bluuebunny/crossref_metadata_2025_split huggingface dataset:
Invasion of the Arabidopsis Genome by the Tobacco Retrotransposon Tnt1 Is Controlled by Reversible Transcriptional Gene Silencing
Authors: Pérez-Hormaeche Javier , Potet Frédérique , Beauclair Linda , Le Masson Ivan , Courtial Béatrice , Bouché Nicolas , Lucas Hélène 
Published: May 2008

AbstractLong terminal repeat (LTR) retrotransposons are generally silent in plant genomes. However, they often constitute a large proportion of repeated sequences in plants. This suggests that their silencing is set up after a certain copy number is reached and/or that it can be released in some circumstances. We introduced the tobacco (Nicotiana tabacum) LTR retrotransposon Tnt1 into Arabidopsis (Arabidopsis thaliana), thus mimicking the horizontal transfer of a retrotransposon into a new host species and allowing us to study the regulatory mechanisms controlling its amplification. Tnt1 is transcriptionally silenced in Arabidopsis in a copy number-dependent manner. This silencing is associated with 24-nucleotide short-interfering RNAs targeting the promoter localized in the LTR region and with the non-CG site methylation of these sequences. Consequently, the silencing of Tnt1 is not released in methyltransferase1 mutants, in contrast to decrease in DNA methylation1 or polymerase IVa mutants. Stable reversion of Tnt1 silencing is obtained when the number of Tnt1 elements is reduced to two by genetic segregation. Our results support a model in which Tnt1 silencing in Arabidopsis occurs via an RNA-directed DNA methylation process. We further show that silencing can be partially overcome by some stresses.
Inactive Methyl Indole-3-Acetic Acid Ester Can Be Hydrolyzed and Activated by Several Esterases Belonging to the AtMES Esterase Family of Arabidopsis
Authors: Yang Yue , Xu Richard , Ma Choong-je , Vlot A. Corina , Klessig Daniel F. , Pichersky Eran 
Published: May 2008

Abstract
The plant hormone auxin (indole-3-acetic acid [IAA]) is found both free and conjugated to a variety of carbohydrates, amino acids, and peptides. We have recently shown that IAA could be converted to its methyl ester (MeIAA) by the Arabidopsis (Arabidopsis thaliana) enzyme IAA carboxyl methyltransferase 1. However, the presence and function of MeIAA in vivo remains unclear. Recently, it has been shown that the tobacco (Nicotiana tabacum) protein SABP2 (salicylic acid binding protein 2) hydrolyzes methyl salicylate to salicylic acid. There are 20 homologs of SABP2 in the genome of Arabidopsis, which we have named AtMES (for methyl esterases). We tested 15 of the proteins encoded by these genes in biochemical assays with various substrates and identified several candidate MeIAA esterases that could hydrolyze MeIAA. MeIAA, like IAA, exerts inhibitory activity on the growth of wild-type roots when applied exogenously. However, the roots of Arabidopsis plants carrying T-DNA insertions in the putative MeIAA esterase gene AtMES17 (At3g10870) displayed significantly decreased sensitivity to MeIAA compared with wild-type roots while remaining as sensitive to free IAA as wild-type roots. Incubating seedlings in the presence of [14C]MeIAA for 30 min revealed that mes17 mutants hydrolyzed only 40% of the [14C]MeIAA taken up by plants, whereas wild-type plants hydrolyzed 100% of absorbed [14C]MeIAA. Roots of Arabidopsis plants overexpressing AtMES17 showed increased sensitivity to MeIAA but not to IAA. Additionally, mes17 plants have longer hypocotyls and display increased expression of the auxin-responsive DR5:β-glucuronidase reporter gene, suggesting a perturbation in IAA homeostasis and/or transport. mes17-1/axr1-3 double mutant plants have the same phenotype as axr1-3, suggesting MES17 acts upstream of AXR1. The protein encoded by AtMES17 had a K m value of 13 μ m and a K cat value of 0.18 s−1 for MeIAA. AtMES17 was expressed at the highest levels in shoot apex, stem, and root of Arabidopsis. Our results demonstrate that MeIAA is an inactive form of IAA, and the manifestations of MeIAA in vivo activity are due to the action of free IAA that is generated from MeIAA upon hydrolysis by one or more plant esterases.
Auxin Responses in Mutants of the Arabidopsis CONSTITUTIVE PHOTOMORPHOGENIC9 Signalosome
Authors: Dohmann Esther Mirjam Natascha , Levesque Mitchell Paul , Isono Erika , Schmid Markus , Schwechheimer Claus 
Published: May 2008

AbstractThe CONSTITUTIVE PHOTOMORPHOGENIC9 (COP9) signalosome (CSN) is an evolutionarily conserved multiprotein complex that interacts with cullin-RING type E3 ubiquitin ligases (CRLs). CSN subunit 5 (CSN5), which, when incorporated into CSN, can deconjugate the NEDD8 modification from the cullin subunit of CRLs, is essential for CSN's role in controlling CRL activity. Whether the CSN5 monomer, which is maintained in csn mutants such as csn3 or csn4, has a functional role, remains to be established. We performed a comparative gene expression-profiling experiment with Arabidopsis (Arabidopsis thaliana) csn3, csn4, and csn5 mutants, and we show here that these mutants cannot be distinguished at the transcriptional level. Furthermore, we show that csn3 csn5 mutants are morphologically indistinguishable from csn3 or csn5 mutants. Taken together, these data suggest that the CSN5 monomer does not have a function that leads to transcriptional or morphological changes in the csn mutants. We further examined auxin responses in csn mutants. Whereas CSN had previously been shown to be required for the auxin response-regulatory E3 complexes, specifically SCFTIR1, the csn mutant phenotype suggests that CSN is not essential for auxin responses. We present physiological and genetic data that indicate that auxin responses are indeed only partially impaired in csn mutants and that this is not the result of maternally contributed CSN. Finally, we discuss these findings in the context of the current understanding of the role of neddylation and CSN-mediated deneddylation for CRL activity.
An improved SUMO fusion protein system for effective production of native proteins
Authors: Lee Chien‐Der , Sun Hui‐Chien , Hu Su‐Ming , Chiu Ching‐Feng , Homhuan Atthachai , Liang Shu‐Mei , Leng Chih‐Hsiang , Wang Ting‐Fang 
Published: May 2008

AbstractExpression of recombinant proteins as fusions with SUMO (small ubiquitin‐related modifier) protein has significantly increased the yield of difficult‐to‐express proteins in Escherichia coli. The benefit of this technique is further enhanced by the availability of naturally occurring SUMO proteases, which remove SUMO from the fusion protein. Here we have improved the exiting SUMO fusion protein approach for effective production of native proteins. First, a sticky‐end PCR strategy was applied to design a new SUMO fusion protein vector that allows directional cloning of any target gene using two universal cloning sites (Sfo1 at the 5′‐end and XhoI at the 3′‐end). No restriction digestion is required for the target gene PCR product, even the insert target gene contains a SfoI or XhoI restriction site. This vector produces a fusion protein (denoted as His6‐Smt3‐X) in which the protein of interest (X) is fused to a hexahistidine (His6)‐tagged Smt3. Smt3 is the yeast SUMO protein. His6‐Smt3‐X was purified by Ni2+ resin. Removal of His6‐Smt3 was performed on the Ni2+ resin by an engineered SUMO protease, His6‐Ulp1403–621‐His6. Because of its dual His6 tags, His6‐Ulp1403–621‐His6 exhibits a high affinity for Ni2 resin and associates with Ni2+ resin after cleavage reaction. One can carry out both fusion protein purification and SUMO protease cleavage using one Ni2+‐resin column. The eluant contains only the native target protein. Such a one‐column protocol is useful in developing a better high‐throughput platform. Finally, this new system was shown to be effective for cloning, expression, and rapid purification of several difficult‐to‐produce authentic proteins.
Neutrophilic, urticaria‐like erythema associated with immunoglobulin A monoclonal gammopathy of undetermined significance
Authors: DEMITSU Toshio , KAKURAI Maki , AZUMA Ryuichi , HIRATSUKA Yuichiro , UMEMOTO Naoka , YONEDA Kozo 
Published: May 2008

ABSTRACTA 70‐year‐old‐male had suffered from non‐pruritic, erythematous eruptions on the trunk for 3 months without any general symptoms. The individual lesions lasted for several days. Laboratory investigation showed marked elevation of serum immunoglobulin A (2235 mg/dL) with monoclonal gammopathy (IgA k‐type). Monoclonal gammopathy of undetermined significance was diagnosed. Histopathological examination of the eruption revealed diffuse neutrophilic infiltration with leukocytoclasia in the dermis. There was no vasculitis. Treatment with antihistamines alone was not effective. Diaphenyl sulfone (DDS) at 75 mg/day dramatically improved the skin lesions. A similar case of urticarial erythema associated with IgA myeloma has been previously reported. We suggest that neutrophilic, urticaria‐like erythema associated with IgA monoclonal gammopathy may be regarded as a new entity.
Erythema elevatum diutinum with rare distribution as a first clinical sign of non‐Hodgkin's lymphoma: A novel association?
Authors: HATZITOLIOS Apostolos , TZELLOS Thrasivoulos George , SAVOPOULOS Christos , TZALOKOSTAS Vasileios , KAIAFA Georgia , PSOMAS Evaggelos , APOSTOLOPOULOU Martha , PAPADOPOULOS Athanasios 
Published: May 2008

ABSTRACTWe present a case of a 78‐year‐old man with erythema elevatum diutinum as a first clinical sign of non‐Hodgkin's lymphoma. The patient developed erythema elevatum diutinum with an unusual distribution involving the trunk. Erythema elevatum diutinum is a rare dermatosis that is considered to be a localized, low‐grade form of leukocytoclastic vasculitis associated with neoplastic, autoimmune and infectious processes. It is probably mediated by immune complexes. Recent studies report hematological disease as the most common factor associated with erythema elevatum diutinum. Many hematological diseases, such as myeloma, myelodysplastic syndrome and immunoglobulin (Ig)A monoclonal gammopathy, have been reported in association with erythema elevatum diutinum, but none with IgM monoclonal gammopathy and only one with malignant lymphoma. We would like to add IgM monoclonal gammopathy and non‐Hodgkin's lymphoma as one of the diseases associated with erythema elevatum diutinum considering that the activity of erythema elevatum diutinum and non‐Hodgkin's lymphoma fluctuated in parallel in the present case.
Anaesthesia for Angelman syndrome
Authors: Ramanathan K. R. , Muthuswamy D. , Jenkins B. J. 
Published: May 2008

SummaryWe describe the administration of anaesthesia to a patient with Angelman syndrome, which is characterised by an abnormality of chromosome 15, where a subunit of the GABA receptor is coded. This has far‐reaching anaesthetic implications as many drugs used in anaesthesia are thought to act via GABA receptors. Our patient had an uneventful peri‐operative period and was discharged home on the second postoperative day.
Anaesthesia and high altitude: a history
Authors: Firth P. G. , Pattinson K. T. S. 
Published: May 2008

SummaryDuring an expedition to climb Everest in 1933, expedition doctor Raymond Greene administered an open‐drop chloroform anaesthetic to a Tibetan patient at an altitude of more than 14 000 feet. The patient’s subsequent apparent cardiopulmonary arrest has long been attributed to the effects of altitude on anaesthetic delivery. However, anaesthetics can be safely administered at a wide variety of altitudes by adequately trained and experienced anaesthetists. The problems may have arisen from an inadequate depth of anaesthesia consequent to decreased chloroform vaporisation in a cold environment, Greene’s concern about potential depression of ventilation and the contemporary lack of a precise approach to assessing depth of anaesthesia.
Regional anaesthesia for limb surgery: a review of anaesthetists’ beliefs and practice in the Oxford region*
Authors: Feely N. M. , Popat M. T. , Rutter S. V. 
Published: May 2008

SummaryWe conducted a postal survey of 210 anaesthetists in the Oxford region to determine their views and practice regarding the timing of regional anaesthesia when combined with general anaesthesia for adults undergoing limb surgery and to compare the results with those obtained in a similar survey conducted in 2001. Of the 151 respondents (72% response rate), 102 (68%) regularly combined regional and general anaesthesia for adult limb surgery. Over 80% believed that central neuraxial blocks should be performed before general anaesthesia. This matched their current practice, marking a change from 2001. Significantly fewer anaesthetists believed it necessary to perform peripheral nerve blocks before general anaesthesia than in 2001, marking another significant change in practice. Overall, the results indicate an increased popularity of regional blocks in combination with general anaesthesia when compared with 2001 practice, which we believe is related to high quality advanced training modules now on offer to senior trainees in the Oxford region.
The incidence of bacteraemia associated with tracheal intubation
Authors: Valdés C. , Tomás I. , Álvarez M. , Limeres J. , Medina J. , Diz P. 
Published: May 2008

SummaryExpert committees on bacterial endocarditis prophylaxis have provided differing opinions on whether tracheal intubation is an ‘at‐risk’ manipulation. We studied the incidence of bacteraemia after orotracheal and nasotracheal intubation. The study group comprised 110 patients who underwent surgery under general anaesthesia. Venous blood samples were collected from each patient at baseline and 30 s after intubation. Samples were processed with conventional microbiological techniques. Bacteraemia after tracheal intubation was detected in 13 patients (11.8%); six after orotracheal intubation and seven after nasotracheal intubation. Staphylococci and streptococci were the most commonly isolated bacterial species. Seven isolates (54%) were resistant to oxacillin. The incidence of bacteraemia was similar after orotracheal (12.0%) and nasotracheal intubation (11.7%). The recommendation for bacterial endocarditis prophylaxis with flucloxacillin when performing nasotracheal intubation, as put forward by the British Society for Antimicrobial Chemotherapy, needs further consideration.
Intravascular iodinated contrast media and the anaesthetist
Authors: Dickinson M. C. , Kam P. C. A. 
Published: May 2008

SummaryThe use of intravascular iodinated contrast media (ICM) in radiological investigations is common. Increasingly, anaesthetists and intensivists are involved in the care of patients undergoing these investigations. Whilst the use of ICM is generally safe there are important adverse effects that need to be recognised and measures instigated to prevent or treat these effects. In patients at risk of developing adverse reactions it is important to consider alternative modes of imaging so that ICM can be avoided. Strategies for the prevention of ICM nephropathy should be considered in all patients receiving ICM. Currently intravascular volume expansion with 0.9% saline has the strongest evidence base. The use of isotonic sodium bicarbonate combined with N‐acetylcysteine appears promising in providing further benefits. Although the use of N‐acetylcysteine alone has not been shown to significantly reduce the incidence of ICM nephropathy it is cheap, has few adverse effects and it would seem reasonable to continue its use in conjunction with intravascular volume expansion. The routine use of corticosteroid and antihistamine premedication is not always effective in preventing general adverse reactions.
A comparison of cervical spine movement during laryngoscopy using the Airtraq® or Macintosh laryngoscopes*
Authors: Hirabayashi Y. , Fujita A. , Seo N. , Sugimoto H. 
Published: May 2008

SummaryThe Airtraq® laryngoscope has an oropharyngeal airway‐shaped blade that provides a non‐line‐of‐sight view of the glottis. The configuration of the blade should mean that less movement of the cervical spine is required during laryngeal visualisation.We compared the degree of cervical spine movement in laryngoscopy performed using the Airtraq and conventional Macintosh laryngoscope. In 20 patients requiring general anaesthesia and tracheal intubation, we measured cervical spine movement using radiography in the same patient during consecutive procedures using the two laryngoscopes. Although significant movement of the cervical spine from baseline was noted during all procedures (p < 0.05), cervical spinal extension with the Airtraq was 29% less than that measured during Macintosh laryngoscopy between the occiput and C4, and 44% less at the C3/C4 motion segment (p < 0.05). Anterior deviations of the vertebral bodies from baseline were 32%, 35%, 38% and 40% less at the atlas, C2, C3, and C4 vertebrae, respectively, during Airtraq laryngoscopy than those measured during Macintosh laryngoscopy (p < 0.01). Our study demonstrated that laryngoscopy using the Airtraq laryngoscope involves less movement of the cervical spine compared to conventional procedures using a Macintosh laryngoscope.
Interleukin (IL)‐17 promotes macrophages to produce IL‐8, IL‐6 and tumour necrosis factor‐α in aplastic anaemia
Authors: Gu Yan , Hu Xiaojing , Liu Chuanfang , Qv Xun , Xu Conggao 
Published: May 2008

SummaryAplastic anaemia (AA) is thought to be an autoimmune‐mediated disease with active destruction of haematopoietic cells through a T helper type 1 (Th1) cell response. Interleukin (IL)‐17 is a potent proinflammatory cytokine produced by activated memory T cells. Recent studies indicate that IL‐17 might be an essential effector cytokine in the T‐cell mediated autoimmune process. It can drive the production of tumour necrosis factor‐α (TNF‐α), IL‐1 β, IL‐6 and IL‐8 by a variety of cells. The present study investigated the genetic and protein expression of IL‐17 in patients with AA. The effect of IL‐17 on IL‐6 and IL‐8 production by macrophages was also studied. AA patients showed an elevated expression of IL17A mRNA in bone marrow mononuclear cells and peripheral blood mononuclear cells. Higher IL‐17 in bone marrow and peripheral blood plasma was also observed in AA patients compared with normal controls. IL‐17 induced the production of IL‐6 and IL‐8 by macrophages both from patients with AA and normal controls. IL‐17 stimulation also resulted in the production of TNF‐α. These results suggested that elevated expression of IL‐17 and IL‐17‐induced IL‐6, IL‐8 and TNF‐α may be involved in the mechanisms of AA.
Pan‐neurotrophin receptor p75NTR expression is strongly induced in lesional atopic mast cells
Authors: Fischer T. C. , Lauenstein H.‐D. , Serowka F. , Pilzner C. , Groneberg D. A. , Welker P. 
Published: May 2008

SummaryBackground
Neurotrophins such as nerve growth factor or brain‐derived neurotrophic factor influence neuronal proliferation and differentiation via the low‐affinity pan‐neurotrophin receptor p75NTR that may play a pivotal role in linking the immune with the nervous system. Because the precise regulation of p75NTR gene transcription in mast cells under states of allergic inflammation has not been investigated in detail so far, the present studies assessed the gene regulation and expression of this receptor.Methods
Transcriptional expression of p75NTR in human skin was studied in isolated cutaneous cells by means of RT‐PCR. In situ lesional mast cell p75NTR expression was analysed by immunohistochemistry.Results
The p75NTR mRNA expression was found in isolated human skin mast cells and keratinocytes. Lower mRNA levels were present in fibroblasts and melanocytes but no transcripts were found in endothelial cells. The p75NTR protein expression was found in situ in lesional and non‐lesional mast cells. A significantly increased expression of p75NTR protein was found in atopic dermatitis lesional mast cells when compared with control mast cell expression (P<0.05).Conclusion
The demonstration of an increased level of p75NTR gene transcription in lesional mast cells points to an induction of low‐affinity neurotrophin receptor sensitivity of mast cells under states of allergic inflammation. Topically administered neurotrophin receptor‐modulating compounds may act as anti‐inflammatory mediators in cutaneous allergic inflammation.
Nitric oxide evaluation in upper and lower respiratory tracts in nasal polyposis
Authors: Delclaux C. , Malinvaud D. , Chevalier‐Bidaud B. , Callens E. , Mahut B. , Bonfils P. 
Published: May 2008

SummaryBackground
A decrease in nasal nitric oxide (NO) and an increase in exhaled NO have been demonstrated in patients with nasal polyposis (NP).Objectives
The aims were to evaluate the flux of NO from the three compartments of the respiratory tract, namely, upper nasal, lower conducting and distal airways, and to search for relationships between NO parameters and indexes of upper and lower disease activity (bronchial reactivity and obstruction). The effect of medical treatment of polyposis was also evaluated.Methods
Seventy patients with polyposis were recruited. At baseline, pulmonary function tests (spirometry, plethysmography, bronchomotor response to deep inspiration using forced oscillation measurement of resistance of respiratory system, methacholine challenge, multiple flow rates of exhaled NO and nasal NO measurements) were performed together with an assessment of polyposis [clinical, endoscopic and computed tomography (CT) scores].Results
Statistical relationships were demonstrated between nasal NO flux and severity scores (clinical: ρ=−0.31, P=0.015; endoscopic: ρ=−0.57, P<0.0001; CT: ρ=−0.46, P=0.0005), and between alveolar NO concentration and distal airflow limitation (FEF25–75, ρ=−0.32, P=0.011). Thirty‐six patients were assessed after 11 [7–13] (median [interquartile]) months of medical treatment, demonstrating an improvement in clinical and endoscopic scores, an increase in nasal NO flux, a decrease in NO flux from conducting airways, an improvement in the mild airflow limitation (forced expiratory volume in 1 s, FEF25–75, even in non‐asthmatic patients) and a decrease in the bronchoconstrictor effect of deep inspiration.Conclusions
The medical treatment of NP improves both airway reactivity and obstruction, whatever the presence of asthma, suggesting a functional link between upper and lower airway functions.
When does a protein become an allergen? Searching for a dynamic definition based on most advanced technology tools
Authors: Mari A. 
Published: May 2008

SummarySince the early beginning of allergology as a science considerable efforts have been made by clinicians and researchers to identify and characterize allergic triggers as raw allergenic materials, allergenic sources and tissues, and more recently basic allergenic structures defined as molecules. The last 15–20 years have witnessed many centres focusing on the identification and characterization of allergenic molecules leading to an expanding wealth of knowledge. The need to organize this information leads to the most important question ‘when does a protein become an allergen?’ In this article, I try to address this question by reviewing a few basic concepts of the immunology of IgE‐mediated diseases, reporting on the current diagnostic and epidemiological tools used for allergic disease studies and discussing the usefulness of novel biotechnology tools (i.e. proteomics and molecular biology approaches), information technology tools (i.e. Internet‐based resources) and microtechnology tools (i.e. proteomic microarray for IgE testing on molecular allergens). A step‐wise staging of the identification and characterization process, including bench, clinical and epidemiological aspects, is proposed, in order to classify allergenic molecules dynamically. This proposal reflects the application and use of all the new tools available from current technologies.