Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 16 de 16
Filtrar
1.
Biomed Microdevices ; 26(2): 25, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38780704

RESUMO

Particle classification plays a crucial role in various scientific and technological applications, such as differentiating between bacteria and viruses in healthcare applications or identifying and classifying cancer cells. This technique requires accurate and efficient analysis of particle properties. In this study, we investigated the integration of electrical and optical features through a multimodal approach for particle classification. Machine learning classifier algorithms were applied to evaluate the impact of combining these measurements. Our results demonstrate the superiority of the multimodal approach over analyzing electrical or optical features independently. We achieved an average test accuracy of 94.9% by integrating both modalities, compared to 66.4% for electrical features alone and 90.7% for optical features alone. This highlights the complementary nature of electrical and optical information and its potential for enhancing classification performance. By leveraging electrical sensing and optical imaging techniques, our multimodal approach provides deeper insights into particle properties and offers a more comprehensive understanding of complex biological systems.


Assuntos
Aprendizado de Máquina , Imagem Óptica , Algoritmos
2.
Cureus ; 16(2): e55139, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38558573

RESUMO

BACKGROUND: Reports on the outcomes following instrumented anterior lumbar interbody fusion (ALIF) with anterior plate fixation are limited. The aim of this study was to assess the clinical and radiographic outcomes of patients undergoing ALIF with anterior plate fixation.  Methods: Medical records and radiographic imaging were reviewed for 100 patients who received ALIF with anterior plate fixation between 2008 to 2021 and completed at least one year of follow-up and postoperative imaging. Prospectively collected patient data included indication for surgery, BMI, age, number and location of levels treated, complications, reoperation rates, fusion rate, and measurements of global lordosis, disc space height, and segmental angulation.  Results: A total of 100 patients were included in this study. The mean length of follow-up was 81.37 months. Changes in preoperative-to-postoperative Oswestry Disability Index (ODI) and Visual Analog Score (VAS) demonstrated improvements of 30.86% and 18.56%, respectively. Major vascular injuries occurred in 3% of the cases. A hardware failure rate of 5% was observed. The reoperation rate was 10%. The radiographic fusion rate derived from computed tomography (CT) and plain film was 95.45% and 88.87%, respectively. Postoperative global lordosis demonstrated a 6.08% increase. Postoperative segmental angulation measurements increased by 57.74%. No statistically significant differences in clinical or radiographic outcomes were observed based on the spine level of fusion or the number of fusions performed.  Conclusions: ALIF with anterior plate fixation achieved an adequate fusion rate with improvements in ODI and VAS scores meeting minimal clinically important difference thresholds. Postoperative disc space heights demonstrated significant improvements compared to preoperative measurements.

3.
Biomaterials ; 306: 122473, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38335719

RESUMO

Engineered matrices provide a valuable platform to understand the impact of biophysical factors on cellular behavior such as migration, proliferation, differentiation, and tissue remodeling, through mechanotransduction. While recent studies have identified some mechanisms of 3D mechanotransduction, there is still a critical knowledge gap in comprehending the interplay between 3D confinement, ECM properties, and cellular behavior. Specifically, the role of matrix stiffness in directing cellular fate in 3D microenvironment, independent of viscoelasticity, microstructure, and ligand density remains poorly understood. To address this gap, we designed a nanoparticle crosslinker to reinforce collagen-based hydrogels without altering their chemical composition, microstructure, viscoelasticity, and density of cell-adhesion ligand and utilized it to understand cellular dynamics. This crosslinking mechanism utilizes nanoparticles as crosslink epicenter, resulting in 10-fold increase in mechanical stiffness, without other changes. Human mesenchymal stem cells (hMSCs) encapsulated in 3D responded to mechanical stiffness by displaying circular morphology on soft hydrogels (5 kPa) and elongated morphology on stiff hydrogels (30 kPa). Stiff hydrogels facilitated the production and remodeling of nascent extracellular matrix (ECM) and activated mechanotransduction cascade. These changes were driven through intracellular PI3AKT signaling, regulation of epigenetic modifiers and activation of YAP/TAZ signaling. Overall, our study introduces a unique biomaterials platform to understand cell-ECM mechanotransduction in 3D for regenerative medicine as well as disease modelling.


Assuntos
Mecanotransdução Celular , Células-Tronco Mesenquimais , Humanos , Ligantes , Colágeno/química , Matriz Extracelular , Hidrogéis/química
4.
J Gastrointest Oncol ; 14(5): 2221-2228, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37969823

RESUMO

Background: Pancreatic ductal adenocarcinoma (PDAC) has a 5-year survival rate of approximately 10.7% in Australia. It is becoming an increasingly common cause of cancer mortality. The therapeutic model for PDAC remains limited, especially for those with metastatic disease on presentation. Methods: We completed a retrospective cohort study including all patients with PDAC presenting between April 2008 and October 2021 to St. John of God Subiaco Hospital in Western Australia. Overall survival (OS) was calculated via Kaplan-Meier method. Results: We identified 251 patients treated for PDAC. Of these, 134 patients (53%) had resectable, borderline resectable or locally advanced (LA) disease at diagnosis and 117 patients (47%) had metastatic disease. The median age of all patients was 66 years (range, 25-87 years). OS in PDAC was 26 months [95% confidence interval (CI): 23-30]. In the non-metastatic group OS was 34 months (95% CI: 30-39). In the metastatic group OS was 19 months (95% CI: 14-22). Treatment modalities varied between patients. Overall 123 patients were treated with chemotherapy alone, 55 patients had chemoradiotherapy, 34 patients had chemotherapy and surgery and 37 had tri-modality treatment including chemotherapy, surgery and radiotherapy. Two patients received cyberknife radiation alone. Conclusions: This retrospective study shows a significant prolonged survival for PDAC patients. Further studies are needed to validate second- and third-line regimens in PDAC.

5.
Am J Cardiol ; 207: 380-389, 2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37778227

RESUMO

Few studies have compared the clinical outcomes between valve-in-valve transcatheter aortic valve replacement (ViV-TAVR) with new-generation valves and re-operative surgical aortic valve replacement (Redo-SAVR). We compared the clinical outcomes of patients who underwent ViV-TAVR with those of patients who underwent Redo-SAVR at Cedars-Sinai Medical Center between 2015 and 2021. New-generation valves were used for ViV-TAVR. A propensity score-matched (PSM) analysis was performed to adjust for differences in baseline characteristics. The primary end point was all-cause mortality at 30 days and 2 years. In-hospital procedural and clinical outcomes were also compared between the groups. A total of 256 patients (140 who underwent ViV-TAVR and 116 who underwent Redo-SAVR) were eligible for PSM. In the unmatched cohort, patients in the ViV-TAVR group were older and had more co-morbidities than those in the Redo-SAVR group. After PSM, there were no significant differences in all-cause death between the ViV-TAVR and Redo-SAVR groups at 30 days (3.9% vs 2.6%, p = 0.65) or 2 years (6.5% vs 7.8%, p = 0.75). The incidences of stroke and heart failure rehospitalization were similar at 30 days and 2 years. The cumulative complication rates during hospitalization were significantly lower in the ViV-TAVR group than in the Redo-SAVR group (11.7% vs 28.6% p = 0.015). The long-term outcomes of ViV-TAVR using new-generation valves were similar to those of Redo-SAVR, although ViV-TAVR was associated with lower rates of in-hospital complications.


Assuntos
Estenose da Valva Aórtica , Bioprótese , Implante de Prótese de Valva Cardíaca , Próteses Valvulares Cardíacas , Substituição da Valva Aórtica Transcateter , Humanos , Implante de Prótese de Valva Cardíaca/efeitos adversos , Falha de Prótese , Reoperação , Resultado do Tratamento , Substituição da Valva Aórtica Transcateter/efeitos adversos , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/cirurgia , Estenose da Valva Aórtica/etiologia , Fatores de Risco
6.
Cureus ; 15(7): e41557, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37554601

RESUMO

Thromboembolism is a feared complication in plastic surgery and is linked to higher rates of morbidity and mortality. Despite extensive research, there is a lack of consistency between recommendations and clinical protocols to be implemented pre and post-surgery to reduce the incidence of thromboembolism. A systematic literature review was conducted using Pubmed and Scopus databases to determine the risk factors, screening methods, and existing treatment models for thromboembolism prevention. Articles in non-English languages were excluded. Analysis indicated that predominant risk factors include age (>35), elevated body mass index, coagulation disorders, smoking, estrogen therapies, genetic predisposition, vascular endothelium damage, stasis, and use of general anesthesia in patients with a history of cancer. Implementation of a proper prophylactic protocol is dependent on understanding the interplay between the aforementioned risk factors and the utilization of well-defined, evidence-based guidelines, such as the 2005 Caprini Risk Assessment Model and ultrasound surveillance. The literature review revealed that mechanical prophylaxis is the primary prevention method, followed by thromboprophylaxis for patients with higher Caprini scores. Plastic surgeons often underestimate the present risk stratification tools available for the prophylactic intervention of thromboembolism due to the fear of bleeding or hematoma complications postoperatively. In summary, this literature review emphasizes the importance of plastic surgeons selecting protocols that is inclusive of the patient's risk profile to yield a reduced risk of thromboembolism.

7.
Am J Surg ; 224(4): 1049-1056, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-34001333

RESUMO

BACKGROUND: Our objective is to evaluate the effect of distance to facility on the use of breast conservation therapy and reconstruction for early stage breast cancer. METHODS: Utilizing the National Cancer Database, we identified females, age <65, with Stage I invasive ductal carcinoma from 2004 to 2015. Using logistic regression, we compared radiation, mastectomy, and reconstruction treatment patterns. A subgroup analysis was performed within the mountain region (MR). RESULTS: Nationwide, there are decreasing odds of radiation, increasing odds of mastectomy, and increasing odds of reconstruction. Patients living farther were less likely to receive radiation, more likely to undergo mastectomy, with no effect on reconstruction. Within the MR, patients living farther from their facility were less likely to receive radiation, more likely to undergo mastectomy, however, they were less likely to undergo reconstruction. CONCLUSIONS: Nationwide and within the MR, patients living farther from their facility are less likely to receive radiation and more likely to undergo mastectomy. There is a disparity between the MR and the nation in use of reconstruction for this population.


Assuntos
Neoplasias da Mama , Carcinoma Ductal de Mama , Carcinoma Ductal , Mamoplastia , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Carcinoma Ductal/cirurgia , Carcinoma Ductal de Mama/cirurgia , Feminino , Humanos , Modelos Logísticos , Mastectomia , Mastectomia Segmentar
8.
Med J Aust ; 215(2): 89-93, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34218432

RESUMO

A patent foramen ovale (PFO) is an interatrial shunt, with a prevalence of 20-34% in the general population. While most people do not have secondary manifestations of a PFO, some reported sequelae include ischaemic stroke, migraine, platypnoea-orthodeoxia syndrome and decompression illness. Furthermore, in some cases, PFO closure should be considered for patients before neurosurgery and for patients with concomitant carcinoid syndrome. Recent trials support PFO closure for ischaemic stroke patients with high risk PFOs and absence of other identified stroke mechanisms. While PFOs can be associated with migraine with auras, with some patients reporting symptomatic improvement after closure, the evidence from randomised controlled trials is less clear in supporting the use of PFO closure for migraine treatment. PFO closure for other indications such as platypnoea-orthodeoxia syndrome, decompression illness and paradoxical embolism are based largely on case series with good clinical outcomes. PFO closure can be performed as a day surgical intervention with high procedural success and low risk of complications.


Assuntos
Cateterismo Cardíaco , Dispneia/etiologia , Forame Oval Patente/complicações , AVC Isquêmico/etiologia , Transtornos de Enxaqueca/etiologia , Dispneia/epidemiologia , Dispneia/cirurgia , Forame Oval Patente/epidemiologia , Forame Oval Patente/cirurgia , Humanos , AVC Isquêmico/epidemiologia , AVC Isquêmico/cirurgia , Transtornos de Enxaqueca/epidemiologia , Transtornos de Enxaqueca/cirurgia , Prevalência , Resultado do Tratamento
9.
Sleep Med Rev ; 58: 101491, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33962317

RESUMO

The aim of this systematic review was to investigate the effects of combined melatonin and bright light therapies on improved sleep and circadian outcomes. We conducted a systematic review that resulted in a total of eight papers meeting criteria. Four papers investigated the effectiveness of combined therapy in inducing a circadian phase shift on healthy participants. Combined therapy outperformed single light and melatonin therapies in phase advancing, but not in delaying, dim light melatonin onset (DLMO). The other four papers investigated the effect of combined therapy on sleep outcomes. Two of them were performed in elderly populations suffering from cognitive decline and two in delayed sleep-wake phase disorder (DSWPD) patients. While combined therapy was more beneficial than single therapy in elderly populations it did not show any benefit in DSWPD patients. The reported adverse effects of melatonin in elderly populations must be carefully considered. Future studies should investigate the separate and combined effect of melatonin and bright light on sleep and circadian outcomes in different target populations.


Assuntos
Melatonina , Transtornos do Sono do Ritmo Circadiano , Transtornos do Sono-Vigília , Idoso , Ritmo Circadiano , Humanos , Luz , Melatonina/uso terapêutico , Sono , Transtornos do Sono do Ritmo Circadiano/terapia
10.
Vasc Endovascular Surg ; 55(2): 105-111, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33063647

RESUMO

OBJECTIVES: The most widely accepted grading system for blunt traumatic aortic injury (BTAI) by the Society of Vascular Surgery (SVS) recommends endovascular repair for grade 2 and greater. Non-operative management in grade 2 injuries has been shown to be reasonable in certain circumstances. The natural history of low-grade injuries (1, 2) when managed non-operatively is not well defined. METHODS: Utilizing our trauma registry, patients from 2013 to 2016 with blunt traumatic injury who underwent initial computed tomography were identified. Aortic pathology was graded and grouped by SVS classification. Clinical courses were reviewed for timing of interventions, repeat imaging, concurrent injuries, and outcomes. Analysis of variance and Chi-square tests of significance were utilized to compare between groups. RESULTS: Out of 10,178 patients, we identified 32 with BTAI (grade: 1 (n = 13), 2 (n = 5), 3 (n = 3), 4 (n = 11)). High-grade injuries (3, 4) resulted only from motor vehicle, motorcycle, and pedestrian mechanisms. Initially, 9 patients (28%) required intervention, 5 (16%) were treated non-operatively, and 18 (56%) underwent repeat imaging. On repeat imaging, injuries that did not resolve remained stable and no injuries were found to progress. Of these patients, 9 (50%) required delayed intervention and 9 (50%) successfully underwent non-operative management. Patients with low-grade injuries were more likely to have successful non-operative management than those with high-grade injuries (72% vs 7%; p < 0.01). CONCLUSIONS: While low-grade injuries generally have good outcomes, some ultimately do require delayed intervention, and short-term imaging is not reliable in identifying these cases.


Assuntos
Aorta/cirurgia , Procedimentos Endovasculares , Centros de Traumatologia , Procedimentos Cirúrgicos Vasculares , Lesões do Sistema Vascular/terapia , Ferimentos não Penetrantes/terapia , Adolescente , Adulto , Aorta/diagnóstico por imagem , Aorta/lesões , Aortografia , Criança , Angiografia por Tomografia Computadorizada , Procedimentos Endovasculares/efeitos adversos , Feminino , Humanos , Escala de Gravidade do Ferimento , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Procedimentos Cirúrgicos Vasculares/efeitos adversos , Lesões do Sistema Vascular/diagnóstico por imagem , Ferimentos não Penetrantes/diagnóstico por imagem , Adulto Jovem
11.
Am J Surg ; 221(4): 737-740, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32354604

RESUMO

INTRODUCTION: Positron emission tomography computed tomography (PET-CT) is often used to stage nodal metastases in thin cutaneous melanoma, with limited evidence. METHODS: A retrospective review of patients with cutaneous malignant melanoma treated at our institution was performed from 2005 to 2015, identifying those who received a PET-CT prior to lymphadenectomy. Biopsy features, lymph node status, and PET-CT results were collected. We calculated the overall sensitivity, specificity, accuracy, likelihood ratios, and positive predictive value of PET-CT in identifying nodal metastases. Results were stratified by initial biopsy tumor depth. RESULTS: We identified 367 cases; 95 obtained a PET-CT prior to lymphadenectomy. Overall, sensitivity and specificity of PET-CT was 34.6% and 95.4%, respectively. The positive likelihood ratio and negative likelihood ratio were 7.62 and 0.68, respectively. The accuracy was 78.2%. The positive predictive value for T3 and T4 melanomas were 100% and 81.4%, respectively. For thin melanomas, specificity and accuracy was 88.2% and 88.2%, respectively. CONCLUSIONS: PET-CT has low specificity and its use alone is not recommended for initial staging of nodal metastases in thin cutaneous malignant melanoma.


Assuntos
Metástase Linfática/diagnóstico por imagem , Melanoma/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias Cutâneas/diagnóstico por imagem , Biópsia , Feminino , Fluordesoxiglucose F18 , Humanos , Masculino , Melanoma/patologia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Compostos Radiofarmacêuticos , Estudos Retrospectivos , Sensibilidade e Especificidade , Neoplasias Cutâneas/patologia , Melanoma Maligno Cutâneo
12.
World J Gastroenterol ; 26(30): 4428-4441, 2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32874055

RESUMO

BACKGROUND: Vedolizumab (VDZ), a humanised monoclonal antibody that selectively inhibits alpha4-beta7 integrins is approved for use in adult moderate to severe ulcerative colitis (UC) patients. AIM: To assess the efficacy and safety of VDZ in the real-world management of UC in a large multicenter cohort involving two countries and to identify predictors of achieving remission. METHODS: A retrospective review of Australian and Oxford, United Kingdom data for UC patients. Clinical response at 3 mo, endoscopic remission at 6 mo and clinical remission at 3, 6 and 12 mo were assessed. Cox regression models and Kaplan Meier curves were performed to assess the time to remission, time to failure and the covariates influencing them. Safety outcomes were recorded. RESULTS: Three hundred and three UC patients from 14 centres in Australia and United Kingdom, [60% n = 182, anti-TNF naïve] were included. The clinical response was 79% at 3 mo with more Australian patients achieving clinical response compared to Oxford (83% vs 70% P = 0.01). Clinical remission for all patients was 56%, 62% and 60% at 3, 6 and 12 mo respectively. Anti-TNF naive patients were more likely to achieve remission than exposed patients at all the time points (3 mo 66% vs 40% P < 0.001, 6 mo 73% vs 46% P < 0.001, 12 mo 66% vs 51% P = 0.03). More Australian patients achieved endoscopic remission at 6 mo compared to Oxford (69% vs 43% P = 0.01). On multi-variate analysis, anti-TNF naïve patients were 1.8 (95%CI: 1.3-2.3) times more likely to achieve remission than anti-TNF exposed (P < 0.001). 32 patients (11%) had colectomy by 12 mo. CONCLUSION: VDZ was safe and effective with 60% of UC patients achieving clinical remission at 12 mo and prior anti-TNF exposure influenced this outcome.


Assuntos
Colite Ulcerativa , Adulto , Anticorpos Monoclonais Humanizados , Austrália , Colite Ulcerativa/diagnóstico , Colite Ulcerativa/tratamento farmacológico , Fármacos Gastrointestinais/efeitos adversos , Humanos , Estudos Retrospectivos , Resultado do Tratamento , Fator de Necrose Tumoral alfa , Reino Unido
13.
Theranostics ; 10(15): 6977-6986, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32550916

RESUMO

Acute rejection (AR) remains a significant problem that negatively impacts long-term renal allograft survival. Numerous therapies are used to prevent AR that differ by center and recipient age. This variability confounds diagnostic methods. Methods: To develop an age-independent gene signature for AR effective across a broad array of immunosuppressive regimens, we compiled kidney transplant biopsy (n=1091) and peripheral blood (n=392) gene expression profiles from 12 independent public datasets. After removing genes differentially expressed in pediatric and adult patients, we compared gene expression profiles from biopsy and peripheral blood samples of patients with AR to those who were stable (STA), using Mann-Whitney U Tests with validation in independent testing datasets. We confirmed this signature in pediatric and adult patients (42 AR and 47 STA) from our institutional biorepository. Results: We identified a novel age-independent gene network that identified AR from both kidney and blood samples. We developed a 90-probe set signature targeting 76 genes that differentiated AR from STA and found an 8 gene subset (DIP2C, ENOSF1, FBXO21, KCTD6, PDXDC1, REXO2, HLA-E, and RAB31) that was associated with AR. Conclusion: We used publicly available datasets to create a gene signature of AR that identified AR irrespective of immunosuppression regimen or recipient age. This study highlights a novel model to screen and validate biomarkers across multiple treatment regimens.


Assuntos
Biomarcadores/sangue , Biologia Computacional/métodos , Rejeição de Enxerto/diagnóstico , Transplante de Rim/efeitos adversos , Transcriptoma , Transplante Homólogo/métodos , Adolescente , Adulto , Fatores Etários , Idoso , Biópsia , Criança , Pré-Escolar , Feminino , Rejeição de Enxerto/sangue , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/patologia , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Curva ROC , Adulto Jovem
14.
Am J Surg ; 220(4): 999-1003, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32252984

RESUMO

BACKGROUND: We aimed to determine the effects of preoperative carbohydrate-loading (CHO) as part of an enhanced recovery after surgery (ERAS) pathway on patients with/without type II diabetes (DMII). METHODS: Retrospective review of ERAS patients with CHO, including 80 with DMII, 275 without DMII in addition to 89 patients with DMII from the previous (non-ERAS) year. Outcomes included glucose-levels, insulin requirements, and complications. Logistic regression was used to determine the association of any complication with perioperative glucose control variables. RESULTS: Among ERAS versus non-ERAS patients with DMII, there were significant differences in median preoperative (142 mg/dL versus 129.5 mg/dL, p = 0.017) and postoperative day-1 glucose levels (152 mg/dL, versus 137.5 mg/dL, p = 0.004). There were no differences in insulin requirements, hypoglycemic episodes, or complications. Complications were not associated with Hgb-A1C%, home DMII-medications, or preoperative glucose measurement on logistic regression. CONCLUSIONS: Patients with DMII tolerated CHO without increasing insulin requirements or substantially affecting glucose levels or complications.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Tipo 2/complicações , Dieta da Carga de Carboidratos/métodos , Carboidratos da Dieta/administração & dosagem , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Recuperação Pós-Cirúrgica Melhorada , Cuidados Pré-Operatórios/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Diabetes Mellitus Tipo 2/sangue , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Período Pós-Operatório , Prognóstico , Estudos Retrospectivos , Estados Unidos/epidemiologia , Adulto Jovem
15.
Am J Surg ; 218(6): 1052-1059, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31619375

RESUMO

BACKGROUND: Our objective is to explore differences in survival and treatment approaches for hepatocellular carcinoma (HCC) between academic centers (ACs) and non-academic centers (NACs), which may contribute to disparities in the Mountain Region (MR). METHODS: Using the National Cancer Database, HCC cases from 2004 to 2015 in the MR were divided into AC and NAC subgroups. Cox-proportional hazard regression and binary logistic regression were performed to analyze survival, compare treatment patterns, and examine the effect of facility type and surgical approach on margin status. RESULTS: Treatment at ACs, compared to NACs, is associated with improved survival. At ACs, the odds of surgical or systemic treatment were higher. The odds of receiving radiation and positive margins was lower. Overall, the odds of positive margins was higher with laparoscopic compared to open or an unspecified surgical approach; this relationship persisted on subgroup analysis of NACs, but not ACs. CONCLUSIONS: Treatment of HCC at an AC in the MR increases the odds of surgery and improves survival. A laparoscopic approach increases the odds of positive margins, irrespective of center type.


Assuntos
Centros Médicos Acadêmicos , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/cirurgia , Padrões de Prática Médica/estatística & dados numéricos , Idoso , Feminino , Humanos , Laparoscopia , Transplante de Fígado , Masculino , Margens de Excisão , Pessoa de Meia-Idade , Taxa de Sobrevida , Estados Unidos
16.
ChemMedChem ; 7(9): 1580-6, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22807375

RESUMO

Microtubule stabilizers are powerful antimitotic compounds and represent a proven cancer treatment strategy. Several classes of compounds in clinical use or trials, such as the taxanes and epothilones, bind to the same region of ß-tubulin. Determining how these molecules interact with tubulin and stabilize microtubules is important both for understanding the mechanism of action and enhancing chemotherapeutic potential, for example, minimizing side effects, increasing solubility, and overcoming resistance. Structural studies using non-polymerized tubulin or stabilized polymers have produced different models of epothilone binding. In this study we used directed mutagenesis of the binding site on Saccharomyces cerevisiae ß-tubulin to analyze interactions between epothilone B and its biologically relevant substrate, dynamic microtubules. Five engineered amino acid changes contributed to a 125-fold increase in epothilone B cytotoxicity independent of inherent microtubule stability. The mutagenesis of endogenous ß-tubulin was done in otherwise isogenic strains. This facilitated the correlation of amino acid substitutions with altered cytotoxicity using molecular mechanics simulations. The results, which are based on the interaction between epothilone B and dynamic microtubules, most strongly support the binding mode determined by NMR spectroscopy-based studies. This work establishes a system for discriminating between potential binding modes and among various compounds and/or analogues using a sensitive biological activity-based readout.


Assuntos
Epotilonas/farmacologia , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Moduladores de Tubulina/farmacologia , Tubulina (Proteína)/metabolismo , Sequência de Aminoácidos , Sítios de Ligação , Humanos , Microtúbulos/química , Microtúbulos/genética , Microtúbulos/metabolismo , Modelos Moleculares , Mutagênese , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/efeitos dos fármacos , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Tubulina (Proteína)/química , Tubulina (Proteína)/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA