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1.
Am J Otolaryngol ; 44(2): 103781, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36640532

RESUMO

OBJECTIVE: Osteoradionecrosis (ORN) of the mandible is a devastating complication of external beam radiation therapy (EBRT) for head and neck squamous cell carcinoma (HNSCC). We sought to ascertain ORN risk in a Veteran HNSCC population treatment with definitive or adjuvant EBRT and followed prospectively. STUDY DESIGN: Retrospective analysis of prospective cohort. SETTING: Tertiary care Veterans Health Administration (VHA) medical center. METHODS: Patients with HNSCC who initiated treatment at the Michael E. DeBakey Veterans Affairs Medical Center (MEDVAMC) are prospectively tracked for quality of care purposes through the end of the cancer surveillance period (5 years post treatment completion). We retrospectively analyzed this patient cohort and extracted clinical and pathologic data for 164 patients with SCC of the oral cavity, oropharynx, larynx, and hypopharynx who received definitive or adjuvant EBRT (2016-2020). RESULTS: Most patients were dentate and 80 % underwent dental extractions prior to EBRT of which 16 (16 %) had complications. The rate of ORN was 3.7 % for oral cavity SCC patients and 8.1 % for oropharyngeal SCC patients. Median time to ORN development was 156 days and the earliest case was detected at 127 days post EBRT completion. All ORN patients were dentate and underwent extraction prior to EBRT start. CONCLUSION: ORN development can occur early following EBRT in a Veteran population with significant comorbid conditions but overall rates are in line with the general population. Prospective tracking of HNSCC patients throughout the post-treatment surveillance period is critical to early detection of this devastating EBRT complication.


Assuntos
Neoplasias de Cabeça e Pescoço , Osteorradionecrose , Veteranos , Humanos , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço/radioterapia , Carcinoma de Células Escamosas de Cabeça e Pescoço/epidemiologia , Osteorradionecrose/diagnóstico , Osteorradionecrose/epidemiologia , Osteorradionecrose/etiologia , Estudos Prospectivos , Detecção Precoce de Câncer , Mandíbula , Neoplasias de Cabeça e Pescoço/epidemiologia , Neoplasias de Cabeça e Pescoço/radioterapia , Neoplasias de Cabeça e Pescoço/complicações , Comorbidade
2.
Mod Pathol ; 35(8): 1045-1054, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35184149

RESUMO

Oropharyngeal squamous cell carcinoma (OPSCC), largely fueled by the human papillomavirus (HPV), has a complex biological and immunologic phenotype. Although HPV/p16 status can be used to stratify OPSCC patients as a function of survival, it remains unclear what drives an improved treatment response in HPV-associated OPSCC and whether targetable biomarkers exist that can inform a precision oncology approach. We analyzed OPSCC patients treated between 2000 and 2016 and correlated locoregional control (LRC), disease-free survival (DFS) and overall survival (OS) with conventional clinical parameters, risk parameters generated using deep-learning algorithms trained to quantify tumor-infiltrating lymphocytes (TILs) (OP-TIL) and multinucleated tumor cells (MuNI) and targeted transcriptomics. P16 was a dominant determinant of LRC, DFS and OS, but tobacco exposure, OP-TIL and MuNI risk features correlated with clinical outcomes independent of p16 status and the combination of p16, OP-TIL and MuNI generated a better stratification of OPSCC risk compared to individual parameters. Differential gene expression (DEG) analysis demonstrated overlap between MuNI and OP-TIL and identified genes involved in DNA repair, oxidative stress response and tumor immunity as the most prominent correlates with survival. Alteration of inflammatory/immune pathways correlated strongly with all risk features and oncologic outcomes. This suggests that development of OPSCC consists of an intersection between multiple required and permissive oncogenic and immunologic events which may be mechanistically linked. The strong relationship between tumor immunity and oncologic outcomes in OPSCC regardless of HPV status may provide opportunities for further biomarker development and precision oncology approaches incorporating immune checkpoint inhibitors for maximal anti-tumor efficacy.


Assuntos
Neoplasias de Cabeça e Pescoço , Neoplasias Orofaríngeas , Infecções por Papillomavirus , Inibidor p16 de Quinase Dependente de Ciclina/análise , Humanos , Neoplasias Orofaríngeas/patologia , Papillomaviridae , Infecções por Papillomavirus/patologia , Medicina de Precisão , Prognóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço
3.
Orbit ; 41(6): 786-790, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34078220

RESUMO

Orbital metastasis of urothelial carcinoma is very rare; only 22 cases have been documented. In this case report, we describe a patient 1 month status post transurethral resection of urothelial carcinoma who presented with a clinical picture suggestive of orbital cellulitis. However, neither broad-spectrum antibiotics nor a subsequent trial of methylprednisolone was effective at relieving the patient's symptoms. CT imaging of the head, chest, abdomen, pelvis, and lower extremity showed no signs of metastatic disease. Six days after presentation, punch biopsy of the mass was performed and confirmed urothelial carcinoma metastatic to the orbit. The patient died 3 months later due to multiple sites of distant metastasis. This case report suggests that a high index of suspicion for orbital metastasis is important for patients with a history of urothelial carcinoma with new and acute onset of ocular symptoms and emphasizes the need for urgent systemic evaluation and treatment.


Assuntos
Carcinoma de Células de Transição , Neoplasias Orbitárias , Neoplasias da Bexiga Urinária , Humanos , Carcinoma de Células de Transição/diagnóstico por imagem , Carcinoma de Células de Transição/terapia , Neoplasias da Bexiga Urinária/diagnóstico por imagem , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias Orbitárias/diagnóstico por imagem , Neoplasias Orbitárias/terapia , Órbita/diagnóstico por imagem , Órbita/patologia , Biópsia
4.
Anal Chem ; 93(25): 8754-8763, 2021 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-34125535

RESUMO

To tackle the COVID-19 outbreak, which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), there is an unmet need for highly accurate diagnostic tests at all stages of infection with rapid results and high specificity. Here, we present a label-free nanoplasmonic biosensor-based, multiplex screening test for COVID-19 that can quantitatively detect 10 different biomarkers (6 viral nucleic acid genes, 2 spike protein subunits, and 2 antibodies) with a limit of detection in the aM range, all within one biosensor platform. Our newly developed nanoplasmonic biosensors demonstrate high specificity, which is of the upmost importance to avoid false responses. As a proof of concept, we show that our detection approach has the potential to quantify both IgG and IgM antibodies directly from COVID-19-positive patient plasma samples in a single instrument run, demonstrating the high-throughput capability of our detection approach. Most importantly, our assay provides receiving operating characteristics, areas under the curve of 0.997 and 0.999 for IgG and IgM, respectively. The calculated p-value determined through the Mann-Whitney nonparametric test is <0.0001 for both antibodies when the test of COVID-19-positive patients (n = 80) is compared with that of healthy individuals (n = 72). Additionally, the screening test provides a calculated sensitivity (true positive rate) of 100% (80/80), a specificity (true negative rate) >96% (77/80), a positive predictive value of 98% at 5% prevalence, and a negative predictive value of 100% at 5% prevalence. We believe that our very sensitive, multiplex, high-throughput testing approach has potential applications in COVID-19 diagnostics, particularly in determining virus progression and infection severity for clinicians for an appropriate treatment, and will also prove to be a very effective diagnostic test when applied to diseases beyond the COVID-19 pandemic.


Assuntos
Técnicas Biossensoriais , COVID-19 , Anticorpos Antivirais , Humanos , Imunoglobulina G , Imunoglobulina M , Pandemias , RNA , SARS-CoV-2 , Sensibilidade e Especificidade , Glicoproteína da Espícula de Coronavírus
5.
Biomed Eng Online ; 15(Suppl 2): 156, 2016 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-28155699

RESUMO

BACKGROUND: Wall shear stress (WSS) is involved in the pathophysiology of atherosclerosis. The correlation between WSS and atherosclerosis can be investigated over time using a WSS-manipulated atherosclerotic mouse model. To determine WSS in vivo, detailed 3D geometry of the vessel network is required. However, a protocol to reconstruct 3D murine vasculature using this animal model is lacking. In this project, we evaluated the adequacy of eXIA 160, a small animal contrast agent, for assessing murine vascular network on micro-CT. Also, a protocol was established for vessel geometry segmentation and WSS analysis. METHODS: A tapering cast was placed around the right common carotid artery (RCCA) of ApoE-/- mice (n = 8). Contrast-enhanced micro-CT was performed using eXIA 160. An innovative local threshold-based segmentation procedure was implemented to reconstruct 3D geometry of the RCCA. The reconstructed RCCA was compared to the vessel geometry using a global threshold-based segmentation method. Computational fluid dynamics was applied to compute the velocity field and WSS distribution along the RCCA. RESULTS: eXIA 160-enhanced micro-CT allowed clear visualization and assessment of the RCCA in all eight animals. No adverse biological effects were observed from the use of eXIA 160. Segmentation using local threshold values generated more accurate RCCA geometry than the global threshold-based approach. Mouse-specific velocity data and the RCCA geometry generated 3D WSS maps with high resolution, enabling quantitative analysis of WSS. In all animals, we observed low WSS upstream of the cast. Downstream of the cast, asymmetric WSS patterns were revealed with variation in size and location between animals. CONCLUSIONS: eXIA 160 provided good contrast to reconstruct 3D vessel geometry and determine WSS patterns in the RCCA of the atherosclerotic mouse model. We established a novel local threshold-based segmentation protocol for RCCA reconstruction and WSS computation. The observed differences between animals indicate the necessity to use mouse-specific data for WSS analysis. For our future work, our protocol makes it possible to study in vivo WSS longitudinally over a growing plaque.


Assuntos
Artérias Carótidas/diagnóstico por imagem , Artérias Carótidas/fisiopatologia , Meios de Contraste/química , Microtomografia por Raio-X/métodos , Animais , Apolipoproteínas E/genética , Velocidade do Fluxo Sanguíneo , Vasos Coronários/patologia , Células Endoteliais/citologia , Endotélio Vascular/fisiopatologia , Feminino , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Camundongos , Camundongos Endogâmicos C57BL , Resistência ao Cisalhamento , Estresse Mecânico
6.
Mol Imaging ; 142015.
Artigo em Inglês | MEDLINE | ID: mdl-26044776

RESUMO

Recently, an apolipoprotein E-deficient (ApoE-/-) mouse model with a mutation (C1039G+/-) in the fibrillin-1 (Fbn1) gene (ApoE-/-Fbn1C1039G+/- mouse model) was developed showing vulnerable atherosclerotic plaques, prone to rupture, in contrast to the ApoE-/- mouse model, where mainly stable plaques are present. One indicator of plaque vulnerability is the level of macrophage infiltration. Therefore, this study aimed to measure and quantify in vivo the macrophage infiltration related to plaque development and progression. For this purpose, 5-weekly consecutive gold nanoparticle-enhanced micro-computed tomography (microCT) scans were acquired. Histology confirmed that the presence of contrast agent coincided with the presence of macrophages. Based on the microCT scans, regions of the artery wall with contrast agent present were calculated and visualized in three dimensions. From this information, the contrast-enhanced area and contrast-enhanced centerline length were calculated for the branches of the carotid bifurcation (common, external, and internal carotid arteries). Statistical analysis showed a more rapid development and a larger extent of plaques in the ApoE-/-Fbn1C1039G+/- compared to the ApoE-/- mice. Regional differences between the branches were also observable and quantifiable. We developed and applied a methodology based on gold particle-enhanced microCT to visualize the presence of macrophages in atherosclerotic plaques in vivo.


Assuntos
Ouro/química , Placa Aterosclerótica/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Animais , Artérias/patologia , Meios de Contraste , Modelos Animais de Doenças , Feminino , Camundongos , Reprodutibilidade dos Testes
7.
Qual Health Res ; 23(8): 1138-52, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23774630

RESUMO

Collaborative working is a crucial part of contemporary health and social care. Researching the experiences of those involved--as professionals, patients, or carers--is challenging, given the complexity of many cases and the taken-for-granted nature of roles and identities in relation to it. In this article we introduce the Pictor technique for exploring experiences of collaborative working. This is a visual technique in which participants construct a representation of roles and relationships in a particular case using arrow-shaped adhesive notes or cards. The chart so produced helps the participant tell the story of his or her experience and serves as a focus for further exploration with the researcher. We describe the background to Pictor and illustrate its use with professionals, patients, and carers, drawing on recent and current research. We examine how Pictor relates to other visual methods, and conclude by considering how the technique might be developed in the future.


Assuntos
Cuidadores/organização & administração , Atenção à Saúde/organização & administração , Pesquisa sobre Serviços de Saúde/organização & administração , Relações Interprofissionais , Equipe de Assistência ao Paciente/organização & administração , Pesquisa Qualitativa , Técnicas Sociométricas , Atitude do Pessoal de Saúde , Atitude Frente a Saúde , Cuidadores/normas , Comportamento Cooperativo , Atenção à Saúde/métodos , Pesquisa sobre Serviços de Saúde/métodos , Humanos , Entrevistas como Assunto/métodos , Modelos Organizacionais , Equipe de Assistência ao Paciente/normas , Relações Profissional-Família , Relações Profissional-Paciente , Recursos Humanos
8.
Trauma Violence Abuse ; : 15248380231196108, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37702188

RESUMO

Intimate partner abuse (IPA) is widespread, and denial, minimization, justifying, and blaming (DMJB) are common among people who have committed IPA. Views on the function of DMJB in IPA are mixed, often based on the theoretical standpoint of the authors. This systematic review brings together the knowledge of how distorted accounts operate in IPA committed by men. A systematic review of primary research related to DMJB in heterosexual men who have committed to IPA was conducted. In all, 31 papers were found to meet the inclusion criteria (adult, male-to-female abuse, in western culture, peer reviewed and published in English) and were quality appraised. Data were extracted and analyzed using narrative synthesis. The findings indicate the way DMJB operates in this group is complex. It can represent facilitators of abusive behavior, a way to protect the individual's identity and self-esteem, and a tool men use instrumentally to achieve goals. Themes were present within and between studies highlighting the complex function of DMJB. A model representing the hypothesized intertwined function of DMJB for IPA is proposed. The limitations of the review are discussed and implications and recommendations for policy, practice, and future research are proposed.

9.
Cancers (Basel) ; 15(23)2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-38067198

RESUMO

Surgery and external-beam radiation therapy are the primary treatment modalities for locally advanced NMSC, but they can lead to impairment of function and disfigurement in sensitive areas such as the head and neck. With the advent of targeted systemic therapies and immunotherapy, physicians have explored the ability to offer neoadjuvant therapy for NMSC in order to reduce surgically induced morbidity. Provided herein is a guide to current applications of neoadjuvant systemic therapies for NMSC and future directions.

10.
Laryngoscope Investig Otolaryngol ; 8(4): 895-902, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37621289

RESUMO

Objective: Cisplatin forms the backbone of systemic chemotherapy treatment for oropharyngeal squamous cell carcinoma (OPSCC). The ideal cisplatin dosing regimen remains yet to be fully defined for achieving optimal efficacy and toxicity profiles in patients with comorbidity. Methods: We retrospectively reviewed oncologic and toxicity data for patients with OPSCC treated at the Michael E. DeBakey Veterans Affairs Medical Center between 2000 and 2020 who initiated curative intent, definitive chemo-radiation with one of three single agent regimens: high dose (HD) cisplatin, low dose (LD) cisplatin or cetuximab. Results: Patients with HPV-associated tumors and nonsmokers demonstrated improved overall and disease-free survival along with locoregional and distant metastatic control regardless of chemotherapy regimen. Regardless of regimen selection, patients which received a cumulative cisplatin dose ≥200 mg/m2 had a lower rate of distant metastasis. The HD regimen resulted in a greater fraction (75% vs. 50%) of patients receiving a cumulative cisplatin dose ≥200 mg/m2 and a comparable measured toxicity burden compared to the LD regimen. Conclusions: Both HD and LD cisplatin regimens can be safely delivered to a Veteran OPSCC patient population which should allow for straightforward application of conclusions drawn from completed and active clinical trials testing cisplatin regimens. Level of Evidence: 4.

11.
Otolaryngol Head Neck Surg ; 162(6): 888-896, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32093532

RESUMO

OBJECTIVE: Advanced laryngeal squamous cell carcinoma remains associated with approximately 50% mortality at 5 years. Delivery of multimodality treatment remains critical to maximizing survival for this disease, but achieving this at a national level remains a difficult undertaking, particularly in under- and uninsured patients as well as minority patients. We sought to evaluate laryngeal cancer treatment delivery and clinical outcomes in a predominantly minority and underserved cohort of largely under- and uninsured patients in a county hospital. STUDY DESIGN: Retrospective cohort study. SETTING: Tertiary care county hospital in Houston, Texas. SUBJECTS AND METHODS: Patients (N = 210) with a new diagnosis of laryngeal squamous cell carcinoma treated between 2005 and 2015 were included in a retrospective analysis of patient demographics, tumor and treatment characteristics, and oncologic outcomes. RESULTS: The majority of patients presented with advanced disease (T4 = 43%, N>0 = 45%). Treatment selection was compliant with National Comprehensive Cancer Network guidelines in 81% of cases, but 76% of patients who required adjuvant radiotherapy were unable to start it within 6 weeks postsurgery. Overall survival and disease-free survival were 52% and 63% for the entire cohort, respectively. Supraglottic subsite and nodal metastases were significantly associated with decreased overall survival and disease-free survival. Race/ethnicity and insurance status were not associated with worse oncologic outcomes. CONCLUSION: Under- and uninsured patients often present with advanced laryngeal cancer. Oncologic outcomes in this cohort of patients is similar to that of other published series. Moreover, tumor characteristics rather than demographic variables drive oncologic outcomes for the predominantly minority and underserved patients seeking care in our tertiary care county hospital.


Assuntos
Carcinoma de Células Escamosas/epidemiologia , Neoplasias Laríngeas/epidemiologia , Grupos Minoritários , Estadiamento de Neoplasias , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/terapia , Terapia Combinada , Intervalo Livre de Doença , Seguimentos , Humanos , Neoplasias Laríngeas/diagnóstico , Neoplasias Laríngeas/terapia , Pessoa de Meia-Idade , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Texas/epidemiologia
12.
Laryngoscope Investig Otolaryngol ; 4(6): 617-623, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31890879

RESUMO

OBJECTIVES: Oropharyngeal squamous cell carcinoma (OPSCC) incidence is rapidly increasing in the United States and around the world, driven in large part by infection with the human papillomavirus (HPV). HPV associated OPSCC (HPV+OPSCC) has been shown to have improved response to treatment relative to tobacco-associated OPSCC. However, improvement in patient survival has not been uniform. Subsets of OPSCC patients in the US and around the world continue to have poor oncologic outcomes. Although the drivers of this phenomenon remain unclear, there is increasing evidence that tobacco exposure plays an important role in modulating HPV+OPSCC clinical outcomes. METHODS: We conducted a review of the literature. RESULTS: We discuss the potential biological and epidemiological interplay between tobacco and HPV exposure in the context of OPSCC. Multiple retrospective and prospective cohorts show that HPV+OPSCC patients with a history of tobacco exposure have response to treatment and clinical outcomes distinct from HPV+OPSCC non-smokers which poses clinical and scientific challenges to be addressed over the next decade. CONCLUSIONS: The interaction between tobacco exposure and HPV infection in the context of OPSCC has significant implications for both standard of care treatment regimens and development of novel therapeutic approaches, in particular those which incorporate immunomodulatory agents. LEVEL OF EVIDENCE: 5.

13.
Int J Integr Care ; 17(4): 3, 2017 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-28970761

RESUMO

BACKGROUND: Collaborative working between professionals is a key component of integrated care. The academic literature on it largely focuses either on integration between health and social care or on the dynamics of power and identity between doctors and nurses. With the proliferation and extension of nursing roles, there is a need to examine collaborative working amongst different types of nurses. METHOD: This study explored experiences of collaborative working amongst generalist and specialist nurses, in community and acute settings. We carried out semi-structured interviews, incorporating the Pictor technique, with 45 nurses, plus 33 other key stakeholders. Transcripts were analysed using Template Analysis. This article focuses on one major thematic area that emerged from the analysis: the significance of interpersonal relationships amongst nurses, and between them and other professionals, patients and carers. RESULTS: Relationship issues were ubiquitous in participants' accounts of collaborative working. Good personal relationships facilitated collaboration; face-to-face interaction was especially valued. Relationships were recognized as requiring effort, especially in new roles. Organisational changes could disrupt productive personal networks. CONCLUSION: Relationship issues are integral to successful collaborative working. Policy and practice leaders must take this into account in future service developments. Further research into collaborative relationships in different settings is needed.

14.
Ann Biomed Eng ; 44(8): 2327-2338, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26695938

RESUMO

It is generally accepted that low and oscillatory wall shear stress favors the initiation and development of atherosclerosis. However, a quantitative analysis of the association between shear stress metrics at baseline and lesion prevalence at a later stage is challenging to perform in vivo on a within-subject basis. In this study, we assessed carotid hemodynamics and derived hemodynamic wall parameters from subject-specific fluid-structure interaction simulations in the left and right carotid arteries of 4 ApoE(-/-) mice prior to disease development. We then applied a point-by-point quantitative association (surrogate sample data analysis) between various established and more recent shear related parameters and the extent of macrophage infiltration at a later stage. We conclude that, for the atherosclerotic murine carotid bifurcation, (i) there is an association between hemodynamics and macrophage infiltration; (ii) this correlation is most apparent when assessed at the level of the entire carotid bifurcation; (iii) the strongest spatial correlation between hemodynamics and atherosclerosis development was found for the time averaged wall shear stress (negative correlation) and the relative residence time (positive correlation); (iv) aggregating the data leads to an overestimation of the correlation.


Assuntos
Aterosclerose/fisiopatologia , Artérias Carótidas/fisiopatologia , Hemodinâmica , Modelos Cardiovasculares , Resistência ao Cisalhamento , Estresse Mecânico , Animais , Apolipoproteínas E/deficiência , Aterosclerose/genética , Aterosclerose/metabolismo , Aterosclerose/patologia , Artérias Carótidas/metabolismo , Artérias Carótidas/patologia , Modelos Animais de Doenças , Macrófagos/metabolismo , Macrófagos/patologia , Camundongos , Camundongos Knockout
15.
J Biomech ; 49(13): 2741-2747, 2016 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-27342001

RESUMO

BACKGROUND: Low and oscillatory wall shear stresses (WSS) near aortic bifurcations have been linked to the onset of atherosclerosis. In previous work, we calculated detailed WSS patterns in the carotid bifurcation of mice using a Fluid-structure interaction (FSI) approach. We subsequently fed the animals a high-fat diet and linked the results of the FSI simulations to those of atherosclerotic plaque location on a within-subject basis. However, these simulations were based on boundary conditions measured under anesthesia, while active mice might experience different hemodynamics. Moreover, the FSI technique for mouse-specific simulations is both time- and labor-intensive, and might be replaced by simpler and easier Computational Fluid Dynamics (CFD) simulations. The goal of the current work was (i) to compare WSS patterns based on anesthesia conditions to those representing active resting and exercising conditions; and (ii) to compare WSS patterns based on FSI simulations to those based on steady-state and transient CFD simulations. METHODS: For each of the 3 computational techniques (steady state CFD, transient CFD, FSI) we performed 5 simulations: 1 for anesthesia, 2 for conscious resting conditions and 2 more for conscious active conditions. The inflow, pressure and heart rate were scaled according to representative in vivo measurements obtained from literature. RESULTS: When normalized by the maximal shear stress value, shear stress patterns were similar for the 3 computational techniques. For all activity levels, steady state CFD led to an overestimation of WSS values, while FSI simulations yielded a clear increase in WSS reversal at the outer side of the sinus of the external carotid artery that was not visible in transient CFD-simulations. Furthermore, the FSI simulations in the highest locomotor activity state showed a flow recirculation zone in the external carotid artery that was not present under anesthesia. This recirculation went hand in hand with locally increased WSS reversal. CONCLUSIONS: Our data show that FSI simulations are not necessary to obtain normalized WSS patterns, but indispensable to assess the oscillatory behavior of the WSS in mice. Flow recirculation and WSS reversal at the external carotid artery may occur during high locomotor activity while they are not present under anesthesia. These phenomena might thus influence plaque formation to a larger extent than what was previously assumed.


Assuntos
Anestesia , Artéria Carótida Externa/efeitos dos fármacos , Artéria Carótida Interna/efeitos dos fármacos , Hidrodinâmica , Modelos Cardiovasculares , Resistência ao Cisalhamento/efeitos dos fármacos , Estresse Mecânico , Animais , Artéria Carótida Externa/fisiologia , Artéria Carótida Interna/fisiologia , Simulação por Computador , Feminino , Hemodinâmica , Camundongos
16.
J Biomech ; 49(11): 2135-2142, 2016 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-26655592

RESUMO

The ApoE(-)(/)(-) mouse is a common small animal model to study atherosclerosis, an inflammatory disease of the large and medium sized arteries such as the carotid artery. It is generally accepted that the wall shear stress, induced by the blood flow, plays a key role in the onset of this disease. Wall shear stress, however, is difficult to derive from direct in vivo measurements, particularly in mice. In this study, we integrated in vivo imaging (micro-Computed Tomography-µCT and ultrasound) and fluid-structure interaction (FSI) modeling for the mouse-specific assessment of carotid hemodynamics and wall shear stress. Results were provided for 8 carotid bifurcations of 4 ApoE(-)(/)(-) mice. We demonstrated that accounting for the carotid elasticity leads to more realistic flow waveforms over the complete domain of the model due to volume buffering capacity in systole. The 8 simulated cases showed fairly consistent spatial distribution maps of time-averaged wall shear stress (TAWSS) and relative residence time (RRT). Zones with reduced TAWSS and elevated RRT, potential indicators of atherosclerosis-prone regions, were located mainly at the outer sinus of the external carotid artery. In contrast to human carotid hemodynamics, no flow recirculation could be observed in the carotid bifurcation region.


Assuntos
Modelos Cardiovasculares , Resistência ao Cisalhamento , Estresse Mecânico , Animais , Apolipoproteínas E/deficiência , Aterosclerose/fisiopatologia , Artéria Carótida Externa/diagnóstico por imagem , Artéria Carótida Externa/fisiologia , Artéria Carótida Interna/diagnóstico por imagem , Artéria Carótida Interna/fisiologia , Simulação por Computador , Elasticidade , Feminino , Hemodinâmica , Camundongos , Microtomografia por Raio-X
17.
Nurs Times ; 98(33): 32-3, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12211765

RESUMO

There is increasing cooperation between NHS service providers and patients, who provide feedback on the care they receive and make suggestions for research and changes in practice. This article discusses why such links are necessary and describes the cancer research open day organised by a cancer network as one example of a forum for such exchanges of information to take place. The authors believe this example of collaborative interaction between patients and health professionals can be adapted and used by nurses working in a variety of health care settings.


Assuntos
Institutos de Câncer/organização & administração , Neoplasias/terapia , Participação do Paciente , Pesquisa , Retroalimentação , Humanos , Medicina Estatal
18.
IEEE Trans Biomed Eng ; 59(12): 3293-303, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22588575

RESUMO

Due to the growing shortage of donor livers, more patients are waiting for transplantation. Living donor liver transplantation may help expanding the donor pool, but is often confronted with the small-for-size syndrome. Since the hemodynamic effects of partial hepatectomy are not fully understood, we developed an electrical rat liver model to compare normal with resected liver hemodynamics. Detailed geometrical data and 3-D reconstructions of the liver vasculature of two rats were gathered by combining vascular corrosion casting, micro-CT scanning, and image processing. Data extrapolations allowed obtaining a total liver pressure- and flow-driven electrical analog. Subsequently, virtual resections led to 70%, 80%, or 90% partial hepatectomy models. Results demonstrated hyperperfusion effects such as portal hypertension and elevated lobe-specific portal venous flows (11, 12, and 24 mmHg, and 1.0-3.0, 1.8-3.5, and 7.4 ml/min for 70%, 80%, and 90% hepatectomy, respectively). Comparison of two 90% resection techniques demonstrated different total arterial flows (0.28 ml/min versus 0.61 ml/min), portal (24 mmHg versus 21 mmHg), and sinusoidal pressures (14 mmHg versus 9.5-12 mmHg), probably leading to better survival for lower portal and sinusoidal pressures. Toward the future, the models may be extrapolated to human livers and help us to optimize hepatectomy planning.


Assuntos
Hepatectomia , Artéria Hepática/anatomia & histologia , Veias Hepáticas/anatomia & histologia , Circulação Hepática/fisiologia , Fígado/irrigação sanguínea , Modelos Biológicos , Animais , Engenharia Biomédica , Feminino , Hemodinâmica/fisiologia , Artéria Hepática/diagnóstico por imagem , Artéria Hepática/fisiologia , Veias Hepáticas/diagnóstico por imagem , Veias Hepáticas/fisiologia , Humanos , Imageamento Tridimensional , Fígado/anatomia & histologia , Fígado/diagnóstico por imagem , Modelos Animais , Ratos , Ratos Wistar , Microtomografia por Raio-X
19.
Health Expect ; 6(1): 81-8, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12603631

RESUMO

INTRODUCTION: Within the last decade, there have been many government initiatives to promote consumer involvement in research, especially in cancer. At the same time, the number and influence of consumer groups themselves have expanded. However, the organizational infrastructure necessary to facilitate consumer involvement has not been developed. Consequently, consumer involvement has tended to remain essentially localized and project driven, with no strategic or regional lead. OPPORTUNITIES FOR INVOLVEMENT AND IDENTIFICATION OF CONSUMERS: The opportunities for consumers to influence the research process at each stage of the research process are identified. The different types of consumer involvement are also examined. Novel ways of identifying and recruiting consumers that have been adopted by one cancer network are discussed. THE STRATEGIES USED IN ONE CANCER NETWORK: An organizational model designed by one cancer network for involving consumers in research is illustrated. Three innovations are examined in detail. First, how three open consumer conferences have increased awareness of research among service users. Second, the recruitment of consumers to sit on project steering groups and a committee that provides a strategic overview of current research. Third, the establishment of a Consumer Panel for Research where reimbursed, trained consumers are able to provide a considered consumer perspective in a range of settings. CONCLUSIONS: Cancer networks need to take the lead in the development of an organizational infrastructure to facilitate consumer involvement. The model developed in Sheffield could be generalizable to other diseases and other health-care settings.


Assuntos
Pesquisa Biomédica , Institutos de Câncer/organização & administração , Participação da Comunidade , Neoplasias , Ensaios Clínicos como Assunto , Associações de Consumidores , Humanos , Seleção de Pacientes , Medicina Estatal , Reino Unido
20.
Palliat Med ; 17(6): 482-90, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14526880

RESUMO

Between October 2001 and May 2002 the Chairperson and Vice-Chairperson of each Multicentre Research Ethics Committee (MREC) in England, Wales and Scotland took part in a semi-structured interview to ascertain the attitudes of MRECs to palliative care research. Interviews were transcribed and analysed using a grounded theory approach. Most respondents said each protocol was reviewed on its own merits, according to broad ethical principles, but were equivocal as to whether palliative care protocols posed particular or different challenges compared to those from other specialties. Respondents said they reviewed only a small number of palliative care protocols, and that they were less experienced with some of the study methods utilized, particularly qualitative designs. Four main themes emerged from the analysis. Respondents expressed concerns about the protocol itself--in regard to safeguarding the principles of autonomy and justice. There were concerns about how the research would be carried out, especially the protection of patients and the influence and input of the researcher in the process. The third theme concerned the impact of the research on the participant, particularly intrusion, potential distress and the existence of support mechanisms. Fourthly, respondents identified patient groups receiving palliative care (children, the elderly, bereaved families, patients in intensive therapy units, and those from ethnic groupings), who they considered might be particularly vulnerable.


Assuntos
Pesquisa Biomédica/ética , Cuidados Paliativos/ética , Atitude do Pessoal de Saúde , Comitês de Ética em Pesquisa , Humanos , Estudos Multicêntricos como Assunto
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