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101.
The authors investigated the intracellular signal transduction for interleukin (IL)-1 beta-induced endothelin (ET) production by endothelial cells from cultured human umbilical vein (HUVEC). Cultured HUVEC released immunoreactive (iR)-ET into the media in a time-dependent manner and a significant increase of iR-ET production was observed by the addition of IL-1 beta. The stimulating effect of IL-1 beta on iR-ET production was respectively inhibited by protein kinase C (C kinase) inhibitor (H-7), Ca-calmodulin inhibitor (W-7), cyclic AMP-dependent protein kinase (A kinase) inhibitor (H-8) and tyrosine kinase inhibitor (genistain) in a dose-dependent fashion. The data suggested that intracellular signal transduction for IL-1 beta-induced iR-ET production were via such pathways as C kinase, A kinase, Ca-calmodulin and tyrosine kinase in combination or independently, though possible mediation by other pathways cannot be ruled out.  相似文献   
102.
Iron-deficiency anemia leads directly to both reduced hemoglobin levels and work performance in humans and experimental animals. In an attempt to observe a direct link between work performance and insufficient iron at the cellular level, we produced severe iron deficiency in female weanling Sprague-Dawley rats following five weeks on a low-iron diet. Deficient rats were compared with normal animals to observe major changes in hematological parameters, body weight, and growth of certain organs and tissues. The overall growth of iron-deficient animals was approximately 50% of normal. The ratio of organ weight: body weight increased in heart, liver, spleen, kidney, brain, and soleus muscle in response to iron deficiency. Further, mitochondria from heart and red muscle retained their iron more effectively under the stress of iron deficiency than mitochondria from liver and spleen. Metabolism of iron in normal and depleted tissue was measured using tracer amounts of59Fe administered orally. As expected, there was greater uptake of tracer iron by iron-deficient animals. The major organ of iron accumulation was the spleen, but significant amounts of isotope were also localized in heart and brain. In all muscle tissue examined the59Fe preferentially entered the mitochondria. Enhanced mitochondrial uptake of iron prior to any detectable change in the hemoglobin level in experimental animals may be indicative of nonhemoglobin related biochemical changes and/or decrements in work capacity.  相似文献   
103.
In crustaceans, the pigment-dispersing hormone (PDH) is released from the X-organ/sinus gland complex located in the eyestalks, and controls pigment dispersion in the chromatophores. Knowledge concerning the structure and activity of PDH in penaeid shrimps is remains limited, since natural PDH has been purified from only the Kuruma prawn, Marsupenaeus japonicus. In this study, two PDHs (Liv-PDH-A and -B) were purified from the sinus gland extracts of another penaeid species, the whiteleg shrimp, Litopenaeus vannamei, by two steps of reversed-phase HPLC, and their amino acid sequences were determined. They both consist of 18 amino acid residues, with a free N-terminus and an amidated C-terminus, the sequences of Liv-PDH-A and -B being NSELINSLLGIPKVMNDAamide and NSELINSLLGLPKVMNDAamide, respectively. These sequences are identical to those of mature PDHs deduced from cDNAs encoding L. vannamei PDH precursors cloned previously by other workers. Liv-PDH-A and -B showed significant pigment-dispersing activity in melanophores by in vivo bioassay.  相似文献   
104.
(1S,3R)-1-Aminocyclopentane-1,3-dicarboxylic acid (ACPD), a potent agonist of metabotropic glutamate receptors, was synthesized from L-serine. The chiral quaternary center was constructed by C-H insertion of the alkylidenecarbene, this being generated by the reaction between lithiotrimethylsilyldiazomethane and the corresponding ketone.  相似文献   
105.

Purpose

To evaluate the postoperative changes in blebs and levels of aqueous monocyte chemotactic protein-1 (MCP-1) after trabeculectomy vs. Ex-PRESS tube shunt surgery.

Methods

Rabbits were subjected to trabeculectomy or Ex-PRESS tube shunt surgery and observed for up to 3 months. Intraocular pressure (IOP) was measured using a rebound tonometer. The MCP-1 level was measured by enzyme-linked immunosorbent assay (ELISA). Bleb morphology was evaluated using photos and anterior-segment optical coherence tomography (OCT).

Results

There were no differences in bleb appearance or IOP at any time between the groups. Bleb wall density in the anterior-segment OCT image was significantly lower 1 week after surgery in the Ex-PRESS group than the trabeculectomy group. The MCP-1 level in control eyes was 304.1 ± 45.2 pg/mL. In the trabeculectomy group, the mean aqueous MCP-1 level was 1444.9, 1914.3, 1899.8, 516.4, 398.3, 427.3, 609.5, 1612.7, 386.2, and 167.9 pg/mL at 3, 6, and 12 h, and 1, 2, 5, 7, 14, 30, and 90 days after surgery, respectively. In the Ex-PRESS group, the corresponding values were 1744.0, 1372.0, 932.5, 711.7, 396.1, 487.3, 799.5, 1327.9, 293.6, and 184.0 pg/mL. There were no significant differences in the aqueous MCP-1 level between the groups at any time point.

Conclusion

The postoperative changes were similar in the Ex-PRESS and trabeculectomy groups, except for bleb wall density in the anterior-segment OCT image. The postoperative aqueous MCP-1 level had bimodal peaks in both groups.  相似文献   
106.
Psoriasis is a common human skin disease whereby abnormal production of inflammatory mediators is believed to play an important role in its pathogenesis. The IL12B gene, which encodes the shared IL-12p40 subunit in two cytokines, IL-12 and IL-23, and the IL23R gene, which encodes a subunit of the receptor for IL-23, were identified as psoriasis-susceptibility genetic factors in recent candidate gene and genome-wide association studies of Chinese and Europeans. Since there are significant differences in the incidence of psoriasis between Europeans and Japanese suggesting a genetic ethnic effect, we examined the association of IL12B and IL23R gene polymorphisms with psoriasis in a cohort of Japanese. In this study, we genotyped two SNPs (rs3212227 and rs6887695) in the IL12B gene and one SNP (rs11209026) in the IL23R gene using 560 Japanese psoriasis cases and 560 controls and compared our results with those previously published for Europeans and Asians. Our study showed significant associations between psoriasis and both IL12B gene SNPs, rs3212227 (odds ratio (OR)?=?1.35, P?=?4.94E-04) and rs6887695 (OR?=?1.32, P?=?2.00E-03), but no significant association between psoriasis and the IL23R SNP, rs11209026. Furthermore, a significant haplotype association was found for the IL12B gene protective haplotype C-C (OR?=?0.71, P?=?1.84E-04) in Japanese, as previously elucidated in the studies of European ancestry.  相似文献   
107.

Background

To investigate the function of the intestinal Vdr gene in inflammatory bowel disease (IBD), in conjunction with the discovery of possible metabolic markers for IBD using intestine-specific Vdr knockout mice.

Methods

VdrΔIEpC mice were generated, phenotyped and treated with a time-course of 3% dextran sulfate sodium (DSS) to induce colitis. Colitis was diagnosed by evaluating clinical symptoms and intestinal histopathology. Gene expression analysis was carried out. In addition, metabolic markers of IBD were explored by metabolomics.

Results

VdrΔIEpC mice showed abnormal body size, colon structures and feces color. Calcium, collagen, and intestinal proliferation-related gene expression were all decreased, and serum alkaline phosphatase was highly increased. In the acute model which was treated with 3% DSS for six days, VdrΔIEpC mice showed a high score of IBD symptoms; enlarged mucosal layer and damaged muscularis layer. In the recovery experiment model, where mice were treated with 3% DSS for four days and water for three days, VdrΔIEpC mice showed a high score of IBD symptoms; severe damage of mucosal layer and increased expression of genes encoding proinflammatory cytokines. Feces metabolomics revealed decreased concentrations of taurine, taurocholic acid, taurodeoxycholic acid and cholic acid in VdrΔIEpC mice.

Conclusions

Disruption of the intestinal Vdr gene showed phenotypical changes that may exacerbate IBD. These results suggest that VDR may play an important role in IBD.General significanceVDR function has been implicated in IBD. This is of value for understanding the etiology of IBD and for development of diagnostic biomarkers for IBD.  相似文献   
108.
The effects of supplementation with creatine (Cr) and its analog, β-guanidinopropionic acid (β-GPA), on the differentiation of myoblasts and the numbers of nucleoli were studied in C2C12 cells. The cells were cultured in differentiation medium for 4 d. Then Cr (1 mM) or β-GPA (1 mM) was added to the cells, and the mixture was cultured for an additional 2 d. Although the number of myotubes was not different among the groups, myotube diameters and nuclear numbers in myotubes were increased by Cr and β-GPA treatment respectively. The expression of differentiation marker proteins, myogenin, and the myosine heavy chain, was increased in the β-GPA group. Supplementation with β-GPA also increased the percentage of p21 (inhibitor for cell cycle progression)-positive myoblasts. Supplementation with Cr inhibited the decrease in nucleoli numbers, whereas β-GPA increased nucleolar sizes in the myotubes. These results suggest that β-GPA supplementation stimulated the differentiation of myoblasts into multi-nucleated myotubes through induction of p21 expression.  相似文献   
109.
The incidence of falls in the elderly is increasing with the aging of society and is becoming a major public health issue. From the viewpoint of prevention of falls, it is important to evaluate the stability of the gait in the elderly people. The pelvic movement, which is a critical factor for walking stability, was analyzed using a posture monitoring system equipped with a triaxial accelerometer and a gyroscope. The subjects were 95 elderly people over 60 years of age. The criteria for instability were open-eye standing on one leg for 15s or less, and 11s or more on 3m timed up and go test. Forty subjects who did not meet both of these criteria comprised the stable group, and the remaining 55 subjects comprised the unstable group. Pelvic movement during walking was compared between the two groups. The angle, angular velocity, and acceleration were analyzed based on the wave shape derived from the device worn around the second sacral. The results indicated that pelvic movement was lower in all three directions in the unstable group compared to the stable group, and the changes in the pelvic movement during walking in unstable elderly people were also reduced. This report is the first to evaluate pelvic movement by both a triaxial accelerometer and a triaxial gyroscope simultaneously. The characteristics of pelvic movement during walking can be applied in screening to identify elderly people with instability, which is the main risk factor associated with falls.  相似文献   
110.
We analyzed the lung mRNA expression profiles of a murine model of COPD developed using a lung-specific IL-18-transgenic mouse. In this transgenic mouse, the expression of 608 genes was found to vary more than 2-fold in comparison with control WT mice, and was clustered into 4 groups. The expression of 140 genes was constitutively increased at all ages, 215 genes increased gradually with aging, 171 genes decreased gradually with aging, and 82 genes decreased temporarily at 9 weeks of age. Interestingly, the levels of mRNA for the chitinase-related genes chitinase 3-like 1 (Chi3l1), Chi3l3, and acidic mammalian chitinase (AMCase) were significantly higher in the lungs of transgenic mice than in control mice. The level of Chi3l1 protein increased significantly with aging in the lungs and sera of IL-18 transgenic, but not WT mice. Previous studies have suggested Chi3l3 and AMCase are IL-13-driven chitinase-like proteins. However, IL-13 gene deletion did not reduce the level of Chi3l1 protein in the lungs of IL-18 transgenic mice. Based on our murine model gene expression data, we analyzed the protein level of YKL-40, the human homolog of Chi3l1, in sera of smokers and COPD patients. Sixteen COPD patients had undergone high resolution computed tomography (HRCT) examination. Emphysema was assessed by using a density mask with a cutoff of -950 Hounsfield units to calculate the low-attenuation area percentage (LAA%). We observed significantly higher serum levels in samples from 28 smokers and 45 COPD patients compared to 30 non-smokers. In COPD patients, there was a significant negative correlation between serum level of YKL-40 and %FEV(1). Moreover, there was a significant positive correlation between the serum levels of YKL-40 and LAA% in COPD patients. Thus our results suggest that chitinase-related genes may play an important role in establishing pulmonary inflammation and emphysematous changes in smokers and COPD patients.  相似文献   
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