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21.
22.
Physical effects of negative air ions in a wet sauna 总被引:10,自引:0,他引:10
I. Watanabe Hiroshi Noro Yoshinori Ohtsuka Yukio Mano Yuko Agishi 《International journal of biometeorology》1997,40(2):107-112
The physical effects of negative air ions on humans were determined in an experimental sauna room equipped with an ionizer.
Thirteen healthy persons took a wet sauna bath (dry bulb temperature 42° C, relative humidity 100%, 10 min exposure) with
or without negative air ions. The subjects were not told when they were being exposed to negative air ions. There were no
differences in the moods of these persons or changes in their blood pressures between the two saunas. The surface temperatures
of the foreheads, hands, and legs in the sauna with negative ions were significantly higher than those in the sauna without
ions. The pulse rates and sweat produced in the sauna with ions were singificantly higher than those in the sauna without
ions. The results suggest that negative ions may amplify the effects on humans of the sauna.
Received: 31 March 1995 / Revised: 25 July 1995 / Accepted: 26 July 1996 相似文献
23.
Peptides inhibit selectin-mediated cell adhesion in vitro, and neutrophil influx into inflammatory sites in vivo 总被引:1,自引:0,他引:1
Briggs John B.; Oda Yuko; Gilbert James H.; Schaefer Mary E.; Macher Bruce A. 《Glycobiology》1995,5(6):583-588
The selectins are cell adhesion molecules whose carbohydrate-bindingdomain (C-type lectin) is thought to be involved in leukocyteadhesion to activated vascular endothelium in the inflammatoryprocess. A series of peptides, based on a conserved region (48YYWIGIRK55-NH2)of the lectin domain of E-, L- and P-selectins, were analysedfor their ability to block selectin-mediated cell adhesion invitro, and neutrophil infiltration into sites of inflammationin vivo. The peptides inhibited the adhesion of myeloid cellsto recombinant forms of E- and P-selectin. The adhesion of myeloidcells to human endothelial cells, stimulated to express E-selectin,was also inhibited by the peptides. Finally, the peptides blockedthe adhesion of lymphocytes, expressing L-selectin, to highendothelial venules in lymph nodes which contain the ligandfor L-selectin. A clear structure-activity relationship wasestablished when peptides of different amino acid chain lengthswere tested in these assays. Peptides lacking tyrosine residues(e.g. WIGIR-NH2) at their amino terminus were poor inhibitorsof selectin-mediated cell adhesion in vitro. The peptides thatwere found to be inhibitors of cell adhesion in vitro were alsofound to inhibit (up to 70%) neutrophil infiltration into sitesof inflammation in a thioglycollate-induced peritonitis mousemodel system. They also significantly reduced (>50%) themigration of neutrophils into cytokine-treated skin. These resultsstrongly suggest that compounds based on these tyrosine-containing,selectin-derived peptides could be used as anti-inflammatorytherapeutic agents. inflammation neutrophils peptides selectins 相似文献
24.
25.
Calpain and calpastatin in porcine retina. Identification and action on microtubule-associated proteins. 总被引:2,自引:0,他引:2 下载免费PDF全文
Two forms of Ca2+-dependent cysteine proteinase (calpain, EC 3.4.22.17) and their specific endogenous inhibitor (calpastatin) were partially purified from porcine retina: calpain I (low-Ca2+-requiring form) was half-maximally activated at 8 microM-Ca2+, and calpain II (high-Ca2+-requiring form) at 250 microM-Ca2+. Both calpain I and calpain II were inhibited by calpastatin. Calpain I from porcine retina was shown to be composed of 83 000- and 29 000-Mr subunits, and calpain II of 80 000- and 29 000-Mr subunits, by the use of monospecific antibodies. Calpains I and II were both found to hydrolyse microtubule-associated proteins 1 and 2 rapidly. 相似文献
26.
Solvolysis of chondroitin 4- or 6-sulfate (pyridinium salt) with dimethyl sulfoxide containing 10% of methanol for 18 h at 95° resulted in the cleavage of the 2-amino-2-deoxy-D-glucoside bonds together with initial desulfation to give methyl β-glycosides of N-acetylchondrosine as a main product and, in addition, higher oligosaccharides, without any loss of uronic acid. Dermatan sulfate was also depolymerized to yield methyl glycosides of di- and higher oligosaccharides under the same conditions. Hyaluronic acid (free acid) was depolymerized by the same solvent in the presence of an equimolar amount of pyridine-sulfur trioxide or pyridinium sulfate per disaccharide unit to give methyl glycosides of di- and higher oligosaccharides. In contrast N-desulfated, N-acetylated heparin was stable under these solvolytic conditions and did not yield heparin oligosaccharides. 相似文献
27.
28.
When cultured porcine aortic endothelial cells (ECs) were incubated with porcine big endothelin-1 (bit ET-1(1-39)), there was a time-dependent increase in immunoreactive (IR)-ET in the culture supernatant, in addition to an endogenous IR-ET release fron the cells. Reverse-phase HPLC of the culture supernatant revealed one major IR-ET component corresponding to the elution position of synthetic ET-1, thereby indicating that the additional increase in IR-ET was due to the conversion of big ET-1 to mature ET-1(1-21). Phosphoramidon, a metalloproteinase inhibitor, strongly suppressed this increase in IR-ET as well as the endogenous IR-ET release. Cultured vascular smooth muscle cells (VSMCs) also released IR-ET. The apparent conversion of exogenously applied big ET-1 to ET-1 and its inhibition by phosphoramidon were observed using cultured VSMCs, although the enzyme inhibitor did not influence the basal secretion of IR-ET from VSMCs. These results suggest that both cultured ECs and VSMCs can generate ET-1 from exogenously applied big ET-1 via action of the same type of phosphoramidon-sensitive metalloproteinase, which is also involved in the endogenous ET-1 generation in ECs. 相似文献
29.
Nobuyuki Kato Makoto Hijikata Mosanori Nakagawa Yuko Ootsuyama Kanae Muraiso Showgo Ohkoshi Kunitada Shimotohno 《FEBS letters》1991,280(2):325-328
The amino acid sequence of the polyprotein deduced from the nucleotide sequence of the Japanese hepatitis C virus genome (N. Kato et. al. (1990) Proc. Natl. Acad. Sci. USA 87, 9524–9528)indicated that this virus is a member of a new class of positive-stranded RNA viruses. Several domains of this polyprotein also showed weak homology with those of flaviviruses and pestiviruses including the chymotrypsin-like serine proteinase. NTPase and RNA-dependent RNA polymerase 相似文献
30.
Mechanisms of somatic embryogenesis in cell cultures: Physiology,biochemistry, and molecular biology
A. Komamine R. Kawahara M. Matsumoto S. Sunabori T. Toya A. Fujiwara M. Tsukahara J. Smith M. Ito H. Fukuda K. Nomura T. Fujimura 《In vitro cellular & developmental biology. Plant》1992,28(1):11-14
Summary One of the most characteristic cell functions in plants is totipotency. Somatic embryogenesis can be regarded as a model system
for the investigation of mechanisms of totipotency, because a high frequency and synchronous embryogenic system from single
somatic cells has been established in carrot suspension cultures. Four phases are recognized in this process, and several
molecular markers, viz. polypeptides, mRNAs, antigens against monoclonal antibodies, can be detected during the expression
of totipotency, but they disappear during its loss. Four organ-specific genes have been isolated from hypocotyls and roots
by differential screening. They were expressed preferentially after the globular-heart stages of embryogenesis, and were strongly
suppressed by auxin. A CEM 1 gene was isolated by differential screening of embryogenic cell clusters. This gene was expressed
strongly and transiently during the proglobular and globular stages. The sequence of CEM 1 was found to encode a polypeptide
showing high homology to the elongation factor isolated from eucaryotic cells. Thus good progress is being made in understanding
the basic mechanisms of somatic embryogenesis.
Presented in the Session-in-Depth Developmental Biology of Embryogenesis at the 1991 World Congress on Cell and Tissue Culture,
Anaheim, California, June 16–20, 1991. 相似文献