New insights into the pathogenesis of autosomal-dominant cutis laxa with report of five ELN mutations

Autosomal dominant cutis laxa (ADCL) is characterized by a typical facial appearance and generalized loose skin folds, occasionally associated with aortic root dilatation and emphysema. We sequenced exons 28-34 of the ELN gene in five probands with ADCL features and found five de novo heterozygous mutations: c.2296_2299dupGCAG (CL-1), c.2333delC (CL-2), c.2137delG (CL-3), c.2262delA (monozygotic twin CL-4 and CL-5), and c.2124del25 (CL-6). Four probands (CL-1,-2,-3,-6) presented with progressive aortic root dilatation. CL-2 and CL-3 also had bicuspid aortic valves. CL-2 presented with severe emphysema. Electron microscopy revealed elastic fiber fragmentation and diminished dermal elastin deposition. RT-PCR studies showed stable mutant mRNA in all patients. Exon 32 skipping explains a milder phenotype in patients with exon 32 mutations. Mutant protein expression in fibroblast cultures impaired deposition of tropoelastin onto microfibril-containing fibers, and enhanced tropoelastin coacervation and globule formation leading to lower amounts of mature, insoluble elastin. Mutation-specific effects also included endoplasmic reticulum stress and increased apoptosis. Increased pSMAD2 staining in ADCL fibroblasts indicated enhanced transforming growth factor beta (TGF-β) signaling. We conclude that ADCL is a systemic disease with cardiovascular and pulmonary complications, associated with increased TGF-β signaling and mutation-specific differences in endoplasmic reticulum stress and apoptosis.     

Imaging of elasticity distribution in arterial wall by transcutaneous ultrasound and electronic staining

Knowledge of the physical properties of atherosclerotic plaque is essential when evaluating its vulnerability in a clinical setting. Such knowledge, however, is still difficult to obtain with the various approaches developed to date. This paper describes a novel noninvasive method (phased tracking method) for measuring minute change in thickness of each of the multiple layers of the arterial wall during one cardiac cycle. Such minute change in thickness less than 100 microns of the arterial wall cannot be measured by conventional ultrasound B-mode or M-mode images. A method for evaluation of the regional elastic modulus in the circumference direction, E theta, from the resultant change in wall thickness is also described. This method was applied to in vivo experiments in subjects with hyperlipemia and normal subjects. The spatial distribution of the regional elastic moduli, E theta, was evaluated for the carotid atherosclerotic plaques. By comparing the pathological findings with the distribution of elasticity, average elasticity of lipid and that of a mixture of smooth muscle and collagen fiber could be determined. Based on these reference parameters, each point was statistically categorized as lipid, mixture, or other. Thus, the plaque was electronically stained using transcutaneous ultrasound. By applying this method to the common carotid arteries, the presence of thin collagen fiber was clarified along the arterial axis for normal subjects, while soft inclusion of lipid was found for every plaque in subjects with hyperlipidemia. This novel method offers potential as a diagnostic technique for detection of plaque vulnerability with high spatial resolution.     

Pancreatoblastoma with marked elevation of serum alpha-fetoprotein

Summary The autopsy findings in a pancreatoblastoma in a 7-year-old Japanese girl is reported. The tumour was in the head and body of the pancreas, and was associated with diffuse carcinomatous peritonitis and hepatic and pulmonary metastases. There was marked elevation (more than 10000 ng/ml) of serum alpha-fetoprotein (AFP). Histopathologically the tumour was composed of solid epithelial elements with fibrous stroma, showing acinar arrangement, squamoid clusters and tubular structures. The epithelial elements contained numerous fine PAS positive granules in the cytoplasm. Immunocytochemical results suggested epithelial differentiation with positivity to alpha-1-antitrypsin (AAT), keratin, CA19-9, and AFP. No endocrine elements were recognized. Characteristic feature of this tumour are discussed and compared with prevoius reports.     

Immunohistochemical Investigation of Vimentin, Neuron-specific Enolase, α1-antichymotrypsin and α1-antitrypsin in Adenoid Cystic Carcinoma of the Salivary Gland

Fifty-four adenoid cystic carcinomas (ACC) arising in major and minor salivary glands as well as in normal salivary glands were studied by immunohistochemistry for the presence of vimentin, neuron specific enolase (NSE), α₁-antichymotrypsin (α₁-ACT) and α₁-_- antitrypsin (α₁-_- AT). Five patterns of histological differentiation were found in ACC, and for the cellular components of each, it was possible to establish a special immunohistochemical profile. In ACC, vimentin-positive cells were observed in the outer tubular, cyst-lining and small angular cells. NSE was positive in the myoepithelial cells of normal salivary gland. Neoplastic cells of ACC showed NSE positivity mainly in the small angular cells and partly in the duct luminal cells. α₁-ACT was localized in the intercalated duct cells and serous acinar cells of normal salivary gland, and in the duct luminal cells of ACC. α₁-AT could not be detected in any of the epithelial cells of normal salivary gland. In ACC, eosinophilic hyaline material in the cribriform spaces was positive for α₁-AT, but no positivity was demonstrated in tumor cells. The present study showed that there are at least two populations of tumor cells in ACC: duct luminal cells that express α₁-ACT, thus indicating their ductal character, and small angular cells that express vimentin, characteristic of non-luminal cells. Moreover, our results indicate that α₁-AT is a useful marker of basement membrane-like material.     

Cysteamine-induced duodenal ulcer and the hepatoduodenal branch of the vagus nerve

We investigated the role of the autonomic nervous system in gastric acid secretion, somatostatin concentration and PAS-positive mucus production in Brunner’s glands in cysteamine-induced duodenal ulcer. Vagotomized rats were used. No ulcers occurred in the groups with vagotomies of the hepatoduodenal, truncal or gastric branches after cysteamine administration. However, in the hepatoduodenal branch vagotomized group, there was an increases in gastric acid secretion after cysteamine administration. A similar increase was observed in the control group, but the decreases in somatostatin concentration and PAS-positive mucus seen in the control group were not found in the hepatoduodenal vagotomized group. These results suggest that the hepatoduodenal branch of the vagus nerve might play an important role in the ulcerogenic process of cysteamine-induced duodenal ulcer.     

Cholinergic dysregulation produced by selective inactivation of the dystonia-associated protein torsinA

DYT1 dystonia, a common and severe primary dystonia, is caused by a 3-bp deletion in TOR1A which encodes torsinA, a protein found in the endoplasmic reticulum. Several cellular functions are altered by the mutant protein, but at a systems level the link between these and the symptoms of the disease is unclear. The most effective known therapy for DYT1 dystonia is the use of anticholinergic drugs. Previous studies have revealed that in mice, transgenic expression of human mutant torsinA under a non-selective promoter leads to abnormal function of striatal cholinergic neurons. To investigate what pathological role torsinA plays in cholinergic neurons, we created a mouse model in which the Dyt1 gene, the mouse homolog of TOR1A, is selectively deleted in cholinergic neurons (ChKO animals). These animals do not have overt dystonia, but do have subtle motor abnormalities. There is no change in the number or size of striatal cholinergic cells or striatal acetylcholine content, uptake, synthesis, or release in ChKO mice. There are, however, striking functional abnormalities of striatal cholinergic cells, with paradoxical excitation in response to D2 receptor activation and loss of muscarinic M2/M4 receptor inhibitory function. These effects are specific for cholinergic interneurons, as recordings from nigral dopaminergic neurons revealed normal responses. Amphetamine stimulated dopamine release was also unaltered. These results demonstrate a cell-autonomous effect of Dyt1 deletion on striatal cholinergic function. Therapies directed at modifying the function of cholinergic neurons may prove useful in the treatment of the human disorder.     

Alteration of autophagosomal proteins (LC3, GABARAP and GATE-16) in Lewy body disease

Macroautophagy is a dynamic process whereby cytoplasmic molecules are sequestered within autophagosomes. Based on amino acid similarity, there exist two groups of mammalian autophagy-related gene (Atg) 8 homologues [microtubule-associated protein 1 light chain 3 (LC3) and γ-aminobutyric-acid type A receptor associated proteins (GABARAPs)], which play essential role in autophagosomal formation. Despite recent progress in studies on LC3, the other Atg8 homologues remain to be poorly understood, especially in pathological condition. In this study, we determined whether Atg8 homologues are affected in Lewy body disease, including Parkinson's disease (PD) and dementia with Lewy bodies (DLB). Our findings indicated that biochemical and pathological properties of LC3 were altered and that the level of LC3 was increased in an insoluble fraction from the brain of patients with DLB, whereas the level of GABARAPs was decreased in DLB. Furthermore, immunohistochemical staining revealed that both LC3 and GABARAPs were localized in Lewy bodies in PD and DLB. These findings suggest that autophagic function is impaired through alteration of Atg8 homologues in Lewy body disease.     

Optimal timing of contrast enhancement in coronary CT angiography using the Bolus-tracking method

Negative product value for coronary artery disease is 98% to 99%. Therefore, the number of unnecessary cardiac catheterization procedures is reduced as the usefulness of CT systems for examination of the coronary arteries improves. In the bolus-tracking method, in which an ROI is placed in the ascending aorta to trigger scanning, scanning may not be performed at the optimal time of contrast enhancement depending on the patient. In addition to identifying the causes of this problem, we have developed a new method in which ROIs are placed in the right ventricle and left atrium to trigger scanning when the concentrations of contrast medium in the right ventricle and left atrium become equal. The two methods were then compared and evaluated. In the scan method, in which an ROI is placed in the ascending aorta, the reason for non-optimal scan timing is considered to be that the time required for contrast medium injected via an antecubital vein to reach the heart varies depending on the individual patient(approximately 3 times the variation of our method)followed by a delay of approximately 5 seconds between the scan trigger time and the actual scan start time. In the scan method in which scanning is triggered when the concentrations of contrast medium in the right ventricle and left atrium become equal, scanning can be performed at the time of peak enhancement regardless of differences in the time required for the injected contrast medium to reach the target region or differences in the injection rate, demonstrating the usefulness of this method.     

Pulse wave velocity can predict hemodynamic responses to induction of anesthesia and tracheal intubation

BACKGROUND: The degree of aortic stiffness can be evaluated by noninvasive measurement of pulse wave velocity (PWV). We investigated hemodynamic responses to induction of anesthesia and tracheal intubation, and hypothesized that preoperative measurement of PWV might predict these responses. METHODS: PWV was measured before operation by using automatic PWV measurement device. Patients were anesthetized with fentanyl (1 microg x kg(-1)) and propofol (target controlled infusion at 2.5 microg x ml(-1)), and tracheal intubation was facilitated with vecuronium (1.5 mg x kg(-1)). Hemodynamic data were recorded from the start of anesthesia to 5 minutes after the tracheal intubation. RESULTS: Twenty patients completed the study. There was a significant correlation between PWV and percent changes in systolic blood pressure during anesthesia induction. However, a significant correlation between PWV and percent changes in systolic blood pressure after tracheal intubation was found only in the patients without antihypertensive medications. CONCLUSIONS: Preoperative PWV measurement was useful to predict hemodynamic responses to induction of anesthesia and tracheal intubation.