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61.
Kołodziej Barbara Kochan Ewa Kazimierczak Jerzy Chmiel Aleksander 《Plant Growth Regulation》2006,48(1):13-19
American ginseng (Panax quinquefolium L.) is a perennial medicinal herb originally grown in Canada and USA, and recently also in China, Australia, Holland and
Poland. Several commercial preparations are produced from ginseng roots, that are known for their antifatigue, antitumor,
antistress and immune system stimulating functions. The medicinal properties are due mainly to the active components – ginsenosides.
In this work, the results of field cultivation experiments are presented that examine the effects of foliar application of
several growth regulators on quality parameters and ginsenoside content of P. quinuefolium roots. The growth regulators tested, i.e., kinetin, daminozide, mixture of gibberellic acid (GA3) with potassium salt of α-naphthalene acetic acid (kNAA) and new preparation – IPO-1 – benzimidazole derivative (obtained
from the Institute of Organic Industry in Warsaw – at present during the process of patent), were applied at a concentration
of 100 or 200 mg l−1 in the middle of June in the 2nd year of vegetation. After 4 years of cultivation, the roots were dug up and dried, and subsequently
the quantitative analysis of individual saponins (Rb1, Rb2, Rc, Rd, Re, Rg1) by HPLC was performed. Growth regulators significantly affected quality parameters, morphological features and accumulation
of individual and total ginsenosides in ginseng roots. Regardless of doses, the plant roots treated with growth regulators
had a higher content of total ginsenosides in comparison to the control. The growth regulators also affected individual ginsenosides
level and narrowed the ratio of Rb:Rg group. The application of kinetin, daminozide and benzimidazole derivative for foliar spray during 2nd year of American ginseng
vegetation caused a significant increase in air dry weight of roots and aboveground parts whereas the mixture of GA3 and kNAA showed a decreasing effect. An increase of roots size was observed using higher doses (200 mg l−1) of kinetin and daminozide while a decreasing tendency appeared with the application of the other preparations. 相似文献
62.
Do Geum-Sook Seo Bong-Bo Ko Jong-Min Lee Seon-Hee Pak Jae-Hong Kim In-Sun Song Seung-Dal 《Plant Cell, Tissue and Organ Culture》1999,57(2):113-119
The effects of basal media and growth regulators on callus initiation and shoot regeneration have been investigated in wild
Allium tuberosum (2n = 4x = 32). Callus initiation was greatest from flower bud explants cultured on MS medium supplemented
with 2,4-D and BA at 1 mg l−1 each. Maximum number of shoots was obtained from callus grown on MS medium supplemented with NAA and BA at 0.2 and 2 mg l−1, respectively. The chromosome analysis of regenerants derived from callus revealed variation in ploidy, such as 2n = 28,
29, 30, 31, 33 as well as normal tetraploid. During the culture period for two generations, one aneuploid regenerant with
2n = 30 (named At30) showed better viability and growth than tetraploid plants and other aneuploid variants. In a karyotypic
analysis of At30, the chromosomal positions of 5S and 18S-5.8S-26S rDNA were physically mapped by fluorescent in situ hybridization
and compared to chromosomes of wild type A. tuberosum. Both wild type A. tuberosum and At30 exhibited two sets of 5S rDNA
sites, one on the proximal position of the short arm of chromosome 3, and the other on the intercalary region on the long
arm of chromosome 6. There was one 18S-5.8S-26S rDNA site in the secondary constriction including flanking short chromosomal
segments of satellite and terminal regions on the short arm of chromosome 8 in wild type A. tuberosum. However, At30 showed
only three labelled chromosome 8 indicating that this was one of the lost chromosomes of At30.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
63.
M Tartas P Bouyé A Ko?tka V Jaquinandi L Tan J L Saumet P Abraham 《Journal of applied physiology》2005,99(4):1538-1544
Assumed to rely on an axon reflex, the current-induced vasodilation (CIV) interferes with the microvascular response to iontophoretic drug delivery. Mechanisms resulting in CIV are likely different at the anode and at the cathode. While studies have been conducted to understand anodal CIV, little information is available on cathodal CIV. The present study investigates CIV observed following 0.1-mA cathodal applications on forearms of healthy volunteers and the possible mechanisms involved. Results are expressed in percentage of the cutaneous heat-induced maximal vascular conductance [%MVC (means +/- SE)]. 1) The amplitude of CIV was proportional to the duration of cathodal currents for periods of <1 min: r = 0.99. 2) Two current applications of 10 s, with 10-min interstimulation interval, induced a higher peak value of CIV (79.1 +/- 8.6% MVC) than the one obtained with all-at-once 20-s current application (39.5 +/- 4.3% MVC, P < 0.05). This amplified vascular response due to segmental application was observed for all tested interstimulation intervals (up to 40 min). 3) Two hours and 3 days following pretreatment with 1-g oral aspirin, the CIV observed following cathodal application, as well as the difference of cathodal CIV amplitude between all-at-once and segmented applications, were reduced. These findings suggest a role of prostaglandins, not only released from endothelial or smooth muscle cells, as direct vasodilator and/or as a sensitizer. Thus aspirin pretreatment could be used to decrease CIV resulting from all-at-once and repeated cathodal application and facilitate the study of the specific vascular effect induced by the drug delivered. 相似文献
64.
D. J. Wolff Karen M. Gustashaw Vickie Zurcher Lara Ko Wendy White Lester Weiss Daniel L. Van Dyke Stuart Schwartz Huntington F. Willard 《Human genetics》1997,100(2):256-262
High resolution cytogenetics, microsatellite marker analyses, and fluorescence in situ hybridization were used to define
Xq deletions encompassing the fragile X gene, FMR1, detected in individuals from two unrelated families. In Family 1, a 19-year-old
male had facial features consistent with fragile X syndrome; however, his profound mental and growth retardation, small testes,
and lover limb skeletal defects and contractures demonstrated a more severe phenotype, suggestive of a contiguous gene syndrome.
A cytogenetic deletion including Xq26.3–q27.3 was observed in the proband, his phenotypically normal mother, and his learning-disabled
non-dysmorphic sister. Methylation analyses at the FMR1 and androgen receptor loci indicated that the deleted X was inactive
in > 95% of his mother’s white blood cells and 80–85% of the sister’s leukocytes. The proximal breakpoint for the deletion
was approximately 10 Mb centromeric to FMR1, and the distal breakpoint mapped 1 Mb distal to FMR1. This deletion, encompassing
∼13 Mb of DNA, is the largest deletion including FMR1 reported to date. In the second family, a slightly smaller deletion
was detected. A female with moderate to severe mental retardation, seizures, and hypothyroidism, had a de novo cytogenetic
deletion extending from Xq26.3 to q27.3, which removed ∼12 Mb of DNA around the FMR1 gene. Cytogenetic and molecular data
revealed that ∼50% of her white blood cells contained an active deleted X. These findings indicate that males with deletions
including Xq26.3–q27.3 may exhibit a more severe phenotype than typical fragile X males, and females with similar deletions
may have an abnormal phenotype if the deleted X remains active in a significant proportion of the cells. Thus, important genes
for intellectual and neurological development, in addition to FMR1, may reside in Xq26.3–q27.3. One candidate gene in this
region, SOX3, is thought to be involved in neuronal development and its loss may partly explain the more severe phenotypes
of our patients.
Received: 19 December 1996 / Accepted: 13 March 1997 相似文献
65.
Ahtesham Hussain Mukesh Kumar Yadav Shambhunath Bose Jing-Hua Wang Dongwoo Lim Yun-Kyung Song Seong-Gyu Ko Hojun Kim 《PloS one》2016,11(11)
BackgroundObesity has become a major global health challenge due to its increasing prevalence, and the associated health risk. It is the main cause of various metabolic diseases including diabetes, hypertension, cardiovascular disease, stroke and certain forms of cancer.
Methods and Results
In the present study we evaluated the anti-obesity property of Daesiho-tang (DSHT), an herbal medicine, using high fat diet (HFD)-induced obese mice as a model. Our results showed that DSHT ameliorated body weight gain, decreased total body fat, regulated expression of leptin and adiponectin genes of adipose tissue and exerted an anti-diabetic effect by attenuating fasting glucose level and serum insulin level in HFD-fed animals. In addition, DSHT-treatment significantly reduced total cholesterol (TC), triglycerides (TG) and increased high density lipoprotein-cholesterol (HDL), glutamic pyruvic transaminase (GPT) and glutamic oxaloacetic transaminase (GOT) levels in serum and reduced deposition of fat droplets in liver. DSHT treatment resulted in significantly increased relative abundance of bacteria including Bacteroidetes, Bacteroidetes/Firmicutes ratio, Akkermansia Bifidobacterium., Lactobacillus, and decreased the level of Firmicutes. Using RT2 profiler PCR array, 39 (46%) genes were found to be differentially expressed in HFD-fed mice compared to normal control. However, normal gene expressions were restored in 36 (92%) genes of HFD-fed mice, when co-exposed to DSHT.Conclusion/Major Findings
The results of this study demonstrated that DSHT is an effective herbal formulation in attenuation of obesity in HFD-fed mice through alteration of gene expressions and modulation of intestinal microbiota. 相似文献66.
Peeters A Fraisl P van den Berg S Ver Loren van Themaat E Van Kampen A Rider MH Takemori H van Dijk KW Van Veldhoven PP Carmeliet P Baes M 《The Journal of biological chemistry》2011,286(49):42162-42179
Hepatic peroxisomes are essential for lipid conversions that include the formation of mature conjugated bile acids, the degradation of branched chain fatty acids, and the synthesis of docosahexaenoic acid. Through unresolved mechanisms, deletion of functional peroxisomes from mouse hepatocytes (L-Pex5(-/-) mice) causes severe structural and functional abnormalities at the inner mitochondrial membrane. We now demonstrate that the peroxisomal and mitochondrial anomalies trigger energy deficits, as shown by increased AMP/ATP and decreased NAD(+)/NADH ratios. This causes suppression of gluconeogenesis and glycogen synthesis and up-regulation of glycolysis. As a consequence, L-Pex5(-/-) mice combust more carbohydrates resulting in lower body weights despite increased food intake. The perturbation of carbohydrate metabolism does not require a long term adaptation to the absence of functional peroxisomes as similar metabolic changes were also rapidly induced by acute elimination of Pex5 via adenoviral administration of Cre. Despite its marked activation, peroxisome proliferator-activated receptor α (PPARα) was not causally involved in these metabolic perturbations, because all abnormalities still manifested when peroxisomes were eliminated in a peroxisome proliferator-activated receptor α null background. Instead, AMP-activated kinase activation was responsible for the down-regulation of glycogen synthesis and induction of glycolysis. Remarkably, PGC-1α was suppressed despite AMP-activated kinase activation, a paradigm not previously reported, and they jointly contributed to impaired gluconeogenesis. In conclusion, lack of functional peroxisomes from hepatocytes results in marked disturbances of carbohydrate homeostasis, which are consistent with adaptations to an energy deficit. Because this is primarily due to impaired mitochondrial ATP production, these L-Pex5-deficient livers can also be considered as a model for secondary mitochondrial hepatopathies. 相似文献
67.
Chen Y Ip SP Ko KM Poon TC Ng EW Lai PB Mao QQ Xian YF Che CT 《Journal of proteome research》2011,10(1):299-304
To identify key proteins involved in the hepatoprotection afforded by schisandrin B (Sch B), we used a proteomic approach to screen proteins that were specifically regulated by Sch B in mouse livers and to investigate the role of the proteins in hepatoprotection. Thirteen proteins were specifically activated or suppressed by Sch B treatment. Among the 13 proteins, Raf kinase inhibitor protein (RKIP) was postulated to be the key regulator involved in the development of hepatotoxin-induced cellular damage. The results indicated that the downregulation of RKIP by antisense RKIP vector transfection led to the activation of the Raf-1/MEK/ERK signaling pathway, as evidenced by increases in the level of MEK/ERK phosphorylation and the level of nuclear factor erythroid 2-related factor 2 in the nucleus. The signaling effect produced by RKIP downregulation resembled that triggered by Sch B, wherein both treatments resulted in a decrease in the extent of carbon tetrachloride-induced apoptotic cell death in AML12 hepatocytes. Overexpression of RKIP by the sense RKIP transfection vector or the inhibition of MEK kinase by PD98059 was able to abrogate the cytoprotective effect of Sch B in the hepatocytes. The results indicate that Sch B triggers the Raf/MEK/ERK signaling pathway, presumably by downregulating RKIP, thereby protecting against carbon tetrachloride-induced cytotoxicity. 相似文献
68.
Eui Jeong Doh Ningjie Yang Myung-Guk Ji Guem-San Lee Young-Sung Ju Je Hyun Lee Byong Seob Ko Seung-Eun Oh 《Genes & genomics.》2011,33(6):711-719
‘Kalopanacis Cortex’ (KC) is an important medicinal material prescribed in Korea for the treatment of various ailments such as paralysis, arthritis, and rheumatism. In Korea, KC is defined as the dried stem bark of Kalopanax pictus. However, the stem barks of Zanthoxylum ailanthoides and Erythrina plants such as E. variegata have also been described as KC and prescribed for the same diseases. Since the pharmacological activities and contents of compounds isolated from the stem barks of these KC plants are obviously different, KC from K. pictus should be clearly discriminated from other stem bark in the best interest of public health. This study sequenced the internal transcribed spacers (ITS) of 52 samples of the KC or KC plants collected from Korea, China, and Vietnam. On the basis of different nucleotide sequences of specific ITS regions among the KC plants, the primer set KP F2/KC R1 was designed to amplify a 398-bp DNA marker for discriminating K. pictus from its varieties and from other KC plants. This primer set, along with the primer sets ZR F1/ZR R4, KP F1/EV R2, and KPF1/KC R1, was successfully amplified with the DNA markers of the Z. ailanthoides, E. variegata, and K. pictus taxa, respectively. The multiplex polymerase chain reaction method developed here not only discriminates the stem bark of K. pictus from stem barks of other KC plants but also identifies KC plants that supply KC in a single process. 相似文献
69.
Choy HA Kelley MM Croda J Matsunaga J Babbitt JT Ko AI Picardeau M Haake DA 《PloS one》2011,6(2):e16879
Leptospirosis is a potentially fatal zoonotic disease in humans and animals caused by pathogenic spirochetes, such as Leptospira interrogans. The mode of transmission is commonly limited to the exposure of mucous membrane or damaged skin to water contaminated by leptospires shed in the urine of carriers, such as rats. Infection occurs during seasonal flooding of impoverished tropical urban habitats with large rat populations, but also during recreational activity in open water, suggesting it is very efficient. LigA and LigB are surface localized proteins in pathogenic Leptospira strains with properties that could facilitate the infection of damaged skin. Their expression is rapidly induced by the increase in osmolarity encountered by leptospires upon transition from water to host. In addition, the immunoglobulin-like repeats of the Lig proteins bind proteins that mediate attachment to host tissue, such as fibronectin, fibrinogen, collagens, laminin, and elastin, some of which are important in cutaneous wound healing and repair. Hemostasis is critical in a fresh injury, where fibrinogen from damaged vasculature mediates coagulation. We show that fibrinogen binding by recombinant LigB inhibits fibrin formation, which could aid leptospiral entry into the circulation, dissemination, and further infection by impairing healing. LigB also binds fibroblast fibronectin and type III collagen, two proteins prevalent in wound repair, thus potentially enhancing leptospiral adhesion to skin openings. LigA or LigB expression by transformation of a nonpathogenic saprophyte, L. biflexa, enhances bacterial adhesion to fibrinogen. Our results suggest that by binding homeostatic proteins found in cutaneous wounds, LigB could facilitate leptospirosis transmission. Both fibronectin and fibrinogen binding have been mapped to an overlapping domain in LigB comprising repeats 9-11, with repeat 11 possibly enhancing binding by a conformational effect. Leptospirosis patient antibodies react with the LigB domain, suggesting applications in diagnosis and vaccines that are currently limited by the strain-specific leptospiral lipopolysaccharide coats. 相似文献
70.
Puligundla P Smogrovicova D Obulam VS Ko S 《Journal of industrial microbiology & biotechnology》2011,38(9):1133-1144
There have been numerous developments in ethanol fermentation technology since the beginning of the new millennium as ethanol
has become an immediate viable alternative to fast-depleting crude reserves as well as increasing concerns over environmental
pollution. Nowadays, although most research efforts are focused on the conversion of cheap cellulosic substrates to ethanol,
methods that are cost-competitive with gasoline production are still lacking. At the same time, the ethanol industry has engaged
in implementing potential energy-saving, productivity and efficiency-maximizing technologies in existing production methods
to become more viable. Very high gravity (VHG) fermentation is an emerging, versatile one among such technologies offering
great savings in process water and energy requirements through fermentation of higher concentrations of sugar substrate and,
therefore, increased final ethanol concentration in the medium. The technology also allows increased fermentation efficiency,
without major alterations to existing facilities, by efficient utilization of fermentor space and elimination of known losses.
This comprehensive research update on VHG technology is presented in two main sections, namely VHG brewing, wherein the effects
of nutrients supplementation, yeast pitching rate, flavour compound synthesis and foam stability under increased wort gravities
are discussed; and VHG bioethanol fermentation studies. In the latter section, aspects related to the role of osmoprotectants
and nutrients in yeast stress reduction, substrates utilized/tested so far, including saccharide (glucose, sucrose, molasses,
etc.) and starchy materials (wheat, corn, barley, oats, etc.), and mash viscosity issues in VHG bioethanol production are
detailed. Thereafter, topics common to both areas such as process optimization studies, mutants and gene level studies, immobilized
yeast applications, temperature effect, reserve carbohydrates profile in yeast, and economic aspects are discussed and future
prospects are summarized. 相似文献