The isolated rabbit kidney was perfused with 4 kinds of perfusates which had different ionic compositions, in order to investigate the effects of divalent cations, Mg and Ca, on the renal autoregulation. Four kinds of perfusates are full-balanced perfusate (FBP), perfusate subtracted both CaCl2and MgCI2 from FBP, perfusate subtracted only CaCI, from FBP, and perfusate subtracted only MgCl2 from FBP. The composition of FBP is 6% hydroxyethyl starch in 0.9% NaCl (McGaw Lab. USA) containing Na-acetate 5.0, K2HPO4 5.0, CaCls 1.2, MgCl2 0.5, and glucose 5.O mM/L. Renal Perfusate Flow (RPF) as related to various renal arterial perfusion pressure (RAP) was directly measured with flow-meter attached to the perfusion system. Total renal resistance (Rr) was calculated from RAP & RPF (RT=RAP/RPF). Alterations in renal autoregulation, when different perfusates were perfused, were estimated by pressure-flow curve in every run of perfusion experiments. The results obtained were as follows: 1) Kidney perfused with FBP revealed autoregulation within the range of 100~180 mmHg RAP. Renal Perfusate Flow in the autoregulation zone was 5.0 ml,min/gm. 2) The autoregulation was not appeared in the experiments perfused with the solution subtracted both CaCl2 and MgCI2 from FBP. 3) Kidney perfused with FBP-CaCI2 revealed the autoregulation, which had the autoregulation zone of 110~180 mmHg RAP, and 5. 5 m1/min/gm RPF. However, it was not present in the kidney perfused with FBP-MgCl2. 4) The time course of autoregulation was observed on the pressure-flow curve; autoregulation was continued approximately for 15 minutes, and then deteriorated rapidly. 5) Total renal resistance calculated was proportionately increased as the RAP increased within the regulation zone. Below and above the zone, it was almost inversely related to the RAP. From the above results, it was concluded that Mg is the essential factor in the renal autoregulation and suggested that Mg could have a key role on the neuromuscular transmission, excitability of muscular cell membrane, or the process of intracellular contraction.
Cations, Divalent ; Cell Membrane ; Glucose ; Homeostasis* ; Ions* ; Kidney* ; Magnesium Chloride ; Perfusion ; Starch

TRPM7, a cation channel protein permeable to various metal ions such as Mg2+, is ubiquitously expressed in variety of cells including lymphocytes. The activity of TRPM7 is tightly regulated by intracellular Mg2+, thus named Mg2+-inhibited cation (MIC) current, and its expression is known to be critical for the viability and proliferation of B lymphocytes. In this study, the level of MIC current was compared between immature (WEHI-231) and mature (Bal-17) B lymphocytes. In both cell types, an intracellular dialysis with Mg2+-free solution (140 mM CsCl) induced an outwardly-rectifying MIC current. The peak amplitude of MIC current and the permeability to divalent cation (Mn2+) were several fold higher in Bal-17 than WEHI-231. Also, the level of mRNAs for TRPM7, a molecular correspondence of the MIC channel, was significantly higher in Bal-17 cells. The amplitude of MIC was further increased, and the relation between current and voltage became linear under divalent cation-free conditions, demonstrating typical properties of the TRPM7. The stimulation of B cell receptors (BCR) by ligation with antibodies did not change the amplitude of MIC current. Also, increase of extracellular [Mg2+]c to enhance the Mg2+ influx did not affect the BCR ligation-induced death of WEHI-231 cells. Although the level of TRPM7 was not directly related with the cell death of immature B cells, the remarkable difference of TRPM7 might indicate a fundamental change in the permeability to divalent cations during the development of B cells.
Antibodies ; B-Lymphocytes* ; Cations, Divalent ; Cell Death ; Dialysis ; Ions ; Ligation ; Lymphocytes ; Permeability ; Precursor Cells, B-Lymphoid ; RNA, Messenger

Transient receptor potential vanilloid type-1 channel (TRPV1) is a non-selective cation channel with a preference for calcium ions that is able to sense a vast range of endogenous physical and chemical stimuli and plays an important role in transducing the sensations of noxious heat and pain signaling. Recent studies showed that TRPV1 is widely expressed in different tissues and organs beyond the sensory nerves and has multiple biological effects that are involved in functional regulation in the pancreas, blood vessel, adipose tissue and liver. To further understand the link between TRPV1 and cardiometabolic diseases, we reviewed the role of TRPV1 in hypertension, diabetes, obesity, and dyslipidemia. This review provides new insights into the involvement of TRPV1 channels in the pathogenesis of cardiometabolic disorders and implicates this channel as a potential therapeutic target for the management of cardiometabolic diseases.
Adipose Tissue ; Aluminum Hydroxide ; Blood Vessels ; Calcium ; Capsaicin ; Carbonates ; Dyslipidemias ; Glycosaminoglycans ; Hot Temperature ; Hypertension ; Ions ; Liver ; Obesity ; Pancreas ; Sensation

Stereoselective transformation of Baylis-Hillman acetates 1 into corresponding (Z)-allyl iodides 2 has been achieved by treatment of 1 with samarium triiodide in THF. Remarkable rate acceleration of samarium triiodide-mediated iodination of 1 was found when ionic liquid 1-n-butyl-3-methyl-imidazolium tetrafluroborate ([bmim]BF(4)) was used as reaction media in stead of THF. This novel approach proceeds readily at 50 degrees C within a few minutes to afford (Z)-allyl iodides 2 in excellent yields. A mechanism involving stereoselective iodination of the acetates of Baylis-Hillman adducts by samarium triiodide is described, in which a six-membered ring transition state played a key role in the stereoselective formation of 2.
Acetates ; chemistry ; Iodides ; chemical synthesis ; Ions ; Kinetics ; Samarium ; chemistry ; Solutions

Porphyromonas gingivalis is strongly implicated in the pathogenesis of adult periodontitis, the major cause of tooth loss in adults. Use of an antibacterial agent controlling P. gingivalis as a periodontal therapeutic agent has been rationalized. The present study was performed to observe the antibacterial effect of inorganic polyphosphates (polyP) on P. gingivalis. P. gingivalis 2561 was grown in half-strength brain-heart infusion broth containing hemin and vitamin K with or without polyP. Minimal inhibitory concentration (MIC) of polyP with various chain lengths was determined by measuring the absorbance of the grown cells at 540 nm. MIC of polyP for the bacterium was determined to be 0.05%. The effect of polyP with a chain length of 75 (polyP 75) was further examined. PolyP 75 added to the growing culture of P. gingivalis at its exponential phase was as effective in inhibiting the growth of P. gingivalis as polyP 75 added at the very beginning of the culture. More than 99% of the cells lost their viability determined by viable cell count when polyP 75 was added to the culture of growing P. gingivalis at the concentration of 0.06%, suggesting that polyP 75 has a bactericidal effect on the bacterium. Intracellular nucleotide release from the cells was increased by approx. 20% in the presence of polyP 75 but was not reversed by the addition of divalent cations like Ca++ and Mg++. Under the transmission electron microscope, only a small number of the growing P. gingivalis cells were actually lysed. However, the majority of the cells appeared to be atypical in their shape, demonstrating accumulation of highly electron-dense granules and bodies of condensed nucleic acid-like material in the cytoplasm. In the presence of polyP 75, the protein profile of P. gingivalis was changed as determined by SDS-polyacrylamide gel electrophoresis and immunoblot, and the proteolytic activity of the bacterium demostrated on the zymograms was decreased. The overall results suggest that polyP have a strong bactericidal activity against P. gingivalis in which lysis in relation to chelation may not play the major role but unknown mechanism that possibly affects the viability of the bacterium may be involved. PolyP may be used as an agent for prevention and treatment of periodontitis.
Adult ; Cations, Divalent ; Cell Count ; Chronic Periodontitis ; Cytoplasm ; Electrophoresis ; Hemin ; Humans ; Periodontitis ; Polyphosphates* ; Polyps ; Porphyromonas gingivalis* ; Porphyromonas* ; Tooth Loss ; Vitamin K

Air ; analysis ; Anions ; analysis ; Chromatography, Ion Exchange ; Ions ; analysis ; Workplace

PURPOSE: Hydrofluoric acid(HF) is one of the most dangerous mineral acids with the dissociated fluoride ions. The initial corrosive burn is caused by free hydrogen ion, and the second and more severe burn is caused by penetration of fluoride ions into subcutaneous tissues. Silver is a cation producing dressing, an effective antimicrobial agent, but older silver-containing formulations are rapidly inactivated by wound environment, requiring frequent replenishment. But, Acticoat(R) is a relatively new form of silver dressing which helps avoid the problems of earlier agents. The aim of this study is to evaluate effects of Acticoat(R), silver-containing dressing on the treatment for HF injury wound. METHODS: From september 2006 to september 2007, the study was carried out with 10 patients who had HF partial thickness burns. Acticoat(R) dressing and 10% calcium gluconate wet gauze dressings in 10 cases. As a principle, in the emergency treatment, partial or complete removal of the nail and early bullectomy along with copious washing with normal saline was done, depending on the degree of HF invasion of the wound. Wound was dressed with Acticoat(R) and 10% calcium gluconate solution. The effect of dressing was investgated by serial bacterial culture and wound exudates assessment. RESULTS: We therefore reviewed 10 cases of HF- induced chemical burns and treatment principle. The 10 cases who came to the hospital nearly immediately after the injury healed completely without sequelae. CONCLUSION: As the industrial sector develops, the use of HF is increasing more and more, leading to increased incidences of HF-induced chemical burns. The education of patients regarding this subject should be empathized accordingly. In conclusion, Acticoat(R) dressing is a better choice for HF partial thickness burn injuries because of shorter healing time, less pain and more comfortable dressing.
Bandages ; Burns ; Burns, Chemical ; Calcium Gluconate ; Emergency Treatment ; Exudates and Transudates ; Fluorides ; Gluconates ; Humans ; Hydrofluoric Acid ; Incidence ; Ions ; Nails ; Patient Education as Topic ; Polyesters ; Polyethylenes ; Porphyrins ; Protons ; Silver ; Subcutaneous Tissue

OBJECTIVES: The aims of this study were to determine the total fluoride concentration and bioavailable fluoride concentration in different toothpastes, based on a newly suggested method by the International Organization for Standardization (ISO), and to compare the measured concentrations with the concentrations written on the packaging. METHODS: The concentrations of total fluoride (TF) and bioavailable fluoride (BF) were measured in six toothpastes. For the TF measurement, 1 g of each toothpaste was mixed with dipotassium hydrogen phosphate (K2HPO4), and hydrogen chloride (HCl) was placed. After 24 hours, the samples were centrifuged and total ionic strength adjustment buffer (TISAB) solution was added. For the BF measurement, the toothpaste was mixed with K2HPO4 for only 1 minute. The samples were centrifuged, and then HCl was placed and allowed to stand for 24 hours. The TISAB solution was added subsequently. The concentration of fluoride ions was measured using a fluoride ion-selective electrode and calculated against a standard curve. RESULTS: The six toothpastes were composed of different fluoride compounds and abrasives. The measured TF concentration ranged from 624.99 ppm to 1,353.00 ppm, and the similarity to the declared fluoride concentration ranged from 53.48% to 93.31%. The measured BF concentration ranged from 587.61 ppm to 1,360.05 ppm, and the similarity to the expected fluoride concentration ranged from 41.97% to 93.80%. Two samples were clearly separated when the samples were centrifuged, whereas the remaining four samples had unclear supernatants. The clearly separated toothpastes (i.e., toothpastes 5 and 6) had BF concentrations that were similar to or lower than the declared fluoride concentrations and the measured TF concentrations. However, the unclearly separated toothpastes showed inconsistent relationships between the measured TF and BF concentrations. CONCLUSIONS: The measured TF and BF concentrations of the six toothpastes did not reach the expected fluoride concentration. This finding resulted from the different compositions and forms of the toothpastes. Therefore, the properties of toothpastes need to be considered when measuring their fluoride concentrations.
Biological Availability* ; Fluorides* ; Hydrochloric Acid ; Hydrogen ; Ion-Selective Electrodes ; Ions ; Osmolar Concentration ; Product Packaging ; Toothpastes*

OBJECTIVES: The aim of this study was to evaluate the fluoride release of conventional glass ionomer cements (GICs) and resin-modified GICs. MATERIALS AND METHODS: The cements were grouped as follows: G1 (Vidrion R, SS White), G2 (Vitro Fil, DFL), G3 (Vitro Molar, DFL), G4 (Bioglass R, Biodinamica), and G5 (Ketac Fil, 3M ESPE), as conventional GICs, and G6 (Vitremer, 3M ESPE), G7 (Vitro Fil LC, DFL), and G8 (Resiglass, Biodinamica) as resin-modified GICs. Six specimens (8.60 mm in diameter; 1.65 mm in thickness) of each material were prepared using a stainless steel mold. The specimens were immersed in a demineralizing solution (pH 4.3) for 6 hr and a remineralizing solution (pH 7.0) for 18 hr a day. The fluoride ions were measured for 15 days. Analysis of variance (ANOVA) and Tukey's test with 5% significance were applied. RESULTS: The highest amounts of fluoride release were found during the first 24 hr for all cements, decreasing abruptly on day 2, and reaching gradually decreasing levels on day 7. Based on these results, the decreasing scale of fluoride release was as follows: G2 > G3 > G8 = G4 = G7 > G6 = G1 > G5 (p < 0.05). CONCLUSIONS: There were wide variations among the materials in terms of the cumulative amount of fluoride ion released, and the amount of fluoride release could not be attributed to the category of cement, that is, conventional GICs or resin-modified GICs.
Dental Materials ; Fluorides* ; Fungi ; Glass Ionomer Cements* ; Glass* ; Ions ; Molar ; Stainless Steel

Electrical rhythmicity in the gastrointestinal (GI) muscles is generated by pacemaker cells, known as interstitial cells of Cajal (ICC). In the present study, we investigated the effect of external divalent cations on pacemaking activity in cultured ICC from murine small intestine by using whole-cell patch clamp techniques. ICC generated pacemaker currents under a voltage clamp or electrical pacemaker potentials under a current clamp, and showed a mean amplitude of -500+/-50 pA or 30+/-1 mV and the frequency of 18+/-2 cycles/min. Treatments of the cells with external 0 mM Ca2+ stopped pacemaking activity of ICC. In the presence of 2 mM Ca2+, 0 mM external Mg2+ depolarized the resting membrane potential, and there was no change in the frequency of pacemaking activity. However, 10 mM external Mg2+ decreased the frequency of pacemaking activity (6.75+/-1 cycles/min, n=5). We replaced external 2 mM Ca2+ with equimolar Ba2+, Mn2+ and Sr2+, and they all developed inward current in the sequence of Ba2+> Mn2+> Sr2+. Also the frequency of the pacemaking activity was stopped or irregulated. We investigated the effect of 10 mM Ba2+, Mn2+ and Sr2+ on pacemaking activity of ICC in the presence of external 0 mM Mg2+, and found that 10 mM Ba2+ and Mn2+ induced large inward current and stopped the pacemaking activity of ICC (n=5). Interestingly, 10 mM Sr2+ induced small inward current and potentiated the amplitude of pacemaking activity of ICC (n=5). These results indicate that extracellular Ca2+ and Mg2+ are requisite for the pacemaking activity of ICC.
Cations, Divalent* ; Interstitial Cells of Cajal ; Intestine, Small ; Membrane Potentials ; Muscles ; Patch-Clamp Techniques ; Periodicity