No abstract available.
Brain Ischemia* ; Glutamic Acid* ; Microdialysis ; Nitric Oxide Synthase* ; Nitric Oxide*

No abstract available.
Extracorporeal Membrane Oxygenation ; Humans ; Inhalation ; Nitric Acid

STATEMENT OF PROBLEM: Titanium has many advantages of high biocompatibility, physical porperties, low-weight, low price and radiolucency, but it is incompatible with conventional dental porcelain due to titanium's oxidative nature. Many previous studies have shown that they used the method of sandblast for surface treatment prior to porcelain application, the researchs are processing about the method of acid etching or surface coating. PURPOSE: The purpose of this research is to study the effect on bond strength between titanium and porcelain when using macro-surface treatment and micro-surface treatment and macro and micro surface treatment . MATERIAL AND METHOD: In this study, we evaluated the bond strength by using 3-point bending test based on ISO 9693 after classified 7 groups - group P : polished with #1200 grit SiC paper, group SS : sandblasted with 50 micrometer aluminum oxides, group LS : sandblasted with 250 micrometer alumium oxides, group HC : treated with 10 % hydrochloric acid, group NF : treated with 17% solution of fluoric acid and nitric acid, group SHC : treated with 10 % hydrochloric aicd after sandblsting with 50 micrometer alumium oxides, group SNF : treated with 17 % solution of fluoric acid and nitric acid. RESULTS: Within the confines of our research, the following results can be deduced. 1. Group SS which was sandblasted with 50 micrometer aluminum oxides showed the highest bond strength of 61.74 MPa and significant differences(P<0.05). The bond strengths with porcelain in groups treated acid etching after sandblasting decreased more preferable than the group treated with sandblasting only. It gives significant differences(P<0.05). 2. After surface treatments, the group treated with sandblasting showed irregular aspect formed many undercuts, in the SEM photographs. The group treated with hydrochloric acid had the sharp serrated surfaces, the group treated with the solution of fluoric acid and nitric acid had the smooth surfaces, the group with sandblasting and hydrochloric acid had irrigular and porous structure, the group with sandblasting and the solution of fluoric acid and nitric acid had craterlike surfaces. But all of the groups treated with acid etching was not found and undercut. CONCLUSION: In above results, average surface roughness increase, bond strength also increase, but surface topographs influences more greatly on bond strengths.
Aluminum ; Dental Porcelain ; Hydrochloric Acid ; Nitric Acid ; Oxides ; Titanium

PURPOSE: To investigate the effects of valproic acid on the production of nitric oxide (NO) and expression of endothelial nitric oxide synthase (eNOS) in cultured human trabecular meshwork cells (HTMC). METHODS: Primarily cultured HTMC were exposed to 0.25, 0.5, and 1.0 mM valproic acid for 6, 12, and 24 hours. Expression of eNOS mRNA was assessed with Reverse transcription-polymerase chain reaction, and production of NO was assessed with Griess assay. Cellular survival was assessed with the 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide (MTT) assay. RESULTS: Valproic acid at concentrations of 0.25, 0.5, 1.0 mM did not affect the cellular survival of HTMC significantly after exposure for 24 hours. Valproic acid increased NO production in a dose- and time-dependent manner. Also, valproic acid increased the degree of eNOS mRNA expression in a dose-dependent manner in HTMC. CONCLUSIONS: Valproic acid increases production of NO and expression of eNOS mRNA in HTMC. Thus, valproic acid might increase aqueous outflow through the trabecular meshwork.
Humans ; Nitric Oxide Synthase Type III ; Nitric Oxide Synthase ; Nitric Oxide ; RNA, Messenger ; Trabecular Meshwork ; Valproic Acid

Purpose: This study aims to get the fundamental data which is necessary to the development direction of implant surface treatment hereafter, based on the understanding the surface structure and properties of titanium which is suitable for the absorption of initial tissue fluid by researching effects of additional surface treatments for sandblasted with large grit and acid-etched(SLA) titanium on surface micro-roughness, static wettability, fibronectin adsorption. Materials and Method: In the Control groups, the commercial pure titanium disks which is 10mm in diameter and 2mm in thickness were treated with HCI after sandblasting with 50micrometer Al2O3. The experiment groups were made an experiment each by being treated with 1) 22.5% nitric acid according to SLA+ASTM F86 protocol, 2) SLA+30% peroxide, 3) SLA+NaOH, 4) SLA+Oxalic acid, and 5) SLA+600degree C heating. In each group, the value of Ra and RMS which are the gauges of surface roughness was measured, surface wettability was measured by analyzing with Sessile drop method, and fibronectin adsorption was measured with immunological assay. The significance of each group was verified by (SPSS, ver.10.0 SPSS Inc.) Kruskal-Wallis Test.(alpha=0.05) And the correlation significance between Surface micro-roughness and surface wettability, surface roughness and fibronectin adsorption, and surface wettability and fibronectin adsorption was tested by Spearman's correlation analysis. Result: All measure groups showed the significant differences in surface micro-roughness, surface wettability, and fibronectin adsorption.(p<0.05) There was no significance in correlation among the surface micro-roughness, surface wettability, and fibronectin adsorption.(p>0.05) Conclusion: Surface micro-roughness and surface wettability rarely affected the absorption of initial tissue fluid on the surface of titanium.
Absorption ; Adsorption* ; Fibronectins* ; Heating ; Hot Temperature ; Nitric Acid ; Titanium* ; Wettability*

OBJECTIVETo evaluate shrinkage range of cleared teeth caused by nitric acid with different temperature and concentration.

METHODS48 human teeth were root canal-prepared and filled, then randomly and averagely divided into six groups on the basis of temperature and density of nitric acid and the condition of whether or not added the oscillate. Group A was 20 degrees C with 6% nitric acid, group B was 20 degrees C with 6% nitric acid and oscillate, group C was 20 degrees C with 3% nitric acid, group D was 20 degrees C with 3% nitric acid and oscillate, group E was 30 degrees C with 6% nitric acid and oscillate, group F was 30 degrees C with 3% nitric acid and oscillate. After achieving the standard of the decalcification, all the specimens were gradually dehydrated, and then cleared and conserved using methyl salicylate. Time-consumed and shrinkage range of all the specimens were recorded and analyzed.

RESULTSThe time of decalcification in group E was the fastest, then was group F, group B. Group C was the last one. The anastole of the specimens was group E > group B > group A, group F > group D > group C, group B > group D, group E > group D, there was significant difference (P < 0.05). Group C had significant difference with other groups (P < 0.05). The anastole rate of the specimens had no significant difference between group A and group B, group C and group D, group B and group F, group D and group F.

CONCLUSIONIn 20 degrees C, 3% nitric acid with oscillate to carry out the decalcification can use less time and get less anastole. The result of the tooth-clearing technique is the best.

Uric acid (UA) is the final product of purine metabolism in human body,and its metabolic disorder will induce hyperuricemia (HUA).The occurrence and development of HUA are associated with a variety of pathological mechanisms such as oxidative stress injury,activation of inflammatory cytokines,and activation of renin-angiotensin-aldosterone system.These mechanisms directly or indirectly affect the bioavailability of endogenous nitric oxide (NO).The decrease in NO bioavailability is common in the diseases with high concentration of UA as an independent risk factor.In this review,we summarize the mechanisms by which high concentrations of UA affect the endogenous NO bioavailability,with a focus on the mechanisms of high-concentration UA in decreasing the synthesis and/or increasing the consumption of NO.This review aims to provide references for alleviating the multisystem symptoms and improving the prognosis of HUA,and lay a theoretical foundation for in-depth study of the correlations between HUA and other metabolic diseases.
Humans ; Nitric Oxide ; Uric Acid ; Hyperuricemia ; Biological Availability ; Cytokines

The pure titanium disks were divided into three groups and etched for 30 minutes with HNO3, hot H2SO4/H2O2 or hot H2SO4/HCl respectively. The treated disks were studied and analyzed with scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS). The disks etched with HNO3 had a smooth surface, while those etched with hot H2SO4/H2O2 or hot H2SO4/HCl had rough surfaces, and the surface etched with hot H2SO4/HCl had larger micropores. The XPS analysis demonstrated that the main elements of the surface in three groups were titanium, oxygen and carbon. The carbon concentration was the lowest on the surface etched with hot H2SO4/H2O2 and the highest on that etched with hot H2SO4/HCl. The substances were TiO2, Ti2O3, TiO and metal Ti on the surface etched with HNO3 or hot H2SO4/H2O2. Only TiO2 was detected on the surface etched with hot H2SO4/HCl.
Hydrochloric Acid ; Hydrogen Peroxide ; Metallurgy ; methods ; Nitric Acid ; Oxides ; Sulfuric Acids ; Surface Properties ; Titanium ; chemistry

Endothelial dysfunction is known to be early stage of atherosclerosis and its presence leads to poor prognosis. Recently many basic researchs were done to elucidate the basic mechanism related to endothelial nitric oxide synthase (eNOS). eNOS is composed of dimer, between which calmodulin binding domain is located. This area plays important role in producing NO with BH4 (tetrahydrobiopteryn as a co factor). In the presence of excess of superoxide from NADPH oxidase, NO binds with superoxide to be peroxynitrite. BH4 is converted to BH2 in the presence of peroxynitrite and eNOSdimer dissociates to monomer, which is called uncoupling. Uncoupled eNOS produces superoxide and it results in endothelial dysfunction. NO deficiency is related to the decreased number of peripheral endothelial progenitor cell and HDL-cholesterol is known to stimulate eNOS. This would be new field of research relating eNOS to atherogenesis and eNOS's role in prevention of cardiovascular disease.
Atherosclerosis ; Calmodulin ; Cardiovascular Diseases ; NADPH Oxidase ; Nitric Oxide ; Nitric Oxide Synthase Type III ; Peroxynitrous Acid ; Prognosis ; Stem Cells ; Superoxides

We have investigated the neural cell damage and the change in the expression of NOS in the rat hippocampus, one of the brain structures most vulnerable to seizures. Rats were injected with kainic acid (KA) and sacrificed 6 h, 1 d, 3 d and 6 d after KA administration. The neural cell damage and the expression pattern of NOS was studied using silver impregnation, NADPH-diaphorase (NADPH-d) histochemistry and reverse transcription-polymerase chain reaction (RT-PCR) analysis. Silver impregnation revealed that kainic acid caused pyramical cell damage which was most severe in the CA1/CA2 subfield and hilus and to a lesser degree in the CA3 region. The optical densities of NADPH-d-positive neurons in the CA1, CA3 and dentate gyrus (DG) regions of the hippocampus were shown to have increased in samples obtained 1 d and 3 d after injection of KA. The number of NADPH-d-positive neurons in the CA1 and CA3 regions of the hippocampus was shown to have decreased in samples obtained 3 d and 6 d after injection of KA. However, the number of NADPH-d-positive neurons in the DG region did not change significantly. The increase in the levels of nNOS, iNOS and eNOS mRNA reached maximal values in samples obtained 1 d after KA treatment. Our findings indicate that the KA-induced seizures induce neural cell damage, increase NOS activity and upregulate the expression of NOS mRNA, which suggests the possibility of a functional role of NOS in bringing about changes in the cells in the hippocampus following seizures.
Animals ; Brain ; Dentate Gyrus ; Hippocampus* ; Kainic Acid ; Neurons ; Nitric Oxide Synthase Type I ; Nitric Oxide Synthase* ; Nitric Oxide* ; Rats* ; RNA, Messenger ; Seizures* ; Silver