bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis and applications of magnetic nanoparticles for biorecognition and point of care medical diagnostics
Authors: Sandhu Adarsh , Handa Hiroshi , Abe Masanori
Published: October 2010

Functionalized magnetic nanoparticles are important components in biorecognition and medical diagnostics. Here, we present a review of our contribution to this interdisciplinary research field. We start by describing a simple one-step process for the synthesis of highly uniform ferrite nanoparticles (d= 20–200 nm) and their functionalization with amino acids via carboxyl groups.

For real-world applications, we used admicellar polymerization to produce 200 nm diameter ‘FG beads’, consisting of several 40 nm diameter ferrite nanoparticles encapsulated in a co-polymer of styrene and glycidyl methacrylate for high throughput molecular screening. The highly dispersive FG beads were functionalized with an ethylene glycol diglycidyl ether spacer and used for affinity purification of methotrexate—an anti-cancer agent. We synthesized sub-100 nm diameter magnetic nanocapsules by exploiting the self-assembly of viral capsid protein pentamers, where single 8, 20, and 27 nm nanoparticles were encapsulated with VP1 pentamers for applications including MRI contrast agents. The FG beads are now commercially available for use in fully automated bio-screening systems.

We also incorporated europium complexes inside a polymer matrix to produce 140 nm diameter fluorescent-ferrite beads (FF beads), which emit at 618 nm. These FF beads were used for immunofluorescent staining for diagnosis of cancer metastases to lymph nodes during cancer resection surgery by labeling tumor cell epidermal growth factor receptor (EGFRs), and for the detection of brain natriuretic peptide (BNP)—a hormone secreted in excess amounts by the heart when stressed—to a level of 2.0 pg ml− 1.

We also describe our work on Hall biosensors made using InSb and GaAs/InGaAs/AlGaAs 2DEG heterostructures integrated with gold current strips to reduce measurement times.

Our approach for the detection of sub-200 nm magnetic bead is also described: we exploit the magnetically induced capture of micrometer sized ‘probe beads’ by nanometer sized ‘target beads’, enabling the detection of small concentrations of beads as small as 8 nm in ‘pumpless’ microcapillary systems.

Finally, we describe a ‘label-less homogeneous’ procedure referred to as ‘magneto-optical transmission (MT) sensing’, where the optical transmission of a solution containing rotating linear chains of magnetic nanobeads was used to detect biomolecules with pM-level sensitivity with a dynamic range of more than four orders of magnitude. Our research on the synthesis and applications of nanoparticles is particularly suitable for point of care diagnostics.
Relative Virulence of Botrytis cinerea and B. mali in Apple Lesions
Authors: Etebarian Reza H. , O'Gorman Daniel T. , Sholberg Peter L.
Published: October 2010

Botrytis cinerea and recently B. mali have been identified as important postharvest pathogens of apples in British Columbia (BC), Canada. Three isolates of both B. cinerea and B. mali were studied alone and in combination by inoculating mature ‘Gala’ apple fruit to compare their potential for causing decay. The fruit were incubated at 20°C for 6 and 8 days when lesion areas were calculated from lesion diameters. The lesion areas in apples inoculated with B. cinerea ranged from 1020 to 1514 mm2 compared to 130 to 293 mm2 for B. mali after 6 days. Primers developed to specifically amplify B. mali or B. cinerea were used in a PCR test to determine which Botrytis spp. was present in a particular lesion and estimate the quantity of each species. Relative fluorescent intensity of DNA extracted from apple tissue co-inoculated with B. cinerea + B. mali and amplified with the B. cinerea specific primer averaged 102.3%. On the other hand, the fluorescence produced by the B. mali primer averaged only 11.6% from the same DNA samples. These results confirmed that when both B. cinerea and B. mali are mixed together, B. cinerea becomes the dominant pathogen.

Accepted for publication 2 July 2010. Published 20 September 2010.
Purinergic P2X Receptor Regulates N -Methyl-d-aspartate Receptor Expression and Synaptic Excitatory Amino Acid Concentration in Morphine-tolerant Rats
Authors: Tai Yueh-Hua , Cheng Pao-Yun , Tsai Ru-Yin , Chen Yuh-Fung , Wong Chih-Shung
Published: October 2010

Background

The present study examined the effect of P2X receptor antagonist 2',3'-O-(2,4,6-trinitrophenyl) adenosine 5'-triphosphate (TNP-ATP) on morphine tolerance in rats.

Methods

Male Wistar rats were implanted with two intrathecal catheters with or without a microdialysis probe, then received a continuous intrathecal infusion of saline (control) or morphine (tolerance induction) for 5 days.

Results

Long-term morphine infusion induced antinociceptive tolerance and up-regulated N-methyl-d-aspartate receptor subunits NR1 and NR2B expression in both total lysate and synaptosome fraction of the spinal cord dorsal horn. TNP-ATP (50 μg) treatment potentiated the antinociceptive effect of morphine, with a 5.5-fold leftward shift of the morphine dose-response curve in morphine-tolerant rats, and this was associated with reversal of the up-regulated NR1 and NR2B subunits in the synaptosome fraction. NR1/NR2B-specific antagonist ifenprodil treatment produced a similar effect as TNP-ATP; it also potentiated the antinociceptive effect of morphine. On day 5, morphine challenge resulted in a significant increase in aspartate and glutamate concentration in the cerebrospinal fluid dialysates of morphine-tolerant rats, and this effect was reversed by TNP-ATP treatment. Moreover, the amount of immunoprecipitated postsynaptic density-95/NR1/NR2B complex was increased in morphine-tolerant rats, and this was prevented by the TNP-ATP treatment.

Conclusions

The findings suggest that attenuation of morphine tolerance by TNP-ATP is attributed to down-regulation of N-methyl-d-aspartate receptor subunits NR1 and NR2B expression in the synaptosomal membrane and inhibition of excitatory amino acids release in morphine-tolerant rats. The TNP-ATP regulation on the N-methyl-d-aspartate receptor expression may be involved in a loss of scaffolding proteins postsynaptic density-95.
Critical Role of the Small GTPase RhoA in the Development of Pulmonary Edema Induced by Pseudomonas aeruginosa in Mice
Authors: Carles Michel , Lafargue Mathieu , Goolaerts Arnaud , Roux Jérémie , Song Yuanlin , Howard Marybeth , Weston David , Swindle John T. , Hedgpeth Joe , Burel-Vandenbos Fanny , Pittet Jean-Francois
Published: October 2010

Background

Pseudomonas aeruginosa is an opportunistic pathogen that can cause severe pneumonia in critically ill patients. We have reported previously that P. aeruginosa exotoxins S and T mediate in vitro the increase in protein permeability across lung endothelial cell monolayers via a RhoA-dependent mechanism. However, whether inhibition of RhoA would significantly attenuate P. aeruginosa-mediated lung injury in mice is unknown.

Methods

P. aeruginosa-induced paracellular protein permeability was measured across bovine lung endothelial and rat alveolar epithelial type II cell monolayers with I-albumin. Some cell monolayers were pretreated with RhoA inhibitor CGX0287 1 h before P. aeruginosa exposure. At 4 h after exposure, lung endothelial and epithelial permeability, bacterial counts, bronchoalveolar lavage fluid levels of keratinocyte-derived chemokine, myeloperoxidase activity, and alveolar fluid clearance were measured. Some mice were treated intraperitoneally with CGX0287 1 h before or after airspace instillation of P. aeruginosa.

Results

RhoA inhibition attenuated in vitro P. aeruginosa-mediated increase in lung endothelial and epithelial permeability to protein and in vivo the development of pulmonary edema and inhibition of alveolar fluid clearance associated with P. aeruginosa pneumonia. Furthermore, RhoA inhibition decreased the systemic dissemination of P. aeruginosa and neutrophil activity in the lung tissue observed after airspace instillation of these bacteria.

Conclusions

The small GTPase RhoA plays a critical role in mediating lung injury associated with P. aeruginosa pneumonia in mice. Thus, transient blockade of RhoA could attenuate lung damage caused by P. aeruginosa in critically ill patients.
Disrupted Sleep and Delayed Recovery from Chronic Peripheral Neuropathy Are Distinct Phenotypes in a Rat Model of Metabolic Syndrome
Authors: Muncey Aaron R. , Saulles Adam R. , Koch Lauren G. , Britton Steven L. , Baghdoyan Helen A. , Lydic Ralph
Published: October 2010

Background

Sleep apnea, hypertension, atherosclerosis, and obesity are features of metabolic syndrome associated with decreased restorative sleep and increased pain. These traits are relevant for anesthesiology because they confer increased risks of a negative anesthetic outcome. This study tested the one-tailed hypothesis that rats bred for low intrinsic aerobic capacity have enhanced nociception and disordered sleep.

Methods

Rats were developed from a breeding strategy that selected for low aerobic capacity runners (LCR) and high aerobic capacity runners (HCR). Four phenotypes were quantified. Rats underwent von Frey sensory testing (n = 12), thermal nociceptive testing (n = 12), electrographic recordings of sleep and wakefulness (n = 16), and thermal nociceptive testing (n = 14) before and for 6 weeks after a unilateral chronic neuropathy of the sciatic nerve.

Results

Paw withdrawal latency to a thermal nociceptive stimulus was significantly (P < 0.01) lower in LCR than HCR rats. There were also significant differences in sleep, with LCR rats spending significantly (P < 0.01) more time awake (18%) and less time in nonrapid eye movement sleep (-19%) than HCR rats. Nonrapid eye movement sleep episodes were of shorter duration (-34%) in LCR than HCR rats. Rapid eye movement sleep of LCR rats was significantly more fragmented than rapid eye movement sleep of HCR rats. LCR rats required 2 weeks longer than HCR rats to recover from peripheral neuropathy.

Conclusions

Rodents with low aerobic capacity exhibit features homologous to human metabolic syndrome. This rodent model offers a novel tool for characterizing the mechanisms through which low aerobic function and obesity might confer increased risks for anesthesia.
Evaluation of Pregabalin as an Adjuvant to Patient-controlled Epidural Analgesia during Late Termination of Pregnancy
Authors: Lavand'homme Patricia M. , Roelants Fabienne
Published: October 2010

Introduction

Late termination of pregnancy combines psychological distress with severe physical pain. The present study evaluated the benefit of adding oral pregabalin to epidural analgesia during this procedure.

Methods

Healthy women were randomly allocated to receive either oral pregabalin 150 mg/12 h or prazepam 10 mg/12 h at the induction of the late termination of pregnancy procedure. When they felt abdominal pain (numerical rating scale ranging from 0 [no pain] to 100 [worst pain possible]), patient-controlled epidural analgesia was activated and set to deliver ropivacaine 0.1% with sufentanil 0.25 μg/ml, 5 ml/h with a bolus dose of 5 ml/30 min. Rescue analgesia was available as needed by administration of 10 ml ropivacaine 0.1% (pain score less than 60/100) or 0.2% (at least 60/100). The primary outcome was the consumption of epidural analgesics.

Results

Forty-eight patients participated in the study. Demographic and obstetric data were similar. Pregabalin reduced total ropivacaine consumption 11.3 ± 3.2 mg/h (mean ± SD) versus 15.1 ± 4.9 mg/h in the prazepam group (P = 0.005), an effect related to a decrease in the need for rescue analgesia. In the pregabalin group, fewer women asked for rescue dose (75 vs. 96%; P = 0.048), and the number of rescue doses per patient was reduced (1 [0-2] vs. 2 [1-3]); median [interquartile range], P = 0.005), particularly the need for ropivacaine 0.2%.

Discussion

This is the first study considering the use of pregabalin for labor pain associated with late termination of pregnancy, showing that pregabalin 150 mg/12 h is a helpful adjuvant to epidural analgesia. Modulation of both visceral sensitization and affective component of pain may contribute to the benefits observed.
Microbulbifer chitinilyticus sp. nov. and Microbulbifer okinawensis sp. nov., chitin-degrading bacteria isolated from mangrove forests
Authors: Baba Atsushi , Miyazaki Masayuki , Nagahama Takahiko , Nogi Yuichi
Published: October 2010

Three chitin-degrading strains representing two novel species were isolated from mangrove forests in Okinawa, Japan. The isolates, ABABA23T, ABABA211 and ABABA212T, were Gram-negative, non-spore-forming, strictly aerobic chemo-organotrophs. The novel strains produced Q-8 as the major isoprenoid quinone component. The predominant fatty acids were iso-C15 : 0 and C16 : 0. On the basis of 16S rRNA gene sequence analysis, the isolates were closely affiliated with members of the genus Microbulbifer. The DNA G+C contents of strains ABABA23T and ABABA212T were 57.8 and 60.2 mol%, respectively. DNA–DNA relatedness values between these two strains and Microbulbifer reference strains were significantly lower than 70 %, the generally accepted threshold level below which strains are considered to belong to separate species. Based on differences in taxonomic characteristics, the three isolates represent two novel species of the genus Microbulbifer, for which the names Microbulbifer chitinilyticus sp. nov. (type strain, ABABA212T = JCM 16148T = NCIMB 14577T) and Microbulbifer okinawensis sp. nov. (type strain, ABABA23T = JCM 16147T = NCIMB 14576T; reference strain, ABABA211) are proposed.
Vibrio stylophorae sp. nov., isolated from the reef-building coral Stylophora pistillata
Authors: Sheu Shih-Yi , Jiang Sing-Rong , Chen Chaolun Allen , Wang Jih-Terng , Chen Wen-Ming
Published: October 2010

A bacterial strain designated KTW-12T was isolated from a reef-building coral in Kenting, Taiwan, and was characterized using a polyphasic taxonomic approach. Strain KTW-12T was Gram-negative, semi-transparent, slightly curved rod-shaped, and non-motile. Growth occurred at 15–35 °C (optimum, 30 °C), at pH 6.0–9.0 (optimum, pH 7.0–8.0), and with 0.5–6.0 % NaCl (optimum, 2 %). The major cellular fatty acids were summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c), C14 : 0 and C16 : 0. The DNA G+C content was 47.8 mol%. Phylogenetic analyses based on 16S rRNA gene sequences indicated that strain KTW-12T was most closely related to Vibrio porteresiae MSSRF30T, with 94.8 % gene sequence similarity. Further multilocus sequence analysis using rpoA, recA and pyrH genes also revealed low levels of sequence similarity (74.6–85.0 %) with all species of the genus Vibrio with validly published names. A multigene phylogenetic tree using concatenated sequences of the four genes (16S rRNA, rpoA, recA and pyrH) elucidated that strain KTW-12T occupied a distinct phylogenetic position, forming a long branch that was not clustered with any other known species of the genus Vibrio. Strain KTW-12T differed from V. porteresiae MSSRF30T in the ability to reduce nitrate to nitrite, hydrolysis of chitin, fermentation of sorbitol and production of arginine dihydrolase, valine arylamidase, cystine arylamidase and N-acetyl-β-glucosaminidase. On the basis of phenotypic, chemotaxonomic and phylogenetic distinctiveness, strain KTW-12T should be classified as representing a novel species, for which the name Vibrio stylophorae sp. nov. is proposed. The type strain is KTW-12T ( = BCRC 80105T  = LMG 25357T).
Marinomonas alcarazii sp. nov., M. rhizomae sp. nov., M. foliarum sp. nov., M. posidonica sp. nov. and M. aquiplantarum sp. nov., isolated from the microbiota of the seagrass Posidonia oceanica
Authors: Lucas-Elío Patricia , Marco-Noales Ester , Espinosa Elena , Ordax Mónica , López María M. , Garcías-Bonet Neus , Marbà Nuria , Duarte Carlos M. , Sanchez-Amat Antonio
Published: October 2010

Five novel Gram-reaction-negative aerobic marine bacterial strains with DNA G+C contents <50 mol% were isolated from the seagrass Posidonia oceanica. 16S rRNA sequence analysis indicated that they belonged to the genus Marinomonas. Major fatty acid compositions, comprising C10 : 0 3-OH, C16 : 0, C16 : 1ω7c and C18 : 1ω7c, supported the affiliation of these strains to the genus Marinomonas. Strains IVIA-Po-14bT, IVIA-Po-145T and IVIA-Po-155T were closely related to Marinomonas pontica 46-16T, according to phylogenetic analysis. However, DNA–DNA hybridization values <35 % among these strains revealed that they represented different species. Further differences in the phenotypes and minor fatty acid compositions were also found among the strains. Another two strains, designated IVIA-Po-181T and IVIA-Po-159T, were found to be closely related to M. dokdonensis DSW10-10T but DNA–DNA relatedness levels <40 % in pairwise comparisons, as well as some additional differences in phenotypes and fatty acid compositions supported the creation of two novel species. Accordingly, strains IVIA-Po-14bT ( = CECT 7730T  = NCIMB 14671T), IVIA-Po-145T ( = CECT 7377T  = NCIMB 14431T), IVIA-Po-155T ( = CECT 7731T  = NCIMB 14672T), IVIA-Po-181T ( = CECT 7376T  = NCIMB 14433T) and IVIA-Po-159T ( = CECT 7732T  = NCIMB 14673T) represent novel species, for which the names Marinomonas alcarazii sp. nov., Marinomonas rhizomae sp. nov., Marinomonas foliarum sp. nov., Marinomonas posidonica sp. nov. and Marinomonas aquiplantarum sp. nov. are proposed, respectively.
Glaciimonas immobilis gen. nov., sp. nov., a member of the family Oxalobacteraceae isolated from alpine glacier cryoconite
Authors: Zhang De-Chao , Redzic Mersiha , Schinner Franz , Margesin Rosa
Published: October 2010

Strains Cr9-30T and Cr9-12 were isolated from alpine glacier cryoconite. Both strains were Gram-negative-staining, non-motile, rod-shaped and psychrophilic, showing good growth over the temperature range 1–20 °C. Phylogenetic analysis of 16S rRNA gene sequences revealed that the two strains formed a distinct branch within the family Oxalobacteraceae and were most closely related to members of the genus Collimonas. The 16S rRNA gene sequence similarity between strains Cr9-30T and Cr9-12 was 99.0 %. The two strains showed highest 16S rRNA gene sequence pairwise similarity with Collimonas pratensis LMG 23965T (96.6 and 96.1 % for strains Cr9-30T and Cr9-12, respectively), Collimonas arenae LMG 23964T (96.5 and 96.3 %, respectively) and Collimonas fungivorans LMG 21973T (96.4 and 96.2 %, respectively). The predominant cellular fatty acids were summed feature 3 (C16 : 1ω7c and/or iso-C15 : 0 2-OH), C16 : 0 and C18 : 1ω7c. The DNA G+C content of strain Cr9-30T was 51.0 mol%. On the basis of phenotypic characteristics and phylogenetic analysis, strains Cr9-30T and Cr9-12 represent a novel species in a new genus of the family Oxalobacteraceae, for which the name Glaciimonas immobilis gen. nov., sp. nov. is proposed. The type strain of Glaciimonas immobilis is Cr9-30T ( = DSM 23240T = LMG 25547T).
Paracoccus stylophorae sp. nov., isolated from the reef-building coral Stylophora pistillata
Authors: Sheu Shih-Yi , Jiang Sing-Rong , Chen Chaolun Allen , Wang Jih-Terng , Chen Wen-Ming
Published: October 2010

A bacterial strain, designated KTW-16T, was isolated from the reef-building coral Stylophora pistillata, collected from southern Taiwan. Strain KTW-16T was a Gram-negative, facultatively anaerobic, pale-yellow, non-motile short rod. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain KTW-16T belonged to the genus Paracoccus in the Alphaproteobacteria and exhibited 93.7–96.9 % 16S rRNA gene sequence similarity with type strains of species of the genus Paracoccus (96.9 % with Paracoccus alcaliphilus JCM 7364T). Strain KTW-16T grew at 15–40 °C (optimum 35 °C), at pH 6.0–10.0 (optimum pH 8.0) and with 0–9 % NaCl (optimum 5 %). The predominant cellular fatty acids were C18 : 1ω7c, C19 : 0 cyclo ω8c and C18 : 0. The major respiratory quinone was Q-10 and the DNA G+C content was 69.1 mol%. The polar lipid profile consisted of phosphatidylglycerol, diphosphatidylglycerol, phosphatidylcholine and several unknown polar lipids. The physiological and biochemical tests allowed clear phenotypic differentiation of the isolate from the type strains of already described Paracoccus species. It is evident from the genotypic, phenotypic and chemotaxonomic analysis that strain KTW-16T should be classified in a novel species of the genus Paracoccus, for which the name Paracoccus stylophorae sp. nov. is proposed. The type strain is KTW-16T ( = LMG 25392T  = BCRC 80106T).
Notch dimerization is required for leukemogenesis and T-cell development
Authors: Liu Hudan , Chi Anthony W.S. , Arnett Kelly L. , Chiang Mark Y. , Xu Lanwei , Shestova Olga , Wang Hongfang , Li Yue-Ming , Bhandoola Avinash , Aster Jon C. , Blacklow Stephen C. , Pear Warren S.
Published: October 2010

Notch signaling regulates myriad cellular functions by activating transcription, yet how Notch selectively activates different transcriptional targets is poorly understood. The core Notch transcriptional activation complex can bind DNA as a monomer, but it can also dimerize on DNA-binding sites that are properly oriented and spaced. However, the significance of Notch dimerization is unknown. Here, we show that dimeric Notch transcriptional complexes are required for T-cell maturation and leukemic transformation but are dispensable for T-cell fate specification from a multipotential precursor. The varying requirements for Notch dimerization result from the differential sensitivity of specific Notch target genes. In particular, c-Myc and pre-T-cell antigen receptor α (Ptcra) are dimerization-dependent targets, whereas Hey1 and CD25 are not. These findings identify functionally important differences in the responsiveness among Notch target genes attributable to the formation of higher-order complexes. Consequently, it may be possible to develop a new class of Notch inhibitors that selectively block outcomes that depend on Notch dimerization (e.g., leukemogenesis).
Next-generation sequencing identifies the natural killer cell microRNA transcriptome
Authors: Fehniger Todd A. , Wylie Todd , Germino Elizabeth , Leong Jeffrey W. , Magrini Vincent J. , Koul Sunita , Keppel Catherine R. , Schneider Stephanie E. , Koboldt Daniel C. , Sullivan Ryan P. , Heinz Michael E. , Crosby Seth D. , Nagarajan Rakesh , Ramsingh Giridharan , Link Daniel C. , Ley Timothy J. , Mardis Elaine R.
Published: October 2010

Natural killer (NK) cells are innate lymphocytes important for early host defense against infectious pathogens and surveillance against malignant transformation. Resting murine NK cells regulate the translation of effector molecule mRNAs (e.g., granzyme B, GzmB) through unclear molecular mechanisms. MicroRNAs (miRNAs) are small noncoding RNAs that post-transcriptionally regulate the translation of their mRNA targets, and are therefore candidates for mediating this control process. While the expression and importance of miRNAs in T and B lymphocytes have been established, little is known about miRNAs in NK cells. Here, we used two next-generation sequencing (NGS) platforms to define the miRNA transcriptomes of resting and cytokine-activated primary murine NK cells, with confirmation by quantitative real-time PCR (qRT-PCR) and microarrays. We delineate a bioinformatics analysis pipeline that identified 302 known and 21 novel mature miRNAs from sequences obtained from NK cell small RNA libraries. These miRNAs are expressed over a broad range and exhibit isomiR complexity, and a subset is differentially expressed following cytokine activation. Using these miRNA NGS data, miR-223 was identified as a mature miRNA present in resting NK cells with decreased expression following cytokine activation. Furthermore, we demonstrate that miR-223 specifically targets the 3′ untranslated region of murine GzmB in vitro, indicating that this miRNA may contribute to control of GzmB translation in resting NK cells. Thus, the sequenced NK cell miRNA transcriptome provides a valuable framework for further elucidation of miRNA expression and function in NK cell biology.
A GlutathioneS-Transferase Regulated by Light and Hormones Participates in the Modulation of Arabidopsis Seedling Development
Authors: Jiang Han-Wei , Liu Ming-Jung , Chen Ing-Chien , Huang Chiung-Huei , Chao Li-Ya , Hsieh Hsu-Liang
Published: October 2010

Glutathione S-transferases (GSTs) have been well documented to be involved in diverse aspects of biotic and abiotic stresses, especially detoxification processes. Whether they regulate plant development remains unclear. Here, we report on our isolation by reverse transcription-polymerase chain reaction of a plant GST, AtGSTU17, from Arabidopsis (Arabidopsis thaliana) and demonstrate that its expression is regulated by multiple photoreceptors, especially phytochrome A (phyA) under all light conditions. Further physiological studies indicated that AtGSTU17 participates in various aspects of seedling development, including hypocotyl elongation, anthocyanin accumulation, and far-red light-mediated inhibition of greening with a requirement of functional phyA. The loss-of-function mutant of AtGSTU17 (atgstu17) resulted in reduced biomass of seedlings and number of lateral roots in the presence of auxin, as well as insensitivity to abscisic acid (ABA)-mediated inhibition of root elongation, with similarity to different phyA mutant alleles. Moreover, the root phenotype conferred by atgstu17 was reflected by histochemical β-glucuronidase staining of AtGSTU17 promoter activity with the addition of auxin or ABA. Further microarray analysis of wild-type Columbia and atgstu17 seedlings treated with far-red irradiation or ABA revealed that AtGSTU17 might modulate hypocotyl elongation by positively regulating some light-signaling components and negatively regulating a group of auxin-responsive genes and modulate root development by negatively controlling an auxin transport protein in the presence of ABA. Therefore, our data reveal that AtGSTU17 participates in light signaling and might modulate various aspects of Arabidopsis development by affecting glutathione pools via a coordinated regulation with phyA and phytohormones.
Essential Role of Glutathione in Acclimation to Environmental and Redox Perturbations in the Cyanobacterium Synechocystis sp. PCC 6803
Authors: Cameron Jeffrey C. , Pakrasi Himadri B.
Published: October 2010

Glutathione, a nonribosomal thiol tripeptide, has been shown to be critical for many processes in plants. Much less is known about the roles of glutathione in cyanobacteria, oxygenic photosynthetic prokaryotes that are the evolutionary precursor of the chloroplast. An understanding of glutathione metabolism in cyanobacteria is expected to provide novel insight into the evolution of the elaborate and extensive pathways that utilize glutathione in photosynthetic organisms. To investigate the function of glutathione in cyanobacteria, we generated deletion mutants of glutamate-cysteine ligase (gshA) and glutathione synthetase (gshB) in Synechocystis sp. PCC 6803. Complete segregation of the ƊgshA mutation was not achieved, suggesting that GshA activity is essential for growth. In contrast, fully segregated ƊgshB mutants were isolated and characterized. The ƊgshB strain lacks reduced glutathione (GSH) but instead accumulates the precursor compound γ-glutamylcysteine (γ-EC). The ƊgshB strain grows slower than the wild-type strain under favorable conditions and exhibits extremely reduced growth or death when subjected to conditions promoting oxidative stress. Furthermore, we analyzed thiol contents in the wild type and the ƊgshB mutant after subjecting the strains to multiple environmental and redox perturbations. We found that conditions promoting growth stimulate glutathione biosynthesis. We also determined that cellular GSH and γ-EC content decline following exposure to dark and blue light and during photoheterotrophic growth. Moreover, a rapid depletion of GSH and γ-EC is observed in the wild type and the ƊgshB strain, respectively, when cells are starved for nitrate or sulfate.
Photoreceptors CRYTOCHROME2 and Phytochrome B Control Chromatin Compaction in Arabidopsis
Authors: van Zanten Martijn , Tessadori Federico , McLoughlin Fionn , Smith Reuben , Millenaar Frank F. , van Driel Roel , Voesenek Laurentius A.C.J. , Peeters Anton J.M. , Fransz Paul
Published: October 2010

Development and acclimation processes to the environment are associated with large-scale changes in chromatin compaction in Arabidopsis (Arabidopsis thaliana). Here, we studied the effects of light signals on chromatin organization. A decrease in light intensity induces a large-scale reduction in chromatin compaction. This low light response is reversible and shows strong natural genetic variation. Moreover, the degree of chromatin compaction is affected by light quality signals relevant for natural canopy shade. The photoreceptor CRYPTOCHROME2 appears a general positive regulator of low light-induced chromatin decompaction. Phytochrome B also controls light-induced chromatin organization, but its effect appears to be dependent on the genetic background. We present a model in which chromatin compaction is regulated by the light environment via CRYPTOCHROME2 protein abundance, which is controlled by phytochrome B action.
Changes in Transcript Abundance in Chlamydomonas reinhardtii following Nitrogen Deprivation Predict Diversion of Metabolism
Authors: Miller Rachel , Wu Guangxi , Deshpande Rahul R. , Vieler Astrid , Gärtner Katrin , Li Xiaobo , Moellering Eric R. , Zäuner Simone , Cornish Adam J. , Liu Bensheng , Bullard Blair , Sears Barbara B. , Kuo Min-Hao , Hegg Eric L. , Shachar-Hill Yair , Shiu Shin-Han , Benning Christoph
Published: October 2010

Like many microalgae, Chlamydomonas reinhardtii forms lipid droplets rich in triacylglycerols when nutrient deprived. To begin studying the mechanisms underlying this process, nitrogen (N) deprivation was used to induce triacylglycerol accumulation and changes in developmental programs such as gametogenesis. Comparative global analysis of transcripts under induced and noninduced conditions was applied as a first approach to studying molecular changes that promote or accompany triacylglycerol accumulation in cells encountering a new nutrient environment. Towards this goal, high-throughput sequencing technology was employed to generate large numbers of expressed sequence tags of eight biologically independent libraries, four for each condition, N replete and N deprived, allowing a statistically sound comparison of expression levels under the two tested conditions. As expected, N deprivation activated a subset of control genes involved in gametogenesis while down-regulating protein biosynthesis. Genes for components of photosynthesis were also down-regulated, with the exception of the PSBS gene. N deprivation led to a marked redirection of metabolism: the primary carbon source, acetate, was no longer converted to cell building blocks by the glyoxylate cycle and gluconeogenesis but funneled directly into fatty acid biosynthesis. Additional fatty acids may be produced by membrane remodeling, a process that is suggested by the changes observed in transcript abundance of putative lipase genes. Inferences on metabolism based on transcriptional analysis are indirect, but biochemical experiments supported some of these deductions. The data provided here represent a rich source for the exploration of the mechanism of oil accumulation in microalgae.
The Arabidopsis PR-1 Promoter Contains Multiple Integration Sites for the Coactivator NPR1 and the Repressor SNI1
Authors: Pape Sebastian , Thurow Corinna , Gatz Christiane
Published: October 2010

Systemic acquired resistance is a broad-spectrum plant immune response involving massive transcriptional reprogramming. The Arabidopsis (Arabidopsis thaliana) PATHOGENESIS-RELATED-1 (PR-1) gene has been used in numerous studies to elucidate transcriptional control mechanisms regulating systemic acquired resistance. WRKY transcription factors and basic leucine zipper proteins of the TGA family regulate the PR-1 promoter by binding to specific cis-elements. In addition, the promoter is under the control of two proteins that do not directly contact the DNA: the positive regulator NONEXPRESSOR OF PR GENES1 (NPR1), which physically interacts with TGA factors, and the repressor SUPPRESSOR OF NPR1, INDUCIBLE1 (SNI1). In this study, we analyzed the importance of the TGA-binding sites LS5 and LS7 and the WKRY box LS4 for regulation by NPR1 and SNI1. In the absence of LS5 and LS7, NPR1 activates the PR-1 promoter through a mechanism that requires LS4. Since transcriptional activation of WRKY genes is under the control of NPR1 and since LS4 is not sufficient for the activation of a truncated PR-1 promoter by the effector protein NPR1-VP16 in transient assays, it is concluded that the LS4-dependent activation of the PR-1 promoter is indirect. In the case of NPR1 acting directly through TGA factors at its target promoters, two TGA-binding sites are necessary but not sufficient for NPR1 function in transgenic plants and in the NPR-VP16-based trans-activation assay in protoplasts. SNI1 exerts its negative effect in the noninduced state by targeting unknown proteins associated with sequences between bp −816 and −573. Under induced conditions, SNI1 negatively regulates the function of WRKY transcription factors binding to WKRY boxes between bp −550 and −510.
Arachidonic Acid: An Evolutionarily Conserved Signaling Molecule Modulates Plant Stress Signaling Networks
Authors: Savchenko Tatyana , Walley Justin W. , Chehab E. Wassim , Xiao Yanmei , Kaspi Roy , Pye Matthew F. , Mohamed Maged E. , Lazarus Colin M. , Bostock Richard M. , Dehesh Katayoon
Published: October 2010

Fatty acid structure affects cellular activities through changes in membrane lipid composition and the generation of a diversity of bioactive derivatives. Eicosapolyenoic acids are released into plants upon infection by oomycete pathogens, suggesting they may elicit plant defenses. We exploited transgenic Arabidopsis thaliana plants (designated EP) producing eicosadienoic, eicosatrienoic, and arachidonic acid (AA), aimed at mimicking pathogen release of these compounds. We also examined their effect on biotic stress resistance by challenging EP plants with fungal, oomycete, and bacterial pathogens and an insect pest. EP plants exhibited enhanced resistance to all biotic challenges, except they were more susceptible to bacteria than the wild type. Levels of jasmonic acid (JA) were elevated and levels of salicylic acid (SA) were reduced in EP plants. Altered expression of JA and SA pathway genes in EP plants shows that eicosapolyenoic acids effectively modulate stress-responsive transcriptional networks. Exogenous application of various fatty acids to wild-type and JA-deficient mutants confirmed AA as the signaling molecule. Moreover, AA treatment elicited heightened expression of general stress-responsive genes. Importantly, tomato (Solanum lycopersicum) leaves treated with AA exhibited reduced susceptibility to Botrytis  cinerea infection, confirming AA signaling in other plants. These studies support the role of AA, an ancient metazoan signaling molecule, in eliciting plant stress and defense signaling networks.
Mitochondrial β-Cyanoalanine Synthase Is Essential for Root Hair Formation inArabidopsis thaliana
Authors: García Irene , Castellano José María , Vioque Blanca , Solano Roberto , Gotor Cecilia , Romero Luis C.
Published: October 2010

Cyanide is stoichiometrically produced as a coproduct of the ethylene biosynthesis pathway and is detoxified by β-cyanoalanine synthase enzymes. The molecular and phenotypical analysis of T-DNA insertion mutants of the mitochondrial β-cyanoalanine synthase CYS-C1 suggests that discrete accumulation of cyanide is not toxic for the plant and does not alter mitochondrial respiration rates but does act as a strong inhibitor of root hair development. The cys-c1 null allele is defective in root hair formation and accumulates cyanide in root tissues. The root hair defect is phenocopied in wild-type plants by the exogenous addition of cyanide to the growth medium and is reversed by the addition of hydroxocobalamin or by genetic complementation with the CYS-C1 gene. Hydroxocobalamin not only recovers the root phenotype of the mutant but also the formation of reactive oxygen species at the initial step of root hair tip growth. Transcriptional profiling of the cys-c1 mutant reveals that cyanide accumulation acts as a repressive signal for several genes encoding enzymes involved in cell wall rebuilding and the formation of the root hair tip as well as genes involved in ethylene signaling and metabolism. Our results demonstrate that mitochondrial β-cyanoalanine synthase activity is essential to maintain a low level of cyanide for proper root hair development.
Volunteering and the evolution to community action learning
Authors: Perigo Julie
Published: October 2010

Purpose

The purpose of this paper is to explore and explain the benefits of centring learning and development initiatives around charity projects, whether as part of an organisation's community engagement/corporate social responsibility (CSR) strategy and/or as a sensible way to pool internal budgets for practical and identifiable return on investment (community action learning). It also aims to highlight the importance of understanding both the business' and the charities' motivations, expectations and capabilities about the process, in order to maximise success for all parties.

Design/methodology/approach

The paper examines the range of benefits of choosing charity or community projects as a “live” vehicle for learning and development, then identifies common misconceptions, assumptions and mismanagement issues concerning the charity project‐learning link, and offers helpful strategies to gain the best outcomes for all parties concerned.

Findings

There is a growing interest in the value of action learning, in CSR and community engagement, and in developing leaders who recognise the responsibility for how their business activities impact on society and the environment. However, the option to link them all through charity projects is still under‐utilised, and commonly misunderstood and mismanaged. This paper demonstrates that there are methodologies and best practice that can be employed, by both charities and commercial organisations, which break through preconceived ideas about the concept and gain the best tangible results all round.

Originality/value

In times of recession, combining community engagement with solid learning and performance outcomes offers potential cost and resource savings, and ongoing justification for activities which go well beyond traditional “volunteering”. The paper explodes a number of myths and dysfunctional thinking about the business‐charity relationship. In good economic times or bad, this approach helps to weave CSR principles and practice into the mainstream activities of a business. It is an approach that should have particular appeal to organisations keen to develop inspirational leadership which reaches well beyond the office or factory doors.
Do we reinvent ourselves actually?
Authors: McGreevy Malcolm
Published: October 2010

Purpose

Examining the way that individuals adapt to job change is one of the central aims of this paper.

Design/methodology/approach

The factors and processes relating to job loss and outplacement among managers in the UK are examined and compared through identifying trends and cross‐sectional differences in managerial job losses among different industries, companies and individuals. This is undertaken by means of a questionnaire followed up by face‐to‐face interviews or telephone interviews using a semi‐structured questionnaire with analysis.

Findings

The evidence demonstrates that individuals generally are extremely conservative and tend to stick to what they know rather than take the risk of the unknown or untried. What is perhaps more significant, is that 47 per cent of those that obtained work in the same field were in the age group 40‐49 whereas only 31 per cent of the 50‐59 age group were employed in the same field.

Practical implications

More generally, the research underpinning this paper provides insights into the demographics of managerial job loss. It analyses the redundancy process over time; distinguishes between the transition from secure to insecure employment and from insecure to equally insecure employment and ascertains trends over a five‐year period; examines the extent to which managers lose the ability to plan and control their lives and attempts to link this to their individual predisposition and finally determines how managers are likely to respond or operate in a new employment environment.

Originality/value

The research makes use of totally new and original material drawn from the experience of people change careers with outplacement support from two of the leading outplacement companies in the UK.
Four stage approach to organisational talent development (part 2)
Authors: Newbold Colin
Published: October 2010

Purpose

The purpose of this paper is to explain a proven systematic approach to organisational talent development (OTD).

Design/methodology/approach

The work of psychology‐based consultancy The Learning Curve (TLC), their four‐stage process, and two case studies is used as a basis to demonstrate the importance of a sequential plan to develop talent inside an organisation.

Findings

Productivity and profit increase in organisations that embrace a systematic approach to talent development.

Practical implications

Many of the methods employed by TLC have led to engagement and retention of the best staff among clients, who go on to sustain the talent development in cost‐effective ways.

Originality/value

The paper takes a holistic look at the challenge of engaging and retaining good staff, while recognising the importance of budgetary and resource constraints as we slowly come out of recession.
Talent management and its technological partners
Authors: Little Bob
Published: October 2010

Purpose

The purpose of this paper is to provide an overview of the development of talent management systems and their evolving relationship with learning management systems (LMS) and learning content management systems (LCMS).

Design/methodology/approach

The paper uses factual reporting to provide the overview.

Findings

While the traditional LMS is in decline, the LCMS has much in common with – and can augment – a talent management system. Technological developments (cloud computing, PaaS and so on) are having an effect on these relationships.

Practical implications

Talent management systems are becoming increasingly important for would‐be successful large (especially multi‐national) companies. The capacity and the business requirements of the LMS are changing. The LCMS offers a number of advantages for the modern business over the LMS and can collaborate with a talent management system to achieve strategic business objectives. Competency data – and competency management – lie at the heart of building competitive advantage in the modern business world.

Originality/value

This is the first such analysis of the development of talent management systems and their evolving relationship with LMS and LCMS in relation to the corporate learning sector. This paper will be of interest to those looking for: a historical perspective on talent management system development; an explanation of talent management and its place within business strategy, and/or the latest technology developments (mid‐2010) in this sector.
Improving delivery and content through technology and collaboration
Authors: Toms Jeff
Published: October 2010

Purpose

The paper seeks to examine how both training partnerships and innovation technology provide the scope to deliver programmes that offer better value for money, more relevant content and more easily accessible training resources.

Design methodology/approach

The paper looks at how technology and training partnerships are positive news for client organisations as standards of training will ultimately be pushed higher and return on investment will become more transparent, for the good of the industry as a whole.

Findings

The current economic situation has inevitably resulted in training budgets being cut. Some training organisations have responded by partnering and pooling resources to offer more tailored course content and some now offer remote delivery. The paper looks at the advantages of each innovation.

Practical implications

The paper encourages client companies and training organisations to be more innovative in their approach to training given the current economic climate.

Originality/value

The paper is valuable to training organisations and client companies as it explores the potential of remote delivery and training partnerships to improve standards overall.
Effective time management for improved performance
Authors: Jones Lyndon , Hood Penny
Published: October 2010

Purpose

The paper aims to consider how effective time management can lead to improved personal and organisational performance.

Design/methodology/approach

The paper draws on the collective experience of the authors. The relationship between culture and chronicity is explained with reference to working styles. It deals with the notion of time and time span with regard to new technologies, and how these may impact on concentration, face‐to‐face communication and styles of learning. It discusses the importance of effective systems and task management, along with decision making. Finally, the paper addresses time issues pertaining to e‐mail.

Findings

The paper finds that the nature of information has changed from face‐to‐face to staring at computer screens. Research shows that over one‐quarter of recipients of e‐mails misunderstood the communication, even where those interacting are close colleagues, while research at three US business schools found that colleagues were more likely to be dishonest with one another when using e‐mail because of the lack of face‐to‐face interaction. Studies have also shown that business teams co‐operate less if they have not talked face‐to‐face.

Originality/value

The paper will be of relevance to all those working under time constraints in various cultural settings.
The tribological behavior of bismuth dithiophosphate as water‐based additive in aluminium alloy tapping
Authors: Fang Jian , Xia Yanqiu , Liu Weimin
Published: October 2010

Purpose

The purpose of this paper is to study the tribological behavior and mechanism of water‐soluble bismuth dithiophosphate as the additive of water‐based cutting fluid in aluminum alloy tapping.

Design/methodology/approach

Comparable investigation has been made on the lubrication performance of bismuth dithiophosphate and sodium dithiophosphate in aluminum alloy tapping. The aluminum alloy‐machined surface finish was observed on scanning electron microscope. The films on the work‐piece‐machined surface and the tap tool working surface were analyzed by X‐ray photoelectron spectroscopy.

Findings

The results indicated that the water medium containing 1 wt% the prepared water‐soluble bismuth dithiophosphate exhibited better tapping efficiency than the liquid paraffin containing 2.5 wt% chlorinated paraffin and 2.5 wt% sulfurized olefin. The bismuth sulfide component in the reaction film on the tap working surface plays a leading role in elevating the tapping efficiency and improving the machined surface finish.

Research limitations/implications

The paper is restricted to the lubrication performance of bismuth dithiophosphate as the water‐based cutting fluid additive in 2024 aluminum alloy tapping.

Practical implications

The test method adopted is very close to the machined method applied in industry. The test results show that the bismuth dithiophosphate can obviously improve the tapping efficiency and the machined surface finish. Thus, it can be applied to the aluminum alloy cutting in automotive and aviation.

Originality/value

An attempt has been made to identify the chemical reaction film sourced from bismuth element and dithiophosphate group on the work‐piece‐machined surface and the tool working surface and their contribution to enhancing the tapping efficiency and improving the machining surface finish. This is helpful to the designers and the practitioners of the additives of metalworking fluid.