Phenotypic modulation of chronic lymphocytic leukemia cells by phorbol ester: induction of IgM secretion and changes in the expression of B cell-associated surface antigens

Freshly explanted neoplastic populations from 22 cases of phenotypically well-characterized chronic type B lymphocytic leukemia were studied for their capacity to respond to the phorbol ester TPA in vitro. In all but four cases the secretion of IgM was either induced or increased, often to a high level. In contrast, the export of free immunoglobulin (Ig) light chains, an almost consistent feature of the B lymphocytic leukemias, remained relatively constant after TPA treatment. Parallel changes in leukemic cell surface phenotype were probed with both "conventional" and monoclonal antibodies, revealing some modulation of markers in every case investigated. A diminution in the level of surface Ig (preferentially IgD) and the accumulation of cytoplasmic Ig observed after phorbol ester treatment were accompanied by a corresponding reduction or loss of the B1 antigen and usually of B2 when present. The most consistent change induced by TPA was the appearance of BB-1, a marker of activated B lymphocytes, which was rarely expressed on fresh leukemic cells. Another marker of activated lymphocytes, LB-1, was also often induced or increased in its expression after exposure of the cells to TPA. The magnitude of the TPA response appeared to relate to the stage of maturation arrest of the individual leukemic clones rather than to any clinical parameter explored. The significance of the findings to normal B cell differentiation and their potential clinical utility are discussed.     

CaСl2 Salt Signaling in Primary Root Architecture and Lateral Root Emergence in Arabidopsis thaliana

Russian Journal of Plant Physiology - Plant root architecture modulates during developmental stages and adjusts with the environmental condition. The cytosolic calcium which is a ubiquitous...     

Slow Regulated Release of H2S Inhibits Oxidative Stress Induced Cell Death by Influencing Certain Key Signaling Molecules

Hydrogen sulphide (H₂S) is one of three gaseous signaling molecules after nitric oxide and carbon monoxide. Various H₂S donor compounds have been synthesized to study its physiological function. Among these compounds sodium hydrosulphide (NaHS), a donor of releasing H₂S rapidly have shown to be protective in certain neuronal cell line but several in vivo studies have generated conflicting data. Furthermore several slow releasing H₂S donors have been shown to have positive effects on cells in culture. The intracellular concentration of H₂S and hence its rate of production may be a factor in keeping the balance between its neuroprotective and toxic effects. The present study was undertaken to deduce how a rapid releasing H₂S donor (NaHS) as opposed to a slow releasing donor (ADTOH), affect oxidative stress related intracellular components and survival of RGC-5 cells. It was concluded that when RGC-5 cells are exposed to the toxic effects of glutamate in combination with buthionine sulfoxime (Glu/BSO), ADTOH was more efficacious in inhibiting apoptosis, scavenging reactive oxygen species (ROS), stimulation of glutathione (GSH) and gluthathione-S-transferase (GST). Western blot and qPCR analysis showed ADTOH increased the levels of Nrf2, HO-1, PKCα, p-Akt, Bcl-2 and XIAP but caused a decrease of Nfκβ and xCT greater than NaHS. This study is first to compare the efficacy of two H₂S donor drugs as potential neuroprotectants and demonstrate that slow regulated release of H₂S to cell culture can be more beneficial in inhibiting oxidative stress induced cell death.     

Suitability of tomato leaves for larval development of Potato Tuber Moth,Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae)

The potato tuber moth (PTM) is an important pest of the potato plant and its tuber. With the expansion of its geographic range, the PTM could be potential threat to the tomato (Solanum lycopersicum L.), a congeneric species of the potato. To assess that risk, we tested larval feeding and development of PTM on leaves of five cultivated tomato varieties namely Moneymaker, Campari, Ailsa Craig, LA3475, E6203 and one wild tomato variety S. pimpinellifolium. PTM larvae accepted all tested plant leaves and developed into adults. Larval development was fastest on the Ailsa Craig variety. Pupae developed fastest on the Moneymaker variety and slowest on LA3475. Host acceptance and survival were highest on Ailsa Craig and lowest on LA3475. The significantly highest male proportion occurred on LA3475 variety. The study showed that PTM could be a potential threat to tomato cultivation which is rapidly increasing in temperate regions owing to climate change.