Dimensional structural constants from chiral and conformal bosonization of QCD

We derive the dimensional non-perturbative part of the QCD effective action for scalar and pseudoscalar meson fields by means of chiral and conformal bosonization. The related structural coupling constants L_5 and L_8 of the chiral lagrangian are estimated using general relations which are valid in a variety of chiral bosonization models without explicit reference to model parameters. The asymptotics for large scalar fields in QCD is elaborated, and model-independent constraints on dimensional coupling constants of the effective meson lagrangian are evaluated. We determine also the interaction between scalar quarkonium and the gluon density and obtain the scalar glueball-quarkonium potential.Comment: 21 pages, LaTe

Lorentz and CPT Violating Chern-Simons Term in the Derivative Expansion of QED

We calculate by the method of dimensional regularization and derivative expansion the one-loop effective action for a Dirac fermion with a Lorentz-violating and CPT-odd kinetic term in the background of a gauge field. We show that this term induces a Chern-Simons modification to Maxwell theory. Some related issues are also discussed.Comment: 6 pages, no figure, RevTex, A revised versio

Lorentz and CPT symmetries in commutative and noncommutative spacetime

We investigate the fermionic sector of a given theory, in which massive and charged Dirac fermions interact with an Abelian gauge field, including a non standard contribution that violates both Lorentz and CPT symmetries. We offer an explicit calculation in which the radiative corrections due to the fermions seem to generate a Chern-Simons-like effective action. Our results are obtained under the general guidance of dimensional regularization, and they show that there is no room for Lorentz and CPT violation in both commutative and noncommutative spacetime.Comment: RevTex4, 7 pages, to be published in J. Phys.

Inhomogeneous Field Configurations and the Electroweak Phase Transition

We investigate the effects of inhomogeneous scalar field configurations on the electroweak phase transition. For this purpose we calculate the leading perturbative correction to the wave function correction term Z(\vph,T), i.e., the kinetic term in the effective action, for the electroweak Standard Model at finite temperature and the top quark self--mass. Our finding for the fermionic contribution to Z(\vph,T) is infra--red finite and disagrees with other recent results. In general, neither the order of the phase transition nor the temperature at which it occurs change, once Z(\vph,T) is included. But a non--vanishing, positive (negative) Z(\vph,T) enhances (decreases) the critical droplet surface tension and the strength of the phase transition. We find that in the range of parameter space, which allows for a first--order phase transition, the wave function correction term is negative --- indicating a weaker phase transition --- and especially for small field values so large that perturbation theory becomes unreliable.Comment: 23 pages of LaTeX + 3 PostScript figures included in uuencoded form, FERMI-PUB-93/253-

Stromal Vascular Fraction Transplantation as an Alternative Therapy for Ischemic Heart Failure: Anti-inflammatory Role

<p>Abstract</p> <p>Background</p> <p>The aims of this study were: (1) to show the feasibility of using adipose-derived stromal vascular fraction (SVF) as an alternative to bone marrow mono nuclear cell (BM-MNC) for cell transplantation into chronic ischemic myocardium; and (2) to explore underlying mechanisms with focus on anti-inflammation role of engrafted SVF and BM-MNC post chronic myocardial infarction (MI) against left ventricular (LV) remodelling and cardiac dysfunction.</p> <p>Methods</p> <p>Four weeks after left anterior descending coronary artery ligation, 32 Male Lewis rats with moderate MI were divided into 3 groups. SVF group (n = 12) had SVF cell transplantation (6 × 10⁶cells). BM-MNC group (n = 12) received BM-MNCs (6 × 10⁶) and the control (n = 10) had culture medium. At 4 weeks, after the final echocardiography, histological sections were stained with Styrus red and immunohistochemical staining was performed for α-smooth muscle actin, von Willebrand factor, CD3, CD8 and CD20.</p> <p>Results</p> <p>At 4 weeks, in SVF and BM-MNC groups, LV diastolic dimension and LV systolic dimension were smaller and fractional shortening was increased in echocardiography, compared to control group. Histology revealed highest vascular density, CD3+ and CD20+ cells in SVF transplanted group. SVF transplantation decreased myocardial mRNA expression of inflammatory cytokines TNF-α, IL-6, MMP-1, TIMP-1 and inhibited collagen deposition.</p> <p>Conclusions</p> <p>Transplantation of adipose derived SVF cells might be a useful therapeutic option for angiogenesis in chronic ischemic heart disease. Anti-inflammation role for SVF and BM transplantation might partly benefit for the cardioprotective effect for chronic ischemic myocardium.</p

Effect of tissue-harvesting site on yield of stem cells derived from adipose tissue: implications for cell-based therapies

The stromal vascular fraction (SVF) of adipose tissue contains an abundant population of multipotent adipose-tissue-derived stem cells (ASCs) that possess the capacity to differentiate into cells of the mesodermal lineage in vitro. For cell-based therapies, an advantageous approach would be to harvest these SVF cells and give them back to the patient within a single surgical procedure, thereby avoiding lengthy and costly in vitro culturing steps. However, this requires SVF-isolates to contain sufficient ASCs capable of differentiating into the desired cell lineage. We have investigated whether the yield and function of ASCs are affected by the anatomical sites most frequently used for harvesting adipose tissue: the abdomen and hip/thigh region. The frequency of ASCs in the SVF of adipose tissue from the abdomen and hip/thigh region was determined in limiting dilution and colony-forming unit (CFU) assays. The capacity of these ASCs to differentiate into the chondrogenic and osteogenic pathways was investigated by quantitative real-time polymerase chain reaction and (immuno)histochemistry. A significant difference (P = 0.0009) was seen in ASC frequency but not in the absolute number of nucleated cells between adipose tissue harvested from the abdomen (5.1 ± 1.1%, mean ± SEM) and hip/thigh region (1.2 ± 0.7%). However, within the CFUs derived from both tissues, the frequency of CFUs having osteogenic differentiation potential was the same. When cultured, homogeneous cell populations were obtained with similar growth kinetics and phenotype. No differences were detected in differentiation capacity between ASCs from both tissue-harvesting sites. We conclude that the yield of ASCs, but not the total amount of nucleated cells per volume or the ASC proliferation and differentiation capacities, are dependent on the tissue-harvesting site. The abdomen seems to be preferable to the hip/thigh region for harvesting adipose tissue, in particular when considering SVF cells for stem-cell-based therapies in one-step surgical procedures for skeletal tissue engineering

Rat Adipose Tissue-Derived Stem Cells Transplantation Attenuates Cardiac Dysfunction Post Infarction and Biopolymers Enhance Cell Retention

Background: Cardiac cell transplantation is compromised by low cell retention and poor graft viability. Here, the effects of co-injecting adipose tissue-derived stem cells (ASCs) with biopolymers on cell cardiac retention, ventricular morphometry and performance were evaluated in a rat model of myocardial infarction (MI). Methodology/Principal Findings: (99m)Tc-labeled ASCs (1 x 10(6) cells) isolated from isogenic Lewis rats were injected 24 hours post-MI using fibrin a, collagen (ASC/C), or culture medium (ASC/M) as vehicle, and cell body distribution was assessed 24 hours later by gamma-emission counting of harvested organs. ASC/F and ASC/C groups retained significantly more cells in the myocardium than ASC/M (13.8+/-2.0 and 26.8+/-2.4% vs. 4.8+/-0.7%, respectively). Then, morphometric and direct cardiac functional parameters were evaluated 4 weeks post-MI cell injection. Left ventricle (LV) perimeter and percentage of interstitial collagen in the spare myocardium were significantly attenuated in all ASC-treated groups compared to the non-treated (NT) and control groups (culture medium, fibrin, or collagen alone). Direct hemodynamic assessment under pharmacological stress showed that stroke volume (SV) and left ventricle end-diastolic pressure were preserved in ASC-treated groups regardless of the vehicle used to deliver ASCs. Stroke work (SW), a global index of cardiac function, improved in ASC/M while it normalized when biopolymers were co-injected with ASCs. A positive correlation was observed between cardiac ASCs retention and preservation of SV and improvement in SW post-MI under hemodynamic stress. Conclusions: We provided direct evidence that intramyocardial injection of ASCs mitigates the negative cardiac remodeling and preserves ventricular function post-MI in rats and these beneficial effects can be further enhanced by administrating co-injection of ASCs with biopolymers.Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)[01/0009-0]Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)[05/54695-3]Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)[04/06784-4]Ministerio da Ciencia e Tecnologia/Conselho Nacional de Desenvolvimento Cientifico e Tecnologico/Ministerio da Saude/Departamento Ciencia e Tecnologia (MCT/CNPq/MS/DECIT)[552324/20005-1]Ministerio da Ciencia e Tecnologia/Conselho Nacional de Desenvolvimento Cientifico e Tecnologico/Ministerio da Saude/Departamento Ciencia e Tecnologia (MCT/CNPq/MS/DECIT)[10120104096700]CNPq[141276/2004-5