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121.
Cluster of differentiation 69 (CD69) has been identified as a lymphocyte early activation marker, and recent studies have indicated that CD69 mediates intracellular signals and plays an important role in various inflammatory diseases. Cigarette smoke (CS) is a strong proinflammatory stimulus that induces the release of proinflammatory mediators by recruiting macrophages and neutrophils into the lung tissue, and is one of the main risk factors for a number of chronic diseases. However, the potential role of CD69 in CS-induced pulmonary inflammation has not been determined. To address to this question, CD69-deficient (KO) and wild-type (WT) mice were subjected to CS-induced acute pulmonary inflammation. After the exposure with CS, the expression of CD69 in the lung of WT mice was significantly induced, it was predominantly observed in macrophages. In conjunction with this phenomenon, neutrophil and macrophage cell counts, and expression of several cytokines were significantly higher in the bronchoalveolar lavage fluid (BALF) of CS-exposed WT mice compared with air-exposed WT mice. Likewise, the CS-induced accumulation of inflammatory cells and cytokines expression were significantly lower in CD69-KO mice than in WT mice. These results suggest that CD69 on macrophages is involved in CS-induced acute pulmonary inflammation.  相似文献   
122.
The lactoside with PEG-fluorous tag was introduced to BHK-21(C-13) cells to generate a GM3-type oligosaccharide (Siaα2-3Galβ1-4Glc). The GM3-type oligosaccharide obtained was easily immobilized by spotting onto commercially available polytetrafluoroethylene (PTFE) filter through non-covalent fluorous affinity and simply assessed by dot blot method using the interaction of carbohydrate- with proteins which recognize sialic acid such as virus membrane proteins.  相似文献   
123.
In this work, we attempted to assess the effects of inoculation of arbuscular mycorrhizal fungus (AMF), Glomus clarum, on the survival and development of micropropagated Jatropha curcas plantlets at different rooting stages. Elongated shoots (average 3?cm) of J. curcas, maintained for 0, 14, or 21?days on rooting medium in the presence or absence of 1?mg?L?1 indole-3-butyric acid (IBA), were transferred to a sand:soil:vermiculite (1:1/2:1) (v:v:v) substrate. At the time of transplantation, the plantlets were either inoculated or not inoculated with G. clarum that had been monoaxenically produced in Ri-transformed carrot roots. After a 2-week acclimatization period, 100?% of the plants kept for 0 or 14?days in rooting medium survived. However, those that remained for 21?days in rooting medium displayed post-acclimatization survival rates of 93 and 89?% for plants inoculated and non-inoculated with G. clarum, respectively. Colonization rates ranged from 70 to 93?%, and the stimulatory effects of AMF were evidenced by increased phosphorus uptake by plants and increases in all evaluated growth parameters, except plant height. Plants that were not subjected to the rooting stage showed growth similar to or higher than those subjected to the rooting stage, regardless of the addition of IBA. It can be concluded that stimulatory effects of mycorrhizal fungi were observed, and that the inoculation of J. curcas proved effective during the initial period of the acclimatization phase.  相似文献   
124.
AimsCD69 is an early activation marker in lymphocytes and an important signal transmitter in inflammatory processes. However, its role in acute lung injury (ALI) is still unknown. We used a lipopolysaccharide (LPS)-induced mouse model of ALI to study the role of macrophage-surface CD69 in this condition.Main methodsWe investigated bronchoalveolar lavage fluid (BALF) cell subpopulations, myeloperoxidase levels in lung homogenates, lung pathology, and lung oedema in CD69-deficient (CD69?/?) mice 24 h after LPS instillation. We also determined cytokine/chemokine expression levels in BALF and macrophage culture supernatant from CD69?/? and wild type (WT) mice. Also, we investigated CD69, keratinocyte-derived chemokine (KC) and macrophage inflammatory protein (MIP)-2 localization in the lungs after LPS administration. Furthermore, we examined the effect of anti-CD69 antibody on LPS-induced cytokine/chemokine release from cultured macrophages.Key findingsOur study shows that intratracheal instillation of LPS-induced neutrophilic infiltration, histopathological changes, myeloperoxidase positivity, and oedema in the lung to a lower degree in CD69?/? mice than in WT mice. The immunoreactivities for CD69, KC and MIP2 were induced in the lung of WT mice instilled with LPS and were predominantly localized to the macrophages. Moreover, the cytokine/chemokine expression profile between the two genotypes of cultured macrophages in response to LPS was similar to that observed in the BALF. In addition, anti-CD69 antibody inhibited the LPS-induced cytokine/chemokine expression.SignificanceThese results suggest that CD69 on macrophages plays a crucial role in the progression of LPS-induced ALI and may be a potentially useful target in the therapy for ALI.  相似文献   
125.
In this study, we developed new 3′-terminal deoxyribonucleoside-loading reagents 1 with a new silyl-type linker. These reagents could increase the efficiency of introduction of 3′-terminal deoxyribonucleoside components into polymer supports to a level of 17–29 μmol/g. The efficiency was higher than that of previous T-loading reagents because reagents 1 contain a 4-aminobutyryl residue as a spacer. Moreover, we could synthesize not only unmodified DNA oligomers but also a base-labile modified DNA oligomer using resins 9a–d in the activated phosphite method without base protection.  相似文献   
126.
The question why females in many species mate with several males (polyandry) has engaged the interest of evolutionary biologists for many years, and many studies have been conducted on the nature of the benefits that the females gain from polyandry. To understand the variation of female mating rates among species and populations it is indispensable to test the prediction that females of more polyandrous populations experience larger fitness benefit than those of less polyandrous populations. We compared the fitness components of two strains of the adzuki bean beetle Callosobruchus chinensis that have genetically different female mating rates. We measured the number of hatched eggs of once-copulated females and twice-copulated females in each strain. The statistical interaction for the number of hatched eggs between the number of matings and strains was determined. The increase in the number of hatched eggs is larger for the lower mating-rate strain than for the higher mating rate strain. This means that females of the lower mating-rate strain would have larger fitness gain from polyandry than those of the higher mating-rate strain. The actual mating rates of females did not reflect female interests in adzuki bean beetles, suggesting they are affected by sexual conflict.  相似文献   
127.
Shibasaki H  Tanabe C  Furuta T  Kasuya Y 《Steroids》2001,66(11):795-801
This study describes the enzymatic hydrolysis of urinary conjugates of cortisol, cortisone, tetrahydrocortisol, allotetrahydrocortisol, and tetrahydrocortisone with beta-glucuronidase preparations from Helix pomatia and Ampullaria. The objective of the present studies was to find optimal hydrolysis conditions for these conjugated steroids. Assay of the isolated steroids was carried out by GC-MS using deuterium-labeled compounds as internal standards. The allotetrahydrocortisol conjugate was clearly the hardest to hydrolyze with enzyme from Helix pomatia and required increased enzyme concentration and prolonged incubation. Hydrolysis of a urine sample for 2.0 h with the simultaneous use of 3400 units/ml Ampullaria and 5400 units/ml Helix pomatia enzymes in 0.5 M acetate buffer at 55 degrees C achieved more complete cleavage of the urinary conjugates of the five steroids examined. It is thus advantageous to use the Ampullaria and Helix pomatia enzymes in combination to obtain the highest yield in the urinary corticosteroid assay.  相似文献   
128.
A DNA fragment carrying the gene encoding poly(3-hydroxybutyrate) (P(3HB)) depolymerase was cloned from the genomic DNA of Marinobacter sp. DNA sequencing analysis revealed that the Marinobacter sp. P(3HB) depolymerase gene is composed of 1734 bp and encodes 578 amino acids with a molecular mass of 61,757 Da. A sequence homology search showed that the deduced protein contains the signal peptide, catalytic domain (CD), cadherin-type linker domain (LD), and two substrate-binding domain (SBD). The fusion proteins of glutathione S-transferase (GST) with the CD showed the hydrolytic activity for denatured P(3HB) (dP(3HB)), P(3HB) emulsion (eP(3HB)) and p-nitrophenylbutyrate. On the other hand, the fusion proteins lacking the SBD showed much lower hydrolytic activity for dP(3HB) compared to the proteins containing both CD and SBD. In addition, binding tests revealed that the SBDs are specifically bound not to eP(3HB) but dP(3HB). These suggest that the SBDs play a crucial role in the enzymatic hydrolysis of dP(3HB) that is a solid substrate.  相似文献   
129.
The LG4 module of the laminin alpha 3 chain (alpha 3 LG4), a component of epithelial-specific laminin-5, has cell attachment activity and binds syndecan (Utani, A., Nomizu, M., Matsuura, H., Kato, K., Kobayashi, T., Takeda, U., Aota, S., Nielsen, P. K., and Shinkai, H. (2001) J. Biol. Chem. 276, 28779-28788). Here, we show that recombinant alpha 3 LG4 and a 19-mer synthetic peptide (A3G756) within alpha 3 LG4 active for syndecan binding increased the expression of matrix metalloproteinase-1 (MMP-1) in keratinocytes and fibroblasts. This induction was inhibited by heparin and required de novo synthesis of proteins. In keratinocytes, A3G756 up-regulated interleukin (IL)-1 beta and MMP-1 expression and an IL-1 receptor antagonist thoroughly inhibited A3G756-mediated induction of MMP-1. A3G756 also activated p38 mitogen-activated protein kinase (p38 MAPK) and extracellular signal-related kinase (Erk). Studies with specific inhibitors of MAPKs showed that p38 MAPK activation was necessary for both IL-1 beta and MMP-1 induction, but Erk activation was required only for MMP-1 induction. In fibroblasts, IL-1 receptor antagonist did not block A3G756-mediated induction of MMP-1. These results indicated that induction of MMP-1 by alpha 3 LG4 is mediated through the IL-1 beta autocrine loop in keratinocytes but the mechanism of the induction in fibroblasts is different. Our study suggests that the laminin alpha 3 LG4 module may play an important role in tissue remodeling by inducing MMP-1 expression during wound healing.  相似文献   
130.
An HPLC method for determining quercetin in human plasma and urine is presented for application to the pharmacokinetic study of rutin. Isocratic reversed-phase HPLC was employed for the quantitative analysis by using kaempferol as an internal standard. Solid-phase extraction was performed on an Oasis HLB cartridge (>95% recovery). The HPLC assay was carried out using a Luna ODS-2 column (150 x 2.1 mm I.D., 5 microm particle size). The mobile phase was acetonitrile-10 mM ammonium acetate solution containing 0.3 mM EDTA-glacial acetic acid, 29:70:1 (v/v, pH 3.9) and 26:73:1 (v/v, pH 3.9) for the determination of plasma and urinary quercetin, respectively. The flow-rate was 0.3 ml/min and the detection wavelength was set at 370 nm. Calibration of the overall analytical procedure gave a linear signal (r>0.999) over a concentration range of 4-700 ng/ml of quercetin in plasma and 20-1000 ng/ml of quercetin in urine. The lower limit of quantification was approximately 7 ng/ml of quercetin in plasma and approximately 35 ng/ml in urine. The detection limit (defined at a signal-to-noise ratio of about 3) was approximately 0.35 ng/ml in plasma and urine. A preliminary experiment to investigate the plasma concentration and urinary excretion of quercetin after oral administration of 200 mg of rutin to a healthy volunteer demonstrated that the present method was suitable for determining quercetin in human plasma and urine.  相似文献   
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