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1.
PLoS One ; 19(4): e0300357, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38630774

RESUMO

BACKGROUND: We investigated the impact of the COVID-19 pandemic on trends of presentation, management and pathology findings in patients who underwent an appendicectomy for suspected acute appendicitis. METHOD: The retrospective study reviewed patients (n = 939 adults and n = 329 children) who had an appendicectomy performed for suspected acute appendicitis and histopathology assessment in the Belfast Health and Social Care Trust, Northern Ireland. Pre-COVID-19 (March 2019 to February 2020) and COVID-19 Year 1 (March 2020 to February 2021) data were compared. Chi-squared tests were applied to compare timeframes. RESULTS: 513 adult appendicectomies were performed in the immediate year pre-COVID-19, compared to 426 in COVID-19 Year 1, representing a 17% reduction. No such reduction was seen within the paediatric population, likely related to a change in regional paediatric referral criteria during the pandemic. When comparing COVID-19 Year 1 with pre-pandemic, fewer patients presented with <24 hours of symptoms (45% v 53%, p = 0.005), and there was greater use of pre-operative computed tomography imaging in adults (63.2% v 48.7%, p<0.001). Fewer adult and paediatric cases of simple acute appendicitis and non-diagnostic specimens, with relative increased proportions of perforated acute appendicitis, were observed in COVID-19 Year 1 compared with pre-pandemic. No absolute increase in perforated acute appendicitis cases was observed in adults. CONCLUSION: Year 1 of the COVID-19 pandemic was associated with delayed presentation of acute appendicitis in adults and children. In adults, an overall reduction in appendicectomy operations, increased use of pre-operative diagnostic imaging, and fewer specimens showing simple acute appendicitis or non-diagnostic features, collectively support appropriate restriction of surgery for those patients with a more certain acute appendicitis diagnosis.


Assuntos
Apendicite , COVID-19 , Adulto , Humanos , Criança , Apendicite/cirurgia , Estudos Retrospectivos , Pandemias , COVID-19/epidemiologia , Apendicectomia , Doença Aguda
2.
Int J Mol Sci ; 25(8)2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38673839

RESUMO

Phagocytosis (and endocytosis) is an unusual cellular process that results in the formation of a novel subcellular organelle, the phagosome. This phagosome contains not only the internalised target of phagocytosis but also the external medium, creating a new border between extracellular and intracellular environments. The boundary at the plasma membrane is, of course, tightly controlled and exploited in ionic cell signalling events. Although there has been much work on the control of phagocytosis by ions, notably, Ca2+ ions influxing across the plasma membrane, increasing our understanding of the mechanism enormously, very little work has been done exploring the phagosome/cytosol boundary. In this paper, we explored the changes in the intra-phagosomal Ca2+ ion content that occur during phagocytosis and phagosome formation in human neutrophils. Measuring Ca2+ ion concentration in the phagosome is potentially prone to artefacts as the intra-phagosomal environment experiences changes in pH and oxidation. However, by excluding such artefacts, we conclude that there are open Ca2+ channels on the phagosome that allow Ca2+ ions to "drain" into the surrounding cytosol. This conclusion was confirmed by monitoring the translocation of the intracellularly expressed YFP-tagged C2 domain of PKC-γ. This approach marked regions of membrane at which Ca2+ influx occurred, the earliest being the phagocytic cup, and then the whole cell. This paper therefore presents data that have novel implications for understanding phagocytic Ca2+ signalling events, such as peri-phagosomal Ca2+ hotspots, and other phenomena.


Assuntos
Sinalização do Cálcio , Cálcio , Neutrófilos , Fagocitose , Fagossomos , Humanos , Cálcio/metabolismo , Fagossomos/metabolismo , Neutrófilos/metabolismo , Citosol/metabolismo , Membrana Celular/metabolismo
4.
Nat Genet ; 56(3): 458-472, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38351382

RESUMO

Molecular stratification using gene-level transcriptional data has identified subtypes with distinctive genotypic and phenotypic traits, as exemplified by the consensus molecular subtypes (CMS) in colorectal cancer (CRC). Here, rather than gene-level data, we make use of gene ontology and biological activation state information for initial molecular class discovery. In doing so, we defined three pathway-derived subtypes (PDS) in CRC: PDS1 tumors, which are canonical/LGR5+ stem-rich, highly proliferative and display good prognosis; PDS2 tumors, which are regenerative/ANXA1+ stem-rich, with elevated stromal and immune tumor microenvironmental lineages; and PDS3 tumors, which represent a previously overlooked slow-cycling subset of tumors within CMS2 with reduced stem populations and increased differentiated lineages, particularly enterocytes and enteroendocrine cells, yet display the worst prognosis in locally advanced disease. These PDS3 phenotypic traits are evident across numerous bulk and single-cell datasets, and demark a series of subtle biological states that are currently under-represented in pre-clinical models and are not identified using existing subtyping classifiers.


Assuntos
Neoplasias Colorretais , Humanos , Neoplasias Colorretais/patologia , Prognóstico , Diferenciação Celular/genética , Fenótipo , Biomarcadores Tumorais/genética , Perfilação da Expressão Gênica
5.
Histopathology ; 84(5): 847-862, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38233108

RESUMO

AIMS: To conduct a definitive multicentre comparison of digital pathology (DP) with light microscopy (LM) for reporting histopathology slides including breast and bowel cancer screening samples. METHODS: A total of 2024 cases (608 breast, 607 GI, 609 skin, 200 renal) were studied, including 207 breast and 250 bowel cancer screening samples. Cases were examined by four pathologists (16 study pathologists across the four speciality groups), using both LM and DP, with the order randomly assigned and 6 weeks between viewings. Reports were compared for clinical management concordance (CMC), meaning identical diagnoses plus differences which do not affect patient management. Percentage CMCs were computed using logistic regression models with crossed random-effects terms for case and pathologist. The obtained percentage CMCs were referenced to 98.3% calculated from previous studies. RESULTS: For all cases LM versus DP comparisons showed the CMC rates were 99.95% [95% confidence interval (CI) = 99.90-99.97] and 98.96 (95% CI = 98.42-99.32) for cancer screening samples. In speciality groups CMC for LM versus DP showed: breast 99.40% (99.06-99.62) overall and 96.27% (94.63-97.43) for cancer screening samples; [gastrointestinal (GI) = 99.96% (99.89-99.99)] overall and 99.93% (99.68-99.98) for bowel cancer screening samples; skin 99.99% (99.92-100.0); renal 99.99% (99.57-100.0). Analysis of clinically significant differences revealed discrepancies in areas where interobserver variability is known to be high, in reads performed with both modalities and without apparent trends to either. CONCLUSIONS: Comparing LM and DP CMC, overall rates exceed the reference 98.3%, providing compelling evidence that pathologists provide equivalent results for both routine and cancer screening samples irrespective of the modality used.


Assuntos
Neoplasias da Mama , Neoplasias Colorretais , Patologia Clínica , Humanos , Detecção Precoce de Câncer , Interpretação de Imagem Assistida por Computador/métodos , Microscopia/métodos , Patologia Clínica/métodos , Feminino , Estudos Multicêntricos como Assunto
6.
Metabolites ; 14(1)2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38248836

RESUMO

Type 2 diabetes mellitus (T2DM) poses a higher risk for complications in South Asian individuals compared to other ethnic groups. To shed light on potential mediating factors, we investigated lipidomic changes in plasma of Dutch South Asians (DSA) and Dutch white Caucasians (DwC) with and without T2DM and explore their associations with clinical features. Using a targeted quantitative lipidomics platform, monitoring over 1000 lipids across 17 classes, along with 1H NMR based lipoprotein analysis, we studied 51 healthy participants (21 DSA, 30 DwC) and 92 T2DM patients (47 DSA, 45 DwC) from the MAGNetic resonance Assessment of VICTOza efficacy in the Regression of cardiovascular dysfunction in type 2 dIAbetes mellitus (MAGNA VICTORIA) study. This comprehensive mapping of the circulating lipidome allowed us to identify relevant lipid modules through unbiased weighted correlation network analysis, as well as disease and ethnicity related key mediatory lipids. Significant differences in lipidomic profiles, encompassing various lipid classes and species, were observed between T2DM patients and healthy controls in both the DSA and DwC populations. Our analyses revealed that healthy DSA, but not DwC, controls already exhibited a lipid profile prone to develop T2DM. Particularly, in DSA-T2DM patients, specific lipid changes correlated with clinical features, particularly diacylglycerols (DGs), showing significant associations with glycemic control and renal function. Our findings highlight an ethnic distinction in lipid modules influencing clinical outcomes in renal health. We discover distinctive ethnic disparities of the circulating lipidome and identify ethnicity-specific lipid markers. Jointly, our discoveries show great potential as personalized biomarkers for the assessment of glycemic control and renal function in DSA-T2DM individuals.

7.
Gastroenterol Clin North Am ; 53(1): 201-220, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38280748

RESUMO

Anal cancer, mainly squamous cell carcinoma, is rare but increasing in prevalence, as is its precursor lesion, anal squamous dysplasia. They are both strongly associated with human papillomavirus infection. The 2-tiered Lower Anogenital Squamous Terminology classification, low-grade SIL and high-grade SIL, is preferred to the 3-tiered anal intraepithelial neoplasia classification because of better interobserver agreement and clearer management implications. Immunohistochemistry with p16 is helpful to corroborate the diagnosis of squamous dysplasia. Similarly, immunohistochemistry is helpful to differentiate primary Paget disease from secondary Paget disease, which is usually due to anal squamous mucosal/epidermal involvement by primary rectal adenocarcinoma.


Assuntos
Neoplasias do Ânus , Carcinoma in Situ , Carcinoma de Células Escamosas , Infecções por Papillomavirus , Humanos , Imuno-Histoquímica , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/patologia , Canal Anal , Carcinoma in Situ/diagnóstico , Carcinoma in Situ/patologia , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/diagnóstico , Neoplasias do Ânus/diagnóstico , Neoplasias do Ânus/patologia
8.
J Crohns Colitis ; 18(2): 175-191, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-37607017

RESUMO

Histological assessment of endoscopic biopsies in inflammatory bowel disease [IBD] plays an important role in clinical management, investigative studies, and clinical trials. Scoring schemes consisting of multiple histological items and offering considerable precision are widely available. However, definitions of histological abnormalities are often inconsistent. Furthermore, interobserver variability for their recognition and assessment may be high. The European Crohn's and Colitis Organisation [ECCO] formed an expert panel to explore definitions of histological abnormalities in IBD, with the aim of improving the quality of diagnosis and facilitating development of scoring schemes. The process confirmed that the current definitions often have no evidence base and vary between sources. Using available evidence and expert knowledge, the panel produced a series of ECCO consensus position statements on histological features in IBD.


Assuntos
Colite Ulcerativa , Doença de Crohn , Doenças Inflamatórias Intestinais , Humanos , Colite Ulcerativa/tratamento farmacológico , Doenças Inflamatórias Intestinais/diagnóstico , Doenças Inflamatórias Intestinais/patologia , Doença de Crohn/tratamento farmacológico
9.
Mod Pathol ; 37(3): 100419, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38158125

RESUMO

Due to their increased cancer risk, patients with longstanding inflammatory bowel disease are offered endoscopic surveillance with concomitant histopathologic assessments, aimed at identifying dysplasia as a precursor lesion of colitis-associated colorectal cancer. However, this strategy is beset with difficulties and limitations. Recently, a novel classification criterion for colitis-associated low-grade dysplasia has been proposed, and an association between nonconventional dysplasia and progression was reported, suggesting the possibility of histology-based stratification of patients with colitis-associated lesions. Here, a cohort of colitis-associated lesions was assessed by a panel of 6 experienced pathologists to test the applicability of the published classification criteria and try and validate the association between nonconventional dysplasia and progression. While confirming the presence of different morphologic patterns of colitis-associated dysplasia, the study demonstrated difficulties concerning diagnostic reproducibility between pathologists and was unable to validate the association of nonconventional dysplasia with cancer progression. Our study highlights the overall difficulty of using histologic assessment of precursor lesions for cancer risk prediction in inflammatory bowel disease patients and suggests the need for a different diagnostic strategy that can objectively identify high-risk phenotypes.


Assuntos
Colite Ulcerativa , Colite , Neoplasias Colorretais , Doenças Inflamatórias Intestinais , Neoplasias , Humanos , Reprodutibilidade dos Testes , Colite/complicações , Doenças Inflamatórias Intestinais/complicações , Doenças Inflamatórias Intestinais/diagnóstico , Doenças Inflamatórias Intestinais/patologia , Colonoscopia , Hiperplasia , Neoplasias Colorretais/patologia , Colite Ulcerativa/complicações , Colite Ulcerativa/diagnóstico , Colite Ulcerativa/patologia
10.
Am J Surg Pathol ; 48(4): 465-474, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38155543

RESUMO

Colorectal carcinoma with sarcomatoid components (which includes so-called carcinosarcomas and sarcomatoid carcinomas) is a rare subtype with 50 reported cases in the literature and overlapping criteria with undifferentiated carcinoma. We collected and described 15 cases from 10 men and 5 women, with a mean age of 66 years. Symptoms included abdominal pain and gastrointestinal bleeding. Most tumors presented in the rectosigmoid region, with a mean size of 8.2 cm. The sarcomatoid component, on average, represented 58% of the tumors and took many forms, including spindled (10 cases), anaplastic (9 cases), and rhabdoid (3 cases); one case showed osteoid matrix. Tumor budding was usually high, and tumor-infiltrating lymphocytes were usually low. The sarcomatoid component was keratin-positive in 10 cases. One case showed loss of mismatch repair protein expression, and 2 cases showed SMARCA4 loss (1 also with SMARCA2 loss). Molecular testing identified mutations in KRAS (n=1), NRAS (n=2), BRAF (n=2), APC (n=1), and TP53 (n=1) in a few cases. Tumors often presented at advanced stage, with 11 cases pT4, 9 cases with nodal metastases, and 7 cases with distant metastases. Follow-up was available for 10 cases (median: 2 months), with 2 alive without disease, 3 alive with disease, and 5 dead. Our findings roughly corresponded with those in previously reported cases. Colorectal carcinoma with sarcomatoid components is rare and aggressive, with a poor prognosis for many patients. We suggest that spindled cells, anaplasia, heterologous elements, and/or a component with definable sarcomatous lineage be used to distinguish colorectal carcinoma with sarcomatoid components from undifferentiated carcinoma.


Assuntos
Carcinoma , Carcinossarcoma , Neoplasias Colorretais , Sarcoma , Masculino , Humanos , Feminino , Idoso , Carcinoma/patologia , Sarcoma/patologia , Neoplasias Colorretais/genética , DNA Helicases , Proteínas Nucleares , Fatores de Transcrição
11.
Comput Struct Biotechnol J ; 23: 174-185, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38146436

RESUMO

The immune response associated with oncogenesis and potential oncological ther- apeutic interventions has dominated the field of cancer research over the last decade. T-cell lymphocytes in the tumor microenvironment are a crucial aspect of cancer's adaptive immunity, and the quantification of T-cells in specific can- cer types has been suggested as a potential diagnostic aid. However, this is cur- rently not part of routine diagnostics. To address this challenge, we present a new method called True-T, which employs artificial intelligence-based techniques to quantify T-cells in colorectal cancer (CRC) using immunohistochemistry (IHC) images. True-T analyses the chromogenic tissue hybridization signal of three widely recognized T-cell markers (CD3, CD4, and CD8). Our method employs a pipeline consisting of three stages: T-cell segmentation, density estimation from the segmented mask, and prediction of individual five-year survival rates. In the first stage, we utilize the U-Net method, where a pre-trained ResNet-34 is em- ployed as an encoder to extract clinically relevant T-cell features. The segmenta- tion model is trained and evaluated individually, demonstrating its generalization in detecting the CD3, CD4, and CD8 biomarkers in IHC images. In the second stage, the density of T-cells is estimated using the predicted mask, which serves as a crucial indicator for patient survival statistics in the third stage. This ap- proach was developed and tested in 1041 patients from four reference diagnostic institutions, ensuring broad applicability. The clinical effectiveness of True-T is demonstrated in stages II-IV CRC by offering valuable prognostic information that surpasses previous quantitative gold standards, opening possibilities for po- tential clinical applications. Finally, to evaluate the robustness and broader ap- plicability of our approach without additional training, we assessed the universal accuracy of the CD3 component of the True-T algorithm across 13 distinct solid tumors.

12.
Med Image Anal ; 92: 103059, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38104402

RESUMO

Artificial intelligence (AI) has a multitude of applications in cancer research and oncology. However, the training of AI systems is impeded by the limited availability of large datasets due to data protection requirements and other regulatory obstacles. Federated and swarm learning represent possible solutions to this problem by collaboratively training AI models while avoiding data transfer. However, in these decentralized methods, weight updates are still transferred to the aggregation server for merging the models. This leaves the possibility for a breach of data privacy, for example by model inversion or membership inference attacks by untrusted servers. Somewhat-homomorphically-encrypted federated learning (SHEFL) is a solution to this problem because only encrypted weights are transferred, and model updates are performed in the encrypted space. Here, we demonstrate the first successful implementation of SHEFL in a range of clinically relevant tasks in cancer image analysis on multicentric datasets in radiology and histopathology. We show that SHEFL enables the training of AI models which outperform locally trained models and perform on par with models which are centrally trained. In the future, SHEFL can enable multiple institutions to co-train AI models without forsaking data governance and without ever transmitting any decryptable data to untrusted servers.


Assuntos
Neoplasias , Radiologia , Humanos , Inteligência Artificial , Aprendizagem , Neoplasias/diagnóstico por imagem , Processamento de Imagem Assistida por Computador
13.
J Magn Reson Imaging ; 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38085104

RESUMO

BACKGROUND: Ethnic differences in the progression and outcome of diabetic kidney disease (DKD) remain to be elucidated. MRI-quantified renal sinus fat volume could be a potential biomarker to help investigate the changes of DKD risk in response to glucose regulation. PURPOSE: To evaluate whether the effect of glucose-lowering treatment on renal sinus fat volume differed in West Europeans (WE) compared to South Asians (SA), and whether ethnic-related difference exists regarding the effect of liraglutide on renal sinus fat. STUDY TYPE: Retrospective. POPULATION: Ninety-three patients with type 2 diabetes mellitus, including 47 WE (27 males) aged 59.3 ± 6.5 years, and 46 SA (19 males) aged 54.4 ± 9.8 years. FIELD STRENGTH/SEQUENCE: 3.0 T dual-echo fast gradient-echo pulse sequence using two-point Dixon technique with a phase-correction algorithm. ASSESSMENT: Changes of renal sinus fat volume were measured by a radiologist (LL) with 4-years' experience, and were compared between the two ethnic groups, together with glycemic level, metabolic risk factors and renal function. The effects of liraglutide were assessed. STATISTICAL TESTS: Normality of the data was visually evaluated by histograms and Q-Q plots. Within-group and between-group differences were analyzed using paired t-tests and analysis of covariance. Associations were analyzed by person's correlation and multiple linear regression models. RESULTS: Renal sinus fat decreased in SA patients (Δ% = -7.6% ± 14.8%), but increased in WE patients (Δ% = 5.0% ± 13.1%), with a significant difference between the two ethnic groups. In the WE group, the increase of sinus fat volume was significant in the placebo subgroup (Δ% = 6.8% ± 12.5%), in contrast to the nonsignificant increase in the liraglutide subgroup (Δ% = 3.0% ± 13.8%, P = 0.444). DATA CONCLUSION: Renal sinus fat accumulation responds differently to glucose regulation, showing a reduction in SA patients in contrast to a persistent accumulation in WE patients. A trend of less accumulation of sinus fat in WE patients receiving liraglutide has been observed. EVIDENCE LEVEL: 4 TECHNICAL EFFICACY: Stage 4.

14.
J Pathol ; 261(2): 121-124, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37565277

RESUMO

Tumour budding (TB) describes single or small groups of neoplastic cells that lack continuity with an advancing tumour front. Poorly differentiated clusters (PDCs) are larger and qualitatively different. TB grade and PDCs may predict a worse outcome in colorectal carcinoma and other cancers and fall into the category of 'invasive front prognostic markers' that also includes intratumoural stroma type. Epithelial-mesenchymal transition (EMT) allows the adoption by epithelial cells of mesenchymal characteristics such as dyscohesion, migration, and stromal invasion. TB and PDCs harbor alterations in EMT-related proteins and RNAs and may be morphological manifestations of EMT. However, persistence of epithelioid features and absence of a full complement of typical alterations in TB and PDCs may indicate 'partial EMT', i.e. an intermediate/hybrid state. Recently, Pavlic et al asserted that TB and PDCs in colorectal cancer represent different manifestations of partial EMT and, perhaps controversially, that TB is closer than PDCs to complete transition. In clinical practice, low inter-observer agreement for invasive front prognostic markers is a potential problem. The UK colorectal cancer pathology dataset advises assessment of TB and recommends the use of an international consensus system, but time will tell if we are adopting reliable prognostic markers or reinventing the wheel. Additional studies of TB, PDCs, and EMT will presumably allow greater insight into their role in tumour development and progression. © 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 , Transição Epitelial-Mesenquimal , Humanos , Células Epiteliais/patologia , Neoplasias Colorretais/patologia , Reino Unido , Prognóstico
15.
Histopathology ; 83(5): 756-770, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37565291

RESUMO

AIMS: We report pathology findings from the first 10 years of the faecal-occult blood-based Northern Ireland Bowel Cancer Screening Programme, presenting summary data and trends in pathology diagnoses and clinicopathological features of screen-detected cancers. METHODS AND RESULTS: Data were analysed from a comprehensive polyp-level pathology database representing all endoscopy specimens from programme inception in 2010 until 2021. A total of 9800 individuals underwent 13 472 endoscopy procedures, yielding 25 967 pathology specimens and 32 119 diagnoses. Index specimen diagnoses (4.1%) and index colonoscopies (10.4%) yielded a diagnosis of colorectal cancer, representing 1045 cancers from 1020 individuals (25 with synchronous cancers). A further 13 index cancers were identified via computed tomography colonography; 65.3% of cancer diagnoses were in males; 41.7% were stage I, 23.1% stage II, 25.8% stage III and 1.8% stage IV (7.6% unstaged). Of 233 pT1 cancers diagnosed within local excision specimens, 79 (33.9%) had completion surgery. Ten-year trends showed a steady decline in the proportion of index colonoscopies that yielded a diagnosis of cancer (14.7% in year 1; 4.8% in year 11) or advanced colorectal polyp. There was a strong upward trend in diagnoses of sessile serrated lesions, which overtook hyperplastic polyps in proportions of total index diagnoses by the end of the study time-frame (8.7% compared to 8.5%). CONCLUSIONS: Over the first 10 years of a population colorectal cancer screening programme, 'real world' pathology data demonstrate success in the form of reduced diagnoses of cancer and advanced colorectal polyp with passage of successive screening rounds. Interesting trends with respect to serrated polyp diagnoses are also evident, probably related to pathologist and endoscopist behaviour.


Assuntos
Adenoma , Pólipos do Colo , Neoplasias Colorretais , Masculino , Humanos , Pólipos do Colo/diagnóstico , Pólipos do Colo/patologia , Adenoma/patologia , Detecção Precoce de Câncer , Neoplasias Colorretais/patologia , Colonoscopia/métodos
16.
Cancer Cell ; 41(9): 1650-1661.e4, 2023 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-37652006

RESUMO

Deep learning (DL) can accelerate the prediction of prognostic biomarkers from routine pathology slides in colorectal cancer (CRC). However, current approaches rely on convolutional neural networks (CNNs) and have mostly been validated on small patient cohorts. Here, we develop a new transformer-based pipeline for end-to-end biomarker prediction from pathology slides by combining a pre-trained transformer encoder with a transformer network for patch aggregation. Our transformer-based approach substantially improves the performance, generalizability, data efficiency, and interpretability as compared with current state-of-the-art algorithms. After training and evaluating on a large multicenter cohort of over 13,000 patients from 16 colorectal cancer cohorts, we achieve a sensitivity of 0.99 with a negative predictive value of over 0.99 for prediction of microsatellite instability (MSI) on surgical resection specimens. We demonstrate that resection specimen-only training reaches clinical-grade performance on endoscopic biopsy tissue, solving a long-standing diagnostic problem.


Assuntos
Algoritmos , Neoplasias Colorretais , Humanos , Biomarcadores , Biópsia , Instabilidade de Microssatélites , Neoplasias Colorretais/genética
17.
Diabetes Obes Metab ; 25(8): 2374-2387, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37202875

RESUMO

BACKGROUND: Composition of high-density lipoproteins (HDL) is emerging as an important determinant in the development of microvascular complications in type 2 diabetes mellitus (T2DM). Dutch South Asian (DSA) individuals with T2DM display an increased risk of microvascular complications compared with Dutch white Caucasian (DwC) individuals with T2DM. In this study, we aimed to investigate whether changes in HDL composition associate with increased microvascular risk in this ethnic group and lead to new lipoprotein biomarkers. MATERIALS AND METHODS: Using 1 H nuclear magnetic resonance spectroscopy and Bruker IVDr Lipoprotein Subclass Analysis (B.I.LISA) software, plasma lipoprotein changes were determined in 51 healthy individuals (30 DwC, 21 DSA) and 92 individuals with T2DM (45 DwC, 47 DSA) in a cross-sectional, case-control study. Differential HDL subfractions were investigated using multinomial logistic regression analyses, adjusting for possible confounders including BMI and diabetes duration. RESULTS: We identified HDL compositional differences between healthy and diabetic individuals in both ethnic groups. Specifically, levels of apolipoprotein A2 and HDL-4 subfractions were lower in DSA compared with DwC with T2DM. Apolipoprotein A2 and HDL-4 subfractions also negatively correlated with waist circumference, waist-to-hip ratio, haemoglobin A1c, glucose levels and disease duration in DSA with T2DM, and associated with increased incidence of microvascular complications. CONCLUSION: While HDL composition differed between controls and T2DM in both ethnic groups, the lower levels of lipid content in the smallest HDL subclass (HDL-4) in DSA with T2DM appeared to be more clinically relevant, with higher odds of having diabetes-related pan-microvascular complications such as retinopathy and neuropathy. These typical differences in HDL could be used as ethnicity-specific T2DM biomarkers.


Assuntos
Diabetes Mellitus Tipo 2 , Lipoproteínas HDL , Humanos , Estudos Transversais , Estudos de Casos e Controles , Apolipoproteína A-II , Lipoproteínas , Biomarcadores , HDL-Colesterol
18.
Int J Mol Sci ; 24(9)2023 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-37175762

RESUMO

Insulin facilitates renal sodium reabsorption and attenuates gluconeogenesis. Sex differences in this regulation have not been well characterized. Using tetracycline-inducible Cre-lox recombination, we knocked out (KO) the insulin receptor (InsR) from the renal tubule in adult male (M) and female (F) mice (C57Bl6 background) with a paired box 8 (PAX8) promoter. Body weights were not affected by the KO, but mean kidney weights were reduced in the KO mice (13 and 3%, in M and F, respectively, relative to wild-type (WT) mice). A microscopic analysis revealed 25 and 19% reductions in the proximal tubule (PT) and cortical collecting duct cell heights, respectively, in KOMs relative to WTMs. The reductions were 5 and 11% for KOFs. Western blotting of renal cortex homogenates showed decreased protein levels for the ß and γ subunits of the epithelial sodium channel (ENaC) and the sodium-potassium-2-chloride cotransporter type 2 (NKCC2) in both sexes of KO mice; however, α-ENaC was upregulated in KOMs and downregulated in KOFs. Both sexes of KO mice cleared exogenously administered glucose faster than the WT mice and had lower semi-fasted, anesthetized blood glucose levels. However, KOMs (but not KOFs) demonstrated evidence of enhanced renal gluconeogenesis, including higher levels of renal glucose-6-phosphatase, the PT's production of glucose, post-prandial blood glucose, and plasma insulin, whereas KOFs exhibited downregulation of renal high-capacity sodium glucose cotransporter (SGLT2) and upregulation of SGLT1; these changes appeared to be absent in the KOM. Overall, these findings suggest a sex-differential reliance on intact renal tubular InsR signaling which may be translationally important in type 2 diabetes, obesity, or insulin resistance when renal insulin signaling is reduced.


Assuntos
Diabetes Mellitus Tipo 2 , Receptor de Insulina , Feminino , Masculino , Animais , Camundongos , Receptor de Insulina/genética , Receptor de Insulina/metabolismo , Glicemia , Insulina/metabolismo , Glucose/metabolismo , Camundongos Knockout , Sódio/metabolismo , Canais Epiteliais de Sódio/metabolismo
19.
Int J Mol Sci ; 24(3)2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36769146

RESUMO

Phagocytosis is one of the most polarised of all cellular activities. Both the stimulus (the target for phagocytosis) and the response (its internalisation) are focussed at just one part of the cell. At the locus, and this locus alone, pseudopodia form a phagocytic cup around the particle, the cytoskeleton is rearranged, the plasma membrane is reorganised, and a new internal organelle, the phagosome, is formed. The effect of signals from the stimulus must, thus, both be complex and yet be restricted in space and time to enable an effective focussed response. While many aspects of phagocytosis are being uncovered, the mechanism for the restriction of signalling or the effects of signalling remains obscure. In this review, the details of the problem of restricting chemical intracellular signalling are presented, with a focus on diffusion into the cytosol and of signalling lipids along the plasma membrane. The possible ways in which simple diffusion is overcome so that the restriction of signalling and effective phagocytosis can be achieved are discussed in the light of recent advances in imaging, biophysics, and cell biochemistry which together are providing new insights into this area.


Assuntos
Fagocitose , Fagossomos , Fagocitose/fisiologia , Fagossomos/metabolismo , Pseudópodes/metabolismo , Citoesqueleto/metabolismo , Citosol/metabolismo
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