Intramural delivery of bortezomib inhibits restenosis following arterial injury

BACKGROUND

Several studies have demonstrated that the proteasome inhibitors prevent restenosis following arterial injury. The proteasome inhibitor bortezomib shows anti-inflammatory and antiproliferative effects. Here, we evaluate the efficacy of bortezomib in inhibiting the restenosis following arterial injury and the effect on nuclear factor kappa B (NF-kappaB) and p27.

METHODS

An injured iliac artery rabbit model was established by balloon over-stretching. Rabbits were intramurally infused with bortezomib or normal saline by a transport coronary dilatation catheter in the bortezomib (n = 20) or control (n = 20) groups, respectively, and they were sacrificed on the 7th or 21th day following the arterial injury. Neointimal area was measured by computer analysis of photomicrographs, while expression of NF-kappaB and of p27 on day 7 were evaluated by Western blotting and immunohistochemistry, respectively.

RESULTS

Expression of p27 (56.10 ± 3.03% vs. 10.24 ± 0.60%, p < 0.05) was significantly higher while that of NF-kappaB (0.44 ± 0.02 vs. 0.70 ± 0.03, p < 0.05) was significantly lower in the bortezomib group than in control group on day 7 after arterial injury. Neointimal formation was significantly lower in the bortezomib group on day 21 after arterial injury (0.67 ± 0.03 vs. 1.30 ± 0.05 intima/media ratio, p < 0.05).

CONCLUSIONS

Intramural delivery of bortezomib reduces neointimal formation, possibly via a mechanism involving upregulation of the p27 and downregulation of the NF-kappaB. Bortezomib therefore may be an alternative therapeutic approach for preventing restenosis.

Visualization of the internal cerebral veins on MR phase-sensitive imaging: comparison with 3D gadolinium-enhanced MR venography and fast-spoiled gradient recalled imaging

The purpose of this article is to compare the visualization quality of ICV and their tributaries on PSI-MRV, 3D CE-MRV, and 3D CE-FSPGR. PSI-MRV has been shown to delineate the ICV, TSV, SV, anterior caudate nucleus veins, and medial atrial veins effectively. Due to its advantages of no contrast material injection, acceptable examination times, and no arterial contamination, PSI-MRV should be considered in the evaluation of deep cerebral veins.

Implications of QRS duration in dogs with pacing-induced heart failure

The objective of this study was to find out the implication of QRS duration in dogs with rapid pacing-induced heart failure. Sixteen Beagle dogs were implanted with transvenous cardiac pacemakers and underwent rapid right ventricular pacing for 3 weeks at 260 bpm to induce heart failure. Dogs were divided into two groups according to the QRS duration: 9 with normal QRS duration (<100 ms) and 7 with prolonged QRS duration (≥100 ms). Cardiac systolic function and size was analyzed by real time 3-dimensional echocardiography and left ventricular dyssynchrony was assessed by speckle tracking strain imaging. Congestive heart failure developed 3 weeks after rapid right ventricular pacing. Dogs with prolonged QRS duration showed more extensive radial strain and circumferential strain dyssynchrony than dogs with normal QRS duration. At the end of 4-week recovery, greater improvement of left ventricular ejection fraction and left ventricular end-systolic volume was detected in dogs with normal QRS duration. The findings suggested that left ventricular dyssynchrony, indicated by a prolonged QRS duration, predicted an unsatisfying recovery in dogs with rapid pacing-induced heart failure. QRS duration had the potential to be a prognostic indicator for dogs with heart failure.

Isolation and characterization of five rice telomere-associated sequences

Acoording to the telomere-repeated sequences of rice, two primers: (TTTAGGG11)(3) and (CCC-TAA.A)(3)CCC were used to amplify rice telomere-assciated sequences (TASs). Fox PCR template preparation. total DNA was digested with restrictive endonuclease and then ligated. Using the ligates or total DNA sa template, eight fragments were obtained with the single primer by the PCR reaction. To confirm that the sequences are derived from telomeric DNA, we conducted Bal31 digestion analysis. Of the eight fragments, seven were susceptible to Bal31 treatment, suggesting that they were TASs. These DNA fragments were further demonstrated u, be rice sub-telomeric sequences by RFLP mapping Five sequences have been mapped to the distal ends on rice chromme 5,6,7 and 9, and two other sequences have been mapped at interstitial sites, suggesting that (TTTAGGG)(n). also exist in the middle of rice chromosomes-All eight fragments were sequenced and characterized.

Polystyrene nanoparticles activate ion transport in human airway epithelial cells

BACKGROUND

Over the last decade, nanotechnology has provided researchers with new nanometer materials, such as nanoparticles, which have the potential to provide new therapies for many lung diseases. In this study, we investigated the acute effects of polystyrene nanoparticles on epithelial ion channel function.

METHODS

Human submucosal Calu-3 cells that express cystic fibrosis transmembrane conductance regulator (CFTR) and baby hamster kidney cells engineered to express the wild-type CFTR gene were used to investigate the actions of negatively charged 20 nm polystyrene nanoparticles on short-circuit current in Calu-3 cells by Ussing chamber and single CFTR Clchannels alone and in the presence of known CFTR channel activators by using baby hamster kidney cell patches.

RESULTS

Polystyrene nanoparticles caused sustained, repeatable, and concentration-dependent increases in short-circuit current. In turn, these short-circuit current responses were found to be biphasic in nature, ie, an initial peak followed by a plateau. EC(50) values for peak and plateau short-circuit current responses were 1457 and 315.5 ng/mL, respectively. Short-circuit current was inhibited by diphenylamine-2-carboxylate, a CFTR Cl(-) channel blocker. Polystyrene nanoparticles activated basolateral K(+) channels and affected Cl(-) and HCO(3) (-) secretion. The mechanism of short-circuit current activation by polystyrene nanoparticles was found to be largely dependent on calcium-dependent and cyclic nucleotide-dependent phosphorylation of CFTR Cl(-) channels. Recordings from isolated inside-out patches using baby hamster kidney cells confirmed the direct activation of CFTR Cl(-) channels by the nanoparticles.

CONCLUSION

This is the first study to identify the activation of ion channels in airway cells after exposure to polystyrene-based nanomaterials. Thus, polystyrene nanoparticles cannot be considered as a simple neutral vehicle for drug delivery for the treatment of lung diseases, due to the fact that they may have the ability to affect epithelial cell function and physiological processes on their own.

Cross section and parity-violating spin asymmetries of W± boson production in polarized p + p collisions at sqrt[s] = 500 GeV

Large parity-violating longitudinal single-spin asymmetries A(L)(e+) = -0.86(-0.14) (+0.30) and A(L)(e-) = 0.88(-0.71) (+0.12) are observed for inclusive high transverse momentum electrons and positrons in polarized p+p collisions at a center-of-mass energy of sqrt[s] = 500 GeV with the PHENIX detector at RHIC. These e± come mainly from the decay of W± and Z0 bosons, and their asymmetries directly demonstrate parity violation in the couplings of the W± to the light quarks. The observed electron and positron yields were used to estimate W± boson production cross sections for the e± channels of σ(pp → W+ X) × BR(W+ → e+ ν(e)) = 144.1 ± 21.2(stat)(-10.3) (+3.4) (syst) ± 21.6(norm)  pb, and σ(pp → W- X) × BR(W- → e- ν[over ¯](e)) = 31.7 ± 12.1(stat)(-8.2) (+10.1) (syst) ± 4.8(norm)  pb.

Energy loss for heavy quarks in relation to light partons: is radiative energy loss for heavy quarks anomalous?

The scaling properties of jet-suppression measurements are compared for nonphotonic electrons (e+/-) and neutral pions (pi(0)) in Au+Au collisions at sqrt[S(NN)]=200 GeV. For a broad range of transverse momenta and collision centralities, the comparison is consistent with jet quenching dominated by radiative energy loss for both heavy and light partons. Less quenching is indicated for heavy quarks via e+/-; this gives an independent estimate of the transport coefficient q that agrees with its magnitude obtained from quenching of light partons via pi(0)'s.

Dietary nucleotides protect thymocyte DNA from damage induced by cyclophosphamide in mice

The effects of dietary nucleotides on thymocyte DNA damages induced by cyclophosphamide (CP) in mice were examined. First, phase I experiment was conducted to determine the optimal timing of detecting thymocyte DNA damages induced by CP (150 mg/kg body weight) in mice. Thymocyte DNA damages was determined at 6, 12, 18, 24 h by single-cell gel electrophosphoresis assay (comet assay) after intraperitoneal injection of CP. The levels of DNA damage at 6, 12, 18, 24 h were all significantly higher than that of the control group (p < 0.01). The highest level of DNA damage appeared at 18 h and then decreased at 24 h. Therefore, 18 h was selected to determine DNA damages induced by CP in subsequent experiments. In phase II experiment, 30 male KunMing mice were divided into three treatments: negative control (NC), positive control (PC) and nucleotides group (NG). Mice in NC and PC were fed nucleotide-free diet, and mice in NG were fed nucleotide-supplemented diet (supplemented with 0.25% nucleotides, a mixture containing equal amounts of AMP, CMP, GMP and UMP). Mice in PC and NG groups were injected with CP (150 mg/kg body weight) at 21 days. DNA damage in thymocytes was evaluated at 18 h after CP treatment. The results indicate that dietary nucleotides do not affect the weights of the thymus and the spleen, or their organ indices (p > 0.05), but significantly decrease the percentage of comet cells and comet tail sizes (p < 0.01). This study demonstrates that dietary nucleotides could reduce the level of thymocyte DNA damage induced by CP in mice.

Enhancement of Mucosal Immune Responses in Chickens by Oral Administration of Cysteamine

Somatostatin, a tetradecapeptide originally isolated from the hypothalamus, can exert an inhibitory effect on the secretion of growth hormone by the anterior pituitary gland. In addition to endocrine organs, somatostatin is also present in the digestive tract and immune organs. In lymphoid tissues, somatostatin appears to play a role in the modulation of the immune response. Cysteamine (CS) is a sulfhydryl reducing agent that is known as a depletory agent of somatostatin. To evaluate its effects on chicken mucosal immune responses, CS was administrated orally to 1-wk-old broilers (40 mg/kg) that were immunized orally with Newcastle disease attenuated vaccine (NDV). The number of IgA-positive cells and intestinal intraepithelial lymphocytes (iIEL) in duodenum and jejunum were examined at 3-, 5-, and 7-wk posttreatment and immunization. The number of somatostatin-positive cells and relative amounts of somatostatin mRNA were also examined in the duodenum. The number of somatostatin-positive cells in the duodenum was reduced (P < 0.05) after CS treatment. In broilers receiving CS and NDV treatment (CS+NDV) the level of IgA-positive cells and iIEL in the duodenum and jejunum was increased (P < 0.05) at 3 and 5 wk posttreatment. The expression of somatostatin mRNA increased (P < 0.05) compared with that of the control group at 5 wk after immunization in broilers receiving CS+NDV or NDV alone. The results suggest that CS can induce proliferation and differentiation of IgA-positive cells and iIEL in the intestinal mucosa of chickens by reducing the number of somatostatin-positive cells.