Association between pill burden and interdialytic weight gain in patients with hemodialysis: A multi-center cross-sectional study

High daily pill burden affects quality of life and mortality. High interdialytic weight gain (IDWG) is associated with increased mortality. We examined the association between pill burden and IDWG in hemodialysis patients. This cross-sectional study was conducted in six dialysis centers in Japan in June 2017. The exposure was the number of daily tablets, and outcome was defined as 1 day of relative IDWG divided by post-dialysis weight from the previous session. Among 188 outpatients (mean age, 68.7 [SD, 10.3] years; men, 67.0%; median dialysis vintage, 76.0 [interquartile range, 36.5, 131.5] months), the mean number of daily tablets was 19.7 ± 9.9, and mean relative weight gain was 3.5 ± 1.2%. Multiple linear regression analysis showed a regression coefficient of 0.021 (95% confidence interval: 0.004-0.039), indicating that one additional tablet prescription increased the IDWG by 0.021%. In hemodialysis patients, the daily pill burden was a significant, independent risk for increased relative IDWG.

Nintedanib-induced glomerular microangiopathy: a case report

Nintedanib, a triple tyrosine kinase inhibitor of vascular endothelial growth factor receptor, platelet-derived growth factor receptor, and fibroblast growth factor receptor, has been used in idiopathic pulmonary fibrosis and adenocarcinoma in advanced non-small cell lung cancer. Although vascular endothelial growth factor inhibitors have been reported to cause endothelial injury and glomerular microangiopathy, nintedanib-induced glomerular microangiopathy has not been reported. A 68-year-old man with a history of primary aldosteronism, idiopathic pulmonary fibrosis, and pleomorphic carcinoma of the lung developed proteinuria and leg edema after nintedanib initiation. Kidney biopsy revealed prominent endothelial and mesangial injury. Proteinuria improved after nintedanib withdrawal. To the best of our knowledge, this is the second case report of nintedanib-induced glomerular microangiopathy. Although the incidence of nephropathy among patients receiving nintedanib is unknown at this moment, we recommend monitoring urinary protein excretion and blood pressure in patients receiving nintedanib and performing kidney biopsy to determine any histopathological change.

A Functional Parathyroid Cyst from the Hemorrhagic Degeneration of a Parathyroid Adenoma

A 77-year-old man with a history of hypertension, prostate hyperplasia, and urolithiasis was admitted for acute kidney injury caused by hypercalcemia. Neck ultrasonography showed a large cyst adjacent to the right lower thyroid lobe. Although a ^99mtechnetium sestamibi scan was negative, an extremely high intracystic intact parathyroid hormone level suggested that the cyst had a parathyroid origin and that a functional parathyroid cyst was present. Immunohistochemical staining for the calcium-sensing receptor (CaSR) after right lower parathyroidectomy revealed CaSR-positive cells lining the cyst, indicating that the functional parathyroid cyst had originated from the hemorrhagic degeneration of a parathyroid adenoma.

Proton-pump Inhibitor-induced Severe Hypomagnesemia and Hypocalcemia are Clinically Masked by Thiazide Diuretic

Hypomagnesemia, a side effect of proton-pump inhibitors (PPIs), can be asymptomatic. The presence of hypocalcemia or hypokalemia is indicative of hypomagnesemia; however, the concomitant use of PPIs and thiazide may mask hypocalcemia. A 79-year-old woman with a history of chronic heart failure and chronic kidney disease developed symptomatic hypocalcemia and hypomagnesemia. Five weeks earlier, she had developed thiazide-induced hyponatremia, so thiazide had been discontinued. Reviewing the patient's charts revealed that three discontinued thiazide administrations in the clinical course had unmasked hypocalcemia. Our case demonstrates that thiazide-induced hypercalcemia can be so prominent as to mask PPI-induced hypocalcemia and hypomagnesemia.

Kidney autotransplantation for the treatment of renal artery occlusion after endovascular aortic repair: a case report

BACKGROUND

Unintentional renal artery occlusion after endovascular aneurysm repair (EVAR) for abdominal aortic aneurysm remains one of the most unfavorable complications. Renal salvage options include percutaneous transluminal renal artery angioplasty (PTRA) and open hepatosplenorenal bypass. However, the usefulness of kidney autotransplantation (AutoTx) remains unclear.

CASE PRESENTATION

A 76-year-old woman with a right solitary kidney attributable to a left renal thromboembolism had previously undergone EVAR with a stent graft for an infrarenal aortic aneurysm, which led to ostial occlusion of the right renal artery. In addition, she had undergone PTRA and stenting. Two days before admission, she developed leg edema and hypertension, leading her to visit the hospital. Her serum creatinine level was 2.4 (baseline, 1.0) mg/dL. Acute kidney injury due to renal artery in-stent restenosis was suspected; re-angioplasty was attempted on day 2 of hospitalization, but was unsuccessful. Her renal function did not improve and anuria persisted; thus, hemodialysis was initiated on the same day. The right kidney size (8.6 cm) was preserved relative to her body size, with only mild cortical atrophy. Doppler ultrasonography and mercaptoacetyltriglycine scintigraphy revealed minimal but significant perfusion of the right kidney. Therefore, we considered that kidney perfusion was sustained and renal function could be reversed. On day 25 of hospitalization, right kidney AutoTx to the right iliac fossa was performed to reestablish adequate renal perfusion and reverse the need for dialysis. Soon after the procedure, the patient started passing urine. Her renal function improved; her serum creatinine level decreased to 1.0 mg/dL on day 33 of hospitalization. Hemodialysis was discontinued after the surgery. Zero-hour kidney biopsy showed only mild tubular injury, with neither tubular necrosis nor glomerular abnormalities.

CONCLUSIONS

Kidney AutoTx can be performed for patients with renal artery in-stent occlusion after unsuccessful PTRA who previously underwent EVAR. Our case showed successful recovery of renal function nearly 1 month after renal artery occlusion, indicating that revascularization should be considered even if it is delayed, as the kidney might be perfused through collateral circulation.

Binding of 131I-Labeled Tissue-Type Plasminogen Activator on De-Endothelialized Lesions in Rabbits

Tissue-type plasminogen activator (t-PA) which has a high affinity for fibrin in the clot, was labeled with 131I by the iodogen method, and its binding to de-endothelialized lesions in the rabbit was measured to assess the detectability of thrombi. The de-endothelialized lesion was induced in the abdominal aorta with a Fogarty 4F balloon catheter. Two hours after the de-endothelialization, 131I-labeled t-PA (125 ± 46 μCi) was injected intravenously. The initial half-life of the agent in blood (n = 12) was 2.9 ± 0.4 min. The degree of binding of 131I-labeled t-PA to the de-endothelialized lesion was evaluated at 15 min (n = 6) or at 30 min (n = 6) after injection of the agent. In spite of the retention of the biochemical properties of 131I-labeled t-PA and the presence of fibrin deposition at the de-endothelialized lesion, the binding of t-PA to the lesion was not sufficiently strong. Lesion-to-control ratios (cpm/g/cpm/g) were 1.65 ± 0.40 (at 15 min) and 1.39 ± 1.31 (at 30 min), and lesion-to-blood ratios were 1.39 ± 0.32 (at 15 min) and 1.36 ± 0.23 (at 30 min). These results suggest that radiolabeled t-PA may be inappropriate as a radiopharmaceutical for the scintigraphic detection of a pre-existing thrombotic lesion.

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.

Denosumab for treatment of immobilization-related hypercalcemia in a patient with end-stage renal disease

The efficacy and safety of denosumab for the treatment of immobilization-related hypercalcemia in end-stage renal disease remain uncertain. We describe the case of a hemodialysis patient with immobilization-related hypercalcemia who was successfully treated with denosumab. A 79-year-old man admitted for hemodialysis after sustaining an acute kidney injury developed immobilization-related hypercalcemia due to the impairment resulting from an acute myocardial infarction, acute heart failure, and catheter-related bloodstream infection. After admission, the patient's corrected serum calcium rose to 12.9 from 8.8 mg/dL. A bisphosphonate (alendronate) was administered, but it was ineffective. Subsequently, treatment with denosumab proved to be effective and his corrected serum calcium level declined to 9.3 mg/dL within 1 week. Hypocalcemia, which is an adverse effect of denosumab, was prevented using active vitamin D and calcium supplementation, and his calcium level stabilized. Thus, our case demonstrates that denosumab is a viable therapeutic option for dialysis patients experiencing immobilization-related hypercalcemia.

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 β-defensin 2 was markedly up-regulated. These findings indicate that these molecules in oral epithelial cells are functional receptors that induce antibacterial responses.

Detection and characterisation of sub-critical nuclei during reactive Pd metal nucleation by X-ray absorption spectroscopy

The interfacial reduction of aqueous [PdCl₄]²⁻ at the interface with an organic solution of ferrocene has been characterised by X-ray absorption fine structure (XAFS) spectroscopy.

Effects of short duration stretching on disuse muscle atrophy in immobilized rat soleus muscles

The purpose of this study was to determine whether short duration stretching is ameliorating for disuse muscle atrophy in immobilized rat soleus muscles. Eighteen male Wistar rats (age, 8 weeks; weight, 311.0 ± 35.6 g) were divided randomly into control (n=3) and experimental (n=15) groups. Bilateral ankles of each rat in the experimental group were fixed in full planter flexion with a plaster cast. After the experimental groups rats were immobilized for 4 weeks, animals were divided into three groups: immobilization alone (group I, n=3), stretch training for 30 min/day for 1 or 3 weeks after remobilization (group S, n=6), and spontaneous recovery (non stretch training) for 1 or 3 weeks after remobilization (group NS, n=6). At the end of the experimental periods, the soleus muscle was extracted from hindlimb, and the frozen sections were stained with myofibrillar adenosine triphosphatase. After 1 week of remobilization, the means of the muscle fiber diameters for type I fibers in group S had increased significantly compared with group NS, but those for type II fibers in group S did not significantly differ from that for group NS. After 3 weeks of remobilization, the means of the muscle fiber diameters for types I and II fibers in group S had increased significantly compared with group NS. No difference in the fiber type distribution were observed between the experimental group. Our findings suggest that short duration stretching induces recovery from disuse muscle atrophy after joint fixation.

[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 β-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 β-defensin 2 in human oral epithelial cells via NF-κB. 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.

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.

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.

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.

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.

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.

Priming of human oral epithelial cells by interferon-gamma to secrete cytokines in response to lipopolysaccharides, lipoteichoic acids and peptidoglycans

An earlier study reported that human gingival epithelial cells in primary culture and oral epithelial cell lines KB and HSC-2 cells were devoid of membrane CD14 (mCD14) and did not show enhanced production of interleukin (IL)-8 or granulocyte macrophage-colony stimulating factor (GM-CSF) upon stimulation with bacterial cell-surface components such as lipopolysaccharide (LPS), lipoteichoic acid (LTA), peptidoglycan (PGN) and synthetic muramyldipeptide (MDP) even in the presence of serum. The present study demonstrated that after treatment with interferon (IFN)-gamma for 3 days, these cells secreted IL-8 and GM-CSF in response to the bacterial components. Treatment with IFN-gamma enhanced Toll-like receptor (TLR) 2, TLR4, MD-2 and MyD88 mRNA expression as determined by reverse transcriptase PCR. Anti-TLR2 and anti-TLR4 monoclonal antibodies (MAbs) inhibited the IL-8 production induced by PGN and LTA as well as LPS, respectively, in IFN-gamma-primed oral epithelial cells, whereas neither MAb inhibited IL-8 production induced by MDP. These findings suggested that IFN-gamma primed oral epithelial cells to produce cytokines upon stimulation with various bacterial components by up-regulation of the TLR system.

Store-operated Ca2+ entry uncoupled with ryanodine receptor and junctional membrane complex in heart muscle cells

Store-operated Ca2+ entry (SOCE) is the Ca2+ influx that is activated on depletion of intracellular Ca2+ stores. Although SOCE is found in a variety of cell types, its activation mechanism and molecular identity remain to be clarified. Current experimental results suggest that SOCE channels are activated by direct coupling with Ca2+ release channels on depleted stores. Here we report SOCE in cardiac myocytes, that was prominently sensitive to Zn2+ but resistant to inhibitors for voltage-dependent Ca2+ channels and Na+/Ca2+ exchangers. The SOCE activity may be developmentally regulated, because the SOCE was easily detected during embryonic and neonatal stages but not in mature myocytes from adult hearts. In cardiac myocytes, ryanodine receptor type 2 (RyR-2) is thought to be the sole Ca2+ release channel on the intracellular store, and junctophilin type 2 (JP-2) contributes to formation of the junctional complex between the cell surface and store membranes. Using the knockout mice, we also examined possible involvement of the Ca2+ release channel and junctional membrane complex in cardiac SOCE. Apparently normal SOCE activities were retained in mutant myocytes lacking RyR-2 or JP-2, suggesting that neither the Ca2+ release channel nor junctional membrane complex is involved in activation of cardiac SOCE.

Activation of human gingival epithelial cells by cell-surface components of black-pigmented bacteria: augmentation of production of interleukin-8, granulocyte colony-stimulating factor and granulocyte-macrophage colony-stimulating factor and expression of intercellular adhesion molecule 1

Black-pigmented anaerobic bacteria, such as Porphyromonas gingivalis and Prevotella intermedia, are amongst the predominant bacteria in periodontal pockets and have been implicated in periodontal diseases. To elucidate the roles of gingival keratinocytes, which are the first cells encountered by oral bacteria in periodontal diseases, human gingival keratinocytes in primary culture were stimulated with cell-surface components of P gingivalis and Pr. intermedia. A glycoprotein fraction from Pr. intermedia (PGP) clearly augmented the release of interleukin-8, granulocyte colony-stimulating factor and granulocyte-macrophage colony-stimulating factor, as determined by enzyme-linked immunosorbent assay. This PGP also induced expression of intercellular adhesion molecule-1 (ICAM-1), as determined by flow cytometry. The augmentation of mRNA expression for these molecules was also confirmed by reverse transcription PCR. In contrast, lipopolysaccharide (LPS) from Pr. intermedia and Escherichia coli was completely inactive in these assays. LPS fraction and purified fimbriae from P gingivalis exhibited weak activities. Cytokine production and ICAM-1 expression by gingival keratinocytes might cause accumulation and activation of neutrophils in the epithelium and, therefore, may be involved in the initiation and development of inflammation in periodontal tissues.

Neutrophil proteinase 3-mediated induction of bioactive IL-18 secretion by human oral epithelial cells

IL-18, a potent IFN-gamma-inducing cytokine, is expressed by various nonimmune cells as well as macrophages, suggesting that it has important physiological and immunological roles. The present study focused on the mechanism of active IL-18 induction from human oral epithelial cells. The epithelial cells and the cell lines constitutively express IL-18 mRNA and the 24-kDa precursor form of IL-18. Bioactive IL-18 exhibiting IFN-gamma-inducing activity was detected in the supernatant of the cells on costimulation with neutrophil proteinase 3 (PR3) and LPS for 24 h after IFN-gamma-priming for 3 days. An active 18-kDa form of IL-18 was detected in lysate and supernatant of the cells only after the above treatment and the induction was inhibited by cycloheximide and by serine proteinase inhibitors. After the treatment, lactate dehydrogenase activity was not detected in the cell culture supernatant, and PR3 was detected only in the membrane and not in cytoplasm fractions of the cells. Caspase-1 was not detected in the cells even after the treatment and the IL-18 induction was not inhibited by a caspase-1 inhibitor. These results suggest that the PR3-mediated induction of bioactive IL-18 secretion from oral epithelial cells in combination with LPS after IFN-gamma-priming occurred via a caspase-1-independent pathway, and provide new insight into the possible involvement of a neutrophil proteinase in the induction of bioactive IL-18 in oral inflammation such as periodontitis.

Contrasting responses of human gingival and colonic epithelial cells to lipopolysaccharides, lipoteichoic acids and peptidoglycans in the presence of soluble CD14

Gingival epithelial cells may form the first barriers of defense against oral bacteria in periodontal tissues. We stimulated human gingival epithelial cells (keratinocytes) in primary culture, the oral epithelial cell line KB and the colonic epithelial cell line SW620 with various bacterial cell-surface components in the presence or absence of soluble CD14 (sCD14). The SW620 produced interlukin-8 (IL-8) in an sCD14-dependent manner in response to lipopolysaccharide, lipoteichoic acid and peptidoglycan. However, the primary gingival epithelial cells and KB cells did not show enhanced production of IL-8 upon stimulation with these components even in the presence of serum. These human epithelial cells were devoid of membrane CD14, as determined by flow cytometry, and CD14 mRNA expression, as determined by reverse transcriptase-PCR. In contrast, gingival epithelial cells and KB cells expressed the mRNA expression for Toll-like receptor (TLR) 2, TLR4, MD2 and MyD88 to the similar extent to those observed in SW620 cells.

Structural domains influencing sensitivity to isothiourea derivative inhibitor KB-R7943 in cardiac Nna(+)/Ca(2+) exchanger

KB-R7943 (2-[2-[4-(4-nitrobenzyloxy)phenyl]ethyl]isothiourea methanesulfonate) is a potent and selective Na(+)/Ca(2+) exchange (NCX) inhibitor that is 3-fold more inhibitory to NCX3 than to NCX1 or NCX2. Here we searched for amino acid residues that may form the KB-R7943 receptor in the exchanger by analyzing the function of chimeras between NCX1 and NCX3 as well as of their site-directed mutants. We found that the highly conserved alpha-2 repeat of the exchanger is almost exclusively responsible for the difference in drug response of the isoforms. Such difference was mostly reproduced by single substitutions of residues in the alpha-2 repeat (V820G or Q826V in NCX1 and A809V or A809I in NCX3), suggesting their importance in drug sensitivity. Cysteine scanning mutagenesis of the alpha-2 repeat of NCX1 identified one residue (Gly833) that caused a large (> or = 30-fold) reduction in drug sensitivity. We found that the Gly-to-Thr substitution caused even larger reduction in drug sensitivity. Interestingly, extracellularly applied KB-R7943 at 0.8 microM markedly inhibited the whole-cell outward exchange current, whereas the drug applied intracellularly at 30 microM did not. These results suggest that KB-R7943 inhibits the exchanger from the external side in intact cells and that a region of the alpha-2 repeat of NCX1 containing Gly833 may participate in the formation of the drug receptor. Because we suggested previously that Gly833 is accessible from the inside of a cell, the results raised an interesting possibility that this residue may alter its position during Na(+)/Ca(2+) exchange in such a way that it becomes accessible to external drug.

The Na+/Ca2+ exchanger NCX1 has oppositely oriented reentrant loop domains that contain conserved aspartic acids whose mutation alters its apparent Ca2+ affinity

We examined the membrane topology and functional importance of residues in regions of the Na(+)/Ca(2+) exchanger NCX1 encompassing the conserved internal alpha repeats by substituted cysteine scanning analysis and kinetic analysis of site-directed mutants. The results suggest that both the alpha-1 repeat and a region encompassing the alpha-2 repeat and its immediately C-terminal segment contain reentrant loop domains, each oriented in an opposite direction with respect to the membrane. We found that single or multiple mutations of six residues including Asn-125 and conserved aspartates Asp-130, Asp-825, and Asp-829 in the alpha repeat reentrant domains reduce the apparent affinity of the exchanger for extracellular Ca(2+) by up to 6-fold. In contrast, the triple cysteine mutation D130C/D825C/D829C did not influence the current-voltage (I-V) relationship of the exchange current. Cysteine accessibility scanning with different thiol modifiers suggested that N125C, D130C, and D825C may be located in a restricted aqueous space in the membrane accessible only to ions when examined with external probes, although N125C and D825C were previously shown to be internally accessible during exchange reaction. The results suggest that these reentrant domains in the alpha repeats may participate in the formation of the ion transport pathway in the exchanger with some of the aspartates possibly lining it or located close to it.

Peak systolic blood pressure in exercise testing is associated with scintigraphic severity of myocardial ischemia in patients with exercise-induced ST-segment depression

Some electrocardiographic variables, including the degree of maximal ST-segment depression (STD), may not necessarily indicate the severity of exercise-induced myocardial ischemia. The present study examined whether maximal STD correlates with the severity and extent of exercise-induced myocardial ischemia, as assessed by thallium-201 (201Tl) imaging, and which parameter of exercise testing reflects scintigraphic severity and extent in 270 patients who had a 1 mm or greater horizontal or down-sloping STD on exercise 201Tl imaging. The scintigraphic severity and extent of exercise-induced ischemia was assessed and correlated with maximal STD, number of positive leads, workload, peak heart rate, peak systolic blood pressure (SBP), rate-pressure product, chest pain and the Duke treadmill score. Most of the scintigraphic markers of the severity and extent of ischemia had significant but weak correlation with all of those parameters. Multivariate analysis demonstrated that peak SBP and the Duke treadmill score (chest pain in only simple variables model) correlated independently with scintigraphic severity and extent of ischemia. Furthermore, most of the patients with a peak SBP of 200 mmHg or more had milder and less extensive ischemia. In patients with exercise-induced STD, the scintigraphic severity and extent of ischemia may be estimated by peak SBP and the Duke treadmill score.

Physiological functions of the regulatory domains of the cardiac Na(+)/Ca(2+) exchanger NCX1

Physiological functions of the intracellular regulatory domains of the Na(+)/Ca(2+) exchanger NCX1 were studied by examining Ca(2+) handling in CCL39 cells expressing a low-affinity Ca(2+) regulatory site mutant (D447V/D498I), an exchanger inhibitory peptide (XIP) region mutant displaying no Na(+) inactivation (XIP-4YW), or a mutant lacking most of the central cytoplasmic loop (Delta246-672). We found that D447V/D498I was unable to efficiently extrude Ca(2+) from the cytoplasm, particularly during a small rise in intracellular Ca(2+) concentration induced by the physiological agonist alpha-thrombin or thapsigargin. The same mutant took up Ca(2+) much less efficiently than the wild-type NCX1 in Na(+)-free medium when transfectants were not loaded with Na(+), although it appeared to take up Ca(2+) normally in transfectants preloaded with Na(+). XIP-4YW and, to a lesser extent, Delta246-672, but not NCX1 and D447V/D498I, markedly accelerated the loss of viability of Na(+)-loaded transfectants. Furthermore, XIP-4YW was not activated by phorbol ester, whereas XIP-4YW and D447V/D498I were resistant to inhibition by ATP depletion. The results suggest that these regulatory domains play important roles in the physiological and pathological Ca(2+) handling by NCX1, as well as in the regulation of NCX1 by protein kinase C or ATP depletion.

A case of acute myocardial infarction associated with topical use of minoxidil (RiUP) for treatment of baldness

A 45-year-old Japanese man with paroxysmal atrial fibrillation (AF) developed acute anteroseptal myocardial infarction (MI). He had used 1% topical minoxidil (RiUP) once a day for 4 months before the onset of MI for treatment of baldness. Coronary angiography demonstrated severe stenosis at the proximal portion of the left anterior descending coronary artery with a tilling defect. Electrocardiographic monitoring revealed paroxysmal AF and sinus bradycardia with sinus arrests, suggestive of sick sinus syndrome. Topical minoxidil is now widely used for the treatment of male pattern baldness. Although it may be difficult to relate topical use of minoxidil to myocardial ischemia, a greater awareness of its toxicity will be necessary, and patients with cardiovascular disorders should be excluded from the therapy.

Exercise myocardial perfusion scintigraphy is useful for evaluating myocardial ischemia even in the elderly

Pharmacologic stress testing is recommended to elderly patients as a valuable alternative to exercise testing. We examined whether exercise testing is as useful for evaluating myocardial ischemia in the elderly as in the young. The consecutive 1,508 patients who underwent exercise 201Tl single-photon emission computed tomography (SPECT) were divided into six age groups: 6-29 years (n = 56), 30-44 (n = 143), 45-54 (n = 311), 55-64 (n = 498), 65-74 (n = 402), and 75-88 (n = 98). Both heart rate and rate-pressure product at peak exercise were significantly lower in patients aged 75-88 than in the other five groups. The frequency of ischemic ST depression was higher in patients aged 75-88 than in those aged 6-74, although the difference was not significant. Moreover, the frequency of 201Tl transient defect was significantly higher in patients aged 75-88 than in those aged 6-74. On the other hand, the sensitivity of ischemic ST depression for 201Tl transient defect was similar among the six groups, but the specificity was significantly lower in patients aged 75-88 than in those aged 6-74. In conclusion, exercise 201Tl SPECT is useful for evaluating myocardial ischemia even in the elderly, but exercise electrocardiography has limitations such as lower specificity in the elderly than 201Tl SPECT.

Multivessel coronary thrombosis, acute myocardial infarction, and no reflow in a patient with essential thrombocythaemia

Essential thrombocythaemia (ET) has been reported rarely to cause coronary thrombosis, but the management is still undefined. A 63 year old woman with multivessel coronary thrombosis, acute myocardial infarction (MI), and no reflow in reperfused coronary artery in association with ET is presented. The patient's platelet count was only moderately raised at the onset of MI, but peripheral blood smear and bone marrow evaluation revealed clumping giant platelets and numerous large hyperploid megakaryocytes. Long term prophylaxis with antiplatelet agents in patients with ET is recommended, even if the platelet count is not largely raised. Cytoreductive treatment may also be effective for secondary prevention when thrombotic complications occur.

Cardiac autonomic neuropathy in patients with chronic renal failure on hemodialysis

To characterize uremic cardiac autonomic neuropathy, we measured plasma catecholamines, analyzed the 24-hour heart rate variability (HRV), and acquired serial images with (123)I-metaiodobenzylguanidine (MIBG) in 44 patients with chronic renal failure on hemodialysis and in 14 controls. Time-domain measures were calculated using the Marquette HRV program. MIBG clearance rates from the heart and lung were evaluated on planar images, and the regional MIBG uptake in the left ventricular myocardium was evaluated with single-photon emission computed tomography. Compared with controls, plasma dopamine and norepinephrine levels were elevated (p < 0.001 and p = 0.03, respectively), and all the time-domain measures of HRV were reduced in the patients (p < 0.001). The MIBG clearance rate from the heart was higher (p < 0.001), that from the lung was lower (p < 0.001), and the myocardial MIBG distribution was more heterogeneous in patients than in controls (total uptake score p </= 0.03). These variables were similar between 26 patients without and 18 patients with hypertension. Uremic cardiac autonomic neuropathy may be characterized by high plasma levels of dopamine and norepinephrine, reduced HRV, and abnormal MIBG kinetics in the heart with heterogeneous myocardial MIBG distribution, suggesting cardiac sympathetic overactivity and parasympathetic deterioration. In addition, abnormal MIBG kinetics in the lung may imply pulmonary sympathetic nervous dysfunction and/or endothelial dysfunction in uremic patients.

Syncope caused by nonsteroidal anti-inflammatory drugs and angiotensin-converting enzyme inhibitors

A 85-year-old woman with diabetes mellitus and prior myocardial infarction was transferred to the emergency room with loss of consciousness due to marked bradycardia caused by hyperkalemia. The T wave during right ventricular pacing was tall and tent-shaped while the concentration of serum potassium was high, and its amplitude during pacing was decreased after correction of the serum potassium level. Simultaneously with the correction, normal sinus rhythm was restored. The cause of hyperkalemia was considered to be several doses of loxoprofen, a nonsteroidal anti-inflammatory drug (NSAID), prescribed for her lumbago by an orthopedic specialist, in addition to the long-term intake of imidapril, an angiotensin-converting enzyme inhibitor (ACEI), prescribed for her hypertension by a cardiologist. This case warns physicians that the combination of NSAID and ACEI can produce serious side effects in aged patients who frequently suffer from hypertension, diabetes mellitus, ischemic heart disease, and degenerative joint disease.

Increased cytosolic Ca(2+) concentration in endothelial cells by calmodulin antagonists

Many functions of endothelial cells are Ca(2+)/calmodulin dependent, whereas the role of calmodulin in the regulation of cytosolic Ca(2+) ([Ca(2+)](i)) remains largely unexplained. In the present study, effects of various calmodulin antagonists on [Ca(2+)](i) were investigated in cultured aortic endothelial cells loaded with the Ca(2+)-sensitive dye fura-2/AM, and were compared with those of calmodulin-dependent protein kinase II (CaM kinase II) inhibitors. The calmodulin antagonists W-7, calmidazolium and fendiline provoked dose-dependent increases in [Ca(2+)](i). However, the CaM kinase II inhibitors KN-93 and lavendustin C had no effect on [Ca(2+)](i). In the absence of extracellular Ca(2+), pretreatment of cells with bradykinin (BK) and thapsigargin completely prevented W-7-stimulated increase in [Ca(2+)](i). Alternatively, pretreatment with W-7 also completely blocked BK- and thapsigargin-stimulated increases in [Ca(2+)](i). The time course of the Ca(2+)-response in W-7 treated cells was identical to that in thapsigargin-treated cells, but not that in BK-stimulated cells, suggesting that calmodulin antagonists could share a common signaling pathway with thapsigargin to increase [Ca(2+)](i) in endothelial cells. These findings indicate that calmodulin is involved in the regulation of [Ca(2+)](i), and may play an important role in the uptake of Ca(2+) to intracellular stores.