Acyl CoA Oxidase 2 (ACOX2) encodes branched-chain acyl-CoA oxidase, a peroxisomal enzyme believed to be involved in the metabolism of branched-chain fatty acids and bile acid intermediates. Deficiency of this enzyme has not been described previously. We report an 8-y-old male with intermittently elevated transaminase levels, liver fibrosis, mild ataxia, and cognitive impairment. Exome sequencing revealed a previously unidentified homozygous premature termination mutation (p.Y69*) in ACOX2. Immunohistochemistry confirmed the absence of ACOX2 expression in the patient’s liver, and biochemical analysis showed marked elevation of intermediate bile acids upstream of ACOX2. These findings define a potentially treatable inborn error of bile acid biosynthesis caused by ACOX2 deficiency.

Vitamin E treatment, in addition to its previously shown beneficial effect by suppressing oxidative stress, may also achieve improvement by reducing IR and PPAR-alpha expression in NASH.

Abnormalities in liver function tests are common in hematopoietic SCT (HSCT) recipients. We retrospectively investigated the role of liver biopsy in determining the cause of elevated liver enzymes and its impact on the management of patients in the post-HSCT setting. A total of 24 consecutive liver biopsies were obtained from 20 patients from September 2003 to December 2007. A definite histopathologic diagnosis was obtained in 91.7% of the biopsies. Iron overload (IO) was found in 75% and GVHD in 54.2% of the patients. The initial clinical diagnosis of GVHD was confirmed in 56.5% and refuted in 43.5% of the allogeneic HSCT recipients. The median number of post transplant transfusions, percent transferrin saturation and ferritin levels were found to be higher in patients who had histologically proven hepatic IO (p1 ¼ 0.007, p2 ¼ 0.003 and p3 ¼ 0.009, respectively). Regression analysis showed a significant correlation between serum ferritin levels and histological grade of iron in the hepatocytes. Our data suggest that hepatic IO is a frequent finding in the post-HSCT setting, which contributes to hepatic dysfunction and it should be considered in the differential diagnosis, particularly in patients with high serum ferritin levels.

Despite advances in the diagnosis and management of idiopathic non-cirrhotic portal hypertension (INCPH), its pathogenesis remains elusive. Insight may be gained from study of early onset familial INCPH, in which Mendelian mutations may account for disease. We performed exome sequencing of 8 subjects from 6 kindreds with onset of portal hypertension of indeterminate etiology during infancy or childhood. Three subjects from two consanguineous families shared the identical rare homozygous p.N46S mutation in DGUOK, a deoxyguanosine kinase required for mitochondrial DNA replication; haplotype sharing demonstrated the mutation in the two families was inherited from a remote common ancestor. All three affected subjects had stable portal hypertension with non-cirrhotic liver disease for 6–16 years of follow-up. This mutation impairs ATP binding and reduces catalytic activity. Loss-of-function mutations in DGUOK have previously been implicated in cirrhosis and liver failure but not in isolated portal hypertension. Interestingly, treatment of patients with HIV infection with the nucleoside analog didanosine is known to cause portal hypertension in a subset of patients and lowers deoxyguanosine kinase levels in vitro; the current findings implicate these effects on deoxyguanosine kinase in the causal mechanism. CONCLUSION: Our findings provide new insight into the mechanisms mediating inherited and acquired non-cirrhotic portal hypertension, expand the phenotypic spectrum of DGUOK deficiency, and provide a new genetic test for a specific cause of INCPH.

No abstract

The role of transforming growth factor beta1 (TGF beta1) in airway remodeling in asthma and chronic obstructive pulmonary disease (COPD) has not been fully described. To evaluate the possible pathogenetic role of TGF beta1 in asthma and COPD, immunohistochemical expression of TGF beta1 was described in bronchial biopsies from patients with asthma and COPD compared with healthy individuals. Twelve subjects with asthma, 13 subjects with COPD, and 10 healthy individuals enrolled in the study. Bronchial biopsies were stained with hematoxylin and eosin and anti-TGF beta1 antibody. As a result, immunoreactive TGF beta1 was mainly localized in association with connective tissue in all groups. The staining intensity was not statistically different among the groups in bronchial epithelium, whereas it was significantly higher in the group of asthma in the submucosa. Because there is evidence showing a significant increase of staining intensity in the submucosa from asthmatics but not from subjects with COPD, we may conclude that TGF beta1 may play a significant role in pathogenesis of asthma but not in COPD.

RDW a new non-invasive marker that can be used to demonstrate the presence of NASH and indicate advanced fibrotic scores.

and corneal antioxidant enzyme activities after refractive corneal surgery AbstractPurpose Refractive corneal surgery induces keratocyte apoptosis and generates reactive oxygen radicals (ROS) in the cornea. The purpose of the present study is to evaluate the correlation between keratocyte apoptosis and corneal antioxidant enzyme activities after different refractive surgical procedures in rabbits. Methods Rabbits were divided into six groups. All groups were compared with the control group (Group 1), after epithelial scraping (Group 2), epithelial scrape and photorefractive keratectomy (PRK) (traditional PRK: Group 3), transepithelial PRK (Group 4), creation of a corneal flap with microkeratome (Group 5) and laserassisted in situ keratomileusis (LASIK, Group 6). Terminal deoxyribonucleotidyl transferase-mediated dUTP-digoxigenin nickend labelling assay (to detect DNA fragmentation in situ) and light microscopy were used to detect apoptosis in rabbit eyes. Glutathione peroxidase (Gpx) and superoxide dismutase (SOD) activities of the corneal tissues were measured with spectrophotometric methods. Results Corneal Gpx and SOD activities decreased significantly in all groups when compared with the control group (PϽ0.05) and groups 2, 3 and 6 showed a significantly higher amount of keratocyte apoptosis (PϽ0.05). Not only a negative correlation was observed between corneal SOD activity and keratocyte apoptosis (cc: ؊0.3648) but Gpx activity also showed negative correlation with keratocyte apoptosis (cc: ؊0.3587). Conclusion The present study illustrates the negative correlation between keratocyte apoptosis and corneal antioxidant enzyme activities. This finding suggests that ROS may be partly responsible for keratocyte apoptosis after refractive surgery.