8,523 research outputs found
A possible involvement of ion transporter in tumor necrosis factor alpha and cycloheximide-induced apoptosis of endothelial cells.
We examined the tumor necrosis factor alpha (TNFalpha)-induced apoptosis of vascular endothelial cells from the standpoint of ion channels. Cultured vascular endothelial cells from bovine carotid artery were used. Apoptosis was determined by a propidium iodide assay. Treatment of the endothelial cells with TNFalpha and cycloheximide for 6 h induced nuclear fragmentation in a TNFalpha dose-dependent manner (1-10 ng/ml). Concomitant treatment of endothelial cells with TNFalpha at a dose of 10 ng/ml and cycloheximide at a dose of 10 microg/ml elicited endothelial cell apoptosis as high as 23.4+/-4.1% at 6 h after administration. However, 10 ng/ml TNFalpha alone elicited a little apoptosis at 6 h after its administration (% apoptosis=4.1+/-0.8%). Cycloheximide (10 microg/ml) did not induce apoptosis at all. Concomitant treatment of endothelial cells with 1 mmol/l of 4,4-diisothiocyanatostilbene-2,2-disulfonic acid, which is a chloride bicarbonate exchanger blocker, partially inhibited the TNFalpha and cycloheximide-induced endothelial cell apoptosis. On the other hand, endothelial cell apoptosis due to TNFalpha and cycloheximide was completely inhibited by benzyloxycarbonyl-Asp-CH2OC(O)-2,6-dichlorobenzene (50 micromol/l), an inhibitor of caspase. Moreover, pyrrolidine dithiocarbanate, an inhibitor of nuclear factor kappa B (NF-kappaB), also suppressed endothelial cell apoptosis induced by TNFalpha and cycloheximide completely. These findings suggest that the endothelial cell apoptosis induced by TNFalpha and cycloheximide is closely related to not only chloride ions, but also both NF-kappaB and caspase activation. That is to say, there is a possibility that chloride ions or bicarbonate (pH) may play an important role in signal transduction such as NF-kappaB and caspase activation in the apoptosis induced by TNFalpha and cycloheximide
Can adenine nucleotides predict primary nonfunction of the human liver homograft?
Sixty-eight primary liver grafts were analyzed to see whether adenine nucleotides (AN: ATP, ADP, and AMP) or purine catabolites (PC: adenosine, inosine, hypoxanthine, and xanthine) of tissue or effluent can predict primary graft nonfunction. AN, PC, and nicotinamide adenine dinucleotide, oxidized form (NAD+) of the tissue before (pretransplant) and after graft reperfusion (post-transplant) and of the effluent were analyzed. The graft outcome was classified into two groups (group A: successful, n = 64; group B: primary nonfunctioning, n = 4). No significant differences were observed in pretransplant measurements between groups A and B, whereas ATP, ADP, total AN, total AN + total PC (T) and NAD+, in post-transplant tissues, were significantly higher in group A. Xanthine in the effluent was significantly higher in group B than in group A. ATP, ADP, total AN, T, and NAD+ in post-transplant tissue were significantly associated with primary graft nonfunction by logistic regression analysis
Hyperfine Anomaly of Be Isotopes and Anomalous Large Anomaly in Be
A new result of investigations of the hyperfine structure (hfs) anomaly in Be
isotopes is presented. The hfs constant for Be is obtained by using the
core plus neutron type wave function: . A large hfs anomaly of Be is found, which is mainly due
to a large radius of the halo single particle state.Comment: 14 pages, Late
g-factor of a tightly bound electron
We study the hyperfine splitting of an electron in hydrogen-like . It is found that the hfs energy splitting can be explained well by
considering the g-factor reduction due to the binding effect of a bound
electron. We determine for the first time the experimental value of the
magnetic moment of a tightly bound electron.Comment: 6 pages, Latex, Phys. Rev. A in pres
Finite size corrections in massive Thirring model
We calculate for the first time the finite size corrections in the massive
Thirring model. This is done by numerically solving the equations of periodic
boundary conditions of the Bethe ansatz solution. It is found that the
corresponding central charge extracted from the term is around 0.4 for
the coupling constant of and decreases down to zero when
. This is quite different from the predicted central
charge of the sine-Gordon model.Comment: 8 pages, Latex, 2 figure
Evidence for forward scattering and coupling to acoustic phonon modes in high-T cuprate superconductors
Recent laser angle-resolved photoemission spectroscopy studies have
established the presence of a new kink in the low-energy nodal dispersion of
BiSrCaCuO (Bi-2212). The energy scale (~8-15 meV) of
this kink appears below the maximum of the superconducting gap .
Therefore it is difficult to interpret this feature in terms of the usual
coupling to a sharp dispersionless mode. In this paper we examine
electron-phonon coupling to the in-plane acoustic phonon branch arising from
the modulation of the screened Coulomb potential. We demonstrate that such a
coupling has a strong forward scattering peak, and as a consequence, a kink
occurs in the dispersion at an energy scale shifted by the local gap
. In addition, considerations for the reduction of screening with
underdoping naturally explains the observed doping dependence of the low-energy
kink. These results point to a strong coupling to the acoustic branch which is
peaked in the forward scattering direction and has important implications for
transport and pairing in the high-T cuprates.Comment: 4.5 pages, 4 figures, Submitted to PR
Expression of hyaluronan synthase 3 in deformed human temporomandibular joint discs: in vivo and in vitro studies
The present study aimed at investigating the expression of a hyaluronan synthase (HAS) 3 in tissue samples of deformed human temporomandibular joint (TMJ) discs and cells obtained from the discs. Fifteen adult human TMJ discs (twelve diseased discs and three normal discs) were used in this study. The twelve diseased discs were obtained from twelve patients with internal derangement (ID) of TMJ. These patients all had anteriorly displaced discs and deformed discs. The tissues were immunohistochemically stained using HAS3 antibodies. In addition, the subcultured TMJ disc cells under both normal and hypoxic conditions (O2: 2%) were incubated for 3, 6, 12, and 24 h after addition of interleukin-1β (IL-1β) (1 ng/mL). Subsequently, the expression of HAS3 was examined using real-time reverse transcription-polymerase chain reaction (RT-PCR). The control group showed from negative to weak positive reactions for HAS3 on immunohistochemical staining. The discs extracted from twelve cases with ID presented from moderate to strong positive reactions for HAS3. The quantity of HAS3 mRNA was compared with a control group, and showed a 204-fold increase at 3 h, a 26-fold increase at 6 h, a 2.5-fold increase at 12 h and a 32-fold increase at 24 h under hypoxia with the addition of IL-1β. The expression of HAS3 mRNA was significantly enhanced at 3 h and 24 h. The results obtained suggest that HAS3 is related to the pathological changes of human TMJ discs affected by ID
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