Leaf anatomy as an additional taxonomy tool for 18 taxa of Matricaria L. and Tripleurospermum Sch. Bip. (Anthemideae-Asteraceae) in Turkey

This study concerns the evaluation of leaf anatomical characteristics of the closely related genera Matricaria (4 taxa) and Tripleurospermum (14 endemic taxa, 15 accessions) in Turkey using cluster analysis (CA) and principal component analysis (PCA). All taxa have the same basic leaf structure composed of lower and upper epidermis including anomocytic or anomocytic-anisocytic stomata, parenchymatic mesophyll, and vascular bundle. Statistically significant differences based on ploidy level have been found without generic delimitation. The differences mainly concern stomatal length and the relative size of the vascular bundle. These anatomical characters can be used to distinguish diploid from polyploid taxa of the genera.     

Impaired Clearance of Influenza A Virus in Obese,Leptin Receptor Deficient Mice Is Independent of Leptin Signaling in the Lung Epithelium and Macrophages

Rationale

During the recent H1N1 outbreak, obese patients had worsened lung injury and increased mortality. We used a murine model of influenza A pneumonia to test the hypothesis that leptin receptor deficiency might explain the enhanced mortality in obese patients.

Methods

We infected wild-type, obese mice globally deficient in the leptin receptor (db/db) and non-obese mice with tissue specific deletion of the leptin receptor in the lung epithelium (SPC-Cre/LepR^fl/fl) or macrophages and alveolar type II cells (LysM-Cre/Lepr^fl/fl) with influenza A virus (A/WSN/33 [H1N1]) (500 and 1500 pfu/mouse) and measured mortality, viral clearance and several markers of lung injury severity.

Results

The clearance of influenza A virus from the lungs of mice was impaired in obese mice globally deficient in the leptin receptor (db/db) compared to normal weight wild-type mice. In contrast, non-obese, SP-C-Cre^+/+/LepR^fl/fl and LysM-Cre^+/+/LepR^fl/fl had improved viral clearance after influenza A infection. In obese mice, mortality was increased compared with wild-type mice, while the SP-C-Cre^+/+/LepR^fl/fl and LysM-Cre^+/+/LepR^{fl /fl} mice exhibited improved survival.

Conclusions

Global loss of the leptin receptor results in reduced viral clearance and worse outcomes following influenza A infection. These findings are not the result of the loss of leptin signaling in lung epithelial cells or macrophages. Our results suggest that factors associated with obesity or with leptin signaling in non-myeloid populations such as natural killer and T cells may be associated with worsened outcomes following influenza A infection.     

Decreased Serum Level of miR-146a as Sign of Chronic Inflammation in Type 2 Diabetic Patients

Background

There is increasing evidence that chronic inflammation is an important determinant in insulin resistance and in the pathogenesis of type 2 diabetes (T2D). MicroRNAs constitute a newly discovered system of cell regulation and in particular two microRNAs (miR-146a and miR-155) have been described as regulators and biomarkers of inflammation.

Aim

To determine a putative association between the levels of miR-146a and miR-155 in serum of T2D patients, clinical parameters and serological indicators of inflammation.

Methods

We performed quantitative Real Time PCR (qPCR) of microRNAs from serum (56 Ecuadorian T2D ambulatory patients and 40 non-diabetic controls). In addition, we evaluated T2D-related serum cytokines.chemokines and growth factors using a commercially available multi-analyte cytometric bead array system. We correlated outcomes to clinical parameters, including BMI, HbA1c and lipid state.

Results

The Ecuadorian non-diabetic controls appeared as overweight (BMI>25: patients 85%, controls 82.5%) and as dyslipidemic (hypercholesterolemia: patients 60.7%, controls 67.5%) as the patients.

• The serum levels of miR-146a were significantly reduced in T2D patients as compared to these non-diabetic, but obese/dyslipidemic control group (mean patients 0.61, mean controls set at 1; p = 0.042), those of miR-155 were normal.
• The serum levels of both microRNAs correlated to each other (r = 0.478; p<0.001) and to leptin levels. The microRNAs did not correlate to BMI, glycemia and dyslipidemia.
• From the tested cytokines, chemokines and growth factors, we found IL-8 and HGF significantly raised in T2D patients versus non-diabetic controls (p = 0.011 and 0.023 respectively).

Conclusions

This study shows decreased serum anti-inflammatory miR-146a, increased pro-inflammatory IL-8 and increased HGF (a vascular/insular repair factor) as discriminating markers of failure of glucose control occurring on the background of obesity and dyslipidemia.     

Discovery of PI-1840, a Novel Noncovalent and Rapidly Reversible Proteasome Inhibitor with Anti-tumor Activity

The proteasome inhibitor bortezomib is effective in hematologic malignancies such as multiple myeloma but has little activity against solid tumors, acts covalently, and is associated with undesired side effects. Therefore, noncovalent inhibitors that are less toxic and more effective against solid tumors are desirable. Structure activity relationship studies led to the discovery of PI-1840, a potent and selective inhibitor for chymotrypsin-like (CT-L) (IC₅₀ value = 27 ± 0.14 nm) over trypsin-like and peptidylglutamyl peptide hydrolyzing (IC₅₀ values >100 μm) activities of the proteasome. Furthermore, PI-1840 is over 100-fold more selective for the constitutive proteasome over the immunoproteasome. Mass spectrometry and dialysis studies demonstrate that PI-1840 is a noncovalent and rapidly reversible CT-L inhibitor. In intact cancer cells, PI-1840 inhibits CT-L activity, induces the accumulation of proteasome substrates p27, Bax, and IκB-α, inhibits survival pathways and viability, and induces apoptosis. Furthermore, PI-1840 sensitizes human cancer cells to the mdm2/p53 disruptor, nutlin, and to the pan-Bcl-2 antagonist BH3-M6. Finally, in vivo, PI-1840 but not bortezomib suppresses the growth in nude mice of human breast tumor xenografts. These results warrant further evaluation of a noncovalent and rapidly reversible proteasome inhibitor as potential anticancer agents against solid tumors.     

Molecularly imprinted ligand-exchange recognition assay of glucose by quartz crystal microbalance

Molecular imprinted polymers (MIP) as a recognition element for sensors are increasingly of interest and MIP-quartz crystal microbalance (QCM) have started to appear in the literature. In this study, we have combined quartz crystal microbalance with MIP to prepare a sensor using the ability of glucose to chelate of copper (II) ion of methacrylamidohistidine (MAH) monomer to create ligand exchange (LE) assembled monolayer which is suitable for glucose determination. The study includes the measurement of binding interaction of molecularly imprinted QCM sensor via ligand interaction, investigation of the pH effect on frequency shift and recognition selectivity studies of glucose-imprinted polymer with respect to methyl-alpha-d-glucopyranoside and sucrose. Bmax (number of binding sites) and K(D) (dissociation constant of the metal-chelate copolymer) were also calculated using Scathard plot and the detection limit was found as 0.07 mM. MIP showed higher glucose-binding affinity than a well-known glucose binding protein, conconavalin A.     

Ras oncogene mutations in urine sediments of patients with bladder cancer

Early detection of bladder cancer is particularly important since it dramatically affects the survival rates. However, neither urinary cytology nor tumor markers that are currently used are sensitive enough for the early detection of bladder cancer or recurrent disease. The ras genes are frequently mutated in cancer. In this study, we investigated the diagnostic potential of ras mutation analysis in urinary sediments of patients with bladder cancer using a single-strand conformation polymorphism analysis and polymerase chain reaction. Mutation in codon 12 of the H-ras gene was observed in 39% of the patients. Our results indicate that this approach may significantly improve diagnostic sensitivity in detecting bladder tumors.     

Modelling the Effects of Debranching and Microwave Irradiation Treatments on the Properties of High Amylose Corn Starch by Using Response Surface Methodology

Response surface methodology was applied to determine the effects of pullulanase debranching, microwave irradiation time (2–4 min) and power (20–100%) on resistant starch (RS) formation and in-vitro glycemic index (GI) values in high amylose corn starch, Hylon VII. Starch:water (1:10) suspensions were cooked and autoclaved, debranched with pullulanase (1000 PUN/g; 1500 U/kg starch) at 60 °C and then different microwave-storing cycles and drying (oven or freeze drying) processes were applied. In order to describe the relationship between the dependent and independent variables (microwave power and irradiation time), the response values were fitted by first order polynomial regression models. Significance analysis showed that microwave irradiation time had significant effect on RS content and GI value of the samples treated with one cycle of microwave-storing prior to freeze-drying. Microwave power had significant factor on the GI value of the samples that were oven-dried after one cycle of microwave-storing. Solubility and water binding capacity values of all heat treated samples were higher than those of native starch. On the other hand, RVA viscosity values were lower than native starch for oven-dried samples. Water binding capacity, solubility and final viscosity values of the freeze-dried samples were higher than those of oven-dried ones.     

Cloning of a cellulase gene from the rumen anaerobe Fibrobacter succinogenes SD35 and partial characterization of the gene product

N. OZCAN, C. CUNNINGHAM AND W.J. HARRIS. 1996. A gene encoding an enzyme which degrades cellulose ( end-1 ) was isolated from a library of Fibrobacter succinogenes SD35 DNA fragments and expressed in pUC18. The product of end-1 showed significant activity against carboxymethylcellulose but relatively minor activity against lichenan, xylan and avicel. The nucleotide sequence indicated a product of 388 amino acids with a molecular mass of 50.2 kDa. This was in agreement with the molecular size estimated by gel electrophoresis. No significant DNA sequence similarity was identified with any published endoglucanase.