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2.
Nature ; 629(8012): 555-560, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38658758

RESUMO

The tokamak approach, utilizing a toroidal magnetic field configuration to confine a hot plasma, is one of the most promising designs for developing reactors that can exploit nuclear fusion to generate electrical energy1,2. To reach the goal of an economical reactor, most tokamak reactor designs3-10 simultaneously require reaching a plasma line-averaged density above an empirical limit-the so-called Greenwald density11-and attaining an energy confinement quality better than the standard high-confinement mode12,13. However, such an operating regime has never been verified in experiments. In addition, a long-standing challenge in the high-confinement mode has been the compatibility between a high-performance core and avoiding large, transient edge perturbations that can cause very high heat loads on the plasma-facing-components in tokamaks. Here we report the demonstration of stable tokamak plasmas with a line-averaged density approximately 20% above the Greenwald density and an energy confinement quality of approximately 50% better than the standard high-confinement mode, which was realized by taking advantage of the enhanced suppression of turbulent transport granted by high density-gradients in the high-poloidal-beta scenario14,15. Furthermore, our experimental results show an integration of very low edge transient perturbations with the high normalized density and confinement core. The operating regime we report supports some critical requirements in many fusion reactor designs all over the world and opens a potential avenue to an operating point for producing economically attractive fusion energy.

3.
Phys Rev Lett ; 131(14): 145101, 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37862644

RESUMO

We report the observation of a set of coherent high frequency electromagnetic fluctuations that leads to a turbulence induced self-regulating phenomenon in the DIII-D high bootstrap current fraction plasma. The fluctuations have frequency of 130-220 kHz, the poloidal wavelength and phase velocity are 16-30 m^{-1} and ∼30 km/s, respectively, in the outboard midplane with the estimated toroidal mode number n∼5-9. The fluctuations are located in the internal transport barrier (ITB) region at large radius and are experimentally validated to be kinetic ballooning modes (KBM). Quasilinear estimation predicts the KBM to be able to drive experimental particle flux and non-negligible thermal flux, suggesting its significant role in regulating the ITB saturation.

4.
Ultrasound Obstet Gynecol ; 60(3): 381-389, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35247287

RESUMO

OBJECTIVE: To evaluate the performance of third-trimester ultrasound for the diagnosis of clinically significant placenta accreta spectrum disorder (PAS) in women with low-lying placenta or placenta previa. METHODS: This was a prospective multicenter study of pregnant women aged ≥ 18 years who were diagnosed with low-lying placenta (< 20 mm from the internal cervical os) or placenta previa (covering the internal cervical os) on ultrasound at ≥ 26 + 0 weeks' gestation, between October 2014 and January 2019. Ultrasound suspicion of PAS was raised in the presence of at least one of these signs on grayscale ultrasound: (1) obliteration of the hypoechogenic space between the uterus and the placenta; (2) interruption of the hyperechogenic interface between the uterine serosa and the bladder wall; (3) abnormal placental lacunae. Histopathological examinations were performed according to a predefined protocol, with pathologists blinded to the ultrasound findings. To assess the ability of ultrasound to detect clinically significant PAS, a composite outcome comprising the need for active management at delivery and histopathological confirmation of PAS was considered the reference standard. PAS was considered to be clinically significant if, in addition to histological confirmation, at least one of these procedures was carried out after delivery: use of hemostatic intrauterine balloon, compressive uterine suture, peripartum hysterectomy, uterine/hypogastric artery ligation or uterine artery embolization. The diagnostic performance of each ultrasound sign for clinically significant PAS was evaluated in all women and in the subgroup who had at least one previous Cesarean section and anterior placenta. Post-test probability was assessed using Fagan nomograms. RESULTS: A total of 568 women underwent transabdominal and transvaginal ultrasound examinations during the study period. Of these, 95 delivered in local hospitals, and placental pathology according to the study protocol was therefore not available. Among the 473 women for whom placental pathology was available, clinically significant PAS was diagnosed in 99 (21%), comprising 36 cases of placenta accreta, 19 of placenta increta and 44 of placenta percreta. The median gestational age at the time of ultrasound assessment was 31.4 (interquartile range, 28.6-34.4) weeks. A normal hypoechogenic space between the uterus and the placenta reduced the post-test probability of clinically significant PAS from 21% to 5% in women with low-lying placenta or placenta previa in the third trimester of pregnancy and from 62% to 9% in the subgroup with previous Cesarean section and anterior placenta. The absence of placental lacunae reduced the post-test probability of clinically significant PAS from 21% to 9% in women with low-lying placenta or placenta previa in the third trimester of pregnancy and from 62% to 36% in the subgroup with previous Cesarean section and anterior placenta. When abnormal placental lacunae were seen on ultrasound, the post-test probability of clinically significant PAS increased from 21% to 59% in the whole cohort and from 62% to 78% in the subgroup with previous Cesarean section and anterior placenta. An interrupted hyperechogenic interface between the uterine serosa and bladder wall increased the post-test probability for clinically significant PAS from 21% to 85% in women with low-lying placenta or placenta previa and from 62% to 88% in the subgroup with previous Cesarean section and anterior placenta. When all three sonographic markers were present, the post-test probability for clinically significant PAS increased from 21% to 89% in the whole cohort and from 62% to 92% in the subgroup with previous Cesarean section and anterior placenta. CONCLUSIONS: Grayscale ultrasound has good diagnostic performance to identify pregnancies at low risk of PAS in a high-risk population of women with low-lying placenta or placenta previa. Ultrasound may be safely used to guide management decisions and concentrate resources on patients with higher risk of clinically significant PAS. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Placenta Acreta , Placenta Prévia , Cesárea , Feminino , Humanos , Placenta/diagnóstico por imagem , Placenta/patologia , Placenta Acreta/diagnóstico por imagem , Placenta Acreta/patologia , Placenta Prévia/diagnóstico por imagem , Placenta Prévia/patologia , Gravidez , Terceiro Trimestre da Gravidez , Diagnóstico Pré-Natal , Estudos Prospectivos , Estudos Retrospectivos , Ultrassonografia Pré-Natal/métodos
5.
Nat Commun ; 12(1): 1365, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33649306

RESUMO

Divertor detachment offers a promising solution to the challenge of plasma-wall interactions for steady-state operation of fusion reactors. Here, we demonstrate the excellent compatibility of actively controlled full divertor detachment with a high-performance (ßN ~ 3, H98 ~ 1.5) core plasma, using high-ßp (poloidal beta, ßp > 2) scenario characterized by a sustained core internal transport barrier (ITB) and a modest edge transport barrier (ETB) in DIII-D tokamak. The high-ßp high-confinement scenario facilitates divertor detachment which, in turn, promotes the development of an even stronger ITB at large radius with a weaker ETB. This self-organized synergy between ITB and ETB, leads to a net gain in energy confinement, in contrast to the net confinement loss caused by divertor detachment in standard H-modes. These results show the potential of integrating excellent core plasma performance with an efficient divertor solution, an essential step towards steady-state operation of reactor-grade plasmas.

6.
Waste Manag ; 102: 528-540, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31765973

RESUMO

The present paper aims to investigate the relationship between achieved recycling rates and the competitiveness of firms working in circular economy sectors. The econometric analysis is based on the Stochastic Frontier Analysis (a parametric model) and is carried out in reference to seventeen European countries over the years 2010-2016. It reveals intriguing results about the positive effect that achieved recycling rates of packaging, electronic and bio-waste can exert on the competitiveness of firms, although differences emerge across the countries considered. Furthermore, through the inefficiency function, a positive effect of R&D spending on competitiveness of European firms is disclosed.


Assuntos
Resíduos Sólidos , Gerenciamento de Resíduos , Europa (Continente) , Embalagem de Produtos , Reciclagem
7.
Phys Rev Lett ; 123(22): 225002, 2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31868395

RESUMO

We report on the first direct comparisons of microtearing turbulence simulations to experimental measurements in a representative high bootstrap current fraction (f_{BS}) plasma. Previous studies of high f_{BS} plasmas carried out in DIII-D with large radius internal transport barriers (ITBs) have found that, while the ion energy transport is accurately reproduced by neoclassical theory, the electron transport remains anomalous and not well described by existing quasilinear transport models. A key feature of these plasmas is the large value of the normalized pressure gradient, which is shown to completely stabilize conventional drift-wave and kinetic ballooning mode instabilities in the ITB, but destabilizes the microtearing mode. Nonlinear gyrokinetic simulations of the ITB region performed with the cgyro code demonstrate that the microtearing modes are robustly unstable and capable of driving electron energy transport levels comparable to experimental levels for input parameters consistent with the experimental measurements. These simulations uniformly predict that the microtearing mode fluctuation and flux spectra extend to significantly shorter wavelengths than the range of linear instability, representing significantly different nonlinear dynamics and saturation mechanisms than conventional drift-wave turbulence, which is also consistent with the fundamental tearing nature of the instability. The predicted transport levels are found to be most sensitive to the magnetic shear, rather than the temperature gradients more typically identified as driving turbulent plasma transport.

8.
Ultrasound Obstet Gynecol ; 47(3): 302-7, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25964123

RESUMO

OBJECTIVES: To evaluate the accuracy of ultrasound in the diagnosis of placenta accreta and its variants, and to assess the impact of prenatal diagnosis in our population. METHODS: A total of 314 women with placenta previa were enrolled prospectively and underwent transabdominal and transvaginal ultrasound examinations. An ultrasound diagnosis (grayscale and color/power Doppler) of placental attachment disorder (PAD) was based on the detection of at least two of the following ('two-criteria system'): loss/irregularity of the retroplacental clear zone, thinning/interruption of the uterine serosa-bladder wall interface, turbulent placental lacunae with high velocity flow, myometrial thickness < 1 mm, increased vascularity of the uterine serosa-bladder wall interface, loss of vascular arch parallel to the basal plate and/or irregular intraplacental vascularization. Definitive diagnosis was made at delivery by Cesarean section. Maternal outcome in cases diagnosed antenatally was compared with that in cases diagnosed at delivery. RESULTS: There were 37/314 cases of PAD (29 anterior and eight posterior). The two-criteria system identified 30 cases of placenta accreta, providing a sensitivity of 81.1% and specificity of 98.9%. When anterior and posterior placentae were considered separately, the detection rates of PAD were 89.7 and 50.0%, respectIvely. Maternal outcome was better in women with prenatal diagnosis of PAD, as seen by less blood loss and shorter hospitalization. CONCLUSIONS: Our data confirmed that grayscale and color Doppler ultrasound have good performance in the diagnosis of PAD and that prenatal diagnosis improves maternal outcome. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Placenta Acreta/diagnóstico por imagem , Diagnóstico Pré-Natal/métodos , Ultrassonografia Pré-Natal/métodos , Adulto , Cesárea , Feminino , Humanos , Avaliação de Resultados em Cuidados de Saúde , Placenta/diagnóstico por imagem , Placenta/patologia , Placenta Acreta/patologia , Gravidez , Estudos Prospectivos , Sensibilidade e Especificidade , Ultrassonografia Doppler em Cores/métodos , Útero/diagnóstico por imagem , Útero/patologia
9.
Br J Cancer ; 113(2): 242-51, 2015 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-26103574

RESUMO

BACKGROUND: Survivin and monoamine oxidase A (MAOA) levels are elevated in prostate cancer (PCa) compared to normal prostate glands. However, the relationship between survivin and MAOA in PCa is unclear. METHODS: We examined MAOA expression in the prostate lobes of a conditional PTEN-deficient mouse model mirroring human PCa, with or without survivin knockout. We also silenced one gene at a time and examined the expression of the other. We further evaluated the combination of MAOA inhibitors and survivin suppressants on the growth, viability, migration and invasion of PCa cells. RESULTS: Survivin and MAOA levels are both increased in clinical PCa tissues and significantly associated with patients' survival. Survivin depletion delayed MAOA increase during PCa progression, and silencing MAOA decreased survivin expression. The combination of MAOA inhibitors and the survivin suppressants (YM155 and SC144) showed significant synergy on the inhibition of PCa cell growth, migration and invasion with concomitant decrease in survivin and MMP-9 levels. CONCLUSIONS: There is a positive feedback loop between survivin and MAOA expression in PCa. Considering that survivin suppressants and MAOA inhibitors are currently available in clinical trials and clinical use, their synergistic effects in PCa support a rapid translation of this combination to clinical practice.


Assuntos
Proteínas Inibidoras de Apoptose/antagonistas & inibidores , Inibidores da Monoaminoxidase/farmacologia , Monoaminoxidase/análise , PTEN Fosfo-Hidrolase/análise , Neoplasias da Próstata/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sinergismo Farmacológico , Humanos , Hidrazinas/farmacologia , Proteínas Inibidoras de Apoptose/análise , Masculino , Camundongos , Neoplasias da Próstata/química , Neoplasias da Próstata/patologia , Quinoxalinas/farmacologia , Survivina
10.
Indian J Surg ; 77(Suppl 1): 13-5, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25972629

RESUMO

Primary venous leiomyosarcoma is very rare and first description was made by Perl in 1871. Most cases are from venous system and half of them are reported to originate in inferior vena cava. We report the case of a 77-year-old Caucasian man with a leiomyosarcoma of the femoral vein. A leg preservation surgery was decided. Eight months later, the patient died of tumor progression. A PubMed search using the terms "leiomyosarcoma femoral vein" and "leiomyosarcoma vein" was performed. All cases of composite iliac-femoral leiomyosarcoma were excluded, and as far as possible, only well-documented cases were included. Median age was 55 years, seven men and six women, tumor resection was performed by six authors, six others performed a vascular resection, and one preferred for a thigh excision. Prognosis remains poor if metastasis is present, and in these cases, a conservative surgery is recommended to preserve patients' quality of life.

11.
J Mater Chem B ; 3(8): 1484-1494, 2015 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32262421

RESUMO

The functionalization of spherical superparamagnetic iron oxide nanoparticles (SPION) of 10 nm with a linear monophosphonate (L1) and also PEGylated mono-phosphonated dendrons of growing generation (D2-G1, -G2 and -G3) yielded dendritic nano-objects of 15 to 30 nm in size, stable in physiological media and showing both renal and hepatobiliary elimination. The grafting of the different molecules has been confirmed by IR spectroscopy and elemental analysis. The colloidal stability of functionalized NS10 has been evaluated in water and in different physiological media. All functionalized NS10 were stable over a long period of time and displayed a mean hydrodynamic diameter smaller than 50 nm whatever the molecule architecture or dendron generation. Only the NS10@L1 showed less stability in biological media at high ionic concentration. NMRD profiles and relaxivity measurements highlighted the influence of the molecule architecture on the water diffusion close to the magnetic core thus influencing the relaxation properties at low magnetic field. Coupling of a fluorescent dye on the functionalized NS10 allowed investigating their biodistribution and highlighting urinary and hepato-biliary eliminations.

12.
Phys Rev Lett ; 113(13): 135001, 2014 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-25302895

RESUMO

A path to a new high performance regime has been discovered in tokamaks that could improve the attractiveness of a fusion reactor. Experiments on DIII-D using a quiescent H-mode edge have navigated a valley of improved edge peeling-ballooning stability that opens up with strong plasma shaping at high density, leading to a doubling of the edge pressure over the standard H mode with edge localized modes at these parameters. The thermal energy confinement time increases as a result of both the increased pedestal height and improvements in the core transport and reduced low-k turbulence. Calculations of the pedestal height and width as a function of density using constraints imposed by peeling-ballooning and kinetic-ballooning theory are in quantitative agreement with the measurements.

13.
Eur J Surg Oncol ; 40(8): 950-6, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24246609

RESUMO

The incidence of infectious complications due to several contributory causes is particularly elevated and life-threatening in patients undergoing peritonectomy and HIPEC procedure for peritoneal carcinomatosis. Following a previous experience, we started a prospective protocol study of preoperative screening, perioperative prophylaxis and postoperative surveillance and treatment. A total of 111 patients with peritoneal carcinomatosis of various origin underwent CRS with HIPEC between April 2004 and December 2012. The group was divided into a pilot group of 30 patients (04/04 to 05/08) and a main group of 81 patients (06/08 to 12/12). Overall postoperative morbidity rate was 44%, with 35.8% of symptomatic infections. No post-operative mortality was observed. Microorganisms were isolated in 24 patients (80.0%) in the first group and 54 (66.7%) in the second. They were symptomatic in 18 cases (75.0%) and 25 (46.3%) cases respectively. In addition, 7 invasive candidosis were recorded (25.9%). Colon resection (P = 0.01) and duration of surgery (P = 0.0008) were associated with infection at logistic regression model. Concerning symptomatic infections, only Infection Risk Index (P = 0.009) showed significance at multivariate analysis. Despite a significant incidence of infectious complications, establishment of a prevention, surveillance and treatment protocol lead to a zero mortality rate in the observed patients of our experience. Owing to the obtained results, we suggest the use of a standardized protocol for the prevention, monitoring and treatment in all patients enrolled for cytoreductive surgery and HIPEC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Infecções Bacterianas/etiologia , Infecções Bacterianas/terapia , Carcinoma/terapia , Quimioterapia do Câncer por Perfusão Regional , Desinfecção/métodos , Hipertermia Induzida , Neoplasias Peritoneais/terapia , Prevenção Primária/métodos , Adolescente , Adulto , Idoso , Antibioticoprofilaxia , Bacteriemia/etiologia , Bacteriemia/terapia , Infecções Bacterianas/microbiologia , Infecções Bacterianas/prevenção & controle , Carcinoma/tratamento farmacológico , Carcinoma/cirurgia , Quimioterapia Adjuvante , Quimioterapia do Câncer por Perfusão Regional/métodos , Protocolos Clínicos , Drenagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Micoses/etiologia , Micoses/terapia , Cavidade Peritoneal , Neoplasias Peritoneais/tratamento farmacológico , Neoplasias Peritoneais/cirurgia , Vigilância da População , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/terapia , Estudos Prospectivos , Infecção da Ferida Cirúrgica/etiologia , Infecção da Ferida Cirúrgica/terapia , Infecções Urinárias/etiologia , Infecções Urinárias/terapia
14.
J Mater Chem B ; 2(13): 1779-1790, 2014 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32261515

RESUMO

A majority of MRI procedures requiring intravascular injections of contrast agents are performed with paramagnetic chelates. Such products induce vascular signal enhancement and they are rapidly excreted by the kidneys. Unfortunately, each chelate is made of only one paramagnetic ion, which, taken individually, has a limited impact on the MRI signal. In fact, the detection of molecular events in the nanomolar range using T1-weighted MRI sequences requires the design of ultra-small particles containing hundreds of paramagnetic ions per contrast agent unit. Ultra-small nanoparticles of manganese oxide (MnO, 6-8 nm diameter) have been developed and proposed as an efficient and at least 1000× more sensitive "positive" MRI contrast agent. However no evidence has been found until now that an adequate surface treatment of these particles could maintain their strong blood signal enhancement, while allowing their rapid and efficient excretion by the kidneys or by the hepatobiliairy pathway. Indeed, the sequestration of MnO particles by the reticuloendothelial system followed by strong uptake in the liver and in the spleen could potentially lead to Mn2+-induced toxicity effects. For ultra-small MnO particles to be applied in the clinics, it is necessary to develop coatings that also enable their efficient excretion within hours. This study demonstrates for the first time the possibility to use MnO particles as T1 vascular contrast agents, while enabling the excretion of >70% of all the Mn injected doses after 48 h. For this, small, biocompatible and highly hydrophilic pegylated bis-phosphonate dendrons (PDns) were grafted on MnO particles to confer colloidal stability, relaxometric performance, and fast excretion capacity. The chemical and colloidal stability of MnO@PDn particles were confirmed by XPS, FTIR and DLS. The relaxometric performance of MnO@PDns as "positive" MRI contrast agents was assessed (r1 = 4.4 mM-1 s-1, r2/r1 = 8.6; 1.41 T and 37 °C). Mice were injected with 1.21 µg Mn per kg (22 µmol Mn per kg), and scanned in MRI up to 48 h. The concentration of Mn in key organs was precisely measured by neutron activation analysis and confirmed, with MRI, the possibility to avoid RES nanoparticle sequestration through the use of phosphonate dendrons. Due to the fast kidney and hepatobiliairy clearance of MnO particles conferred by PDns, MnO nanoparticles can now be considered for promising applications in T1-weighted MRI applications requiring less toxic although highly sensitive "positive" molecular contrast agents.

15.
J Endocrinol Invest ; 36(6): 390-5, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23095310

RESUMO

Androgens' metabolism and activity are gaining a more and more important role in human physiology particularly referring to aging and to neurodegenerative diseases. Androgen treatment is often required for long-lasting disorders. In order to improve their duration and effects, androgens can be administered as esters of carboxylic acids. The novelty of our research is the use of esters of androgens with specific unsaturated fatty acids, in order to reduce possible side effects particularly related to chronic pathologies with altered lipid homeostasis such as X-linked adrenoleukodystrophy and cardiovascular disorders. Thus the esters of the main androgenic substances testosterone, dihydrotestosterone (DHT) and their metabolite 5α-androstan-3α,17ß-diol were chemically obtained by coupling with different unsaturated fatty acids. To this aim, fatty acids with various degree of unsaturation and belonging to different series were selected. Specifically, oleic acid (18:1, n-9), linoleic acid (18:2, n-6), and the n-3 fatty acids, α-linolenic acid (18:3), eicosapentaenoic acid (EPA, 20:5), and docosahexaenoic acid (DHA, 22:6) were used obtaining corresponding esters with acceptable yields and good degree of purity. All the synthesized compounds were tested for their cytotoxic activities in mouse NIH3T3 and human astrocyte cell lines. The esters demonstrated good tolerability and no in vitro cytotoxic effect in both cell cultures. After these promising preliminary results, the esters will be suitable for in vivo studies in order to ascertain their pharmacokinetic characteristics and their biological effects.


Assuntos
Ésteres/síntese química , Ácidos Graxos Insaturados/química , Congêneres da Testosterona/síntese química , Congêneres da Testosterona/uso terapêutico , Adipócitos/efeitos dos fármacos , Adipócitos/fisiologia , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Ésteres/farmacologia , Ésteres/uso terapêutico , Terapia de Reposição Hormonal/métodos , Humanos , Camundongos , Modelos Biológicos , Células NIH 3T3 , Congêneres da Testosterona/farmacologia
16.
Cell Death Dis ; 3: e423, 2012 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-23152059

RESUMO

Micro RNAs (miRs) are small non-coding RNAs aberrantly expressed in human tumors. Here, we aim to identify miRs whose deregulated expression leads to the activation of oncogenic pathways in human gastric cancers (GCs). Thirty nine out of 123 tumoral and matched uninvolved peritumoral gastric specimens from three independent European subsets of patients were analyzed for the expression of 851 human miRs using Agilent Platform. The remaining 84 samples were used to validate miRs differentially expressed between tumoral and matched peritumoral specimens by qPCR. miR-204 falls into a group of eight miRs differentially expressed between tumoral and peritumoral samples. Downregulation of miR-204 has prognostic value and correlates with increased staining of Bcl-2 protein in tumoral specimens. Ectopic expression of miR-204 inhibited colony forming ability, migration and tumor engraftment of GC cells. miR-204 targeted Bcl-2 messenger RNA and increased responsiveness of GC cells to 5-fluorouracil and oxaliplatin treatment. Ectopic expression of Bcl-2 protein counteracted miR-204 pro-apoptotic activity in response to 5-fluorouracil. Altogether, these findings suggest that modulation of aberrant expression of miR-204, which in turn releases oncogenic Bcl-2 protein activity might hold promise for preventive and therapeutic strategies of GC.


Assuntos
MicroRNAs/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Neoplasias Gástricas/genética , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Fluoruracila/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Camundongos Nus , MicroRNAs/metabolismo , Compostos Organoplatínicos/farmacologia , Oxaliplatina , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/metabolismo , Regulação para Cima
17.
Phys Rev Lett ; 106(22): 225002, 2011 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-21702606

RESUMO

Observation of a theoretically predicted peak in the neoclassical toroidal viscosity (NTV) force as a function of toroidal plasma rotation rate Ω is reported. The NTV was generated by applying n=3 magnetic fields from internal coils to low Ω plasmas produced with nearly balanced neutral beam injection. Locally, the peak corresponds to a toroidal rotation rate Ω(0) where the radial electric field E(r) is near zero as determined by radial ion force balance.

18.
Phys Rev Lett ; 106(21): 215002, 2011 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-21699306

RESUMO

Active measurements of the plasma stability in tokamak plasmas reveal the importance of kinetic resonances for resistive wall mode stability. The rotation dependence of the magnetic plasma response to externally applied quasistatic n=1 magnetic fields clearly shows the signatures of an interaction between the resistive wall mode and the precession and bounce motions of trapped thermal ions, as predicted by a perturbative model of plasma stability including kinetic effects. The identification of the stabilization mechanism is an essential step towards quantitative predictions for the prospects of "passive" resistive wall mode stabilization, i.e., without the use of an "active" feedback system, in fusion-alpha heated plasmas.

19.
Eur J Surg Oncol ; 37(2): 148-54, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21093205

RESUMO

AIM: The present study was specifically designed to assess the major clinical and pathological variables of patients with colorectal peritoneal carcinomatosis in order to investigate whether currently used criteria appropriately select candidates for peritonectomy procedures (cytoreductive surgery) combined with hyperthermic intraperitoneal chemotherapy (HIPEC). PATIENTS AND METHODS: Preoperative, operative and follow-up data on 146 consecutive patients presenting with peritoneal carcinomatosis of colorectal origin and treated by surgical cytoreduction combined with HIPEC in 5 Italian Hospital and University Centers were prospectively entered in a common database. Univariate and multivariate analyses were used to assess the prognostic value of clinical and pathologic factors. RESULTS: Over a minimum 24-month follow-up, the overall morbidity rate was 27.4% (mortality rate: 2.7%) and was directly related to the extent of surgery. Peritoneal cancer index (PCI), unfavorable peritoneal sites, synchronous or previously resected liver metastasis and the completeness of cytoreduction, all emerged as independent prognostic factors correlated with survival. CONCLUSIONS: Until research provides more effective criteria for selecting patients based upon the biomolecular features of carcinomatosis, patients should be selected according to the existing independent prognostic variables.


Assuntos
Carcinoma/terapia , Neoplasias Colorretais/terapia , Hipertermia Induzida , Neoplasias Peritoneais/terapia , Adulto , Idoso , Terapia Combinada , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Feminino , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Prognóstico , Resultado do Tratamento
20.
J Surg Oncol ; 100(4): 331-4, 2009 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-19697441

RESUMO

Malignant ascites is a debilitating condition affecting cancer patients in their terminal stage of disease. Recently, laparoscopic hyperthermic intraperitoneal peroperative chemotherapy (HIPEC) was introduced as a new approach. From September 2001 to August 2008, 52 patients were treated with this new modality. No treatment-related mortality was observed. Median survival was 98 days. One patient developed a clinical recurrence. Laparoscopic HIPEC is a safe and effective method for palliating malignant ascites.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ascite/terapia , Quimioterapia do Câncer por Perfusão Regional , Resistencia a Medicamentos Antineoplásicos , Laparoscopia , Neoplasias/tratamento farmacológico , Neoplasias/cirurgia , Adulto , Idoso , Ascite/etiologia , Ascite/patologia , Cisplatino/administração & dosagem , Terapia Combinada , Doxorrubicina/administração & dosagem , Feminino , Humanos , Hipertermia Induzida , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias/patologia , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
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