Are plants with anti-cancer activity resistant to crown gall? : A test of hypothesis

The Crown gall tumour assay (CGTA) is one of several bench top bioassays recommended for the rapid screening of plants with anti-cancer activity. The rationale for the use of the bioassay is that the tumorogenic mechanism initiated in plant tissues by _Agrobacterium tumefaciens_ is in many ways similar to that of animals. Several plant species with anti-cancer activity have already been discovered using this bioassay. However till date no explicit test of an association between anti-cancer activity of plants and their resistance to crown gall formation has been demonstrated. Demonstration of an association could have exploratory potential when searching for plants with anti-cancer activity. In this paper, we determined whether or not a statistically significant association between crown gall resistance and anti-cancer activity exists in plants found in existing published data sets. Our results indicate that plants with anti-cancer activity have a higher proportion of their species resistant to crown gall formation compared to a random selection of plants. We discuss the implications of our results especially when prospecting for newer sources of anti-cancer activity in plants

Simulation of Three Dimensional Flows in Hydraulic Pumps

Hydraulic efficiency of the centrifugal pump is mainly depends on mass flow rate, Head and RPM. Finding the best combination with the above said parameters and the best geometry of the pump is possible by using three dimensional CFD simulations. For designers, prediction of operating characteristics curve is most important. All theoretical methods for prediction of efficiency merely give a value; but one is unable to determine the root cause for the poor performance. Due to the development of CFD code, one can get the efficiency value as well as observe actual behaviour. One can find the root cause for poor performance by using CFD Analysis of equipment. We have considered centrifugal pump for the three dimensional fluid flow analyses and validated the pump hydraulic efficiency with the experiment results. We observed the behaviour of the hydraulic efficiency with respect to the pump performance characteristics. Centrifugal pumps should be run at best efficiency point. Generally the radial force developed on the shaft will be high, if operates away from the BEP and it may leads to shaft damage. So it is important to find out best efficiency point

Use of Electronic Information Resources at College libraries in Bangalore, India: A Study of College Learners

This research article investigates the accessibility and usage of electronic resources among College libraries in Bangalore, Karnataka, India. In India, most of the institutions initiated electronic information resources in library services. Primary data were collected from four selected college libraries through a structured questionnaire method. Secondary data were collected from various national and international journals, various university libraries, books, magazines, newspapers, reports, etc. Besides, the websites and internet services of the institutions were also used for the purpose of secondary data collection. The result shows that the various e-resources, CD-ROM, e-newspaper, online database, full-text database, e-journal and e-books considered as the most importance e-resources by the respondents and 52.41% of the respondents very much satisfied with e-thesis and dissertation

Stylish lengths: Mate choice in flowers

The styles of flowers may represent an arena for pollen competition in the race to fertilize ovules. Accordingly, selection should favour a longer 'race' to better discriminate among variable pollen by increasing style length. Sampling across a taxonomically diverse range of wild and outcrossed species, we found that the distribution of style lengths within plants were skewed towards longer styles, as predicted. In self-pollinated domesticated species, where discrimination among pollen is less important, we found no such pattern. We conclude that style length is under directional selection towards longer styles as a mechanism for mate choice among pollen of variable quality

Genetic structure of the rattan Calamus thwaitesii in core, buffer and peripheral regions of three protected areas in central Western Ghats, India: do protected areas serve as refugia for genetic resources of economically important plants?

Given the increasing anthropogenic pressures on forests, the various protected areas-national parks, sanctuaries, and biosphere reserves-serve as the last footholds for conserving biological diversity. However, because protected areas are often targeted for the conservation of selected species, particularly charismatic animals, concerns have been raised about their effectiveness in conserving nontarget taxa and their genetic resources. In this paper, we evaluate whether protected areas can serve as refugia for genetic resources of economically important plants that are threatened due to extraction pressures. We examine the population structure and genetic diversity of an economically important rattan, Calamus thwaitesii, in the core, buffer and peripheral regions of three protected areas in the central Western Ghats, southern India. Our results indicate that in all the three protected areas, the core and buffer regions maintain a better population structure, as well as higher genetic diversity, than the peripheral regions of the protected area. Thus, despite the escalating pressures of extraction, the protected areas are effective in conserving the genetic resources of rattan. These results underscore the importance of protected areas in conservation of nontarget species and emphasize the need to further strengthen the protected-area network to offer refugia for economically important plant species

How promising are endophytic fungi as alternative sources of plant secondary metabolites?

In this article the authors discusses the use of endophytic fungi as substitute of plant secondary metabolites. It states that endophytic fungi exist internally in plants and enhance the plants' ability to tolerate abiotic and biotic stresses. Endophytic fungi if cultured outside their host can produce secondary metabolites such as anti-cancer, anti-fungal, anti-diabetic and immunosuppressant compounds

Prospecting for alternate sources of shikimic acid, a precursor of Tamiflu, a bird-flu drug

Shikimic acid, more commonly known by its anionic form, shikimate, is an important intermediate compound of the ‘shikimate pathway’ in plants and microorganisms1. It is the principal precursor for the synthesis of aromatic amino acids,phenylalanine, tryptophan and tyrosine and other compounds such as alkaloids, phenolics and phenyl propanoids2. It is used extensively as a chiral building block for the synthesis of a number of compounds in both pharmaceutical and cosmetic industries3. In the recent past, the focus on shikimic acid has increased since it is the key precursor for the synthesis of Tamiflu, the only drug against avian flu caused by the H5N1 virus4,5. Shikimic acid is converted to a diethyl ketal intermediate, which is then reduced in two steps to an epoxide that is finally transformed to Tamiflu6

Evaluation of third order nonlinear optical properties of SiO2/PVA-PEG Nanocomposites by Z-Scan Method

SiO2 nanoparticles was synthesized by sol-gel method and polymer nanocomposites by solvo-casting method. XRD and SEM analysis have revealed the size, morphological structure and formation of SiO2/PVA-PEG polymer nanocomposites. The presence of hydrogen bond between SiO2 and PVA-PEG was proved with the help of Fourier Transform Infra Red Spectroscopy (FTIR). Further UV-Vis studies was used to find the optical band gap and linear refractive index. Third order nonlinear optical properties such as two photon absorption, nonlinear refractive index and third order nonlinear susceptibility was evaluated for the title compound using Z-scan method. The estimated nonlinear optical properties of title compound proved the appropriateness of the sample for optical applications

Fetal Metabolic Adaptations to Cardiovascular Stress in Twin-Twin Transfusion Syndrome

Monochorionic-diamniotic twin pregnancies are susceptible to unique complications arising from a single placenta shared by two fetuses. Twin-twin transfusion syndrome (TTTS) is a constellation of disturbances caused by unequal blood flow within the shared placenta giving rise to a major hemodynamic imbalance between the twins. Here, we applied TTTS as a model to uncover fetal metabolic adaptations to cardiovascular stress. We compared untargeted metabolomic analyses of amniotic fluid samples from severe TTTS cases vs. singleton controls. Amniotic fluid metabolites demonstrated alterations in fatty acid, glucose, and steroid hormone metabolism in TTTS. Among TTTS cases, unsupervised principal component analysis revealed two distinct clusters of disease defined by levels of glucose metabolites, amino acids, urea, and redox status. Our results suggest that the human fetal heart can adapt to hemodynamic stress by modulating its glucose metabolism and identify potential differences in the ability of individual fetuses to respond to cardiovascular stress