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1.
Minerva Anestesiol ; 87(10): 1109-1116, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34676743

RESUMO

BACKGROUND: I-gelTM is a second-generation supraglottic airway device with a non-inflatable cuff. In this prospective randomized investigation, we evaluated the effects of two-handed jaw thrust technique on i-gel insertion in anesthetized non-paralyzed patients. METHODS: Seventy-four adult patients were allocated to two groups (N.=37 each). In the jaw thrust group, two-handed jaw thrust technique was applied to facilitate i-gel insertion. In the control group, conventional i-gel insertion was performed. The success rate at the first attempt, air leakage pressure, insertion time, and postoperative sore throat incidence were recorded. RESULTS: The success rate at the first attempt was higher in the jaw thrust group (37 [100%] vs. 31 [84%], difference of 16%, 95% confidence interval for the difference: 1 to 33%, P=0.03). The median air leakage pressure was higher in the jaw thrust group than in the control group (20 [interquartile range 13] vs. 17 [interquartile range 3] cmH2O, difference: 6, 95% confidence interval of the difference: 3 to 8, P<0.01). The mean insertion time was shorter in the jaw thrust group (27±14 vs. 41±29 seconds, difference: 14 seconds, 95% confidence interval of the difference: 3 to 24, P=0.01). The incidence of postoperative sore throat at the postoperative one hour was lower in the jaw thrust group (seven [20%] vs. 15 [41%], difference 22%, 95% confidence interval for the difference: -1 to 42%, P=0.04). CONCLUSIONS: The two-handed jaw thrust technique facilitated i-gel insertion compared to the conventional technique in anesthetized non-paralyzed patients.


Assuntos
Máscaras Laríngeas , Faringite , Adulto , Anestesia Geral , Humanos , Intubação Intratraqueal , Faringite/epidemiologia , Faringite/etiologia , Estudos Prospectivos
2.
Radiat Oncol ; 15(1): 258, 2020 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-33160370

RESUMO

BACKGROUND: This study investigates daily breast geometry and delivered dose to prone-positioned patients undergoing tangential whole breast radiation therapy (WBRT) on an O-ring linear accelerator with 6X flattening filter free mode (6X-FFF), planned with electronic compensation (ECOMP) method. Most practices rely on skin marks or daily planar image matching for prone breast WBRT. This system provides low dose daily CBCT, which was used to study daily robustness of delivered dose parameters for prone-positioned WBRT. METHODS: Eight patients treated with 16-fraction prone-breast WBRT were retrospectively studied. Planning CTs were deformed to daily CBCT to generate daily synthetic CTs, on which delivered dose distributions were calculated. A total of 8 × 16 = 128 synthetic CTs were generated. Consensus ASTRO definition was used to contour Breast PTV Eval for each daily deformed CT. Breast PTV Eval coverage (V90%) and hotspot (V105% and Dmax) were monitored daily to compare prescription dose with daily delivered dose. Various predictors including patient weight, breast width diameter (BWD), and Dice similarity coefficient (DSC) were fit into an analysis of covariance model predicting V90% and V105% deviation from prescribed (ΔV90%, ΔV105%). Statistical significance is indicated with asterisks (* for p < 0.05; ** for p < 0.001). RESULTS: Daily delivered Breast PTV Eval V90% was moderately smaller than prescribed (median ΔV90% = - 0.1%*), while V105% was much larger (median ΔV105% = + 10.1%** or + 92.4 cc**). Patient's weight loss correlated with significantly increased ΔV105% (+ 4.6%/ - 1% weight, R2 = 0.4**) and moderately decreased ΔV90% (- 0.071%/ - 1% wt., R2 = 0.2**). Comprehensive ANCOVA models indicated three factors affect ΔV90% and ΔV105% the most: (1) BWD decrease (- 0.09%* and + 10%**/ - 1 cm respectively), (2) PTV Eval volume decrease (- 0.4%** and + 9%**/ - 100 cc), and for ΔV105% only, (3) the extent of breast deformation (+ 10%**/ - 0.01 DSC). Breast PTV Eval volume also decreased with time (- 2.21*cc/fx), possibly indicating seroma resolution and increase in V105% over time. CONCLUSIONS: Daily CBCT revealed key delivered dose parameters vary significantly for patients undergoing tangential prone breast WBRT planned with ECOMP using 6X-FFF. Patient weight, BWD, and breast shape deformation could be used to predict dosimetric variations from prescribed. Preliminary findings suggest an adaptive plan based on daily CBCT could reduce excessive dose to the breast.


Assuntos
Neoplasias da Mama/radioterapia , Mama/efeitos da radiação , Tomografia Computadorizada de Feixe Cônico/métodos , Aceleradores de Partículas , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Feminino , Humanos , Projetos Piloto , Decúbito Ventral , Dosagem Radioterapêutica
3.
Med Phys ; 47(9): 4363-4371, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32281657

RESUMO

PURPOSE: The purpose of this study was to investigate the feasibility of using fused deposition modeling (FDM) three-dimensional (3D) printer to generate radiation compensators for high-resolution (~1 mm) intensity-modulated radiation therapy (IMRT) for small animal radiation treatment. We propose a novel method incorporating 3D-printed compensator molds filled with NaI powder. METHODS: The inverse planning module of the computational environment for radiotherapy research (CERR) software was adapted to simulate the XRAD-225Cx irradiator, both geometry and kV beam quality (the latter using a phase space file provided for XRAD-225Cx). A nine-field IMRT treatment was created for a scaled-down version of the imaging and radiation oncology core (IROC) Head and Neck IMRT credentialing test, recreated on a 2.2-cm-diameter cylindrical phantom. Optimized fluence maps comprising nine fields and a total of 2564 beamlets were calculated at resolution of 1.25 × 1.25 mm2 . A hollow compensator mold was created (using in-house software and algorithm) for each field using 3D printing with polylactic acid (PLA) filaments. The molds were then packed with sodium iodide powder (NaI, measured density ρNaI  = 2.062 g/cm3 ). The mounted compensator mold thickness was limited to 13.8 mm due to clearance issues with couch collision. At treatment delivery, each compensator was manually mounted to a customized block tray attached to the reference 40 × 40 mm2 collimator. Compensator reproducibility among three repeated 3D-printed molds was measured with Radiochromic EBT2 film. The two-dimensional (2D) dose distributions of the nine fields were compared to calculated 2D doses from CERR using gamma comparisons with distance-to-agreement criteria of 0.5-0.25 mm and dose difference criteria of 3-5%. RESULTS: Good reproducibility of 3D-printed compensator manufacture was observed with mean error of ±0.024 Gy and relative dose error of ±4.2% within the modulated part of the beam. Within the limit of 13.8 mm compensator height, a maximum radiation blocking efficiency of 91.5% was achieved. Per field, about 45.5 g of NaI powder was used. Gamma analysis on each of the nine delivered IMRT fields using radiochromic films resulted in eight of nine treatment fields with >90% pass rate with 5%/0.5 mm tolerances. However, low gamma passing rate of 49-66% (3%/0.25 mm to 5%/0.5 mm) was noted in one field, attributed to fabrication errors resulting in over-filling the mold. The nine-field treatment plan was delivered in under 30 min with no mechanical or collisional issues. CONCLUSIONS: We show the feasibility of high spatial resolution IMRT treatment on a small animal irradiator utilizing 3D-printed compensator shells packed with NaI powder. Using the PLA mold with NaI powder was attractive due to the ease of 3D printing a PLA mold at high geometric resolution and the well-balanced attenuation properties of NaI powders that prevented the mold from becoming too bulky. IMRT fields with 1.25-mm resolution are capable with significant fluence modulation with relative dose accuracy of ±4.2%.


Assuntos
Radioterapia de Intensidade Modulada , Animais , Impressão Tridimensional , Radiometria , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Reprodutibilidade dos Testes
4.
Phys Med Biol ; 64(22): 225017, 2019 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-31505474

RESUMO

RECA (Radiotherapy enhanced with Cherenkov photo-activation) is a proposed treatment where the anti-cancer drug psoralen is photo-activated in situ by UVA (Ultraviolet A, 320-400 nm) Cherenkov light (CL) produced directly by the treatment beam itself. In this study, we develop a UVA-imaging technique to quantify relative UVA CL produced by bulk tissues and other phantoms upon clinical x-ray megavoltage irradiation. UVA CL emission (320-400 nm) was quantified in tissue samples of porcine and poultry and in two kinds of solid waters (SW): brown (Virtual Waters, Standard Imaging, WI) and white (Diagnostic Therapy, CIRS, VA), and in 1% agarose gels variously doped with absorbing dye. Quantification was achieved through cumulative imaging of the samples placed in a dark, light-blocking chamber during irradiation on a Varian 21 EX accelerator. UVA imaging required a specialized high-sensitivity cooled camera equipped with UVA lenses and a filter. At 15 MV, white SW emitted [Formula: see text], [Formula: see text] and [Formula: see text] less UVA than chicken breast, pork loin and pork belly, respectively. Similar under-response was observed at 6 MV. Brown SW had [Formula: see text] less UVA emission than white SW at 15 MV, and negligible emission at 6 MV. Agarose samples (1% by weight) doped with 250 ppm India ink exhibited equivalent UVA CL emission to chicken breast (within 8%). The results confirm that for the same absorbed dose, SW emits less UVA light than the tissue samples, indicating that prior in vitro studies utilizing SW as the CL-generating source may have underestimated the RECA therapeutic effect. Agarose doped with 250 ppm India ink is a convenient tissue-equivalent phantom for further work.


Assuntos
Imagens de Fantasmas , Fenômenos Físicos , Raios Ultravioleta , Terapia por Raios X/instrumentação , Animais , Lentes , Carne
5.
J Surg Res ; 227: 151-157, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29804847

RESUMO

BACKGROUND: It has been previously reported that over 20% of surgical trials will be discontinued prematurely raising ethical and financial concerns. Previous studies have been limited in scope owing to the need for manual review of selected trials. To date, there has been no broad analysis comparing surgical and nonsurgical registered clinical trials. MATERIALS AND METHODS: ClinicalTrials.gov was queried October 7, 2017 for all US trials from 2005 to 2017. Trials were assigned to surgical or nonsurgical groups by automated sorting. The sorting algorithm was validated by comparison with manual assignments made by blinded investigators. Comparisons were made between trial status, funding sources, and trial design. The reasons for discontinuation were examined and tabulated. RESULTS: The database search yielded 82,719 nonsurgical and 5779 surgical trials after automatic assignment. The algorithm for assignments had an overall accuracy of 87.99% and a positive likelihood ratio of 6.09 and negative likelihood ratio of 0.093. Significant differences existed in trial status (nonsurgical versus surgical: completed: 55.51% versus 39.49%, P < 0.001 and discontinued: 11.07% versus 15.97%, P < 0.001). Discontinuation due to poor recruitment was more commonly cited by surgical trials (44.65% versus 34.74% P < 0.001). Industry funding predicted discontinuation for all trials (odds ratio 1.63 P < 0.001) and surgical trials independently (OR 1.25 P = 0.041). Patient enrollment, reporting results, and NIH funding were all protective against discontinuation. CONCLUSIONS: Surgical trials are more likely to prematurely discontinue than nonsurgical trials. Industry funding independently predicts trial discontinuation. Poor recruitment is a major cause of early trial discontinuation for all trials and is more pronounced in surgical trials.


Assuntos
Ensaios Clínicos como Assunto/estatística & dados numéricos , Bases de Dados Factuais/estatística & dados numéricos , Término Precoce de Ensaios Clínicos/estatística & dados numéricos , Seleção de Pacientes , Procedimentos Cirúrgicos Operatórios , Ensaios Clínicos como Assunto/economia , Ensaios Clínicos como Assunto/ética , Término Precoce de Ensaios Clínicos/economia , Término Precoce de Ensaios Clínicos/ética , Feminino , Humanos , Masculino , Estados Unidos
6.
7.
J Cardiovasc Surg (Torino) ; 59(6): 836-843, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29616526

RESUMO

BACKGROUND: Cardiac and cerebrovascular complications are major causes of adverse outcomes following thoracic endovascular aortic repair (TEVAR). The benefits of statins have been established, but little is known about their impact on patients undergoing TEVAR. We investigated whether chronic statin use protected against early postoperative major adverse cardiac and cerebrovascular events (MACCEs) after TEVAR. METHODS: We retrospectively reviewed 211 patients who underwent TEVAR between February 2013 and March 2017 classified into two groups, those with acute aortic syndrome (AAS, N.=79) and those without (non-AAS, N.=132). Patients were subdivided according to preoperative statin therapy for ≥3 months or not. The primary endpoint was 30-day MACCE, defined as myocardial infarction, stroke, arrhythmia, cardiovascular death, or cerebrovascular death. Acute kidney injury (AKI) occurrence within 48 hours was also evaluated. Multivariate logistic regression analysis was performed to identify independent risk factors for MACCEs and AKI. RESULTS: Incidence of MACCEs (1% vs. 11%, P=0.019) was significantly lower in the statin group than in the no-statin group in non-AAS patients. Multivariate logistic regression analysis revealed statin use (odds ratio 0.85, 95% confidence interval 0.01-0.95, P=0.046) as an independent predictor for MACCE in non-AAS patients. The AKI incidence was significantly higher in the statin group than in the no-statin group in AAS patients (44% vs. 15%, P=0.018). CONCLUSIONS: In patients undergoing TEVAR, chronic statin use was associated with reduced 30-day MACCEs in non-AAS patients, but not in AAS patients. It might rather be associated with increased risk of AKI in AAS patients.


Assuntos
Aorta Torácica/cirurgia , Doenças da Aorta/cirurgia , Implante de Prótese Vascular/efeitos adversos , Transtornos Cerebrovasculares/prevenção & controle , Procedimentos Endovasculares/efeitos adversos , Cardiopatias/prevenção & controle , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Doença Aguda , Injúria Renal Aguda/induzido quimicamente , Idoso , Aorta Torácica/diagnóstico por imagem , Doenças da Aorta/diagnóstico por imagem , Doenças da Aorta/mortalidade , Implante de Prótese Vascular/mortalidade , Transtornos Cerebrovasculares/diagnóstico , Transtornos Cerebrovasculares/etiologia , Transtornos Cerebrovasculares/mortalidade , Esquema de Medicação , Procedimentos Endovasculares/mortalidade , Feminino , Cardiopatias/diagnóstico , Cardiopatias/etiologia , Cardiopatias/mortalidade , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Masculino , Pessoa de Meia-Idade , Fatores de Proteção , Estudos Retrospectivos , Fatores de Risco , Síndrome , Resultado do Tratamento
8.
Med Phys ; 45(7): 3315-3320, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29672860

RESUMO

PURPOSE: Cherenkov light during MV radiotherapy has recently found imaging and therapeutic applications but is challenged by relatively low fluence. Our purpose is to investigate the feasibility of increasing Cherenkov light production during MV radiotherapy by increasing photon energy and applying specialized beam-hardening filtration. METHODS: GAMOS 5.0.0, a GEANT4-based framework for Monte Carlo simulations, was used to model standard clinical linear accelerator primary photon beams. The photon source was incident upon a 17.8 cm3 cubic water phantom with a 94 cm source to surface distance. Dose and Cherenkov production was determined at depths of 3-9 cm. Filtration was simulated 15 cm below the photon beam source. Filter materials included aluminum, iron, and copper with thicknesses of 2-20 cm. Histories used depended on the level of attenuation from the filter, ranging from 100 million to 2 billion. Comparing average dose per history also allowed for evaluation of dose-rate reduction for different filters. RESULTS: Overall, increasing photon beam energy is more effective at improving Cherenkov production per unit dose than is filtration, with a standard 18 MV beam yielding 3.3-4.0× more photons than 6 MV. Introducing an aluminum filter into an unfiltered 2400 cGy/min 10 MV beam increases the Cherenkov production by 1.6-1.7×, while maintaining a clinical dose rate of 300 cGy/min, compared to increases of ~1.5× for iron and copper. Aluminum was also more effective than the standard flattening filter, with the increase over the unfiltered beam being 1.4-1.5× (maintaining 600 cGy/min dose rate) vs 1.3-1.4× for the standard flattening filter. Applying a 10 cm aluminum filter to a standard 18 MV, photon beam increased the Cherenkov production per unit dose to 3.9-4.3× beyond that of 6 MV (vs 3.3-4.0× for 18 MV with no aluminum filter). CONCLUSIONS: Through a combination of increasing photon energy and applying specialized beam-hardening filtration, the amount of Cherenkov photons per unit radiotherapy dose can be increased substantially.


Assuntos
Aceleradores de Partículas , Fótons/uso terapêutico , Radioterapia/instrumentação , Radioterapia/métodos , Alumínio , Simulação por Computador , Cobre , Humanos , Ferro , Método de Monte Carlo , Imagens de Fantasmas , Água
9.
Int J Radiat Oncol Biol Phys ; 100(3): 794-801, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29413289

RESUMO

PURPOSE: This work investigates a new approach to enhance radiotherapy through a photo therapeutic agent activated by Cherenkov light produced from the megavoltage photon beam. The process is termed Radiotherapy Enhanced with Cherenkov photo-Activation (RECA). RECA is compatible with various photo-therapeutics, but here we focus on use with psoralen, an ultraviolet activated therapeutic with extensive history of application in superficial and extracorporeal settings. RECA has potential to extend the scope of psoralen treatments beyond superficial to deep seated lesions. METHODS AND MATERIALS: In vitro studies in B16 melanoma and 4T1 murine breast cancer cells were performed to investigate the potential of RT plus RECA versus RT alone for increasing cytotoxicity (local control) and increasing surface expression of major histocompatibility complex I (MHC I). The latter represents potential for immune response amplification (increased antigen presentation), which has been observed in other psoralen therapies. Cytotoxicity assays included luminescence and clonogenics. The MHC I assays were performed using flow cytometry. In addition, Cherenkov light intensity measurements were performed to investigate the possibility of increasing the Cherenkov light intensity per unit dose from clinical megavoltage beams, to maximize psoralen activation. RESULTS: Luminescence assays showed that RECA treatment (2 Gy at 6 MV) increased cytotoxicity by up to 20% and 9.5% for 4T1 and B16 cells, respectively, compared with radiation and psoralen alone (ie, Cherenkov light was blocked). Similarly, flow cytometry revealed median MHC I expression was significantly higher in RECA-treated cells, compared with those receiving radiation and psoralen alone (approximately 450% and 250% at 3 Gy and 6 Gy, respectively, P << .0001). Clonogenic assays of B16 cells at doses of 6 Gy and 12 Gy showed decreases in tumor cell viability of 7% (P = .017) and 36% (P = .006), respectively, when Cherenkov was present. CONCLUSION: This work demonstrates for the first time the potential for photo-activation of psoralen directly in situ, from Cherenkov light generated by a clinical megavoltage treatment beam.


Assuntos
Ficusina/uso terapêutico , Complexo Principal de Histocompatibilidade , Neoplasias Mamárias Animais/radioterapia , Melanoma Experimental/radioterapia , Fármacos Fotossensibilizantes/uso terapêutico , Fototerapia/métodos , Animais , Sobrevivência Celular , Estudos de Viabilidade , Feminino , Medições Luminescentes/métodos , Neoplasias Mamárias Animais/imunologia , Neoplasias Mamárias Animais/metabolismo , Melanoma Experimental/imunologia , Melanoma Experimental/metabolismo , Camundongos , Radioterapia/métodos
10.
Med Phys ; 44(11): 6008-6017, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28837234

RESUMO

PURPOSE: To develop and validate three-dimensional (3D) conformal hippocampal sparing whole-brain radiation therapy (HA-WBRT) for Wistar rats utilizing precision 3D-printed immobilization and micro-blocks. This technique paves the way for future preclinical studies investigating brain treatments that reduce neurotoxicity. METHODS AND MATERIALS: A novel preclinical treatment planning and delivery process was developed to enable precision 3D conformal treatment and hippocampal avoidance capability for the Xrad 225cx small animal irradiator. A range of conformal avoidance plans were evaluated consisting of equiangularly spaced coplanar axial beams, with plans containing 2, 4, 7, and 8 fields. The hippocampal sparing and coverage of these plans were investigated through Monte Carlo dose calculation (SmART-Plan Xrad 225cx planning system). Treatment delivery was implemented through a novel process where hippocampal block shapes were computer generated from an MRI rat atlas which was registered to on-board cone beam CT of the rat in treatment position. The blocks were 3D printed with a tungsten-doped filament at lateral resolution of 80 µm. Precision immobilization was achieved utilizing a 3D-printed support system which enabled angled positioning of the rat head in supine position and bite block to improve coverage of the central diencephalon. Treatment delivery was verified on rodent-morphic Presage® 3D dosimeters optically scanned at 0.2-mm isotropic resolution. Biological verification of hippocampal avoidance was performed with immunohistologic staining. RESULTS: All simulated plans spared the hippocampus while delivering high dose to the brain (22.5-26.2 Gy mean dose to brain at mean hippocampal dose of 7 Gy). No significant improvement in hippocampal sparing was observed by adding beams beyond four fields. Dosimetric sparing of hippocampal region of the four-field plan was verified with the Presage® dosimeter (mean dose = 9.6 Gy, D100% = 7.1 Gy). Simulation and dosimeter match at distance-to-agreement of 2 mm and dose difference of ±3% at 91.7% gamma passing rate (passing criteria of γ < 1). Agreement is less at 1 mm and ±5% at 69.0% gamma passing rate. The four-field plan was further validated with immunohistochemistry and showed a significant reduction in DNA double-strand breaks within the spared region compared with whole-brain irradiated groups (P = 0.021). However, coverage of the whole brain was low at 48.5-57.8% of the volume receiving 30Gy at 7Gy mean hippocampal dose in simulation and 46.7-52.5% in dosimetric measurements. This can be attributed to the shape of the rat hippocampus and the inability of treatment platform to employ non-coplanar beams. CONCLUSION: A novel approach for conformal microradiation therapy using 3D-printing technology was developed, implemented, and validated. A workflow was developed to generate accurate 3D-printed blocks from registered high-resolution rat MRI atlas structures. Although hippocampus was spared with this technique, whole-brain target coverage was suboptimal, indicating that non-coplanar beams and IMRT capability may be required to meet stringent dose criteria associated with current human RTOG trials.


Assuntos
Hipocampo/efeitos da radiação , Órgãos em Risco/efeitos da radiação , Radioterapia Conformacional/efeitos adversos , Radioterapia Conformacional/métodos , Animais , Neoplasias Encefálicas/radioterapia , Impressão Tridimensional , Radiometria , Planejamento da Radioterapia Assistida por Computador , Ratos , Ratos Wistar
11.
Mod Pathol ; 29(2): 194-208, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26743476

RESUMO

Intestinal metaplasia in gastric mucosa is considered a preneoplastic lesion that progresses to gastric cancer. However, the molecular networks underlying this lesion formation are largely unknown. NKX6.3 is known to be an important regulator in gastric mucosal epithelial differentiation. In this study, we characterized the effects of NKX6.3 that may contribute to gastric intestinal metaplasia. NKX6.3 expression was significantly reduced in gastric mucosae with intestinal metaplasia. The mRNA expression levels of both NKX6.3 and CDX2 predicted the intestinal metaplasia risk, with an area under the receiver operating characteristic curve value of 0.9414 and 0.9971, respectively. Notably, the NKX6.3 expression level was positively and inversely correlated with SOX2 and CDX2, respectively. In stable AGS(NKX6.3) and MKN1(NKX6.3) cells, NKX6.3 regulated the expression of CDX2 and SOX2 by directly binding to the promoter regions of both genes. Nuclear NKX6.3 expression was detected only in gastric epithelial cells without intestinal metaplasia. Furthermore, NKX6.3-induced TWSG1 bound to BMP4 and inhibited BMP4-binding activity to BMPR-II. These data suggest that NKX6.3 might function as a master regulator of gastric differentiation by affecting SOX2 and CDX2 expression and the NKX6.3 inactivation may result in intestinal metaplasia in gastric epithelial cells.


Assuntos
Transdiferenciação Celular , Transformação Celular Neoplásica/genética , Inativação Gênica , Proteínas de Homeodomínio/genética , Lesões Pré-Cancerosas/genética , Fatores de Transcrição SOXB1/genética , Neoplasias Gástricas/genética , Fatores de Transcrição/genética , Animais , Antígenos de Bactérias/genética , Antígenos de Bactérias/metabolismo , Área Sob a Curva , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Sítios de Ligação , Proteína Morfogenética Óssea 4/genética , Proteína Morfogenética Óssea 4/metabolismo , Fator de Transcrição CDX2 , Linhagem Celular Tumoral , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Modelos Animais de Doenças , Feminino , Mucosa Gástrica/metabolismo , Mucosa Gástrica/microbiologia , Mucosa Gástrica/patologia , Regulação Neoplásica da Expressão Gênica , Predisposição Genética para Doença , Infecções por Helicobacter/genética , Infecções por Helicobacter/metabolismo , Infecções por Helicobacter/patologia , Helicobacter pylori/genética , Helicobacter pylori/metabolismo , Proteínas de Homeodomínio/metabolismo , Humanos , Metaplasia , Camundongos Endogâmicos C57BL , Fenótipo , Lesões Pré-Cancerosas/metabolismo , Lesões Pré-Cancerosas/microbiologia , Lesões Pré-Cancerosas/patologia , Regiões Promotoras Genéticas , Proteínas/genética , Proteínas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Curva ROC , Medição de Risco , Fatores de Risco , Fatores de Transcrição SOXB1/metabolismo , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/microbiologia , Neoplasias Gástricas/patologia , Fatores de Transcrição/metabolismo , Transfecção
12.
J Appl Physiol (1985) ; 117(6): 577-85, 2014 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-25038105

RESUMO

Although xenon is classically taught to be a "perfusion-limited" gas, (129)Xe in its hyperpolarized (HP) form, when detected by magnetic resonance (MR), can probe diffusion limitation. Inhaled HP (129)Xe diffuses across the pulmonary blood-gas barrier, and, depending on its tissue environment, shifts its resonant frequency relative to the gas-phase reference (0 ppm) by 198 ppm in tissue/plasma barrier and 217 ppm in red blood cells (RBCs). In this work, we hypothesized that in patients with idiopathic pulmonary fibrosis (IPF), the ratio of (129)Xe spectroscopic signal in the RBCs vs. barrier would diminish as diffusion-limitation delayed replenishment of (129)Xe magnetization in RBCs. To test this hypothesis, (129)Xe spectra were acquired in 6 IPF subjects as well as 11 healthy volunteers to establish a normal range. The RBC:barrier ratio was 0.55 ± 0.13 in healthy volunteers but was 3.3-fold lower in IPF subjects (0.16 ± 0.03, P = 0.0002). This was caused by a 52% reduction in the RBC signal (P = 0.02) and a 58% increase in the barrier signal (P = 0.01). Furthermore, the RBC:barrier ratio strongly correlated with lung diffusing capacity for carbon monoxide (DLCO) (r = 0.89, P < 0.0001). It exhibited a moderate interscan variability (8.25%), and in healthy volunteers it decreased with greater lung inflation (r = -0.78, P = 0.005). This spectroscopic technique provides a noninvasive, global probe of diffusion limitation and gas-transfer impairment and forms the basis for developing 3D MR imaging of gas exchange.


Assuntos
Fibrose Pulmonar/patologia , Isótopos de Xenônio , Adulto , Idoso , Idoso de 80 Anos ou mais , Monóxido de Carbono/metabolismo , Eritrócitos/metabolismo , Feminino , Voluntários Saudáveis , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Perfusão , Capacidade de Difusão Pulmonar , Fibrose Pulmonar/fisiopatologia , Reprodutibilidade dos Testes , Testes de Função Respiratória , Adulto Jovem
13.
FEBS J ; 281(3): 851-61, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24616922

RESUMO

Histone deacetylase 2 (HDAC2) is aberrantly regulated and plays a pivotal role in the development of hepatocellular carcinoma (HCC) through regulation of cell-cycle components at the transcriptional level, but the underlying mechanism leading to oncogenic HDAC2 remains unknown. In this study, we show that expression of CK2α (casein kinase II α subunit) was up-regulated in a large cohort of human HCC patients, and that high expression of CK2α was significantly associated with poor prognosis of HCC patients in terms of five-year overall survival. It was also found that CK2α over-expression positively correlated with HDAC2 over-expression in a subset of HCCs. We observed that treatment with epidermal growth factor (EGF) elicited an increase in CK2α expression and Akt phosphorylation, causing induction of HDAC2 expression in liver cancer cells. It was also observed that ectopic expression of dominant-negative CK2α blocked EGF-induced HDAC2 expression, and that ectopic CK2α expression attenuated the suppressive effect of Akt knockdown on HDAC2 expression in liver cancer cells. Targeted disruption of CK2α influenced the cell cycle, causing a significant increase in the number of liver cancer cells remaining in G2/M phase, and suppressed growth via repression of Cdc25c and cyclin B in liver cancer cells. Taken together, our findings suggest the oncogenic potential of CK2α in liver tumorigenesis. Furthermore, a regulatory mechanism for HDAC2 expression is proposed whereby EGF induces transcriptional activation of HDAC2 by CK2α/Akt activation in liver cancer cells. Therefore, this makes CK2α a promising target in cancer therapy.


Assuntos
Carcinogênese , Fator de Crescimento Epidérmico/metabolismo , Receptores ErbB/agonistas , Regulação Neoplásica da Expressão Gênica , Histona Desacetilase 2/metabolismo , Neoplasias Hepáticas/metabolismo , Carcinoma Hepatocelular/metabolismo , Caseína Quinase II/antagonistas & inibidores , Caseína Quinase II/genética , Caseína Quinase II/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Estudos de Coortes , Receptores ErbB/metabolismo , Histona Desacetilase 2/genética , Humanos , Fígado/metabolismo , Proteínas Mutantes/antagonistas & inibidores , Proteínas Mutantes/metabolismo , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Fosforilação , Processamento de Proteína Pós-Traducional , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Transdução de Sinais , Análise de Sobrevida
14.
Clin Oral Implants Res ; 25(6): 714-22, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23418816

RESUMO

OBJECTIVE: This study aimed to investigate the influence of titanium surface-etched microgrooves and ridges on the time-dependent expression of osteoblast marker genes and proteins of human primary cells undergoing osteoblast differentiation. MATERIALS AND METHODS: Fifteen-, 30-, and 60-µm wide, and 3.5- and 10-µm deep-etched microgrooves and ridges were fabricated on titanium substrata using photolithography and subsequent acid etching, and were used as the experimental groups (E15/3.5, E30/10, and E60/10), whereas the smooth and acid-etched titanium were used as the control (NE0 and E0). Time-dependent mRNA and protein expression of type I collagen α1, alkaline phosphatase, runt-related transcription factor 2, osterix, osteocalcin, osteopontin, bone sialoprotein II, and osteonectin after 7, 14, 21, and 28 days of osteogenic culture was analyzed using quantitative real-time PCR, RT-PCR, western blotting, and protein quantitation. Student's t-test, one-way analysis of variance, and Pearson's correlation analysis were used for statistics. RESULTS: Etched microgrooves and ridges induced significantly lower levels of type I collagen α1 gene expression at day 14, and an extreme increase in osteopontin gene expression at days 21 and 28 compared with smooth control. However, the expression levels of the other osteoblast marker genes and proteins analyzed in this study correspond with previously reported expression patterns of cells on variously modified titanium surfaces during osteoblast differentiation and bone formation. CONCLUSION: This study indicates that etched microgrooves and ridges on titanium substrata induce both typical and unique time-dependent expression patterns of the osteoblast marker genes and proteins analyzed in this study.


Assuntos
Expressão Gênica , Osteoblastos/metabolismo , Titânio , Condicionamento Ácido do Dente , Biomarcadores/metabolismo , Western Blotting , Diferenciação Celular , Células Cultivadas , Colágeno/metabolismo , Humanos , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Propriedades de Superfície , Fatores de Tempo
15.
PLoS One ; 8(11): e78728, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24244348

RESUMO

Glioblastoma (GBM) is the most aggressive, neurologically destructive and deadly tumor of the central nervous system (CNS). In GBM, the transcription factors NF-κB and STAT3 are aberrantly activated and associated with tumor cell proliferation, survival, invasion and chemoresistance. In addition, common activators of NF-κB and STAT3, including TNF-α and IL-6, respectively, are abundantly expressed in GBM tumors. Herein, we sought to elucidate the signaling crosstalk that occurs between the NF-κB and STAT3 pathways in GBM tumors. Using cultured GBM cell lines as well as primary human GBM xenografts, we elucidated the signaling crosstalk between the NF-κB and STAT3 pathways utilizing approaches that either a) reduce NF-κB p65 expression, b) inhibit NF-κB activation, c) interfere with IL-6 signaling, or d) inhibit STAT3 activation. Using the clinically relevant human GBM xenograft model, we assessed the efficacy of inhibiting NF-κB and/or STAT3 alone or in combination in mice bearing intracranial xenograft tumors in vivo. We demonstrate that TNF-α-induced activation of NF-κB is sufficient to induce IL-6 expression, activate STAT3, and elevate STAT3 target gene expression in GBM cell lines and human GBM xenografts in vitro. Moreover, the combined inhibition of NF-κB and STAT3 signaling significantly increases survival of mice bearing intracranial tumors. We propose that in GBM, the activation of NF-κB ensures subsequent STAT3 activation through the expression of IL-6. These data verify that pharmacological interventions to effectively inhibit the activity of both NF-κB and STAT3 transcription factors must be used in order to reduce glioma size and aggressiveness.


Assuntos
Glioblastoma/metabolismo , Interleucina-6/biossíntese , NF-kappa B/metabolismo , Proteínas de Neoplasias/metabolismo , Fator de Transcrição STAT3/metabolismo , Animais , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , Glioblastoma/patologia , Glioblastoma/terapia , Xenoenxertos , Humanos , Interleucina-6/genética , Camundongos , Camundongos Nus , NF-kappa B/genética , Proteínas de Neoplasias/genética , Transplante de Neoplasias , Fator de Transcrição STAT3/genética
16.
Mol Cancer Res ; 11(5): 494-505, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23386688

RESUMO

Glioblastoma tumors are characterized by their invasiveness and resistance to therapies. The transcription factor signal transducer and activator of transcription 3 (STAT3) was recently identified as a master transcriptional regulator in the mesenchymal subtype of glioblastoma (GBM), which has generated an increased interest in targeting STAT3. We have evaluated more closely the mechanism of action of one particular STAT3 inhibitor, JSI-124 (cucurbitacin I). In this study, we confirmed that JSI-124 inhibits both constitutive and stimulus-induced Janus kinase 2 (JAK2) and STAT3 phosphorylation, and decreases cell proliferation while inducing apoptosis in cultured GBM cells. However, we discovered that before the inhibition of STAT3, JSI-124 activates the nuclear factor-κB (NF-κB) pathway, via NF-κB p65 phosphorylation and nuclear translocation. In addition, JSI-124 treatment induces the expression of IL-6, IL-8, and suppressor of cytokine signaling (SOCS3) mRNA, which leads to a corresponding increase in IL-6, IL-8, and SOCS3 protein expression. Moreover, the NF-κB-driven SOCS3 expression acts as a negative regulator of STAT3, abrogating any subsequent STAT3 activation and provides a mechanism of STAT3 inhibition after JSI-124 treatment. Chromatin immunoprecipitation analysis confirms that NF-κB p65 in addition to other activating cofactors are found at the promoters of IL-6, IL-8, and SOCS3 after JSI-124 treatment. Using pharmacological inhibition of NF-κB and inducible knockdown of NF-κB p65, we found that JSI-124-induced expression of IL-6, IL-8, and SOCS3 was significantly inhibited, showing an NF-κB-dependent mechanism. Our data indicate that although JSI-124 may show potential antitumor effects through inhibition of STAT3, other off-target proinflammatory pathways are activated, emphasizing that more careful and thorough preclinical investigations must be implemented to prevent potential harmful effects.


Assuntos
Glioblastoma/tratamento farmacológico , NF-kappa B/metabolismo , Fator de Transcrição STAT3/antagonistas & inibidores , Triterpenos/farmacologia , Processos de Crescimento Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Técnicas de Silenciamento de Genes , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Janus Quinase 2/antagonistas & inibidores , Janus Quinase 2/metabolismo , Fosforilação , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Transcrição RelA/deficiência , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/metabolismo
17.
J Neurooncol ; 102(3): 367-81, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21279667

RESUMO

Malignant gliomas are diffusively infiltrative and remain among the deadliest of all cancers. NF-κB is a transcription factor that mediates cell growth, migration and invasion, angiogenesis and resistance to apoptosis. Normally, the activity of NF-κB is tightly regulated by numerous mechanisms. However, in many cancers, NF-κB is constitutively activated and may function as a tumor promoter. Herein, we show that in gliomas, NF-κB is constitutively activated and the levels of cIAP2, Bcl-2, Bcl-xL and Survivin are elevated. These genes are regulated by NF-κB and can inhibit apoptosis. To understand the potential role of NF-κB p65 in suppressing apoptosis, we generated human glioma cell lines that inducibly express shRNA molecules specific for p65. We demonstrate that in the absence of p65, TNF-α induced cIAP2 expression is significantly reduced while the levels of Bcl-2, Bcl-xL and Survivin are not affected. These data suggest that of these genes, only cIAP2 is a direct target of p65, which was confirmed using RT-PCR and chromatin immunoprecipitation (ChIP) assays. By reducing the levels of p65 and/or cIAP2 levels, we demonstrate that the levels of RIP poly-ubiquitination are reduced, and that p65-deficient glioma cells are more sensitive to the cytotoxic effects of TNF-α. Specifically, in the presence of TNF-α glioma cells lacking p65 and/or cIAP2 showed cellular proliferation defects and underwent cell death. These data suggest that NF-κB and/or cIAP2 may be therapeutically relevant targets for the treatment of malignant gliomas.


Assuntos
Neoplasias Encefálicas/patologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioma/patologia , Proteínas Inibidoras de Apoptose/metabolismo , Fator de Transcrição RelA/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Proteína 3 com Repetições IAP de Baculovírus , Caspases/metabolismo , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Imunoprecipitação da Cromatina/métodos , Humanos , Fatores de Tempo , Ubiquitina-Proteína Ligases
18.
J Gambl Stud ; 24(2): 193-205, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18204964

RESUMO

GOAL: This analysis was undertaken to assess the demographic and mental health characteristics of "normal" or non-problem gamblers versus non-gamblers in a representative community sample. SAMPLE STUDY: participants consisted of 557 North Central American Indian veterans. DATA COLLECTION: included a demographic and trauma questionnaire, a computer-based Diagnostic Interview Schedule for DSM-III-R, and a treatment history algorithm. FINDINGS: Univariate analyses revealed that gamblers had greater social competence (i.e., higher education, living with a spouse) and higher lifetime psychiatric morbidity. Binary regression analysis revealed that, compared to non-gamblers, gamblers were older, more highly educated, and more apt to be married. More gamblers showed evidence for lifetime risk-taking as evidenced by Antisocial Personality Disorder and Tobacco Dependence. CONCLUSIONS: Social achievement and disposable income function as prerequisites for "normal" gambling in this population, although "externalizing" or "risk-taking" disorders also serve as independent contributors to at least some gambling. The increased rate of "internalizing" or emotional disorders are only indirectly related to gambling, perhaps through increasing age or through the "externalizing" disorders.


Assuntos
Transtornos Disruptivos, de Controle do Impulso e da Conduta/epidemiologia , Jogo de Azar/psicologia , Indígenas Norte-Americanos/estatística & dados numéricos , Transtornos Mentais/epidemiologia , Saúde Mental , Veteranos/estatística & dados numéricos , Idoso , Alcoolismo/epidemiologia , Ansiedade/epidemiologia , Comorbidade , Depressão/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Assunção de Riscos , Inquéritos e Questionários , Tabagismo/epidemiologia , Estados Unidos
19.
Dig Dis Sci ; 52(10): 2751-6, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17393317

RESUMO

Several lines of evidence indicate that, together with deregulated growth, alteration of apoptosis plays a pivotal role in tumorigenesis. PUMA, a pro-apoptotic member of Bcl-2 family, mediates p53-dependent and -independent apoptosis. BAD is also a pro-apoptotic Bcl-2 family member and phosphorylation of BAD protein inhibits the pro-apoptosis function of BAD. To see whether the alteration of protein expressions of PUMA and phospho-BAD (p-BAD) are characteristics of human colorectal cancers, we analyzed the expression of these proteins in 103 colorectal carcinomas by immunohistochemistry. Also, we analyzed the mutation of the Bcl-2 homology 3 (BH3) domain of PUMA gene, an important domain in the apoptosis function of PUMA, by single-strand conformation polymorphism (SSCP) in 98 colorectal carcinomas. p-BAD immunostaining was detected in 62 cases (60.1%) of the 103 carcinomas, whereas it was not detected in the normal colonic mucosal epithelial cells. PUMA protein expression was detected in both cancer cells and normal mucosal cells in all of the 103 cases. However, the cancer cells showed higher intensities of PUMA immunostaining than the normal cells of the same patients in 50.4% of the cases. There was no association of the p-BAD expression with the PUMA expression. The mutational analysis revealed no PUMA BH3 domain mutation in the cancers. Our data indicated that expressions of both PUMA and p-BAD were increased in the colorectal cancer cells, and suggested that the increased expression of these proteins in malignant colorectal epithelial cells compared to the normal mucosal epithelial cells may possibly alter the cell death regulation during colorectal tumorigenesis.


Assuntos
Adenocarcinoma/genética , Proteínas Reguladoras de Apoptose/genética , Neoplasias Colorretais/genética , DNA de Neoplasias/genética , Regulação Neoplásica da Expressão Gênica , Proteínas Proto-Oncogênicas/genética , Proteína de Morte Celular Associada a bcl/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Apoptose , Proteínas Reguladoras de Apoptose/biossíntese , Biomarcadores Tumorais/biossíntese , Biomarcadores Tumorais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Progressão da Doença , Humanos , Imuno-Histoquímica , Mutação , Reação em Cadeia da Polimerase , Proteínas Proto-Oncogênicas/biossíntese , Proteína de Morte Celular Associada a bcl/biossíntese
20.
Community Ment Health J ; 42(6): 537-53, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16897410

RESUMO

This community survey studied remission from pathological gambling (PG) among American Indian (AI) and Hispanic American (HA) veterans. Remission was defined as having a lifetime diagnosis of PG, but no gambling symptoms in the last year. Sample consisted of 1624 AI and Hispanic veterans. Instruments included demographic data, the computer-based algorithmic Quick Diagnostic Interview Schedule Symptom, and three symptom checklists, one each for substance related problems (MAST/AD), anxiety and depressive symptoms (BSI-57), and combat-related post-trauma symptoms (PCL/M). Remission was associated with absence of a current Axis 1 diagnosis, especially absence of a current post-traumatic stress disorder.


Assuntos
Transtornos Disruptivos, de Controle do Impulso e da Conduta/diagnóstico , Jogo de Azar/psicologia , Hispânico ou Latino/psicologia , Indígenas Norte-Americanos/psicologia , Veteranos/psicologia , Adulto , Idoso , Transtornos de Ansiedade/diagnóstico , Transtornos de Ansiedade/psicologia , Transtornos de Ansiedade/terapia , Distúrbios de Guerra/diagnóstico , Distúrbios de Guerra/psicologia , Distúrbios de Guerra/terapia , Comorbidade , Transtorno Depressivo/diagnóstico , Transtorno Depressivo/psicologia , Transtorno Depressivo/terapia , Transtornos Disruptivos, de Controle do Impulso e da Conduta/psicologia , Transtornos Disruptivos, de Controle do Impulso e da Conduta/terapia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Meio-Oeste dos Estados Unidos , Grupos de Autoajuda , Sudoeste dos Estados Unidos , Resultado do Tratamento
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