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Ammonia has been emerging as a sustainable and environmentally friendly fuel. However, direct electrochemical ammonia oxidation reaction (AOR) in low-temperature fuel cells seriously suffers from high overpotential and deficient durability. Herein, rhombic dodecahedron nanoframe of platinum iridium copper (PtIrCu) with high-index faceted hyperbranched nanodendrites (RDNF-HNDs) was developed using a one-step self-etching solvothermal method. The framework structure with the high-index facets enables the PtIrCu nanocrystals to expose more effective active sites. They exhibit an ultra-low onset potential of 0.33 V vs. RHE and high mass activity of 26.1 A gPtIr-1 at 0.50 V, which is 140 mV lower and 7.5 times higher than that of commercial Pt/C in the AOR. In situ attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy verifies that AOR on PtIrCu RDNF-HNDs prefers to the NHx dimerization pathways, effectively alleviating the poison of Nads and NOx. The theoretical calculation also shows that both introducing Cu atoms into PtIr alloy and increasing the content of Ir in PtIrCu alloy can reduce the reaction energy barrier of electrochemical dehydrogenation from *NH2 to *NH. The specific structure of PtIrCu RDNF-NDs provides a new inspiration to solve the critical issue of electrocatalysts for AOR with low activity and durability.
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Gene annotation is essential for genome-based studies. However, algorithm-based genome annotation is difficult to fully and correctly reveal genomic information, especially for species with complex genomes. Artemisia annua L. is the only commercial resource of artemisinin production though the content of artemisinin is still to be improved. Genome-based genetic modification and breeding are useful strategies to boost artemisinin content and therefore, ensure the supply of artemisinin and reduce costs, but better gene annotation is urgently needed. In this study, we manually corrected the newly released genome annotation of A. annua using second- and third-generation transcriptome data. We found that incorrect gene information may lead to differences in structural, functional, and expression levels compared to the original expectations. We also identified alternative splicing events and found that genome annotation information impacted identifying alternative splicing genes. We further demonstrated that genome annotation information and alternative splicing could affect gene expression estimation and gene function prediction. Finally, we provided a valuable version of A. annua genome annotation and demonstrated the importance of gene annotation in future research.
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Artemisia annua , Artemisininas , Artemisia annua/genética , Empalme Alternativo/genética , Fitomejoramiento , GenómicaRESUMEN
Platinum-based alloy nanowire catalysts demonstrates great promise as electrocatalysts to facilitate the cathodic oxygen reduction reaction (ORR) of proton exchange membrane fuel cells (PEMFCs). However, it is still challenge to further improve the Pt atom utilization of Pt based nanowires featuring inherent structural stability. Herein, a new structure of PtCo nanowire with nanodendrites was developed using CO-assistance solvent thermal method. The dendrite structure with an average length of about 7 nm are characterized by a Pt-rich surface and the high-index facets of {533}, {331} and {311}, and grows from the ultra-fine wire structure with an average diameter of about 3 nm. PtCo nanowires with nanodendrites developed in this work shows outstanding performance for ORR, in which its mass activity of 1.036 A/mgPt is 5.76 times, 1.74 times higher than that of commercial Pt/C (0.180 A/mgPt) and PtCo nanowires without nanodendrites (0.595 A/mgPt), and its mass activity loss is only 18% under the accelerated durability tests (ADTs) for 5k cycles. The significant improvement is attributed to high exposure of active sites induced by the dendrite structure with Pt-rich surface with the high-index facets and Pt-rich surface. This structure may provide a new idea for developing novel 1D Pt based electrocatalysts.
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Despite the remarkable research efforts, the lack of ideal activity and state-of-the-art electrocatalysts remains a substantial challenge for the global application of fuel cell technology. Herein, is reported the synthesis of Au@PtNiAu concave octahedral core-shell nanocatalysts (Au@PtNiAu-COCS) via solvothermal synthesis modification and optimization approach. The special structure generating a large number of step atoms, enhancing the oxygen reduction reaction (ORR) and methanol oxidation reaction (MOR) activity and stability. The superior ORR mass activity of the Au@PtNiAu-COCS is 11.22 times than the exhibited of Pt/C initially by Pt loading, and 5.11 times by Pt + Au loading. After 30 k cycles the mass activity remains 78.8% (8.83 times the initial Pt/C activity) and the half-wave potential only shifts 12 mV. Au@PtNiAu-COCS has superior half-cell activity and gives ideal membrane electrode assemblies. Furthermore, for MOR the Au@PtNiAu-COCS show enhanced anti-toxic (tolerant) ability in CO. This work provides a new strategy to develop core-shell structure nanomaterials for electrocatalysis.
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Carbono , Nanopartículas del Metal , Carbono/química , Electrodos , Nanopartículas del Metal/química , Oxidación-Reducción , ProtonesRESUMEN
Constructing efficient and stable bifunctional catalysts is essential to improve the conversion efficiency of overall water splitting (OWS). In this work, 3D porous Ni-Fe sulfide nanosheets supported on nickel foam (Ni-Fe-S/NF) were synthesized by a facile hydrothermal method. The optimized Ni3S2-FeS/NF-2 electrode realized ultra-high efficiency for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). Benefiting from the unique 3D porous nanosheets structure and the strong electronic interactions between Ni3S2 and FeS through component regulation, low overpotentials of 253 and 262 mV are required to drive a current density of 100 mA cm-2 for OER and HER, respectively. Importantly, Ni3S2-FeS/NF-2 bifunctional catalyst only needs 1.55 and 1.75 V at 10 and 100 mA cm-2 respectively and works continuously for at least 100 h. The work thus provides an extraordinary promising catalyst for OWS and can be envisioned of potential for large-scale applications.
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Hidrógeno , Agua , Catálisis , Hidrógeno/química , Oxígeno , Porosidad , Sulfuros , Agua/químicaRESUMEN
It is critical to develop carbon material anodes with high initial Coulombic efficiency and energy density for sodium ion batteries. Herein, a novel mushroom spore with chitin as carbon precursor is first reported for energy storage, and its special porous spherical structure, fine structure and oxygen functional groups can be accurately controlled by carbonization temperature. The hollow porous carbon spheres obtained from mushroom spore at 1400 °C have appropriate porous structure, d002 spacing (0.364 nm), 7.12% oxygen content and ultra-low specific surface area of 5.5 m2 g-1. It could obtain 81.2% initial Coulombic efficiency and has reversible discharge capacity of 411.1 mA h g-1, wherein about 75% (308 mA h g-1) of its total capacity is derived from low-potential plateau (below 0.1 V Na+/Na), and the capacity is 384.5 mA h g-1 after 50 cycles. Furthermore, Density functional theory calculation showed that the residual oxygen functional groups (CO) in carbon materials are beneficial to sodium into graphite-like layers, and graphite-like layers spacing is smaller than the reported unadulterated carbon with 0.37 nm. Therefore, the excellent electrochemical performance and low-cost of natural mushroom spore derived hollow porous carbon spheres provide advantages for sodium ion batteries in large-scale storage devices.
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Carbono , Sodio , Electrodos , Iones , PorosidadRESUMEN
Ammonia oxidation reaction (AOR) via electrocatalysis is one of the most efficient ways of utilizing ammonia (a zero-carbon fuel with high hydrogen content) for renewable energy systems. However, AOR seriously suffers from the slow kinetics, and low durability due to its multi-electron transfer process and the poison of the reaction intermediates (Nads and NOads) to precious metal catalysts. Herein, hyperbranched concave octahedral nanodendrites of PtIrCu (HCOND) with high-index facets of {553}, {331} and {221} were developed for the first time using a solvothermal method. The HCOND possesses PtIr-rich edges and exhibit highly efficient AOR activity and stability in alkaline media, wherein their onset potential is 0.35 V vs.RHE, which is 60 mV and 160 mV lower than that of the PtIrCu nanoparticles (NPs) (0.41 V) and commercial Pt/C (0.51 V), respectively, and its high mass activity of 40.6 A gPtIr-1 at the 0.5 V vs.RHE is 10.3 times, 2.34 times higher than that of commercial Pt/C (3.9 A gPt-1) and PtIrCu NPs (17.3 A gPtIr-1), respectively. In addition, its peak current density (122.9 A gPtIr-1) is only reduced by 17.7% after 2000-cycles accelerated durability test. Meanwhile, the performance of PtIrCu HCOND is also better than that of other previously reported morphologies of Pt based catalysts (eg. nanoparticles, nanocubes, nanofilm, nanoflowers). The improvement is critically ascribed to unique advantages of the specific HCOND structure including PtIr rich surface, high-index faceted nanodendrites, strong lattice strain and electronic effects. These characteristics endow the HCOND with great promise to reduce Pt and Ir loading dramatically in the practical application of direct ammonia fuel cells.
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The purpose of the experiment was to study the efficacy of edaravone in enhancing flap viability after ischemia/reperfusion (IR) and its mechanism. Forty-eight adult male SD rats were randomly divided into 3 groups: control group (n=16), IR group (n=16), and edaravone-treated IR group (n=16). An island flap at left lower abdomen (6.0 cm×3.0 cm in size), fed by the superficial epigastric artery and vein, was created in each rat of all the three groups. The arterial blood flow of flaps in IR group and edaravone-treated IR group was blocked for 10 h, and then the blood perfusion was restored. From 15 min before reperfusion, rats in the edaravone-treated IR group were intraperitoneally injected with edaravone (10 mg/kg), once every 12 h, for 3 days. Rats in the IR group and control group were intraperitoneally injected with saline, with the same method and frequency as the rats in the edaravone-treated IR group. In IR group and edaravone-treated IR group, samples of flaps were harvested after reperfusion of the flaps for 24 h. In the control group, samples of flaps were harvested 34 h after creation of the flaps. The content of malondialdehyde (MDA) and activity of superoxide dismutase (SOD) were determined, and changes in organizational structure and infiltration of inflammatory cells were observed by hematoxylin-eosin (HE) staining, apoptotic cells of vascular wall were marked by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay, and the apoptotic rate of cells in vascular wall was calculated. The ultrastructural changes of vascular endothelial cells were observed by transmission electron microscopy (TEM). Seven days after the operation, we calculated the flap viability of each group, and marked vessels of flaps by immunohistochemical staining for calculating the average number of subcutaneous vessels. The results showed that the content of MDA, the number of multicore inflammatory cells and apoptotic rate of cells in vascular wall in the edaravone-treated IR group were significantly lower than those in the IR group. The activity of SOD, flap viability and average number of subcutaneous vessels in the edaravone-treated IR group were significantly higher than those in the IR group. All the differences were statistically significant. The ultrastructure injury of vascular endothelial cells in the edaravone-treated IR group was slighter than that in IR group. It was concluded that edaravone can significantly enhance IR flap viability and protect flap vessels, which is related to scavenging oxygen free radicals, reducing the consumption of SOD, reducing the extent of lipid peroxidation and inflammation, and protecting functional structure of vessels in the early stages of reperfusion.
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Antipirina/análogos & derivados , Supervivencia de Injerto/efectos de los fármacos , Daño por Reperfusión/prevención & control , Colgajos Quirúrgicos/irrigación sanguínea , Colgajos Quirúrgicos/patología , Animales , Antipirina/administración & dosificación , Antipirina/farmacología , Modelos Animales de Enfermedad , Edaravona , Precondicionamiento Isquémico/métodos , Masculino , Malondialdehído/metabolismo , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Daño por Reperfusión/patología , Superóxido Dismutasa/metabolismoRESUMEN
BACKGROUND: The optimal age at which to initiate for auricular reconstruction is controversial. Rib cartilage growth is closely related to age and determines the feasibility and outcomes of auricular reconstruction. We developed a method to guide the timing of auricular reconstruction in children with microtia ranging in age from 5 to 10 years. METHODS: Rib cartilage and the healthy ear were assessed using low-dose multi-slice computed tomography. The lengths of the eighth rib cartilage and the helix of the healthy ear (from the helical crus to the joint of the helix and the earlobe) were measured. Surgery was performed when the two lengths were approximately equal. RESULTS: The preoperative eighth rib measurements significantly correlated with the intraoperative measurements (P < 0.05). From 5 to 10 years of age, eighth rib growth was not linear. In 76 (62.8%) of 121 patients, the eighth rib length was approximately equal to the helix length in the healthy ear; satisfactory outcomes were achieved in these patients. In 18 (14.9%) patients, the eighth rib was slightly shorter than the helix, helix fabrication was accomplished by adjusting the length of the helical crus of stent, and satisfactory outcomes were also achieved. Acceptable outcomes were achieved in 17 (14.0%) patients in whom helix fabrication was accomplished by cartilage splicing. In 9 (7.4%) patients with insufficient rib cartilage length, the operation was delayed. In one (0.8%) patient with insufficient rib cartilage length, which left no cartilage for helix splicing, the result was unsatisfactory. CONCLUSIONS: Eighth rib cartilage growth is variable. Rib cartilage assessment relative to the healthy ear can guide auricular reconstruction and personalize treatment in young patients with microtia.
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Cartílago/diagnóstico por imagen , Microtia Congénita/cirugía , Oído Externo/diagnóstico por imagen , Costillas/diagnóstico por imagen , Factores de Edad , Autoinjertos , Cartílago/crecimiento & desarrollo , Cartílago/trasplante , Niño , Preescolar , Oído Externo/crecimiento & desarrollo , Femenino , Humanos , Masculino , Procedimientos de Cirugía Plástica , Costillas/crecimiento & desarrollo , Tomografía Computarizada por Rayos XRESUMEN
OBJECTIVE: To investigate a method for total reconstruction of auricle. METHODS: 90 patients (101 ears) with congenital microtia underwent two-stage operations for auricular reconstruction. The first stage involved fabrication and grafting of autologous costal cartilage, removing the remnant ear cartilage, embedding the framework into local flap of the mastoid region, transferring the remnant ear lobule flap to link to the inferior framework. The second stage was creating an auriculocephalic sulcus. The reconstruction was performed 4 - 12 months after the first surgery. Skin incision was made 5 mm lateral side of the posterior margin of the auricle. The ear framework carrying a thick ear fascia was separated from the side of the head, the frames of the costal cartilage banked at the first operation were harvested, shaved and transplanted to the posterior wall of the concha with sutures; adjust stand position and angle, so that made the ear shape, position, axis, close to the healthy ear, and auriculocephalic angle was slightly larger than the contralateral ear. Two random flap was designed with superior on the root of the helix and in the inferior-posterior direction of the inferior mastoid area, two flapes were elevated and transplanted to posterior auricular sulcus to cover the grafted cartilage. Skin graft was performed in the remaining raw surface. RESULTS: A total of 90 patients were operated, all of 101 constructed ears achieved satisfied or near satisfied shapes. Five cases of partial skin flap necrosis were caused by pedicle impairment. Exposure of cartilage framework happened in two cases. The auriculocephalic sulcus of four cases diminished after the second stage operation. Three month to two-year follow-up of 67 patients showed that the reconstructed ears were satisfied with the results, including good shapes and steady auriculocephalic angles. CONCLUSIONS: The method is a simple, safe and reliable method for total aural reconstruction.
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Microtia Congénita/cirugía , Pabellón Auricular/cirugía , Procedimientos de Cirugía Plástica/métodos , Cartílago/cirugía , Niño , Cartílago Auricular/cirugía , Humanos , Trasplante de Piel , Colgajos QuirúrgicosRESUMEN
OBJECTIVE: To explore the method of repairing segmental ear helix defect. METHODS: Twenty-one patients with segmental ear helix defect were repaired with post-auricular skin flap. In the first stage operation, ear helix defect was assessed, including the anterior and posterior area defect. According to the defect, post-auricular skin flap was designed and transplanted to repair the defect. Six weeks later, the pedicle of the post-auricular skin flap was cut off, elevated, and folded to form the helix. The secondary defect was directly sutured or repaired with skin graft. RESULTS: Twenty-one patients were treated with this method. In two to 12 months follow-up, all flaps survived and reconstructed ear helices were in good shape. The reconstructed ears were in symmetry to the healthy ones. CONCLUSION: The method is safe and effective for the correction of segmental ear helix defect.
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Pabellón Auricular/cirugía , Procedimientos de Cirugía Plástica/métodos , Trasplante de Piel , Colgajos Quirúrgicos , Adolescente , Adulto , Pabellón Auricular/lesiones , Oído Externo/cirugía , Femenino , Humanos , Masculino , Resultado del Tratamiento , Adulto JovenRESUMEN
OBJECTIVE: To investigate the method for creation of auriculocephalic sulcus. METHODS: The reconstruction was performed 4-12 months after the first surgery. Skin incision was made 5mm posterior to the outer margin of the auricle. The ear framework was elevated with a thick fascia at the deep surface. The costal cartilage banked at the first operation was shaved and transplanted to the deep surface of the concha with sutures. The position and angle of the ear framework was adjusted to be familiar to the healthy ear. The auriculocephalic angle was slightly larger than that in the contralateral ear. Two flaps were designed at the upper and lower area of reconstructed ear and rotated to cover the cartilage. The wound at the donor site was closed with skin graft. RESULTS: A total of 72 patients were treated. All the flaps survived completely. 51 patients were followed up for 3-24 months with satisfactory results. The auriculocephalic sulcus maintained at about 20-30 degree. CONCLUSIONS: It is a simple, safe and reliable method to create a auriculocephalic sulcus with two random skin flaps from mastoid area combined with skin graft.
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Cartílago/trasplante , Pabellón Auricular/cirugía , Deformidades Adquiridas del Oído/cirugía , Trasplante de Piel/métodos , Colgajos Quirúrgicos/trasplante , Adolescente , Procedimientos Quirúrgicos Dermatologicos/métodos , Oído , Fascia , Humanos , Apófisis Mastoides , CostillasRESUMEN
OBJECTIVE: To introduce a modified surgery for total auriculoplasty and the experience in one hundred and forty-six cases (155 ears). METHODS: The procedure was a two-stage operation. The first stage involved fabrication and grafting of a costal cartilage framework. A U-shaped skin incision was made on the posterior edge of the lobule and the remnant ear cartilage was removed completely. The area for the insertion of the cartilage framework was undermined. Skin flaps were sutured after insertion of the cartilage framework. The second-stage surgery was usually performed six months after the first-stage operation. The reconstructed auricle was elevated, and a costal cartilage block was fixed to the posterior part of the auricle. A temporoparietal fascia flap was then used to cover the costal cartilage block. Finally, the posterior aspect of the projected auricle was covered with a spit-thickness skin graft. RESULTS: The incisions healed in one hundred and forty-one patients (150 ears) after the first stage operation. Partial necrosis of the postauricular flap was observed in five cases (5 ears) after the first stage operation, but no exposure or absorption of the cartilage took place. The skin grafts survived in one hundred and thirty-nine cases (147 ears) after the second-stage surgery. Partial necrosis of the skin graft was observed in seven cases (8 ears), but healed after one-week of dressing changes. Ninety-four cases (97 ears) were followed up, but fifty-two cases (58 ears) were lost to follow up. The follow-up at six months to two years showed satisfactory contour and projection of the constructed ears. CONCLUSION: This two-stage surgery is simple and ideal for auricloplasty with few complications.
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Pabellón Auricular/cirugía , Procedimientos de Cirugía Plástica/métodos , Trasplante de Piel/métodos , Colgajos Quirúrgicos , Adolescente , Adulto , Anciano , Niño , Preescolar , Oído Externo/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
OBJECTIVE: To investigate the role of preoperative magnetic resonance tomographic angiography (MRTA) in predicting the clinical outcomes of trigeminal neuralgia (TN) patients following microvascular decompression (MVD). METHODS: Preoperative MRTA imaging was performed on 167 consecutive patients with TN. The characteristics of offending vessels were determined by MRTA prior to MVD. The relationship of neurovascular contact was classified into 3 types: positive, negative, and contralateral positive, which were compared with the surgical findings and clinical outcomes. RESULTS: MRTA showed obvious neurovascular compression in accordance with surgical findings in 144 patients. Among the remaining 23 patients with negative finding on preoperative MRTA images, neurovascular compression (vein alone or in combination with artery) were found in 16, no definite vascular compression in 7. The sensitivity of MRTA on the symptomatic side was therefore 90%, the specificity was 100% in our series. A correlation was found between clinical outcomes and preoperative findings on MRTA. In 144 MRTA-positive patients, 136 achieved "excellent" or "good" outcomes after MVD and were significantly better than the MRTA-negative group (P < .01). The outcomes of patients with a single artery compression were significantly better than those with venous compression, vein in combination with artery compression, or without obvious neurovascular contact (P < .01). Seven of 23 MRTA-negative patients obtained poor outcomes after operation, venous compression were identified intraoperatively in 4 of them, no definite offending vessel was found in 3 patients. CONCLUSIONS: This study suggests that the curative rate of TN following MVD is higher in the MRTA-positive group. Venous compression and no neurovascular contact that were negative on MRTA image are poor prognostic factors for surgical outcome of TN. Thus, preoperative MRTA serves as a useful tool in patient selection and outcome prediction.
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Descompresión Quirúrgica/métodos , Angiografía por Resonancia Magnética/métodos , Microvasos/patología , Microvasos/cirugía , Neuralgia del Trigémino/diagnóstico , Neuralgia del Trigémino/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Humanos , Persona de Mediana Edad , Pronóstico , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Tomografía Óptica/métodos , Resultado del TratamientoRESUMEN
Angiogenesis inhibition has been shown to enhance the therapeutic efficacy of cytotoxic chemotherapy in colorectal cancer. The basis of the contribution of this modality has not been defined fully. To determine the potential role of hypoxia-induced apoptosis, we studied a series of colon cancer cell lines with varying susceptibility to hypoxia. We exposed HT29 and HCT116 colon adenocarcinoma cell lines to sublethal periods of hypoxia three times weekly for 40 exposures, and derived cell lines both more resistant (from HT29) and more sensitive (from HCT116) to hypoxia-induced apoptosis. Both hypoxia-derived cell lines demonstrated more rapid growth than the parental lines when implanted subcutaneously in immunodeficient mice. Treatment of tumor-bearing mice with bevacizumab resulted in depletion of tumor microvasculature, upregulation of Hypoxia-inducible factor-1 alpha (HIF-1alpha), and increased pimonidazole staining, consistent with an anti-angiogenic effect and induction of hypoxia in tumors derived from all cell lines. The proportion of apoptotic cells was increased in all the treated tumors, and was most pronounced in the bevacizumab-treated HCT116-derived cells. The bevacizumab-treated tumors showed growth delay in HT29 and its derivative, and the parental HCT116. In the hypoxia-sensitive HCT116-derived tumors, marked tumor shrinkage and prolonged growth control occurred. Therefore, bevacizumab treatment is an effective inducer of a hypoxic environment, but the resulting cell kill and tumor shrinkage is determined by the susceptibility of the tumor to apoptosis. The induction of apoptosis by hypoxia may contribute to the benefits of such treatment in the clinical setting.
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Inhibidores de la Angiogénesis/farmacología , Anticuerpos Monoclonales/farmacología , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Animales , Anticuerpos Monoclonales Humanizados , Bevacizumab , Hipoxia de la Célula , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/patología , Femenino , Células HCT116 , Células HT29 , Humanos , Ratones , Ratones SCIDRESUMEN
OBJECTIVE: To introduce a method to reconstruct hemifacial atrophy (Romberg's disease). METHODS: Through a temporal incision, the compound grafts of pedicled superficial temporal fascial flap and free dermis-fat were inserted into the cheek to correct soft tissue depression on the face. The dermis-fat was harvested from gluteal crease site. RESULTS: 6 cases were treated with this technique. 3 to 10 months' follow-up showed satisfactory results and few resorption of the compound grafts. CONCLUSIONS: The mentioned technique is simple and reliable in reconstructing bulk defects of the face.
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Tejido Adiposo/trasplante , Dermis/trasplante , Hemiatrofia Facial/cirugía , Procedimientos de Cirugía Plástica/métodos , Tejido Subcutáneo/trasplante , Colgajos Quirúrgicos , Adolescente , Adulto , Edad de Inicio , Niño , Hemiatrofia Facial/epidemiología , Humanos , Adulto JovenRESUMEN
OBJECTIVE: To evaluate a method to repair the defects after the secondary tumor excision and radiation ulcer in the chest, back and axilla. METHODS: Eight patients, with the defects after the secondary tumor excision and the radiation ulcer in the chest, back and axilla, were undergoing the treatment. A "T" shape incision or up-side-down "T" shape incision was designed above the breast or along the inframammary fold below breast, just close to the defect. A split-breast flap was raised above the pectoralis major or deep fascia. The defect was then repaired with a rotating and advancing way. RESULTS: Eight patients were repaired in one stage. Blood circulation of the flaps was abundant except one with distal edge necrosis. The ptosis breast was corrected and the fullness of the chest wall was also achieved. But, the Nipple of the opposite health breast was lost the original position to the lateral or medial. CONCLUSIONS: The above-mentioned technique may be an efficient method to repair the defects after the secondary tumor excision and radiation ulcer in the chest, back and axilla. It is adapt to the old patients whose health is worse, but it is not good for the young patients resulted from the injury breast.
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Procedimientos Quirúrgicos Dermatologicos , Colgajos Quirúrgicos , Procedimientos Quirúrgicos Operativos/métodos , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Axila/cirugía , Dorso/cirugía , Mama/cirugía , Femenino , Humanos , Persona de Mediana Edad , Tórax , Resultado del TratamientoRESUMEN
The dithiolethione oltipraz is a potent chemopreventive agent in preclinical models, and induces the expression of protective enzymes in the colon mucosa and peripheral mononuclear cells of treated human subjects. We investigated the effects of oltipraz on DT-diaphorase expression in HT29 colon adenocarcinoma cells. Following a 24-hr exposure to 100 microM oltipraz, elevated steady-state levels of mRNA for Jun and Fos family members were observed. A nuclear run-on assay showed induction of c-fos and c-jun transcripts at the end of the exposure, peaking at 12 hr after resuspension of cells in drug-free medium. Gel mobility shift analysis revealed a similar time-course of induced nuclear factor binding to an AP-1 probe. Supershift analysis verified the participation of Jun and Fos in the complexes. The redox coactivator Ref-1, a function of which is to enhance AP-1 binding, was induced 5-fold by oltipraz. Immunodepletion of Ref-1 partially inhibited factor binding to the AP-1 probe. Deletion analysis of the DT-diaphorase promoter in a CAT reporter construct revealed that loss of the AP-1 site accounted for approximately 65% of the induction by oltipraz. Mutation of the AP-1 element in a full-length promoter construct yielded similar results. These data suggest the importance of transcriptional activation mediated by AP-1 in the chemopreventive activity of oltipraz, and indicate that novel chemoprevention structures may be selected based upon agonist activity at this locus.
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Liasas de Carbono-Oxígeno/fisiología , ADN-(Sitio Apurínico o Apirimidínico) Liasa , Expresión Génica/efectos de los fármacos , NAD(P)H Deshidrogenasa (Quinona)/genética , Pirazinas/farmacología , Factor de Transcripción AP-1/biosíntesis , Transcripción Genética/efectos de los fármacos , Anticarcinógenos/farmacología , Liasas de Carbono-Oxígeno/metabolismo , Quimioprevención , Células HT29 , Humanos , NAD(P)H Deshidrogenasa (Quinona)/biosíntesis , Regiones Promotoras Genéticas/efectos de los fármacos , Regiones Promotoras Genéticas/fisiología , ARN Mensajero/biosíntesis , ARN Mensajero/efectos de los fármacos , Tionas , TiofenosRESUMEN
Human ovarian cancer cell lines derived from A2780 by stepwise exposure to increasing cisplatin concentrations show progressive resistance to cisplatin. Previous studies have shown increased cellular glutathione and elevated steady-state expression of gamma-glutamylcysteine synthetase (gamma-GCS) and of the transcription factor c-Jun, all in proportion to the level of resistance in the resistant cells. We hypothesized that c-Jun was an important locus of control of the detoxicating enzymes mediating resistance, and that resistance reversal would be achieved by specific inhibition of this mechanism. A2780 (sensitive) and C30 (resistant) cells were treated with a 20-mer c-jun phosphorothioate antisense oligodeoxynucleotide (ISIS 10582, 1 microM), and a decrease in steady-state c-jun mRNA was demonstrated in the resistant cells. The expression of gamma-GCS mRNA was down-regulated and the cellular level of glutathione was decreased in C30 cells. No change in gamma-GCS expression occurred in A2780 cells. Using the microtetrazolium (MTT) cytotoxicity assay, we determined that the c-jun antisense decreased the IC50 value for cisplatin in C30 cells from 18.2 to 3.7 microM, and had a substantially smaller effect in A2780 cells. To determine if c-jun overexpression alone could confer resistance to the sensitive cell line, we transiently transfected A2780 cells with a c-jun expression vector. The transfected cells exhibited a 10.7-fold elevation of glutathione (GSH) content, a 9.2-fold increase in c-Jun protein content, and a 2-fold increase in the IC50 for cisplatin. These data suggest that altered regulation of transcription factor expression contributes to the acquired resistance phenotype in these ovarian cancer cells, and provide a novel potential target for therapeutic intervention.