Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 14 de 14
Filtrar
Filtros adicionais











Tipo de estudo
Intervalo de ano
1.
ACS Appl Mater Interfaces ; 11(14): 13652-13664, 2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30900457

RESUMO

Owing to its mechanical performance, thermal stability, and size effects, single or few-layer black phosphorus (BP) has the potential to prepare the polymer nanocomposites as a candidate of nanoadditives, similar to graphene. The step to realize the scalable exfoliation of single or few-layer BP nanosheets is crucial to BP applications. Herein, we utilized a facile, green, and scalable electrochemical strategy for generating cobaltous phytate-functionalized BP nanosheets (BP-EC-Exf) wherein the BP crystal served as the cathode and phytic acid served as a modifier and an electrolyte simultaneously. Moreover, high-performance polyurethane acrylate/BP-EC-Exf (PUA/BP-EC) nanocomposites are easily prepared by a convenient UV-curable strategy for the first time. Significantly, the conclusion of introducing BP-EC-Exf into the PUA matrix resulted in enhancement in mechanical properties of PUA in terms of the tensile strength (increased by 59.8%) and tensile fracture strain (increased by 88.1%), in the distinct improvement in flame retardancy of PUA in terms of the decreased peak heat release rate (reduced by 44.5%) and total heat release (decreased by 34.5%), and in lower intensities of pyrolysis products including toxic CO. Moreover, it was confirmed by X-ray diffraction and Raman spectra that the air stability of PUA/BP-EC nanocomposites was maintained after exposure to environmental conditions for 4 months. The air-stable BP nanosheets, which were wrapped and embedded in the PUA matrix, can achieve the isolation and protection effect. This modified electrochemical method toward the simultaneous exfoliation and functionalization of BP nanosheets provides an efficient approach for fabricating BP-polymer-based nanocomposites.

2.
Chemistry ; 24(56): 15019-15025, 2018 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-29998593

RESUMO

Photocatalysis is an efficient approach to degrade hydrogen sulfide (H2 S) and titanium dioxide (TiO2 ) is commonly used as a catalyst for H2 S degradation. However, the low separation rate of photoinduced carriers and low gas adsorption ability of TiO2 limit its H2 S photocatalytic decomposition rate. In this paper, single-crystalline TiO2 nanowires are assembled on one-dimensional carbon nanofibers (CNFs) and a tunable metal-organic framework (MOF) coating is fabricated on the surface of the TiO2 nanowires using a versatile step-by-step self-assembly strategy. The excellent photocatalytic properties of the resulting membrane originate from the ability of the CNFs to rapidly transport charge carriers and the high and regenerable H2 S adsorption ability of the MOF. The photocatalytic mechanism of the as-prepared material was also discussed. Therefore, this work provides a promising method to improve the photocatalytic performance of H2 S degradation.

3.
Carbohydr Polym ; 166: 131-138, 2017 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-28385215

RESUMO

Green polyelectrolytes including chitosan (CS), phytic acid (PA) and oxidized sodium alginate (OSA) were deposited on polyamide 66 (PA66) fabrics in a quadralayer (QL) fashion like (CS-PA-CS-OSA)n (where "n" denotes the number of quadra layers) via layer-by-layer (LbL) assembly to improve the flame retardant property. In the vertical burning test, the PA66 fabric with 10 and 15 QL depositions could stop the melt-dripping. Cone calorimetry results showed that a maximum reduction (24%) in the peak heat release rate was achieved for the PA66 fabric with 5 QL depositions. Thermogravimetric analysis indicated that the presence of the polyelectrolytes catalyzed the degradation pathway of virgin PA66 fabric where the initial decomposition temperature was reduced and the char yield was enhanced for all the coated fabrics significantly. Moreover, UV-vis spectroscopy demonstrated that the use of OSA could improve the durability of such a multilayered nanocoating.

4.
Cancer Biomark ; 19(1): 27-34, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28269749

RESUMO

BACKGROUND: Aurora A kinase is frequently overexpressed in a variety of tumor types, including the prostate. However, the function of Aurora A in autophagy in prostate cancer has not been investigated. Here, we aimed to study the functioning mechanism and autophagy associated signaling pathways of Aurora A in prostate cancer. METHODS: To investigate the biological function of Aurora A, down-regulation of Aurora A was performed followed by functional testing assays. Immunohistochemistry was used to detect the expression of Aurora A in human prostate cancer specimens. CCK8, Transwell, flow cytometric analysis and measurement of tumor formation in nude mice were performed to test the effects of Aurora A down-regulation in vivo and in vitro. Signaling pathway analysis was performed by using Western blot. Autophagy activity was measured by monitoring the expression levels of LC3-II. RESULTS: Aurora A overexpression was significantly higher in human prostate cancer specimens than in BPH. Furthermore, Aurora A knockdown inhibited the proliferation of prostate cancer cells by suppressing the Akt pathway, indicating that Akt is a novel Aurora A substrate in prostate cancer. Additionally, Aurora A down-regulation prompts autophagy in prostate cancer cells. Most importantly, Aurora A ablation almost fully abrogates tumorigenesis in nude mice, suggesting that Aurora A is a key oncogenic effector in prostate cancer. CONCLUSIONS: Taken together, our data suggest that Aurora-A plays an important role in the suppression of autophagy by inhibiting the phosphorylation of Akt, which in turn prevents autophagy-induced apoptosis in prostate cancer.


Assuntos
Aurora Quinase A/genética , Autofagia/genética , Proliferação de Células/genética , Neoplasias da Próstata/genética , Animais , Apoptose/genética , Linhagem Celular Tumoral , Humanos , Masculino , Camundongos , Proteína Oncogênica v-akt/genética , Fosforilação , Neoplasias da Próstata/patologia , Transdução de Sinais , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Bioact Mater ; 2(2): 53-62, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29744412

RESUMO

In this work, the biodegradable and histocompatibility properties of pure Mg and ZK60 alloy were investigated as new temporary implants for urinary applications. The corrosion mechanism in artificial urine was proposed using electrochemical impedance spectroscopy and potentiodynamic polarization tests. The corrosion potential of pure magnesium and ZK60 alloy were -1820 and -1561 mV, respectively, and the corrosion current densities were 59.66 ± 6.41 and 41.94 ± 0.53 µA cm-2, respectively. The in vitro degradation rates for pure Mg and ZK60 alloy in artificial urine were 0.382 and 1.023 mm/y, respectively, determined from immersion tests. The ZK60 alloy degraded faster than the pure Mg in both artificial urine and in rat bladders (the implants of both samples are ø 3 mm × 5 mm). Histocompatibility evaluations showed good histocompatibility for the pure Mg and ZK60 alloy during the 3 weeks post-implantation in rat bladders, and no harm was observed in the bladder, liver and kidney tissues. The results provide key information on the degradation properties and corrosion mechanism of pure Mg and ZK60 alloy in the urinary system.

6.
World J Gastroenterol ; 22(20): 4958-62, 2016 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-27239122

RESUMO

Abdominal cocoon syndrome (ACS) is a rare cause of intestinal obstruction due to total or partial encapsulation of the small intestine by a fibrocollagenous membrane. Idiopathic ACS with abdominal cryptorchidism and greater omentum hypoplasia is even rarer clinically. We successfully treated a 26-year-old male case of small bowel obstruction with acute peritonitis. He was finally diagnosed with idiopathic ACS with unilateral abdominal cryptorchidism and greater omentum hypoplasia during exploratory laparotomy. He then underwent enterolysis, cryptorchidectomy, and appendectomy. He recovered gradually from the operations and early postoperative inflammatory ileus. There has been no recurrence of intestinal obstruction since the operation, and he is still in follow-up. We analyzed his clinical data and retrospectively reviewed the literature, and our findings may be helpful for the clinical diagnosis and treatment on ACS.


Assuntos
Criptorquidismo/complicações , Obstrução Intestinal/etiologia , Intestino Delgado , Omento/anormalidades , Fibrose Peritoneal/complicações , Adulto , Apendicectomia , Biópsia , Criptorquidismo/diagnóstico , Criptorquidismo/cirurgia , Humanos , Ácido Hialurônico/uso terapêutico , Obstrução Intestinal/diagnóstico , Obstrução Intestinal/cirurgia , Intestino Delgado/diagnóstico por imagem , Intestino Delgado/patologia , Intestino Delgado/cirurgia , Masculino , Orquiectomia , Fibrose Peritoneal/diagnóstico , Fibrose Peritoneal/cirurgia , Tomografia Computadorizada por Raios X , Resultado do Tratamento
7.
J Hazard Mater ; 314: 260-269, 2016 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-27136731

RESUMO

A uniform zinc hydroxystannate (ZnHS) microcube was synthesized to reduce toxicity and fire hazards of thermoplastic polyurethane (TPU) composites using ammonium polyphosphate as a flame retardant agent. The structure, morphology and thermal properties of ZnHS were characterized by X-ray diffraction, transmission electron microscopy and thermogravimetric analysis, respectively. Smoke suppression properties and synergistic flame retardant effect of ZnHS on flame retardant TPU composites were intensively investigated by smoke density test, cone calorimeter test, and thermalgravimetric analysis. Thermogravimetric analysis/infrared spectrometry and tube furnace were employed to evaluate the toxic gases (CO, NOx and HCN) of TPU composites. The incorporation of ZnHS into TPU matrix effectively improved the fire safety and restrained the smoke density, which is attributed to that the char residue catalyzed by ZnHS enhanced barrier effect that reduced peak heat release rate, total heat release, smoke particles and organic volatiles during combustion. Furthermore, the ZnHS synergist demonstrated high efficiency in catalytic degradation of the toxic gases, which obviously decreased total volatiled product and toxic volatiles evolved, such as the CO, HCN and NOx, indicating suppressed toxicity of the TPU composites.

8.
Tumour Biol ; 37(4): 5165-70, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26547586

RESUMO

There is increasing evidence suggesting that establishment of sister chromatid cohesion N-acetyltransferase 1 (ESCO1) was involved in tumorigenesis. However, its role in bladder cancer remains unclear. In this study, we aimed to study the clinical correlation and biological significance of ESCO1 in bladder cancer. Our results showed that ESCO1 was significantly over-expressed in bladder cancer tissues compared with that in adjacent normal tissues. And, increased ESCO1 expression was significantly associated with higher grade (P < 0.001), higher tumor stage (P = 0.014), and multifocality (P = 0.042). Kaplan-Meier analysis and Cox proportional hazards model were performed to determine the prognostic significance of ESCO1, and the results showed that ESCO1 is a useful prognostic marker for bladder cancer patients. Moreover, we found that ESCO1 knockdown inhibited the growth, migration, and invasion of bladder cancer cells. In conclusion, our findings indicated that ESCO1 may play an important role in human bladder cancer, and ESCO1 might serve as a novel target and prognosis factor for human bladder cancer.


Assuntos
Acetiltransferases/biossíntese , Biomarcadores Tumorais/biossíntese , Recidiva Local de Neoplasia/genética , Prognóstico , Neoplasias da Bexiga Urinária/genética , Acetiltransferases/genética , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Neoplasias da Bexiga Urinária/patologia
9.
Drug Des Devel Ther ; 9: 5911-23, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26604689

RESUMO

BACKGROUND: PACE4 is a proprotein convertase capable of processing numerous substrates involved in tumor growth, invasion, and metastasis. However, the precise role of PACE4 during prostate cancer cell apoptosis has not been reported. METHODS: In the present study, human prostate cancer cell lines DU145, LNCaP, and PC3 were transfected with PACE4 small interfering (si)RNA to investigate the underlying mechanisms of apoptosis. RESULTS: We revealed that PACE4 siRNA exhibited antitumor activity by inducing apoptosis, as determined by Cell Counting Kit-8 (CCK-8), 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltet-razolium bromide (MTT) assay, cell cycle analysis, Hoechst staining, caspase-3/7 activity, and western blot analysis. In addition, PACE4 siRNA significantly increased the ratio of Bax/Bcl-2, which led to the release of cytochrome c. Moreover, PACE4 siRNA also induced endoplasmic reticulum stress by increasing the expression of GRP78, GRP94, p-PERK, and p-eIF2α. The ratio of Bax/Bcl-2 and GRP78 were also increased in PACE4 gene knockdown prostate cancer cells compared with the control cells. CONCLUSION: These data demonstrate that PACE4 siRNA may exert its antitumor activity through mitochondrial and endoplasmic reticulum stress signaling pathways, indicating it may be a novel therapeutic target for prostate cancer.


Assuntos
Apoptose/genética , Estresse do Retículo Endoplasmático/genética , Pró-Proteína Convertases/genética , Neoplasias da Próstata/patologia , Serina Endopeptidases/genética , Linhagem Celular Tumoral , Citocromos c/metabolismo , Regulação Neoplásica da Expressão Gênica/genética , Técnicas de Silenciamento de Genes , Humanos , Masculino , Mitocôndrias/metabolismo , Neoplasias da Próstata/genética , RNA Interferente Pequeno/administração & dosagem , Transdução de Sinais/genética
10.
Tumour Biol ; 36(8): 6133-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25773392

RESUMO

SOX genes play an important role in a number of developmental processes. The transcription factor SOX11 is one of the members of the SOX family emerging as important transcriptional regulators. The aim of this study was to investigate the role of SOX11 in prostate cancer (PCa) and its expression pattern and clinical significance. The gene expression of SOX11 in human PCa tissues compared with benign prostate hyperplasia (BPH) tissues was detected using real-time quantitative reverse transcriptase-polymerase chain reaction (QRT-PCR) analysis and immunohositochemistry. SOX11 overexpression cell model was used to examine the role of SOX11 in cell growth and metastasis in vitro. The results showed that the positive rate of SOX11 staining was 16.67 % (10/60) in cases of prostatic carcinoma and 81.67 % (49/60) in cases of BPH, and the difference of SOX11 expression between PCa and BPH was statistically significant (P < 0.001). SOX11 mRNA level was lowly expressed in PCa cell lines compared to RWPE-1. SOX11 overexpression suppresses PCa cell migration and invasion. In conclusion, our findings demonstrate that SOX11 could suppress cell proliferation, migration, and invasion of PCa in vitro.


Assuntos
Proliferação de Células/genética , Neoplasias da Próstata/genética , Fatores de Transcrição SOXC/biossíntese , Linhagem Celular Tumoral , Movimento Celular/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Invasividade Neoplásica/genética , Neoplasias da Próstata/patologia , RNA Mensageiro/biossíntese , Fatores de Transcrição SOXC/genética
11.
Int J Clin Exp Med ; 8(10): 19418-23, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26770585

RESUMO

PURPOSE: To evaluate clinical efficacy and safety of two micron laser vaporesection combined with transurethral resection of the prostate (TURP) in treating benign prostatic hyperplasia (BPH). METHODS: In total, 340 BPH patients aged 62-86 years, were treated with two micron laser vaporesection plus TURP. Mean prostatic volume was measured as 38-182 ml. Operative time, intraoperative hemorrhage volume, time of postoperative bladder irrigation, time of indwelling urinary catheter and surgical complications were examined. International Prostate Symptom Score (IPSS), quality of life score (QOL), maximal urinary flow rate (Qmax) and post void residual urine volume (PVR) were analyzed. RESULTS: All cases underwent the surgery successfully. No transurethral resection syndrome was noted. Mean operative time was (72±15) min. Mean intra operative hemorrhage volume was (48.4±13.0) ml. Four patients were transfused with 2 U of suspended red blood cells. Time of postoperative bladder irrigation ranged from 0.5-2.5 d. Time of indwelling urinary catheter was 3-6 d. After removing urinary catheter, mild urinary irritation symptoms were noted in 19 cases. Ten patients developing urinary infection were recovered following anti-infection therapy. One with secondary urethral stenosis was healed after urethral dilatation for three times. Postoperative IPSS, QOL, Qmax and PVR were (6.0±2.0), (2.0±0.2), (18.5±1.6) ml/s and (11.0±4.0) ml, significantly improved compared with preoperative levels (all P<0.05). Fifty eight cases with normal sexual function retained sexual function postoperatively and had no retrograde ejaculation. CONCLUSIONS: Two micron laser vaporesection plus TURP is efficacious and safe in treating BPH with mild lower urinary tract symptoms and perioperative complications.

12.
Urology ; 80(1): e1-2, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22607944

RESUMO

Laparoscopic radical nephrectomy should be executed under the most fundamental principle of early ligature of the renal artery to prevent diffusion of cancerous cells. This is extremely true in the treatment of large renal tumors touching the main renal vasculature. Obviously, the concomitance of a duplicated inferior vena cava (IVC) with associated aberrant tributaries will significantly increase the surgical difficulty and the procedural risk of vascular injury. Herein we describe a transperitoneal left laparoscopic radical nephrectomy for a large hilar left renal tumor in the presence of a duplicated IVC with complicated anomalous tributaries by a transmesocolic approach.


Assuntos
Laparoscopia/métodos , Nefrectomia/métodos , Veia Cava Inferior/anormalidades , Veia Cava Inferior/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade
13.
Urology ; 79(3): 577-83, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22386401

RESUMO

OBJECTIVE: To assess the feasibility, safety, and efficacy of transperitoneal laparoendoscopic single-site (LESS) adrenalectomy and determine whether it shows any objective advantage compared with standard laparoscopy. METHODS: From August 2009 to May 2011, 13 transperitoneal LESS adrenalectomies were performed through a 2-3-cm skin incision using the TriPort access system. This cohort was compared with a contemporary 1:2 matched-pair group of 26 patients undergoing standard laparoscopic adrenalectomy by the same urologist. The perioperative outcomes, including cosmetic satisfaction scores, were statistically analyzed. RESULTS: The 2 groups were comparable with respect to patient demographics, estimated blood loss, and postoperative hospitalization (P > .05). The LESS procedures had a longer mean operative time (148.5 vs 112.9 minutes, P = .032) but a significantly lower postoperative visual analog pain scale score (2.3 vs 3.7, P = .001), fewer patients requiring analgesics (30.8% vs 73.1%, P = .011), and an earlier resumption of oral intake (21.6 vs 26.0 hours, P = .002). The mean length of the scar in the LESS group was much smaller (2.3 vs 5.9 cm, P < .0001) with a statistically significant greater mean cosmetic satisfaction score (9.5 vs 9.1, P = .042). CONCLUSION: The perioperative outcomes of transperitoneal LESS adrenalectomy for small adrenal tumors were comparable to those with the standard laparoscopic approach. It also provides better postoperative pain control, faster recovery of bowel function, and better cosmetic satisfaction than standard laparoscopy, albeit with a longer operative time.


Assuntos
Neoplasias das Glândulas Suprarrenais/cirurgia , Adrenalectomia/métodos , Adrenalectomia/instrumentação , Adulto , Endoscopia/métodos , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
14.
Urology ; 78(2): 469-73, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21664650

RESUMO

OBJECTIVES: To report a case and the surgical techniques of transperitoneal laparoscopic partial nephrectomy (LPN) in a patient with a small left renal mass and an aberrant left-sided inferior vena cava (IVC). METHODS: An otherwise healthy 49-year-old man with a body mass index of 23.1 kg/m(2) was diagnosed with a 5 × 6-cm mass in the left kidney. A transperitoneal LPN was performed in the presence of a left-sided IVC. The procedure was completed using standard laparoscopic instruments. The left renal vein was identified, with the gonadal vein used as an anatomic landmark. Slightly rostral to the location where the renal vein emptied into the left-sided IVC, 2 renal arteries were dissected and clamped individually using laparoscopic bulldog clamps. A standard LPN was then completed. RESULTS: The duration of the surgery was 182 minutes, and there was an estimated blood loss of 100 mL. The warm ischemic time was 31 minutes. The postoperative recovery was uneventful, and the patient was discharged to his home on postoperative day 7. A pathologic examination revealed a renal oxyphilic adenoma, which is a benign lesion. At the follow-up visits that were 1 month and 3 months after surgery, the patient was determined to be clinically healthy. CONCLUSIONS: The anomaly of a left-sided IVC is not an impediment to performing a transperitoneal LPN; however, the correct identification of the anatomical landmarks and the use of meticulous intraoperative techniques are of paramount importance during this procedure.


Assuntos
Neoplasias Renais/complicações , Neoplasias Renais/cirurgia , Laparoscopia , Nefrectomia/métodos , Veia Cava Inferior/anormalidades , Humanos , Masculino , Pessoa de Meia-Idade , Peritônio
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA