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1.
J Exp Clin Cancer Res ; 43(1): 64, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38424636

RESUMO

Colorectal cancer (CRC) is a heterogenous malignancy underpinned by dysregulation of cellular signaling pathways. Previous literature has implicated aberrant JAK/STAT3 signal transduction in the development and progression of solid tumors. In this study we investigate the effectiveness of inhibiting JAK/STAT3 in diverse CRC models, establish in which contexts high pathway expression is prognostic and perform in depth analysis underlying phenotypes. In this study we investigated the use of JAK inhibitors for anti-cancer activity in CRC cell lines, mouse model organoids and patient-derived organoids. Immunohistochemical staining of the TransSCOT clinical trial cohort, and 2 independent large retrospective CRC patient cohorts was performed to assess the prognostic value of JAK/STAT3 expression. We performed mutational profiling, bulk RNASeq and NanoString GeoMx® spatial transcriptomics to unravel the underlying biology of aberrant signaling. Inhibition of signal transduction with JAK1/2 but not JAK2/3 inhibitors reduced cell viability in CRC cell lines, mouse, and patient derived organoids (PDOs). In PDOs, reduced Ki67 expression was observed post-treatment. A highly significant association between high JAK/STAT3 expression within tumor cells and reduced cancer-specific survival in patients with high stromal invasion (TSPhigh) was identified across 3 independent CRC patient cohorts, including the TrasnSCOT clinical trial cohort. Patients with high phosphorylated STAT3 (pSTAT3) within the TSPhigh group had higher influx of CD66b + cells and higher tumoral expression of PDL1. Bulk RNAseq of full section tumors showed enrichment of NFκB signaling and hypoxia in these cases. Spatial deconvolution through GeoMx® demonstrated higher expression of checkpoint and hypoxia-associated genes in the tumor (pan-cytokeratin positive) regions, and reduced lymphocyte receptor signaling in the TME (pan-cytokeratin- and αSMA-) and αSMA (pan-cytokeratin- and αSMA +) areas. Non-classical fibroblast signatures were detected across αSMA + regions in cases with high pSTAT3. Therefore, in this study we have shown that inhibition of JAK/STAT3 represents a promising therapeutic strategy for patients with stromal-rich CRC tumors. High expression of JAK/STAT3 proteins within both tumor and stromal cells predicts poor outcomes in CRC, and aberrant signaling is associated with distinct spatially-dependant differential gene expression.


Assuntos
Neoplasias Colorretais , Humanos , Animais , Camundongos , Estudos Retrospectivos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Transdução de Sinais , Hipóxia , Queratinas/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Linhagem Celular Tumoral
2.
Asia Pac J Clin Oncol ; 20(2): 198-209, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37357383

RESUMO

Return to work (RTW) is a marker of functional recovery for working-age cancer survivors. Identifying factors that impact on RTW in cancer survivors is an essential step to guide further research and interventions to support RTW. This systematic review aimed to identify nontreatment, non-cancer-related variables impacting RTW in Australian cancer survivors. A systematic search was conducted in EMBASE, PsycINFO, CINAHL, PubMed, and Google Scholar. Studies were eligible if they included: (1) adults living post diagnosis of malignancy; (2) quantitative data for nontreatment, non-cancer-related variables impacting RTW; (3) only Australian participants. Included studies were critically appraised, and relevant data extracted and synthesized narratively. Six studies were included in the review, published between 2008 and 2020. Studies were of variable quality and mixed methodologies. One study included malignancies of any type with the remainder focusing on survivors of colorectal cancer (n = 3), oropharyngeal cancer (n = 1), and glioblastoma multiforme (n = 1). Multiple factors were related to RTW in individual studies, including older age, presence of three or more comorbidities, fewer work hours pre-morbidly, lower body mass index, longer than recommended sleep duration, and not having private health insurance; however, there was limited consistency in findings between studies. Other variables examined included: occupation type, household income, healthy lifestyle behaviors, flexibility, and duration of employment with workplace; however, no significant associations with RTW were reported. Further research is required to gather compelling evidence on factors that influence RTW in Australian cancer survivors.


Assuntos
Sobreviventes de Câncer , Neoplasias , Adulto , Humanos , Retorno ao Trabalho , Austrália/epidemiologia , Sobreviventes , Neoplasias/diagnóstico , Neoplasias/terapia
3.
Psychooncology ; 33(1): e6265, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38072641

RESUMO

OBJECTIVES: The number of colorectal cancer (CRC) survivors is increasing and current models of survivorship care are unsustainable. There is a drive to implement alternative models of care including shared care between general practitioners (GPs) and hospital-based providers. The primary objective of this study was to explore perspectives on facilitators and barriers to shared care. The secondary objective was to explore experiences of telehealth-delivered care. METHOD: Qualitative data were collected via semi-structured interviews with participants in the Shared Care for Colorectal Cancer Survivors (SCORE) randomised controlled trial. Interviews explored patient experiences of usual and shared survivorship care during the SCORE trial. In response to the COVID pandemic, participant experiences of telehealth appointments were also explored. Interviews were recorded and transcribed for thematic analysis. RESULTS: Twenty survivors of CRC were interviewed with an even number in the shared and usual care arms; 14 (70%) were male. Facilitators to shared care included: good relationships with GPs; convenience of GPs; good communication between providers; desire to reduce public health system pressures. Barriers included: poor communication between clinicians; inaccessibility of GPs; beliefs about GP capacity; and a preference for follow-up care with the hospital after positive treatment experiences. Participants also commonly expressed a preference for telehealth-based follow-up when there was no need for a clinical examination. CONCLUSIONS: This is one of few studies that have explored patient experiences with shared and telehealth-based survivorship care. Findings can guide the implementation of these models, particularly around care coordination, communication, preparation, and personalised pathways of care.


Assuntos
Sobreviventes de Câncer , Neoplasias Colorretais , Telemedicina , Feminino , Humanos , Masculino , Neoplasias Colorretais/terapia , Sobreviventes , Sobrevivência , Pesquisa Qualitativa , Ensaios Clínicos Controlados Aleatórios como Assunto
4.
J Pathol ; 261(4): 401-412, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37792663

RESUMO

Both lymph node metastases (LNMs) and tumour deposits (TDs) are included in colorectal cancer (CRC) staging, although knowledge regarding their biological background is lacking. This study aimed to compare the biology of these prognostic features, which is essential for a better understanding of their role in CRC spread. Spatially resolved transcriptomic analysis using digital spatial profiling was performed on TDs and LNMs from 10 CRC patients using 1,388 RNA targets, for the tumour cells and tumour microenvironment. Shotgun proteomics identified 5,578 proteins in 12 different patients. Differences in RNA and protein expression were analysed, and spatial deconvolution was performed. Image-based consensus molecular subtype (imCMS) analysis was performed on all TDs and LNMs included in the study. Transcriptome and proteome profiles identified distinct clusters for TDs and LNMs in both the tumour and tumour microenvironment segment, with upregulation of matrix remodelling, cell adhesion/motility, and epithelial-mesenchymal transition (EMT) in TDs (all p < 0.05). Spatial deconvolution showed a significantly increased abundance of fibroblasts, macrophages, and regulatory T-cells (p < 0.05) in TDs. Consistent with a higher fibroblast and EMT component, imCMS classified 62% of TDs as poor prognosis subtype CMS4 compared to 36% of LNMs (p < 0.05). Compared to LNMs, TDs have a more invasive state involving a distinct tumour microenvironment and upregulation of EMT, which are reflected in a more frequent histological classification of TDs as CMS4. These results emphasise the heterogeneity of locoregional spread and the fact that TDs should merit more attention both in future research and during staging. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.


Assuntos
Neoplasias Colorretais , Transcriptoma , Humanos , Metástase Linfática , Extensão Extranodal , Proteômica , Prognóstico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , RNA , Microambiente Tumoral
5.
J Pathol ; 261(1): 19-27, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37403270

RESUMO

Tumor budding (TB) is a strong biomarker of poor prognosis in colorectal cancer and other solid cancers. TB is defined as isolated single cancer cells or clusters of up to four cancer cells at the invasive tumor front. In areas with a large inflammatory response at the invasive front, single cells and cell clusters surrounding fragmented glands are observed appearing like TB. Occurrence of these small groups is referred to as pseudobudding (PsB), which arises due to external influences such as inflammation and glandular disruption. Using a combination of orthogonal approaches, we show that there are clear biological differences between TB and PsB. TB is representative of active invasion by presenting features of epithelial-mesenchymal transition and exhibiting increased deposition of extracellular matrix within the surrounding tumor microenvironment (TME), whereas PsB represents a reactive response to heavy inflammation where increased levels of granulocytes within the surrounding TME are observed. Our study provides evidence that areas with a strong inflammatory reaction should be avoided in the routine diagnostic assessment of TB. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.


Assuntos
Neoplasias , Humanos , Transição Epitelial-Mesenquimal , Inflamação , Reino Unido , Microambiente Tumoral
6.
Sci Rep ; 13(1): 9779, 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37328512

RESUMO

Developing materials with high efficiency for recovering oil to mitigate the environmental impact of oil spills has always been a challenging task. A commercial melamine formaldehyde sponge was coated with an optimised superhydrophobic/superoleophilic hyper-crosslinked polymer and applied to the removal of crude oil from oil-in-water emulsions for the improvement of oil spill clean-up processes. The high surface area, porosity, hydrophobicity, and selectivity of oil over water made the hyper-crosslinked polymer coated sponge (HPCS) an ideal sorbent for efficient oil/water separation. The system was able to strip crude oil from water emulsions of 1000 ppm to a negligible level of 2 ppm oil with minimal amounts of the HPCS material. More importantly, the HPCS material could be reused via a simple mechanical compression process, and the uptake capacity was retained over ten cycles. For five cycles of oil adsorption/mechanical compression the HPCS was able to provide water filtrate with oil concentrations of under 15 ppm. This is an effective and economical recovery system, removing the need for consistent solvent washing and drying processes. These results suggest that the HPCS is a promising material for oil/water separation and recovery under challenging conditions.


Assuntos
Poluição por Petróleo , Petróleo , Óleos , Poluição por Petróleo/análise , Emulsões , Petróleo/análise , Polímeros
8.
Eur Heart J Cardiovasc Pharmacother ; 9(4): 371-386, 2023 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-37019821

RESUMO

BACKGROUND: In post-coronavirus disease-19 (post-COVID-19) conditions (long COVID), systemic vascular dysfunction is implicated, but the mechanisms are uncertain, and the treatment is imprecise. METHODS AND RESULTS: Patients convalescing after hospitalization for COVID-19 and risk factor matched controls underwent multisystem phenotyping using blood biomarkers, cardiorenal and pulmonary imaging, and gluteal subcutaneous biopsy (NCT04403607). Small resistance arteries were isolated and examined using wire myography, histopathology, immunohistochemistry, and spatial transcriptomics. Endothelium-independent (sodium nitroprusside) and -dependent (acetylcholine) vasorelaxation and vasoconstriction to the thromboxane A2 receptor agonist, U46619, and endothelin-1 (ET-1) in the presence or absence of a RhoA/Rho-kinase inhibitor (fasudil), were investigated. Thirty-seven patients, including 27 (mean age 57 years, 48% women, 41% cardiovascular disease) 3 months post-COVID-19 and 10 controls (mean age 57 years, 20% women, 30% cardiovascular disease), were included. Compared with control responses, U46619-induced constriction was increased (P = 0.002) and endothelium-independent vasorelaxation was reduced in arteries from COVID-19 patients (P < 0.001). This difference was abolished by fasudil. Histopathology revealed greater collagen abundance in COVID-19 arteries {Masson's trichrome (MT) 69.7% [95% confidence interval (CI): 67.8-71.7]; picrosirius red 68.6% [95% CI: 64.4-72.8]} vs. controls [MT 64.9% (95% CI: 59.4-70.3) (P = 0.028); picrosirius red 60.1% (95% CI: 55.4-64.8), (P = 0.029)]. Greater phosphorylated myosin light chain antibody-positive staining in vascular smooth muscle cells was observed in COVID-19 arteries (40.1%; 95% CI: 30.9-49.3) vs. controls (10.0%; 95% CI: 4.4-15.6) (P < 0.001). In proof-of-concept studies, gene pathways associated with extracellular matrix alteration, proteoglycan synthesis, and viral mRNA replication appeared to be upregulated. CONCLUSION: Patients with post-COVID-19 conditions have enhanced vascular fibrosis and myosin light change phosphorylation. Rho-kinase activation represents a novel therapeutic target for clinical trials.


Assuntos
COVID-19 , Doenças Cardiovasculares , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Quinases Associadas a rho/metabolismo , Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico/farmacologia , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/tratamento farmacológico , Síndrome de COVID-19 Pós-Aguda
9.
Chin Clin Oncol ; 12(2): 18, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37081709

RESUMO

A vital constituent of innate immunity, neutrophils had previously been considered functionally rigid with a fixed, defined role in host pathogen response, in part due to their fleeting lifespan. However, that consensus opinion has changed with evidence of functional neutrophil plasticity in a range of diseases including cancer. Typically difficult to sequence due to their low level of transcriptomic activity, advances in single cell RNA sequencing has allowed for closer examination of the neutrophil transcriptome in humans and mouse models and their interaction with other immune system constituents, both in health and disease, allowing for description of neutrophil phenotypes beyond previous descriptions reliant upon microscopic appearance, surface marker expression, and function. Transcriptomic analysis shows that neutrophils develop and mature along a fixed trajectory, but their transcriptome varies based on maturity, the insult that has provoked release from the bone marrow, and the tissue to which they are recruited. Thus neutrophil heterogeneity increases with maturity, with immature neutrophils being more transcriptomically rigid. Here, we review work done in neutrophil single cell RNA sequencing in mice and humans in health and a range of disease states including coronavirus disease 2019 (COVID-19) infection, and solid cancers to provide a template for understanding neutrophil biology in context.


Assuntos
COVID-19 , Neoplasias , Humanos , Animais , Camundongos , Neutrófilos/metabolismo , Imunidade Inata , Neoplasias/genética , Fenótipo
10.
Cancer Res ; 83(8): 1329-1344, 2023 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-37057593

RESUMO

Strong immune responses in primary colorectal cancer correspond with better patient survival following surgery compared with tumors with predominantly stromal microenvironments. However, biomarkers to identify patients with colorectal cancer liver metastases (CRLM) with good prognosis following surgery for oligometastatic disease remain elusive. The aim of this study was to determine the practical application of a simple histological assessment of immune cell infiltration and stromal content in predicting outcome following synchronous resection of primary colorectal cancer and CRLM and to interrogate the underlying functional biology that drives disease progression. Samples from patients undergoing synchronous resection of primary colorectal cancer and CRLM were evaluated in detail through histological assessment, panel genomic and bulk transcriptomic assessment, IHC, and GeoMx spatial transcriptomics (ST) analysis. High immune infiltration of metastases was associated with improved cancer-specific survival. Bulk transcriptomic analysis was confounded by stromal content, but ST demonstrated that the invasive edge of the metastases of long-term survivors was characterized by adaptive immune cell populations enriched for type II IFN signaling and MHC-class II antigen presentation. In contrast, patients with poor prognosis demonstrated increased abundance of regulatory T cells and neutrophils with enrichment of Notch and TGFß signaling pathways at the metastatic tumor center. In summary, histological assessment can stratify outcomes in patients undergoing synchronous resection of CRLM, suggesting that it has potential as a prognostic biomarker. Furthermore, ST analysis has revealed significant intratumoral and interlesional heterogeneity and identified the underlying transcriptomic programs driving each phenotype. SIGNIFICANCE: Spatial transcriptomics uncovers heterogeneity between patients, between matched lesions in the same patient, and within individual lesions and identifies drivers of metastatic progression in colorectal cancer with reactive and suppressed immune microenvironments.


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas , Humanos , Prognóstico , Transcriptoma , Hepatectomia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/secundário , Neoplasias Colorretais/genética , Neoplasias Colorretais/cirurgia , Neoplasias Colorretais/patologia , Microambiente Tumoral/genética
11.
J Immunother Cancer ; 11(1)2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36720497

RESUMO

BACKGROUND: Cancer of unknown primary (CUP) is a heterogeneous group of metastatic cancers where a primary tissue of origin (TOO) is uncertain. Most patients with CUP have limited treatment options and poor survival outcomes. Immune checkpoint inhibitors (ICIs) can be efficacious in some patients with CUP, but the optimal predictive biomarkers are unknown. We therefore assessed immune and genomic biomarkers as well as predicted TOO in patients with CUP, including a subset treated with ICIs. METHODS: Patients with CUP were subject to gene-expression profiling (GEP) and DNA panel sequencing. Immune and stromal-related gene expression was explored by NanoString, including genes associated with immunotherapy response (IR) in other solid malignancies. ICI responsive cancer types were assigned based on Food and Drug Administration-approved indications, and either detection of a latent primary tumor or the TOO was suspected based on genomics informed pathology review. Tumor mutation burden (TMB) and gene mutations were also assessed. RESULTS: A total of 219 patients with CUP were included, 215 assessed for TOO in a previous study, with the majority (163) receiving both RNA and DNA tests. Of GEP profiled cases, 33% (59/175) had a high IR gene-expression score. Of the DNA sequenced cases, 16% (32/203) had high TMB (>10 mutations/Mb), including two with mismatch repair deficiency. Low correlation was observed between TMB and an IR score (R=0.26, p<0.001). Among 110 CUPs with a latent primary or suspected TOO, 47% (52/110) belonged to ICI-responsive cancer types. More than half of the CUPs had at least one feature that may predict ICI response (high IR score, high TMB, ICI-responsive cancer type). Among patients with CUP treated with ICIs, 8/28 (29%) responded (2 complete responses and 6 partial responses). Among non-responders, 9 had stable and 11 had progressive disease. All responders had a high IR score (7/8) and/or high TMB (3/8), while most (5/8) belonged to ICI-responsive cancer types. These features were detected at a lower frequency in non-responders and mostly in patients with stable disease. CONCLUSIONS: A significant fraction of CUP tumors had genomic features previously associated with ICI response. High IR score was the most sensitive predictive feature of ICI response, warranting evaluation in a larger patient series.


Assuntos
Neoplasias Primárias Desconhecidas , Estados Unidos , Humanos , Neoplasias Primárias Desconhecidas/tratamento farmacológico , Neoplasias Primárias Desconhecidas/genética , Mutação , Biomarcadores Tumorais/genética , Imunoterapia , Genômica
12.
J Pathol ; 259(1): 81-92, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36287571

RESUMO

Cancer of unknown primary (CUP) is a syndrome defined by clinical absence of a primary cancer after standardised investigations. Gene expression profiling (GEP) and DNA sequencing have been used to predict primary tissue of origin (TOO) in CUP and find molecularly guided treatments; however, a detailed comparison of the diagnostic yield from these two tests has not been described. Here, we compared the diagnostic utility of RNA and DNA tests in 215 CUP patients (82% received both tests) in a prospective Australian study. Based on retrospective assessment of clinicopathological data, 77% (166/215) of CUPs had insufficient evidence to support TOO diagnosis (clinicopathology unresolved). The remainder had either a latent primary diagnosis (10%) or clinicopathological evidence to support a likely TOO diagnosis (13%) (clinicopathology resolved). We applied a microarray (CUPGuide) or custom NanoString 18-class GEP test to 191 CUPs with an accuracy of 91.5% in known metastatic cancers for high-medium confidence predictions. Classification performance was similar in clinicopathology-resolved CUPs - 80% had high-medium predictions and 94% were concordant with pathology. Notably, only 56% of the clinicopathology-unresolved CUPs had high-medium confidence GEP predictions. Diagnostic DNA features were interrogated in 201 CUP tumours guided by the cancer type specificity of mutations observed across 22 cancer types from the AACR Project GENIE database (77,058 tumours) as well as mutational signatures (e.g. smoking). Among the clinicopathology-unresolved CUPs, mutations and mutational signatures provided additional diagnostic evidence in 31% of cases. GEP classification was useful in only 13% of cases and oncoviral detection in 4%. Among CUPs where genomics informed TOO, lung and biliary cancers were the most frequently identified types, while kidney tumours were another identifiable subset. In conclusion, DNA and RNA profiling supported an unconfirmed TOO diagnosis in one-third of CUPs otherwise unresolved by clinicopathology assessment alone. DNA mutation profiling was the more diagnostically informative assay. © 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.


Assuntos
Neoplasias Primárias Desconhecidas , Humanos , Neoplasias Primárias Desconhecidas/diagnóstico , Neoplasias Primárias Desconhecidas/genética , Neoplasias Primárias Desconhecidas/patologia , Estudos Prospectivos , Estudos Retrospectivos , Austrália , Perfilação da Expressão Gênica , Análise de Sequência de DNA , RNA
13.
Clin Cancer Res ; 28(18): 4056-4069, 2022 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-35792866

RESUMO

PURPOSE: Precise mechanism-based gene expression signatures (GES) have been developed in appropriate in vitro and in vivo model systems, to identify important cancer-related signaling processes. However, some GESs originally developed to represent specific disease processes, primarily with an epithelial cell focus, are being applied to heterogeneous tumor samples where the expression of the genes in the signature may no longer be epithelial-specific. Therefore, unknowingly, even small changes in tumor stroma percentage can directly influence GESs, undermining the intended mechanistic signaling. EXPERIMENTAL DESIGN: Using colorectal cancer as an exemplar, we deployed numerous orthogonal profiling methodologies, including laser capture microdissection, flow cytometry, bulk and multiregional biopsy clinical samples, single-cell RNA sequencing and finally spatial transcriptomics, to perform a comprehensive assessment of the potential for the most widely used GESs to be influenced, or confounded, by stromal content in tumor tissue. To complement this work, we generated a freely-available resource, ConfoundR; https://confoundr.qub.ac.uk/, that enables users to test the extent of stromal influence on an unlimited number of the genes/signatures simultaneously across colorectal, breast, pancreatic, ovarian and prostate cancer datasets. RESULTS: Findings presented here demonstrate the clear potential for misinterpretation of the meaning of GESs, due to widespread stromal influences, which in-turn can undermine faithful alignment between clinical samples and preclinical data/models, particularly cell lines and organoids, or tumor models not fully recapitulating the stromal and immune microenvironment. CONCLUSIONS: Efforts to faithfully align preclinical models of disease using phenotypically-designed GESs must ensure that the signatures themselves remain representative of the same biology when applied to clinical samples.


Assuntos
Neoplasias Ovarianas , Neoplasias da Próstata , Feminino , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Neoplasias Ovarianas/patologia , Neoplasias da Próstata/patologia , Células Estromais/metabolismo , Transcriptoma , Microambiente Tumoral/genética
14.
J Pet Explor Prod Technol ; 12(3): 589-599, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34660163

RESUMO

One of the major concerns during the production of crude oil especially in tropical waters is the deposition of wax on to the walls of the pipeline. This is due to the low seabed temperatures which can be below the wax appearance temperature (WAT) which leads to wax depositing out through molecular diffusion. Currently, there are many methods to prevent and remedy wax deposition but most of these solutions pose a serious environmental threat and are expensive to produce. Hence, this research investigated the use of an organic and cheaper alternative by utilizing synthetic fatty acid esters such as oleic acid which has shown promising results in reducing the pour point of waxy crude oils. The solution that was used was of palm oil origin, crude palm oil (CPO) and crude palm kernel oil (CPKO) and was subsequently compared with the pour point depressant and wax inhibition efficiency of the current industry used inhibitors utilizing the SETA Pour Point and Cloud Point as well as the cold finger apparatus. It was observed that the palm oil inhibitors were highly effective at 1 wt.% due to the high composition of oleic acid present portraying a similar result to Triethanolamine (TEA) while Ethylene Vinyl Acetate (EVA) performed best at low concentration of 0.1 wt.% but deteriorates significantly as the concentration increases due to the polar end agglomerating among itself.

15.
ACS Appl Mater Interfaces ; 13(33): 39925-39933, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34384219

RESUMO

A novel superhydrophobic/superoleophilic surface has been developed by direct surface condensation of dichloroxylene that results in a controlled coating of hyper-cross-linked polymers. Specifically, the coating was successfully applied to a melamine formaldehyde sponge and optimized by fine-tuning the reaction variables. The resulting hierarchical porous sorbents stabilized by polydimethylsiloxane exhibited an increased surface area, good physiochemical stability, high selectivity, and adsorption capacities for a variety of oils and solvents. The composite can separate oil in water emulsions with ultrahigh separation efficiency >99% over 10 cycles in liter-scale experiments, wherein the highest separation efficiency was as low as 2 ppm even with a short period of filtration, suggesting strong potential for oil/water separation and recovery.

16.
Cancers (Basel) ; 13(14)2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34298779

RESUMO

Metastatic colorectal cancer carries poor prognosis, and current therapeutic regimes convey limited improvements in survival and high rates of detrimental side effects in patients that may not stand to benefit. Immunotherapy has revolutionised cancer treatment by restoring antitumoural mechanisms. However, the efficacy in metastatic colorectal cancer, is limited. A literature search was performed using Pubmed (Medline), Web of Knowledge, and Embase. Search terms included combinations of immunotherapy and metastatic colorectal cancer, primarily focusing on clinical trials in humans. Analysis of these studies included status of MMR/MSS, presence of combination strategies, and disease control rate and median overall survival. Evidence shows that immune checkpoint inhibitors, such as anti-PD1 and anti-PD-L1, show efficacy in less than 10% of patients with microsatellite stable, MMR proficient colorectal cancer. In the small subset of patients with microsatellite unstable, MMR deficient cancers, response rates were 40-50%. Combination strategies with immunotherapy are under investigation but have not yet restored antitumoural mechanisms to permit durable disease regression. Immunotherapy provides the potential to offer additional strategies to established chemotherapeutic regimes in metastatic colorectal cancer. Further research needs to establish which adjuncts to immune checkpoint inhibition can unpick resistance, and better predict which patients are likely to respond to individualised therapies to not just improve response rates but to temper unwarranted side effects.

17.
Intern Med J ; 51(2): 280-283, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33631863

RESUMO

There are currently limited Australian data on the outcomes of autologous stem cell transplantation (ASCT) in elderly multiple myeloma (MM) patients. We present the largest cohort of elderly MM patients aged ≥65 years undergoing ASCT in Australia and report their outcomes based on our two-centre experience. Our study affirms that ASCT is well tolerated, safe and effective in elderly MM patients aged ≥65 years and should be considered an important component of treatment in patients who are fit enough for the procedure.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Mieloma Múltiplo , Idoso , Austrália/epidemiologia , Humanos , Mieloma Múltiplo/epidemiologia , Mieloma Múltiplo/terapia , Estudos Retrospectivos , Transplante de Células-Tronco , Transplante Autólogo , Resultado do Tratamento
18.
Surg Endosc ; 35(8): 4192-4199, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-32860135

RESUMO

AIMS: The rate of acute laparoscopic cholecystectomy remains low due to operational constraints. The purpose of this study is to evaluate a service model of index admission cholecystectomy with referral protocols, refined logistics and targeted job planning. METHODS: A prospectively maintained dataset was evaluated to determine the processes of care and outcomes of patients undergoing emergency biliary surgery. The lead author has maintained a 28 years prospective database capturing standard demographic data, intraoperative details including the difficulty of cholecystectomy as well as postoperative outcome parameters and follow up data. RESULTS: Over five thousand (5555) consecutive laparoscopic cholecystectomies were performed. Only patients undergoing emergency procedures (2399,43.2% of entire group) were analysed for this study. The median age was 52 years with 70% being female. The majority were admitted with biliary pain (34%), obstructive jaundice (26%) and acute cholecystitis (16%). 63% were referred by other surgeons. 80% underwent surgery within 5 days (40% within 24 h). Cholecystectomies were performed on scheduled lists (44%) or dedicated emergency lists (29%). Two thirds had suspected bile duct stones and 38.1% underwent bile duct exploration. The median operating time was 75 min, median hospital stay 7 days, conversion rate 0.8%, morbidity 8.9% and mortality rate 0.2%. CONCLUSION: Index admission cholecystectomy for biliary emergencies can have low rates of morbidity and mortality. Timely referral and flexible theatre lists facilitate the service, optimising clinical results, number of biliary episodes, hospital stay and presentation to resolution intervals. Cost benefits and reduced interval readmissions need to be weighed against the length of hospital stay per episode.


Assuntos
Colecistectomia Laparoscópica , Colecistite Aguda , Ductos Biliares , Colecistectomia , Colecistectomia Laparoscópica/efeitos adversos , Colecistite Aguda/cirurgia , Emergências , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade
19.
ACS Omega ; 5(31): 19342-19349, 2020 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-32803027

RESUMO

The ever-increasing demand for the finite source of oil has led oil production companies to produce and transport the produced crude oil as efficiently and economically as possible. One of the major concerns especially in waters like the South China Sea is the deposition of wax on the walls of the pipeline or wellbore, constricting and hindering the hydrocarbon flow. This is due to the low seabed temperatures, which can be below the wax appearance temperature (WAT), leading to the deposition of wax out of waxy crude oil through the molecular dispersion mechanism. Currently, many prevention and remedy methods are in place to overcome the problem, but most of the additives possess environmental threat, as most of the chemical solutions used are toxic, nonorganic, and costly. Hence, this paper aims to provide some insights into the effect of palm oil derivatives such as crude palm oil (CPO) and crude palm kernel oil (CPKO) on wax inhibition. The effect of aging time (i.e., immersion time) was also evaluated. A comparison was made between paraffin inhibition efficiency results (PIE %) obtained by CPO, CPKO, poly(ethylene-co-vinyl acetate) (EVA), and triethanolamine (TEA). It was observed that the average efficiency of 81.67% was obtained when 1% CPO was added to heavy crude oil. The wax inhibition performance reached a plateau after 1.5 h of aging time for all of the investigated samples.

20.
ACS Appl Mater Interfaces ; 11(6): 6502-6511, 2019 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-30653301

RESUMO

Membranes are particularly attractive for lowering the energy intensity of separations as they eliminate phase changes. While many tantalizing polymers are known, limitations in selectivity and stability slightly preclude further development. Mixed-matrix membranes may address these shortcomings. Key to their realization is the intimate mixing between the polymer and the additive to eliminate nonselective transport, improve selectivity, and resist physical aging. Polymers of intrinsic microporosity (PIMs) have inherently promising gas transport properties. Here, we show that porous additives can improve transport and resist aging in PIM-1. We develop a simple, low-cost, and scalable hyper-cross-linked polymer (poly-dichloroxylene, pDCX), which was hydroxylated to form an intimate mixture with the polar PIM-1. Solvent variation allowed control of physical aging rates and improved selectivity for smaller gases. This detailed study has allowed many interactions within mixed matrix membranes to be directly elucidated and presents a practical means to stabilize porous polymers for separation applications.

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