Noninvasive acoustic radiation force impulse (ARFI) elastography for assessing the severity of fibrosis in the post-operative patients with biliary atresia.

PURPOSE: Liver biopsy (LB) is still considered the "gold standard" for hepatological evaluation, but recently noninvasive methods have attempted to replace this invasive procedure. Recently, acoustic radiation force impulse (ARFI) imaging has been developed as a noninvasive modality to evaluate the stiffness of tissues. ARFI imaging theoretically measures liver stiffness of all the segments independently. The aim of this study was to determine whether ARFI elastography is a reliable method for predicting the severity of fibrosis in the post-operative patients with biliary atresia. METHODS: ARFI elastography was performed 21 times in eight patients with biliary atresia over the last 2 years. At the same time, we measured serum hyaluronic acid (H value), which is one of the serum elastic makers, to compare ARFI versus values in these patients. We obtained ARFI versus values as the median of S2 to S8 by three consecutive measurements acquired with a Siemens Acuson S2000 (Siemens Medical Systems, Germany). RESULTS: Histological evaluation of fibrosis is graded from F0 (normal) to F4. The normal H value is under 50 mg/dl. One patient had F0 (H value 29.2 mg/dl), four had F1 (H value 11.5-18.1 mg/dl), one had F3 (H value 61.3 mg/dl), two had F4 (H value 29.2, 112 mg/dl). One patient with F4 whose ARFI versus value (3.56 m/s) was the highest, needed liver transplantation and her liver was cirrhotic. CONCLUSION: These findings suggest that ARFI measurement may be a reliable method for predicting the severity of fibrosis after a Kasai operation.

The usefulness of laryngotracheal separation in the treatment of severe motor and intellectual disabilities.

Intractable aspiration is a life-threatening medical problem in patients with severe motor and intellectual disabilities (SMID). Laryngotracheal separation (LTS) is a surgical procedure for the treatment of intractable aspiration which separates the upper respiratory tract from the digestive tract. We performed LTS for 14 patients with SMID to prevent intractable aspiration, performing two types of operation. The standard diversion procedure connected the upper trachea to the esophagus. The modified diversion includes closure of the proximal trachea and a high tracheostomy, avoiding a tracheoesophageal anastomosis. LTS was performed on 14 patients. Operations performed before the LTS included tracheostomy in four patients, fundoplication in six and gastrostomy in two. A standard diversion was performed in 11 patients and a modified diversion in 3. There were no operative complications. Eleven patients were safely transferred to home-care after their LTS. Twelve patients are still alive and two died some months after operation. One patient died from their primary disease and the other died a tracheo-innominate artery fistula (TIAF). We recently experienced a patient who was at high risk of developing a TIAF. LTS is an effective operation, preventing intractable aspiration in patients with severe motor and intellectual disabilities. The results are similar for the standard or modified diversion procedure with the procedure chosen being related to the initial tracheostomy site. The most serious complication is a lethal TIAF.

Increased occurrence of caspase-dependent apoptosis in unfavorable neuroblastomas.

Neuroblastoma frequently shows spontaneous regression in which two distinct types of programmed cell death, ie, caspase-dependent apoptosis and H-Ras-mediated autophagic degeneration, have been suggested to play a key role. The current study was conducted to determine which of these cell suicide pathways predominated in this tumor regression. Periodic acid-Schiff (PAS) staining and immunostaining for H-Ras and for the full-length and cleaved forms of caspase-3, poly (ADP-ribose) polymerase (PARP), and lamin A were carried out on 55 archival tumor specimens. The incidence of caspase-dependent apoptosis in each tumor was quantified by cleaved lamin A staining and compared with clinicopathologic prognostic factors. Although a recent report has shown that neuroblastic cells undergoing autophagic degeneration were readily detectable by PAS and H-Ras staining, we could not confirm this result in any of our samples with the exception of one tumor. Instead, many of our neuroblastoma samples showed nonspecific PAS and Ras staining in areas of necrosis, suggesting that autophagic "degeneration" indeed corresponds to coagulation necrosis or oncosis. Unexpectedly, the incidence of caspase-dependent apoptosis was significantly correlated with indicators of a poor prognosis in these tumors, including Shimada's unfavorable histology, MYCN amplification, and a higher mitosis-karyorrhexis index, but not with factors related to tumor regression such as clinical stage and mass screening. These results indicate that neither caspase-dependent apoptosis nor autophagic "degeneration" may be involved in spontaneous neuroblastoma regression. This suggests that other mechanisms, perhaps such as tumor maturation, may be responsible for this phenomenon.

Identification of novel human neuronal leucine-rich repeat (hNLRR) family genes and inverse association of expression of Nbla10449/hNLRR-1 and Nbla10677/hNLRR-3 with the prognosis of primary neuroblastomas.

To search for novel prognostic indicators, we previously cloned >2,000 novel genes from primary neuroblastoma (NBL) cDNA libraries and screened for differential expression between the subsets with favorable (stage 1 or 2 with a single copy of MYCN) and unfavorable (stage 3 or 4 with amplification of MYCN) prognosis. From them, we have identified 3 genes of human neuronal leucine-rich repeat protein (NLRR) family: Nbla10449/hNLRR-1, Nbla00061/hNLRR-2/GAC1 and Nbla10677/hNLRR-3. An additional family member, hNLRR-5, was also found by homology search against public database. NLRR family proteins have been proposed to function as a neuronal adhesion molecule or soluble ligand binding receptor like Drosophila toll and slit with multiple domains including 11 sets of extracellular leucine-rich repeat (LRR)-motifs. However, the functional role of the NLRR protein family has been elusive. Our present study shows that hNLRR mRNAs are preferentially expressed in nervous system and/or adrenal gland. In cancer cell lines, hNLRR-1, hNLRR-3 and hNLRR-5 are expressed at high levels in the neural crest-derived cells. Most remarkably, in primary NBLs, hNLRR-1 is significantly expressed at high levels in unfavorable subsets as compared to favorable ones, whereas the expression pattern of hNLRR-3 and hNLRR-5 is the opposite. In order to understand the function of these receptors, we have used newborn mouse superior cervical ganglion (SCG) cells which are dependent on nerve growth factor (NGF) for their survival. Expression of the mouse counterparts of hNLRR-2 and hNLRR-3 is up-regulated after NGF-induced differentiation and down-regulated after NGF depletion-induced apoptosis. On the other hand, expression of hNLRR-1 and hNLRR-5 is inversely regulated in the same system. These results have suggested that the regulation of the hNLRR family genes may be associated with NGF signaling pathway in both SCG cells and neuroblastoma. Our quantitative real-time RT-PCR analysis using 99 primary NBLs has revealed that high levels of hNLRR-1 expression are significantly associated with older age (>1 year, p=0.0001), advanced stages (p=0.0007), low expression of TrkA (p=0.011), and MYCN amplification (p=0.0001), while those of hNLRR-3 expression are significantly correlated with the favorable prognostic indicators. Furthermore, multivariate analysis reveals that expression of hNLRR-1 is an independent prognostic indicator in human neuroblastoma. Thus, our results demonstrate that, despite being members of the same family, hNLRR-1 and hNLRR-3 may share different biological function among the NBL subsets, and that their expression level becomes novel prognostic indicators of NBL.

Neuroblastoma oligo-capping cDNA project: toward the understanding of the genesis and biology of neuroblastoma.

Neuroblastoma (NBL) is a common pediatric cancer originated from the neuronal precursor cells of sympathoadrenal lineage. NBLs show a variety of clinical phenotypes from spontaneous regression to malignant progression with acquirement of resistance to therapy. To understand the molecular mechanism of the genesis, progression, and regression of NBL, we need to identify key molecules determining the neuronal development of sympathoadrenal lineage. To this end, we have performed the NBL cDNA project. It includes (1) mass-cloning of the expressed genes from oligo-capping cDNA libraries derived from primary NBLs with different clinical and biological features; (2) mass-identification of differentially expressed genes between favorable and unfavorable subsets; and (3) molecular and functional analyses of the novel genes, which could be useful prognostic indicators. To date, 10,000 cDNA clones in total, approximately 40% of which contained novel sequences, were randomly picked up and DNA sequenced. We have identified approximately 500 differentially expressed genes between favorable and unfavorable subsets of NBL, among which more than 250 were the genes with unknown function.