PhosR enables processing and functional analysis of phosphoproteomic data

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Functional Genomics In Vivo Reveal Metabolic Dependencies of Pancreatic Cancer Cells

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Estimating the Population Mean Using Extreme Ranked Set Sampling

Precision of the estimate of the population mean using ranked set sample (RSS) relative to using simple random sample (SRS), with the same number of quantified units, depends upon the population and success in ranking. In practice, even ranking a sample of moderate size and observing the ith ranked unit (other than the extremes) is a difficult task. Therefore, in this paper we introduce a variety of extreme ranked set sample (ERSSs) to estimate the population mean. ERSSs is more practical than the ordinary ranked set sampling, since in case of even sample size we need to identify successfully only the first and/or the last ordered unit or in case of odd sample size the median unit. We show that ERSSs gives an unbiased estimate of the population mean in case of symmetric populations and it is more efficient than SRS, using the same number of quantified units. Example using real data is given. Also, parametric examples are given.     

Carbohydrate and organic acid composition of effective and ineffective root nodules of Phaseolus vulgaris

Dicarboxylic acid transport mutants of Rhizobium species are usually deficient in their ability to fix atmospheric dinitrogen. We report here a study comparing the physiology of root nodules on Phaseolus vulgaris L. cv. Goldie induced by an effective strain of Rhizobium leguminosarum biovar phaseoli and a C₄-dicarboxylic acid utilization mutant. The mutant, while able to form nodules, was ineffective in N₂ fixation. Carbohydrates and organic acids of roots and nodules formed by the 2 strains were monitored at 3-day intervals from 13 to 34 days after inoculation. Both carbohydrates and organic acids accumulated in ineffective nodules in comparison with the effective nodules. The concentration of malic acid was tenfold higher in ineffective nodules than in effective nodules. Other organic acids, i.e., lactate, malonate, ascorbate and gluconate, were also detected. Lactate and ascorbate were the only other organic acids accumulating in ineffective nodules. The most prevalent carbohydrates found in both types of nodules were sucrose, glucose and fructose. Myo-inositol was the only cyclitol detected in both types of nodules. Carbohydrates and organic acids were present in lower concentration in roots than in nodules, except for lactate. These compounds were not consistently detected in higher concentration in roots from plants inoculated with the mutant strain, as was the case in nodules.     

Adherence ofStaphylococcus epidermidis to human pharyngeal epithelial cells: Evidence for lipase-sensitive adhesin and glycoprotein receptor

The adherence of eight strains ofStaphylococcus epidermidis to human pharyngeal epithelial cells (PEC) was investigated. All bacterial strains were nonencapsulated and non-slime producers. Binding was mannose resistant and was not related to surface hydrophobicity and surface charge of bacteria. Adherence to epithelial cells was reduced four- to tenfold (P<0.01) on pretreatment of bacteria with lipase while neuraminidase, phospholipase C, trypsin, and sodium periodate did not alter their binding. The surface carbohydrate profile of bacteria was studied by monitoring adherence to Lectin-Sepharoses. The bacteria did not conform to any pattern, and there was no relation to strain variation. The pretreatment of PEC with trypsin and sodium metaperiodate produced a marked reduction in bacterial binding (three- to 25-fold, P<0.01), but neuraminidase, phospholipase C, and lipase did not have any such effect. These findings provide evidence that the receptors on the surface of PEC are glycoprotein in nature, while the bacterial adhesin is a lipase-sensitive material.     

Lithostratigraphy of the Triassic in Jordan

The Triassic sequence of Jordan east of the Rift-valley consists of an over 1000 m thick sequence of sedimentary rocks. These sediments were deposited near the shore, either under terrestrial conditions within the intertidal range just offshore, or under saline conditions in a sabkha lagoonal environment. Nine formations are described: Um Irna (80 m), Ma'in (40 m), Dardun (60 m), Ain Musa (80 m), Hisban (35 m), Mukheiris (90 m), Iraq al Amir (170 m), Um Tina (260 m), Abu Ruweis (200 m). With the exception of large parts of the Um Tina and the Abu Ruweis Formations all other formations are exposed along the NE coast of the Dead Sea and the deep wadis just E and NE of it. Each formation is defined by a type section. The sedimentary rocks are intruded by dykes and sills composed of diabase and gabbro of uniform composition and older than Upper Jurassic in age. Comparison of Triassic rocks from the west side of the Rift (DRUCKMAN 1974, 1977) indicates that the facies and thickness of Jordanian Triassic rocks as well as the northernmost limit of intrusive rocks can only be fitted with those of the central Negev. A relative movement of the Abrabian block against Palestine-Sinai of at least 100 km along the Rift is probable (BANDEL 1981).     

The effect of orally administered viable probiotic and dairy lactobacilli on mouse lymphocyte proliferation

Four common Lactobacillus strains were screened for their effects on proliferation of mouse splenic lymphocytes. Mice received perorally 10(9) viable bacteria kg(-1) body weight for 7 days. Lactobacillus acidophilus treatment enhanced ex vivo basal proliferation (by 43%) and B-cell response at suboptimal and optimal concentrations of lipopolysaccharide (LPS) (by 27-28%). Conversely, Lactobacillus casei, Lactobacillus gasseri and Lactobacillus rhamnosus inhibited both basal proliferation (by 14-51%) and mitogen-stimulated lymphoproliferation, particularly at supra-optimal concentrations of concanavalin A (by 43-68%) and LPS (by 23-62%). Therefore, these Lactobacillus strains demonstrate strain-specific effects on B- and T-cells and may also alter the splenocyte sensitivity to the cytotoxic effects of mitogens.     

Role of calcineurin biosignaling in cell secretion and the possible regulatory mechanisms

Cyclic adenosine monophosphate (cAMP) and calcium ions (Ca²⁺) are two chemical molecules that play a central role in the stimulus-dependent secretion processes within cells. Ca²⁺ acts as the basal signaling molecule responsible to initiate cell secretion. cAMP primarily acts as an intracellular second messenger in a myriad of cellular processes by activating cAMP-dependent protein kinases through association with such kinases in order to mediate post-translational phosphorylation of those protein targets. Put succinctly, both Ca²⁺ and cAMP act by associating or activating other proteins to ensure successful secretion. Calcineurin is one such protein regulated by Ca²⁺; its action depends on the intracellular levels of Ca²⁺. Being a phosphatase, calcineurin dephosphorylate and other proteins, as is the case with most other phosphatases, such as protein phosphatase 2A (PP2A), PP2C, and protein phosphatase-1 (PP1), will likely be activated by phosphorylation. Via this process, calcineurin is able to affect different intracellular signaling with clinical importance, some of which has been the basis for development of different calcineurin inhibitors. In this review, the cAMP-dependent calcineurin bio-signaling, protein-protein interactions and their physiological implications as well as regulatory signaling within the context of cellular secretion are explored.