From oligomers to molecular giants of soybean oil in supercritical carbon dioxide medium: 1. Preparation of polymers with lower molecular weight from soybean oil

Polymers with a low molecular weight derived from soybean oil have been prepared in a supercritical carbon dioxide medium by cationic polymerization. Boron trifluoride diethyl etherate was used as an initiator. Influences of polymerization temperature, amount of initiator, and carbon dioxide pressure on the molecular weight were investigated. It is shown that the higher polymerization temperature favors polymers with relatively higher molecular weights. Larger amounts of initiator also provide polymers with higher molecular weights. Higher pressure favors polymers with relatively higher molecular weights. The applications of these soy-based materials will be in the lubrication and hydraulic fluid areas.     

Indian Science Culture Needs a Paradigm Shift

There is a general impression in the scientific community in our country that the way science is taught, leant and the work culture of research and management of academic and research institutions is not conducive to cutting edge research, innovation and making world leaders. Mentoring continues to be poor with some exceptions. Very often, senior scientists with long innings in science teaching and research express anguish at the status quo in spite of a number of policy documents and recommendations for change. Indian science culture (teaching, research as well as administration) is a matter of prime concern and the issues cannot be pushed under the carpet if we desire a qualitative change. Most of the institutions of higher learning churn out graduates and post graduates who are largely unemployable. There are concerns on the number of Ph.Ds and not on the quality of Ph.D. One major consequence of the weak post graduates and Ph.Ds is the non-availability of competent faculty. Weakness and lack of interest in science learning starts from school. Learning continues to be by rote which is the prime reason for our low global rank in science and mathematics competence. Teaching and research apart there are umpteen other issues in over all culture of institutions and universities engaged in science teaching and research. Few oases of excellence are exceptions in the vast pool of mediocrity. Some points which need prime attention are: adoption of a tenure track system on the pattern of US institutions; feedback on and evaluation of teaching and mentoring; bottom up approach for candid feedback on issues which require long term solutions for efficiency and sound deliverables, cultivating the culture of working in front line areas, full transparency in working and an all out exit from culture of feudalism. This transformation needs commitment on the part of the politicians who man the respective departments of science education, research and human resource development. I am sure such a cultural change and paradigm shift from the status quo does not need extra funds and can be surely ushered in without money.     

Discovery of conformationally rigid 3-azabicyclo[3.1.0]hexane-derived dipeptidyl peptidase-IV inhibitors

The induction of conformationally restricted N-(aryl or heteroaryl)-3-azabicyclo[3.1.0]hexane derivatives at P₂ region of compounds of 2-cyanopyrrolidine class was explored to develop novel DPP-IV inhibitors. The synthesis, structure–activity relationship, and selectivity against related proteases are delineated.     

Speed Breeding Opportunities and Challenges for Crop Improvement

Journal of Plant Growth Regulation - Crop improvement in light of the rapidly changing climate and the increasing human population continues to be one of the primary concerns for researchers across...     

A fusion gene coding for two different δ-endotoxinsof Bacillus thuringiensis toxic to Plutella xylostella and usefulfor resistance management

Two truncated Bacillus thuringiensis -endotoxin genes, belonging to the classes cry1Ab and cry1B, and both coding for N-terminal toxic fragments of the corresponding crystal proteins, were translationally fused. Expression of the fusion gene driven by the cry1C promoter in Escherichia coli at a very high level resulted in a protein with enhanced toxicity to the diamondback moth (Plutella xylostella).     

Synthesis, modification with N-acetoxy-2-acetylaminofluorene and physicochemical studies of DNA model compound d(TACGTA)

The deoxyhexanucleotide d(TACGTA) was synthesized by a modified phosphotriester method. The modified procedure made rapid synthesis of deoxyoligonucleotide possible in gram quantity. N-Acetoxy-2-acetylaminofluorene (AAAF) modified d(TACGTA). Thin layer chromatography and UV analysis of the acid treated AAF modified hexanucleotide showed that the covalent modification with AAF took place exclusively at C(8) of guanine in d(TACGTA). d(TACGTA) and AAF modified d(TACGTA) were purified by preparative high performance liquid chromatography (HPLC). The pure products were characterized by 1H and 31P-NMR. The circular dichroism (CD) spectrum of d(TACGTA) was consistent with DNA in the B form even in the presence of 4 M NaCl whereas the modified hexamer had nearly inverted spectrum in the absence of any added salt. Both NMR and CD analyses indicated profound alteration of conformation of d(TACGTA) upon covalent modification with AAF. The stabilization of the Z-like conformation in the modified hexamer under physiological conditions of salt and temperature suggests biological relevance.     

Anti-inflammatory activity of shikonin derivatives from Arnebia hispidissima.

Arnebia hispidissima ethanolic extract, after chromatography, yielded a number of shikonin derivatives, which were identified as arnebin-5, arnebin-6, teracryl shikonin, arnebinone and acetyl shikonin. All these compounds were firstly reported from this plant species and evaluated to the anti-inflammatory activity of ethanolic extract and isolated shikonin derivatives, models with carrageenan-induced paw edema and complete Freund's adjuvant (CFA)-induced chronic arthritis in rats were conducted. The observed results indicated that pre-treatment with arnebinone significantly inhibited the carrageenan-induced paw edema and also suppressed the development of chronic arthritis induced by CFA.     

Curcumin Suppresses Gelatinase B Mediated Norepinephrine Induced Stress in H9c2 Cardiomyocytes

Background

Extracellular matrix (ECM) remodeling facilitates biomechanical signals in response to abnormal physiological conditions. This process is witnessed as one of the major effects of the stress imposed by catecholamines, such as epinephrine and norepinephrine (NE), on cardiac muscle cells. Matrix metalloproteinases (MMPs) are the key proteases involved in degradation of the ECM in heart.

Objectives

The present study focuses on studying the effect of curcumin on Gelatinase B (MMP-9), an ECM remodeling regulatory enzyme, in NE-induced cardiac stress. Curcumin, a bioactive polyphenol found in the spice turmeric, has been studied for its multi-fold beneficial properties. This study focuses on investigating the role of curcumin as a cardio-protectant.

Methods

H9c2 cardiomyocytes were subjected to NE and curcumin treatments to study the response in stress conditions. Effect on total collagen content was studied using Picrosirus red staining. Gelatinase B activity was assessed through Gel-Diffusion Assay and Zymographic techniques. RT-PCR, Western Blotting and Immunocytochemistry were performed to study effect on expression of gelatinase B. Further, the effect of curcumin on the localization of NF-κB, known to regulate gelatinase B, was also examined.

Results

Curcumin suppressed the increase in the total collagen content under hypertrophic stress and was found to inhibit the in-gel and in-situ gelatinolytic activity of gelatinase B. Moreover, it was found to suppress the mRNA and protein expression of gelatinase B.

Conclusions

The study provides an evidence for an overall inhibitory effect of curcumin on Gelatinase B in NE-induced hypertrophic stress in H9c2 cardiomyocytes which may contribute in the prevention of ECM remodeling.     

Evaluation of Salmonella Porins as a Broad Spectrum Vaccine Candidate

Porins were prepared from smooth strain of Salmonella typhi 0–901 and chemotype of rough mutant of S. typhimurium Ra-30. Mice were immunized with both the porin preparations in different groups and challenged with S. typhimurium LT2–71 and S. enteritidis SH-1269. Porin immunized mice showed significant protection (P <0.01) against challenge with homologous as well as heterologous strains. Hence, the use of porins may be attempted in future to protect against salmonellosis.