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The British Journal of Radiology Jul 2012Recent developments in imaging technology have enabled CT and MR cholangiopancreatography (MRCP) to provide minimally invasive alternatives to endoscopic retrograde... (Comparative Study)
Comparative Study Review
Recent developments in imaging technology have enabled CT and MR cholangiopancreatography (MRCP) to provide minimally invasive alternatives to endoscopic retrograde cholangiopancreatography for the pre- and post-operative assessment of biliary disease. This article describes anatomical variants of the biliary tree with surgical significance, followed by comparison of CT and MR cholangiographies. Drip infusion cholangiography with CT (DIC-CT) enables high-resolution three-dimensional anatomical representation of very small bile ducts (e.g. aberrant branches, the caudate branch and the cystic duct), which are potential causes of surgical complications. The disadvantages of DIC-CT include the possibility of adverse reactions to biliary contrast media and insufficient depiction of bile ducts caused by liver dysfunction or obstructive jaundice. Conventional MRCP is a standard, non-invasive method for evaluating the biliary tree. MRCP provides useful information, especially regarding the extrahepatic bile ducts and dilated intrahepatic bile ducts. Gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid-enhanced MRCP may facilitate the evaluation of biliary structure and excretory function. Understanding the characteristics of each type of cholangiography is important to ensure sufficient perioperative evaluation of the biliary system.
Topics: Adult; Aged; Biliary Tract; Biliary Tract Diseases; Biliary Tract Neoplasms; Cholangiography; Cholangiopancreatography, Magnetic Resonance; Contrast Media; Female; Gadolinium DTPA; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Perioperative Care; Radiographic Image Enhancement; Risk Assessment; Sensitivity and Specificity; Tomography, X-Ray Computed
PubMed: 22422383
DOI: 10.1259/bjr/21209407 -
Developmental Cell Dec 2023The extrahepatic branches of the biliary tree have glands that connect to the surface epithelium through narrow pits. The duct epithelia undergo homeostatic renewal, yet...
The extrahepatic branches of the biliary tree have glands that connect to the surface epithelium through narrow pits. The duct epithelia undergo homeostatic renewal, yet the identity and multiplicity of cells that maintain this tissue is unknown. Using marker-free and targeted clonal fate mapping in mice, we provide evidence that the extrahepatic bile duct is compartmentalized. Pit cholangiocytes of extramural glands renewed the surface epithelium, whereas basally oriented cholangiocytes maintained the gland itself. In contrast, basally positioned cholangiocytes replenished the surface epithelium in mural glands. Single-cell sequencing identified genes enriched in the base and surface epithelial populations, with trajectory analysis showing graded gene expression between these compartments. Epithelia were plastic, changing cellular identity upon fasting and refeeding. Gain of canonical Wnt signaling caused basal cell expansion, gastric chief cell marker expression, and a decrease in surface epithelial markers. Our results identify the cellular hierarchy governing extrahepatic biliary epithelial renewal.
Topics: Animals; Mice; Biliary Tract; Bile Ducts, Extrahepatic; Epithelium; Epithelial Cells; Cell Proliferation
PubMed: 37909044
DOI: 10.1016/j.devcel.2023.10.004 -
International Journal of Molecular... Sep 2018Two distinct stem/progenitor cell populations of biliary origin have been identified in the adult liver and biliary tree. Hepatic Stem/progenitor Cells (HpSCs) are... (Review)
Review
Two distinct stem/progenitor cell populations of biliary origin have been identified in the adult liver and biliary tree. Hepatic Stem/progenitor Cells (HpSCs) are bipotent progenitor cells located within the canals of Hering and can be differentiated into mature hepatocytes and cholangiocytes; Biliary Tree Stem/progenitor Cells (BTSCs) are multipotent stem cells located within the peribiliary glands of large intrahepatic and extrahepatic bile ducts and able to differentiate into hepatic and pancreatic lineages. HpSCs and BTSCs are endowed in a specialized niche constituted by supporting cells and extracellular matrix compounds. The actual contribution of these stem cell niches to liver and biliary tree homeostatic regeneration is marginal; this is due to the high replicative capabilities and plasticity of mature parenchymal cells (i.e., hepatocytes and cholangiocytes). However, the study of human liver and biliary diseases disclosed how these stem cell niches are involved in the regenerative response after extensive and/or chronic injuries, with the activation of specific signaling pathways. The present review summarizes the contribution of stem/progenitor cell niches in human liver diseases, underlining mechanisms of activation and clinical implications, including fibrogenesis and disease progression.
Topics: Animals; Biliary Tract; Biliary Tract Diseases; Disease Progression; Humans; Liver; Liver Diseases; Liver Regeneration; Regeneration; Signal Transduction; Stem Cell Niche; Stem Cells
PubMed: 30257529
DOI: 10.3390/ijms19102917 -
Current Opinion in Gastroenterology May 2011Cells lining the biliary tree are targets of injury, but also orchestrate liver repair. The latter involves autocrine/paracrine signaling that enhances the viability and... (Review)
Review
PURPOSE OF REVIEW
Cells lining the biliary tree are targets of injury, but also orchestrate liver repair. The latter involves autocrine/paracrine signaling that enhances the viability and growth of residual ductular cells and promotes accumulation of inflammatory and myofibroblastic cells. The mechanisms mediating this so-called 'ductular reaction' need to be better understood to improve injury outcomes. Studies are revealing that ductular cells produce and respond to hedgehog (Hh) ligands, developmental morphogens that control progenitor cell fate and tissue construction during embryogenesis. Because this has potential implications for liver repair, this review will summarize current knowledge about Hh signaling and cholangiocytes.
RECENT FINDINGS
Diverse types of liver injury stimulate cholangiocytes to generate Hh ligands, and cholangiocyte-derived Hh ligands interact with receptors on cholangiocytes and neighboring cells to modulate virtually every aspect of the ductular reaction to injury. Excessive Hh signaling promotes dysfunctional repair and results in chronic hepatic inflammation, fibrogenesis, and carcinogenesis.
SUMMARY
The Hh pathway is part of the complex signaling network that orchestrates liver repair. How other pathways and posttranscriptional mechanisms modulate Hh signaling in ductular cells remains unclear. Further research in this area may identify novel therapeutic targets for the treatment of cholangiopathies and cholangiocarcinoma.
Topics: Biliary Tract; Biliary Tract Diseases; Cholangiocarcinoma; Epithelium; Hedgehog Proteins; Humans; Liver; Liver Diseases; Phenotype; Signal Transduction
PubMed: 21423008
DOI: 10.1097/MOG.0b013e32834550b4 -
Canadian Medical Association Journal Jan 1955
Topics: Biliary Tract; Cholangiography; Contrast Media; Humans; Radiography, Abdominal
PubMed: 13230992
DOI: No ID Found -
AJR. American Journal of Roentgenology Apr 2012The purpose of this essay is to illustrate the imaging findings of congenital cystic lesions of the biliary tract. (Review)
Review
OBJECTIVE
The purpose of this essay is to illustrate the imaging findings of congenital cystic lesions of the biliary tract.
CONCLUSION
Congenital cystic lesions of the biliary tract include ductal plate malformations and choledochal cysts and can be recognized with characteristic imaging findings and basic knowledge of the embryologic development of the biliary tree.
Topics: Biliary Tract; Choledochal Cyst; Contrast Media; Diagnosis, Differential; Diagnostic Imaging; Humans
PubMed: 22451547
DOI: 10.2214/AJR.11.7294 -
Journal of Anatomy Sep 2021The study of the fractal architecture of various organs and structures expanded the possibilities for determining the ranges of their functioning and structural...
The study of the fractal architecture of various organs and structures expanded the possibilities for determining the ranges of their functioning and structural arrangement, which, as a result, was reflected in the development of new approaches to diagnostics and therapeutic impacts. The architecture of the excretory duct systems, similar to the hemo- and lymph- circulatory beds and the bronchial tree, is considered fractal. At the same time, information about hitherto unknown structures of the biliary tree continues to appear in the literature. We aimed to study the features of the spatial geometry of the biliary tree and assess the significance of both its fractal and Euclidean characteristics for the development of approaches that facilitate comprehensive description of intrahepatic biliary tract architecture. We investigated the architecture of the biliary trees of six men, seven male canines, and seven male Wistar rats using the corrosion casting method. Corrosion casts were prepared by injecting solidifying latexes into the bile ducts. The preparations were studied using a light stereomicroscope and a scanning electron microscope. Biliary tree branching is of various types. In addition, the correlation between variations in the caliber and length of the bile ducts and their order is not significant. Therefore, the biliary tree should not be considered as a classical fractal and it consists of the main modules, represented by the network of the bile canaliculi (first nonfractal module) and a biliary tree with a fractal branching (second module) that drains the bile canaliculi mesh and the additional modules represented by the mucosal biliary glands (in mammals with the gallbladder) or the periportal biliary plexus (in mammals without a gallbladder) and the aberrant biliary ducts. Such a configuration of the biliary bed should optimally ensure the smooth implementation of the physiological function of the liver, as well as its adaptation to different pathologies accompanied by biliary hypertension. It also might be considered in the diagnosis and assessment of ductular reaction, biliary regeneration, and/or carcinogenesis.
Topics: Animals; Biliary Tract; Corrosion Casting; Dogs; Humans; Liver; Male; Rats; Rats, Wistar
PubMed: 33817796
DOI: 10.1111/joa.13441 -
Annals of Hepatology Dec 2021The mechanism of damage of the biliary epithelium remains partially unexplored. However, recently many works have offered new evidence regarding the cholangiocytes'... (Review)
Review
The mechanism of damage of the biliary epithelium remains partially unexplored. However, recently many works have offered new evidence regarding the cholangiocytes' damage process, which is the main target in a broad spectrum of pathologies ranging from acute cholestasis, cholangiopathies to cholangiocarcinoma. This is encouraging since some works addressed this epithelium's relevance in health and disease until a few years ago. The biliary tree in the liver, comprised of cholangiocytes, is a pipeline for bile flow and regulates key hepatic processes such as proliferation, regeneration, immune response, and signaling. This review aimed to compile the most recent advances on the mechanisms of cholangiocellular damage during cholestasis, which, although it is present in many cholangiopathies, is not necessarily a common or conserved process in all of them, having a relevant role cAMP and PKA during obstructive cholestasis, as well as Ca-dependent PKC in functional cholestasis. Cholangiocellular damage could vary according to the type of cholestasis, the aggressor, or the bile ducts' location where it develops and what kind of damage can favor cholangiocellular carcinoma development.
Topics: Animals; Biliary Tract; Biliary Tract Surgical Procedures; Cell Proliferation; Cholestasis; Humans; Ligation; Oxidative Stress; Reactive Oxygen Species; Signal Transduction
PubMed: 34509686
DOI: 10.1016/j.aohep.2021.100530 -
Journal of Veterinary Internal Medicine 1992Disorders of the gallbladder and extrahepatic biliary tract in the dog and cat can easily be confused with other intra-abdominal disorders. This confusion results... (Review)
Review
Disorders of the gallbladder and extrahepatic biliary tract in the dog and cat can easily be confused with other intra-abdominal disorders. This confusion results because many times the clinical course and signs of biliary tract disease are similar to these other intra-abdominal disorders. This review discusses the normal anatomy and physiology of the gallbladder, bile duct, and bile in the dog and cat and then summarizes the historic, physical examination, clinicopathologic, diagnostic, histologic and therapeutic aspects of all the cases of extrahepatic biliary tract disease reported in the veterinary literature.
Topics: Animals; Bile; Bile Ducts; Biliary Tract Diseases; Cat Diseases; Cats; Dog Diseases; Dogs; Gallbladder; Gallbladder Diseases
PubMed: 1619596
DOI: 10.1111/j.1939-1676.1992.tb00335.x -
The Anatomical Record. Part A,... Sep 2004The extrahepatic biliary tract is innervated by dense networks of extrinsic and intrinsic nerves that regulates smooth muscle tone and epithelial cell function of... (Comparative Study)
Comparative Study Review
The extrahepatic biliary tract is innervated by dense networks of extrinsic and intrinsic nerves that regulates smooth muscle tone and epithelial cell function of extrahepatic biliary tree. Although these ganglia are derived from the same set of precursor neural crest cells that colonize the gut, they exhibit structural, neurochemical, and physiological characteristics that are distinct from the neurons of the enteric nervous system. Gallbladder neurons are relatively inexcitable, and their output is driven by vagal inputs and modulated by hormones, peptides released from sensory fibers, and inflammatory mediators. Gallbladder neurons are cholinergic and they can express a number of other neural active compounds, including substance P, galanin, nitric oxide, and vasoactive intestinal peptide. Sphincter of Oddi (SO) ganglia, which are connected to ganglia of the duodenum, appear to be comprised of distinct populations of excitatory and inhibitory neurons, based on their expression of choline acetyltransferase and substance P or nitric oxide synthase, respectively. While SO neurons likely receive vagal input and their activity is modulated by release of neuropeptides from sensory fibers, a significant source of excitatory synaptic input to these cells arise from the duodenum. This duodenum-SO circuit is likely to play an important role in the coordination of SO tone with gallbladder motility in the process of gallbladder emptying. Now that we have gained a relatively thorough understanding of the innervation of the biliary tree under healthy conditions, the way is paved for future studies of altered neural function in biliary disease.
Topics: Animals; Bile Ducts, Extrahepatic; Gallbladder; Ganglia, Autonomic; Humans; Neurons; Vertebrates
PubMed: 15382017
DOI: 10.1002/ar.a.20089