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61.
To investigate the ability of 1.8 kb or 3.1 kb bovine beta-casein promoter sequences for the expression regulation of transgene in vivo, transgenic mice were produced with human type II collagen gene fused to 1.8 kb and 3.1 kb of bovine beta-casein promoter by DNA microinjection. Five and three transgenic founder mice were produced using transgene constructs with 1.8 kb and 3.1 kb of bovine beta-casein promoters respectively. Founder mice were outbred with the wild type to produce F1 and F2 progenies. Total RNAs were extracted from four tissues (mammary gland, liver, kidney, and muscle) of female F1 transgenic mice of each transgenic line following parturition. RT-PCR and Northern blot analysis revealed that the expression level of transgene was variable among the transgenic lines, but transgenic mice containing 1.8 kb of promoter sequences exhibited more leaky expression of transgene in other tissues compared to those with 3.1 kb promoter. Moreover, Western blot analysis of transgenic mouse milk showed that human type II collagen proteins secreted into the milk of lactating transgenic mice contained 1.8 kb and 3.1 kb of bovine beta-casein promoter. These results suggest that promoter sequences of 3.1 kb bovine beta-casein gene can be used for induction of mammary gland-specific expression of transgenes in transgenic animals.  相似文献   
62.
BACKGROUND: Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) induces cell death in various tumor cells, but relatively spares normal cells. Recombinant adeno-associated virus (rAAV) vectors have a number of advantages including in vivo long-term gene expression. Here, we assessed the biological activity of a novel, secreted form of TRAIL (sTRAIL) for cancer gene therapy using a rAAV2 vector. METHODS: A plasmid and rAAV2 vectors were constructed encoding sTRAIL composed of a leader sequence, the isoleucine zipper, and the active domain of TRAIL (aa 95-281). The functionality of sTRAIL was validated by cell viability, FACS analysis, caspase-3 activity, and TUNEL staining. rAAV-sTRAIL was injected intratumorally to nude mice bearing human A549 lung tumor cells. Nude mice received A549 tumor cells after intravenous delivery of rAAV-sTRAIL. The antitumor effect was then evaluated by measuring tumor regression and occurrence in the experimental animal. RESULTS: sTRAIL was released from cells transfected with the sTRAIL expression construct or transduced with rAAV-sTRAIL, and induced apoptosis in cancer cells, but spared normal fibroblast cells. Secreted sTRAIL formed oligomers including trimers with intersubunit disulfide. Purified sTRAIL exerted much lower cytotoxicity on primary human hepatocytes compared to recombinant TRAIL. Intratumoral delivery of rAAV-sTRAIL significantly inhibited growth of A549 tumors established in nude mice. A number of apoptotic tumor cells were detected by TUNEL staining in mice treated with rAAV-sTRAIL. Systemic pretreatment with rAAV-sTRAIL significantly inhibited tumor formation in nude mice. CONCLUSION: The results suggest that rAAV-sTRAIL may be useful for local or systemic cancer gene therapy for treating TRAIL-sensitive tumors.  相似文献   
63.
The present study investigated the antifatigue effects of Panax ginseng C.A. Meyer in 90 subjects (21 men and 69 women) with idiopathic chronic fatigue (ICF) in a randomised, double-blind, placebo-controlled and parallel designed trial. A bespoke 20% ethanol extract of P. ginseng (1 g or 2 g day–1) or a placebo was administered to each group for 4 weeks, and then fatigue severity was monitored using a self-rating numeric scale (NRS) and a visual analogue scale (VAS) as a primary endpoint. Serum levels of reactive oxygen species (ROS), malondialdehyde (MDA), total glutathione (GSH) contents and glutathione reductase (GSH-Rd) activity were determined. After 4-week, P. ginseng administration decreased the total NRS score, but they were not statistically significant compared with placebo (P>0.05). Mental NRS score was significantly improved by P. ginseng administrations as 20.4±5.0 to 15.1±6.5 [95% CI 2.3∼8.2] for 1 g and 20.7±6.3 to 13.8±6.2 [95% CI −0.1∼4.2] for 2 g compared with placebo 20.9±4.5 to 18.8±2.9 [95% CI 4.1∼9.9, P<0.01]. Only 2 g P. ginseng significantly reduced the VAS score from 7.3±1.3 to 4.4±1.8 [95% CI 0.7∼1.8] compared with the placebo 7.1±1.0 to 5.8±1.3 [95% CI 2.2 ∼3.7, P<0.01]. ROS and MDA levels were lowered by P. ginseng compared to placebo. P. ginseng 1 g increased GSH concentration and GSH-Rd activity. Our results provide the first evidence of the antifatigue effects of P. ginseng in patients with ICF, and we submit that these changes in antioxidant properties contribute in part to its mechanism.

Trial Registration

Clinical Research Information Service (CRIS) KCT0000048  相似文献   
64.
Calcineurin is a calcium-activated phosphatase to mediate lymphocyte activation and neuron signaling, but its role in inflammatory arthritis remains largely unknown. In this study, we demonstrate that calcineurin was highly expressed in the lining layer, infiltrating leukocytes, and endothelial cells of rheumatoid synovium. The basal expression levels of calcineurin were higher in the cultured synoviocytes of rheumatoid arthritis patients than those of osteoarthritis patients. The calcineurin activity in the synoviocytes was increased by the stimulation with proinflammatory cytokines such as IL-1beta and TNF-alpha. Moreover, rheumatoid arthritis synoviocytes had an enlarged intracellular Ca(2+) store and showed a higher degree of [Ca(2+)](i) release for calcineurin activity than osteoarthritis synoviocytes when stimulated with either TNF-alpha or phorbol myristate acetate. IL-10, an anti-inflammatory cytokine, failed to increase the Ca(2+) and calcineurin activity. The targeted inhibition of calcineurin by the overexpression of calcineurin-binding protein 1, a natural calcineurin antagonist, inhibited the production of IL-6 and matrix metalloproteinase-2 by rheumatoid synoviocytes in a similar manner to the calcineurin inhibitor, cyclosporin A. Moreover, the abundant calcineurin expression was found in the invading pannus in the joints of mice with collagen-induced arthritis. In these mice, calcineurin activity in the cultured synovial and lymph node cells correlated well with the severity of arthritis, but which was suppressed by cyclosporin A treatment. Taken together, our data suggest that the abnormal activation of Ca(2+) and calcineurin in the synoviocytes may contribute to the pathogenesis of chronic arthritis and thus provide a potential target for controlling inflammatory arthritis.  相似文献   
65.

Background

Knee osteoarthritis (OA) is the most common joint disease of adults worldwide. Since the treatments for advanced radiographic knee OA are limited, clinicians face a significant challenge of identifying patients who are at high risk of OA in a timely and appropriate way. Therefore, we developed a simple self-assessment scoring system and an improved artificial neural network (ANN) model for knee OA.

Methods

The Fifth Korea National Health and Nutrition Examination Surveys (KNHANES V-1) data were used to develop a scoring system and ANN for radiographic knee OA. A logistic regression analysis was used to determine the predictors of the scoring system. The ANN was constructed using 1777 participants and validated internally on 888 participants in the KNHANES V-1. The predictors of the scoring system were selected as the inputs of the ANN. External validation was performed using 4731 participants in the Osteoarthritis Initiative (OAI). Area under the curve (AUC) of the receiver operating characteristic was calculated to compare the prediction models.

Results

The scoring system and ANN were built using the independent predictors including sex, age, body mass index, educational status, hypertension, moderate physical activity, and knee pain. In the internal validation, both scoring system and ANN predicted radiographic knee OA (AUC 0.73 versus 0.81, p<0.001) and symptomatic knee OA (AUC 0.88 versus 0.94, p<0.001) with good discriminative ability. In the external validation, both scoring system and ANN showed lower discriminative ability in predicting radiographic knee OA (AUC 0.62 versus 0.67, p<0.001) and symptomatic knee OA (AUC 0.70 versus 0.76, p<0.001).

Conclusions

The self-assessment scoring system may be useful for identifying the adults at high risk for knee OA. The performance of the scoring system is improved significantly by the ANN. We provided an ANN calculator to simply predict the knee OA risk.  相似文献   
66.

Background

Peptidylglycine-α-amidating monooxygenase (PAM) may play a role in the secretion of atrial natriuretic peptide (ANP), which is a hormone involved in the maintenance of blood pressure (BP). The objective of the present study was to determine whether PAM is a novel candidate gene for hypertension (HTN).

Results

A total of 2153 Korean participants with normotension and HTN were included. Genotype data were obtained using the Korean Chip. The rs13175330 polymorphism of the PAM gene was selected from the ten single nucleotide polymorphisms (SNPs) most strongly associated with BP. The presence of the G allele of the PAM rs13175330 A>G SNP was associated with a higher risk of HTN after adjustments for age, sex, BMI, smoking, and drinking [OR 1.607 (95% CI 1.220–2.116), p?=?0.001]. The rs13175330 G allele carriers in the HTN group treated without antihypertensive therapy (HTN w/o therapy) had significantly higher systolic and diastolic BP than the AA carriers, whereas the G allele carriers in the HTN group treated with antihypertensive therapy (HTN w/ therapy) showed significantly higher diastolic BP. Furthermore, rs13175330 G allele carriers in the HTN w/o therapy group had significantly increased levels of insulin, insulin resistance, and oxidized low-density lipoprotein (LDL) and significantly decreased LDL-cholesterol levels and LDL particle sizes compared to the AA carriers.

Conclusion

These results suggest that the PAM rs13175330 A>G SNP is a novel candidate gene for HTN in the Korean population. Additionally, the PAM rs13175330 G allele might be associated with insulin resistance and LDL atherogenicity in patients with HTN.
  相似文献   
67.
Oh SY  Yoo DI  Shin Y  Kim HC  Kim HY  Chung YS  Park WH  Youk JH 《Carbohydrate research》2005,340(15):2376-2391
Crystalline structures of cellulose (named as Cell 1), NaOH-treated cellulose (Cell 2), and subsequent CO2-treated cellulose (Cell 2-C) were analyzed by wide-angle X-ray diffraction and FTIR spectroscopy. Transformation from cellulose I to cellulose II was observed by X-ray diffraction for Cell 2 treated with 15-20 wt% NaOH. Subsequent treatment with CO2 also transformed the Cell 2-C treated with 5-10 wt% NaOH. Many of the FTIR bands including 2901, 1431, 1282, 1236, 1202, 1165, 1032, and 897 cm(-1) were shifted to higher wave number (by 2-13 cm(-1)). However, the bands at 3352, 1373, and 983 cm(-1) were shifted to lower wave number (by 3-95 cm(-1)). In contrast to the bands at 1337, 1114, and 1058 cm(-1), the absorbances measured at 1263, 993, 897, and 668 cm(-1) were increased. The FTIR spectra of hydrogen-bonded OH stretching vibrations at around 3352 cm(-1) were resolved into three bands for cellulose I and four bands for cellulose II, assuming that all the vibration modes follow Gaussian distribution. The bands of 1 (3518 cm(-1)), 2 (3349 cm(-1)), and 3 (3195 cm(-1)) were related to the sum of valence vibration of an H-bonded OH group and an intramolecular hydrogen bond of 2-OH ...O-6, intramolecular hydrogen bond of 3-OH...O-5 and the intermolecular hydrogen bond of 6-O...HO-3', respectively. Compared with the bands of cellulose I, a new band of 4 (3115 cm(-1)) related to intermolecular hydrogen bond of 2-OH...O-2' and/or intermolecular hydrogen bond of 6-OH...O-2' in cellulose II appeared. The crystallinity index (CI) was obtained by X-ray diffraction [CI(XD)] and FTIR spectroscopy [CI(IR)]. Including absorbance ratios such as A1431,1419/A897,894 and A1263/A1202,1200, the CI(IR) was evaluated by the absorbance ratios using all the characteristic absorbances of cellulose. The CI(XD) was calculated by the method of Jayme and Knolle. In addition, X-ray diffraction curves, with and without amorphous halo correction, were resolved into portions of cellulose I and cellulose II lattice. From the ratio of the peak area, that is, peak area of cellulose I (or cellulose II)/total peak area, CI(XD) were divided into CI(XD-CI) for cellulose I and CI(XD-CII) for cellulose II. The correlation between CI(XD-CI) (or CI(XD-CII)) and CI(IR) was evaluated, and the bands at 2901 (2802), 1373 (1376), 897 (894), 1263, 668 cm(-1) were good for the internal standard (or denominator) of CI(IR), which increased the correlation coefficient. Both fraction of the absorbances showing peak shift were assigned as the alternate components of CI(IR). The crystallite size was decreased to constant value for Cell 2 treated at >or= 15 wt% NaOH. The crystallite size of Cell 2-C (cellulose II) was smaller than that of Cell 2 (cellulose I) treated at 5-10 wt% NaOH. But the crystallite size of Cell 2-C (cellulose II) was larger than that of Cell 2 (cellulose II) treated at 15-20 wt% NaOH.  相似文献   
68.
Leukotriene E4 (LTE4) that plays a key role in airway inflammation is expressed on platelets and eosinophils. We investigated whether blocking of the P2Y12 receptor can suppress eosinophilic inflammation in a mouse model of asthma because platelets and eosinophils share this receptor to be activated. BALB/c mice were sensitized by intraperitoneal injection of ovalbumin (OVA), followed by OVA nebulization. On each challenge day, clopidogrel, a P2Y12 antagonist was administered 30 min. before each challenge. Forty‐eight hours after the last OVA challenge, mice were assessed for airway hyperresponsiveness (AHR), cell composition and cytokine levels, including chemokine ligand 5 (CCL5), in bronchoalveolar lavage (BAL) fluid. EOL cells were treated with LTE4, with or without clopidogrel treatment, and intracellular and extracellular eosinophil cationic protein (ECP) expressions were measured to find the inhibiting function of P2Y12 antagonist on eosinophilic activation. The levels of P2Y12 expression were increased markedly in the lung homogenates of OVA‐sensitized and ‐challenged mice after platelet depletion. Administration of clopidogrel decreased AHR and the number of airway inflammatory cells, including eosinophils, in BAL fluid following OVA challenge. These results were associated with decreased levels of Th2 cytokines and CCL5. Histological examination showed that inflammatory cells as well as mucus‐containing goblet cells were reduced in clopidogrel‐administered mice compared to vehicle‐treated mice. Clopidogrel inhibited extracellular ECP secretion after LTE4 stimulation in EOL‐1 cells. Clopidogrel could prevent development of AHR and airway inflammation in a mouse model of asthma. P2Y12 can be a novel therapeutic target to the suppression of eosinophils in asthma.  相似文献   
69.
The tomato bZIP2-encoding gene was inserted into the Nicotiana benthamiana genome using Agrobacterium-mediated transformation to characterize resistance to oxidative stress and two herbicides, glyphosate and paraquat. We produced transgenic tobacco plants using the LebZIP2 gene, which were then utilized to examine salt stress and herbicide resistance through oxidative mechanisms. Transgenic LebZIP2-overexpressing plants were examined using specific primers for selection marker genes (PCR using genomic DNA) and target genes (RT-PCR). Based on microscopic examination, we observed an increase in leaf thickness and cell number in transgenic plants. The electrolyte leakage of leaves suggested that LebZIP2-overexpressing lines were weak tolerant to NaCl stress and resistant to methyl viologen. During our analysis, transgenic lines were exposed to different herbicides. Transgenic plants showed an increased tolerance based on visual injury, as well as an increased biomass. Based on these results, the LebZIP2 gene may be involved in oxidative stress tolerance and cell development in plants.  相似文献   
70.
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