Hasil untuk "hep-lat"

M. Mckee, A. Melton-Celsa, R. Moxley et al.

S. Sassa, O. Sugita, R. Galbraith et al.

Liang Zhou, Xu-dong Wei, Lei Cheng et al.

A. Rabaan, I. Gryllos, J. Tomás et al.

Ying-hua Jin, K. Yoo, Y. Lee et al.

Apoptosis of SK-HEP-1 human hepatoma cells induced by treatment with ginsenoside Rh2 (G-Rh2) is associated with rapid and selective activation of cyclin A-associated cyclin-dependent kinase 2 (Cdk2). Here, we show that in apoptotic cells, the Cdk inhibitory protein p21 WAF1/CIP1 , which is associated with the cyclin A-Cdk2 complex, undergoes selective proteolytic cleavage. In contrast, another Cdk inhibitory protein, p27 KIP1 , which is associated with cyclin A-Cdk2 and cyclin E-Cdk2 complexes, remained unaltered during apoptosis. Ectopic overexpression of p21 WAF1/CIP1 suppressed apoptosis as well as cyclin A-Cdk2 activity induced by treatment of SK-HEP-1 cells with G-Rh2. The suppressive effects of p21 WAF1/CIP1 were much higher in the cells transfected with p21D112N, an expression vector that encodes a p21 WAF1/CIP1 mutant resistant to caspase 3 cleavage. Overexpression of cyclin A in SK-HEP-1 cells dramatically up-regulated cyclin A-Cdk2 activity and accordingly enhances apoptosis induced by treatment with G-Rh2. These up-regulating effects were blocked by coexpression of a dominant negative allele of cdk2. Furthermore, olomoucine, a specific inhibitor of Cdks, also blocked G-Rh2-induced apoptosis. These data suggest that the induction of apoptosis in human hepatoma cells treated with G-Rh2 occurs by a mechanism that involves the activation of cyclin A-Cdk2 by caspase 3-mediated cleavage of p21 WAF1/CIP1 .

T. Baldwin, W. Ward, A. Aitken et al.

Po-Lin Kuo, L. Chiang, Chun‐ching Lin

Xiao-zhong Hu, Ying Xu, Decong Hu et al.

M. Uhl, C. Helma, S. Knasmüller

M.-Y Jung, Hye-Jung Kang, Aree Moon

M. Aubert, Jennifer M O'Toole, J. Blaho

A. S‐Y Leong, R. Sormunen, W. Tsui et al.

Jennifer D. Boddicker, N. Ledeboer, Jennifer R Jagnow et al.

T. Park, T. Park, T. Park et al.

Spurred by the recent complete determination of the weak currents in two-nucleon systems up to $\mathcal{O}{(Q}^{3})$ in heavy-baryon chiral perturbation theory, we carry out a parameter-free calculation of the threshold S factors for the solar $\mathrm{pp}$ (proton-fusion) and hep processes in an effective field theory (EFT) that combines the merits of the standard nuclear physics method and systematic chiral expansion. The power of the EFT adopted here is that one can correlate in a unified formalism the weak-current matrix elements of two-, three-, and four-nucleon systems. Using the tritium $\ensuremath{\beta}$-decay rate as an input to fix the only unknown parameter in the theory, we can evaluate the threshold S factors with drastically improved precision; the results are ${S}_{\mathrm{pp}}(0)=3.94\ifmmode\times\else\texttimes\fi{}(1\ifmmode\pm\else\textpm\fi{}0.004)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}25}\mathrm{MeV}\mathrm{}\mathrm{b}$ and ${S}_{\mathrm{hep}}(0)=(8.6\ifmmode\pm\else\textpm\fi{}1.3)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}20}\mathrm{keV}\mathrm{}\mathrm{b}.$ The dependence of the calculated S factors on the momentum cutoff parameter $\ensuremath{\Lambda}$ has been examined for a physically reasonable range of $\ensuremath{\Lambda}.$ This dependence is found to be extremely small for the $\mathrm{pp}$ process, and to be within acceptable levels for the hep process, substantiating the consistency of our calculational scheme.

Liang-In Lin, Yuh-Fen Ke, Y. Ko et al.

S. Dramsi, P. Cossart

Po-Lin Kuo, Cc Lin

S. Aherne, N. O'Brien

F. Xie, Chunfu Wu, W. Lai et al.

Herba epimedii (HEP) is one of the most frequently used herbs prescribed for treatment of osteoporosis in China. In the present study, the in vivo effects of HEP extract on bone metabolism were evaluated using 4-month-old ovariectomized (OVX) or sham-operated (Sham) female Sprague-Dawley rats orally administered with HEP extract (110 mg kg−1d−1), 17ß-estrogen (2 mg kg−1d−1) or its vehicle for 3 months. HEP extract significantly decreased urinary calcium excretion, suppressed serum alkaline phosphatase (ALP) activity and urinary deoxypyridinoline levels in OVX rats (P < 0.05 versus vehicle-treated OVX rats). Histomorphometric analysis indicated that HEP extract could prevent OVX-induced bone loss by increasing tibial trabecular bone area and decreasing trabecular separation in OVX rats (P < 0.05 versus vehicle-treated OVX group). The in vitro effects of HEP extract were also studied using rat osteoblast-like UMR 106 cells. HEP extract significantly stimulated cell proliferation in a dose-dependent manner (P < 0.01 versus vehicle-treated) and increased ALP activity at 200 μgml−1 (P < 0.01 versus vehicle-treated) in UMR 106 cells. It modulated osteoclastogenesis by increasing osteoprotegrin (OPG) mRNA and decreasing receptor activator of NF-κB ligand (RANKL) mRNA expression, resulting in a dose-dependent increase in OPG/RANKL mRNA ratio (P < 0.01 versus vehicle-treated). Taken together, HEP treatment can effectively suppress the OVX-induced increase in bone turnover possibly by both an increase in osteoblastic activities and a decrease in osteoclastogenesis. The present study provides the evidence that HEP can be considered as a complementary and alternative medicine for treatment of post-menopausal osteoporosis.

Y. Hsu, Po-Lin Kuo, Chun‐ching Lin