A case of CADASIL (cerebral autosomal dominant arteriopathy with subcortical infarcts and lekoencephalopathy) with Notch 3 (Arg169Cys) mutation and typical granular osmiophilic materials in peripheral small arteries]

We report a 64-year-old Japanese woman with recurrent ischemic strokes and progressive dementia without any cardiovascular risk factors. Her first stroke was at 45 years old, and she has a family history of ischemic strokes compatible with an autosomal dominant trait. Marked leukoaraiosis and multiple lacunar infarcts were shown on brain MR images, and no atherosclerotic changes were observed in her extra- and intra-cranial arteries by cervical arterial echography and intracranial MR angiography. Excluded other inherited or metabolic diseases causing leukodystrophy by examination of her blood samples, her disease was diagnosed as CADASIL (cerebral autosomal dominant arteriopathy with subcortical infarcts and lekoencephalopathy). We demonstrated granular osmiophilic materials (GOM) on the wall of small arteries from a biopsied peripheral nerve tissue specimen and detected a mutation Arg169Cys of Notch 3 gene. Many CADASIL patients have been reported and over 28 kinds of mutations of the Notch 3 were identified in western countries, while few CADASIL patients have been reported in Japanese people. Among them, eleven CADASIL families have been reported and only five mutations (Arg133Cys, Cys174Phe, Arg213Lys, Arg90Cys and Arg141Cys) have been determined so far. The mutation of Notch 3 in our patient was determined as Arg169Cys, and this is the first report on a Japanese patient with CADASIL due to this mutation.     

Altered mRNA splicing of the skeletal muscle ryanodine receptor and sarcoplasmic/endoplasmic reticulum Ca2+-ATPase in myotonic dystrophy type 1

Myotonic dystrophy type 1 (DM1) is a debilitating multisystemic disorder caused by a CTG repeat expansion in the DMPK gene. Aberrant splicing of several genes has been reported to contribute to some symptoms of DM1, but the cause of muscle weakness in DM1 and elevated Ca2+ concentrations in cultured DM muscle cells is unknown. Here, we investigated the alternative splicing of mRNAs of two major proteins of the sarcoplasmic reticulum, the ryanodine receptor 1 (RyR1) and sarcoplasmic/endoplasmic reticulum Ca2+-ATPase (SERCA) 1 or 2. The fetal variants, ASI(-) of RyR1 which lacks residue 3481-3485, and SERCA1b which differs at the C-terminal were significantly increased in skeletal muscles from DM1 patients and the transgenic mouse model of DM1 (HSA(LR)). In addition, a novel variant of SERCA2 was significantly decreased in DM1 patients. The total amount of mRNA for RyR1, SERCA1 and SERCA2 in DM1 and the expression levels of their proteins in HSA(LR) mice were not significantly different. However, heterologous expression of ASI(-) in cultured cells showed decreased affinity for [3H]ryanodine but similar Ca2+ dependency, and decreased channel activity in single-channel recording when compared with wild-type (WT) RyR1. In support of this, RyR1-knockout myotubes expressing ASI(-) exhibited a decreased incidence of Ca2+ oscillations during caffeine exposure compared with that observed for myotubes expressing WT-RyR1. We suggest that aberrant splicing of RyR1 and SERCA1 mRNAs might contribute to impaired Ca2+ homeostasis in DM1 muscle.     

Two types of quasi-liquid layers on ice crystals are formed kinetically

Surfaces of ice are covered with thin liquid water layers, called quasi-liquid layers (QLLs), even below their melting point (0 °C), which govern a wide variety of phenomena in nature. We recently found that two types of QLL phases appear that exhibit different morphologies (droplets and thin layers) [Sazaki G. et al. (2012) Proc Natl Acad Sci USA 109(4):1052−1055]. However, revealing the thermodynamic stabilities of QLLs remains a longstanding elusive problem. Here we show that both types of QLLs are metastable phases that appear only if the water vapor pressure is higher than a certain critical supersaturation. We directly visualized the QLLs on ice crystal surfaces by advanced optical microscopy, which can detect 0.37-nm-thick elementary steps on ice crystal surfaces. At a certain fixed temperature, as the water vapor pressure decreased, thin-layer QLLs first disappeared, and then droplet QLLs vanished next, although elementary steps of ice crystals were still growing. These results clearly demonstrate that both types of QLLs are kinetically formed, not by the melting of ice surfaces, but by the deposition of supersaturated water vapor on ice surfaces. To our knowledge, this is the first experimental evidence that supersaturation of water vapor plays a crucially important role in the formation of QLLs.Ice is one of the most abundant materials on Earth, and its surfaces are covered with thin liquid water layers even below their melting point (0 °C) (1–4). Such thin liquid water layers are called “quasi-liquid layers” (QLLs). Because QLLs govern the surface properties of ice just below the melting point, it is well acknowledged that surface melting of ice governs a wide variety of phenomena, such as electrification of thunderclouds (4, 5), regelation (4, 6), frost heave (4, 7), conservation of foods, ice skating (1, 8), preparation of a snowman (1), and growth of ice crystals (2, 4). Therefore, it is essential to understand the surface melting of ice crystals at the molecular level.After Michael Faraday proposed the existence of QLLs in 1842 (1), many studies experimentally confirmed the formation of QLLs by various methods (

Safety and efficacy of metallic stent for unresectable distal malignant biliary obstruction in elderly patients

AIM To study the safety of insertion of metallic stents in elderly patients with unresectable distal malignant biliary obstruction.METHODS Of 272 patients with unresectable distal malignant biliary obstruction, 184 patients under the age of 80 were classified into Group A, and 88 subjects aged 80 years or more were classified into Group B. The safety of metallic stent insertion, metal stent patency period, and the obstruction rate were examined in each group.RESULTS In Group B, patients had a significantly worse per-formance status, high blood pressure, heart disease, cerebrovascular disease, and dementia; besides the rate of patients orally administered antiplatelet drugs or anticoagulants tended to be higher(P 0.05). Metallic stents were successfully inserted in all patients. The median patency period was 265.000 ± 26.779(1-965) d; 252.000 ± 35.998(1-618) d in Group A and 269.000 ± 47.885(1-965) d in Group B, with no significant difference between the two groups. Metallic stent obstruction occurred in 82 of the 272(30.15%) patients; in 53/184(28.80%) patients in Group A and in 29/88(32.95%) of those in Group B, showing no significant difference between the two groups. Procedural accidents due to metal stent insertion occurred in 24/272(8.8%) patients; in 17/184(9.2%) of patients in Group A and in 7/88(8.0%) of those in Group B, with no significant difference between the two groups, either.CONCLUSION These results suggested that metallic stents can be safely inserted to treat unresectable distal malignant biliary obstruction even in elderly patients aged 80 years or more.     

Extracts of Musa basjoo induce growth inhibition and changes in the protein expression of cell cycle control molecules in human colorectal cancer cell lines

Musa basjoo (MB) is a species of the banana plant belonging to the genus Musa that has been used as a folk medicine. However, evidence-based biological activities and the molecular mechanism of action of MB are unknown. Thus, the aim of the present study was to examine whether the crude dried leaf extracts of MB inhibit the growth of colorectal (HT29 and HCT116) and other types (HepG2, MCF-7 and PC-3) of human cancer cell lines. Crude extracts of MB inhibited the growth of cells with IC₅₀ values of 136 µg/ml (acetone extract, HT29), 51 µg/ml (acetone extract, HCT116), 45 µg/ml (acetone extract, HepG2), 40 µg/ml (acetone extract, MCF-7), 29 µg/ml (acetone extract, PC-3), 175 µg/ml (methanol extract, HT29), 137 µg/ml (methanol extract, HCT116), 102 µg/ml (methanol extract, HepG2), 85 µg/ml (methanol extract, MCF-7), and 85 µg/ml (methanol extract, PC-3) in colony formation assays, and 126 µg/ml (acetone extract, HT29), 68 µg/ml (acetone extract, HCT116), 260 µg/ml (methanol extract, HT29), and 216 µg/ml (methanol extract, HCT116) in MTT assays. Thin layer chromatography analysis revealed the potential existence of aromatic compounds in the acetone extract of MB. Flow cytometric analysis indicated that the percentage of cells in G1 increased, and this was associated with a concomitant decrease of cells in the S and/or G2-M phases of the cell cycle. When colorectal cancer cells were treated with acetone extract of MB, there was a marked decrease in the levels of expression of the cyclin D1, cyclin E, cdk2 and cdk4 proteins and a marked increase in the levels of the expression of the p21^CIP1, p27^KIP1, and p53 proteins, but those of apoptosis-associated protein PARP did not change. There was a tendency for acetone extract of MB to inhibit xenograft tumor growth in mice. Collectively, the crude extracts of MB contain active components that exert growth inhibition of human cancer cells. This is the first systematic study of the anticancer activity of MB and may broaden insights into the possible clinical approach of specific herbal medicines.