Circulatory miRNAs are promising biomarkers. The feasibility of using miRNA from dried blood spots (DBS) was investigated using newborn screening cards from patients with cholestasis-lymphedema ...syndrome (Aagenaes syndrome) and controls.
Total amount of miRNA and specific miRNAs from DBS were analyzed. miRNA was also obtained from newborn screening cards in patients with cholestasis-lymphedema syndrome/Aagenaes syndrome and in healthy newborns.
No differences in miRNA concentrations were found between multispotted samples and samples with one single drop of blood and between central and peripheral punches. Ten repeated freeze-thaw cycles did not significantly change miRNA levels from controls. miR-299 (1.73-fold change, p = 0.034) and miR-365 (1.46-fold change, p = 0.011) were upregulated and miR-30c (0.72-fold change, p = 0.0037), miR-652 (0.85-fold change, p = 0.025), and miR-744 (0.72-fold change, p = 0.0069) were downregulated in patients with Aagenaes syndrome at birth compared to controls.
miRNAs were not affected by multispotting or punch location and were stable throughout repeated freeze-thaw cycles. miRNA in dried blood spots could be used to detect differential expression of miRNA in newborns with Aagenaes syndrome and healthy controls in newborn screening cards. Dried blood spots may be a useful source to explore circulating miRNA as biomarkers.
Circulating miRNAs can be useful biomarkers. miRNAs from dried blood spots were not affected by multispotting or punch location and were stable throughout repeated freeze-thaw cycles. Discrimination between patients and controls are allowed even with few individuals. Early after birth, patients with cholestasis-lymphedema syndrome exhibit miRNA profiles associated with liver fibrosis. This study demonstrated that newborn screening cards may be a useful source for studying miRNA as the technical variability is smaller than biological variation.
Abstract
The lack of physiological parity between 2D cell culture and in vivo culture has led to the development of more organotypic models, such as organoids. Organoid models have been developed for ...a number of tissues, including the liver. Current organoid protocols are characterized by a reliance on extracellular matrices (ECMs), patterning in 2D culture, costly growth factors and a lack of cellular diversity, structure, and organization. Current hepatic organoid models are generally simplistic and composed of hepatocytes or cholangiocytes, rendering them less physiologically relevant compared to native tissue. We have developed an approach that does not require 2D patterning, is ECM independent, and employs small molecules to mimic embryonic liver development that produces large quantities of liver-like organoids. Using single-cell RNA sequencing and immunofluorescence, we demonstrate a liver-like cellular repertoire, a higher order cellular complexity, presenting with vascular luminal structures, and a population of resident macrophages: Kupffer cells. The organoids exhibit key liver functions, including drug metabolism, serum protein production, urea synthesis and coagulation factor production, with preserved post-translational modifications such as N-glycosylation and functionality. The organoids can be transplanted and maintained long term in mice producing human albumin. The organoids exhibit a complex cellular repertoire reflective of the organ and have de novo vascularization and liver-like function. These characteristics are a prerequisite for many applications from cellular therapy, tissue engineering, drug toxicity assessment, and disease modeling to basic developmental biology.
Purpose
Patients with Fontan circulation are at risk of developing hepatic fibrosis/cirrhosis. The mechanisms and disease development are unclear and early secondary liver cancer is a concern. This ...study will describe hepatic imaging findings in a national cohort of adolescents with Fontan circulation.
Methods
The patients prospectively underwent abdominal contrast enhanced magnetic resonance imaging (MRI) including diffusion-weighted imaging. Images were assessed for criteria of fibrosis
/
cirrhosis including characterization of hepatic nodules. These nodules were in addition, assessed by ultrasonography (US). Nodules ≥ 1 cm were investigated and monitored to evaluate malignant transformation. Clinical and hepatic serological data were recorded.
Results
Forty-six patients, median age of 16.5 years (15.4–17.9 years) were enrolled. All patients underwent US examination and MRI was performed in 35/46 patients. On MRI, 60% had hepatomegaly and 37% had signs of fibrosis/cirrhosis. Seven patients had together 13 nodules ≥ 1 cm in diameter. Only 4/13 (17%) where seen on US. Nodules had variable MRI signal characteristics including hepatobiliary contrast enhancement and two nodules revealed portal venous phase ‘wash-out’ on the first examination. No further imaging signs of malignancy were revealed during the follow-up period of median 24.4 (7–42) months.
Conclusion
The majority of adolescents with Fontan circulation had imaging findings of fibrosis/cirrhosis of varying severity. US had low detection rate of hepatic nodules compared to MRI. The imaging work-up before transition to adult cardiology care did not reveal findings suggestive of malignancy. However, the high prevalence of Fontan-associated liver disease calls for surveillance strategies even in childhood.
Background
Children with Fontan circulation are at risk of developing hepatic fibrosis/cirrhosis. Reliable noninvasive monitoring techniques are lacking or under development.
Objective
To investigate ...surrogate indicators of hepatic fibrosis in adolescents with Fontan circulation by evaluating hepatic magnetic resonance (MR) T1 mapping and extracellular volume fraction measurements compared to US shear-wave elastography.
Materials and methods
We analyzed hepatic native T1 times and extracellular volume fractions with modified Look-Locker inversion recovery. Liver stiffness was analyzed with shear-wave elastography. We compared results between 45 pediatric patients ages 16.7±0.6 years with Fontan circulation and 15 healthy controls ages 19.2±1.2 years. Measurements were correlated to clinical and hemodynamic data from cardiac catheterization.
Results
MR mapping was successful in 35/45 patients, revealing higher hepatic T1 times (774±44 ms) than in controls (632±52 ms;
P
<0.001) and higher extracellular volume fractions (47.4±5.0%) than in controls (34.6±3.8%;
P
<0.001). Liver stiffness was 1.91±0.13 m/s in patients vs. 1.20±0.10 m/s in controls (
P
<0.001). Native T1 times correlated with central venous pressures (r=0.5,
P
=0.007). Native T1 was not correlated with elastography in patients (r=0.2,
P
=0.1) or controls (r = −0.3,
P
=0.3). Extracellular volume fraction was correlated with elastography in patients (r=0.5,
P
=0.005) but not in controls (r=0.2,
P
=0.6).
Conclusion
Increased hepatic MR relaxometry and shear-wave elastography values in adolescents with Fontan circulation suggested the presence of hepatic fibrosis or congestion. Central venous pressure was related to T1 times. Changes were detected differently with MR relaxometry and elastography; thus, these techniques should not be used interchangeably in monitoring hepatic fibrosis.
The prevailing concept is that gestational alloimmune liver disease (GALD) is caused by maternal antibodies targeting a currently unknown antigen on the liver of the fetus. This leads to deposition ...of complement on the fetal hepatocytes and death of the fetal hepatocytes and extensive liver injury. In many cases, the newborn dies. In subsequent pregnancies early treatment of the woman with intravenous immunoglobulin can be instituted, and the prognosis for the fetus will be excellent. Without treatment the prognosis can be severe. Crucial improvements of diagnosis require identification of the target antigen. For this identification, this work was based on two hypotheses: 1. The GALD antigen is exclusively expressed in the fetal liver during normal fetal life in all pregnancies; 2. The GALD antigen is an alloantigen expressed in the fetal liver with the woman being homozygous for the minor allele and the father being, most frequently, homozygous for the major allele. We used three different experimental approaches to identify the liver target antigen of maternal antibodies from women who had given birth to a baby with the clinical GALD diagnosis: 1. Immunoprecipitation of antigens from either a human liver cell line or human fetal livers by immunoprecipitation with maternal antibodies followed by mass spectrometry analysis of captured antigens; 2. Construction of a cDNA expression library from human fetal liver mRNA and screening about 1.3 million recombinants in Escherichia coli using antibodies from mothers of babies diagnosed with GALD; 3. Exome/genome sequencing of DNA from 26 presumably unrelated women who had previously given birth to a child with GALD with husband controls and supplementary HLA typing. In conclusion, using the three experimental approaches we did not identify the GALD target antigen and the exome/genome sequencing results did not support the hypothesis that the GALD antigen is an alloantigen, but the results do not yield basis for excluding that the antigen is exclusively expressed during fetal life., which is the hypothesis we favor.
Biliary atresia is the most common reason for newborn cholestasis and pediatric liver transplantation. Even after normalization of serum bilirubin after portoenterostomy, most patients require liver ...transplantation by adulthood due to expanding fibrosis. We addressed contemporary outcomes of biliary atresia in the Nordic countries.
Data on center and patients characteristics, diagnostic practices, surgical treatment, adjuvant medical therapy after portoenterostomy, follow-up and outcomes were collected from all the Nordic centers involved with biliary atresia care during 2005–2016.
Of the 154 patients, 148 underwent portoenterostomy mostly by assigned surgical teams at median age of 64 (interquartile range 37–79) days, and 95 patients (64%) normalized their serum bilirubin concentration while living with native liver. Postoperative adjuvant medical therapy, including steroids, ursodeoxycholic acid and antibiotics was given to 137 (93%) patients. Clearance of jaundice associated with young age at surgery and favorable anatomic type of biliary atresia, whereas annual center caseload >3 patients and diagnostic protocol without routine liver biopsy predicted early performance of portoenterostomy. The cumulative 5-year native liver and overall survival estimate was 53% (95% CI 45–62) and 88% (95% CI 83–94), respectively. Portoenterostomy age <65days and annual center caseload >3 patients were predictive for long-term native liver survival, while normalization of serum bilirubin after portoenterostomy was the major predictor of both native liver and overall 5-year survival.
The outcomes of biliary atresia in the Nordic countries compared well with previous European studies. Further improvement should be pursued by active measures to reduce patient age at portoenterostomy.
Level II.
Abstract
Background
Oxidation Resistance 1
(
OXR1
) gene is a highly conserved gene of the TLDc domain-containing family. OXR1 is involved in fundamental biological and cellular processes, including ...DNA damage response, antioxidant pathways, cell cycle, neuronal protection, and arginine methylation. In 2019, five patients from three families carrying four biallelic loss-of-function variants in OXR1 were reported to be associated with cerebellar atrophy. However, the impact of OXR1 on cellular functions and molecular mechanisms in the human brain is largely unknown. Notably, no human disease models are available to explore the pathological impact of OXR1 deficiency.
Results
We report a novel loss-of-function mutation in the TLDc domain of the human
OXR1
gene, resulting in early-onset epilepsy, developmental delay, cognitive disabilities, and cerebellar atrophy. Patient lymphoblasts show impaired cell survival, proliferation, and hypersensitivity to oxidative stress. These phenotypes are rescued by TLDc domain replacement. We generate patient-derived induced pluripotent stem cells (iPSCs) revealing impaired neural differentiation along with dysregulation of genes essential for neurodevelopment. We identify that OXR1 influences histone arginine methylation by activating protein arginine methyltransferases (PRMTs), suggesting OXR1-dependent mechanisms regulating gene expression during neurodevelopment. We model the function of OXR1 in early human brain development using patient-derived brain organoids revealing that OXR1 contributes to the spatial–temporal regulation of histone arginine methylation in specific brain regions.
Conclusions
This study provides new insights into pathological features and molecular underpinnings associated with OXR1 deficiency in patients.
The aim of the present study was to assess whether the complication rate after ultrasound-guided percutaneous liver biopsies in children is affected by how frequently the procedure is performed by ...the operator.
Medical charts and ultrasound descriptions of 311 ultrasound-guided percutaneous liver biopsy procedures performed by 18 radiologists at a single center from 2000 to 2011 were reviewed. Postbiopsy ultrasound the following day was performed after 97% of the procedures.
There were no differences in the procedure-associated rate of major bleeding incidents (2.2% vs 0.8%, P = 0.38), minor bleeding incidents (15.2% vs 10.2%, P = 0.31), or abdominal pain (13.0% vs 10.6%, P = 0.61) among operators who performed ≤10 procedures and those who performed >10 procedures during the study period. A higher rate of minor bleeding incidents were recorded after liver biopsy when operators had performed <10 biopsies compared with operators who had performed >20 pediatric liver biopsies during the study period (odds ratio 3.4 1.3-9.1, P = 0.02). No association between the number of biopsies performed by the operator during the 2 years preceding the date of the biopsy and complications was found.
Major complications are infrequent after pediatric liver biopsies and no relation between operator experience and major complications was found. We found a significant, but minor, effect of operator procedure frequency on the rate of minor bleeding incidents after ultrasound-guided pediatric liver biopsies.
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