The comparative effects of metals on the hatching of earthworm cocoons

To establish the use of Metaphire posthuma as a sensitive model for ecotoxicological studies, the comparative effects of five metals on the hatching profiles of the cocoons of the earthworms, Metaphire posthuma, Eisenia foetida and Perionyx excavatus, were studied. The cocoons of the three species of earthworms were exposed to copper, chromium (III), chromium (VI), lead and zinc at 1.25, 2.5, 5.0 and 10.0 ppm. Viable cocoons were incubated at 20 +/- degrees C by using the immersion method. The results indicated that the inhibition of cocoon hatching was concentration dependent. The normal hatching, delayed hatching and non-viability of cocoons were recorded. At a concentration of 1.25 ppm, there was almost no effect on the hatching of the cocoons of all three species of earthworms, except when exposed to chromium (VI), but higher concentrations (2.5 and 5.0 ppm) caused severe effects. It was concluded that M. posthuma was more sensitive than the other two species, and that it is a suitable model for use in ecotoxicity testing.     

Tryptamine-gallic acid hybrid prevents non-steroidal anti-inflammatory drug-induced gastropathy: correction of mitochondrial dysfunction and inhibition of apoptosis in gastric mucosal cells

We have investigated the gastroprotective effect of SEGA (3a), a newly synthesized tryptamine-gallic acid hybrid molecule against non-steroidal anti-inflammatory drug (NSAID)-induced gastropathy with mechanistic details. SEGA (3a) prevents indomethacin (NSAID)-induced mitochondrial oxidative stress (MOS) and dysfunctions in gastric mucosal cells, which play a pathogenic role in inducing gastropathy. SEGA (3a) offers this mitoprotective effect by scavenging of mitochondrial superoxide anion (O(2)(·-)) and intramitochondrial free iron released as a result of MOS. SEGA (3a) in vivo blocks indomethacin-mediated MOS, as is evident from the inhibition of indomethacin-induced mitochondrial protein carbonyl formation, lipid peroxidation, and thiol depletion. SEGA (3a) corrects indomethacin-mediated mitochondrial dysfunction in vivo by restoring defective electron transport chain function, collapse of transmembrane potential, and loss of dehydrogenase activity. SEGA (3a) not only corrects mitochondrial dysfunction but also inhibits the activation of the mitochondrial pathway of apoptosis by indomethacin. SEGA (3a) inhibits indomethacin-induced down-regulation of bcl-2 and up-regulation of bax genes in gastric mucosa. SEGA (3a) also inhibits indometacin-induced activation of caspase-9 and caspase-3 in gastric mucosa. Besides the gastroprotective effect against NSAID, SEGA (3a) also expedites the healing of already damaged gastric mucosa. Radiolabeled ((99m)Tc-labeled SEGA (3a)) tracer studies confirm that SEGA (3a) enters into mitochondria of gastric mucosal cell in vivo, and it is quite stable in serum. Thus, SEGA (3a) bears an immense potential to be a novel gastroprotective agent against NSAID-induced gastropathy.     

Tristetraprolin Mediates Radiation-Induced TNF-α Production in Lung Macrophages

The efficacy of radiation therapy for lung cancer is limited by radiation-induced lung toxicity (RILT). Although tumor necrosis factor-alpha (TNF-α) signaling plays a critical role in RILT, the molecular regulators of radiation-induced TNF-α production remain unknown. We investigated the role of a major TNF-α regulator, Tristetraprolin (TTP), in radiation-induced TNF-α production by macrophages. For in vitro studies we irradiated (4 Gy) either a mouse lung macrophage cell line, MH-S or macrophages isolated from TTP knockout mice, and studied the effects of radiation on TTP and TNF-α levels. To study the in vivo relevance, mouse lungs were irradiated with a single dose (15 Gy) and assessed at varying times for TTP alterations. Irradiation of MH-S cells caused TTP to undergo an inhibitory phosphorylation at Ser-178 and proteasome-mediated degradation, which resulted in increased TNF-α mRNA stabilization and secretion. Similarly, MH-S cells treated with TTP siRNA or macrophages isolated from ttp (−/−) mice had higher basal levels of TNF-α, which was increased minimally after irradiation. Conversely, cells overexpressing TTP mutants defective in undergoing phosphorylation released significantly lower levels of TNF-α. Inhibition of p38, a known kinase for TTP, by either siRNA or a small molecule inhibitor abrogated radiation-induced TNF-α release by MH-S cells. Lung irradiation induced TTP^Ser178 phosphorylation and protein degradation and a simultaneous increase in TNF-α production in C57BL/6 mice starting 24 h post-radiation. In conclusion, irradiation of lung macrophages causes TTP inactivation via p38-mediated phosphorylation and proteasome-mediated degradation, leading to TNF-α production. These findings suggest that agents capable of blocking TTP phosphorylation or stabilizing TTP after irradiation could decrease RILT.     

Cloning and characterization of a mitochondrial glyoxalase II from Brassica juncea that is upregulated by NaCl, Zn, and ABA

A cDNA (1061 bp) Bj glyII was cloned from a mannitol induced library of Brassica juncea. It encoded a protein of 335 amino acids with a molecular weight of 36.52 kDa. The deduced amino acid sequence of the clone showed 92% and 56% identity with Pennisetum and rice glyoxalase II, respectively, and 30% identity was observed with the human glyoxalase II. Search for the identical residues revealed the presence of highly conserved THHHXDH domain which is involved in zinc binding. p-NN and pSORT analysis of this sequence revealed a N-terminal mitochondrial target peptide. The cDNA was cloned in pMAL and a fusion protein with MBP (78 kDa) was expressed in Escherichia coli. The recombinant protein was purified approximately sixfold by affinity purification on amylose column and showed its pH optima at 7.0. The K(m) was determined to be 120 microM using S-d-lactoylglutathione as substrate. The expression of Bj glyII under various abiotic stress conditions showed that it is upregulated by salinity, heavy metal stress, and ABA.     

Behavioral responses of the whitebacked planthopperSogatella furcifera (Homoptera: Delphacidae) on rice plants whose odors have been masked

In a two-choice test, moreS. furcifera females settled more often on exposed plants than on parafilm-masked ones, regardless of the susceptibility of rice varieties. This indicates that rice volatiles play an important role in the insect's short-range orientation to its host. The fact that more insects settled on exposed resistant Rathu Heenati (RHT) than to masked susceptible Taichung Native 1 (TN1) suggests that there must be certain common volatiles released by both varieties. Few females landed on masked plants of either RHT or TN1. This implies that the insect could not recognize at a distance that a plant was resistant or susceptible without olfactory stimuli.S. furcifera excreted less honeydew on masked plants than on exposed ones for both varieties and more on masked TN1 than on exposed RHT. The electronic monitoring of feeding behavior demonstrates that the insect made more frequent probes and had shorter phloem ingestion durations on exposed RHT than on exposed TN1 and on masked RHT than on masked TN1. Moreover, the insect had longer phloem ingestion durations on masked TN1 than on exposed RHT. These results suggest that volatile chemicals given off by resistant RHT plants have a negative effect on feeding.     

Microbial production of 1,3-propanediol: Recent developments and emerging opportunities

1,3-Propanediol, a valuable bifunctional molecule, can be produced from renewable resources using microorganisms. It has several promising properties for many synthetic reactions, particularly for polymer and cosmetic industries. By virtue of being a natural product, relevant biochemical pathways can be harnessed into fermentation processes to produce 1,3-propanediol. Various strategies for the microbial production of 1,3-propanediol are reviewed and compared in this article with their promises and constraints. Furthermore, genetic and metabolic engineering could significantly improve product yields and overcome the limitations of fermentation technology. Present review gives an overview on 1,3-propanediol production by wild and recombinant strains. It also attempts to encompass the various issues concerned in utilization of crude glycerol for 1,3-propanediol production, with particular emphasis laid on biodiesel industries. This review also summarizes the present state of strategies studied for the downstream processing and purification of biologically produced 1,3-propanediol. The future prospect of 1,3-propanediol and its potential as a major bulk chemical are discussed under the light of the current research.     

A comparative study of pterion formation and its variations in the skulls of Nigerians and Indians

An attempt has been made to study and compare the incidence and variations in the pterion formation in the skulls of 40 Nigerians and 72 Indians obtained from the Department of Anatomy, University of Jos, Nigeria. The present study concludes: 1. All the three varieties of pterion i.e. sphenoparietal, frontotemporal and stellate are found in both races. 2. The frequency of sphenoparietal pterion is high in both races (Indians 95.3%, Nigerians 84.79%) while the frontotemporal (Indians 3.46%, Nigerians 10.11%) and the stellate (Indians 1.38%, Nigerians 5.06%) pterion are more common in Nigerians. 3. The frequency of epipteric bone is high in Indians (Indians 11.79%, Nigerians 3.79%) and is more commonly associated with sphenoparietal pterion. 4. No epipteric bone is associated with stellate pterion in both races. 5. The difference in the distance of pterion from the zygomatic arch is highly significant between two races on both sides. 6. The difference in the distance of pterion from the frontozygomatic suture is insignificant between the two races. 7. The frequency of "high Pterion" is more in Nigerians on both sides. 8. The frequency of "Backward Pterion" is more in Indians on the right side, whereas little more in Nigerians on the left side.     

Synthetic and novel biocatalytic resolution studies on (+/-)-5/6/7-acetoxy-4-aryl-3,4-dihydrocoumarins

Eleven (+/-)-5/6/7-acetoxy-4-aryl-3,4-dihydrocoumarins have been synthesised in two steps starting from the coupling of cinnamic acid/substituted cinnamic acid with appropriate phenols, followed by acetylation in 50-83% overall yields. All hydroxy- and acetoxycoumarins were unambiguously identified on the basis of their spectral data. Candida antarctica lipase-catalysed deacetylation of these racemic acetoxydihydrocoumarins in dioxane occurred with moderate enantioselectivity. This is one of the rare examples of resolution using phenolic ester moiety as a remote handle for chiral recognition by a lipase.