A P Element Containing Suppressor of Hairy-Wing Binding Regions Has Novel Properties for Mutagenesis in Drosophila Melanogaster

P elements are widely used as insertional mutagens to tag genes, facilitating molecular cloning and analyses. We modified a P element so that it carried two copies of the suppressor of Hairy-wing [su(Hw)] binding regions isolated from the gypsy transposable element. This transposon was mobilized, and the genetic consequences of its insertion were analyzed. Gene expression can be altered by the su(Hw) protein as a result of blocking the interaction between enhancer/silencer elements and their promoter. These effects can occur over long distances and are general. Therefore, a composite transposon (SUPor-P for suppressor-P element) combines the mutagenic efficacy of the gypsy element with the controllable transposition of P elements. We show that, compared to standard P elements, this composite transposon causes an expanded repertoire of mutations and produces alleles that are suppressed by su(Hw) mutations. The large number of heterochromatic insertions obtained is unusual compared to other insertional mutagenesis procedures, indicating that the SUPor-P transposon may be useful for studying the structural and functional properties of heterochromatin.     

Fair Scheduling for Input Buffered Switches

Input buffered switch architecture has become attractive for implementing high performance switches for workstation clusters. It is challenging to provide a scheduling technique that is both highly efficient and fair in resource allocation. In this paper, we first introduce an iterative Fair Scheduling (iFS) scheme for input buffered switches that supports fair bandwidth distribution among the flows and achieves asymptotically 100% throughput. We then apply the idea of fair scheduling to switches with multicasting capability and propose an mFS scheme which allocates bandwidth to various flows according to their reservations. We show that mFS produces throughput comparable to the existing schemes while distributing the bandwidth as per the given reservations. Extensive simulation results are presented to validate the effectiveness of our proposed schemes.     

Peptide hydrolases in senescing ragi leaves

Two peptide hydrolases — one active at pH 7.0 and the other at pH 3.4 (SH-dependent) were detected in ragi (Eleusine coracana Gaertn. cv. PR 202) leaves. The absolute activities of both acid and neutral peptide hydrolases were move or less stable in attached leaves and exhibited a mild rise in excised leaves, whereas the specific activities exhibited a significant rise. Light and growth regulators were ineffective in changing the course of absolute activity whereas cytokinins stimulated specific activities of both acid and neutral peptide hydrolases. Though the rates were different, protein decline was positively correlated with the changes in activities of peptide hydrolases. Cycloheximide retarded chlorophyll and protein decline and also prevented the rise in peptide hydrolases. Peptide hydrolases thus do not have an active role in senescence.     

Ceranib‐2‐induced suicidal erythrocyte death

Ceramide is known to trigger apoptosis of nucleated cells and eryptosis of erythrocytes. Eryptosis is characterized by cell shrinkage and cell membrane scrambling with phosphatidylserine translocation to the erythrocyte surface. Besides ceramide, stimulators of eryptosis include increase of cytosolic Ca²⁺‐activity ([Ca²⁺]_i) and oxidative stress. Ceramide is degraded by acid ceramidase and inhibition of the enzyme similarly triggers apoptosis. The present study explored, whether ceramidase inhibitor Ceranib‐2 induces eryptosis. Flow cytometry was employed to quantify phosphatidylserine‐exposure at the cell surface from annexin‐V‐binding, cell volume from forward scatter, [Ca²⁺]_i from Fluo3‐fluorescence, reactive oxygen species (ROS) from DCF dependent fluorescence, and ceramide abundance utilizing specific antibodies. Hemolysis was estimated from hemoglobin concentration in the supernatant. A 48 h exposure of human erythrocytes to Ceranib‐2 significantly increased the percentage of annexin‐V‐binding cells (≥50 μM) and the percentage of hemolytic cells (≥10 μM) without significantly modifying forward scatter. Ceranib‐2 significantly increased Fluo3‐fluorescence, DCF fluorescence and ceramide abundance. The effect of Ceranib‐2 on annexin‐V‐binding was not significantly blunted by removal of extracellular Ca²⁺. Ceranib‐2 triggers phospholipid scrambling of the erythrocyte cell membrane, an effect at least in part due to increase of ceramide abundance and induction of oxidative stress, but not dependent on Ca²⁺ entry. Copyright © 2016 John Wiley & Sons, Ltd.     

CD98 Heavy Chain Is a Potent Positive Regulator of CD4+ T Cell Proliferation and Interferon-γ Production In Vivo

Upon their recognition of antigens presented by the MHC, T cell proliferation is vital for clonal expansion and the acquisition of effector functions, which are essential for mounting adaptive immune responses. The CD98 heavy chain (CD98hc, Slc3a2) plays a crucial role in the proliferation of both CD4⁺ and CD8⁺ T cells, although it is unclear if CD98hc directly regulates the T cell effector functions that are not linked with T cell proliferation in vivo. Here, we demonstrate that CD98hc is required for both CD4⁺ T cell proliferation and Th1 functional differentiation. T cell-specific deletion of CD98hc did not affect T cell development in the thymus. CD98hc-deficient CD4⁺ T cells proliferated in vivo more slowly as compared with control T cells. C57BL/6 mice lacking CD98hc in their CD4⁺ T cells could not control Leishmania major infections due to lowered IFN-γ production, even with massive CD4⁺ T cell proliferation. CD98hc-deficient CD4⁺ T cells exhibited lower IFN-γ production compared with wild-type T cells, even when comparing IFN-γ expression in cells that underwent the same number of cell divisions. Therefore, these data indicate that CD98hc is required for CD4⁺ T cell expansion and functional Th1 differentiation in vivo, and suggest that CD98hc might be a good target for treating Th1-mediated immune disorders.     

Botanical,Phytochemical, and Anticancer Properties of the Eucalyptus Species

The genus Eucalyptus (Myrtaceae) is mainly native to Australia; however, some species are now distributed globally. Eucalyptus has been used in indigenous Australian medicines for the treatment of a range of aliments including colds, flu, fever, muscular aches, sores, internal pains, and inflammation. Eucalyptus oils containing volatile compounds have been widely used in the pharmaceutical and cosmetics industries for a multitude of purposes. In addition, Eucalyptus extracts containing nonvolatile compounds are also an important source of key bioactive compounds, and several studies have linked Eucalyptus extracts with anticancer properties. With the increasing research interest in Eucalyptus and its health properties, this review briefly outlines the botanical features of Eucalyptus, discusses its traditional use as medicine, and comprehensively reviews its phytochemical and anticancer properties and, finally, proposes trends for future studies.