47 resultados para ASTRO-R1
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Purpose: To assess the outcome in patients with olfactory neuroblastoma (ONB). Methods and Materials: Seventy-seven patients treated for nonmetastatic ONB between 1971 and 2004 were included. According to Kadish classification, there were 11 patients with Stage A, 29 with Stage B, and 37 with Stage C. T-classification included 9 patients with T1, 26 with T2, 16 with T3, 15 with T4a, and 11 with T4b tumors. Sixty-eight patients presented with N0 (88%) disease. Results: Most of the patients (n = 56, 73 %) benefited from surgery (S), and total excision was possible in 44 patients (R0 in 32, R1 in 13, R2 in 11). All but five patients benefited from RT, and chemotherapy was given in 21(27%). Median follow-up period was 72 months (range, 6-315). The 5-year overall survival (OS), disease-free survival (DES), locoregional control, and local control were 64%, 57%, 62%, and 70%, respectively. In univariate analyses, favorable factors were Kadish A or B disease, T1 T3 tumors, no nodal involvement, curative surgery, R0/R1 resection, and RT-dose 54 Gy or higher. Multivariate analysis revealed that the best independent factors predicting the outcome were T1 T3, N0, R0/R1 resection, and total RT dose (54 Gy or higher). Conclusion: In this multicenter retrospective study, patients with ONB treated with R0 or R1 surgical resection followed by at least 54-Gy postoperative RT had the best outcome. Novel strategies including concomitant chemotherapy and/or higher dose RT should be prospectively investigated in this rare disease for which local failure remains a problem.
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Purpose/Objective(s): Radiotherapy is an effective treatment modality against cancer. Despite recent technical progresses in radiation delivery precision, toxicity to healthy tissues remains the main limiting factor. RasGAP is a regulator of the Ras and Rho pathway; it has either a pro- or anti-apoptotic activity depending on the level of caspase expressed in the cell. The RasGAP derived peptide: TAT-RasGAP317 - 326 is the minimal sequence known to sensitize cancer cells, but not healthy cells, to genotoxin-induced apoptosis. In this study the TAT-RasGAP317 - 326 radio-sensitizing effect was tested in vitro and in vivo.Materials/Methods: Two weeks clonogenic forming assays with 5 human cancer cells (PANC-1, HCT116, U87, U251 and HeLa) and a non tumorigenic cell line (HaCaT) were performed. Cells were exposed to 0, 1, 2 and 4 Gy with or without 20 mMTAT-RasGAP317 - 326. Twenty mMTAT peptide was also used as control. TAT-RasGAP317 - 326 effect was also tested in tumor xenograft mouse models. Mice bearing HCT116 tumors (WT or p53 mutant) received 1.65 mg/kg TAT-RasGAP317 - 326 i.p. injected and were locally irradiated for 10 days with 3 Gy. Tumor volume was then followed during a minimum of 20 days. Control mice were treated with a single modality, either with TAT-RasGAP317 - 326 or with radiotherapy.Results: At all the tested radiation doses TAT-RasGAP317 - 326 showed a significant supra additive radio-sensitizing effect on all the tested tumor cell lines. Furthermore, it showed no sensitizing effect on the non tumorigenic cell line. In vivo, TAT-RasGAP317 - 326 also showed a significantly radio-sensitizing effect as shown by a significant higher reduction in tumor volume as much as by a significant tumor growth delay.Conclusions: Taken together our data suggest that TAT-RasGAP317 - 326 has a radio-sensitizing effect on in vivo and in vitro tumors without any effect on healthy tissues. Therefore TAT-RasGAP317 - 326 should be considered as a novel and attractive sensitizer compound allowing an improvement of the therapeutic interval.
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Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is a member of the TNF family that induces cancer cell death by apoptosis with some selectivity. TRAIL-induced apoptosis is mediated by the transmembrane receptors death receptor 4 (DR4) (also known as TRAIL-R1) and DR5 (TRAIL-R2). TRAIL can also bind decoy receptor 1 (DcR1) (TRAIL-R3) and DcR2 (TRAIL-R4) that fail to induce apoptosis since they lack and have a truncated cytoplasmic death domain, respectively. In addition, DcR1 and DcR2 inhibit DR4- and DR5-mediated, TRAIL-induced apoptosis and we demonstrate here that this occurs through distinct mechanisms. While DcR1 prevents the assembly of the death-inducing signaling complex (DISC) by titrating TRAIL within lipid rafts, DcR2 is corecruited with DR5 within the DISC, where it inhibits initiator caspase activation. In addition, DcR2 prevents DR4 recruitment within the DR5 DISC. The specificity of DcR1- and DcR2-mediated TRAIL inhibition reveals an additional level of complexity for the regulation of TRAIL signaling.
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The Monte Perdido thrust fault (southern Pyrenees) consists of a 6-m-thick interval of intensely deformed clay-bearing rocks. The fault zone is affected by a pervasive pressure solution seam and numerous shear surfaces. Calcite extensional-shear veins are present along the shear surfaces. The angular relationships between the two structures indicate that shear surfaces developed at a high angle (70°) to the local principal maximum stress axis r1. Two main stages of deformation are present. The first stage corresponds to the development of calcite shear veins by a combination of shear surface reactivation and extensional mode I rupture. The second stage of deformation corresponds to chlorite precipitation along the previously reactivated shear surfaces. The pore fluid factor k computed for the two deformation episodes indicates high fluid pressures during the Monte Perdido thrust activity. During the first stage of deformation, the reactivation of the shear surface was facilitated by a suprahydrostatic fluid pressure with a pore fluid factor kv equal to 0.89. For the second stage, the fluid pressure remained still high (with a k value ranging between 0.77 and 0.84) even with the presence of weak chlorite along the shear surfaces. Furthermore, evidence of hydrostatic fluid pressure during calcite cement precipitation supports that incremental shear surface reactivations are correlated with cyclic fluid pressure fluctuations consis- tent with a fault-valve model.
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Six gases (N((CH3)3), NH2OH, CF3COOH, HCl, NO2, O3) were selected to probe the surface of seven combustion aerosol (amorphous carbon, flame soot) and three types of TiO2 nanoparticles using heterogeneous, that is gas-surface reactions. The gas uptake to saturation of the probes was measured under molecular flow conditions in a Knudsen flow reactor and expressed as a density of surface functional groups on a particular aerosol, namely acidic (carboxylic) and basic (conjugated oxides such as pyrones, N-heterocycles) sites, carbonyl (R1-C(O)-R2) and oxidizable (olefinic, -OH) groups. The limit of detection was generally well below 1% of a formal monolayer of adsorbed probe gas. With few exceptions most investigated aerosol samples interacted with all probe gases which points to the coexistence of different functional groups on the same aerosol surface such as acidic and basic groups. Generally, the carbonaceous particles displayed significant differences in surface group density: Printex 60 amorphous carbon had the lowest density of surface functional groups throughout, whereas Diesel soot recovered from a Diesel particulate filter had the largest. The presence of basic oxides on carbonaceous aerosol particles was inferred from the ratio of uptakes of CF3COOH and HCl owing to the larger stability of the acetate compared to the chloride counterion in the resulting pyrylium salt. Both soots generated from a rich and a lean hexane diffusion flame had a large density of oxidizable groups similar to amorphous carbon FS 101. TiO2 15 had the lowest density of functional groups among the three studied TiO2 nanoparticles for all probe gases despite the smallest size of its primary particles. The used technique enabled the measurement of the uptake probability of the probe gases on the various supported aerosol samples. The initial uptake probability, g0, of the probe gas onto the supported nanoparticles differed significantly among the various investigated aerosol samples but was roughly correlated with the density of surface groups, as expected. [Authors]
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The complete mitochondrial DNA (mtDNA) control region was amplified and directly sequenced in two species of shrew, Crocidura russula and Sorex araneus (Insectivora, Mammalia). The general organization is similar to that found in other mammals: a central conserved region surrounded by two more variable domains. However, we have found in shrews the simultaneous presence of arrays of tandem repeats in potential locations where repeats tend to occur separately in other mammalian species. These locations correspond to regions which are associated with a possible interruption of the replication processes, either at the end of the three-stranded D-loop structure or toward the end of the heavy-strand replication. In the left domain the repeated sequences (R1 repeats) are 78 bp long, whereas in the right domain the repeats are 12 bp long in C. russula and 14 bp long in S. araneus (R2 repeats). Variation in the copy number of these repeated sequences results in mtDNA control region length differences. Southern blot analysis indicates that level of heteroplasmy (more than one mtDNA form within an individual) differs between species. A comparative study of the R2 repeats in 12 additional species representing three shrew subfamilies provides useful indications for the understanding of the origin and the evolution of these homologous tandemly repeated sequences. An asymmetry in the distribution of variants within the arrays, as well as the constant occurrence of shorter repeated sequences flanking only one side of the R2 arrays, could be related to asymmetry in the replication of each strand of the mtDNA molecule. The pattern of sequence and length variation within and between species, together with the capability of the arrays to form stable secondary structures, suggests that the dominant mechanism involved in the evolution of these arrays in unidirectional replication slippage.
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PURPOSE: A sacral chordoma is a rare, slow-growing, primary bone tumor, arising from embryonic notochordal remnants. Radical surgery is the only hope for cure. The aim of our present study is to analyse our experience with the challenging treatment of this rare tumor, to review current treatment modalities and to assess the outcome based on R status. METHODS: Eight patients were treated in our institution between 2001 and 2011. All patients were discussed by a multidisciplinary tumor board, and an en bloc surgical resection by posterior perineal access only or by combined anterior/posterior accesses was planned based on tumor extension. RESULTS: Seven patients underwent radical surgery, and one was treated by using local cryotherapy alone due to low performance status. Three misdiagnosed patients had primary surgery at another hospital with R1 margins. Reresection margins in our institution were R1 in two and R0 in one, and all three recurred. Four patients were primarily operated on at our institution and had en bloc surgery with R0 resection margins. One had local recurrence after 18 months. The overall morbidity rate was 86% (6/7 patients) and was mostly related to the perineal wound. Overall, 3 out of 7 resected patients were disease-free at a median follow-up of 2.9 years (range, 1.6-8.0 years). CONCLUSION: Our experience confirms the importance of early correct diagnosis and of an R0 resection for a sacral chordoma invading pelvic structures. It is a rare disease that requires a challenging multidisciplinary treatment, which should ideally be performed in a tertiary referral center.
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Synthetic inhibitor of apoptosis (IAP) antagonists induce degradation of IAP proteins such as cellular IAP1 (cIAP1), activate nuclear factor kappaB (NF-kappaB) signaling, and sensitize cells to tumor necrosis factor alpha (TNFalpha). The physiological relevance of these discoveries to cIAP1 function remains undetermined. We show that upon ligand binding, the TNF superfamily receptor FN14 recruits a cIAP1-Tnf receptor-associated factor 2 (TRAF2) complex. Unlike IAP antagonists that cause rapid proteasomal degradation of cIAP1, signaling by FN14 promotes the lysosomal degradation of cIAP1-TRAF2 in a cIAP1-dependent manner. TNF-like weak inducer of apoptosis (TWEAK)/FN14 signaling nevertheless promotes the same noncanonical NF-kappaB signaling elicited by IAP antagonists and, in sensitive cells, the same autocrine TNFalpha-induced death occurs. TWEAK-induced loss of the cIAP1-TRAF2 complex sensitizes immortalized and minimally passaged tumor cells to TNFalpha-induced death, whereas primary cells remain resistant. Conversely, cIAP1-TRAF2 complex overexpression limits FN14 signaling and protects tumor cells from TWEAK-induced TNFalpha sensitization. Lysosomal degradation of cIAP1-TRAF2 by TWEAK/FN14 therefore critically alters the balance of life/death signals emanating from TNF-R1 in immortalized cells.
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Brain tumors, benign or malignant, are characterized by a very high degree of vascularization. Recent accumulating evidence suggests that during development the neuronal wiring follows the same routes as the vasculature and that these two systems may share some of the same factors for guidance. Thus, expression of dual angiogenic/neurogenic growth factors was evaluated by in situ hybridization in human primary brain tumors of three different types, i.e., astrocytomas, oligodendrogliomas, and ependymomas, of increasing grades, in relation with the grade and type of the tumor. For this evaluation we selected vascular endothelial growth factor (VEGF-A) and its receptors VEGF-R1 and VEGF-R2 and the neuropilins 1 and 2 (NRP-1 and NRP-2), which have proangiogenic properties, platelet-derived growth factor (PDGF) receptor-beta (PDGF-Rβ), which is required for the functional maturation of blood vessels, the ephrins and their Eph receptors, angiotensinogen (AGT) and thrombospondin-2 (TSP-2), which have potential antiangiogenic properties, and netrin-1 (Net-1), which regulates vascular architecture. We show that the expression of the VEGF-NRP system, PDGF-Rβ, TSP-2, AGT, and Net-1 are differentially regulated, either increased or decreased, in relation with the type and grade of the tumor, whereas regulation of the ephrinB system does not seem to be relevant in these human brain tumors.
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Copy number variation (CNV) has recently gained considerable interest as a source of genetic variation likely to play a role in phenotypic diversity and evolution. Much effort has been put into the identification and mapping of regions that vary in copy number among seemingly normal individuals in humans and a number of model organisms, using bioinformatics or hybridization-based methods. These have allowed uncovering associations between copy number changes and complex diseases in whole-genome association studies, as well as identify new genomic disorders. At the genome-wide scale, however, the functional impact of CNV remains poorly studied. Here we review the current catalogs of CNVs, their association with diseases and how they link genotype and phenotype. We describe initial evidence which revealed that genes in CNV regions are expressed at lower and more variable levels than genes mapping elsewhere, and also that CNV not only affects the expression of genes varying in copy number, but also have a global influence on the transcriptome. Further studies are warranted for complete cataloguing and fine mapping of CNVs, as well as to elucidate the different mechanisms by which they influence gene expression.
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BACKGROUND: As the long-term survival of pancreatic head malignancies remains dismal, efforts have been made for a better patient selection and a tailored treatment. Tumour size could also be used for patient stratification. METHODS: One hundred and fourteen patients underwent a pancreaticoduodenectomy for pancreatic adenocarcinoma, peri-ampullary and biliary cancer stratified according to: ≤20 mm, 21-34 mm, 35-45 mm and >45 mm tumour size. RESULTS: Patients with tumour sizes of ≤20 mm had a N1 rate of 41% and a R1/2 rate of 7%. The median survival was 3.4 years. N1 and R1/2 rates increased to 84% and 31% for tumour sizes of 21-34 mm (P = 0.0002 for N, P = 0.02 for R). The median survival decreased to 1.6 years (P = 0.0003). A further increase in tumour size of 35-45 mm revealed a further increase of N1 and R1/2 rates of 93% (P < 0.0001) and 33%, respectively. The median survival was 1.2 years (P = 0.004). Tumour sizes >45 mm were related to a further decreased median survival of 1.1 years (P = 0.2), whereas N1 and R1/2 rates were 87% and 20%, respectively. DISCUSSION: Tumour size is an important feature of pancreatic head malignancies. A tumour diameter of 20 mm seems to be the cut-off above which an increased rate of incomplete resections and metastatic lymph nodes must be encountered and the median survival is reduced.
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Purpose/Objective(s): Letrozole radiosensitizes breast cancer cells in vitro. In clinical settings, no data exist for the combination of letrozole and radiotherapy. We assessed concurrent and sequential radiotherapy and letrozole in the adjuvant setting.Materials/Methods: The present study is registered with ClinicalTrials.gov, number NCT00208273. This Phase 2 randomized trial was undertaken in two centers in France and one in Switzerland between January 12, 2005, and February 21, 2007. One hundred fifty postmenopausal women with early-stage breast cancer were randomly assigned after conserving surgery to either concurrent radiotherapy and letrozole (n = 75) or sequential radiotherapy and letrozole (n = 75). Randomization was open label with a minimization technique, stratified by investigational centers, chemotherapy (yes vs. no), radiation boost (yes vs. no), and value of radiation-induced lymphocyte apoptosis (#16% vs. .16%). The whole breast was irradiated to a total dose of 50 Gy in 25 fractions over 5 weeks. In the case of supraclavicular and internal mammary node irradiation, the dose was 44 - 50 Gy. Letrozole was administered orally once daily at a dose of 2 - 5 mg for 5 years (beginning 3 weeks pre-radiotherapy in the concomitant group, and 3 weeks postradiotherapy in the sequential group). The primary endpoint was the occurrence of acute (during and within 6 weeks of radiotherapy) and late (within 2 years) radiation-induced Grade 2 or worse toxic effects of the skin and lung (functional pulmonary test and lung CT-scan). Analyses were by intention-to-treat. The long-term follow-up after 2 years was only performed in Montpellier (n = 121) and evaluated skin toxicity (clinical examination every 6 months), lung fibrosis (one CT-scan yearly), cosmetic outcome.Results: All patients were analyzed apart from 1 in the concurrent group who withdrew consent before any treatment.Within the first 2 years (n = 149), no lung toxicity was identified by CT scan and no modification from baseline was noted by the lung diffusion capacity test. Two patients in each group had Grade 2 or worse late effects (both radiation-induced subcutaneous fibrosis [RISF]). After 2 years (n = 121), and with a median follow-up of 50 months (38-62), 2 patients (1 in each arm) presented a Grade 3 RISF. No lung toxicity was identified by CT scan. Cosmetic results (photographies) and quality of life was good to excellent. All patients who had Grade 3 subcutaneous fibrosis had an RILA value of 16% or less, irrespective of the sequence with letrozole.Conclusions:With long-term follow-up, letrozole can be safely delivered shortly after surgery and concomitantly with radiotherapy.
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Objective: Despite progress during recent decades, long-term outcome¦of patients with pancreatic cancer remains dismal. Since positive resection¦margins and metastatic lymph nodes are known risk factors for early tumor¦recurrence, patients at risk should be identified and could potentially benefit¦from preoperative radio-chemotherapy. This study aimed to assess whether the¦presence of lymph node metastasis could be used to predict positive resection¦margins in patients with pancreatic cancer.¦Methods: A series of 146 patients (82 male, 64 female, median age 68 years)¦underwent pancreatic head resection for various malignant diseases (pancreatic¦ductal adenocarcinoma, biliary cancer, periampullary cancer) at our institution¦from 2000 to 2011. Patients were identified from our prospective database¦that collects more than 60 single items of all patients undergoing pancreatic¦resection. Lymph node metastasis and positive resection margins were all¦confirmed by histological evaluation. Positive predictive value (PPV), negative¦predictive value (NPV), sensitivity and specificity were calculated to assess¦the predictive value of metastatic lymph nodes regarding tumor-free (R0) and¦tumor-involved (R1) resection margins.¦Results: There were 110 specimens (76%) with tumor-positive lymph nodes¦and 36 specimens with tumor-negative lymph nodes. Resection margins were¦positive in 47 specimens (32%) and negative in 99 specimens. Sensitivity of¦tumor-positive lymph nodes to detect positive resection margins was 96%, and¦the NPV was 94%. In contrast, specificity was 34% and the PPV was 41%.¦Conclusion: Patients with resectable pancreatic cancer, who have no lymph¦node metastasis, are at very low risk to have positive resection margins (2 of¦36 patients, NPV 94%). In contrast, more than one third of patients with¦metastatic lymph nodes are at increased risk for an incomplete tumor resection¦(sensitivity 96%). If lymph nodesmetastases are highly suspected at preoperative¦staging, a neoadjuvant treatment strategy should be considered to increase the¦R0 resection rate.
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BACKGROUND: Switzerland is a region in which alveolar echinococcosis (AE) is endemic. Studies evaluating outcomes after liver resection (LR) for AE are scarce. The aim of this study was to assess the short- and long-term outcomes of AE patients after LR in a single tertiary referral center. METHODS: We retrospectively analyzed data pertaining to all patients with liver AE who were treated with LR at our institution between January 1992 and December 2013. Patient demographics, intraoperative data, extent of LR procedures (major vs. minor LR), postoperative outcomes, and negative histological margin (R0) resection rate were recorded in a database. Recurrence rates after LR were analyzed. RESULTS: LR was performed in 59 patients diagnosed with hepatic AE (56 complete surgeries, 3 reduction surgeries). Postoperative morbidity and mortality were observed in 34 % (25 % grade I-II, 9 % grade III-IV) and 2 % of the patients, respectively. R0 (complete) resection rate was 71 % (n = 42), and R1/R2 resection rate was 29 % (n = 17). Extra-hepatic recurrence occurred in 1 case (lung) after R0 resection. In cases of R1/R2 resection, 7 intra-hepatic disease progressions occurred with a median time of 10 months (IQR 6-11 months). Long-term (more than 1 year) benzimidazole treatment stabilized the disease in 64 % (9/14) of patients with R1 status. The overall survival rate was 97 %. CONCLUSIONS: Liver AE can be safely and definitively treated with LR, provided that R0 resection is achieved. In cases of R1 resection, benzimidazole therapy seems to be effective in stabilizing the intra-hepatic disease and preventing extra-hepatic recurrence.
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Aim: We have previously documented the feasibility of neoadjuvant chemotherapy and EPP in a multicenter trial of MPM (Weder, Ann Oncol 18: 1196, 2007). The objectives of the trimodality trial SAKK17/04 (NCT00334594) were to evaluate the time to loco-regional relapse with or without high dose hemithoracic radiotherapy in a prospective multicenter randomized phase II trial in patients with R0 and R1 resection after neoadjuvant chemotherapy and EPP. Methods: Eligible patients had pathologically confirmed MPM, surgically resectable TNM stage (T1-3 N0-2 M0), PS0-1, ages 18-70 years. Part 1 had a phase II design, and included neoadjuvant chemotherapy with 3 cycles of cisplatin and pemetrexed, followed by restaging and EPP. The primary endpoint of part 1 was complete macroscopic resection (R0-1). Part 2 randomized consenting patients with R0-1 resection into two parallel phase II arms (control arm A and radiotherapy arm B). The primary endpoint for part 2 was loco-regional relapse-free survival (RFS). To detect a 1 year increase with 80% power and 10% alpha, 37 patients were needed for arm B. Secondary endpoints included operability, tolerability of chemotherapy and radiotherapy, survival, and translational research Results: Because accrual of part 2 was slower than planned, the trial was stopped in 2013. Overall, 153 patients entered the trial, of whom 125 underwent surgery and 99 had a complete macroscopic resection (primary endpoint part 1). Of the later patients, 54 could be randomized 1:1 into each arm. Reasons for non-randomization included patient refusal in 24 and ineligibility or protocol deviations in 21. Of the 27 patients randomized to hemithoracic radiotherapy, 25 completed the treatment as planned. For part 1 the median RFS was 8.8 (95%CI: 7.3-10.7) and median OS was 15.0 (95% CI: 12.1-19.3) months. For part 2 the median local RFS for group A was 7.6 (95%CI: 5.5-10.7) and for group B 9.4 (95%CI: 6.5-11.9) months (primary endpoint part 2), while the overall RFS and OS for group A were 5.7 (95%CI: 3.5-8.8) and 16.9 (95%CI: 10.7-23.6) months and for group B 7.6 (95% CI:5.2-10.6) and 14.9 (95%CI: 7.0-17.6) months. Conclusions: This study did not reach the primary endpoint which was defined as one-year increase in loco-regional relapse-free survival and thus does not support the routine use of hemithoracic RT after neoadjuvant chemotherapy and EPP. Disclosure: All authors have declared no conflicts of interest.