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1.
Cartilage ; : 19476035231191202, 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37723972

RESUMO

OBJECTIVE: This study was conducted to assess the effect of osteochondroplasty on osteoarthritis (OA) prevention, comparing radiological evolution between identical hips from the same patient who had undergone unilateral surgery. DESIGN: We retrospectively reviewed radiological evolution between hips with similar shape from the same patient who had undergone unilateral surgery. In all, 56 FAI patients (112 hips) with a mean age of 42.18 ± 9.16 years and had undergone unilateral arthroscopy treatment have been included. Four independent researchers measured Wiberg, Acetabular and Alpha angles, Extrusion index, and Tönnis classification preoperatively to verify that operated and non-operated hips had the same shape. OA evolution was assessed by joint space width (JSW) in 3 different articular points and Tönnis classification. RESULTS: No preoperative anatomical differences were present between groups (P > 0.05). At the end of follow-up (31.9 months), a decrease of JSW in the 3 points measured was found in OP hips (OP vs. N-OP; P < 0.01). These results were correlated with changes in the proportion of patients who progressed to grade III in Tönnis classification (from 1.3% preoperative to 23.2% at the end of follow-up). CONCLUSIONS: Osteochondroplasty and labrum procedures were not associated with OA prevention. The OP hips showed a faster OA degeneration, which was not seen in the N-OP. These results will encourage hip surgeons to perform further investigations to avoid the "Pandora's Box Opening Process."

2.
Bone Joint J ; 105-B(1): 11-16, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36587257

RESUMO

Paediatric bone sarcomas are a dual challenge for orthopaedic surgeons in terms of tumour resection and reconstruction, as it is important to minimize functional and growth problems without compromising survival rates. Cañadell's technique consists of a Type I epiphysiolysis performed using continuous distraction by an external fixator prior to resection. It was designed to achieve a safe margin due to the ability of the physeal cartilage to be a barrier to tumour spread in some situations, avoiding the need for articular reconstruction, and preserving the growth capacity most of the times. Despite initial doubts raised in the scientific community, this technique is now widely used in many countries for the treatment of metaphyseal paediatric bone sarcomas. This annotation highlights the importance of Cañadell's work and reviews the experience of applying it to bone sarcoma patients over the last 40 years.Cite this article: Bone Joint J 2023;105-B(1):11-16.


Assuntos
Neoplasias Ósseas , Osteogênese por Distração , Osteossarcoma , Sarcoma , Criança , Humanos , Osteossarcoma/cirurgia , Neoplasias Ósseas/patologia , Fixadores Externos , Osteogênese por Distração/métodos
3.
Nat Commun ; 13(1): 7619, 2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36494342

RESUMO

Myelodysplastic syndromes (MDS) are hematopoietic stem cell (HSC) malignancies characterized by ineffective hematopoiesis, with increased incidence in older individuals. Here we analyze the transcriptome of human HSCs purified from young and older healthy adults, as well as MDS patients, identifying transcriptional alterations following different patterns of expression. While aging-associated lesions seem to predispose HSCs to myeloid transformation, disease-specific alterations may trigger MDS development. Among MDS-specific lesions, we detect the upregulation of the transcription factor DNA Damage Inducible Transcript 3 (DDIT3). Overexpression of DDIT3 in human healthy HSCs induces an MDS-like transcriptional state, and dyserythropoiesis, an effect associated with a failure in the activation of transcriptional programs required for normal erythroid differentiation. Moreover, DDIT3 knockdown in CD34+ cells from MDS patients with anemia is able to restore erythropoiesis. These results identify DDIT3 as a driver of dyserythropoiesis, and a potential therapeutic target to restore the inefficient erythroid differentiation characterizing MDS patients.


Assuntos
Síndromes Mielodisplásicas , Fatores de Transcrição , Adulto , Humanos , Idoso , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Síndromes Mielodisplásicas/patologia , Eritropoese/genética , Células-Tronco Hematopoéticas/metabolismo , Regulação da Expressão Gênica , Fator de Transcrição CHOP/genética
4.
Diagnostics (Basel) ; 12(5)2022 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-35626284

RESUMO

Objective: The aim of the study is to describe the morphology associated with the development of osteoarthritis (OA) in three different age groups. These data will contribute to defining the morphology associated with early and late hip OA. Methods: We studied 400 hips in 377 patients who had undergone primary THA due to idiopathic OA. Three groups were compared: group 1 (n = 147), younger patients, aged up to 60 years; group 2 (n = 155), patients aged between 61 and 74 years; and group 3 (n = 98), aged 75 or over. Five independent researchers measured the hip angles and the mean values were used to build a database. Results: No differences between groups in sex distribution and BMI were detected. Less coverage of the head (extrusion index), higher Tönnis angle, lower Wiberg and alpha angles characterized early OA hips. These differences increased with age, being greater between group 2 and group 3 (p < 0.01). However, significant differences were still present in the comparison between group 1 and group 2 (p < 0.01)). No differences were detected between group 2 and group 3. Conclusion: Elevated acetabular angle, head extrusion and decreased Wiberg angle characterize hip osteoarthritis at younger ages and should be the focus of hip preservation surgery in terms of osteoarthritis prevention. Pincer-type FAI (higher Wiberg and lower Tönnis angle) and higher alpha angle (CAM) are correlated with the development of later OA. These results shed doubt on applying the hip preservation surgery concept in terms of osteoarthritis prevention in FAI, especially in Pincer-type FAI patients.

5.
Cancers (Basel) ; 13(21)2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34771600

RESUMO

Genomic techniques enable diagnosis and management of children and young adults with sarcomas by identifying high-risk patients and those who may benefit from targeted therapy or participation in clinical trials. Objective: to analyze the performance of an NGS gene panel for the clinical management of pediatric sarcoma patients. We studied 53 pediatric and young adult patients diagnosed with sarcoma, from two Spanish centers. Genomic data were obtained using the Oncomine Childhood Cancer Research Assay, and categorized according to their diagnostic, predictive, or prognostic value. In 44 (83%) of the 53 patients, at least one genetic alteration was identified. In 80% of these patients, the diagnosis was obtained (n = 11) or changed (n = 9), and thus genomic data affected therapy. The most frequent initial misdiagnosis was Ewing's sarcoma, instead of myxoid liposarcoma (FUS-DDDIT3), rhabdoid soft tissue tumor (SMARCB1), or angiomatoid fibrous histiocytoma (EWSR1-CREB1). In our series, two patients had a genetic alteration with an FDA-approved targeted therapy, and 30% had at least one potentially actionable alteration. NGS-based genomic studies are useful and feasible in diagnosis and clinical management of pediatric sarcomas. Genomic characterization of these rare and heterogeneous tumors also helps in the search for prognostic biomarkers and therapeutic opportunities.

6.
J Child Orthop ; 15(4): 322-330, 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34476021

RESUMO

PURPOSE: The main challenge in reconstruction after malignant bone tumour resection in young children remains how and when growth-plates can be preserved and which options remain if impossible. METHODS: We describe different strategies to assure best possible long-term function for young children undergoing resection of malignant bone tumours. RESULTS: Different resources are available to treat children with malignant bones tumours: a) preoperative planning simulates scenarios for tumour resection and limb reconstruction, facilitating decision-making for surgical and reconstructive techniques in individual patients; b) allograft reconstruction offers bone-stock preservation for future needs. Most allografts are intact at long-term follow-up, but limb-length inequalities and corrective/revision surgery are common in young patients; c) free vascularized fibula can be used as stand-alone reconstruction, vascularized augmentation of structural allograft or devitalized autograft. Longitudinal growth and joint remodelling potential can be preserved, if transferred with vascularized proximal physis; d) epiphysiolysis before resection with continuous physeal distraction provides safe resection margins and maintains growth-plate and epiphysis; e) 3D printing may facilitate joint salvage by reconstruction with patient-specific instruments. Very short stems can be created for fixation in (epi-)metaphysis, preserving native joints; f) growing endoprosthesis can provide for remaining growth after resection of epi-metaphyseal tumours. At ten-year follow-up, limb survival was 89%, but multiple surgeries are often required; g) rotationplasty and amputation should be considered if limb salvage is impossible and/or would result in decreased function and quality of life. CONCLUSION: Several biological and technological reconstruction options must be merged and used to yield best outcomes when treating young children with malignant bone tumours. LEVEL OF EVIDENCE: Level V Expert opinion.

7.
Materials (Basel) ; 12(19)2019 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-31554158

RESUMO

In the treatment of bone non-unions, an alternative to bone autografts is the use of bone morphogenetic proteins (BMPs), e.g., BMP-2, BMP-7, with powerful osteoinductive and osteogenic properties. In clinical settings, these osteogenic factors are applied using absorbable collagen sponges for local controlled delivery. Major side effects of this strategy are derived from the supraphysiological doses of BMPs needed, which may induce ectopic bone formation, chronic inflammation, and excessive bone resorption. In order to increase the efficiency of the delivered BMPs, we designed cryostructured collagen scaffolds functionalized with hydroxyapatite, mimicking the structure of cortical bone (aligned porosity, anisotropic) or trabecular bone (random distributed porosity, isotropic). We hypothesize that an anisotropic structure would enhance the osteoconductive properties of the scaffolds by increasing the regenerative performance of the provided rhBMP-2. In vitro, both scaffolds presented similar mechanical properties, rhBMP-2 retention and delivery capacity, as well as scaffold degradation time. In vivo, anisotropic scaffolds demonstrated better bone regeneration capabilities in a rat femoral critical-size defect model by increasing the defect bridging. In conclusion, anisotropic cryostructured collagen scaffolds improve bone regeneration by increasing the efficiency of rhBMP-2 mediated bone healing.

8.
J Tissue Eng Regen Med ; 13(5): 742-752, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30785671

RESUMO

An attractive alternative to bone autografts is the use of autologous mesenchymal progenitor cells (MSCs) in combination with biomaterials. We compared the therapeutic potential of different sources of mesenchymal stem cells in combination with biomaterials in a bone nonunion model. A critical-size defect was created in Sprague-Dawley rats. Animals were divided into six groups, depending on the treatment to be applied: bone defect was left empty (CTL); treated with live bone allograft (LBA); hrBMP-2 in collagen scaffold (CSBMP2 ); acellular polycaprolactone scaffold (PCL group); PCL scaffold containing periosteum-derived MSCs (PCLPMSCs ) and PCL containing bone marrow-derived MSCs (PCLBMSCs ). To facilitate cell tracking, both MSCs and bone graft were isolated from green fluorescent protein (GFP)-transgenic rats. CTL group did not show any signs of healing during the radiological follow-up (n = 6). In the LBA group, all the animals showed bone bridging (n = 6) whereas in the CSBMP2 group, four out of six animals demonstrated healing. In PCL and PCLPMSCs groups, a reduced number of animals showed radiological healing, whereas no healing was detected in the PCLBMSCs group. Using microcomputed tomography, the bone volume filling the defect was quantified, showing significant new bone formation in the LBA, CSBMP2 , and PCLPMSCs groups when compared with the CTL group. At 10 weeks, GFP positive cells were detected only in the LBA group and restricted to the outer cortical bone in close contact with the periosteum. Tracking of cellular implants demonstrated significant survival of the PMSCs when compared with BMSCs. In conclusion, PMSCs improve bone regeneration being suitable for mimetic autograft design.


Assuntos
Bioprótese , Fraturas do Fêmur/terapia , Consolidação da Fratura , Células-Tronco Mesenquimais/metabolismo , Periósteo/metabolismo , Engenharia Tecidual , Animais , Fraturas do Fêmur/metabolismo , Fraturas do Fêmur/patologia , Células-Tronco Mesenquimais/patologia , Periósteo/patologia , Ratos , Ratos Sprague-Dawley
9.
J Transl Med ; 14(1): 246, 2016 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-27565858

RESUMO

BACKGROUND: Mesenchymal stromal cells are a promising option to treat knee osteoarthritis. Their safety and usefulness must be confirmed and the optimal dose established. We tested increasing doses of bone marrow mesenchymal stromal cells (BM-MSCs) in combination with hyaluronic acid in a randomized clinical trial. MATERIALS: A phase I/II multicenter randomized clinical trial with active control was conducted. Thirty patients diagnosed with knee OA were randomly assigned to intraarticularly administered hyaluronic acid alone (control), or together with 10 × 10(6) or 100 × 10(6) cultured autologous BM-MSCs, and followed up for 12 months. Pain and function were assessed using VAS and WOMAC and by measuring the knee motion range. X-ray and magnetic resonance imaging analyses were performed to analyze joint damage. RESULTS: No adverse effects were reported after BM-MSC administration or during follow-up. BM-MSC-administered patients improved according to VAS during all follow-up evaluations and median value (IQR) for control, low-dose and high-dose groups change from 5 (3, 7), 7 (5, 8) and 6 (4, 8) to 4 (3, 5), 2 (1, 3) and 2 (0,4) respectively at 12 months (low-dose vs control group p = 0.005 and high-dose vs control group p < 0.009). BM-MSC-administered patients were also superior according to WOMAC, although improvement in control and low-dose patients could not be significantly sustained beyond 6 months. On the other hand, the BM-MSC high-dose group exhibited an improvement of 16.5 (12, 19) points at 12 months (p < 0.01). Consistent with WOMAC and VAS values, motion ranges remained unaltered in the control group but improved at 12 months with BM-MSCs. X-ray revealed a reduction of the knee joint space width in the control group that was not seen in BM-MSCs high-dose group. MRI (WORMS protocol) showed that joint damage decreased only in the BM-MSC high-dose group, albeit slightly. CONCLUSIONS: The single intraarticular injection of in vitro expanded autologous BM-MSCs together with HA is a safe and feasible procedure that results in a clinical and functional improvement of knee OA, especially when 100 × 10(6) cells are administered. These results pave the way for a future phase III clinical trial. CLINICAL TRIALS: gov identifier NCT02123368. Nº EudraCT: 2009-017624-72.


Assuntos
Ácido Hialurônico/administração & dosagem , Ácido Hialurônico/farmacologia , Transplante de Células-Tronco Mesenquimais , Osteoartrite do Joelho/terapia , Idoso , Terapia Combinada , Demografia , Feminino , Humanos , Ácido Hialurônico/efeitos adversos , Injeções Intra-Articulares , Imageamento por Ressonância Magnética , Masculino , Transplante de Células-Tronco Mesenquimais/efeitos adversos , Pessoa de Meia-Idade , Osteoartrite do Joelho/diagnóstico por imagem , Osteoartrite do Joelho/patologia , Osteoartrite do Joelho/fisiopatologia , Amplitude de Movimento Articular/efeitos dos fármacos , Resultado do Tratamento , Escala Visual Analógica
10.
Stem Cells ; 34(9): 2342-53, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27250101

RESUMO

Fracture nonunion is a major complication of bone fracture regeneration and repair. The molecular mechanisms that result in fracture nonunion appearance are not fully determined. We hypothesized that fracture nonunion results from the failure of hypoxia and hematoma, the primary signals in response to bone injury, to trigger Bmp2 expression by mesenchymal progenitor cells (MSCs). Using a model of nonstabilized fracture healing in transgenic 5'Bmp2BAC mice we determined that Bmp2 expression appears in close association with hypoxic tissue and hematoma during the early phases of fracture healing. In addition, BMP2 expression is induced when human periosteum explants are exposed to hypoxia ex vivo. Transient interference of hypoxia signaling in vivo with PX-12, a thioredoxin inhibitor, results in reduced Bmp2 expression, impaired fracture callus formation and atrophic-like nonunion by a HIF-1α independent mechanism. In isolated human periosteum-derived MSCs, BMP2 expression could be induced with the addition of platelets concentrate lysate but not with hypoxia treatment, confirming HIF-1α-independent BMP2 expression. Interestingly, in isolated human periosteum-derived mesenchymal progenitor cells, inhibition of BMP2 expression by PX-12 is accomplished only under hypoxic conditions seemingly through dis-regulation of reactive oxygen species (ROS) levels. In conclusion, we provide evidence of a molecular mechanism of hypoxia-dependent BMP2 expression in MSCs where interference with ROS homeostasis specifies fracture nonunion-like appearance in vivo through inhibition of Bmp2 expression. Stem Cells 2016;34:2342-2353.


Assuntos
Fraturas não Consolidadas/metabolismo , Fraturas não Consolidadas/patologia , Homeostase , Células-Tronco Mesenquimais/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Proteína Morfogenética Óssea 2/metabolismo , Hipóxia Celular/efeitos dos fármacos , Separação Celular , Dissulfetos/farmacologia , Consolidação da Fratura/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Imidazóis/farmacologia , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Osteogênese/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Periósteo/patologia
11.
Radiother Oncol ; 119(1): 91-6, 2016 04.
Artigo em Inglês | MEDLINE | ID: mdl-26900090

RESUMO

BACKGROUND AND PURPOSE: To demonstrate the feasibility, safety and effectiveness of dose escalation to intraprostatic lesions with MRI-transrectal ultrasound fusion High-Dose-Rate (HDR) brachytherapy. MATERIALS AND METHODS: 15 patients with intermediate-high risk prostate cancer and visible dominant intra-prostatic nodule on mpMRI have been treated. The treatment consisted of combined MRI-TRUS fusion HDR-brachytherapy (1 fraction of 1500cGy) and hypofractionated external beam (3750cGy in 15 fractions). A dose of 1875Gy was delivered to at least 98% of the DIL volume. RESULTS: Median prostate volume was 23.8cc; median number of needles was 16 (13-18). Dose escalation to DIL was feasible in 14/15 patients (93%) without violating dosimetric constraints and 1 patient presented a minimal deviation of dosimetric restrictions. With a median follow-up of 18months (17-24), none of the patients developed acute urinary retention or grade ⩾3 toxicity. In addition to standard PSA follow-up, response has been assessed by mpMRI at 12months. All patients presented adequate morphological responses on anatomical and functional sequences. CONCLUSIONS: HDR brachytherapy using MRI-transrectal ultrasound fusion for image guidance is a suitable technique for partial prostate dose escalation. Tolerance and toxicity profiles are excellent and results are encouraging in terms of biochemical, morphological and functional response.


Assuntos
Braquiterapia/métodos , Imageamento por Ressonância Magnética/métodos , Neoplasias da Próstata/radioterapia , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Dosagem Radioterapêutica , Ultrassonografia de Intervenção
12.
Eur J Nucl Med Mol Imaging ; 42(9): 1378-89, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25952280

RESUMO

PURPOSE: The objective of this study was to determine the incremental staging information provided by positron emission tomography/computed tomography (PET/CT) and its impact on management plans in patients with untreated stage III-IV head and neck squamous cell carcinoma (HNSCC). METHODS: We prospectively studied, between September 2011 and February 2013, 84 consecutive patients [median age 63.5 years (39-84); 73 men] with histologically confirmed HNSCC. First, based on a conventional work-up (physical examination, CT imaging of the head, neck and chest), the multidisciplinary Head and Neck Tumour Board documented the TNM stage and a management plan for each patient, outlining the modalities to be used, including surgery, radiation therapy (RT), chemotherapy or a combination. After release of the PET/CT results, new TNM staging and management plans were agreed on by the multidisciplinary Tumour Board. Any changes in stage or intended management due to the PET/CT findings were then analysed. The impact on patient management was classified as: low (treatment modality, delivery and intent unchanged), moderate (change within the same treatment modality: type of surgery, radiation technique/dose) or high (change in treatment intent and/or treatment modality → curative to palliative, or surgery to chemoradiation or detection of unknown primary tumour or a synchronous second primary tumour). TNM stage was validated by histopathological analysis, additional imaging or follow-up. Accuracy of the conventional and PET/CT-based staging was compared using McNemar's test. RESULTS: Conventional and PET/CT stages were discordant in 32/84 (38 %) cases: the T stage in 2/32 (6.2 %), the N stage in 21/32 (65.7 %) and the M stage 9/32 (28.1 %). Patient management was altered in 22/84 (26 %) patients, with a moderate impact in 8 (9.5 %) patients and high impact in 14 (16.6 %) patients. PET/CT TNM classification was significantly more accurate (92.5 vs 73.7 %) than conventional staging with a p value < 0.001 (McNemar's test). CONCLUSION: PET/CT should be implemented in the routine imaging work-up of stage III-IV HNSCC.


Assuntos
Carcinoma de Células Escamosas/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Imagem Multimodal , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/terapia , Feminino , Fluordesoxiglucose F18 , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Prospectivos , Sensibilidade e Especificidade
13.
BMC Plant Biol ; 9: 75, 2009 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-19545370

RESUMO

BACKGROUND: Transcription factor HaDREB2 was identified in sunflower (Helianthus annuus L.) as a drought-responsive element-binding factor 2 (DREB2) with unique properties. HaDREB2 and the sunflower Heat Shock Factor A9 (HaHSFA9) co-activated the Hahsp17.6G1 promoter in sunflower embryos. Both factors could be involved in transcriptional co-activation of additional small heat stress protein (sHSP) promoters, and thus contribute to the HaHSFA9-mediated enhancement of longevity and basal thermotolerance of seeds. RESULTS: We found that overexpression of HaDREB2 in seeds did not enhance longevity. This was deduced from assays of basal thermotolerance and controlled seed-deterioration, which were performed with transgenic tobacco. Furthermore, the constitutive overexpression of HaDREB2 did not increase thermotolerance in seedlings or result in the accumulation of HSPs at normal growth temperatures. In contrast, when HaDREB2 and HaHSFA9 were conjointly overexpressed in seeds, we observed positive effects on seed longevity, beyond those observed with overexpression of HaHSFA9 alone. Such additional effects are accompanied by a subtle enhancement of the accumulation of subsets of sHSPs belonging to the CI and CII cytosolic classes. CONCLUSION: Our results reveal the functional interdependency of HaDREB2 and HaHSFA9 in seeds. HaDREB2 differs from other previously characterized DREB2 factors in plants in terms of its unique functional interaction with the seed-specific HaHSFA9 factor. No functional interaction between HaDREB2 and HaHSFA9 was observed when both factors were conjointly overexpressed in vegetative tissues. We therefore suggest that additional, seed-specific factors, or protein modifications, could be required for the functional interaction between HaDREB2 and HaHSFA9.


Assuntos
Proteínas de Choque Térmico/metabolismo , Helianthus/fisiologia , Proteínas de Plantas/metabolismo , Sementes/fisiologia , Fatores de Transcrição/metabolismo , Desidratação , Regulação da Expressão Gênica de Plantas , Proteínas de Choque Térmico/genética , Helianthus/genética , Temperatura Alta , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/fisiologia , Sementes/genética , Fatores de Transcrição/genética
14.
Sarcoma ; 2009: 827912, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20066170

RESUMO

Introduction. The aim of this study is to compare outcomes in three groups of STS patients treated in our specialist centre: patients referred immediately after an inadequate initial treatment, patients referred after a local recurrence, and patients referred directly, prior to any treatment. Patients and methods. We reviewed all our nonmetastatic extremity-STS patients with a minimum follow-up of 2 years. We compared three patient groups: those referred directly to our centre (group A), those referred after an inadequate initial excision (group B), and patients with local recurrence (group C). Results. The study included 174 patients. Disease-free survival was 73%, 76%, and 28% in groups A, B, and C, respectively (P < .001). Depth, size, and histologic grade influenced the outcome in groups A and B, but not in C. Conclusion. Initial wide surgical treatment is the main factor that determines local control, being even more important than the known intrinsic prognostic factors of tumour size, depth, and histologic grade. The influence on outcome of initial wide local excision (WLE), which is made possible by referral to a specialist centre, is paramount.

15.
Plant Physiol ; 139(3): 1483-94, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16244139

RESUMO

Hahsp17.6G1 is the promoter of a small heat stress protein (sHSP) from sunflower (Helianthus annuus) that is activated during zygotic embryogenesis, but which does not respond to heat stress. We report here the cloning of a transcription factor (TF), sunflower drought-responsive element binding factor 2 (HaDREB2), by one-hybrid interaction with functional cis-elements in Hahsp17.6G1. We have analyzed the functional interaction between HaDREB2 and a second transcription factor, sunflower heat stress factor A9 (HaHSFA9), which was previously assigned to the regulation of Hahsp17.6G1. HaDREB2 and HaHSFA9 synergistically trans-activate the Hahsp17.6G1 promoter in bombarded sunflower embryos. This synergistic interaction is heat stress factor (HSF) specific and requires the binding of both factors to the promoter. The C-terminal region of HaHSFA9 is sufficient for the HSF specificity. Our results represent an example of a functional interaction between members of the Apetala 2 (HaDREB2) and HSF (HaHSFA9) families of transcription factors. We suggest new roles in zygotic embryogenesis for specific members of the AP2 transcription factor family.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Choque Térmico/metabolismo , Helianthus/genética , Proteínas de Plantas/genética , Regiões Promotoras Genéticas/genética , Fatores de Transcrição/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Regulação da Expressão Gênica no Desenvolvimento , Fatores de Transcrição de Choque Térmico , Proteínas de Choque Térmico/química , Proteínas de Choque Térmico/genética , Helianthus/embriologia , Dados de Sequência Molecular , Mutação/genética , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Ligação Proteica , Elementos Reguladores de Transcrição/genética , Nicotiana/genética , Fatores de Transcrição/química , Fatores de Transcrição/genética , Ativação Transcricional/genética , Técnicas do Sistema de Duplo-Híbrido
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