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1.
Scand J Med Sci Sports ; 26(11): 1353-1359, 2016 Nov.
Article in English | MEDLINE | ID: mdl-26589580

ABSTRACT

The International Paralympic Committee has a maximum allowable standing height (MASH) rule that limits stature to a pre-trauma estimation. The MASH rule reduces the probability that bilateral lower limb amputees use disproportionately long prostheses in competition. Although there are several methods for estimating stature, the validity of these methods has not been compared. To identify the most appropriate method for the MASH rule, this study aimed to compare the criterion validity of estimations resulting from the current method, the Contini method, and four Canda methods (Canda-1, Canda-2, Canda-3, and Canda-4). Stature, ulna length, demispan, sitting height, thigh length, upper arm length, and forearm length measurements in 31 males and 30 females were used to calculate the respective estimation for each method. Results showed that Canda-1 (based on four anthropometric variables) produced the smallest error and best fitted the data in males and females. The current method was associated with the largest error of those tests because it increasingly overestimated height in people with smaller stature. The results suggest that the set of Canda equations provide a more valid MASH estimation in people with a range of upper limb and bilateral lower limb amputations compared with the current method.


Subject(s)
Amputees , Anthropometry/methods , Body Height , Sports for Persons with Disabilities/standards , Arm/anatomy & histology , Asian People , Australia , Female , Forearm/anatomy & histology , Humans , Japan , Male , Posture , Thigh/anatomy & histology , Ulna/anatomy & histology , White People
2.
Environ Sci Technol ; 35(1): 114-20, 2001 Jan 01.
Article in English | MEDLINE | ID: mdl-11351993

ABSTRACT

Chlorine atom-initiated photooxidations of three homologous methyl perfluoroalkyl ethers (HFEs), n-C(n)F(2n+1)OCH3 (n = 2, 3, and 5), in air in the absence of NOx were investigated with a long path FTIR/photochemical reaction system to elucidate the degradation mechanisms. The environmental removal processes of these three ethers in the troposphere were estimated. For oxidation of the three ethers, perfluoroalkyl formates (C(n)F(2n+1)OCHO; n = 2, 3 and 5) as relatively stable intermediates were produced at unity of the production ratio, which was independent of the perfluoroalkyl length. The rate constants for the reaction of Cl atoms with C2F5OCHO, C3F7OCHO, and C5F11OCHO were (1.2 +/- 0.5) x 10(-14), (1.2 +/- 0.5) x 10(-14), and (1.8 +/- 0.7) x 10(-14) cm3 molecule(-1) s(-1), respectively. The rate constants of the reaction of Cl with produced perfluoroalkyl formates were larger than these of perfluoroalkyl ethers. The formyl group of the perfluoroalkyl formates was finally converted to carbon dioxide. The -CF2- of the perfluoroalkyl groups for the three ethers was mainly converted to COF2 through the C-C cleavage; the conversion ratios from the carbons of the perfluoroalkyl group to COF2 were 48 +/- 10, 76 +/- 10, and 60 +/- 10% for C2F5OCH3, n-C3F7OCH3, and n-C5F11OCH3, respectively. Sixteen percent of the perfluoroalkyl group for n-C3F7OCH3 was converted to C2F5COF. Similarly, the perfluoroalkyl group of n-C5F11OCH3 was converted to C(n)F(2n+1)COF (n = 2, 3, and/or 4) with the yield of 15-30%, while for C2F5OCH3, the formation of CF3COF was not confirmed. As an oxidation product of the terminal CF3- group, 20, 22, and 16% of the CF3 group for C2F5OCH3, n-C3F7OCH3, and n-C5F11OCH3, respectively, were converted to CF3OOOCF3.


Subject(s)
Chlorine/chemistry , Ethers/chemistry , Biodegradation, Environmental , Environmental Pollutants/analysis , Magnetic Resonance Spectroscopy , Oxidation-Reduction , Photochemistry , Spectroscopy, Fourier Transform Infrared
3.
Environ Sci Technol ; 35(9): 1880-4, 2001 May 01.
Article in English | MEDLINE | ID: mdl-11355208

ABSTRACT

Photocatalytic oxidation of benzene in gas phase was carried out with a flow reactor at room temperature. In a humidified airstream ([H2O] = 2.2%), benzene was quantitatively decomposed to CO2 over UV-irradiated 1.0 wt %-Pt/TiO2 catalyst. When the benzene conversion was decreased, the selectivity to CO2 was decreased, while that to CO was increased. As the amount of Pt loaded on the TiO2 catalyst was increased, the rate of the CO photooxidation was increased, while that of benzene photooxidation was almost unchanged. These findings showed that the photooxidation of benzene to CO2 over Pt/TiO2 catalyst proceeded by the two sequential steps: (i) benzene was decomposed to CO2 and CO with the selectivities of 94% and 6%, respectively, and (ii) CO was subsequently oxidized to CO2. The rate of CO photooxidation over Pt/TiO2 catalyst was greatly decreased by the presence of benzene in the reaction gas stream. The complete oxidation of benzene to CO2 could be also achieved by using the hybrid catalysts comprising pure TiO2 and platinized TiO2.


Subject(s)
Benzene/chemistry , Catalysis , Gases , Humidity , Oxidation-Reduction , Photochemistry , Platinum , Titanium
4.
Eur J Pharmacol ; 411(1-2): 27-34, 2001 Jan 05.
Article in English | MEDLINE | ID: mdl-11137855

ABSTRACT

To examine whether angiotensin II and endothelins produced in vascular smooth muscle cells can play roles in the regulation of mitogen-activated protein (MAP) kinase activity in vascular smooth muscle cells, we measured the activity of MAP kinases in cultured vascular smooth muscle cells, and determined effects of renin-angiotensin and endothelin systems activators and inhibitors. Angiotensin II and endothelin-1 produced an activation of MAP kinase activity in vascular smooth muscle cells, whereas the angiotensin receptor antagonist, losartan and the endothelin receptor antagonist, cyclo (D-alpha-aspartyl-L-prolyl-D-valyl-L-leucyl-D-tryptophyl, BQ123) inhibited the enzyme activity. MAP kinase activity in vascular smooth muscle cells was also inhibited either by the renin inhibitor pepstatin A or by the angiotensin-converting enzyme inhibitor captopril. The degree of the inhibition of MAP kinase activity by pepstatin A, captopril and losartan was almost the same. Renin produced a considerable increase in MAP kinase activity and the renin-induced MAP kinase activation was inhibited by pepstatin A. The endothelin precursor big endothelin-1 produced an increase of MAP kinase activity in vascular smooth muscle cells, whereas the endothelin-converting enzyme inhibitor phosphoramidon inhibited the enzyme activity. These findings suggest that functional renin-angiotensin system and endothelin system are present in vascular smooth muscle cells and these systems tonically serve to increase MAP kinase activity. It appears that renin or renin-like substances play the determining role in the regulation of renin-angiotensin system in vascular smooth muscle cells.


Subject(s)
Angiotensin II/physiology , Endothelins/physiology , Mitogen-Activated Protein Kinases/metabolism , Muscle, Smooth, Vascular/metabolism , Angiotensin I/pharmacology , Angiotensin II/pharmacology , Angiotensin-Converting Enzyme Inhibitors/pharmacology , Animals , Captopril/pharmacology , Cells, Cultured , Dose-Response Relationship, Drug , Endothelin Receptor Antagonists , Endothelin-1/pharmacology , Endothelins/pharmacology , Glycopeptides/pharmacology , Losartan/pharmacology , Male , Muscle, Smooth, Vascular/cytology , Muscle, Smooth, Vascular/drug effects , Pepstatins/pharmacology , Peptides, Cyclic/pharmacology , Protease Inhibitors/pharmacology , Protein Precursors/pharmacology , Rats , Rats, Wistar , Renin/pharmacology
5.
Eur J Pharmacol ; 400(2-3): 231-7, 2000 Jul 21.
Article in English | MEDLINE | ID: mdl-10988339

ABSTRACT

Regulation mechanisms of the activity of vascular mitogen-activated protein (MAP) kinases, enzymes believed to be involved in the pathway for cell proliferation, may be altered in hypertension. To examine whether vascular MAP kinase activation mechanisms are altered in hypertension, we measured the activity of MAP kinases in rat aorta strips from spontaneously hypertensive rats (SHR) and from deoxycorticosterone acetate (DOCA)-salt hypertensive rats, and examined whether vascular angiotensin and endothelin systems are responsible for the alteration of MAP kinase activation in these hypertensive models. Endothelium-denuded aorta strips were incubated at 37 degrees C in medium. MAP kinase activity after incubation was increased in rat aorta strips. The MAP kinase activation was greater in 9- and 15-week-old SHR aorta strips than in age-matched Wistar Kyoto rats (WKY) aorta strips. Similarly, MAP kinase activation was enhanced in aorta strips from DOCA-salt hypertensive rats. In aorta strips from these kinds of rats, the angiotensin receptor antagonist, losartan, and the endothelin receptor antagonist, cyclo (D-alpha-aspartyl-L-prolyl-D-valyl-L-leucyl-D-tryptophyl) (BQ123), inhibited the MAP kinase activation. The losartan-induced, but not BQ123-induced, inhibition of MAP kinase activation was enhanced in 15-week-old SHR aorta strips, whereas the BQ123-induced, but not losartan-induced, inhibition of MAP kinase activation was enhanced in DOCA-salt hypertensive rat aorta strips. Angiotensin II-induced MAP kinase activation was enhanced in 15-week-old SHR aorta strips, whereas it was depressed in DOCA-salt hypertensive rat aorta strips. These results indicate that MAP kinase activation function is enhanced in aorta strips from both kinds of hypertensive rats. It appears that the enhancement of MAP kinase activation results partly from enhanced vascular angiotensin system in SHR and from enhanced vascular endothelin system in DOCA-salt hypertensive rats.


Subject(s)
Hypertension/enzymology , Mitogen-Activated Protein Kinases/metabolism , Muscle, Smooth, Vascular/enzymology , Angiotensin II/pharmacology , Angiotensin Receptor Antagonists , Animals , Antihypertensive Agents/pharmacology , Desoxycorticosterone , Endothelin Receptor Antagonists , Endothelin-1/pharmacology , Endothelium, Vascular/physiology , Enzyme Activation , Hypertension/chemically induced , Hypertension/genetics , In Vitro Techniques , Losartan/pharmacology , Male , Mitogen-Activated Protein Kinases/antagonists & inhibitors , Peptides, Cyclic/pharmacology , Rats , Rats, Inbred SHR , Rats, Inbred WKY , Rats, Wistar , Receptor, Angiotensin, Type 1 , Receptor, Angiotensin, Type 2 , Receptors, Angiotensin/physiology , Receptors, Endothelin/physiology , Sodium Chloride , Vasoconstrictor Agents/pharmacology
6.
Eur J Pharmacol ; 372(3): 279-85, 1999 May 21.
Article in English | MEDLINE | ID: mdl-10395023

ABSTRACT

The vascular structural remodeling function may be altered in genetically hypertensive animals, spontaneously hypertensive rats (SHR). To examine this possibility, we measured the activity of mitogen-activated protein (MAP) kinases, enzymes believed to be involved in the pathway for cell proliferation, in rat aorta strips, and examined whether the endothelium removal-induced MAP kinase activation function is altered in SHR and whether vascular angiotensin and endothelin systems are responsible for the alteration of MAP kinase activation in SHR. Male 4-week-old SHR and age-matched Wistar Kyoto rats (WKY) supplied by Charles River Japan were used. Endothelium-denuded aorta strips were incubated at 37 degrees C in medium. MAP kinase activity after incubation was time-dependently increased in strips from SHR and WKY. MAP kinase activation was greater in SHR than in WKY aorta strips. Similarly, MAP kinase activation was enhanced in aorta strips from 4-week-old SHR and stroke prone SHR supplied by the Diseases Model Cooperative Research Association (Kyoto, Japan). In aorta strips from SHR and WKY, the angiotensin receptor antagonist, losartan, and the endothelin receptor antagonist, cyclo (D-alpha-aspartyl-L-prolyl-D-valyl-L-leucyl-D-tryptophyl)(BQ123), caused concentration-dependent inhibition of MAP kinase activation. The losartan-induced but not BQ123-induced inhibition of MAP kinase activation was greater in SHR than in WKY aorta strips. Angiotensin II caused a concentration-dependent increase in MAP kinase activity and the angiotensin II-induced MAP kinase activation was greater in SHR than in WKY aorta strips. These results indicate that endothelium removal-induced MAP kinase activation is enhanced in aorta strips from young SHR, suggesting that vascular structural remodeling function may be enhanced in SHR. It appears that the enhancement of MAP kinase activation results, at least in part, from enhanced function of vascular angiotensin system in SHR.


Subject(s)
Angiotensin II/pharmacology , Calcium-Calmodulin-Dependent Protein Kinases/metabolism , Endothelium, Vascular/enzymology , Hypertension/enzymology , Animals , Antihypertensive Agents/pharmacology , Aorta , Calcium-Calmodulin-Dependent Protein Kinases/drug effects , Endothelin-1/pharmacology , Enzyme Activation/drug effects , Hypertension/metabolism , Losartan/pharmacology , Male , Peptides, Cyclic/pharmacology , Rats , Rats, Inbred SHR , Rats, Inbred WKY
7.
Eur J Pharmacol ; 365(1): 103-10, 1999 Jan 15.
Article in English | MEDLINE | ID: mdl-9988128

ABSTRACT

We previously reported that endogenous angiotensin II is released to cause mitogen-activated protein (MAP) kinase stimulation in the media portion of the vasculature. In this study, we examined whether a functional renin-angiotensin system is indeed present within the media of the vasculature. In rat aortic strips, endothelium removal produced an increase of MAP kinase activity. The MAP kinase activation was inhibited either by the renin inhibitor pepstatin A or by the angiotensin-converting enzyme inhibitor captopril. The degree of the inhibition of the MAP kinase activation by pepstatin A, captopril and the angiotensin receptor antagonist losartan was almost the same. Pepstatin A inhibited MAP kinase activation induced by renin but not by angiotensin I and angiotensin II. Captopril inhibited the MAP kinase activation induced by angiotensin I but not by angiotensin II. In nephrectomized rat aortic strips, endothelium removal also produced an increase in MAP kinase activity, but the MAP kinase activation was considerably small and minimally inhibited by losartan. Nephrectomy produced a marked decrease in plasma renin activity. These findings suggest that an apparently fully intact and functional renin-angiotensin system is present in the media of the rat vasculature and this system serves to increase MAP kinase activity. It appears that renin plays the determining role in the regulation of angiotensin generation also in the media and the major source of the renin is renin of kidney origin.


Subject(s)
Aorta/enzymology , Calcium-Calmodulin-Dependent Protein Kinases/metabolism , Renin-Angiotensin System/physiology , Angiotensin I/pharmacology , Angiotensin II/pharmacology , Angiotensin-Converting Enzyme Inhibitors/pharmacology , Animals , Calcium-Calmodulin-Dependent Protein Kinases/drug effects , Captopril/pharmacology , Endothelium, Vascular/physiology , Enzyme Activation/drug effects , In Vitro Techniques , Male , Nephrectomy , Pepstatins/pharmacology , Protease Inhibitors/pharmacology , Rats , Rats, Wistar , Renin/pharmacology , Vasoconstrictor Agents/pharmacology
8.
Anal Chem ; 61(6): 619-23, 1989 Mar 15.
Article in English | MEDLINE | ID: mdl-2729594

ABSTRACT

Indigo-5,5'-disulfonate (IDS) was found to be an efficient reagent for the determination of ozone by chemiluminescence (CL); hence it was applied to the continuous measurements of dissolved ozone (O3(aq]. The optimum reagent composition was determined as 10 mg L-1 IDS plus 2 mM phosphate (pH 7.2). The CL intensity was proportional to the O3(aq) concentration in the range of 0.025-410 ng mL-1. The detection limit was 0.006 ng mL-1, which is 3 orders of magnitude lower than that obtained by spectrophotometry using IDS as reported previously. The reduction of interferences from aldehydes and hydrogen peroxide was attempted. Furthermore, the mechanism of the CL was discussed from CL and fluorescence spectra measured.


Subject(s)
Ozone/analysis , Chemical Phenomena , Chemistry , Fluorescence , Hydrogen-Ion Concentration , Indicators and Reagents , Indigo Carmine , Luminescent Measurements
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