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81.
Birgitta Fogelmark Hajime Goto Kazumi Yuasa Brigitte Marchat Ragnar Rylander 《Inflammation research》1992,35(1-2):50-56
The number of inflammatory cells was studied in lung walls and airways after inhalation of endotoxin or -1,3-glucan. In the water unsoluble form, -1,3-glucan caused a delayed response in terms of a decrease in macrophages and lymphocytes in the lung wall, 1 to 7 days after exposure but no invasion of neutrophils into the airways. When solubilized in 0.02 N NaOH, the cell response was the same as that observed after exposure to endotoxin. 相似文献
82.
Masanori Hosokawa Ryuichi Kasai Keiichi Higuchi Shuji Takeshita Katsuji Shimizu Hajime Hamamoto Atsuko Honma Mika Irino Kayoko Toda Atsuko Matsumura Mutsumi Matsushita Toshio Takeda 《Mechanisms of ageing and development》1984,26(1):91-102
For evaluation of the degree of senescence in SAM-P, accelerated senescence prone mouse, formerly called SAM or prone series or P-series, consisting of SAM-P/1, SAM-P/2, SAM-P/3 and SAM-P/4 corresponding to P-1, P-2, P-3 and P-4 series, respectively, in the previous reports, and in SAM-R, accelerated senescence resistant mouse, formerly called resistant series or R-series, consisting of SAM-R/1, SAM-R/2 and SAM-R/3 corresponding to R-1, R-2 and R-3 series, respectively, in the previous reports, the grading score system was adopted. The items to be examined in this system include 11 categories selected from the clinical signs and gross lesions considered to be associated with the aging process. The degree of the senescence in each category was graded from 0 to 4 according to the detailed criteria devised in our laboratory. After 8 months of age each mouse was examined every 4 months, and some of the mice were examined after 2 months of age.In almost all categories, the grading score and incidence began to increase from 4 or 6 months of age and continued to increase with advancing age in both SAM-P and SAM-R. The increase, however, was more marked in SAM-P than in SAM-R. The slow but steady increase in the SAM-R levelled out at 24 months of age and was comparable to that of 12 months of age in SAM-P. In both SAM-P/1 at 8 months of age and SAM-R/2 at 12 months of age, there was a significant reverse correlation between total score of this grading score system and length of residual life after examination.Systematic and extensive studies using the grading score system showed that if the validity of the system is, based on “irreversibility” and “universality” of the changes in 相似文献
83.
Orita S Hirose M Takahashi S Imaida K Ito N Shudo K Ohigashi H Murakami A Shirai T 《Toxicologic pathology》2004,32(2):250-257
Effects of dietary administration of 1'-acetoxychavicol acetate (ACA) and the novel synthetic retinoids 4-[1-hydroxy-3-oxo-3-(5,6,7,8-tetrahydro-3-hydroxy-5,5,8,8-tetramethyl-2-naphthalenyl)-1-propenyl]benzoic acid (Re-80); 4-[(5,6,7,8-tetrahydro-5,5,8,8-tetramethyl-2-naphthalenyl)carboxamido]benzoic acid (Am-580); and 6-[(3,5-di-tert-butylphenyl) carbamoyl]nicotinic acid (Am-55P) were examined using a two-stage rat carcinogenesis model. A total of 190 female SD rats was treated sequentially with 1,2-dimethylhydrazine (DMH, s.c.); 7,12-dimethylbenz(a)anthracene (DMBA, i.g.); and 2,2'-dihydroxy-di-n-propylnitrosamine (DHPN, in the drinking water) during the first three weeks (DDD-initiation), and an additional 60 rats received the vehicle alone (non-initiation). One week after the completion of the initiation period, they were divided into nine groups and administrated Re-80 (at dose levels of 1.0 or 0.4 ppm), Am-580 (20 or 4 ppm), Am-55P (20 ppm), ACA (100 ppm), all-trans-retinoic acid (10 or 2 ppm) or no supplement in the diet for 33 weeks, until survivors were euthanatized at week 37 weeks. After DDD-initiation, all-trans-retinoic acid at the high dose delayed the development of mammary tumors. The multiplicity of colon tumors in the group fed Am-55P and the incidences of nephroblastomas with ACA or Am-580 were decreased as compared with the control values, but the other chemicals had no modifying effects on tumor development in any organs. Thus, among ACA and the novel synthetic retinoids tested, only Am-55P showed a weak inhibitory effect on a neoplasm of general interest under the present experimental conditions. 相似文献
84.
Viability and osteogenic potential of cryopreserved human bone marrow-derived mesenchymal cells 总被引:18,自引:0,他引:18
Kotobuki N Hirose M Machida H Katou Y Muraki K Takakura Y Ohgushi H 《Tissue engineering》2005,11(5-6):663-673
Human bone marrow-derived mesenchymal cells contain mesenchymal stem cells (MSCs), which are well known for their osteo/chondrogenic potential and can be used for bone reconstruction. This article reports the viability of cryopreserved human mesenchymal cells and a comparison of the osteogenic potential between noncryopreserved and cryopreserved human mesenchymal cells with MSC-like characteristics, derived from the bone marrow of 28 subjects. The viability of cryopreserved mesenchymal cells was approximately 90% regardless of the storage term (0.3 to 37 months). It is clear by fluorescence-activated cell sorter analysis that the cell surface antigens of both noncryopreserved and cryopreserved mesenchymal cells were negative for hematopoietic cell markers such as CD14, CD34, CD45, and HLA-DR but positive for mesenchymal characteristics such as CD29 and CD105. To monitor the osteogenic potential of the cells, such as alkaline phosphatase (ALP) activity and in vitro mineralization, a subculture was conducted in the presence of dexamethasone, ascorbic acid, and glycerophosphate. No difference in osteogenic potential was found between cells with or without cryopreservation treatment. In addition, cells undergoing long-term cryopreservation (about 3 years) maintained high osteogenic potential. In conclusion, cryopreserved as well as noncryopreserved human mesenchymal cells could be applied for bone regeneration in orthopedics. 相似文献
85.
Omasu F Ezura Y Kajita M Ishida R Kodaira M Yoshida H Suzuki T Hosoi T Inoue S Shiraki M Orimo H Emi M 《Journal of human genetics》2003,48(7):342-345
Twin and family studies had shown that genetic factors are important determinants of bone mass. Multiple genes might be involved.
One candidate gene, the reversion-induced LIM gene (RIL), is a PDZ and LIM-domain-containing protein and has been localized within the cytokine cluster of chromosome 5 (5q31.1).
In a genetic study of 370 adult Japanese women, we investigated the correlation between radial bone mineral density (BMD)
and a genetic variation (−3333T→C) of the 5'-flanking region of RIL gene. A significant association was identified between the RIL variation −3333T→C and radial BMD (r=0.15, P=0.003). The variation of the RIL locus may be an important determinant of osteoporosis. 相似文献
86.
Kotoh K Nakamuta M Kohjima M Fukushima M Morizono S Kobayashi N Enjoji M Nawata H 《International journal of molecular medicine》2004,14(6):1049-1053
Liver cirrhosis is caused by a relative imbalance between synthesis and degradation of collagens. Arg-Gly-Asp (RGD) peptide is a major adhesive domain of several extracellular matrix (ECM) components, such as that involved in the binding of fibronectin to the alpha5beta1 integrin receptor. We previously reported that RGD peptide increased the expression of matrix metalloproteinase in hepatic stellate cells (HSCs) which play a major role in hepatic fibrosis. We evaluated whether RGD-peptides inhibit the progression of liver fibrosis in an animal model of carbon tetrachloride-induced hepatotoxicity. RGD peptide (GRGDS) (1 mg/kg body weight) was injected intraperitoneally (i.p.) 3 times a week for one month. The group treated with control peptide (GRGES) showed pathologically typical hepatic fibrosis, while the RGD-treated group showed minimal fibrotic changes. The liver contents of collagen and hydroxyproline in the RGD-treated group was significantly lower than that of the control group. Collagenase activity measured in liver homogenates was significantly higher in the treated group than in the control group. In an in vitro study using TWNT-4 cells derived from human HSCs, RGD peptide (100 mug/ml) reduced the expression of type I collagen and tissue inhibitor of matrix metalloproteinase-1, and increased that of matrix metalloproteinase-1. These results indicated that RGD peptides inhibited liver fibrosis associated with both decreased collagen production and increased collagenase acitivity, and suggested that RGD peptide might be useful for the therapy of hepatic fibrosis. 相似文献
87.
Nakashima Y Tagawa H Suzuki R Karnan S Karube K Ohshima K Muta K Nawata H Morishima Y Nakamura S Seto M 《Genes, chromosomes & cancer》2005,44(3):247-255
Natural killer (NK) cell lymphomas/leukemias are highly aggressive lymphoid malignancies, but little is known about their genomic alterations, and thus there is an urgent need for identification and analysis of NK cell lymphomas/leukemias. Recently, we developed our own array-based comparative genomic hybridization (array CGH) with an average resolution of 1.3 Mb. We performed an array CGH analysis for 27 NK-cell lymphoma/leukemia cases that were classified into two disease groups based on the World Health Organization Classification (10 aggressive NK-cell leukemia cases and 17 extranodal NK/T-cell [NK/T] lymphomas, nasal type). We identified the differences in the genomic alteration patterns of the two groups. The recurrent regions characteristic of the aggressive NK-cell leukemia group compared with those of the extranodal NK/T lymphoma, nasal-type group, were gain of 1q and loss of 7p15.1-p22.3 and 17p13.1. In particular, gain of 1q23.1-24.2 (P = 0.041) and 1q31.3-q44 (P = 0.003-0.047), and loss of 7p15.1-p22.3 (P = 0.012-0.041) and 17p13.1 (P = 0.012) occurred significantly more frequently in the former than in the latter group. Recurrent regions characteristic of the extranodal NK/T lymphoma, nasal-type group, compared with those of the other group were gain of 2q, and loss of 6q16.1-q27, 11q22.3-q23.3, 5p14.1-p14.3, 5q34-q35.3, 1p36.23-p36.33, 2p16.1-p16.3, 4q12, and 4q31.3-q32.1. Our results can be expected to provide further insights into the genetic basis of lymphomagenesis and the clinicopathologic features of NK-cell lymphomas/leukemias. 相似文献
88.
89.
Status asthmaticus is defined as an attack of bronchial asthma that resists conventional treatment and continues for more than 24 hours. We report here about patients with status asthmaticus who were successfully treated with isoflurane inhalation. Of the 19 patients who were transferred to the intensive care unit (ICU) and underwent mechanical ventilation from January 1996 to May 2001, eleven patients who were first treated by isoflurane inhalation were targeted in this study. Their improvement was assessed 6 and 24 hours after anesthesia compared with their condition before anesthesia. The tidal volume, pH, and PaCO2 improved within 6 hours after anesthesia. For the next step, among the patients who were transferred to the critical care center soon after an attack of bronchial asthma and underwent mechanical ventilation, 8 patients who were treated by isoflurane inhalation anesthesia (Group I) and another 4 patients who were not treated by isoflurane (Group NI) were compared to assess the usefulness of isoflurane inhalation therapy. The patients in Group I stayed in the ICU and underwent mechanical ventilation for a shorter period. These patients had hypotension and liver dysfunction after the inhalation anesthesia, but these symptoms were improved by decreasing the concentration of isoflurane. Isoflurane inhalation therapy seemed useful for intractable status asthmaticus, and earlier introduction of this therapy is expected to achieve a greater therapeutic effect. 相似文献
90.
Apoptotic body engulfment by a human stellate cell line is profibrogenic 总被引:22,自引:0,他引:22
Canbay A Taimr P Torok N Higuchi H Friedman S Gores GJ 《Laboratory investigation; a journal of technical methods and pathology》2003,83(5):655-663
Hepatocyte apoptosis and stellate cell activation are both features of chronic liver diseases, but a relationship between these events has not been explored. In macrophages, engulfment of apoptotic bodies induces expression of transforming growth factor-beta (TGF-beta), a profibrogenic cytokine. We examined whether a similar response occurs in stellate cells. Fluorescently labeled hepatocyte apoptotic bodies were added to cultures of primary and immortalized human stellate cells. Stellate cells, but not hepatocytes, readily engulfed apoptotic bodies in a time-dependent manner as assessed by confocal microscopy. The activation of primary and immortalized human stellate cells after incubation with apoptotic bodies, as well as their fibrogenic activity, was indicated by an increase in alpha-smooth muscle actin (primary cells), TGF-beta1, and collagen alpha1(I) mRNA (primary and immortalized cells). The profibrogenic response was dependent upon apoptotic body engulfment, because nocodazole, a microtubule-inhibiting agent, blocked both the engulfment and the increase of TGF-beta1 and collagen alpha1(I) mRNA. As described in primary rodent stellate cells, up-regulation of collagen alpha1(I) mRNA was inhibited by a PI-3K inhibitor (LY294002) and a p38 mitogen-activated protein kinase inhibitor (SB203580) in LX-1 cells. In conclusion, these data support a model in which engulfment of hepatocyte apoptotic bodies by stellate cells leads to a fibrogenic response by eliciting a kinase-signaling pathway. 相似文献