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Magnetization of inertial confinement implosions is a promising means of improving their performance, owing to the potential reduction of energy losses within the target and mitigation of hydrodynamic instabilities. In particular, cylindrical implosions are useful for studying the influence of a magnetic field, thanks to their axial symmetry. Here, we present experimental results from cylindrical implosions on the OMEGA-60 laser using a 40-beam, 14.5 kJ, 1.5 ns drive and an initial seed magnetic field of B0 = 30 T along the axes of the targets, compared with reference results without an imposed B-field. Implosions were characterized using time-resolved x-ray imaging from two orthogonal lines of sight. We found that the data agree well with magnetohydrodynamic simulations, once radiation transport within the imploding plasma is considered. We show that for a correct interpretation of the data in these types of experiments, explicit radiation transport must be taken into account.
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Plasma density measurements are key to a wide variety of high-energy-density (HED) and laboratory astrophysics experiments. We present a creative application of photonic Doppler velocimetry (PDV) from which time- and spatially resolved electron density measurements can be made. PDV has been implemented for the first time in close proximity, â¼6 cm, to the high-intensity radiation flux produced by a z-pinch dynamic hohlraum on the Z-machine. Multiple PDV probes were incorporated into the photoionized gas cell platform. Two probes, spaced 4 mm apart, were used to assess plasma density and uniformity in the central region of the gas cell during the formation of the plasma. Electron density time histories with subnanosecond resolution were extracted from PDV measurements taken from the gas cells fielded with neon at 15 Torr. As well, a null shot with no gas fill in the cell was fielded. A major achievement was the low noise high-quality measurements made in the harsh environment produced by the mega-joules of x-ray energy emitted at the collapse of the z-pinch implosion. To evaluate time dependent radiation induced effects in the fiber optic system, two PDV noise probes were included on either side of the gas cell. The success of this alternative use of PDV demonstrates that it is a reliable, precise, and affordable new electron density diagnostic for radiation driven experiments and more generally HED experiments.
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PURPOSE: This series was aimed to analyze feasibility, safety and postoperative quality of life of trans-abdominal pre-peritoneal repair in incarcerated hernia; the rationale was a safe hernia reduction, more accurate abdomen exploration, diagnosis and treatment of contralateral unknown hernia. METHODS: With a minimum follow-up of 30 months, 20 urgent incarcerated inguinal hernia patients were submitted to TAPP. Signs of strangulation, peritonitis and major comorbidity were exclusion criteria. Feasibility and safety were evaluated by ability to hernia reduction, conversion rate, operative time, perioperative mortality, morbidity, hospital stay, prosthesis infection and recurrence. Finally, quality of life was assessed by acute and chronic pain score, recovery of normal activities, return to work and patients' satisfaction survey. RESULTS: Under vision sac reduction was always achieved, incision of internal ring during the reduction manoeuvre was necessary in 40% of pts, intraoperative complications, conversions or perioperative mortality were not observed. In one case (5%) partial omentectomy was necessary. Contralateral hernia was diagnosed and repaired in 20%. Median operative time was 81.3 min, postoperative minor complications were recorded in 5 patients (25%), median in hospital stay was 2 days. After a median follow-up of 39 months, 1 patient recurred (5%). Acute pain, was scored 3 as median value (range 1-5), only one patient scored 2 as chronic pain during follow-up. CONCLUSIONS: Laparoscopic approach for incarcerated inguinal hernia repair is not the standard treatment. In our experience, with the limit of a single-surgeon series, selected patients showed satisfactory results in terms of feasibility, safety, postoperative quality of life and patients' satisfaction were observed. Few series about this topic were published. More prospective trials are needed.
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Hérnia Inguinal/complicações , Hérnia Inguinal/cirurgia , Herniorrafia/métodos , Peritônio/cirurgia , Parede Abdominal/cirurgia , Adulto , Idoso , Estudos de Viabilidade , Feminino , Hérnia Inguinal/diagnóstico , Humanos , Laparoscopia , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Estudos Prospectivos , Qualidade de Vida , Resultado do TratamentoRESUMO
OBJECTIVE: To evaluate the expression of microRNA (miR)-551b in patients with low and high grade cervical intraepithelial neoplasia (CIN) and to find an association with high-risk Human Papillomavirus (HR-HPV) infection-related prognostic biomarkers. PATIENTS AND METHODS: The expression level of miR-551b was determined in 50 paraffin-embedded cervical specimens (10 normal squamous epithelium, 18 condylomas, 8 CIN1, and 14 CIN2-3) using quantitative Real-time polymerase chain reaction (qRT-PCR). χ2-test compared miR-551b expression in different diagnosis groups. An Ordered Logistic Regression and a Probit correlation were made to correlate miR-551b expression levels with the cervical tissue histological findings. The immunohistochemical distribution of p16 and Ki-67 according to histopathological findings was also assessed. RESULTS: The distribution of the miR-551b expression profile was significantly lower in CIN1-3 samples compared to other histological diagnosis groups (condyloma and negative). The expression levels were inversely correlated to the cervical pathological grade, from negative to CIN2-3. A 1% increase in miR-551b expression level produced an increase of 19% to the probability of a minor histological grade diagnosis in a range from negative to CIN2-3 and an increase of 13% to the probability of a negative histological grade diagnosis. Among the cases with miR-551b expression < 0.02 (considered as cut-off value) a significant statistical correlation was found between p16 and Ki-67 expression and the diagnosis of CIN2-3. CONCLUSIONS: Our data showed a significant inverse correlation between miR-551b expression and the histological grading of the lesions, suggesting a tumor suppressive function in the different stages of cervical dysplasia.
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Carcinogênese/genética , Genes Supressores de Tumor , MicroRNAs/metabolismo , Displasia do Colo do Útero/genética , Neoplasias do Colo do Útero/genética , Adulto , Ciclo Celular/genética , Colo do Útero/patologia , Feminino , Perfilação da Expressão Gênica , Humanos , Pessoa de Meia-Idade , Gradação de Tumores , Neoplasias do Colo do Útero/patologia , Displasia do Colo do Útero/patologiaRESUMO
This corrects the article DOI: 10.1038/onc.2017.75.
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Recent evidences suggest that stearoyl-CoA-desaturase 1 (SCD1), the enzyme involved in monounsaturated fatty acids synthesis, has a role in several cancers. We previously demonstrated that SCD1 is important in lung cancer stem cells survival and propagation. In this article, we first show, using primary cell cultures from human lung adenocarcinoma, that the effectors of the Hippo pathway, Yes-associated protein (YAP) and transcriptional co-activator with PDZ-binding motif (TAZ), are required for the generation of lung cancer three-dimensional cultures and that SCD1 knock down and pharmacological inhibition both decrease expression, nuclear localization and transcriptional activity of YAP and TAZ. Regulation of YAP/TAZ by SCD1 is at least in part dependent upon ß-catenin pathway activity, as YAP/TAZ downregulation induced by SCD1 blockade can be rescued by the addition of exogenous wnt3a ligand. In addition, SCD1 activation of nuclear YAP/TAZ requires inactivation of the ß-catenin destruction complex. In line with the in vitro findings, immunohistochemistry analysis of lung adenocarcinoma samples showed that expression levels of SCD1 co-vary with those of ß-catenin and YAP/TAZ. Mining available gene expression data sets allowed to observe that high co-expression levels of SCD1, ß-catenin, YAP/TAZ and downstream targets have a strong negative prognostic value in lung adenocarcinoma. Finally, bioinformatics analyses directed to identify which gene combinations had synergistic effects on clinical outcome in lung cancer showed that poor survival is associated with high co-expression of SCD1, ß-catenin and the YAP/TAZ downstream target birc5. In summary, our data demonstrate for the first time the involvement of SCD1 in the regulation of the Hippo pathway in lung cancer, and point to fatty acids metabolism as a key regulator of lung cancer stem cells.
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Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adenocarcinoma/metabolismo , Núcleo Celular/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias Pulmonares/metabolismo , Células-Tronco Neoplásicas/metabolismo , Fosfoproteínas/metabolismo , Estearoil-CoA Dessaturase/metabolismo , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adenocarcinoma de Pulmão , Complexo de Sinalização da Axina/metabolismo , Regulação para Baixo , Ácidos Graxos/metabolismo , Feminino , Células HEK293 , Via de Sinalização Hippo , Humanos , Imuno-Histoquímica , Proteínas Inibidoras de Apoptose/metabolismo , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Masculino , Proteínas de Neoplasias/metabolismo , Cultura Primária de Células , Prognóstico , Proteínas Serina-Treonina Quinases/metabolismo , Estabilidade Proteica , RNA Mensageiro/metabolismo , Estearoil-CoA Dessaturase/antagonistas & inibidores , Estearoil-CoA Dessaturase/genética , Survivina , Transativadores , Fatores de Transcrição , Proteínas com Motivo de Ligação a PDZ com Coativador Transcricional , Proteína Wnt3A/metabolismo , Proteínas de Sinalização YAPRESUMO
Nearly a century ago it was recognized that radiation absorption by stellar matter controls the internal temperature profiles within stars. Laboratory opacity measurements, however, have never been performed at stellar interior conditions, introducing uncertainties in stellar models. A particular problem arose when refined photosphere spectral analysis led to reductions of 30-50 per cent in the inferred amounts of carbon, nitrogen and oxygen in the Sun. Standard solar models using the revised element abundances disagree with helioseismic observations that determine the internal solar structure using acoustic oscillations. This could be resolved if the true mean opacity for the solar interior matter were roughly 15 per cent higher than predicted, because increased opacity compensates for the decreased element abundances. Iron accounts for a quarter of the total opacity at the solar radiation/convection zone boundary. Here we report measurements of wavelength-resolved iron opacity at electron temperatures of 1.9-2.3 million kelvin and electron densities of (0.7-4.0) × 10(22) per cubic centimetre, conditions very similar to those in the solar region that affects the discrepancy the most: the radiation/convection zone boundary. The measured wavelength-dependent opacity is 30-400 per cent higher than predicted. This represents roughly half the change in the mean opacity needed to resolve the solar discrepancy, even though iron is only one of many elements that contribute to opacity.
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In recent years, studies of cancer development and recurrence have been influenced by the cancer stem cells (CSCs)/cancer-initiating cells (CICs) hypothesis. According to this, cancer is sustained by highly positioned, chemoresistant cells with extensive capacity of self renewal, which are responsible for disease relapse after chemotherapy. Growth of cancer cells as three-dimensional non-adherent spheroids is regarded as a useful methodology to enrich for cells endowed with CSC-like features. We have recently reported that cell cultures derived from malignant pleural effusions (MPEs) of patients affected by adenocarcinoma of the lung are able to efficiently form spheroids in non-adherent conditions supplemented with growth factors. By expression profiling, we were able to identify a set of genes whose expression is significantly upregulated in lung tumor spheroids versus adherent cultures. One of the most strongly upregulated gene was stearoyl-CoA desaturase (SCD1), the main enzyme responsible for the conversion of saturated into monounsaturated fatty acids. In the present study, we show both by RNA interference and through the use of a small molecule inhibitor that SCD1 is required for lung cancer spheroids propagation both in stable cell lines and in MPE-derived primary tumor cultures. Morphological examination and image analysis of the tumor spheroids formed in the presence of SCD1 inhibitors showed a different pattern of growth characterized by irregular cell aggregates. Electron microscopy revealed that the treated spheroids displayed several features of cellular damage and immunofluorescence analysis on optical serial sections showed apoptotic cells positive for the M30 marker, most of them positive also for the stemness marker ALDH1A1, thus suggesting that the SCD1 inhibitor is selectively killing cells with stem-like properties. Furthermore, SCD1-inhibited lung cancer cells were strongly impaired in their in vivo tumorigenicity and ALDH1A1 expression. These results suggest that SCD1 is a critical target in lung cancer tumor-initiating cells.
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Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Células-Tronco Neoplásicas/enzimologia , Células-Tronco Neoplásicas/patologia , Estearoil-CoA Dessaturase/metabolismo , Aldeído Desidrogenase/genética , Aldeído Desidrogenase/metabolismo , Família Aldeído Desidrogenase 1 , Anoikis/fisiologia , Humanos , Derrame Pleural Maligno/metabolismo , Derrame Pleural Maligno/patologia , Retinal Desidrogenase , Estearoil-CoA Dessaturase/genéticaRESUMO
The aim of this study was to assess the effects of three weeks of daily colostrum cream on vaginal cytology and local symptoms related to menopause. Genito-urinary symptoms and cell morphology were analyzed at time 0 (T0) and after three weeks (16 +/- days since the end of treatment) at time 1 (T1). Dyspareunia, vaginal dryness, and maturation index (MI) reached a statistically significant difference between T0 and T1. The results proved to be an alternative treatment for vaginal distress caused by lack of hormones in patients in which hormonal treatment is contraindicated.
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Colostro , Menopausa , Doenças Vaginais/terapia , Dispareunia/terapia , Feminino , Humanos , Vagina/patologia , Cremes, Espumas e Géis Vaginais , Doenças Vaginais/patologia , Esfregaço VaginalRESUMO
Experiments have been performed at Sandia National Laboratories Z-facility to validate iron opacity models relevant to the solar convection/radiation zone boundary. Sample conditions were measured by mixing Mg with the Fe and using Mg K-shell line transmission spectra, assuming that the plasma was uniform. We develop a spectral model that accounts for hypothetical gradients, and compute synthetic spectra to quantitatively evaluate the plasma gradient size that can be diagnosed. Two sample designs are investigated, assuming linear temperature and density gradients. First, Mg uniformly mixed with Fe enables temperature gradients greater than 10% to be detected. The second design uses Mg mixed into one side and Al mixed into the other side of the sample in an attempt to more accurately infer the sample gradient. Both temperature and density gradients as small as a few percent can be detected with this design. Experiments have successfully recorded spectra with the second design. In future research, the spectral model will be used to place bounds on gradients that exist in Z opacity experiments.
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BACKGROUND: Although fine-needle aspiration cytology remains the mainstay of the preoperative workup of thyroid nodules, those with follicular proliferation still represent a diagnostic challenge. Real-time elastography (RTE) estimates the stiffness/elasticity of lesions and is regarded as a promising technique for the presurgical selection of thyroid nodules (including those with indeterminate cytology). AIM: Our aim was to verify the potential role of RTE in the presurgical diagnosis of cancer in a large cohort of consecutive patients with follicular thyroid nodules. PATIENTS AND METHODS: One hundred two patients were submitted to conventional ultrasonography and RTE evaluation before being operated on for thyroid nodule with indeterminate cytology (54% single nodules). Tissue stiffness on RTE was scored from 1 (greatest elasticity) to 4 (no elasticity). RESULTS: At conventional ultrasonography examination, the nodules (median diameter 2.2 cm) were solid (cystic areas < 10%); microcalcifications were detected in 56% of them and a hypoechoic pattern in 64%. Elasticity was high in eight cases only (score 1-2) although low in 94 (score 3-4). Cancer was diagnosed in 36 nodules (35%), being associated with microcalcifications (P < 0.0001) and inversely related to nodule diameter (P < 0.01). Malignancy was detected in 50% of the nodules with RTE score 1-2 and in 34% of those with score 3-4. Therefore, either the positive (34%) or the negative predictive value (50%) was clinically negligible. CONCLUSIONS: The current study does not confirm the recently reported usefulness of RTE in presurgical selection of nodules with indeterminate cytology and suggest the need for quantitative analytical assessment of nodule stiffness to improve RTE efficacy.
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Técnicas de Imagem por Elasticidade , Nódulo da Glândula Tireoide/patologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Nódulo da Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/cirurgiaRESUMO
BACKGROUND: This multi-centre phase II clinical trial is the first prospective evaluation of radioembolisation of patients with colorectal liver metastases (mCRC) who failed previous oxaliplatin- and irinotecan-based systemic chemotherapy regimens. METHODS: Eligible patients had adequate hepatic, haemopoietic and renal function, and an absence of major hepatic vascular anomalies and hepato-pulmonary shunting. Gastroduodenal and right gastric arteries were embolised before hepatic arterial administration of yttrium-90 resin microspheres (median activity, 1.7 GBq; range, 0.9-2.2). RESULTS: Of 50 eligible patients, 38 (76%) had received > or =4 lines of chemotherapy. Most presented with synchronous disease (72%), >4 hepatic metastases (58%), 25-50% replacement of total liver volume (60%) and bilateral spread (70%). Early and intermediate (>48 h) WHO G1-2 adverse events (mostly fever and pain) were observed in 16 and 22% of patients respectively. Two died due to renal failure at 40 days or liver failure at 60 days respectively. By intention-to-treat analysis using Response Evaluation Criteria in Solid Tumours, 1 patient (2%) had a complete response, 11 (22%) partial response, 12 (24%) stable disease, 22 (44%) progressive disease; 4 (8%) were non-evaluable. Median overall survival was 12.6 months (95% CI, 7.0-18.3); 2-year survival was 19.6%. CONCLUSION: Radioembolisation produced meaningful response and disease stabilisation in patients with advanced, unresectable and chemorefractory mCRC.
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Neoplasias Colorretais/patologia , Neoplasias Hepáticas/radioterapia , Neoplasias Hepáticas/secundário , Radioisótopos de Ítrio/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada , Embolização Terapêutica/métodos , Feminino , Artéria Hepática , Humanos , Contagem de Leucócitos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Qualidade de Vida , Análise de Sobrevida , Tomografia Computadorizada por Raios X , Radioisótopos de Ítrio/administração & dosagem , Radioisótopos de Ítrio/efeitos adversosRESUMO
FHIT, at a constitutively active chromosome fragile site, is often a target of chromosomal aberrations and deletion in a large fraction of human tumors. Inactivation of murine Fhit allelessignificantly increases susceptibility of mice to spontaneous and carcinogen-induced tumorigenesis. In this study, transgenic mice, carrying a human FHIT cDNA under control of the endogenous promoter, were produced to determine the effect of Fhit expression, from a nonfragile cDNA transgene outside the fragile region, on carcinogen-induced tumor susceptibility of wildtype and Fhit heterozygous mice. Mice received sufficient oral doses of N-nitrosomethybenzylamine (NMBA) to cause forestomach tumors in >80% of nontransgenic control mice. Although the level of expression of the FHIT transgene in the recombinant mouse strains was much lower than the level of endogenous Fhit expression, the tumor burden in NMBA-treated male transgenic mice was significantly reduced, while female transgenic mice were not protected. To determine if the difference in protection could be due to differences in epigenetic changes at the transgene loci in male versus female mice, we examined expression, hypermethylation and induced re-expression of FHIT transgenes in male and female mice or cells derived from them. The transgene was methylated in male and female mice and in cell lines established from male and female transgenic kidneys, the FHIT locus was both hypermethylated and deacetylated. It is likely that the FHIT transgene is more tightly silenced in female transgenic mice, leading to a lack of protection from tumor induction.
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Hidrolases Anidrido Ácido/genética , Predisposição Genética para Doença , Proteínas de Neoplasias/genética , Neoplasias Experimentais/genética , Transgenes , Animais , Sequência de Bases , Western Blotting , Carcinógenos/toxicidade , Metilação de DNA , Metilases de Modificação do DNA/antagonistas & inibidores , Primers do DNA , Feminino , Inibidores de Histona Desacetilases , Hibridização in Situ Fluorescente , Masculino , Camundongos , Camundongos Transgênicos , Neoplasias Experimentais/induzido quimicamente , Regiões Promotoras Genéticas , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
Measurements of iron-plasma transmission at 156+/-6 eV electron temperature and 6.9+/-1.7 x 10(21) cm(-3) electron density are reported over the 800-1800 eV photon energy range. The temperature is more than twice that in prior experiments, permitting the first direct experimental tests of absorption features critical for understanding solar interior radiation transport. Detailed line-by-line opacity models are in excellent agreement with the data.
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Cystic pancreatic neoplasms have been increasingly diagnosed in the last years. Resection is recommended in most cases, but their management has not been standardized since an accurate nonoperative differentiation is often difficult. A retrospective review of 30 patients undergoing surgical resection for cystic pancreatic neoplasms between 1993 and 2005 was performed. Median age of the patients was 63 years and 63.5% were female. Twelve patients (40%) were asymptomatic. Twenty-nine had curative resections. Pathologic analysis revealed 13 serous cystadenomas, 9 mucinous cystadenomas, 3 mucinous cystadenocarcinomas, 4 intraductal papillary mucinous neoplasms and 1 solid pseudopapillary neoplasm. Overall mortality was 6.5% (2 patients). Postoperative complications occurred in 12 patients (41%). Pancreatic fistula occurred in 7 cases (24%). Reoperation was required in 2 patients (6.5%). Two patients operated for mucinous cystadenocarcinoma and invasive intraductal papillary mucinous neoplasms died of recurrence at 24 and 7 months postoperatively. Excluding another patient died from other cause, all others are currently alive with no evidence of disease. Diagnostic accuracy for cystic pancreatic neoplasms is still limited. Considering the good prognosis and acceptable morbidity and minimal mortality after surgical treatment in specialized centers, resection seems still justified in most cases.
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Cistadenocarcinoma Mucinoso/cirurgia , Cistadenoma Mucinoso/cirurgia , Cistadenoma Seroso/cirurgia , Cisto Pancreático/cirurgia , Neoplasias Pancreáticas/cirurgia , Adulto , Idoso , Carcinoma Papilar/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pâncreas/patologia , Neoplasias Pancreáticas/diagnóstico , Estudos Prospectivos , Estudos RetrospectivosRESUMO
BACKGROUND: In patients locally progressing after two lines of chemotherapy, some locoregional approaches showed encouraging results in terms of local control of disease. The aim of our study was to evaluate toxicity, clinical response and quality of life in 48 patients with unresectable colorectal liver metastases submitted to selective internal radiotherapy (SIRT). MATERIALS AND METHODS: Up to now 35 patients with unresectable colorectal liver metastases, refractory to two lines of chemotherapy, underwent intra-arterial infusion of resin microspheres with yttrium-90 (SIR-spheres). Pre-treatment evaluation included a CT scan, blood tests, a PET scan and arteriography of celiac trunk, hepatic and superior mesenteric artery; extrahepatic uptakes and pulmonary shunts more than 10% were excluded by a Scinti-scan. The gastroduodenal artery was embolized before the SIR-spheres injection. Other exclusion criteria were liver dysfunction and anatomical vascular anomalies. The clinical response was evaluated by CT-scan following the RECIST criteria. Median follow-up was 4 months. RESULTS: Median number of metastases was 4 (range, 1-15), 38% of cases presenting hepatic involvement < 25%. The median SIRT dose delivered was 1.7 GBq. Median pulmonary shunt was 6%. No operative mortality occurred; early toxicity (within 48 hours) was 20.6%, shown as fever, acute pain and leucocytosis. The late toxicity was 24.1% with chronic pain, jaundice and nausea being the most frequent. All the toxic events were graded 2 or 3 according to the WHO scale. Preliminary results were available in terms of clinical response after 6 weeks: 12.5% had a partial response, 75% a stable disease, while progression of disease, was observed in 12.5% of the patients. CONCLUSION: SIRT is a safe treatment in terms of acute and late toxicity. Intra-arterial microspheres could represent a good therapeutic option for patients with progressing liver metastases only, after two lines of systemic chemotherapy.
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Neoplasias Colorretais/radioterapia , Neoplasias Hepáticas/radioterapia , Neoplasias Hepáticas/secundário , Radioisótopos de Ítrio/administração & dosagem , Antineoplásicos/uso terapêutico , Neoplasias Colorretais/patologia , Progressão da Doença , Humanos , Infusões Intra-Arteriais , Microesferas , Estudos Prospectivos , Qualidade de Vida , Dosagem Radioterapêutica , Fatores de Tempo , Resultado do Tratamento , Radioisótopos de Ítrio/efeitos adversosRESUMO
We have investigated molecular changes in cultured differentiating human lens epithelial cells exposed to high-energy accelerated iron-ion beams as well as to protons and X rays. In this paper, we present results on the effects of radiation on gene families that include or are related to DNA damage, cell cycle regulators, cell adhesion molecules, and cell cytoskeletal function. A limited microarray survey with a panel of cell cycle-regulated genes illustrates that irradiation with protons altered the gene expression pattern of human lens epithelial cells. A focus of our work is CDKN1A (p21(CIP1/WAF1)), a protein that we demonstrate here has a role in several pathways functionally related to LET-responsive radiation damage. We quantitatively assessed RNA and protein expression in a time course before and after single 4-Gy radiation doses and demonstrated that transcription and translation of CDKN1A are both temporally regulated after exposure. Furthermore, we show qualitative differences in the distribution of CDKN1A immunofluorescence signals after exposure to X rays, protons or iron ions, suggesting that LET effects likely play a role in the misregulation of gene function in these cells. A model of molecular and cellular events is proposed to account for precataractous changes in the human lens after exposure to low- or high-LET radiations.
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Diferenciação Celular/efeitos da radiação , Íons Pesados/efeitos adversos , Cristalino/efeitos da radiação , Prótons/efeitos adversos , Raios X/efeitos adversos , Ciclo Celular , Proteínas de Ciclo Celular/análise , Proteínas de Ciclo Celular/genética , Inibidor de Quinase Dependente de Ciclina p21 , Células Epiteliais/efeitos da radiação , Humanos , Ferro , Cristalino/citologia , Transferência Linear de EnergiaRESUMO
This study was carried out to determine an effective combination of chelators, reductants and free radical scavengers for enhancing color stability and minimizing lipid oxidation in muscle foods fortified with n-3 fatty acids. Chelators (sodium tripolyphosphate, STPP; sodium citrate, CIT), reductants (sodium erythorbate, ERY) and radical scavengers (butylhydroxyanisole, BHA; mixed tocopherols from two different sources, 30 or 95TOC; rosemary extract, ROSE) were incorporated in various combinations into ground beef (15% fat) with or without n-3 oil fortification (n=8). Individually, STPP and CIT had no significant effect on a* values except day 4, but showed higher a* values when combined with ERY (STPP+ERY and CIT+ERY) (P<0.05). CIT had lower hue angle values than STPP on days 4 and 6, but CIT+ERY showed more discoloration than STPP+ERY (P<0.05). CIT+ERY showed less lipid oxidation than CIT alone (P<0.05), whereas there was no difference between STPP and STPP+ERY. CIT+ERY+ROSE demonstrated higher a* values than CIT+ERY+95TOC on days 4 and 6 (P<0.05); there was no difference between ROSE and 95TOC groups when n-3 oil was incorporated into ground beef patties (P>0.05). The combination of ROSE and ERY appeared to be effective in slowing the decline of a* values. All antioxidant combinations were effective at delaying lipid oxidation when compared to CON or n-3. A combination of CIT, ERY and ROSE was most effective for stabilizing color and delaying lipid oxidation.