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1.
J Hepatol ; 80(6): 892-903, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38458319

RESUMEN

BACKGROUND & AIMS: Cholangiocarcinoma (CCA) is a poorly immunogenic malignancy associated with limited survival. Syngeneic immunocompetent mouse models of CCA are an essential tool to elucidate the tumor immune microenvironment (TIME), understand mechanisms of tumor immune evasion, and test novel immunotherapeutic strategies. The scope of this study was to develop and characterize immunocompetent CCA models with distinct genetic drivers, and correlate tumor genomics, immunobiology, and therapeutic response. METHODS: A multifaceted approach including scRNA-seq, CITE-seq, whole exome and bulk RNA sequencing was employed. FDA-approved PD-1/PD-L1 antibodies were tested in humanized PD-1/PD-L1 mice (HuPD-H1). RESULTS: A genetic mouse model of intrahepatic CCA (iCCA) driven by intrabiliary transduction of Fbxw7ΔF/Akt that mimics human iCCA was generated. From the Fbxw7ΔF/Akt tumors, a murine cell line (FAC) and syngeneic model with genetic and phenotypic characteristics of human iCCA were developed. Established SB1 (YAPS127A/Akt) and KPPC (KrasG12Dp53L/L) models were compared to the FAC model. Although the models had transcriptomic similarities, they had substantial differences as well. Mutation patterns of FAC, SB1, and KPPC cells matched different mutational signatures in Western and Japanese CCA patient cohorts. KPPC tumors had a high tumor mutation burden. FAC tumors had a T cell-infiltrated TIME, while SB1 tumors had a preponderance of suppressive myeloid cells. FAC, SB1, and KPPC tumors matched different immune signatures in human iCCA cohorts. Moreover, FAC, SB1, and KPPC tumor-bearing HuPD-H1 mice displayed differential responses to nivolumab or durvalumab. CONCLUSIONS: Syngeneic iCCA models display a correlation between tumor genotype and TIME phenotype, with differential responses to FDA-approved immunotherapies. This study underscores the importance of leveraging multiple preclinical models to understand responses to immunotherapy in different genetic subsets of human CCA. IMPACT AND IMPLICATIONS: Understanding the relationship between tumor genotype and the phenotype of the immune microenvironment is an unmet need in cholangiocarcinoma (CCA). Herein, we use syngeneic murine models of intrahepatic CCA with different genetic drivers to demonstrate a correlation between tumor genotype and immune microenvironment phenotype in murine models, which is associated with differential responses to FDA-approved immunotherapies. This information will help guide other preclinical studies. Additionally, it emphasizes that immune checkpoint inhibition in patients with CCA is not a "one-size-fits-all" approach. Our observations suggest that, as for targeted therapies, patients should be stratified and selected for treatment according to their tumor genetics.


Asunto(s)
Neoplasias de los Conductos Biliares , Colangiocarcinoma , Modelos Animales de Enfermedad , Microambiente Tumoral , Animales , Colangiocarcinoma/inmunología , Colangiocarcinoma/genética , Ratones , Microambiente Tumoral/inmunología , Humanos , Neoplasias de los Conductos Biliares/inmunología , Neoplasias de los Conductos Biliares/genética , Proteína 7 que Contiene Repeticiones F-Box-WD/genética , Línea Celular Tumoral
2.
J Hepatol ; 81(1): 120-134, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38428643

RESUMEN

BACKGROUND & AIMS: The PTEN-AKT pathway is frequently altered in extrahepatic cholangiocarcinoma (eCCA). We aimed to evaluate the role of PTEN in the pathogenesis of eCCA and identify novel therapeutic targets for this disease. METHODS: The Pten gene was genetically deleted using the Cre-loxp system in biliary epithelial cells. The pathologies were evaluated both macroscopically and histologically. The characteristics were further analyzed by immunohistochemistry, reverse-transcription PCR, cell culture, and RNA sequencing. Some features were compared to those in human eCCA samples. Further mechanistic studies utilized the conditional knockout of Trp53 and Aurora kinase A (Aurka) genes. We also tested the effectiveness of an Aurka inhibitor. RESULTS: We observed that genetic deletion of the Pten gene in the extrahepatic biliary epithelium and peri-ductal glands initiated sclerosing cholangitis-like lesions in mice, resulting in enlarged and distorted extrahepatic bile ducts in mice as early as 1 month after birth. Histologically, these lesions exhibited increased epithelial proliferation, inflammatory cell infiltration, and fibrosis. With aging, the lesions progressed from low-grade dysplasia to invasive carcinoma. Trp53 inactivation further accelerated disease progression, potentially by downregulating senescence. Further mechanistic studies showed that both human and mouse eCCA showed high expression of AURKA. Notably, the genetic deletion of Aurka completely eliminated Pten deficiency-induced extrahepatic bile duct lesions. Furthermore, pharmacological inhibition of Aurka alleviated disease progression. CONCLUSIONS: Pten deficiency in extrahepatic cholangiocytes and peribiliary glands led to a cholangitis-to-cholangiocarcinoma continuum that was dependent on Aurka. These findings offer new insights into preventive and therapeutic interventions for extrahepatic CCA. IMPACT AND IMPLICATIONS: The aberrant PTEN-PI3K-AKT signaling pathway is commonly observed in human extrahepatic cholangiocarcinoma (eCCA), a disease with a poor prognosis. In our study, we developed a mouse model mimicking cholangitis to eCCA progression by conditionally deleting the Pten gene via Pdx1-Cre in epithelial cells and peribiliary glands of the extrahepatic biliary duct. The conditional Pten deletion in these cells led to cholangitis, which gradually advanced to dysplasia, ultimately resulting in eCCA. The loss of Pten heightened Akt signaling, cell proliferation, inflammation, fibrosis, DNA damage, epigenetic signaling, epithelial-mesenchymal transition, cell dysplasia, and cellular senescence. Genetic deletion or pharmacological inhibition of Aurka successfully halted disease progression. This model will be valuable for testing novel therapies and unraveling the mechanisms of eCCA tumorigenesis.


Asunto(s)
Aurora Quinasa A , Neoplasias de los Conductos Biliares , Colangiocarcinoma , Fosfohidrolasa PTEN , Fosfohidrolasa PTEN/genética , Fosfohidrolasa PTEN/metabolismo , Animales , Aurora Quinasa A/genética , Aurora Quinasa A/metabolismo , Colangiocarcinoma/etiología , Colangiocarcinoma/patología , Colangiocarcinoma/genética , Colangiocarcinoma/metabolismo , Ratones , Neoplasias de los Conductos Biliares/patología , Neoplasias de los Conductos Biliares/genética , Neoplasias de los Conductos Biliares/etiología , Neoplasias de los Conductos Biliares/metabolismo , Humanos , Ratones Noqueados , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Conductos Biliares Extrahepáticos/patología , Modelos Animales de Enfermedad , Colangitis/patología , Colangitis/etiología , Colangitis/metabolismo , Colangitis/genética , Transducción de Señal
3.
Hepatology ; 77(3): 760-773, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36152015

RESUMEN

BACKGROUND AND AIMS: This study aimed to investigate safety and efficacy of silmitasertib, an oral small molecule casein kinase 2 inhibitor, plus gemcitabine and cisplatin (G+C) versus G+C in locally advanced/metastatic cholangiocarcinoma. APPROACH AND RESULTS: This work is a Phase 1b/2 study (S4-13-001). In Phase 2, patients received silmitasertib 1000 mg twice daily for 10 days with G+C on Days 1 and 8 of a 21-day cycle. Primary efficacy endpoint was progression-free survival (PFS) in the modified intent-to-treat population (defined as patients who completed at least one cycle of silmitasertib without dose interruption/reduction) from both phases (silmitasertib/G+C n = 55, G+C n = 29). The response was assessed by Response Evaluation Criteria in Solid Tumors v1.1. The median PFS was 11.2 months (95% confidence interval [CI], 7.6, 14.7) versus 5.8 months (95% CI, 3.1, not evaluable [NE]) ( p  = 0.0496); 10-month PFS was 56.1% (95% CI, 38.8%, 70.2%) versus 22.2% (95% CI, 1.8%, 56.7%); and median overall survival was 17.4 months (95% CI, 13.4, 25.7) versus 14.9 months (95% CI, 9.9, NE) with silmitasertib/G+C versus G+C. Overall response rate was 34.0% versus 30.8%; the disease control rate was 86.0% versus 88.5% with silmitasertib/G+C versus G+C. Almost all silmitasertib/G+C (99%) and G+C (93%) patients reported at least one treatment emergent adverse event (TEAE). The most common TEAEs (all grades) with silmitasertib/G+C versus G+C were diarrhea (70% versus 13%), nausea (59% vs. 30%), fatigue (47% vs. 47%), vomiting (39% vs. 7%), and anemia (39% vs. 30%). Twelve patients (10%) discontinued treatment because of TEAEs during the study. CONCLUSIONS: Silmitasertib/G+C demonstrated promising preliminary evidence of efficacy for the first-line treatment of patients with locally advanced/metastatic cholangiocarcinoma.


Asunto(s)
Neoplasias de los Conductos Biliares , Colangiocarcinoma , Humanos , Gemcitabina , Cisplatino/uso terapéutico , Desoxicitidina/uso terapéutico , Colangiocarcinoma/patología , Conductos Biliares Intrahepáticos/patología , Neoplasias de los Conductos Biliares/patología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos
4.
J Med Philos ; 49(2): 207-219, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38418092

RESUMEN

In order to promote social distancing during the recent COVID-19 pandemic, physicians and healthcare systems have made efforts to replace in-person with virtual clinic visits when feasible. While these efforts have been well received and seem compatible with sound clinical practice, they do not perfectly replicate the experience of a face-to-face exchange between doctor and patient. This essay attempts to describe features of the virtual visit that distinguish it from its face-to-face analog and considers the phenomenological work of Emmanuel Levinas in arguing that these differences may limit the force of the ethical summons a provider would otherwise experience before the face of a patient. The diminishment of this signal therapeutic experience may engender vocational as well as clinical consequences, which should be weighed against the practical benefits of the virtual visit as we consider whether our enthusiasm for this mode of practice should continue.


Asunto(s)
COVID-19 , Aplicaciones Móviles , Médicos , Telemedicina , Humanos , Pandemias
5.
Emerg Infect Dis ; 29(10): 2032-2043, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37735741

RESUMEN

To examine protective and risk factors for Buruli ulcer (BU), we conducted a case-control study of 245 adult BU cases and 481 postcode-matched controls across BU-endemic areas of Victoria, Australia. We calculated age- and sex-adjusted odds ratios for socio-environmental, host, and behavioral factors associated with BU by using conditional logistic regression. Odds of BU were >2-fold for persons with diabetes mellitus and persons working outdoors who had soil contact in BU-endemic areas (compared with indoor work) but were lower among persons who had bacillus Calmette-Guérin vaccinations. BU was associated with increasing numbers of possums and with ponds and bore water use at residences. Using insect repellent, covering arms and legs outdoors, and immediately washing wounds were protective; undertaking multiple protective behaviors was associated with the lowest odds of BU. Skin hygiene/protection behaviors and previous bacillus Calmette-Guérin vaccination might provide protection against BU in BU-endemic areas.


Asunto(s)
Vacuna BCG , Úlcera de Buruli , Adulto , Humanos , Úlcera de Buruli/epidemiología , Úlcera de Buruli/prevención & control , Estudios de Casos y Controles , Factores de Riesgo , Victoria/epidemiología
6.
J Hepatol ; 79(2): 378-393, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37061197

RESUMEN

BACKGROUND & AIMS: The prevalence of non-alcoholic steatohepatitis (NASH)-driven hepatocellular carcinoma (HCC) is rising rapidly, yet its underlying mechanisms remain unclear. Herein, we aim to determine the role of hypoxia-inducible lipid droplet associated protein (HILPDA)/hypoxia-inducible gene 2 (HIG2), a selective inhibitor of intracellular lipolysis, in NASH-driven HCC. METHODS: The clinical significance of HILPDA was assessed in human NASH-driven HCC specimens by immunohistochemistry and transcriptomics analyses. The oncogenic effect of HILPDA was assessed in human HCC cells and in 3D epithelial spheroids upon exposure to free fatty acids and either normoxia or hypoxia. Lipidomics profiling of wild-type and HILPDA knockout HCC cells was assessed via shotgun and targeted approaches. Wild-type (Hilpdafl/fl) and hepatocyte-specific Hilpda knockout (HilpdaΔHep) mice were fed a Western diet and high sugar in drinking water while receiving carbon tetrachloride to induce NASH-driven HCC. RESULTS: In patients with NASH-driven HCC, upregulated HILPDA expression is strongly associated with poor survival. In oxygen-deprived and lipid-loaded culture conditions, HILPDA promotes viability of human hepatoma cells and growth of 3D epithelial spheroids. Lack of HILPDA triggered flux of polyunsaturated fatty acids to membrane phospholipids and of saturated fatty acids to ceramide synthesis, exacerbating lipid peroxidation and apoptosis in hypoxia. The apoptosis induced by HILPDA deficiency was reversed by pharmacological inhibition of ceramide synthesis. In our experimental mouse model of NASH-driven HCC, HilpdaΔHep exhibited reduced hepatic steatosis and tumorigenesis but increased oxidative stress in the liver. Single-cell analysis supports a dual role of hepatic HILPDA in protecting HCC cells and facilitating the establishment of a pro-tumorigenic immune microenvironment in NASH. CONCLUSIONS: Hepatic HILPDA is a pivotal oncometabolic factor in the NASH liver microenvironment and represents a potential novel therapeutic target. IMPACT AND IMPLICATIONS: Non-alcoholic steatohepatitis (NASH, chronic metabolic liver disease caused by buildup of fat, inflammation and damage in the liver) is emerging as the leading risk factor and the fastest growing cause of hepatocellular carcinoma (HCC), the most common form of liver cancer. While curative therapeutic options exist for HCC, it frequently presents at a late stage when such options are no longer effective and only systemic therapies are available. However, systemic therapies are still associated with poor efficacy and some side effects. In addition, no approved drugs are available for NASH. Therefore, understanding the underlying metabolic alterations occurring during NASH-driven HCC is key to identifying new cancer treatments that target the unique metabolic needs of cancer cells.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Enfermedad del Hígado Graso no Alcohólico , Animales , Humanos , Ratones , Carcinoma Hepatocelular/metabolismo , Ceramidas/metabolismo , Modelos Animales de Enfermedad , Ácidos Grasos/metabolismo , Hipoxia/metabolismo , Hígado/patología , Neoplasias Hepáticas/genética , Ratones Endogámicos C57BL , Ratones Noqueados , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Microambiente Tumoral
7.
J Hepatol ; 78(1): 142-152, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36162702

RESUMEN

BACKGROUND & AIMS: There is an unmet need to develop novel, effective medical therapies for cholangiocarcinoma (CCA). The Hippo pathway effector, Yes-associated protein (YAP), is oncogenic in CCA, but has historically been difficult to target therapeutically. Recently, we described a novel role for the LCK proto-oncogene, Src family tyrosine kinase (LCK) in activating YAP through tyrosine phosphorylation. This led to the hypothesis that LCK is a viable therapeutic target in CCA via regulation of YAP activity. METHODS: A novel tyrosine kinase inhibitor with relative selectivity for LCK, NTRC 0652-0, was pharmacodynamically profiled in vitro and in CCA cells. A panel of eight CCA patient-derived organoids were characterized and tested for sensitivity to NTRC 0652-0. Two patient-derived xenograft models bearing fibroblast growth factor receptor 2 (FGFR2)-rearrangements were utilized for in vivo assessment of pharmacokinetics, toxicity, and efficacy. RESULTS: NTRC 0652-0 demonstrated selectivity for LCK inhibition in vitro and in CCA cells. LCK inhibition with NTRC 0652-0 led to decreased tyrosine phosphorylation, nuclear localization, and co-transcriptional activity of YAP, and resulted in apoptotic cell death in CCA cell lines. A subset of tested patient-derived organoids demonstrated sensitivity to NTRC 0652-0. CCAs with FGFR2 fusions were identified as a potentially susceptible and clinically relevant genetic subset. In patient-derived xenograft models of FGFR2 fusion-positive CCA, daily oral treatment with NTRC 0652-0 resulted in stable plasma and tumor drug levels, acceptable toxicity, decreased YAP tyrosine phosphorylation, and significantly decreased tumor growth. CONCLUSIONS: A novel LCK inhibitor, NTRC 0652-0, inhibited YAP signaling and demonstrated preclinical efficacy in CCA cell lines, and patient-derived organoid and xenograft models. IMPACT AND IMPLICATIONS: Although aberrant YAP activation is frequently seen in CCA, YAP targeted therapies are not yet clinically available. Herein we show that a novel LCK-selective tyrosine kinase inhibitor (NTRC 0652-0) effectively inhibits YAP tyrosine phosphorylation and cotranscriptional activity and is well tolerated and cytotoxic in multiple preclinical models. The data suggest this approach may be effective in CCA with YAP dependence or FGFR2 fusions, and these findings warrant further investigation in phase I clinical trials.


Asunto(s)
Neoplasias de los Conductos Biliares , Colangiocarcinoma , Humanos , Neoplasias de los Conductos Biliares/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Fosfoproteínas/genética , Factores de Transcripción/metabolismo , Regulación Neoplásica de la Expresión Génica , Proteínas Señalizadoras YAP , Colangiocarcinoma/genética , Conductos Biliares Intrahepáticos/patología , Tirosina/genética , Tirosina/metabolismo , Tirosina/uso terapéutico , Línea Celular Tumoral
8.
Lupus ; 32(7): 815-826, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37249240

RESUMEN

OBJECTIVE: To explore initiation, persistence, and adherence to second-line prescribed treatments for SLE, specifically regarding the immunosuppressants azathioprine, methotrexate, and mycophenolate (conventional DMARDs), and belimumab (a biologic). METHODS: Clinical and insurance records were obtained for 801 patients with SLE who initiated treatment with azathioprine, belimumab, methotrexate, or mycophenolate between July 2015 and June 2019. The date of initiation defined the index date, with a 6-month pre-index and 12-month post-index period. Patient characteristics (age, gender, race, sex, ethnicity, geographic region of the US, diagnosing specialty, and type of insurance) and treatment patterns were tabulated overall and by each index medication. Logistic regression was used to model predictors of persistence for the entire sample and for each treatment cohort. FINDINGS: Approximately one-third of patients initiated methotrexate (n = 282, 35.2%) or mycophenolate (n = 258, 32.2%), with the remaining receiving azathioprine (n = 173, 21.6%) or belimumab (n = 88, 11.0%). 30% of patients were persistent with their index immunosuppressant therapy over the 12-month follow-up. The most common non-persistent treatment pattern was discontinuation which occurred in 55% of patients and was highest in the mycophenolate (58%) and lowest in the azathioprine (47%) groups. In total, 17% of patients switched to a different immunosuppressant, which was highest for the belimumab (25%) group. The average time to discontinuation was over 3 months and average time to switch was about 5 months, with patients receiving azathioprine tending to have shorter and belimumab having longer times to discontinuation or switch.Predictors of persistence were limited. Patients under the care of rheumatologists versus primary care and having higher co-morbidity assessed by CCI were associated with non-persistence for the overall sample. Race, number of SLE-related medications, census region, sex, and age were not found to be significantly related to non-persistence of immunosuppressants in this study.


Asunto(s)
Inmunosupresores , Lupus Eritematoso Sistémico , Humanos , Adulto , Estados Unidos , Inmunosupresores/uso terapéutico , Lupus Eritematoso Sistémico/tratamiento farmacológico , Azatioprina/uso terapéutico , Metotrexato/uso terapéutico , Estudios Retrospectivos , Resultado del Tratamiento
9.
Clin Gastroenterol Hepatol ; 20(5): 1019-1028.e3, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-34607017

RESUMEN

BACKGROUND & AIMS: In addition to gastric sensorimotor dysfunctions, functional dyspepsia (FD) is also variably associated with duodenal micro-inflammation and epithelial barrier dysfunction, the pathogenesis and clinical significance of which are unknown. Our hypothesis was that miRNAs and/or inflammation degrade epithelial barrier proteins, resulting in increased duodenal mucosal permeability in FD. METHODS: We compared the duodenal mucosal gene expression and miRNAs, in vivo permeability (lactulose-mannitol excretion between 0 and 60 and 60 and 120 minutes after saccharide ingestion), ex vivo assessments (transmucosal resistance, fluorescein isothiocyanate [FITC]-dextran flux, and basal ion transport), and duodenal histology (light and electron microscopy) in 40 patients with FD and 24 controls. RESULTS: Compared with controls, the mRNA expression of several barrier proteins (zonula occludens-1, occludin, claudin-12, and E-cadherin) was modestly reduced (ie, a fold change of 0.8-0.85) in FD with increased expression of several miRNAs (eg, miR-142-3p and miR-144-3-p), which suppress these genes. The urinary lactulose excretion and the lactulose:mannitol ratio between 60 and 120 minutes were greater in FD than in controls (P < .05). The FITC-dextran flux, which reflects paracellular permeability, was inversely correlated (r = -0.32, P = .03) with transmucosal resistance and directly correlated (r = 0.4, P = .02) with lactulose:mannitol ratio. Other parameters (mucosal eosinophils, intraepithelial lymphocytes, and mast cells, transmucosal resistance, FITC-dextran flux, average intercellular distance, and proportion of dilated junctions) were not significantly different between groups. CONCLUSIONS: In FD, there is a modest reduction in the expression of several duodenal epithelial barrier proteins, which may be secondary to up-regulation of regulatory miRNAs, and increased small intestinal permeability measured in vivo.


Asunto(s)
Dispepsia , MicroARNs , Dispepsia/patología , Humanos , Inflamación/patología , Mucosa Intestinal/patología , Lactulosa , Manitol/metabolismo , MicroARNs/genética , Permeabilidad , Uniones Estrechas/metabolismo , Uniones Estrechas/patología
10.
Hepatology ; 74(3): 1411-1428, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33735525

RESUMEN

BACKGROUND AND AIMS: Existing therapeutic approaches to treat cholangiocarcinoma (CCA) have limited effectiveness, prompting further study to develop therapies for CCA. We report a mechanistic role for the heparan sulfate editing enzyme sulfatase 2 (SULF2) in CCA pathogenesis. APPROACH AND RESULTS: In silico analysis revealed elevated SULF2 expression in human CCA samples, occurring partly through gain of SULF2 copy number. We examined the effects of knockdown or overexpression of SULF2 on tumor growth, chemoresistance, and signaling pathway activity in human CCA cell lines in vitro. Up-regulation of SULF2 in CCA leads to increased platelet-derived growth factor receptor beta (PDGFRß)-Yes-associated protein (YAP) signaling activity, promoting tumor growth and chemotherapy resistance. To explore the utility of targeting SULF2 in the tumor microenvironment for CCA treatment, we tested an anti-SULF2 mouse monoclonal antibody, 5D5, in a mouse CCA xenograft model. Targeting SULF2 by monoclonal antibody 5D5 inhibited PDGFRß-YAP signaling and tumor growth in the mouse xenograft model. CONCLUSIONS: These results suggest that SULF2 monoclonal antibody 5D5 or related agents may be potentially promising therapeutic agents in CCA.


Asunto(s)
Neoplasias de los Conductos Biliares/genética , Colangiocarcinoma/genética , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/metabolismo , Sulfatasas/genética , Proteínas Señalizadoras YAP/metabolismo , Animales , Anticuerpos Monoclonales/farmacología , Neoplasias de los Conductos Biliares/metabolismo , Proliferación Celular/efectos de los fármacos , Proliferación Celular/genética , Colangiocarcinoma/metabolismo , Resistencia a Antineoplásicos/efectos de los fármacos , Resistencia a Antineoplásicos/genética , Técnicas de Silenciamiento del Gen , Humanos , Ratones , Trasplante de Neoplasias , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/efectos de los fármacos , Sulfatasas/antagonistas & inhibidores , Sulfatasas/metabolismo , Microambiente Tumoral , Ensayos Antitumor por Modelo de Xenoinjerto , Proteínas Señalizadoras YAP/efectos de los fármacos
11.
Med J Aust ; 216(7): 349-356, 2022 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-35224751

RESUMEN

OBJECTIVE: To examine associations between area-level socio-economic factors and the incidence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections in Victoria during 2020. DESIGN, SETTING: Population-level ecological study of the incidence of SARS-CoV-2 infections in Victoria, by postcode, 1 March - 13 August 2020. MAIN OUTCOME MEASURES: Relationships between the incidence of SARS-CoV-2 infections by postcode (Department of Health and Human Services data published on The Age website), and demographic, education level, ethnic background, economic and employment-related factors, housing-related factors, and social disadvantage (Australian Bureau of Statistics data for 2014-19), expressed as incidence rate ratios (IRRs). RESULTS: During the study period, 15 482 SARS-CoV-2 infections with associated postcodes were recorded in Victoria. Incidence was higher for metropolitan than regional postcodes (418.3 v 62 infections per 100 000 population; IRR, 6.2; 95% CI, 4.6-8.2). In regional postcodes, incidence rose with mean household size (per person: IRR, 7.30; 95% CI, 4.37-12.2), unemployment proportion (per percentage point: IRR, 1.50; 95% CI, 1.33-1.69), and proportions for whom rent (IRR, 1.15; 95% CI, 1.07-1.22) or mortgage repayments (IRR, 1.22; 95% CI, 1.15-1.28) exceeded 30% of household income. In metropolitan areas, incidence increased with unemployment proportion (IRR, 1.14; 95% CI, 1.05-1.23) and proportion without paid leave (IRR, 1.22; 95% CI, 1.02-1.45). Incidence also increased with proportion speaking languages other than English at home (regional: IRR, 1.08; 95% CI, 1.06-1.11; metropolitan: IRR, 1.01; 95% CI, 1.002-1.02) and with Indigenous Australian proportion (metropolitan only: IRR, 1.91; 95% CI, 1.10-2.73). CONCLUSIONS: Socio-economic factors may have contributed to the non-homogeneous incidence of SARS-CoV-2 infections across Victoria during 2020.


Asunto(s)
COVID-19 , Australia , COVID-19/epidemiología , Factores Económicos , Humanos , Incidencia , SARS-CoV-2
12.
J Med Philos ; 47(1): 95-116, 2022 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-35137171

RESUMEN

The dominant model for bioethical inquiry taught in medical schools is that of principlism. The heritage of this methodology can be traced to the Enlightenment project of generating a universalizable justification for normative morality arising from within the individual, rational agent. This project has been criticized by Alasdair MacIntyre who suggests that its failure has resulted in a fragmented and incoherent contemporary ethical framework characterized by fundamental intractability in moral debate. This incoherence implicates principlist conceptions of bioethics. Medical ethics as practiced, though, is partially in keeping with teleological alternatives to principlism. Nonetheless, the hegemony of principlism threatens to harm the practice of good medicine whenever it is used to provide justification for the sanction or prohibition of practices, despite not being equipped to grant moral authority to such justifications. An example of this failure and its resulting harm is expressed in the growing obsolescence of living donor liver transplantation.


Asunto(s)
Bioética , Trasplante de Hígado , Análisis Ético , Teoría Ética , Ética Médica , Humanos , Donadores Vivos , Principios Morales , Narración , Ética Basada en Principios
13.
Langmuir ; 37(46): 13610-13616, 2021 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-34752697

RESUMEN

Surfactants are often added to aqueous solutions to induce spreading on otherwise unwettable hydrophobic surfaces. Alternatively, they can be introduced directly into solid hydrophobic materials─such as the soft elastomer, polydimethylsiloxane─to induce autonomous wetting without requiring additional surface or liquid modifications. Given the similarity between mechanisms of these two approaches, models that describe wetting by aqueous surfactant solutions should also characterize wetting on surfactant-solid systems. To investigate this theory, multiple surfactants of varying size and chemical composition were added to prepolymerized PDMS samples. After cross-linking, water droplets were placed on the surfaces at set time points, and their contact angles were recorded to track the temporal evolution of the interfacial tension. Multiple nonlinear models were fitted to this data, their parameters were analyzed, and each goodness of fit was compared. An empirical model of dynamic surface tension was found to describe the wetting process better than the single established model found in the literature. The proposed model adapted better to the longer time scales induced by slow molecular diffusivity in PDMS. Siloxane ethoxylate surfactants induced faster and more complete wetting of PDMS by water than oxyoctylphenol ethoxylates did. The generalizability of this model for characterizing nonionic surfactants of a wide range of physiochemical properties was demonstrated.


Asunto(s)
Dimetilpolisiloxanos , Tensoactivos , Interacciones Hidrofóbicas e Hidrofílicas , Tensión Superficial , Humectabilidad
14.
J Immunol ; 203(7): 1952-1960, 2019 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-31471525

RESUMEN

IL-33, an IL-1 family cytokine, is constitutively expressed in mucosal tissues and other organs in healthy humans and animals, and expression levels increase in inflammatory conditions. Although IL-33-mediated promotion of type 2 immune responses has been well established, a gap in our knowledge regarding the functional diversity of this pleiotropic cytokine remains. To address this gap, we developed a new IL-33 transgenic mouse model in which overexpression of full-length IL-33 is induced in lung epithelial cells under conditional control. In adult mice, an ∼3-fold increase in the steady-state IL-33 levels produced no pathologic effects in the lungs. When exposed to airborne allergens, adult transgenic mice released more IL-33 extracellularly and exhibited robust type 2 immune responses. In neonatal transgenic mice, up to postnatal day 14, a similar increase in steady-state IL-33 levels resulted in increased mortality, enlarged alveolar spaces resembling bronchopulmonary dysplasia, and altered expression of genes associated with tissue morphogenesis. Processed 25-kDa IL-33 protein was detected in bronchoalveolar lavage fluids without any exogenous stimuli, and pathologic changes were abolished in mice deficient in the IL-33 receptor ST2. These findings suggest that adult lungs are relatively resistant to IL-33 overexpression unless they encounter environmental insults, whereas developing lungs are highly susceptible, with IL-33 overexpression resulting in detrimental and pathologic outcomes.


Asunto(s)
Alérgenos/inmunología , Displasia Broncopulmonar/inmunología , Exposición a Riesgos Ambientales/efectos adversos , Proteína 1 Similar al Receptor de Interleucina-1/inmunología , Interleucina-33/inmunología , Alveolos Pulmonares/inmunología , Animales , Animales Recién Nacidos , Displasia Broncopulmonar/patología , Células Epiteliales/inmunología , Células Epiteliales/patología , Proteína 1 Similar al Receptor de Interleucina-1/genética , Interleucina-33/genética , Ratones , Ratones Noqueados , Alveolos Pulmonares/patología
15.
Ann Vasc Surg ; 77: 243-254, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34437971

RESUMEN

OBJECTIVES: The aim of this study was to test the hypothesis that endovascular aspiration thrombectomy of right atrial thrombus (RAT) using the AngioVac device is as safe and effective in patients with cancer as those without cancer. BACKGROUND: RAT is a uniquely challenging clinical presentation of venous thromboembolism due to its low incidence and historically high-risk of mortality due to thrombus propagation into the pulmonary arteries. There is a lack of consensus regarding management, particularly in high-risk cancer patients. Endovascular aspiration thrombectomy utilizing the AngioVac device is effective in removal of right atrial thrombus and may be a safer option for patients with cancer in whom avoidance of higher-risk intervention is preferred. METHODS: This was an institutional review board-approved retrospective single-center case control study of patients with RAT who underwent AngioVac aspiration thrombectomy between August 2013 and July 2020. Analysis of patient demographics and clinical characteristics, thrombus-related factors, and operative details was performed. Primary endpoints included survival, safety, and technical success. RESULTS: A total of 44 patients met inclusion criteria, 20 of whom with active malignancy. The oncology group had a significantly higher Charlson comorbidity index (P = 0.01). Comparative outcomes between the oncology and non-oncology group showed no difference in survival (P = 0.8) or technical success (OR 3, 95% CI 0.83-10.9). There were 9 complications, including 6 minor, 1 moderate, 1 severe, and 1 death. CONCLUSIONS: AngioVac aspiration thrombectomy of RAT is as safe and effective in patients with cancer as those without cancer.


Asunto(s)
Cardiopatías/terapia , Neoplasias/complicaciones , Trombectomía/instrumentación , Trombosis/terapia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Comorbilidad , Femenino , Cardiopatías/complicaciones , Cardiopatías/diagnóstico por imagen , Cardiopatías/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/diagnóstico , Neoplasias/mortalidad , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Trombectomía/efectos adversos , Trombectomía/mortalidad , Trombosis/complicaciones , Trombosis/diagnóstico por imagen , Trombosis/mortalidad , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
16.
Am J Otolaryngol ; 42(5): 103004, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33812207

RESUMEN

PURPOSE: To evaluate the frequency and types of humoral immunodeficiencies (HID) in pediatric and adult patients with recurrent (RARS). Patients with HID commonly present with upper respiratory tract infections. Their pathophysiology in children is different than adult counterparts. It is unknown how HID affects those two age groups. MATERIALS AND METHODS: We performed a retrospective chart review of pediatric (<18 years old) and adult (18 years and older) patients who were evaluated in our pediatric and adult rhinology clinic between July 2010 and December 2020 and had the diagnosis of recurrent (>3 times/year) rhinosinusitis. Patients with cystic fibrosis, Aspirin Exacerbated Respiratory Disease (AERD), and ciliary dyskinesia were excluded. Demographic data and associated conditions were reviewed. Immunologic evaluation included complete blood cell count (CBC) with differential, serum immunoglobulin G, A, and M levels, and baseline and post-vaccination pneumococcal antibody titers. RESULTS: There were 135 patients who met the inclusion criteria. 86 patients (63.7%) were children, 49 patients (36.3%) were adults. 46.5% of the pediatric patients and 45% of the adult patients were female. 17.4% of children had abnormal immunologic findings: 8 had hypogammaglobulinemia (p < 0.0001), 2 had specific antibody deficiency (SAD), and 5 had selective IgA deficiency. 32.7% of adults (p < 0.0001) had abnormal immunologic findings: 4 had hypogammaglobulinemia, 11 had SAD (p < 0.0001), and 1 patient had both IgA deficiency and SAD. CONCLUSION: Humoral immunodeficiency, specifically SAD, seems to be more common in adult versus pediatric RARS that is refractory to treatment.


Asunto(s)
Síndromes de Inmunodeficiencia/complicaciones , Síndromes de Inmunodeficiencia/inmunología , Rinitis/inmunología , Sinusitis/inmunología , Enfermedad Aguda , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Niño , Femenino , Humanos , Inmunidad Humoral , Inmunoglobulinas/sangre , Síndromes de Inmunodeficiencia/epidemiología , Masculino , Persona de Mediana Edad , Recurrencia , Estudios Retrospectivos , Rinitis/epidemiología , Rinitis/etiología , Sinusitis/epidemiología , Sinusitis/etiología , Adulto Joven
17.
Subst Abus ; 42(4): 896-904, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33705253

RESUMEN

Background: Interactions with healthcare workers can provide effective entrance into treatment, ensuring retention and lifelong recovery for individuals with Substance Use Disorder (SUD). Healthcare providers approach the challenges of patient management with different skills, comfort levels, and viewpoints. Individuals in recovery also provide crucial perspectives relevant to the complex aspects of the drug epidemic. The purpose of this study was to determine if perceptions of SUD diverge among individuals in recovery, physicians, nurses and medical students. Methods: A survey consisting of 29 Likert statements was deployed to physicians, nurses, medical students, and persons with SUD in recovery. Respondents were asked to rate their level of agreement on statements about SUD such as treatment, stigma, medications for opioid use disorder (MOUD), naloxone kits, safe injection sites, and methamphetamine usage. Separate Welch's analysis of variances (ANOVAs) were conducted to determine differences between the respondent groups and each statement. For any statistically significant findings, Games-Howell post-hoc analyses were employed. Results: A total of 523 individuals provided survey responses: individuals in recovery (n = 111), physicians (n = 113), nurses (n = 206), and medical students (n = 93). Survey results revealed the majority of items had statistically significant differences in respondent groups. Perceptions diverged on items related to treatment, stigma, MOUD, take-home naloxone kits, safe injection sites, needle exchange programs, and methamphetamine. Conclusion: As healthcare providers and policymakers develop treatment strategies to engage those with SUD in quality treatment, they will benefit from understanding how different viewpoints on SUD affect treatment for these individuals. These attitudes impact stigma, willingness to prescribe new treatments, and development of clinical relationships. The insight from this study allows for important discussions on the substance use health crisis and further inquiry on why these differences exist and how the diverging viewpoints may impact the lives of persons with SUD.


Asunto(s)
Trastornos Relacionados con Opioides , Médicos , Estudiantes de Medicina , Humanos , Naloxona/uso terapéutico , Trastornos Relacionados con Opioides/tratamiento farmacológico , Estigma Social
18.
Clin Infect Dis ; 70(9): 1993-1997, 2020 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-31231766

RESUMEN

BACKGROUND: Antibiotics are highly effective in curing Mycobacterium ulcerans lesions, but are associated with significant toxicity. In those not undergoing surgery, we compared 6 weeks with the currently recommended 8 weeks of combination antibiotic therapy for small M. ulcerans lesions. METHODS: Mycobacterium ulcerans cases from an observational cohort at Barwon Health, Victoria, treated with antibiotics alone from 1 October 2010 to 31 March 2018 were included. The 6-week antibiotic group received ≥28 days and ≤42 days and the 8-week antibiotic group received ≥56 days of antibiotic therapy, respectively. Only World Health Organization category 1 lesions were included. RESULTS: 207 patients were included; 53 (25.6%) in the 6-week group and 154 (74.4%) in the 8-week group. The median age of patients was 53 years (interquartile range [IQR], 33-69 years) and 100 (48.3%) were female. Lesions were ≤900 mm2 in size in 79.7% of patients and 93.2% were ulcerative. Fifty-three patients (100%) achieved treatment cure in the 6-week group compared with 153 (99.4%) in the 8-week group (P = .56). No patients died or were lost to follow-up during the study. Median time to heal was 70 days (IQR, 60-96 days) in the 6-week group and 128 days (IQR, 95-173 days) in the 8-week group (P < .001). Two (3.8%) patients in the 6-week group experienced a paradoxical reaction compared with 39 (25.3%) patients in the 8-week group (P = .001). CONCLUSIONS: For selected small M. ulcerans lesions, 6 weeks may be as effective as 8 weeks of combined antibiotic therapy in curing lesions without surgery.


Asunto(s)
Úlcera de Buruli , Mycobacterium ulcerans , Adulto , Anciano , Antibacterianos/uso terapéutico , Australia , Úlcera de Buruli/tratamiento farmacológico , Estudios de Cohortes , Femenino , Humanos , Persona de Mediana Edad
19.
Artículo en Inglés | MEDLINE | ID: mdl-32571813

RESUMEN

Combination antibiotic therapy is highly effective in curing Buruli ulcer (BU) caused by Mycobacterium ulcerans Treatment failures have been uncommonly reported with the recommended 56 days of antibiotics, and little is known about risk factors for treatment failure. We analyzed treatment failures among BU patients treated with ≥56 days of antibiotics from a prospective observational cohort at Barwon Health, Victoria, from 1 January 1998 to 31 December 2018. Treatment failure was defined as culture-positive recurrence within 12 months of commencing antibiotics under the following conditions: (i) following failure to heal the initial lesion or (ii) a new lesion developing at the original or at a new site. A total of 430 patients received ≥56 days of antibiotic therapy, with a median duration of 56 days (interquartile range [IQR], 56 to 80). Seven (1.6%) patients experienced treatment failure. For six adult patients experiencing treatment failure, all were male, weighed >90 kg, did not have surgery, and received combination rifampin-clarithromycin (median rifampin dose, 5.6 mg per kg of body weight per day; median clarithromycin dose, 8.1 mg/kg/day). When compared to those who did not fail treatment on univariate analysis, treatment failure was significantly associated with a weight of >90 kg (P < 0.001), male gender (P = 0.02), immune suppression (P = 0.04), and a first-line regimen of rifampin-clarithromycin compared to a regimen of rifampin-fluoroquinolone (P = 0.05). There is a low rate of treatment failure in Australian BU patients treated with rifampin-based oral combination antibiotic therapy. Our study raises the possibility that treatment failure risk may be increased in males, those with a body weight of >90 kg, those with immune suppression, and those taking rifampin-clarithromycin antibiotic regimens, but future pharmacokinetic and pharmacodynamics studies are required to determine the validity of these hypotheses.


Asunto(s)
Úlcera de Buruli , Mycobacterium ulcerans , Adulto , Antibacterianos/uso terapéutico , Australia , Úlcera de Buruli/tratamiento farmacológico , Quimioterapia Combinada , Femenino , Humanos , Masculino , Factores de Riesgo , Insuficiencia del Tratamiento
20.
Gastroenterology ; 157(1): 210-226.e12, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30878468

RESUMEN

BACKGROUND & AIMS: The CCNE1 locus, which encodes cyclin E1, is amplified in many types of cancer cells and is activated in hepatocellular carcinomas (HCCs) from patients infected with hepatitis B virus or adeno-associated virus type 2, due to integration of the virus nearby. We investigated cell-cycle and oncogenic effects of cyclin E1 overexpression in tissues of mice. METHODS: We generated mice with doxycycline-inducible expression of Ccne1 (Ccne1T mice) and activated overexpression of cyclin E1 from age 3 weeks onward. At 14 months of age, livers were collected from mice that overexpress cyclin E1 and nontransgenic mice (controls) and analyzed for tumor burden and by histology. Mouse embryonic fibroblasts (MEFs) and hepatocytes from Ccne1T and control mice were analyzed to determine the extent to which cyclin E1 overexpression perturbs S-phase entry, DNA replication, and numbers and structures of chromosomes. Tissues from 4-month-old Ccne1T and control mice (at that age were free of tumors) were analyzed for chromosome alterations, to investigate the mechanisms by which cyclin E1 predisposes hepatocytes to transformation. RESULTS: Ccne1T mice developed more hepatocellular adenomas and HCCs than control mice. Tumors developed only in livers of Ccne1T mice, despite high levels of cyclin E1 in other tissues. Ccne1T MEFs had defects that promoted chromosome missegregation and aneuploidy, including incomplete replication of DNA, centrosome amplification, and formation of nonperpendicular mitotic spindles. Whereas Ccne1T mice accumulated near-diploid aneuploid cells in multiple tissues and organs, polyploidization was observed only in hepatocytes, with losses and gains of whole chromosomes, DNA damage, and oxidative stress. CONCLUSIONS: Livers, but not other tissues of mice with inducible overexpression of cyclin E1, develop tumors. More hepatocytes from the cyclin E1-overexpressing mice were polyploid than from control mice, and had losses or gains of whole chromosomes, DNA damage, and oxidative stress; all of these have been observed in human HCC cells. The increased risk of HCC in patients with hepatitis B virus or adeno-associated virus type 2 infection might involve activation of cyclin E1 and its effects on chromosomes and genomes of liver cells.


Asunto(s)
Adenoma de Células Hepáticas/genética , Carcinoma Hepatocelular/genética , Inestabilidad Cromosómica/genética , Ciclina E/genética , Neoplasias Hepáticas/genética , Hígado/metabolismo , Proteínas Oncogénicas/genética , Adenoma de Células Hepáticas/patología , Adenoma de Células Hepáticas/virología , Animales , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/virología , Estructuras Cromosómicas , Daño del ADN/genética , Replicación del ADN , Dependovirus , Fibroblastos , Hepatitis B Crónica , Hepatocitos , Hígado/patología , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/virología , Neoplasias Hepáticas Experimentales/genética , Neoplasias Hepáticas Experimentales/patología , Ratones , Estrés Oxidativo/genética , Infecciones por Parvoviridae , Parvovirinae , Poliploidía , Puntos de Control de la Fase S del Ciclo Celular
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