The significance of bromide in the Brust-Schiffrin synthesis of thiol protected gold nanoparticles.

The mechanism of the two-phase Brust-Schiffrin synthesis of alkane thiol protected metal nanoparticles is known to be highly sensitive to the precursor species and reactant conditions. In this work X-ray absorption spectroscopy is used in conjunction with liquid/liquid electrochemistry to highlight the significance of Br- in the reaction mechanism. The species [AuBr4]- is shown to be a preferable precursor in the Brust-Schiffrin method as it is more resistant to the formation of Au(i) thiolate species than [AuCl4]-. Previous literature has demonstrated that avoidance of the Au(i) thiolate is critical to achieving a good yield of nanoparticles, as [Au(i)X2]- species are more readily reduced by NaBH4. We propose that the observed behavior of [AuBr4]- species described herein explains the discrepancies in reported behavior present in the literature to date. This new mechanistic understanding should enable nanoparticle synthesis with a higher yield and reduce particle size polydispersity.

[Exposure for harvesting gastroepiploic artery graft].

We present out technique for harvesting the gastroepiploic artery (GEA). We use a Universal Stabilizer Arm and an assistant attachment to push the liver against the diaphragm, giving en enough working space to harvest the graft. Between January and December 2007, 99 isolated coronary artery bypass grafting (CABG)s were performed, and in 36 (36.4%) patients the GEA was harvested using this technique. The mean operation time was 251.1 +/- 40.5 minutes and the mean number of distal anastomosis was 3.6 +/- 0.8. The early patency rate of the GEA graft was 95%. Combined use of a Universal Stabilizer Arm and an assistant attachment provide good exposure for harvesting the GEA.

[Delayed surgery for traumatic rupture of the aortic arch with an isolated left vertebral artery; report of a case].

Although traumatic rupture of the thoracic aorta has been considered a surgical emergency, we report here an example of successful delayed surgery for acute traumatic rupture of the aortic arch with an isolated left vertebral artery in an 18-year-old woman. The patient was.admitted to the intensive care unit with hemothorax and, rib fractures, and a decision was made to treat the aortic injury conservatively until the patient was stabilized. She underwent surgery after 3 months of observation. After the isolated left vertebral artery had been anastomosed to the left carotid artery, total arch replacement was performed. Delayed surgery for aortic rupture as a treatment choice may be of benefit in selected cases of complex trauma.

[Assessment of proximal aortic anastomosis device in coronary artery bypass grafting].

The aim of this study was to assess the feasibility and safety of a new proximal anastomotic device (PAD) "Enclose II" in coronary artery bypass grafting (CABG). PAD enables the construction of a proximal aortic anastomosis without the use of partial clamp of the ascending aorta, thus reduces the incidence of adverse perioperative neurologic injury related to atheroembolic events. This device was used in 41 off-pump CABG and 11 on-pump beating heart CABG patients for performing 46 radial artery (RA) and 9 vein anastomoses to the aorta. The subjects were 43 males and 9 females, with a mean age of 63.6 years. Thirteen (25%) patients had severe atherosclerotic cerebrovascular lesions preoperatively. The mean flow in the RA graft was 52.4 +/- 26.9 ml/min and that of saphenous vein graft (SVG) was 61.1 +/- 31.9 ml/min. Angiography showed all grafts patent. There was no procedure-related adverse events or cerebrovascular complication. Enclose II device can be a valuable tool to perform RA and vein anastomoses in CABG.

Synergism between TLRs and NOD1/2 in oral epithelial cells.

Oral epithelium is the first barrier against oral bacteria in periodontal tissue. Oral epithelial cells constitutively express Toll-like receptors (TLRs) and NOD1/2, functional receptors which induce the production of antibacterial factors such as peptidoglycan recognition proteins (PGRPs) and beta-defensin 2, but not pro-inflammatory cytokines such as interleukin (IL)-8. In this study, we hypothesized that innate immune responses in the oral epithelium are enhanced in inflamed tissue. We found that NOD1 and NOD2 agonists, in combination with TLR agonists, synergistically induced production of PGRPs and of beta-defensin 2 in human oral epithelial cells via NF-kappaB. In contrast, co-stimulation with NOD1/2 and TLR ligands had no effect on the production of pro-inflammatory cytokines (IL-6, IL-8, and monocyte chemoattractant protein-1). These findings indicate that, in innate immune responses to invading microbes, a combination of signaling through TLRs and NODs leads to the synergistic activation of antibacterial responses in the oral epithelium.

Gingipains from Porphyromonas gingivalis synergistically induce the production of proinflammatory cytokines through protease-activated receptors with Toll-like receptor and NOD1/2 ligands in human monocytic cells.

Gingipains (HRgpA, RgpB and Kgp) are cysteine proteinases and virulence factors of Porphyromonas gingivalis, the major causative bacterium of periodontal disease. To study synergistic effects of gingipains and signalling via Toll-like receptors (TLRs) and NOD1/2, we investigated effects of a gingipain on the secretion of proinflammatory cytokines from monocytic THP-1 cells in the presence of pathogen-associated molecular patterns (PAMPs). Gingipains stimulated interleukin (IL)-8's secretion from THP-1 cells, which was completely inhibited by proteinase inhibitors of gingipain and increased in the presence of PAMPs. Synergistic effects of gingipains and PAMPs were also seen in the secretion of IL-6 and MCP-1 and reduced to about 50% the secretion of IL-8 from THP-1 cells treated with siRNA targeting either protease-activated receptor (PAR)-1, -2 or -3. PAR agonist peptides mimicked the synergistic effects of gingipains with PAMPs. These results indicate that gingipains stimulate the secretion of cytokines from monocytic cells through the activation of PARs with synergistic effects by PAMPs. This is the first report of synergism of signalling via PARs, and TLRs or NOD1/2. The host defence system against P. gingivalis may be triggered through the activation of PARs by gingipains and augmented by PAMPs from this pathogen via TLRs or NOD1/2.

[On-pump beating coronary artery bypass grafting with axillary cannulation in the presence of atherosclerotic lesions in the ascending aorta].

A 72-year-old man was admitted to our hospital for dyspnea and chest pain. Coronary artery bypass grafting (CABG) was scheduled because of severe stenosis of the left main trunk. Computed tomography showed severe atherosclerotic lesions in the whole aorta, especially in the ascending aorta. Although off-pump CABG was thought to be the 1st choice, we determined that it would be difficult to establish a cardiac support device due to atherosclerotic lesions in case of sudden deterioration. We performed on-pump beating CABG with axillary cannulation with an 8 mm tube graft. Postoperatively, we recognized no symptoms of stroke, and the patient was discharged on the 12th postoperative day. Axillary cannulation using a side graft was useful in the presence of atherosclerotic lesions in the ascending aorta.

In vitro development of gut-like tissue demonstrating rhythmic contractions from embryonic mouse intestinal cells.

The rhythmic motility of the intestine is regulated by the interstitial cells of Cajal (ICC) and the enteric nervous system. Rhythmic motility is considered to occur after the differentiation of mesenchymal progenitor cells into ICC during the late embryonic period. In this study, we successfully reconstructed a gut-like tissue demonstrating rhythmic contractions by culturing dispersed cells enzymatically isolated from the mouse intestine during the mid-embryonic period. These intestinal cells were reconstituted into a collagen gel at high density, made to proliferate considerably, and grew into a gut-like tissue after 1 week of culturing. The reconstituted tissue showed rhythmic contractions and stained positive for the specific marker proteins of neurones and ICC, PGP9.5 and c-Kit. The tissue also demonstrated network formation by developing nerve cells and ICC. Moreover, in the presence of nifedipine, c-Kit-immunopositive cells showed spontaneous Ca(2+) oscillation, which is considered to be coupled to the electrical activity that corresponds to slow waves. Therefore, this culture system may be of use in elucidating the developmental mechanisms of gastrointestinal motility.

Functional TLRs and NODs in human gingival fibroblasts.

Since human gingival fibroblasts are the major cells in periodontal tissues, we hypothesized that gingival fibroblasts are endowed with receptors for bacterial components, which induce innate immune responses against invading bacteria. We found clear mRNA expression of Toll-like receptors (TLR)1, TLR2, TLR3, TLR4, TLR5, TLR6, TLR7, TLR8, TLR9, MD-2, MyD88, NOD1, and NOD2 in gingival fibroblasts. Gingival fibroblasts constitutively expressed these molecules. Upon stimulation with chemically synthesized ligands mimicking microbial products for these receptors, the production of pro-inflammatory cytokines, such as interleukin (IL)-6, IL-8, and monocyte chemoattractant protein-1, was markedly up-regulated. Furthermore, the production of pro-inflammatory cytokines induced by TLR and NOD ligands was significantly inhibited by an RNA interference assay targeted to NF-kappaB. These findings indicate that these innate immunity-related molecules in gingival fibroblasts are functional receptors involved in inflammatory reactions in periodontal tissues, which might be responsible for periodontal pathogenesis.

Laboratory investigation of microelectronics-based stimulators for large-scale suprachoroidal transretinal stimulation (STS).

This paper describes the technological developments underlying the realization of a reliable and reproducible microchip-based stimulator with a large number of stimulus electrodes. A microchip-based stimulator with over 500 electrodes for suprachoroidal transretinal stimulation (STS) is proposed in this paper, and an example is presented. To enhance reliability and reproducibility for such a large array, we introduce a flip-chip bonding technique and place microchips on the reverse side of a substrate. A square microchip of size 600 microm was fabricated using 0.35 microm standard CMOS process technology. Twelve microchips were flip-chip bonded on a polyimide substrate through Au bumps. To evaluate the feasibility of the proposed device, we successfully fabricated a stimulator with 12 microchips and 118 electrodes made of Pt/Au bumps, and demonstrated their operation in a saline solution for 2 weeks. Also, to evaluate the device operation in vivo, a stimulator with one active IrO(x) electrode was implanted into the scleral pocket of a rabbit and electrical evoked potential (EEP) signals with a threshold of 100 microA were obtained. We also fabricated a simulator with 64 microchips that has 576 electrodes (9 electrodes in a microchip times 64 microchips).

Enhancement of TLR-mediated innate immune responses by peptidoglycans through NOD signaling.

Toll-like receptors (TLRs) recognize common motifs, pathogen-associated molecular patterns (PAMPs), in microorganisms. Bacterial PAMPs are mainly distributed on cell-surfaces. Peptidoglycans (PGNs) are ubiquitous constituents of bacterial cell walls. Muramyldipeptide (MDP; N-acetylmuramyl-l-alanyl-d-isoglutamine) is a common and key structure of PGNs and exhibits most the of bioactivities of PGNs. Recently, the intracellular receptor for MDP was revealed to be NOD2. Another bioactive moiety of PGNs, diaminopimelic acid (DAP) containing desmuramylpeptides (DMPs), senses another intracellular receptor, NOD1. MDP-primed mice exhibited hyper-responses to endotoxin and other bacterial components, which sense Toll-like receptors (TLRs), although MDP itself does not exhibit apparent activity in mice. On the other hand, DMPs exhibited definite activity in mice, and the most powerful DMP, FK565, exhibited stronger priming activity than MDP. In human monocytic cells, both MDP and DMPs exhibited definite activities; marked synergistic interleukin (IL)-8 secretion was induced by DMPs and MDP in combination with synthetic TLR agonists, and suppression of the mRNA expressions of NOD1 and NOD2, respectively, by RNA interference specifically inhibited synergistic IL-8 secretion. In human dendritic cells (DCs), synergistic T helper type 1 responses are induced by combined stimulations of synthetic NOD and TLR agonists. Considering these findings altogether, in host-bacteria interactions, host cells should recognize bacteria via both TLRs and NODs, which might induce synergistic innate and adaptive immune responses.

Abdominal aortic aneurysm in a patient presenting with ischemic colitis.

A 76-year-old man with an abdominal aortic aneurysm (AAA) initially presented with ischemic colitis, which was improved by conservative treatment. Preoperative assessment by computerized axial tomography scanning and aortography revealed an infrarenal type AAA with mural thrombus, stenoses of the right common iliac artery and the left internal iliac artery. The patient underwent aortoiliac bypass surgery with resection of the stenoses, and reconstruction of the left internal iliac artery. No complications including bowel ischemia, were noted postoperatively. This case emphasized the potential benefits of the extraperitoneal approach to the aorta, reconstruction of both internal iliac arteries, and use of prostaglandin E1.

Toll-like receptors, NOD1, and NOD2 in oral epithelial cells.

Oral epithelium might be the first barrier against oral bacteria in periodontal tissue. We hypothesized that oral epithelium is endowed with innate immune receptors for bacterial components, which play roles in host defense against bacterial infection without being accompanied by excessive inflammatory responses. We found clear expression of Toll-like receptor (TLR)4 as well as TLR2, and strong expression of NOD1 and NOD2 in normal oral epithelial tissues by immunohistochemical analysis. We also showed that primary oral epithelial cells in culture expressed these molecules using PCR, flow cytometry, and immunostaining. In inflamed oral epithelium, cell-surface localizations of TLR2 and TLR4 were more clearly observed than in healthy tissue. Upon stimulation with synthetic ligands for these receptors, the expression of beta-defensin 2 was markedly up-regulated. These findings indicate that these molecules in oral epithelial cells are functional receptors that induce antibacterial responses.

AURKA is one of the downstream targets of MAPK1/ERK2 in pancreatic cancer.

DUSP6/MKP-3, a specific inhibitor of MAPK1/ERK2, frequently loses its expression in primary pancreatic cancer tissues. This evidence suggests that constitutive activation of MAPK1 synergistically induced by frequent mutation of KRAS2 and the loss of function of DUSP6 plays key roles in pancreatic carcinogenesis and progression. By profiling of gene expressions associated with downregulation of MAPK1 induced by exogenous overexpression of DUSP6 in pancreatic cancer cells, we found that AURKA/STK15, the gene encoding Aurora-A kinase, which plays key roles in cellular mitosis, was among the downregulated genes along with its related genes, which included AURKB, TPX2 and CENPA. An association of expression and promoter activity of AURKA with MAPK activity was verified. Knockdown of ETS2 resulted in a reduction of AURKA expression. These results indicate that AURKA is a direct target of the MAPK pathway and that its overexpression in pancreatic cancer is induced by hyperactivation of the pathway, at least via ETS2.

Unusual remnant thymic tissue in an adult mimicking malignant neoplasm: escape from age-related involution.

Here we report on a 55-year-old man with an abnormal anterior mediastinal shadow and multiple nodules in the thymus, which increased in size over a period of 15 months. He was diagnosed with early prostatic cancer, and treated with chemotherapy. Although no definite preoperative diagnosis was obtained, surgery was performed because of the possibility of malignant neoplasm or metastasis. Extended thymectomy was performed and pathological examination revealed that the nodules were remnant thymic tissue and not malignant lesions. Although the cause of this unusual remnant thymic tissue remains unclear, it may have been related to autoimmune or endocrinological disease.

A multi-chip-architecture based flexible stimulation device for retinal prosthesis with a flip-chip packaging technique.

In the present work, we designed a multi-chip-architecture based flexible neural stimulation device for retinal prosthesis. Based on the multi-chip architecture, a novel CMOS stimulation device was successfully designed and characterized. A packaging technique for thin, flexible neural stimulation device was also proposed and demonstrated. Flip-chip bonding technology plays an essential role in the fabrication of the present thin and flexible neural stimulation device.

Post-challenge hyperinsulinaemia rather than hyperglycaemia is associated with the severity of coronary artery disease in patients without a previous diagnosis of diabetes mellitus.

OBJECTIVE: To ascertain the prevalence of abnormal glucose metabolism in patients with coronary artery disease (CAD) but no previous diagnosis of diabetes mellitus (DM) and to examine the relation between the severity of CAD and responses of glucose and insulin to the glucose tolerance test. METHODS AND RESULTS: Abnormalities of glucose metabolism and insulin response were analysed in 144 patients with CAD without a previous diagnosis of DM who underwent both coronary arteriography and 75 g oral glucose tolerance test. The proportions of impaired and diabetic glucose tolerance were very high (39% for impaired and 21% for diabetic glucose tolerance); only 40% had normal glucose tolerance. The parameters of glucose metabolism were not associated with the number of diseased coronary arteries or the presence of previous myocardial infarction (MI). However, the insulin concentration at 60 minutes or 120 minutes after glucose challenge, insulin area, and the ratio of insulin to glucose area were significantly higher in patients with significant coronary stenosis and with previous MI. Fasting glucose concentration and most conventional risk factors did not predict post-challenge hyperinsulinaemia. CONCLUSION: Patients with CAD without a previous diagnosis of DM had a high prevalence of abnormal glucose tolerance. Post-challenge hyperinsulinaemia was associated with the number of diseased coronary arteries and the presence of previous MI. The insulin response to the glucose challenge test requires further investigation as a potential risk factor for CAD and a potential target for intervention.

Chemically synthesized pathogen-associated molecular patterns increase the expression of peptidoglycan recognition proteins via toll-like receptors, NOD1 and NOD2 in human oral epithelial cells.

Peptidoglycan recognition proteins (PGRPs), a novel family of pattern recognition molecules (PRMs) in innate immunity conserved from insects to mammals, recognize bacterial cell wall peptidoglycan (PGN) and are suggested to act as anti-bacterial factors. In humans, four kinds of PGRPs (PGRP-L, -Ialpha, -Ibeta and -S) have been cloned and all four human PGRPs bind PGN. In this study, we examined the possible regulation of the expression of PGRPs in oral epithelial cells upon stimulation with chemically synthesized pathogen-associated molecular patterns (PAMPs) in bacterial cell surface components: Escherichia coli-type tryacyl lipopeptide (Pam3CSSNA), E. coli-type lipid A (LA-15-PP), diaminopimelic acid containing desmuramyl peptide (gamma-D-glutamyl-meso-DAP; iE-DAP), and muramyldipeptide (MDP). These synthetic PAMPs markedly upregulated the mRNA expression of the four PGRPs and cell surface expression of PGRP-Ialpha and -Ibeta, but did not induce either mRNA expression or secretion of inflammatory cytokines, in oral epithelial cells. Suppression of the expression of Toll-like receptor (TLR)2, TLR4, nucleotide-binding oligomerization domain (NOD)1 and NOD2 by RNA interference specifically inhibited the upregulation of PGRP mRNA expression induced by Pam3CSSNA, LA-15-PP, iE-DAP and MDP respectively. These PAMPs definitely activated nuclear factor (NF)-kappaB in the epithelial cells, and suppression of NF-kappaB activation clearly prevented the induction of PGRP mRNA expression induced by these PAMPs in the cells. These findings suggested that bacterial PAMPs induced the expression of PGRPs, but not proinflammatory cytokines, in oral epithelial cells, and the PGRPs might be involved in host defence against bacterial invasion without accompanying inflammatory responses.

Muramyldipeptide and diaminopimelic acid-containing desmuramylpeptides in combination with chemically synthesized Toll-like receptor agonists synergistically induced production of interleukin-8 in a NOD2- and NOD1-dependent manner, respectively, in human monocytic cells in culture.

Two types of synthetic peptidoglycan fragments, diaminopimelic acid (DAP)-containing desmuramylpeptides (DMP) and muramyldipeptide (MDP), induced secretion of interleukin (IL)-8 in a dose-dependent manner in human monocytic THP-1 cells, although high concentrations of compounds are required as compared with chemically synthesized Toll-like receptor (TLR) agonists mimicking bacterial components: TLR2 agonistic lipopeptide (Pam3CSSNA), TLR4 agonistic lipid A (LA-15-PP) and TLR9 agonistic bacterial CpG DNA. We found marked synergistic IL-8 secretion induced by MDP or DAP-containing DMP in combination with synthetic TLR agonists in THP-1 cells. Suppression of the mRNA expression of nucleotide-binding oligomerization domain (NOD)1 and NOD2 by RNA interference specifically inhibited the synergistic IL-8 secretion induced by DMP and MDP with these TLR agonists respectively. In accordance with the above results, enhanced IL-8 mRNA expression and the activation of nuclear factor (NF)-kappaB induced by MDP or DMP in combination with synthetic TLR agonists were markedly suppressed in NOD2- and NOD1-silenced cells respectively. These findings indicated that NOD2 and NOD1 are specifically responsible for the synergistic effects of MDP and DMP with TLR agonists, and suggested that in host innate immune responses to invading bacteria, combinatory dual signalling through extracellular TLRs and intracellular NODs might lead to the synergistic activation of host cells.