scholarly journals Recent advances in understanding biliary atresia

F1000Research ◽  
2019 ◽  
Vol 8 ◽  
pp. 218 ◽  
Author(s):  
Andrew Wehrman ◽  
Orith Waisbourd-Zinman ◽  
Rebecca G Wells
Keyword(s):  
Biliary Atresia ◽  
Extrahepatic Bile Duct ◽  
Biliary Tree ◽  
Liver Parenchyma ◽  
Early Diagnostics ◽  
The Past ◽  
Recent Advances ◽  
Neonatal Liver ◽  
Extrahepatic Biliary Tree ◽  
Extrahepatic Bile Duct Obstruction

Biliary atresia (BA) is a neonatal liver disease characterized by progressive obstruction and fibrosis of the extrahepatic biliary tree as well as fibrosis and inflammation of the liver parenchyma. Recent studies found that infants who will go on to develop BA have elevated direct bilirubin levels in the first few days of life, suggesting that the disease starts in utero. The etiology and pathogenesis of BA, however, remain unknown. Here, we discuss recent studies examining potential pathogenetic mechanisms of BA, including genetic susceptibility, involvement of the immune system, and environmental insults such as viruses and toxins, although it is possible that there is not a single etiological agent but rather a large group of injurious insults that result in a final common pathway of extrahepatic bile duct obstruction and liver fibrosis. The management and diagnosis of BA have not advanced significantly in the past decade, but given recent advances in understanding the timing and potential pathogenesis of BA, we are hopeful that the next decade will bring early diagnostics and novel therapeutics.

Biliary Atresia Revisited

2004 ◽  
Vol 7 (2) ◽  
pp. 109-124 ◽  
Author(s):  
Ellen Kahn
Keyword(s):  
Biliary Atresia ◽  
Congenital Anomalies ◽  
Cell Transformation ◽  
Biliary Tree ◽  
Bile Acid Metabolism ◽  
Biliary Cirrhosis ◽  
Intrahepatic Bile Ducts ◽  
Alpha 1 Antitrypsin Deficiency ◽  
Alpha 1 Antitrypsin ◽  
Extrahepatic Biliary Tree

Extrahepatic biliary atresia (EHBA) is an inflammatory fibrosing process affecting the extrahepatic and intrahepatic biliary tree resulting in fibrous obliteration of the extrahepatic biliary tract, ductopenia of intrahepatic bile ducts, and biliary cirrhosis. EHBA is divided into a correctable and a noncorrectable type with focal patency of the otherwise atretic biliary tree in the former and no patency of the biliary tree in the noncorrectable type. EHBA is divided in a fetal, prenatal or embryonic, and a more common, perinatal, acquired form. The symptoms of the former start shortly after birth and there is frequently an association with a variety of congenital anomalies. Children with the perinatal form become jaundiced several weeks after birth; no associated congenital anomalies are present. Morphologically, an inflammatory and fibrosing process of the extrahepatic biliary tree leads to complete lumenal obliteration. The liver is characterized by a nonspecific giant cell transformation, and portal expansion by fibrous connective tissue with marked ductular proliferation. With time, ductopenia and biliary cirrhosis develop. The diffential diagnosis with other conditions with similar microscopic patterns such as alpha-1 antitrypsin deficiency, total parental nutrition, obstruction by a choledochal cyst, arteriohepatic dysplasia, familial progressive intra-hepatic cholestasis, and alteration of the bile acid metabolism is discussed. In the fetal group, abnormalities in different genes seem to play a role; ductal plate malformation is another possibility. Different etiologies have been postulated in the perinatal form of EHBA: genetic susceptilibility, vascular factors, toxins, and infections mainly by rotavirus and reovirus. The pathogenesis is complex. EHBA is a heterogenous disease, resulting from a combination of genetic factors, insults, and activation of different genetic and immunologic pathways. The treatment of EHBA is surgical, with anastomosis between the biliary tree and the intestine in the correctable type and a hepatic portoenterostomy (HPE) for the noncorrectable group. HPE is a temporizing treatment allowing the infant to develop and grow, followed in the majority of the patients by liver transplantation.

scholarly journals BILIARY ATRESIA: evaluation on two distinct periods at a reference pediatric service

2014 ◽  
Vol 51 (1) ◽  
pp. 53-58 ◽  
Author(s):  
Thais Costa Nascentes QUEIROZ ◽  
Alexandre Rodrigues FERREIRA ◽  
Eleonora Druve Tavares FAGUNDES ◽  
Mariza Leitão Valadares ROQUETE ◽  
Francisco José PENNA
Keyword(s):  
Biliary Atresia ◽  
Waiting Time ◽  
Neonatal Period ◽  
Biliary Tree ◽  
Probability Of Survival ◽  
Age At Surgery ◽  
Pediatric Service ◽  
Extrahepatic Biliary Tree ◽  
Observation Period

Context Biliary atresia is a progressive, idiopathic, fibro-obliterative disease of the extrahepatic biliary tree that presents with biliary obstruction exclusively in the neonatal period. Objectives To assess the differences regarding age at referral, age at surgery, duration of propaedeutics and waiting time for surgery between two groups of infants in different periods. Methods Retrospective study of infants diagnosed with biliary atresia on two periods: 1983-1993 and 1998-2011. Results Biliary atresia was diagnosed in 129 infants, being 48 in casuistic I and 81 in casuistic II. The median age at admission was 94 and 60 days, respectively (P = 0.0001). On evaluating patients who had undergone portoenterostomy before 120 days of age, no difference was observed regarding the duration of propaedeutics or waiting time for surgery (P = 0.15), but difference was found when comparing the age at surgery (P = 0.002). Among those infants with no biliary flow and without liver transplantation or death after 18 post-operative months, the estimated probability of survival was 44.6% and 38.7% in casuistics I and II, respectively. In casuistic I, all infants who showed biliary flow were alive during the observation period and, in casuistic II, 80.3% were alive after 7 years of follow-up. Conclusions Even though patients were admitted and treated earlier, it is clear that surgery could be done sooner. Delay in referral and timely propaedeutics were the main contributors.

scholarly journals Exome Sequencing in Individuals with Isolated Biliary Atresia

2019 ◽  
Author(s):  
Ramakrishnan Rajagopalan ◽  
Ellen A. Tsai ◽  
Christopher M. Grochowski ◽  
Susan M. Kelly ◽  
Kathleen M. Loomes ◽  
...  
Keyword(s):  
Biliary Atresia ◽  
Exome Sequencing ◽  
Stress Responses ◽  
Rare Variants ◽  
De Novo ◽  
Genetic Model ◽  
Single Gene ◽  
Biliary Tree ◽  
Causal Genes ◽  
Extrahepatic Biliary Tree

AbstractBiliary atresia (BA) is a severe pediatric liver disease resulting in necroinflammatory obliteration of the extrahepatic biliary tree. BA presents within the first few months of life as either an isolated finding or with additional syndromic features. The etiology of isolated BA is unknown, with evidence for infectious, environmental, and genetic risk factors described. However, to date, there are no definitive causal genes identified for isolated BA in humans, and the question of whether single gene defects play a major role remains open. We performed exome-sequencing in 100 North American patients of European descent with isolated BA (including 30 parent-child trios) and considered several experimental designs to identify potentially deleterious protein-altering variants that may be involved in the disease. In a case-only analysis, we did not identify genes with variants shared among more than two probands, and burden tests of rare variants using a case-case control design did not yield significant results. In the trio analysis of 30 simplex families (patient and parent trios), we identified 66 de novo variants in 66 genes including a nonsense variant, p.(Cys30Ter), in the gene STIP1. STIP1 is a co-chaperone for the heat-shock protein, HSP90AA1, and has been shown to have diverse functions in yeast, flies and mammals, including stress-response.ConclusionOur results do not support the hypothesis that a simple genetic model is responsible for the majority of cases of isolated BA. Our finding of a de novo mutation in a candidate gene for BA (STIP1) linked to evolutionarily conserved stress responses suggests further exploration of how genetic susceptibility and environmental exposure interact to cause BA is warranted.

Recent Advances in Therapeutic Applications of Bisbenzimidazoles

2020 ◽  
Vol 16 (4) ◽  
pp. 454-486 ◽  
Author(s):  
Smita Verma ◽  
Vishnuvardh Ravichandiran ◽  
Nihar Ranjan ◽  
Swaran J.S. Flora
Keyword(s):  
Heterocyclic Compounds ◽  
Wide Spectrum ◽  
Dna Recognition ◽  
Present Review ◽  
Pharmacological Activities ◽  
Structural Motifs ◽  
Therapeutic Applications ◽  
The Past ◽  
Recent Advances

Nitrogen-containing heterocycles are one of the most common structural motifs in approximately 80% of the marketed drugs. Of these, benzimidazoles analogues are known to elicit a wide spectrum of pharmaceutical activities such as anticancer, antibacterial, antiparasitic, antiviral, antifungal as well as chemosensor effect. Based on the benzimidazole core fused heterocyclic compounds, crescent-shaped bisbenzimidazoles were developed which provided an early breakthrough in the sequence-specific DNA recognition. Over the years, a number of functional variations in the bisbenzimidazole core have led to the emergence of their unique properties and established them as versatile ligands against several classes of pathogens. The present review provides an overview of diverse pharmacological activities of the bisbenzimidazole analogues in the past decade with a brief account of its development through the years.

Recent advances in storage and flooding theory

1969 ◽  
Vol 1 (1) ◽  
pp. 90-110 ◽  
Author(s):  
J. Gani
Keyword(s):  
Queueing Theory ◽  
Applied Probability ◽  
The Past ◽  
Continuous Flows ◽  
Recent Advances ◽  
A Minor ◽  
Queueing Processes ◽  
Theory Of Storage ◽  
Storage Processes

The theory of storage processes, originally formulated by Moran [1] in 1954, has developed in the past fourteen years into a minor subfield of Applied Probability, closely allied to queueing theory. While dam models with discrete inputs are analogous to queueing processes, the essentially continuous nature of water inflows has distinguished generalized storage processes from queues. Indeed, some of the most complex of storage problems have arisen in the case of continuous flows.

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