Bethanechol for neonatal transient gastrointestinal dismotility in two cases of congenital myotonic dystrophy

Although gastrointestinal symptoms are frequently observed in congenital myotonic dystrophy (congenital MD) during early neonatal periods, there are few reports of gastrointestinal smooth muscle involvement and its management. We report two cases with congenital MD treated with bethanechol (0.25 mg/kg/dose 30 min before breast milk, 8 doses/day) for gastrointestinal dismotility. Two patients showed gastrointestinal symptoms characterized by increased gastric residua prior to the next feeding and gasless abdomen with relative gastric dilatation on abdominal X ray. Treatment with bethanechol resolved the gastrointestinal symptoms and allowed increase of daily feeding volume. We speculate that the main pathogenesis of transient gastrointestinal dismotility in neonates with congenital MD is gastroparesis probably due to "maturation arrest" of smooth muscle. Bethanechol may be one of the alternative prokinetic drugs to increase gastric emptying.     

Reliability and validity of the Japanese version of the Dysexecutive Questionnaire (DEX) in Alzheimer's disease: validation of a behavioral rating scale to assess dysexecutive symptoms in Japanese patients with Alzheimer's disease

BACKGROUND: Both executive cognitive dysfunction and behavioral problems contribute to dysexecutive symptoms in daily life. The aim of the present study was to develop a behavior rating scale for assessing dysexecutive symptoms in Japanese patients with AD. METHOD: The Dysexecutive Questionnaire (DEX), devised by Burgess et al. (1998), was used to evaluate 122 Japanese patients with AD. The factor structure, internal consistency, test-retest reliability, and construct validity of the Japanese version of the DEX were then examined. RESULTS: The Japanese version of the DEX demonstrated a good internal reliability and a good test-retest reliability. Factor analysis revealed three factors that were named 'apathy', 'hyperactivity' and 'planning and monitoring process of the purposive action'. The 'apathy' factor of the DEX was significantly correlated with the 'apathy' score of the Neuropsychiatric Inventory (NPI), while 'planning and monitoring process' factor of the DEX was significantly correlated with the total score of the Frontal Assessment Battery (FAB) and the 'hyperactivity' factor of the DEX was significantly correlated with the 'aggression', 'euphoria' and 'disinhibition' scores of the NPI. CONCLUSIONS: The Japanese DEX is a reliable and valid instrument for assessing executive dysfunction conveniently in real life situations of AD patients. While two factors, 'apathy' and 'hyperactivity', were associated with emotional and behavioral changes, the 'planning and monitoring process' was associated with the cognitive executive function in the patients with AD. These findings suggest that both a neuropsychiatric syndrome and cognitive function contribute to the dysexecutive symptoms experienced by AD patients in daily life.     

Estimation of relative microscopic affinity constants of agonists for the active state of the receptor in functional studies on M2 and M3 muscarinic receptors

In prior work, we have shown that it is possible to estimate the product of observed affinity and intrinsic efficacy of an agonist expressed relative to that of a standard agonist simply through the analysis of their respective concentration-response curves. In this report, we show analytically and through mathematical modeling that this product, termed intrinsic relative activity (RA(i)), is equivalent to the ratio of microscopic affinity constants of the agonists for the active state of the receptor. We also compared the RA(i) estimates of selected muscarinic agonists with a relative estimate of the product of observed affinity and intrinsic efficacy determined independently through the method of partial receptor inactivation. There was good agreement between these two estimates when agonist-mediated inhibition of forskolin-stimulated cAMP accumulation was measured in Chinese hamster ovary cells stably expressing the human M(2) muscarinic receptor. Likewise, there was good agreement between the two estimates when agonist activity was measured on the ileum from M(2) muscarinic receptor knockout mice, a convenient assay for M(3) receptor activity. The RA(i) estimates of agonists in the mouse ileum were similar to those estimated at the human M(3) receptor with the exception of 4-(m-chlorophenyl-carbamoyloxy)-2-butynyltrimethylammonium (McN-A-343), which is known to be an M(1)- and M(4)-selective muscarinic agonist. Additional experiments showed that the response to McN-A-343 in the mouse ileum included a non-M(3) muscarinic receptor component. Our results show that the RA(i) estimate is a useful receptor-dependent measure of agonist activity and ligand-directed signaling.     

A female-biased expressed elongase involved in long-chain hydrocarbon biosynthesis and courtship behavior in Drosophila melanogaster

Drosophila melanogaster produces sexually dimorphic cuticular pheromones that are a key component of the courtship behavior leading to copulation. These molecules are hydrocarbons, with lengths of 23 and 25 carbons in males (mainly with one double bond) and 27 and 29 carbons in females (mainly with two double bonds). Here, we describe an elongase gene, eloF, with female-biased expression. The 771-bp ORF encodes a 257-aa protein that shows the highest sequence identity with mouse SSC1 elongase (33%). The activity of the cDNA expressed in yeast was elongation of saturated and unsaturated fatty acids up to C30. RNAi knockdown in Drosophila led to a dramatic modification of female hydrocarbons, with decreased C29 dienes and increased C25 dienes accompanied by a modification of several courtship parameters: an increase in copulation latency and a decrease in both copulation attempts and copulation. Feminization of the hydrocarbon profile in males by using targeted expression of the transformer gene resulted in high expression levels of eloF, suggesting that the gene is under the control of the sex-determination hierarchy. There is no expression of eloF in Drosophila simulans, which synthesize only C23 and C25 hydrocarbons. These results strongly support the hypothesis that eloF is a crucial enzyme for female pheromone biosynthesis and courtship behavior in D. melanogaster.     

Enhanced self-renewal capability in hepatic stem/progenitor cells drives cancer initiation

BACKGROUND & AIMS: Transformed hematopoietic stem/progenitor cells with an enhanced or acquired self-renewal capability function as leukemic stem cells. In a variety of solid cancers, stem/progenitor cells could be also targets of carcinogenesis. However, it remains unclear whether disruption of stem cell function directly contributes to cancer initiation. We sought to elucidate the mechanisms of self-renewal in hepatic stem/progenitor cells and the relation between stem cell function and hepatocarcinogenesis. METHODS: Functional analyses of polycomb-group protein Bmi1 and Wnt/beta-catenin, the molecules that are responsible for the self-renewal capability of many types of stem cells, were conducted in c-Kit(-)CD29(+)CD49f(+/low)CD45(-)Ter-119(-) hepatic stem/progenitor cells using retrovirus- or lentivirus-mediated gene transfer. The tumorigenicity of these cells transduced with the indicated retroviruses was also assessed by transplantation into nonobese diabetic/severe combined immunodeficient mice. RESULTS: Forced expression of Bmi1 and constitutively active beta-catenin mutant similarly promoted the self-renewal of hepatic stem/progenitor cells. The transplantation of Bmi1- or beta-catenin-transduced cells clonally expanded from single hepatic stem/progenitor cells produced tumors, which exhibited the histologic features of combined hepatocellular and cholangiocarcinoma. CONCLUSIONS: These observations imply that the dysregulated self-renewal of hepatic stem/progenitor cells serves as an early event in hepatocarcinogenesis, and they highlight the important roles of Bmi1 and the Wnt/beta-catenin pathway in regulating the self-renewal of normal or cancer stem cells in liver.     

In vitro selection of DNA aptamers that block toxic effects of AGE on cultured retinal pericytes

Microvessels are composed of endothelial cells and pericytes. We have previously shown that advanced glycation end products (AGE) not only inhibit DNA synthesis but also induce apoptosis in cultured retinal pericytes, thereby being involved in pericyte loss, the earliest histopathological hallmark of diabetic retinopathy. Since pericytes play a central role in the maintenance of microvascular homeostasis in the retina, blockade of the harmful effects of AGE on retinal pericytes may become a novel therapeutic strategy for the treatment of diabetic retinopathy. In this study, we selected DNA aptamers directed against AGE in vitro and then examined their cytoprotective effects on AGE-exposed retinal pericytes. We identified 15 DNA aptamers directed against AGE-human serum albumin using combinatorial chemistry techniques in vitro. Structural analysis revealed that they had bulge-loop structures with cytosine-rich sequences. All of the aptamers, but not non-binding control aptamers, were found to inhibit the AGE-induced decrease in DNA synthesis as well as apoptotic cell death in pericytes. Among the selected aptamers, the clone 9 aptamer completely blocked the toxic effects of AGE, and its dissociation constant was 1 micromol/L. These results indicate that DNA aptamers are a useful tool for inhibiting the cytotoxic effects of AGE on cultured retinal pericytes. Our study suggests that blockade of the AGE effects by DNA aptamers may lead to a novel therapeutic strategy for the treatment of diabetic retinopathy.     

Overexpressed cyclo-oxygenase-2 in the background liver is associated with the clinical course of hepatitis C virus-related cirrhosis patients after curative surgery for hepatocellular carcinoma

BACKGROUND: The probable role of cyclo-oxygenase-2 (COX-2) in the development of hepatocellular carcinoma (HCC) in patients with chronic liver diseases has been accepted to be relevant. The purpose of the present study was to determine whether overexpressed COX-2 in the background liver affects the clinical course of hepatitis C virus (HCV)-related cirrhosis patients after curative surgery for HCC. METHODS: Twenty-nine clinical stage I HCC patients with HCV-related cirrhosis, who underwent curative surgery, were enrolled in the present study (22 men and seven women, age range 53-73 years; follow-up period; range 22-159 months, median 61 months). The COX-2 expression in the cirrhotic liver was examined by immunohistochemistry using the avidin-biotin-peroxidase complex technique on paraffin-embedded formalin-fixed tissue. The COX-2 expression was scored, then correlated with monitored alanine aminotransferase (ALT) levels during the follow-up period after surgery, response to alternative therapy aiming to improve elevated ALT levels, and recurrence/survival after surgery. RESULTS: The COX-2 expression scores were significantly higher in the high-ALT group than in the low-ALT group (Mann-Whitney, P = 0.010), and were significantly higher in non-responders to the alternative therapy than in responders (Mann-Whitney, P = 0.028). The higher COX-2 expression in the cirrhotic liver was the significant independent risk factor for residual liver recurrence (Cox multivariate analysis, P = 0.014), but not for survival. CONCLUSIONS: Overexpressed COX-2 in the background liver may play an important role in prolonged acceleration of necroinflammation, resistance to the alternative therapy, and recurrence/new development of HCC in HCV-related cirrhosis patients.