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2.
Ann Surg Oncol ; 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38898325

RESUMO

BACKGROUND: Retroperitoneal sarcomas (RPSs) present a surgical challenge, with complex anatomic relationships to organs and vascular structures. This pilot study investigated the role of three-dimensional (3D) augmented reality (3DAR) compared with standard imaging in preoperative planning and resection strategies. METHODS: For the study, 13 patients who underwent surgical resection of their RPS were selected based on the location of their tumor (right, left, pelvis). From the patients' preoperative computed tomography (CT) scans, 3DAR models were created using a D2P program and projected by an augmented-reality (AR) glass (Hololens). The 3DAR models were evaluated by three experienced sarcoma surgeons and compared with the baseline two-dimensional (2D) contrast-enhanced CT scans. RESULTS: Three members of the surgical team evaluated 13 models of retroperitoneal sarcomas, resulting in a total of 26 responses. When the surgical team was asked to evaluate whether the 3DAR better prepared the surgeon for planned surgical resection, 10 responses favored the 3DAR, 5 favored the 2D CT scans and 11 showed no difference (p = 0.074). According to 15 (57.6 %) of the 26 responses, the 3DAR offered additional value over standard imaging in the preoperative planning (median score of 4; range, 1-5). The median stated likelihood that the surgeons would consult the 3DAR was 5 (range, 2-5) for the preoperative setting and 3 (range, 1-5) for the intraoperative setting. CONCLUSIONS: This pilot study suggests that the use of 3DAR may provide additional value over current standard imaging in the preoperative planning for surgical resection of RPS, and the technology merits further study.

3.
Surg Oncol ; 52: 102017, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38091877

RESUMO

BACKGROUND: Pleomorphic dermal sarcoma (PDS) of the scalp is a rare tumour which is usually slow growing, but occasionally displays rapid growth and has a low rate of local recurrence. Surgical resection is the mainstay of treatment, with or without radiotherapy. The aim of this study is to describe the surgical approach and the additional benefit of radiotherapy to the treatment of these patients. METHODS: Retrospective, single-centre analysis of patients with PDS of the scalp that underwent surgical resection between 2007 and 2021 (n = 24). Treatment variables including depth of resection (superficial or deep to the galea aponeurotica) and adjuvant radiotherapy were investigated. RESULTS: Twenty-four patients were included in this study. Median age was 80 (range, 52-95), with a median ASA score of 3 (2-3). Sixteen (66.6 %) patients underwent surgical resection including the galea, while the rest (n = 8) did not or was not known. Radiotherapy was given in 7 (29 %) patients in which only 3 (12.5 %) were in the galeal resection group. Reasons for radiotherapy administration were concomitant SCC found at the same area of resection and close margins. In a median follow-up of was 26.2 months (range, 13.6-102.5) there was only one recurrence event. CONCLUSIONS: PDS of the scalp can be safely managed with a surgical resection if clear surgical margins are achieved without radiotherapy with good oncological outcomes.


Assuntos
Sarcoma , Neoplasias Cutâneas , Humanos , Idoso de 80 Anos ou mais , Sarcoma/cirurgia , Sarcoma/patologia , Estudos Retrospectivos , Couro Cabeludo/cirurgia , Couro Cabeludo/patologia , Neoplasias Cutâneas/cirurgia , Radioterapia Adjuvante , Recidiva Local de Neoplasia/cirurgia
4.
J Thromb Haemost ; 21(10): 2863-2872, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37331518

RESUMO

BACKGROUND: Despite high risk of venous thromboembolism (VTE) in patients with pancreatic cancer, there are little data on contact system activation in these patients. OBJECTIVES: To quantify contact system and intrinsic pathway activation and subsequent VTE risk in patients with pancreatic cancer. METHODS: Patients with advanced pancreatic cancer were compared with controls. Blood was drawn at baseline and patients were followed for 6 months. Complexes of proteases with their natural inhibitors, C1-esterase inhibitor (C1-INH), antithrombin (AT), or alpha-1 antitrypsin (α1at), were measured for complexes containing kallikrein (PKa:C1-INH), factor (F)XIIa (FXIIa:C1-INH), and FXIa (FXIa:C1-INH, FXIa:AT, FXIa:α1at). The association of cancer with complex levels was assessed in a linear regression model, adjusted for age, sex, and body mass index. In a competing risk regression model, we assessed associations between complex levels and VTE. RESULTS: One hundred nine patients with pancreatic cancer and 22 controls were included. The mean age was 66 years (SD, 8.4) in the cancer cohort and 52 years (SD, 10.1) in controls. In the cancer cohort, 18 (16.7%) patients developed VTE during follow-up. In the multivariable regression model, pancreatic cancer was associated with increased complexes of PKa:C1-INH (P < .001), FXIa:C1-INH (P < .001), and FXIa:AT (P < .001). High FXIa:α1at (subdistribution hazard ratio, 1.48 per log increase; 95% CI, 1.02-2.16) and FXIa:AT (subdistribution hazard ratio, 2.78 highest vs lower quartiles; 95% CI, 1.10-7.00) were associated with VTE. CONCLUSION: Complexes of proteases with their natural inhibitors were elevated in patients with cancer. These data suggest that the contact system and intrinsic pathway activation are increased in patients with pancreatic cancer.


Assuntos
Neoplasias Pancreáticas , Tromboembolia Venosa , Idoso , Feminino , Humanos , Masculino , Anticoagulantes , Antitrombina III , Endopeptidases , Calicreínas , Estudos Prospectivos , Tromboembolia Venosa/diagnóstico , Pessoa de Meia-Idade
6.
Blood ; 141(15): 1871-1883, 2023 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-36706361

RESUMO

A hypercoagulable state, chronic inflammation, and increased risk of venous thrombosis and stroke are prominent features in patients with sickle cell disease (SCD). Coagulation factor XII (FXII) triggers activation of the contact system that is known to be involved in both thrombosis and inflammation, but not in physiological hemostasis. Therefore, we investigated whether FXII contributes to the prothrombotic and inflammatory complications associated with SCD. We found that when compared with healthy controls, patients with SCD exhibit increased circulating biomarkers of FXII activation that are associated with increased activation of the contact pathway. We also found that FXII, but not tissue factor, contributes to enhanced thrombin generation and systemic inflammation observed in sickle cell mice challenged with tumor necrosis factor α. In addition, FXII inhibition significantly reduced experimental venous thrombosis, congestion, and microvascular stasis in a mouse model of SCD. Moreover, inhibition of FXII attenuated brain damage and reduced neutrophil adhesion to the brain vasculature of sickle cell mice after ischemia/reperfusion induced by transient middle cerebral artery occlusion. Finally, we found higher FXII, urokinase plasminogen activator receptor, and αMß2 integrin expression in neutrophils of patients with SCD compared with healthy controls. Our data indicate that targeting FXII effectively reduces experimental thromboinflammation and vascular complications in a mouse model of SCD, suggesting that FXII inhibition may provide a safe approach for interference with inflammation, thrombotic complications, and vaso-occlusion in patients with SCD.


Assuntos
Anemia Falciforme , Fator XII , Animais , Camundongos , Anemia Falciforme/complicações , Anemia Falciforme/metabolismo , Fator XII/metabolismo , Inflamação , Acidente Vascular Cerebral , Trombose/metabolismo
7.
Implement Sci Commun ; 3(1): 103, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36183121

RESUMO

BACKGROUND: Sentinel node biopsy (SN biopsy) is a surgical procedure used to accurately stage patients with primary melanoma at high risk of recurrence. Although Australian Melanoma Management Guidelines recommend SN biopsy be considered in patients with melanomas > 1 mm thick, SN biopsy rates in Australia are reportedly low. Our objective was to identify factors impacting the acceptance, adoption and adherence to the Australian SN biopsy guideline recommendations. METHODS: Opinions of Australian key informants including clinicians, representatives from melanoma education and training providers, professional associations and colleges, and melanoma advocacy organisations were collected through semi-structured interviews (n = 29) and from publicly released statements (n = 14 news articles). Data analysis involved inductive and deductive thematic analysis using Flottorp's determinants framework. RESULTS: A complex interplay of contemporary and historical factors was identified as influencing acceptance, adoption and adherence to the SN biopsy guideline recommendations at the individual, guideline, patient, organisational and social levels. Expert and peer opinion leaders have played an important role in facilitating or inhibiting adoption of guideline recommendations, as have financial incentives driven by healthcare-funding policies and non-financial incentives including professional identity and standing. Of critical importance have been the social and knowledge boundaries that exist between different professional groups to whom the guidelines apply (surgeons, dermatologists and primary care practitioners) with adherence to the guideline recommendations having the potential to shift work across professional boundaries, altering a clinician's workflow and revenue. More recently, the emergence of effective immunotherapies and targeted therapies for patients at high risk of recurrence, the emergence of new opinion leaders on the topic (in medical oncology), and patient demands for accurate staging are playing crucial roles in overcoming the resistance to change created by these social and knowledge boundaries. CONCLUSIONS: Acceptance and adherence to SN biopsy guideline recommendations in Australia over the past 20 years has involved a process of renegotiation and reframing of the evidence for SN biopsy in melanoma by clinicians from different professional groups and networks. This process has helped to refine the evidence for SN biopsy and our understanding of appropriate adoption. New effective systemic therapies have changed the balance towards accepting guideline recommendations.

8.
JAMA Surg ; 157(9): 835-842, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35921122

RESUMO

Importance: Sentinel lymph node (SLN) biopsy is a standard staging procedure for cutaneous melanoma. Regional disease control is a clinically important therapeutic goal of surgical intervention, including nodal surgery. Objective: To determine how frequently SLN biopsy without completion lymph node dissection (CLND) results in long-term regional nodal disease control in patients with SLN metastases. Design, Setting, and Participants: The second Multicenter Selective Lymphadenectomy Trial (MSLT-II), a prospective multicenter randomized clinical trial, randomized participants with SLN metastases to either CLND or nodal observation. The current analysis examines observation patients with regard to regional nodal recurrence. Trial patients were aged 18 to 75 years with melanoma metastatic to SLN(s). Data were collected from December 2004 to April 2019, and data were analyzed from July 2020 to January 2022. Interventions: Nodal observation with ultrasonography rather than CLND. Main Outcomes and Measures: In-basin nodal recurrence. Results: Of 823 included patients, 479 (58.2%) were male, and the mean (SD) age was 52.8 (13.8) years. Among 855 observed basins, at 10 years, 80.2% (actuarial; 95% CI, 77-83) of basins were free of nodal recurrence. By univariable analysis, freedom from regional nodal recurrence was associated with age younger than 50 years (hazard ratio [HR], 0.49; 95% CI, 0.34-0.70; P < .001), nonulcerated melanoma (HR, 0.36; 95% CI, 0.36-0.49; P < .001), thinner primary melanoma (less than 1.5 mm; HR, 0.46; 95% CI, 0.27-0.78; P = .004), axillary basin (HR, 0.61; 95% CI, 0.44-0.86; P = .005), fewer positive SLNs (1 vs 3 or more; HR, 0.32; 95% CI, 0.14-0.75; P = .008), and SLN tumor burden (measured by diameter less than 1 mm [HR, 0.39; 95% CI, 0.26-0.60; P = .001] or less than 5% area [HR, 0.36; 95% CI, 0.24-0.54; P < .001]). By multivariable analysis, younger age (HR, 0.57; 95% CI, 0.39-0.84; P = .004), thinner primary melanoma (HR, 0.40; 95% CI, 0.22-0.70; P = .002), axillary basin (HR, 0.55; 95% CI, 0.31-0.96; P = .03), SLN metastasis diameter less than 1 mm (HR, 0.52; 95% CI, 0.33-0.81; P = .007), and area less than 5% (HR, 0.58; 95% CI, 0.38-0.88; P = .01) were associated with basin control. When looking at the identified risk factors of age (50 years or older), ulceration, Breslow thickness greater than 3.5 mm, nonaxillary basin, and tumor burden of maximum diameter of 1 mm or greater and/or metastasis area of 5% or greater and excluding missing value cases, basin disease-free rates at 5 years were 96% (95% CI, 88-100) for patients with 0 risk factors, 89% (95% CI, 82-96) for 1 risk factor, 86% (95% CI, 80-93) for 2 risk factors, 80% (95% CI, 71-89) for 3 risk factors, 61% (95% CI, 48-74) for 4 risk factors, and 54% (95% CI, 36-72) for 5 or 6 risk factors. Conclusions and Relevance: This randomized clinical trial was the largest prospective evaluation of long-term regional basin control in patients with melanoma who had nodal observation after removal of a positive SLN. SLN biopsy without CLND cleared disease in the affected nodal basin in most patients, even those with multiple risk factors for in-basin recurrence. In addition to its well-validated value in staging, SLN biopsy may also be regarded as therapeutic in some patients. Trial Registration: ClinicalTrials.gov Identifier: NCT00297895.


Assuntos
Melanoma , Neoplasias Cutâneas , Feminino , Humanos , Excisão de Linfonodo , Metástase Linfática , Masculino , Melanoma/patologia , Prognóstico , Biópsia de Linfonodo Sentinela/métodos , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/cirurgia
10.
Br J Haematol ; 197(3): 320-325, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35286715

RESUMO

With new, effective treatments for chronic lymphocytic leukaemia (CLL) the impact of second malignancies is increasingly important. We performed a retrospective case-controlled study examining the effect of CLL and its treatment on melanoma-specific survival and recurrence. A total of 56 patients with melanoma with CLL were matched 1:1 to patients without CLL for age, date of diagnosis, gender and melanoma tumour, node, metastasis (TNM) stage. Multivariate analysis found CLL was associated with significantly worse melanoma-specific mortality (hazard ratio [HR] 2.46, 95% confidence interval [CI] 1.27-4.74, p = 0.007) and recurrence (HR 3.44, 95% CI 1.79-6.63, p < 0.001). Patients with CLL had poor immunotherapy tolerance and prior CLL treatment was not associated with melanoma outcomes.


Assuntos
Leucemia Linfocítica Crônica de Células B , Melanoma , Segunda Neoplasia Primária , Estudos de Casos e Controles , Humanos , Melanoma/terapia , Estudos Retrospectivos
11.
Pathology ; 54(1): 6-19, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34937664

RESUMO

Targeted therapy (BRAF inhibitor plus MEK inhibitor) is now among the possible treatment options for patients with BRAF mutation-positive stage III or stage IV melanoma. This makes prompt BRAF mutation testing an important step in the management of patients diagnosed with stage III or IV melanoma; one that can help better ensure that the optimal choice of systemic treatment is initiated with minimal delay. This article offers guidance about when and how BRAF mutation testing should be conducted when patients are diagnosed with melanoma in Australia. Notably, it recommends that pathologists reflexively order BRAF mutation testing whenever a patient is found to have American Joint Committee on Cancer (AJCC)/Union for International Cancer Control (UICC) stage III or IV melanoma (i.e., any metastatic spread beyond the primary tumour) and that patient's BRAF mutation status is hitherto unknown, even if BRAF mutation testing has not been specifically requested by the treating clinician (in Australia, Medicare-subsidised BRAFV600 mutation testing does not need to be requested by the treating clinician). When performed in centres with appropriate expertise and experience, immunohistochemistry (IHC) using the anti-BRAF V600E monoclonal antibody (VE1) can be a highly sensitive and specific means of detecting BRAFV600E mutations, and may be used as a rapid and relatively inexpensive initial screening test. However, VE1 immunostaining can be technically challenging and difficult to interpret, particularly in heavily pigmented tumours; melanomas with weak, moderate or focal BRAFV600E immunostaining should be regarded as equivocal. It must also be remembered that other activating BRAFV600 mutations (including BRAFV600K), which account for ∼10-20% of BRAFV600 mutations, are not detected with currently available IHC antibodies. For these reasons, if available and practicable, we recommend that DNA-based BRAF mutation testing always be performed, regardless of whether IHC-based testing is also conducted. Advice about tissue/specimen selection for BRAF mutation testing of patients diagnosed with stage III or IV melanoma is also offered in this article; and potential pitfalls when interpreting BRAF mutation tests are highlighted.


Assuntos
Melanoma , Proteínas Proto-Oncogênicas B-raf/genética , Austrália , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Análise Mutacional de DNA , Guias como Assunto , Humanos , Imuno-Histoquímica/métodos , Melanoma/diagnóstico , Melanoma/patologia , Melanoma/terapia , Terapia de Alvo Molecular , Mutação , Programas Nacionais de Saúde , Estadiamento de Neoplasias , Proteínas Proto-Oncogênicas B-raf/metabolismo , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/terapia
13.
Australas J Dermatol ; 63(1): 43-52, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34751431

RESUMO

PURPOSE: This study examined the clinical outcomes and prognostic factors of patients with metastatic cutaneous SCC metastatic to the axilla and groin when managed with curative-intent lymphadenectomy and received (neo)adjuvant treatment. METHODS AND MATERIALS: We conducted a single institution retrospective review. Patients who had nodal disease without distant spread were 18 years or older with no non-cutaneous primary identified. RESULTS: From January 2000 to July 2015, 78 patients were treated for axilla (64, 82%) or inguinal (14, 18%) involvement with cSCC. The median age was 75.5 years (range: 29-95), and 8 patients (11%) were immunosuppressed. The median size of the largest node was 45 mm (range: 8-135), and extracapsular extension was found in 63 (81%) cases. A majority of patients were treated with surgery alone (21, 26.9%) and surgery with adjuvant radiation therapy (54, 69%). The 2-year OS and PFS were 50% (95% CI: 40%-63%) and 43% (95% CI: 33%-56%), and 5-year OS and PFS were 33% (95% CI:23%-47%) and 32% (95% CI:22%-46%) respectively in the entire cohort. On univariable analysis, factors associated with longer OS were as follows: younger age (HR 1.1, 95% CI: 0.9-1.3 P = 0.021), improved performance status (HR 1.5, 95% CI:1.0-2.3 P = 0.026), lack of immunosuppression (HR 3.3, 95% CI: 1.5-7.3 P = 0.001), lower lymph node ratio (HR 1.2, 95% CI:1.0-1.3 P = 0.007), lower number of positive nodes (HR 1.1, 95% CI:1.0-1.2 P = 0.004) and the use of radiation therapy (HR 0.5, 95% CI:0.3-0.9 P = 0.012). CONCLUSION: Metastasis to the axilla and groin with cSCC has poor outcomes with standard treatment. The addition of immunotherapy warrants investigation.


Assuntos
Carcinoma de Células Escamosas/secundário , Metástase Linfática , Neoplasias Cutâneas/patologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Axila/patologia , Axila/cirurgia , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/terapia , Feminino , Virilha/patologia , Virilha/cirurgia , Humanos , Hospedeiro Imunocomprometido , Excisão de Linfonodo , Masculino , Pessoa de Meia-Idade , Intervalo Livre de Progressão , Radioterapia Adjuvante , Estudos Retrospectivos , Neoplasias Cutâneas/mortalidade , Neoplasias Cutâneas/terapia
14.
J Surg Oncol ; 124(8): 1544-1550, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34406652

RESUMO

BACKGROUND: The evidence-based management of melanoma patients with a positive sentinel lymph node biopsy (SLNB) has undergone a dramatic shift following publication of practice-changing surgical trials demonstrating no melanoma-specific survival advantage for completion lymph node dissection (CLND) in this scenario. We aimed to survey how surgeons' clinical practice had shifted in response to new evidence from these trials, and at a time when there was starting to become available systemic adjuvant treatments for AJCC Stage III melanoma patients. METHODS: A web-based survey consisting of practice-based questions and hypothetical clinical scenarios about current melanoma practice with regard to positive sentinel node biopsy was developed and sent to the surgical members of a Melanoma and Skin Cancer (MASC) Trials group in December 2018. Responses were analysed using descriptive statistics. RESULTS: There were 212 invitations sent and 65 respondents (31%). Respondents were from 17 countries, 94% of whom practice in specialist melanoma centres or at referral centres. Of these 97% were familiar with the MSLT2 and DeCOG-SLT clinical trials. At survey, 5% of respondents reported routinely recommending CLND and 55% recommend CLND in selected cases. Respondents were most likely to recommend CLND when multiple SLNs were positive. Important factors for surgical decision-making mentioned included size of SLN deposit, number of positive SLNs and likely compliance with the recommended surveillance regimen. CONCLUSION: In line with rapid adoption of published evidence, surgical management of Stage III melanoma has altered significantly, with few surgeons within the cohort now performing routine CLNDs after positive SLNB.


Assuntos
Excisão de Linfonodo/métodos , Melanoma/cirurgia , Biópsia de Linfonodo Sentinela/métodos , Linfonodo Sentinela/cirurgia , Cirurgiões/estatística & dados numéricos , Adulto , Idoso , Ensaios Clínicos como Assunto , Gerenciamento Clínico , Feminino , Humanos , Masculino , Melanoma/patologia , Pessoa de Meia-Idade , Prognóstico , Linfonodo Sentinela/patologia , Inquéritos e Questionários
15.
Cells ; 10(6)2021 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-34204869

RESUMO

Human adipose-derived stromal/stem cells (hASC) are widely used for in vitro modeling of physiologically relevant human adipose tissue. These models are useful for the development of tissue constructs for soft tissue regeneration and 3-dimensional (3D) microphysiological systems (MPS) for drug discovery. In this systematic review, we report on the current state of hASC culture and assessment methods for adipose tissue engineering using 3D MPS. Our search efforts resulted in the identification of 184 independent records, of which 27 were determined to be most relevant to the goals of the present review. Our results demonstrate a lack of consensus on methods for hASC culture and assessment for the production of physiologically relevant in vitro models of human adipose tissue. Few studies have assessed the impact of different 3D culture conditions on hASC adipogenesis. Additionally, there has been a limited use of assays for characterizing the functionality of adipose tissue in vitro. Results from this study suggest the need for more standardized culture methods and further analysis on in vitro tissue functionality. These will be necessary to validate the utility of 3D MPS as an in vitro model to reduce, refine, and replace in vivo experiments in the drug discovery regulatory process.


Assuntos
Adipogenia , Tecido Adiposo/metabolismo , Técnicas de Cultura de Células , Células-Tronco Mesenquimais/metabolismo , Modelos Biológicos , Engenharia Tecidual , Tecido Adiposo/citologia , Humanos , Células-Tronco Mesenquimais/citologia
16.
Blood ; 138(3): 259-272, 2021 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-33827130

RESUMO

Acetaminophen (APAP)-induced liver injury is associated with activation of coagulation and fibrinolysis. In mice, both tissue factor-dependent thrombin generation and plasmin activity have been shown to promote liver injury after APAP overdose. However, the contribution of the contact and intrinsic coagulation pathways has not been investigated in this model. Mice deficient in individual factors of the contact (factor XII [FXII] and prekallikrein) or intrinsic coagulation (FXI) pathway were administered a hepatotoxic dose of 400 mg/kg of APAP. Neither FXII, FXI, nor prekallikrein deficiency mitigated coagulation activation or hepatocellular injury. Interestingly, despite the lack of significant changes to APAP-induced coagulation activation, markers of liver injury and inflammation were significantly reduced in APAP-challenged high-molecular-weight kininogen-deficient (HK-/-) mice. Protective effects of HK deficiency were not reproduced by inhibition of bradykinin-mediated signaling, whereas reconstitution of circulating levels of HK in HK-/- mice restored hepatotoxicity. Fibrinolysis activation was observed in mice after APAP administration. Western blotting, enzyme-linked immunosorbent assay, and mass spectrometry analysis showed that plasmin efficiently cleaves HK into multiple fragments in buffer or plasma. Importantly, plasminogen deficiency attenuated APAP-induced liver injury and prevented HK cleavage in the injured liver. Finally, enhanced plasmin generation and HK cleavage, in the absence of contact pathway activation, were observed in plasma of patients with acute liver failure due to APAP overdose. In summary, extrinsic but not intrinsic pathway activation drives the thromboinflammatory pathology associated with APAP-induced liver injury in mice. Furthermore, plasmin-mediated cleavage of HK contributes to hepatotoxicity in APAP-challenged mice independently of thrombin generation or bradykinin signaling.


Assuntos
Acetaminofen/efeitos adversos , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Fibrinolisina/metabolismo , Fibrinólise/efeitos dos fármacos , Cininogênios/metabolismo , Proteólise/efeitos dos fármacos , Acetaminofen/farmacologia , Animais , Doença Hepática Induzida por Substâncias e Drogas/genética , Doença Hepática Induzida por Substâncias e Drogas/patologia , Fator XII/genética , Fator XII/metabolismo , Feminino , Fibrinolisina/genética , Humanos , Cininogênios/genética , Masculino , Camundongos , Camundongos Knockout , Pré-Calicreína/genética , Pré-Calicreína/metabolismo
17.
Tissue Eng Part A ; 27(7-8): 479-488, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33528293

RESUMO

International regulatory agencies such as the Food and Drug Administration have mandated that the scientific community develop humanized microphysiological systems (MPS) as an in vitro alternative to animal models in the near future. While the breast cancer research community has long appreciated the importance of three-dimensional growth dynamics in their experimental models, there are remaining obstacles preventing a full conversion to humanized MPS for drug discovery and pathophysiological studies. This perspective evaluates the current status of human tissue-derived cells and scaffolds as building blocks for an "idealized" breast cancer MPS based on bioengineering design principles. It considers the utility of adipose tissue as a potential source of endothelial, lymphohematopoietic, and stromal cells for the support of breast cancer epithelial cells. The relative merits of potential MPS scaffolds derived from adipose tissue, blood components, and synthetic biomaterials is evaluated relative to the current "gold standard" material, Matrigel, a murine chondrosarcoma-derived basement membrane-enriched hydrogel. The advantages and limitations of a humanized breast cancer MPS are discussed in the context of in-process and destructive read-out assays. Impact statement Regulatory authorities have highlighted microphysiological systems as an emerging tool in breast cancer research. This has been led by calls for more predictive human models and reduced animal experimentation. This perspective describes how human-derived cells, extracellular matrices, and hydrogels will provide the building blocks to create breast cancer models that accurately reflect diversity at multiple levels, that is, patient ethnicity, pathophysiology, and metabolic status.


Assuntos
Neoplasias da Mama , Animais , Bioengenharia , Feminino , Humanos , Camundongos , Estados Unidos
18.
Biomater Transl ; 2(4): 301-306, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35837416

RESUMO

Microphysiological systems (MPS) created with human-derived cells and biomaterial scaffolds offer a potential in vitro alternative to in vivo animal models. The adoption of three-dimensional MPS models has economic, ethical, regulatory, and scientific implications for the fields of regenerative medicine, metabolism/obesity, oncology, and pharmaceutical drug discovery. Key opinion leaders acknowledge that MPS tools are uniquely positioned to aid in the objective to reduce, refine, and eventually replace animal experimentation while improving the accuracy of the finding's clinical translation. Adipose tissue has proven to be an accessible and available source of human-derived stromal vascular fraction (SVF) cells, a heterogeneous population available at point of care, and adipose-derived stromal/stem cells, a relatively homogeneous population requiring plastic adherence and culture expansion of the SVF cells. The adipose-derived stromal/stem cells or SVF cells, in combination with human tissue or synthetic biomaterial scaffolds, can be maintained for extended culture periods as three-dimensional MPS models under angiogenic, stromal, adipogenic, or osteogenic conditions. This review highlights recent literature relating to the versatile use of adipose-derived cells as fundamental components of three-dimensional MPS models for discovery research and development. In this context, it compares the merits and limitations of the adipose-derived stromal/stem cells relative to SVF cell models and considers the likely directions that this emerging field of scientific discovery will take in the near future.

19.
J Surg Oncol ; 123(1): 117-126, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33084061

RESUMO

BACKGROUND AND OBJECTIVES: Limited literature exists examining the immune microenvironment in liposarcoma, particularly with regard to the impact of radiotherapy. A major problem is the lack of scoring system for the tumour-infiltrating lymphocytes (TILs) in sarcoma. This study aims to describe the immune environment pre- and postradiotherapy and identify the optimal immune infiltrate scoring system for sarcoma. METHODS: Thirty-nine paired tissue samples (pre- and postradiotherapy) from patients with liposarcoma were scored by two pathologists for TILs using pre-existing systems (for breast cancer and melanoma) and compared for interobserver reliability. Immunohistochemical staining was performed for various immune markers. RESULTS: The TIL scoring system for breast cancer yielded perfect agreement (κ = 1.000). 21% of patients had increased TILs after radiotherapy, 87.5% of whom had dedifferentiated liposarcoma. Immune suppressor expression was increased frequently after radiotherapy (CD68 increased in 59.4%, PD-L1 increased in 25%). Immune effector expression (CD8) was unchanged in 84.4%. CONCLUSIONS: Breast cancer TIL scoring is reproducible in liposarcoma and has high interobserver reliability. Radiotherapy was observed to have a limited impact on immune effectors but seemed to have more impact in upregulating immune suppressors, suggesting radiotherapy may contribute to disease control through immunomodulatory effects. Dedifferentiated liposarcoma represents a uniquely responsive subtype.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Lipossarcoma/imunologia , Linfócitos do Interstício Tumoral/imunologia , Recidiva Local de Neoplasia/imunologia , Radioterapia/métodos , Microambiente Tumoral/imunologia , Adolescente , Adulto , Idoso , Linfócitos T CD8-Positivos/efeitos da radiação , Feminino , Seguimentos , Humanos , Lipossarcoma/patologia , Lipossarcoma/radioterapia , Linfócitos do Interstício Tumoral/efeitos da radiação , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/radioterapia , Prognóstico , Estudos Retrospectivos , Microambiente Tumoral/efeitos da radiação , Adulto Jovem
20.
Sci Adv ; 6(47)2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33208364

RESUMO

Cystic fibrosis (CF) results from mutations in the chloride-conducting CF transmembrane conductance regulator (CFTR) gene. Airway dehydration and impaired mucociliary clearance in CF is proposed to result in tonic epithelial sodium channel (ENaC) activity, which drives amiloride-sensitive electrogenic sodium absorption. Decreasing sodium absorption by inhibiting ENaC can reverse airway surface liquid dehydration. Here, we inhibit endogenous heterotrimeric ENaC channels by introducing inactivating mutant ENaC α mRNA (αmutENaC). Lipid nanoparticles carrying αmutENaC were transfected in CF-based airway cells in vitro and in vivo. We observed a significant decrease in macroscopic as well as amiloride-sensitive ENaC currents and an increase in airway surface liquid height in CF airway cells. Similarly, intranasal transfection of αmutENaC mRNA decreased amiloride-sensitive nasal potential difference in CFTRKO mice. These data suggest that mRNA-based ENaC inhibition is a powerful strategy for reducing mucus dehydration and has therapeutic potential for treating CF in all patients, independent of genotype.


Assuntos
Fibrose Cística , Amilorida/farmacologia , Amilorida/uso terapêutico , Animais , Fibrose Cística/genética , Fibrose Cística/terapia , Desidratação , Canais Epiteliais de Sódio/genética , Canais Epiteliais de Sódio/metabolismo , Humanos , Lipossomos , Camundongos , Nanopartículas , RNA Mensageiro/genética , Sódio/metabolismo
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