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91.
p21(Cip1/WAF1), known as a cell-cycle inhibitory protein, facilitates neurite outgrowth from neurons when present in the cytoplasm. The molecular mechanism of this action is that p21(Cip1/WAF1) forms a complex with Rho-kinase and inhibits its activity. As myelin-derived inhibitors of axonal outgrowth act on neurons by activating Rho, that is responsible for the lack of spontaneous regeneration of the injured central nervous system (CNS), Rho-kinase may be a good molecular target against injuries in the CNS. In this study, we delivered TAT-fusion protein of cytoplasmic p21(Cip1/WAF1) locally after dorsal hemisection of the thoracic spinal cord in rats. The treatment significantly stimulated axonal regeneration and recovery of hindlimb function, and inhibited the cavity formation in the spinal cord after the injury. Cytoplasmic p21(Cip1/WAF1) may provide a potential therapeutic agent that produces functional regeneration following CNS injuries. 相似文献
92.
Enhancing effects of oral adjuvants on anti-HBs responses induced by hepatitis B vaccine. 总被引:1,自引:0,他引:1 下载免费PDF全文
S Kuriyama T Tsujii S Ishizaka E Kikuchi K Kinoshita K Nishimura K Kitagami M Yoshikawa M Matsumoto 《Clinical and experimental immunology》1988,72(3):383-389
Hepatitis B (HB) vaccine is very promising for the prevention of HB infection. There exist, however, some non-responders to current vaccination trials. In this study, taurine, parotin and lithium were selected as adjuvants which can be administered orally. The mechanisms of these three materials as adjuvants and their effects on HB vaccine were investigated in mice. For instance, taurine induced polyclonal antibody production and exhibited adjuvant activity. Although taurine did not have any activity on the proliferation of thymocytes nor stimulate IL-2 production, taurine did induce IL-1 production by macrophages. It was considered that taurine-induced IL-1 would play an essential role in the proliferation and differentiation of B cells. Parotin also induced polyclonal antibody production and exhibited adjuvant activity. These effects of parotin were not affected even if macrophages or T cells were depleted, and parotin itself had an IL-1-like activity. Therefore, it was considered that parotin acted directly on B cells by its IL-1-like activity and mitogenic activity, resulting in the proliferation and differentiation of B cells. Lithium induced neither polyclonal antibody production, nor IL-1 or IL-2 production. However, when given with an antigen, lithium activated the humoral immune system, resulting in the augmentation of antibody production. Oral administration of taurine, parotin and lithium were capable of restoring antibody responses to HB surface antigen (HBsAg) in HBsAg-nonresponder mice. Furthermore, taurine, parotin and lithium enhanced the adjuvant effects of aluminium contained in the present HB vaccine. These observations indicate that use of these oral adjuvants may open new perspectives in the field of human HB vaccination. 相似文献
93.
Mice lacking smooth muscle calponin display increased bone formation that is associated with enhancement of bone morphogenetic protein responses 总被引:5,自引:0,他引:5
94.
Kenji Matsumoto Oh-Yong Kwon Hyungtae Kim Yukihiro Akao 《Developmental dynamics》2005,233(3):1149-1156
rck/p54 is a DEAD-box RNA helicase protein with ATP-dependent RNA-unwinding activity. Its ortholog is required for sexual reproduction in yeast and for oocyte survival and sperm fertility in Caenorhabditis elegans. In the current study, we investigated the expression of rck/p54 in mouse gametogenesis and early embryogenesis. Western blot analysis revealed that rck/p54 was highly expressed in both the ovary and testis. In the ovary, maturing oocytes strongly expressed rck/p54 in their cytoplasm. In contrast, in the testis, spermatogonia and primary spermatocytes highly expressed rck/p54 in their cytoplasm, but its expression decreased in the spermatids. Interestingly, rck/p54 was concentrated in the heads of spermatozoa; and then its expression gradually decreased as these cells matured along the epididymal duct. After fertilization, rck/p54 protein and its mRNA remained present in the pronucleus phase; and then their expression levels slightly but definitely decreased in morulae and blastocytes. The injection of a CMV-based rck/p54 expression vector into the pronuclei of fertilized eggs caused a delay in early embryogenesis. In generating RCK transgenic mice, the birth rate of the mice was significantly lower than those of other gene transgenic mice. These findings indicate that rck/p54 may play an important role in gametogenesis and early embryogenesis in mammals. 相似文献
95.
96.
Junji Furukawa Jitsuo Kiji Hisatoshi Konishi Kazuyoshi Yamamoto Shin-Ichi Mitani Susumu Yoshikawa 《Macromolecular chemistry and physics.》1973,174(1):65-71
The behavior of hydridonickel coordination compounds as catalysts for the oligomerization and polymerization of butadiene in various solvents was studied. In the presence of alcohol bis(tricyclohexylphosphine)chlorohydridonickel ( 4 , X = Cl) (HNiCl[P(C6H11)3]2) catalyzes the linear dimerization. With hydridotetrakis(phosphite)nickel(1+) ( 2 ) ([HNi{P(OR)3}4]+), which is prepared from tetrakis(phosphite)nickel ( 1 ) (Ni[P(OR)3]4) and trifluoroacetic acid, dimerization occurs in sec-alcohol but there is no reaction in tert-alcohol. The main product is 2-methylenevinylcyclopentane ( 8 ). The other products are 4-vinylcyclohexene ( 10 ), 1,5-cyclooctadiene ( 5 ), 1,3,7-octatriene ( 7 ) and 1,3,6-octatriene ( 9 ). The hydridonickel coordination compound, prepared with inorganic acids, does not afford the dimers but the 1,4-trans polymer. 相似文献
97.
98.
Maeda T Iwasaki A Kawahito S Nakata K Nonaka K Linneweber J Schulte-Eistrup S Takano T Yoshikawa M Sato K Kuwana J Murabayashi S Nosé Y 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2000,46(4):426-430
A silicone membrane hollow fiber oxygenator applicable for use as an extracorporeal membrane oxygenator (ECMO) has been developed in our laboratory. This silicone hollow fiber displays astonishing mechanical stability, is barely compressible or stretchable, and assembles easily while maintaining good gas permeability. The priming volume is 140 cc with a surface area of 0.8 m2. This study evaluated the gas transfer performances and biocompatibility of the oxygenator under ECMO and CPB conditions. In vitro studies that were performed at a blood flow rate of 2 L/min, and revealed O2 and CO2 gas transfer rates of 82.35 +/- 0.56 ml/m2/L/min and 38.72 +/- 2.88 ml/m2/L/min, respectively. The commercially available Kolobow (Avecor 1500) oxygenator was used as the control, and had O2 and CO2 gas transfer rates of 53.8 +/- 0.5 ml/m2/L/min and 24.7 +/- 2.0 ml/m2/L/min. To evaluate blood trauma, Normalized Index of Hemolysis (NIH) was measured according to American Society of Testing and Materials (ASTM) standards. The NIH findings were 0.0112 g/100L at a blood flow of 1 L/min, and 0.0152 g/100L at 5 L/min. Three ex vivo experiments, using a blood flow rate of 1 L/min, were performed with venoarterial bypass, and O2 transfer rate and CO2 transfer rate of the oxygenators were well maintained. This indicates that this preclinical silicone membrane hollow fiber oxygenator has superior efficiency, less blood trauma, and is smaller when compared with the only clinically available Kolobow oxygenator. 相似文献
99.
Lean body mass and bone mineral density in physically exercising postmenopausal women 总被引:3,自引:0,他引:3
OBJECTIVES: To investigate whether the relative contribution of body composition (lean and fat mass component) to postmenopausal bone mineral density (BMD) differs between women participating in physical exercise and sedentary women. METHODS: Subjects were 45 postmenopausal women participating in regular physical exercise and 89 sedentary controls aged 50-60 years. Baseline characteristics included age, height, weight, body mass index (BMI, Wt/Ht(2)), age at menopause, and years since menopause (YSM). Body fat mass, percentage of body fat, lean body mass, and lumbar spine BMD (L2-4) were measured by dual-energy X-ray absorptiometry. RESULTS: Although age, height, weight, BMI, and YSM did not differ between the two groups, lean body mass and lumbar spine BMD were significantly higher (P<0.05 and <0.001, respectively), while body fat mass and percentage of body fat mass were significantly lower in exercising women than in sedentary controls (P<0.05 and <0.05, respectively). In exercising women, BMD was positively correlated with lean body mass (r=0.415, P<0.01) but not with body fat mass (r=0.155, NS). Conversely, in sedentary controls, BMD was correlated with body fat mass (r=0.251, P<0.05) and lean body mass (r=0.228, P<0.05). CONCLUSIONS: Lean body mass is a more significant determinant of postmenopausal BMD in physically exercising women than in sedentary women. 相似文献
100.
This article explores the implications of recent welfare-related policy change for the well-being of children in low-income families, and for research investigating child development processes and outcomes. It provides an overview of current welfare-related policies and explores the implications for developmental researchers. The article also synthesizes early findings from research, highlighting both overall impacts and the more nuanced evidence that while families are transitioning off welfare, only a small number are transitioning out of poverty, and a subgroup of families at risk are not faring well. It then examines, from a theoretical and methodological framework, what developmental psychopathology might bring to the study of welfare-related impacts on children in the context of this complex and changing policy landscape, and what welfare researchers might bring to the field of developmental psychopathology. The article concludes with broad recommendations for both research and policy. 相似文献