity, and some isolates exhibited potent antioxidant activity with greater ORAC values than the positive control (EGCG).


Asunto(s)
Antioxidantes/farmacología , Frutas/química , Inhibidores de Glicósido Hidrolasas/farmacología , Glicósidos/farmacología , Lycium/química , Fenilpropionatos/farmacología , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Compuestos de Bifenilo/antagonistas & inhibidores , Relación Dosis-Respuesta a Droga , Inhibidores de Glicósido Hidrolasas/química , Inhibidores de Glicósido Hidrolasas/aislamiento & purificación , Glicósidos/química , Glicósidos/aislamiento & purificación , Conformación Molecular , Fenilpropionatos/química , Fenilpropionatos/aislamiento & purificación , Picratos/antagonistas & inhibidores , Especies Reactivas de Oxígeno/antagonistas & inhibidores , Relación Estructura-Actividad , alfa-Glucosidasas/metabolismo
11.
ACS Appl Mater Interfaces ; 11(12): 11699-11705, 2019 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-30839190

RESUMEN

Carbon nanotube (CNT) thin-film transistors are expected to be promising for use in flexible electronics including flexible and transparent integrated circuits and in wearable chemical and physical sensors and for driving the circuits of flexible display panels. However, current devices based on CNT channels suffer from poor performance uniformity and low manufacturing yield; therefore, they are still far from being practical. This is usually caused by nonuniform deposition of the semiconducting CNTs and the rough surface of flexible substrates. Here, we report CNT thin-film transistors (TFTs) driving a flexible 64 × 64 pixel active matrix light-emitting diode display (AMOLED) by improving the formation of uniform CNT films and developing a new pretreatment technique for flexible substrates. The achieved AMOLED has uniform brightness and a high yield of 99.93% in its 4096 pixels. More than 8000 TFTs with high-purity semiconducting CNTs as the channel material show an average on-off current ratio of ∼107 and a carrier mobility of 16 cm2 V-1 s-1. The standard deviations of the on-state current and the carrier mobility are 4.1 and 6.5%, respectively. Our result shows that the panel driven by high-purity semiconducting CNTs is a promising strategy for the development of next-generation flexible, large-area displays.

12.
BMC Urol ; 18(1): 79, 2018 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-30200918

RESUMEN

BACKGROUND: BRAF-activated long non-coding RNA (BANCR) has been associated with various types of cancer. Nevertheless, the role of BANCR in clear cell renal cell carcinoma (ccRCC) is still not fully understood. This study aims to investigate the relationship between ccRCC and BANCR. METHODS: Expression of BANCR in TCGA renal cancer data sets was analyzed. The expression pattern of BANCR in Immortalized normal human proximal tubule epithelial cell line HK-2 and ccRCC cell lines (ACHN, CAKI-1, A498 and 786-O) was detected by real-time quantitative RT-PCR (qRT-PCR). ccRCC tissues with adjacent normal renal tissues diagnosed by pathological methods from 62 patients were used to detect the expression of BANCR, and its correlation with prognosis of ccRCC patients was assessed by Kaplan-Meier method. The LV-BANCR vector was used to examine the influence of BANCR on the proliferation, migration, invasion, apoptosis and cell cycle distribution of ccRCC cells in vitro. RESULTS: BANCR was downregulated in renal cancer according to TCGA data sets. Compared with adjacent normal renal tissues and normal human proximal tubule epithelial cell line HK-2, BANCR expression was significantly decreased in ccRCC tissues and ccRCC cell lines, and its low expression was associated with poor prognosis. Moreover, in the condition of BANCR overexpression by LV-BANCR vector, the proliferation, migration, invasion capacity of ccRCC cells was inhibited, while the apoptosis was increased and the G1 cell cycle arrest was induced in vitro. CONCLUSIONS: BANCR is downregulated in ccRCC tissues and cell lines, and is associated with ccRCC progression. Thus, BANCR may represent a novel prognostic biomarker and a potential therapeutic target for ccRCC patients.


Asunto(s)
Carcinoma de Células Renales/metabolismo , Regulación Neoplásica de la Expresión Génica , Neoplasias Renales/metabolismo , Proteínas Proto-Oncogénicas B-raf/metabolismo , ARN Largo no Codificante/metabolismo , Biomarcadores de Tumor , Carcinoma de Células Renales/genética , Línea Celular Tumoral , Proliferación Celular , Regulación hacia Abajo , Humanos , Estimación de Kaplan-Meier , Riñón/metabolismo , Neoplasias Renales/genética , Pronóstico , Proteínas Proto-Oncogénicas B-raf/genética
13.
Adv Sci (Weinh) ; 5(5): 1700965, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29876218

RESUMEN

This study reports a simple and effective technique for the high-throughput fabrication of flexible all-carbon nanotube (CNT) electronics using a photosensitive dry film instead of traditional liquid photoresists. A 10 in. sized photosensitive dry film is laminated onto a flexible substrate by a roll-to-roll technology, and a 5 µm pattern resolution of the resulting CNT films is achieved for the construction of flexible and transparent all-CNT thin-film transistors (TFTs) and integrated circuits. The fabricated TFTs exhibit a desirable electrical performance including an on-off current ratio of more than 105, a carrier mobility of 33 cm2 V-1 s-1, and a small hysteresis. The standard deviations of on-current and mobility are, respectively, 5% and 2% of the average value, demonstrating the excellent reproducibility and uniformity of the devices, which allows constructing a large noise margin inverter circuit with a voltage gain of 30. This study indicates that a photosensitive dry film is very promising for the low-cost, fast, reliable, and scalable fabrication of flexible and transparent CNT-based integrated circuits, and opens up opportunities for future high-throughput CNT-based printed electronics.

14.
Adv Mater ; 30(32): e1802057, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29952030

RESUMEN

Single-wall carbon nanotubes (SWCNTs), especially in the form of large-area and high-quality thin films, are a promising material for use in flexible and transparent electronics. Here, a continuous synthesis, deposition, and transfer technique is reported for the fabrication of meter-scale SWCNT thin films, which have an excellent optoelectrical performance including a low sheet resistance of 65 Ω/◽ with a transmittance of 90% at a wavelength of 550 nm. Using these SWCNT thin films, high-performance all-CNT thin-film transistors and integrated circuits are demonstrated, including 101-stage ring oscillators. The results pave the way for the future development of large-scale, flexible, and transparent electronics based on CNT thin films.

15.
J Nanosci Nanotechnol ; 15(4): 3212-7, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26353565

RESUMEN

Vertically aligned carbon nanotube (VACNT) array/polymer composite has already been recognized as a promising candidate for advanced thermal pad in thermal management of high-power electronic devices. However, the thermal conductive performance of this composite was limited by the quality of CNTs arrays. In this study, pre-annealing treatment was used to purify CNT arrays and improve thermal conductive performance of VACNT arrays/silicone composite. The thermal conductivity of the composite was enhanced by 34.52% and the thermal interface resistance was also reduced by 65.94% at a pre-annealing temperature of 490 °C for 5 min. The annealing process could remove some amorphous carbon and open the tips of CNTs. As a result, the interfacial compatibility in composite between carbon nanotube and polymer matrix was improved. The cyclic compression and tension performance of VACNT/S160 composite was investigated for further application.

16.
Int J Clin Exp Pathol ; 8(4): 3765-74, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26097558

RESUMEN

OBJECTIVE: accumulating evidence suggest that long non-coding RNAs (lncRNAs) may play important roles in human cancers. LncRNA neuroblastoma associated transcript-1 (NBAT-1) was initially identified to be involved in the progression of neuroblastoma. However, there is no report about the role of NBAT-1 in clear cell renal cell carcinoma (ccRCC). The purpose of this study is to investigate the clinical significant of NBAT-1 in ccRCC. METHODS: the expression pattern of NBAT-1 in ccRCC patients and renal cancer cell lines was detected by using quantitative real-time PCR (qRT-PCR), and its correlation with clinicopathologic features and prognosis of patients with ccRCC was assessed by Kaplan-Meier method and Cox proportional hazards model, respectively. Small interfering RNA (siRNA) was transfected into 786-O and ACHN cells to determine the effect of NBAT-1 knockdown on renal cancer cells. RESULT: NBAT-1 expression is significantly decreased in ccRCC tissues and renal cancer cells compared with adjacent normal tissues and normal human proximal tubule epithelial cell line HK-2, and its low level is associated with advanced features and poor prognosis. Also, multivariate analysis identified NBAT-1 expression as an independent prognostic factor for ccRCC. In vitro assays indicated that knockdown of NBAT-1 expression increased renal cancer cell proliferation, migration and invasion. CONCLUSIONS: NBAT-1 is a novel molecular correlated with ccRCC progression; and it may represent a prognostic biomarker and therapeutic target in renal cancer diagnosis and treatment.


Asunto(s)
Carcinoma de Células Renales/metabolismo , Neoplasias Renales/metabolismo , ARN Largo no Codificante/metabolismo , Anciano , Carcinoma de Células Renales/genética , Carcinoma de Células Renales/mortalidad , Carcinoma de Células Renales/patología , Línea Celular Tumoral , Proliferación Celular , Progresión de la Enfermedad , Femenino , Humanos , Neoplasias Renales/genética , Neoplasias Renales/mortalidad , Neoplasias Renales/patología , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Pronóstico , ARN Largo no Codificante/genética , ARN Interferente Pequeño , Tasa de Supervivencia
17.
Med Sci Monit ; 21: 1057-65, 2015 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-25863938

RESUMEN

BACKGROUND: A fusion protein composed of heme oxygenase-1 (HO-1) and cell-penetrating peptide PEP-1 has been shown to reduce local intestinal injury after intestinal ischemia/reperfusion (I/R). In this study, we investigated the effects of PEP-1-HO-1 fusion protein on remote organ injury induced by intestinal I/R in rats. MATERIAL AND METHODS: We randomly assigned 24 male Sprague-Dawley rats to 3 groups: Sham, I/R, and I/R plus PEP-1-HO-1 treatment (HO). The model of intestinal I/R was established by occluding the superior mesenteric artery for 45 min followed by 120-min reperfusion. In HO group, PEP-1-HO-1 was administered intravenously 30 min before ischemia, while animals in the Sham and I/R groups received the equal volume of physiological saline. At the end of the experiment, lung, liver, and blood samples were collected and analyzed. RESULTS: Malondialdehyde levels and histological injury scores were increased, and superoxide dismutase activities were decreased in the lung and liver tissues in the I/R group compared with the Sham group (P<0.05). Serum levels of alanine aminotransferase, aspartate aminotransferase, tumor necrosis factor-α, interleukin-6, and lung tissue wet weight to dry weight ratio were increased in the I/R group compared with the Sham group (P<0.05). NF-κB expression in intestinal tissues was significantly higher in the I/R group than in the Sham group. These changes were significantly reversed by treatment with PEP-1-HO-1. CONCLUSIONS: This study demonstrates that administration of PEP-1-HO-1 has a protective role against lung and liver injury after intestinal I/R, attributable to the reduction of released proinflammatory cytokines regulated by NF-κB.


Asunto(s)
Hemo-Oxigenasa 1/uso terapéutico , Intestinos/irrigación sanguínea , Hígado/patología , Pulmón/patología , Proteínas Recombinantes de Fusión/uso terapéutico , Daño por Reperfusión/terapia , Transducción Genética , Alanina Transaminasa/sangre , Animales , Aspartato Aminotransferasas/sangre , Hemo-Oxigenasa 1/genética , Interleucina-6/sangre , Intestinos/patología , Hígado/enzimología , Pulmón/enzimología , Masculino , Malondialdehído/metabolismo , FN-kappa B/metabolismo , Tamaño de los Órganos , Ratas Sprague-Dawley , Proteínas Recombinantes de Fusión/genética , Daño por Reperfusión/sangre , Daño por Reperfusión/patología , Superóxido Dismutasa/metabolismo , Factor de Necrosis Tumoral alfa/sangre
18.
Sci Rep ; 3: 2263, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23877331

RESUMEN

Oxygen conversion process between O2 and H2O by means of electrochemistry or photochemistry has lately received a great deal of attention. Cobalt-phosphate (Co-Pi) catalyst is a new type of cost-effective artificial oxygen-evolving complex (OEC) with amorphous features during photosynthesis. However, can such Co-Pi OEC also act as oxygen reduction reaction (ORR) catalyst in electrochemical processes? The question remains unanswered. Here for the first time we demonstrate that Co-Pi OEC does be rather active for the ORR. Particularly, Co-Pi OEC anchoring on reduced graphite oxide (rGO) nanosheet is shown to possess dramatically improved electrocatalytic activities. Differing from the generally accepted role of rGO as an "electron reservoir", we suggest that rGO serves as "peroxide cleaner" in enhancing the electrocatalytic behaviors. The present study may bridge the gap between photochemistry and electrochemistry towards oxygen conversion.


Asunto(s)
Cobalto/química , Grafito/química , Nanoestructuras/química , Óxidos/química , Oxígeno/química , Fosfatos/química , Catálisis , Electroquímica , Nanoestructuras/ultraestructura , Fotoquímica , Espectroscopía de Fotoelectrones , Agua/química
19.
Am J Chin Med ; 41(3): 665-82, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23711148

RESUMEN

Norcantharidin (NCTD) is currently used for anticancer therapy but the exact mechanism of action remains unknown. Pre-replicative complexes (pre-RCs) are essential for cell DNA replication and highly related to malignant proliferation. Here, we examined the inhibitory effect of NCTD on pre-RC components in HepG2 cells. We showed that NCTD induced degradation of Cdc6 and Mcm2 in a dose-dependent manner. Under 100 µM NCTD concentration, about 70% of Cdc6 and 50% of Mcm2 were degraded. In addition, the nuclear translocation of Mcm6 was inhibited by NCTD. Further studies aiming at G1 synchronous cells showed that, NCTD reduced the chromatin-bound Cdc6, Mcm2 and Mcm6. Moreover, the cells were blocked from entering the S phase and accumulated at the G1 phase when released synchronously into the cell cycle. Consistently, the DNA replication was inhibited by NCTD. Finally, the combination NCTD with Cdc6 depletion lead to more severe cytotoxicity (88%) than NCTD (52%) and Cdc6 depletion (39%) alone. A synergic cytotoxicity was observed between Cdc6 depletion and NCTD. In conclusion, our results demonstrate that NCTD inhibits pre-RC assembly; subsequently blocks the G1 to S transition; and inhibits DNA replication in HepG2 cells. Pre-RCs are an intriguing target for cancer therapy, which merits further investigations for anticancer development.


Asunto(s)
Antineoplásicos/uso terapéutico , Compuestos Bicíclicos Heterocíclicos con Puentes/uso terapéutico , Proteínas de Ciclo Celular/metabolismo , Ciclo Celular/efectos de los fármacos , Replicación del ADN/efectos de los fármacos , Neoplasias Hepáticas/tratamiento farmacológico , Proteínas Nucleares/metabolismo , Antineoplásicos/farmacología , Transporte Biológico , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Cantaridina/análogos & derivados , Cantaridina/farmacología , Cantaridina/uso terapéutico , Núcleo Celular/efectos de los fármacos , Cromatina/metabolismo , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Componente 2 del Complejo de Mantenimiento de Minicromosoma , Componente 6 del Complejo de Mantenimiento de Minicromosoma
20.
ACS Nano ; 6(5): 4288-97, 2012 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-22494330

RESUMEN

The tensile properties of carbon nanotube (CNT) fibers have been widely studied. However, the knowledge of their compressive properties is still lacking. In this work, the compressive properties of both pure CNT fibers and epoxy infiltrated CNT fibers were studied using the tensile recoil measurement. The compressive strengths were obtained as 416 and 573 MPa for pure CNT fibers and CNT-epoxy composite fibers, respectively. In addition, microscopic analysis of the fiber surface morphologies revealed that the principal recoil compressive failure mode of pure CNT fiber was kinking, while the CNT-epoxy composite fibers exhibited a failure mode in bending with combined tensile and compressive failure morphologies. The effect of resin infiltration on CNT fiber compressive properties, including the compressive strength and the deformation mode, is discussed. This work expands the knowledge base of the overall mechanical properties of CNT fibers, which are essential for their application in multifunctional composites.

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