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1.
Int J Mol Sci ; 24(19)2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37834170

RESUMO

Tumor necrosis factor (TNF) binding to endothelial TNF receptor-I (TNFR-I) facilitates monocyte recruitment and chronic inflammation, leading to the development of atherosclerosis. In vitro data show a heightened inflammatory response and atherogenic potential in endothelial cells (ECs) from African American (AA) donors. High laminar shear stress (HSS) can mitigate some aspects of racial differences in endothelial function at the cellular level. We examined possible racial differences in TNF-induced monocyte adhesion and TNFR1 signaling complex expression/activity, along with the effects of HSS. Tohoku Hospital Pediatrics-1 (THP-1) monocytes were used in a co-culture system with human umbilical vein ECs (HUVECs) from Caucasian American (CA) and AA donors to examine racial differences in monocyte adhesion. An in vitro exercise mimetic model was applied to investigate the potential modulatory effect of HSS. THP-1 adherence to ECs and TNF-induced nuclear factor kappa B (NF-κB) DNA binding were elevated in AA ECs compared to CA ECs, but not significantly. We report no significant racial differences in the expression of the TNFR-I signaling complex. Application of HSS significantly increased the expression and shedding of TNFR-I and the expression of TRAF3, and decreased the expression of TRAF5 in both groups. Our data does not support TNF-induced NF-κB activation as a potential mediator of racial disparity in this model. Other pathways and associated factors activated by the TNFR1 signaling complex are recommended targets for future research.


Assuntos
NF-kappa B , Receptores Tipo I de Fatores de Necrose Tumoral , Criança , Humanos , Adesão Celular , Células Cultivadas , Células Endoteliais da Veia Umbilical Humana/metabolismo , Monócitos/metabolismo , NF-kappa B/metabolismo , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Transdução de Sinais/fisiologia , Fator de Necrose Tumoral alfa/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Fatores Raciais , Estresse Mecânico
2.
Lancet Oncol ; 24(5): 443-456, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37142371

RESUMO

BACKGROUND: Abiraterone acetate plus prednisolone (herein referred to as abiraterone) or enzalutamide added at the start of androgen deprivation therapy improves outcomes for patients with metastatic prostate cancer. Here, we aimed to evaluate long-term outcomes and test whether combining enzalutamide with abiraterone and androgen deprivation therapy improves survival. METHODS: We analysed two open-label, randomised, controlled, phase 3 trials of the STAMPEDE platform protocol, with no overlapping controls, conducted at 117 sites in the UK and Switzerland. Eligible patients (no age restriction) had metastatic, histologically-confirmed prostate adenocarcinoma; a WHO performance status of 0-2; and adequate haematological, renal, and liver function. Patients were randomly assigned (1:1) using a computerised algorithm and a minimisation technique to either standard of care (androgen deprivation therapy; docetaxel 75 mg/m2 intravenously for six cycles with prednisolone 10 mg orally once per day allowed from Dec 17, 2015) or standard of care plus abiraterone acetate 1000 mg and prednisolone 5 mg (in the abiraterone trial) orally or abiraterone acetate and prednisolone plus enzalutamide 160 mg orally once a day (in the abiraterone and enzalutamide trial). Patients were stratified by centre, age, WHO performance status, type of androgen deprivation therapy, use of aspirin or non-steroidal anti-inflammatory drugs, pelvic nodal status, planned radiotherapy, and planned docetaxel use. The primary outcome was overall survival assessed in the intention-to-treat population. Safety was assessed in all patients who started treatment. A fixed-effects meta-analysis of individual patient data was used to compare differences in survival between the two trials. STAMPEDE is registered with ClinicalTrials.gov (NCT00268476) and ISRCTN (ISRCTN78818544). FINDINGS: Between Nov 15, 2011, and Jan 17, 2014, 1003 patients were randomly assigned to standard of care (n=502) or standard of care plus abiraterone (n=501) in the abiraterone trial. Between July 29, 2014, and March 31, 2016, 916 patients were randomly assigned to standard of care (n=454) or standard of care plus abiraterone and enzalutamide (n=462) in the abiraterone and enzalutamide trial. Median follow-up was 96 months (IQR 86-107) in the abiraterone trial and 72 months (61-74) in the abiraterone and enzalutamide trial. In the abiraterone trial, median overall survival was 76·6 months (95% CI 67·8-86·9) in the abiraterone group versus 45·7 months (41·6-52·0) in the standard of care group (hazard ratio [HR] 0·62 [95% CI 0·53-0·73]; p<0·0001). In the abiraterone and enzalutamide trial, median overall survival was 73·1 months (61·9-81·3) in the abiraterone and enzalutamide group versus 51·8 months (45·3-59·0) in the standard of care group (HR 0·65 [0·55-0·77]; p<0·0001). We found no difference in the treatment effect between these two trials (interaction HR 1·05 [0·83-1·32]; pinteraction=0·71) or between-trial heterogeneity (I2 p=0·70). In the first 5 years of treatment, grade 3-5 toxic effects were higher when abiraterone was added to standard of care (271 [54%] of 498 vs 192 [38%] of 502 with standard of care) and the highest toxic effects were seen when abiraterone and enzalutamide were added to standard of care (302 [68%] of 445 vs 204 [45%] of 454 with standard of care). Cardiac causes were the most common cause of death due to adverse events (five [1%] with standard of care plus abiraterone and enzalutamide [two attributed to treatment] and one (<1%) with standard of care in the abiraterone trial). INTERPRETATION: Enzalutamide and abiraterone should not be combined for patients with prostate cancer starting long-term androgen deprivation therapy. Clinically important improvements in survival from addition of abiraterone to androgen deprivation therapy are maintained for longer than 7 years. FUNDING: Cancer Research UK, UK Medical Research Council, Swiss Group for Clinical Cancer Research, Janssen, and Astellas.


Assuntos
Neoplasias de Próstata Resistentes à Castração , Neoplasias da Próstata , Masculino , Humanos , Acetato de Abiraterona , Neoplasias da Próstata/patologia , Antagonistas de Androgênios , Androgênios , Prednisolona , Docetaxel/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/patologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Ensaios Clínicos Fase III como Assunto , Metanálise como Assunto
3.
Sci Rep ; 12(1): 6660, 2022 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-35459777

RESUMO

Advances in multiplex immunofluorescence (mIF) and digital image analysis has enabled simultaneous assessment of protein defects in electron transport chain components. However, current manual methodology is time consuming and labour intensive. Therefore, we developed an automated high-throughput mIF workflow for quantitative single-cell level assessment of formalin fixed paraffin embedded tissue (FFPE), leveraging tyramide signal amplification on a Ventana Ultra platform coupled with automated multispectral imaging on a Vectra 3 platform. Utilising this protocol, we assessed the mitochondrial oxidative phosphorylation (OXPHOS) protein alterations in a cohort of benign and malignant prostate samples. Mitochondrial OXPHOS plays a critical role in cell metabolism, and OXPHOS perturbation is implicated in carcinogenesis. Marked inter-patient, intra-patient and spatial cellular heterogeneity in OXPHOS protein abundance was observed. We noted frequent Complex IV loss in benign prostate tissue and Complex I loss in age matched prostate cancer tissues. Malignant regions within prostate cancer samples more frequently contained cells with low Complex I & IV and high mitochondrial mass in comparison to benign-adjacent regions. This methodology can now be applied more widely to study the frequency and distribution of OXPHOS alterations in formalin-fixed tissues, and their impact on long-term clinical outcomes.


Assuntos
Imunofluorescência , Próstata , Neoplasias da Próstata , Complexo IV da Cadeia de Transporte de Elétrons , Imunofluorescência/métodos , Formaldeído , Humanos , Masculino , Fosforilação Oxidativa , Inclusão em Parafina , Próstata/diagnóstico por imagem , Neoplasias da Próstata/diagnóstico por imagem , Fixação de Tecidos
4.
Ann Gastroenterol ; 34(3): 310-315, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33948054

RESUMO

Diabetes mellitus is a risk factor for poor bowel preparation in patients who undergo colonoscopy, because of their decreased intestinal transit and slow gastric emptying. This might lead to neoplastic or preneoplastic lesions being missed, longer procedural time, a higher risk of procedure-related adverse events, significant cost burden, patient dissatisfaction, and the need for a repeat colonoscopy. Multiple strategies have been suggested to improve bowel preparation in these patients. Proposed pharmacologic strategies include adding magnesium citrate, bisacodyl, lubiprostone or pyridostigmine. Non-pharmacologic strategies include preferential procedure scheduling or using a diabetes-specific preparation protocol. In this article, we present a comprehensive review of the literature and provide specific recommendations to general practitioners and gastroenterologists for improving bowel preparation in patients with diabetes.

5.
Front Physiol ; 12: 773995, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34975527

RESUMO

We sought to determine if manipulating resistance training (RT) variables differentially altered the expression of select sarcoplasmic and myofibril proteins as well as myofibrillar spacing in myofibers. Resistance-trained men (n = 20; 26 ± 3 years old) trained for 8 weeks where a randomized leg performed either a standard (CON) or variable RT protocol (VAR: manipulation of load, volume, muscle action, and rest intervals at each RT session). A pre-training (PRE) vastus lateralis biopsy was obtained from a randomized single leg, and biopsies were obtained from both legs 96 h following the last training bout. The sarcoplasmic protein pool was assayed for proteins involved in energy metabolism, and the myofibril protein pool was assayed for relative myosin heavy chain (MHC) and actin protein abundances. Sections were also histologically analyzed to obtain myofibril spacing characteristics. VAR resulted in ~12% greater volume load (VL) compared to CON (p < 0.001). The mean fiber cross-sectional area increased following both RT protocols [CON: 14.6% (775.5 µm2), p = 0.006; VAR: 13.9% (743.2 µm2), p = 0.01 vs. PRE for both], but without significant differences between protocols (p = 0.79). Neither RT protocol affected a majority of assayed proteins related to energy metabolism, but both training protocols increased hexokinase 2 protein levels and decreased a mitochondrial beta-oxidation marker (VLCAD protein; p < 0.05). Citrate synthase activity levels increased with CON RT (p < 0.05), but not VAR RT. The relative abundance of MHC (summed isoforms) decreased with both training protocols (p < 0.05). However, the relative abundance of actin protein (summed isoforms) decreased with VAR only (13.5 and 9.0%, respectively; p < 0.05). A decrease in percent area occupied by myofibrils was observed from PRE to VAR (-4.87%; p = 0.048), but not for the CON (4.53%; p = 0.979). In contrast, there was an increase in percent area occupied by non-contractile space from PRE to VAR (10.14%; p = 0.048), but not PRE to CON (0.72%; p = 0.979). In conclusion, while both RT protocols increased muscle fiber hypertrophy, a higher volume-load where RT variables were frequently manipulated increased non-contractile spacing in resistance-trained individuals.

6.
Otolaryngol Head Neck Surg ; 162(1_suppl): S1-S38, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31910111

RESUMO

OBJECTIVE: Nosebleed, also known as epistaxis, is a common problem that occurs at some point in at least 60% of people in the United States. While the majority of nosebleeds are limited in severity and duration, about 6% of people who experience nosebleeds will seek medical attention. For the purposes of this guideline, we define the target patient with a nosebleed as a patient with bleeding from the nostril, nasal cavity, or nasopharynx that is sufficient to warrant medical advice or care. This includes bleeding that is severe, persistent, and/or recurrent, as well as bleeding that impacts a patient's quality of life. Interventions for nosebleeds range from self-treatment and home remedies to more intensive procedural interventions in medical offices, emergency departments, hospitals, and operating rooms. Epistaxis has been estimated to account for 0.5% of all emergency department visits and up to one-third of all otolaryngology-related emergency department encounters. Inpatient hospitalization for aggressive treatment of severe nosebleeds has been reported in 0.2% of patients with nosebleeds. PURPOSE: The primary purpose of this multidisciplinary guideline is to identify quality improvement opportunities in the management of nosebleeds and to create clear and actionable recommendations to implement these opportunities in clinical practice. Specific goals of this guideline are to promote best practices, reduce unjustified variations in care of patients with nosebleeds, improve health outcomes, and minimize the potential harms of nosebleeds or interventions to treat nosebleeds. The target patient for the guideline is any individual aged ≥3 years with a nosebleed or history of nosebleed who needs medical treatment or seeks medical advice. The target audience of this guideline is clinicians who evaluate and treat patients with nosebleed. This includes primary care providers such as family medicine physicians, internists, pediatricians, physician assistants, and nurse practitioners. It also includes specialists such as emergency medicine providers, otolaryngologists, interventional radiologists/neuroradiologists and neurointerventionalists, hematologists, and cardiologists. The setting for this guideline includes any site of evaluation and treatment for a patient with nosebleed, including ambulatory medical sites, the emergency department, the inpatient hospital, and even remote outpatient encounters with phone calls and telemedicine. Outcomes to be considered for patients with nosebleed include control of acute bleeding, prevention of recurrent episodes of nasal bleeding, complications of treatment modalities, and accuracy of diagnostic measures. This guideline addresses the diagnosis, treatment, and prevention of nosebleed. It focuses on nosebleeds that commonly present to clinicians via phone calls, office visits, and emergency room encounters. This guideline discusses first-line treatments such as nasal compression, application of vasoconstrictors, nasal packing, and nasal cautery. It also addresses more complex epistaxis management, which includes the use of endoscopic arterial ligation and interventional radiology procedures. Management options for 2 special groups of patients-patients with hereditary hemorrhagic telangiectasia syndrome and patients taking medications that inhibit coagulation and/or platelet function-are included in this guideline. This guideline is intended to focus on evidence-based quality improvement opportunities judged most important by the guideline development group. It is not intended to be a comprehensive, general guide for managing patients with nosebleed. In this context, the purpose is to define useful actions for clinicians, generalists, and specialists from a variety of disciplines to improve quality of care. Conversely, the statements in this guideline are not intended to limit or restrict care provided by clinicians based on their experience and assessment of individual patients. ACTION STATEMENTS: The guideline development group made recommendations for the following key action statements: (1) At the time of initial contact, the clinician should distinguish the nosebleed patient who requires prompt management from the patient who does not. (2) The clinician should treat active bleeding for patients in need of prompt management with firm sustained compression to the lower third of the nose, with or without the assistance of the patient or caregiver, for 5 minutes or longer. (3a) For patients in whom bleeding precludes identification of a bleeding site despite nasal compression, the clinician should treat ongoing active bleeding with nasal packing. (3b) The clinician should use resorbable packing for patients with a suspected bleeding disorder or for patients who are using anticoagulation or antiplatelet medications. (4) The clinician should educate the patient who undergoes nasal packing about the type of packing placed, timing of and plan for removal of packing (if not resorbable), postprocedure care, and any signs or symptoms that would warrant prompt reassessment. (5) The clinician should document factors that increase the frequency or severity of bleeding for any patient with a nosebleed, including personal or family history of bleeding disorders, use of anticoagulant or antiplatelet medications, or intranasal drug use. (6) The clinician should perform anterior rhinoscopy to identify a source of bleeding after removal of any blood clot (if present) for patients with nosebleeds. (7a) The clinician should perform, or should refer to a clinician who can perform, nasal endoscopy to identify the site of bleeding and guide further management in patients with recurrent nasal bleeding, despite prior treatment with packing or cautery, or with recurrent unilateral nasal bleeding. (8) The clinician should treat patients with an identified site of bleeding with an appropriate intervention, which may include one or more of the following: topical vasoconstrictors, nasal cautery, and moisturizing or lubricating agents. (9) When nasal cautery is chosen for treatment, the clinician should anesthetize the bleeding site and restrict application of cautery only to the active or suspected site(s) of bleeding. (10) The clinician should evaluate, or refer to a clinician who can evaluate, candidacy for surgical arterial ligation or endovascular embolization for patients with persistent or recurrent bleeding not controlled by packing or nasal cauterization. (11) In the absence of life-threatening bleeding, the clinician should initiate first-line treatments prior to transfusion, reversal of anticoagulation, or withdrawal of anticoagulation/antiplatelet medications for patients using these medications. (12) The clinician should assess, or refer to a specialist who can assess, the presence of nasal telangiectasias and/or oral mucosal telangiectasias in patients who have a history of recurrent bilateral nosebleeds or a family history of recurrent nosebleeds to diagnose hereditary hemorrhagic telangiectasia syndrome. (13) The clinician should educate patients with nosebleeds and their caregivers about preventive measures for nosebleeds, home treatment for nosebleeds, and indications to seek additional medical care. (14) The clinician or designee should document the outcome of intervention within 30 days or document transition of care in patients who had a nosebleed treated with nonresorbable packing, surgery, or arterial ligation/embolization. The policy level for the following recommendation, about examination of the nasal cavity and nasopharynx using nasal endoscopy, was an option: (7b) The clinician may perform, or may refer to a clinician who can perform, nasal endoscopy to examine the nasal cavity and nasopharynx in patients with epistaxis that is difficult to control or when there is concern for unrecognized pathology contributing to epistaxis.


Assuntos
Cauterização , Endoscopia/métodos , Epistaxe/terapia , Ligadura , Melhoria de Qualidade , Vasoconstritores/uso terapêutico , Epistaxe/diagnóstico , Epistaxe/prevenção & controle , Hemostáticos/uso terapêutico , Humanos , Procedimentos Cirúrgicos Nasais/métodos , Gravidade do Paciente , Educação de Pacientes como Assunto/métodos , Fatores de Risco , Tampões Cirúrgicos , Telangiectasia Hemorrágica Hereditária/diagnóstico
7.
Otolaryngol Head Neck Surg ; 162(1): 8-25, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31910122

RESUMO

OBJECTIVE: Nosebleed, also known as epistaxis, is a common problem that occurs at some point in at least 60% of people in the United States. While the great majority of nosebleeds are limited in severity and duration, about 6% of people who experience nosebleeds will seek medical attention. For the purposes of this guideline, we define the target patient with a nosebleed as a patient with bleeding from the nostril, nasal cavity, or nasopharynx that is sufficient to warrant medical advice or care. This includes bleeding that is severe, persistent, and/or recurrent, as well as bleeding that impacts a patient's quality of life. Interventions for nosebleeds range from self-treatment and home remedies to more intensive procedural interventions in medical offices, emergency departments, hospitals, and operating rooms. Epistaxis has been estimated to account for 0.5% of all emergency department visits and up to one-third of all otolaryngology-related emergency department encounters. Inpatient hospitalization for aggressive treatment of severe nosebleeds has been reported in 0.2% of patients with nosebleeds. PURPOSE: The primary purpose of this multidisciplinary guideline is to identify quality improvement opportunities in the management of nosebleeds and to create clear and actionable recommendations to implement these opportunities in clinical practice. Specific goals of this guideline are to promote best practices, reduce unjustified variations in care of patients with nosebleeds, improve health outcomes, and minimize the potential harms of nosebleeds or interventions to treat nosebleeds. The target patient for the guideline is any individual aged ≥3 years with a nosebleed or history of nosebleed who needs medical treatment or seeks medical advice. The target audience of this guideline is clinicians who evaluate and treat patients with nosebleed. This includes primary care providers such as family medicine physicians, internists, pediatricians, physician assistants, and nurse practitioners. It also includes specialists such as emergency medicine providers, otolaryngologists, interventional radiologists/neuroradiologists and neurointerventionalists, hematologists, and cardiologists. The setting for this guideline includes any site of evaluation and treatment for a patient with nosebleed, including ambulatory medical sites, the emergency department, the inpatient hospital, and even remote outpatient encounters with phone calls and telemedicine. Outcomes to be considered for patients with nosebleed include control of acute bleeding, prevention of recurrent episodes of nasal bleeding, complications of treatment modalities, and accuracy of diagnostic measures. This guideline addresses the diagnosis, treatment, and prevention of nosebleed. It will focus on nosebleeds that commonly present to clinicians with phone calls, office visits, and emergency room encounters. This guideline discusses first-line treatments such as nasal compression, application of vasoconstrictors, nasal packing, and nasal cautery. It also addresses more complex epistaxis management, which includes the use of endoscopic arterial ligation and interventional radiology procedures. Management options for 2 special groups of patients, patients with hemorrhagic telangiectasia syndrome (HHT) and patients taking medications that inhibit coagulation and/or platelet function, are included in this guideline. This guideline is intended to focus on evidence-based quality improvement opportunities judged most important by the working group. It is not intended to be a comprehensive, general guide for managing patients with nosebleed. In this context, the purpose is to define useful actions for clinicians, generalists, and specialists from a variety of disciplines to improve quality of care. Conversely, the statements in this guideline are not intended to limit or restrict care provided by clinicians based upon their experience and assessment of individual patients. ACTION STATEMENTS: The guideline development group made recommendations for the following key action statements: (1) At the time of initial contact, the clinician should distinguish the nosebleed patient who requires prompt management from the patient who does not. (2) The clinician should treat active bleeding for patients in need of prompt management with firm sustained compression to the lower third of the nose, with or without the assistance of the patient or caregiver, for 5 minutes or longer. (3a) For patients in whom bleeding precludes identification of a bleeding site despite nasal compression, the clinician should treat ongoing active bleeding with nasal packing. (3b) The clinician should use resorbable packing for patients with a suspected bleeding disorder or for patients who are using anticoagulation or antiplatelet medications. (4) The clinician should educate the patient who undergoes nasal packing about the type of packing placed, timing of and plan for removal of packing (if not resorbable), postprocedure care, and any signs or symptoms that would warrant prompt reassessment. (5) The clinician should document factors that increase the frequency or severity of bleeding for any patient with a nosebleed, including personal or family history of bleeding disorders, use of anticoagulant or antiplatelet medications, or intranasal drug use. (6) The clinician should perform anterior rhinoscopy to identify a source of bleeding after removal of any blood clot (if present) for patients with nosebleeds. (7a) The clinician should perform, or should refer to a clinician who can perform, nasal endoscopy to identify the site of bleeding and guide further management in patients with recurrent nasal bleeding, despite prior treatment with packing or cautery, or with recurrent unilateral nasal bleeding. (8) The clinician should treat patients with an identified site of bleeding with an appropriate intervention, which may include 1 or more of the following: topical vasoconstrictors, nasal cautery, and moisturizing or lubricating agents. (9) When nasal cautery is chosen for treatment, the clinician should anesthetize the bleeding site and restrict application of cautery only to the active or suspected site(s) of bleeding. (10) The clinician should evaluate, or refer to a clinician who can evaluate, candidacy for surgical arterial ligation or endovascular embolization for patients with persistent or recurrent bleeding not controlled by packing or nasal cauterization. (11) In the absence of life-threatening bleeding, the clinician should initiate first-line treatments prior to transfusion, reversal of anticoagulation, or withdrawal of anticoagulation/antiplatelet medications for patients using these medications. (12) The clinician should assess, or refer to a specialist who can assess, the presence of nasal telangiectasias and/or oral mucosal telangiectasias in patients who have a history of recurrent bilateral nosebleeds or a family history of recurrent nosebleeds to diagnose hereditary hemorrhagic telangiectasia syndrome (HHT). (13) The clinician should educate patients with nosebleeds and their caregivers about preventive measures for nosebleeds, home treatment for nosebleeds, and indications to seek additional medical care. (14) The clinician or designee should document the outcome of intervention within 30 days or document transition of care in patients who had a nosebleed treated with nonresorbable packing, surgery, or arterial ligation/embolization. The policy level for the following recommendation about examination of the nasal cavity and nasopharynx using nasal endoscopy was an option: (7b) The clinician may perform, or may refer to a clinician who can perform, nasal endoscopy to examine the nasal cavity and nasopharynx in patients with epistaxis that is difficult to control or when there is concern for unrecognized pathology contributing to epistaxis.


Assuntos
Epistaxe/epidemiologia , Epistaxe/terapia , Procedimentos Cirúrgicos Nasais/métodos , Guias de Prática Clínica como Assunto , Melhoria de Qualidade , Tratamento Conservador/métodos , Epistaxe/diagnóstico , Medicina Baseada em Evidências , Fidelidade a Diretrizes , Humanos , Incidência , Ligadura/métodos , Qualidade de Vida , Recidiva , Medição de Risco , Índice de Gravidade de Doença , Resultado do Tratamento
8.
Acad Med ; 95(2): 283-292, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31335810

RESUMO

PURPOSE: The Next Accreditation System requires training programs to demonstrate competence among trainees. Within gastroenterology (GI), there are limited data describing learning curves and structured assessment of competence in esophagogastroduodenoscopy (EGD) and colonoscopy. In this study, the authors aimed to demonstrate the feasibility of a centralized feedback system to assess endoscopy learning curves among GI trainees in EGD and colonoscopy. METHOD: During academic year 2016-2017, the authors performed a prospective multicenter cohort study, inviting participants from multiple GI training programs. Trainee technical and cognitive skills were assessed using a validated competence assessment tool. An integrated, comprehensive data collection and reporting system was created to apply cumulative sum analysis to generate learning curves that were shared with program directors and trainees on a quarterly basis. RESULTS: Out of 183 fellowships invited, 129 trainees from 12 GI fellowships participated, with an overall trainee participation rate of 72.1% (93/129); the highest participation level was among first-year trainees (90.9%; 80/88), and the lowest was among third-year trainees (51.2%; 27/53). In all, 1,385 EGDs and 1,293 colonoscopies were assessed. On aggregate learning curve analysis, third-year trainees achieved competence in overall technical and cognitive skills, while first- and second-year trainees demonstrated the need for ongoing supervision and training in the majority of technical and cognitive skills. CONCLUSIONS: This study demonstrated the feasibility of using a centralized feedback system for the evaluation and documentation of trainee performance in EGD and colonoscopy. Furthermore, third-year trainees achieved competence in both endoscopic procedures, validating the effectiveness of current training programs.


Assuntos
Colonoscopia/educação , Endoscopia do Sistema Digestório/educação , Gastroenterologia/educação , Acreditação , Competência Clínica , Estudos de Viabilidade , Feminino , Humanos , Curva de Aprendizado , Masculino , Avaliação de Programas e Projetos de Saúde , Estudos Prospectivos
9.
J Appl Physiol (1985) ; 127(4): 895-904, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31369326

RESUMO

The long interspersed nuclear element-1 (L1) is a retrotransposon that constitutes 17% of the human genome and is associated with various diseases and aging. Estimates suggest that ~100 L1 copies are capable of copying and pasting into other regions of the genome. Herein, we examined if skeletal muscle L1 markers are affected by aging or an acute bout of cycling exercise in humans. Apparently healthy younger (23 ± 3 y, n = 15) and older participants (58 ± 8 y, n = 15) donated a vastus lateralis biopsy before 1 h of cycling exercise (PRE) at ~70% of heart rate reserve. Second (2 h) and third (8 h) postexercise muscle biopsies were also obtained. L1 DNA and mRNA expression were quantified using three primer sets [5' untranslated region (UTR), L1.3, and ORF1]. 5'UTR and L1.3 DNA methylation as well as ORF1 protein expression were also quantified. PRE 5'UTR, ORF1, or L1.3 DNA were not different between age groups (P > 0.05). ORF1 mRNA was greater in older versus younger participants (P = 0.014), and cycling lowered this marker at 2 h versus PRE (P = 0.027). 5'UTR and L1.3 DNA methylation were higher in younger versus older participants (P < 0.05). Accelerometry data collected during a 2-wk period before the exercise bout indicated higher moderate-to-vigorous physical activity (MVPA) levels per day was associated with lower PRE ORF1 mRNA in all participants (r = -0.398, P = 0.032). In summary, skeletal muscle ORF1 mRNA is higher in older apparently healthy humans, which may be related to lower DNA methylation patterns. ORF1 mRNA is also reduced with endurance exercise and is negatively associated with higher daily MVPA levels.NEW & NOTEWORTHY The long interspersed nuclear element-1 (L1) gene is highly abundant in the genome and encodes for an autonomous retrotransposon, which is capable of copying and pasting itself into other portions of the genome. This is the first study in humans to demonstrate that certain aspects of skeletal muscle L1 activity are altered with aging. Additionally, this is the first study in humans to demonstrate that L1 ORF1 mRNA levels decrease after a bout of endurance exercise, regardless of age.


Assuntos
Desoxirribonuclease I/metabolismo , Exercício Físico/fisiologia , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiologia , Resistência Física/fisiologia , RNA Mensageiro/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/metabolismo , Envelhecimento/fisiologia , Terapia por Exercício/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Quadríceps/metabolismo , Músculo Quadríceps/fisiologia , Adulto Jovem
10.
Int J Radiat Oncol Biol Phys ; 104(4): 809-818, 2019 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-30885775

RESUMO

PURPOSE: Organ-confined muscle-invasive bladder cancer is treated with cystectomy or bladder preservation techniques, including radiation therapy. There are currently no biomarkers to inform management decisions and aid patient choice. Previously we showed high levels of MRE11 protein, assessed by immunohistochemistry (IHC), predicted outcome after radiation therapy, but not cystectomy. Therefore, we sought to develop the MRE11 IHC assay for clinical use and define its relationship to clinical outcome in samples from 2 major clinical trials. METHODS AND MATERIALS: Samples from the BCON and BC2001 randomized controlled trials and a cystectomy cohort were stained using automated IHC methods and scored for MRE11 in 3 centers in the United Kingdom. RESULTS: Despite step-wise creation of scoring cards and standard operating procedures for staining and interpretation, there was poor intercenter scoring agreement (kappa, 0.32; 95% confidence interval, 0.17-0.47). No significant associations between MRE11 scores and cause-specific survival were identified in BCON (n = 132) and BC2001 (n = 221) samples. Reoptimized staining improved agreement between scores from BCON tissue microarrays (n = 116), but MRE11 expression was not prognostic for cause-specific survival. CONCLUSIONS: Manual IHC scoring of MRE11 was not validated as a reproducible biomarker of radiation-based bladder preservation success. There is a need for automated quantitative methods or a reassessment of how DNA-damage response relates to clinical outcomes.


Assuntos
Biomarcadores Tumorais/análise , Proteína Homóloga a MRE11/análise , Neoplasias da Bexiga Urinária/química , Neoplasias da Bexiga Urinária/radioterapia , Idoso , Idoso de 80 Anos ou mais , Cistectomia , Feminino , Humanos , Imuno-Histoquímica/métodos , Imuno-Histoquímica/normas , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Análise de Sobrevida , Resultado do Tratamento , Reino Unido , Neoplasias da Bexiga Urinária/mortalidade , Neoplasias da Bexiga Urinária/patologia
11.
Med Sci Sports Exerc ; 50(10): 2033-2039, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29771821

RESUMO

INTRODUCTION: Optimal vascular function is a hallmark of cardiovascular health. Specifically, the balance of vasoconstricting and vasodilating substances is recognized as a marker of vascular health. One of the greatest challenges to vascular health and vasodilatory balance is tumor necrosis factor alpha (TNFα)-mediated inflammation. Uncovering effective strategies that maintain a vascular environment that is more vasodilatory and antithrombotic in the face of an inflammatory challenge is favorable. PURPOSE: To test the ability of various antithrombotic and provasodilatory treatments, as well as combinations thereof, to prevent unfavorable changes in markers of endothelial dysfunction in human umbilical vein endothelial cells when presented with an inflammatory challenge. METHODS: Human umbilical vein endothelial cells were pretreated with exercise-like levels of laminar shear stress (LSS), aspirin, celecoxib, and their combination before a TNFα challenge. Western blot analysis as well as colorimetric assays were used to determine levels of endothelial nitric oxide synthase (eNOS) and prostacyclin (6-keto PGF1α)/thromboxane (TXB2) metabolite ratio, respectively. RESULTS: Neither aspirin nor celecoxib were effective in preventing TNFα-induced reduction in eNOS. Further, aspirin was unable to maintain baseline levels of prostacyclin/thromboxane ratio in the face of the inflammatory challenge. Laminar shear stress, aspirin/LSS combination, and celecoxib/LSS combination were all able to prevent TNFα-induced alterations in eNOS levels and prostacyclin/thromboxane ratio. CONCLUSIONS: Effective strategies to maintain a healthy endothelium, and therefore resistance vessel health, need to include exercise-levels of shear stress to be effective.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Aspirina/farmacologia , Celecoxib/farmacologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Estresse Mecânico , Aterosclerose , Células Cultivadas , Epoprostenol/metabolismo , Exercício Físico , Humanos , Inflamação , Óxido Nítrico Sintase Tipo III/metabolismo , Tromboxano B2/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
12.
Ethn Dis ; 27(3): 233-240, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28811734

RESUMO

PURPOSE: Systemic inflammation, measured by C-reactive protein (CRP), is an important risk factor for cardiovascular disease (CVD) and mortality. We investigated whether aerobic exercise training (AEXT) affects African Americans with high inflammation (HI) the same way it does African Americans with low inflammation (LI) in terms of CVD risk factors. METHODS: 23 African Americans with CRP levels <3 mg/L (LI) and 14 African Americans with CRP ≥3 mg/L (HI) underwent six months of AEXT. Participants were sedentary, non-diabetic, non-smoking, with clinical blood pressure <160/100 mm Hg, were non-hyperlipidemic, had no signs of cardiovascular, renal, or pulmonary disease, and were not on medication. Measures included CD62E+ endothelial microparticles (EMPs), a measure of early stage endothelial dysfunction, as well as lipid and glucose profile, aerobic fitness, body composition, and blood pressure. RESULTS: The LI group improved aerobic fitness by 10%, body mass index by 3%, and plasma triglycerides by 20%, with no change being observed in HI group for these variables. The HI group improved fasting plasma glucose levels by 10%, with no change occurring in the LI group. Both groups improved CD62E+ EMPs by 38% and 59% for the LI and HI group, respectively. CONCLUSIONS: A standard AEXT intervention differentially affected CVD risk factors among African Americans with high and low inflammation. This may indicate that, in African Americans with high inflammation, AEXT alone may not be enough to reap the same benefits as their low-inflammation peers in terms of CVD risk modification.


Assuntos
Negro ou Afro-Americano , Pressão Sanguínea/fisiologia , Proteína C-Reativa/metabolismo , Terapia por Exercício/métodos , Exercício Físico/fisiologia , Inflamação/reabilitação , Triglicerídeos/sangue , Adulto , Idoso , Composição Corporal , Índice de Massa Corporal , Feminino , Humanos , Incidência , Inflamação/sangue , Inflamação/etnologia , Masculino , Pessoa de Meia-Idade , Pennsylvania/epidemiologia , Fatores de Risco
13.
Am J Physiol Heart Circ Physiol ; 312(5): H896-H906, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-28235790

RESUMO

High blood pressure has been shown to elicit impaired dilation in the vasculature. The purpose of this investigation was to elucidate the mechanisms through which high pressure may elicit vascular dysfunction and determine the mechanisms through which regular aerobic exercise protects arteries against high pressure. Male C57BL/6J mice were subjected to 2 wk of voluntary running (~6 km/day) for comparison with sedentary controls. Hindlimb adipose resistance arteries were dissected from mice for measurements of flow-induced dilation (FID; with or without high intraluminal pressure exposure) or protein expression of NADPH oxidase II (NOX II) and superoxide dismutase (SOD). Microvascular endothelial cells were subjected to high physiological laminar shear stress (20 dyn/cm2) or static condition and treated with ANG II + pharmacological inhibitors. Cells were analyzed for the detection of ROS or collected for Western blot determination of NOX II and SOD. Resistance arteries from exercised mice demonstrated preserved FID after high pressure exposure, whereas FID was impaired in control mouse arteries. Inhibition of ANG II or NOX II restored impaired FID in control mouse arteries. High pressure increased superoxide levels in control mouse arteries but not in exercise mouse arteries, which exhibited greater ability to convert superoxide to H2O2 Arteries from exercised mice exhibited less NOX II protein expression, more SOD isoform expression, and less sensitivity to ANG II. Endothelial cells subjected to laminar shear stress exhibited less NOX II subunit expression. In conclusion, aerobic exercise prevents high pressure-induced vascular dysfunction through an improved redox environment in the adipose microvasculature.NEW & NOTEWORTHY We describe potential mechanisms contributing to aerobic exercise-conferred protection against high intravascular pressure. Subcutaneous adipose microvessels from exercise mice express less NADPH oxidase (NOX) II and more superoxide dismutase (SOD) and demonstrate less sensitivity to ANG II. In microvascular endothelial cells, shear stress reduced NOX II but did not influence SOD expression.


Assuntos
Tecido Adiposo/irrigação sanguínea , Tecido Adiposo/fisiologia , Exercício Físico/fisiologia , Microvasos/fisiologia , Estresse Oxidativo/fisiologia , Bloqueadores do Receptor Tipo 2 de Angiotensina II/farmacologia , Animais , Artérias/fisiologia , Pressão Sanguínea/fisiologia , Células Endoteliais/efeitos dos fármacos , Membro Posterior/irrigação sanguínea , Humanos , Masculino , Glicoproteínas de Membrana/antagonistas & inibidores , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , NADPH Oxidase 2 , NADPH Oxidases/antagonistas & inibidores , NADPH Oxidases/genética , Superóxido Dismutase/antagonistas & inibidores , Superóxido Dismutase/genética , Resistência Vascular
14.
Analyst ; 142(8): 1258-1268, 2017 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-27921102

RESUMO

Infrared spectral histopathology has shown great promise as an important diagnostic tool, with the potential to complement current pathological methods. While promising, clinical translation has been hindered by the impracticalities of using infrared transmissive substrates which are both fragile and prohibitively very expensive. Recently, glass has been proposed as a potential replacement which, although largely opaque in the infrared, allows unrestricted access to the high wavenumber region (2500-3800 cm-1). Recent studies using unstained tissue on glass have shown that despite utilising only the amide A band, good discrimination between histological classes could be achieved, and suggest the potential of discriminating between normal and malignant tissue. However unstained tissue on glass has the potential to disrupt the pathologist workflow, since it needs to be stained following infrared chemical imaging. In light of this, we report on the very first infrared Spectral Histopathology SHP study utilising coverslipped H&E stained tissue on glass using samples as received from the pathologist. In this paper we present a rigorous study using results obtained from an extended patient sample set consisting of 182 prostate tissue cores obtained from 100 different patients, on 18 separate H&E slides. Utilising a Random Forest classification model we demonstrate that we can rapidly classify four classes of histology of an independent test set with a high degree of accuracy (>90%). We investigate different degrees of staining using nine separate prostate serial sections, and demonstrate that we discriminate on biomarkers rather than the presence of the stain. Finally, using a four-class model we show that we can discriminate normal epithelium, malignant epithelium, normal stroma and cancer associated stroma with classification accuracies over 95%.


Assuntos
Amarelo de Eosina-(YS) , Hematoxilina , Espectrofotometria Infravermelho , Coloração e Rotulagem , Vidro , Humanos , Masculino , Próstata/diagnóstico por imagem
15.
Am J Hypertens ; 28(7): 900-8, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25499058

RESUMO

BACKGROUND: The disproportionate rates of cardiovascular disease in African Americans may, in part, be due to suboptimal assessment of blood pressure (BP) with clinic BP measurements alone. To date, however, the prevalence of masked hypertension in African Americans has not been fully delineated. The purpose of this study was to evaluate masked hypertension prevalence in a large population-based sample of African Americans and examine its determinants and association with indices of target organ damage (TOD). METHODS: Clinic and 24-hour ambulatory BP monitoring were conducted in 972 African Americans enrolled in the Jackson Heart Study. Common carotid artery intima-media thickness, left ventricular mass index, and the urinary albumin:creatinine excretion ratio were evaluated as indices of TOD. RESULTS: Masked hypertension prevalence was 25.9% in the overall sample and 34.4% in participants with normal clinic BP. All indices of TOD were significantly higher in masked hypertensives compared to sustained normotensives and were similar between masked hypertensives and sustained hypertensives. Male gender, smoking, diabetes, and antihypertensive medication use were independent determinants of masked hypertension in multivariate analyses. CONCLUSIONS: In this population-based cohort of African Americans, approximately one-third of participants with presumably normal clinic BP had masked hypertension when BP was assessed in their daily environment. Masked hypertension was accompanied by a greater degree of TOD in this cohort.


Assuntos
Negro ou Afro-Americano , Pressão Sanguínea , Hipertensão Mascarada/etnologia , Idoso , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Monitorização Ambulatorial da Pressão Arterial , Doenças das Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/etnologia , Doenças das Artérias Carótidas/fisiopatologia , Artéria Carótida Primitiva/diagnóstico por imagem , Espessura Intima-Media Carotídea , Diabetes Mellitus/etnologia , Progressão da Doença , Feminino , Humanos , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Hipertrofia Ventricular Esquerda/etnologia , Hipertrofia Ventricular Esquerda/fisiopatologia , Nefropatias/diagnóstico , Nefropatias/etnologia , Nefropatias/fisiopatologia , Modelos Logísticos , Masculino , Hipertensão Mascarada/diagnóstico , Hipertensão Mascarada/tratamento farmacológico , Hipertensão Mascarada/fisiopatologia , Pessoa de Meia-Idade , Mississippi/epidemiologia , Análise Multivariada , Razão de Chances , Prevalência , Fatores de Risco , Fatores Sexuais , Fumar/efeitos adversos , Fumar/etnologia
17.
World J Gastroenterol ; 18(36): 5051-7, 2012 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-23049213

RESUMO

AIM: To examine the predictive factors of capsule endoscopy (CE) completion rate (CECR) including the effect of inpatient and outpatient status. METHODS: We identified 355 consecutive patients who completed CE at Rush University Medical Center between March 2003 and October 2005. Subjects for CE had either nothing by mouth or clear liquids for the afternoon and evening of the day before the procedure. CE exams were reviewed by two physicians who were unaware of the study hypotheses. After retrospective analysis, 21 cases were excluded due to capsule malfunction, prior gastric surgery, endoscopic capsule placement or insufficient data. Of the remaining 334 exams [264 out-patient (OP), 70 in-patient (IP)], CE indications, findings, location of the patients [IP vs OP and intensive care unit (ICU) vs general medical floor (GMF)] and gastrointestinal transit times were analyzed. Statistical analysis was completed using SPSS version 17 (Chicago, IL). Chi-square, t test or fisher exact-tests were used as appropriate. Multivariate logistic regression analysis was used to identify variables associated with incomplete CE exams. RESULTS: The mean age for the entire study population was 54.7 years. Sixty-one percent of the study population was female, and gender was not different between IPs vs OPs (P = 0.07). The overall incomplete CECR was 14% in our study. Overt obscure gastrointestinal bleeding (OGB) was significantly more common for the IP CE (P = 0.0001), while abdominal pain and assessment of IBD were more frequent indications for the OP CE exams (P = 0.002 and P = 0.01, respectively). Occult OGB was the most common indication and arteriovenous malformations were the most common finding both in the IPs and OPs. The capsule did not enter the small bowel (SB) in 6/70 IPs and 8/264 OPs (P = 0.04). The capsule never reached the cecum in 31.4% (22/70) of IP vs 9.5% (25/ 264) of OP examinations (P < 0.001). The mean gastric transit time (GTT) was delayed in IPs compared to OPs, 98.5 ± 139.5 min vs 60.4 ± 92.6 min (P = 0.008). Minimal SB transit time was significantly prolonged in the IP compared to the OP setting [IP = 275.1 ± 111.6 min vs OP = 244.0 ± 104.3 min (P = 0.037)]. CECR was also significantly higher in the subgroup of patients with OGB who had OP vs IP exams (95% vs 80% respectively, P = 0.001). The proportion of patients with incomplete exams was higher in the ICU (n = 7/13, 54%) as compared to the GMF (n = 15/57, 26%) (P = 0.05). There was only a single permanent SB retention case which was secondary to a previously unknown SB stricture, and the remaining incomplete SB exams were due to slow transit. Medications which affect gastrointestinal system motility were tested both individually and also in aggregate in univariate analysis in hospitalized patients (ICU and GMF) and were not predictive of incomplete capsule passage (P > 0.05). Patient location (IP vs OP) and GTT were independent predictors of incomplete CE exams (P < 0.001 and P = 0.008, respectively). CONCLUSION: Incomplete CE is a multifactorial problem. Patient location and related factors such as severity of illness and sedentary status may contribute to incomplete exams.


Assuntos
Endoscopia por Cápsula , Trânsito Gastrointestinal , Intestino Delgado/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Endoscopia por Cápsula/efeitos adversos , Feminino , Hemorragia Gastrointestinal/etiologia , Humanos , Pacientes Internados , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco
18.
J Biol Chem ; 287(50): 41706-19, 2012 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-23095746

RESUMO

The gustatory system detects tastants and transmits signals to the brain regarding ingested substances and nutrients. Although tastant receptors and taste signaling pathways have been identified, little is known about their regulation. Because bitter, sweet, and umami taste receptors are G protein-coupled receptors (GPCRs), we hypothesized that regulators of G protein signaling (RGS) proteins may be involved. The recent cloning of RGS21 from taste bud cells has implicated this protein in the regulation of taste signaling; however, the exact role of RGS21 has not been precisely defined. Here, we sought to determine the role of RGS21 in tastant responsiveness. Biochemical analyses confirmed in silico predictions that RGS21 acts as a GTPase-accelerating protein (GAP) for multiple G protein α subunits, including adenylyl cyclase-inhibitory (Gα(i)) subunits and those thought to be involved in tastant signal transduction. Using a combination of in situ hybridization, RT-PCR, immunohistochemistry, and immunofluorescence, we demonstrate that RGS21 is not only endogenously expressed in mouse taste buds but also in lung airway epithelial cells, which have previously been shown to express components of the taste signaling cascade. Furthermore, as shown by reverse transcription-PCR, the immortalized human airway cell line 16HBE was found to express transcripts for tastant receptors, RGS21, and downstream taste signaling components. Over- and underexpression of RGS21 in 16HBE cells confirmed that RGS21 acts to oppose bitter tastant signaling to cAMP and calcium second messenger changes. Our data collectively suggests that RGS21 modulates bitter taste signal transduction.


Assuntos
Sinalização do Cálcio/fisiologia , AMP Cíclico/metabolismo , Reguladores de Proteínas de Ligação ao GTP/biossíntese , Mucosa Respiratória/metabolismo , Papilas Gustativas/metabolismo , Paladar/fisiologia , Animais , Células COS , Cálcio/metabolismo , Chlorocebus aethiops , AMP Cíclico/genética , Reguladores de Proteínas de Ligação ao GTP/genética , Humanos , Camundongos , Camundongos Transgênicos , Proteínas RGS , Mucosa Respiratória/citologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Papilas Gustativas/citologia
19.
Mol Cancer Res ; 10(10): 1282-93, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22936788

RESUMO

A disintegrin and metalloproteinases (ADAMs) and matrix metalloproteinases (MMPs) are zinc metalloproteinases (ZMPs) that catalyze the "ectodomain shedding" of a range of cell surface proteins including signaling and adhesion molecules. These "sheddases" are associated with the invasion and metastasis of a range of cancers. Increased serum and tumor tissue levels of copper are also observed in several cancers, although little is known about how the metal might promote disease progression at the molecular level. In the current study, we investigated whether copper might regulate the ectodomain shedding of two key cell surface proteins implicated in the invasion and metastasis of prostate cancer, the Notch ligand Jagged1 and the adhesion molecule E-cadherin, and whether the metal was able to influence the invasion of the prostate cancer epithelial cell line PC3. Physiological copper concentrations stimulated the ZMP-mediated proteolysis of Jagged1 and E-cadherin in cell culture models, whereas other divalent metals had no effect. Copper-mediated Jagged1 proteolysis was also observed following the pretreatment of cells with cycloheximide and in a cell-free membrane system, indicating a posttranslational mechanism of sheddase activation. Finally, the concentrations of copper that stimulated ZMP-mediated protein shedding also enhanced PC3 invasion; an effect that could be negated using a sheddase inhibitor or copper chelators. Collectively, these data implicate copper as an important factor in promoting prostate cancer cell invasion and indicate that the selective posttranslational activation of ZMP-mediated protein shedding might play a role in this process.


Assuntos
Moléculas de Adesão Celular/metabolismo , Cobre/farmacologia , Células Epiteliais/patologia , Proteínas de Membrana/metabolismo , Metaloendopeptidases/metabolismo , Neoplasias da Próstata/patologia , Transdução de Sinais/efeitos dos fármacos , Precursor de Proteína beta-Amiloide/metabolismo , Caderinas/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Cátions Bivalentes/farmacologia , Linhagem Celular Tumoral , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células HEK293 , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Proteína Jagged-1 , Masculino , Invasividade Neoplásica , Neoplasias da Próstata/metabolismo , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Estrutura Terciária de Proteína , Proteólise/efeitos dos fármacos , Proteínas Serrate-Jagged
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