Treatment of viral and neoplastic diseases with double-stranded RNA derivatives and other new agents

Many attempts have been made to inhibit viral and neoplastic diseases by targeting the RNA system. The pathophysiologic significance of the microRNA system and the therapeutic potential of its manipulation are discussed. Studies of double-stranded RNA derivatives are reviewed. The therapeutic potential of one of these compounds, polyI:MPC, is emphasized. Studies of other related antiviral and antineoplastic agents are discussed, including 2'-deoxyoligocytidilates and telomerase inhibitors.     

Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry analysis of oligosaccharides and oligosaccharide alditols obtained by hydrolysis of agaroses and carrageenans, two important types of red seaweed polysaccharides

MALDI-TOF mass spectrometry analyses of several oligosaccharides (aldoses) and oligosaccharide alditols derived from agaroses, kappa- and iota-carrageenans using different matrices (2,5-dihydroxybenzoic acid, nor-harmane, ferulic acid, and the ionic liquid matrices 2,5-dihydroxybenzoic acid-n-butylamine and ferulic acid-n-butylamine) were conducted. These carbohydrates were selected as model compounds to study the MALDI prompt and post-source decay (PSD) fragmentation processes of both families of oligosaccharides. Sulfated alditols showed in the negative-ion mode the molecular ion as [M−Na]⁻ together with the species yielded by their prompt fragmentation (mainly desulfation) while the sulfated oligosaccharides (aldoses) showed mainly glycosidic prompt fragmentation (glycosidic C-cleavages and desulfation). Non-sulfated aldoses and alditols, which could only be analyzed in positive-ion mode ([M+Na]⁺), did not suffer any prompt fragmentation. The former yielded cross-ring fragmentation in the PSD mode. Best results were obtained by using 2,5-dihydroxybenzoic acid and/or nor-harmane as matrices for all the compounds studied.     

The thioredoxin gene family in rice: genome-wide identification and expression profiling under different biotic and abiotic treatments

Thioredoxin (TRX) is a multi-functional redox protein. Genome-wide survey and expression profiles of different stresses were observed. Conserved amino acid residues and phylogeny construction using the OsTRX conserved domain sequence suggest that the TRX gene family can be classified broadly into six subfamilies in rice. We compared potential gene birth-and-death events in the OsTRX genes. The Ka/Ks ratio is a measure to explore the mechanism and 3 evolutionary stages of the OsTRX genes divergence after duplication. We used 270 TRX genes from monocots and eudicots for synteny analysis. Furthermore, we investigated expression profiles of this gene family under 5 biotic and 3 abiotic stresses. Several genes were differentially expressed with high levels of expression and exhibited subfunctionalization and neofunctionalization after the duplication event response to different stresses, which provides novel reference for the cloning of the most promising candidate genes from OsTRX gene family for further functional analysis.     

Site-specific conjugation of a lanthanide chelator and its effects on the chemical synthesis and receptor binding affinity of human relaxin-2 hormone

Diethylenetriamine pentaacetic acid (DTPA) is a popular chelator agent for enabling the labeling of peptides for their use in structure-activity relationship study and biodistribution analysis. Solid phase peptide synthesis was employed to couple this commercially available chelator at the N-terminus of either the A-chain or B-chain of H2 relaxin. The coupling of the DTPA chelator at the N-terminus of the B-chain and subsequent loading of a lanthanide (europium) ion into the chelator led to a labeled peptide (Eu-DTPA-(B)-H2) in low yield and having very poor water solubility. On the other hand, coupling of the DTPA and loading of Eu at the N-terminus of the A-chain led to a water-soluble peptide (Eu-DTPA-(A)-H2) with a significantly improved final yield. The conjugation of the DTPA chelator at the N-terminus of the A-chain did not have any impact on the secondary structure of the peptide determined by circular dichroism spectroscopy (CD). On the other hand, it was not possible to determine the secondary structure of Eu-DTPA-(B)-H2 because of its insolubility in phosphate buffer. The B-chain labeled peptide Eu-DTPA-(B)-H2 required solubilization in DMSO prior to carrying out binding assays, and showed lower affinity for binding to H2 relaxin receptor, RXFP1, compared to the water-soluble A-chain labeled peptide Eu-DTPA-(A)-H2. The mono-Eu-DTPA labeled A-chain peptide, Eu-DTPA-(A)-H2, thus can be used as a valuable probe to study ligand-receptor interactions of therapeutically important H2 relaxin analogs. Our results show that it is critical to choose an approriate site for incorporating chelators such as DTPA. Otherwise, the bulky size of the chelator, depending on the site of incorporation, can affect yield, solubility, structure and pharmacological profile of the peptide.     

Activation of the pyrin inflammasome by intracellular Burkholderia cenocepacia

Burkholderia cenocepacia is an opportunistic pathogen that causes chronic infection and induces progressive respiratory inflammation in cystic fibrosis patients. Recognition of bacteria by mononuclear cells generally results in the activation of caspase-1 and processing of IL-1β, a major proinflammatory cytokine. In this study, we report that human pyrin is required to detect intracellular B. cenocepacia leading to IL-1β processing and release. This inflammatory response involves the host adapter molecule ASC and the bacterial type VI secretion system (T6SS). Human monocytes and THP-1 cells stably expressing either small interfering RNA against pyrin or YFP-pyrin and ASC (YFP-ASC) were infected with B. cenocepacia and analyzed for inflammasome activation. B. cenocepacia efficiently activates the inflammasome and IL-1β release in monocytes and THP-1. Suppression of pyrin levels in monocytes and THP-1 cells reduced caspase-1 activation and IL-1β release in response to B. cenocepacia challenge. In contrast, overexpression of pyrin or ASC induced a robust IL-1β response to B. cenocepacia, which correlated with enhanced host cell death. Inflammasome activation was significantly reduced in cells infected with T6SS-defective mutants of B. cenocepacia, suggesting that the inflammatory reaction is likely induced by an as yet uncharacterized effector(s) of the T6SS. Together, we show for the first time, to our knowledge, that in human mononuclear cells infected with B. cenocepacia, pyrin associates with caspase-1 and ASC forming an inflammasome that upregulates mononuclear cell IL-1β processing and release.     

Human relaxin-2: historical perspectives and role in cancer biology

One of the most recognised and studied family of peptide hormones is the insulin superfamily. Within this family is the relaxin subfamily which comprises seven members: relaxin-1, -2 and -3 and insulin-like peptides 3, 4, 5 and 6. Besides exhibiting sequence similarities, each member exists as an active A-B heterodimer linked by three disulfide bonds. This mini-review is divided into three broad themes: an overview of all insulin superfamily members (including structural similarities); roles of each superfamily member and finally, a focus on the pleiotropic peptide hormone, human relaxin-2. In addition to promoting vasodilatory effects leading to evaluation in Phase III clinical trials for the treatment of acute heart failure, relaxin has recently been shown to be highly expressed by cancer cells, aiding in their proliferation, invasiveness and metastasis. These contrary effects of relaxin are discussed together with current efforts in the development of relaxin antagonists that may possess future therapeutic potential for the treatment of certain cancers.     

A new species of the cicada genus Cicadatra Kolenati, 1857 (Hemiptera, Cicadidae) from Pakistan with a key to the known species of Pakistani Cicadatra

A new species of cicada, Cicadatra ziaraticasp. n., is described from Pakistan. Male genitalia, timbal and opercula are described and illustrated as important diagnostic characters. Biological notes are also provided. A key to the known Cicadatra of Pakistan is provided.     

YIPF5 and YIF1A recycle between the ER and the Golgi apparatus and are involved in the maintenance of the Golgi structure

Yip1p/Yif1p family proteins are five-span transmembrane proteins localized in the Golgi apparatus and the ER. There are nine family members in humans, and YIPF5 and YIF1A are the human orthologs of budding yeast Yip1p and Yif1p, respectively. We raised antisera against YIPF5 and YIF1A and examined the localization of endogenous proteins in HeLa cells. Immunofluorescence, immunoelectron microscopy and subcellular fractionation analysis suggested that YIPF5 and YIF1A are not restricted to ER exit sites but also localized in the ER-Golgi intermediate compartment (ERGIC) and some in the cis-Golgi at steady state. Along with ERGIC53, YIPF5 and YIF1A remained in the cytoplasmic punctate structures after brefeldin A treatment, accumulated in the ERGIC and the cis-Golgi after treatment with AlF₄^- and accumulated in the ER when ER to Golgi transport was inhibited by Sar1(H79G). These results supported the localization of YIPF5 and YIF1A in the ERGIC and the cis-Golgi, and strongly suggested that they are recycling between the ER and the Golgi apparatus. Analysis by blue native PAGE and co-immunoprecipitation showed that YIPF5 and YIF1A form stable complexes of three different sizes. Interestingly, the knockdown of YIPF5 or YIF1A caused partial disassembly of the Golgi apparatus suggesting that YIPF5 and YIF1A are involved in the maintenance of the Golgi structure.