Suitability of soil microbial parameters as indicators of heavy metal pollution

Several microbial parameters (microbial biomass, respiration, dehydrogenase, phosphatase, sulphatase, glucosidase, protease and urease activities) were measured in soils from five sites located in urban green areas close to roads differing in traffic density. Our aims were to evaluate the suitability of such parameters as field biomarkers of stress induced by heavy metal pollution, and to compare results obtained by single microbial parameters with results given by an index expressing the average microbial (AME) response of the microbial community. Data showed that all parameters were significantly reduced in the sites characterized by the highest load of metals in soil. Dehydrogenase, sulphatase, glucosidase activities and respiration, declined exponentially with increasing metal concentration, whereas phosphatase activity and AME decreased following a sigmoidal type relationship. In contrast, protease, urease and microbial biomass were not significantly correlated with soil metal concentration. Microbial parameters differed both in sensitivity to critical metal concentrations and in the rate of decline at increasing metal loads in soil. Due to the complex interplay of chemical, physical and biological factors which influence microbial activities and biomass, the proposed index (AME) appeared more suitable than single microbial parameters for a biomonitoring study of this type.     

Phosphorylation networks regulating JNK activity in diverse genetic backgrounds

Cellular signaling networks have evolved to enable swift and accurate responses, even in the face of genetic or environmental perturbation. Thus, genetic screens may not identify all the genes that regulate different biological processes. Moreover, although classical screening approaches have succeeded in providing parts lists of the essential components of signaling networks, they typically do not provide much insight into the hierarchical and functional relations that exist among these components. We describe a high-throughput screen in which we used RNA interference to systematically inhibit two genes simultaneously in 17,724 combinations to identify regulators of Drosophila JUN NH(2)-terminal kinase (JNK). Using both genetic and phosphoproteomics data, we then implemented an integrative network algorithm to construct a JNK phosphorylation network, which provides structural and mechanistic insights into the systems architecture of JNK signaling.     

Depolarization and muscarinic excitation induced in a sympathetic ganglion by vasoactive intestinal polypeptide

The effects of vasoactive intestinal polypeptide (VIP) in the superior cervical ganglion of the cat were studied in vitro and in vivo with sucrose gap and multiunit recording, respectively. At a dose of 0.03 to 0.12 nanomole, VIP produced a dose-dependent, prolonged (3 to 15 minutes) depolarization of the ganglion and enhanced the ganglionic depolarization elicited by the muscarinic agonist acetyl-beta-methylcholine. At a dose of 1.8 to 10 nanomoles, the peptide enhanced and prolonged the postganglionic discharge elicited by acetyl-beta-methylcholine, enhanced muscarinic transmission in ganglia treated with an anticholinesterase agent, and enhanced the late muscarinic discharge elicited by acetylcholine. VIP did not affect the early nicotinic discharge elicited by acetylcholine or by electrical stimulation of the preganglionic nerve. It is concluded that VIP has a selective facilitatory action on muscarinic excitatory mechanisms in the superior cervical ganglion of the cat.     

Lipids and fatty acids in wild and pond-reared mud crab Scylla serrata (Forsskål) during ovarian maturation and spawning

Wild‐caught and pond‐reared female mud crab Scylla serrata at different stages of ovarian maturation were collected from Samar and Capiz, Philippines. Crabs were categorized into five stages according to the external morphological and microscopic appearance of the most advanced oocytes. The ovaries, hepatopancreas, muscle and newly spawned eggs (NSE) were analysed for lipid class components and fatty acids. Total lipid was higher in pond‐reared than in wild‐caught crabs but increased with ovarian maturation in both groups. Ovarian lipid peaked at the fully mature stage, coinciding with a decline in hepatopancreatic and muscle lipids. Lipid levels declined significantly in spent females. The tissues contained elevated highly unsaturated fatty acids such as arachidonic (20:4n‐6), eicosapentaenoic (20:5n‐3) and docosahexaenoic (22:6n‐3) acids, but at higher levels in late maturing and fully mature ovaries and in NSE. The type of lipid class and fatty acid components in mature ovaries as well as in NSE are generally considered to be indicative of their importance in reproductive physiology and embryonic and larval development.     

Expression of ROR1 in patients with renal cancer--a potential diagnostic marker

Background: The ectopic expression of receptor tyrosine kinase Ror1 has been reported in patients with hematological malignancies such as chronic lymphocytic leukemia and acute lymphoblastic leukemia. Here we report, for the first time, expression of ROR1 gene in both tumor tissues and peripheral blood mononuclear cells (PBMC) from patients with renal cancer (RC). Methods: In the current study, the expression of ROR1 gene was semi-quantitatively measured in PBMC and tumor tissues from 16 RC patients as well as PBMC from 22 healthy individuals relative to the expression of the housekeeping gene phosphoglucomutase 1 by RT-PCR. Results: Our results showed that ROR1 was expressed at gene level in 81.3% of renal tumor tissues (13 out of 16) whereas it was expressed in 94% of PBMC from RC patients (15 out of 16). A weak expression of ROR1 was observed in PBMC of 4 out of 22 healthy individual. A significant expression of ROR1 was observed in PBMC from RC patients when compared to that in PBMC from normal healthy individuals (P<0.001). The expression of ROR1 in PBMC may reflect a shedding of tumor cells into blood stream. Conclusion: We conclude that detection of a high level of ROR1 expression in blood cells might assist in early detection of renal malignancies, providing taking into consideration the clinical symptoms of the disease. Key Words: ROR1, Ectopic expression, Renal cancer     

Book reviews

Marilyn Holly is an Associate Professor of Philosophy at the University of Florida. Her special interests include political philosophy, ethics and ecology, Jungian thought, and Native American spirituality in its relation to the environment. She is currently at work on a monograph-length piece on the latter topic. She has taught an undergraduate course in ethics and ecology, and plans to do so again. The following essay emerged from her search for a suitable text for such a course.     

Immune response of BALB/c mouse immunized with recombinant MSPs proteins of Anaplasma marginale binding to immunostimulant complex (ISCOM)

Anaplasmosis, caused by Anaplasma marginale, results in significant economic losses of cattle in tropical and subtropical regions worldwide. Six major surface proteins (MSPs) were well characterized and designated as MSP1, MSP2, MSP3, MSP4, and MSP5. The objective of this study was to evaluate the humoral immune response of BALB/c mice against the recombinant MSPs, incorporated into immunostimulating complex (ISCOM). The recombinant proteins purified by Ni-NTA columns were incorporated into ISCOM and ISCOMATRIX by the lipid film hydration method. BALB/c mice immunized with ISCOM/rMSPs and ISCOMATRIX/rMSPs vaccines produced whole IgG, IgG1, and IgG2a, in contrast to the negative groups (PBS and ISCOMATRIX adjuvant). All groups that received antigen responded specifically against the rMSPs by Western blotting, showing the rMSP1a (60-105kDa), rMSP1b (100kDa), rMSP4 (47kDa), and rMSP5 (29kDa). Additional studies will have to be performed in cattle to evaluate the humoral and cellular mechanisms of this subunit vaccine and their possible use as protective vaccines against homologous and heterologous strains of A. marginale.