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1.
Annu Int Conf IEEE Eng Med Biol Soc ; 2018: 4685-4688, 2018 Jul.
Article in English | MEDLINE | ID: mdl-30441395

ABSTRACT

This paper reports successful measurement of even-related potential (ERP) using candle-like dry microneedle electrodes, which can acquire high-quality electroencephalogram (EEG) from hairy parts without any pretreatment. In our previous work, we successfully measured spontaneous EEG activity and its application to assess the stress state of the subjects. ERPs originate from electrophysiological response to stimulus and are one of the most important indices to capture the cognitive and sensory activities. In this work, using the candle-like dry microelectrodes, we demonstrate successful measurement of ERPs elicited by oddball tasks. Two oddball tasks using pure tone stimuli and speech stimuli were assigned to the subjects, where EEG was acquired from the parietal region (Cz in international 10-20 system). Note that no pretreatment, such as removal of hairs and abrasion of the scalp, was applied. As a result, P300 and mismatch negativity (MMN) were successfully measured in the both oddball tasks from the averaged EEG after the stimuli. Based on these results and given the attractive natures of the candle-like dry microneedle electrodes; they do not need any skin treatment and conductive gels and they can measure EEG from the hairy parts, the developed electrodes will accelerate cognitive neuroscience research using ERPs.


Subject(s)
Electroencephalography , Evoked Potentials , Acoustic Stimulation , Electrodes , Hair , Microelectrodes , Scalp
2.
J Dent Res ; 95(1): 102-9, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26442946

ABSTRACT

The interfacial interaction of veneering ceramic with zirconia is still not fully understood. This study aimed to characterize morphologically and chemically the zirconia-veneering ceramic interface. Three zirconia-veneering conditions were investigated: 1) zirconia-veneering ceramic fired on sandblasted zirconia, 2) zirconia-veneering ceramic on as-sintered zirconia, and 3) alumina-veneering ceramic (lower coefficient of thermal expansion [CTE]) on as-sintered zirconia. Polished cross-sectioned ceramic-veneered zirconia specimens were examined using field emission gun scanning electron microscopy (Feg-SEM). In addition, argon-ion thinned zirconia-veneering ceramic interface cross sections were examined using scanning transmission electron microscopy (STEM)-energy dispersive X-ray spectrometry (EDS) at high resolution. Finally, the zirconia-veneering ceramic interface was quantitatively analyzed for tetragonal-to-monoclinic phase transformation and residual stress using micro-Raman spectroscopy (µRaman). Feg-SEM revealed tight interfaces for all 3 veneering conditions. High-resolution transmission electron microscopy (HRTEM) disclosed an approximately 1.0-µm transformed zone at sandblasted zirconia, in which distinct zirconia grains were no longer observable. Straight grain boundaries and angular grain corners were detected up to the interface of zirconia- and alumina-veneering ceramic with as-sintered zirconia. EDS mapping disclosed within the zirconia-veneering ceramic a few nanometers thick calcium/aluminum-rich layer, touching the as-sintered zirconia base, with an equally thick silicon-rich/aluminum-poor layer on top. µRaman revealed t-ZrO2-to-m-ZrO2 phase transformation and residual compressive stress at the sandblasted zirconia surface. The difference in CTE between zirconia- and the alumina-veneering ceramic resulted in residual tensile stress within the zirconia immediately adjacent to its interface with the veneering ceramic. The rather minor chemical elemental shifts recorded in the veneering ceramic did not suffice to draw definitive conclusions regarding potential chemical interaction of the veneering ceramic with zirconia. Sandblasting damaged the zirconia surface and induced phase transformation that also resulted in residual compressive stress. Difference in CTE of zirconia versus that of the veneering ceramic resulted in an unfavorable residual tensile stress at the zirconia-veneering ceramic interface.


Subject(s)
Ceramics/chemistry , Dental Materials/chemistry , Dental Veneers , Yttrium/chemistry , Zirconium/chemistry , Aluminum/chemistry , Aluminum Oxide/chemistry , Argon/chemistry , Calcium/chemistry , Dental Etching/methods , Dental Polishing/methods , Hot Temperature , Humans , Materials Testing , Microscopy, Electron, Scanning , Microscopy, Electron, Transmission , Nanoparticles/chemistry , Silicon/chemistry , Spectrometry, X-Ray Emission , Spectrum Analysis, Raman , Stress, Mechanical , Surface Properties , Thermodynamics
3.
Placenta ; 36(6): 693-8, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25801460

ABSTRACT

INTRODUCTION: Hypotaurine is a precursor of taurine and an antioxidant, and is concentrated in fetal plasma compared to maternal plasma. Hypotaurine is significantly decreased in fetal plasma of ezrin (Vil2) knock-out mice, and fetuses show intrauterine growth retardation. The aim of this study was to characterize the mechanism through which cellular hypotaurine level is maintained in placental trophoblasts, and the effect of hypotaurine on oxidative stress induced by hydrogen peroxide (H2O2). METHODS: Hypotaurine transfer from extracellular fluid and antioxidant effect of hypotaurine were analyzed in rat placental trophoblast TR-TBT 18d-1 cells. RESULTS: We found that hypotaurine is concentrated into rat placental trophoblast TR-TBT 18d-1 cells, and the level of hypotaurine was markedly reduced by culture in medium supplemented with dialyzed fetal bovine serum (FBS) instead of normal FBS. The hypotaurine level recovered almost completely when hypotaurine was added to the culture medium, indicating that intracellular hypotaurine is predominantly supplied by transport across the plasma membrane from extracellular fluid rather than by biosynthesis. Hypotaurine showed a cytoprotective effect against H2O2-induced oxidative damage in TR-TBT 18d-1 cells. Hypotaurine treatment of TR-TBT 18d-1 cells increased antioxidant capacity against hydroxyl radical and peroxyl radical. The concentration of intracellular hydroxyl radical induced by H2O2 in TR-TBT 18d-1 cells was significantly reduced by hypotaurine treatment. DISCUSSION: These results indicate that intracellular hypotaurine is mainly supplied to placental trophoblasts by transfer from extracellular fluid across the plasma membrane, and may play a role in cell protection by scavenging reactive oxygen species.


Subject(s)
Oxidative Stress/drug effects , Placenta/drug effects , Taurine/analogs & derivatives , Trophoblasts/drug effects , Animals , Female , Hydrogen Peroxide/pharmacology , Mice, Knockout , Placenta/metabolism , Placenta/pathology , Pregnancy , Rats , Reactive Oxygen Species/metabolism , Taurine/pharmacology , Trophoblasts/metabolism , Trophoblasts/pathology
4.
Br J Cancer ; 112(2): 345-51, 2015 Jan 20.
Article in English | MEDLINE | ID: mdl-25422910

ABSTRACT

BACKGROUND: FOXA1 expression is a good prognostic marker for endocrine therapy in hormone-positive breast cancer. We retrospectively examined breast cancer patients with luminal human epidermal growth factor receptor 2 (HER2)-negative tumours, as defined by immunohistochemistry, who received neo-adjuvant chemotherapy (NAC) and investigated the relationship between treatment effects and FOXA1 expression. METHODS: Biopsy specimens from 103 luminal HER2-negative tumours were immunohistochemically examined. FOXA1 effects on chemo-sensitivity were also investigated employing in vitro experiments. RESULTS: FOXA1 and Ki67 expressions independently predicted a pathological complete response (pCR). Knockdown of FOXA1 by siRNA boosted the chemo-effect in oestrogen receptor-positive cells. The Cox hazards model revealed a pCR to be the strongest factor predicting a good patient outcome. CONCLUSIONS: Our present study showed low FOXA1 expression to be associated with a good response to NAC in luminal HER2-negative breast cancer. Improved outcomes of these patients suggest that NAC should be recommended to patients with low FOXA1 tumours.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Breast Neoplasms/metabolism , Carcinoma, Ductal, Breast/metabolism , Gene Expression , Hepatocyte Nuclear Factor 3-alpha/metabolism , Adult , Aged , Breast Neoplasms/drug therapy , Breast Neoplasms/mortality , Bridged-Ring Compounds/administration & dosage , Carcinoma, Ductal, Breast/drug therapy , Carcinoma, Ductal, Breast/mortality , Cell Line, Tumor , Chemotherapy, Adjuvant , Cyclophosphamide/administration & dosage , Disease-Free Survival , Docetaxel , Epirubicin/administration & dosage , Female , Fluorouracil/administration & dosage , Gene Knockdown Techniques , Hepatocyte Nuclear Factor 3-alpha/genetics , Humans , Kaplan-Meier Estimate , Ki-67 Antigen/metabolism , Middle Aged , Neoadjuvant Therapy , Proportional Hazards Models , Receptor, ErbB-2/metabolism , Receptors, Progesterone/metabolism , Retrospective Studies , Taxoids/administration & dosage , Treatment Outcome , Young Adult
5.
J Physiol Pharmacol ; 64(1): 65-75, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23568973

ABSTRACT

We examined the effect of egualen, a stable azulene derivative, against gastric damage induced by ischemia/reperfusion (I/R), gastric bleeding induced by double antiplatelet therapy with aspirin (ASA) plus clopidogrel, and small intestinal damage generated by loxoprofen, and investigated the possible mechanisms involved in its protective action. Male C57BL/6 mice or SD rats were used under urethane anesthesia (gastric lesions) or in a conscious (intestinal lesions) state. I/R-induced gastric injury was produced in mice by clamping the celiac artery for 30 min, followed by reperfusion for 60 min. Gastric bleeding was induced in rats by luminal perfusion with 25 mM ASA+50 mM HCl for 2 hours in the presence of clopidogrel (30 mg/kg). To produce small intestinal lesions the rats were given loxoprofen (60 mg/kg) p.o. and killed 24 hours later. Egualen was given i.d. 60 min before I/R or ASA perfusion, while given p.o. twice 30 min before and 6 hours after loxoprofen. Egualen significantly prevented the I/R-induced gastric damage, and the effect was equivalent to that of seratrodast (TXA2 antagonist). This agent also significantly suppressed gastric bleeding induced by ASA plus clopidogrel, similar to PGE2. Likewise, egualen significantly prevented loxoprofen-induced damage in the small intestine, accompanied by an increase in the secretion of mucus and suppression of bacterial invasion as well as iNOS expression. These results suggest that egualen has a prophylactic effect against various lesions in the gastrointestinal mucosa, probably through its characteristic pharmacological properties, such as TXA2 antagonistic action, local mucosal protection, and stimulation of mucus secretion.


Subject(s)
Azulenes/pharmacology , Gastrointestinal Hemorrhage/drug therapy , Gastrointestinal Tract/blood supply , Phenylpropionates/toxicity , Reperfusion Injury/drug therapy , Sesquiterpenes/pharmacology , Animals , Aspirin/toxicity , Benzoquinones/toxicity , Clopidogrel , Gastric Mucosa/blood supply , Gastric Mucosa/drug effects , Gastric Mucosa/metabolism , Gastric Mucosa/pathology , Gastrointestinal Hemorrhage/chemically induced , Gastrointestinal Hemorrhage/metabolism , Gastrointestinal Hemorrhage/pathology , Gastrointestinal Tract/drug effects , Gastrointestinal Tract/pathology , Heptanoic Acids/toxicity , Male , Mice , Mice, Inbred C57BL , Mucus/metabolism , Nitric Oxide Synthase Type II/metabolism , Peptic Ulcer/prevention & control , Peroxidase/metabolism , Platelet Aggregation Inhibitors/toxicity , Rats , Rats, Sprague-Dawley , Reperfusion Injury/pathology , Ticlopidine/analogs & derivatives , Ticlopidine/toxicity
6.
Rev Sci Instrum ; 83(2): 02A346, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22380193

ABSTRACT

We have developed an electron cyclotron resonance ion source apparatus, which is designed for the production of endohedral fullerene. In this study, we irradiated the Fe(+) beam to the C(60) thin film. We changed the experimental condition of the dose and the ion energy. We could observe the Fe + C(60) peak by analysis of the time-of-flight mass spectrometry. The highest intensity of the Fe + C(60) peak was observed at the ion energy of 200 eV. The Fe + C(60) peak intensity tended to become high in the case of long irradiation time and large dose.


Subject(s)
Electrons , Fullerenes/chemistry , Iron/chemistry , Radiation Dosage
7.
Nat Mater ; 11(4): 323-8, 2012 Feb 19.
Article in English | MEDLINE | ID: mdl-22344326

ABSTRACT

High-T(c) cuprates, iron pnictides, organic BEDT and TMTSF, alkali-doped C(60), and heavy-fermion systems have superconducting states adjacent to competing states exhibiting static antiferromagnetic or spin density wave order. This feature has promoted pictures for their superconducting pairing mediated by spin fluctuations. Sr(2)RuO(4) is another unconventional superconductor which almost certainly has a p-wave pairing. The absence of known signatures of static magnetism in the Sr-rich side of the (Ca, Sr) substitution space, however, has led to a prevailing view that the superconducting state in Sr(2)RuO(4) emerges from a surrounding Fermi-liquid metallic state. Using muon spin relaxation and magnetic susceptibility measurements, we demonstrate here that (Sr,Ca)(2)RuO(4) has a ground state with static magnetic order over nearly the entire range of (Ca, Sr) substitution, with spin-glass behaviour in Sr(1.5)Ca(0.5)RuO(4) and Ca(1.5)Sr(0.5)RuO(4). The resulting new magnetic phase diagram establishes the proximity of superconductivity in Sr(2)RuO(4) to competing static magnetic order.

8.
Acupunct Electrother Res ; 36(3-4): 221-30, 2011.
Article in English | MEDLINE | ID: mdl-22443025

ABSTRACT

Using Bi-Digital O-Ring Test electromagnetic field resonance phenomenon between 2 identical substances, it is possible to draw on the surface of the human body several points similar to the acupuncture points of Traditional Chinese Medicine-TCM with the help of histological slides of 12 organs of the main TCM Meridians, using the method first described by Yoshiaki Omura Sc.D. M.D. To determine the relationship of the Lung Meridian of TCM and the points drawn with a histological human Lung slide by BDORT, it was mapped the upper limb in 41 healthy individuals. There were almost identical matches in all points in 26 subjects (63.4%). In 15 subjects there were no identical matches at any point (36.5%). In all cases of no identical matches of the points, the new Lu1 point is displaced in the direction of midpoint of thorax below the clavicle. On the arm there was a medially deviation in comparison to the line obtained from the TCM points, for example the new Lu9 point was located on the midpoint of the wrist.


Subject(s)
Acupuncture Points , Electromagnetic Fields , Meridians , Adolescent , Adult , Aged , Child , Female , Humans , Lung/physiology , Male , Middle Aged , Young Adult
9.
Rev Sci Instrum ; 81(2): 02A306, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20192327

ABSTRACT

We developed an electron cyclotron resonance ion source (ECRIS) for new materials production on nanoscale. Our main target is the endohedral fullerenes, which have potential in medical care, biotechnology, and nanotechnology. In particular, iron-encapsulated fullerene can be applied as a contrast material for magnetic resonance imaging or microwave heat therapy. Thus, our new ECRIS is named the Bio-Nano ECRIS. In this article, the recent progress of the development of the Bio-Nano ECRIS is reported: (i) iron ion beam production using induction heating oven and (ii) optimization of singly charged C(60) ion beam production.


Subject(s)
Cyclotrons , Electrons , Nanotechnology/methods , Fullerenes/chemistry , Hot Temperature , Nanotechnology/instrumentation
10.
J Oral Rehabil ; 36(5): 362-7, 2009 May.
Article in English | MEDLINE | ID: mdl-19210680

ABSTRACT

This study was conducted to evaluate the effect of polyphosphoric acid (PPA) treatment on bone regeneration around titanium (Ti) implants in vivo. Adsorption of PPA by Ti was achieved by immersing Ti implants (2 mm in diameter, 4 mm in length) in different concentrations of PPA solution (0, 1 and 10 wt%) for 24 h at 37 degrees C after proper Ti surface cleaning. The treated Ti implants were implanted on 8-week-old-male rat (n = 30) tibiae. Two or four weeks after implantation, all animals were deeply anaesthetized and underwent perfusion fixation. Ten specimens in each condition were further immersed in the same fixative for 1 week and eventually embedded in polyester resin. Afterwards, undecalcified sections were ground to a thickness of approximately 70 microm parallel to the long axis of the implant. The sections were stained with basic fuchsine and methylene blue and then examined by light microscopy. For quantitative evaluation of bone regeneration around the implants, the bone-implant contact ratio (BICR) was determined. Polyphosphoric acid treatment of the Ti implant surface significantly enhanced direct bone contact to the Ti surface. Especially, the BICRs of the 1 wt% PPA-treated Ti implants were significantly higher than those of the control untreated Ti implants, both 2 and 4 weeks after implantation. At 4 weeks, 10 wt% PPA-treated implants also significantly increased the BICR as compared to that of the untreated Ti implants. These results suggest that PPA treatment promotes osteoconductivity of Ti in vivo.


Subject(s)
Bone Regeneration/drug effects , Implants, Experimental , Phosphoric Acids/pharmacology , Polymers/pharmacology , Titanium , Animals , Dose-Response Relationship, Drug , Drug Evaluation, Preclinical/methods , Male , Osseointegration/drug effects , Rats , Rats, Wistar , Tibia/anatomy & histology , Tibia/drug effects , Tibia/surgery
11.
Kidney Int ; 70(3): 471-6, 2006 Aug.
Article in English | MEDLINE | ID: mdl-16775605

ABSTRACT

A decrease in renal synthesis of nitric oxide (NO) in the progression of diabetic nephropathy has been documented. As (6R)-5,6,7,8-tetrahydrobiopterin (BH4) is an essential cofactor of NO synthase, we investigated whether BH4 deficiency is involved in the pathogenesis of nephropathy. Ten-week-old Otsuka Long-Evans Tokushima Fatty (OLETF) rats were used as a type II diabetic model, and Long-Evans Tokushima Otsuka (LETO) rats as the healthy controls. OLETF rats were orally treated with BH4 (10 mg/kg daily) or with water from 10 to 61 weeks of age. In another experiment, OLETF rats were treated orally with a calcium channel blocker, benidipine (5 mg/kg daily), or with 0.3% carboxymethyl cellulose (nontreated) from 10 to 52 weeks of age. Proteinuria was observed periodically, and at the end of the study, BH4 level and GTP cyclohydrolase I (GTPCH) activity in the kidney were measured. Proteinuria was observed at 13 weeks of age in the OLETF rats, and deteriorated until 61 weeks of age. Supplemental BH4 reduced the proteinuria. At 52 weeks of age, GTPCH activity and the BH4 level were decreased in the plasma and kidneys of OLETF rats, whereas they were significantly higher in the benidipine group than in the nontreated group. Proteinuria was milder in the benidipine group than in the nontreated group, without a concomitant decrease in blood pressure. Histologically observed glomerulosclerosis was mild in the BH4 and benidipine groups. In type II diabetic rats, renal BH4 is considered to play a crucial role in the pathogenesis of diabetic nephropathy. Benidipine was found to preserve BH4 levels, suggesting therapeutic renoprotective effects.


Subject(s)
Biopterins/analogs & derivatives , Diabetic Nephropathies/etiology , Diabetic Nephropathies/metabolism , Kidney/metabolism , Animals , Biopterins/blood , Biopterins/deficiency , Biopterins/pharmacology , Blood Glucose , Blood Pressure , Body Weight , Calcium Channel Blockers/pharmacology , Creatinine/blood , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/drug therapy , Diabetes Mellitus, Type 2/metabolism , Diabetic Nephropathies/drug therapy , Dihydropyridines/pharmacology , Kidney/pathology , Male , Nitric Oxide/metabolism , Proteinuria/drug therapy , Proteinuria/etiology , Proteinuria/metabolism , Rats , Rats, Inbred OLETF , Rats, Long-Evans
12.
Water Sci Technol ; 53(6): 21-7, 2006.
Article in English | MEDLINE | ID: mdl-16749435

ABSTRACT

An anaerobic/aerobic/anoxic/aerobic sequencing batch reactor (SBR) was operated with municipal wastewater to investigate the effect of nitrite on biological phosphorus removal (BPR). When nitrite accumulated, aerobic phosphate uptake activity significantly decreased and, in case of hard exposure to nitrite, BPR severely deteriorated. The interesting observation was that the relative anoxic activity of phosphate accumulating organisms (PAOs) increased after nitrite exposure. Moreover batch tests of aerobic phosphate uptake in the presence/absence of nitrite indicated that PAOs with the higher relative anoxic activity are less sensitive to nitrite exposure. From these results, we concluded that BPR is sensitive to nitrite exposure, but BPR containing PAOs with the higher relative anoxic activity is possibly more stable against nitrite than BPR containing PAOs with the lower relative anoxic activity.


Subject(s)
Nitrites/chemistry , Phosphates/chemistry , Waste Disposal, Fluid/methods , Water Purification/methods , Bacteria, Anaerobic/metabolism , Biodegradation, Environmental , Bioreactors , Nitrogen , Phosphorus , Polyphosphates/chemistry , Sewage
13.
Dis Esophagus ; 18(4): 283-6, 2005.
Article in English | MEDLINE | ID: mdl-16128788

ABSTRACT

We report on a 75-year-old woman with an isolated colonic hernia through the esophageal hernia. The patient had suffered from cough, palpitation and dyspnea. A chest X-ray showed a colon loop gas in the mediastinum. Simultaneous barium swallow and enema showed the herniation of the only transverse colon into the mediastinum and displacement of the distal esophagus by the migrated colon. The patient underwent an open-mesh cruroplasty and a Hill's posterior gastropexy. The postoperative clinical course was uneventful. The patient has cessation of the symptoms. To our knowledge, there are only five reports presenting patients with isolated colonic hernia through the esophageal hiatus, including our case.


Subject(s)
Colon, Transverse/diagnostic imaging , Colonic Diseases/diagnostic imaging , Hernia, Hiatal/diagnostic imaging , Hernia/diagnostic imaging , Aged , Barium Sulfate , Contrast Media , Female , Humans , Radiography, Thoracic
14.
J Neurol Neurosurg Psychiatry ; 75(3): 485-7, 2004 Mar.
Article in English | MEDLINE | ID: mdl-14966171

ABSTRACT

Two Japanese sporadic Creutzfeld-Jakob disease (sCJD) patients with valine homozygosity at codon 129 of the prion protein gene and protease-resistant prion protein (PrP(Sc)) type 2 (VV2) are described. In contrast with Western countries, this type of sCJD is very rare in Japan. In 123 sCJD cases, only two were recognised as VV2 by the Japanese CJD surveillance committee. The clinical symptoms and pathological findings of the patients were similar to those of European and US patients. The noteworthy finding of diffusion weighted MRI (DWI) was that an abnormal high intensity covered a wide range of the thalamus including the dorsomedial nucleus, the pulvinar, and the ventral anterior, lateral, and posterolateral nuclei. This thalamic pattern has not been recognised in sCJD with methionine homozygosity and PrP(Sc) type 1 (MM1) or methionine/valine heterozygosity and PrP(Sc) type 1 (MV1) which comprises the vast majority of sCJD. This finding may be characteristic to VV2 and may distinguish it from MM1, MV1, and variant CJD. DWI can provide a very important clue for the antemortem diagnosis of VV2 subjects.


Subject(s)
Creutzfeldt-Jakob Syndrome/genetics , Creutzfeldt-Jakob Syndrome/pathology , PrPSc Proteins/genetics , Prions/genetics , Thalamus/pathology , Valine/analysis , Aged , Autopsy , Codon/genetics , Diffusion Magnetic Resonance Imaging , Female , Humans , Japan , Male
15.
J Cardiovasc Electrophysiol ; 12(8): 939-45, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11513447

ABSTRACT

INTRODUCTION: Preexisting changes in repolarization properties play an important role in T wave abnormalities (cardiac memory) after ablation in patients with Wolff-Parkinson-White (WPW) syndrome. However, no report has provided direct evidence for prolongation of action potential duration (APD) over a preexcited region before and after ablation. METHODS AND RESULTS: We studied 10 patients with ventricular preexcitation due to a left-sided accessory pathway (AP) (group M) and 12 patients with concealed left-sided AP (group C) to clarify prolongation of APD using activation-recovery intervals (ARIs) from epicardial and endocardial unipolar electrograms in patients with WPW syndrome. ARI was calculated from unipolar electrograms at the His bundle and the coronary sinus adjacent to the AP during atrial pacing (100 beats/min) before and 30 minutes after ablation. Before ablation, ARIs at the AP site were significantly longer in group M than in group C (255+/-21 msec vs 211+/-24 msec; P < 0.01), whereas ARIs at the His bundle did not differ between the two groups (255+/-20 msec vs 245+/-27 msec; P = NS). After ablation, group M showed no significant changes in ARIs at the AP and His bundle (256+/-19 msec and 253+/-15 msec) compared with before ablation. CONCLUSION: We found by direct analysis of ARIs from the epicardium that APD prolongation over the preexcited region was present before catheter ablation and persisted after catheter ablation. The gradual changes in repolarization properties, including APD prolongation after discontinuation of AP, may be one mechanism of cardiac memory after catheter ablation in patients with WPW syndrome.


Subject(s)
Action Potentials/physiology , Catheter Ablation , Recovery of Function/physiology , Wolff-Parkinson-White Syndrome/surgery , Adult , Aged , Body Surface Potential Mapping , Bundle of His/physiopathology , Electrophysiologic Techniques, Cardiac , Female , Humans , Japan , Male , Middle Aged , Time Factors
16.
J Oral Sci ; 43(2): 85-9, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11515602

ABSTRACT

A histopathological and analytical study of a permanent tooth from a patient with cleidocranial dysostosis (CCD) was performed. The patient was a 47-year-old woman, who had 10 erupted permanent teeth and 2 partially erupted and 19 completely impacted teeth, including supernumerary teeth. The erupted right upper premolar was extracted and observed using a light microscope and an electron probe X-ray microanalyzer (EPMA). Findings showed enamel hypoplasia, predominantly irregular globular dentin and Tomes' granular layer, and a complete lack of cellular cementum in the ground section. The incremental von Ebner and counter Owen lines were obscure. Comparative quantitative analysis using the EPMA showed that the quantities of calcium and phosphate were lower in the enamel and dentin than those of the control sample.


Subject(s)
Bicuspid/abnormalities , Cleidocranial Dysplasia/complications , Bicuspid/pathology , Calcium/analysis , Dental Cementum/abnormalities , Dental Enamel/chemistry , Dental Enamel Hypoplasia/metabolism , Dental Enamel Hypoplasia/pathology , Dentin/abnormalities , Dentin/chemistry , Electron Probe Microanalysis , Female , Humans , Middle Aged , Phosphorus/analysis , Tooth, Impacted/complications , Tooth, Supernumerary/complications , Tooth, Unerupted/complications
17.
No To Shinkei ; 53(1): 55-9, 2001 Jan.
Article in Japanese | MEDLINE | ID: mdl-11211732

ABSTRACT

Recently we reported the frequent occurrence of hemorrhages in the dorsal root ganglia of congenitally hydrocephalic HTX rats, an animal model of human congenital hydrocephalus. Therefore, we hypothesized that sensory disturbance might be present in these rats. In order to evaluate the sensory abnormality quantitatively, we injected 50 microliters of 5% formalin into the footpad of the left hind paw of hydrocephalic (n = 5) and non-hydrocephalic HTX rats (n = 5) and Wistar rats (n = 5) on postnatal days 17-23, and then recorded the licking response time for 60 min after injection. The mean licking time in the early (0-10 min) and late (10-60 min) phases was significantly longer in hydrocephalic HTX rats than in non-hydrocephalic HTX and Wistar rats (P < 0.05). Histologically, hemorrhages in the dorsal root ganglia were found in all five hydrocephalic animals, of which two had shown thalamic degeneration. These findings suggest that lesions in the dorsal root ganglia and thalamus may correspond to the sensory disturbance observed in congenitally hydrocephalic HTX rats.


Subject(s)
Ganglia, Spinal/pathology , Hemorrhage/pathology , Hydrocephalus/pathology , Sensation Disorders/pathology , Animals , Disease Models, Animal , Rats , Rats, Inbred WKY , Thalamus/pathology
18.
Acta Med Okayama ; 55(6): 349-55, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11779097

ABSTRACT

Hepatic encephalopathy is one of the major complications in decompensated liver cirrhosis. The current study was conducted to clarify the mechanisms of zinc deficiency in liver cirrhosis and its involvement in hepatic encephalopathy via ammonia metabolism. Ten patients each with compensated or decompensated liver cirrhosis and 11 healthy volunteers were enrolled in the study. Serum zinc levels and its daily urinary excretion were measured, an oral zinc-tolerance test was performed to examine zinc malabsorption, and the effects of diuretics on zinc excretion and of zinc supplementation on ammonia metabolism in the skeletal muscle were studied. The mean serum zinc levels in patients with decompensated liver cirrhosis were found to be significantly lower than the levels in controls and patients with compensated liver cirrhosis. The serum zinc levels were inversely correlated with blood ammonia in the fasting state. In the oral zinc-tolerance test, the percent increase in serum zinc levels 120 and 180 min after ingestion was less in cirrhotic patients than in controls. A diuretic administration resulted in a significant reduction in serum zinc levels. An increased uptake of ammonia by and an increased release of glutamine from leg skeletal muscle after oral supplementation of zinc sulfate were evident. Taken together, zinc deficiency in decompensated cirrhotic patients appears to be due to low absorption and to high urinary excretion, for which excessive diuretic administration is, in part, responsible, and zinc supplementation might play an important role in the prevention of hepatic encephalopathy by activating glutamine synthetase.


Subject(s)
Ammonia/metabolism , Liver Cirrhosis/drug therapy , Liver Cirrhosis/metabolism , Zinc/deficiency , Zinc/therapeutic use , Ammonia/blood , Glutamine/metabolism , Humans , Muscle, Skeletal/metabolism , Zinc/blood , Zinc/urine
19.
Jpn J Cancer Res ; 91(4): 383-9, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10804285

ABSTRACT

We investigated the effect of a Chinese medicinal herb, Acanthopanax gracilistylus (AG), extract (E) on the growth of human tumor cell lines in vitro. AGE markedly inhibited the proliferation of several tumor cell lines such as MT-2, Raji, HL-60, TMK-1 and HSC-2. The activity was associated with a protein of 60 kDa, which was purified by gel-filtration chromatography. Cell viability analyses indicated that the treatment with AGE inhibits cell proliferation, but does not induce cell death. The mechanism of AGE-induced inhibition of tumor cell growth involves arrest of the cell cycle at the G(0) / G(1) stage without a direct cytotoxic effect. The cell cycle arrest induced by AGE was accompanied by a decrease of phosphorylated retinoblastoma (Rb) protein. Furthermore, cyclin-dependent kinases 2 and 4 (Cdk2 and Cdk4), which are involved in the phosphorylation of Rb, were also decreased. These results suggest that AGE inhibits tumor cell growth by affecting phosphorylated Rb proteins and Cdks.


Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , CDC2-CDC28 Kinases , Drugs, Chinese Herbal/pharmacology , Proto-Oncogene Proteins , Cell Cycle/drug effects , Cell Division/drug effects , Cyclin-Dependent Kinase 2 , Cyclin-Dependent Kinase 4 , Cyclin-Dependent Kinases/metabolism , Humans , Phosphorylation , Plant Extracts/pharmacology , Protein Serine-Threonine Kinases/metabolism , Retinoblastoma Protein/metabolism , Tumor Cells, Cultured
20.
J Dent Res ; 79(2): 709-14, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10728971

ABSTRACT

For many years, glass-polyalkenoate cements have been described as possessing the unique properties of self-adherence to human hard tissues, such as bones or teeth. However, direct experimental evidence to prove the existence of chemical bonding has not been advanced. X-ray Photoelectron Spectroscopy (XPS) was used to analyze the chemical interaction of a synthesized polyalkenoic acid with enamel and synthetic hydroxyapatite. For both enamel and hydroxyapatite, the peak representing the carboxyl groups of the polyalkenoic acid was detected to have significantly shifted to a lower binding energy. De-convolution of this shifted peak disclosed two components with a peak representing unreacted carboxyl groups and a peak suggesting chemical bonding to hydroxyapatite. On average, 67.5% of the carboxyl groups of the polyalkenoic acid were measured to have bonded to hydroxyapatite. XPS of hydroxyapatite also disclosed its surface to be enriched in calcium and decreased in phosphorus, indicating that phosphorus was extracted at a relatively higher rate than calcium. Analysis of these data supports the mechanism in which carboxylic groups replace phosphate ions (PO4(3-)) of the substrate and make ionic bonds with calcium ions of hydroxyapatite. It is concluded that an ultrathin layer of a polyalkenoic acid can be prepared on a hydroxyapatite-based substrate by careful removal of non-bonded molecules. With this specimen-processing method, XPS not only provided direct evidence of chemical bonding, but also enabled us to quantify the percentages of functional groups of the polyalkenoic acids that bonded to calcium of hydroxyapatite.


Subject(s)
Biocompatible Materials/chemistry , Dental Bonding , Glass Ionomer Cements/chemistry , Tooth/chemistry , Binding Sites , Bone Cements/chemistry , Calcium/chemistry , Carbon Dioxide/chemistry , Chemical Phenomena , Chemistry, Physical , Dental Cements/chemistry , Dental Enamel/chemistry , Durapatite/chemistry , Electron Probe Microanalysis , Free Radicals/chemistry , Humans , Phosphates/chemistry , Phosphorus/chemistry
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