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Histology; Liver; Microstructure Histología; Hígado; Microestructura Histologia; Fetge; Microestructura Purpose Relationships between diffusion-weighted MRI signals and hepatocyte microstructure were investigated to inform liver diffusion MRI modeling, focusing on the following question: Can cell size and diffusivity be estimated at fixed diffusion time, realistic SNR, and negligible contribution from extracellular/extravascular water and exchange? Methods Monte Carlo simulations were performed within synthetic hepatocytes for varying cell size/diffusivity L / D0 , and clinical protocols (single diffusion encoding; maximum b-value: {1000, 1500, 2000} s/mm2; 5 unique gradient duration/separation pairs; SNR = { ∞ , 100, 80, 40, 20}), accounting for heterogeneity in (D0,L) and perfusion contamination. Diffusion ( D ) and kurtosis ( K ) coefficients were calculated, and relationships between (D0,L) and (D,K) were visualized. Functions mapping (D,K) to (D0,L) were computed to predict unseen (D0,L) values, tested for their ability to classify discrete cell-size contrasts, and deployed on 9.4T ex vivo MRI-histology data of fixed mouse livers Results Relationships between (D,K) and (D0,L) are complex and depend on the diffusion encoding. Functions mapping (D,K) to (D0,L) captures salient characteristics of D0(D,K) and L(D,K) dependencies. Mappings are not always accurate, but they enable just under 70% accuracy in a three-class cell-size classification task (for SNR = 20, bmax = 1500 s/mm2, δ = 20 ms, and Δ = 75 ms). MRI detects cell-size contrasts in the mouse livers that are confirmed by histology, but overestimates the largest cell sizes. Conclusion Salient information about liver cell size and diffusivity may be retrieved from minimal diffusion encodings at fixed diffusion time, in experimental conditions and pathological scenarios for which extracellular, extravascular water and exchange are negligible. This project was supported by Fundació La Caixa and by the investigator-initiated PREdICT study at the Vall d'Hebron Institute of Oncology (Barcelona), funded by AstraZeneca and supporting FG. FG has received funding from the postdoctoral fellowships programme Beatriu de Pinós (2020 BP 00117), funded by the Secretary of Universities and Research (Government of Catalonia). KB is funded by a Beatriu de Pinós post-doctoral grant (2019 BP 00182). RPL is supported by a CRIS Foundation Talent Award (TALENT19-05), the Instituto de Salud Carlos III-Investigación en Salud (PI18/01395), Spanish Ministry for Science, Innovation and Universities (RTI2018-095209-B-C21, FIS-G64384969), Prostate Cancer Foundation Young Investigator Award and Fero Foundation. ICS is supported by a fellowship from Fundació ”la Caixa” (ID 100010434) and the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 847648, fellowship code LCF/BQ/PI20/1176003

Assessment of treatment efficacy in metastatic castration-resistant prostate cancer (mCRPC) is limited by frequent nonmeasurable bone metastases. The count of circulating tumor cells (CTCs) is a promising surrogate marker that may replace the widely used prostate-specific antigen (PSA). The purpose of this study was to quantify the dynamic relationships between the longitudinal kinetics of these markers during treatment in patients with mCRPC. Data from 223 patients with mCRPC treated by chemotherapy and/or hormonotherapy were analyzed for up to 6 months of treatment. A semimechanistic model was built, combining the following several pharmacometric advanced features: (1) Kinetic-Pharmacodynamic (K-PD) compartments for treatments (chemotherapy and hormonotherapy); (2) a latent variable linking both marker kinetics; (3) modeling of CTC kinetics with a cell lifespan model; and (4) a negative binomial distribution for the CTC random sampling. Linked with survival, this model would potentially be useful for predicting treatment efficacy during drug development or for therapeutic adjustment in treated patients.

Aim Adjuvant 5-fluorouracil based chemotherapy has demonstrated benefit in Stage III colon cancer but still remains controversial in Stage II. The aim of this study was to analyse the prognostic impact of clinicopathological factors that may help guide treatment decisions in Stage II colon cancer. Method Between 1996 and 2006 data from patients diagnosed with colorectal cancer at Hospital Universitari Bellvitge and its referral comprehensive cancer centre Institut Catala d′Oncologia/L’Hospitalet were prospectively included in a database. We identified 432 patients with Stage II colon cancer operated on at Hospital Universitari Bellvitge. The 5-year relapse-free survival (RFS) and colon-cancer-specific survival (CCSS) were determined. Results The 5-year RFS and CCSS were 83% and 88%, respectively. Lymphovascular or perineural invasion was associated with RFS [hazard ratio (HR) 1.84; 95% CI 1.01–3.35]. Gender (women, HR 0.48; 95% CI 0.23–1) and lymphovascular or perineural invasion (HR 3.51; 95% CI 1.86–6.64) together with pT4 (HR 2.79; 95% CI 1.44–5.41) influenced CCSS. In multivariate analysis pT4 and lymphovascular or perineural invasion remained significantly associated with CCSS. We performed a risk index with these factors with prognostic impact. Patients with pT4 tumours and lymphovascular or perineural invasion had a 5-year CCSS of 61%vs the 93% (HR 5.87; 95 CI 2.46–13.97) of those without any of these factors. Conclusion pT4 and lymphatic, venous or perineural invasion are confirmed as significant prognostic factors in Stage II colon cancer and should be taken into account in the clinical validation process of new molecular prognostic factors.

PARP inhibitors (PARPi) for the treatment of BRCA1 or BRCA2 deficient tumours are currently the focus of seminal clinical trials exploiting the concept of synthetic lethality. Although clinical resistance to PARPi has been described, the mechanism underlying this has not been elucidated. Here, we investigate tumour material from patients who had developed resistance to the PARPi olaparib, subsequent to showing an initial clinical response. Massively parallel DNA sequencing of treatment-naive and post-olaparib treatment biopsies identified tumour-specific BRCA2 secondary mutations in olaparib-resistant metastases. These secondary mutations restored full-length BRCA2 protein, and most likely cause olaparib resistance by re-establishing BRCA2 function in the tumour cells.

Moderate intake of sherry by rats resulted in a decrease in serum total cholesterol and an increase in the proportion of high-density lipoprotein cholesterol. Oloroso, manzanilla, fino and amontillado sherries all exerted similar effects. These effects were apparently not related to the ethanol content, since an aqueous solution of ethanol did not modify cholesterol levels. Therefore other compounds must be responsible for the effects observed. This paper shows that, in addition to typical red and white wines, sherries should be included in the list of wines with beneficial physiological effects following moderate consumption. Copyright © 2004 Society of Chemical Industry