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121.
122.
Naganuma T Tohno Y Yamasaki M Tohno S Azuma C Minami T Morikawa H 《Biological trace element research》2004,101(3):203-210
To elucidate compositional changes of the rami of the internal iliac artery with aging, the authors investigated age-related
changes of the calcium content in the uterine, internal pudendal, umbilical, and obturator arteries by inductively coupled
plasma-atomic emission spectrometry. After an ordinary dissection was finished, the uterine, internal pudendal, umbilical,
and obturator arteries were resected from 10 female subjects, and the internal pudendal, umbilical, and obturator arteries
were resected from 10 male subjects. The female subjects ranged in age from 52 to 96 yr, and the male subjects ranged in age
from 63 to 88 yr. The calcium content in the uterine artery began to increase in the seventies and increased markedly in the
nineties. In the internal pudendal artery, the calcium content hardly increased up to the eighties and increased significantly
in the nineties. In contrast, the calcium content did not change in both the umbilical and obturator arteries with advancing
age. It was found that the average content of calcium was the highest in the uterine artery and decreased in the order internal
pudendal, umbilical, and obturator arteries. The average content of calcium in the uterine arteries corresponded to 46-fold
the amount of the women's obturartor arteries, in which it was the lowest. In the cases of men, the average content of calcium
was higher in the order of the internal pudendal, umbilical, and obturator arteries. Regarding the average content of calcium,
the order internal pudendal, umbilical, and obturator arteries of the men was consistent with that of the women. 相似文献
123.
Mahakkanukrauh P Tohno S Tohno Y Chomsung R Azuma C Moriwake Y Minami T 《Biological trace element research》2004,100(3):205-214
To examine whether there were differences between races in regard to the relationships among element contents in the arteries,
the authors investigated the relationships among the average contents of calcium, phosphorus, sulfur, and magnesium in the
18 kinds of the Thai artery. After ordinary dissection by medical students at Chiang Mai University was finished, the thoracic
and abdominal aortas, ramifying site of the abdominal aorta into the common iliac arteries, coronary, common carotid, internal
thoracic, subclavian, axillary, brachial, radial, superior and inferior mesenteric, renal, common iliac, internal iliac, and
external iliac arteries were resected from the subjects who consisted of 12 men and 3 women, ranging in age from 39 to 84
yr. The femoral and posterior tibial arteries were resected from the subjects, consisting of 15 men and 5 women, ranging in
age from 25 to 88 yr. The element content of the arteries was analyzed by inductively coupled plasma-atomic emission spectrometry.
It was found that there were extremely significant direct correlations among the average contents of calcium, phosphorus,
and magnesium in the 18 kinds of the Thai artery, but no significant correlations were found between the average contents
of sulfur and elements, such as calcium, phosphorus, and magnesium. These results were in agreement with those of the Japanese
arteries. Therefore, it was suggested that there was no significant difference between the arteries of the Thai and the Japanese
in the relationships among calcium, phosphorus, sulfur, and magnesium. 相似文献
124.
Age-related changes of elements and relationships among elements in the common bile and pancreatic ducts 总被引:1,自引:0,他引:1
Tohno Y Tohno S Yamada MO Azuma C Moriwake Y Minami T Maruyama H Omura T 《Biological trace element research》2004,101(1):47-60
To elucidate compositional changes of the common bile and main pancreatic ducts with aging, the authors investigated age-related
changes of element contents in the common bile and pancreatic ducts by inductively coupled plasma-atomic emission spectrometry.
After ordinary dissection by medical students was finished, the common bile ducts and main pancreatic ducts (pancreatic ducts)
were resected and the element contents were determined. The Mg content increased significantly only in the pancreatic duct
with aging, but the other element contents did not change significantly in both the common bile and pancreatic ducts with
aging. Regarding the relationship among the elements, significant direct correlations were found among the contents of Ca,
P, S, and Mg in the common bile ducts, with some exceptions between P and either S or Mg contents. In the pancreatic ducts,
significant direct correlations were found between S and Mg contents and between P and Na contents. The relationships in the
elements between the common bile and pancreatic ducts were examined. It was found that there were significant direct correlations
in the Ca, Mg, and Fe contents between the common bile and pancreatic ducts; that is, as Ca, Mg, and Fe increased in the common
bile duct, they increased simultaneously in the pancreatic duct. 相似文献
125.
Tsukamoto H Hishinuma T Suzuki N Tayama R Hiratsuka M Yoshihisa T Mizugaki M Goto J 《Prostaglandins & other lipid mediators》2004,73(3-4):191-213
Thiazolidinedione, peroxisome proliferator-activated receptor gamma (PPARgamma) agonist, has been used as an anti-diabetic drug and as an useful tool to elucidate multiple PPARgamma functions by in vitro and in vivo studies. We investigated the effects of thiazolidinediones on prostanoid production in lipopolysaccharide-stimulated cells. The high concentrations (>10 microM) of rosiglitazone and pioglitazone significantly increased lipopolysaccharide-stimulated prostanoid production such as thromboxane A2 and prostaglandin E2. However, PPARgamma antagonist could not inhibit them. In PPARgamma-deficient cells, thiazolidinediones increased prostaglandin E2 production. Thiazolidinediones increased arachidonic acid (AA) release from the cell membrane by not stimulating AA releasing process involving several phospholipase A2s but inhibiting AA reuptaking process. The expression of cyclooxygenase-1 and cyclooxygenase-2 were not affected by thiazolidinediones. In this study, we demonstrated that high concentrations of TZDs increased AA release by the inhibition of AA reuptaking process, leading to subsequent increase in the prostanoid production in a PPARgamma-independent manner. This mechanism provides useful information for the elucidation of multiple PPARgamma functions and diabetic drug therapy. 相似文献
126.
Paik MJ Lee Y Goto J Kim KR 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2004,803(2):257-265
Profens were converted into diastereomeric (R)-(+)-1-phenylethylamides using ethyl chloroformate and triethylamine in dichloromethane. Gas chromatographic analysis on dual-columns with different polarities provided complete enantioresolution of eight profens, facilitating chiral discrimination based on matching with retention index sets characteristic of each enantiomer. The present method was linear (r >/= 0.9992) with good precision (0.8-6.0%) and accuracy (-9.3 to 0.003%), allowing detection of trace (R)-profens in optical purity test on four (S)-profen mixture in a single run. And the method allowed simultaneous enantiomeric screening for ibuprofen enantiomers and their chiral metabolites excreted in urine following administration of racemic ibuprofen. 相似文献
127.
Yada T Muto K Azuma T Ikuta K 《Comparative biochemistry and physiology. Toxicology & pharmacology : CBP》2004,139(1-3):57-63
In vivo and in vitro effects of prolactin (PRL) and growth hormone (GH) on plasma levels of lysozyme and ceruloplasmin were examined in the rainbow trout (Oncorhynchus mykiss). Hypophysectomy had no effect on the plasma lysozyme level. Implantation of PRL- or GH-containing cholesterol pellets increased the lysozyme level in a dose-related manner. After hypophysectomy and sham operation, plasma ceruloplasmin was elevated above the level in intact fish, suggesting inflammation caused by the surgery. PRL or GH treatment significantly attenuated the increased level of ceruloplasmin in the operated fish. Expression of lysozyme mRNA was detected in the leucocytes isolated from the peripheral blood by RT-PCR. In vitro administration of PRL or GH showed no effect on the proliferation of isolated leucocytes or on the total protein content; however, lysozyme activity in the medium increased in a dose-related manner. These results suggest that PRL and GH directly stimulate lysozyme production without affecting the proliferation of leucocytes, and the attenuated ceruloplasmin level increased in response to inflammation. 相似文献
128.
Niiro H Azuma H Tanago S Matsumura K Shikata K Tachibana T Ogino K 《Bioorganic & medicinal chemistry》2004,12(1):45-51
(2R,3Z)-, (2R,3E)-, (2S,3Z) and (2S,3E)-2-Acetylamino-3-octadecen-1-ol, and (2R)- and (2S)-2-acetylamino-octadecan-1-ol were prepared using the Wittig olefination of Garner's aldehyde (N-Boc-N,O-isopropylidene-L- or D-serinal) from L- or D-serine. The apoptotic activities of these saturated and unsaturated 2-acetylaminoalcohols were examined in human leukemia HL-60 cells using MTT assay. Among the newly synthesized compounds, the cis-isomers were the most potent. Despite their simple structures, (2R,3Z)- and (2S,3Z)-2-acetylamino-3-octadecen-1-ol showed high and comparable apoptotic activities compared with N-acetyl-D-erythro-sphingosine (D-e-C2-Cer, a well-known inducer of apoptosis). Their apoptotic activities were in the order D-e-C2-Cer approximately L-e-C2-Cer approximately (2R,3Z)- approximately (2S,3Z)->(2R,3E)- approximately (2S,3E)- approximately (2R)- approximately (2S)-derivative. Qualitative analysis of DNA fragmentation caused by these compounds was conducted using agarose gel electrophoresis, and typical DNA fragmentation was found in the cases of (2R,3Z)- and (2S,3Z)-isomers such as C2-Cer, but not trans and saturated isomers. The morphological features of the cells, the proteolytic processing of pro-caspase-3, and the cleavage of PARP as a result of exogenous treatment with (2R,3Z)- and (2S,3Z)-isomers indicated that cell death induced by these compounds was apoptosis. These observations suggest that these newly synthesized compounds, (3Z)-2-Acetylamino-3-octadecen-1-ol, have similar characteristics and apoptosis-inducing activities against HL-60 cells with C2-Cer. 相似文献
129.
Nitric oxide inhibits ultraviolet B-induced murine keratinocyte apoptosis by regulating apoptotic signaling cascades 总被引:2,自引:0,他引:2
Cytotoxic effects of nitric oxide (NO) derived from inducible nitric oxide synthase (iNOS) are considered to be one of the major causes of inflammatory diseases. On the other hand, protective effects of NO on toxic insults-induced cellular damage/apoptosis have been demonstrated recently. Ultraviolet B (UVB)-induced apoptosis of epidermal keratinocytes leads to skin inflammation and photoageing. However, it has not been elucidated what kind of effects NO has on UVB-induced keratinocyte apoptosis. Thus, in the present study, we investigated the problem and demonstrated that NO from NO donor suppressed UVB-induced apoptosis of murine keratinocytes. In addition, NO significantly suppressed activities of caspase 3, caspase 8 and caspase 9 that had been upregulated by UVB radiation. NO also suppressed p53 expression that had been upregulated by UVB radiation and upregulated Bcl-2 expression that had been downregulated by UVB radiation. These findings suggested that NO might suppress UVB-induced keratinocyte apoptosis by regulating apoptotic signaling cascades in p53, Bcl-2, caspase3, caspase 8 and caspase 9. 相似文献
130.
Grishko V Pastukh V Solodushko V Gillespie M Azuma J Schaffer S 《American journal of physiology. Heart and circulatory physiology》2003,285(6):H2364-H2372
Angiotensin II contributes to ventricular remodeling by promoting both cardiac hypertrophy and apoptosis; however, the mechanism underlying the latter phenomenon is poorly understood. One possibility that has been advanced is that angiotensin II activates NADPH oxidase, generating free radicals that trigger apoptosis. In apparent support of this notion, it was found that angiotensin II-mediated apoptosis in the cardiomyocyte is blocked by the NADPH oxidase inhibitor diphenylene iodonium. However, three lines of evidence suggest that peroxynitrite, rather than superoxide, is responsible for angiotensin II-mediated DNA damage and apoptosis. First, the inducible nitric oxide inhibitor aminoguanidine prevents angiotensin II-induced DNA damage and apoptosis. Second, based on ligation-mediated PCR, the pattern of angiotensin II-induced DNA damage resembles peroxynitritemediated damage rather than damage caused by either superoxide or nitric oxide. Third, angiotensin II activates p53 through the phosphorylation of Ser15 and Ser20, residues that are commonly phosphorylated in response to DNA damage. It is proposed that angiotensin II promotes the oxidation of DNA, which in turn activates p53 to mediate apoptosis. 相似文献