Enantioselective Organocatalyzed Michael Addition of Isobutyraldehyde to Maleimides in Aqueous Media.

Thiourea was introduced into (R,R)-1,2-diphenylethylenediamine as an organocatalyst to promote the reaction between isobutyraldehydes and maleimides. Enantioselective Michael addition reaction was carried out as an eco-friendly method using water as the solvent. As a result of the reaction between isobutyraldehyde and maleimide, ≥97% yield and 99% enantioselectivity were obtained at a low catalyst loading of 0.01 mol%. The solvent effect can be explained by theoretical calculations that indicate the participation of a transition state, in which the CF3 substituent of the catalyst is a hydrogen bond activated by the surrounding water molecules. This discovery enabled the use of low catalyst loading in the organic reactions of chiral substances for pharmaceutical applications. Furthermore, a solvent effect for Michael reaction of the organocatalysts was proposed, and the organic reaction mechanisms were determined through quantum calculations.

MouseNet v2: a database of gene networks for studying the laboratory mouse and eight other model vertebrates.

Laboratory mouse, Mus musculus, is one of the most important animal tools in biomedical research. Functional characterization of the mouse genes, hence, has been a long-standing goal in mammalian and human genetics. Although large-scale knockout phenotyping is under progress by international collaborative efforts, a large portion of mouse genome is still poorly characterized for cellular functions and associations with disease phenotypes. A genome-scale functional network of mouse genes, MouseNet, was previously developed in context of MouseFunc competition, which allowed only limited input data for network inferences. Here, we present an improved mouse co-functional network, MouseNet v2 (available at http://www.inetbio.org/mousenet), which covers 17 714 genes (>88% of coding genome) with 788 080 links, along with a companion web server for network-assisted functional hypothesis generation. The network database has been substantially improved by large expansion of genomics data. For example, MouseNet v2 database contains 183 co-expression networks inferred from 8154 public microarray samples. We demonstrated that MouseNet v2 is predictive for mammalian phenotypes as well as human diseases, which suggests its usefulness in discovery of novel disease genes and dissection of disease pathways. Furthermore, MouseNet v2 database provides functional networks for eight other vertebrate models used in various research fields.

Effects of selective exercise for the deep abdominal muscles and lumbar stabilization exercise on the thickness of the transversus abdominis and postural maintenance.

[Purpose] The purpose of this study was to examine the effects of selective exercise for the deep abdominal muscles (SEDA) and lumbar stabilization exercise (LSE) on the thickness of the transversus abdominis and postural maintenance on an unstable base of support. [Subjects and Methods] The subjects of this study were 20 male and 10 female adults in their 20s without lumbar pain. They were equally and randomly assigned to a SEDA group and a LSE group. The thickness of the transversus abdominis was measured using ultrasound imaging during rest and drawing-in. The thickness of the transversus abdominis was measured when subjects raised their right and left legs while lying on a Swiss ball. [Results] Initially, there were no differences between the two groups. After the intervention, significant differences were observed in all parameters. A significant interaction between group and period was not found for any parameters. [Conclusion] In conclusion, both SEDA and LSE thickened the transversus abdominis, which is a deep abdominal muscle, thereby adjusting posture, and stabilizing the trunk. These exercises increased the thickness of the deep abdominal muscles. They are important exercises for improving the stability of athletes or patients who need postural adjustment.

Relationship between diabetes mellitus with dural arteriovenous fistula.

INTRODUCTION: The aetiology of dural arteriovenous fistula (DAVF) is not well known, but it has been suggested that abnormality in angiogenesis plays a pathological role. Abnormality in angiogenesis is also involved in diabetes mellitus (DM). The purpose of this study was to quantify the relation between DAVF and DM in a Korean population. METHODS: Medical records of 192 patients with DAVF between 2002 and 2011 were reviewed. Age, sex and the presence of DM, hypertension, hyperlipidaemia, stroke, coronary artery disease and cancers were compared between DAVF and control subjects. Data for control were obtained from the Korean National Health and Nutrition Examination Survey. The relationship of DM and DAVF location, presenting symptoms (benign vs. aggressive) and classification (Borden and Geibprasert) were assessed using the Pearson's chi-square test. RESULTS: Prevalence of DM was higher in DAVF patients (19.8 %) than in controls (9.5 %; p = 0.004). Univariate analysis showed that DM (odds ratio (OR), 2.356; 95 % confidence interval (CI), 1.634-3.399; p < 0.001) and age (OR, 1.022; 95 % CI, 1.012-1.032; p < 0.001) increased the odds of DAVF. This was supported by multivariate analysis (DM: OR, 2.092; 95 % CI, 1.391-3.145; p = 0.0004 and Age: OR, 1.021; 95 % CI, 1.009-1.033; p = 0.001). When these analyses were repeated after stratification by sex, there was no relation between age and DAVF in men. Borden II and III (p = 0.038) and aggressive symptoms (p = 0.023) were related to DM. CONCLUSION: There was a positive relation between DM and DAVF in a Korean population. DAVFs with aggressive symptoms and behaviour were more commonly related to DM.

Investigation of d-Amino Acid-Based Surfactants and Nanocomposites with Gold and Silica Nanoparticles as against Multidrug-Resistant Bacteria Agents.

d-amino acid-based surfactants (d-AASs) were synthesized and their antimicrobial activity was evaluated. N-α-lauroyl-d-arginine ethyl ester hydrochloride (d-LAE), d-proline dodecyl ester (d-PD), and d-alanine dodecyl ester (d-AD) were found to have antibacterial activity against both Gram-positive and -negative bacteria, but less efficacy against Gram-negative bacteria. For these reasons, combining antimicrobial agents with nanoparticles is a promising technique for improving their antibacterial properties to eliminate drug-resistant pathogens. d-LAE coated on gold (AuNP) and silica (SiNP) nanoparticles has more efficient antibacterial activity than that of d-LAE alone. However, unlike d-LAE, d-PD has enhanced antibacterial activity upon being coated on AuNP. The antibacterial d-AASs and their nanocomposites with nanoparticles were synthesized in an environmentally friendly manner and are expected to be valuable new antimicrobial agents against multidrug-resistant (MDR) pathogens.

Polymer-ultrathin graphite sheet-polymer composite structured flexible nonvolatile bistable organic memory devices.

We present data, which were obtained before bending and after bending, for the electrical bistabilities, memory stabilities, and memory mechanisms of three-layer structured flexible bistable organic memory (BOM) devices, which were fabricated utilizing the ultrathin graphite sheets (UGS) sandwiched between insulating poly(methylmethacrylate) (PMMA) polymer layers. The UGS were formed by transferring UGS (about 30 layers) and using a simple spin-coating technique. Transmission electron microscopy (TEM) measurements were performed to investigate the microstructural properties of the PMMA/UGS/PMMA films. Current-voltage (I-V) measurements were carried out to investigate the electrical properties of the BOM devices containing the UGS embedded in the PMMA polymer. Current-time (I-t) and current-cycle measurements under flat and bent conditions were performed to investigate the memory stabilities of the BOM devices. The memory characteristics of the BOM maintained similar device efficiencies after bending and were stable during repeated bendings of the BOM devices. The mechanisms for these characteristics of the fabricated BOM are described on the basis of the I-V results.

Flexible organic bistable devices based on graphene embedded in an insulating poly(methyl methacrylate) polymer layer.

The electrical properties of flexible nonvolatile organic bistable devices (OBDs) fabricated with graphene sandwiched between two insulating poly(methyl methacrylate) (PMMA) polymer layers were investigated. Current-voltage (I-V) measurements on the Al/PMMA/graphene/PMMA/indium-tin-oxide/poly(ethylene terephthalate) devices at 300 K showed a current bistability due to the existence of the graphene, indicative of charge storage in the graphene. The maximum ON/OFF ratio of the current bistability for the fabricated OBDs was as large as 1 x 10(7), and the endurance number of ON/OFF switchings was 1.5 x 10(5) cycles, and an ON/OFF ratio of 4.4 x 10(6) was maintained for retention times larger than 1 x 10(5) s. No interference effect was observed for the scaled-down OBDs containing a graphene layer. The memory characteristics of the OBDs maintained similar device efficiencies after bending and were stable during repetitive bendings of the OBDs. The mechanisms for these characteristics of the fabricated OBDs are described on the basis of the I-V results.

Enantioselective Thiolysis and Aminolysis of Cyclic Anhydrides Using a Chiral Diamine-Derived Thiourea Catalyst.

Catalytic desymmetrization of cyclic anhydrides has been widely investigated in the field of organocatalysis. Using this approach, many stereocenters can be established in a single, symmetry-breaking transformation. Herein, a thiourea organocatalyst was prepared in a single step from a chiral diamine, (R,R)-1,2-diphenylethylenediamine, and used for the desymmetrization of various cyclic anhydrides through double hydrogen-bonding activation. The asymmetric ring-opening reaction of the cyclic anhydride proceeded via the enantioselective addition reaction catalyzed by diamine thiourea. Thiolysis afforded the desired products in the yields of 86-98% and enantioselectivities of 60-94%, while aminolysis afforded the yields of 90-94% and enantioselectivities of 90-95%.

Enantioselective organocatalytic Michael reactions using chiral (R,R)-1,2-diphenylethylenediamine-derived thioureas.

Although the Michael addition is a very well-known and widely applied reaction, cost-effective, metal-free, and readily prepared organic catalysts remain rare. A chiral, bifunctional, (R,R)-1,2-diphenylethylenediamine-derived thiourea organic catalyst was developed and applied to asymmetric Michael additions of nitroalkenes under neutral conditions. Generally, fluorine-substituted thiourea catalysts exhibited high chemical yields and enantioselectivities under neutral conditions. The mild reactions were tolerant of many functional groups and afforded good-to-excellent yields, as well as high diastereo- and enantioselectivities for the Michael adducts. The utility of the transformation was demonstrated by the synthesis of a bioactive compound, (R)-Phenibut.

Three-Dimensional Angiographic Evaluation of Middle Cerebral Artery Trunk Aneurysms: Demonstration of the Close Relationship Between the Early Frontal Cortical Branches and Lateral Lenticulostriate Arteries.

BACKGROUND: For the treatment planning of a patient with a middle cerebral artery (MCA) trunk aneurysm, understanding the anatomic relationship among the aneurysm, branching vessels, and lenticulostriate arteries (LSAs) is important. We aimed to demonstrate the branching-vessel anatomy related to an MCA trunk aneurysm using 3-dimensional (3D) angiography. METHODS: We retrospectively reviewed 3D angiographic findings of 64 cases of MCA trunk aneurysms using a 3D workstation with various postprocessing conditions. We classified the aneurysms into 4 groups (early frontal cortical branch [EFCB], early temporal cortical branch [ETCB], LSA, and nonbranching aneurysms) and analyzed the relationship between the branching vessels and the LSAs. RESULTS: There were 30 EFCB aneurysms, 25 ETCB aneurysms, 7 LSA aneurysms, and 2 nonbranching aneurysms. Twenty-six (86.7%) of the 30 EFCB aneurysms shared common origins and were associated with the LSAs, but none of the 25 ETCB aneurysms were. Three of 24 patients who received clipping for an EFCB aneurysm experienced a postoperative infarction in the LSA territory. In these 3 patients, the LSA originated from the EFCB and was closely related with the aneurysm. CONCLUSIONS: We have identified a clinically important anatomic relationship between the MCA trunk aneurysm and branching vessels, including the LSAs. EFCB aneurysms show a close relationship with the LSAs. Pretreatment identification of the origin of the LSAs is important to obviate any perforator injury in EFCB aneurysms.

Feasibility of the Transradial or the Transbrachial Approach in Various Neurointerventional Procedures.

PURPOSE: The generally preferred vascular access for neurointerventional procedures is the transfemoral approach (TFA). In complicated cases such as patients with aortic diseases or tortuous vessels, transradial or transbrachial approaches (TRA or TBA) could be good alternatives. The purpose of this study is to review a single medical center experience using the alternative accesses. MATERIALS AND METHODS: We reviewed the medical records of 30 TRA and 10 TBA cases among 2,073 cases treated between January 2010 and July 2013. We reviewed and analyzed the frequency of TRA and TBA, the reason the operator had chosen the TRA or TBA, the category of the procedure, caliber of the sheath, the success rate, and the complications rates. RESULTS: The most common reason the non-TFA route was chosen was due to the patient's tortuous vascular system (n=24, 60%). The most common category of intervention was balloon angioplasty and/or stent placement (n=18, 45%). The largest caliber of the introducing sheath was 6 Fr in TRA and 7 Fr in TBA. Procedural success was achieved in 37 cases (success rate: 92.5%), and in three cases it failed. Six patients with complications were reported. Among them, four cases of minor complications (10%) occurred. There was no serious complication directly related to the access problem. CONCLUSION: Both TRA and TBA can be good alternative access routes when TFA is not appropriate in various neurointervential procedures.

Mechanical Thrombectomy Using the Solitaire FR system for Occlusion of the Top of the Basilar Artery: Intentional Detachment of the Device after Partial Retrieval.

Acute, distal, basilar artery occlusion is a challenging neurovascular emergency. There have been several reports regarding the successful application of the Solitaire FR device for treating this lesion. However, due to the lack of a suitable, balloon-tipped, guiding catheter for the vertebral artery, during this procedure we frequently experience the occurrence of clot fragmentation and distal migration. There may be some technical solutions to solve this problem. The purpose of this report is to present a technical variation of using the Solitaire FR, and which is referred to as the 'intentional device detachment technique.' As a clot tends to re-embolize during its passage through the tortuous cranio-cervical junction level of the vertebral artery or its passage through the tip of the guiding catheter, due to the lack of proximal flow arrest, we thought that not removing the stent segment of the device which is capturing the clot could avoid this problem. We were able to successfully apply this technique in two cases. We believe that this technique can be a possible technical option for using the Solitaire FR device when a patient has little concern regarding the subsequent use of antiplatelets.

Two microcatheter technique for embolization of arteriovenous fistula with liquid embolic agent.

Problem with embolization of arteriovenous fistula (AVF) with liquid embolic agent is its over-penetration into the veins or regurgitation to the proximal feeder without reaching the shunt point. We present a technique that controls the flow of AVF during embolization. Two microcatheter technique consists of positioning one microcatheter close to the AVF for embolization, and with another microcatheter at the proximal feeding artery to control the AVF flow by coiling. Selective angiograms obtained using a distally positioned microcatheter before and after coiling, were compared how much stagnant effect was achieved. Using two microcatheter technique, AVF occlusion was achieved with good penetration of glue to the venous side of the AVF. Its advantage is the ability to push glue into the shunt without causing over-penetration of glue or its reflux along the feeder. Two microcatheter technique was safe and effective in glue embolization of AVF and also expected to be applied with other liquid embolic agent like Onyx.

Current status of neurointerventional activities in Korea.

Neurointervention which deals with neurovascular disease in brain, head-and-neck and spines are one of the rapidly evolving medical fields. Several indices representing neurointerventional activities are still increasing year-by-year in Korea. We review current trend in major neurovascular diseases requiring usage of specific medical devices and some issues related to administrative process of the government approval.

Segmental difference of the hepatic fibrosis from chronic viral hepatitis due to hepatitis B versus C virus infection: comparison using dual contrast material-enhanced MRI.

OBJECTIVE: We wanted to identify the geographic differences in hepatic fibrosis and their associations with the atrophy-hypertrophy complex in patients with chronic viral hepatitis using the dual-contrast material-enhanced MRI (DC-MRI) with gadopentetate dimeglumine and ferucarbotran. MATERIALS AND METHODS: Patients with chronic C (n = 22) and B-viral hepatitis (n = 35) were enrolled for determining the subjective grade of fibrosis (the extent and thickness of fibrotic reticulations) in the right lobe (RL), the caudate lobe (CL), the medial segment (MS) and the lateral segment (LS) of the liver, with using a 5-grade scale, on the gradient echo T2(*)-weighted images of DC-MRI. The fibrosis grades of different segments were compared using the Kruskal-Wallis test followed by post-hoc analysis to establish the segment-by-segment differences. The incidences of two pre-established morphologic signs of cirrhosis were also compared with each other between the two groups of patients. RESULTS: There were significant intersegmental differences in fibrosis grades of the C-viral group (p = 0.005), and the CL showed lower fibrosis grades as compared with the grades of the RL and MS, whereas all lobes were similarly affected in the B-viral group (p = 0.221). The presence of a right posterior hepatic notch was significantly higher in the patients with intersegmental differences of fibrosis between the RL and the CL (19 out of 25, 76%) than those without such differences (6 out of 32, 19%) (p < 0.001). An expanded gallbladder fossa showed no significant relationship (p = 0.327) with the segmental difference of the fibrosis grades between the LS and the MS. CONCLUSION: The relative lack of fibrosis in the CL with more advanced fibrosis in the RL can be a distinguishing feature to differentiate chronic C-viral hepatitis from chronic B-viral hepatitis and this is closely related to the presence of a right posterior hepatic notch.

Characteristics of spontaneous contraction in the circular smooth muscles of cat ileum.

We investigated the characteristics of spontaneous contraction in feline ileal circular smooth. Smooth muscle contractions were recorded by an isometric force transducer. The neurotoxin tetrodotoxin did not alter the spontaneous contraction of the circular muscles. Atropine or guanethidine also did not affect on the contraction. In Ca2+-free Krebs, the spontaneous contraction completely disappeared in the muscles. An L-type Ca2+ channel blockade with nimodipine decreased the amplitude of spontaneous contraction. A selective inhibitor of the sarcoplasmic reticulum Ca2+-ATPase, thapsigargin, had not no effect on spontaneous contraction within incubation time for 10 min. However, phosphoinositide-specific phospholipase C inhibitor, U-73122, decreased the frequency of the contraction in circular smooth muscle These results suggest that the neuronal component, adrenergic or cholinergic innervation was not involved in spontaneous activity and that extracellular Ca2+ influx via an L-type Ca2+ channel may mediate the contractile amplitude in circular smooth muscles of cat ileum.

MLCK and PKC Involvements via Gi and Rho A Protein in Contraction by the Electrical Field Stimulation in Feline Esophageal Smooth Muscle.

We have shown that myosin light chain kinase (MLCK) was required for the off-contraction in response to the electrical field stimulation (EFS) of feline esophageal smooth muscle. In this study, we investigated whether protein kinase C (PKC) may require the on-contraction in response to EFS using feline esophageal smooth muscle. The contractions were recorded using an isometric force transducer. On-contraction occurred in the presence of N(G)-nitro-L-arginine methyl ester (L-NAME), suggesting that nitric oxide acts as an inhibitory mediator in smooth muscle. The excitatory composition of both contractions was cholinergic dependent which was blocked by tetrodotoxin or atropine. The on-contraction was abolished in Ca(2+)-free buffer but reappeared in normal Ca(2+)-containing buffer indicating that the contraction was Ca(2+) dependent. 4-aminopyridine (4-AP), voltage-dependent K(+) channel blocker, significantly enhanced on-contraction. Aluminum fluoride (a G-protein activator) increased on-contraction. Pertussis toxin (a G(i) inactivator) and C3 exoenzyme (a rhoA inactivator) significantly decreased on-contraction suggesting that Gi or rhoA protein may be related with Ca(2+) and K(+) channel. ML-9, a MLCK inhibitor, significantly inhibited on-contraction, and chelerythrine (PKC inhibitor) affected on the contraction. These results suggest that endogenous cholinergic contractions activated directly by low-frequency EFS may be mediated by Ca(2+), and G proteins, such as Gi and rhoA, which resulted in the activation of MLCK, and PKC to produce the contraction in feline distal esophageal smooth muscle.

Comparing the pre- and post-impact ball and racquet kinematics of elite tennis players' first and second serves: a preliminary study.

The aim of this study was to compare the pre- and post-impact three-dimensional kinematics of the ball and racquet during first and second serves performed by elite tennis players. Data were collected from four male and four female right-handed professional players during competition using two high-speed cameras (200 Hz). For each player, one first serve and one second serve from the 'deuce' or right service court that landed within the specified target area were analysed. To test for significant differences between the first and second serves, Wilcoxon tests (P < or = 0.05) were performed on selected parameters. The results indicate that the ball travelled forward and to the left during the flight phase of the toss in all but one trial. The average pre-impact ball forward location for the first serve was significantly more in front and had a higher associated forward ball velocity than the corresponding values for the second serve. On average, the decrease in post-impact ball speed from the first to the second serve was 24.1%. No significant differences between the first and second serves were found in the pre-impact racquet head speed and orientation, which was represented as a unit vector perpendicular to the racquet face. The major adjustments made by the players when going from the first to second serve were a decrease in pre-impact ball forward location (P < or = 0.01) and an increase in the pre-impact racquet vertical and lateral velocities (both P < or = 0.05). This implies that the players tossed the ball closer to the body and imparted topspin and sidespin on the ball by changing the racquet vertical and lateral velocities when going from the first to the second serve.