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1.
Cordyceps sinensis is widely used as a traditional medicine for treatment of a wide variety of diseases or to maintain health. The immunomodulatory
activity of polysaccharides prepared from submerged cultured C. sinensis BCRC36421 was investigated in human peripheral blood. Results demonstrated that Fr. A (exo-polysaccharides, 0.025 ∼ 0.1 mg/ml)
induced the production of tumor necrosis factor alpha (TNF-α), interleukin (IL)-6, and IL-10 dose-dependently. Fr. A, as low
as 0.025 mg/ml, could significantly augment surface expression of CD11b in monocytes and polymorphonuclear neutrophils. Functional
assay revealed that Fr. A (0.05 mg/ml) also elevated phagocytosis in monocytes and PMN. On the other hand, Fr. B (intracellular
polysaccharides) only moderately induced TNF-α release, CD11b expression, and phagocytosis at the same concentrations. Our
results indicate that the immunomodulatory components of submerged cultured C. sinensis mainly reside in the culture filtrate. 相似文献
2.
Effect of red mold rice on antifatigue and exercise-related changes in lipid peroxidation in endurance exercise 总被引:3,自引:0,他引:3
This study evaluated the effect of red mold rice supplementation on antifatigue and exercise-related changes in lipid peroxidation
of male adult Wistar rats through swimming exercise. Thirty 16-week-old rats were studied by dividing them into three groups
(ten for each group). Other than the control group (CD), the other two groups were divided into a high-dose (HD) treatment
group (5 g red mold rice/kg body weight for the HD group), and a low-dose (LD) group (1 g red mold rice/kg body weight for
the LD group). Swimming endurance tests were conducted after 28 days of red mold rice supplementation, and the result showed
that the treatment group showed a higher exercise time (CD, 78.0±6.4; LD, 104.2±9.6; and HD, 129.4±10.9 min; p<0.05) and a higher blood glucose concentration (CD, 76.67±8.08; LD, 111.34±8.50; and HD, 117.67±11.06 mg/dl; p<0.05) than the CD. Moreover, the blood lactate (CD, 45.00±0.90; LD, 31.41±1.80; and HD, 28.89±1.62 mg/dl; p<0.05), blood urea nitrogen (CD, 21.87±0.75; LD, 20.33±0.83; and HD, 20.53±1.09 mg/dl; p<0.05), and hemoglobin (CD, 14.20±0.21; LD, 13.70±0.55; and HD, 13.28±0.35 g/dl; p<0.05) were also significantly lower than those of the CD. Besides, the result suggested that the red mold rice supplementation
may decrease the contribution of exercise-induced oxidative stress and improve the physiological condition of the rats. 相似文献
3.
Kuo Wu-Nan Kreahling Jenny M. Shanbhag Vinayak P. Shanbhag Pretti P. Mewar Madhvi 《Molecular and cellular biochemistry》2000,214(1):121-129
Various proteins/enzymes obtained commercially were tested for the presence of endogenously nitrated tyrosine by Western blot analysis omitting reducing agent in the step of SDS-PAGE. Histones II-S and VIII-S, IgG, cAMP-dependent protein kinase (PKA), phosphorylase b, and phosphorylase kinase exhibited strong immunoreactive bands. Histone VI-S, glycogen synthase, lactate dehydrogenase, actin, thyroglobulin, and macroglobulin exhibited moderate immunoreactivity. Histone III-S, casein, acetyl cholinesterase, DNase I, and lipase had only traceable immunoreactivity. Whereas histone VII-S, pyruvate kinase, trypsin, pepsin, chymotrypsin, protease IV, and protease XIII, and glutathione S-transferase lacked immunoreactivity. A variation of immunoreactivity between hypertensive and normaltensive rat hearts was found in the histone-agarose fractions of crude extracts. Additionally, nitrotyrosine immunoreactivity was observed in non-mammalian organisms including Eschericia coli, Saccharomyces cerevisiae and Triticum vulgaris. Upon the treatment of 15 M peroxynitrite (PN), strong oxidant derived from nitric oxide (NO), the apparent Km of PKA for cAMP increased from approximately 10-8 to 10-6 M. The results imply that the varied nitration of tyrosine residues in proteins/enzymes may occur as a post-translational modification in vivo, and such discriminative nitration may be vital in PN/NO-regulated signal transduction cascade. 相似文献
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6.
Raghavan S Yang Z Mosley RT Schleif WA Gabryelski L Olsen DB Stahlhut M Kuo LC Emini EA Chapman KT Tata JR 《Bioorganic & medicinal chemistry letters》2002,12(20):2855-2858
A 1X22X41 combinatorial library or 902 compounds of indinavir analogues was synthesized on the solid support to identify a replacement for the aminoindanol moiety at P2'. 2,6-Dimethyl-4-hydroxy phenol was discovered to be a good replacement for aminoindanol. 相似文献
7.
8.
Kuo CB Wu W Xu X Yang L Chen C Coss D Birdsall B Nasseri D Walker AM 《Cell and tissue research》2002,309(3):429-437
We have investigated the individual roles of unmodified prolactin (U-PRL) and a mimic of phosphorylated PRL (S179D PRL) in mammary development. Recombinant versions of the PRLs were delivered to rats throughout pregnancy at a rate of 6 microg/24 h per rat and to non-pregnant females at a rate of 24 microg/24 h per rat. Measurement of progesterone, corticosterone, and estradiol showed no effect of the administered PRLs on the levels of these other mammotropic hormones. Histological and morphometric analysis showed U-PRL to cause mammary growth, whereas S179D PRL inhibited growth. Molecular analysis demonstrated decreased beta-casein expression in the mammary glands of the U-PRL-treated animals at term and increased beta-casein expression in the mammary glands of the S179D PRL-treated animals. Superior beta-casein gene expression in response to S179D PRL versus U-PRL was confirmed in HC11 cells. We conclude that U-PRL is important for growth, whereas S179D PRL promotes at least one measure of differentiated function in the mammary gland. 相似文献
9.
We investigated finger joint coordination during tapping by characterizing joint kinematics and torques in terms of muscle activation patterns and energy profiles. Six subjects tapped with their index finger on a computer keyswitch as if they were typing on the middle row of a keyboard. Fingertip force, keyswitch position, kinematics of the metacarpophalangeal (MCP) and the proximal and distal interphalangeal (IP) joints, and intramuscular electromyography of intrinsic and extrinsic finger muscles were measured simultaneously. Finger joint torques were calculated based on a closed-form Newton–Euler inverse dynamic model of the finger. During the keystroke, the MCP joint flexed and the IP joints extended before and throughout the loading phase of the contact period, creating a closing reciprocal motion of the finger joints. As the finger lifted, the MCP joint extended and the interphalangeal (IP) joints flexed, creating an opening reciprocal motion. Intrinsic finger muscle and extrinsic flexor activities both began after the initiation of the downward finger movement. The intrinsic finger muscle activity preceded both the IP joint extension and the onset of extrinsic muscle activity. Only extrinsic extensor activity was present as the finger was lifted. While both potential energy and kinetic energy are present and large enough to overcome the work necessary to press the keyswitch, the motor control strategies utilize the muscle forces and joint torques to ensure a successful keystroke. 相似文献
10.