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1.
Nature ; 630(8015): 166-173, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38778114

RESUMEN

For many adult human organs, tissue regeneration during chronic disease remains a controversial subject. Regenerative processes are easily observed in animal models, and their underlying mechanisms are becoming well characterized1-4, but technical challenges and ethical aspects are limiting the validation of these results in humans. We decided to address this difficulty with respect to the liver. This organ displays the remarkable ability to regenerate after acute injury, although liver regeneration in the context of recurring injury remains to be fully demonstrated. Here we performed single-nucleus RNA sequencing (snRNA-seq) on 47 liver biopsies from patients with different stages of metabolic dysfunction-associated steatotic liver disease to establish a cellular map of the liver during disease progression. We then combined these single-cell-level data with advanced 3D imaging to reveal profound changes in the liver architecture. Hepatocytes lose their zonation and considerable reorganization of the biliary tree takes place. More importantly, our study uncovers transdifferentiation events that occur between hepatocytes and cholangiocytes without the presence of adult stem cells or developmental progenitor activation. Detailed analyses and functional validations using cholangiocyte organoids confirm the importance of the PI3K-AKT-mTOR pathway in this process, thereby connecting this acquisition of plasticity to insulin signalling. Together, our data indicate that chronic injury creates an environment that induces cellular plasticity in human organs, and understanding the underlying mechanisms of this process could open new therapeutic avenues in the management of chronic diseases.


Asunto(s)
Transdiferenciación Celular , Hepatocitos , Hepatopatías , Hígado , Humanos , Sistema Biliar/citología , Sistema Biliar/metabolismo , Sistema Biliar/patología , Biopsia , Plasticidad de la Célula , Enfermedad Crónica , Progresión de la Enfermedad , Células Epiteliales/metabolismo , Células Epiteliales/citología , Células Epiteliales/patología , Hepatocitos/metabolismo , Hepatocitos/citología , Hepatocitos/patología , Insulina/metabolismo , Hígado/patología , Hígado/metabolismo , Hígado/citología , Hepatopatías/patología , Hepatopatías/metabolismo , Regeneración Hepática , Organoides/metabolismo , Organoides/patología , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , RNA-Seq , Transducción de Señal , Análisis de la Célula Individual , Serina-Treonina Quinasas TOR/metabolismo
2.
Eur Radiol ; 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38526750

RESUMEN

BACKGROUND: Personalising management of primary oesophageal adenocarcinoma requires better risk stratification. Lack of independent validation of proposed imaging biomarkers has hampered clinical translation. We aimed to prospectively validate previously identified prognostic grey-level co-occurrence matrix (GLCM) CT features for 3-year overall survival. METHODS: Following ethical approval, clinical and contrast-enhanced CT data were acquired from participants from five institutions. Data from three institutions were used for training and two for testing. Survival classifiers were modelled on prespecified variables ('Clinical' model: age, clinical T-stage, clinical N-stage; 'ClinVol' model: clinical features + CT tumour volume; 'ClinRad' model: ClinVol features + GLCM_Correlation and GLCM_Contrast). To reflect current clinical practice, baseline stage was also modelled as a univariate predictor ('Stage'). Discrimination was assessed by area under the receiver operating curve (AUC) analysis; calibration by Brier scores; and clinical relevance by thresholding risk scores to achieve 90% sensitivity for 3-year mortality. RESULTS: A total of 162 participants were included (144 male; median 67 years [IQR 59, 72]; training, 95 participants; testing, 67 participants). Median survival was 998 days [IQR 486, 1594]. The ClinRad model yielded the greatest test discrimination (AUC, 0.68 [95% CI 0.54, 0.81]) that outperformed Stage (ΔAUC, 0.12 [95% CI 0.01, 0.23]; p = .04). The Clinical and ClinVol models yielded comparable test discrimination (AUC, 0.66 [95% CI 0.51, 0.80] vs. 0.65 [95% CI 0.50, 0.79]; p > .05). Test sensitivity of 90% was achieved by ClinRad and Stage models only. CONCLUSIONS: Compared to Stage, multivariable models of prespecified clinical and radiomic variables yielded improved prediction of 3-year overall survival. CLINICAL RELEVANCE STATEMENT: Previously identified radiomic features are prognostic but may not substantially improve risk stratification on their own. KEY POINTS: • Better risk stratification is needed in primary oesophageal cancer to personalise management. • Previously identified CT features-GLCM_Correlation and GLCM_Contrast-contain incremental prognostic information to age and clinical stage. • Compared to staging, multivariable clinicoradiomic models improve discrimination of 3-year overall survival.

3.
Eur Radiol ; 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38488970

RESUMEN

BACKGROUND: The Paris classification categorises colorectal polyp morphology. Interobserver agreement for Paris classification has been assessed at optical colonoscopy (OC) but not CT colonography (CTC). We aimed to determine the following: (1) interobserver agreement for the Paris classification using CTC between radiologists; (2) if radiologist experience influenced classification, gross polyp morphology, or polyp size; and (3) the extent to which radiologist classifications agreed with (a) colonoscopy and (b) a combined reference standard. METHODS: Following ethical approval for this non-randomised prospective cohort study, seven radiologists from three hospitals classified 52 colonic polyps using the Paris system. We calculated interobserver agreement using Fleiss kappa and mean pairwise agreement (MPA). Absolute agreement was calculated between radiologists; between CTC and OC; and between CTC and a combined reference standard using all available imaging, colonoscopic, and histopathological data. RESULTS: Overall interobserver agreement between the seven readers was fair (Fleiss kappa 0.33; 95% CI 0.30-0.37; MPA 49.7%). Readers with < 1500 CTC experience had higher interobserver agreement (0.42 (95% CI 0.35-0.48) vs. 0.33 (95% CI 0.25-0.42)) and MPA (69.2% vs 50.6%) than readers with ≥ 1500 experience. There was substantial overall agreement for flat vs protuberant polyps (0.62 (95% CI 0.56-0.68)) with a MPA of 87.9%. Agreement between CTC and OC classifications was only 44%, and CTC agreement with the combined reference standard was 56%. CONCLUSION: Radiologist agreement when using the Paris classification at CT colonography is low, and radiologist classification agrees poorly with colonoscopy. Using the full Paris classification in routine CTC reporting is of questionable value. CLINICAL RELEVANCE STATEMENT: Interobserver agreement for radiologists using the Paris classification to categorise colorectal polyp morphology is only fair; routine use of the full Paris classification at CT colonography is questionable. KEY POINTS: • Overall interobserver agreement for the Paris classification at CT colonography (CTC) was only fair, and lower than for colonoscopy. • Agreement was higher for radiologists with < 1500 CTC experience and for larger polyps. There was substantial agreement when classifying polyps as protuberant vs flat. • Agreement between CTC and colonoscopic polyp classification was low (44%).

4.
Contemp Clin Trials ; 134: 107352, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37802221

RESUMEN

Non-alcoholic fatty liver disease (NAFLD) is the liver manifestation of the metabolic syndrome with global prevalence reaching epidemic levels. Despite the high disease burden in the population only a small proportion of those with NAFLD will develop progressive liver disease, for which there is currently no approved pharmacotherapy. Identifying those who are at risk of progressive NAFLD currently requires a liver biopsy which is problematic. Firstly, liver biopsy is invasive and therefore not appropriate for use in a condition like NAFLD that affects a large proportion of the population. Secondly, biopsy is limited by sampling and observer dependent variability which can lead to misclassification of disease severity. Non-invasive biomarkers are therefore needed to replace liver biopsy in the assessment of NAFLD. Our study addresses this unmet need. The LITMUS Imaging Study is a prospectively recruited multi-centre cohort study evaluating magnetic resonance imaging and elastography, and ultrasound elastography against liver histology as the reference standard. Imaging biomarkers and biopsy are acquired within a 100-day window. The study employs standardised processes for imaging data collection and analysis as well as a real time central monitoring and quality control process for all the data submitted for analysis. It is anticipated that the high-quality data generated from this study will underpin changes in clinical practice for the benefit of people with NAFLD. Study Registration: clinicaltrials.gov: NCT05479721.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Humanos , Enfermedad del Hígado Graso no Alcohólico/diagnóstico por imagen , Enfermedad del Hígado Graso no Alcohólico/patología , Estudios de Cohortes , Hígado/diagnóstico por imagen , Hígado/patología , Cirrosis Hepática/diagnóstico por imagen , Cirrosis Hepática/patología , Imagen por Resonancia Magnética/métodos , Biomarcadores
5.
Colorectal Dis ; 25(8): 1708-1712, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37432059

RESUMEN

AIM: The incidence of benign colonic anastomotic stricture is approximately 2% in patients undergoing left hemicolectomy or anterior resection and as high as 16% in patients undergoing low anterior or intersphincteric resection. In the majority, rather than complete occlusion, a stenosis forms, which can be managed with endoscopic balloon dilatation, a self-expanding metallic stent or endoscopic electroincision. In the less common scenario of a completely occluded colonic anastomosis, surgery is often required. In this study, we aim to describe the technique we used to treat this condition non-operatively METHOD: We describe a case series of three patients with benign complete occlusion of their colorectal anastomosis and how we managed them nonoperatively with a colonic/rectal endoscopic ultrasound (EUS) anastomosis technique and a Hot lumen-apposing metallic stent. RESULTS: We demonstrate that the technical and clinical success for this technique is 100%. CONCLUSIONS: We believe that the technique we describe is effective and safe. It should be widely reproducible in centres with expertise in interventional EUS, given the similarity to well-established procedures such as EUS-guided gastroenterostomy. Patient selection and timing of reversal of ileostomy need careful consideration, especially in patients with a history of keloid formation. Given the shorter hospital stay and reduced invasiveness of this technique, we believe it should be considered for all patients who have complete benign occlusion of a colonic anastomosis. However, given the small number of cases and short period of follow-up, the long-term outcome of this technique is not known. More studies with higher power and a longer period of follow-up should be conducted to further ascertain the effectiveness of this technique.


Asunto(s)
Colostomía , Obstrucción Intestinal , Humanos , Colostomía/métodos , Colon/diagnóstico por imagen , Colon/cirugía , Endosonografía/métodos , Anastomosis Quirúrgica/métodos , Obstrucción Intestinal/etiología , Stents/efectos adversos , Ultrasonografía Intervencional , Estudios Retrospectivos
6.
Dig Dis Sci ; 68(6): 2704-2709, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36929239

RESUMEN

BACKGROUND: The clinical benefit of venesection in suspected iron overload can be unclear and serum ferritin may overestimate the degree of iron overload. AIMS: To help inform practice, we examined magnetic resonance liver iron concentration (MRLIC) in a cohort investigated for haemochromatosis. METHODS: One hundred and six subjects with suspected haemochromatosis underwent HFE genotyping and MRLIC with time-matched serum ferritin and transferrin saturation values. For those treated with venesection, volume of blood removed was calculated as a measure of iron overload. RESULTS: Forty-seven C282Y homozygotes had median ferritin 937 µg/l and MRLIC 4.83 mg/g; MRLIC was significantly higher vs non-homozygotes for any given ferritin concentration. No significant difference in MRLIC was observed between homozygotes with and without additional risk factors for hyperferritinemia. Thirty-three compound heterozygotes (C282Y/H63D) had median ferritin 767 µg/l and MRLIC 2.58 mg/g; ferritin < 750 µg/l showed 100% specificity for lack of significant iron overload (< 3.2 mg/g). 79% of C282Y/H63D had additional risk factors-mean MRLIC was significantly lower in this sub-group (2.4 mg/g vs 3.23 mg/g). 26 C282Y heterozygous or wild-type had median ferritin 1226 µg/l and MRLIC 2.13 mg/g; 69% with additional risk factors had significantly higher ferritin concentrations (with comparable MRLIC) and ferritin < 1000 µg/l showed 100% specificity for lack of significant iron overload. In 31 patients (26 homozygotes, 5 C282Y/H63D) venesected to ferritin < 100 µg/l, MRLIC and total venesection volume correlated strongly (r = 0.749), unlike MRLIC and serum ferritin. CONCLUSION: MRLIC is an accurate marker of iron overload in haemochromatosis. We propose serum ferritin thresholds in non-homozygotes which, if validated, could tailor cost-effective use of MRLIC in venesection decision-making.


Asunto(s)
Hemocromatosis , Hiperferritinemia , Sobrecarga de Hierro , Humanos , Hemocromatosis/diagnóstico , Hemocromatosis/genética , Genotipo , Flebotomía , Antígenos de Histocompatibilidad Clase I/genética , Proteína de la Hemocromatosis/genética , Sobrecarga de Hierro/genética , Ferritinas , Hierro , Hígado/diagnóstico por imagen , Hígado/metabolismo , Espectroscopía de Resonancia Magnética
7.
Clin Gastroenterol Hepatol ; 21(2): 535-537.e1, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-35032633

RESUMEN

Splenomegaly in the context of liver disease is classically associated with advanced cirrhosis and portal hypertension.1 More recently, we observed an increasing number of patients with splenomegaly and nonalcoholic fatty liver disease (NAFLD), but in whom intensive work-up revealed no evidence of advanced liver disease or portal hypertension. In this study, we found no correlation between spleen size and histological stage of NAFLD, and a strong correlation between body weight, height and serum high density lipoprotein (HDL) levels.


Asunto(s)
Hipertensión Portal , Enfermedad del Hígado Graso no Alcohólico , Humanos , Enfermedad del Hígado Graso no Alcohólico/patología , Bazo/patología , Esplenomegalia/etiología , Hígado/patología , Cirrosis Hepática/patología , Hipertensión Portal/complicaciones
8.
Eur Radiol ; 32(12): 8306-8316, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35732929

RESUMEN

There are a range of sphincter-preserving procedures available to treat anorectal fistula, some of which can be precluded, or rendered more optimal by specific features of fistula anatomy. Magnetic resonance imaging (MRI) is the gold standard modality for assessing anorectal fistula. To maximise clinical utility, the MRI report should accurately describe these clinically relevant features. We aimed to develop a minimum dataset for reporting MRI of anorectal fistula, in order to improve the assessment and management of these patients. A longlist of 70 potential items for the minimum dataset was generated through systematic review of the literature. This longlist was presented to radiologists, surgeons and gastroenterologists in an online survey to understand the features that shape current clinical practice. The longlist and survey results were then presented to an expert consensus panel to generate the final minimum dataset through discussion and anonymous voting. The final minimum dataset details the general characteristics, features of the internal and external openings, path of the fistula through the sphincters and any associated extensions and collections that should be described in all MRI reports for anal fistula. Additional surgical and perianal Crohn's disease subsets were developed to indicate the features that aid decision-making for these patients, in addition to a minimum dataset for the clinical request. This study represents a multi-disciplinary approach to developing a minimum dataset for MRI reporting of anal fistula, highlighting the most important features to report that can assist in clinical decision-making. KEY POINTS: • This paper recommends the minimum features that should be included in all MRI reports for the assessment of anal fistula, including Parks classification, number of tracts, features of the internal and external opening, path of the tract through the sphincters, the presence and features of extensions and collections. • Additional features that aid decision-making for surgery or in the presence of Crohn's disease have been identified. • The items that should be included when requesting an MRI are specified.


Asunto(s)
Enfermedad de Crohn , Fístula Rectal , Humanos , Consenso , Fístula Rectal/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Toma de Decisiones Clínicas
9.
J Clin Endocrinol Metab ; 107(6): e2532-e2544, 2022 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-35137184

RESUMEN

CONTEXT: Genetic variants affecting the nuclear hormone receptor coactivator steroid receptor coactivator, SRC-1, have been identified in people with severe obesity and impair melanocortin signaling in cells and mice. As a result, obese patients with SRC-1 deficiency are being treated with a melanocortin 4 receptor agonist in clinical trials. OBJECTIVE: Here, our aim was to comprehensively describe and characterize the clinical phenotype of SRC-1 variant carriers to facilitate diagnosis and clinical management. METHODS: In genetic studies of 2462 people with severe obesity, we identified 23 rare heterozygous variants in SRC-1. We studied 29 adults and 18 children who were SRC-1 variant carriers and performed measurements of metabolic and endocrine function, liver imaging, and adipose tissue biopsies. Findings in adult SRC-1 variant carriers were compared to 30 age- and body mass index (BMI)-matched controls. RESULTS: The clinical spectrum of SRC-1 variant carriers included increased food intake in children, normal basal metabolic rate, multiple fractures with minimal trauma (40%), persistent diarrhea, partial thyroid hormone resistance, and menorrhagia. Compared to age-, sex-, and BMI-matched controls, adult SRC-1 variant carriers had more severe adipose tissue fibrosis (46.2% vs 7.1% respectively, P = .03) and a suggestion of increased liver fibrosis (5/13 cases vs 2/13 in controls, odds ratio = 3.4), although this was not statistically significant. CONCLUSION: SRC-1 variant carriers exhibit hyperphagia in childhood, severe obesity, and clinical features of partial hormone resistance. The presence of adipose tissue fibrosis and hepatic fibrosis in young patients suggests that close monitoring for the early development of obesity-associated metabolic complications is warranted.


Asunto(s)
Coactivador 1 de Receptor Nuclear , Obesidad Mórbida , Femenino , Fibrosis , Humanos , Masculino , Coactivador 1 de Receptor Nuclear/genética , Obesidad Mórbida/complicaciones , Obesidad Mórbida/genética
10.
BMJ Support Palliat Care ; 12(1): 22-28, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34635545

RESUMEN

Pancreatic cancer has a very poor prognosis with patients often presenting with locally advanced, inoperable or metastatic disease. A significant proportion of patients have visceral pain due to perineural infiltration or coeliac plexus involvement by the tumour. This pain is difficult to control and may become refractory to conventional pain management. Therefore, coeliac plexus neurolysis (CPN) has been proposed to ablate the neuronal transmission pathway of pain permanently. CPN is recommended for those who have uncontrolled pain, are experiencing unacceptable opioid adverse effects or are receiving escalating doses of analgesics. It is not known whether CPN performed at diagnosis as the first-line treatment ('early') would impact short-term and long-term pain control and quality of life. NICE has recommended (2018) a randomised trial comparing early endoscopic ultrasound-guided coeliac plexus neurolysis (EUS-CPN) with on-demand EUS-CPN in pancreatic cancer. In this context, we will review the current evidence on its clinical benefits.


Asunto(s)
Plexo Celíaco , Neoplasias Pancreáticas , Plexo Celíaco/diagnóstico por imagen , Plexo Celíaco/patología , Endosonografía , Humanos , Neoplasias Pancreáticas/complicaciones , Neoplasias Pancreáticas/patología , Calidad de Vida , Ultrasonografía Intervencional
11.
J Surg Case Rep ; 2021(9): rjab410, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34531975

RESUMEN

Percutaneous cholecystostomy is a treatment for acute calculous cholecystitis used in patients where surgery is high risk or challenging either to allow for surgical optimisation or as definitive treatment. In this case series we compare the outcomes of a transhepatic versus transperitoneal approach in patients undergoing percutaneous cholecystostomy for acute calculous cholecystitis. A retrospective review of patients from 2014 to 2019 was conducted and included demographics, percutaneous cholecystostomy route, complications and outcome. Fifty-one patients were included. Percutaneous cholecystostomy was placed transhepatically in 15 cases; transperitoneal in 30 cases; 6 cases had undetermined route. The transhepatic cohort had 43.5% fewer readmissions due to biliary sepsis, 32.5% fewer drain-related complications, and were less likely to require further treatment (32.5% reduction) compared to the transperitoneal cohort. In our experience, the transhepatic route is preferred due to fewer complications, fewer readmissions and a reduction in the need for further treatment.

12.
Science ; 371(6531): 839-846, 2021 02 19.
Artículo en Inglés | MEDLINE | ID: mdl-33602855

RESUMEN

Organoid technology holds great promise for regenerative medicine but has not yet been applied to humans. We address this challenge using cholangiocyte organoids in the context of cholangiopathies, which represent a key reason for liver transplantation. Using single-cell RNA sequencing, we show that primary human cholangiocytes display transcriptional diversity that is lost in organoid culture. However, cholangiocyte organoids remain plastic and resume their in vivo signatures when transplanted back in the biliary tree. We then utilize a model of cell engraftment in human livers undergoing ex vivo normothermic perfusion to demonstrate that this property allows extrahepatic organoids to repair human intrahepatic ducts after transplantation. Our results provide proof of principle that cholangiocyte organoids can be used to repair human biliary epithelium.


Asunto(s)
Enfermedades de los Conductos Biliares/terapia , Conductos Biliares Intrahepáticos/fisiología , Conductos Biliares/citología , Tratamiento Basado en Trasplante de Células y Tejidos , Células Epiteliales/citología , Organoides/trasplante , Animales , Bilis , Conductos Biliares/fisiología , Conductos Biliares Intrahepáticos/citología , Conducto Colédoco/citología , Células Epiteliales/fisiología , Vesícula Biliar/citología , Regulación de la Expresión Génica , Humanos , Hígado/fisiología , Trasplante de Hígado , Trasplante de Células Madre Mesenquimatosas , Ratones , Organoides/fisiología , RNA-Seq , Obtención de Tejidos y Órganos , Transcriptoma
13.
Endosc Int Open ; 8(11): E1537-E1544, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33140008

RESUMEN

Background and study aims Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) has emerged as an important method for obtaining a preoperative tissue diagnosis for suspected cholangiocarcinoma. However, doubts remain about test sensitivity. This study assessed the value and limitations of EUS-FNA in clinical practice. Patients and methods Patients undergoing EUS-FNA for biliary strictures/masses at a UK tertiary referral center from 2005 to 2014 were prospectively enrolled. Data on EUS-FNA findings, histology, and endoscopy and patient outcomes were collected to evaluate test performance and identify factors predictive of an inaccurate diagnostic result. Results Ninety-seven patients underwent a total of 112 EUS-FNA procedures. Overall test sensitivity for an initial EUS-FNA for suspected cholangiocarcinoma was 75 % (95 % CI 64 %-84 %), with specificity 100 % (95 % CI 85 %-100 %) and negative predictive value 0.62 (95 % CI 0.47-0.75). Hilar lesions, the presence of a biliary stent, and a diagnosis of PSC were significantly independently associated with an inaccurate result. For the most difficult cases, repeat sampling and use of the Papanicolaou cytopathology grading scale led to an increase in test sensitivity from 17 % to 100 % ( P  = 0.015) with no loss of specificity. Conclusions EUS-FNA was found to be a useful method for obtaining a preoperative tissue diagnosis for patients with suspected cholangiocarcinoma. This study identified markers that can reduce test accuracy and measures that can improve test performance of EUS-FNA.

14.
J Surg Case Rep ; 2020(9): rjaa369, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33005325

RESUMEN

Intestinal perforation following the ingestion of fishbone is unusual and rarely diagnosed preoperatively, as clinical and radiological findings are non-specific. We report a case of a female patient post Roux-en-Y gastric bypass (RYGBP) for obesity, who presented with severe abdominal pain and guarding in left iliac fossa. Computed tomography (CT) suggested internal herniation with compromised vascular supply to the bowel. Exploratory laparotomy identified a perforation site in the blind loop of the RYGBP due to a protruding fishbone. After extraction, primary suture repair was performed. In retrospect, the fishbone was identified on CT but misinterpreted as suture line at the enteroenterostomy site. This case emphasizes that although rare, the ingestion of fishbone can lead to severe complications and should therefore be included in the differential for an acute abdomen. On CT, it should be noted that fishbone may simulate suture line within the bowel if the patient has history of previous surgery.

15.
Sci Rep ; 10(1): 17563, 2020 10 16.
Artículo en Inglés | MEDLINE | ID: mdl-33067515

RESUMEN

Magnetic resonance imaging of the pancreas is increasingly used as an important diagnostic modality for characterisation of pancreatic lesions. Pancreatic MRI protocols are mostly qualitative due to time constraints and motion sensitivity. MR Fingerprinting is an innovative acquisition technique that provides qualitative data and quantitative parameter maps from a single free-breathing acquisition with the potential to reduce exam times. This work investigates the feasibility of MRF parameter mapping for pancreatic imaging in the presence of free-breathing exam. Sixteen healthy participants were prospectively imaged using MRF framework. Regions-of-interest were drawn in multiple solid organs including the pancreas and T1 and T2 values determined. MRF T1 and T2 mapping was performed successfully in all participants (acquisition time:2.4-3.6 min). Mean pancreatic T1 values were 37-43% lower than those of the muscle, spleen, and kidney at both 1.5 and 3.0 T. For these organs, the mean pancreatic T2 values were nearly 40% at 1.5 T and < 12% at 3.0 T. The feasibility of MRF at 1.5 T and 3 T was demonstrated in the pancreas. By enabling fast and free-breathing quantitation, MRF has the potential to add value during the clinical characterisation and grading of pathological conditions, such as pancreatitis or cancer.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética , Páncreas/diagnóstico por imagen , Respiración , Adulto , Algoritmos , Femenino , Humanos , Masculino , Movimiento (Física) , Reconocimiento de Normas Patrones Automatizadas , Fantasmas de Imagen , Estudios Prospectivos
16.
Proc Natl Acad Sci U S A ; 117(46): 28960-28970, 2020 11 17.
Artículo en Inglés | MEDLINE | ID: mdl-33127761

RESUMEN

Inhibition of the chemokine receptor CXCR4 in combination with blockade of the PD-1/PD-L1 T cell checkpoint induces T cell infiltration and anticancer responses in murine and human pancreatic cancer. Here we elucidate the mechanism by which CXCR4 inhibition affects the tumor immune microenvironment. In human immune cell-based chemotaxis assays, we find that CXCL12-stimulated CXCR4 inhibits the directed migration mediated by CXCR1, CXCR3, CXCR5, CXCR6, and CCR2, respectively, chemokine receptors expressed by all of the immune cell types that participate in an integrated immune response. Inhibiting CXCR4 in an experimental cancer medicine study by 1-wk continuous infusion of the small-molecule inhibitor AMD3100 (plerixafor) induces an integrated immune response that is detected by transcriptional analysis of paired biopsies of metastases from patients with microsatellite stable colorectal and pancreatic cancer. This integrated immune response occurs in three other examples of immune-mediated damage to noninfected tissues: Rejecting renal allografts, melanomas clinically responding to anti-PD1 antibody therapy, and microsatellite instable colorectal cancers. Thus, signaling by CXCR4 causes immune suppression in human pancreatic ductal adenocarcinoma and colorectal cancer by impairing the function of the chemokine receptors that mediate the intratumoral accumulation of immune cells.


Asunto(s)
Neoplasias Colorrectales/metabolismo , Inmunidad/inmunología , Páncreas/metabolismo , Neoplasias Pancreáticas/metabolismo , Receptores CXCR4/efectos de los fármacos , Receptores CXCR4/metabolismo , Anciano , Bencilaminas , Carcinoma Ductal Pancreático , Quimiocina CXCL12 , Neoplasias Colorrectales/patología , Ciclamas , Femenino , Compuestos Heterocíclicos/antagonistas & inhibidores , Humanos , Inmunoterapia , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/patología , Receptores CCR2/metabolismo , Receptores CXCR3/metabolismo , Receptores CXCR5/metabolismo , Receptores CXCR6/metabolismo , Receptores de Interleucina-8A/metabolismo , Transducción de Señal/efectos de los fármacos , Microambiente Tumoral/inmunología , Neoplasias Pancreáticas
18.
Br J Radiol ; 92(1103): 20190461, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31430199

RESUMEN

OBJECTIVE: Main duct and mixed intraductal papillary mucinous neoplasms (IPMN) are pre-malignant cystic pancreatic neoplasms associated with pancreatic duct dilatation. Distinguishing these from benign causes of pancreatic duct dilatation is important in order to allow appropriate surveillance or surgery. A patulous duodenal papilla with extrusion of mucus at endoscopic evaluation, the endoscopic fish mouth ampulla (E-FMA) sign, is reported in main duct and mixed IPMN. We aimed to establish whether a CT correlate (CT-FMA) of this sign exists and whether this was associated with the presence of invasion or high-grade dysplasia. We defined the CT-FMA sign as an uninterrupted column of water attenuation material running from the pancreatic duct to the duodenal lumen. METHODS: A retrospective, blinded review of 44 patients with histologically confirmed IPMN and 87 age-matched controls with pancreatic duct dilatation on CT was undertaken. A case-control series matched for the degree of pancreatic duct dilatation was used to compare the rates of invasion or high-grade dysplasia between main duct and mixed IPMN patients, with and without a CT-FMA sign. RESULTS: The CT-FMA sign could be identified in 18.5% patients with main duct/mixed IPMN with specificity 100%, positive predictive value 100% and negative predictive value 79.8%. A significant association was found between CT-FMA in main duct/mixed IPMN compared to controls, but not with the presence of high-grade dysplasia or invasion. CONCLUSIONS: The CT-FMA sign is a newly reported, highly specific sign of MD and mixed IPMN. ADVANCES IN KNOWLEDGE: If a fish mouth ampulla is identified at CT, a diagnosis of main duct or mixed IPMN is highly likely.


Asunto(s)
Adenocarcinoma Mucinoso/diagnóstico por imagen , Carcinoma Ductal Pancreático/diagnóstico por imagen , Neoplasias Pancreáticas/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Ampolla Hepatopancreática/diagnóstico por imagen , Estudios de Casos y Controles , Humanos , Persona de Mediana Edad , Lesiones Precancerosas/diagnóstico por imagen , Estudios Retrospectivos , Tomografía Computarizada por Rayos X
20.
BMJ Case Rep ; 12(4)2019 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-30992283

RESUMEN

Portal pyaemia or pylephlebitis is a form of septic (often suppurative) thrombophlebitis of the portal venous system. It may develop as a complication of intra-abdominal sepsis, such as diverticulitis or appendicitis. Patients typically present with a high fever that is sometimes accompanied by jaundice. We report a case of portal pyaemia associated with multiple liver abscesses and discuss the medical and surgical management of this condition.


Asunto(s)
Enfermedades del Colon/complicaciones , Perforación Intestinal/complicaciones , Absceso Hepático/etiología , Flebitis/etiología , Sepsis/etiología , Antibacterianos/uso terapéutico , Anticoagulantes/uso terapéutico , Enfermedades del Colon/diagnóstico por imagen , Enfermedades del Colon/cirugía , Humanos , Perforación Intestinal/diagnóstico por imagen , Perforación Intestinal/cirugía , Masculino , Venas Mesentéricas/diagnóstico por imagen , Persona de Mediana Edad , Flebitis/tratamiento farmacológico , Sepsis/tratamiento farmacológico , Tomografía Computarizada por Rayos X
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