A comparison between the concentration of mast cells in squamous cell carcinomas of the skin and oral cavity

FUNDAMENTS: The lethality of squamous cell carcinomas (SCC) of the skin is considered low. SCC in the mouth is usually associated with poor prognosis. Current evidence suggests that mast cells in the normal tissue contribute to the tumorigenesis of SCC, probably by promoting angiogenesis. OBJECTIVE: The aim of this study was to compare the concentration of mast cells in SCC of the mouth and skin and evaluate whether there is a correlation with the degree of differentiation of these tumors. MATERIAL AND METHODS: Thirty cases of SCC of the skin and 34 of the mouth were investigated. Toluidine blue staining was used to identify mast cells in blocks containing the central portion of the neoplasm. RESULTS: A concentration of between 0 and 10 mast cells was found in one single case of SCC of the skin and there were no cases of SCC of the mouth with concentrations of mast cells in the tumor >201. In the majority of cases of SCC of the mouth (47%; n=16), mast cell concentration was between 0 and 10, with a concentration >51 mast cells in 80% of cases of SCC of the skin. All the cases of SCC of the mouth with a concentration of mast cells between 100 and 200 and 80% of those with a concentration of 51-99 were located on the lip. The concentration of mast cells was unrelated to the degree of differentiation of the tumor. CONCLUSION: The concentration of mast cells is lower in SCC of the mouth except when the tumor is located on the lip. This may reflect a lower need for cell activation in the microenvironment to improve vascularization in oral cancer.

Macrosegregation of Impurities in Directionally Solidified Silicon

Directional solidification of molten metallurgical-grade Si was carried out in a vertical Bridgman furnace. The effects of changing the mold velocity from 5 to 110 mu m seconds(-1) on the macrosegregation of impurities during solidification were investigated. The macrostructures of the cylindrical Si ingots obtained in the experiments consist mostly of columnar grains parallel to the ingot axis. Because neither cells nor dendrites can be observed on ingot samples, the absence of precipitated particles and the fulfillment of the constitutional supercooling criterion suggest a planar solid-liquid interface for mold velocities a parts per thousand currency sign10 mu m seconds(-1). Concentration profiles of several impurities were measured along the ingots, showing that their bottom and middle are purer than the metallurgical Si from which they solidified. At the ingot top, however, impurities accumulated, indicating the typical normal macrosegregation. When the mold velocity decreases, the macrosegregation and ingot purity increase, changing abruptly for a velocity variation from 20 to 10 mu m seconds(-1). A mathematical model of solute transport during solidification shows that, for mold velocities a parts per thousand yen20 mu m seconds(-1), macrosegregation is caused mainly by diffusion in a stagnant liquid layer assumed at the solid-liquid interface, whereas for lower velocities, macrosegregation increases as a result of more intense convective solute transport.

A role for ferritin in the antioxidant system in coffee cell cultures

Iron (Fe) is an essential nutrient for plants, but it can generate oxidative stress at high concentrations. In this study, Coffea arabica L. cell suspension cultures were exposed to excess Fe (60 and 240 mu M) to investigate changes in the gene expression of ferritin and antioxidant enzymes. Iron content accumulated during cell growth, and Western blot analysis showed an increase of ferritin in cells treated with Fe. The expression of two ferritin genes retrieved from the Brazilian coffee EST database was studied. CaFER1, but not CaFER2, transcripts were induced by Fe exposure. Phylogenetic analysis revealed that CaFER1 is not similar to CaFER2 or to any ferritin that has been characterised in detail. The increase in ferritin gene expression was accompanied by an increase in the activity of antioxidant enzymes. Superoxide dismutase, guaiacol peroxidase, catalase, and glutathione reductase activities increased in cells grown in the presence of excess Fe, especially at 60 mu M, while the activity of glutathione S-transferase decreased. These data suggest that Fe induces oxidative stress in coffee cell suspension cultures and that ferritin participates in the antioxidant system to protect cells against oxidative damage. Thus, cellular Fe concentrations must be finely regulated to avoid cellular damage most likely caused by increased oxidative stress induced by Fe. However, transcriptional analyses indicate that ferritin genes are differentially controlled, as only CaFER1 expression was responsive to Fe treatment.

Apoptosis induction by 4-nerolidylcatechol in melanoma cell lines

Pothomorphe umbellata, a native Brazilian plant, is popularly known to be effective in the treatment of skin lesions. This benefit is attributed to 4-nerolidylcatechol (4-NC) a compound extracted from P. umbellata. Since melanomas show prominent resistance to apoptosis and exhibit extreme chemoresistance to multiple forms of therapy, novel compounds addressing induction of cell death are worth investigating. Here, we evaluated effects on cell cycle progression and possible cytotoxic activity of 4-NC in melanoma cell lines as well as human dermal fibroblasts. Inhibitory effects on cell invasion and MMP activity were also investigated. 4-NC showed cytotoxic activity for all melanoma cell lilies tested (IC(50) = 20-40 mu M, 24 h for tumoral cell lines: IC(50) = 50 mu M for fibroblast cell line) associated with its capacity to induce apoptosis. Furthermore, this is the first time that 4-NC is described as an inhibitor of cell invasiveness, due mainly to a G I cell cycle arrest and inhibition of MMP-2 activity in melanoma cell lines. (C) 2008 Elsevier Ltd. All rights reserved.

Hydrostability and Scaling Up Molecular Sieve Silica (MSS) Membranes for H2/CO Separation in Fuel Cell Systems

MSS membranes are a good candidate for CO cleanup in fuel cell fuel processing systems due to their ability to selectively permeate H2 over CO via molecular sieving. Successfully scaled up tubular membranes were stable under dry conditions to 400°C with H2 permeance as high as 2 x 10-6 mol.m-2.s^-1.Pa^-1 at 200 degrees C and H2/CO selectivity up to 6.4, indicating molecular sieving was the dominant mechanism. A novel carbonised template molecular sieve silica (CTMSS) technology gave the scaled up membranes resilience in hydrothermal conditions up to 400 degrees C in 34% steam and synthetic reformate, which is required for use in fuel cell CO cleanup systems.

Semliki Forest virus as an expression vector in insect cell lines

Studies were undertaken to determine if replication-deficient Semliki Forest virus expression vectors could be successfully used to express foreign gene constructs in insect cell lines. Using green fluorescent protein (GFP) as a marker we recorded infection levels of nearly 100% in the Aedes albopictus cell lines C6/36 and Aa23T, as well as in the Ae. aegypti cell line MOS20. The virus was capable of infecting an Anopheles gambiae cell line MOS55. The amount of GFP protein produced in each cell line was quantified. Northern analysis of viral transcription revealed the presence of novel transcripts in Aa23T, C6/36, and MOS55 cell lines, but not in the BHK or MOS20. The initial characterization of these transcripts is described.

Insect densoviruses may be widespread in mosquito cell lines

A diagnostic PCR assay was designed based on conserved regions of previously sequenced densovirus genomic DNA isolated from mosquitoes. Application of this assay to different insect cell lines resulted in a number of cases of consistent positive amplification of the predicted size fragment. Positive PCR results were subsequently confirmed to correlate with densovirus infection by both electron microscopy and indirect fluorescent antibody test. In each case the nucleotide sequence of the amplified PCR fragments showed high identity to previously reported densoviruses isolated from mosquitoes. Phylogenetic analysis based on these sequences showed that two of these isolates were examples of new densoviruses. These viruses could infect and replicate in mosquitoes when administered orally or parenterally and these infections were largely avirulent. In one virus/mosquito combination vertical transmission to progeny was observed. The frequency with which these viruses were detected would suggest that they may be quite common in insect cell lines.

Biomolecular interaction analysis of IFN gamma-induced signaling events in whole-cell lysates: Prevalence of latent STAT1 in high-molecular weight complexes

The basic framework for the JAK/STAT pathway is well documented. Recruitment of latent cytoplasmic STAT transcription factors to tyrosine phosphorylated docking sites on cytokine receptors and their JAK-mediated phosphorylation instigates their translocation to the nucleus and their ability to bind DNA, The biochemical processes underlying recruitment and activation of this pathway have commonly been studied in reconstituted in vitro systems using previously defined recombinant signaling components. We have dissected the Interferon gamma (IFN gamma) signal transduction pathway in crude extracts from wild-type and STAT1-negative mutant cell Lines by real-time BIAcore analysis, size-exclusion (SE) chromatography and immune-detection. The data indicate that in detergent-free cell extracts: (1) the phospho-tyrosine (Y440P)-containing peptide motif of the IFN gamma-receptor ct-chain interacts directly with STAT1, or STAT1 complexes, and no other protein; (2) nonactivated STAT 1 is present in a higher molecular weight complex(es) and, at least for IFN gamma-primed cells, is available for recruitment to the activated IFN gamma-receptor from only a subset of such complexes; (3) activated STAT1 is released from the receptor as a monomer.

Algebraic Bethe ansatz for integrable Kondo impurities in the one-dimensional supersymmetric t-J model

An integrable Kondo problem in the one-dimensional supersymmetric t-J model is studied by means of the boundary supersymmetric quantum inverse scattering method. The boundary K matrices depending on the local moments of the impurities are presented as a nontrivial realization of the graded reflection equation algebras in a two-dimensional impurity Hilbert space. Further, the model is solved by using the algebraic Bethe ansatz method and the Bethe ansatz equations are obtained. (C) 1999 Elsevier Science B.V.

Integrable Kondo impurities in the one-dimensional supersymmetric U model of strongly correlated electrons

Integrable Kondo impurities in the one-dimensional supersymmetric U model of strongly correlated electrons are studied by means of the boundary graded quantum inverse scattering method. The boundary K-matrices depending on the local magnetic moments of the impurities are presented as non-trivial realizations of the reflection equation algebras in an impurity Hilbert space. Furthermore, the model Hamiltonian is diagonalized and the Bethe ansatz equations are derived. It is interesting to note that our model exhibits a free parameter in the bulk Hamiltonian but no free parameter exists on the boundaries. This is in sharp contrast to the impurity models arising from the supersymmetric t-J and extended Hubbard models where there is no free parameter in the bulk but there is a free parameter on each boundary.

Integrable Kondo impurities in the one-dimensional supersymmetric extended Hubbard model

An integrable Kondo problem in the one-dimensional supersymmetric extended Hubbard model is studied by means of the boundary graded quantum inverse scattering method. The boundary K-matrices depending on the local moments of the impurities are presented as a non-trivial realization of the graded reflection equation algebras in a two-dimensional impurity Hilbert space. Further, the model is solved by using the algebraic Bethe ansatz method and the Bethe ansatz equations are obtained.

Integrable Kondo impurities in one-dimensional extended Hubbard models

Three kinds of integrable Kondo problems in one-dimensional extended Hubbard models are studied by means of the boundary graded quantum inverse scattering method. The boundary K matrices depending on the local moments of the impurities are presented as a nontrivial realization of the graded reflection equation algebras acting in a (2s alpha + 1)-dimensional impurity Hilbert space. Furthermore, these models are solved using the algebraic Bethe ansatz method, and the Bethe ansatz equations are obtained.

Clinical profile of patients enroled in a cell therapy trial for severe coronary artery disease

Aims and objectives. To compare the clinical profile of patients included in a clinical trial of autologous bone marrow cells as an adjunctive therapy to coronary artery bypass grafting with that of patients undergoing routine coronary artery bypass grafting. Background. The therapeutic potential of autologous bone marrow cells has been explored in the treatment of severe coronary artery disease. There are few data regarding the clinical and socio-economic profile of patients included in clinical trials using bone marrow cell. Design. Case-control study. Method. Sixty-seven patients (61 SD 9) years, 82% men) with multivessel coronary artery disease were divided into two groups: patients in the bone marrow cell group (n = 34) underwent incomplete coronary artery bypass grafting + intramyocardial injection of autologous bone marrow cells (lymphomonocytic fraction -2.0 (SD 0.2 x 108) cells/patient) in the ischaemic, non-revascularised myocardium, whereas patients in the coronary artery bypass grafting group (n = 33) underwent routine bypass surgery. Demographics, socio-economic status, clinical and echocardiographic data were collected. Statistical analysis included the Fisher`s exact test (categorical variables) and the Student`s t-test (continuous variables). Results. There were no significant differences between groups regarding age, gender, BMI, heart rate, blood pressure and echo data. There was a greater prevalence of obesity (65 vs. 33%; OR = 3.7 [1.3-10.1]), of previous myocardial infarction (68 vs. 39%; OR = 3.2 [1.2-8.8]) and prior revascularisation procedures (59 vs. 24%; OR = 4.5 [1.6-12.7]) in the autologous bone marrow cells group and of smokers in the coronary artery bypass grafting group (51 vs. 23%; OR = 3.5 [1.2-10.4]). Conclusions. Patients included in this clinical trial of autologous bone marrow cells for severe coronary artery disease presented a greater prevalence of myocardial revascularisation procedures, indicating a more severe clinical presentation of the disease. Fewer smokers in this group could be attributable to life style changes after previous cardiovascular events and/or interventions. Relevance to clinical practice. The knowledge of the clinical profile of patients included in cell therapy trials may help researchers in the identification of patients that may be enroled in future clinical trials of this new therapeutic strategy.