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61.
Cho EJ Hwang HJ Kim SW Oh JY Baek YM Choi JW Bae SH Yun JW 《Applied microbiology and biotechnology》2007,75(6):1257-1265
The anti-diabetic activities of the exopolysaccharides (EPS) produced by submerged mycelial culture of two different mushrooms,
Tremella fuciformis and Phellinus baumii, in ob/ob mice were investigated. All the animals were randomly divided into three groups with seven animals in each group: The control
group received 0.9% NaCl solution; the diabetic groups were treated with EPS from T. fuciformis (Tf EPS) and P. baumii (Pb EPS) at the level of 200 mg/kg body weight using an oral zoned daily for 52 days. The plasma glucose levels in the EPS-fed
mice were substantially reduced by about 52% (Tf EPS) and 32% (Pb EPS), respectively, as compared to control mice. The results
of oral glucose tolerance test (OGTT) revealed that both EPS-fed groups significantly increased the glucose disposal after
52 days of EPS treatments. Furthermore, higher food efficiency ratios and reduced blood triglyceride levels were observed
in the EPS-treated groups. Because peroxisome proliferator-activated receptor gamma (PPAR-γ) is indeed a key regulator of
insulin action, we investigated the expression pattern of adipose tissue PPAR-γ messenger RNA (mRNA) and plasma levels of
PPAR-γ. It was revealed that PPAR-γ was significantly activated in response to EPS treatments. The results suggested that
both EPS exhibited considerable hypoglycemic effect and improved insulin sensitivity possibly through regulating PPAR-γ-mediated
lipid metabolism. Our results indicated that two mushroom-derived EPS might be developed as potential oral hypoglycemic agents
or functional foods for the management of non-insulin-dependent diabetes mellitus. 相似文献
62.
Wiley PR Tosi P Evrard A Lovegrove A Jones HD Shewry PR 《Plant molecular biology》2007,65(1-2):125-136
Increasing its root to shoot ratio is a plant strategy for restoring water homeostasis in response to the long-term imposition
of mild water stress. In addition to its important role in diverse fundamental processes, indole-3-acetic acid (IAA) is involved
in root growth and development. Recent extensive characterizations of the YUCCA gene family in Arabidopsis and rice have elucidated that member’s function in a tryptophan-dependent IAA biosynthetic pathway. Through forward- and
reverse-genetics screening, we have isolated Tos17 and T-DNA insertional rice mutants in a CONSTITUTIVELY WILTED1 (COW1) gene, which encodes a new member of the YUCCA protein family. Homozygous plants with either a Tos17 or T-DNA-inserted allele of OsCOW1 exhibit phenotypes of rolled leaves, reduced leaf widths, and lower root to shoot ratios. These phenotypes are evident in
seedlings as early as 7–10 d after germination, and remain until maturity. When oscow1 seedlings are grown under low-intensity light and high relative humidity, the rolled-leaf phenotype is greatly alleviated.
For comparison, in such conditions, the transpiration rate for WT leaves decreases approx. 5- to 10-fold, implying that this
mutant trait results from wilting rather than being a morphogenic defect. Furthermore, a lower turgor potential and transpiration
rate in their mature leaves indicates that oscow1 plants are water-deficient, due to insufficient water uptake that possibly stems from that diminished root to shoot ratio.
Thus, our observations suggest that OsCOW1-mediated IAA biosynthesis plays an important role in maintaining root to shoot ratios and, in turn, affects water homeostasis
in rice. 相似文献
63.
64.
Efficiency Enhancement of Organic Solar Cells Using Hydrophobic Antireflective Inverted Moth‐Eye Nanopatterned PDMS Films 下载免费PDF全文
Jung Woo Leem Sehwan Kim Soo Hyun Lee John A. Rogers Eunkyoung Kim Jae Su Yu 《Liver Transplantation》2014,4(8)
Poly‐dimethylsiloxane (PDMS) films with 2D periodic inverted moth‐eye nanopatterns on one surface are implemented as antireflection (AR) layers on a glass substrate for efficient light capture in encapsulated organic solar cells (OSCs). The inverted moth‐eye nanopatterned PDMS (IMN PDMS) films are fabricated by a soft imprint lithographic method using conical subwavelength grating patterns formed by laser interference lithography/dry etching. Their optical characteristics, together with theoretical analysis using rigorous coupled‐wave analysis simulation, and wetting behaviors are investigated. For a period of 380 nm, IMN PDMS films laminated on glass substrates exhibit a hydrophobic surface with a water contact angle (θCA) of ≈120° and solar weighted transmittance (SWT) of ≈94.2%, both significantly higher than those (θCA≈ 36° and SWT ≈ 90.3%) of bare glass substrates. By employing IMN PDMS films with a period of 380 nm on glass substrates for OSCs, an enhanced power conversion efficiency (PCE) of 6.19% is obtained mainly due to the increased short‐circuit current density (Jsc) of 19.74 mA cm‐2 compared to the OSCs with the bare glass substrates (PCE = 5.16% and Jsc = 17.25 mA cm‐2). For the OSCs, the device stability is also studied. 相似文献
65.
Kyung-Ha Ryu So-Yeon Kim Ye-Ryung Kim So-Youn Woo Sun Hee Sung Han Su Kim Sung-Chul Jung Inho Jo Joo-Won Park 《Experimental cell research》2014
Acute liver failure, the fatal deterioration of liver function, is the most common indication for emergency liver transplantation, and drug-induced liver injury and viral hepatitis are frequent in young adults. Stem cell therapy has come into the limelight as a potential therapeutic approach for various diseases, including liver failure and cirrhosis. In this study, we investigated therapeutic effects of tonsil-derived mesenchymal stem cells (T-MSCs) in concanavalin A (ConA)- and acetaminophen-induced acute liver injury. ConA-induced hepatitis resembles viral and immune-mediated hepatic injury, and acetaminophen overdose is the most frequent cause of acute liver failure in the United States and Europe. Intravenous administration of T-MSCs significantly reduced ConA-induced hepatic toxicity, but not acetaminophen-induced liver injury, affirming the immunoregulatory capacity of T-MSCs. T-MSCs were successfully recruited to damaged liver and suppressed inflammatory cytokine secretion. T-MSCs expressed high levels of galectin-1 and -3, and galectin-1 knockdown which partially diminished interleukin-2 and tumor necrosis factor α secretion from cultured T-cells. Galectin-1 knockdown in T-MSCs also reversed the protective effect of T-MSCs on ConA-induced hepatitis. These results suggest that galectin-1 plays an important role in immunoregulation of T-MSCs, which contributes to their protective effect in immune-mediated hepatitis. Further, suppression of T-cell activation by frozen and thawed T-MSCs implies great potential of T-MSC banking for clinical utilization in immune-mediated disease. 相似文献
66.
Seong Jin Jeong Han Sol Lee Jeong Keun Lee Jin Woo Jeong Sang Cheol Lee Jeong Hyun Kim Sung Kyu Hong Seok-Soo Byun Sang Eun Lee 《PloS one》2014,9(11)
Objectives
Mid-urethral sling (MUS) surgery for the treatment of urinary incontinence has been widespread since the introduction of tension-free vaginal tape in the mid-1990s. The majority of studies with short-term follow-up <2 years found no differences in the surgical outcomes according to body mass index (BMI). However, considering the chronic influence of obesity on pelvic floor musculature, it is cautiously speculated that higher BMI could increase stress on pelvic floor and sub-urethral tape, possibly decreasing the long-term success rate in the obese population. We aimed to compare the long-term effects of BMI on the outcomes of MUS between women with retropubic and transobturator approaches.Methods
We performed a retrospective analysis on 243 consecutive women who received MUS and were followed up for ≥36 months. The influence of BMI on the success rates was separately estimated and the factors for treatment failure were examined using logistic regression in either approach.Results
The mean follow-up was 58.4 months, and 30.5% were normal weight, 51.0% overweight, and 18.5% obese. Patients received either the retropubic (30.5%) or transobturator (69.5%) approach. The success rates (%) under the transobturator approach differed according to the BMI groups (94.3, 88.6, and 78.6, respectively; P = 0.037) while those under the retropubic approach were not different according to the BMI groups. However, in multivariate models, only the presence of preoperative mixed urinary incontinence (MUI) was proven to be the risk factor for treatment failure in the transobturator approach (OR 6.39, P = 0.003). The percent of subjects with MUI was higher in obese women than in non-obese women with the transobturator approach.Conclusions
BMI was not independently associated with failures in either approach. Higher success rates in women with lower BMI in the transobturator approach were attributed to the lower percent of preoperative MUI in those with lower BMI. 相似文献67.
Pfaeffle HJ Fischer KJ Srinivasa A Manson T Woo SL Tomaino M 《Journal of biomechanical engineering》2006,128(5):725-732
Fiber network theory was developed to describe cloth, a thin material with strength in the fiber directions. The interosseous ligament (IOL) of the forearm is a broad, thin ligament with highly aligned fibers. The objectives of this study were to develop a model of the stress and strain distributions in the IOL, based on fiber network theory, to compare the strains from the model with the experimentally measured strains, and to evaluate the force distribution across the ligament fibers from the model. The geometries of the radius, ulna, and IOL were reconstructed from CT scans. Position and orientation of IOL insertion sites and force in the IOL were measured during a forearm compression experiment in pronation, neutral rotation, and supination. An optical image-based technique was used to directly measure strain in two regions of the IOL in neutral rotation. For the network model, the IOL was represented as a parametric ruled three-dimensional surface, with rulings along local fiber directions. Fiber strains were calculated from the deformation field, and fiber stresses were calculated from the strains using average IOL tensile properties from a previous study. The in situ strain in the IOL was assumed uniform and was calculated so that the net force predicted by the network model in neutral rotation matched the experimental result. The net force in the IOL was comparable to experimental results in supination and pronation. The model predicted higher stress and strain in fibers near the elbow in neutral rotation, and higher stresses in fibers near the wrist in supination. Strains in neutral forearm rotation followed the same trends as those measured experimentally. In this study, a model of stress and strain in the IOL utilizing fiber network theory was successfully implemented. The model illustrates variations in the stress and strain distribution in the IOL. This model can be used to show surgeons how different fibers are taut in different forearm rotation positions-this information is important for understanding the biomechanical role of the IOL and for planning an IOL reconstruction. 相似文献
68.
J Li R C Eisensmith T Wang W H Lo S Z Huang Y T Zeng L F Yuan S R Liu S L Woo 《Genomics》1992,13(3):894-895
Three novel missense mutations have been identified in the phenylalanine hydroxylase (PAH) genes of Chinese individuals afflicted with various degrees of phenylketonuria (PKU). A T-to-C transition was observed in exon 5 of the gene, resulting in the substitution of Phe161 by Ser161. Two substitutions, G-to-T and T-to-G, were observed in exon 7, resulting in the substitution of Gly247 by Val247 and Leu255 by Val255, respectively. Expression analysis demonstrated that these mutant proteins produced between 0 and 15% of normal PAH enzyme activity. Population screening of a Chinese sample population indicates that these mutations are quite rare, together accounting for only about 4% of all PKU alleles among the Chinese. The P161S and G247V mutations were each present on a single PAH RFLP haplotype 4 chromosome in patients form Northern China, while the L255V mutation was present on chromosomes of both haplotypes 18 and 21 in patients from Southern China. These results suggest that the remaining 30% of uncharacterized PKU alleles in the Chinese population may bear a large number of relatively rare PAH mutations. 相似文献
69.
70.
Cytotechnology - Bone mass is regulated by osteoblast-mediated bone formation and osteoclast-mediated bone resorption. Osteoporosis is a bone metabolism disorder in which bone mass decreases due to... 相似文献