bluuebunny/crossref_metadata_2025 huggingface dataset:
Homologous high-throughput expression and purification of highly conserved E coli proteins
Authors: Ergin Asgar , Büssow Konrad , Sieper Joachim , Thiel Andreas , Duchmann Rainer , Adam Thomas
Published: June 2007

Background

Genetic factors and a dysregulated immune response towards commensal bacteria contribute to the pathogenesis of Inflammatory Bowel Disease (IBD). Animal models demonstrated that the normal intestinal flora is crucial for the development of intestinal inflammation. However, due to the complexity of the intestinal flora, it has been difficult to design experiments for detection of proinflammatory bacterial antigen(s) involved in the pathogenesis of the disease. Several studies indicated a potential association of E. coli with IBD. In addition, T cell clones of IBD patients were shown to cross react towards antigens from different enteric bacterial species and thus likely responded to conserved bacterial antigens. We therefore chose highly conserved E. coli proteins as candidate antigens for abnormal T cell responses in IBD and used high-throughput techniques for cloning, expression and purification under native conditions of a set of 271 conserved E. coli proteins for downstream immunologic studies.

Results

As a standardized procedure, genes were PCR amplified and cloned into the expression vector pQTEV2 in order to express proteins N-terminally fused to a seven-histidine-tag. Initial small-scale expression and purification under native conditions by metal chelate affinity chromatography indicated that the vast majority of target proteins were purified in high yields. Targets that revealed low yields after purification probably due to weak solubility were shuttled into Gateway (Invitrogen) destination vectors in order to enhance solubility by N-terminal fusion of maltose binding protein (MBP), N-utilizing substance A (NusA), or glutathione S-transferase (GST) to the target protein. In addition, recombinant proteins were treated with polymyxin B coated magnetic beads in order to remove lipopolysaccharide (LPS). Thus, 73% of the targeted proteins could be expressed and purified in large-scale to give soluble proteins in the range of 500 μg.

Conclusion

Here, we report a cost-efficient procedure to produce around 200 soluble recombinant E. coli proteins in large-scale, including removal of LPS by polymyxin B coated beads for subsequent use of the proteins in downstream immunological studies.
Androgen-regulated genes differentially modulated by the androgen receptor coactivator L-dopa decarboxylase in human prostate cancer cells
Authors: Margiotti Katia , Wafa Latif A , Cheng Helen , Novelli Giuseppe , Nelson Colleen C , Rennie Paul S
Published: June 2007

Background

The androgen receptor is a ligand-induced transcriptional factor, which plays an important role in normal development of the prostate as well as in the progression of prostate cancer to a hormone refractory state. We previously reported the identification of a novel AR coactivator protein, L-dopa decarboxylase (DDC), which can act at the cytoplasmic level to enhance AR activity. We have also shown that DDC is a neuroendocrine (NE) marker of prostate cancer and that its expression is increased after hormone-ablation therapy and progression to androgen independence. In the present study, we generated tetracycline-inducible LNCaP-DDC prostate cancer stable cells to identify DDC downstream target genes by oligonucleotide microarray analysis.

Results

Comparison of induced DDC overexpressing cells versus non-induced control cell lines revealed a number of changes in the expression of androgen-regulated transcripts encoding proteins with a variety of molecular functions, including signal transduction, binding and catalytic activities. There were a total of 35 differentially expressed genes, 25 up-regulated and 10 down-regulated, in the DDC overexpressing cell line. In particular, we found a well-known androgen induced gene,TMEPAI, which wasup-regulated in DDC overexpressing cells, supporting its known co-activation function. In addition, DDC also further augmented the transcriptional repression function of AR for a subset of androgen-repressed genes. Changes in cellular gene transcription detected by microarray analysis were confirmed for selected genes by quantitative real-time RT-PCR.

Conclusion

Taken together, our results provide evidence for linking DDC action with AR signaling, which may be important for orchestrating molecular changes responsible for prostate cancer progression.
Cytochrome P450arom, androgen and estrogen receptors in pig sperm
Authors: Rago Vittoria , Aquila Saveria , Panza Rocco , Carpino Amalia
Published: June 2007

Background

Androgens and estrogens are crucial for mammalian sperm differentiation but their role in biology of mature male gamete is not still defined. The expression of proteins involved in the biosynthesis and action of these steroid hormones has been demonstrated in human spermatozoa, but very few data have been reported in mature sperm from non human species. The purpose of the current study was to investigate the expression of aromatase (P450arom), estrogen (ERalpha/ERbeta) and androgen (AR) receptors in ejaculated spermatozoa of pig.

Methods

The immunfluorescence experiments were carried out treating pig sperm with anti-P450arom, anti-ERalpha, anti-ERbeta and anti-AR as primary antibodies, while Texas-Red/FITC conjugated IgG were applied as secondary antibodies. Furthermore, Western blot analysis was performed on sperm lysates.

Results

Aromatase was immunolocalized in the sperm tail, ERalpha and AR were localised in the sperm midpiece, while ERbeta was confined in the acrosomal region of the male gamete. Immunoblots detected a ~52 kDa aromatase band, a ~110 kDa AR band, a ~67 kDa ERalpha and two ERbeta bands, at ~50 kDa and ~59 kDa.

Conclusion

This is the first report demonstrating that pig ejaculated spermatozoa express aromatase, estrogen and androgen receptors with a differential intra-cellular localization revealing a specie-specific expression pattern. Therefore, pig sperm could be considered as a potential estrogen source while the different hormone cellular sites suggest distinct roles of androgens and estrogens in pig sperm physiology.
Expression pattern analysis of transcribed HERV sequences is complicated by ex vivorecombination
Authors: Flockerzi Aline , Maydt Jochen , Frank Oliver , Ruggieri Alessia , Maldener Esther , Seifarth Wolfgang , Medstrand Patrik , Lengauer Thomas , Meyerhans Andreas , Leib-Mösch Christine , Meese Eckart , Mayer Jens
Published: June 2007

Background

The human genome comprises numerous human endogenous retroviruses (HERVs) that formed millions of years ago in ancestral species. A number of loci of the HERV-K(HML-2) family are evolutionarily much younger. A recent study suggested an infectious HERV-K(HML-2) variant in humans and other primates. Isolating such a variant from human individuals would be a significant finding for human biology.

Results

When investigating expression patterns of specific HML-2 proviruses we encountered HERV-K(HML-2) cDNA sequences without proviral homologues in the human genome, named HERV-KX, that could very well support recently suggested infectious HML-2 variants. However, detailed sequence analysis, using the software RECCO, suggested that HERV-KX sequences were produced by recombination, possibly arising ex vivo, between transcripts from different HML-2 proviral loci.

Conclusion

As RT-PCR probably will be instrumental for isolating an infectious HERV-K(HML-2) variant, generation of "new" HERV-K(HML-2) sequences by ex vivo recombination seems inevitable. Further complicated by an unknown amount of allelic sequence variation in HERV-K(HML-2) proviruses, newly identified HERV-K(HML-2) variants should be interpreted very cautiously.
Detection of virus mRNA within infected host cells using an isothermal nucleic acid amplification assay: marine cyanophage gene expression within Synechococcus sp
Authors: Wharam Susan D , Hall Matthew J , Wilson William H
Published: June 2007

Background

Signal-Mediated Amplification of RNA Technology (SMART) is an isothermal nucleic acid amplification technology, developed for the detection of specific target sequences, either RNA (for expression) or DNA. Cyanophages are viruses that infect cyanobacteria. Marine cyanophages are ubiquitous in the surface layers of the ocean where they infect members of the globally important genus Synechococcus.

Results

Here we report that the SMART assay allowed us to differentiate between infected and non-infected host cultures. Expression of the cyanophage strain S-PM2 portal vertex gene (g20) was detected from infected host Synechococcus sp. WH7803 cells. Using the SMART assay, we demonstrated that g20 mRNA peaked 240 – 360 minutes post-infection, allowing us to characterise this as a mid to late transcript. g20 DNA was also detected, peaking 10 hours post-infection, coinciding with the onset of host lysis.

Conclusion

The SMART assay is based on isothermal nucleic acid amplification, allowing the detection of specific sequences of DNA or RNA. It was shown to be suitable for differentiating between virus-infected and non-infected host cultures and for the detection of virus gene expression: the first reported use of this technology for such applications.
Clearance of an immunosuppressive virus from the CNS coincides with immune reanimation and diversification
Authors: Lauterbach Henning , Truong Phi , McGavern Dorian B
Published: June 2007

Once a virus infection establishes persistence in the central nervous system (CNS), it is especially difficult to eliminate from this specialized compartment. Therefore, it is of the utmost importance to fully understand scenarios during which a persisting virus is ultimately purged from the CNS by the adaptive immune system. Such a scenario can be found following infection of adult mice with an immunosuppressive variant of lymphocytic choriomeningitis virus (LCMV) referred to as clone 13. In this study we demonstrate that following intravenous inoculation, clone 13 rapidly infected peripheral tissues within one week, but more slowly inundated the entire brain parenchyma over the course of a month. During the establishment of persistence, we observed that genetically tagged LCMV-specific cytotoxic T lymphocytes (CTL) progressively lost function; however, the severity of this loss in the CNS was never as substantial as that observed in the periphery. One of the most impressive features of this model system is that the peripheral T cell response eventually regains functionality at ~60–80 days post-infection, and this was associated with a rapid decline in virus from the periphery. Coincident with this "reanimation phase" was a massive influx of CD4 T and B cells into the CNS and a dramatic reduction in viral distribution. In fact, olfactory bulb neurons served as the last refuge for the persisting virus, which was ultimately purged from the CNS within 200 days post-infection. These data indicate that a functionally revived immune response can prevail over a virus that establishes widespread presence both in the periphery and brain parenchyma, and that therapeutic enhancement of an existing response could serve as an effective means to thwart long term CNS persistence.
Neuronal Mechanism for Neuropathic Pain
Authors: Zhuo Min
Published: June 2007

Among different forms of persistent pain, neuropathic pain presents as a most difficult task for basic researchers and clinicians. Despite recent rapid development of neuroscience and modern techniques related to drug discovery, effective drugs based on clear basic mechanisms are still lacking. Here, I will review the basic neuronal mechanisms that maybe involved in neuropathic pain. I will present the problem of neuropathic pain as a rather difficult task for neuroscientists, and we may have to wait for a long time before we fully understand how brain encode, store, and retrieve painful information after the injury. I propose that neuropathic pain as a major brain disease, rather being a clinic problem due to peripheral injury.
Matching Receptome Genes with Their Ligands for Surveying Paracrine/Autocrine Signaling Systems
Authors: Ben-Shlomo Izhar , Rauch Rami , Avsian-Kretchmer Orna , Hsueh Aaron J. W.
Published: June 2007

Sequencing of genomes from diverse organisms facilitates studies on the repertoire of genes involved in intercellular signaling. Extending previous efforts to annotate most human plasma membrane receptors in the Human Plasma Membrane Receptome database, we matched cognate ligands with individual receptors by surveying the published literature. In the updated online database we called “liganded receptome,” users can search for individual ligands or receptors to reveal their pairing partners and browse through receptor or ligand families to identify relationships between ligands and receptors in their respective families. Because local signaling systems are prevalent in diverse normal and diseased tissues, we used the liganded receptome knowledgebase to interrogate DNA microarray datasets for genome-wide analyses of potential paracrine/autocrine signaling systems. In addition to viewing ligand-receptor coexpression based on precomputed DNA microarray data, users can submit their own microarray data to perform online genome-wide searches for putative paracrine/autocrine signaling systems. Investigation of transcriptome data based on liganded receptome allows the discovery of paracrine/autocrine signaling for known ligand-receptor pairs in previously uncharacterized tissues or developmental stages. The present annotation of ligand-receptor pairs also identifies orphan receptors and ligands without known interacting partners in select families. Because hormonal ligands within the same family usually interact with paralogous receptors, this genomic approach could also facilitate matching of orphan receptors and ligands. The liganded receptome is accessible at http://receptome.stanford.edu.
Coactivation of Janus Tyrosine Kinase (Jak)1 Positively Modulates Prolactin-Jak2 Signaling in Breast Cancer: Recruitment of ERK and Signal Transducer and Activator of Transcription (Stat)3 and Enhancement of Akt and Stat5a/b Pathways
Authors: Neilson Lynn M. , Zhu Jianquong , Xie Jianwu , Malabarba M. Grazia , Sakamoto Kazuhito , Wagner Kay-Uwe , Kirken Robert A. , Rui Hallgeir
Published: June 2007

Prolactin (PRL) receptors (PRLRs) have been considered selective activators of Janus tyrosine kinase (Jak)2 but not Jak1, Jak3, or Tyk2. We now report marked PRL-induced tyrosine phosphorylation of Jak1, in addition to Jak2, in a series of human breast cancer cell lines, including T47D, MCF7, and SKBR3. In contrast, PRL did not activate Jak1 in immortalized, noncancerous breast epithelial lines HC11, MCF10A, ME16C, and HBL-100, or in CWR22Rv1 prostate cancer cells or MDA-MB-231 breast cancer cells. However, introduction of exogenous PRLR into MCF10A, ME16C, or MDA-MB-231 cells reconstituted both PRL-Jak1 and PRL-Jak2 signals. In vitro kinase assays verified that PRL stimulated enzymatic activity of Jak1 in T47D cells, and PRL activated Jak1 and Jak2 with indistinguishable time and dose kinetics. Relative Jak2 deficiency did not cause PRLR activation of Jak1, because overexpression of Jak2 did not interfere with PRL activation of Jak1. Instead, PRL activated Jak1 through a Jak2-dependent mechanism, based on disruption of PRL activation of Jak1 after Jak2 suppression by 1) lentiviral delivery of Jak2 short hairpin RNA, 2) adenoviral delivery of dominant-negative Jak2, and 3) AG490 pharmacological inhibition. Finally, suppression of Jak1 by lentiviral delivery of Jak1 short hairpin RNA blocked PRL activation of ERK and signal transducer and activator of transcription (Stat)3 and suppressed PRL activation of Jak2, Stat5a, Stat5b, and Akt, as well as tyrosine phosphorylation of PRLR. The data suggest that PRL activation of Jak1 represents a novel, Jak2-dependent mechanism that may serve as a regulatory switch leading to PRL activation of ERK and Stat3 pathways, while also serving to enhance PRL-induced Stat5a/b and Akt signaling.
The effect of cellular cholesterol on membrane-cytoskeleton adhesion
Authors: Sun Mingzhai , Northup Nathan , Marga Francoise , Huber Tamas , Byfield Fitzroy J. , Levitan Irena , Forgacs Gabor
Published: June 2007

Whereas recent studies suggest that cholesterol plays important role in the regulation of membrane proteins, its effect on the interaction of the cell membrane with the underlying cytoskeleton is not well understood. Here, we investigated this by measuring the forces needed to extract nanotubes (tethers) from the plasma membrane, using atomic force microscopy. The magnitude of these forces provided a direct measure of cell stiffness, cell membrane effective surface viscosity and association with the underlying cytoskeleton. Furthermore, we measured the lateral diffusion constant of a lipid analog DiIC12, using fluorescence recovery after photobleaching, which offers additional information on the organization of the membrane. We found that cholesterol depletion significantly increased the adhesion energy between the membrane and the cytoskeleton and decreased the membrane diffusion constant. An increase in cellular cholesterol to a level higher than that in control cells led to a decrease in the adhesion energy and the membrane surface viscosity. Disassembly of the actin network abrogated all the observed effects, suggesting that cholesterol affects the mechanical properties of a cell through the underlying cytoskeleton. The results of these quantitative studies may help to better understand the biomechanical processes accompanying the development of atherosclerosis.
Visual Detection of Cyanide through Intramolecular Hydrogen Bond
Authors: Lee Kyung-Sik , Lee Jong Tak , Hong Jong-In , Kim Hae-Jo
Published: June 2007

An azo compound based on salicylaldehyde displays a red color upon binding to the cyanide anion with micromolar sensitivity. The high affinity is caused by an intramolecular hydrogen bond of phenol hydrogen to carbonyl oxygen, which stabilizes the anionic character of the intermediate during the nucleophilic attack of a cyanide anion.
A rearing system for colostrum-deprived neonatal piglets
Authors: Varley M. A. , Fowler V. R. , Maitland Alison
Published: June 2007

A system for the artificial rearing of colostrum-deprived neonatal piglets is described. A total of 443 piglets in 6 batches was reared. Each piglet, immediately after birth was placed in a separate incubator which was ventilated with heated filtered air. Piglets were fed hourly by an automatic system and were offered a liquid milk substitute. The mean survival rate up to the time piglets were transferred out of the rearing unit at 2 weeks of age was 78 ± 7%. The mean daily live weight gain up to 2 weeks of age was 148 ± 16 g/day and the dry matter intake over the same period was 154 ± 10 g/day per piglet.
NIH/Ola: a highly productive inbred strain of laboratory mouse
Authors: Peters A. G. , Festing M. F. W.
Published: June 2007

According to historical records the NIH/Ola strain was developed from outbred 'Swiss' mice imported into the USA by Dr C. Lynch in 1926. A comparison of biochemical markers in strain NIH/Ola and other strains such as SJL and SWR derived from the same foundation stock supports the historical records. Data on litter size, length of gestation, bodyweight to 70 days of age, and reproductive performance when housed in polygamous groups of up to 10 females per male were compared with similar data on inbred CBA/CaOla and CS7BL/10ScSnOla mice. NIH/Ola inbred mice had an exceptional reproductive performance, producing about 1·8 young weaned/female/week when housed as monogamous pairs over a period of 20 weeks, compared with less than 1·0 young/female/week with the other 2 strains. NIH/Ola mice were also extremely tolerant to mating in polygamous groups of up to about 8 females per male. Mating ratios of over 2-3 females per male resulted in a marked decline in the total number of litters produced per female in C57BL/10ScSnOla and CBA/CaOla, but this reduction was not nearly so marked in NIH/Ola. It is concluded that the NIH/Ola inbred strain may be particularly useful in studies such as teratology where a high reproductive performance needs to be combined with the advantages of a fully inbred strain.
Naturally occurring genital mycoplasmosis in mice
Authors: Banerjee A. K. , Angulo A. F. , Polak-Vogelzang A. A. , Kershof A. M.
Published: June 2007

The first isolations of Mycoplasma pulmonis were made from inflamed ovaries of 2 C3H/F1 mice. Investigation of cultures from a further 110 apparently healthy mice revealed 14 cases of M. pulmonis localized in the ovaries and associated with oophoritis.
The use of a silastic shield to protect an externalized biliary cannula
Authors: Kanz M. F. , Vanoye-Trevino C. , Moslen M. T.
Published: June 2007

A simple shield made of a folded silastic sheet is described for the protection of the externalized portion of a permanent biliary cannula in rats. Advantages of this shield are its light weight, flexibility, transparency, and ease of resealing for repeated interruption of hepatobiliary circulation. Since the shield is positioned around rather than being a segment of the cannula, a single length of tubing can be used.
Environmental Impact of Detonation of Explosives in Seismic Survey Operations
Authors: Singh Rakesh K. , Sawmliana Chhangte , Roy Pijush Pal , Dasgupta Rahul
Published: June 2007

Seismic survey operations are short-term, although, they can cause annoyance to the surrounding inhabitants. These annoyances may be due to generation of ground vibrations and noise and their possible impact on the surrounding houses and other structures. The paper discusses a case study of experimental trials conducted at three different exploration sites of Oil India Limited in Assam, India. The impact of ground vibrations and noise generated due to detonation of explosives were investigated on the surrounding environment and structures in various working conditions. The maximum magnitude of vibration recorded near a residential house was 53.01 mm/s at a distance of 20 m from the blast site with the dominant peak frequency of 56.8 Hz. No adverse impact on the structure was observed. The analyses of data revealed that the ground vibrations generated due to the detonation of explosives were having their most of the energy in higher dominant frequency bands i.e. more than 30 Hz. The analyses of data clearly indicated that the magnitude of ground vibration enhances when the shot holes are stemmed. In general, the enhancement in vibration was 9–29 % but in some cases, it was observed up to 31.7 %. The level of vibration also increases as the depth of burial of explosives is increased. It was observed that whenever the confinement of explosives will be more, higher magnitude of vibrations would be generated. The magnitude of noise generated during seismic survey operations were well within the safe limits.
Elevated emotional reactivity in affective but not cognitive components of theory of mind: A psychophysiological study
Authors: Kalbe E. , Grabenhorst F. , Brand M. , Kessler J. , Hilker R. , Markowitsch H. J.
Published: June 2007

Recent research proposes that theory of mind (ToM), that is the ability to infer other people's mental state, is a multidimensional construct and that a distinction may be made between affective and cognitive ToM. We examined whether these two subcomponents of ToM correspond to different levels in skin conductance responses (SCRs). Seventeen healthy adults listened to ten affective (faux pas) ToM stories, ten cognitive ToM stories and ten non‐ToM stories. Results demonstrated significantly elevated SCR for affective ToM as compared with cognitive ToM and control stories, with no differences in SCR levels in the latter two story types. We discuss the possible underlying mechanisms for these differential psychophysiological correlates of affective and cognitive ToM processing, and suggest further investigations especially in clinical populations.
Fitness to drive following cerebral pathology: The Rookwood Driving Battery as a tool for predicting on‐road driving performance
Authors: McKenna Pat , Bell Vaughan
Published: June 2007

The use of neuropsychological testing to determine fitness to drive in people with neuropathology is likely to be an increasingly attractive alternative to on‐road testing for many candidates for assessment. The Rookwood Driving Battery has been shown to have good predictive value for determining some who are likely to fail an on‐road test in early studies. This study replicated earlier research by examining the predictive value and theoretical validity of the battery on a larger sample of 391 participants, as well as extending earlier analysis by examining the effect of older age (over 70 years) and the interaction between age and pathology on battery and on‐road performance. The battery demonstrated good positive and negative predictive values for predicting on‐road performance. There were significant effects of older age on both the Rookwood Battery performance and the on‐road test, with older adults performing significantly poorer on both. There was no interaction between age and pathology on the Rookwood Battery but on‐road age interacted with some pathologies to produce significantly poorer performances. Furthermore, correlation and regression analysis indicate that the battery is a powerful instrument that encompasses tests of core neuropsychological functions needed for driving.
Development of an assay for the intermembrane transfer of cholesterol by Niemann-Pick C2 protein
Authors: Babalola Jonathan O. , Wendeler Michaela , Breiden Bernadette , Arenz Christoph , Schwarzmann Guenter , Locatelli-Hoops Silvia , Sandhoff Konrad
Published: June 2007

Niemann-Pick type C disease is an inherited fatal disorder characterized by the accumulation of unesterified cholesterol and other lipids in the endosomal/lysosomal compartment. Two independent genes responsible for this neurodegenerative disorder have been identified, but the precise functions of the encoded Niemann-Pick C1 (NPC1) and C2 (NPC2) proteins are not yet known. We developed a cell-free assay for measuring intermembrane lipid transport and examined the ability of bovine NPC2 (bNPC2) for intermembrane cholesterol transfer. NPC2 specifically extracts cholesterol from phospholipid bilayers and catalyzes intermembrane transfer to acceptor vesicles in a dose- and time-dependent manner. This transfer activity is dependent on temperature, pH, ionic strength, lipid composition of the model membranes, and the ratio of donor to acceptor vesicles. In model membranes, the presence of the lysosomal anionic phospholipids bis(monooleoylglycero)phosphate and phosphatidyl inositol significantly stimulated cholesterol transfer by NPC2, whereas bis(monomyristoylglycero)phosphate, phosphatidyl serine, and phosphatidic acid had no effect. Moreover, ceramide stimulated cholesterol transfer slightly, whereas sphingomyelin reduced cholesterol transfer rates. With our assay system we identified for the first time the ability of other lysosomal proteins, most notably the GM2-activator protein, to mediate intermembrane cholesterol transfer. This assay system promises to be a valuable tool for further quantitative and mechanistic studies of protein-mediated lipid transfer.
Inhibition of inducible tumor necrosis factor-α expression by the fungal epipolythiodiketopiperazine gliovirin
Authors: Rether Jan , Serwe Annegret , Anke Timm , Erkel Gerhard
Published: June 2007

TNF-α is a major pro-inflammatory cytokine that regulates further cytokine induction, especially of IL-1 and IL-6, in many human diseases including cancer, inflammation and immune disorders. In a search for new inhibitors of inducibleTNF-αpromoter activity and expression, cultures of the imperfect fungusTrichoderma harzianumwere found to produce gliovirin, a previously isolated epipolythiodiketopiperazine. Gliovirin inhibited inducibleTNF-αpromoter activity and synthesis in LPS/IFN-γ-stimulated macrophages/monocytes and Jurkat T-cells, co-stimulated with 12-O-tetradecanoylphorbol-13-acetate (TPA)/ionomycin, in a dose-dependent manner, with IC50values ranging from 0.21 to 2.1 μM (0.1–1 μg/ml). Studies on the mode of action revealed that gliovirin suppresses TNF-α synthesis by inhibiting the activation of extracellular signal-regulated kinase (ERK), thereby blocking the pathway leading to activation of the transcription factors AP-1 and NF-κB, the latter of which is involved in the inducible expression of many pro-inflammatory genes. Gliovirin also significantly reduced TPA/ionomycin-inducedIL-2mRNA levels and synthesis in Jurkat cells at low micromolar concentrations.
Cantonese e-discourse: A new hybrid variety of English
Authors: Fung Loretta , Carter Ronald
Published: June 2007

While English remains the most dominant language used on the Internet, studies have primarily investigated computer-mediated interactions in English. Little linguistic research has, however, investigated how English and other languages interact online. Based on a 20,000-word corpus of private ICQ (‘I Seek You’) data, this paper analyses the online linguistic strategies and features of eighteen NNS university students from Hong Kong studying in Britain. The study witnesses the evolution of a new hybrid variety of English, an emergent bimodality with an informal speakerly style produced in a context of synchronicity. The findings demonstrate how the interlocutors adopt and adapt conventions of oral and written discourse to interact creatively in a context with spatio-temporal constraints in order to co-construct interpersonal convergence and to express their cultural identity. The speech modifications and linguistic play evidenced within code-switching, borrowing of Cantonese discourse markers, relexicalisation, and prosodic effects can be considered part of an e-discourse repertoire used to achieve interactional purposes and to articulate cultural identity.
So, und so, und so weiter. Vom Sinn und Unsinn der Wortklassifikation / So, und so, und so weiter. On the purpose and nonsense of part-of-speech classification
Authors: Hennig Mathilde
Published: June 2007

The article addresses the empirical problem of part-of-speech classification. In order to illustrate this problem, the study presents an analysis of 100 instances of the use of
Dmitri Zakharine: Von Angesicht zu Angesicht. Der Wandel direkter Kommunikation in derostund westeuropäischen Neuzeit. / From Face to Face. The change of direct communication in East and Western European modern times
Authors: Hermanns Fritz
Published: June 2007

So ein dickes Biest von Buch! 637 Seiten, ohne das Literaturverzeichnis und das Sachregister, die noch hinzukommen. Wer wird das von vorn bis hinten lesen? Wohl nur ExpertInnen für das nonverbale Kommunikationsverhalten – denn das ist das Thema dieses Buches – in Ost- und in Westeuropa ab dem 16. Jahrhundert bis ungefähr 1900, d.h. KulturwissenschaftlerInnen, die auf diese Kulturräume und auf diesen Zeitraum spezialisiert sind. Zwar kann ich versichern, aufgrund eigener Leseerfahrung, dass sich die vollständige Lektüre dieses Buches auch für andere Kommunikations- und KulturwissenschaftlerInnen lohnen würde, hege aber wenig Hoffnung, damit zusätzliche LeserInnen für das ganze Buch werben zu können. Alle KollegInnen, die ich kenne, haben für die eigene Horizonterweiterung und Weiterbildung außerhalb der eigenen Forschungsgebiete kaum noch Energie- und Zeitreserven und müssen schon froh sein, wenn sie es nur schaffen, jedenfalls in ihrem allerengsten Wissenschaftsbereich mit der Buch- und Artikelproduktion durch die Lektüre alles Einschlägigen mitzuhalten. Ich empfehle deshalb das Buch von Zakharine meiner germanistisch-linguistischen Fachmitgenossenschaft nur erstens zur Anschaffung (der Preis von rund 60 Euro ist gerade noch erträglich), zweitens zum Nachschlagen, drittens aber auch zum darin Stöbern oder Schmökern. Für die potenziellen LeserInnen, die darin nur entweder nachschlagen oder kursiv stöbernd lesen wollen werden, schreibe ich hier.
Language History from Below. Linguistic Variation in the Germanic Languages from 1700–2000, University of Bristol, 6–8 April 2005
Authors: Auer Anita , Freienstein Jan Claas
Published: June 2007

Im Anschluss an die zwei Jahre zuvor an der University of Bristol abgehaltene Konferenz zum Thema „Sprachpurismus“ (vgl. ZGL 31, 2003, 310-316) gingen auf Einladung von
AN INDEX OF MANAGEMENT INTENSITY FOR COFFEE AGROECOSYSTEMS TO EVALUATE BUTTERFLY SPECIES RICHNESS
Authors: Mas Alexandre H. , Dietsch Thomas V.
Published: June 2007

In spite of the attention that has been focused on the importance of traditional, shade coffee production for biodiversity, little is known about the relative conservation value of different systems of managing the shade canopy. We surveyed fruit‐feeding butterfly species richness and vegetation structure on different shade coffee management systems in Chiapas, Mexico, that ranged from intensive commercial to traditional, rustic systems. The impact of management on the diversity and structure of the shade canopy in each coffee production system was quantified and compared using a Management Index. This Management Index revealed statistically significant differences between management systems that previously were distinguished by researchers using qualitative, “gestalt” categories. Butterfly species richness was found to decline as management intensity increased, but a significant drop was found between the rustic system and the other more intensive systems, corroborating the importance of preserving rustic, shade coffee production for the conservation of biodiversity. Fruit‐feeding butterflies were found to be very sensitive to the intensification of management of the shade canopy, so they may be an effective way to monitor ecological changes that accompany intensification within the coffee agroecosystem. Additionally, the vegetation Management Index may prove useful for quantifying management practices to evaluate certification criteria for conservation benefits.
POTENTIAL FOR SELF‐DEFEATING BIOLOGICAL CONTROL? VARIATION IN HERBIVORE VULNERABILITY AMONG INVASIVE SPARTINA GENOTYPES
Authors: Garcia-Rossi Dino , Rank Nathan , Strong Donald R.
Published: June 2007

Invasive species can experience strong selection in their new environments. Some populations of invasive Spartina spp. cordgrass in Pacific estuaries have been separated from the specialist planthopper Prokelisia marginata for many generations while virtually no native populations, in estuaries of the Atlantic and Gulf coasts of North America, have experienced this separation. Contemplating the implications for biological control, we compared native cordgrass populations for resistance and tolerance to the planthopper with invasive ones that have been separated from the herbivore from many generations.

We found that plant genotypes varied more in their ability to resist and support planthoppers in a population that had been separated from the herbivore for many generations (in Willapa Bay, Washington, USA) than in one that had been consistently exposed to the herbivore (in San Francisco Bay, California, USA). In the former, some plant genotypes experienced >50% shoot mortality while others experienced none. In contrast, in the latter no genotype experienced >20% shoot mortality. Population growth rates of the herbivore paralleled this pattern among plant genotypes from the two populations. Extending previous observations, we found generally lower resistance and tolerance among six (nonnative) cordgrass populations that have been long‐separated from the planthopper than in six (native) cordgrass populations that had been consistently exposed to it.

One Willapa Bay genotype of S. alterniflora was quite tolerant of the planthopper while lacking resistance; the high densities of the insect that grew on this genotype did it virtually no harm. Plant genotypes with this combination of traits are insidious to biological control. Initially they could contribute to control by fostering herbivores that harm vulnerable genotypes. However, as these tolerant plant genotypes increase in frequency, the effectiveness of biological control would decrease. Prokelisia marginata has recently been released in Willapa Bay for biological control of S. alterniflora. Our findings of tolerant but nonresistant genetic cordgrass variants suggest the need for complementary chemical and/or mechanical control of less vulnerable genotypes. Attention to the frequency and nature of genetic variation in vulnerability to natural enemies in target species is germane to both the science and the practice of biological control.
ESTIMATION OF HABITAT‐SPECIFIC DEMOGRAPHY AND POPULATION GROWTH FOR PEREGRINE FALCONS IN CALIFORNIA
Authors: Kauffman Matthew J. , Frick Winifred F. , Linthicum Janet
Published: June 2007

American Peregrine Falcons in California (Falco peregrinus anatum) have been managed in one of the largest reintroduction programs in the history of endangered species management. However, as for most other widespread natural populations, the spatial and temporal dynamics of California Peregrines have remained poorly understood. Long‐term monitoring data on this highly managed species present a unique opportunity for retrospective analysis of the factors contributing to the successful recovery of Peregrine Falcons in California, as well as demographic differences between habitat types. We used a newly developed mark–recapture model (the Barker model), which allows the simultaneous use of recaptures, dead recoveries, and live resightings, to provide estimates of first‐year, second‐year, and adult survival of Peregrine Falcons in the mid‐ and south‐coast regions of California. Annual survival rates for second‐year and adult Peregrines were estimated at 86%. Through model fitting, we show positive effects of urban habitats on first‐year survival. In our best‐fit models, first‐year birds fledged in urban areas had a survival rate of 65%, whereas rural (non‐urban) first‐year survival was only 28%. The introduction method also influenced first‐year survival after dispersal; in rural areas, estimated survival of hacked young (after independence) was lower than estimated survival of wild‐reared young. We also show that birds in urban habitats have significantly higher fecundity rates than birds in rural habitats, even though the fecundity of rural breeders has increased significantly over the last two decades. We argue that the strong habitat differences in first‐year survival combined with lower fecundity rates in rural habitats (due to slower improvement in eggshell thinning rates) facilitates spatial structuring of the California Peregrine population. Matrix population models constructed for both rural and urban habitats support this assessment. The temporally averaged population growth rate in urban habitats was estimated as λ = 1.28, compared to λ = 0.99 in rural habitats. Yearly analytical λ values in rural habitat predict declining population growth (λ < 1) throughout the 1980s and increasing population growth (λ > 1) in the 1990s due to improved reproductive performance. These results indicate that the introduction effort was pivotal in recovering the rural population in this portion of its former habitat, because intrinsic growth rates alone would have been insufficient to yield the observed population recovery.
SEASONAL AND DEPTH VARIATION OF SOIL MOISTURE IN A BURNED OPEN SAVANNA (CAMPO SUJO) IN CENTRAL BRAZIL
Authors: Quesada C. A. , Miranda A. C. , Hodnett M. G. , Santos A. J. B. , Miranda H. S. , Breyer L. M.
Published: June 2007

The soil water regimes of two areas of open savanna (campo sujo) near Brasilia, Brazil, were monitored between August 1999 and November 2000. Each area was subjected to a different fire regime. Soil water content was measured to a depth of 3.6 m, using a neutron probe. The profile storage at the end of the 1999 and 2000 dry seasons was very similar despite a difference in dry season duration and large differences in rainfall in the preceding wet seasons, indicating that the vegetation is conservative in its water use. In the last two months of the dry season, the water content of the upper 0.6 m of the soil profile did not decrease further, suggesting that the vegetation had used all of the available water in this layer. The seasonal variation in soil water storage to a depth of 3.6 m was 403 mm, 65% of which occurred below 1 m. The wet and dry season evaporation rates were estimated to be 2.4 mm/d and 1.6 mm/d, respectively, but for a month after fire, before regrowth started, the evaporation rate was less than 0.5 mm/d.
CANOPY DAMAGE AND RECOVERY AFTER SELECTIVE LOGGING IN AMAZONIA: FIELD AND SATELLITE STUDIES
Authors: Asner Gregory P. , Keller Michael , Pereira, Jr Rodrigo , Zweede Johan C. , Silva Jose N. M.
Published: June 2007

We combined a detailed field study of canopy gap fraction with spectral mixture analyses of Landsat 7 ETM+ satellite imagery to assess landscape and regional dynamics of canopy damage following selective logging in an eastern Amazon forest. Our field studies encompassed measurements of ground damage and canopy gap fractions along multitemporal sequences of post‐harvest regrowth of 0.5–3.5 yr. Areas used to stage harvested logs prior to transport, called log decks, had the largest forest gap fractions, but their contribution to the landscape‐level gap dynamics was minor. Tree falls were spatially the most extensive form of canopy damage following selective logging, but the canopy gap fractions resulting from them were small. Reduced‐impact logging resulted in consistently less damage to the forest canopy than did conventional logging practices. This was true at the level of individual landscape strata such as roads, skids, and tree falls as well as at the area‐integrated scale.

A spectral mixture model was employed that utilizes bundles of field and image spectral reflectance measurements with Monte Carlo analysis to estimate high spatial resolution (subpixel) cover of forest canopies, exposed nonphotosynthetic vegetation, and soils in the Landsat imagery. The method proved highly useful for quantifying forest canopy cover fraction in log decks, roads, skids, tree fall, and intact forest areas, and it tracked canopy damage up to 3.5 yr post‐harvest. Forest canopy cover fractions derived from the satellite observations were highly and inversely correlated with field‐based canopy gap fraction. Subsequent regional‐scale estimates of forest gap fraction were derived from the combination of field‐ and satellite‐based measurements. A 450‐km2 study of gap fraction showed that approximately one‐half of the canopy opening caused by logging is closed within one year of regrowth following timber harvests. This is the first regional‐scale study utilizing field measurements, satellite observations, and models to quantify forest canopy damage and recovery following selective logging in the Amazon.
EXCHANGE OF SHORT‐CHAIN ALDEHYDES BETWEEN AMAZONIAN VEGETATION AND THE ATMOSPHERE
Authors: Rottenberger S. , Kuhn U. , Wolf A. , Schebeske G. , Oliva S. T. , Tavares T. M. , Kesselmeier J.
Published: June 2007

As a part of the LBA‐EUSTACH (EUropean Studies on Trace Gases and Atmospheric CHemistry as a contribution of the Large‐scale Biosphere–Atmosphere experiment in Amazonia) project, the exchanges of formaldehyde (HCHO) and acetaldehyde (CH3CHO) between Amazonian vegetation and the atmosphere were investigated by branch enclosures and compared with gradient measurements during the wet‐to‐dry transition and dry‐to‐wet‐transition periods at a remote forest site in Brazil, 1999. Branch enclosure measurements of several tree species showed emission as well as deposition of short‐chain aldehydes, but fluxes were clearly dominated by deposition during both seasons. This bidirectional exchange was found to depend mainly on the actual ambient concentrations of these compounds and to exhibit a compensation point below 0.6 ppb of the compound in air with deposition velocities between 0.16 and 0.21 cm/s during the wet‐to‐dry season. During the dry‐to‐wet season, the deposition velocities and the compensation point increased. Under the clean air conditions of the wet‐to‐dry season, the major pathway for the aldehyde uptake was via leaf stomata. For HCHO, a mesophyll resistance of the same order of magnitude as the stomatal resistance contributed to the total leaf surface resistance, whereas the mesophyll resistance for CH3CHO was small, allowing a rapid uptake. This finding indicates a major contribution of metabolic consumption processes in addition to physical and chemical processes to the overall resistance. During the dry‐to‐wet period, when ambient air concentrations substantially increased, we found indications for an additional deposition to the leaf cuticle. Vertical gradient measurements of ambient air concentrations in and above the canopy closely agreed with the branch enclosure studies and confirmed that the forest acts rather as a sink than as a direct source for HCHO and CH3CHO. Diel courses of ambient air concentrations and ratios of HCHO and CH3CHO above the canopy suggest photochemical oxidation of biogenically or pyrogenically emitted precursor compounds as the major sources for short‐chain aldehydes in the tropical atmosphere.
MODELING FOREST UNDERSTORY FIRES IN AN EASTERN AMAZONIAN LANDSCAPE
Authors: Alencar Ane A. C. , Solórzano Luis A. , Nepstad Daniel C.
Published: June 2007

Forest understory fires are an increasingly important cause of forest impoverishment in Amazonia, but little is known of the landscape characteristics and climatic phenomena that determine their occurrence. We developed empirical functions relating the occurrence of understory forest fires to landscape features near Paragominas, a 35‐yr‐old ranching and logging center in eastern Amazonia. An historical sequence of maps of forest understory fire was created based on field interviews with local farmers and Landsat TM images. Several landscape features that might explain spatial variation in the occurrence of understory fires were also mapped and co‐registered for each of the sample dates, including: forest fragment size and shape, forest impoverishment through logging and understory fire, sources of ignition (settlements and charcoal pits), roads, forest edges, and others. The spatial relationship between forest understory fire and each landscape characteristic was tested by regression analyses. Fire probability models were then developed for various combinations of landscape characteristics. The analyses were conducted separately for years of the El Niño Southern Oscillation (ENSO), which are associated with severe drought in eastern Amazonia, and non‐ENSO years.

Most (91%) of the forest area that burned during the 10‐yr sequence caught fire during ENSO years, when severe drought may have increased both forest flammability and the escape of agricultural management fires. Forest understory fires were associated with forest edges, as reported in previous studies from Amazonia. But the strongest predictor of forest fire was the percentage of the forest fragment that had been previously logged or burned. Forest fragment size, distance to charcoal pits, distance to agricultural settlements, proximity to forest edge, and distance to roads were also correlated with forest understory fire. Logistic regression models using information on fragment degradation and distance to ignition sources accurately predicted the location of >80% of the forest fires observed during the ENSO event of 1997–1998. In this Amazon landscape, forest understory fire is a complex function of several variables that influence both the flammability and ignition exposure of the forest.