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INTRODUCTION: Male breast cancer is rare and accounts for less than 1% of all breast cancer cases worldwide. METHODS: This retrospective cohort study included all patients of invasive male breast cancer treated with curative intent by a trimodality approach via a multidisciplinary team at an academic university hospital in India between 2009 and 2023. Records were identified from a prospectively maintained database. Clinicopathological parameters, treatment details and survival were recorded and analysed. RESULTS: Thirty-four patients were included. The median (IQR) age was 55(44-63) years. Most patients were overall stage III (74%) and node positive (79%) with Scarff-Bloom-Richardson grade II (50%). Twenty-five patients (73%) were oestrogen receptor (ER) positive. Lymphovascular space invasion (LVSI) and perineural invasion (PNI) were present in 62% and 21% of patients, respectively. The most common chemotherapy timing was adjuvant (53%) followed by neoadjuvant (41%), and the most commonly used regimen consisted of a combination of doxorubicin-cyclophosphamide followed by a taxane (53%). Most (85%) patients underwent a mastectomy, five patients underwent breast conservation. All patients received radiotherapy to a dose of 42.6 Gy in 16 fractions, followed by a tumour bed boost for those undergoing breast conservation. At a median follow-up of 70 months (range 10-159 months), the five and ten-year overall survival was 91% and 58%, and the five-year disease-free survival (DFS) was 67%. The median DFS was 72 months. On univariate analysis, the tumour sub-type (Luminal versus TNBC) significantly predicted DFS (P = 0.03 log-rank). CONCLUSION: Breast cancer in males has a high incidence of node positivity, ER positivity and LVSI. Even with advanced stages at presentation, trimodality therapy in a multidisciplinary setting offers good long-term outcomes.
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OBJECTIVE: Dosimetric sparing of critical swallowing structures like constrictor muscles and larynx can lead to improved functional outcomes in head and neck cancer patients treated by chemoradiation. METHODS: A total of 50 Patients with newly diagnosed, biopsy proven AJCC stage II-IV head and neck squamous cell cancers (HNSCC) were prospectively studied. 25 patients were randomized in each arm of Dysphagia-optimized Intensity Modulated Radiotherapy (Do-IMRT) arm and Standard Intensity Modulated Radiotherapy (SIMRT) arm. Additional dose constraints were applied to the dysphagia/aspiration at risk structures (DARS) in Do-IMRT arm. The impact of using Do-IMRT was assessed by the difference in mean scores of MD Anderson Dysphagia Inventory (MDADI), University of Washington-Quality of Life (UW-QOL), and 100 ml Water Swallow Test (WST). RESULTS: Patients in both arms showed significant (P <0.01 or P < 0.001) improvement in MDADI (global and composite), UW-QOL and Water Swallow Test scores. However, the improvements were found significantly higher in Do-IMRT as compared to S-IMRT. Significant improvements i.e. mean change from baseline to 12 months (P <0.05 or P <0.01 or P <0.001) were 19. 2, 8.6, 14.3, 7.4, 18.6 and 22.0% higher respectively in Do-IMRT as compared to S-IMRT in MDADI global and composite scores, UW-QOL swallowing scores, and 100 ml Water Swallow (swallowing volume, swallowing capacity and swallowing speed) test scores. CONCLUSION: The Do-IMRT improves swallowing functions compared to S-IMRT in HNSCC patients treated with radical chemoradiation.
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Transtornos de Deglutição , Neoplasias de Cabeça e Pescoço , Radioterapia de Intensidade Modulada , Humanos , Transtornos de Deglutição/etiologia , Carcinoma de Células Escamosas de Cabeça e Pescoço , Qualidade de Vida , Neoplasias de Cabeça e Pescoço/radioterapia , ÁguaRESUMO
BACKGROUND: In cervical cancer treatment, overall treatment time (OTT) is an important prognostic factor. This study compares the clinical outcomes when High-Dose-Rate Intracavitary-Brachytherapy(HDR-ICRT) is interdigitated with external beam radiotherapy(EBRT) versus sequential HDR-ICRT after EBRT in the treatment of locally advanced carcinoma cervix. METHODS: Histologically confirmed carcinoma cervix patients [FIGO Stage IIB-IVA (except IIIC-2)] were included and randomized into two groups. The study group received EBRT 50Gy in 25 fractions with interdigitated HDR-ICRT 7Gy per fraction weekly for three fractions starting after completion of 3 weeks of EBRT or as soon as cervical os became negotiable thereafter. Patients in the control group received EBRT 50Gy in 25 fractions with sequential HDR-ICRT 7Gy per fraction weekly for three fractions starting one week after completion of EBRT. All patients were regularly followed up during and after radiotherapy for local toxicity and disease control. RESULTS: This study enrolled 102 patients; 51 in each arm. Median OTT in study and control arm were 46 and 60 days, respectively. Median follow-up duration was 24 months (two years). Loco-regional control after two years of follow-up was 84.31 % and 72.54% of patients in study arm control arm respectively (p-value 0.148). Two (3.92%) patients from study arm and eight (15.68%) from control arm had residual disease. Two patients in study arm and one from control arm had local recurrence. Two patients from study arm three patients from control arm developed distant metastases. RTOG mucosal grade III acute mucosal toxicity in either arm. Cervical-os negotiability was limiting factor for interdigitated HDR-ICRT. CONCLUSIONS: Interdigitated HDR-ICRT with EBRT may give local control with manageable toxicities as compared to sequential HDR-ICRT, with the advantage of significant reduction in OTT.
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Braquiterapia , Carcinoma de Células Escamosas , Neoplasias do Colo do Útero , Feminino , Humanos , Colo do Útero/patologia , Carcinoma de Células Escamosas/patologia , Dosagem Radioterapêutica , Neoplasias do Colo do Útero/radioterapia , Neoplasias do Colo do Útero/patologiaRESUMO
Purpose: Intra-cavitary brachytherapy is an integral component of cervical cancer management, and uterine perforation is the most significant complication, which may lead to prolonged overall treatment time and decreased local control in these patients. Material and methods: A retrospective analysis of cervical cancer patients who completed radiotherapy (external beam radiotherapy and brachytherapy) in our department was conducted to determine the incidence, effect on overall treatment time, and final outcome in patients with uterine perforation during brachytherapy procedure. Results: Among 55 women, of the 398 applications, 85 (21.36%) resulted in uterine perforation. Out of these 85 applications, treatment time was extended among 3 (3.5%) applications only, as re-insertion was done nearly after one week, while the remaining 82 (96.5%) applications were completed in time. At the time of analysis, the median follow-up was 12 months, and 32 patients were disease-free, 3 had distant metastatic disease, 2 had residual disease, and 18 were lost to follow-up. Conclusions: In our study, uterine perforation incidence was found to be comparable with other centers worldwide. In asymptomatic and uncomplicated uterine perforation, treatment can be continued with computer-based optimized treatment plans without loading a specific dwell position and without affecting overall treatment time.
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Carcinoma , Neoplasias Esofágicas , Humanos , Neoplasias Esofágicas/terapia , Terapia CombinadaRESUMO
BACKGROUND: Anatomical variations in head and neck cancer during IMRT leads to volume shrinkage, results in dosimetric variations in tumour and normal tissue including parotid glands, with a risk of radiation toxicities. METHODS: 30 patients with a stage II-IV head and neck squamous cell carcinoma (HNSCC) were treated with definitive IMRT-SIB and concomitant chemotherapy. Volumetric and dosimetric variations were evaluated during the period of IMRT by recalculating and obtaining dose-volume histograms of re-contoured target volumes and parotid glands on repeat CT scans taken multiple times during treatment (CT1, CT2, CT3 and CT4). RESULTS: Result showed significant (p < 0.001) mean decrease in both primary and nodal tumors volume with time whereas increase (p < 0.01 or p < 0.001) in respective V100 (%) and D2% (Gy). The mean parotid gland dose increased (p < 0.01 or p < 0.001) with time, whereas parotid gland volume and distance between plan isocenter and centre of mass of parotid glands decreased (p < 0.05 or p < 0.001) with time. Patient's mean weight and neck circumference both decrease (p < 0.001) with time whereas ECOG score increase (p < 0.001) with time. The mucosal toxicity increased significantly (p < 0.001) with time. The change in both weight and neck circumference showed significant (p < 0.001) and direct (positive correlation) association with change in parotid gland volume. CONCLUSION: If the PTV and normal anatomy are changing with time, adaptive IMRT would be beneficial radiation dose delivery where possible.
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Neoplasias de Cabeça e Pescoço/radioterapia , Órgãos em Risco/efeitos da radiação , Glândula Parótida/efeitos da radiação , Radioterapia de Intensidade Modulada/métodos , Carcinoma de Células Escamosas de Cabeça e Pescoço/radioterapia , Carga Tumoral/efeitos da radiação , Adulto , Idoso , Peso Corporal/efeitos da radiação , Feminino , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Pescoço/anatomia & histologia , Órgãos em Risco/anatomia & histologia , Órgãos em Risco/diagnóstico por imagem , Glândula Parótida/anatomia & histologia , Glândula Parótida/diagnóstico por imagem , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/efeitos adversos , Índice de Gravidade de Doença , Carcinoma de Células Escamosas de Cabeça e Pescoço/diagnóstico por imagem , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Tomografia Computadorizada por Raios XRESUMO
The COVID-19 global pandemic has drastically affected the health care facility worldwide, posing unprecedented challenges in front of the caregivers. All hospitals need adopt measures to protect patients and health professionals and to safely triage patients (according to country/regional directives) for identifying those infected with coronavirus. As very few guidelines are available for care of cancer patients during COVID times, institutes have had to make their own strategies, based on their own expertise keeping in mind local directives and their effect on available resources and routine processes to offer best possible care. In this article, we have discussed in-house protocols for modification and prioritization of radical and palliative multimodality treatment of cancer patients along with our infection control measures in accordance with national and local guidelines during COVID emergency to stay safe and health. Also, the current study aims to modify cancer treatment and care during the COVID-19 pandemic adhering and fulfilling all protective measures.
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The vascular endothelium is a protective barrier between the bloodstream and the vasculature that may be disrupted by different factors such as the presence of diseased states. Diseases like diabetes and obesity pose a great risk toward endothelial cell inflammation and oxidative stress, leading to endothelial cell dysfunction and thereby cardiovascular complications such as atherosclerosis. Sirtuins are NAD+-dependent histone deacetylases that are implicated in the pathophysiology of cardiovascular diseases, and they have been identified to be important regulators of endothelial cell function. A handful of recent studies suggest that disbalance in the regulation of endothelial sirtuins, mainly sirtuin 1 (SIRT1), contributes to endothelial cell dysfunction. Herein, we summarize how SIRT1 and other sirtuins may contribute to endothelial cell function and how presence of diseased conditions may alter their expressions to cause endothelial dysfunction. Moreover, we discuss how the beneficial effects of exercise on the endothelium are dependent on SIRT1. These mainly include regulation of signaling pathways related to endothelial nitric oxide synthase phosphorylation and nitric oxide production, mitochondrial biogenesis and mitochondria-mediated apoptotic pathways, oxidative stress and inflammatory pathways. Sirtuins as modulators of the adverse conditions in the endothelium hold a promising therapeutic potential for health conditions related to endothelial dysfunction and vascular ageing.
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Envelhecimento , Células Endoteliais/patologia , Endotélio Vascular/fisiopatologia , Sirtuínas , Doenças Vasculares , Humanos , Inflamação , Estresse Oxidativo , Transdução de Sinais , Sirtuína 1 , Sirtuínas/fisiologiaAssuntos
Carcinoma Neuroendócrino/patologia , Neoplasias da Vesícula Biliar/patologia , Dor Abdominal/etiologia , Adulto , Carcinoma Neuroendócrino/diagnóstico , Carcinoma Neuroendócrino/tratamento farmacológico , Feminino , Neoplasias da Vesícula Biliar/diagnóstico , Neoplasias da Vesícula Biliar/tratamento farmacológico , Humanos , Cuidados Paliativos , Tomografia Computadorizada por Raios XRESUMO
The vascular endothelium acts as a barrier between the blood flow and the inner lining of the vessel wall, and it functions as a filtering machinery to filter out any unwanted transfer of materials from both sides (i.e. the blood and the surrounding tissues). It is evident that diseases such as diabetes, obesity, and hypertension disturb the normal endothelial functions in humans and lead to endothelial dysfunction, which may further precede to the development of atherosclerosis. Long non-coding RNAs and micro RNAs both are types of non-coding RNAs which, in the recent years, have increasingly been studied in the pathophysiology of many diseases including diabetes, obesity, cardiovascular diseases, neurological diseases, and others. Recent findings have pointed out important aspects on their relevance to endothelial function as well as dysfunction of the system which may arise from presence of diseases such as diabetes and hypertension. Diabetes or hypertension-mediated endothelial dysfunction show characteristics such as reduced nitric oxide synthesis through suppression of endothelial nitric oxide synthase activity in endothelial cells, reduced sensitivity of nitric oxide in smooth muscle cells, and inflammation - all of which have been either shown to be directly caused by gene regulatory mechanisms of non-coding RNAs or shown to be having a correlation with them. In this review, we aim to discuss such findings on the role of these non-coding RNAs in diabetes or hypertension-associated endothelial dysfunction and the related mechanisms that may pave the way for alleviating endothelial dysfunction and its related complications such as atherosclerosis.
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Diabetes Mellitus/genética , Hipertensão/genética , MicroRNAs/fisiologia , RNA Longo não Codificante/fisiologia , Indutores da Angiogênese , Animais , Aterosclerose/fisiopatologia , Doenças Cardiovasculares/fisiopatologia , Diabetes Mellitus/fisiopatologia , Células Endoteliais/fisiologia , Endotélio Vascular/fisiopatologia , Humanos , Hiperglicemia/genética , Hiperglicemia/fisiopatologia , Hipertensão/fisiopatologia , Inflamação/fisiopatologia , MicroRNAs/genética , Óxido Nítrico , Óxido Nítrico Sintase Tipo III , RNA Longo não Codificante/genéticaRESUMO
CONTEXT: - Telepathology is the practice of pathology at a distance, transmitting images using telecommunication methods for second opinion and/or diagnostic assistance, or for educational purposes. It may be the only means of consultation for some pathologists. OBJECTIVE: - To retrospectively review and evaluate a subset of telepathology consultations from June 1996 to March 1997, and to determine the concordance between the telepathology diagnosis of the contributor and pathologists at the Armed Forces Institute of Pathology (AFIP), Washington, District of Columbia, as well as the concordance between the telepathology diagnosis and the glass slide diagnosis, when available. DESIGN: - Photocopies of de-identified telepathology reports from the AFIP during a 15-month period between June 1996 and March 1997 were reviewed. Contributor versus telepathology diagnosis was graded as 1 (complete agreement), 2 (partial agreement), 3 (disagreement; usually a diagnosis of benign versus malignant), and deferred. Data were analyzed using descriptive statistical methods. RESULTS: - Of the 262 cases, 194 (74%) were in complete agreement with the contributor's diagnosis, 34 of 262 (13%) were in minor disagreement, and 21 of 262 (8%) were in major disagreement. Diagnoses were deferred in 5% (13 of 262) of cases. CONCLUSIONS: - Using commercial off-the-shelf technology and despite telecommunication challenges during that time, the AFIP demonstrated that telepathology could be conducted reliably.
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Consulta Remota , Telepatologia , Humanos , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Estudos RetrospectivosRESUMO
BACKGROUND: In the year 2014, Android smartphones accounted for one-third of mobile connections globally but are predicted to increase to two-thirds by 2020. In developing countries, where teleconsultations can benefit health-care providers most, the ratio is even higher. This study compared the use of two Android phones, an 8 megapixel (MP) and a 16 MP phone, for capturing microscopic images. METHOD: The Android phones were used to capture images and videos of a gastrointestinal biopsy teaching set of referred cases from the Armed Forces Institute of Pathology (AFIP). The acquired images and videos were reviewed online by two pathologists for image quality, adequacy for diagnosis, usefulness of video overviews, and confidence in diagnosis, on a 5-point Likert scale. RESULTS: The results show higher means in a 5-point Likert scale for the 8 MP versus the 16 MP phone that were statistically significant in adequacy of images (4.0 vs. 3.75) for rendering diagnosis and for agreement with the reference diagnosis (2.33 vs. 2.07). Although the quality of images was found higher in the 16 MP phone (3.8 vs. 3.65), these were not statistically significant. Adding video images of the entire specimen was found to be useful for evaluating the slides (combined mean, 4.0). CONCLUSION: For telepathology and other image dependent practices in developing countries, Android phones could be a useful tool for capturing images.
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Calcifying fibrous tumor (CFT) is a rare benign mesenchymal lesion known to arise at multiple body sites that may clinically mimic other more aggressive lesions in the gastrointestinal (GI) tract. In this study we describe the clinicopathologic findings of 28 GI tract CFTs. Tumors predominantly arose in middle-aged adults with a slight female predominance. The most commonly involved sites were small bowel and colon, followed by stomach and appendix. Tumors ranged from 0.3 to 9.3 cm (median 1.4 cm), and submucosa was the most commonly involved layer. All tumors were well circumscribed and unencapsulated. Microscopically, tumors were hypocellular and composed of spindle cells with abundant, haphazardly arranged hyalinized collagen. No necrosis and less than one mitosis per 10 HPF were identified in all cases. Calcification was present in most (81%) of the cases. All cases had lymphoplasmacytic inflammatory infiltrates either scattered throughout the lesion with occasional perivascular conglomeration or in the form of lymphoid aggregates. A lymphoplasmacytic cuff was usually present (81%). Immunostains showed variable CD34 immunoreactivity and variable numbers of IgG4-positive plasma cells. The lesional cells were negative for DOG-1, ALK-1, S100, C-kit, Sox10, Melan A, HMB45, desmin, CK7, and CK20, and showed cytoplasmic staining for ß-catenin. Follow-up information was available in 5 cases with no recurrences reported to date (mean follow-up, 3 years). CFT is a rare benign tumor that can occur in part of the GI tract and should be distinguished from other mesenchymal tumors due to its low risk of recurrence.
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Calcinose/patologia , Neoplasias Gastrointestinais/patologia , Neoplasias de Tecido Fibroso/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Biópsia , Calcinose/metabolismo , Calcinose/cirurgia , Diagnóstico Diferencial , Feminino , Neoplasias Gastrointestinais/química , Neoplasias Gastrointestinais/cirurgia , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Neoplasias de Tecido Fibroso/química , Neoplasias de Tecido Fibroso/cirurgia , Valor Preditivo dos Testes , Fatores de Tempo , Resultado do Tratamento , Carga Tumoral , Adulto JovemRESUMO
[This corrects the article DOI: 10.1155/2012/214209.].
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Although significant advances in radiotherapy have increased its effectiveness in many cancer settings, general strategies to widen the therapeutic window between normal tissue toxicity and malignant tumor destruction would still offer great value. CD47 blockade has been found to confer radioprotection to normal tissues while enhancing tumor radiosensitivity. Here, we report that CD47 blockade directly enhances tumor immunosurveillance by CD8(+) T cells. Combining CD47 blockade with irradiation did not affect fibrosarcoma growth in T cell-deficient mice, whereas adoptive transfer of tumor-specific CD8(+) T cells restored combinatorial efficacy. Furthermore, ablation of CD8(+) T cells abolished radiotherapeutic response in immunocompetent syngeneic hosts. CD47 blockade in either target cells or effector cells was sufficient to enhance antigen-dependent CD8(+) CTL-mediated tumor cell killing in vitro. In CD47-deficient syngeneic hosts, engrafted B16 melanomas were 50% more sensitive to irradiation, establishing that CD47 expression in the microenvironment was sufficient to limit tumor radiosensitivity. Mechanistic investigations revealed increased tumor infiltration by cytotoxic CD8(+) T cells in a CD47-deficient microenvironment, with an associated increase in T cell-dependent intratumoral expression of granzyme B. Correspondingly, an inverse correlation between CD8(+) T-cell infiltration and CD47 expression was observed in human melanomas. Our findings establish that blocking CD47 in the context of radiotherapy enhances antitumor immunity by directly stimulating CD8(+) cytotoxic T cells, with the potential to increase curative responses.
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Antígeno CD47/imunologia , Linfócitos T CD8-Positivos/imunologia , Tolerância a Radiação/imunologia , Linfócitos T Citotóxicos/imunologia , Microambiente Tumoral/imunologia , Transferência Adotiva/métodos , Animais , Linhagem Celular Tumoral , Citotoxicidade Imunológica , Fibrossarcoma/imunologia , Granzimas/imunologia , Humanos , Melanoma Experimental/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , Radioterapia/métodosAssuntos
Neoplasias Faciais/patologia , Síndrome de Muir-Torre/patologia , Neoplasias da Bexiga Urinária/patologia , Idoso , Biópsia , Reparo de Erro de Pareamento de DNA/genética , Neoplasias Faciais/genética , Feminino , Mutação em Linhagem Germinativa , Humanos , Instabilidade de Microssatélites , Síndrome de Muir-Torre/genética , Neoplasias da Bexiga Urinária/genéticaRESUMO
CONTEXT: Carcinoids have rarely been described in von Hippel-Lindau (VHL) disease. OBJECTIVE: We describe the first reported case of a patient with VHL who developed a pulmonary carcinoid that subsequently metastasized to a pre-existent cranial hemangioblastoma. RESULTS: Histological and immunohistochemical features of the metastatic lesion were similar to the primary carcinoid. Both lesions demonstrated heterozygous VHL gene deletions with fluorescence in situ hybridization analysis. CONCLUSIONS: This case provides direct molecular genetic evidence of an association between VHL and carcinoids.
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Neoplasias Encefálicas/patologia , Tumor Carcinoide/etiologia , Hemangioblastoma/patologia , Neoplasias Pulmonares/etiologia , Segunda Neoplasia Primária/diagnóstico , Doença de von Hippel-Lindau/complicações , Adulto , Neoplasias Encefálicas/diagnóstico , Tumor Carcinoide/diagnóstico , Tumor Carcinoide/patologia , Hemangioblastoma/diagnóstico , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/patologia , Metástase Linfática , Masculino , Segunda Neoplasia Primária/patologia , Doença de von Hippel-Lindau/diagnósticoRESUMO
More than 2.5 million Americans suffer from burn injuries annually, and burn management is a major public health problem. Treatments have been developed to manage wound injuries employing skin grafts, various dressings and topical and systemic agents. However, these often achieve limited degrees of success. We previously reported that targeting the interaction of thrombospondin-1 with its signaling receptor CD47 or deletion of the genes encoding either of these proteins in mice improves recovery from soft tissue ischemic injuries as well as tissue injuries caused by ionizing radiation. We now demonstrate that the absence of CD47 improves the rate of wound closure for a focal dermal second-degree thermal injury, whereas lack of thrombospondin-1 initially delays wound closure compared to healing in wild type mice. Doppler analysis of the wounded area showed increased blood flow in both CD47 and thrombospondin-1 null mice. Accelerated wound closure in the CD47 null mice was associated with increased fibrosis as demonstrated by a 4-fold increase in collagen fraction. Wound tissue of CD47 null mice showed increased thrombospondin-1 mRNA and protein expression and TGF-ß1 mRNA levels. Activation of latent TGF-ß1 was increased in thermally injured CD47-null tissue as assessed by phosphorylation of the TGF-ß1 receptor-regulated transcription factors SMAD-2 and -3. Overall these results indicate that targeting CD47 may improve the speed of healing thermal injuries, but some level of CD47 expression may be required to limit the long term TGF-ß1-dependent fibrosis of these wounds.
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Queimaduras/fisiopatologia , Antígeno CD47/metabolismo , Transdução de Sinais/fisiologia , Pele/fisiopatologia , Trombospondina 1/metabolismo , Cicatrização/fisiologia , Animais , Colágeno/metabolismo , Imuno-Histoquímica , Fluxometria por Laser-Doppler , Camundongos , Camundongos Endogâmicos C57BL , Morfolinos/genética , Fosforilação , Reação em Cadeia da Polimerase em Tempo Real , Proteína Smad2/metabolismo , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta1/metabolismoRESUMO
von Willebrand disease (VWD) is the most common inherited human bleeding disorder and is caused by quantitative or qualitative defects in von Willebrand factor (VWF). VWF is a secreted glycoprotein that circulates as large multimers. While reduced VWF is associated with bleeding, elevations in overall level or multimer size are implicated in thrombosis. The zebrafish is a powerful genetic model in which the hemostatic system is well conserved with mammals. The ability of this organism to generate thousands of offspring and its optical transparency make it unique and complementary to mammalian models of hemostasis. Previously, partial clones of zebrafish vwf have been identified, and some functional conservation has been demonstrated. In this paper we clone the complete zebrafish vwf cDNA and show that there is conservation of domain structure. Recombinant zebrafish Vwf forms large multimers and pseudo-Weibel-Palade bodies (WPBs) in cell culture. Larval expression is in the pharyngeal arches, yolk sac, and intestinal epithelium. These results provide a foundation for continued study of zebrafish Vwf that may further our understanding of the mechanisms of VWD.
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CD36 modulates platelet function via binding to oxidized LDL (oxLDL), cell-derived microparticles, and thrombospondin-1. We hypothesized that the level of platelet CD36 expression may be associated with inheritance of specific genetic polymorphisms and that this would determine platelet reactivity to oxLDL. Analysis of more than 500 subjects revealed that CD36 expression levels were consistent in individual donors over time but varied widely among donors (200-14,000 molecules per platelet). Platelet aggregometry and flow cytometry in a subset of subjects with various CD36 expression levels revealed a high level of correlation (r² = 0.87) between platelet activation responses to oxLDL and level of CD36 expression. A genome-wide association study of 374 white subjects from the Cleveland Clinic ASCLOGEN study showed strong associations of single nucleotide polymorphisms in CD36 with platelet surface CD36 expression. Most of these findings were replicated in a smaller subset of 25 black subjects. An innovative gene-based genome-wide scan provided further evidence that single nucleotide polymorphisms in CD36 were strongly associated with CD36 expression. These studies show that CD36 expression on platelets varies widely, correlates with functional responses to oxLDL, and is associated with inheritance of specific CD36 genetic polymorphisms, and suggest that inheritance of specific CD36 polymorphisms could affect thrombotic risk.