An accurate comparative theoretical study of the interaction of furan,pyrrole, and thiophene with various gaseous analytes

An accurate comparison of the interaction of furan, pyrrole, and thiophene with different gaseous analytes is vital not only for understanding the sensing mechanism of corresponding polymers but also for rational design of new materials. In the present study, DFT calculations at (M05-2X/Aug-cc-PVDZ) have been performed to investigate the interaction behavior of furan, pyrrole, and thiophene (as models for their corresponding polymers) with different analytes (NH₃, CO₂, CO, N₂H₄, HCN, H₂O₂, H₂S, CH₄, CH₃OH, SO₂, SO₃, H₂O). The interaction of heterocycles with analytes is illustrated by changes in geometric, energetic, and electronic properties. SAPT calculations were performed for energy decomposition analysis to study the contribution of non-covalent components of the total interaction energy for each complex. Analysis of energetic and electronic properties reveals that all heterocycles are highly sensitive to SO₃. The results suggest that sensing ability of polypyrrole is higher than polyfuran and polythiophene for all analytes.

Open image in new window

Graphical abstract SAPT0 energies (kcal mol^-1) of furan, pyrrole, and thiophene with various gaseous analytes?

     

Synthesis of chiral pyrazolo[4,3-e][1,2,4]triazine sulfonamides with tyrosinase and urease inhibitory activity

A new series of sulfonamide derivatives of pyrazolo[4,3-e][1,2,4]triazine with chiral amino group has been synthesized and characterized. The compounds were tested for their tyrosinase and urease inhibitory activity. Evaluation of prepared derivatives demonstrated that compounds (8b) and (8j) are most potent mushroom tyrosinase inhibitors whereas all of the obtained compounds showed higher urease inhibitory activity than the standard thiourea. The compounds (8a), (8f) and (8i) exhibited excellent enzyme inhibitory activity with IC₅₀ 0.037, 0.044 and 0.042?μM, respectively, while IC₅₀ of thiourea is 20.9?μM.     

Invasive legumes can associate with many mutualists of native legumes,but usually do not

Mutualistic interactions can strongly influence species invasions, as the inability to form successful mutualisms in an exotic range could hamper a host's invasion success. This barrier to invasion may be overcome if an invader either forms novel mutualistic associations or finds and associates with familiar mutualists in the exotic range. Here, we ask (1) does the community of rhizobial mutualists associated with invasive legumes in their exotic range overlap with that of local native legumes and (2) can any differences be explained by fundamental incompatibilities with particular rhizobial genotypes? To address these questions, we first characterized the rhizobial communities naturally associating with three invasive and six native legumes growing in the San Francisco Bay Area. We then conducted a greenhouse experiment to test whether the invasive legume could nodulate with any of a broad array of rhizobia found in their exotic range. There was little overlap between the Bradyrhizobium communities associated with wild‐grown invasive and native legumes, yet the invasive legumes could nodulate with a broad range of rhizobial strains under greenhouse conditions. These observations suggest that under field conditions in their exotic range, these invasive legumes are not currently associating with the mutualists of local native legumes, despite their potential to form such associations. However, the promiscuity with which these invading legumes can form mutualistic associations could be an important factor early in the invasion process if mutualist scarcity limits range expansion. Overall, the observation that invasive legumes have a community of rhizobia distinct from that of native legumes, despite their ability to associate with many rhizobial strains, challenges existing assumptions about how invading species obtain their mutualists. These results can therefore inform current and future efforts to prevent and remove invasive species.     

Obesity and low back pain

Obesity and low back pain (LBP) are common health problems among patients attending Primary Health Care (PHC) in general practice at the United Arab Emirates (UAE). The objective of this study was to determine whether obesity is associated with low back pain. A cross-sectional face-to-face interview questionnaire survey was conducted. The questionnaire was a modified version of the Roland-Morris Scale for evaluating back disability. The interviews were conducted in Arabic by qualified nurses. A multi-stage stratified sample 1,103 UAE national aged 25-65 years, who attended PHC clinics for any reason, were invited to participate but only 802 subjects were eligible to be included for the statistical analysis. The data were analyzed using univariate and multivariate statistical methods. Of the 802 subjects, 428 (53.4%) were males and 374 (46.6%) were females. The mean age of the males was 40.5 +/- 11.5 years and females was 38.2 +/- 10.5 years (p = 0.004). The mean BMI of the males was 26.4 +/- 7.4 and females was 27.8 +/- 5.6 (p = 0.002). The overall prevalence of LBP in the present study was 64.9% (95% confidence interval, 61.0-68.8) and respectively, 56.1% in males and 73.8% in females. The results revealed that there was association between BMI and some socio-demographic variables with the respect of with low back pain. Back pain had more influence on the life style habits on females than in males. Stepwise multiple regression analysis showed that only age (p < 0.0001), educational level (p = 0.001), gender (p = 0.002), place of living (p = 0.019), BMI (p < 0.0001), and housing condition (p = 0.02) had significant effect on the presence of LBP in patients. The present study showed that obesity is moderately associated with low back pain.     

Method for determining oxygen consumption rates of static cultures from microplate measurements of pericellular dissolved oxygen concentration

The original article to which this Erratum refers was published in Biotechnol Bioeng 2004;86:775–787     

Potential role of glycosidase inhibitors in industrial biotechnological applications

The nutrient content of food and animal feed may be improved through new knowledge about enzymatic changes in complex carbohydrates. Enzymatic hydrolysis of complex carbohydrates containing alpha or beta glycosidic bonds is very important in nutrition and in several technological processes. These enzymes are called glycosidases (Enzyme Class 3.2.1) and include amylases, pectinases and xylanases. They are present in many foods such as cereals, but their microbial analogues are often produced and added in many food processes, for instance to improve the shelf-life of bakery products, clear beer, produce glucose, fructose or dextrins, hydrolyse lactose, modify food pectins, or improve processes. However, many plant foods also contain endogenous inhibitors, which reduce the activity of glycosidases, in particular, proteins, peptides, complexing agents and phenolic compounds. The plant proteinaceous inhibitors of glycosidases are in focus in this review whose objective is to report the effect and implications of these inhibitors in industrial processes and applications. These studies will contribute to the optimisation of industrial processes by using modified enzymes not influenced by the natural inhibitors. They will also allow careful selection of raw material and reaction conditions, and future development of new genetic varieties low in inhibitors. These are all new and very promising concepts for the food and feed sector.     

Compositional Quality and Possible Gastrointestinal Performance of Marketed Probiotic Supplements

Probiotics and Antimicrobial Proteins - The local pharmacies and shops are brimming with various probiotic products that herald a range of health benefits. The poor quality of probiotic products in...     

Assessment of mutagenicity induced by MMS and DES in Capsicum annuum L.

Seeds of Capsicum annuum L. var. G4 were subjected to different concentrations of methyl methane sulphonate (MMS) and diethyl sulphate (DES). The effects of different mutagenic treatments on meiosis, chiasma frequency, and pollen fertility have been studied in M₁ generation. Various types of meiotic aberrations such as univalent, multivalent, stickiness, bridge, laggards, cytomixis etc. were observed in all the treatments. However, the MMS treatments proved to be more effective in inducing meiotic aberrations as compared to DES. Moreover, the frequency of meiotic aberrations was at its maximum at metaphase followed by anaphase and telophase stages. As the concentrations increase, reduction in chiasma frequency and pollen fertility was observed in all the treatments and, MMS again was found to be more effective than DES treatments.     

Conditional Astroglial Rictor Overexpression Induces Malignant Glioma in Mice

Background

Hyperactivation of the mTORC2 signaling pathway has been shown to contribute to the oncogenic properties of gliomas. Moreover, overexpression of the mTORC2 regulatory subunit Rictor has been associated with increased proliferation and invasive character of these tumor cells.

Methodology/Principal Findings

To determine whether Rictor overexpression was sufficient to induce glioma formation in mice, we inserted a Cre-lox-regulated human Rictor transgene into the murine ROSA26 locus. This floxed Rictor strain was crossed with mice expressing the Cre recombinase driven from the glial fibrillary acidic protein (GFAP) promoter whose expression is limited to the glial cell compartment. Double transgenic GFAP-Cre/Rictor^loxP/loxP mice developed multifocal infiltrating glioma containing elevated mTORC2 activity and typically involved the subventricular zone (SVZ) and lateral ventricle. Analysis of Rictor-dependent signaling in these tumors demonstrated that in addition to elevated mTORC2 activity, an mTORC2-independent marker of cortical actin network function, was also elevated. Upon histological examination of the neoplasms, many displayed oligodendroglioma-like phenotypes and expressed markers associated with oligodendroglial lineage tumors. To determine whether upstream oncogenic EGFRvIII signaling would alter tumor phenotypes observed in the GFAP-Cre/Rictor^loxP/loxP mice, transgenic GFAP-EGFRvIII; GFAP-Cre/Rictor^loxP/loxP mice were generated. These mice developed mixed astrocytic-oligodendroglial tumors, however glioma formation was accelerated and correlated with increased mTORC2 activity. Additionally, the subventricular zone within the GFAP-Cre/Rictor^loxP/loxP mouse brain was markedly expanded, and a further proliferation within this compartment of the brain was observed in transgenic GFAP-EGFRvIII; GFAP-Cre/Rictor^loxP/loxP mice.

Conclusion/Significance

These data collectively establish Rictor as a novel oncoprotein and support the role of dysregulated Rictor expression in gliomagenesis via mTOR-dependent and mTOR-independent mechanisms. Furthermore, oncogenic EGFRvIII signaling appears to potentiate the in vivo proliferative capacity of GFAP-Cre/Rictor^loxP/loxP gliomas.