Fuzzy estimator for plasmid-bearing microorganism

Fuzzy estimator is developed for determining the concentration of plasmid-bearing microorganism (x ⁺) in a continuous bioreactor. Membership functions, fuzzy ranges for the inputs and outputs are defined. A fuzzy rule base is constructed relating the inputs to the output based on operators experience. A defuzzification method is selected and the non-fuzzy value of x ⁺ is obtained. The results are compared with the actual values of x ⁺ which are obtained by numerically solving the model equations of the system. The estimator is also tested for the other operating conditions. The estimator performs well for other operating conditions also.     

Identification of differentially expressed sequences in pre-embryogenic tissue of oilseed rape by suppression subtractive hybridisation (SSH)

A subtracted cDNA library comprising of 576 clones were constructed to isolate differentially expressed sequences in the pre-embryogenic tissue (PEC) of winter oilseed repe. After differential screening, only 16 clones were identified as potential positives. Eventually, only three clones: BNPE DG3, BNPE AE4 and BNPE EG1 were confirmed by Northern analysis as upregulated in␣PEC of the oilseed rape embryogenic culture. This is the first study to report Ae4, Dg3 and Eg1 sequences as preferentially expressed in the oilseed␣rape PEC and associated with the induction of somatic embryogenesis in B.napus secondary embryogenesis. Ae4 encodes a putative proline-rich protein, Dg3 encodes a lipid transfer-like protein and Eg1 encodes a napin, member of the BNMNAP subfamily.     

Possible role of HIWI2 in modulating tight junction proteins in retinal pigment epithelial cells through Akt signaling pathway

PIWI subfamily of proteins is shown to be primarily expressed in germline cells. They maintain the genomic integrity by silencing the transposable elements. Although the role of PIWI proteins in germ cells has been documented, their presence and function in somatic cells remains unclear. Intriguingly, we detected all four members of PIWI-like proteins in human ocular tissues and somatic cell lines. When HIWI2 was knocked down in retinal pigment epithelial cells, the typical honeycomb morphology was affected. Further analysis showed that the expression of tight junction (TJ) proteins, CLDN1, and TJP1 were altered in HIWI2 knockdown. Moreover, confocal imaging revealed disrupted TJP1 assembly at the TJ. Previous studies report the role of GSK3β in regulating TJ proteins. Accordingly, phospho-kinase proteome profiler array indicated increased phosphorylation of Akt and GSK3α/β in HIWI2 knockdown, suggesting that HIWI2 might affect TJ proteins through Akt-GSK3α/β signaling axis. Moreover, treating the HIWI2 knockdown cells with wortmannin increased the levels of TJP1 and CLDN1. Taken together, our study demonstrates the presence of PIWI-like proteins in somatic cells and the possible role of HIWI2 in preserving the functional integrity of epithelial cells probably by modulating the phosphorylation status of Akt.     

Multifaceted role of tocotrienols in cardioprotection supports their structure: function relation

Tocotrienols are a class of vitamin E which modulates several mechanisms associated with cardioprotection, anti-cancer, anti-diabetic, and neuroprotection. Unlike other Vitamin E-like compounds, tocotrienols possess inimitable properties. Quite a lot of studies have determined the cardioprotective abilities of tocotrienols and have been shown to possess novel hypocholesterolemic effects together with an ability to reduce the atherogenic apolipoprotein and lipoprotein plasma levels. In addition, tocotrienol has been suggested to have an antioxidant, anti-thrombotic, and anti-tumor effect indicating that tocotrienol may serve as an effective agent in the prevention and/or treatment of cardiovascular disease and cancer. The bioactivity exhibited is due to the structural characteristics of tocotrienols. Rich sources of tocotrienols which include rice bran, palm oil, and other edible oils exhibit protective effect against cardiovascular disorders. The conclusions drawn from the early literature that vitamin E group of compounds provides an inevitable role in cardioprotection is sustained in many more recent studies.     

Isolation and characterization of precursors in bacteriophage T4 baseplate assembly. II. Purification of the protein products of genes 10 and 11 and the in vitro formation of the P(10/11) complex

Two bacteriophage T4 proteins which are precursors to the phage baseplate have been purified to homogeneity. These proteins, P10 and P11, are components of the P(10/11) complex, which is the first intermediate in the assembly of T4 baseplate 1/6th arms. Each protein was isolated from cells infected with a T4 amber mutant defective in the production of the other protein. Thus these purified proteins have never been assembled into the P(10/11) complex in vivo. Sodium dodecyl sulfate/polyacrylamide gel electrophoresis and the ability of these proteins to block the phage killing activity of specific antisera were used to monitor the purification steps. Sedimentation equilibrium experiments reveal a molecular weight of 188,000 g/mol for P10 and 60,000 g/mol for P11. These data together with the previously determined molecular weights of the gene 10 and gene 11 polypeptide chains (King & Mykolajewycz, 1973) and the in vivo assembled P(10/11) complex (Berget & King, 1978b) are consistent with P10 being a dimer of the product of gene 10, P11 being a dimer of the product of gene 11, and P(10/11) being a tetramer containing one of each of these dimers. Purified P10 and P11 are active in assembly because they complement 10- and 11- defective extracts, respectively, to form viable bacteriophage in vitro. Furthermore, these proteins assemble in vitro to form a protein structure identical to the P(10/11) complex formed in vivo as determined by non-denaturing gel electrophoresis. This P(10/11) complex formed in vitro complements 10-/11- defective extracts to form viable phage. The overall extent of this in vitro assembly reaction is not affected by NaCl to 1.5 M or 2% Triton X-100. The reaction is, however, prevented by the denaturing effects of urea and sodium dodecyl sulfate.     

Potential role of in vitro iron bioavailability studies in combatting iron deficiency: a study of the effects of phosvitin on iron mobilization from pinto beans

Iron deficiency and iron overload affect one billion people worldwide. Treatment of iron malnutrition can be enhanced by an understanding of iron bioavailability from the diet. We have focused on the development of in vitro methods for determining iron bioavailability in the hopes of providing both an understanding of the chemical basis leading to the inhibition or enhancement of iron absorption and the provision of methodologies which will allow nutritionists around the world to ascertain iron bioavailability of local foods and food combinations. The study reported here focuses on the effects of phosvitin, a suspected inhibitor of iron absorption found in egg yolks, on the chemistry of iron during the in vitro enzymatic digestion of pinto beans. Three basic types of information were obtained. First, the total soluble iron was determined during in vitro enzymatic digestion under simulated oral, gastric (pH 2) and duodenal (pH 6) conditions. Phosvitin was found to have a strong solubilizing effect at pH 6 and pH 2 when in the presence of ascorbate. Pyrophosphate also leads to high iron mobilization. A second approach is to determine the static Fe2+ and Fe3+ concentrations following in vitro enzymatic digestion of pinto beans at pH 2 and pH 6. Ascorbic acid enhanced the total soluble iron at both pH values, however, only at pH 2 was a large proportion of the iron found in the Fe2+ state and then only in the presence of phosvitin but not pyrophosphate. A third approach is to determine the amount of Fe2+ formed in the digestive supernatant during a 10-min incubation with ferrozine.(ABSTRACT TRUNCATED AT 250 WORDS)