Heme oxygenase-1 protects INF-gamma primed endothelial cells from Jurkat T-cell adhesion

PURPOSE

The heme oxygenase-1 (HO-1) system is associated with the rate-limiting step of conversion of heme, one of the most critical roles in cytoprotective mechanisms. Our study investigated its potential role in protection of endothelial cells from T cells.

METHODS

The recombinant plasmid pcDNA3-HO-1 was transfected into endothelial cells. Indirect fluorescent staining was used to examine the expression of HO-1 protein. Then endothelial cells primed by INF-gamma were mixed in culture with Jurkat T cells labeled with carboxyfluorescein diacetate succinimidyl ester (CFSE). The number of adhesive Jurkat T cells was determined using FACS to evaluate the adhesion effect. After being cultured with endothelial cells, the cell cycle of Jurkat T cells was detected using FACS.

RESULTS

Expression of HO-1 on endothelial cells conferred significant protection against Jurkat T-cell-mediated adhesion. The rate of Jurkat T-cell adhesions was reduced to 19.06%, in contrast with 31.42% in the control group (P<.05). After using ZnPP, an inhibitor of HO-1, the rate of Jurkat T-cell adhesion recovered to 29.08%. The binding activities between endothelial cells and Jurkat T cells was blocked by HO-1 expression. The proliferation of Jurkat T cells was inhibited after culture with endothelial cells, which had been transfected with HO-1, which blocked cell cycle entry of T cells. More than 60% of Jurkat T cells remained in G0/G1 compared with 40% among the control group.

CONCLUSION

HO-1 directly protected endothelial cells primed by INF-gamma from Jurkat T cells and down-regulated the expression of HLA-DR on the surface of endothelial cells. These results indicated that transgenic expression of HO-1 may be useful to prevent lymphocytes from responding to endothelial cells.

Zener double exchange from local valence fluctuations in magnetite

Magnetite (Fe3O4) is a mixed valent system where electronic conductivity occurs on the B site (octahedral) iron sublattice of the spinel structure. Below T(V)=123 K, a metal-insulator transition occurs which is argued to arise from the charge ordering of 2+ and 3+ iron valences on the B sites (Verwey transition). Inelastic neutron scattering measurements show that optical spin waves propagating on the B site sublattice (approximately 80 meV) are shifted upwards in energy above T_{V} due to the occurrence of B-B ferromagnetic double exchange in the mixed valent phase. The double exchange interaction affects only spin waves of Delta(5) symmetry, not all modes, indicating that valence fluctuations are slow and the double exchange is constrained by short-range electron correlations above T(V).

Orbital fluctuations and orbital flipping in RVO3 perovskites

The effect of the average R-site ionic radius IR and variance on the orbital and magnetic order in R3+-doped YVO3 was studied in Y1-xLaxVO3 and Y1-x(La0.2337Lu0.7663)xVO3 with fixed IR. The orbital flipping temperature T{CG} increases nonlinearly with increasing R-site variance, indicating that the V-O-V bond angle is not the primary driving force stabilizing the C-type orbitally ordered phase. The suppressed thermal conductivity in the G-type orbitally ordered phase signals some remaining orbital randomness that is enhanced by t{2} and et hybridization in {3}T{1g} site symmetry.

Damping of antiferromagnetic spin waves by valence fluctuations in the double layer perovskite YBaFe2O5

Inelastic neutron scattering experiments show that spin dynamics in the charge-ordered insulating ground state of the double layer perovskite YBaFe(2)O(5) is well described in terms of e(g) superexchange interactions. Above the Verwey transition at T(V)=308 K, t(2g) double exchange-type conduction proceeds within antiferromagnetic FeO(2)-BaO-FeO(2) double layers by an electron hopping process that requires a spin flip of the five-coordinated Fe ions, costing an energy of 5<J>S(2) approximately 0.1 eV. The hopping process disrupts near-neighbor spin correlations, leading to massive damping of zone-boundary spin waves.

Phase I/II study of enzastaurin plus temozolomide during and following radiation therapy in patients with newly diagnosed glioblastoma multiforme (GBM) or gliosarcoma

12511

Background: Enzastaurin is a potent, selective, oral serine/threonine kinase inhibitor of PKCβ, an enzyme activated by vascular endothelial growth factor (VEGF). VEGF is upregulated in most cases of GBM, producing significant angiogenesis. This study combines the anti-angiogenic properties of enzastaurin with the current standard treatment of radiation therapy (RT) and cytotoxic chemotherapy (temozolomide; TMZ). Methods: A Phase 1/2 study of enzastaurin with TMZ during and following RT is ongoing in patients with newly diagnosed GBM. Two doses of enzastaurin will be evaluated during Phase 1. The first 6 patients will received 250 mg of enzastaurin daily. If no more than one patient experiences a dose-limiting toxicity (DLT) during RT and the first adjuvant cycle, an additional 6 patients will receive an escalated dose of 500 mg daily. The dose established in Phase 1 will be administered to 60 patients in Phase 2. The primary objective of Phase 2 is to determine the efficacy of enzastaurin as measured by overall survival. Multiple pharmacokinetic (PK) and pharmacodynamic (PD) endpoints will be evaluated using perfusion imaging and plasma biomarkers. Relevant growth factors and pathways will be analyzed in primary tumor tissue from each patient. Results: Since September 06, 6 patients have completed RT with concurrent enzastaurin (250 mg) and TMZ. None of these patients has experienced a DLT to date. It is expected that an additional 6 patients will be enrolled in January 07 and Phase 2 will start in May 2007. Conclusions: Enzastaurin with concurrent RT and TMZ appears safe. Final Phase 1 safety results and preliminary PK and PD data will be presented.

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Joint NABTC + NCCTG prognostic factors analysis for high grade recurrent glioma

2075

Background: Multiple variables may impact endpoints used to assess therapeutic efficacy for patients with recurrent gliomas. To identify prognostic factors for each of 3 outcome variables, a master analysis file was constructed by pooling datasets summarizing key baseline factors and outcomes obtained in 15 North Central Cancer Treatment Group (NCCTG) trials (n=583, 1980–2004) and 12 North American Brain Tumor Consortium (NABTC) trials (n=596, 1998–2002). Methods: In addition to traditional variables (gender, age, performance score (PS), race, extent of primary resection, year of study entry, last known histology, time since initial diagnosis, baseline steroid use, prior chemotherapy (Y/N), prior nitrosoureas, baseline anticonvulsant use), we investigated prior t (TMZ), number of relapses, academic vs. community site and low grade at initial diagnosis. Outcome variables were: (1) overall survival (OS), (2) progression free survival (PFS) and (3) PFS6 = proportion of patients alive and progression-free 6 months after start of treatment. For all 3 endpoints, Classification and Regression Tree (CART) models and bootstrap samples were used to identify prognostic variables and to look for evidence of interactions among the independent variables affecting outcome. Results: For all outcomes the initial CART analysis selected last known grade (4 vs. 3) as the most important variable. Additional factors selected as predicting poor prognosis differed with grade and outcome measure and included prior TMZ, longer time since primary diagnosis, older age and poor PS. Community vs. academic was not a strong predictor in any of the models nor was low grade at initial diagnosis. Additional analyses are planned to better describe the impact of all the variables on outcome, including use of Cox models and logistic models considering all baseline variables with backwards selection. Conclusions: The results from analyses to date are consistent with current thinking that last known histology (grade) is an important factor. Time since initial diagnosis is likely a surrogate for number of relapses. More definitive conclusions await the completion of ongoing analyses.

No significant financial relationships to disclose.

Stabilization of charge ordering in La1/3Sr2/3FeO3-delta by magnetic exchange

The magnetic exchange energies in charge ordered La1/3Sr2/3FeO3-delta (LSFO) and its parent compound LaFeO3 (LFO) have been determined by inelastic neutron scattering. In LSFO, the measured ratio of ferromagnetic exchange between Fe3+-Fe5+ pairs (JF) and antiferromagnetic exchange between Fe3+-Fe3+ pairs (JAF) fulfills the criterion for charge ordering driven by magnetic interactions (|JF/JAF|>1). The 30% reduction of JAF as compared to LFO indicates that doped holes are delocalized, and charge ordering occurs without a dominant influence from Coulomb interactions.

Laparoscopy as a routine approach for left lateral sectionectomy

BACKGROUND

Since 1997, the authors have performed laparoscopic left lateral sectionectomy of lesions of the liver in preference to open surgery. The aim of this study was to assess the outcome.

METHODS

Between October 1997 and March 2005, 36 laparoscopic left lateral sectionectomies were performed using five trocars and a small incision for specimen retrieval. Liver resection was performed mainly using a harmonic scalpel and staplers. The Pringle manoeuvre was used in 24 patients.

RESULTS

The mean patient age was 55.2 (range 31-80) years. Twelve patients had underlying cirrhosis. Surgery was performed for 20 malignant lesions and 16 benign lesions with a mean size of 42.7 (range 5-110) mm. Conversion to laparotomy occurred in one patient. The mean operating time was 171.5 (range 90-240) min. Operatiing time and use of the Pringle manoeuvre were significantly decreased in the second half of the series. Mean blood loss was 208 (range 50-600) ml. No transfusion was required. There were no deaths. Two patients had postoperative complications (one incisional hernia and one pneumonia). The median postoperative stay was 5.2 days.

CONCLUSION

The laparoscopic approach to left lateral sectionectomy was safe and feasible in this series and could be considered as a routine approach in selected patients.

Fourier domain--optical coherence tomography based on a quadrature Mach-Zehnder interferometer

A quadrature Mach-Zehnder interferometer based on a 3 x 3 fiber coupler is presented. This novel interferometric platform is used in a homodyne configuration within an optical coherence tomography system. A fast swept laser source is used as light source. The complex interferometric signal is reconstructed so the complex conjugate ambiguity is removed. The features of this novel setup are discussed.

Olfactory sensory neurons in the sea lamprey display polymorphisms

The sea lamprey (Petromyzon marinus) is an ancient jawless fish phyletically removed from modern (teleost) fishes. It is an excellent organism in the study of olfaction due to its accessible olfactory pathway, which is susceptible to manipulation, and its important location in the evolution of vertebrates. There are many similarities in the olfactory systems of all fishes, and they also share characteristics with the olfactory system of mammals. Teleost fishes lack the distinctive vomeronasal organ of mammals; rather all odours are processed initially by olfactory sensory neurons (OSNs) of three morphotypes within the olfactory epithelium. We sought to identify olfactory sensory neuron polymorphisms in the sea lamprey. Using retrograde tracing with dyes injected into the olfactory bulb, we identified three morphotypes which are highly similar to those found in teleosts. This study provides the first evidence of morphotypes in the sea lamprey peripheral olfactory organ, and indicates that olfactory sensory neuron polymorphism may be a trait highly conserved throughout vertebrate evolution.