Effect of Withania somnifera on glycosaminoglycan synthesis in carrageenin-induced air pouch granuloma

The effect of W. somnifera on glycosaminoglycan synthesis in the granulation tissue of carrageenin-induced air pouch granuloma was studied. W. somnifera was shown to exert significant inhibitory effect on incorporation of 35S into the granulation tissue. The uncoupling effect on oxidative phosphorylation (ADP/O ratio reduction) was also observed in the mitochondria of granulation tissue. Further, Mg2+ dependent ATPase activity was found to be influenced by W. somnifera. W. somnifera also reduced the succinate dehydrogenase enzyme activity in the mitochondria of granulation tissue.     

High levels of cytosolic free calcium inhibit dephosphorylation of insulin receptor and glycogen synthase.

Treatment of adipocytes with depolarizing concentrations of K+ (40 mM) for 60 min increased [Ca2+]i from 158 +/- 28 nM to 328 +/- 38 nM. This significantly reduced (up to 80% inhibition) dephosphorylation of insulin receptor (IR), EGF receptor (EGF-R) and glycogen synthase (GS). The calcium channel blocker, nitrendipine (30 microM), or Ca2+ free medium completely prevented K(+)-induced inhibition of phosphoprotein phosphatase (PPTase). This effect of high [Ca2+]i was completely reversible when the cells were returned into the non-depolarizing medium. Trypsin treatment (4 micrograms/ml) of the membrane fraction containing inhibited PPTase activity, restored dephosphorylation activity to normal suggesting that elevated [Ca2+]i may inhibit PPTase by promoting its association with the inhibitors. These observations indicate that dephosphorylation of IR and GS can be regulated by [Ca2+]i.     

Effect of dieldrin on catalytic potential of field mouse Mus booduga brain acetylcholinesterase

Substrate kinetics of acetylcholinesterase (AChE) were investigated in control and dieldrin-treated Mus booduga brains. Non competitive inhibition with respect to activation by acetylcholine was indicated by decreased maximal velocity (V) without change in Michaelis-Menten constant (Km). Activation energies (delta E) were found to be increased suggesting decreased efficiency of enzyme in dieldrin-treated mouse brains. Fall in the activity potential of AChE may account for the interference of dieldrin or its metabolites with the acetylcholine (ACh)--AChE system and deserve consideration in contributing to the neurotoxicity.     

Development of Australian commercial producers of invertebrate biological control agents from 1971 to 2014

The Australian industry producing invertebrate biological control agents (BCAs) commercially was described for the first time through interviews with company owners, citrus pest management researchers and citrus growers. This industry started with citrus pest management in 1971. Over 40 years it expanded from one company and one commercial BCA to peak at nine companies operating from 2002 to 2010. A period of consolidation resulted in five companies producing 36 commercial BCAs in 2014. Annual gross sales were <AU$10 million compared to >AU$400 million spent on insecticides. Barriers to industry growth included high costs of developing new commercial BCAs partly due to regulatory costs associated with importation of new BCAs into Australia, and low adoption of commercial BCAs due to limited access to information and training. The industry responded to these barriers by collaborating with stakeholders to develop new commercial BCAs, and developing an accreditation scheme to build technical capacity and encourage adoption.