Receptor for advanced glycation end products (RAGE) soluble form (sRAGE): a new biomarker for lung cancer

Receptor for advanced glycation end products (RAGE) may be involved in the pathogenesis of cancer progression. Pathological effects mediated via RAGE are physiologically inhibited by soluble RAGE (sRAGE). The aim of this study was to identify sRAGE and RAGE expression profile in lung cancer patients. An ELISA method was used to quantify serum sRAGE in 45 individuals. Additionally, surgical specimens of 28 lung cancer patients were also included for RAGE expression by immunohistochemistry. Serum sRAGE was significantly decreased in lung cancer patients compared with controls (vs. healthy donors, P=0.034; vs. pulmonary tuberculosis patients, P=0.010). Lower sRAGE concentration was negative correlated with lymph node involvement (N0 vs. N1-2, P=0.028). Down regulation of membranous and cytoplasmic expression for RAGE was also lower in lung cancer tissue than in nearby normal lung tissue. Correlation with serum sRAGE concentration and RAGE expression in lung cancer tissue was existed by CV values. The results indicate that serum sRAGE levels are decreased during lung cancer progression and could reflect decreased RAGE expression in tissue. Serum sRAGE may serve as an effective and convenient diagnostic biomarker for lung cancer.

KEYWORDS

sRAGE, serum, RAGE, tissue, lung cancer.

Allergen challenge of peripheral blood mononuclear cells from patients with seasonal allergic rhinitis increases IL-17RB, which regulates basophil apoptosis and degranulation

BACKGROUND

Previously, expression profiling has been used to analyse allergen-challenged T-helper type 2 cells, nasal biopsies and nasal fluid cells from patients with seasonal allergic rhinitis (SAR). Allergen-challenged peripheral blood mononuclear cells (PBMCs) provide a human in vitro model of how antigen-presenting cells, CD4+ T cells and effector cells such as basophils interact in allergic inflammation.

OBJECTIVE

To identify novel genes and pathways in allergen-challenged PBMCs from patients with SAR using gene expression profiling and functional studies.

METHODS

PBMCs from 11 patients with SAR and 23 healthy controls were analysed with gene expression profiling. mRNA expression of IL17RB in basophils was evaluated using quantitative real-time PCR. Membrane protein expression and apoptosis of basophils were examined by flow cytometry. Degranulation of basophils was assessed by measuring beta-hexosaminidase release. Cytokine release was measured using ELISA.

RESULTS

Gene expression microarray analysis of allergen-challenged PBMCs showed that 209 out of 44000 genes were differentially expressed in patients compared with controls. IL17RB was the gene whose expression increased most in patients (P<0.0001). FACS analysis of PBMCs showed, for the first time, that basophils express IL-17RB. Following allergen challenge, IL-17RB protein increased significantly on basophils from patients compared with controls (P<0.05). IL-3 significantly increased both mRNA and protein expressions of IL17RB. Activation of IL-17RB by its ligand, IL-25, inhibited apoptosis of basophils. Moreover, IgE-mediated degranulation was enhanced by IL-25.

CONCLUSION

Increased expression of IL-17RB on allergen-challenged basophil is regulated by IL-3, inhibits apoptosis and promotes IgE-mediated degranulation of basophils.

Genomic polymorphisms within alpha 7 nicotinic acetylcholine receptor and severe sepsis in Chinese Han population

Alpha 7 nicotinic acetylcholine receptor, a kind of ligand-gated ion channel mainly expressed in macrophages, plays a crucial role in improving survival in sepsis via suppressing proinflammatory cytokines. The predisposition of genomic polymorphisms within alpha 7 nicotinic acetylcholine receptor gene (CHRNA7) to sepsis has not been investigated. The current association study was performed to analyse six common genetic variations within 5'-upstream region of CHRNA7 gene in 229 patients with severe sepsis and 267 controls. Neither allelic frequencies nor genotype distributions were significantly different between patients and controls, as well as between surviving and nonsurviving patients. The frequencies of estimated haplotypes were also comparable between above defined groups. The present study suggests that genomic polymorphisms in the 5'-upstream region of CHRNA7 gene may not be a major risk factor for severe sepsis in Chinese Han population.

Ozone-surface reactions in five homes: surface reaction probabilities, aldehyde yields, and trends

Field experiments were conducted in five homes during three seasons (summer 2005, summer 2006 and winter 2007) to quantify ozone-initiated secondary aldehyde yields, surface reaction probabilities, and trends any temporal over a 1.5-year interval. Surfaces examined include living room carpets, bedroom carpets, kitchen floors, kitchen counters, and living room walls. Reaction probabilities for all surfaces for all seasons ranged from 9.4 x 10(-8) to 1.0 x 10(-4). There were no significant temporal trends in reaction probabilities for any surfaces from summer 2005 to summer 2006, nor over the entire 1.5-year period, indicating that it may take significantly longer than this period for surfaces to exhibit any 'ozone aging' or lowering of ozone-surface reactivity. However, all surfaces in three houses exhibited a significant decrease in reaction probabilities from summer 2006 to winter 2007. The total yield of aldehydes for the summer of 2005 were nearly identical to that for summer of 2006, but were significantly higher than for winter 2007. We also observed that older carpets were consistently less reactive than in newer carpets, but that countertops remained consistently reactive, probably because of occupant activities such as cooking and cleaning.

PRACTICAL IMPLICATIONS

Ozone reactions taking place at indoor surfaces significantly influence personal exposure to ozone and volatile reaction products. These field studies show that indoor surfaces only slowly lose their ability to react with ozone over several year time frames, and that this is probably because of a combination of large reservoirs of reactive coatings and periodic additions of reactive coatings in the form of cooking, cleaning, and skin-oil residues. When considering exposure to ozone and its reaction products and in the absence of dramatic changes in occupancy, activities or furnishings, indoor surface reactivity is expected to change very slowly.

Optimal pulmonary artery perfusion mode and perfusion pressure during cardiopulmonary bypass

AIM

Reducing lung injury during cardiopulmonary bypass (CPB) is important for patients' recovery. The present study was designed to evaluate the effects of pulmonary artery perfusion pressure on the extent of lung injury during CPB in an animal model.

METHODS

Twenty healthy mongrel dogs were randomly divided into four groups, including a control group and three perfusion groups designed to simulate clinical cardiopulmonary bypass-induced lung injury. During pulmonary ischemia and cardiopulmonary bypass, protective perfusions were performed using different perfusion pressures (15-20, 25-30, and 40-45 mmHg), while animals in the control group were not perfused. After pulmonary reperfusion, the changes in pulmonary function and tissue histopathology were determined.

RESULTS

Compared with the control group, lung compliance, oxygenation and vascular resistance after reperfusion were significantly improved in both low- and moderate-pressure groups. The malonaldehyde concentration, neutrophil sequestration ratio, and expression of ICAM-1 were also decreased significantly in the two groups. However, there were no significant differences in any of these parameters between the control group and the high-pressure group. Histopathological examination demonstrated that there were obvious inflammatory cell infiltration and tissue damage in the control and high-pressure groups, which was prevented in the low- and moderate-pressure groups.

CONCLUSION

The perfusion pressure is an important factor that determines the extent of lung protection, and the use of pressures below 30 mmHg is optimal, with the safest and most effective range being 15-20 mmHg.

Influence of the type of indigestible carbohydrate on plasma and urine short-chain fatty acid profiles in healthy human volunteers

BACKGROUND/OBJECTIVES

Health effects of whole grain foods are becoming more evident. In this study, we analysed the short-chain fatty acid profiles in urine and serum derived from the colonic fermentation process of (13)C-barley meals, prepared from barley grown under (13)CO(2) atmosphere.

SUBJECTS/METHODS

In a crossover study, five volunteers ingested intact barley kernels (high content of non-starch polysaccharides (NSP) and resistant starch (RS)) and barley porridge (high content of NSP only). Using a newly developed stable isotope technology, we monitored 14 and 24 h postprandially (13)C-acetate, (13)C-propionate and (13)C-butyrate in plasma and urine, respectively. The oro-cecal transit time (OCTT) of the meals was measured with the hydrogen breath test.

RESULTS

The OCTT was 6 h and did not differ between the two test meals. An increase of (13)C-acetate was observed already early after ingestion of the meals (<6 h) and was attributed to early fermentation of the test meal. A rise in plasma (13)C-propionate in the fermentation phase could only be detected after the porridge and not after the kernel meal. An increase in (13)C-butyrate was only found in the fermentation phase and was higher after the barley kernels. Urine (13)C-short-chain fatty acids data were consistent with these observations.

CONCLUSIONS

The difference in the profiles of (13)C-acetate, (13)C-propionate and (13)C-butyrate indicates that NSP combined with RS results in an altered fermentation profile than dietary fibre alone.

Inference of gene regulatory networks using S-system: a unified approach

With the increased availability of DNA microarray time-series data, it is possible to discover dynamic gene regulatory networks (GRNs). S-system is a promising model to capture the rich dynamics of GRNs. However, owing to the complexity of the inference problem and limited number of available data comparing to the number of unknown kinetic parameters, S-system can only be applied to a very small GRN with few parameters. This significantly limits its applications. A unified approach to infer GRNs using the S-system model is proposed. In order to discover the structure of large-scale GRNs, a simplified S-system model is proposed that enables fast parameter estimation to determine the major gene interactions. If a detailed S-system model is desirable for a subset of genes, a two-step method is proposed where the range of the parameters will be determined first using genetic programming and recursive least square estimation. Then the mean values of the parameters will be estimated using a multi-dimensional optimisation algorithm. Both the downhill simplex algorithm and modified Powell algorithm are tested for multi-dimensional optimisation. A 50-dimensional synthetic model with 51 parameters for each gene is tested for the applicability of the simplified S-system model. In addition, real measurement data pertaining to yeast protein synthesis are used to demonstrate the effectiveness of the proposed two-step method to identify the detailed interactions among genes in small GRNs.

Denosumab-mediated increase in hand bone mineral density associated with decreased progression of bone erosion in rheumatoid arthritis patients

OBJECTIVE

Periarticular osteoporosis is one of the earliest radiographic signs of bone damage in rheumatoid arthritis (RA). Denosumab, an investigational fully human monoclonal antibody that binds to RANKL, inhibits bone erosion and systemic bone loss in clinical studies of patients with RA. In this hand bone mineral density (BMD) substudy, we investigated the effects of denosumab on hand BMD and its correlation with hand erosion scores.

METHODS

Patients receiving methotrexate for erosive RA were randomized in a 1:1:1 ratio to receive subcutaneous placebo, denosumab 60 mg, or denosumab 180 mg at 0 and 6 months. Measurements included BMD (by dual x-ray absorptiometry [DXA]) of both hands (0, 1, 6, and 12 months), magnetic resonance images of the hands/wrists (0 and 6 months), and radiographs of the hands/wrists and feet (0, 6, and 12 months).

RESULTS

There were 56 patients (13 placebo, 21 denosumab 60 mg, and 22 denosumab 180 mg). Mean changes in hand BMD at 6 and 12 months were: +0.8% and +1.0%, respectively, for denosumab 60 mg; +2.0% and +2.5%, respectively, for denosumab 180 mg; and -1.2% and -2.0%, respectively, for placebo. Erosion scores remained near baseline in the denosumab groups and increased from baseline in the placebo group. A negative correlation was observed between hand BMD and erosion scores.

CONCLUSION

In patients with RA, denosumab provided protection against erosion, and not only prevented bone loss but increased hand BMD as measured by DXA.

Cytoplasmic tails of hantavirus glycoproteins interact with the nucleocapsid protein

Here we characterize the interaction between the glycoproteins (Gn and Gc) and the ribonucleoprotein (RNP) of Puumala virus (PUUV; genus Hantavirus, family Bunyaviridae). The interaction was initially established with native proteins by co-immunoprecipitating PUUV nucleocapsid (N) protein with the glycoprotein complex. Mapping of the interaction sites revealed that the N protein has multiple binding sites in the cytoplasmic tail (CT) of Gn and is also able to bind to the predicted CT of Gc. The importance of Gn- and Gc-CTs to the recognition of RNP was further verified in pull-down assays using soluble peptides with binding capacity to both recombinant N protein and the RNPs of PUUV and Tula virus. Additionally, the N protein of PUUV was demonstrated to interact with peptides of Gn and Gc from a variety of hantavirus species, suggesting a conserved RNP-recognition mechanism within the genus. Based on these and our previous results, we suggest that the complete hetero-oligomeric (Gn-Gc)(4) spike complex of hantaviruses mediates the packaging of RNP into virions.